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101.
一种铈(Ⅲ)配合物对含石墨粘结涂层耐蚀性的影响 总被引:1,自引:0,他引:1
为了改善含石墨粘结涂层的耐蚀性,首先对这种涂层在腐蚀环境中耐蚀性差的原因进行了分析,然后将二正丁基磷酸、CeF_3、Sb_2O_3和一种Ce(Ⅲ)配合物Ce(NO_3)(C_8H_(18)PO_4)_2分别添加于酚醛环氧-MoS_2-石墨粘结涂层中,考察了它们对这种涂层耐蚀性的影响,并对含Ce(NO_3)(C_8H_(18)PO_4)_2的涂层和空白样涂层进行了表面分析。盐雾试验表明,添加Ce(NO_3)(C_8H_(18)PO_4)_2可以有效地抑制涂层中MoS_2的氧化和由石墨所引起的金属底材之电化学腐蚀;根据X射线光电子能谱分析结果可知,添加Ce(NO_3)(C_8H_(18)PO_4)_2之所以能够提高含石墨粘结涂层的耐蚀性,应当归因于它在MoS_2晶体表面和金属底材表面的吸附。因此,Ce(Ⅲ)配合物Ce(NO_3)(C_8H_(18)PO_4)_2是含石墨粘结涂层的一种实用性能良好的新型防腐添加剂。 相似文献
102.
6,7-Dialkynyl-1,3-dimethylpteridine-2,4(1H,3H)-diones and 2,3-dialkynylquinoxalines have been shown to react with sodium azide in DMF at room temperature giving rise 9,11-dimethyl-[1,2,3]triazolo[1′,5′;1,2]pyrido[4,3-g]pteridine-8,10(9H,11H)-diones and [1,2,3]triazolo[1′,5′;1,2]pyrido[3,4-b]quinoxalines. A novel tandem cyclization involves 1,3-dipolar cycloaddition of an azide ion to the carbon-carbon triple bond followed by intramolecular nucleophilic addition of the intermediate 1,2,3-triazole N-anion to another CC bond. 相似文献
103.
T. A. Dang H.‐J. Lunk S. Roychowdhury T. A. Frisk T. J. Bard 《Surface and interface analysis : SIA》2010,42(1):45-51
Solid standards prepared by freeze‐drying consistently showed a high degree of homogeneity. The freezing process, completed in fractions of a second, preserves the original homogeneous distribution of the dopants, and the subsequent sublimation step would minimize any disturbance. Compared to those prepared by conventional methods such as blending and spiking, freeze‐dried standards exhibited superior lateral distribution and better uniform depth distribution. There is, however, a concentration constraint for achieving homogeneity. At 5% doping, segregation was observed in both lateral and depth distribution. Many tungsten standards doped with 10–28 elements ranging from 10 to 200 ppm were successfully prepared and used as controls for a number of analytical techniques including glow discharge mass spectrometry (GDMS) and d.c.‐arc optical emission spectroscopy (OES). Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
104.
105.
Plate impact experiments on the (210), (100), and (111) planes were performed to examine the role of crystalline anisotropy on the shock-induced decomposition of cyclotrimethylenetrinitramine (RDX) crystals. Time-resolved emission spectroscopy was used to probe the decomposition of single crystals shocked to peak stresses ranging between 7 and 20 GPa. Emission produced by decomposition intermediates was analyzed in terms of induction time to emission, emission intensity, and the emission spectra shapes as a function of stress and time. Utilizing these features, we found that the shock-induced decomposition of RDX crystals exhibits considerable anisotropy. Crystals shocked on the (210) and (100) planes were more sensitive to decomposition than crystals shocked on the (111) plane. The possible sources of the observed anisotropy are discussed with regard to the inelastic deformation mechanisms of shocked RDX. Our results suggest that, despite the anisotropy observed for shock initiation, decomposition pathways for all three orientations are similar. 相似文献
106.
Abstract
A new Cu(II) coordination polymer [Cu(3,5-pdc)(H2O)4·H2O] n 1 (3,5-pdc=3,5-pyridinedicarboxylic acid) has been synthesized by hydrothermal method and characterized by IR, elemental analysis, TG technique and X-ray crystallography. The crystallographic data for the compound 1: monoclinic P21/n, a = 11.361(5) ?, b = 7.095(3) ?, c = 14.575(6) ?, β = 107.630(4)°, V = 1,119.7(8) ?3, Z = 4, Dc = 1.891 Mg/m3, F(000) = 652, R 1 = 0.0374, wR 2 = 0.1083. Cu(II) atom has an distorted octahedral environment with N2O4 donor set of Cu(1) and O6 donor set of Cu(2), respectively. Each ligand is bound to two Cu(II) ions and each copper atom is coordinated by two ligands thereby generating a 1D zigzag chain. The 1D chain was interacted each other feathering three-dimensional supramolecular network through π···π interactions and multiform intermolecular hydrogen bonds. The luminescent properties of the title complex in the solid state were investigated. 相似文献107.
Song Dang Jiangbo Yu Lining Sun Jing Feng Hongjie Zhang 《Journal of luminescence》2011,131(9):1857-1863
The ligand 1-(2-naphthyl)-4,4,4-trifluoro-1,3-butanedionate (Htfnd) has been employed to synthesize six novel ternary-lanthanide complexes in which the synergic ligands were 1,10-phenanthroline-5,6-dione (dione) and 4,5-diazafluoren-9-one (dafone), respectively. Two series of complexes Ln(tfnd)3dione and Ln(tfnd)3dafone (Ln=Ho, Pr, Tm) were obtained. These complexes were characterized by elemental analysis, Fourier Transform Infrared spectra and diffused reflectance. After ligand-mediated excitation, Ln(tfnd)3dione and Ln(tfnd)3dafone all show the characteristic NIR luminescence of the corresponding Ln3+ ions (Ln=Ho, Pr, Tm). This can be attributed to the efficient energy transfer from ligands to central Ln3+ ions, via an antenna effect. The indirect energy transfer in the complexes has been investigated and the differences in the luminescence intensity between Ln(tfnd)3dione and Ln(tfnd)3dafone were discussed in detail. The excellent luminescent performances enable these NIR-luminescent complexes to have potential applications in optical amplification operating at 1300 or 1500 nm. 相似文献
108.
水氯镁石脱水是镁资源利用的关键.其中一种重要的方法是向水氯镁石中添加助剂形成复盐及络合物脱水.通过缓慢冷却水氯镁石及盐酸苯胺的过饱和水溶液制备了水氯镁石-盐酸苯胺结晶物.通过TGDTA-FTIR联用技术分析了盐酸苯胺、水氯镁石以及盐酸苯胺-水氯镁石结晶物的热解过程,定性检测每步分解的逸出气体以推测反应过程.结果显示:盐酸苯胺在400℃以前仅发生物理变化;水氯镁石的热解分阶段进行,205℃以前发生脱去四个结晶水,205℃以后在脱水反应的同时发生水解反应生成HCl;盐酸苯胺-水氯镁石结晶物分阶段脱水、脱盐酸苯胺,整个过程没有水解现象发生,能够得到高纯度无水氯化镁. 相似文献
109.
110.