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Particuology 2016年第1期14卷 159-163页

作者： xi zhou Jian Mao Zhen Qiao College of Materials Science and Engineering Sichuan University No. 24 South Section 1 Yihuan Road. Chengdu 610064 Sichuan China

A copper coating was deposited by electroless plating on the surfaces of urea-formaldehyde microcap- sules containing paraffin （UFP） particles. This composite microcapsule structure had low infrared OR） emissivity and maintained a constant temperature, and could be used in IR stealth applications. The eiectroless copper layer formation and its micro-appearance, and the effect of the copper layer on the IR emissivity and thermal properties of the composite microcapsules were investigated. The IR emissivity of the composite microcapsules at wavelengths of 1-14 μm gradually decreased with increasing copper mass on the surface. After formation of an integrated copper layer, the rate of IR emissivity decrease was lower. This is because the copper coating improves the surface conductivity of the UFP; a high conductivity results in high reflectivity, which leads to a decrease in IR emissivity. The lowest IR emissivity achieved was 0.68. The phase-change enthalpy of the composite microcapsules decreased with increasing amount of copper coated on the surface because of the high density of copper. When the mass increase of the UFP after electroless copper plating was about 300%, the composite microcapsules had low IR emissivity （about 0.8） and a high phase-change enthalpy （80J/g）.

关键词： Phase-change material Urea-formaldehyde microcapsules containing paraffin particle Electroless copper plating Low infrared emissivity Enthalpy

New Macrocyclic Diamide from Rauvolfia Yunnanensis Tsiang

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Chemical Research in Chinese Universities 2008年第3期24卷 303-305页

作者： GENG chang-an LIU xi-kui State Key Laboratory of Phytochemistry and Plant Resourses in West China Kunming Institute of Botany Chinese Academy of Sciences Kunming 650204 P. R. China Graduate School of the Chinese Academy of Sciences Beijing 100039 P. R. China

A new macrocyclic diamide, 22-membered macrocyclic diamide, named cyclodicaprylamide（2）, and five known compounds, bis（2-ethylhexyl） phthalate（1）, ethyl 3,4,5-trimethoxybenzoate（3）, ethyl 3,4,5-trimethoxycinnamate （4）, （＋）-syringaresinol（5）, loliolide（6）, were isolated from the roots of Rauvolfia yunnanensis Tsiang. Their structures were elucidated based on NMR, 2D NMR, and MS spectrum, respectively. They were obtained from it for the first time.

关键词： Rauvolfia yunnanensis Cyclodicaprylamide (+)-Syringaresinol Loliolide

Rheological and mechanical properties of aluminosilicious cementitious materials as refractory castable binders

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Journal of Iron and Steel Research International 2022年第7期29卷 1145-1151页

作者： Zhong-feng xia chang-hao Chen Wen-hao Chi zhou-fu Wang Hao Liu Yan Ma xi-tang Wang The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina

Metakaolin(MK)is an important refractory raw material,which has been used as a cementitious *** order to improve the bonding strength of MK,the composite cementitious materials were prepared by MK mixed with hydrat-able alumina(HA)and microsilica(MS),*** silane coupling agent(SCA)was introduced as a modifying *** rheological properties of MK-based composite cementitious slurries were *** mechanical properties of corundum castables bonded with the composite cementitious materials and calcium aluminate cement(CAC)were comparatively *** results show that SCA improves the rheological properties of MK-based composite cementitious *** slurry of MK–MS mixture flows in a plastic manner,while the slurry of MK–HA mixture presents pseudoplastic *** addition of SCA reduces the yield stress value of the MK–HA *** bonding strength of castables bonded with MK-based composite cementitious materials is lower than that of CAC bonding *** room temperature strength of MK–MS composite bonding castable remains the highest after being treated either at 1100 or 1550°C,and its high temperature modulus of rupture is higher than that of CAC bonding castables with microsilica added.

关键词： Metakaolin Hydratable alumina Microsilica Silane coupling agent Corundum castable Calcium aluminate cement

Spin Accumulation in a Rashba Nanoribbon

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Communications in Theoretical Physics 2009年第7期52卷 159-162页

作者： FU xi zhou Guang-Hui Department of Physics Hunan Normal University Changsha 410081 China Department of Electronics and Physics Hunan University of Science and Engineering Yongzhou 425100 China

We investigate theoretically the spin accumulation in a Rashba spin-orbit coupling (SOC) nanoribbon nonadiabatically connected to a normal *** the nanoribbon and conductor are described by a hard-wall confining *** the scattering matrix approach within the effective free-electron approximation,we have calculated the out-of-plane spin accumulation in the *** is found that the spin accumulation shifts toward the two edges of nanoribbon with the increasing of propagation ***,as the Rashba SOC strength increases the spin accumulation in the nanoribbon will be enhanced and this result may suggest us a simple method to control the spin accumulation of the system by Rashba SOC strength.

