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21.
A reaction condition is established which determines the nature of the products in the molybdate-hydroxylamine-cyanide reaction. With hydroxylamine always used in excess, it is the hydroxyl ion concentration of the reaction mixture which plays a vital role in determining whether K4[Mo(NO)(CN)5] or K2[Mo(NO)(CN)5] is obtained exclusively. The latter product is hereby reported for the first time. Its powder diffractogram being typical of a cubic system, a gross structural characterization has been made possible. The former under aqueous, aerobic conditions yields a new product, (NMe4)2[Mo(NO)(CN)4]. 相似文献
22.
C. T. Zhang M. Sferrazza R. H. Mayer Z. W. Grabowski P. Bhattacharyya P. J. Daly R. Broda B. Fornal W. Królas T. Pawłat G. de Angelis D. Bazzacco S. Lunardi C. Rossi-Alvarez 《Zeitschrift für Physik A Hadrons and Nuclei》1995,351(1):11-12
Using an 11.4MeV/u136Xe beam of the UNILAC accelerator of GSI and anatW target, A=184 isobars were produced and separated by using an on-line mass separator. A new isomeric state was found in184Hf. This state decays with a half-life of 48(10) s and emits three -rays of 73, 482, and 555 keV as well as lower-lying cascade transitions. The hindrance of the 73 keV-E1 transition with K=8 is compared with those of other even-even hafnium isotopes. The half-life of184Lu was estimated to be between 15 and 25s. 相似文献
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25.
Shuvendu S. Bhattacharyya Bandana Mandal A. K. Das 《Fresenius' Journal of Analytical Chemistry》1996,355(2):180-182
An electrothermal atomic absorption spectrometric method is described for the determination of manganese in various coal fly ash samples after its separation with dissolved monothioxo--diketone as chelating ion exchanger. The detection limit is 1 ngml-1. To study the accuracy of the method, a reference material of similar composition was analysed and recovery of spiked manganese was performed. 相似文献
26.
Ab initio supermolecular SCF calculations at the STO-3G level are reported for the diacetylene-hydrogen fluoride complexes. The reverse
σ-complex is predicted to have somewhat higher stability and H-bond strength than the π-complexes. 相似文献
27.
A procedure is tested for directly calculating exciation energies for spin-conserving and spin-forbidden transitions using a spin-adapted coupled-cluster based linear response theory. The excited states are generated from the ground state through an excitation operator S, a combination of various nh—np excitations of spin-rank zero and one for singlet and triplet excitations. 相似文献
28.
S. Bhattacharyya A. N. Sil T. K. Mukherjee P. K. Mukherjee P. Vasu 《International journal of quantum chemistry》2007,107(4):946-951
Electron affinity of plasma embedded muonium (μ+e?) and pionium (π+e?) has been estimated using a general three‐body formalism within variational framework. Electron correlation is taken care of using extended Hylleraas basis sets. The stability of the three‐body systems have been studied under the Debye screening model of the plasma, which changes the Coulombic potential to the screened Coulomb one. The electron affinity of the muonium and pionium is maximum for free systems, and it decreases gradually toward zero with increase of the plasma strength, which tends to push the three‐body system toward gradual instability. The electron correlation contribution to the affinity has been analyzed. © 2006 Wiley Periodicals, Inc. Int J Quantum Chem, 2007 相似文献
29.
We show that two simple semiclassical strategies, one based on the Wilson–Sommerfeld rule and the other on the uncertainty principle, yield the exact modified form of the virial theorem for confined systems. An alternative, easier quantum mechanical route to arrive at this result is also sketched. Pilot calculations on confined oscillators reveal decisive trends. © 2004 Wiley Periodicals, Inc. Int J Quantum Chem, 2005 相似文献
30.
Bhattacharyya S Fan L Vo L Labadie J 《Combinatorial chemistry & high throughput screening》2000,3(2):117-124
Amine libraries and their derivatives are important targets for high throughput synthesis because of their versatility as medicinal agents and agrochemicals. As a part of our efforts towards automated chemical library synthesis, a titanium(IV) isopropoxide mediated solution phase reductive amination protocol was successfully translated to automation on the Trident(TM) library synthesizer of Argonaut Technologies. An array of 24 secondary amines was prepared in high yield and purity from 4 primary amines and 6 carbonyl compounds. These secondary amines were further utilized in a split synthesis to generate libraries of ureas, amides and sulfonamides in solution phase on the Trident(TM). The automated runs included 192 reactions to synthesize 96 ureas in duplicate and 96 reactions to synthesize 48 amides and 48 sulfonamides. A number of polymer-assisted solution phase protocols were employed for parallel work-up and purification of the products in each step. 相似文献