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The magnetic properties and magnetocaloric effects in binary R-T(R = Pr,Gd,Tb,Dy,Ho,Er,Tm;T = Ga,Ni,Co,Cu)intermetallic compounds

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Chinese Physics B 2017年第2期26卷 1-41页

作者： xin-qi zheng Bao-Gen Shen School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China Institute of Physics Chinese Academy of Sciences and University of Chinese Academy of Sciences Beijing 100190 China

In this paper, we review the magnetic properties and magnetocaloric effects（MCE） of binary R–T（R = Pr, Gd, Tb,Dy, Ho, Er, Tm; T = Ga, Ni, Co, Cu） intermetallic compounds（including RGa series, RNi series, R_（12）Co_7 series, R_3 Co series and RCu_2series）, which have been investigated in detail in the past several years. The R–T compounds are studied by means of magnetic measurements, heat capacity measurements, magnetoresistance measurements and neutron powder diffraction measurements. The R–T compounds show complex magnetic transitions and interesting magnetic *** types of magnetic transitions are investigated and confirmed in detail by multiple approaches. Especially, most of the R–T compounds undergo more than one magnetic transition, which has significant impact on the magnetocaloric effect of R–T compounds. The MCE of R–T compounds are calculated by different ways and the special shapes of MCE peaks for different compounds are investigated and discussed in detail. To improve the MCE performance of R–T compounds,atoms with large spin（S） and atoms with large total angular momentum（J） are introduced to substitute the related rare earth atoms. With the atom substitution, the maximum of magnetic entropy change（？SM）, refrigerant temperature width（Twidth）or refrigerant capacity（RC） is enlarged for some R–T compounds. In the low temperature range, binary R–T（R = Pr, Gd,Tb, Dy, Ho, Er, Tm; T = Ga, Ni, Co, Cu） intermetallic compounds（including RGa series, RNi series,R_（12）Co_7 series, R_3 Co series and RCu_2series） show excellent performance of MCE, indicating the potential application for gas liquefaction in the future.

关键词： magnetocaloric effect magnetic entropy change magnetic property neutron diffraction magnetic structure

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Current Medical Science 2019年第1期39卷 67-74页

作者： Jing ZHOU Yong-chao WU Bao-jun XIAO Xiao-dong GUO qi-xin zheng Bin WU Department of General Surgery Tongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022China Department of Orthopaedics Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022China

Demyelination of axons plays an important role in the pathology of many spinal cord diseases and *** in demyelinated lesions is primarily performed by oligodendrocyte progenitor cells(OPCs),which generate oligodendrocytes in the developing and mature central nervous *** efficiency of remyelination decreases with *** reports suggest that this decline in remyelination results from impaired OPC recruitment and differentiation during *** the various molecular mechanisms involved in aging,changes in epigenetic modifications have received particular *** DNA methylation is a major epigenetic modification that plays important roles in cellular senescence and organismal ***,we aimed to evaluate the dynamic changes in the global DNA methylation profiles of OPCs derived from rat spinal cords during the aging *** separated and cultured OPCs from the spinal cords of neonatal,4-month-old,and 16-month-old rats and investigated the age-related alterations of genomic DNA methylation levels by using quantitative colorimetric *** determine the potential cause of dynamic changes in global DNA methylation,we further analyzed the activity of DNA methyltransferases(DNMTs)and the expression of DNMT1,DNMT3a,DNMT3b,TET1,TET2,TET3,MBD2,and MeCP2 in the OPCs from each *** results showed the genomic DNA methylation level and the activity of DNMTs from OPCs derived from rat spinal cords decreased gradually during aging,and OPCs from 16-month-old rats were characterized by global *** OPC aging,the mRNA and protein expression levels of DNMT3a,DNMT3b,and MeCP2 were significantly elevated;those of DNMT1 were significantly down-regulated;and no significant changes were observed in those for TET1,TET2,TET3,or *** results indicated that global DNA hypomethylation in aged OPCs is correlated with DNMT1 ***,these data provide important evidence for partly elucidating the mechanism of ag

关键词： T2 mapping Duchenne muscular dystrophy skeletal muscle fat infiltration

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Machine learning technique for prediction of magnetocaloric effect in La(Fe,Si/Al)_(13)-based materials

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Chinese Physics B 2018年第6期27卷 92-97页

作者： Bo Zhang xin-qi zheng Tong-Yun Zhao Feng-Xia Hu Ji-Rong Sun Bao-Gen Shen State Key Laboratory of Magnetism Institute of Physics Chinese Academy of Sciences Beijing 100190 China School of Physical Sciences University of the Chinese Academy of Sciences Beijing 100049 China School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

