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Statistical uniformity of discharge variation is an important parameter in designing drip irrigation laterals. A simple analytical equation is derived to determine the coefficient of variation of discharge. This equation is used to determine the coefficient of variation of discharge for a numerical problem. The result is compared with the energy gradient line approach. Both the methods give the same result. For any required coefficient of variation of discharge, the diameter of a lateral can be designed directly for a known lateral length, slope, emitter discharge exponent, pressure head at the start of the lateral, and discharge rate through the lateral, by writing the analytical equation in quadratic form. CE Database subject headings: Trickle irrigation; Uniformity; Laterals; Water discharge.

Interlayer exchange coupling was investigated in highly Co-enriched (75.6 at. %), i.e., in Co antisite defective Heusler alloy Co-Mn-Si-based epitaxial trilayer structures for a wide range of spacer Cr thicknesses (tCr). The exchange coupling parameters J1 (bilinear coupling) and J2 (90° coupling) were estimated from the comparison of experimental and numerical simulations of M-H loops. The comparable contributions of both the bilinear and 90° couplings were observed in a spacer thickness range, tCr ∼ 0.3 to 4.2 nm. The relative angle of magnetization at remanence between the bottom and top Co-Mn-Si layers was found to vary from 67° to a maximum of 152° as a result of competition between bilinear and 90° couplings. In contrast to the observation of strong 90° coupling without any detectable bilinear type 180° coupling in almost stoichiometric and chemically B2-ordered Co2MnSi-based trilayer structures in a previous study, the results in this study clearly indicated the importance of the effect of chemical ordering on dominating 90° coupling in Heusler alloy-based structures. [ABSTRACT FROM AUTHOR]

The space layer thickness dependence of interlayer exchange coupling is examined in the fully epitaxial trilayers of the [Co.sub.2]MnAl (CMA)/Cr/CMA structure. The comparison of the results of the experiments and the simulations of magnetization curves have disclosed novel behavior, dominating the 90[degree] coupling and the absence of 180[degree] coupling.

The spacer layer thickness dependence of interlayer exchange coupling has been investigated in the fully epitaxial trilayers of the Co2MnAl (CMA)/Cr/CMA structure. A series of high-quality samples of CMA (20 nm)/Cr (tCr=0.3–8.1 nm)/CMA (10 nm) trilayers was prepared on a MgO substrate by ultrahigh vacuum compatible dc sputtering. Comparison of the results of the experiments and the simulations of magnetization curves revealed novel behavior, dominating the 90° coupling and the absence of 180° coupling. No clear oscillation, only a peak of the 90° coupling strength (J2∼-0.68 erg/cm2), was observed at tCr=1.2 nm. [ABSTRACT FROM AUTHOR]

We study spin torque oscillators comprised of a perpendicular spin injection layer (SIL) and a planar field generating layer to reveal the influence of the spin polarization of SIL material on the critical current density, JC, to induce microwave oscillation. Two systems with different SIL are compared: one with a highly spin-polarized Heusler alloy, Co2Fe(Ga0.5Ge0.5) (CFGG), and the other a prototypical Fe2Co alloy. Cross sectional scanning transmission electron microscopy observations show the B2-ordered structure in a 3-nm-thick CFGG SIL, a prerequisite for obtaining half-metallic transport properties. Current induced microwave oscillations are found at frequencies of ~15 GHz for both systems. However, the current needed to cause the oscillations is ~50% smaller for films with the CFGG SIL compared to those of the Fe2Co SIL. These results are in accordance with micromagnetic simulations that include spin accumulation at the SIL. [ABSTRACT FROM AUTHOR]

We report enhancement of L2 1 order and the resultant improvement of spin polarization of Co 2 MnSi (CMS) Heusler alloy thin films by a small amount of Ag alloying ( x Ag ⩽ 4.5 atomic (at.) %). The degree of L2 1 order in CMS increases with x Ag (=2.7 at.% and 4.5 at.%), which shows a positive correlation with the magnitude of negative anisotropic magnetoresistance ratio, suggesting the enhancement of spin polarization. Since the benefit of Ag-doping was confirmed even at low annealing temperature around 350 °C, this method could be useful for processing spintronic devices using Heusler alloys at relatively low annealing or substrate temperature. [ABSTRACT FROM AUTHOR]

