Ming Chen

This review summarises the recent advances of covalent organic framework photocatalysts including structures and applications.

The objective of this investigation was to obtain a broad profile of veterinary antibiotics residues in animal wastewater and surface water around large-scale livestock and poultry farms in Jiangsu Province of China. Therefore, 53 samples collected from 27 large-scale animal farms in 11 cities and counties of Jiangsu Province in 2009, were monitored for 10 selected veterinary antibiotics using solid phase extraction and high performance liquid chromatography/electrospray ionization-tandem mass spectrometry (HPLC/ESI-MS/MS) techniques. Ten veterinary antibiotics were found in animal wastewaters, eight antibiotics were detected in pond waters, and animal farm-effluents and river water samples were contaminated by nine antibiotics. The most frequently detected antibiotics were sulfamethazine (75%), oxytetracycline (64%), tetracycline (60%), sulfadiazine (55%) and sulfamethoxazole (51%) which were detected with a maximum concentration of 211, 72.9, 10.3, 17.0 and 63.6 μg L(-1), respectively. The maximum concentration of 0.55 μg L(-1) for cyromazine, 3.67 μg L(-1) for chlortetracycline, 0.63 μg L(-1) for sulfadoxine, 39.5 μg L(-1) for doxycycline and 0.64 μg L(-1) for sulfaquinoxaline were determined in the collected samples. In general, the maximum concentration of the selected veterinary antibiotics was detected in animal wastewaters except for chlortetracycline in animal farm-effluents. In addition, residue levels of selected veterinary antibiotics in animal wastewater and surface water around the farms were related to animal species and have a high spatial variation.

The rapid development of plastic industrials has created a variety of plastic products, causing revolutionary progress in chemistry, physics, biology, and medicine. Large-scale production and applications of plastics increase their possibility of entering the environment. Previous environmental impact studies typically focused on the toxicity, behavior and fate; limited attention was paid on greenhouse gas emissions and climate change. With the increase of plastic waste, the threat of plastic pollution to the earth’s climate has been gradually taken seriously. Evidence showed that greenhouse gas emissions occur at every stage of the plastic life cycle, including extraction and transportation of plastic raw materials, plastic manufacturing, waste treatment and entering the environment. The oil and gas industries used to make plastics are the main sources of greenhouse gas emissions (from the extraction of raw materials to the manufacture of plastics). Emissions of greenhouse gases during manufacture are mainly controlled by the production facilities themselves, usually depending on the efficiency, configuration and service life of equipment. Additionally, there are some unintended impacts, including transport requirements, pipeline leakage, land use, as well as impeding forests as natural carbons sinks. Recycling of plastic waste energy seems to be a good way to deal with waste plastics, but this process will release a lot of greenhouse gases. With this energy conversion occurring, the incineration of plastic packing waste will become one of the main sources of greenhouse gas emissions. Furthermore, plastics released into the environment also slowly release greenhouse gases, and the presence of (micro)plastics in the ocean will seriously interfere with the carbon fixation capacity of the ocean. In its current form, greenhouse gas emissions from cradle to grave of plastics will reach 1.34 gigatons per year by 2030 and 2.8 gigatons per year by 2050. This will seriously consume the global remaining carbon budgets, thereby threatening the ability of the global community to keep global temperatures rising by below 1.5 °C even 2 °C by 2100. In order to achieve this goal, the total global greenhouse gas emissions must be kept within the remaining carbon budget of 420–570 gigatons. The accumulative greenhouse gas emissions from cradle to grave of plastics may exceed 56 gigatons by 2050 (approximately accounting for 10%–13% of the total remaining carbon budget). As the plastic industry plans to expand production on a large scale, the problem will worsen further. The World Economic Forum forecasted that by 2030, the production and use of plastics will grow at an annual rate of 3.8%, and this growth rate will fall to 3.5% per year from 2030 to 2050. However, there are significant challenges and uncertainties in this estimation, and challenge and uncertainty factors come from all aspects. Recently, several organizations and researchers have started to discern the relationship between greenhouse gas emissions and plastic industrials, but relevant research on these impacts is still in its infancy. Consequently, the contribution of plastic pollution to greenhouse gas emissions and climate change should be given immediate attention and it needs to further explore the impact of plastic pollution on greenhouse gas emission and climate change. The implementation of measures to solve or alleviate the (micro)plastic crisis was critical necessary and proposed: (1) production control of global plastics; (2) improving the treatment and disposal of plastic waste; and (3) assessment of the impact of global environmental (micro)plastics on climate.

The capacity to fix nitrogen is widely distributed in phyla of Bacteria and Archaea but has long been considered to be absent from the Pseudomonas genus. We report here the complete genome sequencing of nitrogen-fixing root-associated Pseudomonas stutzeri A1501. The genome consists of a single circular chromosome with 4,567,418 bp. Comparative genomics revealed that, among 4,146 protein-encoding genes, 1,977 have orthologs in each of the five other Pseudomonas representative species sequenced to date. The genome contains genes involved in broad utilization of carbon sources, nitrogen fixation, denitrification, degradation of aromatic compounds, biosynthesis of polyhydroxybutyrate, multiple pathways of protection against environmental stress, and other functions that presumably give A1501 an advantage in root colonization. Genetic information on synthesis, maturation, and functioning of nitrogenase is clustered in a 49-kb island, suggesting that this property was acquired by lateral gene transfer. New genes required for the nitrogen fixation process have been identified within the nif island. The genome sequence offers the genetic basis for further study of the evolution of the nitrogen fixation property and identification of rhizosphere competence traits required in the interaction with host plants; moreover, it opens up new perspectives for wider application of root-associated diazotrophs in sustainable agriculture.

Compost and biochar, used for the remediation of soil, are seen as attractive waste management options for the increasing volume of organic wastes being produced. This paper reviews the interaction of biochar and composting and its implication for soil amendment and pollution remediation. The interaction of biochar and composting affect each other's properties. Biochar could change the physico-chemical properties, microorganisms, degradation, humification and gas emission of composting, such as the increase of nutrients, cation exchange capacity (CEC), organic matter and microbial activities. The composting could also change the physico-chemical properties and facial functional groups of biochar, such as the improvement of nutrients, CEC, functional groups and organic matter. These changes would potentially improve the efficiency of the biochar and composting for soil amendment and pollution remediation. Based on the above review, this paper also discusses the future research required in this field.

Dye wastewater is an universal problem that restricts sustainable development. Adsorption is an effective technique for water purification due to high efficiency, economic feasibility and operational ease. Metal-organic frameworks (MOFs) as adsorbent has attracted great attention due to exceptionally high porosity, compositional and structural diversity, and highly tunable pore shape/size and surface functionality. This review focused on recent progress in different typological and structural MOFs as superior adsorbents for the efficient removal of toxic dyes. Optimized, modified, defective, compositive and derived MOFs could improve the adsorption performance of MOFs. In particular, some MOFs-based adsorbents with special structure were concerned. The interactions between dyes and MOFs-based materials are systematically summarized, including adsorption performance, kinetics, thermodynamics and mechanism. Finally, we propose our personal insights to the development of MOFs-based adsorbent better used for environmental pollution management.

The occurrence of microplastics in drinking water systems has increasingly become a major environmental challenge. Although the potential impacts of microplastics in drinking water on humans are not yet fully understood, microplastics attract the public health concern when they are consumed by humans through drinking water systems. Current drinking water treatment plants constitute an obstacle to the entry of microplastics from raw water into daily drinking water. Therefore, understanding the behaviors of drinking water treatment process and the fates of microplastics in drinking water treatment plants are very important. We systematically reviewed the available knowledge on the global existence of microplastics in raw water, treated water and tap water in this paper. This will offer a new perspective for the threat of microplastics in drinking water to human health and help to formulate effective strategies for microplastic monitoring. The existing knowledge of microplastic removal by different treatment processes was also thoroughly discussed. Additionally, the potential challenges of microplastic removal from treatment processes and remediation strategies of microplastics in drinking water were also put forward. The relationship between the properties and behavior of microplastics during different treatment processes is suggested to explore in the future.

Fullerenes possess high chemical stability, large specific surface area, good electrical conductivity and unique three-dimensional structure. In this paper, we provide a general overview of the latest research results of fullerene-based photocatalysts. Firstly, the current status of semiconductor materials and fullerenes in photocatalytic applications are briefly introduced. Secondly, introduced action mechanisms of photocatalysts modified by fullerene C60 and its derivatives, including basic structure, exclusive properties and its effect in photocatalysis and material preparation process. Thirdly, factors affecting material effectiveness and the synthesis strategy of composite photocatalyst modified by fullerene are introduced. Meanwhile, the application advances of the photocatalysts are introduced, including in the degradation of pollutants, organic synthesis, hydrogen production, antibacterial and disinfection in water. Finally, the development trends of fullerenes and their derivatives in photocatalysis are also summarized, including theoretical calculations, the morphological structure control, stable derivatives and increase the selectivity, and new other types of fullerene materials.

In this work, novel photocatalysts Ag3PO4@[email protected] with excellent visible light photocatalytic performance and photostability were successfully prepared by a facile in-situ precipitation method. The optimal catalyst Ag3PO4@0.1%[email protected]%PANI showed the highest photocatalytic performance for degradation of phenol and p-nitrophenol, the apparent rate constant of which was 21.9 and 10 times than that of the pure Ag3PO4, respectively. Interestingly, the Ag3PO4 exhibited significant changes in particle size, which changed from 10 to 20 μm for pure Ag3PO4 particles into 0.38–1.0 μm and 0.15–0.38 μm with the addition of MWCNTs and PANI, respectively. In presence of MWCNTs, similar phenomena have been reported in our previous studies, while the ability of PANI dissolved in the presence of DMF solvent to control the size of Ag3PO4 crystal was reported for the first time. The dramatic enhancement of photocatalytic activity and photostability could be attributed to the synergetic effect between MWCNTs and PANI on Ag3PO4. The MWCNTs penetrating in the bulk phase of Ag3PO4 could serve as conductors of photogenerated electrons and rapidly migrated electrons to the surface of the photocatalysts. Meanwhile, photogenerated holes in the valence band of Ag3PO4 were transferred to the photocatalysts surface through HOMO of PANI. Consequently, high separation efficiency of electron-hole pairs was successfully achieved. A novel design and preparation strategy for photocatalyst was proposed to simultaneously achieve the small size control of catalyst crystal and improve the photocatalytic performance of catalyst by adding MWCNT and PANI.

In this study, the hollow mesoporous carbon spheres (HMCs) were synthesized and modified for laccase (Lac) immobilization, and the structural characteristics of HMCs materials were determined by FESEM, TEM and FTIR etc. The maximum loading of Lac on the HMCs materials could reach 835 mg/g, meanwhile, the immobilized Lac exhibited excellent thermo-stability, pH stability, storage stability and reusability. The antibiotics removal experiments indicated that the immobilized Lac possess efficient removal efficiency for both tetracycline hydrochloride (TCH) and ciprofloxacin hydrochloride (CPH) in the presence of redox mediator. The synergy of the adsorption by HMCs and the degradation by Lac could be the reasons for the high removal of antibiotics. Meanwhile, for investigating degradation mechanism, the degradation product analysis and molecular docking method had been introduced to this study. According to the degradation products, dehydroxylation and demethylation are major degradation reactions for TCH degradation, and the oxidation of the piperazinyl substituent and hydroxylation are the major degradation for CPH degradation. The docking results showed that some important residues played the key role in the degradation process. This study indicated that the immobilization of Lac on HMCs could be potentially applied in environmental remediation of antibiotics.

Herein, the nitrogen-doped hollow mesoporous carbon spheres (N-HMCs) modified g-C3N4/Bi2O3 direct dual semiconductor photocatalyst (g-C3N4/Bi2O3@N-HMCs) were synthesized by a facile thermal process. The morphology, structure, elements, and photoelectrochemical properties of the as-prepared samples were characterized by electron microscopy, N2 sorption–desorption, X-ray diffraction, X-ray photoelectron spectroscopy, diffuse-reflectance spectra, and photoluminescence spectroscopy, among other technologies. The photocatalytic efficiency was evaluated toward degradation of antibiotics tetracycline hydrochloride (TCH) and ciprofloxacin hydrochloride (CFH) under visible-light irradiation, and the results showed that the g-C3N4/Bi2O3@N-HMCs composite exhibited superior photocatalytic efficiency than other comparison samples, which could be attributed to the synergistic action of g-C3N4/Bi2O3 direct dual semiconductor photocatalytic system and the N-HMCs. The characterization techniques revealed that N-HMCs play three vital roles in improving photocatalytic efficiency. First, N-HMCs could serve as a photosensitizer to enhance visible-light absorption. Second, N-HMCs are an excellent conductive material to transfer the photoexcited electrons quickly to hinder the electron–hole pairs recombination. Third, N-HMCs could provide more active sites in the photocatalytic process. The scavenger experiments and electron-spin-resonance results revealed that the active substances h+, •O2–, and •OH performed together in the photodegradation system. Additionally, the g-C3N4/Bi2O3@N-HMCs composite showed favorable photostability after six rounds of recycling, suggesting the great prospects of the practical application of g-C3N4/Bi2O3@N-HMCs.

Researches on metal-organic framework (MOF) materials have gathered increasing interest in the field of photocatalysis due to their large surface area, well-ordered porous structure, and tunable organic bridging linker/metal clusters with a tailorable capacity to absorb light. The development of inexpensive, stable, efficient, and band-gap tunable MOF-based photocatalysts is still a great challenge. The selection of central metal ions and organic ligands is of great importance for the fabrication of MOFs with excellent photocatalytic properties. This review aimed to summarize the strategies of improving photocatalytic activity under light illumination, including optimization, modification, doping and imperfection, mainly in structure, light absorption, band gap and stability. In addition, the applications of various modified MOFs are also introduced. Finally, the future developments of MOFs are discussed.

