检索结果-内蒙古大学图书馆

International Conference on Applied Superconductivity and Electromagnetic Devices, ASEMD

作者： Wu Ming Chen Xu Chuan Jiang Mustafa Yavuz Shiro Kambe School of Materials Science and Engineering University of New South Wales Sydney NSW Australia Waterloo Institute for Nanotechnology University of Waterloo Waterloo ONT Canada Cankaya University Ankara Turkey Human Sensing Program Graduate School of Science and Engineering Yamagata University Yonezawa Japan

The Avrami's kinetics was known to be the best theory to describe Bi-2223 crystals growth. Whereas, it cannot explain the fact that maximum product volume appearing at optimum sintering time during synthesis Bi-2223 crystal. Meanwhile, the Avrami's equation can also be used to determine the activation energy of Bi-2223 crystal growth; unfortunately, the determined activation energy, E, had dispersion as much as hard to be accepted by researchers themselves. To solve those problems, we studied and developed Avrami's kinetics and obtained a developed Avrami's kinetics equation in this research. With the developed Avrami equation, the index of growth, n, and E of Bi-2223 crystals were determined, including the periods of Bi-2223 crystals growing and decomposing. The n and E for Bi-2223 crystals were changing during synthesis period, values of which can be positive, zero or negative for different reaction periods. And the negative E and n were no reports to be found before, which caused by the decomposition of the product. The developed kinetics can describe a phase transformation system that with metastable or stable product. The developed kinetics theory, as a universal theoretical tool, is expected to be widely applied in the science and engineering multidisciplines and their related interdisciplines.

关键词： Crystals Kinetic theory Equations Mathematical model Educational institutions High temperature superconductors Australia

来源：评论

学校读者我要写书评

暂无评论

Dynamics and stability of divacancy defects in graphene

引用

Physical Review B 2011年第7期84卷 075445-075445页

作者： Youngkuk Kim Jisoon Ihm Euijoon Yoon Gun-Do Lee Department of Physics and Astronomy Seoul National University Seoul 151-747 Republic of Korea Department of Materials Science and Engineering Seoul National University Seoul 151-742 Republic of Korea Department of Nano Science and Technology Graduate School of Convergence Science and Technology Seoul National University Suwon 433-270 Republic of Korea Department of Materials Science and Engineering WCU Hybrid Materials Program Seoul National University Seoul 151-742 Republic of Korea Energy Semiconductor Research Center Advanced Institutes of Convergence Technology Seoul National University Suwon 443-270 Korea

A divacancy (DV) is one of the most abundant and most important defects in irradiated graphene, which modifies electronic and chemical properties of graphene. In this paper, we present ab initio calculations to study the dynamics and stability of DVs in graphene. Divacancies in graphene have various reconstructed structures, such as triple pentagon-triple heptagon (555-777) and pentagon-octagon-pentagon (5-8-5) patterns. A direct observation of the structural transformations between these reconstructions was recorded in transmission electron microscope images reported by Girit et al. in science 323, 1705 (2009). We clarify the atomic structures of DVs observed in the experiment and investigate the atomic processes and energetics for the observed dynamical motions in great detail. It is found that a series of Stone–Wales-type transformations are responsible for the migration and structural transformations of DVs and that a pentagon-heptagon-heptagon-pentagon (5-7-7-5) defect appearing as an intermediate structure during the dynamical process plays an important role in the transformations of DVs.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Phonon transport and thermoelectricity in defect-engineered InAs nanowires

Phonon transport and thermoelectricity in defect-engineered ...

