检索结果-南通市图书馆

Structure, spin reorientation and Mssbauer effect studies of Tb0.3.y0.7(Fe1-xAlx)1.95 alloys

Science china(Physics,Mechanics & Astronomy) 2006年第2期Mechanics & Astronomy) .卷 149-157页

作者： ZHENG Xiaoping1,2,4, ZHANG Peifeng1,3. FAN Duowang1, LI Fashen3.& HAO Yuan41. key laboratory of Opto-Electronic Technology and Intelligent Control, ministry of education, {3. Jiaotong university, {3. 73.070, china 2. Institute of Electronic Information Science and Technology,{3. Teachers College, {3. 73.070, china 3. key laboratory for magnetism and magnetic materials, ministry of education, lanzhou university,{13., china 4. State key Lab. of Advanced Non-Ferrous materials, Gansu Province, lanzhou university of Technology, {3. 73.050, china

The effect of Al substitution for Fe on crystal structure, magnetostriction and spontaneous magnetostriction, anisotropy and spin reorientation of a series of polycrys-talline Tb0.3.y0.7(Fe1?xAlx)1.95 alloys (x = 0, 0.05, 0.1, 0.15, 0.20, 0.25, 0.3., 0.3.) at room temperature and 77 K was investigated systematically. It was found that the primary phase of Tb0.3.y0.7(Fe1?xAlx)1.95 is the MgCu2-type cubic Laves phase structure when x 3.y0.7(Fe1?xAlx)1.95 increases approximately and monotonically with the increase of x. The substitution of Al leads to the fact that the magnetostriction λ inceases slightly in a low magnetic field (H ≤ 40 kA/m), but decreases sharply and is easily close to saturation in a high applied field as x increases, showing that a small amount of Al substitution is beneficial to a decrease in the magnetocrystalline anisotropy. It was also found that the spontaneous magnetostriction λ111 decreases greatly with x in-creasing. The analysis of the M?ssbauer spectra indicated that the easy magnetization direction in the {110} plane deviates slightly from the main axis of symmetry with the changes of composition and temperature, namely spin reorientation. A small amount of non-magnetic phase exists for x = 0.15 in Tb0.3.y0.7(Fe1?xAlx)1.95 alloys and the alloys be-come paramagnetic for x > 0.15 at room temperture, but at 77 K the alloys still remain magnetic phase even for x = 0.2. At room temperature and 77 K, the hyperfine field de-creases and the isomer shifts increase with Al concentration increasing.

关键词： magnetostriction cubic Laves phase spin reorientation M?ssbauer.

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

magnetic properties and tunneling magnetoresistance in FeCo-SiO_2 granular films

引用

Chinese Science Bulletin 2001年第9期46卷 734-737页

作者： XI Li, ZHANG Zongzhi, CHI Junhong, LI Chengxian & GE Shihuikey laboratory for magnetism and {3. materials of the ministry of education, lanzhou university, lanzhou 730000, china key laboratory for magnetism and {3. materials of the ministry of education Lanzhou University Lanzhou China

Fefv(SiO2)1-fv granular films were fabricated by rf sputtering (fv represents the Fe volume fraction). The mi-crostructure, magnetic properties as well as the tunneling magnetoresistance effect (TMR) were systematically studied. It was found that the maximum TMR ratio is about -3.3. at fv = 0.3.. Under the same condition, a series of (Fe100-x Cox)0.3.(SiO2)0.67 were prepared. TMR value reaches -4.5% at x=53. while the microstructure of the film still keeps as that of Fe0.3.(SiO2)0.67. The higher TMR ratio is contributed to the elevating of the spin polarization of particles. This is consistent with Inoue’s theory.

关键词： tunneling magnetoresistance granular films.

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Numerical study on short-circuit current of single layer organic solar cells with Schottkey contacts

引用

Science china(Technological Sciences) 2010年第4期53卷 1023-1027页

作者： MA ChaoZhu1,MENG WeiMin2,PENG YingQuan1,2,WANG RunSheng1,LI RongHua1,XIE HongWei1,WANG Ying1 & YE ZaoChen1 1 Institute of Microelectronics of School of Physical Science and Technology,lanzhou university,lanzhou {3.,china 2 key laboratory for magnetism and magnetic materials of the ministry of education,lanzhou university,lanzhou {3.,china 1. Institute of Microelectronics of School of Physical Science and Technology Lanzhou University Lanzhou 730000 China2. Key Laboratory for Magnetism and Magnetic Materials of the Ministry of Education Lanzhou University Lanzhou 730000 China

The influence of the cathode work function,carriers mobilities and temperature on the short-circuit current of single layer organic solar cells with Schottkey contacts was numerically studied,and the quantitative dependences of the short-circuit current on these quantities were *** results provide the theoretical foundation for experimental study of single layer organic solar cells with Schottkey contacts.

