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Determination of thermal conductivity of magnesium-alloys

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Journal of Central South University of Technology 2001年第1期8卷 60-63页

作者： ZHOU jie min 1,yang Ying 1,Magne Lamvik 2,WANG Gang 1 (1.Department of Applied Physics and Heat Engineering, Central South University, Changsha 410083, China 2.Norwegian University of Science and Technology) 1. Department of Applied Physics and Heat Engineering Central South University 410083 Changsha China 2. Norwegian University of Science and Technology China

An indirect method, Angstroms method was adopted and an instrument was designed to determine the thermal conductivity of magnesium metal and alloys. Angstroms method is an axial periodic heat flow technique by which the thermal diffusivity can be measured directly. Then thermal conductivity can be obtained with relation to thermal diffusivity. Compared with the recommended data from the literature the fitted values of the thermal diffiusivity correspond with 3%, and the credible probability of the thermal conductivity in the range of 0 450 ℃ is about 95%. The method is applicable in the given temperature range.

关键词： angstroms method thermal conductivity thermal diffusivity magnesium alloy

Antifeedant and Antiviral Diterpenoids from the Fresh Roots of Euphorbia jolkinii

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Natural Products and Bioprospecting 2014年第2期4卷 91-100页

作者： Chun-Shuai Huang Shi-Hong Luo Yao-Lan Li Chun-Huan Li Juan Hua Yan Liu Shu-Xi Jing Ying Wang min-jie yang Sheng-Hong Li State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China Graduate University of Chinese Academy of Sciences Beijing 100049China Institute of Traditional Chinese Medicine and Natural Products Jinan UniversityGuangzhou 510632China

The perennial herbaceous plant Euphorbia jolkinii(Euphorbiaceae)is a noxious weed widely distributed in the grasslands of northwestern Yunnan and has greatly threatened the local *** investigation on the fresh roots of *** afforded six new diterpenoids 1,2,4–6,and 8,together with fifteen known *** structures were elucidated on the basis of 1D and 2D NMR and other spectroscopic ***,lathyrane,abietane,and ent-kaurane diterpenoids were reported from this plant for the first *** compounds were evaluated for their antifeedant and anti-RSV(respiratory syncytial virus)*** 2 and ingenol(3)exhibited moderate antifeedant activity against a generalist insect herbivore,Spodoptera exigua,with EC50 values of 17.88 and 17.71 lg/cm2 *** 19 showed significant anti-RSV activity,with 50%inhibition(IC50)value of 10.0 lM and selective index of *** 1 and 2 were less active against RSV virus,both with IC50 value of 25 lM,and with selective indices of 1.0 and 3.2 *** findings provided new evidence for the biological functions and utilization of the diversified diterpenoid metabolites in the roots of this rich but harmful plant.

关键词： Euphorbia jolkinii Diterpenoids Antifeedant activity Antiviral activity

Ideal Bi‑Based Hybrid Anode Material for Ultrafast Charging of Sodium‑Ion Batteries at Extremely Low Temperatures

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Nano-Micro Letters 2025年第3期17卷 152-167页

作者： jie Bai Jian Hui Jia Yu Wang Chun Cheng yang Qing Jiang Key Laboratory of Automobile Materials(Jilin University) Ministry of EducationSchool of Materials Science and EngineeringJilin UniversityChangchun 130022People’s Republic of China

Sodium-ion batteries have emerged as competitive substitutes for low-temperature applications due to severe capacity loss and safety concerns of lithium-ion batteries at−20°C or ***,the key capability of ultrafast charging at ultralow temperature for SIBs is rarely ***,a hybrid of Bi nanoparticles embedded in carbon nanorods is demonstrated as an ideal material to address this issue,which is synthesized via a high temperature shock *** a hybrid shows an unprecedented rate performance(237.9 mAh g^(−1)at 2 A g^(−1))at−60℃,outperforming all reported SIB anode *** with a Na_(3)V_(2)(PO_(4))_(3)cathode,the energy density of the full cell can reach to 181.9 Wh kg^(−1)at−40°*** on this work,a novel strategy of high-rate activation is proposed to enhance performances of Bi-based materials in cryogenic conditions by creating new active sites for interfacial reaction under large current.