The recently discovered spin Seebeck effect (SSE) which generates spin voltage due to a temperature gradient in ferromagnets, was systematically studied in half-metallic Heusler compound Co2MnSi (CMS)/Pt thin films to investigate the effect of spin polarization of ferromagnetic layer on SSE. An epitaxial thin film of CMS with an almost perfect B2-ordered structure was prepared directly on a MgO(001) substrate. The measurement was performed at room temperature for various temperature differences, ΔT = 0-20 K between higher (300 K+ΔT) and lower (300 K) temperature ends along the film. The clear sign reversal of the thermally induced spin voltage due to SSE at the higher and lower temperature ends of the CMS film was detected by means of inverse spin-Hall effect in a Pt wire. The SSE was also investigated in a Py thin film deposited on a MgO(001) substrate and compared to that with CMS to verify the effect of spin polarization on SSE. Comparable signals of SSE in CMS and Py thin films suggested that thermal excitation of magnons might have more vital effects in SSE than the degree of spin polarization in ferromagnetic metals. [ABSTRACT FROM AUTHOR]

Magnetic properties of thin Co50Fe50 films on MgO(0 0 1) prepared with different annealing temperatures between room temperature and 300 °C are studied by vectorial magnetometry based on the magnetooptic Kerr effect. Independent from the annealing, the Co50Fe50 films reveal some similar magnetic properties, e.g. no quadratic magnetooptic Kerr effect and a magnetic reversal process which is completely in-plane with magnetic easy axes in Co50Fe50〈1 1 0〉 directions. If the alignment of the external magnetic field is close to the magnetic hard axes, incoherent rotation of magnetic moments between saturation and remanence occurs instead of coherent rotation as for the other directions. If the magnitude of the magnetization is polar plotted with respect to the azimuthal magnetization angle, sequential switching of magnetic moments from one magnetic easy axis to another can be proved by the course of the magnetization. Here, a two-domain switching process can be distinguished from a four-domain switching process generated by the incoherent rotation between saturation and remanence. Furthermore, both the uniaxial magnetic anisotropy constants and the domain wall pinning energies are determined from the magnetic switching fields using the Stoner–Wohlfarth model while the cubic magnetic anisotropy constants are obtained from fitting the magnetization curves. The domain wall pinning energies obtained from these analyses decrease with increasing annealing temperature due to fewer defects in the film. The cubic magnetic anisotropy also decreases slightly which can be attributed to relaxation of the crystal lattice for increasing annealing temperature due to a small change of spin–orbit coupling. Compared with the cubic magnetic anisotropy the uniaxial magnetic anisotropy is very small. This may be attributed to the reduction of strain in the film caused by a buffer stack Cr/Au/Cr between the Co50Fe50 film and MgO(0 0 1). [ABSTRACT FROM AUTHOR]

The magnetic structure of a thin B2 ordered Co50Fe50 film is determined by vectorial magnetometry using magnetooptic Kerr effect including different polarizations of the incident light and varied directions of the external magnetic field. Both the magnetic reversal process and the magnetic remanence reveal two in-plane magnetic easy axes of different strengths which are not orthogonal. Atypical magnetization curves including multidomain states in magnetic remanence with some magnetic moments providing antiparallel alignment to the direction of the previously applied external field (if projected to the direction of the external field) confirm the appearance of different strong magnetic easy axes. This magnetic structure can be explained by a cubic magnetic anisotropy (CMA) induced by the crystalline film structure superimposed by an additional uniaxial magnetic anisotropy (UMA) which is not parallel to one of the magnetic easy axes of the CMA. The results are compared with the regular magnetic behaviour of a thin A2 ordered Co50Fe50 film with UMA parallel to one of the magnetic easy axes of the CMA. [ABSTRACT FROM AUTHOR]

Abstract: The aim of this paper is the comparative study of WIMS library group constants generated from ENDF/B-VI and JENDL-3.3 evaluated nuclear data files. The WIMSLIB group constants have been generated from ENDF/B-VI and JENDL-3.3 through NJOY''99 for 20Ca, 12Mg, 15P, 16S, 14Si, 22Ti, and 23V. The GROUPR output was processed by WIMSR to produce the WIMSLIB group constants. The parameters compared are slowing down power/lethargy widths, transport cross-section, absorption cross-section and Goldstein–Cohen λ parameters. WIMS library generated from ENDF/B-VI and JENDL-3.3 have good agreement in general but some significant points of disagreement also exist. These observations can be used as inputs for the WIMS update library of TRIGA Mark-II research reactor and also for the ENDF/B-VI and JENDL-3.3 data verification tasks. [Copyright &y& Elsevier]

