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Rare earth element enrichment in sedimentary phosphorites formed during the Precambrian-cambrian transition,Southwest china

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Geoscience frontiers 2024年第2期15卷 334-348页

作者： Jieqi Xing Yuhang Jiang Haiyang Xian Wubin yang Yiping yang Hecai Niu Hongping He Jianxi Zhu cAS Key Laboratory of Mineralogy and Metallogeny Guangdong Provincial Key Laboratory of Mineral Physics and MaterialsGuangzhou Institute of GeochemistryChinese Academy of Sciences(CAS)Guangzhou 510640China cAS center for Excellence in Deep Earth Science Guangzhou 510640China University of chinese Academy of Sciences Beijing 100049China

Numerous sedimentary phosphorites in Southwest china were formed around the Precambrian–cambrian transition(Pc–c),including the upper Ediacaran Doushantuo formation and lower cambrian Gezhongwu *** Gezhongwu phosphorites in Zhijin exhibit marked rare earth element(REE)enrichment(>1000 ppm),and may represent new REE *** the main characteristics of the Gezhongwu phosphorites have been well constrained,the REE enrichment mechanisms remain *** undertook a comparative study of three typical sedimentary phosphorites with variable REE contents formed at the Pc–c transition in central Guizhou Province,Southwest *** include sections A and B of the Doushantuo phosphorites(560±8 Ma)from the Weng’an area(i.e.,WA-A and WA-B),and the Gezhongwu phosphorites(527±24 Ma)from the Zhijin area(ZJ).The phosphorites were investigated with state-of-the-art macroscale to nanoscale analytical *** contrast to the extraordinary REE enrichment in the ZJ phosphorites(average RREE=1157 ppm),the phosphorites in WA-A(average RREE=234 ppm)and WA-B(average RREE=114 ppm)are *** mapping by laser ablation–inductively coupled plasma–mass spectrometry,along with transmission electron microscopy analyses,showed the REEs in the studied phosphorites are hosted in nanoscale *** 87Sr/86Sr and Y/Ho ratios of the francolite grains indicate that greater terrigenous input may have led to more REE enrichment in the WA-A than WA-B phosphorites,but this cannot explain the extraordinary REE enrichment in the ZJ *** f/P_(2)O_(5)values of the francolite grains in the ZJ phosphorites(~0.097)are higher than those in the WA-A(~0.084)and WA-B(~0.084)phosphorites,and the grain size of the francolite in the ZJ phosphorites(~89.9 nm)is larger than those in the WA-A(~56.6 nm)and WA-B(~57.4 nm)phosphorites,indicative of more intense reworking of the ZJ than WA phosphorites during early diagenesis.A plot of Nd concentration versus ce/ce^(*)r

关键词： REE enrichment francolite,phosphorites Sedimentary reworking Rate of sedimentary

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Predicting grain size-dependent superplastic properties in friction stir processed ZK30 magnesium alloy with machine learning methods

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Journal of Magnesium and Alloys 2024年第5期12卷 1931-1943页

作者： farid Bahari-Sambran fernando carreno c.M.cepeda-Jiménez Alberto Orozco-caballero Physical Metallurgy Department CENIM-CSICAv.Gregorio del Amo 828040 MadridSpain Department of Mechanical Engineering Chemistry and Industrial DesignPolytechnic University of MadridRonda de Valencia 328012MadridSpain

The aim of this work is to predict,for the first time,the high temperature flow stress dependency with the grain size and the underlaid deformation mechanism using two machine learning models,random forest(Rf)and artificial neural network(ANN).With that purpose,a ZK30 magnesium alloy was friction stir processed(fSP)using three different severe conditions to obtain fine grain microstructures(with average grain sizes between 2 and 3μm)prone to extensive superplastic *** three friction stir processed samples clearly deformed by grain boundary sliding(GBS)deformation mechanism at high *** maximum elongations to failure,well over 400% at high strain rate of 10^(-2)s^(-1),were reached at 400℃ in the material with coarsest grain size of 2.8μm,and at 300℃ for the finest grain size of 2μ***,the superplastic response decreased at 350℃ and 400℃ due to thermal instabilities and grain coarsening,which makes it difficult to assess the operative deformation mechanism at such *** work highlights that the machine learning models considered,especially the ANN model with higher accuracy in predicting flow stress values,allow determining adequately the superplastic creep behavior including other possible grain size scenarios.