Abstract The large volume expansion induced by K + intercalation is always a big challenge for designing high‐performance electrode materials in potassium‐ion storage system. Based on the idea that large‐sized ions should accommodate big “houses,” a facile‐induced growth strategy is proposed to achieve the self‐loading of MoS 2 clusters inside a hollow tubular carbon skeleton (HTCS). Meantime, a step‐by‐step intercalation technology is employed to tune the interlayer distance and the layer number of MoS 2 . Based on the above, the ED‐MoS 2 @CT hybrids are achieved by self‐loading and anchoring the well‐dispersed ultrathin MoS 2 nanosheets on the inner surface of HTCSs. This unique compositing model not only alleviates the mechanical strain efficiently, but also provides spacious “roads” (hollow tubular carbon skeleton) and “houses” (interlayer expanded ultrathin MoS 2 sheets) for fast K + transition and storage. As an anode of potassium‐ion batteries, the resultant ED‐MoS 2 @CT electrode delivers a high specific capacity of 148.5 mAh g −1 at 2 A g −1 after 10 000 cycles with only 0.002% fading per cycle. The assembled ED‐MoS 2 @CT//PC potassium‐ion hybrid supercapacitor device shows a high energy density of 148 Wh kg −1 at a power density of 965 W kg −1 , which is comparable to that of lithium‐ion hybrid supercapacitors.

Metal organic frameworks (MOFs) are one set of the most excellent supports for Pd nanoparticles (NPs). MOFs as the host mainly have the following advantages: (i) they provide size limits for highly dispersed Pd NPs; (ii) fixing Pd NPs is beneficial for separation and reuse, avoiding the loss of expensive metals; (iii) the MOFs skeleton is diversified and functionalized, which is beneficial to enhancing the interaction with Pd NPs and prolonging the service life of the catalyst. This review discusses the synthesis strategy of Pd@MOF, which provides guidance for the synthesis of similar materials. After that, the research advance of Pd@MOF in heterogeneous catalysis is comprehensively summarized, including C-C coupling reaction, benzyl alcohol oxidation reaction, simple olefin hydrogenation reaction, nitroaromatic compound reduction, tandem reaction, and the photocatalysis, with the emphasis in providing a comparison with the performance of other alternative Pd-containing catalysts. In the final section, this review presents the current challenges and which are the next goals in this field.

Currently, the pollution of metals and metalloids in the soil has attracted considerable attention. Phytoremediation is considered an environmentally friendly means of remediating pollution, but often takes a long time to perform. Therefore, the combination of plants and nanomaterials in environmental management has attracted the attention of many researchers because some nanomaterials can promote the germination of plant seeds and the growth of whole plants. However, when the concentration of nanomaterials is not controlled properly, certain toxicity will be produced. This paper reviews research on the combination of plant and nanomaterials for the remediation of contaminated environments, as well as on the effects of nanomaterials on plants.

N-doped carbon materials have been proven to be effective catalysts for activating peroxymonosulfate (PMS). Marine algae biomass is rich in nitrogenous substances , which can reduce the cost of N-doping process and can obtain excellent N-doped catalysts cheaply and easily. In this study, kelp biomass was selected to prepare N-doped kelp biochar (KB) materials. The high defect degree, high specific surface area, and participation of graphite N make KB have excellent catalytic degradation ability. The KB degraded 40 mg/L ofloxacin (OFL) close to 100% within 60 min, applied with PMS. Through quenching experiments and electron paramagnetic resonance spectroscopy, the degradation process dominated by non-radical pathways was determined. At the same time, O2·- and 1O2 were closely related, and a significant impact of quenching O2·- on the reaction was observed. The non-radical approach made the system excellent performance over a wide pH range and in the presence of multiple anions. The experiments of reusability confirmed the stability of the material. Its catalytic performance was restored after low-temperature pyrolysis. This research supports the use of endogenous nitrogen in biomass. It provides more options for advanced oxidation process application and marine resource development.

Extracellular polymeric substances (EPS) with high molecular weights, secreted from microorganisms, play a critical functional role in the aerobic granular sludge (AGS). To investigate the level and function of EPS during the granulation of aerobic sludge and in the mature AGS, a sequencing batch reactor (SBR) was operated for 70 days. Aerobic granules with an average diameter of 0.25 mm were obtained with reducing settling time of sludge. Simultaneous removals of COD, nitrogen and phosphorus by the mature AGS exceeded 90, 95 and 95%, respectively. The EPS content increased significantly to above 333 mg/g MLVSS during the initial stage, and after that, it stabilized at about 240 mg/g MLVSS as the mature AGS formed, higher than that of the seed sludge (212 mg/g MLVSS). The increased EPS contents showed a negative correlation with SVI values, while a strong positive relationship with the formation of the AGS. The protein/polysaccharide (PN/PS) ratio in the EPS increased from 1.42 to 4.17, and TP/MLSS increased to about 6%, with the formation of AGS. The proportion of extracellular-P increased with the increase of EPS, and then maintained stable at about 20%, indicating EPS promoted the removal of phosphorus. Furthermore, the results from the Standards, Measurements and Testing (SMT) and X-Ray Diffraction (XRD) showed that phosphorus in the AGS mainly existed in the form of inorganic phosphorus (IP) and the proportion of Ca5(PO4)3(OH) in IP was up to 92%. This investigation demonstrated that EPS had a positive relationship with the sludge granulation and nutrients removal.

Abstract The objective of this study was to establish baseline concentrations for 15 potentially toxic elements (Ag, As, Ba, Be, Cd, Cr, Cu, Hg, Mn, Mo, Ni, Pb, Sb, Se, and Zn) based on 448 representative Florida surface soils using microwave assisted HNO 3 ‐HCl‐HF digestion. Baseline concentrations of those elements were (mg kg −1 ): Ag 0.07–2.50, As 0.02–7.01, Ba 1.67–112, Be 0.04–4.15, Cd 0–0.33, Cr 0.89–80.7, Cu 0.22–21.9, Hg 0.00075–0.0396, Mo 0.13–6.76, Ni 1.70–48.5, Pb 0.69–42.0, Sb 0.06–0.79, Se 0.01–1.11, and Zn 0.89–29.6, respectively. Upper baseline values for most elements corresponded with these reported in literature, except Ba, Hg, Mn, Sb, and Zn, which were 3 to 23 times lower. Soil properties, including pH, organic carbon (OC), particle size, cation‐exchange capacity (CEC), available water, extractable base, extractable acidity, total Ca, Mg, P, K, Fe, and Al concentrations, were related to metal concentrations using factorial analysis. Eight factors were identified (total Fe and Al, CEC, pH, clay, OC, total Ni and Mo, total Sb and Pb, and total Hg) and accounted for 87% of the total variance, suggesting that metal concentrations were primarily controlled by soil compositions. Multiple regression of elemental concentrations against total Fe, total Al, clay, OC, CEC, and pH was significant for all elements. Partial correlation coefficients indicated that total Fe and/or Al explained most of the variance for Mn, Ni, Ba, Be, Hg, As, Cd, Cr, Cu, Mo, Pb, and Zn concentrations. Most of the variance in Se was related to clay, whereas those of Ag and Sb related to clay and total Al.

To assess the efficiency of P-induced metal immobilization in soils, a pilot-scale field experiment was conducted at a metal contaminated site located in central Florida. Phosphate was applied at a P/Pb molar ratio of 4.0 with three treatments: 100% of P from H3PO4, 50% of P from H3PO4+ 50% of P from Ca(H2PO4)2, and 50% of P from H3PO4+5% phosphate rock in the soil. Approximately 1 year after P application, soil and plant samples were collected to determine mobility and bioavailability of selected metals (Pb, Zn, and Cu) using sequential extraction procedure and mineralogical characterization using X-ray diffraction (XRD) and scanning electron microscope-energy dispersive X-ray (SEM-EDX) analysis. Phosphorus distribution and soil pH effects were also evaluated. Phosphate was more effective in transforming soil Pb (to 53%) from the non-residual to the residual phase than soil Zn (to 15%) and soil Cu (to 13%). This was because Pb was immobilized by P via formation of an insoluble pyromorphite-like mineral in the surface and subsurface of the soil, whereas no phosphate mineral Zn or Cu was identified. While P amendment enhanced metal uptake in the roots of St. Augustine grass (Stenotaphrum secundatum), it significantly reduced metal translocation from root to shoot, especially Pb via formation of a pyromorphite-like mineral on the membrane surface of the root. A mixture of H3PO4 and phosphate rock was effective in metal immobilization, with less soil pH reduction and less soluble P. Although H3PO4 was effective in immobilizing Pb, its use should be limited to minimize soil pH reduction and potential eutrophication risk.

The presence of heavy metals in municipal sludge restricts its use for agricultural purposes. In this paper, the bioavailability and eco-toxicity of heavy metals in municipal sludge was evaluated, taking into consideration both the speciation of metals and the local environmental characteristics. The dewatered municipal sludge samples were collected from five sewage plants in Changsha, Zhuzhou and Xiangtan respectively, which are representative cities with characteristics of the middle-south region of China. Some agricultural significant parameters and total metal concentrations in the sludge were determined and the metal speciation was studied by using BCR sequential extraction procedure. It was found experimentally that in general the municipal sludge collected from the five sewage plants was rich in organics, N and P. Except that the sludge from Xia Wan Sewage Treatment Plant showed higher concentrations of heavy metals, the sludge from other plants all showed a low total content of heavy metals with only Cd slightly exceeding the permitted values of the national application standard of acid soil in China (GB18918-2002). The sequential extraction results showed that Cu and Zn were principally distributed in the oxidizable fraction, which meant a high potential toxicity, but the bioavailability of Zn might be overestimated to the soil of Hunan. Pb was mainly in the residual fraction. The distribution of Cd showed no obvious characteristics.

Lead contamination at shooting range soils is of great environmental concern. This study focused on weathering of lead bullets and its effect on the environment at five outdoor shooting ranges in Florida, USA. Soil, plant, and water samples were collected from the ranges and analyzed for total Pb and/or toxicity characteristic leaching procedure (TCLP) Pb. Selected bullet and berm soil samples were mineralogically analyzed with X-ray diffraction and scanning electron microscopy. Hydrocerussite [Pb3(CO3)2(OH)2] was found in both the weathered crusts and berm soils in the shooting ranges with alkaline soil pH. For those shooting ranges with acidic soil pH, hydrocerussite, cerussite (PbCO3), and small amount of massicot (PbO) were predominantly present in the weathered crusts, but no lead carbonate mineral was found in the soils. However, hydroxypyromorphite [(Pb10(PO4)6(OH)2] was formed in a P-rich acidic soil, indicating that hydroxypyromorphite can be a stable mineral in P-rich shooting range soil. Total Pb and TCLP Pb in the soils from all five shooting ranges were significantly elevated with the highest total Pb concentration of 1.27 to 4.84% (w/w) in berm soils. Lead concentrations in most sampled soils exceeded the USEPA's critical level of 400 mg Pb kg(-1) soil. Lead was not detected in subsurface soils in most ranges except for one, where elevated Pb up to 522 mg kg(-1) was observed in the subsurface, possibly due to enhanced solubilization of organic Pb complexes at alkaline soil pH. Elevated total Pb concentrations in bermudagrass [Cynodon dactylon (L.) Pers.] (up to 806 mg kg(-1) in the aboveground parts) and in surface water (up to 289 microg L(-1)) were observed in some ranges. Ranges with high P content or high cation exchange capacity showed lower Pb mobility. Our research clearly demonstrates the importance of properly managing shooting ranges to minimize adverse effects of Pb on the environment.

Abstract Development of new aggregation‐induced emission (AIE) luminogens has been a hot research topic because they thoroughly solve the notorious aggregation‐caused quenching effect confronted in conventional fluorogens and their promising applications in, for example, organic light‐emitting diodes, chemo‐ and biosensors and bioimaging. Many AIE luminogens (AIEgens) have been prepared but most of them are silole, tetraphenylethene, distyrylanthracene, and their derivatives. In this work, based on the skeleton of tetraphenylpyrazine (TPP), a new AIEgen, named TPP‐PDCV, is generated by functionalizing TPP with malonitrile group. TPP‐PDCV can serve as a sensitive ratiometric fluorescent probe for detecting hydrogen sulfide with high speciality and low detection limit of down to 0.5 × 10 −6 m . The mechanism for such detection is fully investigated and deciphered. Unlike most reported mechanochromic AIEgens, which undergo turn‐off or ‐on emission or emission bathochromic shift in the presence of external stimuli, TPP‐PDCV exhibits an abnormal and reversible mechanochromism with hypsochromic effect. These indicate that TPP‐PDCV possesses a huge potential for high‐tech applications through rational modification of TPP core.

An amphiphilic pillar[5]arene (AP5) was modified onto the surface of reduced graphene oxide (RGO) to form the water-dispersive RGO-AP5 nanocomposite. And then, as-prepared gold nanoparticles (AuNPs) self-assembled onto the surface of RGO-AP5 through amido groups of AP5 to achieve RGO-AP5-AuNPs nanocomposites. It was verified that a large amount of AP5 molecules had been effectively loaded onto the surface of RGO and lots of AuNPs could be uniformly dispersed on RGO-AP5. Electrochemical results showed that the RGO-AP5 could exhibit selective supramolecular recognition and enrichment capability toward guest molecules. More significantly, in electrochemical sensing the guest molecules, ternary nanocomposites RGO-AP5-AuNPs performed the synergetic action of multifunctional properties, which were excellent performances of RGO, selective supramolecular recognition, and enrichment capability of AP5 and catalytic property of AuNPs for guest molecules. Therefore, RGO-AP5-AuNPs showed an outstanding analyzing performance for DA with broad linear range (1.5 × 10–8 to 1.9×10–5 M) and low detection limit (1.2 × 10–8 M) at a signal-to-noise ratio of 3.

