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131.
In this paper we discuss the direct isotropic to chiral smectic-C phase transition on the basis of a phenomenological theory. The model free energy is written in terms of the coupled order parameters including the spontaneous polarization. We present a detailed analysis of the different phases that can occur and analyze the question under which conditions a direct isotropic to chiral smectic-C phase transition is possible when compared to other phase transitions. On the basis of this model the isotropic-smectic-C* transition is always of first order. The theoretical predictions are compared with the available experimental results.-1 相似文献
132.
C.?SurEmail author B. K.?Sahoo R. K.?Chaudhuri B. P.?Das D.?Mukherjee 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2005,32(1):25-31
We have employed the relativistic coupled cluster theory to calculate
the magnetic dipole and electric quadrupole hyperfine constants for
the ground and low lying excited states of singly ionized magnesium.
Comparison with experimental and the other theoretical results are
done and predictions are also made for a few low lying excited states
which could be of interest. We have made comparative studies of the
important many body effects contributing to the hyperfine constants
for the different states of the ion. 相似文献
133.
Valiente-Dobón JJ Steinhardt T Svensson CE Afanasjev AV Ragnarsson I Andreoiu C Austin RA Carpenter MP Dashdorj D de Angelis G Dönau F Eberth J Farnea E Freeman SJ Gadea A Garrett PE Görgen A Grinyer GF Hyland B Jenkins D Johnston-Theasby F Joshi P Jungclaus A Lieb KP Macchiavelli AO Moore EF Mukherjee G Napoli DR Phillips AA Plettner C Reviol W Sarantites D Schnare H Schumaker MA Schwengner R Seweryniak D Smith MB Stefanescu I Thelen O Wadsworth R 《Physical review letters》2005,95(23):232501
Three rotational bands in 74Kr were studied up to (in one case one transition short of) the maximum spin I(max) of their respective single-particle configurations. Their lifetimes have been determined using the Doppler-shift attenuation method. The deduced transition quadrupole moments reveal a modest decrease, but far from a complete loss of collectivity at the maximum spin I(max). This feature, together with the results of mean field calculations, indicates that the observed bands do not terminate at I = I(max). 相似文献
134.
We investigate the impact parameter-dependent parton distributions for a relativistic composite system in light-front framework. We express them in terms of overlaps of light-cone wave functions for a self-consistent two-body spin-
state, namely an electron dressed with a photon in QED. The pdf’s are distorted in the transverse space for transverse polarization of the state at one-loop level. 相似文献
135.
136.
Sonjoy?MajumderEmail author G.?Gopakumar R.?K.?Chaudhuri B.?P.?Das H.?Merlitz U.?S.?Mahapatra D.?Mukherjee 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2004,28(1):3-9
The relativistic coupled cluster theory is employed to calculate electric quadrupole (E2) transition probabilities among the doublet states of Mg II which are of interest in astrophysical problems. This is the first time a highly correlated fully ab initio method has been used to compute these quantities for this particular ion. The line strengths and transition probabilities of a number of different transitions are reported and compared with those available in the literature.Received: 4 June 2003, Published online: 30 September 2003PACS:
31.10. + z Theory of electronic structure, electronic transitions, and chemical bindingSonjoy Majumder: Present address: Institut für Theoretische Chemie, Technische Universität München, 85747 Garching, Germany. 相似文献
137.
Saha A Mukherjee AK 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2004,60(8-9):1731-1737
The formation of charge transfer (CT) complexes of 4-acetamidophenol (commonly called 'paracetamol') and a series of quinones (including Vitamin K3) has been studied spectrophotometrically in ethanol medium. The vertical ionisation potential of paracetamol and the degrees of charge transfer of the complexes in their ground state has been estimated from the trends in the charge transfer bands. The oscillator and transition dipole strengths of the complexes have been determined from the CT absorption spectra at 298 K. The complexes have been found by Job's method of continuous variation to have the uncommon 2:1 (paracetamol:quinone) stoichiometry in each case. The enthalpies and entropies of formation of the complexes have been obtained by determining their formation constants at five different temperatures. 相似文献
138.
Mukherjee M Kellerbauer A Beck D Blaum K Bollen G Carrel F Delahaye P Dilling J George S Guénaut C Herfurth F Herlert A Kluge HJ Köster U Lunney D Schwarz S Schweikhard L Yazidjian C 《Physical review letters》2004,93(15):150801
Mass measurements with a relative precision of better than 1.5 x 10(-8) were performed on 22Mg and its reaction partners 21Na and 22Na with the ISOLTRAP Penning trap mass spectrometer at CERN, yielding the mass excesses D(22Mg)=-399.92(27) keV, D(21Na)=-2184.71(21) keV, and D(22Na)=-5181.56(16) keV. The importance of these results is twofold. First, a comparative half-life (Ft value) has been obtained for the superallowed beta decay of 22Mg to further test the conserved-vector-current hypothesis. Second, the resonance energy for the 21Na proton capture reaction has been independently determined, allowing direct comparisons of observable gamma radiation in nova explosions with the yield expected from models. 相似文献
139.
Anita Majumdar Goutam Mukherjee 《Transactions of the American Mathematical Society》2004,356(6):2443-2457
It is well known that the Hochschild cohomology of an associative algebra admits a G-algebra structure. In this paper we show that the dialgebra cohomology of an associative dialgebra has a similar structure, which is induced from a homotopy G-algebra structure on the dialgebra cochain complex .
140.
Gharah N Chakraborty S Mukherjee AK Bhattacharyya R 《Chemical communications (Cambridge, England)》2004,(22):2630-2632
A combination of the newly synthesized and structurally characterized compound, [MoO(O2)2(saloxH)](saloxH2= salicylaldoxime) as catalyst, H2O2 as terminal oxidant and NaHCO3 as co-catalyst when stirred in CH3CN (10 cm3) at room temperature (rt) shows a very pronounced efficiency epoxidation of olefinic compounds, the method being green and economical. 相似文献