Muhammad Irfan Asghar

A mass separator for unslowed fission products is installed at the high-flux reactor at Grenoble. Well resolved mass spectra are obtained in the light and heavy fission-product groups.

The CMS detector team describes their experiment and observation of decay products from a standard model Higgs boson, allowing its mass to be determined.

A series of chitosan (CS) and montmorillonite (MMT) clay based polyurethane bio-nanocomposites were synthesized by step growth polymerization; reacting hydroxyl terminated polybutadiene (HTPB) and toluene diisocyanate (TDI) to improve thermal and antibacterial properties of polyurethane (PU). Five different PU samples were prepared by varying mole ratio of CS and 1,4-butane diol (from 0 to 2 mol). Structural studies of PUs through FTIR and 1H NMR spectroscopy confirmed the incorporation of CS into the polymer matrix. The scanning electron microscope (SEM) analysis confirmed well dispersion of MMT clay into the PU matrix. Thermogravimetric analysis (TGA) of PUs indicated significant enhancement of thermal stability of PU with addition of CS. Antibacterial properties of PUs were measured by disc diffusion method; showed excellent potential against the selected strains. On the whole, CS showed potential to improve the antibacterial and structural properties of PU significantly; which might be precursor for biological applications.

The ion optics and optimal performance of the recoil separator Lohengrin are described. In order to investigate nuclear charge distributions of the fission products several techniques have been developed and their features are discussed. For nuclear spectroscopy of the fission products it was necessary to concentrate the activity spread along the 72 cm length exit slit of the instrument and this has been achieved by a fast moving tape collector and an air-jet system.

The first results are reported on the Pn values obtained with the recoil focussing parabolatype mass separator for unslowed fission products Lohengrin installed at the Grenoble high flux reactor. The mass chains studied were 90, 91, 93, 94, 95, 99, 134, 137, 138 and 139. Both the neutron and the β activities were measured simultaneously. The technique used to measure the neutron and the β activities and the method of analyzing the experimental data are discussed in detail. The present work led to: (i) three new periods corresponding to the new isotopes of selenium (91Se, T12 = 0.27±0.05 sec), strontium (99Sr, 0.6±0.2 sec) and telurium (138Te, 1.3±0.3 sec); (ii) accurate periods of 99Y(T12 = 1.45±0.22 sec) and 134Sn (0.7±0.2 sec); (iii) four new delayed neutron precursors consisting of 91Se, 94Kr, 99Sr and 138Te; (iv) six new Pn values corresponding to the precursors 91Se (Pn = (21±10)%), 94Kr ((5.7±2.2)%), 99Sr ((3.4±2.4)%), 99Y ((1.2±0.8)%), 134Sn ((17±13)%) and 138Te ((6.3±2.1)%); (v) a precise Pn value of the precursor 137Te ((2.5±0.5)%); (vi) a redetermination of the Pn values of the precursors 90, 91Br, 93Kr, 93, 94, 95Rb and 137, 138, 139I. The results of this work are discussed and compared with the existing data. The low level sensitivity of the present detection system is determined to be Pn(m)Yq(m) ⪆ 0.4 × 10−6 n/f (where Yq(m) is the cumulative yield for the mass m and the ionic charge q).

The pulse height defects for fission fragments separated according to their kinetic energies and masses are determined for a heavy ion silicon surface barrier detector operated at various applied biases. A discussion of the results in LSS dimensionless units is included. Several versions of a model are developed to relate the field dependent contribution of the defect due to charge recombination to the lifetimes of the charge plasmas formed in the wake of the fragments. Estimates are hence made from our defect data and plasma lifetime data (obtained elsewhere) of the plasma column initial radius (3 μm) and of the charge recombination lifetime in the track vicinity (20–50 μs at low charge densities). The recombination defect expressed as a fraction of the fragment energy is for heavy fragments up to three times that for light fragments. The resulting low prediction for the recombination lifetime may be correlated with the greater crystal damage created by heavy fragments.

Gamma spectra and half-lives of 100Y, 100Zr, 149Ce, 149Pr, 150Ce, 150Pr, 135 Te, 136Te, 137Te, 85Se, 86Se, 87Se and 88Se have been measured using the unslowed fission product separator Lohengrin. The ground state beta branching has been measured for the decays of 85Se and 88Br.

In the present topical mini-review, the beneficial impact of small-sided game football training for the increasing elderly global population is presented. As a multicomponent type of physical activity, football training executed on small pitched with 4-6 players in each team is targeting a myriad of physiological systems and causes positive adaptations of relevance for several non-communicable diseases, of which the incidence increases with advancing age. There is strong scientific evidence that this type of football training promotes cardiovascular, metabolic and musculo-skeletal health in elderly individuals. These positive adaptations can prevent cardiovascular disease, type 2 diabetes, sarcopenia and osteoporosis, and lower the risk of falls. Also, football training has been proven an efficient part of the treatment of several patient groups including men with prostate cancer and women after breast cancer. Finally, regular football training has an anti-inflammatory effect and may slow the biological aging. Overall, there is a growing body of evidence suggesting that recreational football training can promote health in the elderly.

Abstract Lettuce is an important crop that is grown commercially for salad purposes. To increase production of lettuce, synthetic fertilizers are applied. However, an excess of synthetic fertilizers is hazardous for the human body and also affects soil and environmental conditions. Alternative methods are available to enhance the production of lettuce, e.g., application of moringa leaf extract (MLE), which is also environmentally friendly. As MLE is a plant-based organic product, there are no side effects. The research was conducted at the Ornamental Nursery, Department of Horticulture, University of Agriculture Peshawar, during the 2020–21 season. The study was laid out in two-factor randomized complete block design in a split-plot arrangement with three replications. The two factors were MLE concentration (0, 2, 4, 6, and 8% v/v) and five lettuce cultivars (Red Laurel, Red Oakleaf, Milky White, Romaine, and Large Speed). Lettuce cultivars were sprayed with the required MLE concentrations at 2, 4, and 6 weeks after transplantation, while an extra application of MLE was given before bolting to the plants left for seed production. It was observed that lettuce cv. Red Laurel produced maximum fresh and dry head weight. Maximum plant height was recorded for cv. Red Oakleaf. Maximum leaves, head diameter, head height, root length, seed yield, and leaf area were noted in cv. Milky White. Cultivar Romaine took the maximum number of days to flowering and seed production. It also provided maximum chlorophyll content and the best taste. Moreover, MLE also had substantial effects on the growth and yield of lettuce cultivars. Here, maximum plant height, leaf area, number of leaves, head diameter, days to flowering, root length, head height, seed yield, days to seed production, chlorophyll content, and fresh and dry head weights were produced by plants sprayed with 8% (v/v) MLE. It is concluded that MLE, a useful growth promoter, has a considerable effect on the growth and development of lettuce cultivars and is thus recommended for organic production of the crop.

Magnetic iron oxide (Fe3O4) and its composite with graphene oxide (Fe3O4-GO) were synthesized via ultrasonic-assisted co-precipitation method and characterized by Scanning Electron Microscopy, Fourier Transform Infrared spectroscopy and x-ray Diffraction techniques. These magnetic catalysts were investigated as heterogeneous photo-Fenton catalysts to degrade selected pesticides (carbofuran and nitenpyram) under UV light. The detailed parametric study explained that optimum catalyst dose and oxidant concentration were responsible for better catalytic degradation of pesticides. Degradation studies using magnetite alone was also performed in order to visualize the role of GO in catalysis. The composite Fe3O4-GO performed excellently in comparison to Fe3O4 for pesticides degradation. More than 90% degradation of nitenpyram and carbofuran were achieved. In order to have deep insight of the interaction between various process parameters, optimization through Response Surface Methodology (RSM) was studied for Fe3O4-GO. It has been found that no iron hydroxide sludge is formed when using Fe3O4-GO. Also the catalytic degradation could be reproduced in consecutive experiments without a significant loss in the process efficiency.