Chlorpyrifos (CPF) is a highly toxic phosphate-rich organic pesticide (OP), identified as an emerging contaminant and used extensively in agricultural production. CPF persistence in the environment and its potential health hazards has become increasingly concerning worldwide in recent years due to exponential rise in food demand. Biodegradation of chlorpyrifos by microbial cultures is a promising approach to reclaiming contaminated soil and aquatic environments. The purpose of this review is to summarize the current understanding of microbiological aspects of xenobiotic chlorpyrifos biodegradation, including microbial diversity, metabolic pathways, and factors that modulate it. In both aerobic and anaerobic environments, CPF is biochemically broken down by a broad spectrum of bacteria and fungi. Hydrolysis, dehalogenation, and oxidation of chlorpyrifos are all enzymatic reactions that lead to its degradation. Biodegradation rate and efficiency are strongly influenced by parametric variables such as co-substrates abundance, pH, temperature, and initial chlorpyrifos concentration. The review provides evidence that microbial biodegradation is a viable method for remediating chlorpyrifos-contaminated sites in a sustainable and safe manner., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Dye wastewater possess immense toxicity with carcinogenic properties and they persist in environment owing to their stability and resistance to chemical and photochemical changes. The bio degradability of dye-contaminated wastewater is low due to its complex molecular structure. Nano-photocatalysts based on zinc oxide are reported as one of the effective metal oxides for dye remediation due to their photostability, enhanced UV and visible absorption capabilities in an affordable manner. An electron-hole pair forms when electrons in the valence band of ZnO nano-photocatalyst transfer into the conduction band by absorbing UV light. The review article presents a detailed review on ZnO applications for treating acidic and basic dyes along with the dye degradation performance based on operating conditions and photocatalytic kinetic models. Several acidic and basic dyes have been shown to degrade efficiently using ZnO and its nanocomposites. Higher removal percentages for crystal violet was reported at pH 12 by ZnO/Graphene oxide catalyst under 400 nm UV light, whereas acidic dye Rhodamine B at a pH of 5.8 was degraded to 100% by pristine ZnO. The mechanism of action of ZnO nanocatalysts in degrading the dye contamination are reported and the research gaps to make these agents in environmental remediation on real time operations are discussed., (© 2024. The Author(s), under exclusive licence to Springer Nature B.V.)

The contamination of aqueous environment by phenol poses a major threat due to its hyper toxic effects and removal of phenol is challenging due to its hydrophilic properties. This research study examines the surface encapsulation of iron oxide (IO) with bio-derived carbon-based date palm (DP) to make date palm-iron oxide (DP-IO) nanocomposite to potentially remediate phenol in aqueous environment. Phenol removal percentage is predominantly influenced by environmental factors, namely pH, nano sorbent loading, temperature, agitation speed, and initial phenol concentration. Under optimum conditions of 30 °C and pH 7.8, 80.30% of phenol was removed using a 0.75 g/L sorbent load with 100 mg/L initial phenol concentration. Langmuir isotherm fitted well (R2 > 0.997), supporting single-layer phenol attachment with maximum bio-sorption capacity of 72.46 mg/g. A pseudo-2nd-order (PSO) kinetic model is identified to be the most appropriate for the DP-IO sorption experiment (R2>0.999). Scanning electron microscopic images, X-ray diffraction observations, FT-IR plots, and thermogravimetric analysis have been used to characterize. The removal mechanism involves unimolecular layer and chemisorption is identified as a rate determining step. The reuse potential proved that the synthesized nanocomposite as a sustainable solution for phenolic wastewater treatment., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Inc. All rights reserved.)

