全文获取类型
收费全文 | 320篇 |
免费 | 5篇 |
国内免费 | 1篇 |
专业分类
化学 | 177篇 |
晶体学 | 15篇 |
力学 | 9篇 |
综合类 | 1篇 |
数学 | 29篇 |
物理学 | 95篇 |
出版年
2022年 | 3篇 |
2021年 | 2篇 |
2019年 | 8篇 |
2018年 | 7篇 |
2017年 | 4篇 |
2016年 | 18篇 |
2015年 | 8篇 |
2014年 | 8篇 |
2013年 | 22篇 |
2012年 | 18篇 |
2011年 | 13篇 |
2010年 | 10篇 |
2009年 | 7篇 |
2008年 | 7篇 |
2007年 | 7篇 |
2006年 | 14篇 |
2005年 | 15篇 |
2004年 | 14篇 |
2003年 | 9篇 |
2002年 | 4篇 |
2001年 | 3篇 |
1997年 | 2篇 |
1996年 | 6篇 |
1995年 | 7篇 |
1994年 | 10篇 |
1993年 | 8篇 |
1992年 | 4篇 |
1991年 | 3篇 |
1990年 | 5篇 |
1989年 | 4篇 |
1988年 | 4篇 |
1987年 | 3篇 |
1986年 | 9篇 |
1985年 | 6篇 |
1984年 | 8篇 |
1983年 | 8篇 |
1982年 | 6篇 |
1981年 | 3篇 |
1980年 | 3篇 |
1979年 | 5篇 |
1978年 | 5篇 |
1977年 | 3篇 |
1976年 | 3篇 |
1975年 | 1篇 |
1974年 | 1篇 |
1973年 | 1篇 |
1971年 | 1篇 |
1970年 | 1篇 |
1969年 | 1篇 |
1966年 | 1篇 |
排序方式: 共有326条查询结果,搜索用时 15 毫秒
321.
Manju Sharma Rohit Soni Asiya Nazir Harinder Singh Oberoi Bhupinder Singh Chadha 《Applied biochemistry and biotechnology》2011,163(5):577-591
A thermotolerant Aspergillus fumigatus strain isolated from composting pile of mixed industrial waste was found to produce a spectrum of cellulase and hemicellulases
when cultured on rice straw solidified substrate. The two-dimensional electrophoresis (2DE) resolved the secretome into 57
distinct protein spots. The zymograms developed against 2DE gels identified the presence of three β-glucosidases and five
CBHI/EGI isoforms in the secretome. The peptide mass fingerprinting of 17 protein spots by liquid chromatography mass spectrometry
characterized the secretome into different glycosyl hydrolase families. The enzyme cocktail produced by A. fumigatus was capable of efficient hydrolysis of alkali pretreated rice straw (at 7% and 10% w/v) resulting in 95% and 91% saccharification, respectively. 相似文献
322.
We carried out the heat capacity calculation of the magnetoresistance compounds EuMnO3 and Eu0.7A0.3MnO3 (where A=Ca and Sr) as a function of temperature from 5 to 100 K, using the Rigid Ion Model (RIM). The results on heat capacity for EuMnO3 and Eu0.7A0.3MnO3 (A=Ca and Sr) obtained by us are in good agreement with the measured values. Although strong electron–phonon interactions are present in these compounds but the lattice part of the specific heat also deserves proper attention. The parent compound EuMnO3 exhibits two magnetic transitions at 35 and 47 K due to weak ferromagnetic (FM) component and antiferromagnetic (AF) ordering. In addition, we have reported cohesive energy (φ), molecular force constant (f), compressibility (β), Restrahalen frequency (υ0), Debye temperature (θD) and Gruneisen parameter (γ) in the temperature range 5 K?T?100 K. 相似文献
323.
We report on the specific heat C(T) of doped manganites Nd0.5Sr0.5MnO3, Nd0.5Ca0.5MnO3, Sm0.5Ca0.5MnO3, Dy0.5Ca0.5MnO3 and Ho0.5Ca0.5MnO3 in the temperature range 2?T?300 K using modified rigid ion model (MRIM). The present specific heat results are in general satisfactory agreement with experimental data except at very low temperatures (i.e. T?12 K). Also a sharp peak observed in the experimental results for these compounds around 5 K could not be revealed by our computed results as they arise due to Schottky-like anomaly. Besides, we have reported the cohesive and the thermal properties of these compounds. The results obtained by us are discussed in detail. 相似文献
324.
Santosh Kumar Kudtarkar Renu Dhadwal 《Journal of magnetism and magnetic materials》2010,322(16):2287-2292
We determine the induced voltage generated by spatial and temporal magnetisation textures (inhomogeneities) in metallic ferromagnets due to the spin diffusion of non-equilibrium electrons. Using time dependent semi-classical theory as formulated in Zhang and Li [1] and the drift-diffusion model of transport it is shown that the voltage generated depends critically on the difference in the diffusion constants of up and down spins. Including spin relaxation results in a crucial contribution to the induced voltage. We also show that the presence of magnetisation textures results in the modification of the conductivity of the system. As an illustration, we calculate the voltage generated due to a time dependent field driven helimagnet by solving the Landau-Lifshitz equation with Gilbert damping and explicitly calculate the dependence on the relaxation and damping parameters. 相似文献
325.
Sanket?Chougale Dhammaraj?Rokade Tanushree?Bhattacharjee Harshawardhan?PolEmail author Renu?DhadwalEmail author 《Rheologica Acta》2018,57(6-7):493-503
Extrusion film casting (EFC) is an industrially important process which produces thousands of tons of polymer films, sheets, and coating used for various industrial as well as household applications. In this paper, we focus on an instability which occurs during certain polymer processing operations operating under predominantly elongational flow, such as extrusion film casting and fiber spinning. This instability, called the draw resonance, occurs in the form of sustained periodic fluctuations in the film dimensions. It appears when the process goes beyond the critical line speed of the EFC process. In this work, a conventional linear stability analysis is carried out for nonisothermal EFC process to determine the onset of the draw resonance. The polymer rheology is modeled by the Phan-Thien Tanner (PTT) multi-mode constitutive equation. For the implementation, a conventional shooting method approach is used. Extrusion film casting experiments were also carried out using a conventional linear low-density polyethylene (LLDPE) by varying process parameters such as draw ratio and aspect ratio, to observe the effect on the stability of the process. Linear stability analysis results under non-isothermal conditions are compared and validated with existing results from literature and with our own experimental data. This work displays the effect of multiple relaxation modes as well as the temperature influence on the stability of EFC process. Finally, results also indicate that the temperature highly affects the stability of the EFC process and cannot be ignored from modeling of EFC process. 相似文献
326.
CdI2 has been purified using the zone-refining technique by giving 20 passes. Single crystals grown from the starting material showed arcing in the X-ray oscillation photographs whereas it is absent in the crystals grown from the zone refined material. These crystals are found to be of the 4 H type. DC conductivity studies were made on these crystals at various stages of purification. The surface morphology of these crystals have been studied using an optical microscope. 相似文献