全文获取类型
收费全文 | 182篇 |
免费 | 4篇 |
国内免费 | 2篇 |
专业分类
化学 | 97篇 |
晶体学 | 1篇 |
力学 | 10篇 |
数学 | 48篇 |
物理学 | 32篇 |
出版年
2024年 | 2篇 |
2023年 | 3篇 |
2022年 | 2篇 |
2021年 | 10篇 |
2020年 | 6篇 |
2019年 | 5篇 |
2018年 | 8篇 |
2017年 | 9篇 |
2016年 | 11篇 |
2015年 | 3篇 |
2014年 | 4篇 |
2013年 | 12篇 |
2012年 | 6篇 |
2011年 | 15篇 |
2010年 | 10篇 |
2009年 | 10篇 |
2008年 | 7篇 |
2007年 | 6篇 |
2006年 | 10篇 |
2005年 | 8篇 |
2004年 | 8篇 |
2003年 | 3篇 |
2002年 | 9篇 |
2001年 | 4篇 |
2000年 | 5篇 |
1999年 | 2篇 |
1997年 | 2篇 |
1996年 | 2篇 |
1995年 | 1篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1992年 | 1篇 |
1986年 | 1篇 |
1983年 | 1篇 |
排序方式: 共有188条查询结果,搜索用时 328 毫秒
181.
In this paper, we characterize the stabilization of some delay systems. The proof of the main result uses the method introduced
in Ammari and Tucsnak (ESAIM COCV 6:361–386, 2001) where the exponential stability for the closed loop problem is reduced
to an observability estimate for the corresponding uncontrolled system combined with a boundedness property of the transfer
function of the associated open loop system.
The author would like to thank the Institute of Research for Development of France (IRD) and LMDP, the Laboratory of Mathematics
and Dynamic of Populations in Marrakesh, for supporting his visit. 相似文献
182.
This work presents a numerical study of a latent heat storage unit (LHSU) consisting of a shell-and-tube. The shell space is filled with two phase change materials (PCMs), P116 and n-octadecane, with different melting temperatures (50 °C and 27.7 °C, respectively). A heat transfer fluid (HTF: water) flows by forced convection through the inner tube, and transfers the heat to PCMs. In order to compare the thermal performances of the latent heat storage unit using two phase change materials (LHSU2) and a single PCM (LHSU1), a mathematical model based on the conservation energy equations was developed and validated with experimental data. Several numerical investigations were conducted in order to examine the impact of the key parameters: the HTF inlet temperature (ranges from 50 to 60 °C), the mass flow rate of the HTF and the proportion mass of PCMs, on the thermal performances of the latent heat storage units using two PCMs and a single PCM, during charging process (melting). This parametric study provides guidelines for system thermal performance and design optimization. 相似文献
183.
The dc conductance, the universal quantum fluctuations and the resistance distribution are numerically investigated in dimer semiconductor superlattices by means of the transfer matrix formalism. We are interested in the GaAs/Alx Ga 1 − xAs layers, having identical thickness, where the aluminium concentration x takes, at random, two different values, with the constraint that one of them appears only in pairs, i.e. the random dimer barrier (RDB). These systems exhibit a miniband of extended states, around a critical energy, lying to the typical structure of the dimer cell. The states close to this resonant energy consist of weakly localized states, while in band tails i.e. for negligible conductance, the states are strongly localized. This is evidence of the suppression of localization in the RDB superlattices. The nature of the transition between these two regimes is quantitatively investigated through relevant physical quantities. The model is, hence, clearly and statistically examined. 相似文献
184.
185.
Rajia Ait Benhamou Gilles Wallez Pascal Loiseau Bruno Viana Mohamed Elaatmani Mohamed Daoud Abdelwahed Zegzouti 《ChemInform》2010,41(52):no-no
RbMgPO4 is synthesized by solid state reaction of stoichiometric mixtures of Rb2CO3, 4MgCO3·Mg(OH)2·5H2O, and (NH4)2HPO4 (900 °C, 12 h). 相似文献
186.
187.
Poly[ethylene‐co‐(1‐octene)] nanocomposites with different microstructures were prepared with two kinds of organoclay by melt intercalation. X‐ray diffraction and transmission electron microscopy were used to characterize the morphology of the composites. Linear storage moduli of the composites in the melt state were found to increase greatly with increasing the extent of dispersion of silicate layers and showed an obvious sensitivity to the morphologies of the composites. 相似文献
188.
Ait-karra A. Zakir O. Ait baha A. Lasri M. Idouhli R. Elyaagoubi M. Abouelfida A. Khadiri M. Benzakour J. 《Journal of Solid State Electrochemistry》2023,27(8):2051-2065
Journal of Solid State Electrochemistry - Copper sulfide (CuS) thin film was electrodeposited onto stainless steel (SS 316L) substrate under pulse potential control, from an aqueous acidic solution... 相似文献