Data-mining techniques using machine learning are powerful and efficient for materials design, possessing great potential for discovering new materials with good characteristics. Here, this technique has been used on composition design for La（Fe,Si/Al）（13）-based materials, which are regarded as one of the most promising magnetic refrigerants in practice. Three prediction models are built by using a machine learning algorithm called gradient boosting regression tree（GBRT） to essentially find the correlation between the Curie temperature（TC）, maximum value of magnetic entropy change（（？SM）（max））,and chemical composition, all of which yield high accuracy in the prediction of TC and（？SM）（max）. The performance metric coefficient scores of determination（R^2） for the three models are 0.96, 0.87, and 0.91. These results suggest that all of the models are well-developed predictive models on the challenging issue of generalization ability for untrained data, which can not only provide us with suggestions for real experiments but also help us gain physical insights to find proper composition for further magnetic refrigeration applications.

关键词： La(Fe,Si/Al)13-based materials composition design machine learning magnetic refrigeration

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Visible-light-responsive homologous heterostructure of oxynitrides constructed to boost charge separation and water splitting

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Science China Chemistry 2025年第1期68卷 186-191页

作者： Hai Zou Yunfeng Bao Xueshang xin Yu qi Tengfeng Xie Fuxiang Zhang State Key Laboratory of Catalysis Dalian National Laboratory for Clean Energy Dalian Institute of Chemical Physics Chinese Academy of Sciences School of Chemistry and Chemical Engineering Liaoning Normal University College of Chemistry Jilin University

Constructing type II heterostructures represents a widely recognized strategy for enhancing charge separation and photocatalytic efficiency,but it remains challenging to fabricate homologous heterostructures based on visible-light-responsive semiconductors,especially for popularly investigated （oxy）nitrides with low thermal ***,we synthesized a homologous heterostructure （denoted as YTON＿H） based on the oxynitrides of YTaO4-xNyand YTa *** heterostructure exhibits type II band structure alignment and intimate interface achieved through a magnesium （Mg） powder-assisted nitridation *** with widely reported heterologous heterostructures,the as-obtained YTON＿H homologous heterostructure could similarly exhibit enhanced charge separation as well as photocatalytic water splitting performance with respect to its counterparts(YTaO4-xNyand YTaON2).Meanwhile,detailed structural characterizations and spectroscopy analysis have been made to confirm the formation of heterostructure and promotion of spatial charge separation.

关键词： charge separation heterostructure oxynitride photocatalysis visible light

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Distribution and mapping of temperate savanna in the sandy lands of eastern China

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Science China Earth Sciences 2025年第1期68卷 128-141页

作者： Xiaoya LI Feng WANG Tao DUAN Kaijie YANG Bin YANG Chunmei WANG xin TIAN qi LU Institute of Ecological Conservation and Restoration Institute of Desertification Studies Chinese Academy of Forestry Institute of Desertification Institute of Desertification Studies Chinese Academy of Forestry Institute of Great Green Wall Satellite Application Centre for Ecology and Environment MEE Institute of Microelectronics Chinese Academy of Sciences Aerospace Information Research Institute Chinese Academy of Sciences Institute of Forest Resource Information Techniques Chinese Academy of Forestry

Savannas are distributed globally across various *** perform a significant socioeconomic role in regulating net primary productivity and the terrestrial carbon *** to the high spatial heterogeneity induced by the mixed distribution of trees and grasses,current global land-cover classification maps often classify savannas as forests or grasslands Temperate savannas in China cover a vast area,yet their spatial patterns and extent remain poorly *** study developed a novel remote sensing temperate savannas mapping method by integrating very high-resolution （VHR） unmanned aerial vehicle （UAV） and GF-6 satellite imagery based on the vegetation structure characteristics of temperate savannas using the FAO definition of *** and validation datasets were collected from VHR UAV imagery covering the main temperate savannah types with a ground area of 1818 *** fractional woody vegetation cover （FWVC） and fractional herbaceous vegetation cover （FHVC） in temperate savannas were estimated by integrating Classification and Regression Tree and Random Forest *** current distribution of temperate savannas in the Horqin and Otindag Sandy Lands of Eastern China was mapped to a unit area of 0.5 *** root-mean-square error （RMSE） values for the FWVC and FHVC models were 10.69% and 11.67%,and the R2values were 0.66 and 0.63,*** assessment indicated that the new temperate savanna map had high identification accuracy,with a Kappa coefficient of 0.70,overall accuracy of 0.88,and average accuracy of *** savannas in the sandy lands of eastern China were primarily distributed in the northern Horqin Sandy Land the central and eastern regions of the Otindag Sandy Land,and the transition zone from the southern slopes of the Greater Khingan Mountains to the plains,covering a total area of 3.27×10～6 *** main savannah types were elm,oak/maple,and shrub *** savannas were widely distributed in the Otindag Sandy