The occurrence of 13 veterinary drugs were studied in soil fertilized with animal manures in Eastern China. The 69 soil samples were obtained from twenty-three vegetable fields in 2009 and analysed for selected veterinary drugs by HPLC–MS/MS at soil depths of 0–20, 20–40 and 40–60 cm, and two additional samples were re-analysed from an earlier study from November 2011. Results showed that animal wastes, especially those from poultry farms, were one of pollution sources of veterinary drugs in soil. The detection frequency of veterinary drugs in soil was 83%, 91% and 87% in the three soil depths, respectively. The detection rates for the five classes of drugs in soils followed the rank order cyromazine > tetracyclines > sulfonamides > fluoroquinolones > florfenicol. Veterinary drugs were detected in soil layers at 20–40 and 40–60 cm depth to a greater extent than at 0–20 cm depth. The results of the same point in years 2009 and 2011 indicated that veterinary drugs accumulate easily and persist in the deeper soil. In addition, residue levels of veterinary drugs in soil were related to the animal species the manure was derived from. Overall, the predominance of tetracyclines in sampled soils underscored the need to regulate their veterinary use in order to improve the management and treatment of associated releases.

Semiconductor photocatalysis is an extremely promising technology to deal with the far-reaching issues we need to face, such as the shortage of renewable-energy resources and the increasingly serious worldwide environmental problems. Ag3PO4 is an excellent visible-light-driven photocatalyst, showing an extraordinary photoactivity for oxygen evolution in water splitting and degradation of pollutant in aqueous solution. However, due to the uncontrollable photocorrosion phenomenon, the Ag3PO4-based photocatalysis is still at laboratory scale. To remove the obstacles for practical application and to further improve its photocatalytic performance, this review summarized the achievements that have been made in this field. We began with an effort to introduce the reasons for Ag3PO4 exhibiting excellent photocatalytic performance. Subsequently, the different synthesis methods of Ag3PO4 were discussed. Finally, we outlined the barriers that hindered the practical application of Ag3PO4 and proposed the ways to remove these barriers. This review also underlined the crucial problems that should be addressed prior to practical applications.

The treatment of wastewater containing hydrophobic organic pollutants solubilized by surfactants is of great environmental importance. In this work, the removal of rhamnolipid-solubilized hexadecane via a salicylic acid-methanol-acetone modified steel converter slag (SMA-SCS) catalyzed Fenton-like process was studied. First, we investigated the adsorption of rhamnolipid and hexadecane onto SCS and SMA-modified SCS. Compared to that of SCS, SMA-SCS exhibited better adsorption performance with maximum adsorption capacities of 0.23 and 0.28 mg/g for hexadecane and rhamnolipid, respectively. Degradation experiments showed that hexadecane was more readily degraded by the Fenton-like process than rhamnolipid. Up to 81.1% of hexadecane removal was achieved over 20 g/L of SMA-SCS within 24 h, whereas only 36% of rhamnolipid was degraded. On the other hand, the results indicated that increased rhamnolipid concentration had a negative effect on the degradation of hexadecane. During the oxidation reaction, the pH value of solution remained between 6.0 and 6.72. All these results demonstrated that the SMA-SCS/H2O2 Fenton-like process could be a cost-effective and promising approach for the treatment of surfactant-solubilized hydrophobic organic compounds.

Reduced graphene oxide (rGO) modified with three kinds of water-soluble p-sulfonated calix[4,6,8]arene sodium (SCn: SC4, SC6, SC8) were successfully prepared by using a simple wet chemical strategy. Three obtained SCn-rGO nanocomposites were characterized by Fourier transform infrared spectroscopy, Ultraviolet–visible spectroscopy, static contact angle measurement, thermogravimetric analysis, scanning electron microscope and electrochemical impedance spectroscopy, which confirmed that different amount of SCn molecules had been effectively loaded onto the surface of rGO, and the water-dispersity and stability of SCn-rGO increased with the increase of the value of n in SCn (n = 4, 6, 8). More significantly, cyclic voltammetry measurement showed that the SCn-rGO could exhibit high supramolecular recognition and enrichment capability and consequently displayed excellent electrochemical response toward four probe molecules (biological and organic dye molecules). Especially, SC8-rGO exhibited an excellent electrochemical performance for dopamine with high current densities of 73.04 mA mM–1 L cm–2, broad linear range (1 × 10–8 to 2.1 × 10–5 M) and very low detection limit (8 × 10–9 M) at a signal-to-noise ratio of 3.

Soil pollution has been an environmental problem drawing worldwide attention. Phytoremediation is a good and highly accepted method for treating contaminated soil. Numerous studies have been performed to enhance the phytoremediation efficiency by various approaches. The development of nanotechnology provides an effective alternative method. This article reviews recent advances in using nanomaterials to facilitate the phytoremediation of contaminated soil. Nanomaterials can function in the phytoremediation system through directly removing pollutants, promoting plant growth, and increasing pollutant phytoavailability. Phytoextraction is the most effective and recognized phytoremediation strategy for remedying contaminated soil. Nanoscale zero-valent iron is the most studied nanomaterials for facilitating the phytoremediation due to its successful engineering applications in treating contaminated soil and groundwater. Fullerene nanoparticles can increase the phytoavailability of pollutant. In general, using nanomaterials to facilitate the phytoremediation of contaminated soil can be an effective strategy, but it is still in the phase of exploration and attempt. The experience from more application cases is required and the long-term performance of nanomaterials in phytoremediation systems needs further research.

Boron (B), normally present in ground water and sea water, is a vital micronutrient for plants, but is also toxic in excessive amounts. Under typical conditions, aqueous boron is present as boric acid (H3BO3), which is uncharged, making B particularly challenging to remove by mechanisms commonly applicable to removal of trace constituents. Adsorption of B onto aluminum hydroxide solids (Al(OH)3(s)) generated using aluminum-based electrocoagulation (EC) is a promising strategy for B removal. Infrared spectroscopy analysis indicated complexation of B(OH)3 with aluminum hydroxide solids via surface hydroxyl groups, while X-ray and infrared spectroscopy results indicated that the structure of the Al(OH)3(s) was influenced both by EC operating conditions and by water quality. A linear adsorption model predicted B removal well when initial concentrations were lower than 50 mg/L, but fit the experimental data poorly at higher initial B concentrations. The Langmuir adsorption model provided a good fit for a broader range of initial B concentrations (5–1000 mg/L). Factors affecting B adsorption during the EC process, including current intensity, Al dissolution rate, boron concentration, pH, and total dissolved solid (TDS), were investigated. Increasing current intensity initially led to a higher Al dissolution rate, and therefore higher B adsorption, but there was a limit, as further increases in current intensity caused rapid formation of Al(OH)3(s) having a large particle size and a low capacity to complex B. Boron removal decreased as its concentration increased. The best removal of B occurred at pH 8, corresponding to a slightly positive zeta potential for aluminum hydroxide and a small but significant fraction of negatively charged B species. Higher TDS concentrations facilitated the use of higher current intensities, i.e., the limit on the effective Al dissolution rate increased with increasing TDS. Two real water samples (river water and oilfield produced water) spiked with B were treated using EC, resulting in up to 50% B removal from river water (C0 = 10 mg/L, current = 0.2 A) in 2 h, and 80% B removal from produced water (C0 = 50 mg/L, current = 1.0 A) in 2 h.

Airborne particulate matter (PM) has been a major threat to air quality and public health in major cities in China for more than a decade. Green space has been deemed to be effective in mitigating PM pollution; however, few studies have examined its effectiveness at the neighborhood scale. In this study, the authors probe the contributions from different landscape components in the green space (i.e., tree, grass), as well as the spatial scale of planning on fine PM (PM2.5) concentrations in urban neighborhoods. PM2.5 data including 37 samples from five megacities were collected from the National Environmental Monitoring Centre in China. Results showed that, neighborhood green space greatly contributed to the spatial variation in PM2.5. The total green space coverage, tree coverage, and grass coverage were all negatively correlated with PM2.5 concentration (p < 0.05). The higher green space coverage the site had, the lower the daily mean, daily minimum, and daily maximum of PM2.5 concentration were there. Tree coverage, in particular, was effective in reducing the PM2.5 concentrations, and, more importantly, its effectiveness was more significant with the higher ambient PM2.5 level. According to the examination on the effect of spatial scale, the capability for a neighborhood green space to attenuate PM2.5 pollution would be vanished when its size smaller than 200 m, and would be maximized when its size within 400–500 m. These results will contribute to the evidence-based design and management of green space to mitigating urban PM pollution.

The unique physicochemical properties of fullerenes are to a great extent determined by their purity. Pure fullerenes separated from fullerene soot are currently promising nanomaterials for versatile potential applications. But there are few efficient methods to obtain fullerenes in pure form, most of fullerene properties remain unclear. To gain their optimal properties in potential applications, more efficient methods to separate pure fullerenes are supposed to develop. One of the most active researches in fullerene separation is to find suitable receptors to bind fullerenes and then release them through host–guest interactions based on supramolecular chemistry to obtain pure products. So this review highlights the recent advances in the design of molecular receptors that feature corresponding size, shape or electronic complementary to fullerenes as the primary recognizing factor. The method using designed molecular receptors for fullerene separation here is called as selective complexation technology. And some designed polymers that can be used as supports to achieve fullerene selective separation via reversible Diels-Alder addition are also described. Besides, other two common practical separation methods, improved chromatography and fractional crystallization, are presented. All separation methods mentioned in this review can achieve selective fullerene separation with recycling process and no special equipment, which conform to the requirement of environment friendly development in 21st century. Each method has its own characteristic depending on the applied fields. Our purpose is to show the readers efficient designed methods exploitable for scalable preparation of high-quality pure fullerenes and stimulate their boarder potential applications.

Abstract Currently, the development of aggregation‐induced emission (AIE) luminogens (AIEgens) has enabled us to “see” never before seen scenery. However, not all AIEgens exhibit the impressive emission efficiency in aggregated states. Moreover, the emission color of AIEgens can be seriously affected when their performance is improved. Therefore, to overcome this limitation, an efficient method is proposed here through the tailored alkyl linkages to greatly improve the emission efficiency of tetraphenylethene (TPE)‐based AIEgens but retain their emission color. Encouragingly, significantly enhanced emission efficiency is achieved with the quantum yield up to 68.19% and 65.20% for BTPE‐C4 and BTPE‐C8, respectively, in contrast to that of TPE (25.32%), demonstrating the proverb that one plus one is much larger than two (1 + 1 &gt;&gt; 2). Interestingly, when alkyl linkages in skeletons are fine‐tuned, self‐assembled nanorods, nanosheets, and nanofibers are successfully achieved for BTPE‐C1, BTPE‐C4, and BTPE‐C8 in tetrahydrofuran and water system. Also, these developed emissive AIEgens not only exhibit impressive response to the environmental stimuli of mechanical force, viscosity, temperature, and light, but can also be used to dynamically monitor and control the phase‐separated morphology in polymeric blends.

In the past few decades, many emerging pollutants have been detected and monitored in different water sources because of their universal consumption and improper disposal. Among these, endocrine-disrupting chemicals (EDCs), a group of organic chemicals, have received global attention due to their estrogen effect, toxicity, persistence and bioaccumulation. For the removal of EDCs, conventional wastewater treatment methods include flocculation, precipitation, adsorption, etc. However, there are some limitations on these common methods. Herein, in order to enhance the public’s understanding of environmental EDCs, the definition of EDCs and the characteristics of several typical EDCs (physical and chemical properties, sources, usage, concentrations in the environment) are reviewed and summarized in this paper. In particular, the methods of EDC removal are reviewed, including the traditional methods of EDC removal, photocatalysis, biodegradation of EDCs and the latest research results of EDC removal. It is proposed that photocatalysis and biodegradation could be used as an environmentally friendly and efficient EDC removal technology. Photocatalytic technology could be one of the water treatment methods with the most potential, with great development prospects due to its high catalytic efficiency and low energy consumption. Biodegradation is expected to replace traditional water treatment methods and is also considered to be a highly promising method for efficient removal of EDCs. Besides, we summarize several photocatalysts with high catalytic activity and some fungi, bacteria and algae with strong biodegradability.

Montmorillonite (Mt) has been used widely for metal removal from water and wastewater due to its various advantages including low cost, large surface area, high structure stability, and high ion exchange capacity. However, the removal of anionic hexavalent chromium (Cr) using Mt is inhibited by the negative charges on the adsorbent. To enhance Cr (VI) adsorption on Mt, a cationic surfactant – cetylpyridinium chloride (CPC) – was utilized to modify the interlayer surface of Mt. Fourier-transform infrared spectroscopy and X-ray diffraction were performed to characterize the CPC modified Mt (CPC-Mt) and the structure change of Mt. Studies have shown that CPC intercalated into Mt interlayers via electrostatic interaction between Mt and CPC, as well as the hydrophobic interaction among CPC molecules. After modification, the CPC-Mt showed a positive zeta potential at pH 2–11; while the specific surface area decreased, CPC effectively increased the interlayer distance of Ca-Mt, with a maximum d001 value of 4.37 nm, and provided more exchange sites for Cr (VI) adsorption. Cr (VI) was efficiently removed using CPC-Mt at low pH values, but the removal was influenced adversely by the increase of pH and ionic strength. The adsorption process was described by a Langmuir isotherm model with the constant of 0.342 L/mg and the maximum adsorption capacity of 43.84 mg/g at 298 K, and by a pseudo-second order kinetic model with a kinetic coefficient of 6.62 g/(mg·min). The adsorption mechanism analysis has shown that electrostatic attraction is the main mechanism for Cr (VI) removal; at the same time, the reduction of Cr (VI) to Cr (III) by Fe (II) in Mt cannot be neglected at low pH values, which increased Cr removal and was confirmed by the X-ray photoelectron spectroscopic analysis.