引用

2011 MRS Fall Meeting

作者： Weathers, Annie Moore, Arden L. Pettes, Michael T. Salta, Daniel Kim, Jaehyun Dick, Kimberly Samuelson, Lars Linke, Heiner Caroff, Philippe Shi, Li Department of Mechanical Engineering University of Texas at Austin Austin TX United States Material Science and Engineering Graduate Program University of Texas at Austin Austin TX United States Center for Nano and Molecular Science University of Texas at Austin Austin TX United States Division of Solid State Physics Lund University S-22100 Lund Sweden Polymer and Materials Chemistry Lund University S-22100 Lund Sweden Institut d'Electronique de Microelectronique et de Nanotechnologie UMR CNRS 8520 F-59652 Villeneuve d'Ascq France

ISBN: (纸本)9781627482219

There have been reports of improvements in the thermoelectric figure of merit through the use of nanostructured materials to suppress the lattice thermal conductivity. Here, we report on a fundamental study of the combined effects of defect planes and surface scattering on phonon transport and thermoelectric properties of defect-engineered InAs nanowires. A microfabricated device is employed to measure the thermal conductivity and thermopower of individual suspended indium arsenide nanowires grown by metal organic vapor phase epitaxy. The four-probe measurement device consists of platinum resistance thermometers and electrodes patterned on two adjacent SiNx membranes. A nanowire was suspended between the two membranes, and electrical contact between the nanowire and the platinum electrodes was made with the evaporation of a Ni/Pd film through a shadow mask. The exposed back side of the device substrate allows for characterization of the crystal structure of the suspended nanowire with transmission electron microscopy (TEM) following measurement. The 100-200 nm diameter zincblende (ZB) InAs nanowire samples were grown with randomly spaced twin defects, stacking faults, or phases boundaries perpendicular to the nanowire growth direction, as revealed by transmission electron microscopy (TEM) analysis. Compared to single-crystal ZB InAs nanowires with a similar lateral dimension, the thermal conductivity of the defect-engineered nanowires is reduced by fifty percent at room temperature. © 2012 materials Research Society.

关键词： Nanowires

来源：评论

学校读者我要写书评

暂无评论

PDMS through-hole fabrication by soft lithography using CH4/He atmospheric RF plasma surface treatment

PDMS through-hole fabrication by soft lithography using CH4/...

引用

IEEE International Conference on Micro Electro Mechanical Systems

作者： Jongchan Choi Kyeong-Hwan Lee Ji A Choi Sun Hwa Lee Sung Yang School of Information and Mechatronics Gwangju Institute of Science and Technology Gwangju South Korea Department of Rural and Biosystems Engineering Chonnam National University Gwangju South Korea Institute of Medical System Engineering Gwangju Institute of Science and Technology Gwangju South Korea Department of Nanobio Materials and Electronics School of Information and Mechatronics Graduate Program of Medical System Engineering Gwangju Institute of Science and Technology Gwangju South Korea

This paper presents a PDMS micro through-hole molding method by simple soft lithography process in which the surface of a master mold and a substrate is treated by atmospheric CH 4 /He RF plasma to feature hydrophobic property on the surface. Rectangular and circular-shaped PDMS micro through-hole layers are made by the proposed fabrication method. As one of the applications of the PDMS micro through-hole layer for multi-layered systems, a radial concentration gradient generator including a micro through-hole layer is constructed and its performance is tested. The micro through-holes fabricated by the proposed method are well-defined. The concentration gradients measured in radial directions are in a similar level. Also, the tearing problem, which is often happened in spin-coating and lift-off molding methods, is not observed during the fabrication process of the PDMS micro through-holes. Therefore, we believe that the proposed fabrication method contributes to improve the technology for PDMS through-hole fabrication.

关键词： Surface treatment Fabrication Plasmas Substrates Helium Generators Radio frequency

来源：评论

学校读者我要写书评

暂无评论

Phonon Transport and Thermoelectricity in Defect-Engineered InAs Nanowires

引用

MRS Online Proceedings Library 2011年第1期1404卷 36-43页

作者： Weathers, Annie Moore, Arden L. Pettes, Michael T. Salta, Daniel Kim, Jaehyun Dick, Kimberly Samuelson, Lars Linke, Heiner Caroff, Philippe Shi, Li Department of Mechanical Engineering The University of Texas at Austin Austin USA Center for Nano and Molecular Science The University of Texas at Austin Austin USA Material Science and Engineering Graduate Program The University of Texas at Austin Austin USA The Nanometer Structure Consortium (nmC@LU) and Division of Solid State Physics Lund University Lund Sweden Polymer & Materials Chemistry Lund Sweden Institut d’Electronique de Microelectronique et de Nanotechnologie UMR CNRS 8520 France

关键词： thermoelectric nanostructure thermal conductivity

来源：评论

学校读者我要写书评

暂无评论

Development of continuous wrapping tantalum barriers for internal-tin Nb3Sn multi-filamentary wires

Development of continuous wrapping tantalum barriers for int...

