期刊文献+
共找到4篇文章
< 1 >
每页显示 20 50 100
在尺寸链中统计公差的目标设计 被引量:3
1
作者 李广利 《低压电器》 2013年第12期12-14,共3页
叙述了机械结构设计中尺寸链统计公差的目标设计,以及各种影响目标设计的因素,为尺寸公差分析的设计和产品质量的控制提供了依据。
关键词 统计公差 一维线性尺寸 平面尺寸 目标设计
下载PDF
有限长度碳纳米管的一维链模型
2
作者 杨莉 《清华大学学报(自然科学版)》 EI CAS CSCD 北大核心 2007年第3期412-415,共4页
碳纳米管独特的电子性质使其在纳米电子器件中有很好的应用前景,而其电子性质强烈依赖于其手征性和长度,这使得研究它的有限尺寸效应有重要意义。该文采用一维线性链模型模拟有限长度扶手椅型碳纳米管的轴向边界条件,通过求解紧束缚近... 碳纳米管独特的电子性质使其在纳米电子器件中有很好的应用前景,而其电子性质强烈依赖于其手征性和长度,这使得研究它的有限尺寸效应有重要意义。该文采用一维线性链模型模拟有限长度扶手椅型碳纳米管的轴向边界条件,通过求解紧束缚近似下的一维线性链的本征值和本征矢,得到了碳纳米管能隙随着长度的振荡特性,并且给出了它最低未占据分子轨道和最高占据分子轨道的波函数模的平方。此方法计算得到的波函数模的平方与利用四轨道紧束缚方法计算碳纳米管体系所得的结果,在形状以及量值方面吻合得很好。证明了一维线性链模型可以描述纳米管的轴向边界条件进而给出纳米管的电子结构性质。 展开更多
关键词 碳纳米管 一维线性链 能隙 波函数模的平方
原文传递
Synthesis and Crystal Structure of a Novel Polymer Copper(Ⅱ) Complex
3
作者 王军 卑凤利 +3 位作者 李人宇 杨绪杰 陆路德 汪信 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2003年第6期665-668,共4页
A novel chain complex was synthesized and its crystal structure has been deter- mined by X-ray diffraction technique. It was found that the local coordination geometry around Cu(Ⅱ) is a distorted tetrahedron and C14H... A novel chain complex was synthesized and its crystal structure has been deter- mined by X-ray diffraction technique. It was found that the local coordination geometry around Cu(Ⅱ) is a distorted tetrahedron and C14H9CuNO3CH3OH is bridged by the carboxylate oxygen atom to form an infinite one-dimensional linear chain. The hydrogen bond exists between O(1) and solvate molecule O(4). The crystal belongs to monoclinic, space group P21 with a = 9.6650(19), b = 7.1280(14), c = 9.925(2) ? b = 98.39(3)? V = 676.4(2) 3, Z = 2, F(000) = 342 and m(MoK? = 1.629 mm-1 . 展开更多
关键词 SALICYLALDEHYDE o-aminobenzoic acid crystal structure one-dimensional chain N-salicylidene-2-amino-phenylacidato copper(Ⅱ)
下载PDF
Computer Simulation Study of Thermal Conduction in 1D Chains of Anharmonic Oscillators
4
作者 Tejal N.Shah P.N.Gajjar 《Communications in Theoretical Physics》 SCIE CAS CSCD 2013年第3期361-364,共4页
In this work thermal conduction in one-dimensional (1D) chains of anharmonic oscillators are studied using computer simulation. The temperature profile, heat flux and thermal conductivity are investigated for chain ... In this work thermal conduction in one-dimensional (1D) chains of anharmonic oscillators are studied using computer simulation. The temperature profile, heat flux and thermal conductivity are investigated for chain length N = 100, 200, 400, 800 and 1600. In the computer simulation anharmonicity is introduced due to Fermi-Pasta- U1am-β (FPU-β) model For substrate interaction, an onsite potential due to Frenkel-Kontorova (FK) model has been used. Numerical simulations demonstrate that temperature gradient scales behave as N-1 linearly with the relation J = 0.1765/N. For the thermal conductivity K, KN to N obey the linear relation of the type KN = 0.8805N. It is shown that thermal transport is dependent on phonon-phonon interaction as web as phonon-lattice interaction. The thermal conductivity increases linearly with increase inanharmonicity and predicts relation κ =0.133 + 0.804β. It is also concluded that for higher value of the strength of the onsite potential system tends to a thermal insulator. 展开更多
关键词 heat conduction thermal conductivity Anharmonic oscillator Fermi-Pasta-Ulam model Frenkel-Kontorova model
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部