To enhance the removal of dyes from water, the adsorption capacity of an adsorbent can usually be increased via reducing its particle size and enlarging the specific area. To this end, a reverse micro-emulsion system was developed in this study using an ionic liquid ([C14MIm]Cl) to prepare nanoscale zeolitic imidazolate framework-8 (ZIF-8) material for Congo red (CR) anionic dye separation from water. The size and morphology of nano ZIF-8 synthesized under different conditions, including reaction time, the order of reactants addition, the molar ratio of water and [C14MIm]Cl and the concentration of reactants, were analyzed by dynamic light scattering (DLS) particle size analyzer and transmission electron microscope (TEM). The optimal synthesis conditions including reaction time of 60 min, the ratio of water and ionic liquid (ω0) of 60, and the concentrations of B1 and B2 solutions of 0.07 M and 0.28 M, were determined using the response surface method (RSM). Studies have shown that the reverse micro-emulsion system can effectively control the crystal size of ZIF-8 nanoparticles, with a uniform particle size distribution from 15 to 35 nm, smaller than that of the general ZIF-8 material prepared in the aqueous phase (100–200 nm). The specific surface area of the nano ZIF-8 particles synthesized under optimal synthesis conditions was 1477 m2/g. The synthesized nano ZIF-8 material removed Congo red (CR) dye from water efficiently by adsorption. Congo red adsorption on nano ZIF-8 was observed as a spontaneous endothermic adsorption process. The adsorption conformed to the pseudo-second-order kinetic model and the Langmuir isotherm model. The maximum predicted adsorption amount was 1339.8 mg/g at a temperature of 323 K. Analysis of adsorption mechanism shows that the adsorption of CR on nano ZIF-8 materials is mainly due to electrostatic interaction and physical attraction including hydrogen bonds and π-π bond interactions. This study further expands the application of reverse micro-emulsion method in nanoscale framework materials preparation.

The aggregation of MoS2 nanoparticles and inefficient electron-migration limit their application for antibiotic removal. In this study, pomelo peel biochar (BC) with smooth surface structure was used as the matrix for loading nano-flower-like MoS2 microspheres. The as-prepared nanocomposites were used to improve the removal efficiency of ciprofloxacin (CIP). A series of characterizations revealed that the optimal weight ratio of BC to MoS2 was 3:35 (MoS2-BC3/35). MoS2-BC3/35 with narrow-bandgap (1.60 eV) possessed efficient light-utilization ability and the photodegradation efficiency toward CIP was 92.01%, whereas the CIP removal efficiency by MoS2 was 44.50%. The improvement of this efficiency was attributed to the reduction of electron-hole pairs recombination. More attractively, superoxide radical (·O2−) played a major role during the photocatalytic reaction, because the conduction band potential of MoS2-BC3/35 (-0.81 eV) is lower than the potential of O2/·O2− (-0.33 eV). Overall, MoS2-BC3/35 is a promising photocatalyst owing to its eco-friendliness, high-efficiency and easy-preparation.

Biochar is advocated as an environment-friendly and cost-effective material for removing both heavy metals and organic contaminants in soil remediation. However, our understandings on the cotransport potential of contaminants with the nanoscale biochar downward along soil profiles (e.g., potential environmental risks towards groundwater) remain largely unknown. This study investigated the effects of wheat straw-derived biochar nanoparticles pyrolyzed at 350 °C and 500 °C (BNP350 and BNP500) on the transport of cadmium (Cd(II)) in water-saturated soil packed columns. Different ionic strengths (ISs) without/with humic acid (HA) were tested to mimic the scenarios during soil remediation. BNPs could act as a vehicle mediating Cd(II) transport in soils. At a low IS (1.0 mM KCl), compared to the limited transport of individual Cd(II), BNP500 enhanced (69 times) Cd(II) transport (Cd(II) mass recovery (M) = 7.59%) in soils, which was greater than that by BNP350 (54 times, M = 5.92%), likely due to the higher adsorption of Cd(II) onto BNP500. HA further increased the Cd(II) transport by BNPs (M = 8.40% for BNP350 and M = 11.95% for BNP500), which was mainly due to the increased mobility of BNPs carrying more absorbed Cd(II). In contrast, at a high IS (10 mM KCl), BNP500 dramatically inhibited the transport of Cd(II) (M = 12.9%), decreasing by about 61.6%, compared to the BNPs absence (M = 33.6%). This is because a large amount of BNP500-Cd(II) was retained in soils at a high IS. This inhibition effect of Cd(II) transport by BNPs was reinforced with the presence of HA. Our findings suggest that the pyrolysis temperature of biochar should be carefully considered when applying biochar for in-situ remediation of soils contaminated by heavy metals such as Cd(II) under various organic matter and IS conditions.

Abstract It is critical to compare existing sample digestion methods for evaluating soil contamination and remediation. USEPA Methods 3050, 3051, 3051a, and 3052 were used to digest standard reference materials and representative Florida surface soils. Fifteen trace metals (Ag, As, Ba, Be, Cd, Cr, Cu, Hg, Mn, Mo, Ni, Pb, Sb, Se, and Zn), and six macro elements (Al, Ca, Fe, K, Mg, and P) were analyzed. Precise analysis was achieved for all elements except for Cd, Mo, Se, and Sb in NIST SRMs 2704 and 2709 by USEPA Methods 3050 and 3051, and for all elements except for As, Mo, Sb, and Se in NIST SRM 2711 by USEPA Method 3052. No significant differences were observed for the three NIST SRMs between the microwave‐assisted USEPA Methods 3051 and 3051a and the conventional USEPA Method 3050 except for Hg, Sb, and Se. USEPA Method 3051a provided comparable values for NIST SRMs certified using USEPA Method 3050. However, for method correlation coefficients and elemental recoveries in 40 Florida surface soils, USEPA Method 3051a was an overall better alternative for Method 3050 than was Method 3051. Among the four digestion methods, the microwave‐assisted USEPA Method 3052 achieved satisfactory recoveries for all elements except As and Mg using NIST SRM 2711. This total‐total digestion method provided greater recoveries for 12 elements Ag, Be, Cr, Fe, K, Mn, Mo, Ni, Pb, Sb, Se, and Zn, but lower recoveries for Mg in Florida soils than did the total‐recoverable digestion methods (3050, 3051, and 3051a).

ADVERTISEMENT RETURN TO ISSUEPREVCommunication to the...Communication to the EditorNEXTPolystyrene-block-poly(vinyl acetate) through the Use of a Switchable RAFT AgentMassimo Benaglia‡, Ming Chen†, Yen K. Chong†, Graeme Moad*†, Ezio Rizzardo*†, and San H. Thang*†View Author Information† CSIRO Molecular and Health Technologies, Bag 10, Clayton South, Victoria 3169, Australia‡ ISOF-CNR, Area della Ricerca, Via P. Gobetti 101, 40129 Bologna, Italy*Corresponding authors. E-mail: [email protected] (G.M.), [email protected] (E.R.), [email protected] (S.H.T.).Cite this: Macromolecules 2009, 42, 24, 9384–9386Publication Date (Web):November 16, 2009Publication History Received22 September 2009Revised5 November 2009Published online16 November 2009Published inissue 22 December 2009https://doi.org/10.1021/ma9021086Copyright © 2009 American Chemical SocietyRIGHTS & PERMISSIONSArticle Views3276Altmetric-Citations108LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit Read OnlinePDF (998 KB) Get e-AlertsSupporting Info (1)»Supporting Information Supporting Information SUBJECTS:Monomers,Organic compounds,Polymerization,RAFT polymerization,Radical polymerization Get e-Alerts

Previous works have demonstrated that ligninolytic enzymes mediated effective degradation of lignin wastes. The degrading ability greatly relied on the interactions of ligninolytic enzymes with lignin. Ligninolytic enzymes mainly contain laccase (Lac), lignin peroxidase (LiP) and manganese peroxidase (MnP). In the present study, the binding modes of lignin to Lac, LiP and MnP were systematically determined, respectively. Robustness of these modes was further verified by molecular dynamics (MD) simulations. Residues GLU460, PRO346 and SER113 in Lac, residues ARG43, ALA180 and ASP183 in LiP and residues ARG42, HIS173 and ARG177 in MnP were most crucial in binding of lignin, respectively. Interactional analyses showed hydrophobic contacts were most abundant, playing an important role in the determination of substrate specificity. This information is an important contribution to the details of enzyme-catalyzed reactions in the process of lignin biodegradation, which can be used as references for designing enzyme mutants with a better lignin-degrading activity.

Complexing metal cations with water-soluble nano-sized ionic polyelectrolytes, combined with a separation process such as ultrafiltration (UF), is a potential strategy to remove or recover ionic heavy metals from water or wastewater. However, competition from naturally occurring cations (e.g., Na+, K+, Ca2+ and Mg2+) may adversely influence target cation removal. To investigate this competition effect, the affinities of both common aqueous cations commonly found in natural surface waters, groundwaters or wastewaters and toxic cationic metals for a typical, commercially available anionic polyelectrolyte, poly(sodium 4-styrenesulfonate) (PSS), were evaluated using a simple ion exchange model and a binary-system ultrafiltration process. Selectivity of these cations for PSS complexation decreased in the order Ba2+ > Pb2+ > Sr2+ > Ca2+ > Cu2+ > Co2+ > Ni2+ > Mg2+ > H+ > K+ > Na+ > Li+. For cations with same valence, their affinity for PSS is proportionally related to their ionic radii. Competitive interactions among different cations complexing with PSS were also investigated in a multi-ion experimental system and the results were compared with estimates obtained using a simple model based on binary-system selectivity coefficients and mass balances. The cation distribution observed in the experimental multi-ion system was consistent with the model calculations. Experimental results also indicate the model can be applied to predict heavy metal (Cu2+ and Pb2+) removal by PSS-assisted UF in a competitive multi-cation water environment. Greater removal of heavy metals was observed at higher ratios of PSS molecular weight to membrane molecular weight cut-off (MW/MWCO).

Laccases or laccase-like multicopper oxidases (LMCOs) could catalyze the oxidation of various substrates coupled to the reduction of oxygen to water. In this study, eight strains with laccase activity were isolated from composting samples in different phases, among which strain C1 isolated from the thermophilic-phase sample presented the highest laccase activity. The purified LMCO of strain C1 showed a single protein band on SDS-PAGE gel with a molecular mass of about 38 kDa. The novel laccase showed alkaline resistance and moderate thermostability. The enzyme activity was activated by some metal ions such as Cu2+, Co2+ and Fe3+ at the concentration of 1 mM, while was strongly inhibited in the presence of Hg2+. The LMCO could efficiently decolorize the indigo carmine and diamond black PV with syringaldehyde as mediator, which suggested a great potential for dye decolorization in the textile industry. The novel strain was identified as Streptomyces sp. C1. The finding of new laccase-producing Streptomyces sp. C1 in this study will also contribute to the further explanation of the function of Actinomycetes in the thermophilic phase of composting.

In this study, a novel nanoadsorbent (Fe3O4SiO2-GSH MNPs) based on iron oxide magnetic nanoparticles (Fe3O4 MNPs), coated with SiO2 shells and further modified via reduced glutathione (GSH), was successfully synthesized and applied for Pb(II) removal. Characterization results suggested that the prepared nanoadsorbents were in uniform size and provided numerous adsorption sites for Pb(II), nanoparticles could be convenient separated with the help of external magnet due to their superparamagnetism. Adsorption results showed that the prepared nanoadsorbents exhibited excellent adsorption capacity, even at a large range of Pb(II) concentrations and ionic strength scope. Kinetic of the Pb(II) adsorption was found to follow pseudo-second-order rate equation. Adsorption isotherm data was best fitted to Freundlich model (R2 = 0.9888–0.9959), and the maximal Pb(II) adsorption capacities were calculated as 298.87, 332.44 and 357.37 mg g−1, at 298, 303 and 308 K, respectively. Based on the efficient Pb(II) adsorption ability and reusability studies, Fe3O4SiO2-GSH MNPs were confirmed to be a promising candidate for Pb(II) removal from industrial effluents.

Feasibility of bioleaching combining with Fenton-like reaction to remove heavy metals from sewage sludge was investigated. After 5-day bioleaching, the sludge pH decreased from 6.95 to 2.50, which satisfied the acidic conditions for Fenton-like reaction. Meanwhile, more than 50% of sludge-borne heavy metals were dissolved except for Pb. The bioleached sludge was further oxidized with Fenton-like reaction, with an optimal H2O2 dosage of 5 g/L, the Cu, Zn, Pb and Cd removal reached up to 75.3%, 72.6%, 34.5% and 65.4%, respectively, and the residual content of heavy metals in treated sludge meets the requirement of Disposal of Sludge from Municipal Wastewater Treatment Plant – Control Standards for Agricultural Use (CJ/T 309-2009) of China for A grade sludge. Bioleaching combined with Fenton-like reaction was the most effective method for heavy metal removal, compared with 15-day bioleaching and inorganic acid leaching with 10% H2SO4, 10% HCl and 10% HNO3.

Groundwater quality deterioration has attracted world-wide concerns due to its importance for human water supply. Although more and more studies have shown that human activities and climate are changing the groundwater status, an investigation on how different groundwater heavy metals respond to human activity modes (e.g. mining, waste disposal, agriculture, sewage effluent and complex activity) in a varying climate has been lacking. Here, for each of six heavy metals (i.e. Fe, Zn, Mn, Pb, Cd and Cu) in groundwater, we use >330 data points together with mixed-effect models to indicate that (i) human activity modes significantly influence the Cu and Mn but not Zn, Fe, Pb and Cd levels, and (ii) annual mean temperature (AMT) only significantly influences Cu and Pb levels, while annual precipitation (AP) only significantly affects Fe, Cu and Mn levels. Given these differences, we suggest that the impacts of human activity modes and climate on heavy metal "spread" in groundwater are biased.

The distribution and potential ecological risks of eight heavy metal elements including Cr, Cu, Zn, As, Cd, Pb, Hg, and W in the overlying water and sediments of the Taojiang River were investigated. The concentrations of eight heavy metals were measured by inductively coupled plasma mass spectrometer (ICP-MS), and the distribution coefficients were exploited to estimate the partition coefficient between overlying water and sediment phases, which were subsequently used to establish the potential ecological risk of heavy metals in sediments. The results revealed that the contents of Pb (33.47 μg·L−1), Cd (153.03 μg·L−1) and Hg (1.12 μg·L−1) in the water samples exceeded threshold values as proposed by the limits of the class III environmental quality standard. On the other hand, Cr, Cu, Zn, As, and Pb within sediments were below threshold limits.