关键词： Machine learning Artificial intelligence Magnesium alloys Superplasticity friction stir processing Grain coarsening

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“嫌贫爱富”抑或“扶危济困”:农户民间放贷选择偏好研究

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财贸研究 2024年第1期35卷 33-46页

作者：杨少雄 calum G.Turvey 孔荣西北农林科技大学陕西杨凌712100 康奈尔大学纽约伊萨卡14853

基于合约、借方和贷方三方面特征设计农户民间放贷离散选择实验,依据陕西、山东两省289户农户实验数据,构建效用相互依赖模型考察农户民间放贷选择偏好的内在机理,采用Mixed Logit模型探究农户选择偏好及其异质性来源。研究结果表明,农... 详细信息

基于合约、借方和贷方三方面特征设计农户民间放贷离散选择实验,依据陕西、山东两省289户农户实验数据,构建效用相互依赖模型考察农户民间放贷选择偏好的内在机理,采用Mixed Logit模型探究农户选择偏好及其异质性来源。研究结果表明,农户民间放贷选择中经济理性与道义理性偏好并存。其中,经济理性体现为农户偏好向亲戚或信用水平较高的借方放贷,农户手头资金紧张时放贷意愿减弱;道义理性体现为农户偏好向经济情况比自己差、曾与自己有过互动经历且用途为生活性应急需求的借方放贷,农户拒贷有压力时放贷意愿增强。进一步研究发现,农户民间放贷选择偏好存在异质性,表现为受教育程度会强化放贷农户经济理性偏好,家庭收入会强化放贷农户道义理性偏好,风险偏好型放贷农户的道义理性偏好更弱,而山东省放贷农户的经济理性和道义理性偏好均高于陕西省。

关键词：农户民间放贷效用相互依赖模型选择偏好异质性来源离散选择实验

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Optimized NPK fertilizer recommendations based on topsoil available nutrient criteria for wheat in drylands of china

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Journal of Integrative Agriculture 2024年第7期23卷 2421-2433页

作者： Wenjie yang Jie Yu Yanhang Li Bingli Jia Longgang Jiang Aijing Yuan Yue Ma Ming Huang Hanbing cao Jinshan Liu Weihong Qiu Zhaohui Wang Key Laboratory of Plant Nutrition and Agri-environment in Northwest china Ministry of Agriculture and Rural Affairs/College of Natural Resources and EnvironmentNorthwest A&F UniversityYangling 712100China

The optimized management of crop fertilization is very important for improving crop yield and reducing the consumption of chemical *** nutrient values can be used for evaluating the nutritional status of a crop,and they reflect the nutrient concentrations above which the plant is sufficiently supplied for achieving the maximum potential *** on on-farm surveys of 504 farmers and 60 field experimental sites in the drylands of china,we proposed a recommended fertilization method to determine nitrogen(N),phosphorus(P),and potassium(K)fertilizer input rates for wheat production,and then validated the method by a field experiment at 66 different sites in northern *** results showed that wheat grain yield varied from 1.1 to 9.2 t ha^(-1),averaging 4.6 t ha^(-1),and it had a quadratic relationship with the topsoil(0-20 cm)nitrate N and soil available P contents at ***,yield was not correlated with the inputs of N,P,and K *** on the relationship(exponential decay model)between 95–105%of the relative yield and topsoil nitrate N,available P,and available K contents at wheat harvest from 60 field experiments,the topsoil critical nutrient values were determined as 34.6,15.6,and 150 mg kg^(-1)for soil nitrate N,available P,and available K,***,based on five groups of relative yield(>125%,115–125%,105–115%,95–105%,andfive groups of topsoil critical nutrient levels and fertilization coefficients(fc)were ***,we proposed a new method for calculating the recommended fertilizer input rate as:fr=Gy×Nr×fc,where fr is the recommended fertilizer(N/P/K)input rate;Gy is the potential grain yield;Nr is the N(N_(rN)),P(N_(rP)),and K(N_(rK))nutrient requirements for wheat to produce 1,000 kg of grain;and fc is a coefficient for N(N_c)/P(P_c)/K(K_c.f.rtilizer.A 2-year validated experiment confirmed that the new method reduced N fertilizer input by 17.5%(38.5 kg N ha^(-1))and P fertilizer i