关键词： Bi nanoparticles High temperature shock High-rate activation Ultrafast charging Low-temperature sodium-ion batteries

Effects of the extrusion parameters on microstructure,texture and room temperature mechanical properties of extruded Mg-2.49Nd-1.82Gd-0.2Zn-0.2Zr alloy

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International Journal of minerals,Metallurgy and Materials 2025年第1期32卷 136-146页

作者： Chenjin Zhang Guangyu yang Lei Xiao Zhiyong Kan Jing Guo Qiang Li Wanqi jie State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China College of Materials Science and Engineering Fuzhou UniversityFuzhou 350108China College of Chemistry and Environmental Science Qujing Normal UniversityQujing 655011China

Microstructure,texture,and mechanical properties of the extruded Mg-2.49Nd-1.82Gd-0.2Zn-0.2Zr alloy were investigated at different extrusion temperatures(260 and 320℃),extrusion ratios(10:1,15:1,and 30:1),and extrusion speeds(3 and 6 mm/s).The experimental results exhibited that the grain sizes after extrusion were much finer than that of the homogenized alloy,and the second phase showed streamline distribution along the extrusion direction(ED).With extrusion temperature increased from 260 to 320℃,the microstructure,texture,and mechanical properties of alloys changed *** dynamic recrystallization(DRX)degree and grain sizes enhanced as the extrusion ratio increased from 10:1 to 30:1,and the strength gradually decreased but elongation(EL)*** the extrusion speed increased from 3 to 6 mm/s,the grain sizes and DRX degree increased significantly,and the samples presented the typical-rare-earth(RE)*** alloy extruded at 260℃ with extrusion ratio of 10:1 and extrusion speed of 3 mm/s showed the tensile yield strength(TYS)of 213 MPa and EL of 30.6%.After quantitatively analyzing the contribution of strengthening mechanisms,it was found that the grain boundary strengthening and dislocation strengthening played major roles among strengthening *** results provide some guidelines for enlarging the industrial application of extruded Mg-RE alloy.

关键词： Mg-rare earth alloys extrusion temperature extrusion ratio extrusion speed strengthening mechanisms

The Internet of Things under Federated Learning:A Review of the Latest Advances and Applications

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Computers, Materials & Continua 2025年第1期82卷 1-39页

作者： Jinlong Wang Zhenyu Liu Xingtao yang min Li Zhihan Lyu School of Information and Control Engineering Qingdao University of TechnologyQingdao260043China Anhui Province Key Laboratory of Intelligent Building&Building Energy Saving Anhui Jianzhu UniversityHefei230000China Department of Game Design Uppsala UniversityUppsala75310Sweden

With the rapid development of artificial intelligence,the Internet of Things(IoT)can deploy various machine learning algorithms for network and application *** the IoT environment,many sensors and devices generatemassive data,but data security and privacy protection have become a serious *** learning(FL)can achieve many intelligent IoT applications by training models on local devices and allowing AI training on distributed IoT devices without data *** review aims to deeply explore the combination of FL and the IoT,and analyze the application of federated learning in the IoT from the aspects of security and privacy *** this paper,we first describe the potential advantages of FL and the challenges faced by current IoT systems in the fields of network burden and privacy ***,we focus on exploring and analyzing the advantages of the combination of FL on the Internet,including privacy security,attack detection,efficient communication of the IoT,and enhanced learning *** also list various application scenarios of FL on the ***,we propose several open research challenges and possible solutions.

关键词： Federated learning Internet of Things sensors machine learning privacy security

Heat transfer in high density electronics packaging

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Journal of Central South University of Technology 2001年第4期8卷 278-282页

作者： ZHOU jie min 1, yang Ying 1, DENG Sheng xiang 1, YI Zheng ming 1, WANG Xi tao 2, CHEN Liu 2, Johan Liu 2 (1.Department of Applied Physics and Heat Engineering, Central South University, Changsha 410083, China 2.Department of Production En 1. Department of Applied Physics and Heat Engineering Central South University 410083 Changsha China 2. Department of Production Engineering Chalmers University of Technology SE-41296 G?teborg Sweden

In order to get an insight into the thermal characteristic and to evaluate the thermal reliability of the "System in Packaging"(SIP), a new solution of electronics packaging, a heat transfer model of SIP was developed to predict the heat dissipation capacity and to investigate the effect of different factors on the tempe rature distribution in the electronics. The affecting parameters under consideration include the thermophysical properties of the substrates, the coefficient of convection heat transfer, the thickness of the chip, and the density of power dissipation. ALGOR, a kind of finite element analysis software,was used to do the model simulation. Based on the simulation and analysis of the heat conduction and convection resistance, criteria for the thermal design were established and possible measurement for enhancing power dissipation was provided. The results show that the heat transfer model provides a new and effective way to the thermal design and thermal analysis of SIP and to the mechanical analysis for the further investigation of SIP.

