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161.
Rolf Appel Nikolaos Siabalis 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3-4):273-274
Abstract Reactions of carbonyl cyclopentadienyl hydrides from molybdenum and tungsten with 1,4-diphosphabuta-1,3-diene yield metalla-diphospha-pentadiene with a metal-phosphorus-double bond. Metalla-diphosphapentadiene mit einer Metall-Phosphor-Doppelbindung werden durch Umsetzung von Carbonylcyclopentadienylhydriden des Molybdäns und Wolframs mit einem 1,4-Diphospha-buta-1,3-dien erhalten. 相似文献
162.
L. Hargitai 《International journal of environmental analytical chemistry》2013,93(2-4):317-325
Abstract Investigations of the distribution and mobility of Pb, Ni, Cd and Hg have shown that Pb is strongly associated with humic substances in the top layer of soils and in river sediments, and that Pb shows the highest organophilicity. Ni is very organophilic, and Cd, somewhat less so. The hydrophilicity of Hg highly influences its movement in soil profiles and river sediments. The risk of contamination by these metals is characterized through the environment protection capacity (EPCG) values which combine humus content and the quality and thickness of the humus layer in one parameter. The risk of contamination is highest at low EPCG values. Increase of EPCG decreases the risk of environmental contamination through binding of heavy metals to humic substances, decreasing their mobility. 相似文献
163.
Electron-phonon coupling in cuprate and iron-based superconductors revealed by Raman scattering 下载免费PDF全文
Electron-phonon coupling (EPC) in cuprate and iron-based superconducting systems, as revealed by Raman scat- tering, is briefly reviewed. We introduce how to extract the coupling information through phonon lineshape. Then we discuss the strength of EPC in different high-temperature superconductor (HTSC) systems and possible factors affecting the strength. A comparative study between Raman phonon theories and experiments allows us to gain insight into some crucial electronic properties, especially superconductivity. Finally, we summarize and compare EPC in the two existing HTSC systems, and discuss what role it may play in the HTSC. 相似文献
164.
《Physics and Chemistry of Liquids》2012,50(4):255-265
Abstract The experimental procedure of determining the structure of a liquid by diffraction techniques is reformulated herein as a stochastic experiment subject to the data analysis formalism of statistical spectral analysis. Observed in such an experiment are averaged local microscopic fluctuations from the bulk density. The intensity function then represents a stochastic spectrum and it becomes necessary to statistically estimate a minimum bias, minimum variance covariance function which is the net radial distribution function. A low-pass tapered data window produces such an optimum estimate. 相似文献
165.
《合成通讯》2012,42(1):85-96
AbstractTwelve bis-thiadiazole derivatives were synthesized in high yield via the reaction of 2,2′-terephthaloyl bis(N-phenylhydrazine carbothioamide) with a variety of hydrazonoyl chlorides in ethanol containing catalytic amounts of TEA. All the newly synthesized compounds were characterized by physical and chemical tools (FT-IR, 1H NMR, 13C NMR, and Mass spectrometry). Moreover, all the novel synthesized derivatives were screened for their antihypertensive α-blocking efficacy against to assess their pharmaceutical significance. The encouraging promising results obtained from antihypertensive α-blocking activity studies on the newly synthesized derivatives make the synthesis of a new series of these compounds and studying of their pharmaceutical importance an active area for more and more investigations. The molecular docking of the most active derivative 15?b against the human dopamine D3 receptor was performed by the Molecular Operating Environment (MOE 2014. 0901) program. 相似文献
166.
《Analytical letters》2012,45(12):1285-1291
Abstract The polynuclear aromatic compounds (PNA): anthracene, napthalene, phenanthrene, pyrene, pyrenecarboxaldehyde, benzo (a) pyrene, benzo (e) pyrene, perylene and fluorene can be chromatographed on polyamide TLC sheets using an aqueous micellar solution cf sodium dodecylsulfate (SDS) as the mobile phase. Reversed micellar solutions (of sodium dioctylsulfosuccinate) were used in a reverse phase chromatographic separation of amino acids. Some amino acids tended to streak slightly rather than move as discrete spots. Conditions could be adjusted, however, so that most of the amino acids and all PNA's would move as spots. 相似文献
167.
Norio Kondo 《国际流体数值方法杂志》2012,70(2):158-185
We present numerical results for in‐line and cross‐flow vibrations of a circular cylinder, which is immersed in a uniform flow and is elastically supported by damper‐spring systems to compute vibrations of a rigid cylinder. In the case of a circular cylinder with a low Scruton number, it is well‐known that two types of self‐excited vibrations appear in the in‐line direction in the range of low reduced velocities. On the other hand, a cross‐flow vibration of the circular cylinder can be excited in the range of high reduced velocities. Therefore, we compute the flow‐induced vibrations of the circular cylinder in the wide range of the reduced velocities at low and high Scruton numbers and discuss about excitation mechanisms in the in‐line and cross‐flow directions. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
168.
We report the results of our investigation of magnetization and heat capacity on a series of compounds CeYxNiGe2 () under the influence of external magnetic field. Our studies of the thermodynamic quantity on these compounds indicate that magnetic frustration persists in Ce0.9Y0.1NiGe2, as also reported for the parent compound CeNiGe2. The weak signature of this frustration is also noted in Ce0.8Y0.2NiGe2, whereas, it is suppressed in Ce0.6Y0.4NiGe2. Heat capacity studies on Ce0.9Y0.1NiGe2 and Ce0.8Y0.2NiGe2 indicate the presence of a new magnetic anomaly at high field which indicates that quantum criticality is absent in these compounds. However, for Ce0.6Y0.4NiGe2 such an anomaly is not noted. For this later compound, the magnetic field (H) and temperature (T) dependence of heat capacity and magnetization obey scaling above critical fields. However, the obtained scaling critical parameter (δ) is 1.6, which is away from mean field value of 3. This deviation suggests the presence of unusual fluctuations and anomalous quantum criticality in these compounds. This unusual fluctuation may arise from disorderness induced by Y-substitution. 相似文献
169.
170.