关键词： fertilization method dryland wheat soil nutrient critical value soil nitrogen topsoil nutrients

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Overexpression of the transcription factor MdWRKY115 improves drought and osmotic stress tolerance by directly binding to the MdRD22 promoter in apple

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Horticultural Plant Journal 2024年第3期10卷 629-640页

作者： Qinglong Dong Yi Tian Xuemei Zhang Dingyue Duan He Zhang Kaiyu yang Peng Jia Haoan Luan Suping Guo Guohui Qi Ke Mao fengwang Ma college of forestry Hebei Agricultural UniversityBaodingHebei 071001China National Engineering Research center for Agriculture in Northern Mountainous Areas Agricultural Technology Innovation Center in Mountainous Areas of Hebei ProvinceHebei Agricultural UniversityBaodingHebei 071001China State Key Laboratory of crop Stress Biology for Arid Areas Shaanxi Key Laboratory of AppleCollege of HorticultureNorthwest A&F UniversityYanglingShaanxi 712100China college of Horticulture Hebei Agricultural UniversityBaodingHebei 071001China

Abiotic stress reduces plant yield and *** transcription factors play key roles in abiotic stress responses in plants,but the molecular mechanisms by which WRKY transcription factors mediate responses to drought and osmotic stresses in apple(Malus×domestica Borkh.)remain ***,we functionally characterized the apple GroupⅢWRKY gene ***-PcR analysis showed that MdWRKY115 expression was up-regulated by drought and osmotic *** activity analysis revealed that the promoter activity of MdWRKY115 was enhanced under osmotic *** localization and transactivation assays indicated that MdWRKY115 was localized to the nucleus and had a transcriptional activity domain at the N-terminal *** analysis revealed that the overexpression of MdWRKY115 in Arabidopsis plants and in apple callus markedly enhanced their tolerance to drought and osmotic *** affinity purification sequencing showed that MdWRKY115 binds to the promoter of the stress-related gene *** binding was further verified by an electrophoretic mobility shift ***,these findings suggest that MdWRKY115 is an important regulator of osmotic and drought stress tolerance in apple.

关键词： Apple MdWRKY115 Osmotic stress Drought stress function analysis

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焊后热处理对SA-182f1和SA-106c钢接头显微组织和力学性能的影响

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热处理 2024年第3期39卷 17-20页

作者：杨博杨红权柳云天曲瑞哈尔滨锅炉厂有限责任公司黑龙江哈尔滨150046 低碳热力发电技术与装备全国重点实验室黑龙江哈尔滨150046

采用钨极氩弧焊和焊条电弧焊焊接SA-182f1和SA-106c钢.对焊接接头进行了615℃保温8h的消除应力处理.检测了焊接接头热处理前、后的显微组织和力学性能.结果表明:热处理前、后焊接接头的拉伸和冲击性能均满足要求,消除应力处理使接头拉... 详细信息

采用钨极氩弧焊和焊条电弧焊焊接SA-182f1和SA-106c钢.对焊接接头进行了615℃保温8h的消除应力处理.检测了焊接接头热处理前、后的显微组织和力学性能.结果表明:热处理前、后焊接接头的拉伸和冲击性能均满足要求,消除应力处理使接头拉伸性能降低、冲击韧度提高;热处理前后焊接接头的显微组织没有差异.

