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First-principles calculations of elasticity and thermodynamic properties of LaNi5 crystal under pressure 下载免费PDF全文
This paper investigates the equilibrium lattice parameters, heat capacity, thermal expansion coefficient, bulk modulus and its pressure derivative of LaNi 5 crystal by using the first-principles plane-wave pseudopotential method in the GGA-PBE generalized gradient approximation as well as the quasi-harmonic Debye model. The dependences of bulk modulus on temperature and on pressure are investigated. For the first time it analyses the relationships between bulk modulus B and temperature T up to 1000 K, the relationship between bulk modulus B and pressure at different temperatures are worked out. The pressure dependences of heat capacity C v and thermal expansion α at various temperatures are also analysed. Finally, the Debye temperatures of LaNi 5 at different pressures are successfully obtained. The calculated results are in excellent agreement with the experimental data. 相似文献
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阐释了软交换技术的概念,分析了基于软交换的开放网络体系结构和软交换的基本功能,指出了多媒体软交换在下一代网络的演进发展中的积极推动作用,对我国多媒体软交换技术的发展策略提出了几点建议。 相似文献
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基于C/S与B/S模式的实验室管理系统设计与实现 总被引:4,自引:0,他引:4
结合实践教学和实验室管理的特点,基于C/S和B/S混合结构,采用ADO、ASP、SQL Server2000等技术平台,利用校园网络环境开发了实验室信息管理系统,促进了实验室实行规范化管理、信息数据集中处理与共享、资源合理调配与有效利用.本文介绍了系统设计理念、功能结构及其实现的主要技术手段. 相似文献
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合成和表征了新的三元配合物:[Cu(L-His)(5′-AMP)]Cl_2·4H_2O,[Cu(L-His)(5′-GMP)]Cl_2,[Cu(L-His)(5′-IMP)]Cl_2·2H_2O,[Cu(L-Lys)_2(5′-GMP)]Cl_2·6H_2O,Na_2[Cu(L-Lys)_2(5′-GMPH_(-2)]·6H_2O,Na_2[Cu(L-Lys)_2(5′GTP_(-2))]·6H_2O,Na_2[Cu(L-Lsy)_2(5′-IMPH_(-2))]·10H_2O.IR及NMR谱表明,5′-嘌呤核苷酸以嘌呤碱基上的7-N原子与Cu(Ⅱ)配位.在5′-嘌呤核苷酸形成的配合物中,磷酸根不参与配位,但是Na_2·5′-GMPH_(-2)和Na_2·5′-GTPH_(-2)的磷酸根参与配位,而Na_2·5′-IMPH_(-2)的磷酸根不参与配位. 相似文献