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91.
L. V. Rybin S. V. Osintseva A. S. Batsanov Yu. T. Struchkov P. V. Petrovskii M. I. Rybinskaya 《Russian Chemical Bulletin》1993,42(7):1228-1235
The thermal reactions of Ru3(CO)12 with RCOCH=CHPh (R=Me, p-MeC6H4) in hydrocarbon solvents lead to the formation of a series of complexes, several of which have been isolated as individual compounds by chromatography. The dinuclear complex Ru2(-H)(CO)6(-MeCOCH=CPh) and the tetranuclear complex Ru4(-H)(-CO)(CO)7(p-MeC
6H4 COCH=CPh)(-p-MeC6H4COCH=CPh)(4-p-MeC6H3COCH=CHPh) are characterized by an X-ray structural study. The structures of other reaction products are discussed on the basis of spectral data. The reactions are accompanied by reduction of the starting enones to the corresponding unsaturated ketones.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1285–1293, July, 1993. 相似文献
92.
《数学研究通讯:英文版》2016,(4):325-331
In this paper, we consider the problem of determining the order of INAR(q) model on the basis of the Bayesian estimation theory. The Bayesian es-timator for the order is given with respect to a squared-error loss function. The consistency of the estimator is discussed. The results of a simulation study for the estimation method are presented. 相似文献
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95.
Simone Madama Ermelinda Falletta Amir Mohammad Malvandi Kevin Arzoni Carlo Brogna Marco Varelli Matteo Bertelli Matteo Conti Martina Larini Federico Guidugli Pietro Traldi Simone Cristoni 《Journal of mass spectrometry : JMS》2022,57(8):e4876
In this work, the isolation step in the linear ion trap was performed using different “q values” conditions at a low collision-induced dissociation (CID) energy leading to the parent ion resolution improvements, reasonably due to better ion energy distribution. According to the results, we obtained a greater resolution and mass accuracy operating in both traditional electrospray and low voltage ionization near the q value = 0.778 and with a CID energy of 10%. This effect was evaluated with low-molecular-mass compounds (skatole and arginine). The proposed optimization yielded a superior instrument performance without adding technological complexity to mass spectrometry analyses. 相似文献
96.
This paper presents a formulation of isothermal three-dimensional (3D) quasi-static magneto-mechanical constitutive equations and 3D magnetisation constitutive equations for tetragonal martensite Ni–Mn–Ga FSMA single crystals (c/a<1) with both ends restrained from twin-boundary motion. The formulated 3D constitutive equations model the 3D quasi-static magnetic fields as well as the coupling between uniaxial strains and stresses, and shear strains and stresses. The constitutive equations are compared with experimental results available in the literature and are found to correlate well with the experimental results, including magnetic field reversals. Both sets of 3D constitutive equations require only macroscopic parameters that are readily obtainable from magnetisation and mechanical stress–strain curves. 相似文献
97.
The currently operating X-ray imaging observatories provide us with an exquisitely detailed view of the Megaparsec-scale plasma atmospheres in nearby galaxy clusters. At z<0.05, the Chandra 's 1″ angular resolution corresponds to linear resolution of less than a kiloparsec, which is smaller than some interesting linear scales in the intracluster plasma. This enables us to study the previously unseen hydrodynamic phenomena in clusters: classic bow shocks driven by the infalling subclusters, and the unanticipated “cold fronts,” or sharp contact discontinuities between regions of gas with different entropies. The ubiquitous cold fronts are found in mergers as well as around the central density peaks in “relaxed” clusters. They are caused by motion of cool, dense gas clouds in the ambient higher-entropy gas. These clouds are either remnants of the infalling subclusters, or the displaced gas from the cluster's own cool cores. 相似文献
98.
This paper addresses a construction of new q‐Hermite polynomials with a full characterization of their main properties and corresponding raising and lowering operator algebra. The three‐term recursive relation as well as the second‐order differential equation obeyed by these new polynomials are explicitly derived. Relevant operator actions, including the eigenvalue problem of the deformed oscillator and the self‐adjointness of the related position and momentum operators, are investigated and analyzed. The associated coherent states are constructed and discussed with an explicit resolution of the induced moment problem. The phase collapse in a q‐deformed boson system is studied. 相似文献
99.
Neuraminidase is a significant anti‐influenza target that plays crucial role in virus replication cycle. The discovery of 150‐cavity in Group‐1 neuraminidase provides us a novel mentality of designing inhibitor which can bind with both conserved site and 150‐cavity. In order to discover novel dual‐site‐binding inhibitors, a 3D chemical‐feature‐based pharmacophore model was established to cover dual‐site in neuraminidase. The dual‐site‐binding model was consistent in predicting the binding conformation of Group‐1 neuraminidase inhibitor and applied for virtual screening of Specs database. Compound 4 (ZINC05790048) that aligned well to the model was selected after multiple filtrations for molecular dynamics simulations, indicating improved binding energy with neuraminidase. It can sever as the lead compound for a novel series of inhibitors. 相似文献
100.
We consider the effect of a variable representing the competition between the frequency of the field and the frequency of the spin flipping (Ω) on the dynamics of the metamagnetic Ising model in a cubic lattice under the presence of a time varying (oscillating) external magnetic field. The system is modelled with a formalism of master equation at a mean-field level. The time averaged staggered magnetization (Ms) acts as the order parameter and divides temperature field plane into three regions: anti-ferromagnetic, paramagnetic and coexistence of anti-ferromagnetic and paramagnetic phases. It is observed that the topology of the dynamical phase diagram depends strongly on Ω as well as the ratio between interlayer and intralayer couplings. 相似文献