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471.
Ilia A. Guzei Robert W. McGaff Heidi M. Kieler 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(11):m472-m475
The square‐pyramidal Mg center in the title compound, [Mg(C32H16N8)(CH4O)], is five‐coordinate due to the formation of back‐to‐back π–π dimers that saturate the vacant apical site of the metal coordination sphere. Each complex is a member of a back‐to‐back and a face‐to‐face dimer; the latter are tethered by two strong O—H⋯N hydrogen bonds. The dimers form columns that likely determine the solid‐state packing. The phthalocyaninate ligands are essentially planar, with a slight `hat visor' conformation character. 相似文献
472.
Andreea Micle Natalia Miklova Richard A. Varga Aurelia Pascariu Nicoleta Pleu Mihaela Petric Gheorghe Ilia 《Tetrahedron letters》2009,50(40):5622-5624
The iminophosphorane CH2CH2[P{NP(O)(OPh)2}Ph2]2 is synthesized in high yields (80–97%) via a very convenient procedure using diphenylphosphoryl azide (DPPA) and 1,2-bis(diphenylphosphino)ethane. 相似文献
473.
Ilia A. Guzei Robert A. Stockland Richard F. Jordan 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(6):635-636
The title complex, [Zr(CH3)(C5H5)2][CH3B(C6F5)3], crystallizes as an ion pair linked through an unsymmetrical methyl bridge. The bridging Zr—Me distance [2.556 (2) Å] is significantly longer than the terminal Zr—Me distance [2.251 (3) Å], while the Zr—C—B angle approaches linearity [169.1 (2)°]. 相似文献
474.
Ilia A. Guzei Letladi L. Maisela James Darkwa 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(5):564-565
The Pd atom in the title compound, [Pd(C6H5S)2(C22H36FeP2)], possesses a distorted square‐planar geometry. The phenyl rings attached to the S atoms are located on opposite sides of the plane defined by the Pd and two S atoms. The Pd—S bonds are statistically significantly different, with values of 2.3703 (7) and 2.3887 (7) Å. 相似文献
475.
Wim Van Paepegem Assen A. Shulev Ilia R. Roussev Stijn De Pauw Joris Degrieck Ventseslav C. Sainov 《Optics and Lasers in Engineering》2009,47(3-4):390-397
This paper presents a speckle-displacement measurement technique based on the digital image correlation to study the notch sensitivity and crack bridging of window security film. It is used to protect existing glazing against hurricanes, blast and terrorist explosions. The window security film is laminated to the interior side of the glass window by means of a special adhesive. When the glass is breaking, the window film keeps all glass fragments together.The proposed sub-pixel registration of the displacement field is achieved using a calculation technique based on the centre of mass localization of the complex spectrum. This approach increases the computational efficiency for displacements smaller than one pixel and performs with high precision when optimal values of the input correlation parameters are used. In order to achieve a high accuracy of the algorithm, optimization of these input image correlation parameters is offered. For larger displacements an iterative procedure which preserves the precision is successfully implemented.The speckle pattern is created by small white dots sprayed on the previously black painted film surface. As a result, white light illumination can be used which significantly simplifies the experiments. 相似文献
476.
We consider extensions of the next-to-minimal supersymmetric model (NMSSM) in which the observed neutrino masses are described in terms of effective dimension six (or seven) rather than dimension five operators. All such operators respect the discrete symmetries of the model. The new particles associated with the double (or triple) seesaw mechanism can have sizable couplings to the known leptons, even with a TeV seesaw scale. In the latter case some of these new short-lived particles could be produced and detected at the LHC. 相似文献
477.
Sergey G. Il'yasov Vera S. Glukhacheva Valentina A. Yermoshina Ilia V. Eltsov 《无机化学与普通化学杂志》2019,645(11):792-796
Nitro compounds of octaaza derivatives of reduced anthracene were synthesized for the first time by reaction of 2,3,4a,6,7,8a,9,10‐octaaza‐4,8‐dioxo‐3,4,4a,7,8,8a,9,9a,10,10a‐decahydroanthracene with nitric acid, mixed nitric acid/sulfuric acid, and nitric acid/acetic anhydride at between –20 and –30 °C. In addition, 1,2,4,5‐tetrazine azido derivatives were obtained by hydrolytic decomposition of the starting compound by nitrous acid. All the resultant compounds exhibit high thermal stability. 相似文献
478.
Dissociation Energy Computations for Saline Bonds Implied in Interactions Mediated by Peptidoglicans
Simona Muntean Ludovic Kurunczi Cristian Bologa Gheorghe Ilia Zeno Simon 《Macromolecular Symposia》2006,235(1):215-219
Summary: Dissociation energy and hydration energy calculations, in water solution, are presented for saline bonds mediated by Ca2+ and Mg2+ ions with Brőnstedt type bases ( COO , OSO3 , OH). A computationally intensive method, Polarisable Continuum Model (PCM) using 6-31G* basis set, was applied. Hydration energies were computed by various methods, as well as dissociation energies of some L2M complexes. L2Ca complexes result as more stable against dissociation than L2Mg complexes. Hydration energy calculation results, for some of the methods, here used, seem rather reliable as compared to experimental results. 相似文献
479.
Ilia A. Guzei Catherine E. Radzewich Richard F. Jordan 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(3):279-281
The crystal structure of the title compound, [AlCl(CH3)‐(C15H13N2)][Li(C24BF20)]2·C6H6, is reported. The unusual coordination features of the lithium(I) cation, including Li‐atom coordination to six organohalogen atoms and the shortest Li—F(C) distances so far observed, are discussed. 相似文献
480.
Ilia A. Guzei Fabien Delpech Richard F. Jordan 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(8):e327-e328
The title complex, [In(CH3)(C18HBF15O)(C13H19N2)], crystallizes as an ion pair linked by a μ‐hydroxo bridge. There are two independent molecules in the asymmetric unit that exhibit essentially identical metric parameters, but different conformations. 相似文献