The rapid consumption of metals and unorganized disposal have led to unprecedented increases in heavy metal ion concentrations in the ecosystem, which disrupts environmental homeostasis and results in agricultural biodiversity loss. Mitigation and remediation plans for heavy metal pollution are largely dependent on the discovery of cost-effective, biocompatible, specific, and robust detectors because conventional methods involve sophisticated electronics and sample preparation procedures. Carbon dots (CDs) have gained significant importance in sensing applications related to environmental sustainability. Fluorescence sensor applications have been enhanced by their distinctive spectral properties and the potential for developing efficient photonic devices. With the recent development of biomass-functionalized carbon dots, a wide spectrum of multivalent and bivalent transition metal ions responsible for water quality degradation can be detected with high efficiency and minimal toxicity. This review explores the various methods of manufacturing carbon dots and the biochemical mechanisms involved in metal detection using green carbon dots for sensing applications involving Cu (II), Fe (III), Hg (II), and Cr (VI) ions in aqueous systems. A detailed discussion of practical challenges and future recommendations is presented to identify feasible design routes., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

SARS-CoV-2 has been highly susceptible to mutations since its emergence in Wuhan, China, and its subsequent propagation due to containing an RNA as its genome. The emergence of variants with improved transmissibility still poses a grave threat to global health. The spike protein mutation is mainly responsible for higher transmissibility and risk severity. This study retrieved SARS-CoV-2 variants structural and nonstructural proteins (NSPs) sequences from several geographic locations, including Africa, Asia, Europe, Oceania, and North and South America. First, multiple sequence alignments with BioEdit and protein homology modeling were performed using the SWISS Model. Then the structure visualization and structural analysis were performed by superimposing against the Wuhan sequence by Pymol to retrieve the RMSD values. Sequence alignment revealed familiar, uncommon regional among variants and, interestingly, a few unique mutations in Beta, Delta, and Omicron. Structural analysis of such unique mutations revealed that they caused structural deviations in Beta, Delta, and Omicron spike proteins. In addition, these variants were more severe in terms of hospitalization, sickness, and higher mortality, which have a substantial relationship with the structural deviations because of those unique mutations. Such evidence provides insight into the SARS-CoV-2 spike protein vulnerability toward mutation and their structural and functional deviations, particularly in Beta, Delta, and Omicron, which might be the cause of their broader coverage. This knowledge can help us with regional vaccine strain selection, virus pathogenicity testing, diagnosis, and treatment with more specific vaccines., Competing Interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (© The Author(s) 2023.)

Selenium is targeted as a priority pollutant to be removed due to its high toxicity level and lethal effects. In this research, a novel nano sorbent was fabricated using ionic liquid on multiwalled carbon nanotubes (IL-MCNT) and employed for Selenium remediation from aqueous media. Besides solution pH, nanocomposite dosage, the initial selenium concentration, temperature and sorption time were also examined as operating variables. At optimal pH 2.0, 96% of the selenium was removed with maximum efficiency with 100 mg/L of IL-MCNT at 308 K, 45 min of contact time, and 110 g of IL-MCNT dosage. From kinetic studies, it appears that the Langmuir isotherm fits the observed data (R2 > 0.9813), supporting the hypothesis that monolayer attachment occurs. The Langmuir isotherm parameters are evaluated as qm = 125 mg/g and KL = 0.172 L/mg. As a result of testing several kinetic models, the pseudo-second-order model was the most suitable for experimental data (R2 > 0.9746). Scanning Electron Microscopy images, FTIR spectra, and thermogravimetric study were used to examine the synthesized nanomaterial., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Lead and Cadmium, identified as toxic heavy metals, cause significant imbalance in the eco-system due to their tendency to bioaccumulate. Remediation of heavy metals by conventional adsorptive materials suffer demerits related to low efficiency or removal. Among the variety of adsorbent materials used in the adsorption process, metal oxides- and graphene oxide magnetic nanocomposites have gained a considerable attention. The use of nanomaterials may help to reduce this contamination, but after use, they are difficult to remove from water. An added magnetic property to nanomaterials facilitates their retrieval after use. The magnetic properties of these hybrid magnetic nanocomposites, coupled with unique characteristics of organic and inorganic elements, have found extensive application in water treatment technology. Detailed discussion on functionalisation of magnetic nanocomposites and the enhanced performance are presented. Magnetic graphene oxide-covalently functionalized-tryptophan was reported to have the highest adsorption capacity of 766.1 mg/g for remediation of lead (II) ions and graphene oxide exhibited the highest adsorption capacity of 530 mg/g for Cd (II) ions. The adsorption mechanisms for heavy metal ions on the surface of novel adsorbents, particularly lead and cadmium, using magnetic nanocomposites have been explained with reference to the isotherm models studied. The future scope of research in this area of research is proposed., (Copyright © 2022 Elsevier Inc. All rights reserved.)