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DFT investigation of half-metallic ferromagnetic rare earth based spinels mgHo_(2)Z_(4)(Z=S,Se)

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Journal of Rare Earths 2024年第1期42卷 121-128,I0005页

作者： maiza Zanib mumtaz manzoor n.A.noor m.Waqas Iqbal mazia Asghar H.H.Hegazy A.Laref Department of Physics Riphah International UniversityLahore CampusPakistan Research Centre for Advanced materials Science King Khalid UniversityP.O.Box 9004AbhaSaudi Arabia Department of Physics Faculty of ScienceKing Khalid UniversityP.O.Box 9004AbhaSaudi Arabia Department of Physics and Astronomy College of ScienceKing Saud UniversityRiyadh11451Saudi Arabia

Half-metallic ferromagnetism,mechan.cal as well as thermoelectric properties for rare earth-based spinels mgHo_(2)Z_(4)(Z=S,Se)were investigated using density functional theory(DFT).Structural optimization was done with Perdew-Burke-Ehrenzorf(PBE)sol-generalized gradient approximation(GGA)to calculate the lattice constant of both spinels comparable to experimental *** addition,Born stability criteria and negative formation energy show that our studied spinels are also structurally and dynamically stable in the cubic *** ferromagnetic(Fm)state stability,we also calculated the energy differences among Fm,antiferromagnetic(AFm),and non-magnetic(nm)***,Curie temperatures of ferromagnetic phases were also *** used Trans-Blaha improved BeckeJohnson(TB-mBJ)potential functional for electronics as well as magnetic characteristics,which lead to the consistent explanation of half-metallic ferromagnetism,representing the whole band-occupancy in material with exact detail of density of states(DOS).The stable Fm state was examined in spinels due to the exchange splitting of Ho cation consisting of p-d hybridizations compatible with the result achieved for electronics band structure and ***,spin magnetic moment was explained in terms of anion.cation,and sharing charge on studied *** addition,the calculated thermoelectric properties clearly show that operation range of these systems may be utilized by future experimental works for identifying the potential applications of these systems.

关键词： Ho-based spinels DFT simulations mechan.cal parameters Electronic properties Hm ferromagnetism Figure of merit

Compression properties of cost-efficient porous expanded clay reinforced AA7075 syntactic foams fabricated by industrial-oriented die casting technology

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China Foundry 2024年第1期21卷 60-70页

作者： İsmail Cem Akgün Çağın Bolat Ali Gökşenli Faculty of mechan.cal Engineering Istanbul Technical University34437İstanbulTurkey Faculty of Engineering Samsun University55420SamsunTurkey

In today’s manufacturing industries,hard competition between rival firms makes it compulsory for researchers to design lighter and cheaper machine components due to the megatrends of cost-effectiveness and *** this point,aluminum syntactic foams(ASFs)are new-generation engineering composites and come into the upfront as a *** to their features like low density,sufficient elongation,and perfect energy absorption ability,these advanced foams have been considerably seductive for many industrial sectors *** this study,an industrial-oriented automatic die casting technology was used for the first time to manufacture the combination of AA7075/porous expanded clay(PEC).micro evaluations(optical and FESEm)reveal that there is a homogenous particle distribution in the foam samples,and inspections are compatible with the other ASF ***,T6 aging heat treatment was operated on one half of the produced foams to explore the probable impact of aging on the compressive *** results show that PEC particles can be an alternative to expensive hollow spheres used in the previous ***,a favorable relationship is ascertained between the aging treatment and mechan.cal properties such as compression strength and plateau strength.

关键词： die casting porous materials metal matrix sytanctic foams expanded clay compressive deformation

Towards defining soil quality of mediterranean.calcareous agricultural soils:Reference values and potential core indicator set

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International Soil and Water Conservation Research 2024年第1期12卷 145-155页

作者： Germán A.Durán Daniel Sacristán Edelweis Farrús Jaume Vadell Institut de Recerca i FormacióAgrària i Pesquera de les Illes Balears C/Eusebi Estada14507009PalmaSpain Plant Biology Department University of Valencia46100BurjassotValenciaSpain Soil and Environmental Quality Department Centro de Investigaciones sobre Desertificación-CIDE(CSIC-Universitat de València-Generalitat Valenciana)Carretera Moncada-Náquera km 4.546113MoncadaValenciaSpain Universitat de les Illes Balears Cra.De Valldemossakm 7507122PalmaSpain