Abstract Mesoporous silica (MPS) and MPS-Fe composite was prepared via sol–gel technique and characterized by BET, FTIR, XRD, SEM and pZc. The MPS and MPS-Fe adsorption efficiencies were evaluated for a cationic dye Turquoise-blue X-GB. The MPS-Fe composite showed pore size and BET values of 9.52 nm and 309 m 2 /g, respectively. XRD and SEM analysis revealed the amorphous nature and uniform distribution of spherical partciles with average particle size of 50 nm of MPS-Fe composite. The points of zero (pZc) charge found to be 2.3 and 6.3 for MPS and MPS-Fe, respectively. The MPS and MPS-Fe showed promising efficiency for the adsorption of Turquoise-blue X-GB as a function of medium pH, contact time, dye initial concentration and temperature. Among, Freundlich, Langmuir, Harkins–Jura, Temkin, Doubinin–Radushkevich isotherms, the Turquoise-blue X-GB followed Langmuir isothermal model with adsorption capacities of 83.34 mg/g and 74.07 mg/g for MPS and MPS-Fe composite, respectively. Among kinetics models, pseudo second order kinetic model fitted to the dye adsorption with R 2 values of 0.998 and 0.988 for MPS and MPS-Fe composite, respectively. The negative values of enthalpy (ΔH) and free energy (ΔG) revealed exothermic and spontaneous adsorption of dye at room temperature. Results revealed that MPS and MPS-Fe composite have promising potential for Turquoise-blue X-GB dye adsorption and could possibly be extended for the adsorption of dyes from textile effluents.

The recoil mass spectrometer Lohengrin of the Laue-Langevin Institute, Grenoble, has been used to measure the yields of light fission products from 249Cf(nth, f) as a function of A, Z, the kinetic energies and the ionic-charge states. The mass and nuclear-charge distributions integrated over all the ionic-charge states were determined for different kinetic energies ELoh between 87 and 112 MeV. The behaviour of ΔZ = Z−ZUCD as a function of A' differs strongly from that for 236U and 240Pu; it passes the zero value at ~7.5 mass units away from the center of the Z = 50 shell and it reaches ΔZ ∼ 1 at A' ∼ 123 without ever passing the shell. The mean proton and neutron odd-even effects on yields are δp = (4.6 ±0.7)% and δn = (9.5 ±0.7)%. The odd-even effects on mean proton and neutron kinetic energies are δEKo−e(Z) = (0.20 ± 0.07) MeV and δEKo−e(N) = (0.48 ± 0.16) MeV, respectively. The mean value of isobaric variance 〈σZ2〉 = (0.43 ± 0.03) and, unlike the results for 236U and 240Pu it shows little dependence on kinetic energy; the present value along with the results for the other fissioning nuclei confirm that σZ2 results from zero-point isovector giant dipole vibration at the exit point.

Fission fragment mass and kinetic energy distributions and mass-versus-energy correlations have been measured for the thermal neutron induced fission of 239Pu and 235U. Unwanted events were eliminated by a coherence test based on time of flight. The global mass distribution for 239Pu shows much weaker fine structure than 235U. However, for events with high total kinetic energy this fine structure becomes more prominent and the yield of mass 135 dominates for 239Pu compared to mass 134 for 235U. Moreover, a prolate deformation for mass 102 in the 134102 mass ratio for 235U is compatible with the data. The results show that EK(μH), hence EL and/or EH for 239Pu and 235U in the high mass yield regions have low energy tails produced in the act of fission. Furthermore, the data suggest that most of the proton pairs are broken after the effective determination of the structure of the nascent fragments and probably just before and/or in the act of scission itself.

Cyclodextrins (CDs) have attracted great interest from the research community as well as industries in an array of sectors because of their unique structural features. This book provides a comprehensive overview of CDs, beginning with their historical background. Chapters address such topics as the structure and physiochemical properties of CDs, advancements in the field, and potential applications of these materials in fields such as drug delivery and sensing. This book reveals new frontiers in the CD world and is a useful resource for organic, analytical, and supramolecular chemists as well as scientists engaged in biological and material sciences.

A gas ΔE − ER telescope has been used to measure charge yields and their correlations with kinetic energies for 229Th and 232U. Even-charge yields are enhanced compared with odd-charge yields for both fissioning systems; this enhancement increases for events with higher kinetic energy. The mean odd-even effect δp is = (40±4)% for 229Th; it is (21 ± 3)% for 232U-the same as for233U((22.1±2.1)%) and 235U((23.7±0.7)%). The energy-integrated δp and δp for different energy windows, vary strongly as a function of charge (Z) due to the underlying shells. The δp averaged over Z increases fast with kinetic energy, contrary to the existing results for 233U and 235U, where δp flattens off at low energies. For both systems, the most probable kinetic energy Ē shows a strong odd-even stagger; the mean odd-even effect on energy, δEKo−e, is 1.4 ± 0.3 MeV for229Th, and 1.7±0.4 MeV for 232U — the latter is about twice the value for 233U (0.95 ± 0.09 MeV) and 235U (0.7 MeV). These results are discussed in terms of the existing models.

Fragment-mass and kinetic-energy distribution measurements for 252Cf(sf) have been extended to the far-out asymmetric low-yield fission region of MH = 190 compared with the existing data that go up to MH ≈ 168. The mass yield Y(m) shows a shoulder for MH ≈ 163 and an important enhancement for MH ≳ 176. The 〈EK〉(m), σEK(m) and, to a lesser extent, Y(m) distributions show strong and correlated amplitude fluctuations for MH ≳ 170. These data indicate strong and rapid changes in deformation of the nascent fragments and the coexistence of more than one deformed-shell stabilized scission configuration for the same mass splits. These structures and those present in the relatively high-yield regions are discussed in terms of the static macro-microscopic potential-energy calculations.

Granite is an igneous rock that contains natural radioactivity of primordial radionuclides. In Pakistan, granite is distributed in a vast area called the Ambela Granitic Complex (AGC) in North West Frontier Province (NWFP). Granite is a hard rock that exists in different colours and is used to decorate floors, kitchen counter tops, etc. The use of granite in a building as a decor material is a potential source of radiation dose; therefore, natural radioactivity has been measured in 20 granite samples of the AGC with an HPGe (high purity germanium) based gamma ray spectrometer. The average specific activities and their range (given in parentheses) for primordial radionuclides (40)K, (226)Ra and (232)Th were 1218 (899-1927), 659 (46-6120) and 598 (92-3214) Bq kg(-1), respectively. The measured activity concentrations were used for the assessment of hazard indices and radiation dose which were evaluated based on the permissible limits defined for these parameters. The measured specific activities and the derived quantities, hazard indices and radiation dose, have been compared with those given in the literature for these parameters.

Fission fragments provided by the mass separator “Lohengrin” were slowed down in a homogeneous 1.2 mg/cm2 thick carbon absorber. By measuring the residual energy with a time-of-flight method, a resolution of Z/ΔZ = 45 at Z = 40 was achieved.

In order to investigate the radiological hazard of naturally occurring radioactive material (NORM) in phosphorite deposits of Pakistan, 26 samples of phosphorite were collected from the phosphorite mines near Abbottabad, and 20 samples of single superphosphate (SSP) fertilizer were obtained from the warehouses in Pakistan. Activity concentration in all the samples was assayed using HPGe detection system. Specific activity values of 238U, 40K, 226Ra and 232Th in the samples of phosphorite were 550 ± 156 (329–845), 206 ± 72 (93–362), 511 ± 189 (316–830) and 52 ± 17 (23–81) Bq kg−1, respectively; and those in SSP fertilizer due to these radionuclides were 637 ± 44 (596–687), 164 ± 24 (113–215), 589 ± 44 (521–671) and 29 ± 6 (16–45) Bq kg−1, respectively. The results were compared with that of worldwide soil. Outdoor external dose rate due to gamma rays from phosphorite was calculated to be 276 ± 94 (177–441) nGy h−1 and external dose rate in a room made of phosphorite containing material was estimated to be 706 ± 243 (455–1129) nGy h−1. The concentration of radon was measured in phosphorite mines and in the warehouses for SSP fertilizer by an active method. Protective measures have been proposed to control the pollution in the phosphorite mining and processing, and fertilizer storage areas.

The nuclear charge distribution of mass separated monoenergetic fission products of the isobaric chains 90 and 91 were recorded with a ΔE Si-surface barrier detector. The achieved nuclear charge resolving power (fwhm) ZΔZ was 43.