The development of carbon materials brings a new two-dimensional catalyst support, graphdiyne (GDY), which is attracting increasing interest in the field of catalysis. This article presents a systematical review of recent studies about the characteristics, design strategies, and applications of GDY-supported catalysts. The sp- and sp2-hybridized carbon, high electrical conductivity, direct band gap, and high intrinsic carrier mobility are key characteristics for GDY to serve as a competitive catalyst support. Hydrothermal method (or solvothermal method), GDY in-situ growth, and electrochemical deposition are commonly used to load catalysts on GDY support. In the applications of GDY-supported photocatalysts, GDY mainly serves as an electron or hole transfer material. For the electrocatalytic hydrogen production, the unique electronic structure and high electrical conductivity of GDY can promote the electron transfer and water splitting kinetics. This review is expected to provide meaningful insight and guidance for the design of GDY-supported catalysts and their applications.

Both green tea (GT) extract and vitamin C (VC) were used for the reduction of Fe3+ to Fe0 using a green synthesis method. Modified nanozero-valent iron ([email protected] nanocomposites) was successfully obtained and characterized as α-Fe0-iron oxide/VC by multiple analytical methods. The [email protected] nanocomposites showed better transportability than nZVI, in that transport behavior was slightly dependent on various ratios of sand/soil in water-saturated heterogeneous porous media. Breakthrough curves of [email protected] nanocomposites in paddy soil exhibited “blocking effects” and were well described using a first-order straining coefficient (k2) on site 2 obtained from a two-site kinetic attachment model. In particular, [email protected] (VC/Fe = 0.6) showed higher Cr(VI) removal (especially reducibility) in both paddy soil and water compared to that of nZVI and VC. It is likely that the synergistic effects of VC (ascorbic acid) and tea polyphenols can increase the released free electrons into solution, favoring the high reduction of Cr(VI) into Cr(III) (i.e., FeOCr2O3, Cr(OH)3 and Cr2O3), where Cr(III) is prone to be immobilized by the nanocomposites in soil. This research highlights that VC can mediate the activation of GT extract to successfully modify nZVI, which could be beneficial for efficient transport in subsurface and remediation of Cr(VI)-contaminated soil and underground water.

The prevalence of organic micropollutants (OMPs) and their persistence in water supplies have raised serious concerns for drinking water safety and public health. Conventional water treatment technologies, including adsorption and biological treatment, are known to be insufficient in treating OMPs and have demonstrated poor selectivity toward a wide range of OMPs. Pressure-driven membrane filtration has the potential to remove many OMPs detected in water with high selectivity as a membrane's molecular weight cutoff (MWCO), surface charge, and hydrophilicity can be easily tailored to a targeted OMP's size, charge and octanol-water partition coefficient (Kow). Over the past 10 years, polymeric (nano)composite microfiltration (MF), ultrafiltration (UF), and nanofiltration (NF) membranes have been extensively synthesized and studied for their ability to remove OMPs. This review discusses the fate and transport of emerging OMPs in water, an assessment of conventional membrane-based technologies (NF, reverse osmosis (RO), forward osmosis (FO), membrane distillation (MD) and UF membrane-based hybrid processes) for their removal, and a comparison to the state-of-the-art nanoenabled membranes with enhanced selectivity toward specific OMPs in water. Nanoenabled membranes for OMP treatment are further discussed with respect to their permeabilities, enhanced properties, limitations, and future improvements.

Biological nitrogen fixation is highly controlled at the transcriptional level by regulatory networks that respond to the availability of fixed nitrogen. In many diazotrophs, addition of excess ammonium in the growth medium results in immediate repression of nif gene transcription. Although the regulatory cascades that control the transcription of the nif genes in proteobacteria have been well investigated, there are limited data on the kinetics of ammonium-dependent repression of nitrogen fixation.Here we report a global transcriptional profiling analysis of nitrogen fixation and ammonium repression in Pseudomonas stutzeri A1501, a root-associated and nitrogen-fixing bacterium. A total of 166 genes, including those coding for the global nitrogen regulation (Ntr) and Nif-specific regulatory proteins, were upregulated under nitrogen fixation conditions but rapidly downregulated as early as 10 min after ammonium shock. Among these nitrogen fixation-inducible genes, 95 have orthologs in each of Azoarcus sp. BH72 and Azotobacter vinelandii AvoP. In particular, a 49-kb expression island containing nif and other associated genes was markedly downregulated by ammonium shock. Further functional characterization of pnfA, a new NifA-sigma54-dependent gene chromosomally linked to nifHDK, is reported. This gene encodes a protein product with an amino acid sequence similar to that of five hypothetical proteins found only in diazotrophic strains. No noticeable differences in the transcription of nifHDK were detected between the wild type strain and pnfA mutant. However, the mutant strain exhibited a significant decrease in nitrogenase activity under microaerobic conditions and lost its ability to use nitrate as a terminal electron acceptor for the support of nitrogen fixation under anaerobic conditions.Based on our results, we conclude that transcriptional regulation of nif gene expression in A1501 is mediated by the nif-specific and ntr gene regulatory systems. Furthermore, microarray and mutational analyses revealed that many genes of unknown function may play some essential roles in controlling the expression or activity of nitrogenase. The findings presented here establish the foundation for further studies on the physiological function of nitrogen fixation-inducible genes.

Functionalization of carbon nanomaterials (including fullerenes, single-walled carbon nanotubes, multi-walled carbon nanotubes (MWCNTs), and graphene sheets) dispersed in water with macromolecules was achieved by a one-step strategy using β-cyclodextrin polymer (CDP). CDP-carbon nanomaterials were characterized by ultraviolet–visible, Raman, and Fourier transform infrared spectroscopies, transmission and scanning electron microscopies, and thermogravimetric analysis. These nanomaterials showed high solubility and stability in water because of the noncovalent interaction between carbon nanomaterials and CDP. The supramolecular recognition abilities of CDP-carbon nanomaterials were studied by cyclic voltammetry (CV). CDP-MWCNTs were also decorated by p-aminothiophenol (PATP) which formed inclusion complexes with the CDP. The conjugates (PATP-CDP-MWCNTs) were ideal templates for the highly efficient assembly of noble metal nanoparticles (Au and Pt) with dramatically different properties. Methanol oxidation of Pt-decorated PATP-CDP-MWCNTs in CV analyses indicated its potential application in direct methanol fuel cells, facilitating the feasibility of metal-decorated CDP-carbon nanomaterials in real technological applications. This universal method of producing carbon nanomaterials functionalized with macromolecules is beneficial for investigating the structure–performance relationship of carbon nanomaterials for designing compounds with specialized functions.

Unlike most Pseudomonas, the root-associated bacterium Pseudomonas stutzeri A1501 fixes nitrogen after the horizontal acquisition of a nitrogen-fixing (nif) island. A genome-wide search for small noncoding RNAs (ncRNAs) in P. stutzeri A1501 identified the novel P. stutzeri-specific ncRNA NfiS in the core genome, whose synthesis was significantly induced under nitrogen fixation or sorbitol stress conditions. The expression of NfiS was RNA chaperone Hfq-dependent and activated by the sigma factor RpoN/global nitrogen activator NtrC/nif-specific activator NifA regulatory cascade. The nfiS-deficient mutant displayed reduced nitrogenase activity, as well as increased sensitivity to multiple stresses, such as osmotic and oxidative stresses. Secondary structure prediction and complementation studies confirmed that a stem-loop structure was essential for NfiS to regulate the nitrogenase gene nifK mRNA synthesis and thus nitrogenase activity. Microscale thermophoresis and physiological analysis showed that NfiS directly pairs with nifK mRNA and ultimately enhances nitrogenase activity by increasing the translation efficiency and the half-life of nifK mRNA. Our data also suggest structural and functional divergence of NfiS evolution in diazotrophic and nondiazotrophic backgrounds. It is proposed that NfiS was recruited by nifK mRNA as a novel regulator to integrate the horizontally acquired nif island into host global networks.

Amorphous poly alpha olefin (APAO) was added into the waste tire rubber (WTR) modified asphalt and its effects on aging properties of WTR modified asphalt were investigated. Thin Film Oven Test (TFOT) and Pressure aging vessel (PAV) test were conducted to simulate the short-term and long-term aging respectively. Conventional properties including penetration, softening point, and viscosity were tested; Dynamic Shear Rheometer (DSR) test were conducted both to evaluate the properties of asphalt. The results showed that higher percentage retained penetration, lower softening point increment, and smaller viscosity aging index were gained after adding APAO to WTR modified asphalt. Closer G∗ and δ curves, smaller G∗ ratios due to the introduction of APAO confirmed the improved aging resistance. Higher G∗/sinδ at high temperature and smaller G∗·sinδ at intermediate temperature indicates WTR and APAO are beneficial to improving resistance to permanent deformation and fatigue cracking. Fourier Transform Infrared Spectroscopy (FTIR) measurements revealed that the double bonds in APAO and WTR were consumed for building a strengthened network in WTR modified asphalt and this may explain the better anti-aging properties of WTR + APAO compound modified asphalt.

In recent years, waste tire rubber (WTR) has been widely used as an asphalt modifier, due to its good interaction with asphalt particles. Another modifier, amorphous poly alpha olefin (APAO) also gains popular interest from researchers because of its excellent miscibility with rubber, asphalt, and its remarkable aging resistance. This study aims at investigating the compound modification effect of WTR/APAO on the properties of asphalt binders. Their rheological features were measured through conventional and dynamic shear tests; low temperature performance was investigated by bending beam rheometer test; mixture stability was measured by storage stability test. The result of decreased penetration, increased softening point, elastic recovery, viscosity and complex modulus indicates that WTR/APAO compound modification improves the high temperature performance and rutting resistance of asphalt binders. Moreover the binders with additional incorporation of APAO obviously performed better than those modified with WTR alone, especially in storage stability. However, the modification effect of WTR and APAO on low temperature rheological properties of asphalt is unclear and controversial, as both creep stiffness and m-value decreased in the BBR test.

Traditional three-domain fungal and bacterial laccases have been extensively studied for their significance in various biotechnological applications. Growing molecular evidence points to a wide occurrence of more recently recognized two-domain laccase-like multicopper oxidase (LMCO) genes in Streptomyces spp. However, the current knowledge about their ecological role and distribution in natural or artificial ecosystems is insufficient. The aim of this study was to investigate the diversity and composition of Streptomyces two-domain LMCO genes in agricultural waste composting, which will contribute to the understanding of the ecological function of Streptomyces two-domain LMCOs with potential extracellular activity and ligninolytic capacity. A new specific PCR primer pair was designed to target the two conserved copper binding regions of Streptomyces two-domain LMCO genes. The obtained sequences mainly clustered with Streptomyces coelicolor, Streptomyces violaceusniger, and Streptomyces griseus. Gene libraries retrieved from six composting samples revealed high diversity and a rapid succession of Streptomyces two-domain LMCO genes during composting. The obtained sequence types cluster in 8 distinct clades, most of which are homologous with Streptomyces two-domain LMCO genes, but the sequences of clades III and VIII do not match with any reference sequence of known streptomycetes. Both lignocellulose degradation rates and phenol oxidase activity at pH 8.0 in the composting process were found to be positively associated with the abundance of Streptomyces two-domain LMCO genes. These observations provide important clues that Streptomyces two-domain LMCOs are potentially involved in bacterial extracellular phenol oxidase activities and lignocellulose breakdown during agricultural waste composting.

Composting is identified as an effective approach for solid waste disposal. The bioremediation of 4-nonylphenol (4NP) and cadmium (Cd) co-contaminated sediment was investigated by composting with Phanerochaete chrysosporium (P. chrysosporium) inocula. P. chrysosporium inocula and proper C/N ratios (25.51) accelerated the composting process accompanied with faster total organic carbon loss, 4NP degradation and Cd passivation. Microbiological analysis demonstrated that elevated activities of lignocellulolytic enzymes and sediment enzymes was conducive to organic chemical transformation. Bacterial community diversity results illustrated that Firmicutes and Proteobacteria were predominant species during the whole composting process. Aerobic cellulolytic bacteria and organic degrading species played significant roles. Toxicity characteristic leaching procedure (TCLP) extraction and germination indices results indicated the efficient detoxification of 4NP and Cd co-contaminated sediment after 120 days of composting. Overall, results demonstrated that P. chrysosporium enhanced composting was available for the bioremediation of 4NP and Cd co-contaminated sediment.

Formic acid (FA) has come to be considered as a potential material for chemical storage of hydrogen. Despite tremendous efforts, the development of highly efficient and relatively low-cost heterogeneous catalysts for dehydrogenation of FA remains a major challenge; the weak recyclability of catalyst limits its application in industry. In this work, the synthesis of Pd nanoparticles immobilized on UIO-66 amino grafting sepiolite (SEP) dual supports is by an impregnation-reduction method. The UIO-66 framework on fibrous amine-functionalized SEP support can significantly prevent agglomeration during the dehydrogenation process and control the size of Pd nanoparticles. The sacrificial effect of Pd nanoparticles from UIO-66 enables the active sites on NH2-SEP to maintain consistent catalytic activity and reusability in additive-free FA solution over 8th recycled use. Compared to current catalyst systems, this catalyst offers a brighter prospect of novel and efficient heterogeneous catalysis for formic acid dehydrogenation.

The cost-effective and environmentally friendly substrates are vital for the design of constructed wetlands (CWs). This study explored the incorporation of basalt fiber (BF) into CWs as substrates for enhancing purification performance and comparative investigated the advantage of enzyme activities and microbial community of basalt fiber constructed wetland (BF-CW) compared with conventional constructed wetland (C-CW). It was found that the addition of BF obviously improved removal efficiencies of nitrogen and phosphorus around 10 ~ 25%, especially under high pollutant loading. Further substrate enzyme activity analysis showed that the dehydrogenase (DHA), urease (UA) and phosphatase (PST) activities of BF-CW were higher than those of C-CW. Moreover, high-throughput sequencing analysis revealed that the abundance of key functional bacteria was higher in BF-CW than C-CW, and the community structure in BF-CW was more resistant to changes in pollutant loadings. These results indicated that BF could be used as a new alternative substrate in CWs technology.

