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51.
52.
Reasonable estimates of ternary solid-liquid equilibrium can be obtained by application of the Wilson and UNIFAC models. The solubilities of octadecanoic, eicosanoic, docosanoic, and o-toluic acids in binary solvents consisting of a common component (cyclohexane) and a varying second component (heptane, ethanol, methanol, 2-propanol, and 1-butanol) have been measured by a dynamic method from 290 to 340 K. The systems containing cyclohexane-alcohols mixed solvents were found to exhibit a synergistic effect of solubility. The best prediction was obtained for the Wilson equation utilizing temperature dependent ij parameters. For solubilities in nonpolar solvents, the standard deviations for predicted solubilities are comparable to the experimental errors.Presentation to First International Symposium on Solubility Phenomena, University of Western Ontario, London, Ontario, August 21–23, 1984.  相似文献   
53.
Conclusions The complete structure of the repeating unit of a specific polysaccharide chain of an antigenic liposaccharide of bacteriaShigella dysenteriae Type 3, has been established.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1613–1619, July, 1977.  相似文献   
54.
S Bose  PL Knight  MB Plenio  V Vedral 《Pramana》2001,56(2-3):383-391
We present a rare example of a decay mechanism playing a constructive role in quantum information processing. We show how the state of an atom trapped in a cavity can be teleported to a second atom trapped in a distant cavity by the joint detection of photon leakage from the cavities. The scheme, which is probabilistic, requires only a single three level atom in a cavity. We also show how this scheme can be modified to a teleportation with insurance.  相似文献   
55.
A dynamic column breakthrough (DCB) apparatus was used to study the separation of CH4+N2 gas mixtures using two zeolites, H+-mordenite and 13X, at temperatures of (229.2 and 301.9)?K and pressures to 792.9?kPa. The apparatus is not limited to the study of dilute adsorbates within inert carrier gases because the instrumentation allows the effluent flow rate to be measured accurately: a method for correcting apparent effluent mass flow readings for large changes in effluent composition is described. The mathematical framework used to determine equilibrium adsorption capacities from the dynamic adsorption experiments is presented and includes a method for estimating quantitatively the uncertainties of the measured capacities. Dynamic adsorption experiments were conducted with pure CH4, pure N2 and equimolar CH4+N2 mixtures, and the results were compared with similar static adsorption experiments reported in the literature. The 13X zeolite had the greater adsorption capacity for both CH4 and N2. At 792?kPa the equilibrium capacities of the 13X zeolite increased from 2.13±0.14?mmol?g?1 for CH4 and 1.36±0.10?mmol?g?1 for N2 at 301.9?K to 3.97±0.19?mmol?g?1 for CH4 and 3.33±0.12?mmol?g?1 for N2 at 229.2?K. Both zeolites preferentially adsorbed CH4; however, the mordenite had a greater equilibrium selectivity of 3.5±0.4 at 301.9?K. Equilibrium selectivities inferred from pure fluid capacities using the Ideal Adsorbed Solution theory were limited by the accuracy of the literature pure fluid Toth models. Equilibrium capacities with quantitative uncertainties derived directly from DCB measurements without reference to a dynamic model should help increase the accuracy of mass transfer parameters extracted by the regression of such models to time dependent data.  相似文献   
56.
The main objective of this research was to investigate to what extent the potential C dynamics of soil organic matter (SOM) are related to the degree of 13C enrichment with increasing depth in soil profiles under permanent grassland. The evolution of the C content and the 13C natural abundance (delta13C value) of SOM were investigated in three soil profiles (0-40 cm depth) under permanent grassland of varying texture (a loamy sand, a loam and a clay loam soil). The delta13C value of the SOM showed a gradual increase with increasing depth and decreasing C content in the profiles, ranging from 1.9 per thousand (loamy sand soil), 2.9 per thousand (clay loam soil) and 4 per thousand (loam soil) in relation to the delta13C value of SOM at the surface. The relationship between the 13C enrichment and total organic C content at different depths in the profiles (down to 40 cm depth in the loam and clay loam soil, down to 25 cm depth in the loamy sand soil) could be well described by the Rayleigh equation. The enrichment factors epsilon, associated with the Rayleigh approximation of the data, ranged from -1.57 per thousand (clay loam soil) to -1.64 per thousand (loamy sand soil) and -1.91 per thousand (loam soil). The potential C dynamics in four depth intervals from the profiles (0-10, 10-20, 20-30 and 30-40 cm depth) were determined by means of an incubation experiment. The C decomposition rate constants from the four sampling depths in the profiles showed a significant, positive correlation (y = 0.21x + 0.018, R(2) = 0.66, p < 0.005) with the corresponding Deltadelta13C values (change of the delta13C value per depth increment). A better correlation was obtained when only the data from the upper 20 cm in the profiles (y = 0.21x + 0.019, R(2) = 0.78, p < 0.05) were considered. These results suggest that the Deltadelta13C values in the surface layers of profiles under permanent grassland may serve as an indicator of the potential degradability or the stability of the SOM (in terms of C decomposition rate constants).  相似文献   
57.
We study bulk-boundary correlators in topological open membranes. The basic example is the open membrane with a WZ coupling to a 3-form. We view the bulk interaction as a deformation of the boundary string theory. This boundary string has the structure of a homotopy Lie algebra, which can be viewed as a closed string field theory. We calculate the leading order perturbative expansion of this structure. For the 3-form field we find that the C-field induces a trilinear bracket, deforming the Lie algebra structure. This paper is the first step towards a formal universal quantization of general quasi-Lie bialgebroids.Dept. of Particle Physics, Weizmann Institute, Rehovot, IsraelMathematics Graduate Center, CUNY, New York, USA  相似文献   
58.
59.
The results of sputtering coefficient measurements for pure metals, alloys, amorphous alloys, semiconductors, and highly oriented pyrolytic graphite under irradiation by high energy ions are considered. The possible mechanisms of strong sputtering of materials with high defect concentrations are discussed. The three-dimensional thermal spike model (“hot ion track”) with the temperature dependence of thermodynamic parameters (specific heat thermal conductivity) is formulated for single-layer mono-and polycrystals and multilayer systems (materials). The results of a numerical solution to the introduced system of partial differential equations are considered for the lattice and electronic subsystem temperatures around and along the fast heavy ion trajectory as a function of the time t, as well as radial r and longitudinal z coordinates, taking into account possible phase transitions such as melting and evaporation. The results obtained are discussed.  相似文献   
60.
We have measured the ratios of antiparticles to particles for charged pions, kaons, and protons near mid-rapidity in central Au+Au collisions at sqrt[s(NN)] = 130 GeV. We observe / = 1.00+/-0.01(stat)+/-0.02(syst), / = 0.91+/-0.07(stat)+/-0.06(syst), and

/

= 0.60+/-0.04(stat)+/-0.06(syst). The / and

/

ratios give a consistent estimate of the baryo-chemical potential mu(B) of 45 MeV, a factor of 5-6 smaller than in central Pb+Pb collisions at sqrt[s(NN)] = 17.2 GeV.  相似文献   

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