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61.
This paper addresses a license plate localization (LPL) algorithm for a complex background. Most of LPL algorithm works on restricted conditions, as well as on a principle of sequential elimination of blocks from image level to final LP candidate region. In most of algorithms, blocks are filtered out for not satisfying required LP features in a top-down approach and this may result in a poor efficiency in a complex scenario. The major steps of the proposed approach are adaptive edge mapping, saliency measure of edge based rules with confidence level estimation using fuzzy rules and final step for reassessment of decision by colour attributes filtering. The proposed algorithm is adaptive to across the country variations in LP standards, as well as it is tested on two data sets each one consisting of more than 700 images, set-1 being for good images while set-2 including only constrained images. The algorithm is tested for a low contrast due to overexposure or poor lighting, existence of multiple plates, variation in aspect ratio and compatible background conditions. It has been observed, that the performance degradation imposing complex condition is nominal.  相似文献   
62.
Structural and superconducting properties of yttrium substituted Ce1-xYx(O/F)FeAs superconductors have been investigated for the first time. All the compounds crystallize in the tetragonal ZrCuSiAs structure type. There is a decrease in both the a and c lattice parameters on increasing yttrium substitution (with fixed F content) along with a substantial enhancement of the superconducting transition temperature (Tc) and upper critical field (Hc2) indicating the influence of chemical pressure. Interestingly the maximum Tc (~48 K) was observed for an intermediate composition (Ce0.5Y0.5O0.9F0.1FeAs) which is higher than either of the parent Y or Ce-compounds, (YO0.9F0.1FeAs (~10 K) and Ce(O/F)FeAs (~42 K)). The transition temperature was also found to be nearly independent of the electron -doping introduced by fluoride substitution (0.1 to 0.2 moles per formula unit) indicating the significance of the charge reservoir layer (Ce-O). The yttrium substituted (fluoride free) compositions of the type, Ce1-xYxOFeAs were found to be semimetallic like the parent compound CeOFeAs with the shift in the anomaly temperature towards low temperature on substitution of yttrium ions. Hall coefficient and thermopower measurements show an increase in charge carriers (electrons) through Y-doping in fluorine doped CeOFeAs.  相似文献   
63.
Copolymerization reactivity ratios of the systems 4-vinyl-pyridine (VP)-methacrylic acid (MA), dimethylamino methacrylate (DMAM)-MA, and VP-DMAM were obtained using the Fineman-Ross procedure. The experimental values were found to differ considerably from the values calculated from the Q-e scheme. R1 and r2 values calculated using seven different models for the VP-MA system have been compared with the experimental values.  相似文献   
64.
The kinetics of the mechanism of the polymerization of methyl methacrylate initiated by the glycerol/Mn(III) acetate redox system has been investigated in aqueous sulfuric acid medium in the temperature range of 40 to 50 °C. The effects of glycerol, methyl methacrylate, metal ion, acetic acid, and sulfuric acid on the rates of polymerization have been studied. One striking observation is that the increase in monomer concentration steadily decreases the rate of polymerization, contrary to what was observed in the case of acrylonitrile. On the basis of these observations, an appropriate kinetic scheme and rate expression have been developed.  相似文献   
65.
The present communication discusses the kinetics of the retarding effect of phenol on the polymerization of acrylonitrile initiated by azobisisobutyronitrile (AIBN). The results are treated on the basis of the scheme proposed by Tüdös et al.  相似文献   
66.
67.
Substituent effects in the reactivities of phenols towards polyacrylonitrile radicals have been studied in terms of Swain and Luptons' field (Fk) and resonance (Rk) components of the substituent parameters and the unique positional weighting factors (fj and rj) proposed by Williams and Norrington, with the aid of the following equation:
Pi = xi?iFk + ßirjKi + ei + Pio
Pi′s are the rate parameters, Pi0 being that for a standard reference compound. Two types of rate parameters have been employed—one, suggested by Simonyi, Tüdös and Pospisil (β) and another, suggested by us, (K), which is obtained from a plot of [Monomer]/(rate of polymerisation) vs [Phenol]. The correlations have been found to be quite satisfactory with both β and K. An attempt has been made to ascertain the nature of the transition state from the reaction parameters αi and βi; a dipolar transition state is suggested. The anomalous kinetic behaviour of hydroxy phenols has been discussed.  相似文献   
68.
69.
Summary In recombinant fermentations the plasmid loss probability per generation depends on the specific growth rate, which is related linearly to the dilution rate. A model with this feature and incomplete mixing has been studied analytically for stationary state behavior. While the kinetic parameters place upper limits on the dilution rate for a feasible stationary state in a well-mixed bioreactor, the feasible and nonfeasible regions for an incompletely mixed reactor are separated by either a straight line or a plane, whose position is determined by the mixing conditions.</o:p>  相似文献   
70.
Consequent to our recent papers on C(60) colloidal aggregates in CS(2) solution (Bokare, A. D.; Patnaik, A. J. Phys. Chem. 2003, 107, 6079-6086) and their probable electron density distribution (Bokare, A. D.; Patnaik, A. J. Chem. Phys. 2003, 119, 4529-4538), the solution-phase structure of C(60) in nonpolar o-xylene is reported using a positronium (Ps) atom as a fundamental probe, mapping changes in the local electron density of the microenvironment. Spontaneous formation of stable aggregates in the colloidal range (approximately 90-150 nm) was observed in a concentration range of 0.14-0.36 g/dm(3), beyond which they broke. An onset concentration for aggregate formation at 0.14 g/dm(3), as against 0.06 g/dm(3) for the polar CS(2) solvent, was noted and was substantiated by complete quenching of pyrene fluorescence at and beyond this onset due to photoinduced electron transfer from the pyrene excited state to the C(60) aggregate. An order-disorder phase transition led to a notable geometry change of the colloidal particles; a sphere-to-nonuniform cylinder transition following an increase in the C(60) concentration from 0.14 to 0.36 g/dm(3) revealed the aggregate curvature/internal modes to have been influenced by energetic/entropic and/or hydrodynamic interactions in the solvent medium. Transmission electron microscopy images of the aggregated clusters, in corroboration with Ps annihilation characteristics and pyrene fluorescence, revealed the clusters to be hexagonally close packed microcrystals.  相似文献   
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