关键词： electronics packaging thermal reliability heat transfer

Gamma-glutamyl transferase 5 overexpression in cerebrovascular endothelial cells improves brain pathology,cognition,and behavior in APP/PS1 mice

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Neural Regeneration Research 2025年第2期20卷 533-547页

作者： Yanli Zhang Tian Li jie Miao Zhina Zhang mingxuan yang Zhuoran Wang Bo yang Jiawei Zhang Haiting Li Qiang Su Junhong Guo Department of Neurology First Hospital of Shanxi Medical UniversityTaiyuanShanxi ProvinceChina Department of Neurology Sixth Hospital of Shanxi Medical University(General Hospital of Tisco)TaiyuanShanxi ProvinceChina Department of Physiology Key Laboratory of Cellular PhysiologyMinistry of EducationShanxi Medical UniversityTaiyuanShanxi ProvinceChina Department of Hernia and Abdominal Wall Surgery Shanxi Bethune HospitalShanxi Academy of Medical SciencesTongji Shanxi HospitalThird Hospital of Shanxi Medical UniversityTaiyuanShanxi ProvinceChina Department of Laboratory Medicine of Fenyang College Shanxi Medical UniversityFenyangShanxi ProvinceChina

In patients with Alzheimer’s disease,gamma-glutamyl transferase 5(GGT5)expression has been observed to be downregulated in cerebrovascular endothelial ***,the functional role of GGT5 in the development of Alzheimer’s disease remains *** study aimed to explore the effect of GGT5 on cognitive function and brain pathology in an APP/PS1 mouse model of Alzheimer’s disease,as well as the underlying *** observed a significant reduction in GGT5 expression in two in vitro models of Alzheimer’s disease(Aβ_(1-42)-treated hCMEC/D3 and bEnd.3 cells),as well as in the APP/PS1 mouse ***,injection of APP/PS1 mice with an adeno-associated virus encoding GGT5 enhanced hippocampal synaptic plasticity and mitigated cognitive ***,increasing GGT5 expression in cerebrovascular endothelial cells reduced levels of both soluble and insoluble amyloid-βin the brains of APP/PS1 *** effect may be attributable to inhibition of the expression ofβ-site APP cleaving enzyme 1,which is mediated by nuclear factor-kappa *** findings demonstrate that GGT5 expression in cerebrovascular endothelial cells is inversely associated with Alzheimer’s disease pathogenesis,and that GGT5 upregulation mitigates cognitive deficits in APP/PS1 *** findings suggest that GGT5 expression in cerebrovascular endothelial cells is a potential therapeutic target and biomarker for Alzheimer’s disease.

关键词： Alzheimer’s disease amyloid-β APP/PS1 mice cerebrovascular endothelial cells cognitive deficits gamma-glutamyl transferase 5 neurovascular unit nuclear factor‐kappa B synaptic plasticity β-site APP cleaving enzyme 1

Hydration, Microstructure, and Properties of Sulphoaluminate Cement in Pure Water and Simulated Seawater

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 187-193页

作者： MA jie China Railway Design Corporation Tianjin 300250China

Paste and mortar specimens were prepared with sulfoaluminate cement(SAC),P⋅O 42.5 ordinary Portland cement(OPC),and standard sand,and mixed and cured with pure water and artificial seawater,*** mechanical properties of mortar specimens were *** and microstructure of paste specimens were also investigated using X-ray diffraction(XRD),scanning electron microscope(SEM),and 27Al nuclear magnetic resonance(NMR),*** results indicate that SAC mortar samples mixed and cured by seawater have faster strength growth before 28 d and higher compressive strength than OPC mortar *** to curing in deionized water,the hydration products of SAC are somewhat coarser when cured in simulated *** evolution of aluminum phase hydration products during the hydration process of SAC mixed and cured in simulated seawater is quite different from that of *** 3 to 28 d,the content of each aluminum phase hydration product in SAC paste cured in simulated seawater changed little,while that in OPC paste changed significantly;for example,from 7 to 28 d,the content of ettringite(AFt)in OPC paste increased *** type of AFt formed loosely,harming the mortar's microstructure.

关键词： sulfoaluminate cement seawater mixing and curing 27Al NMR AFt

Identification of a dual functional betulinic acid analog for the treatment of osteoarthritis by phenotypic screening

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Science China Life Sciences 2025年第1期 300-302页

作者： Ze-min Lin Mai Xiang Wen-Hui Wei Shu-Hui Fan Li Chen jie Wang Xiao-Qian yang Chun-Hao yang Shi-Jun He Jian-Ping Zuo Laboratory of Immunopharmacology State Key Laboratory of Drug ResearchShanghai Institute of Materia MedicaChinese Academy of Sciences School of Pharmacy University of Chinese Academy of Sciences School of Pharmacy Nanjing University of Chinese Medicine State Key Laboratory of Drug Research Department of Medicinal ChemistryShanghai Institute of Materia MedicaChinese Academy of Sciences Innovation Research Institute of Traditional Chinese Medicine Shanghai University of Traditional Chinese Medicine Experiment Center for Science and Technology Shanghai University of Traditional Chinese Medicine

Dear Editor, Phenotypic drug discovery, which observes compound effects on physiology,has given way to targeting specific molecules, but has revived by using modern methods to find drugs based on therapeutic outcomes in disease models(Vincent et al., 2022). Osteoarthritis(OA) is a prevalent chronic joint disorder, primarily affecting knee joints, with osteoclast activation due to low-grade inflammation resulting in increased bone resorption and structural changes in the joint(Katz et al.,2021).

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