关键词： cathode work function carrier mobility temperature short-circuit current

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Soft magnetic properties of (Ni_(50)Fe_(50)) SiO_2 granular thin films for high frequency application

引用

Rare Metals 2006年第z1期25卷 650-654页

作者： YANG Xiaolin GE Shihui RUAN Chengli College of Physics and Electronic Science University of Electronic Science and Technology of China Chengdu 610054 China Key Laboratory for Magnetism and Magnetic Materials of Ministry of EducationLanzhou University Lanzhou 730000 China College of Physics and Electronic Science University of Electronic Science and Technology of China Chengdu 610054 China

A series of (Ni50Fe50)x(SiO2)(1-x) films with different volume fraction x was fabricated by magnetron co-sputtering technique. The microstructure, magnetic and electrical properties were investigated systematically by using X-ray diffraction, transmission electronic microscope, vibrating sample magnetometer and the traditional four point measurement method of resistivity. The results show that the samples consist of nano-scaled Ni50Fe50 metallic particles with fcc structure uniformly embedded in amorphous insulating SiO2 matrix, and the particle size decreases with the decrease of x. The rapid change of coercivity with x is observed, and a minimum value 160 A·m-1 of Hc was obtained for the sample of x=0.83.with film thickness of 180 nm, which can be contributed to the exchange coupling between nano-scaled Ni50Fe50 particles. At the frequency lower than 1 GHz, the real part μ′ of complex permeability keeps about 110 and the image part μ″ is less than 15. Besides, this film exhibits high resistivity ρ=263.μΩ·cm, high saturation magnetization 4πMs=1.25 T, high in-plane magnetic anisotropy field Hk=6.3. kA·m-1, and the ferromagnetic resonance (FMR) frequency is estimated to be 2.8 GHz. Therefore, this film can be used in high frequency devices operating over 2 GHz.

关键词： thin films nanostructure magnetic properties

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Recent Advances in Asymmetric Structural Composites for Excellent Electromagnetic Interference Shielding: A Review

引用

Chinese Journal of Polymer Science 2024年第6期42卷 693-710页

作者： Ying zhou Bai Xue lan Xie Chang-Mei Wu Qiang Zheng Department of Polymer materials and Engineering College of Materials and Metallurgy Guizhou University National Engineering Research Center for Compounding and Modification of Polymer materials National and Local Joint Engineering Research Center for Functional Polymer Membrane Materials and Membrane Processes State key laboratory of Public Big Data Guizhou University Department of Polymer Science and Engineering Zhejiang University

Since electromagnetic pollution is detrimental to human health and the environment, numerous efforts have been successively made to achieve excellent electromagnetic interference shielding effectiveness(EMI SE) via designing the hierarchical structures for electromagnetic interference(EMI) shielding polymer composites. Among the plentiful structures, the asymmetric structures are currently a hot spot, principally categorizing into multi-layered, porous, fibrous, and segregated asymmetric structures, which endows the high EMI shielding performance for polymer composites incorporated with magnetic, conductive, and/or dielectric micro/nano-fillers, due to the “absorption-reflection-reabsorption” shielding mechanism. Therefore, this review provides the retrospection and summary of the efforts with respect to abundant asymmetric structures and multifunctional micro/nano-fillers for enhancing EMI shielding properties, which is conducive to the booming development of polymeric EMI shielding materials for the promising prospect in modern electronics and 5-generation(5G) technology.