• The new magnetic nanocomposites (MNC@PmPD) was synthesized in situ polymerization. • The maximum adsorption capacity of MNC@PmPD 2 for Cr(VI) was 240.44 mg·g -1 . • The possible adsorption and reduction mechanism of Cr(VI) was proposed. A novel core–shell magnetic nanomaterial is synthesized to adsorb highly toxic chromium (Cr(VI)) from water. Cobalt-based MOF (ZIF-67) is used as precursor to prepare magnetic nanoporous carbon (MNC) by one-step carbonization and etching process. Poly(m-phenylenediamine) (PmPD) is assembled on the surface of MNC by in-situ polymerization at low temperature. The magnetic MNC@PmPDs with definite core-shell structure are successfully fabricated. The adsorption capacity of MNC@PmPD 2 for Cr(VI) can reach 240.44 mg·g - 1 , much higher than the bare MNC (126.27 mg·g - 1 ). The core–shell structure improves the adsorption efficiency of the PmPD shell to 445.64 mg·g - 1 , compared with that of bare PmPD (332 mg·g - 1 ). The MNC@PmPD 2 can be easily separated from the solution by the advantage of magnetic-core. Moreover, the prepared MNC@PmPD 2 exhibits high stability during adsorption with negligible Co leaching and structural decomposition. The mechanism of Cr(VI) removal is considered to be based on the synergistic effect of adsorption and reduction. The removal rate of Cr(VI) follows the pseudo-second-order model and the adsorption isotherm data fits well to the modified Langmuir isothermal model. The excellent adsorption capacity, easy magnetic separation and high structure stability indicate a promising application of MNC@PmPD for Cr(VI) remediation in wastewater.

Despite the importance of fixation in determining green tea quality, its role in reducing the bitter and astringent taste of this beverage remains largely unknown. Herein, an electromagnetic roller-hot-air-steam triple-coupled fixation (ERHSF) device was developed, and its operating parameters were optimized (steam volume: 20 kg/h; hot-air temperature: 90 °C; hot-air blower speed: 1200 r/min). Compared with conventional fixation treated samples, the ratio of tea polyphenols to free amino acids and ester-catechins to simple-catechins in ERHSF-treated samples was reduced by 11.0% and 3.2%, reducing bitterness and astringency of green tea; amino acids, soluble sugars, and chlorophyll contents were significantly increased, enhancing the freshness, sweetness, and greenness; the color indexes, such as L/L* value of brightness and -a/-a* value of greenness, were also improved, and ERHSF-treated samples had the highest sensory scores. These results provided theoretical support and technical guidance for precise quality improvement of summer-autumn green tea.

Drying temperature (DT) considerably affects the flavor of black tea (BT); however, its influence on non-volatile metabolites (NVMs) and their correlations remain unclear. In this study, an objective quantification technique and widely targeted metabolomics were applied to explore the effects of DT (130 °C, 110 °C, 90 °C, and 70 °C) on BT flavor and NVMs conversion. BT with a DT of 90 °C presented the highest umami, sweetness, overall taste, and brightness color values. Using the weighted gene co-expression network and multiple factor analysis, 455 sensory trait-related NVMs were explored across six key modules. Moreover, 169 differential NVMs were screened, and flavonoids, phenolic acids, amino acids, organic acids, and lipids were identified as key differential NVMs affecting the taste and color attributes of BT in response to DT. These findings enrich the BT processing theory and offer technical support for the precise and targeted processing of high-quality BT.

The effects of rhamnolipids and Triton X-100 on phenol adsorption by Penicillium simplicissimum were studied. The optimum pH was 7 for phenol adsorption by all the test biomasses. The adsorption of phenol at pH 7 by biomass pre-treated with 0.05% Triton X-100, 0.2% Triton X-100, 0.05% rhamnolipids and 0.005% rhamnolipids was 3.4, 2.7, 2.4, and 1.8-fold, respectively, that of untreated biomass. The pseudo-second-order model and the Freundlich isotherms described the adsorption processes better than the pseudo-first-order model and the Langmuir isotherms, respectively. The pre-treatments by surfactants increased the zeta potential and hydrophobicity of P. simplicissimum. Analysis of the cell surface by Fourier transform infrared spectrometry, energy dispersive X-ray, and environmental scanning electron microscopy indicated that the pre-treatments by surfactants changed the cell surface functional groups, element concentrations and micrographs. The results indicated that surfactants can be potentially used to increase phenol adsorption.

Abstract In this study, the effects of carbon additions on the microstructure, hardness, transverse rupture strength and abrasion resistance of Ti(C,N)-Fe cermets manufactured by powder metallurgy method were investigated by scanning electron microscopy, X-ray diffraction and mechanical properties tests. The results show that the microstructure of sintered Ti(C,N)-Fe cermets exhibits the homogeneous distribution of Ti(C,N) hard phase when 1.0 wt% carbon was added into the cermets. The transverse rupture strength of cermet can reach the peak of 2435 MPa and the fracture morphology can include a vast of transgranular fracture. Moreover, the comprehensive performance of Ti(C,N)-Fe cermets can improve significantly through the heat-treatment process. The hardness and transverse rupture strength of cermets after heat-treatment are 70.0HRC and 2483.2 MPa. The Ti(C,N)-Fe cermets have a potential application in machining.

With increasing arsenic (As) contamination incidents reported around the world, better processes for As removal from industrial wastewater and other contaminated waters are required to protect drinking water sources. Complexation of As with cetylpyridinium chloride (CPC) cationic surfactant micelles, coupled with ultrafiltration (UF), has the potential to improve As removal, but competition from other anions could be a limiting factor. Using a binary-system ion-exchange model, the selectivity coefficients for binding of the monovalent and divalent forms of arsenate (As (V)) to cationic cetylpyridinium (CP+) micelles, relative to Cl-, were determined to be 0.55 for H2AsO4- and 0.047 mol L-1 for HAsO42-, respectively. The affinity sequence for binding of commonly occurring monovalent anions by CP+ micelles was found to be NO3- > Cl- > HCO3- > H2AsO4-, and for divalent anions, SO42- > HAsO42-. Distribution of As (V) between the micellar and aqueous phases was explored using ion exchange isotherms, with higher pH and lower concentrations of competing anions increasing rejection of As (V) across UF membranes. A model accounting for these effects, based on mass balances across UF membranes and selectivity coefficients for binding of anions to the CP+ micelles, was used to predict As (V) removal during micellar-enhanced ultrafiltration (MEUF) of mixtures of competing anions. Model predictions agreed well with experiment results for both artificial and spiked natural river water samples. Arsenic (≈0.1 mM) removals of 91% and 84% were achieved from artificial waters and spiked natural river waters, respectively, by adding 20 mM CPC prior to UF.

A Mg₉₂V₈@C nanocomposite with over 94% loading shows high capacity and superb kinetics from the synergetic effects of nanoconfinement and the V catalyst.

Nematophagous fungi employ three distinct predatory strategies: nematode trapping, parasitism of females and eggs, and endoparasitism. While endoparasites play key roles in controlling nematode populations in nature, their application for integrated pest management is hindered by the limited understanding of their biology. We present a comparative analysis of a high quality finished genome assembly of Drechmeria coniospora, a model endoparasitic nematophagous fungus, integrated with a transcriptomic study. Adaptation of D. coniospora to its almost completely obligate endoparasitic lifestyle led to the simplification of many orthologous gene families involved in the saprophytic trophic mode, while maintaining orthologs of most known fungal pathogen-host interaction proteins, stress response circuits and putative effectors of the small secreted protein type. The need to adhere to and penetrate the host cuticle led to a selective radiation of surface proteins and hydrolytic enzymes. Although the endoparasite has a simplified secondary metabolome, it produces a novel peptaibiotic family that shows antibacterial, antifungal and nematicidal activities. Our analyses emphasize the basic malleability of the D. coniospora genome: loss of genes advantageous for the saprophytic lifestyle; modulation of elements that its cohort species utilize for entomopathogenesis; and expansion of protein families necessary for the nematode endoparasitic lifestyle.

O-Methylation modulates the pharmacokinetic and pharmacodynamic (PK/PD) properties of small-molecule natural products, affecting their bioavailability, stability, and binding to targets. Diversity-oriented combinatorial biosynthesis of new chemical entities for drug discovery and optimization of known bioactive scaffolds during drug development both demand efficient O-methyltransferase (OMT) biocatalysts with considerable substrate promiscuity and tunable regioselectivity that can be deployed in a scalable and sustainable manner. Here we demonstrate efficient total biosynthetic and biocatalytic platforms that use a pair of fungal OMTs with orthogonal regiospecificity to produce unnatural O-methylated benzenediol lactone polyketides. We show that rational, structure-guided active-site cavity engineering can reprogram the regioselectivity of these enzymes. We also characterize the interplay of engineered regioselectivity with substrate plasticity. These findings will guide combinatorial biosynthetic tailoring of unnatural products toward the generation of diverse chemical matter for drug discovery and the PK/PD optimization of bioactive scaffolds for drug development.

The application of polymer–surfactant aggregates (PSAs) to recover heavy metal ions from water is a novel treatment process for aqueous metallic effluents. To better employ this strategy, branched polyethylenimine (PEI), sodium dodecyl sulfate (SDS) and copper ions were selected to investigate their interaction in water and to improve the recyclable PSAs process for metal removal and recovery. Electrostatic association between PEI and SDS caused the formation of PSAs, and the addition of SDS to a partially protonated PEI solution caused a pH increase; however, re-dispersal of PSAs could be achieved via an increase in pH. Precipitation of PSAs depended on pH, SDS/PEI concentration ratio and the total concentration of PEI; the optimal SDS/PEI ratio decreased as pH increased, and a higher concentration of PEI showed a greater potential to precipitate. PEI formed a strong complex with Cu2+, with the most stable complex at a PEI/Cu chelation ratio of 4. Acidification decreased the chelation capacity of PEI to Cu2+, because of the competition from protons for amino groups. Complexation with Cu2+ in turn reduced the proton buffer capacity of PEI in a non-acid solution. The removal of Cu2+ increased by increasing the total PEI concentration, or by increasing pH from 1 to above 4. Ionic strength and hardness had no marked effect on Cu2+ removal using the PSAs process. Following the initial interaction among PEI, SDS and Cu2+, the Cu2+ could then be released from the PSAs by acidification and the reuse of the PSAs material could be achieved by alkalization. Copper removal and recovery were still up to 98 % and 88 % after three reuse cycles of the PSAs process, respectively.

Ecosystem services provide important support for the sustainable development of humans; these services are provided by various ecosystems, but they have been severely influenced by anthropogenic activities globally in the past several decades. To respond to the Sustainable Development Goals of the United Nations, this study investigated the changes in ecosystem structure and estimated the associated ecosystem services value (ESV) since China’s reform and opening-up policy in the Guangdong-Hong Kong-Macao Greater Bay Area (GBA), one of the most developed and populous areas of China. Our results showed that dramatic changes in ecosystem structure occurred in the GBA, characterized by unpresented construction land sprawl (an average of 148 km2/yr) and extensive farmland loss (an average of 111 km2/yr). The change size and rate of ecosystems from 2000 to 2010 was the biggest and fastest, followed by that from 1990 to 2000. The ESV of the study area showed an overall decreasing trend, declining from 464 billion yuan to 346 billion yuan. The ESV supported by forest ecosystems and water body ecosystems made dominant contributions to the total ESV, ranging from 92% to 95%. Strong spatial heterogeneity of the ESV of the GBA might be noted throughout the study period, with lower values in the central region and higher values in the surrounding region. To realize sustainable development in the GBA; this study strongly suggests that local governments, and the public, scientifically use various ecosystems and their services, focusing on vigorously protecting ecosystems with high and important ESVs, such as water body, wetland, forest, and farmland ecosystems.

For organic film capacitors, the dielectric materials with high-k, flexible and high heat-resistance are desired. Herein, a kind of hybrid particles were fabricated via self-polymerization and crosslinking reaction, containing core-shell structured BaTiO3@polydopamine ([email protected]) and MoS2@polydopamine (MoS2@PDA) interlinked with poly(ethylene imine) (PEI) to perserve better interfacial interaction and uniform dispersion in poly(arylene ether nitrile) (PEN) composites. The results suggest that the designed PEN-based composites demonstrate remarkable dielectric responses. The incorporation of hybrid particles endows the polymer composites with high relative dielectric constant and comparable low dielectric loss due to the construction of diffuse electrical double layer and more micro-capacitor networks in PEN-based composites. Particularly, the dielectric constant of composite loaded with 15 wt% hybrid particles is about 254% higher than that of PEN matrix at 1 kHz, while maintaining a relatively low dielectric loss (＜0.03). More importantly, the PEN-based composites maintain their dielectric constants from room temperature to 160 °C, thus exhibiting outstanding permittivity-temperature stability, which can better meet the requirements of high temperature applications. In conclusion, this is a feasible way to incorporate hybrid particles containing core-shell structured [email protected] and MoS2@PDA into polymer matrix to design dielectric composites with excellent permittivity-temperature stability.

Abstract New materials for electrochemical energy storage and conversion are the key to the electrification and sustainable development of our modern societies. Molecular modelling based on the principles of quantum mechanics and statistical mechanics as well as empowered by machine learning techniques can help us to understand, control and design electrochemical energy materials at atomistic precision. Therefore, this roadmap, which is a collection of authoritative opinions, serves as a gateway for both the experts and the beginners to have a quick overview of the current status and corresponding challenges in molecular modelling of electrochemical energy materials for batteries, supercapacitors, CO 2 reduction reaction, and fuel cell applications.

