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Journal of Rare earths 2019年第10期37卷 1096-1101页

作者： M.Gjoka C.Sarafidis G.Giannopoulos D.Niarchos G.Hadjipanayis J.A.Tabares G.A.Pérez Alcázar l.e.zamora Institute of Nanoscience and Nanotechnology NCSR Demokritos15310AthensGreece Department of Physics and Astronomy University of DelawareNewarkDEUSA Department of Physics Aristotle University of Thessaloniki54124ThessalonikiGreece Departamento de Física Universidad del ValleA.A.25360CaliColombia

This study reports the stabilization of the RFe12-type based compounds where part of R and Fe are substituted with Zr and Co and Si, respectively, in order to examine whether these rare-earth-lean materials are suitable for applications as permanent magnets. Structural and magnetic characterization of the family of alloys with the general formula Nd0.4 Zr0.6 Fe10-xCoxSi2(x = 0 -3) and their melt-spun ribbons were carried out using X-ray diffraction and M€ossbauer spectroscopy. The ThMn12-type structure is obtained for all samples as the majority phase with a minority a-Fe(CoSi) phase(less than 5 wt%) as it was estimated by XRD for x = 1 and 2. The Curie temperature increases linearly with Co substitution from 561 K for x = 0 to 712 K for x = 3. The saturation magnetization decreases slightly from 130.5(x =1)to 129.1 A·m2/kg(x=3), while the anisotropy field is following the same trend.

关键词： Permanent magnets X-ray diffraction M€ossbauer spectroscopy Rare-earth-lean magnetic materials Magnetic properties Melt-spun ribbons

Systematic study of the dependence of magnetic and structural properties of Nd2Fe14B powders on the average particle size

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Journal of Rare earths 2020年第9期38卷 961-968,I0002页

作者： J.F.Durán Perdomo G.A.Pérez Alcázar H.D.Colorado J.A.Tabares l.e.zamora J.J.S.Garitaonandia Department of Physics University of ValleA.A.25360 CaliColombia Applied Physics II Department Basque Country University48080 BilbaoSpain

A systematic study of the magnetic and structural properties dependence on the particle size was *** this,commercial NdFeB powder was separated into five different mean particle sizes using ***,from the original powder,eleven samples were also produced by mechanical milling assisted by surfactant,using various milling times.A total of sixteen samples were studied by scanning electron microscopy(SeM),X-ray diffraction(XRD),vibrating sample magnetometry(VSM),and Mdssbauer spectrometry(MS).The particle sizes of the samples vary from the micrometer to the nanometer *** crystallite size decreases with decreasing particle *** result indicates that the Nd2Fe14B phase is found in all the samples,and the presence of this phase is also corroborated by MS using six sextets for fitting their spectra,with an additional singlet corresponding to the Nd1.1Fe4B4 *** mean hyperfine magnetic field increases with increasing particle size because the magnetic dipolar interaction between the magnetic moment of the particles increases with particle *** the VSM measurements the magnetic energy density(BH)max values were calculated for different particle sizes,and their maximum value of 34.45 MGOe is obtained for the sample with the particle size of 60μm.

关键词： Hard magnetic material XRD Mossbauer spectrometry Magnetization Particle size Rare earths

expression changes of mi RNA-regulated genes associated with the formation of the leafy head in cabbage

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Horticultural Plant Journal 2024年第4期10卷 1007-1019页

作者： Jorge Aleman-Baez Jose Fernando Acevedo-zamora Johan Bucher Chengcheng Cai Roeland e.Voorrips Guusje Bonnema Plant Breeding Wageningen University and ResearchWageningenThe Netherlands