关键词： Asymmetric structure Micro/nano functional filler Polymer composite Electromagnetic interference shielding

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Discovery of a 1.0 Ma Yellow River terrace and redating of the fourth Yellow River terrace in lanzhou area

引用

Progress in Natural Science:materials International 2007年第2期17卷 197-205页

作者： PAN Baotian , SU Huai, HU Chunsheng, HU Xiaofei, zhou Tian and LI Jijun (key laboratory of Western{3.’s Environmental Systems, ministry of education, and Department of Geography, lanzhou university, lanzhou 730000,{3.) [a]ministry of Eduction Key Laboratory of Western China's Environmental Systems [b]Department of Geography Lanzhou University Lanzhou China

Based on the aeolian loess sequence-stratigraphic division and paleomagnetic datings on terraces, we found that an undiscovered terrace with the age of 1.0 Ma BP lies between the Dunwashan terrace and Wuyishan terrace. This terrace recorded an intensive Yellow River incision event during that period. Results of paleomagnetic dating and optically stimulated luminescence (OSL) dating of the Wuyishan loess section and Zaoshugou loess section on the fourth Yellow River terrace (T4) show that the age of the fourth Yellow River terrace in lanzhou area is 0.86 Ma BP rather than the previously believed 0. 6 Ma BP. This result answers a long-term question in the ge-omorphology community of whether there exists a 0. 8 Ma terrace in lanzhou area. The discovery of the 1. 0 Ma Yellow River terrace and redating of the age of 0.6 Ma terrace in lanzhou area provide new insights into further research on the evolution of Yellow River.

关键词： lanzhou area Yellow River terrace dating.

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Electromagnetic wave absorption performance and rheological behavior of rubber composites with low mass filling rate carbon nanofiber aerogel

引用

Journal of Materiomics 2024年第4期10卷 928-936页

作者： Zhiyi Zhang Bicheng zhou lan Jia Wenwen Yu Qiang Zheng College of materials Science and Engineering Taiyuan University of TechnologyTaiyuan030024China Shanxi-Zheda Institute of Advanced materials and Chemical Engineering Taiyuan030000China rd Research Institute of china Electronics Technology Group Corporation Taiyuan030032China Department of Polymer Science&Engineering Zhejiang UniversityHangzhou310027China

With the development of electronic information science and technology,electromagnetic information security and electromagnetic pollution become more and more *** wave absorption(EMWA)rubber based on the absorbent of carbon with low density and good corrosion resistance is a kind of good EMWA materials for solving electromagnetic information security and electromagnetic *** this article,three-dimensional network structure carbon nanofiber aerogels(3.NSCAs)are prepared by vacuum annealing of three-dimensional network structure agarose/zinc acetate obtained by freeze-drying of agarose/zinc acetate *** EMWA rubber composites with 2.2%(in mass)3.NSCAs have almost the same density as silicone rubber(PDMS),and the dispersity of 3.NSCAs in PDMS is studied by rheological *** effective absorption bandwidth(EAB,frequency for reflection loss3.5 *** PDMS/C-1000 with the thickness of 3.5 mm has an EAB up to 4.8 *** cross section(RCS)reduction of PDMS/C-800 can achieve 20 dB⋅m2 at the frequency of 6 GHz.

关键词： Electromagnetic wave absorption Rubber composite Carbon aerogel Rheological behavior Power loss density

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Effects of different pack aluminizing fillers on the aluminide coatings of Ti-6Al-4V alloy and their high-temperature oxidation behaviors

引用

Rare Metals 2007年第S1期26卷 306-312页

作者： zhou Wei,ZHAO Yuguang,and MEI Xuelian key laboratory of Automobile {3. of ministry of education,Department of {3. Science and Engineering,Jilin university,Changchun 13.025,china Jilin Univ Dept Mat Sci & Engn Key Lab Automobile Mat Minist Educ Changchun 130025 Peoples R China

The aluminide coating process of Ti-6Al-4V alloys with different fillers(100wt.% Al_2O_3.50wt% Y_2O_3.50wt.% Al_2O_3.and 100wt.% Y_2O_3. for improvement of the oxidation resistance were *** results show that the filler does not only participate in the aluminizing process,but also has much effect on the coating *** XRD analysis reveals that the aluminide coating with filler Al_2O_3.is predominant with TiAl_3.and TiAl phases;while the aluminide coatings with filler Y_2O_3.Al_2O_3.are predominant with Ti_3.l *** oxidation kinetics shows that different fillers affect greatly the oxidation resistance of aluminide coating,and the oxidation resistance of aluminized specimens with pack aluminizing filler Al_2O_3.are about 5-8 times than that of the aluminized specimens with other pack aluminizing fillers.