The energy and angular distributions of the long-range α-particles released in the thermal neutron induced fission of 235U have been measured as a function of the mass and kinetic energy of the fission fragments. Only one of the fission fragments was detected, its mass being determined by kinetic energy and time-of-flight measurements. The dependence of the light particle kinetic energy spectra on its final direction is examined as a function of mass and kinetic energy of the fission fragments. The angular distribution of all α-particles with respect to the light fragment direction has a most probable value of 81.3°±0.5° with a dispersion (FWHM) of 18.5°±0.8° which compares very well to the angular spread measured in the spontaneous fission of 252Cf. Other striking similarities between the ternary fission of 236U and 252Cf are pointed out. A positive correlation between the mean emission angle and the mass of the light fragment resolves the controversy which remained on this point up to now. The influence of the total fragment kinetic energy on the width of the angular distribution is investigated in detail. A preliminary interpretation of our data shows that α-accompanied fission should no longer be considered as contradictory to the semi-statistical models of fission.

The neutron total, capture and scattering cross sections of thorium have been measured in the neutron energy range from about 15 eV to 1 keV by the time-of-flight method. The neutron and radiation widths of the larger resonances have been determined by combining the data from the three types of measurement. The small but significant fluctuation observed in the radiation widths about a mean value of 21.5 meV is discussed. The value of the infinite dilution resonance integral of 79±4 b calculated from these resonance parameters is in agreement with recent measurements.

Synthetic dyes are widely used in textile, leather and other dye-stuff industries.A large fraction of the dyes applied during the dyeing processes are released into wastewater.Therefore, the wastewater from dye-related industries is densely colored, with high chemical oxidation and biological oxidation demand.This wastewater must be treated prior to discharge into wastewater streams to prevent pollution of surface and groundwater, and minimizing risks to public health.The present study was undertaken for the first time in Pakistan to optimize the factors for algae possessing high potential to degrade Reactive Blue azo dye in liquid medium.Among eighty eight (88) isolates of alga, two showed high decolorization, which were used to optimize the decolorization of Reactive Blue azo dye.Both the selected algal strains showed an excellent potential to decolorize 100 mg L -1 Reactive Blue in seven days in the liquid broth.The optimum conditions determined for the two selected algal strains for decolorization of Reactive Blue (100 mg L -1 ) were pH 7.0, temperature 30°C, light conditions of 16 h, when inoculum size of 1 mL/10 mL was maintained and dye solution was supplemented with 5 g L -1 N and 5 g L -1 P as cosubstrates.

The increased awareness of people about deleterious effects of UV radiations to human health was the motivation to develop the UV protective textiles. This research was focused to computationally design and synthesize fiber reactive UV absorbers using cyanuric chloride as starting synthetic building block having s-triazine scaffold. The computational profile of design compounds included optimized geometries, photophysical properties, FT-IR and Raman vibrational frequencies which were investigated at DFT level using CAMB3LYP and B3LYP functionals with 631-G (d, p) basis set. The designed target compounds successfully synthesized and chemical structures were characterized by ESI-MS, UV–Vis, ATR-FTIR, and Raman spectroscopy. The results of computational and experimental spectroscopic techniques are presented in comparison that showed excellent correlation. The synthesized UV absorbers were applied onto cotton fabric through simple pad-dry-cure technique and their potential as textile UV protective agent was evaluated by measuring UPF and wash durability. The finished fabric with synthesized compounds offered UPF value of 170 and 129 for UVA1 and UVA2 respectively and was persistent with UPF values of 134 and 118 even after 25 home launderings. The finished cotton fabrics were characterized by ATR-FTIR after 25 home launderings to identify the presence of different functional groups. The cotton fabric finished with synthesized compounds proved its potential as highly UV protective with long wash durable textile.

Abstract An experiment was carried out to study the “Effect of different edible oil coating and storage life on post-harvest quality of banana fruit” at Post harvest Laboratory, Department of Horticulture, The University of Agriculture Peshawar Pakistan during the year 2021. Banana fruit CV. Cavendish was obtained from local market Peshawar brought from Hyderabad during the month of April 2021 at physiological mature stage. The experiment was laid out using Completely Randomized Design (CRD) with two factors repeated two times. The fruits were then kept in packaging materials with one apple per bunch. When the fruits were ripened were divided into two groups, one group was coated with edible oil (olive, coconut and butter) and the other is storage life (0, 3, 6, 9, 12) and kept at room temperature 26 0 C at RH 90–95% for 12 days. The data regarding banana fruits coated with butter oil showed maximum fruit firmness, titratable acidity, ascorbic acid content, fruit color score, fruit taste score and fruit decay percentage. The maximum TSS was observed in banana fruit coated with olive oil. Regarding the other mean for storage duration maximum fruit firmness, minimum fruit decay and minimum TSS was recorded in freshly ripened banana fruits. While maximum test score, and color score observed in fruits stored for 12 days. Most of the studied attributes were significantly affected by T × SD interaction. It is concluded from the present results that banana fruits harvested at physiological maturity ripened under natural ripening agent i.e. apple, coated with butter oil retained most of the quality attributes for 12 days, is recommended for better shelf life and consumer preferences.

Abstract A study on the “effect of sowing dates on lettuce yield, grown in the Open field and partial shade” was conducted at the Ornamental Nursery, Department of Horticulture, The University of Agriculture Peshawar, during 2020–2021. The randomized complete block design (RCBD) with a split-plot arrangement having two factors, replicated three times was used in the experiment. The lettuce ( Lactuca sativa L.), variety ‘Large Speed’ was grown in two growing conditions (open field and partial shade) at different sowing and transplanting dates, and their effect was studied. The seeds of lettuce were sown on six different dates i.e., 24th December 2020, 8th January, 23rd January, 7th February, 22nd February, and 9th March 2021. The results showed that the growing conditions and sowing dates significantly affected the growth and yield of the lettuce crop. Regarding the growing conditions, the plants grown in the open field produced maximum chlorophyll content, number of leaves plant − 1 , head diameter, head fresh weight, head dry weight, leaf Area, number of seeds plant − 1 , seed yield, and root length plant − 1 . On the other hand, maximum head height plant − 1 , days to flowering, days to seed production, plant height, and better taste were recorded in partial shade. In terms of sowing dates, maximum chlorophyll content, number of leaves plant − 1 , head height, head diameter, head fresh weight, head dry weight, leaf area, number of seeds plant 1 , seed yield, root length, taste, days to flowering, days to seed production and plant height were recorded for the plants of first sowing and transplanting date (24th Dec). These parameters decreased with delayed sowing and transplanting.

A new semi-empirical formula for the calculation of the (n, p) cross section at 14.5 MeV neutron energy is obtained. Derived from the evaporation statistical model, the new formula includes five parameters and shows for the first time a strong dependence of the (n, p) cross section on terms of the parameter (2Z−1)/A. Fitting this formula to the existing cross section data on 161 nuclei with 40≤A≤209, the adjustable parameters have been determined and the systematics of the (n, p) reaction have been studied. The predictions of this formula are compared with those of the existing formulae and with the experimental data. The formula with five parameters is found to give a better fit to the data than the previous comparable formulae.

The COSI FAN TUTTE spectrometer has been used to measure for the first time in one go the mass-charge-energy correlations for well-resolved light group masses for 229Th(nth, f). About 4.8 × 105 events were collected in a ≈ 3 months run. The global mass distribution shows structures and the distribution for EL = (112±0.5) MeV is dominated by mass numbers AL = 86 and 96. The mean kinetic energy 〈EL〉 shows strong fluctuations as a function of the light fragment mass AL. The mean proton odd-even effects in yields and energy are дp = (40.0±1.0)% and д Eo-eTKE = (1.35±0.17) MeV, respectively. The δp(EL) varies by a factor of ≈ 3 for EL = 02 to 107 MeV with a plateau for EtL ≈ 96 to 103 MeV. The mean neutron odd-even effect is δn = (1.95±0.5)%). The mean value of the conditional variance is 〈σ2 (Z¦A)〉 = (0.33±0.02) and it varies little with energy. The conditional variance seems to decrease as one goes from 252Cf to 230Th. These data are discussed in the context of existing results on other nuclei.

