全文获取类型
收费全文 | 840篇 |
免费 | 41篇 |
国内免费 | 5篇 |
专业分类
化学 | 559篇 |
晶体学 | 13篇 |
力学 | 37篇 |
数学 | 123篇 |
物理学 | 154篇 |
出版年
2024年 | 9篇 |
2023年 | 14篇 |
2022年 | 13篇 |
2021年 | 44篇 |
2020年 | 26篇 |
2019年 | 32篇 |
2018年 | 36篇 |
2017年 | 25篇 |
2016年 | 55篇 |
2015年 | 25篇 |
2014年 | 23篇 |
2013年 | 42篇 |
2012年 | 50篇 |
2011年 | 61篇 |
2010年 | 48篇 |
2009年 | 48篇 |
2008年 | 40篇 |
2007年 | 33篇 |
2006年 | 31篇 |
2005年 | 24篇 |
2004年 | 25篇 |
2003年 | 10篇 |
2002年 | 15篇 |
2001年 | 6篇 |
2000年 | 6篇 |
1999年 | 5篇 |
1998年 | 4篇 |
1997年 | 6篇 |
1996年 | 8篇 |
1995年 | 7篇 |
1994年 | 3篇 |
1993年 | 13篇 |
1992年 | 6篇 |
1991年 | 7篇 |
1990年 | 4篇 |
1988年 | 5篇 |
1987年 | 3篇 |
1986年 | 7篇 |
1985年 | 7篇 |
1984年 | 8篇 |
1983年 | 5篇 |
1982年 | 5篇 |
1981年 | 4篇 |
1980年 | 7篇 |
1979年 | 5篇 |
1978年 | 4篇 |
1974年 | 2篇 |
1973年 | 3篇 |
1965年 | 3篇 |
1959年 | 2篇 |
排序方式: 共有886条查询结果,搜索用时 93 毫秒
91.
In this Note we present a justification of the kinematic assumptions for thin-walled rods with shallow profile. These assumptions are fundamental to writing the one-dimensional equilibrium equations for such structures. The obtained kinematics are different from the Vlassov case, which is only valid for strongly curved profiles. They are also different from the that classically used in shell theory. The justification given in this Note is based on an asymptotic approach. To cite this article: L. Grillet et al., C. R. Mecanique 333 (2005). 相似文献
92.
Simultaneous flow of two or three immiscible fluids in porous media is modelled by a system of coupled, nonlinear partial differential equations. These equations are reduced to a system of nonlinear algebraic equations through the use of finite-difference approximations for derivatives. Several types of nonlinearities requiring careful analysis exist in this model. Here, we present a systematic study of all available, and some new, methods for the treatment of nonlinearitics in this model. It is believed that the solution techniques presented here may also prove useful for other strongly nonlinear partial differential equations. 相似文献
93.
94.
In order to preserve the physical properties of the flow (scaling laws, conservation laws, …) during the simulation, a class of subgrid models respecting the symmetry group of the Navier–Stokes equations is built. The class is then refined such that models satisfy the second law of thermodynamics and are suited to take into account the inverse energy cascade. A simple model belonging to the class is tested and a better result than those provided by Smagorinsky and dynamic models is obtained. To cite this article: D. Razafindralandy, A. Hamdouni, C. R. Mecanique 333 (2005). 相似文献
95.
Dr. Hamed Shaykhalishahi Dr. Aziz Gauhar Michael M. Wördehoff Dr. Clara S. R. Grüning Antonia N. Klein Dr. Oliver Bannach Dr. Matthias Stoldt Prof. Dr. Dieter Willbold Prof. Dr. Torleif Härd Dr. Wolfgang Hoyer 《Angewandte Chemie (International ed. in English)》2015,54(30):8837-8840
Conversion of the intrinsically disordered protein α‐synuclein (α‐syn) into amyloid aggregates is a key process in Parkinson’s disease. The sequence region 35–59 contains β‐strand segments β1 and β2 of α‐syn amyloid fibril models and most disease‐related mutations. β1 and β2 frequently engage in transient interactions in monomeric α‐syn. The consequences of β1–β2 contacts are evaluated by disulfide engineering, biophysical techniques, and cell viability assays. The double‐cysteine mutant α‐synCC, with a disulfide linking β1 and β2, is aggregation‐incompetent and inhibits aggregation and toxicity of wild‐type α‐syn. We show that α‐syn delays the aggregation of amyloid‐β peptide and islet amyloid polypeptide involved in Alzheimer’s disease and type 2 diabetes, an effect enhanced in the α‐synCC mutant. Tertiary interactions in the β1–β2 region of α‐syn interfere with the nucleation of amyloid formation, suggesting promotion of such interactions as a potential therapeutic approach. 相似文献
96.
97.
Muhammad Asif Ayesha Aziz Anh Quang Dao Abdul Hakeem Haitao Wang Shuang Dong Guoan Zhang Fei Xiao Hongfang Liu 《Analytica chimica acta》2015
We report a facile and green method for the fabrication of new type of electrocatalysts based on MnO2 nanoparticles incorporated on MgAl LDH P-type semiconductive channel and explore its practical applications as high-performance electrode materials for electrochemical biosensor. A series of MgAl layered doubled hydroxide (LDH) nanohybrids with fixed Mg/Al (M2+/M3+ atomic ratio of 3) and varied amount of MnCl2.4H2O are fabricated by a facile co-precipitation method. This approach demonstrates the combination of distinct properties including excellent intercalation features of LDH for entrapping nanoparticles and high loading of MnO2 nanoparticles in the host layers of LDH. Among all samples, Mn5–MgAl with 0.04% loaded manganese has a good crystalline morphology. A well-dispersed MnO2 nanoparticles encapsulated into the host matrix of hydrotalcite exhibit enhanced electrocatalytic activity towards the reduction of H2O2 as well as excellent stability, selectivity and reproducibility due to synergistic effect of good catalytic ability of MnO2 and conductive MgAl LDH. Glass carbon electrode (GCE) modified with Mn5–MgAl possesses a wide linear range of 0.05–78 mM, lowest detection limit 5 μM (S/N = 3) and detection sensitivity of 0.9352 μAmM−1. This outstanding performance enables it to be used for real-time tracking of H2O2 secreted by live HeLa cells. This work may provide new insight in clinical diagnosis, on-site environmental analysis and point of care testing devices. 相似文献
98.
In this paper we give several characterizations of almost limited operators. Mainly, it is proved that an operator \(T:X\rightarrow E\) from a Banach space X into a \(\sigma \)-Dedekind complete Banach lattice E is almost limited if and only if \(\left\| T^{*}\left( f_{n}\right) \right\| \rightarrow 0\) for every positive weak\(^{*}\) null sequence \(\left( f_{n}\right) \) of \(E^{*}\). Moreover, we present some interesting connections between almost limited, almost Dunford–Pettis and limited operators. 相似文献
99.
Aziz N. Abdel 《Fluid Dynamics》1993,28(5):736-738
The phenomenon of thermal relaxation of the gas bubbles in a fluid behind a shock front is analyzed. The approach to solving the problem of heat transfer between a gas bubble and a fluid developed by the author is used to obtain a solution describing the initial stage of bubble collapse behind the shock front.Translated from Izvestiya Rossiiskoi Akademii Nauk, Mekhanika Zhidkosti i Gaza, No. 5, pp. 187–189, September–October, 1993. 相似文献
100.
In this work, we study the existence, uniqueness, and exponential asymptotic behavior of mild solutions to stochastic integrodifferential delay evolution equations. We assume that the non-delay part generates a C0-semigroup. 相似文献