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991.
A. Banerjee S. B. Duttachoudhury Abhik Kumar Sanyal 《General Relativity and Gravitation》1986,18(5):461-477
A spatially homogeneous and locally rotationally symmetric Bianchi type-II cosmological model under the influence of both shear and bulk viscosity has been studied. Exact solutions are obtained with a barotropic equation of state (p=) and considering the linear relationships between, 2, and 2, which represent the fluid density, the expansion, and the shear scalars, respectively. Special cases with vanishing bulk viscosity coefficients and with the perfect fluid in the absence of viscosity have also been studied. The formal appearance of the solutions is the same for both the viscous as well as the perfect fluids. The difference is only in choosing a constant parameter which appears in the solutions. In the cases of either a fluid with bulk viscosity alone or a perfect fluid, the barotropic equation of state is no longer an additional assumption to be imposed; rather it follows directly from the field equations. 相似文献
992.
The Gibbs free energy of formation of CaRh2O4(s) has been determined using two techniques viz., quadrupole mass spectrometer coupled to a Knudsen cell and solid-state cell incorporating CaF2(s) as the solid electrolyte. In the former method, equilibrium O2(g) pressures were measured over the phase field Rh(s)+Rh2O3(s), in the temperature range 793.7-909.1 K and over the three phase mixture CaRh2O4(s)+Rh(s)+CaO(s) was measured from 862.1 to 1022.7 K.The Gibbs free energy of formation of Rh2O3(s) from elements in their standard state can be given by
993.
Anuradha Dhur Sarmistha Das R. N. Banerjee D. Banerjea 《Transition Metal Chemistry》1982,7(2):125-127
Summary The kinetics of dissociation of glycinepentaamminecobalt(III) and tetraaquomonoacetylacetonatochrormium(III) ions in moderately strong perchloric acid media have been investigated spectrophotometrically. From the dependence of the rate on various acidity functions and the observed isokinetic and free energy relationships, both the complexes appear to react by an associative process involving interaction of the conjugate acid form of the substrate complex and H3O+. 相似文献
994.
Alexopoulos T Allen C Anderson EW Areti H Banerjee S Beery PD Biswas NN Bujak A Carmony DD Carter T Cole P Choi Y De Bonte R Erwin A Findeisen C Goshaw AT Gutay LJ Hirsch AS Hojvat C Kenney VP Koltick D Lindsey CS LoSecco JM McMahon T McManus AP Morgan N Nelson K Oh SH Piekarz J Porile NT Reeves D Scharenberg RP Stringfellow BC Stampke SR Thompson M Turkot F Walker WD Wang CH Wesson DK 《Physical review letters》1988,60(16):1622-1625
995.
E. G. Baburaj G. E. Prasad S. Banerjee T. Raghu M. J. Patni 《Journal of Thermal Analysis and Calorimetry》1995,44(2):345-352
Amorphous to crystalline transformation in Cu60Ti40 alloy has been studied under conditions of constant heating rate experiments, using XRD and DSC. In the high temperature XRD experiment, the transformation has been monitored continuously as the integrated X-ray intensity corresponding to a chosen reflection from one of the two crystalline products forming at close by temperatures. Differentiation of the curve thus obtained gives the transformation rate curve which passes through a maximum. From the peak shift with heating rate, the activation energy for the formation of Cu3Ti2 crystalline phase has been obtained. The results have been compared with those obtained by DSC. 相似文献
996.
Employing48Ca as the core, the structure of51V is studied in the framework of a conventional shell-model. A pairing-plus-surface-tensor-interaction is used as the effective
two-body interaction. Besides all configurations arising from 1f
7/2 and 2p
3/2 single-particle orbits, configurations of the form
wheren
1+n
2=3 (the number of extracore protons) andn
2 = 1, 2 are also considered. Low-lying energy levels are calculated and a satisfactory agreement with the experimental values
is obtained. Our calculated density of states is higher than that reported previously. We also present theB(E2) values for transitions between low-lying levels and the spectroscopic factors for the50Ti (3He, d)51V reaction. The dependence of the interaction parameters on the mass number of the core nucleus is also studied. 相似文献
997.