关键词： Temperate savanna UAV imagery GF-6 Fractional woody vegetation cover Fractional herbaceous vegetation cover Machine learning

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Large inverse and normal magnetocaloric effects in HoBi compound with nonhysteretic first-order phase transition

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Chinese Physics B 2022年第7期31卷 539-543页

作者： Yan Zhang You-Guo Shi Li-Chen Wang xin-qi zheng Jun Liu Ya-Xu Jin Ke-Wei Zhang Hong-Xia Liu Shuo-Tong Zong Zhi-Gang Sun Ji-Fan Hu Tong-Yun Tong Bao-Gen Shen School of Materials Science and Engineering Taiyuan University of Science and TechnologyTaiyuan 030024China Institute of Physics Chinese Academy of SciencesBeijing 100190China Laboratory of Magnetic and Electric Functional Materials and Applications The Key Laboratory of Shanxi ProvinceTaiyuan 030024China School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China

HoBi single crystal and polycrystalline compounds with Na Cl-type structure are successfully obtained,and their magnetic and magnetocaloric properties are studied in *** temperature increasing,Ho Bi compound undergoes two magnetic transitions at 3.7 K and 6 K,*** transition temperature at 6 K is recognized as an antiferromagneticto-paramagnetic(AFM–PM)transition,which belongs to the first-order magnetic phase transition(FOMT).It is interesting that the Ho Bi compound with FOMT exhibits good thermal and magnetic ***,a large inverse and normal magnetocaloric effect(MCE)is found in Ho Bi single crystal in the H||[100]direction,and the positive?SMpeak reaches 13.1 J/kg·K under a low field change of 2 T and the negative?S_(M)peak arrives at-18 J/kg·K under a field change of5 *** excellent properties are expected to be applied to some magnetic refrigerators with special designs and functions.

关键词： magnetocaloric effect antiferromagnetic rare-earth compounds

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山岳型景区旅游饭店与城市饭店的差异分析——以黄山风景区为例

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地域研究与开发 2005年第3期24卷 81-84页

作者：朱国兴齐新征黄山学院旅游系安徽黄山245021

饭店是旅游业的重要组成,不同区位的饭店存在着巨大差异。文章以黄山风景区的旅游饭店为实证,针对饭店的功能项目、产品价格、员工状况等方面进行分析,并通过与所在地区的城市饭店进行比较,探讨山岳型景区旅游饭店与城市饭店的差异表现... 详细信息

饭店是旅游业的重要组成,不同区位的饭店存在着巨大差异。文章以黄山风景区的旅游饭店为实证,针对饭店的功能项目、产品价格、员工状况等方面进行分析,并通过与所在地区的城市饭店进行比较,探讨山岳型景区旅游饭店与城市饭店的差异表现及形成机制,旨在为山岳型风景区饭店的发展和建设提供有益参考。

关键词：饭店山岳景区城市世界文化自然遗产黄山

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半夏PtPAL基因的克隆、表达与酶动力学分析

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作物学报 2021年第10期47卷 1941-1952页

作者：何潇刘兴辛正琦谢海艳辛余凤吴能表西南大学生命科学学院重庆400715 三峡库区生态环境教育部重点实验室重庆400715 重庆市大足中学重庆402360

本研究以半夏为研究对象,基于其转录组数据克隆获得1个苯丙氨酸解氨酶基因,命名为PtPAL,通过DNAMAN、MEGA等生物信息学软件进行序列结构与系统进化分析表明,该基因核酸序列长度为2289 bp,编码762个氨基酸,终止密码子为TAA,PtPAL与单子... 详细信息

本研究以半夏为研究对象,基于其转录组数据克隆获得1个苯丙氨酸解氨酶基因,命名为PtPAL,通过DNAMAN、MEGA等生物信息学软件进行序列结构与系统进化分析表明,该基因核酸序列长度为2289 bp,编码762个氨基酸,终止密码子为TAA,PtPAL与单子叶植物百合PAL相似度达78%,具有PAL-HAL、PLN02457、phe_am_lyase、Lyase_aromatic及HutH结构域,属于苯丙氨酸解氨酶家族成员(Lyase_I_like Superfamily)。半夏PtPAL与单子叶植物百合、菠萝和油棕亲缘关系较近,归于单子叶植物。采用实时荧光定量PCR分析PtPAL在不同组织间的表达情况表明,PtPAL基因在叶中表达量最高,其次是块茎和根,花中表达量最低。通过对半夏PtPAL基因进行功能表达分析发现, PtPAL重组蛋白可以高效催化L-Phe生成t-CA,且催化反应最适pH与温度分别为9.0、70℃;PtPAL的K_(m)、V_(max)、K_(cat)和K_(cat)/K_(m)分别为0.89 mmol L^(-1)、63.96 nKat mg^(–1)、6.56 s^(–1)和7.37×10^(3) s^(–1) M^(–1)。进一步探究金属离子对PtPAL酶活性的影响表明, Ba~(2+)显著增强了PtPAL酶活性, Mn~(2+)、Co^(2+)、Cu^(2+)及Zn^(2+)抑制了PtPAL酶活性。本研究为进一步研究PtPAL的功能特点及半夏苯丙胺类生物碱代谢途径奠定基础。