The surface of the cellulosic fabrics was modified using self-prepared emulsions of polyurethane acrylate copolymers (PUACs). PUACs were prepared by varying the molecular weight of polycaprolactone diol (PCL). The PCL was reacted with isophorone diisocyanate (IPDI) and chain was extended with 2-hydroxy ethyl acrylate (HEA) to form vinyl terminated polyurethane (VTPU) preploymer. The VTPU was further co-polymerized through free radical polymerization with butyl acrylate in different proportions. The FT-IR spectra of monomers, prepolymers and copolymers assured the formation of proposed PUACs structure. The various concentrations of prepared PUACs were applied onto the different fabric samples using dip-padding techniques. The results revealed that the application of polyurethane butyl acrylate copolymer showed a pronounced effect on the tear strength and pilling resistance of the treated fabrics.

Thin film technology has gained significant attention in the industry due to its superior properties in comparison to bulk materials. Specifically, iron nitride-based thin films are a fascinating area of research in semiconductor technologies. The crystal structure and optical properties of these films are highly dependent on the growth method, deposition technique, gas flow, pressure, and several other factors. In this work, we prepared polycrystalline thin films of iron nitride on silicon (100) substrates by using the active screen low temperature plasma-assisted method. These films are deposited under the varying atmosphere of nitrogen and hydrogen in four proportions: 80% N2 + 15% H2; 60% N2 + 35% H2; 40% N2 + 55% H2; and 20% N2 + 75% H2, along with 5% argon to investigate its influence on the structural, morphological, and optical properties. The structural properties are determined by x-ray diffraction and revealed a mixture of ζ-Fe2N, ε-Fe3N, and γ′-Fe4N phases. Surface morphology is analyzed by scanning electron microscopy, which confirms the formation of a thin layer on the substrate. In addition, UV–Vis spectrophotometry is used to assess the optical response and bandgap energy of the samples. The result of UV–Vis optical diffuse reflectance spectra shows a decrease in the bandgap from 3.17 to 3.06 eV of substrate. For the S4 sample, we obtained a pure Fe4N phase, showing a significant decrease in the energy bandgap.

Fission-fragment mass and kinetic energy distributions and their correlations have been measured for 232U and 233U. The results on these uranium isotopes and 235U are compared. The mass peak/valley ratio of 785 ± 68 for 232U is the highest of the three isotopes. The 〈EK〉(μH) distributions show significant differences. The dip ΔEK at symmetry is 16.2 ± 1.0 MeV (232U), 17.0 ± 1.0 MeV (233U) and 20.6 ± 1.1 MeV (235U). In the yields for high-kinetic-energy-selected events, the mass 134 dominates for 233U and 235U, but for 232U it is μH≈144, which dominates. This complete reversal of profiles can be understood in terms of fragment shells.

The α-particle ternary fission (LRA) and the binary fission of 235U with thermal neutrons have been studied with a multiparametric system. The aim was to get significant results ove: the whole mass range including the symmetric and the far-out asymmetric regions, where the yields are low and the contamination due to the spurious events is high. A technique has been used to eliminate the spurious events. Results are presented on the energy and the mass distributions in LRA fission and binary fission. A difference of 2.6 ±0.5 MeV is found in the mean total fission fragment kinetic energy for these two modes of fission. The α-particle probability Pα(M) is calculated under certain assumptions and compared with the prompt neutron ν(M) and the prompt γ-ray Nγ(M) yield data. Results are presented on Pα(R). There exists an anti-correlation between E¯α and ET: ∂Ēα/∂ET= -0.105±0.01, and between E¯T and Eα: ∂ĒT/∂Eα= -0.45±0.06. An effort is made to explain these various results either in a quantitative or in a qualitative way.

Neutron capture and neutron elastic scattering measurements have been made on 238U. These data are combined, and the resonance parameters Γn and Γγ, for 27 resonances in the energy range from 6.65 eV to 823 eV, are reported. The present value of s-wave strength function of (0.70±0.15) X 10−4, obtained from these parameters, is in reasonable agreement with the published values. Although the present values of Γγ have higher accuracy than the values reported by other authors, the errors are not small enough to draw any definite conclusions about the intrinsic spread in their values. The weighted mean value of Γγ is 23.74±1.09 meV where the error includes ±0.86 meV associated with the systematic uncertainties in the capture measurement. A standard deviation of 1.9±1.2meV was found for the assumed Gaussian frequency distribution of the total radiation widths.

The nuclear charge distribution of fission products with mass numbers A = 90, 91, 94, 99, 100, 101 and 104 provided by the mass separator “Lohengrin” was measured. Adjacent elements in the group of the light fission products could be separated by their different energy loss in a carbon absorber. The Z-yields were found to be strongly dependent on the kinetic energy of the fission products. The widths of the nuclear charge distributions are very small, in general, and strongly dependent on A as well as on the kinetic energy. The influence of the neutron evaporation and odd-even effects are clearly detected. An asymmetric nuclear charge distribution was found for A = 104 indicating the suppression of fission fragments with Z = 43. The average nuclear charges of the fission products at their average kinetic energy are in good agreement with the results from measurements of the number of β-decays and K X-ray measurements. The average nuclear charge of the isobar A = 132 was measured at its average kinetic energy with a calibrated secondary electron detector to be Z = 51.14 ± 0.15 which is in very good agreement with the radiochemical results. Thus previous physical measurements indicating a large independent yield for the doubly magic nucleus 132Sn could not be confirmed.

Fission fragment mass and kinetic energy distributions and mass-versus-energy correlations have been measured at the Grenoble high-flux reactor for the thermal neutron induced sub-barrier fission and above-the-barrier fission of 237Np and 235U, respectively. Unwanted events were eliminated by careful timing. In the case of 237Np(nth, f), the two odd particles (one proton and one neutron) are, on the average, shared out equally between the two complementary fragments leading to 〈μH〉, being 1 amu higher than the value for the neighbouring even-even fissioning nuclei. The peak mass yield for 237Np is 5.7 % compared to 6.5 % for 235U. The peak valley ratios of mass distribution are 124 and 544 for 237Np and 235U, respectively. The mass distribution for 237Np is wider than for 235U and broadens more towards more asymmetric fission than towards symmetric fission. The global mass distributions for 237Np and 235U show fine structures. For events with high total kinetic energy, the yield of mass around 136 seems to dominate for 237Np compared to mass 134 for 237U. The periods of the fine structures seem to be ≈ 2.5 amu and 5 amu for 237Np and 235U, respectively. The 〈EK〉 for 237Np is about 4 MeV less than the expected value. It is, respectively, ≈ 0, 5 and 1.5 MeV less for the mass regions μH≈ 119–124, 124–135, and 135 and beyond. It is shown that these results are qualitatively consistent with Nörenberg's model. However, it is shown that this model does not explain these results quantitatively.

Delayed-neutron emission probabilities Pn of 92,93Kr, 92,93Rb, 141,142Xe and 141,142Cs have been obtained using an on-line isotope separator. β- and neutron activities were measured with a 0·955 × 4π-β detector and a neutron detector whose efficiency of neutron detection was reasonably independent of neutron energy. All the possible corrections and errors were looked into and applied to the data. The precursors and Pn-values determined in this work are 92Kr, 0·0323%; 92Rb, 0·0125%; 93Kr, 1·92%; 93Rb, 1·164%; 141Xe, 0·0426%; 141Cs, 0·0529%; 142Xe, 0·406%; and 142Cs, 0·285%. These values are ∼2 to 3 times more precise than the existing data.

The “γ-ray multiplicity method” has been applied to low-energy resonances in 235U. Appropriate biases were set to minimise the effect of fission γ rays. The data on 24 resonances fall into two groups which are assumed to correspond to the two different spin states.

