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41.
The overlap factors for bond electrons in various diatomic halides are calculated making use of a simple relation where the overlap factor is an inverse exponential function of the difference between the two atomic radii of the molecule concerned. These overlap factors together with the hybridization values of 15 percent for Cl, and 10 percent for Br and I are used to calculate the ionic characters for various diatomic molecules from the values of the nuclear quadrupole coupling constants obtained by earlier workers. These ionic characters are then plotted against electronegativity differences and the points are found to be fairly well represented by a smooth curve. It is shown that this curve can in general be used for the determination of the ionic characters in the halogen containing single bonds of certain polyatomic molecules. The quadrupole coupling constants are calculated from the ionic characters obtained from the curve and are compared with those observed. The effects of the distortion of the closed shells and of the neighbouring ions oneQq are discussed. 相似文献
42.
S. K. Banerjee B. V. R. Chowdari Putcha Venkateswarlu 《Proceedings Mathematical Sciences》1970,71(2):49-55
Electron paramagnetic resonance spectrum of the Cu2+ ion in CsCl is studied at different temperatures. The local symmetry at the Cu2+ site is found to be tetragonal. A model of substitutional Cu2+ ion associated with a first neighbour cation vacancy is proposed to explain the observed spectrum. 相似文献
43.
The electron spin resonance spectra of Mn2+ in NaCl single crystals are investigated in detail. Seven different spectra (I, II, III1, III2, IV, V and VI) are observed. The spectra I–IV are the same as those observed by earlier workers, while the spectra V and VI are observed here for the first time. The local symmetry at the paramagnetic ion is orthorhombic for the spectra IV and V and tetragonal for the spectrum VI about the crystallographic [001] direction. The properties of the spectrum IV are explained in terms of an associated pair Mn2+: O2 2? with O2 2? molecular ion at the nearest neighbour anion site in the [001] direction with its internuclear axis in the (001) plane. The spectrum V is assigned to the associated pair Mn2+: O2 2? coupled with a nearby cation vacancy in the [001] direction and the spectrum VI to Mn2+ ion associated with OH? ion at the anion site in the [001] direction with a probable second neighbour cation vacancy. All the observed spectra are analysed in terms of the parameters of the usual spin-Hamiltonian. 相似文献
44.
The anharmonicity factors of B2H6 and B2D6 have been calculated using Dennison’s method. Using the calculated harmonic wave numbers, the valence force constants have been obtained by the Wilson’s F-G matrix method. 相似文献
45.
From spectrochemical studies on the blue complex resulting from uranyl and alizarin-S, it has been shown that a compound in the stoichiometric ratio 1:1 of uranyl and reagent is formed. The compound is stable at pH 8.2. The peaks of absorption of the reagent at 520 mu; and of the uranyl compound at 570 mμ have been accounted for, applying kuhn's relationship. 相似文献
46.
A theoretical treatment of the generalised mean-square amplitudes of vibration of some silicon compounds of XY3Z type molecules is presented. The numerical values evaluated for the parallel and perpendicular mean-square amplitudes for all the bonded and non-bonded atom pairs are tabulated. The L matrix elements and Coriolis coefficients have also been evaluated for these molecules. 相似文献
47.
48.
The intensities of Raman lines due to CH, CH2 and CH3 groups in the case of some n-paraffin hydrocarbons have been obtained relative to the peak intensity of the 458 cm?1 line of CCl4 and compared. The integrated intensity as well as the standard intensity of the C=O frequency in some unconjugated and conjugated ketones, aldehydes and esters have been obtained and the influence of conjugation has been discussed. The intensity of the C=C frequency has also been obtained in the conjugated compounds and compared with the results obtained for the unconjugated compounds. 相似文献
49.
B. D. Nageswara Rao Putcha Venkateswarlu F.A.Sc. 《Proceedings Mathematical Sciences》1961,54(6):305-320
The ring proton resonance spectra ofα, β andγ picolines have been studied at 40 Mc./sec. The spectra which belong to the classes ABCX, ABXY and A2X2 respectively have been completely analyzed to determine all the involved parameters. 相似文献
50.
Normal coordinate analysis for XY4 type molecules of T
symmetry has been carried out by the Wilson F — G matrix method. Following Dennison and making use of the spectral data the anharmonicity factors for B'H
4
–
, B'D
4
–
, B10H
4
–
and B10D
4
–
have been calculated and potential constants have been evaluated for borohydride isotopic ions. 相似文献