全文获取类型
收费全文 | 48篇 |
免费 | 3篇 |
国内免费 | 1篇 |
专业分类
化学 | 25篇 |
晶体学 | 1篇 |
力学 | 2篇 |
数学 | 5篇 |
物理学 | 19篇 |
出版年
2022年 | 1篇 |
2020年 | 1篇 |
2018年 | 1篇 |
2016年 | 1篇 |
2013年 | 2篇 |
2012年 | 5篇 |
2011年 | 5篇 |
2010年 | 1篇 |
2008年 | 2篇 |
2007年 | 3篇 |
2006年 | 2篇 |
2005年 | 2篇 |
2004年 | 1篇 |
2003年 | 2篇 |
2002年 | 7篇 |
2001年 | 2篇 |
1999年 | 2篇 |
1998年 | 1篇 |
1996年 | 2篇 |
1994年 | 2篇 |
1993年 | 1篇 |
1992年 | 1篇 |
1989年 | 2篇 |
1987年 | 1篇 |
1980年 | 1篇 |
1957年 | 1篇 |
排序方式: 共有52条查询结果,搜索用时 15 毫秒
1.
Multi-domained heteroepitaxial rutile-phase TiO2 (1 0 0)-oriented films were grown on Si (1 0 0) substrates by using a 30-nm-thick BaF2 (1 1 1) buffer layer at the TiO2–Si interface. The 50 nm TiO2 films were grown by electron cyclotron resonance oxygen plasma-assisted electron beam evaporation of a titanium source, and the growth temperature was varied from 300 to 600 °C. At an optimal temperature of 500 °C, X-ray diffraction measurements show that rutile phase TiO2 films are produced. Pole figure analysis indicates that the TiO2 layer follows the symmetry of the BaF2 surface mesh, and consists of six (1 0 0)-oriented domains separated by 30° in-plane rotations about the TiO2 [1 0 0] axis. The in-plane alignment between the TiO2 and BaF2 films is oriented as [0 0 1] TiO2 || BaF2 or [0 0 1] TiO2 || BaF2 . Rocking curve and STM analyses suggest that the TiO2 films are more finely grained than the BaF2 film. STM imaging also reveals that the TiO2 surface has morphological features consistent with the BaF2 surface mesh symmetry. One of the optimally grown TiO2 (1 0 0) films was used to template a CrO2 (1 0 0) film which was grown via chemical vapor deposition. Point contact Andreev reflection measurements indicate that the CrO2 film was approximately 70% spin polarized. 相似文献
2.
Selecting optimal location is a key decision problem in business and engineering. This research focuses to develop mathematical models for a special type of location problems called grid-based location problems. It uses a real-world problem of placing lights in a park to minimize the amount of darkness and excess supply. The non-linear nature of the supply function (arising from the light physics) and heterogeneous demand distribution make this decision problem truly intractable to solve. We develop ILP models that are designed to provide the optimal solution for the light post problem: the total number of light posts, the location of each light post, and their capacities (i.e., brightness). Finally, the ILP models are implemented within a standard modeling language and solved with the CPLEX solver. Results show that the ILP models are quite efficient in solving moderately sized problems with a very small optimality gap. 相似文献
3.
We discuss the notion of spin squeezing considering two mutually exclusive classes of spin-s states, namely, oriented and non-oriented states. Our analysis shows that the oriented states are not squeezed while non-oriented
states exhibit squeezing. We also present a new scheme for construction of spin-s states using 2s spinors oriented along different axes. Taking the case of s=1, we show that the ‘non-oriented’ nature and hence squeezing arise from the intrinsic quantum correlations that exist among
the spinors in the coupled state. 相似文献
4.
AA Yan LI Kai CAO ZhongHua & HU WenRui Key Laboratory of Microgravity 《中国科学:物理学 力学 天文学(英文版)》2011,(2)
The dependency of the critical Marangoni number on the geometrical aspect ratio of the floating half zone is essential to predict the onset of oscillatory thermocapillary convection.The experimental studies in the microgravity conditions on floating half zones of several centimeters in diameter have predicted that the critical Marangoni number increases with the increasing aspect ratio,and the terrestrial experimental studies have predicted the contradictory conclusion for floating half zones of several mil... 相似文献
5.
Non-Gravitational Effects with Density-Matching in Evaluating the Influence of Sedimentation on Colloidal Coagulation 下载免费PDF全文
The method of density matching between the solid and liquid phases is often adopted to effectively eliminate the effect of sedimentation of suspensions in studies on dynamic behaviour of a colloidal system. However, the associated changes in the solvent composition may bring side effects to the properties investigated and therefore might lead to a faulty conclusion if the relevant correction is not made. To illustrate the importance of this side effect, we present an example of the sedimentation influence on the coagulation rate of suspensions of 2μm (diameter) polystyrene. The liquid mixtures, in the proper proportions of water (H2O), deuterium oxide (D2O) and methanol (MeOH) as the liquid phase, density-matched and unmatched experiments are performed. Besides the influence of viscosity, the presence of methanol in solvent media, used to enhance the sedimentation effect, causes significant changes (reduction) in rapid coagulation rates compared to that in pure water. Without the relevant corrections for those non-gravitational factors it seems that gravitational sedimentation would retard the coagulation. The magnitude of the contribution from the non-gravitational factor is quantitatively determined, making the relevant correction possible. After necessary the influence of the sedimentation on coagulation rates at corrections for all factors, our experiments show that the initial stage of the coagulation is not observable. 相似文献
6.
7.
8.
9.
10.
Tran AB Melly GC Doucette R Ashcraft B Sebren LJ Havko N Young JC O'Neil GW 《Organic & biomolecular chemistry》2011,9(22):7671-7674
A convergent and scalable synthesis of the archazolid western hemisphere has been completed. The V-ATPase inhibitory activity of this compound along with a previously prepared eastern domain was then tested using a convenient Arabidopsis-based V-ATPase assay. 相似文献