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51.
用电化学方法研究了I-3和Ti3+在还原铂表面上的电极反应,由此计算出I-3与Ti3+在还原铂表面上的混合催化反应速率(νmix).当混合催化电位(Emix)位于极限电流区时,νmix对[Ti3+]为零级反应,对[I-3]为一级反应,且正比于电极旋转速率的平方根,H+浓度影响不大.由动力学方法研究的结果证实了电化学研究结果的正确性,致使可用电化学方法解释溶液中的异相催化问题 相似文献
52.
Sizov A. I. Zvukova T. M. Belsky V. K. Bulychev B. M. 《Russian Chemical Bulletin》2001,50(11):2200-2202
The heterometallic zirconocene(iii) aluminum hydride complex (Cp2ZrH)2HAlCl2·C4H8O2·C6H6 was synthesized by reduction of Cp2ZrCl2 with lithium aluminum hydride in the presence of Cp2TiBH4 and 1,4-dioxane, and its structure was established by X-ray diffraction analysis. 相似文献
53.
A short and facile synthesis of a series of 1,2-dihydroquiazolin-4(3H)-ones was accomplished in good yields via novel reductive cyclization of o-nitrobenzamides with ketones promoted by TiCI4/Zn system. The structure was established on the basis of elemental analysis, IR,^1H NMR and confirmed by a single-crystal X-ray diffraction analysis. This method has the advantages of easily accessible starting materials, convenient manipulation and moderate to high yields. 相似文献
54.
Dispersion state and catalytic properties of vanadia species on the surface of V_2O_5/TiO_2 catalysts 总被引:1,自引:0,他引:1
The dispersion state and catalytic properties of anatase-supported vanadia species are studied by means of X-ray diffraction (XRD), laser Raman spectroscopy (LRS), H2 temperature-programmed reduction (TPR) and the selective oxidation of o-xylene to phthalic anhydride. The almost identical values of the experimental dispersion capacity of V2O5 on anatase and the surface vacant sites available on the preferentially exposed (001) plane of anatase suggest that the highly dispersed vanadium cations are bonded to the vacant sites on the surface of anatase as derived by the incorporation model. When the loading amount of V2O5 is far below its dispersion capacity, the dispersed vanadia species might mainly consist of isolated VOx species bridging to the surface through V-O-Ti bonds. With the increase of V2O5 loading the isolated vanadia species interact with their nearest neighbors (either isolated or polymerized vanadia) through bridging V-O-V at the expenses of V-O-Ti bonds, resulting in the increase of the ra 相似文献
55.
56.
本工作采用电化学工作站研究了电子束熔化技术(EBM)成形TC4样品和传统锻造TC4在3.5wt% NaCl溶液中的电化学腐蚀行为. 结果表明EBM成形TC4样品的非平衡微观结构使其与传统锻造的TC4相比,表现出不同的耐腐蚀性. EBM成形TC4样品与锻件TC4相比,EBM成形样品不同平面存在耐蚀性差异,而且EBM水平面大于锻件,EBM垂直面小于锻件. EBM成形TC4样品垂直面出现的腐蚀性能的各向异性主要是β柱状晶导致的. 在腐蚀的过程中,点蚀优先发生在α晶界,因为晶界能量较高,形成多孔的钝化层. 本项工作有助于丰富增材制造制备TC4合金在航空钛合金领域的腐蚀性能研究. 相似文献
57.
TiO2制备条件对光催化氧化活性的影响 总被引:14,自引:2,他引:12
半导体光催化剂,如TiO2,在紫外光照射下,生成具有强氧化还原活性的电子和空穴,可使许多有机物降解为CO2和H2O,用于处理工业废水具有成本低,无二次污染等优点,是一种很有应用前景的废水催理方法[1,2].制备高活性的TiO2光催化剂是这种过程在处理... 相似文献
58.
Complexes of azobisisobutyronitrile (AIBN) with titanium tetrachloride and vanadium tetrachloride have been synthesized and characterized. It was demonstrated that Ti(IV) and V(IV) form equimolar complexes with AIBN, with nitrile ligands located incis positions in the coordination spheres of metal atoms. Kinetics of thermal decomposition of free and complexed AIBN were studied and compared. The gas evolution rate was measured in the presence of tetrabutoxytitanium, which does not react with AIBN. It was demonstrated that complexing leads to a marked increase of the rate constant of AIBN thermal decomposition.Institute of Chemical Physics, Chernogolovka, Russian Academy of Sciences, 142432 Chernogolovka. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 8, pp. 1746–1754, August, 1992. 相似文献
59.
Yu. E. Roginskaya F. Kh. Chibirova T. L. Kulova A. M. Skundin 《Russian Journal of Electrochemistry》2006,42(4):355-362
Products of lithium interaction with thin-film nanostructured SnO2-TiO2 (ST) oxides are studied with the aid of x-ray diffraction analysis and Moessbauer spectroscopy on the 119Sn nuclei. Electrochemical properties of a series of the ST electrodes with different concentrations of TiO2 varied from 0 to 20 mol % are also examined. It is concluded that the specific feature of the charge-discharge mechanism of the ST electrodes is a significant participation of oxygen in reversible reactions during insertion and extraction of lithium as compared with an alloying mechanism of operation of tin-containing anodes. The leading role in this is played by titanium oxide. Remaining stable towards reduction by lithium, it facilitates the holding of the neighboring layers of SnO2 in a nanodisperse state and in an oxidized state. The effect of a decrease in the capacity degradation in modified TiO2 electrodes, which is discovered in this work, is attributed to the hampering of the growth of nanocrystallites of β-Sn by interlayers of tin and titanium oxides mentioned above. 相似文献
60.