The vegetative development of cabbage(Brassica oleracea ***)passes through seedling,rosette,folding and heading *** that form the rosette are large and mostly *** the following developmental stages,the plants produce leaves that curve inward to produce the leafy *** microRNAs and their target genes have been described participating in leaf development and leaf *** aim of this study is to investigate the role of miRNA-regulated genes in the transition from the rosette to the heading *** compared the mi RNA and gene abundances between emerging rosette and heading *** remove transcripts(miRNAs and genes)whose regulation was most likely associated with plant age rather than the change from rosette to heading stage,we utilized a non-heading collard green(*** ***)morphotype as *** resulted in 33 DeMs and 1998 DeGs with likely roles in the transition from rosette to heading stage in *** these 1998 DeGs,we found enriched GO terms related to DNA-binding transcription factor activity,transcription regulator activity,iron ion binding,and *** predicted the target genes of these 33 DeMs and focused on the subset that was differentially expressed(1998DeGs)between rosette and heading stage leaves to construct mi RNA-target gene interaction *** main finding is a role for miR396b-5p targeting two Arabidopsis thaliana orthologues of GROWTH ReGUlATING FACTORs 3(GRF3)and 4(GRF4)in pointed cabbage head formation.

关键词： Brassica oleracea var.capitata RNA sequencing miRNA-target gene network leafy head formation

Simplified seismic scenario analysis of existing masonry buildings accounting for local site effects

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Frontiers of Structural and Civil engineering 2024年第2期18卷 309-318页

作者： Ayşe e.ÖZSOYÖZBAY Işıl SANRI KARAPINAR Zehra N.KUTlU İsmail e.KIlIÇ Department of Civil engineering Maltepe UniversityIstanbul 34857Turkey School of engineering and Construction Oryx Universal CollegeDoha 12253Qatar

This study discusses the effects of local sites and hazard amplification on the seismic vulnerability assessment of existing masonry *** this context,a rapid seismic evaluation procedure was implemented on an old masonry building stock in the historical center Galata,located inİstanbul,to determine the seismic risk priority of the built *** scenarios were generated for all soil classes,different moment magnitudes,and source-to-site distances to obtain more accurate results for the seismic vulnerability assessment of the studied building ***,damage distributions estimated under nine different scenarios with/without site effects were compared and illustrated in maps to discuss changes in vulnerability owing to amplification *** this study,by re-examining the rapid seismic evaluation procedure by including geo-hazard-based assessment,the importance of site effects on the vulnerability and risk assessment of built heritage was *** proposed framework integrating field data and local site effects is believed to advance the current applications for vulnerability assessment of masonry buildings and provide an improvement in the application of rapid seismic assessment procedures with more reliable results.

关键词： masonry buildings seismic vulnerability assessment cultural heritage local site effect

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On B(5,20)2-Groups

Algebra Colloquium 2024年第3期31卷 429-440页

作者： e.A.Alhassan Y.l.Tan Y.li School of Mathematical Sciences Jiangsu UniversityZhenjiangJiangsu 212013China Department of Mathematics Brock UniversitySt.CatharinesOntario L2S 3A1Canada

A finite group G is said to be a B(n,k)group if for any n-element subset[a_(1),…,a_(n)]of G,|{a_(i)a_(j)|1≤i,j≤n}|≤*** is of interest to characterize the structure of B(n,k)groups for n(n+1)/2≤k≤n^(2)-*** B(5,k)groups for 15≤k≤19 have been investigated by several *** this paper,we give a complete characterization of B(5,20)2-groups by showing there are five classes of such groups which are nontrivial and nonabelian.