The reactions 89Y(p, γ) 90Zr, 88Sr(p, γ)89Y and 86Sr(p, γ)87Yhave been studied at 3930 keV proton energy. A pair spectrometer consisting of two NaI(Tl) crystals and a Ge(Li) diode was used to measure theθ-ray spectra. Six, four and five high-energy θ-ray transitions were observed respectively in 90Zr, 89Y and 87Y. The energies of these transitions, the proton separation energies Sp for each of these nuclei and proton-proton pairing energies δp for Z = 40 have been determined with high precision. The relative intensities and the values of absolute capture cross sections for various transitions were also determined. To interpret the results on 90Zr, it is necessary to assume the existence of 2p-2h configurations in the capturing 1− S = 0, L = 1; S = 1, L = 1 giant resonances. A value of 3.9 for the 2p-2h amplitude to the 1p-lh amplitude is determined. The 2+ levels at 3293 keV and 3827 keV in 90Zr are proposed to have respectively the [(2p32)p−2(lg92)p2][2+] and if[(1f52)p−2(1g92)][2+] configurations. In 90Zr s-wave proton capture dominates, therefore it is essential to invoke the existence of both s-wave and d-wave capture for 89Y (for 87Y perhaps, also) in order to explain the results. It is suggested that this important d-wave capture may be due to the presence of the wing of a proposed proton resonance at Ep ≈ 5 MeV, which should be an analogue to the ground state of 89Sr.

A new semi-empirical formula with five parameters has been derived to systematise the (n,p) cross section data of 14 MeV neutrons. It is based on the evaporation model and uses the Droplet model of Myers and Swiatecki to express the Q(n,p). The behaviour of the different terms of the Droplet model involved in Q(n,p) was checked individually before choosing the pertinent terms and setting up the formula. This relation leads to the lowest value of χ2 compared with the existing formulas, when used to correlate the experimental σ(n,p) data for 161 nuclei with 39⩽A⩽209.

A back-to-back ionisation chamber has been used to measure the fission fragment mass-kinetic-energy correlations for 248Cm(s, f). In all about 12 × 106 fission events were collected. The different distributions in the high-yield region are consistent with the existent data. As predicted by the theory of fission channels, the existence of far-out asymmetric fission has been confirmed, but its amplitude is much smaller than that for 252Cf(s, f) indicating that the barrier of the channel corresponding to this channel should be lower for 252Cf(s, f) than for 248Cm(s, f). Furthermore, the 〈EK〉(MH) and σEK (MH) distributions show correlated fluctuations in the far-out asymmetric region suggesting the existence of at least two scission configurations with different deformations for the same fragmentation. In the cold-fission region, the deformed neutron N ⋍ 88 shell dominates the yield.

Abstract The yields of 51 fission products in 36 mass chains produced in 238 Pu(n th , f) have been determined via γ-ray spectroscopy. The mean number of neutrons per fission was found to be 〈ν T 〉 = 2.5 ± 0.2. A mean proton odd-even effect δ p = (14 ± 3)% was also deduced for 9 mass chains. These results are discussed in terms of the existing data on other fissioning nuclei.

Delayed neutron emission to excited states in 84Se, 93Sr and 134Te has been investigated. Comparison of energies and intensities of neutron and γ-ray transitions observed in the decay of the precursors 85As and 135Sb leads to the localization of individual levels in the delayed neutron emitters, suggesting over and above high selectivity in β−-decay also selectivity in the subsequent neutron emission with substantially higher decay probabilities to excited states in the final nuclei than expected from energetics and angular momentum considerations. Gernmany.

Abstract Fission-fragment mass and kinetic-energy distributions and their correlations have been studied for the sub-barrier fission of the odd-odd 242 Am and 244 Am nuclei resulting from thermal neutron capture in 241 Am and 243 Am. Unwanted events were eliminated by a coherence test based on the time of flight. The 243 Am mass distribution is more asymmetric and shows structures at μ H ≈ 139 and 144, compared with that for 241 Am which is smooth and structureless. The structure at μ H ≈ 144 is caused by deformed neutron shells at N ≈ 88 in the heavy fragment and N ≧ 60 in the light fragment. While the 〈 E K 〉 at symmetry for 241 Am is ≈ 19 MeV higher than that for 235 U, it is shifted upwards only ≈ 6.5–10 MeV in the other mass regions. However, 〈 E K 〉 at symmetry for 243 Am is ≈ 6 MeV lower than for 241 Am and this decrease tapers down to ≈ 1 MeV for μ H > 135. These data show a decrease in the total fragment deformation for 241 Am at symmetry as predicted by calculations. However, the 243 Am data show a sudden change back to higher deformation.

Abstract Neutron scattering measurements have been made up to about 300 eV on 239 Pu. Combining these data with the published transmission data ( gΓ n , Γ ), spin assignments of 50 resonances have been made. If the resonances assigned by other workers are included, the average values of fission widths for 0 + and 1 + resonances up to 200 eV are found to be 479.4 and 37.6 meV, respectively. It is shown that this average value of fission width (37.6 meV) for 1 + resonances is inconsistent with the hypothesis of 1 + resonances fissioning through a 1 + two quasi-particle transition state and one needs a 1 + transition state at a much lower energy to account for this result. This state may be a 1 + combination transition state formed frommass asymmetry and bending vibrations.

New types of dyestuff moieties are being introduced to get the ease in imparting color to various substrates and sorting out the ways to improve the quality of dyed fabric using environmentally friendly techniques.To contribute to this research effort, the present study was carried for dyeing cellulosic fabric using novel bi-functional reactive dye.The synthesized dye contained sulphatovinylsulfone and monochlorotriazine functionality.The important influencing parameters for the exhaust method, e.g., dyeing temperature, concentration of salt, and alkali were optimized and their interaction was studied using central composite design.The results indicated that 61.5ºC was found to be suitable for the maximum exhaustion and fixation of the dye on cotton fabric.The optimum concentration of salt (30.01 g/L) and alkali (22.32 g/L) for dye experimentally resulted in 84.98 (±3)% of exhaustion and 79.00 (±3)% fixation on cellulose fabric.Fastness properties were good-to-excellent for the novel reactive dye applied on cotton fabric.A comparison of the results with the commercial reactive dye showed that attained results were within a practical range suitable for commercial dyeing.

Abstract A new semi-empirical formula with six parameters has been derived to systematise the (n,α) cross section data of 14.5 MeV neutrons. It is based on the evaporation model and uses the Droplet model of Myers and Swiatecki to express the Q(n,α). The behaviour of the different terms of the Droplet Model involved in Q(n,α) was checked individually before choosing the pertinent terms and setting up the formula. This relation leads to the lowest value of χ2 compared with the existing formulas, when used to correlate the experimental σ(n,α) data for 120 nuclei with 39⩽A⩽209.

The 40K(n, α)37Cl and 40K(n, p)40Ar reaction cross sections were measured in the neutron energy region from 0.02 eV up to about 70 keV. The proton and α-particles were detected with a large surface barrier detector, and the neutron energy was measured by time of flight. The reaction cross sections show a pronounced resonance structure. A comparison of the density of s- and p-wave resonances (compound spins between 52 and 112 in 40K + n to the density of spin − 52 compound states observed as resonances in the reaction 40Ar + p by Keyworth et al., allows a direct determination of the spin cut-off parameter of the level density.

A new semi-empirical formula with five parameters has been derived to systematize the (n,t) cross-section data of 14.5 MeV neutrons. It is based on the evaporation model and uses the droplet model of Myers and Swiatecki to express the Q(n,t). The behavior of the different terms of the droplet model involved in Q(n,t) was checked individually before choosing the pertinent terms and setting up the formula. This relation leads to the lowest value of χ2 compared with the existing formulae, when used to correlate the experimental σ(n,t) data for 25 nuclei.

The pulse height defects for fission fragments separated according to their kinetic energies and masses were determined for a heavy ion silicon surface barrier detector. The experiment used the fission fragment mass separator ‘Lohengrin’ at ILL Grenoble. The data recording system is described. The light fragments defects plotted against energy in LSS dimensionless units fall progressively further with decreasing mass below a universal curve which has been previously used for other ions and on which all the heavy fragment data fall. The fwhm of the defect, being accountable largely to atomic collisions and being less mass dependent than the defect itself, indicates that this strong mass dependence in the defect for light fragments is due to other causes than atomic collision losses. The contribution to the defect due to charge recombination is determined by subtraction from the observed defect of calculated detector window losses and atomic collision losses. The dependence of the recombination defect on fragment atomic number, Z1, (or mass) and electronic stopping power is compared with the predictions of various models. Fragment atomic shell effects including Z1 oscillations in the stopping power can explain the light fragment behaviour of the defect.