关键词： nanoribbon Rashba spin-orbit coupling spin accumlation

Persistent Spin Current in a Hard-Wall Confining Quantum Wire with Weak Dresselhaus Spin-Orbit Coupling

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Communications in Theoretical Physics 2009年第2期51卷 341-344页

作者： FU xi zhou Guang-Hui Department of Physics Hunan Normal University Changsha 410081 China Department of Electronics and Physics Hunan College of Science and Technology Yongzhou 425100 China

We investigate theoretically the spin current in a quantum wire with weak Dresselhaus spin-orbit coupling connected to two normal conductors. Both the quantum wire and conductors are described by a hard-wall confining potential. Using the electron wave-functions in the quantum wire and a new definition of spin current, we have calculated the elements of linear spin current density j^Ts,xi and j^Ts,yi（i=x, y, z）. We find that the elements j^Ts,xx and j^Ts,yy have a antisymmetrical relation and the element j^Ts,yz has the same amount levelas j^Ts,xx and j^Ts,yy. We also find a net linear spin current density, which has peaks at the center of quantum wire. The net linear spin current can induce a linear electric field, which may imply a way of spin current detection.

关键词： quantum wire Dresselhaus spin-orbit coupling spin current

Continuous bending and straightening technology of Q345c slab based on high-temperature creep deformation

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Journal of Iron and Steel Research International 2017年第6期24卷 595-600页

作者： Long Guo xing-zhong Zhang chang-xi Feng National Engineering Research Center for Equipment and Technology of Cold Strip Rolling Yanshan University Qinhuangdao 066004 Hebei China

A new continuous bending and straightening casting curve with the aim of full using of high-temperature creep deformation was proposed. The curvature of bending and straightening segment varies as sine law with arc length. The basic arc segment is shortened significantly so that the length of bending and straightening area can be extended and the time of creep behavior can be increased. The distance from so lidifying front in the slab was calculated at 1200 ℃ by finite element method. The maximum strain rate of new casting curve at different locations inside the slab is 6.39 × 10 ^-5 s ^-1 during the bending segment and it tends to be 3.70 × 10 ^-5 s ^-1 in the straightening segment. The minimum creep strain rate is 7.45× 10 ^-5 s ^-1 when the stress is 14 MPa at 1 200 ℃. The strain rate of new casting machine can be less than the mini mum creep strain rate. Thus, there is only creep deformation and no plastic deformation in the bending and straightening process of steel continuous casting. Deformation of slabs depending on creep behavior only comes true. It is helpful for the design of the new casting machine and improvement of old casting machine depending on high temperature creep property.

关键词： Steel continuous castingCreep strain rateStrain rateHigh-temperaturecreep behaviorContinuous bendingContinuous straightening

阿尔泰地区巴泽雷克文化马鞍毛毡贴花艺术研究

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丝绸 2025年第1期62卷 101-109页

作者：常艳西安外国语大学艺术遗产研究中心西安710128

针对阿尔泰地区巴泽雷克文化马鞍毛毡贴花艺术,文章采用文献分析、图像分析、类型与历史比较的研究方法,对遗存情况、贴花工艺、历史溯源及盛行的原因、文化信仰几个方面进行梳理和分析。归纳巴泽雷克文化马鞍毛毡及其贴花工艺的制作流... 详细信息

针对阿尔泰地区巴泽雷克文化马鞍毛毡贴花艺术,文章采用文献分析、图像分析、类型与历史比较的研究方法,对遗存情况、贴花工艺、历史溯源及盛行的原因、文化信仰几个方面进行梳理和分析。归纳巴泽雷克文化马鞍毛毡及其贴花工艺的制作流程,探讨其用色的工艺和风格。研究认为,这种艺术形式经历了从本土到融合外来艺术样式,再到新本土风格形成的几个发展阶段。其显著特色是多种材料的搭配使用、强烈的冷暖对比配色及独特的动物贴花装饰。同时,毛毡贴花艺术不仅作为生活物资,更是原始宗教信仰的载体。无论从工艺水准还是地域特色,都是同时期甚至更晚时期其他地域无法相比的,因此具有重要的史料价值和艺术价值。