关键词： B(n,k)groups small squaring property central extension GAP

When Fleeing Matters:Differences in escape Behaviours of Three Northeast Asian Anurans

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Asian Herpetological Research 2024年第1期15卷 41-48页

作者： Yoonjung YI Zoljargal PUReVDORJ Irina MASlOVA Yikweon JANG Amaël BORZÉe laboratory of Animal Behaviour and Conservation College of Life SciencesNanjing Forestry UniversityNanjing 210037JiangsuChina Division of ecoScience and Department of life Sciences Ewha Womans UniversitySeoul 03760Republic of Korea Department of Biology School of MathematicsMongolian State University of EducationUlaanbaatar 210648Mongolia Department of Forest and environmental Resources Chungnam National UniversityDaejeon 34134Republic of Korea Federal Scientific Center of the east Asia Terrestrial Biodiversity Far Eastern Branch of Russian Academy of SciencesVladivostok 690022Russia

Prey species may have their own optimal escape strategy to balance predation risks and the energetic cost of *** species have an advantage when maintaining a short fleeing distance,while others may favour an earlier escape based on microhabitat,size,or body ***,we examined the escape behaviour of the three syntopic Northeast Asian anuran species:Mongolian toads(Strauchbufo raddei),Amur brown frogs(Rana amurensis),and Japanese treefrogs(Dryophytes japonicus)in Mongolia,Russia,China and DPR *** examined flight initiation distance(FID;the distance from a potential predator to the point when the individual starts to flee)and distance fled(DF;distance between flight initiation and flight termination points)of each species and the effects of microhabitat,sex,and body *** raddei and *** had a longer FID than ***,and *** also had a longer DF than *** trends remained similar when dividing FID and DF by a size proxy(snout-vent length)for all *** suggests that the treefrog *** used a strategy to stay immobile even when they were detected,and the toad *** reacted quicker and more sensitively to predators despite the presence of *** *** had a significantly longer FID than males suggesting that females are more sensitive to predation risk in this species,but body size was not significant for any of the three *** results indicate that the three sympatric species have different escaping strategies,likely related to differences in physiology and crypticity.

关键词： amphibian distance fled escape behaviour flight initiation distance predation

Performance of evolutionary optimized machine learning for modeling total organic carbon in core samples of shale gas fields

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Petroleum 2024年第1期10卷 150-164页

作者： leonardo Goliatt C.M.Saporetti l.C.Oliveira e.Pereira Department of Computational and Applied Mechanics Federal University of Juiz de Fora Department of Computational Modeling Polytechnic Institute Rio de Janeiro State University Petrobras Department of Stratigraphy and Paleontology Rio de Janeiro State University

Rock samples' TOC content is the best indicator of the organic matter in source rocks. The origin rock samples' analysis is used to calculate it manually by specialists. This method requires time and resources because it relies on samples from many well intervals in source rocks. Therefore, research has been done to aid this effort. Machine learning algorithms can estimate total organic carbon instead of well logs and stratigraphic studies. In light of these efforts, the current work present a study on automating the total organic carbon estimation using machine learning approaches improved by an evolutionary methodology to give the model flexibility and precision. Genetic algorithms, differential evolution, particle swarm optimization, grey wolf optimization, artificial bee colony, and evolution strategies were used to improve machine learning models to predict TOC. The six metaheuristics were integrated into four machine learning methods: extreme learning machine, elastic net linear model, linear support vector regression, and multivariate adaptive regression splines. Core samples from the YuDong-Nan shale gas field, located in the Sichuan basin, were used to evaluate the hybrid strategy. The findings show that combining machine learning models with an evolutionary algorithms in a hybrid fashion produce flexible models that accurately predict TOC. The results show that, independent of the metaheuristic used to guide the model selection, optimized extreme learning machines attained the best performance scores according to six metrics. Such hybrid models can be used in exploratory geological research,particularly for unconventional oil and gas resources.