A method based on time-of-flight is described to separate the fission fragment masses with a mass resolution of better than 1 amu. Experimental results are presented. Its zone of applicability and the factors that control it, are discussed. The mass yield of 235U(nth, f) is compared with the data from the Lohengrin mass separator.

The nuclear charge distribution of fission products from $^{235}\mathrm{U}({n}_{\mathrm{th}}, f)$ is determined for the isobaric chains 92 to 100. The results were obtained from the energy loss of monoisobaric and monoenergetic fission products in a $\ensuremath{\Delta}E$ Si surface-barrier detector. The odd-even effect is found also in the mass chains reported here for the first time, revealing an approximately sinusoidal variation of the charge distribution width with mass.

Abstract Neutron resonance scattering and capture measurements have been made on 165 Ho (I = 7 2 ) using a variety of sample thicknesses. On the basis of a χ2 test, the spins of eight resonances have been assigned and five more given tentative spin assignments. An additional six resonances were given tentative spin assignments on the assumption that the Γγ does not fluctuate significantly from resonance to resonance. The present results are compared with the assignments of other workers. The values of total radiation widths Γγ do not show any significant fluctuations from the weighted mean value of 75.7±2.4 meV. The measurements of the average capture cross section from 0.5 keV to 100 keV are given, and these data are respectively lower than the published values of capture cross section (at 30 keV and 60 keV) obtained with a liquid scintillation tank and higher than the value (at 24 keV) obtained using an activation method. However, our data are in very good agreement with the Russian data obtained using the lead slowing down neutron spectrometer.

Abstract A detector for the measurement of neutron elastic scattering cross sections in the resonance region is described. The detector consists of five lithium-loaded glass scintillators assembled into two groups, the scintillators in the first group having a 6 Li content 46 times greater than those in the second. The response of the two groups to gamma-rays is matched as closely as possible so that when the output of the second group is subtracted from that of the first, the effective sensitivity of the system to gamma-rays is close to zero. Measurements on 169 Tm, 197 Au and 232 Th demonstrate that scattering cross section data accurate enough to determine resonance spins may readily be obtained.

The resonant scattering method in combination with the available transmission data and the gamma-ray cascade technique have been used to determine the spin values of compound nuclei 156Gd and 158Gd resonances. While scattering measurements were made on both enriched isotopes of 157Gd and natural Gd, only natural Gd was available for the γ-ray cascade experiment. Altogether 29 and 24 spin assignments have been made for 155Gd and 157Gd respectively. The distribution of spins is consistent with the (2J+1) law. The values of s-wave strength function for each spin state are for 155Gd, (S0)J = 1 = (1.38 ±0.73) × 10−4, (S0)J = 2 = (1.72±0.60) × 10−4, and for 157Gd, (S0)J = 1 = (2.94±1.56) × 10−4 and (S0)J = 2 = (2.26±0.88) × 10−4. Within the statistical errors, these values show no spin dependence of the s-wave strength function.

Abstract The Cosi-Fan-Tutte spectrometer has been used to measure for the first time in one go the mass-nuclear charge-energy correlations of well-resolved light group masses for 239 Pu(n th , f). About 2 × 10 6 events were collected and analysed. The global mass distribution is consistent with the Lohengrin data. The mean proton odd-even effects in yields and energy are δ p =(11.8±0.3)% and δE K o −e=0.49±0.15 MeV respectively. The δ p ( E L ) varies from ≈7% to ≈25% for E L =90 to 116 MeV. The present analysis consists of 21 values of E L compared to only 5 values for Lohengrin. The apparent mean neutron odd-even effect δ n =(3.5±0.1)% is much lower than the δ n = (6.5±0.7)% for Lohengrin. The mean value of conditional variance 〈 σ z 2 ( Z | A )〉=(0.42±0.02); the 〈 σ z 2 ( Z | A )〉 increases from 230 Th to 250 Cf and this behaviour turns out to be important for understanding the dynamics of the fission process.

Abstract Fission-fragment mass and kinetic energy distributions and their correlations have been measured for 238Pu(nth, f). The mass distributions for 238Pu, 239Pu and 241Pu are similar — smooth and featureless — suggesting that proton pairing effect in 238Pu(nth, f) is low as for the other two Pu isotopes. The peak/valley ratio is 250 ± 19 for 238Pu compared with 141 ± 10 for 239Pu and 315 ± 29 for 241Pu. The dip ΔEK values at symmetry are 16.6 ± 0.8 MeV ( 238 Pu ), 21.2 ± 0.6 ( 239 Pu ) and 21.9 ± 1.3 MeV ( 241 Pu ) . The 〈EK〉 (μH) distributions show some differences. There are some structures for high kinetic energy selected events.

Abstract The recoil mass separator LOHENGRIN of the Laue-Langevin Institute Grenoble has been used to measure for the first time, the yields of light fission fragments from the fissioning system: 239 93 Np; this odd-Z nucleus is formed after double thermal neutron capture in a 239 93 Np target. The mass distributions were measured for different kinetic energies between 92 and 115.5 MeV, but the nuclear charge distributions were determined only up to 112 MeV. These distributions are compared to the distributions obtained for the even-even system 240 94 Pu. At high kinetic energy, the mass distribution shows a prominent peak around mass number A L = 106. These cold fragmentations are discussed in terms of a calculation based on a scission point model extrapolated to the cold fission case. As expected for an odd- Z fissioning nucleus, the nuclear charge distributions do not reveal any odd-even effect. The global neutron odd-even effect is found to be (8.1 ± 1.5)%. A simple model has been used to show that most of the neutron odd-even effect results from prompt neutron evaporation from the fragments.

Fission fragment mass and kinetic energy distributions and mass-versus-energy correlations have been measured for the thermal neutron induced fission of 231Pa. The global mass distribution and the mass distribution for selected kinetic energy events show fine structure with a mean period of ≈ 2.5 amu. The peak/valley ratio of the mass distribution is 2271 ± 854 compared to 554 ± 31 for 235U. The dip ΔEK values at symmetric fission for 231Pa and 235U are 14.8 ± 4.2 and 20.6 ± 1.1 MeV respectively. The 〈EK〉(μH) for μH ≈ 125–135 is flatter than for 235U.

Some characteristics of the thermal-neutron-induced fission of 231Pa, 232Th and 237Np were studied using a highly pure thermal-neutron beam of the Grenoble High Flux Reactor. For the thermal-neutron-induced-fission cross section we obtained 20 ± 4 mb for 237Np, 19 ± 4 mb for 231Pa and less than 2.5 μb for 232Th, in agreement with calculations based on a double humped fission barrier. We also determined a mean total fission fragment kinetic energy of 172.8 + 2.5 MeV for 237Np, which fits into the semi-empirical systematic of ĒK versus Z2/Acase13. Finally, we determined LRA/B ratios of (1.94±0.17) × 10−3 for 237Np and (1.67±0.11) × 10−3for 231Pa, in disagreement with the theoretical predictions of Feather, but consistent with the semi-empirical systematic of Halpern.

The Punjab is the most populous among the four provinces of Pakistan, which has around 72 million of people and 205 344 km(2) of land. The majority of the population of this province lives in houses made of clay bricks that contain variable amounts of naturally occurring radioactive material (NORM). The concentration level of NORM in clay bricks used to construct dwellings may pose health hazards to inhabitants if it exceeds the permissible limits. For radiological surveillance, activity concentrations of the primordial radionuclides (40)K, (226)Ra and (232)Th were measured in 140 brick samples collected from 35 districts of the Punjab province. A high-purity germanium gamma-ray detector coupled with a personal computer-based multichannel analyzer was employed for the measurement of activity concentrations of primordial radionuclides in the brick samples. The province-wide average activity concentrations and the range (given in parenthesis) of (40)K, (226)Ra and (232)Th were found to be 624 ± 133 (299-918), 35 ± 7 (21-47) and 42 ± 8 (22-58) Bq kg(-1), respectively. The values lie within the range of activity concentration values for clay bricks of some countries of Asia. Potential radiological constraint was checked in the form of hazard indices calculated from the measured activity concentrations; the indices were found to be less than their limiting values. Indoor external dose was calculated for a standard size room made of clay bricks, and the dose rate was 159 ± 30 (83-219) nGy h(-1). The average value of the dose rate is comparable to that of Asian countries and is about twice the worldwide average value. Annual effective dose E(ff) in the bricks-made room was calculated and the average value of the dose was 0.80 mSv y(-1), which is about twice the worldwide background value of 0.41 mSv y(-1).