引用

International Conference on Applied Superconductivity and Electromagnetic Devices, ASEMD

作者： Wu Ming Chen Mustafa Yavuz Xue Kui Fu Shiro Kambe Peter McIntyre Jian Xun Jin Waterloo Institute for Nanotechnology University of Waterloo Waterloo ONT Canada School of Materials Science & Engineering University of New South Wales Sydney NSW Australia Human Sensing Program Graduate School of Science and Engineering Yamagata University Yonezawa Japan Waterloo Institute for Nanotechnology University of Waterloo Cankaya University Ankara ON Turkey Department of Physics Texas A&M University TX USA Center of Applied Superconductivity and Electrical Engineering University of Electronic Science and Technology of China China

A process, continuous wrapping tantalum barrier, has been developed and investigated in order to reduce the manufacturing cost. By avoiding inserting expensive tantalum tube, a long sheet barrier was directly used to wrap a prior restack. In this work, a tantalum barrier with 20 % overlap was wrapped onto sub-elements. Then 18-filament Nb 3 Sn plus 1 copper core restack billet was successfully drawn down and extruded into round wire as thin as a diameter of 0.84 mm. The longitudinal and cross-sectional images revealed most of barriers were continuous and intact. However, further experiments are needed to optimize the process in order to keep the all barriers continuous and intact after manufacturing.

关键词： Niobium-tin Wires Copper Electron tubes Educational institutions Superconducting magnets

来源：评论

学校读者我要写书评

暂无评论

Size-dependent infiltration and optical detection of nucleic acids in nanoscale pores

Size-dependent infiltration and optical detection of nucleic...

引用

作者： Lawrie, Jenifer L. Jiao, Yang Weiss, Sharon M. Department of Electrical Engineering and Computer Science Interdisciplinary Graduate Program in Materials Science Vanderbilt University Nashville TN 37235 United States

Experiments and complimentary simulations are presented to demonstrate the size-dependent infiltration and detection of variable length nucleic acids in porous silicon with controllable pore diameters in the range of 15-60 nm. The pore diameter must be tuned according to target molecule size in order to most effectively balance sensitivity and size-exclusion. A quantitative relationship between pore size (15-60 nm), nucleic acid length (up to ~5.3 nm), and sensor response is presented with smallermolecules detected more sensitively in smaller pores as long as the pore diameter is sufficient to enable molecular infiltration and binding in the pores. The density of probe molecules on the pore walls and subsequent hybridization efficiency for targetmolecule binding are also reported and are shown to depend strongly on the method of infiltration as well as the target molecule size.© 2010 IEEE.

关键词： Porous silicon

来源：评论

学校读者我要写书评

暂无评论

Nano‐Resolution X‐ray Tomography for Deciphering Wiring Diagram of Mammalian Brain

引用

AIP Conference Proceedings 2011年第1期1365卷 399-402页

作者： H. Mizutani H. Sagara A. Takeuchi T. Ohigashi W. Yashiro K. Uesugi Y. Suzuki A. Momose T. Takagi aScience Integration Program Organization for Interdisciplinary Research Projects The University of Tokyo 5‐1‐5 Kashiwanoha Kashiwa Chiba Japan bInstitute of Medical Science the University of Tokyo 4‐6‐1 Shirokanedai Minato‐ku Tokyo Japan cJapan Synchrotron Radiation Research Institute/SPring‐8 1‐1‐1 Kouto Sayo Hyogo Japan dResearch Organization of Science & Engineering Ritsumeikan University 1‐1‐1 Noji Higashi Shiga Japan eDepartment of Advanced Materials Science Graduate School of Frontier Sciences The University of Tokyo 5‐1‐5 Kashiwanoha Kashiwa Chiba Japan

