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271.
Here we investigate whether the deformation observed in an experiment in which the porcine circumflex coronary artery is subjected
to inflation at constant length included in the class,
,
,
. We find that this is not the case and discuss its implications in the study of the mechanics of this artery. Moreover, we
identify and quantify the uncertainty in the value of the invariants of the left Cauchy–Green tensor inferred from the 2D
motion of markers affixed to the surface of the test specimen, and suggest that 3D tracking of markers is needed due to inherent
bending and twisting induced by pressurization in vitro. 相似文献
272.
V. Arjunan I. Saravanan P. Ravindran S. Mohan 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2009,74(2):375-384
The Fourier transform infrared (FTIR) and FT-Raman spectra of 4-amino-2-methylquinoline (AMQ) have been recorded in the range 4000–400 and 4000–100 cm−1, respectively. The experimental vibrational frequency was compared with the wavenumbers obtained theoretically by ab initio HF and DFT–B3LYP gradient calculations employing the standard 6-31G** and high level 6-311++G** basis sets for optimised geometry of the compound. The complete vibrational assignment and analysis of the fundamental modes of the compounds were carried out using the experimental FTIR and FT-Raman data, and quantum mechanical studies. The geometry and normal modes of vibration obtained from the HF and DFT methods are in good agreement with the experimental data. The potential energy distribution of the fundamental modes was calculated with ab initio force fields utilising Wilson's FG matrix method. The NH-π interactions and the influence of amino and methyl groups on the skeletal modes are investigated. 相似文献
273.
Saravanan Peruncheralathan Dr. Henrik Teller Christoph Schneider Prof. Dr. 《Angewandte Chemie (International ed. in English)》2009,48(26):4849-4852
It's as simple as that : An in situ prepared chiral catalyst from the commercially available compounds Ti(OiPr)4 and (R)‐binol catalyzes the highly enantioselective ring‐opening of meso‐aziridines 1 with anilines 2 and furnishes valuable chiral 1,2‐diamines 3 in high yields and up to 99 % ee.(R)‐binol=(R)‐2,2′‐dihydroxy‐1,1′‐binaphthyl.
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Using a total of 1052 Bragg reflections of silicon, an X-ray investigation has been carried out to deduce the anharmonic thermal parameter β, apart from the estimation of the harmonic contribution of the thermal vibration at room temperature. Reflections of type h + k + l = 4n, and 4n ± 1 were used to estimate these parameters using MoK α radiation and a Nonius CAD-4 X-ray diffractometer. We obtain Bsi, = 0.451(0.008) Å2 and βsi = 0.279(2.630) eV Å−3 with R = 3.12%. The present B and β values are in very good agreement with the earlier studies. 相似文献
278.
Sruthi Thiraviam Saravanan Saritha Poopandi Yen-Chieh Huang Amala Mathimaran Jeyakanthan Jeyaraman Chun-Jung Chen 《中国化学会会志》2023,70(5):1228-1236
Lymphatic filariasis (LF) is a debilitating mosquito-borne parasitic disease caused by Brugia malayi in humans in the lymphatic system. Although limited drugs are available to treat this disease, these drugs are only effective against the larvae of Brugia malayi. As resistance has been reported to the available drugs, a new antifilarial drug is needed with better prognostic features, a short period of time of use, and efficiency at preventing adult worm survival. In this study, we have targeted succinyl-diaminopimelate desuccinylase (DapE) from the Wolbachia endosymbiont of Brugia malayi (WBm), which is involved in the production of lysine and meso-diaminopimelic acid, an essential component for the formation of bacterial cell walls, and plays a vital role in pathogen survival. Deletion of DapE gene is lethal to WBm since the organism has no alternative pathway for lysine biosynthesis. Here, the expression, purification, and crystallization of DapE are reported. The crystals of DapE, with an estimated solvent content of 50.76%, diffract synchrotron X-rays to a resolution of 2.3 Å and belong to the space group C2221, with unit-cell parameters of a = 51.78, b = 78.83, and c = 216.20 Å. The X-ray absorption spectroscopy further confirms that zinc atoms are incorporated in DapE. 相似文献
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