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91.
Ujjal Debnath Mubasher Jamil Surajit Chattopadhyay 《International Journal of Theoretical Physics》2012,51(3):812-837
In the framework of Fractional Action Cosmology (FAC), we study the generalized second law of thermodynamics for the Friedmann
Universe enclosed by a boundary. We use the four well-known cosmic horizons as boundaries namely, apparent horizon, future
event horizon, Hubble horizon and particle horizon. We construct the generalized second law (GSL) using and without using
the first law of thermodynamics. To check the validity of GSL, we express the law in the form of four different scale factors
namely emergent, logamediate, intermediate and power law. For Hubble, apparent and particle horizons, the GSL holds for emergent
and logamediate expansions of the universe when we apply with and without using first law. For intermediate scenario, the
GSL is valid for Hubble, apparent, particle horizons when we apply with and without first law. Also for intermediate scenario,
the GSL is valid for event horizon when we apply first law but it breaks down without using first law. But for power law expansion,
the GSL may be valid for some cases and breaks down otherwise. 相似文献
92.
93.
Mousa Al-Noaimi Mohammad El-khateeb Salim F. Haddad Haytham Saadeh 《Transition Metal Chemistry》2010,35(7):877-883
Abstract
Five ruthenium complexes bearing phenylazo-(2-(phenylthio))phenylmethine ligands of the general type trans-[RuII(bpy)(L)(Cl)2] (C1–C5) {L = YC6H4N=NC(COCH3)=NC6H4(2-SC6H5), H (L1), Cl (L2), OCH3 (L3), Br (L4), or NO2 (L5)} have been synthesized. The crystal structure of trans-[Ru(bpy)(L1)(Cl)2] (C1) is reported and shows no direct metal–S interaction. The complexes have been characterized through spectroscopic (IR, UV/vis and NMR) and electrochemical (CV) techniques. The electrochemical parameters (E L(L)) of the azoimine ligands are reported. 相似文献94.
M. Umar Farooq Mubasher Jamil Muneer A. Rashid 《International Journal of Theoretical Physics》2010,49(9):2278-2287
We consider the new agegraphic dark energy model with the help of the quantum corrections to the entropy-area relation in
the setup of loop quantum gravity. Employing this new form of dark energy so called entropy-corrected new agegraphic dark
energy (ECNADE), we investigate the model of interacting dark energy and derive its equation of state (EoS). We study the
correspondence between the K-essence, tachyon and dilaton scalar fields with the interacting (ECNADE)in the non-flat FRW universe.
Moreover, we reconstruct the corresponding scalar potentials which describe the dynamics of the scalar field. 相似文献
95.
Mubasher Jamil 《International Journal of Theoretical Physics》2010,49(1):62-71
I present a model in which dark energy interacts with matter. The former is represented by a variable equation of state. It
is shown that the phantom crossing takes place at zero redshift, moreover, stable scaling solution of the Friedmann equations
is obtained. I show that dark energy is most probably be either generalized phantom energy or the generalized Chaplygin gas,
while phantom energy is ruled out as a dark energy candidate. 相似文献
96.
Mubasher?Jamil 《International Journal of Theoretical Physics》2010,49(1):144
I present a model in which dark energy interacts with matter. The former is represented by a variable equation of state. It is shown that the phantom crossing takes place at zero redshift, moreover, stable scaling solution of the Friedmann equations is obtained. I show that dark energy is most probably be either generalized phantom energy or the generalized Chaplygin gas, while phantom energy is ruled out as a dark energy candidate. 相似文献
97.
Georges Dénès Jamil Hantash Abdualhafeed Muntasar Philip Oldfield Alan Bartlett 《Hyperfine Interactions》2006,170(1-3):145-158
Ionic conductors are solids that have a large number of defects and easy pathways that make it possible for ions to move over long distances in an electric field. In order to be mobile an ion must be small and have a low charge. The fluoride ion is the most mobile anion. The highest performance fluoride ion conductors contain divalent tin, and have a highly layered crystal structure related to the CaF2 fluorite type. BaSnF4 has the α-PbSnF4 structure, which is a √2/2?×?√2/2?×?2 superstructure of the fluorite type, where the tetragonal unit-cell and the value of the a and b parameters being equal to half the diagonals of the (a,b) face of fluorite are due to the loss of the F Bravais lattice, and the Sn Sn Ba Ba order along the c parameter is at the origin of the doubling of the c parameter. The BaSnF4 material was prepared first by Dénès et al. (C. R. Acad. Paris C, 280: 831, 1975), and its superionic properties were characterized by Dénès et al. (Solid State Ion., 13: 213, 1984). It was found to have a conductivity three orders of magnitude higher than that of BaF2, with an ionic conduction rate τ i?>?0.99. No BaSnF4 was obtained by the aqueous medium, when aqueous solutions of SnF2 and Ba(NO3)2 are mixed together; BaSn2F6 was obtained instead. In a new development of this work, BaSnF4 has been obtained by the wet method for the first time. X-ray powder diffraction showed that the BaSnF4 phase obtained by the wet method varies substantially from one sample to another: (a) signification variations of the c parameter of the tetragonal unit-cell reveals that the interlayer distance is sensitive to the leaching conditions, possibly because some of the leached ions remain in the interlayer spacing; (b) large variations of the crystallite dimensions and, as a result of the two-dimensionality of the structure, a strong crystallite dimension anisotropy are observed, with d∥?d⊥, where d∥ and d⊥ are the crystallite dimensions parallel to the four-fold main axis, and perpendicular to it, respectively, showing that the layers are very thin and the interlayer interactions are very weak. Variable temperature Mössbauer spectroscopy showed an unusual large variation of the quadrupole splitting with temperature. A tentative explanation based on unusually large bond angles has been proposed. 相似文献
98.
T. Kousksou A. Jamil S. Gibout Y. Zeraouli 《Journal of Thermal Analysis and Calorimetry》2009,96(3):841-852
This paper presents some results obtained by Differential Scanning Calorimetry (DSC) for characterizing the phase transition
within an emulsion. The dispersed substances are either hexadecane, octadecane, water or binary solution. A non-equilibrium
model taking into account the inter-phase heat transfer between the emulsifying medium and the dispersed droplet is proposed
and explains the main experimental features. 相似文献
99.
A direct method is described for the determination of molybdenum in mg amounts of organomolybdenum compounds by flame emission or atomic absorption spectrometry. Air/acetylene, air/hydrogen and dinitrogen oxide/acetylene flames were used. The emission of molybdenum oxide is found to be analytically useful in the hydrogen-based flames while the acetylene-based flames are better for atomic absorption. Various organomolybdenum compounds were analysed by both methods as well as by an alternative spectrophotometric method, with satisfactory agreement. The procedure involves simply dissolving the sample in a mixed solvent and aspirating the solution into the flame. 相似文献
100.
Recent developments in the transformation of biobased 5-hydroxymethylfurfural (HMF) into a potential liquid fuel, 2,5-dimethylfuran (DMF), are summarised. This review focuses briefly on the history of HMF conversion to DMF in terms of the feedstock used and emphasises the ideal requirements in terms of the catalytic properties needed in HMF transformation into DMF. The recent state of the art and works on HMF transformation into DMF are discussed in comparison to noble metals and non-noble metals as well as bimetallic catalysts. The effect of the support used and the reaction conditions are also discussed. The recommendations for future work and challenges faced are specified. 相似文献