关键词：异种钢焊后热处理焊接接头力学性能

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Magnetic phase transition and continuous spin switching in a high-entropy orthoferrite single crystal

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frontiers of physics 2024年第2期19卷 157-167页

作者： Wanting yang Shuang Zhu Xiong Luo Xiaoxuan Ma chenfei Shi Huan Song Zhiqiang Sun Yefei Guo Yuriy Dedkov Baojuan Kang Jin-Ke Bao Shixun cao Department of Physics Shanghai UniversityShanghai 200444China Materials Genome Institute and International center for Quantum and Molecular Structures Shanghai UniversityShanghai 200444China School of Physics Southeast UniversityNanjing 211189China Shanghai Key Laboratory of High Temperature Superconductors Shanghai UniversityShanghai 200444China

Rare-earth orthoferrite REfeO_(3)(where RE is a rare-earth ion)is gaining *** created a high-entropy orthoferrite(Tm_(0.2)Nd_(0.2)Dy_(0.2)Y_(0.2)Yb_(0.2))feO_(3)(HEOR)by doping five RE ions in equimolar ratios and grew the single crystal by optical floating zone *** strongly tends to form a single-phase structure stabilized by high configurational *** the low-temperature region(11.6‒14.4 K),the spin reorientation transition(SRT)ofΓ_(2)(f_(x),c_(y),G_(z))‒Γ_(24)‒Γ_(4)(G_(x),A_(y),f_(z))*** weak ferromagnetic.f.)moment,which comes from the fe sublattices distortion,rotates from the a-to *** two-step dynamic processes(Γ_(2)‒Γ_(24)‒Γ_(4))are identified by Ac susceptibility *** in HEOR can be tuned in the range of 50‒60000 Oe,which is an order of magnitude larger than that of orthoferrites in the peer system,making it a candidate for high-field spin *** spin-switching(SSW)and continuous spin-switching(cSSW)effects occur under low magnetic.f.elds due to the strong interactions between RE‒fe *** cSSW effect is tunable between 20‒50 Oe,and hence,HEOR potentially can be applied to spin modulation ***,because of the strong anisotropy of magnetic entropy change()and refrigeration capacity(Rc)based on its high configurational entropy,HEOR is expected to provide a novel approach for refrigeration by altering the orientations of the crystallographic axes(anisotropic configurational entropy).

关键词： high-entropy oxide rare-earth orthoferrite spin reorientation transition spin switching magnetocaloric effect

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Numerical Analysis of the Magnetic Dipole Effect on a Radiative ferromagnetic Liquid flowing over a Porous Stretched Sheet

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fluid Dynamics & Materials Processing 2024年第2期20卷 293-310页

作者： G.Dharmaiah f.Mebarek-Oudina K.S.Balamurugan N.Vedavathi Department of Mathematics Narasaraopeta Engineering CollegeNarasaraopetIndia Department of Physics Faculty of SciencesUniversity of 20 Août 1955-SkikdaSkikdaAlgeria Department of Mathematics RVR&JC College of EngineeringGunturIndia Department of Mathematics Koneru Lakshmaiah Education FoundationVaddeswaramIndia

The effects of a magnetic dipole on a nonlinear thermally radiative ferromagnetic liquidﬂowing over a stretched surface in the presence of Brownian motion and thermophoresis are *** means of a similarity transformation,ordinary differential equations are derived and solved afterwards using a numerical(the BVP4c)*** impact of various parameters,namely the velocity,temperature,concentration,is presented *** is shown that the nanoparticles properties,in conjunction with the magnetic dipole effect,can increase the thermal conductivity of the engineered nanoﬂuid and,consequently,the heat *** with earlier studies indicates high accuracy and effectiveness of the numerical *** increase in the Brow-nian motion parameter and thermophoresis parameter enhances the concentration and the related boundary *** skin-friction rises when the viscosity parameter is increased.A larger value of the ferromagnetic para-meter results in a higher skin-friction and,vice versa,in a smaller Nusselt number.