关键词：半夏麻黄碱苯丙氨酸解氨酶基因克隆表达分析酶动力学分析

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Preparation and study of novel mid-to-low-temperature phase-change molten salts

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Science China Technological Sciences 2025年

作者： Chenxing REN Yifan WANG xin HE Chenghang zheng Xiang GAO State Key Laboratory of Clean Energy Utilization Zhejiang University Institute of Carbon Neutrality Zhejiang University Baima Lake Laboratory Zhejiang University

Molten salts is a promising medium for heat storage and heat transfer due to their advantages of low cost, low steam pressure, high energy storage density and wide temperature range. In this paper, a new phase change mixture of molten salts with KNO3, NaNO3, ZnCl2, NaF, Na2CO3, NaCl, and MgO as materials has been prepared through a plenty of experiments. The experimental results show that the melting point of some molten salts can be reduced to 202.9°C, and the decomposition temperature can reach 701.3°C. In addition, its thermophysical properties, including specific heat, viscosity and thermal stability, were measured and analyzed. The average specific heat of some molten salts is as high as 2.53 J/（g K）, and the average thermal conductivity is as high as 0.77 W/（m K）. In the 4-day short-term thermal stability test, the fluctuation of each parameter is minimal, and the overall thermal physical property is relatively stable. Compared with the traditional phase change molten salt, the new hybrid molten salt has a significantly lower melting point, a further improvement in the decomposition temperature, specific heat and other comprehensive thermophysical properties, and a better overall economy, which has important application value in heat transfer and energy storage.

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Resting-state brain network remodeling after different nerve reconstruction surgeries:a functional magnetic resonance imaging study in brachial plexus injury rats

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Neural Regeneration Research 2025年第5期20卷 1495-1504页

作者： Yunting Xiang Xiangxin xing Xuyun Hua Yuwen Zhang xin Xue Jiajia Wu Mouxiong zheng He Wang Jianguang Xu School of Rehabilitation Science Shanghai University of Traditional Chinese MedicineShanghaiChina Engineering Research Center of Traditional Chinese Medicine Intelligent Rehabilitation Ministry of EducationShanghaiChina Department of Rehabilitation Medicine Yueyang Hospital of Integrated Traditional Chinese and Western MedicineShanghai University of Traditional Chinese MedicineShanghaiChina Department of Traumatology and Orthopedics Yueyang Hospital of Integrated Traditional Chinese and Western MedicineShanghai University of Traditional Chinese MedicineShanghaiChina Institute of Science and Technology for Brain-Inspired Intelligence Fudan UniversityShanghaiChina Key Laboratory of Computational Neuroscience and Brain-Inspired Intelligence(Fudan University) Ministry of EducationShanghaiChina Human Phenome Institute Fudan UniversityShanghaiChina

Distinct brain remodeling has been found after different nerve reconstruction strategies,including motor representation of the affected ***,differences among reconstruction strategies at the brain network level have not been *** study aimed to explore intranetwork changes related to altered peripheral neural pathways after different nerve reconstruction surgeries,including nerve repair,endto-end nerve transfer,and end-to-side nerve ***–Dawley rats underwent complete left brachial plexus transection and were divided into four equal groups of eight:no nerve repair,grafted nerve repair,phrenic nerve end-to-end transfer,and end-to-side transfer with a graft sutured to the anterior upper ***-state brain functional magnetic resonance imaging was obtained 7 months after *** independent component analysis algorithm was utilized to identify group-level network components of interest and extract resting-state functional connectivity values of each voxel within the *** in intra-network resting-state functional connectivity were compared among the *** muscle reinnervation was assessed by behavioral observation(elbow flexion)and *** results showed that alterations in the sensorimotor and interoception networks were mostly related to changes in the peripheral neural *** repair was related to enhanced connectivity within the sensorimotor network,while end-to-side nerve transfer might be more beneficial for restoring control over the affected limb by the original motor *** thalamic-cortical pathway was enhanced within the interoception network after nerve repair and end-to-end nerve *** areas related to cognition and emotion were enhanced after end-to-side nerve *** study revealed important brain networks related to different nerve *** networks may be potential targets for enhancing motor recovery.

关键词： brain functional networks end-to-end nerve transfer end-to-side nerve transfer independent component analysis nerve repair peripheral plexus injury resting-state functional connectivity

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