Delftia tsuruhatensis AD9 was isolated as an aniline-degrading bacterium from the soil surrounding a textile dyeing plant. The gene cluster involved in aniline degradation was cloned from the total DNA of strain AD9 into Escherichia coli JM109. After shotgun cloning, two recombinant E. coli strains showing aniline oxidation activity or catechol meta -cleavage activity were obtained by simple plate assays. These strains contained 9·3 kb and 15·4 kb DNA fragments, respectively. Sequence analysis of the total 24·7 kb region revealed that this region contains a gene cluster (consisting of at least 17 genes, named tadQTA1A2BRD1C1D2C2EFGIJKL ) responsible for the complete metabolism of aniline to TCA-cycle intermediates. In the gene cluster, the first five genes ( tadQTA1A2B ) and the subsequent gene ( tadR ) were predicted to encode a multi-component aniline dioxygenase and a LysR-type regulator, respectively, while the others ( tadD1C1D2C2EFGIJKL ) were expected to encode meta -cleavage pathway enzymes for catechol degradation. In addition, it was found that the gene cluster is surrounded by two IS 1071 sequences, indicating that it has a class I transposon-like structure. PFGE and Southern hybridization analyses confirmed that the tad gene cluster is encoded on the chromosome of strain AD9 in a single copy. These results suggest that, in strain AD9, aniline is degraded via catechol through a meta -cleavage pathway by the chromosome-encoded tad gene cluster. The tad gene cluster showed significant similarity in nucleotide sequence and genetic organization to the plasmid-encoded aniline degradation gene cluster of Pseudomonas putida UCC22.

A concept of delayed geochemical hazard (DGH) was proposed instead of chemical time bomb to represent an ecological and environmental hazard caused by sudden reactivation and release of long-term accumulated pollutants in soil/sediment system due to the change of physicochemical conditions or the decrease of environmental capacity. A DGH model was also established to provide a quantitative tool to assess and predict potential environmental risk caused by heavy metals and especially its dynamic evolutions. A case study of DGH was carried out for a mercury-polluted area in southern China. Results of soil column experiment showed that DGH was directly resulted from the transformation and release of pollutant from the releasable species to the active ones through a mechanism of chain reaction. The most possible chain reaction was summarized as HgE+C+F+O+R → HgE+C+F+O → HgE+C+F → HgE+C → HgE. Although 8.3% of the studied area with the total releasable content of mercury (TRCPHg) exceeded the DGH critical point value of 16.667 mg/kg, with the possibility of DGH burst, the area was classified as low-risk of DGH. This confirmed that DGH model could contribute to the risk assessment and early warning of soil/sediment pollution.

A higher efficiency of excitation energy transfer occurs to a luminescent diphenylanthracenyl acceptor incorporated at the centre, rather than the end, of an acenaphthylene polymer chain.

Maleic anhydride (MAH) functionalized acrylate-styrene-acrylonitrile (ASA) copolymers (F-ASA) were prepared via an emulsion polymerization process. The F-ASA particles were used to toughen Polyamide-6 (PA-6). Molau tests showed the compatibilization reactions between PA-6 and F-ASA. The notched impact strength of PA-6 was effectively improved by the use of F-ASA. At a rubber content of 20% by weight in PA-6/F-ASA blends, it was found that the impact strength increased with the MAH content. When the MAH content was 8% in F-ASA, the impact strength was 1008 J/m. The influence of rubber content on the properties of PA-6/F-ASA8 blends was investigated. The results showed that brittle-ductile transition took place when the rubber content was 20%. Moreover, increasing the MAH content of the blends reduced the brittle-ductile temperature of the F-ASA/PA-6 blends from 50 °C to about 0 °C. Scanning electron microscopy (SEM) results showed that cavitation of rubber particles and shear yielding of the PA-6 matrix were the major toughening mechanisms.

Two disparate polyketide families, the benzenediol lactones and the azaphilones, are produced by fungi using iterative polyketide synthase (iPKS) enzymes consisting of collaborating partner subunits. Exploitation of this common biosynthetic logic using iPKS subunit shuffling allowed the diversity-oriented combinatorial biosynthesis of unprecedented polyketide scaffolds new to nature, bearing structural motifs from both of these orthogonal natural product families. Starter unit acyltransferase domain replacements proved necessary but not sufficient to guarantee communication between iPKS subunits.

The objective of this study is to examine the aging characteristics of amorphous poly alpha olefin (APAO) modified asphalt binders. The anti-aging performance of APAO modified asphalt binders were investigated through a comprehensive laboratory program. The content of APAO was 2%, 4%, 6% and 8% of the mass of the asphalt binders. The asphalt binders underwent the rolling thin film oven (RTFO) test and pressure aging vessel (PAV) test. The aging characteristics of asphalt binders were evaluated with rotational viscometer (RV), dynamic shear rheometer (DSR) and bending beam rheometer (BBR). The morphological properties of asphalt binders were investigated with the Fourier transform infrared spectrum (FTIR) tests. The conventional performance of asphalt binder was improved after mixed with APAO. The optimum APAO content was 6% by mass of asphalt binders for proposed 70# asphalt according to comprehensive test of APAO modified asphalt binders (AMB). The high temperature performance grade of AMB was increased without sacrificing the low temperature performance grade, and the temperature susceptibility was increased under different aging conditions. The aging performance of AMB was verified to be better than base asphalt binders. The rutting resistance of AMB was improved significantly even after short- and long-term aging. The base asphalt binders and APAO went through physical mixing and chemical reaction in the process of mixing. The carbonyl and sulphoxide index verified the higher anti-aging performance of AMB on a morphological scale.

Divalent cations such as Ba2+, Sr2+, Ca2+, and Mg2+, commonly found in oil/gas produced water at high concentrations, adversely affect oil and gas production by forming scales in pipes, tanks, process equipment such as oil-water separators, and treatment equipment such as filters and reverse osmosis membranes. If the water is reinjected, e.g., for water flooding, scales may also form on the well screens and in the producing formation. Water soluble polyelectrolytes have been used to inhibit scale formation in oil and gas production and to eliminate cationic metals from water via membrane separation. However, the underlying interactions between scale-forming cations and various polyelectrolytes are not well understood. To this end, two commercially available anionic polyelectrolytes with different repeating functional groups, poly(acrylic acid) (PAA) and poly(sodium 4-styrenesulfonate) (PSS), were used to evaluate complexation and precipitation of Ba2+, Sr2+, Ca2+, and Mg2+ in binary systems, multi-ion mixtures, and produced water. The apparent dissociation constant (pKa) of PAA was determined by titration to be 6.7, indicating a high affinity of PAA for H+. The strength of the complexes formed between PAA and scale-forming cations (binding strength) decreased in the order Ba2+ > Ca2+ > Sr2+ > Mg2+ at pH 5. Higher pH values led to a higher affinity of PAA for divalent cations, which is attributable to the increase in binding sites for cations as the PAA more completely ionizes. By contrast, the affinity of PSS decreases in the order Ba2+ > Sr2+ > Ca2+ > Mg2+, with no significant pH effect. The formation and precipitation behavior of polyelectrolyte complexes (PECs) was investigated by reacting cations with the sodium salt of PAA (sodium polyacrylate) or with PSS. Only Ba2+ formed precipitates with PSS in single-cation solutions, although small amounts of Sr2+ were also removed by PSS from a mixed cation solution. However, all of the scale-forming cations formed PEC precipitates with PAA in both binary and mixed-ion solutions, depending on the cation concentration and molar ratio of PAA to divalent cations. The maximum amount of precipitation occurred at a molar ratio of PAA to M2+ of 1.5–1.7, while overdosing of PAA caused dispersion of the precipitates. High concentrations of monovalent cations inhibited precipitation of divalent cations with PAA. Up to 73% of scale-forming cations were removed from field-collected produced water samples through repeated (4 times) addition of PAA at a molar concentration ratio of 1. The release of scale-forming cations from PAA-M2+ precipitates, thereby regenerating PAA, was achieved by adding HCl.

To enhance the adsorption performance of natural calcium-based montmorillonite (Ca-MMT), the polymeric hydroxyaluminum cation - Keggin-Al30 ([Al30O8(OH)56(H2O)24]18+) and cetylpyridinium chloride (CPC) were used to modify Ca-MMT for preparation of CPC-Al30 pillared montmorillonite composite (CPC-Al30PMT). The CPC-Al30PMT was characterized via analysis of its chemical and physical structure, morphology, surface properties, and zeta potential. The results showed that the Al30 polymer cation and CPC successfully intercalated into the interlayer of Ca-MMT, which increased the d001 value from 1.47 nm to 1.93 nm, and increased the pore volume correspondingly. The zeta potential was reversed from negative to positive after modification, presenting a possibility to adsorb anionic contaminants from water. The investigation of hexavalent chromium (Cr (VI)) adsorption on CPC-Al30PMT showed that the removal of Cr (VI) was positively correlated with the dosage of adsorbent, and negatively correlated with the initial concentration of Cr (VI), the ionic strength and the initial pH of the solution. CPC-Al30PMT showed good Cr (VI) removal performance, with the maximum adsorption (qe) of 42.44 mg/g. The adsorption process conformed to Freundlich model and pseudo-second-order kinetic model. Thermodynamics studies showed that adsorption was a spontaneous exothermic process. Electrostatic interaction, ion exchange and reduction were the main mechanisms of the removal.

Shaking is an innovative technology employed in black tea processing to enhance flavor. However, the effects of shaking on the evolutionary mechanisms of volatile metabolites (VMs) remain unclear. In this study, we compared the effects of a shaking–withering method with those of traditional withering on the flavor and VMs transformation of black tea. The results showed that black tea treated with shaking exhibited excellent quality with floral and fruity aroma. Based on gas chromatography-tandem mass spectrometry, 128 VMs (eight categories) were detected. Combining variable importance projection with odor activity value analysis, eight key differential VMs were identified. Shaking could promote the oxidative degradation of fatty acids and carotenoids and modulate the biosynthesis of terpenoids to facilitate the formation of floral/fruity VMs (such as (Z)-hexanoic acid-3-hexenyl ester, ethyl hexanoate, trans-β-ionone, and decanal). Our findings provide theoretical guidance for the production of high-quality black tea with floral and fruity aromas.

Strain GIMN 1.002(T), a UV radiation-tolerant bacterium, was isolated from the upper sand layers of the Gobi desert, Xinjiang, China and characterized in order to determine its taxonomic position. Cells were Gram-reaction-positive, heterotrophic, strictly aerobic, short rods. 16S rRNA gene sequence analysis revealed that strain GIMN 1.002(T) belonged to the genus Microbacterium and was closely related to Microbacterium arborescens DSM 20754(T) (98.8 % 16S rRNA gene sequence similarity) and Microbacterium imperiale DSM 20530(T) (98.7 %). However, strain GIMN 1.002(T) had low DNA-DNA relatedness with M. arborescens DSM 20754(T) (17.1 %) and M. imperiale DSM 20530(T) (12.89 %). Strain GIMN 1.002(T) possessed chemotaxonomic markers that were consistent with its classification in the genus Microbacterium, i.e. MK-11, MK-12 and MK-10 as major menaquinones and anteiso-C(15 : 0) (38.67 %), iso-C(16 : 0) (18.16 %) and iso-C(15 : 0) (17.46 %) as predominant cellular fatty acids. The DNA G+C content was 67.74 mol%. The cell-wall sugar was rhamnose. On the basis of the data from this study, strain GIMN 1.002(T) represents a novel species of the genus Microbacterium, for which the name Microbacterium radiodurans sp. nov. is proposed. The type strain is GIMN 1.002(T) (=CCTCC M208212(T) =NRRL B-24799(T)).

ADVERTISEMENT RETURN TO BOOKPREVChapterNEXTBlock Copolymer Synthesis through the Use of Switchable RAFT AgentsGraeme Moad*Graeme Moad CSIRO Materials Science and Engineering, Bag 10, Clayton South, Victoria 3169, Australia ISOF-CNR, Area della Ricerca, Via P. Gobetti 101, 40129 Bologna, Italy*[email protected]More by Graeme Moad, Massimo BenagliaMassimo Benaglia CSIRO Materials Science and Engineering, Bag 10, Clayton South, Victoria 3169, Australia ISOF-CNR, Area della Ricerca, Via P. Gobetti 101, 40129 Bologna, ItalyMore by Massimo Benaglia, Ming ChenMing Chen CSIRO Materials Science and Engineering, Bag 10, Clayton South, Victoria 3169, Australia ISOF-CNR, Area della Ricerca, Via P. Gobetti 101, 40129 Bologna, ItalyMore by Ming Chen, John ChiefariJohn Chiefari CSIRO Materials Science and Engineering, Bag 10, Clayton South, Victoria 3169, Australia ISOF-CNR, Area della Ricerca, Via P. Gobetti 101, 40129 Bologna, ItalyMore by John Chiefari, Yen K. ChongYen K. Chong CSIRO Materials Science and Engineering, Bag 10, Clayton South, Victoria 3169, Australia ISOF-CNR, Area della Ricerca, Via P. Gobetti 101, 40129 Bologna, ItalyMore by Yen K. Chong, Daniel J. KeddieDaniel J. Keddie CSIRO Materials Science and Engineering, Bag 10, Clayton South, Victoria 3169, Australia ISOF-CNR, Area della Ricerca, Via P. Gobetti 101, 40129 Bologna, ItalyMore by Daniel J. Keddie, Ezio RizzardoEzio Rizzardo CSIRO Materials Science and Engineering, Bag 10, Clayton South, Victoria 3169, Australia ISOF-CNR, Area della Ricerca, Via P. Gobetti 101, 40129 Bologna, ItalyMore by Ezio Rizzardo, and San H. ThangSan H. Thang CSIRO Materials Science and Engineering, Bag 10, Clayton South, Victoria 3169, Australia ISOF-CNR, Area della Ricerca, Via P. Gobetti 101, 40129 Bologna, ItalyMore by San H. ThangDOI: 10.1021/bk-2011-1066.ch007Publication Date (Web):June 20, 2011Publication History Published online20 June 2011Published inprint 1 January 2011RIGHTS & PERMISSIONSNon-Conventional Functional Block CopolymersChapter 7pp 81-102ACS Symposium SeriesVol. 1066ISBN13: 9780841226142eISBN: 9780841226159 Copyright © 2011 American Chemical SocietyChapter Views333Citations9LEARN ABOUT THESE METRICSChapter Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit Read OnlinePDF (748 KB) SUBJECTS:Alkyls,Aromatic compounds,Hydrocarbons,Organic compounds,RAFT polymerization Get e-Alerts

A novel, Gram-stain-negative, non-motile, non-spore-forming, short rod-shaped, aerobic bacterium designated H-12(T) was isolated from a mixed sandy soil sample collected from Xinjiang, China. Strain H-12(T) grew at 20-37 °C (optimum, 30 °C), pH 7.0-11.0 (optimum, pH 8.5) on TGY medium with 0-5 % NaCl (w/v). 16S rRNA gene sequence analysis indicated that strain H-12(T) shared sequence similarities with Sphingobacterium composti DSM 18850(T) (90.0 %). Strain H-12(T) showed a low level of DNA-DNA relatedness to Sphingobacterium composti DSM 18850(T) (45.5 %). The predominant isoprenoid quinone of strain H-12(T) was MK-7 and the major polar lipid was phosphatidylethanolamine. The predominant cellular fatty acids were C16:1ω7c and/or C16 : 1ω6c, iso-C15 : 0, iso-C17 : 0 3-OH, C16 : 0, C16 : 0 3-OH and iso-C15 : 0 3-OH. DNA G+C content of strain H-12(T) was 44.15 mol%. On the basis of phenotypic, genetic and phylogenetic data, strain H-12(T) is proposed to be a representative of a novel species of the genus Sphingobacterium, for which the name Sphingobacterium arenae sp. nov. is suggested and the type strain is H-12(T) ( = ACCC 05758(T) = KCTC 32294(T)).

