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61.
By use of a fused-silica hook for holding the sample packet in a Schöniger combustion flask, even difficultly combustible phosphorus compounds can be completely decomposed. 相似文献
62.
It is demonstrated that for Ne-like systems, the zeroth-plus-first-order wavefunctions, obtained within Rayleigh—Schrödinger perturbation theory based on H0 = HHF, are of the same accuracy as variational wavefunctions obtained in CI calculations using very extensive sets of singly and doubly excited configurations. Variational correlation energies for Na+, Mg2+ and Ar8+ are reported for the first time. 相似文献
63.
Leszek Szaro 《Surface science》1984,137(1):311-326
The simple theory of the surface photovoltage induced by photostimulated electron transitions from the bulk impurity levels is given. The relevant calculations show that the surface barrier height, the concentration of the impurity levels and the trapping process at the surface effectively control this phenomenon. Under the proper conditions, a very low excitation level in the bulk can generate significant surface photovoltage signals. 相似文献
64.
A simple method for determining the surface slope of a specimen under test in the high-sensitivity grating interferometry setup is proposed. The information on the derivative of out-of-plane displacement is obtained by software subtraction of two primary interferograms: a conventional one and one with diffraction orders laterally displaced in the image plane. Very good coincidence between the theoretical and experimental results has been obtained. The method can be used for studying static and transient events depending on the fringe pattern analysis method used. 相似文献
65.
Leszek Natkaniec Mikołaj F. Rudolf Bogusława Jeźowska-Trzebiatowska 《Theoretical chemistry accounts》1973,28(2):193-199
Results of SCCC MO calculations for the dimeric oxygen double-bridged [Mo2O4Cl4(H2O)2]2–ion are reported. On the basis of these results the previously reported spectra and magnetic properties may be explained. The strong direct molybdenum — molybdenum interaction in the Mo2O
4
2+
core was proved to exist.
Zusammenfassung Die Ergebnisse von SCCC MO-Rechnungen für das zweikernige Ion [Mo2O4Cl4(H2O)2]2– mit zweifacher Sauerstoffbrücke werden mitgeteilt. Danach können die früher angeführten magnetischen und spektralen Eigenschaften dieses Ions verstanden werden. Die Existenz starker unmittelbarer Molybdän-Molybdän Wechselwirkungen innerhalb des Mo2O 4 2+ Kerns wird nachgewiesen.
Résumé Résultats de calculs SCCCMO pour l'ion dimère Mo2O4Cl4(H2O) 2 2– . Sur la base de ces résultats les propriétés spectrales et magnétiques précédemment obtenues peuvent être expliquées. L'existence d'une forte interaction directe molybdène-molybdène dans le coeur Mo2O 4 2+ est clairement démontrée.相似文献
66.
Leszek Czuchajowski Stefan Goszczynski Dale E. Wheeler Antoni K. Wisor Tadeusz Malinski 《Journal of heterocyclic chemistry》1988,25(6):1825-1830
(R + S)Meso-[2.2]Paracyclophanyltriphenylporphyrin 3 , a member of a novel class of cyclophanylporphyrins, was obtained and characterized by spectroscopic and electrochemical methods. Compared to meso-tetra[2.2]paracyclophanylporphyrin 1, it represents a simplified structure designed for the investigation of electronic interactions between the [2.2]paracyclophane moiety and porphyrin core and for use in metallation reactions. 相似文献
67.
The combined CNDO/S and transition density matrix methods reproduced well the UV-VIS spectra of the intramolecular charge-transfer complexes of double- and triple-layered [2.2]paracyclophanequinones in which benzene and p-benzoquinone represent the donor and acceptor layers: DA, DDA and DAD. Calculations pointed to the already known experimental bathochromic shifts of the longest wavelength absorption band for the DADDADAD transformations. The electronic transitions corresponding to this band are for DA and DDA the CT transitions of the
* type; however, for DAD the band represents the n
* transition localized on the acceptor ring. 相似文献
68.
Karol Jankowski Janina Muszyńska Andrzej Rutkowski 《Theoretical chemistry accounts》1978,47(4):275-282
The Galerkin-Petrov method is applied to the determination of the ground state energy of the beryllium atom. The basis set of the coordinate subspace consists of correlated wavefunctions of the combined configuration-interaction-Hylleraas type. The basis set of the projective subspace is of the configuration-interaction type. The usefulness of a previously proposed way of characterization of pairs of subspaces has been further confirmed. Experience in constructing close pairs of subspaces gathered in the case of two-electron systems is used for the larger system. Two methods for constructing pairs of subspaces are used in the calculations. 相似文献
69.
Herrebout WA Melikova SM Delanoye SN Rutkowski KS Shchepkin DN van der Veken BJ 《The journal of physical chemistry. A》2005,109(13):3038-3044
Mid-infrared spectra of mixed solutions in liquid xenon containing fluoroform and either ammonia or pyridine have been investigated at temperatures between 173 and 213 K. For both Lewis bases, a new band is found in the CH stretching region at a frequency approximately 5 cm(-1) higher than that of monomer fluoroform, which is assigned to a complex between fluoroform and the Lewis base. A detailed analysis of the nu1/2nu(4) Fermi resonance in the proton donor shows that the blue shifts observed for the complexes are not caused by a strengthening of the CH bond during the complexation, but are due to the changes in the Fermi resonance interactions. Information on the nu1/2nu(4) Fermi resonance was also obtained for the complexes of fluoroform with dimethyl ether and trimethyl amine. 相似文献
70.