关键词： Brownian motion thermo-phoresis radiation magnetic dipole BVP4c non-linear

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fluorine-Doped High-Performance Li_(6)PS_(5)cl Electrolyte by Lithium fluoride Nanoparticles for All-Solid-State Lithium-Metal Batteries

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Transactions of Tianjin University 2024年第3期30卷 250-261页

作者： Xiaorou cao Shijie Xu Yuzhe Zhang Xiaohu Hu Yifan Yan Yanru Wang Haoran Qian Jiakai Wang Haolong chang fangyi cheng Yongan yang Institute of Molecular Plus School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China Haihe Laboratory of Sustainable chemical Transformations Tianjin 300192China Key Laboratory of Advanced Energy Materials chemistry(Ministry of Education) Nankai UniversityTianjin 300071China

All-solid-state lithium-metal batteries(ASSLMBs)are widely considered as the ultimately advanced lithium batteries owing to their improved energy density and enhanced safety *** various solid electrolytes,sulfide solid electrolyte(SSE)Li_(6)PS_(5)cl has garnered significant ***,its application is limited by its poor cyclability and low critical current density(ccD).In this study,we introduce a novel approach to enhance the performance of Li_(6)PS_(5)cl by doping it with fluorine,using lithium fluoride nanoparticles(Lifs)as the doping *** f-doped electrolyte Li_(6)PS_(5)cl-0.2Lif(nano)shows a doubled ccD,from 0.5 to 1.0 mA/cm^(2) without compromising the ionic conductivity;in fact,conductivity is enhanced from 2.82 to 3.30 mS/cm,contrary to the typical performance decline seen in conventionally doped Li_(6)PS_(5)cl *** symmetric Li|SSE|Li cells,the lifetime of Li_(6)PS_(5)cl-0.2Lif(nano)is 4 times longer than that of Li_(6)PS_(5)cl,achieving 1500 h vs.371 h under a charging/discharging current density of 0.2 mA/cm^(2).In Li|SSE|LiNbO_(3)@NcM721 full cells,which are tested under a cycling rate of 0.1 c at 30℃,the lifetime of Li_(6)PS_(5)cl-0.2Lif(nano)is four times that of Li_(6)PS_(5)cl,reaching 100 cycles vs.26 ***,the doping of nano-Lif off ers a promising approach to developing high-performance Li_(6)PS_(5)cl for ASSLMBs.

关键词： Sulfide solid electrolyte All-solid-state lithium batteries Li_(6)PS_(5)cl Lithium fluoride f-doping

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Dynamical study of varicella-zoster virus model in sense of Mittag-Leffler kernel

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International Journal of Biomathematics 2024年第3期17卷 153-183页

作者： Qura Tul Ain Aziz Khan Thabet Abdeljawad J.f.Gomez-Aguilar Saleem Riaz Department of Mathematics Guizhou University GuiyangGuizhou 550025P.R.China Department of Mathematics and Sciences Prince Sultan University P.O.Bor 66833 11586 RiyadhSaudi Arabia Department of Medical Research china Medical University Taichung 40402Taiwan cONAcyT-Tecnologico Nacional de Mécico/cENIDET Interior Internado Palmira S/N Col.Palmira C.P.62490CuernavacaMorelosMécico IConsejo Academico Universidad Virtual CNCIMonterreyMécico School of Automation Northwestern Polytechnical University 170072 Xian P.R.China

The primary varicella-zoster virus(VzV)infection that causes chickenpox(also known as varicella),spreads quickly among people and,in severe circumstances,can cause to fever and *** this paper,the Mittag-Leffler fractional operator is used to examine the mathematical representation of the *** fractional-order differential equations are created in terms of the disease's dynamical analysis such as S:Susceptible,V:Vaccinated,E:Exposed,I:Infectious and R:*** derive the existence criterion,positive solution,Hyers-Ulam stability,and boundedness of results in order to examine the suggested fractional-order model's ***,some numerical examples for the VzV model of various fractional orders are shown with the aid of the generalized Adams-Bashforth-Moulton approach to show the viability of the obtained results.

关键词： Varicella-zoster virus model Hyers-Ulam stability ABc.f.actional operator Schauder fix point theory numerical analysis

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