Surfactant micelles combined with ultrafiltration can partially, or sometimes nearly completely, separate various ionic and nonionic pollutants from water. To this end, the selectivity of aqueous micelles composed of either cetyltrimethylammonium (CTA+) bromide or cetylpyridinium (CP+) chloride toward many environmentally relevant anions (IO3-, F-, Cl-, HCO3-, NO2-, Br-, NO3-, H2PO4-, HPO42-, SO42-, and CrO42-) was investigated. Selectivity coefficients of CTA+ micelles (with respect to Br-) and CP+ micelle (with respect to Cl-) for these anions were evaluated using a simple thermodynamic ion exchange model. The sequence of anion affinity for the CTA+ micelles and for the CP+ micelles were the same, with decreasing affinity occurring in the order of: CrO42- > SO42- > HPO42- > NO3- > Br- > NO2- > Cl- > HCO3- > H2PO4- ≈ F-. From the associated component mass balance and ion exchange (i.e., mass action) equations, an overall speciation model was developed to predict the distribution of all anions between the aqueous and micellar pseudophase for complex ionic mixtures. Experimental results of both artificial and real surface waters were in good agreement to model predictions. Further, the results indicated that micelles combined with ultrafiltration may be a potential technology for nutrient and other pollutant removal from natural or effluent waters.

Summary Late embryogenesis abundant ( LEA ) proteins play a protective role during desiccation and oxidation stresses. LEA 3 proteins are a major group characterized by a hydrophilic domain ( HD ) with a highly conserved repeating 11‐amino acid motif. We compared four different HD orthologs from distant organisms: (i) Dr HD from the extremophilic bacterium Deinococcus radiodurans ; (ii) Ce HD from the nematode Caenorhabditis elegans ; (iii) Yl HD from the yeast Yarrowia lipolytica ; and (iv) Bn HD from the plant Brassica napus . Circular dichroism spectroscopy showed that all four HD s were intrinsically disordered in phosphate buffer and then folded into α‐helical structures with the addition of glycerol or trifluoroethanol. Heterologous HD expression conferred enhanced desiccation and oxidation tolerance to Escherichia coli . These four HD s protected the enzymatic activities of lactate dehydrogenase ( LDH ) by preventing its aggregation under desiccation stress. The HD s also interacted with LDH , which was intensified by the addition of hydrogen peroxide (H 2 O 2 ), suggesting a protective role in a chaperone‐like manner. Based on these results, the HD s of LEA 3 proteins show promise as protectants for desiccation and oxidation stresses, especially Dr HD , which is a potential ideal stress‐response element that can be applied in synthetic biology due to its extraordinary protection and stress resistance ability.

Deinococcus radiodurans adapts to challenging environments by modulating gene expression in response to oxidative stress. Recently, bacterial small noncoding RNAs (sRNAs) have been presumed to participate in the transcriptional or translational regulation of stress-responsive genes. We found 24 sRNAs that may be involved in the oxidative stress response of D. radiodurans by deep RNA sequencing. Moreover, a typical stress-inducible sRNA, IGR_3053, named OsiA, was predicted to bind to the mRNA of katA, katE, and sodC by the bioinformatics method. An osiA knockout of D. radiodurans displayed increased sensitivity to H2O2 and the decreased catalase activity and total antioxidant activity, suggesting that OsiA probably serves as a regulator in the adaptation to oxidative environments. Further microscale thermophoresis results demonstrated that OsiA can directly bind to the mRNA of katA, sodC, and katE. The stability test result of katA mRNA showed that its half-life was 2 min in the osiA mutant compared with 5 min in the wildtype(wt) strain. Our results indicated that OsiA can enhance the stability of katA mRNA and the activity of KatA and consequently the oxidation resistance of D.radiodurans. We are the first one to explore the super-strong oxidative stress resistance of D.radiodurans at the level of post-transcriptional regulation, and found a new pathway that provides a new explanation for the long-term adaptability of D.radiodurans in extreme environments.

Phosphorus removal from surface water is a key to control eutrophication issues. Among phosphorus removal strategies, clay adsorption materials have been studied widely due to various advantages. Yet, raw montmorillonite (MMT) has limited adsorption capacity for phosphate. In order to improve the adsorption performance of MMT for phosphate, aluminum polycation Al30 was used as a pillaring agent to modify MMT material, and response surface method was used to optimize the preparation process. The optimal conditions were obtained as: [OH−]/[Al3+] molar ratio of 2.4:1, Al/MMT ratio of 4:1, curing time of 12 h, reaction temperature of 77.5 °C, and alkali adding rate of 1.55 mL/min. After modification, the properties of MMT were improved obviously and the adsorption of phosphate in solution was enhanced. Investigation results indicate that the acid environment is more favorable for the adsorption of phosphate by Al30-MMT. The adsorption of phosphate by Al30-MMT accords with Langmuir model with maximum adsorption of 62.5 mg/g at 318 K and pseudo-second order kinetic model. The main adsorption mechanisms of Al30-MMT in the process of phosphate removal include electrostatic physical adsorption and anion exchange.

An aerobic, Gram-stain-negative, rod-shaped and motile strain, designated SCS-3T, was isolated from deep-sea sediment of the South China Sea. Phylogenetic analysis based on the 16S rRNA gene sequence similarities revealed that strain SCS-3T represented a novel species of the genus Devosia, with closely related strains 'Devosia sediminis' MSA67T (98.61 %), Devosia riboflavina IFO13584T (98.22 %) and Devosia indica IO390501T (97.72 %). The G+C content of the genomic DNA is 63.44 mol%. The digital DNA-DNA hybridization values with 'D. sediminis' MSA67T, D. riboflavina IFO13584T and D. indica IO390501T were 24.50, 21.8 and 24.80 %, respectively. The major polar lipids of strain SCS-3T were diphosphatidylglycerol, phosphatidylglycerol and three unidentified glycolipids. Ubiquinone-10 was the sole isoprenoid quinone, and C16 : 0, C18 : 1ω7c 11-methyl and summed feature 8 (C18 : 1 ω7c and/or C18 : 1 ω6c) were the major fatty acids. Based on polyphasic taxonomic data, strain SCS-3T represents a novel species of the genus Devosia, for which the name Devosia salina sp. nov. is proposed. The type strain is SCS-3T (=JCM 34403T=GDMCC 1.2221T).

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The synthesis of a series of novel, unsymmetrically substituted benzothiadiazole-containing vinyl monomers and their free radical polymerization with and without the control of a reversible addition−fragmentation chain transfer (RAFT) agent is reported. The resulting polymers with electroactive pendants show tunable absorption and emission spectra depending on their molecular architecture. Using RAFT allows the synthesis of block copolymers using a hole-transporting vinyl-triarylamine as a second monomer. Efficient energy transfer between the two pendants has been detected. Cyclic voltammetry and photoelectron spectroscopy in air measurements have been employed to reveal the location of the HOMO and LUMO of the block copolymers. The block copolymers also influence the morphology of spin-casted films and show rectifying behavior in organic photovoltaic devices.

Graphene-based materials have received worldwide attention in the focus of forefront energy storage investigations. Currently, the design of novel three-dimensional (3D) graphene structures with high energy capability, superior electron and ion conductivity, and robust mechanical flexibility is still a great challenge. Herein, we have successfully demonstrated a novel approach to fabricate 3D assembled graphene through the supramolecular interactions of β-cyclodextrin polymers (β-CDP) with an adamantine end-capped poly(ethylene oxide) polymer linker (PEG-AD). The incorporation of PEG-AD linker into rGO sheets increased the interlayer spacing of rGO sheets to form 3D graphene materials, which can provide efficient 3D electron transfer pathways and ion diffusion channels, and facilitate the infiltration of gel electrolyte. The as-prepared 3D self-assembled graphene materials exhibit significantly improved electrochemical performances of supercapacitor in terms of high specific capacitance, remarkable rate capability, and excellent cycling stability compared to pristine reduced graphene oxide. This study shed new lights to the construction of three dimensional self-assembled graphene materials and their urgent applications in energy storage.

Lithium-sulfur (Li-S) batteries, as a prospective energy storage system, are still plagued by many problems that prevent them from their application, especially the low content of sulfur in the cathode. Herein, a cathode material with S up to 93 wt % is designed via a hollow donor-π-acceptor heterosystem, which combines catalytic sites, adsorption sites, and good conductivity together. Following this guidance, a hollow porous carbon sphere is prepared with CoO particles and single V atoms decorated on it (Co/V-HPCS), providing ultrahigh volumetric space for sulfur. Even the electrode made of sulfur-loaded Co/V-HPCS (Co/V-HPCS@S) has a high content of 90 wt % (sulfur content in the electrode is ∼83.5 wt %), and the cathode exhibits an excellent discharge capacity of 575.2 mAh g-1 under 0.2C after 100 cycles. With careful analysis by means of a high-resolution transmission electron microscope (HRTEM), the catalytic amounts of CoO particles and single V atoms loaded on the carbon shell are confirmed, which endows the material with outstanding catalytic ability to transfer sulfur and excellent adsorption of polysulfides. This concept of the cathode material increases the possibility of advanced long-life Li-S batteries with high tap density and high energy density.

Two-dimensional transition metal dichalcogenides have been regarded as cheap and abundant catalysts for driving electrolysis of water. Using density functional theory methods, we systematically investigate the hydrogen evolution reduction of metal dichalcogenides/graphene heterostructures (MX2/Gs, M = Mo, W; X = S, Se) with various defects, MX2/G_VX, MX2/G_VM, and MX2/G_V(M+X). We find that such defected MX2/Gs show better hydrogen evolution reactive activities than pure MX2/Gs as well as freestanding MX2 monolayers, due to the metallic states induced by the defects. Particularly, MX2/G_VXs with a S(Se) vacancy display catalytic performance comparable to that of Pt. Moreover, the catalytic performance for the hydrogen evolution reaction of most defected MX2/G_VMs and MX2/G_V(M+X)s varies with H coverage and the M vacancy concentration. Our results provide a feasible way to apply MX2/graphene heterostructures to water electrolysis for hydrogen production.

Biochar often undergoes multiple thermal processes. Thermal evolution is described in this study as the process by which biochar in the environment changes again in a thermal environment. In this study, the thermal evolution process of biochar was studied by characterization test. The results showed that the oxygen content in biochar increased after thermal evolution, mainly due to functional groups such as O-H and C-O, while the functional groups of CO did not change significantly. Micro-pores will be generated in biochar after thermal evolution, which will increase the surface area and significantly enhance the adsorption capacity. The biochar was added to natural water to observe how biochar enhanced the removal of dissolved organic carbon (DOC). The concentration of DOC was reduced by about 6.68 mg/L by SB 800, and most of the components were humus, which indicated that the thermal evolution of biochar promoted the removal of DOC. The Electron spin resonance (ESR) test shows that after thermal evolution, biochar has more oxygen-containing carbon center persistent free radicals due to the increase of C-O functional groups in biochar. Under visible light, persistent free radicals in oxygen center are formed by electron transition, which can undergo a variety of reactions with water to form reactive oxygen species.

Lithium-sulfur batteries (LSBs) have been holding a great potential to serve as high energy density power source in advent of "carbon neutrality" era. However, LSBs nowadays still suffer from the notorious shuttle effect of polysulfides and sluggish redox reactions involving multiphase conversion. Herein, three-dimensional boron nitride (3D BN) with hierarchically porous architecture was innovatively constructed and incorporated into carbon cloth (CC) by means of vapor-assisted spatial growth (denoted as 3D-BN@CC). The as-prepared 3D-BN@CC sulfur host with highly exposed BN active sites exhibits strong adsorption and efficient catalysis toward soluble polysulfides. To further block the polysulfides leaking-out, an ultrathin composite layer composed of graphene (Gr) and nanocellulose (NC) is deliberately coated onto commercial separator (labeled as NC@Gr separator). LSB equipped with S/3D-BN@CC cathode and NC@Gr separator delivers a reversible capacity of 850 mAh/g with a high S loading of 5.36 mg cm−2. The approach developed in this work to create sophisticated 3D BN scaffold for S and sheds lights on the superiority of 3D-BN@CC in anchoring and catalyzing polysulfides to finally lead to high-performance LSBs.