关键词：阿尔泰巴泽雷克文化马鞍毛毡贴花艺术

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3D-FEM modeling of the microscopic stress field of forsterite aggregate under hydrostatic pressure:Significance of the crystal orientation

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Science China Earth Sciences 2014年第6期57卷 1192-1198页

作者： CHEN Yuxiang LIU xi zhou YongSheng The Key Laboratory of Orogenic Belts and Crustal Evolution MOE Peking University School of Earth and Space Sciences Peking University The State Key Laboratory of Earthquake Dynamics Institute of Geology Earthquake Administration

Three Dimensional Finite Element Method(3D-FEM)has been used to model the deviatoric stress field in a forsterite aggregate with a sandwich geometry:two forsterite cubes aligned in the same crystallographic orientation(the"breads")sandwich a third forsterite cube(the"filling"),which might have an identical or different crystallographic *** results show that there is no von Mises stress in the forsterite sandwich if the sandwiching and sandwiched forsterite cubes are aligned in the same crystallographic *** the crystallographic orientations are different,however,von Mises stress and heterogeneous stress distribution occur both along the boundary and in the forsterite *** the investigated P-T conditions(up to 6.4GPa and 500°C),the resulted deviatoric stress is much lower than the yield strength of forsterite,so that higher P,higher T,or other means to create higher deviatoric stress is necessary,in order to constrain the yielding behavior of forsterite.

关键词： 3D-FEM forsterite aggregate crystallographic orientation stress distribution

Mesenchymal stem cell-derived extracellular vesicles:A promising therapeutic strategy in diabetic osteoporosis

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World Journal of Diabetes 2024年第12期15卷 2399-2403页

作者： Ya-Jing Yang xi-Er Chen Xu-chang zhou Feng-xia Liang Department of Acupuncture and Moxibustion Hubei University of Chinese MedicineWuhan 430065Hubei ProvinceChina College of Sports Medicine Wuhan Sports UniversityWuhan 430079Hubei ProvinceChina School of Sport Medicine and Rehabilitation Beijing Sport UniversityBeijing 100084China Preventive Treatment of Acupuncture and Moxibustion of Hubei Provincial Collaborative Innovation Center College of Acupuncture-Moxibustion and Orthopaedics of Hubei University of Chinese MedicineWuhan 430065Hubei ProvinceChina

Diabetic osteoporosis(DOP)is a serious complication of diabetes *** is urgent to explore efficient clinical treatment strategies for *** has been found that mesenchymal stem cell-derived extracellular vesicles(MSC-EVs),as an emerging cell-free therapy,show great potential in DOP ***-EVs can effectively promote bone formation,inhibit bone resorption,and modulate the inflammatory microenvironment by delivering cargoes of microRNAs,long non-coding RNAs,and proteins to target cells,thereby ameliorating bone loss in ***,there are limited reports on the treatment of DOP with *** evoke more attention to this potential strategy,this article summarised the extant literature on MSC-EVs for DOP to provide new directions for further research and to promote the application of MSC-EVs in the clinical management of DOP.

关键词： Bone marrow mesenchymal stem cells Adipose-derived mesenchymal stem cells extracellular vesicles MicroRNAs Long non-coding RNAs Diabetic osteoporosis

An accelerated direct demodulation method for image reconstruction using spherical data from the hard X-ray modulation telescope

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Research in Astronomy and Astrophysics 2013年第8期13卷 991-1012页

作者： Zhuo-xi Huo Jian-Feng zhou Department of Engineering Physics and Center for Astrophysics Tsinghua University Key Laboratory of Particle & Radiation Imaging (Tsinghua University) Ministry of Education Key Laboratory of High Energy Radiation Imaging Fundamental Science for National Defense

The hard X-ray modulation telescope （HXMT） mission is mainly devoted to performing an all-sky survey at 1- 250 keV with both high sensitivity and high spatial resolution. The observed data reduction as well as the image reconstruction for HXMT can be achieved by using the direct demodulation method （DDM）. However the original DDM is too computationally expensive for multi-dimensional data with high resolution to be employed for HXMT data. We propose an accelerated direct demodulation method especially adapted for data from HXMT. Simulations are also presented to demonstrate this method.

关键词： methods data analysis methods numerical techniques image processing instrumentation high angular resolution