关键词： Total organic carbon Hybrid models Automated machine learning evolutionary algorithms Geology

exploring the effects of anthropogenic disturbance on predator inspection activity in Trinidadian guppies

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Current Zoology 2024年第1期70卷 109-111页

作者： Alix J.P Brusseau laurence e.A.Feyten Adam l.Crane Grant e.Brown Department of Biology Concordia UniversityMontrealQCH4B 1R6Canada Department of Biomedical Sciences WCVMUniversity of SaskatchewanSaskatoonSKCanada

Prey animals are often faced with uncertainty due to having imperfect information regarding current local conditions,including predation risks and the availability of reliable foraging opportunities(Dall 2010).As this uncertainty increases,the probability of making costly behavioral errors also increases,leading to more risk averse behavioral tactics(Feyten et al.2019).For example,Trinidadian guppies Poecilia reticulata are far more risk averse when faced with multiple unknown sources of risk assessment information than when faced with a mix of known and unknown cues(Feyten et al.2019).Prey can reduce uncertainty by gathering and integrating private and social information regarding current risk levels within microhabitats(Dall 2010;Munoz and Blumstein 2012).

关键词： human disturbance information availability information reliability predator-prey interactions risk assessment uncertainty

In situ Hydrothermal Oxidation of Ternary FeCoNi Alloy electrode for Overall Water Splitting

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energy & environmental Materials 2024年第2期7卷 161-170页

作者： Yuwei Chen lixia Yang Chao li Yuqiu Wu Xiao lν Hairen Wang Jun'e Qu Key laboratory for the Green Preparation and Application of Functional Materials Hubei Key Laboratory of Polymer MaterialsSchool of Materials Science and EngineeringHubei UniversityWuhan 430062China Faculty of Material science and Chemistry China University of GeosciencesWuhan 430074China

exploring noble metal-free catalyst materials for high efficient electrochemical water splitting to produce hydrogen is strongly desired for renewable energy *** this article,a novel bifunctional catalytic electrode of insitu-grown type for alkaline water splitting based on FeCoNi alloy substrate has been successfully prepared via a facile one-step hydrothermal oxidation route in an alkaline hydrogen peroxide *** shows that the matrix alloy with the atom ratio 4∶3∶3 of Fe∶Co∶Ni can obtain the best catalytic performance when hydrothermally treated at 180℃for 18 h in the solution containing 1.8 M hydrogen peroxide and 3.6 M sodium *** as-prepared Fe_(0.4)Co_(0.3)Ni_(0.3)-1.8 electrode exhibits small overpotentials of only 184 and 175 mV at electrolysis current density of 10 mA cm^(-2)for alkaline OeR and HeR processes,*** overall water splitting at electrolysis current density of 10 mA cm^(-2)can be stably delivered at a low cell voltage of 1.62 *** characteristics including the large specific surface area,the high surface nickel content,the abundant catalyst species,the balanced distribution between bivalent and trivalent metal ions,and the strong binding of in-situ naturally growed catalytic layer to matrix are responsible for the prominent catalytic performance of the Fe_(0.4)Co_(0.3)Ni_(0.3)-1.8 electrode,which can act as a possible replacement for expensive noble metal-based materials.

关键词： alkaline water electrolysis bifunctional electrocatalyst FeCoNi alloy hydrothermal oxidation in-situ growing

Using proteomics to compare the molecular structures of sulfide and permeate-depilated sheepskins

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Collagen and leather 2024年第1期6卷 70-84页

作者： Yi-Hsuan Tu Trevor S.loo Mark l.Patchett Gillian e.Norris School of Natural Sciences Massey UniversityPalmerston NorthNew Zealand

An environmentally friendly method using real or artificial bovine milk permeate to both depilate and preserve sheepskins has been reported which completely and cleanly removed the wool from the hair follicle and had no detrimental effects on the skin.A proteomic analysis,assessing the relative abundance of proteins in matched permeate-depilated and chemically depilated(sulfide)sheepskins,showed variations in the levels of specific collagen types in the skin's basement membrane and other proteins associated with the *** findings were corroborated by biochemical analyses of matched permeate depilated and raw skin samples,and provide clues to the mechanism of non-invasiveand complete *** also support the observation that permeate-depilated skins were smoother than their sulfide-depilated counterparts and resulted in leather with a superior surface.

关键词： Collagen Collagen crosslinks Glycosaminoglycan Proteomics Relative abundance