It is shown that an electron, positron and ion plasma can be self-organized to a double Beltrami state – the superposition of two force-free states. The scale parameters which determine the nature of the self-organized structures are found to depend on the number densities of the plasma species. The loss of equilibrium in slowly evolving double Beltrmi states is investigated. The effects of density ratios, helicities, positron flows and energy on equilibrium are investigated. It is found that the double Beltrami state transforms to a single Beltrami state at the termination of equilibrium. It is also shown that much of the magnetic energy converts to the flow kinetic energy through catastrophic transformation.

Azo dyes are widely used by different industries including the textile industry. A substantial amount of these colorants exist in the water discharged from the textile outlets which contaminate the surrounding water bodies and soil. These colorants could be degraded by bacteria. For this purpose, thirty bacterial strains capable of degrading azo dyes were isolated from textile effluents. Strain IFN4 identified as Shewanella sp. was most efficient in decolorizing RB-5 (200 mg L -1 ) in mineral salt medium and color was removed >90% in just four h. Decolorization efficiency of this stain was also examined using mixture of AR-81, DR-88 and RB-5 dyes and conditions were optimized for their faster degradation. Bacterium degraded the dyes mixture at all pH (5-10) and temperature (20-50°C) values, but with different efficiency. Maximum decolorization of the dyes mixture was recorded at pH 8.5 and at 35°C. Bacterium showed very fast decolorization under static incubation while negligible decolorization occurred under shaking incubation. However, bacterial growth was more under shaking than static culture. Furthermore, 10% (v/v) inoculum concentration was found to be the optimum for decolorization. The decolorization rate of Shewanella sp. strain IFN4 was very high under optimal conditions, which increased its applicability in the treatment of the wastewater. © 2014 Friends Science Publishers

The untreated effluents discharged by different industries, such as metallurgy, fertilizers, pesticide, leather, mining, electroplating, surface finishing, aerospace, and electroplating, have increased the risk of the contamination of bodies of water by heavy metals. Herein, hybrid biosorbent–nanofiltration processes for Pb(II) removal from wastewater was studied. The hybrid biosorbent was prepared from date seed waste and Ganoderma lucidum. Hybrid biosorbent characterization was performed by SEM and FTIR. SEM micrographs showed that the HB surface is irregular. For the adsorption studies, various sorption parameters were optimized. The maximum biosorption capacity of immobilized heat-inactivated hybrid biosorbent was 365.9 mg/g, with the Langmuir isotherm model to present the best fit. Desorption experiments were conducted for regenerating immobilized heat-inactivated hybrid biosorbent for three consecutive cycles using different desorption agents, with acetic acid to be the optimum. Going a step further, nanofiltration was also applied as a post-treatment process to elevate the remediation effectiveness for wastewater of high Pb(II) initial concentrations. The reasonably low cost and high removal of Pb(II) make hybrid biosorbent–nanofiltration processes a prosperous and potentially attractive hybrid approach against heavy-metal-polluted wastewater.

The use of Compton backscattering for the contactless measurement of the thickness of steel sections and similar dense materials up to 25 mm thick, when access is available only from one side of the sample, has been investigated. The expected intensity of back-scattered photons in a Compton thickness gauge has been estimated using a simple model, whose predictions have been verified and extended by the use of the GEANT3 Monte Carlo package which allowed the scattering geometry to be modelled accurately and the effects of multiple scattering to be estimated. The simulations have been confirmed by experimental measurements on steel samples 1 - 45 mm in thickness. With a 5 radioactive source, a rapid, reliable measurement of wall thickness can be obtained with steel samples up to 20 mm thick, but for thicker samples the absorption of backscattered photons limits the accuracy that can be achieved.

The aim of this study is to investigate the impact of the coronavirus pandemic on teenage psychiatry referrals following crisis presentation to the adult emergency department (ED) of an Irish tertiary hospital. In doing so, this study will specifically examine the effect of COVID-19 on self-injurious behaviour, suicidality and substance use among older adolescents (age 16/17 years).This is a retrospective descriptive analysis of acute adolescent psychiatry referrals assessed out-of-hours via the adult ED psychiatry service across three consecutive time points (during the months of March, April and May) from pre-pandemic, 2019 (T1); initial pandemic, 2020 (T2); and peak pandemic, 2021 (T3). Data were obtained via the hospital's ED-specific electronic database, review of original assessment notes and cross-referenced by manually extracting data logged in the on-call register.Crisis psychiatry assessments of teenagers during on-call hours trebled during the period of this study (p < 0.001). Although ED/crisis referrals initially decreased overall at the start of the pandemic, the rate of teenage referrals remained constant, before increasing as restrictions tightened in lockdown. The negative impact of COVID-19 on teenagers' ability to cope was found to be statistically significant (p = 0.001). Changes in rates of self-harming and/or suicidal behaviours were not statistically significant between 2019, 2020 and 2021 (p = 0.082). Alcohol misuse occurred in up to one-third of cases across each timeframe and remained virtually constant throughout the pandemic. Drug misuse decreased from onset of COVID-19 (p = 0.01).To our knowledge, this is the first study to specifically examine the impact of COVID-19 on suicidality, self-harming behaviours, substance misuse and on-call ED presentations of teenagers in Ireland. This study demonstrates that coronavirus-related stress is associated with negative mental health sequelae for vulnerable at-risk older adolescents, as evidenced by a rise in ED presentations and on-call referrals since the onset of the pandemic. Presentation of increased numbers of under-18's for psychiatry assessment at the adult ED/general hospital indicates a deepening chasm between available and aspirational emergency (adolescent-specific) psychiatric care in the community. Mobilising resilience factors and maximising coping skills for at-risk youth will inform tailored intervention and support strategies along with adequate resourcing of services for vulnerable adolescents in the community.

The light-fragment-group mass-energy correlations for 229Th(nth, f), 232U(nth, f) and 239Pu (nth, f) measured with the Cosi fan tutte, have been used to determine the cold fission probability for these fissioning systems. These are the first results on cold fission for 229Th(nth, f) and 232U(nth, f). For 229Th(nth, f) cold fission is realised for the whole mass range ML ≈ 80–99 present in the mass spectrum, but the coldest fission shows up for ML ≈ 85. For 232U(nth, f) cold fission is present for ML ≈ 84–107, with the coldest fission manifesting for ML ≈ 100–105. In the case of 239Pu(nth, f), cold fission exists for ML ≈ 95–112 and here the coldest fission is produced for ML ≈105–110. This systematic study shows that the shells in the nascent fragments seem to play a decisive role in the realisation of cold fission. These results are discussed in terms of the existing concepts and ideas on this phenomenon.

The mass and nuclear charge distributions of fission fragments from229Th(nth, f) have been measured at several kinetic energies with the mass spectrometer Lohengrin (ILL-Grenoble). The average proton e-o effect, which reaches 41%, induces large oscillations in the parameters of the isotopic charge distribution. A comparison of the data from different fissile nuclei shows the importance of the last stage of the process for intrinsic excitations.

A general leptodermous expansion for the density of single-particle levels in thin-skinned potential wells is derived and is used to study the finite size corrections to the macroscopic level density parameters of nuclei. With droplet model values for the potential parameters, the calculated level density parameters for nuclei along the β-stability line show systematic deviations from the experimental estimates. Possible reasons for these deviations are also discussed.

Abstract Fission-fragment mass and kinetic energy distributions and their correlations have been studied for the thermal neutron induced fission of 241 Pu. The global mass distribution is smooth, apart from a small shoulder at μ H ≈ 144 probably due to the deformed shells N ≈ 88 and N ⩾ 60 in the heavy and the light fragment respectively. When low excitation events are selected, these structures become more pronounced. Furthermore, there is a sudden increase of 1–2 MeV in E (μ) for masses around 85 and above 155 which is probably associated with a spherical shell N = 50 in the light fragment. Finally, the prompt neutron emission curve v(m ∗ ) is calculated.

