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81.
The present paper reports that TL glow curve and kinetic parameter of Eu3+ doped SrY2O4 phosphor irradiated by beta source. Sample was prepared by solid state preparation method. Sample was characterized by XRD analysis and particle size was calculated by Debye–Scherrer formula. The sample was irradiated with Sr-90 beta source giving a dose of 10 Gy and the heating rate used for TL measurements are 6.7 °C/s. The samples display good TL peaks at 106 °C, 225 °C and 382 °C. The corresponding kinetic parameters are calculated. The photoluminescence excitation spectrum at 247 and 364 nm monitored with 400 nm excitation and the corresponding emission peaks at 590, 612 and 624 nm are reported. 相似文献
82.
In this paper, we present an interactive decision support system for collecting and processing financial transit material for the Southeast Bank N.A. The underlying model is a bicriteria shortest path problem. The system provides a feasible solution in a matter of minutes, which provides the decision maker with an opportunity to perform “what if” analysis. The system can be extended to other vehicle routing problems with inventory components. 相似文献
83.
Summary The effect of surface mass flux on the non-Darcy natural convection over a horizontal flat plate in a saturated porous medium
is studied using similarity solution technique. Forchheimer extension is considered in the flow equations. The suction/injection
velocity distribution has been assumed to have power function form Bx
l
, similar to that of the wall temperature distribution Ax
n
, where x is the distance from the leading edge. The thermal diffusivity coefficient has been assumed to be the sum of the molecular
diffusivity and the dynamic diffusivity due to mechanical dispersion. The dynamic diffusivity is assumed to vary linearly
with the velocity component in the x direction, i.e. along the hot wall. For the problem of constant heat flux from the surface (n=1/2), similarity solution is possible when the exponent l takes the value −1/2. Results indicate that the boundary layer thickness decreases whereas the heat transfer rate increases
as the mass flux parameter passes from the injection domain to the suction domain. The increase in the thermal dispersion
parameter is observed to favor the heat transfer by reducing the boundary layer thickness. The combined effect of thermal
dispersion and fluid suction/injection on the heat transfer rate is discussed.
Received 7 December 1995; accepted for publication 7 January 1997 相似文献
84.
The method of similarity solution is used to study the influence of lateral mass flux and thermal dispersion on non-Darcy
natural convection over a vertical flat plate in a fluid saturated porous medium. Forchheimer extension is considered in the
flow equations and the coefficient of thermal diffusivity has been assumed to be the sum of molecular diffusivity and the
dispersion thermal diffusivity due to mechanical dispersion. The suction/injection velocity distribution has been assumed
to have power function form Ax
l
, where x is the distance from the leading edge and the wall temperature distribution is assumed to be uniform. When l=−1/2, similarity solution is possible, and the results indicate that the boundary layer thickness decreases where as the
heat transfer rate increases as the mass flux parameter passes from injection domain to the suction domain. The increase in
the thermal dispersion parameter is observed to enhance the heat transfer. The combined effect of thermal dispersion and fluid
suction/injection on the heat transfer rate is discussed.
Received on 9 September 1996 相似文献
85.
Post-sintering annealing effect on the diffuse phase transition in (Pb1−xBax)(Yb0.5Ta0.5)O3 ceramics
Dibyaranjan Rout K. Hariharan V.R.K. Murthy 《Journal of Physics and Chemistry of Solids》2005,66(5):809-816
The effect of post sintering annealing on the dielectric response of (Pb1−xBax)(Yb0.5Ta0.5)O3 ceramics in the diffuse phase transition range (x=0.2) has been investigated. The samples are prepared by conventional solid-state reaction method. The samples are sintered at 1300 °C for 2 h and annealed at different temperatures (800, 900 and 1000 °C) for 8 h and at 800 °C for different time durations (8, 12 and 24 h). A significant change in the dielectric response has been observed in all the samples. The dielectric constant increases remarkably and the dielectric loss tangent decreases. The dielectric peaks of the annealed samples are observed to be more diffused with noticeable frequency dispersion compared to the as sintered sample. 相似文献
86.
Due to the growing popularity of distributed computing systems and the increased level of modelling activity in most organizations, significant benefits can be realized through the implementation of distributed model management systems (DMMS). These systems can be defined as a collection of logically related modelling resources distributed over a computer network. In several ways, functions of DMMS are isomorphic to those of distributed database systems. In general, this paper examines issues viewed as central to the development of distributed model bases (DMB). Several criteria relevant to the overall DMB design problem are discussed. Specifically, this paper focuses on the problem of distributing decision models and tools (solvers), henceforth referred to as theModel Allocation Problem (MAP), to individual computing sites in a geographically dispersed organization. In this research, a 0/1 integer programming model is formulated for the MAP, and an efficient dual ascent heuristic is proposed. Our extensive computational study shows in most instances heuristic-generated solutions which are guaranteed to be within 1.5–7% of optimality. Further, even problems with 420 integer and 160,000 continuous variables took no more than 60 seconds on an IBM 3090-600E computer. 相似文献
87.
CoincidencePointsandCommonFixedPointsforCompatibleMapsofType(A)onSaksSpacesP.P.Murthy,B.K.Shartria,Y.J.ChoCoincidencePointsan... 相似文献
88.
89.
Using polarised neutrons, the full three-dimensional magnetic structure amplitudes in the Ni1?c Ru c single crystals forc = 0·027, 0·033 and 0·046 were measured. Moment density maps in various portions of the Wigner-Seitz cell were obtained. It is seen from these maps that unlike Ni-based alloys with 3d impurities, the introduction of Ru to the Ni matrix produces extensive perturbations in the diffuse moment density, giving rise to a netpositive diffuse moment which tends to increase with Ru concentration. The asphericity of the host moment at first increases and then decreases with increasing Ru content. Another significant outcome of the present study is the evidence for the reversal of the sign of the Ru moment, from negative to positive, obtained by comparing the shape of the spherical site form factors of the three-alloy concentrations with the Ni spherical form factor itself. The sign reversal of the impurity moment is confirmed by the form factor analyses. Strong local environmental effects seem to play a major role in this alloy system. 相似文献
90.
A polarised neutron study of the ferromagnetic Heusler alloy Cu2Mn0.863Al1.057 has been made. It has been concluded that the magnetic moment density is primarily situated on the Mn ions. On assigning
the Mn-moment value, the observed magnetic form factor is found to be in good agreement with the Mn2+ free ion form factor calculated by Watson and Freeman. A slight asphericity has been observed in the moment density. It is
estimated that there are about 3% excess 3d-electrons in the Eg states compared to spherical distribution. There is evidence of a very small positive polarisation of
the Cu atoms. No appreciable conduction electron polarisation is found. 相似文献