Neural circuits in the central nervous system are the substrate of various high‐order brain functions. However, little is known about the mechanisms underlying neuronal information processing in the brain. Anatomical and functional graph structures of neural networks with actual connections will provide us with perspectives to elucidate the brain complexity. Here, we aim to develop a three‐dimensional mouse brain atlas of neural circuits using nano‐resolution x‐ray tomography by synchrotron radiation. In addition to identifying a large number of synapses, our research will also clarify the structure of neuronal networks for understanding the most complex organ in the body. In this study, we observed metal‐stained biological tissues of the mouse brain using hard x‐ray Zernike‐type phase‐contrast microscopy with 60‐nm resolution at SPring‐8. As a result, the nano‐resolution hard x‐ray phase‐contrast microscope revealed nerve fibers and organelles including mitochondria and synapses in the neural tissue. In the near future, this information will be utilized to begin deciphering the wiring diagram of the brain by using nano‐resolution x‐ray tomography.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Relationship between Surface Abrasion Wear and Brightness in Glazed Porcelainized Stoneware Tiles

引用

International Scholarly Research Notices 2011年第1期2011卷

作者： Oscar Rubem Klegues Montedo Antonio Pedro Novaes de Oliveira Graduate Program in Materials Science and Engineering (PPGCEM) Universidade do Extremo Sul Catarinense (UNESC) Avendia Universitária 1105 P.O. Box 3167 88806-000 Criciúma SC *** Graduate Program in Materials Science and Engineering (PGMAT) Universidade Federal de Santa Catarina (UFSC) Campus Universitário P.O. Box 476 88040-900 Florianópolis SC Brazilufsc.br

This paper reports the results of a research work whose main objective is related to the development of a technical solution that takes into account the relationship between the surface abrasion wear resistance and brightness of glazed ceramic tile products. Thus, glazes formulated from a glass-ceramic composition belonging to the LZSA system reinforced with crystalline particles of zircon were prepared and characterized with respect to their scratching and surface abrasion wear resistances and brightness. In this context, a bright (71.2 UB) porcelainized stoneware ceramic tile with high scratching resistance (9 Mohs), high surface abrasion wear resistance (PEI 5), and good staining resistance (Class 4) was obtained.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Finite-temperature anisotropic elastic properties of Ni-Mn-In magnetic shape memory alloy

Finite-temperature anisotropic elastic properties of Ni-Mn-I...

引用

作者： Williams, Kristen S. Cagin, Tahir Materials Science and Engineering Graduate Program Texas A and M University College Station TX United States Department of Chemical Engineering Texas A and M University College Station TX United States

ISBN: (纸本)9781617822018

Designing magnetic shape memory materials with practicable engineering applications requires a thorough understanding of their electronic, magnetic, and mechanical properties. Experimental and computational studies on such materials provide differing perspectives on the same problems, with theoretical approaches offering fundamental insight into complex experimental phenomena. Many recent computational approaches have focused on first-principles calculations, all of which have been successful in reproducing ground-state structures and properties such as lattice parameters, magnetic moments, electronic density of states, and phonon dispersion curves. With all of these successes, however, such methods fail to include the effects of finite temperatures, effects which are critical in understanding how these properties couple to the experimentally-observed martensitic transformation. To this end, we apply the quasi-harmonic theory of lattice dynamics to predict the finite-temperature mechanical properties of Ni-Mn-In magnetic shape memory alloy. We employ first-principles calculations in which we include vibrational contributions to the free energy. By constructing a free energy surface in volume/temperature space, we are able to evaluate key thermodynamic properties such as entropy, enthalpy, and specific heat. We further report the elastic constants for the austenite and martensite phases and evaluate their role as a driving force for martensitic transformation. © 2010 materials Research Society.

关键词： Magnetic moments

来源：评论

学校读者我要写书评

暂无评论

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

请选择保存的检索档案：

请选择收藏分类：

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

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

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：