排序方式: 共有27条查询结果,搜索用时 0 毫秒
21.
《光谱实验室》2012,(1):79
《北京天科邮票展览馆》由《科学家纪念邮票展览馆》、《陆达纪念馆》和《卢嘉锡纪念馆》等3部分组成,是本刊兴办的公益性企业,免费参观。在北京市工商行政管理局注册号为:110229009367903;北京市质量技术监督局颁发的组织机构代码为:78616185X;北京市国家税务局和北京市地方税务局颁发的税务登记证号为:11022978616185X;中国人民银行颁发的开户许可证核准号为:J1000047864702;开户行为:北京市农商银行夏都支行,账号:1403000103000010416。国有土地使用证的证号为:京延国用(2002出)字第283号;房屋所有权 相似文献
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23.
非港湾式公交车站停靠特性的研究 总被引:1,自引:1,他引:0
基于Nagel-Schreckenberg交通流模型(简称NaSch模型),通过引入换道规则,建立包含非港湾式公交车站在内的双车道混合车辆元胞自动机交通流模型.计算机数值模拟表明,在周期边界条件下非港湾式公交车站路段的交通流存在一定的特性,在中等密度区域的拥挤流, 车辆的平均速度与车流密度存在一次幂律关系. 相似文献
24.
This letter is concerned with the plane and axisymmetric stagnation-point flows and heat transfer of an electrically-conducting
fluid past a stretching sheet in the presence of the thermal radiation and heat generation or absorption. The analytical solutions
for the velocity distribution and dimensionless temperature profiles are obtained for the various values of the ratio of free
stream velocity and stretching velocity, heat source parameter, Prandtl number, thermal radiation parameter, the suction and
injection velocity parameter and magnetic parameter and dimensionality index in the series form with the help of homotopy
analysis method (HAM). Convergence of the series is explicitly discussed. In addition, shear stress and heat flux at the surface
are calculated. 相似文献
25.
<正>In this work,the formation sites,helical parameters and hydrogen bond positions of Konjac glucomannan molecular helices were investigated using molecular dynamic simulation method.To our interest,the KGM chain is mainly composed by local left and right helix structures. The formation sites of KGM chain might locate at the chain-segments containing acetyl groups,and the left helix is the favorable conformation of KGM.Temperature-dependent molecule conformation study indicates that the right helix is dominant when the temperature is lower than 343 K,above which,however,the left helix is dominating(right helix disappears).In addition,intramolecular hydrogen bonds in the left helix can be found at the-OH groups on C(2),C(4)and C(6)of mannose residues;comparably,the intramolecular hydrogen bonds in the right helix can be mainly observed at the-OH groups on C(4)and C(6)of the mannose residues and C(3)of the glucose residues.In conclusion,molecular dynamic simulation is an efficient method for the microscopic conformation study of glucomannan molecular helices. 相似文献
26.
Fayyaz Hussain Sardar Sikandar Hayat Zulfiqar Ali Shah Najmul Hassan Shaikh Aftab Ahmad 《中国物理 B》2013,(9):496-504
The molecular dynamics simulation technique with many-body and semi-empirical potentials (based on the embedded atom method potentials) has been used to calculate the interactions of point defects with (1 1 1), (1 1 3), and (1 2 0) twin boundaries in Au at different temperatures. The interactions of single-, di-, and tri-vacancies (at on- and off-mirror sites) with the twin interfaces at 300 K are calculated. All vacancy clusters are favorable at the on-mirror arrangement near the (1 1 3) twin boundary. Single- and di-vacancies are more favorable at the on-mirror sites near the (1 1 l) twin boundary, while they are favorable at the oft-mirror sites near the (1 2 0) twin boundary. Almost all vacancy clusters energetically prefer to lie in planes closest to the interface rather than away from it, except for tri-vacancies near the (1 2 0) interface at the off-mirror site and for 3.3 and 3.4 vacancy clusters at both sites near the (1 1 1) interface, which are favorable away from the interface. The interaction energy is high at high temperatures. 相似文献
27.
研究一种基于计算机视觉原理获取飞行目标姿态方法在实施过程中地面测量站点的布设问题,提出目标贴近地面和在高空飞行两种情况下测量站点的布设方案,指出测量站点布设时需要考虑目标像长、两交会平面之间夹角等影响因素,并要避免发生奇异情况. 相似文献