Asymmetric Modulation of Protein Order–Disorder Transitions by Phosphorylation and Partner Binding 下载免费PDF全文
Priya R. Banerjee Diana M. Mitrea Richard W. Kriwacki Ashok A. Deniz 《Angewandte Chemie (International ed. in English)》2016,55(5):1675-1679
As for many intrinsically disordered proteins, order–disorder transitions in the N‐terminal oligomerization domain of the multifunctional nucleolar protein nucleophosmin (Npm‐N) are central to its function, with phosphorylation and partner binding acting as regulatory switches. However, the mechanism of this transition and its regulation remain poorly understood. In this study, single‐molecule and ensemble experiments revealed pathways with alternative sequences of folding and assembly steps for Npm‐N. Pathways could be switched by altering the ionic strength. Phosphorylation resulted in pathway‐specific effects, and decoupled folding and assembly steps to facilitate disorder. Conversely, binding to a physiological partner locked Npm‐N in ordered pentamers and counteracted the effects of phosphorylation. The mechanistic plasticity found in the Npm‐N order–disorder transition enabled a complex interplay of phosphorylation and partner‐binding steps to modulate its folding landscape. 相似文献
998.
Slow Molecular Motions in Ionic Liquids Probed by Cross‐Relaxation of Nuclear Spins During Overhauser Dynamic Nuclear Polarization 下载免费PDF全文
Dr. Abhishek Banerjee Arnab Dey Prof. Dr. Narayanan Chandrakumar 《Angewandte Chemie (International ed. in English)》2016,55(47):14756-14761
Solution‐state Overhauser dynamic nuclear polarization (ODNP) at moderate fields, performed by saturating the electron spin resonance (ESR) of a free radical added to the sample of interest, is well known to lead to significant NMR signal enhancements in the steady state, owing to electron–nuclear cross‐relaxation. Here it is shown that under conditions which limit radical access to the molecules of interest, the time course of establishment of ODNP can provide a unique window into internuclear cross‐relaxation, and reflects relatively slow molecular motions. This behavior, modeled mathematically by a three‐spin version of the Solomon equations (one unpaired electron and two nuclear spins), is demonstrated experimentally on the 19F/1H system in ionic liquids. Bulky radicals in these viscous environments turn out to be just the right setting to exploit these effects. Compared to standard nuclear Overhauser effect (NOE) work, the present experiment offers significant improvement in dynamic range and sensitivity, retains usable chemical shift information, and reports on molecular motions in the sub‐megahertz (MHz) to tens of MHz range—motions which are not accessed at high fields. 相似文献
999.
Banerjee M Vyas VS Lindeman SV Rathore R 《Chemical communications (Cambridge, England)》2008,(16):1889-1891
A practical synthesis of 1,3,6,8-tetraisopropylpyrene and the isolation and X-ray structural characterization of its monomeric cation radical salt are described. 相似文献
1000.
Banerjee S Sen S Mitra S Rizzoli C Rosair GM 《Dalton transactions (Cambridge, England : 2003)》2008,(13):1783-1786
The aerial oxidation of cobalt(II) salt, in a methanolic solution, containing a hydrazone ligand, (E)-N'-(4-oxo-4-phenylbutan-2-ylidene)benzohydrazide (condensation product of benzoyl acetone and benzhydrazide, LH2) leads to the coupling of two such ligand units through the formation of a rather long C-C bond [1.601(6) A] giving rise to a dinuclear Co (III) hydrazone complex, [Co2(L)2(L')(].0.25H2O (L' = C-C coupled hydrazone ligand). The structure of the complex has been determined by X-ray crystallography and IR, UV-Vis spectroscopy and elemental analysis have characterized the complex. 相似文献