To avoid soil degradation,adapt to climate change and comply with the Sustainable Development goals 2030(Un General Assembly),establishing the quality/fertility of the agricultural soils of the mediterranean region and evaluate how these evolve with time is *** enables adequate management practices to be *** mediterranean.calcareous region has received little attention in this sense,in spite its soil ***,24 different representative calcareous agricultural soils of the mediterranean region,including the main management strategies of agricultural soils(rainfed and irrigated),were sampled from the island of mallorca;and their physical,chemical and biological properties *** values obtained for most of the soil characteristics allowed to establish an initial approach to the reference values for the type of calcareous agricultural soils considered,and to clearly distinguish the effect of rainfed or irrigation management practices on soils properties and *** enzyme activities were not stimulated by the irrigation conditions assayed or they were only in dry conditions,suggesting optimum enzyme activities could be obtained when alternating dry and humid soil *** organic carbon.calcium carbonate and active lime revealed of significant importance in the collection of ***,the results obtained clearly indicate the heterogeneity of the region and its implications on the different soil ***,this study could serve as a starting point to adequately establish the quality(fertility)for mediterranean.calcareous agricultural soils and their reference values by conducting further research in this region and including more type of soils.

关键词： Soil fertility mediterranean agricultural soils calcareous soils Soil enzymes Soil management

Cr-induced fusion reactions to synthesize superheavy elements

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nuclear Science and Techniques 2024年第5期35卷 122-130页

作者： S.madhu H.C.manjunatha n.Sowmya B.m.Rajesh L.Seenappa R.S.Susheela Department of Physics R V College of EngineeringBangalore 560074India Visvesvaraya Technological University BelagaviKarnataka 590018India Department of Physics Government First Grade CollegeSrinivasapurKarnataka 563135India Department of Physics Government First Grade CollegeDevanahallyKarnataka 562110India Department of Physics Government First Grade CollegeMulbagalKarnataka 563131India Department of Physics Government First Grade collegeNanjangudOoty RoadMysore 571301India

We investigated ^(50,52-54)Cr-induced fusion reactions for the synthesis of the superheavy element in the 104≤Z≤122 *** cross sections produced in this investigation using ^(54)Cr projectiles were compared with those obtained in prior *** estimated cross sections from this analysis are consistent with the findings of prior *** the current study,the predicted cross section was found to be 42fb at 236 meV for ^(53)Cr+^(243)Am,23.2 fb at 236 meV for ^(54)Cr+^(247)Cm,95.6 fb at 240 meV for ^(53)Cr+248Bk,and 1.33 fb at 242 meV for ^(53)Cr+***,these projected cross sections with excitation energy and beam energy will be useful in future Cr-induced fusion reaction investigations.

关键词： Fusion cross sections Compound nucleus formation probability Survival probability Evaporation residue cross sections

Weather influenced nestling growth of an insectivorous but not a granivorous grassland passerine in Argentina

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Avian Research 2024年第2期15卷 156-162页

作者： martín Alejandro Colombo Adrian Jauregui Luciano n.Segura Laboratorio de Ecología de Aves.Institute“Dr.Raúl A.Ringuelet”(ILPLA)-UnLP/COnICET Boulevard 1201437La PlataB1900Buenos AiresArgentina

nestling growth of birds can be affected by weather *** general,it is expected that higher temper-atures favor growth by improving food availability and nestling metabolism,while rain hinders it by reducing foraging ***,most of these patterns have been described in insectivorous cavity-nesting birds in temperate *** tested these predictions in two neotropical grassland ground-nesting birds with contrasting nestling diets and therefore potentially different responses to *** measured nestlings of the Hellmayr’s Pipit(Anthus hellmayri,an insectivorous passerine)and the Grassland Yellow-Finch(Sicalis luteola,which feeds its nestlings exclusively with seeds)during three breeding seasons(2017-2020)in central-eastern *** took measurements of tarsus and body mass,modeled growth curves using nonlinear mixed-effects models,and evaluated the effects of minimum daily temperature and precipitation during the growth period and the 30 days prior to *** pipits(60 nestlings from 21 nests),minimum temperatures during the growth period were positively associated with tarsus and body mass ***,there was a positive association between precipitation during the pre-hatching period and tarsus ***,none of the weather variables analyzed had significant effects on nestling growth of finches(131 nestlings from 35 nests).Dietary contrast between species may explain the different *** activity and abundance can be affected by weather variations within the span of a breeding season,whereas seeds may depend on conditions from previous years,making the effects harder to *** with reduced asymptotic size can have reduced chances of ***,pipit populations could be impacted if they experience cold and dry conditions during their breeding season,which is of major relevance in the current context of climate change.

