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1.
Maximiliano A. Burgos Paci Gustavo A. Argüello Plcido García Helge Willner 《国际化学动力学杂志》2003,35(1):15-19
Thermal decomposition of bis(trifluoromethyl) peroxydicarbonate has been studied. The mechanism of decomposition is a simple bond fission, homogeneous first‐order process when the reaction is carried out in the presence of inert gases such as N2 or CO. An activation energy of 28.5 kcal mol?1 was determined for the temperature range of 50–90°C. Decomposition is accelerated by nitric oxide because of a chemical attack on the peroxide forming substances different from those formed with N2 or CO. An interpretation on the influence of the substituents in different peroxides on the O? O bond is given. © 2002 Wiley Periodicals, Inc. Int J Chem Kinet 35: 15–19, 2003 相似文献
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The Fourier transform infrared spectrum of monoisotopic SC80Se has been investigated in the ν2, ν3, 2ν2, 2ν3, and ν1 regions with a resolution between 3 and 4 × 10−3 cm−1. In addition, the millimeter-wave spectrum has been studied in the region 150 to 320 GHz, and ground and ν2 = 1 excited state transitions have been measured. Ground state constants, B0 = 2043.285 4(4) MHz and D0 = 146.53(5) Hz, have been determined from a merge of millimeter-wave data and ground state combination differences spanning J values up to 77 and 143, respectively. The band centers ν2 = 352.341 075(9) cm−1 and ν3 = 505.480 06(5)cm−1 have been determined. The rovibrational parameters of numerous overtone and combination levels (ν1νl22ν3) = 0200, 0220, 0310, 0330, 0400, 0420, 0002, and 0003 have been obtained from polynomial analyses whose standard deviations ranged from 0.7 to 3.5 × 10−4 cm−1. The 1000 level, νeff 1435.840 cm−1, is anharmonically perturbed by the 0400 level, with an avoided crossing at J = 55, and W12222 = 0.963 09(1) cm−1. Transitions to both the upper (E+) and lower (E−) sublevels of the dyad were observed for 1 ≤ J′ ≤ 117 and 4 ≤ J′ ≤ 171, respectively, and the deperturbed wavenumbers ν1 = 1435.542 76(2) and 4ν02 = 1432.725 00(3) cm−1 were derived. Furthermore, a local crossing of the E− and 0420 levels involving l-type resonance was observed at J = 91. 相似文献
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Marc Halpern Yoel Sasson Itamar Willner Mordecai Rabinovitz 《Tetrahedron letters》1981,22(18):1719-1722
The effects of water molecules and quat structure are shown to be significant in determining the behavior of alkylation reactions of weakly acidic carbon acids under PTC/OH? conditions. 相似文献
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Torsten Küppers Martin Köckerling Prof. Dr. Helge Willner Prof. Dr. 《无机化学与普通化学杂志》2007,633(2):280-284
The new tetracyanoborate K[B(CN)4]·CH3CN was synthesized by dissolution of the solvent‐free K[B(CN)4] in acetonitrile and subsequent careful crystallization. The crystal structure has been determined by single‐crystal X‐ray diffraction. It crystallizes in the orthorhombic space group P212121 with Z = 4. Some comparisons with related structures are made, and the vibrational spectrum is discussed. 相似文献
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Bröchler R Sham IH Bodenbinder M Schmitz V Rettig SJ Trotter J Willner H Aubke F 《Inorganic chemistry》2000,39(10):2172-2177
The reaction of tungsten hexacarbonyl, W(CO)6, with antimony(V) fluoride, SbF5, in the conjugate Br?nsted-Lewis superacid HF-SbF5 at 40 degrees C produces quantitatively the salt [W(CO)6(FSbF5)][Sb2F11] as the main product. The observed 2e- oxidation without any loss of CO is unprecedented. The cation [W(CO)6(FSbF5)]+ is seven coordinated with a distorted C2v capped trigonal prismatic structure. [W(CO)6(FSbF5)][Sb2F11] crystallizes in the monoclinic space group P21 (No. 4). a = 8.2051(12) A, b = 16.511(3) A, c = 8.1432(2) A, beta = 111.5967(6) degrees, V = 1025.8(2) A3, Z = 2. Number of reflections measured = 9112, unique 4410. Residuals on F, I > 3 sigma (I): R (Rw) = 0.023 (0.023). In the [W(CO)6(FSbF5)]+ cation the FSbF5 group is very tightly coordinated to tungsten with the bridging fluorine nearly equidistant from W and Sb. The details of the molecular structure are compared to those to polymeric [[Mo(CO)4]2(cis-mu-F2SbF4)3]x[Sb2F11]x reported by us very recently. 相似文献
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Lower Chalcogen Fluorides. IV. Preparation and Characterization of Pure S2F4 Reactions of S and COS, respectively, with elemental fluorine in a metal high vacuum apparatus give a mixture of SF6, SF4, S?SF2, and S2F4. At ? 78°C S2F4 can be freed from impurities and isolated in a pure state. Molecular weight, density, melting point, vapour pressure, boiling point, IR, UV-, 19F-NMR, and mass spectra are presented. 相似文献