关键词： Ti-6Al-4V alloy aluminide coating fillers oxidation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Study on preparation,characterization and application of mixed-colorants thermochromic microcapsules

引用

Particuology 2024年第5期88卷 89-97页

作者： lan zhou Jingpeng Ye Qinze Cai Guojin Liu Mehran Dadgar Guocheng Zhu Guoqing Zhang College of Textile Science and Engineering (International Institute of Silk) Zhejiang Sci-Tech UniversityHangzhou310018China School of materials Science& Engineering Zhejiang Sci-Tech UniversityHangzhou310018China Department of Textile University of NeyshaburAdib BoulevardKhorasan Razavi ProvinceIran Zhejiang Charming Dyeing and Finishing Co. LtdJiaxing314500China Zhejiang Provincial Innovation Center of Advanced Textile Technology Shaoxing312000China

In order to expand the color-change range and make the discoloration temperature suitable for the daily textiles,a new formulation of mixed-colorants thermochromic core material is designed,in which crystal violet lactone(CVL)is the basic color former,bisphenol A(BPA)is the developer,especially the solvent-based dye and dodecyl dedecanoate are used as the extended dye and the solvent,*** electron microscope(SEM),differential scanning calorimeter(DSC)and thermogravimetric analyzer(TGA)were applied to study the morphology,encapsulation rate,non-isothermal crystallization behavior and thermal stability of the mixed-colorant thermochromic microcapsules(MCTMs)prepared by in-situ *** results show that MCTMs have good sphericity,uniform particle size,good thermal stability and the encapsulation rate can reach 86.73..Under the non-isothermal conditions,the encapsulation of formaldehyde-melamine resin wall material can slightly reduce the crystallization rate of the solvent,but does not affect the relative crystallinity,thermal properties and discoloration sensitivity of the core *** the variety of ambient temperatures in the range of 20–3.℃,the printed cotton fabrics with MCTMs could change color reversibly between different tones with good reliability and durability,and exhibit more gorgeous colors than the common thermochromic materials.

关键词： Thermochromic microcapsule Color-change range Phase-change material Crystallization behavior

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Numerical Simulation of the Mechanical Stirring Process in a Tannin-Based Foaming Precursor Resin

引用

Fluid Dynamics & materials Processing 2024年第10期20卷 2219-2234页

作者： lan Huang Wenbin Yuan Hisham Essawy Xiaojian zhou Xinyi Chen Yunnan Provincial key laboratory of Wood Adhesives and Glued Products Southwest Forestry UniversityKunming650224China Department of Polymers and Pigments National Research CentreCairo12622Egypt key laboratory for Forest Resources Conservation and Utilization in the Southwest Mountains of china Southwest Forestry UniversityKunming650224China

Tannin foam is a new functional *** can be widely applied to the automobile industry,construction industry,and packaging industry due to its wide range of raw materials,renewable,easily degraded,low cost and almost no *** tannin foam is a very complex process that includes high temperature,two phases,mechanical agitation,and phase *** investigate the influence of the stirring velocity and paddle shape,simulation was calculated by making use of the volume of fluid(VOF)method and multiple reference frame(MRF)method in a three-dimensional flow field of tannin-based foaming precursor *** gas holdup and velocity magnitude were analysed with various conditions of mechanical velocities and paddle shape in the stirring flow *** result shows the higher the velocity,the greater the disturbance and paddle shape between the eggbeater and the Rushton turbine,obviously the paddle shape of the eggbeater with a wider range of agitation,which can entrap more air into the tannin-based foaming precursor resin in a short *** when the speed is 1500 rpm,the flow field of the Rushton turbine comes out of a ditch,which decreases the efficiency of mass transfer;there is less air to mix into the tannin-based foaming precursor resin,which causes *** the same time,the eggbeater shows the marvelous capability of hybrid as it has two vortexes and multiple cycles that make a difference from the Rushton turbine,which has only one vortex and two upper and lower loops;the structure makes the flow field more stable allowed evenness of flow field tannin-based foaming precursor *** results reveal that it is beneficial for tannin-based foaming precursor resin to use an eggbeater with a speed of 1500 rpm to reduce the consumption of resources while obtaining a uniform flow field.

关键词： Tannin-based foaming precursor resin mechanical agitation numerical simulation volume of fluid(VOF) multiple reference frame(MRF)

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：