The (nth, α) (nth, p) and (nth, γα) reactions spectroscopical data are reported on 40K and 143Nd. For 40K, values of σα = 0.39 ± 0.08 b, σp = 4.4 ± 0.9 b, σγα = 26 ± 4 mb are obtained and accurate measurements of Eα0 = 3491.7 ± 7 keV and Epo = 2232.9 ± 3 keV have been performed, α1, and p1 transitions and the 40K(nth, γp) reaction have not been observed. The 40K(nth, γα)37Cl and 143Nd(nth, γα)140Ce spectra are presented. The multipolarity of the primary low energy γ-rays is deduced from the γ-α spectra.

The thermal neutron induced (n, α) reaction cross section of 238U was measured using the highly pure thermal neutron beam from the 87 m curved neutron guide at the High Flux Reactor of the ILL (Grenoble). The energy spectrum showed an α-particle line with Eα = 9.05±0.06 MeV and σ(n, α) = 1.3±0.6 μb. The α-particle energy was used to calculate the 235Th mass of 235.04700±0.00008 amu, the Qα value of 9.20±0.06 MeV for the 238U(n, α)235Th reaction and the Qβ value of 1.44±0.08 MeV for the β-decay of 235Th. The cross-section data are compared with the results obtained with the statistical model calculation.

The 235U(nth, α) reaction and the α-particles emitted in the thermal neutron induced fission of 235U were measured using a very pure thermal neutron beam of the Grenoble high flux reactor. An upper limit of 0.66 mb was determined for the 235U(nth, α) reaction cross section, which is lower than all the previous results. The energy distribution of the α-particles produced by the 235U(nth, f) reaction was measured down to 7 MeV with a non-shielded surface-barrier detector telescope assembly. The measured distribution has a quasi-Gaussian shape; it reveals, however, a pronounced deviation from such a shape at lower α-energies. Several possible explanations for this deviation are discussed.

Using a target prepared by on-line isotope separation, thermal neutron capture in 84Rb (Iπ = 2−) has been shown to induce proton emission to the ground state (0+) and first excited state (2+) of 84Kr. The branching ratio was measured as Γp(0+)Γp(2+)= 4.7 ± 0.7, favouring a 32− assignment of the capturing state without excluding 52−, and the (nth, p) cross section as 12 ± 2 b. The energy available for the process was determined to be 3.45 ± 0.01 MeV, in agreement with other mass data in the region.

Abstract The (n, α) reaction has been studied using the highly pure thermal neutron beam from the 87m curved neutron guide at the Grenoble high flux reactor. The 147 Sm(n, α) 144 Nd reaction showed up five lines corresponding to the ground and the first four excited states of the final nucleus. It is shown that ≈53 % of the 581 μb (n, α) cross section comes from the neutron capture by a bound level of the 148 Sm compound nucleus. The 8.7 ± 3 μ b cross section of 151 Eu(n, α) 148 Pm seems to consist principally of at least two lines corresponding to the ground and the second excited states of 148 Pm. The 153 Eu(n, α) 149 Pm cross section for thermal neutrons is ≦ 1 μ b. The lower limits of (n, α) thermal neutron cross section values on ytterbium isotopes are ≈ 20 to 40 times lower than the published data.

Abstract The study of pion-induced nuclear reactions are important because pion not only plays the role of a projectile, but also serves as intermediate step particle as in the case of interaction of other projectiles like photon and antiproton. The studies of pion-induced nuclear reaction have important applications, such as in accelerator-driven system (ADS) and in basic nuclear research to probe the nuclear structure. The studies of pion-induced reaction, particularly fission, are as important as the studies of nucleon-induced nuclear reactions, because inter-nuclear cascades in spallation targets are partly propagated by pions. The pion-induced fission has not been as much studied as fission induced by nucleons. The reason is that there is a limited number of facilities available for production of pions, and beam time is scant. Previously, pion-induced fission has been studied using dielectric track-detectors; at present the work has not been carried out using this technique due to non-availability of exposure facilities. So there is a need of computer codes to study cross-section of pion-induced fission, and the proper documentation of existing experimental data. In the present work, fission cross-sections induced by positive pions, for targets 209Bi, 231Pa, 232Th, 238U and 239Pu are computed using the cascade–exciton model code CEM95 upto 2500 MeV energy. Also a systematics of positive pion-induced fission is performed on the basis of that performed cross-sections of proton-induced fission. The computed cross-sections of fission using CEM95 have been compared with the available experimental data and with the fission cross-sections obtained using the systematics analysis. A reasonable agreement has been observed.

Communication strategy is one of the support of primary health care (PHC) that can address demand-side barriers and socio-cultural factors to promote better services. Conversely, communication strategies have not been a distinct emphasis of vaccination research in the country until now. Therefore, this study aimed to find the elements that influence the provision of vaccination communication in Pakistan. Twenty-two semi-structured interviews with key stakeholders in vaccine communication were conducted using qualitative methodologies (Jan 2022-March 2022). The interviews revolved around factors affecting the implementation of communication. Interviews were transcribed and analyzed using thematic analysis. By using the SURE framework, numerous factors that affect vaccination communication were identified under three major themes such as organizational-level, constitutional, and community-level factors. Five subthemes marked the organizational-level factors such as constrained budget, infrastructure deficits, inconsistent comprehensive strategy, health workforce, and inadequate training. Two subthemes are derived regarding constitutional and community-level factors, respectively, such as governance and leadership, health communication interventions not a policymaker's priority, community perceptions and practices, and formal partnership lacking between national and local stakeholders. Additionally, employment of established communication committees, improved money allocation, engagement of traditional and religious institutions, and political backing were identified as solutions for improvement. Communication activities are an important part of immunization programs in order to increase vaccination coverage. To be able to execute communication interventions more successfully, national and provincial stakeholders must work together to identify the elements that affect vaccine provision. Additional rigorous implementation studies could aid in the development of clearer knowledge of the system-wide constraints obstructing the program's efficiency.

Fission-fragment angular distributions have been measured for the neutron-induced fission of 230Th in the vicinity of the 715 keV resonance with a 2.5 keV (FWHM) neutron energy resolution. An analysis was performed to find a set of fission barrier characteristics that reproduce simultaneously the present angular distribution data and the fission cross-section data of Blons et al. The analysis results show that the data for the 715 keV resonance could be fitted only if allowance is made for the existence of two rotational bands with opposite parities but with the same K quantum number. The moment of inertia parameter kh22I extracted from the analysis has a value of 1.9 keV, which is compatible with the existence of a third minimum in the fission barrier at a quadrupole deformation of ε2 = 0.85.

The far-out asymmetric mass distributions for 235U(nth, f), 239Pu(nth, f), 243Am(nth, f) and 252Cf(sf) have been determined. The structures in these data and those in the existing results on 238U, 234Np and 235Np have been analysed in a systematic way in terms of the static scission-point model of Wilkins et al. The model explains well all the structures seen in very asymmetric fission.

The σ(nth,f) of 243Am has been measured using the cold neutrons with a 25 K Maxwellian distribution available at the Grenoble high flux reactor. Surface barrier detectors recorded the fission fragments. A value of σ(nth,f) = (198.3 ± 4.2)mb was obtained for 243Am relative to σ(nth,f) = (582.2 ± 1.3)b for 235U.

The feasibility of using Ocimum bacilicum seeds for the removal of copper (II) ions from aqueous solution has been investigated. Batch biosorption studies were conducted to study the effect of different experimental parameters such as initial metal ion concentration, contact time, agitation speed, biosorbent dose and pH. The results indicated that sorption equilibrium was established within 30 minutes of contact time. The copper (II) sorption was strictly pH dependent and maximum removal was observed at pH 5. Effective biosorption of copper (II) was taken place at 150 rpm. Maximum biosorption capacity was found to be 73.1 mg/g. The equilibrium data fitted well to the Langmuir isotherm model with R 2 = 0.997. The study revealed that Ocimum bacilicum could be used as biosorbent for the removal of heavy metals ions on large scale.