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51.
Shruti A. Dubey 《Journal of Mathematical Analysis and Applications》2011,376(1):275-281
This paper discusses nonlinear functional differential equation in a real reflexive Banach space with nonlocal history condition. By using the method of lines, the existence and uniqueness of a strong solution are established. Finally, some applications of the abstract results are presented. 相似文献
52.
Reduction of ketone 3 derived from (R)-2,3-cyclohexylideneglyceraldehyde 1 with some common hydrides took place with syn-selectivity. The resulting major product 4a has been exploited as a common chiral template to prepare both enantiomers Ia,b of disparlure. 相似文献
53.
Nathan W. Polaske Ramin Dubey Gary S. Nichol Bogdan Olenyuk 《Tetrahedron: Asymmetry》2009,20(23):2742-2750
The asymmetric organocatalytic α-sulfenylation of substituted piperazine-2,5-diones is reported, with cinchona alkaloids as chiral Lewis bases and electrophilic sulfur transfer reagents. Catalyst loadings, the type of sulfur transfer reagent, temperature, and solvent were investigated in order to optimize the reaction conditions. The effects of ring substitution and the type of catalyst on the yield and enantioselectivity of the reaction are reported. 相似文献
54.
Vinay K. Singh Rahul Dubey Abhishek Upadhyay Laxmi Kant Sharma Rana Krishna Pal Singh 《Tetrahedron letters》2017,58(45):4227-4231
An efficient and economical method was developed for synthesis of 3-substituted indole by using electrochemically induced condensation of various aldehyde, indole and malononitrile. 相似文献
55.
In this paper, multilayer structures of porous silicon were fabricated by using electrochemical etching and characterized for its optical properties and surface morphology. Samples of monolayer of porous silicon were grown to study the characteristics of porous layer formation with respect to applied current density, etching time and hydrofluoric acid concentrations. Photoluminescence peaks of red emission at wavelength 695 and 650 nm were observed from multilayer porous silicon structures. By atomic force microscopy measurement, hillocks like surface were clearly observed within the host material, which confirmed the formation of pores. 相似文献
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58.
Srinivas Pasikanti D. Srinivasa Reddy P.K. Dubey Parthasarathi Das 《Tetrahedron letters》2010,51(1):151-152
Synthesis of varenicline the antismoking drug has been achieved in six steps with 10% overall yield. A Diels-Alder reaction, oxidative cleavage of an olefin and reductive amination remain as key steps in the synthesis 相似文献
59.
Prashant Dubey Devarajan Muthukumaran Subhashis Dash Rupa Mukhopadhyay Sabyasachi Sarkar 《Pramana》2005,65(4):681-697
Carbon nanotubes (CNT) has been synthesized by pyrolysing mustard oil using an oil lamp. It was made water-soluble (wsCNT)
through oxidative treatment by dilute nitric acid and was characterized by SEM, AFM, XRD, Raman and FTIR spectroscopy. The
synthesized wsCNT showed the presence of several junctions and defects in it. The presence of curved graphene structure (sp2) with frequent sp3 hybridized carbon is found to be responsible for the observed defects. These defects along with the presence of di- and tri-podal
junctions showed interesting magnetic properties of carbon radicals formed by spin frustration. This trapped carbon radical
showed ESR signal in aqueous solution and was very stable even under drastic treatment by strong oxidizing or reducing agents.
Oxidative acid treatment of CNT introduced several carboxylic acid group functionalities in wsCNT along with the nicking of
the CNT at different lengths with varied molecular weight. To evaluate molecular weights of these wsCNTs, an innovative method
like gel electrophoresis using high molecular weight DNA as marker was introduced. 相似文献
60.
We revisit the well-known topics of self- and induced-screening in an otherwise isotropic neutral plasma/colloid. It is pointed out that the standard Debye-Hückel (DH) theory (ignoring finite size effects) suffers from many ambiguities related to net ionic numbers, total charge of the system, role of the electrostatic Gauss law, short-distance behaviour of the potential and incorrectly normalized pair correlation functions. We give a new formulation (incorporating finite size effects) such that ionic numbers are maintained, the total charge of the system has physically correct value, the Gauss law boundary conditions are rigorously obeyed, short-distance behaviour of the potential is guaranteed automatically, and correlation functions are correctly normalized. Numerical differences between the two approaches show up if the screening length μ−1 becomes comparable to the size R of the system. 相似文献