关键词： Finches Grassland birds neotropical birds Pipits Precipitation Temperature

First-principles calculations to investigate structural,electronic,magnetic,optical and thermodynamic properties of RE_(2)Rh_(3)Ge(RE=Pr,Sm)

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Journal of Rare Earths 2024年第7期42卷 1385-1393,I0007页

作者： A.Ezaier R.masrour m.Hamedoun J.Kharbach A.Rezzouk A.Hourmatallah n.Benzakour K.Bouslykhane Laboratory of Solid Physics Faculty of Sciences Dhar El MehrazSidi Mohamed Ben Abdellah UniversityBP 1796FezMorocco Equipe de Physique du Solide LaboratoiresLIPIEcole Normale SupérieureBensoudaFèsMorocco

In this paper,we analyzed the physical characteristics of the ternary alloys RE_(2)Rh_(3)Ge(RE=Pr and Sm)using the first principles calculation based on functional density theory integrated in the Wien2k *** calculated formation energies of Pr_(2)Rh_(3)Ge and Sm_(2)Rh_(3)Ge are−5.3827 and−5.2782 eV/atom,respectively,showing that these alloys may exist *** results of the band structure and density of states indicate that all of the compounds tested are magnetic metals,and their magnetism is mostly related to the contribution of Pr and Sm *** total magnetic moments of Pr_(2)Rh_(3)Ge and Sm_(2)Rh_(3)Ge are 4.07245 and 11.16161μB/f.u,*** parameters such as heat capacity at constant pressure,entropy,Debye temperature,lattice volume,compressibility coefficients,and Grüneisen parameter alloys were calculated using the Gibbs algorithm and studied in depth over a large temperature range of 0-900 *** Debye temperature increases with increasing pressure and decreases with decreasing ***,the Debye temperatures calculated at p=0 GPa and T=300 K are equal to be 342 and 322 K for Pr_(2)Rh_(3)Ge and Sm_(2)Rh_(3)Ge,*** optical characteristics such as the real and imaginary portions of the dielectric function,the absorption coefficient,the energy-loss function,and the refractive index were investigated and discussed in more depth.

关键词： magnetic metals Functional density theory Density of states magnetic moment Optical and thermodynamic properties Rare earths

Epidemiology of work-related hand and wrist injuries in a referral center: A descriptive study

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World Journal of Orthopedics 2024年第7期15卷 650-659页

作者： Angélica m Rodríguez Ginna P Tocanchón Jessica T Villalba Luis m Pombo Aníbal A Teherán Gabriel camero-Ramos Karen P Ayala Gerhard m Acero Research Center Fundación Universitaria Juan N.CorpasBogotá111321Colombia Red Cross Cruz Roja Colombiana-Seccional Cundinamarca BogotáBogotá111221Colombia Vigilancia Epidemiológica Instituto Nacional de SaludBogotá111321Colombia

BACKGROUnD Occupational hand and wrist injuries(OHWIs)account for 25%of work-related accidents in low-and middle-income *** Colombia,more than 500000 occupational accidents occurred in 2021,and although the rate declined to less than 5%in 2020 and 2021,at least one in four accidents involved a hand or wrist *** To describe the OHWIs in workers seen at the emergency room at a second-level hospital in *** An observational study was performed using data from workers who experienced OHWIs and attended a second-level hospital,between June,2020 and may,*** overall frequency of OHWIs,as well as their distribution by sociodemo-graphic,clin.cal,and occupational variables,are ***,association patterns between sex,anatomical area(fingers,hand,wrist),and type of job were analyzed by correspondence analysis(ca).RESULTS There were 2.101 workers treated for occupational accidents,423(20.3%)were cases of OHWIs,which mainly affected men(93.9%)with a median age of 31 years and who worked mainly in mining(75.9%).OHWIs were more common in the right upper extremity(55.3%)and comprised different types of injuries,such as contusion(42.1%),laceration(27.9%),fracture(18.7%),and crush injury(15.6%).They primarily affected the phalanges(95.2%),especially those of the first finger(25.7%).The cas showed associations between the injured anatomical area and the worker’s job that differed in men and women(explained variance>90%).COnCLUSIOn One out of five workers who suffered occupational accidents in Cundinamarca,Columbia had an OHWI,affecting mainly males employed in *** occupational profile is likely to lead to prolonged rehabilitation,and permanent functional *** results might be useful for adjusting preventive measures in cluster risk groups.

