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121.
Lipciuc ML Rakitzis TP Meerts WL Groenenboom GC Janssen MH 《Physical chemistry chemical physics : PCCP》2011,13(18):8549-8559
In this paper we report slice imaging polarization experiments on the state-to-state photodissociation at 42,594 cm(-1) of spatially oriented OCS(v(2) = 1|JlM = 111) → CO(J) + S((1)D(2)). Slice images were measured of the three-dimensional recoil distribution of the S((1)D(2)) photofragment for different polarization geometries of the photolysis and probe laser. The high resolution slice images show well separated velocity rings in the S((1)D(2)) velocity distribution. The velocity rings of the S((1)D(2)) photofragment correlate with individual rotational states of the CO(J) cofragment in the J(CO) = 57-65 region. The angular distribution of the S((1)D(2)) velocity rings are extracted and analyzed using two different polarization models. The first model assumes the nonaxial dynamics evolves after excitation to a single potential energy surface of an oriented OCS(v(2) = 1|JlM = 111) molecule. The second model assumes the excitation is to two potential energy surfaces, and the OCS molecule is randomly oriented. In the high J region (J(CO) = 62-65) it appears that both models fit the polarization very well, in the region J(CO) = 57-61 both models seem to fit the data less well. From the molecular frame alignment moments the m-state distribution of S((1)D(2)) is calculated as a function of the CO(J) channel. A comparison is made with the theoretical m-state distribution calculated from the long-range electrostatic dipole-dipole plus quadrupole interaction model. The S((1)D(2)) photofragment velocity distribution shows a very pronounced strong peak for S((1)D(2)) fragments born in coincidence with CO(J = 61). 相似文献
122.
Dilute gas viscosity data may be inverted directly to give the intermolecular potential energy function if the well depth is known. The consequences of using different values of the well depth are studied, and it is concluded that the correct value may be distinguished by using second virial coefficient data. 相似文献
123.
Maurice Rigby 《Molecular physics》2013,111(2):575-578
Applications of the method of anti-symmetrized product of strongly orthogonal geminals (APSG) to the boron hydrides B2H6, B4H4, B4H10, B5H9, B5H11 and B6H10 are described. Minimal basis sets of Slater-type orbitals are employed throughout. The APSG method is found to act as a localization process, with the B-H (terminal) and B-H (bridge)-B geminals well localized and transferable. Generation of several valence structures for B5H9, B5H11 and B6H10 suggests that the framework geminals of the preferred structure are of the closed three-centre type, although structures involving open BBB framework geminals are less stable by only a few kcal mol-1. The principal natural orbital of each geminal is similar to the corresponding orbital produced by various localization criteria, while the weakly occupied natural orbitals are also localized and involve anti-bonding interactions between the component atoms of the bond. 相似文献
124.
The technique of phase-measuring profilometry is reviewed, whereby a sinusoidal grating structure is projected onto a diffuse three-dimensional surface, and the resulting deformed grating image is detected by a solid state array camera and processed by a microcomputer using interferometric phase measuring algorithms. The approach permits parallel acquisition and processing of large amounts of data with high accuracy and speed.Several systems are described, configured with telecentric laser light illumination or general white light diverging illumination, and capable of measurement from a single point of view or over full 360°. Each system consists of an optical projection assembly with phase-shifter, an imaging assembly with high density CCD camera and an IBM AT microcomputer with buffer and control cards.Applications to industrial inspection and medical diagnostics are presented. 相似文献
125.
Structure of a simple scheduling polyhedron 总被引:5,自引:0,他引:5
Maurice Queyranne 《Mathematical Programming》1993,58(1-3):263-285
126.
Five butane-2,3-diacetals obtained from the reaction of 1,2-diols and methanol with biacetyl have been treated with allylsilane in the presence of titanium tetrachloride to afford bis-allyldioxanes as single diastereoisomers. 相似文献
127.
Octaethyltetraoxaporphyrin-Dikation – Pendant des Octaethylporphyrins in der Tetraoxaporphyrin-Reihe
128.
Maurice J. Marks Nikhil E. Verghese K. James Hrovat Anamari Laboy‐Bollinger James C. Buck James A. Rabon Jr. Carol L. O'connell Lisa Allen 《Journal of Polymer Science.Polymer Physics》2008,46(15):1632-1640
Five families of new controlled epoxy thermosets (CENs) using three monophenol chain terminators were prepared to study systematic changes in the structure and amount of the monophenol and the initial molecular weight between crosslinks (Mc,i) on the properties of epoxy thermosets. Glass transition temperature (Tg) decreases with monophenol mole fraction (χ) in proportion to both the concentration and flexibility of the chain terminator. Distinct serial relations for Tg depression were observed for the three Mc,i families. Dynamic mechanical analysis (DMA) shows significant perturbations of the relaxation behavior with added terminator as evidenced by decrease in peak tan δ and in post Tg damping. The rubbery coefficients of thermal expansion (CTE) increases with monophenol concentration only at χ > 0.05 and shows distinct curvature versus temperature, but is largely invariant with monophenol flexibility. The thermal stability of terminated CENs decreases only slightly with χ and little difference was found with monophenol structure. Most surprisingly, fracture toughness decreases markedly and discontinuously with χ depending on Mc,i. The values of the critical monophenol concentration at which fracture toughness markedly decreases (χc) are inversely proportional to Mc,i but are independent of monophenol flexibility. No correlation of χc with any of the calculated network structure parameters was apparent. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 1632–1640, 2008 相似文献
129.
David Rosenthal Frederick R. Hopf David G. Whitten Maurice M. Bursey 《Journal of mass spectrometry : JMS》1973,7(4):497-499
The ruthenium porphyrin carbonyl (I) reacts with perfluorokerosene and perfluorotributylamine to give ions of the type [M – CO + CnF2n], n = 1 to 4. 相似文献
130.
Jerry S. Kelly Wulf Gaertner Prasanta J. Pattanaik Maurice Salles 《Journal of Elasticity》1989,21(1):v-v
Editorial announcement 相似文献