首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   37篇
  免费   3篇
  国内免费   3篇
化学   13篇
晶体学   1篇
力学   3篇
综合类   2篇
数学   7篇
物理学   17篇
  2023年   2篇
  2022年   3篇
  2021年   2篇
  2020年   2篇
  2019年   1篇
  2018年   1篇
  2016年   1篇
  2015年   2篇
  2014年   1篇
  2013年   2篇
  2012年   1篇
  2010年   1篇
  2009年   2篇
  2008年   2篇
  2006年   3篇
  2004年   1篇
  2003年   1篇
  2001年   2篇
  2000年   2篇
  1998年   1篇
  1997年   4篇
  1996年   3篇
  1995年   1篇
  1994年   2篇
排序方式: 共有43条查询结果,搜索用时 15 毫秒
1.
富镧和富铈混合稀土贮氢电极的性能   总被引:1,自引:0,他引:1  
富镧和富铈混合稀土贮氢电极的性能*赵东江马松艳(黑龙江省绥化师专化学系绥化市152061)关键词混合稀土贮氢电极性能中图分类号O646.54混合稀土贮氢合金具有良好的电化学特性和较低的价格,成为贮氢电极研究的主要对象,已经开发出许多实用的电极材料[1...  相似文献   
2.
Journal of Computer-Aided Molecular Design - When employing molecular dynamics (MD) simulations for computer-aided drug design, the quality of the used force fields is highly important. Here we...  相似文献   
3.
我们在低压金属有机汽相沉积(MOCVD)设备上采用两步升温法与金属有机源流量周期调制生长界面过渡层方法制备出GaAs-InP材料,并对此进行了X-射线衍射、低温光致发光谱(PL)和Raman谱分析,结果表明,GaAs外延层的位错密度低于用两步升温法得到的GaAs材料,PL谱峰较强,GaAs的特征激子峰和杂质相关的激子峰同时被测到。Raman谱PL谱的峰移表明GaAs外延层处于(100)双轴伸张应力下,应力大小随温度变化是由于GaAs、InP之间的热膨胀系数不同。  相似文献   
4.
研究了弱紧凸集值上鞅及无界集值上鞅的Riesz逼近,以及鞅型集序列的若干收敛定理.  相似文献   
5.
In this article, we give the three-sphere inequalities and three-ball inequalities for the singular elliptic equation div(A▽u)-V u = 0, and the three-ball inequalities on the characteristic plane and the three-cylinder inequalities for the singular parabolic equation ■tu-div(A▽u)+ V u = 0, where the singular potential V belonging to the Kato-Fefferman- Phong’s class. Some applications are also discussed.  相似文献   
6.
Dynamic responses of a carriage under excitation with the German high-speed low-interference track spectrum together with the air pressure pulse generated as high-speed trains passing each other are investigated with a multi-body dynamics method.The variations of degrees of freedom(DOFs:horizontal movement,roll angle,and yaw angle),the lateral wheel-rail force,the derailment coefficient and the rate of wheel load reduction with time when two carriages meet in open air are obtained and compared with the results of a single train travelling at specifie speeds.Results show that the rate of wheel load reduction increases with the increase of train speed and meets some safety standard at a certain speed,but exceeding the value of the rate of wheel load reduction does not necessarily mean derailment.The evaluation standard of the rate of wheel load reduction is somewhat conservative and may be loosened.The pressure pulse has significan effects on the train DOFs,and the evaluations of these safety indexes are strongly suggested in practice.The pressure pulse has a limited effect on the derailment coefficien and the lateral wheel-rail force,and,thus,their further evaluations may be not necessary.  相似文献   
7.
ABSTRACT

Inverted perovskite solar cells (PSCs) have attracted much attention due to their low-temperature and solution-based process. Electron transport layers are important components in inverted PSCs. Non-fullerene n-type organic small molecules seem to be more attractive as electron transport layers, because their structures are easy to be synthesised and modified. In this paper, density functional theory and semi-classical Marcus electron transfer theory were used to explore the electron transport properties in three azaacene derivatives, including one experimentally reported molecule, 1,4,9,16-tetrakis((triisopropylsilyl)ethynyl)quinoxalino[2?,3?:4,5]cyclopenta[1,2,3:5,6]acenaphtho[1,2:5,6]pyrazino[2,3-b]phenazine (1), and two theoretically designed molecules (2 and 3). Compound 2 is formed by substituting i-Pr groups in compound 1 with H atoms, which is designed to evaluate the effect of i-Pr groups on the electron transport properties. Compound 3 is designed by adding one more benzopyrazine group to the conjugation structure of compound 1. It shows that i-Pr group can increase HOMO and LUMO energy levels and improve solubility in organic solvent and hydrophobicity. Enlarging conjugation can not only decrease LUMO energy level and electron reorganisation energy, but also can increase solubility and electron mobility. So our designed compound 3 is expected to be a potential electron transport material in inverted PSCs.  相似文献   
8.
MlNi4Al和MlNi4Mn贮氢电极性能的研究*赵东江马松艳(绥化师专化学系绥化152061)关键词贮氢电极循环寿命自放电中图分类号O646.54镍/氢化物(Ni/MH)二次电池以其洁净、安全、高容量、大功率及长寿命等特点受到极大关注。贮氢电极材料...  相似文献   
9.
本文首次报导了生长温度为550℃,以三甲基镓(TMGa)和三甲基铟(TMIn)为Ⅲ族源,用低压金属有机物气相沉积(LFMOCVD〕技术,高质量1.62um和1.3umInGaAsP及In0.57Ga0.43As0.98P0.04/In0.73Ga0.27As0.6P0.4量子阶结构的生长,并给出了1.55umGaAsP/InP分别限制应变量子阱结构激光器的生长条件,激光器于室温下脉冲激射,其阈值电流密度为2.4kA/cm2。  相似文献   
10.
非光滑区域上Schrodinger方程的L~2-Neumann问题   总被引:1,自引:0,他引:1  
考虑在无界Lipschitz区域上Schrodinger方程-u、i(dll0的L2-Neumann边值问题。假设位势非负且满足逆Holder条件,本文证明上面问题的解存在唯一,并且具有一致正则性。  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号