关键词： Accidents Occupational Epidemiology Hand injuries Wrist injuries Occupational health

Habitat and food preferences of European rabbits in core and edge populations along the invasion front Patagoniamonte,Argentina

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Current Zoology 2024年第3期70卷 310-319页

作者： Sabrina Yasmin Bobadilla maría A.Dacar Fabián m.Jaksic Ricardo A.Ojeda maría Fernanda Cuevas Ecología de mamíferos de Tierras Secas IADIZACCT-Mendoza CONICETAv.Ruiz Leal s/nParque General San MartínMendoza 5500MendozaArgentina Laboratorio de Filogeografía Taxonomía Integrativa y Ecología(LFTIE)IADIZACCT-Mendoza CONICETAv.Ruiz Leal s/nParque General San MartínMendoza 5500MendozaArgentina Center of Applied Ecology and Sustainability(caPES) Pontifcia Universidad Católica de ChileAv.Libertador Bernardo O'Higgins 340Santiago 8320000Región MetropolitanaChile

The European rabbit Oryctolagus cuniculus is an exotic herbivorous mammal undergoing an active phase of geographical expansion in the arid ecosystems of *** Adaptive Flexibility Hypothesis states that populations at the range edge(new populations)will exhibit greater fexibility in the use of resources compared with populations located in the range core(older populations).The objective of this work was to compare the rabbit’s use of spatial and trophic resources in relation to the establishment time of their *** sampling was carried out for 2 years(2017 and 2018)in sites with different establishment times for rabbit *** sampling stratifed by type of habitat was applied using 115 fxed strip transects of 1,000 m^(2) laid out across the study *** rabbit signs were recorded in each transect,and environmental and anthropic variables were *** results show that the individuals from the range edge are more selective in the use of habitat than those from the range *** the microhabitat level,we observed a pattern in the particular components of habitat use by rabbits mainly linked to food availability and proximity to *** a trophic perspective,rabbits could show fexible adjustment to novel conditions and environments in the range *** variability in resource use by the European rabbit confrms its ecological fexibility,pivotal for their advance toward new environments in Argentina.

关键词： Arid ecosystems invasive species novel environments range invasion spatial use trophic use

The effectiveness of different wear indicators in quantifying wear on railway wheels of freight wagons

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Railway Engineering Science 2024年第3期32卷 307-323页

作者： Philipe Augusto de Paula Pacheco m.magelli matheus Valente Lopes Pedro Henrique Alves Correa n.Zampieri n.Bosso Auteliano Antunes dos Santos Federal Institute of the Southeast of minas Gerais(IF Sudeste mG) Técnico PanamáStreet 45Santos DumontMG 36246-311Brazil Railway Laboratory(Lafer) Universidade Estadual de Campinas(UNICAMP)Mendeleyev Street 200CampinasSP 13083-872Brazil Department of mechan.cal and Aerospace Engineering Politecnico Di TorinoC.so Duca degli Abruzzi 2410129 TurinItaly

Railway infrastructure relies on the dynamic interaction between wheels and rails;thus,assessing wheel wear is a critical aspect of maintenance and *** paper focuses on the wheel-rail wear indicator T-gamma(Tγ).Amidst its use,it becomes apparent that Tγ,while valuable,fails to provide a comprehensive reflection of the actual material removal and actual contact format,which means that using only Tγas a target for optimization of profiles is not *** this work,three different freight wagons are evaluated:a meter-gauge and a broad-gauge heavy haul vehicles from South American railways,and a standard-gauge freight vehicle operated in Europe,with different axle loads and dissimilar new wheel/rail *** vehicles are subjected to comprehensive multibody simulations on various *** simulations aimed to elucidate the intricate relationship between different wear indicators:Tγ,wear index,material removal,and maximum wear depth,under diverse curves,non-compensated lateral accelerations(A_(nc)),and *** findings showed a correlation of 0.96 between Tγand wear depth and 0.82 between wear index and material removed for the outer *** the results,the Tγis better than the wear index to be used when analyzing wear depth while the wear index is more suited to foresee the material *** results also show the low influence of A_(nc)on wear index and Tγ.By considering these factors together,the study aims to improve the understanding of wheel-rail wear by selecting the best wear analysis approaches based on the effectiveness of each parameter.

关键词： Wear index Wear volume Wear modeling Dynamic simulation