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1.
In the present paper, we deal with the complex Szász-Durrmeyer operators and study Voronovskaja type results with quantitative estimates for these operators attached to analytic functions of exponential growth on compact disks. Also, the exact order of approximation is found. 相似文献
2.
A. K. SINHA S. P. MATHUR ASHOK K. SINHA Y. N. MISHRA K. K GUPTA 《International Journal of Electronics》2013,100(5):937-944
Based on the solution of the Riccati equation, a hyperbolically tapered microstrip transmission line for matching a complex load to a standard coaxial cable is designed. An iterative procedure is used to yield the phase constant leading to an accurate design. A numerical example is considered. The result shows that a tremendous reduction in the size of matching components can be achieved if hyperbolic instead of uniform transmission lines are used. This is highly advantageous in the miniaturization of solid state circuits. 相似文献
3.
SOURENDU GUPTA 《Pramana》2011,76(5):801-809
This talk discusses methods of extending lattice computations at finite temperature into regions of finite chemical potential,
and the conditions under which such results from the lattice may be compared to experiments. Such comparisons away from a
critical point are absolutely essential for quantitative use of lattice QCD in heavy-ion physics. An outline of various arguments
which can then be used to locate the critical point is also presented. 相似文献
4.
To test a developed reconstruction algorithm for cone beam geometry, whether it is transmission or emission tomography, one
needs projection data. Generally, mathematical phantoms are generated in three dimensions and the projection for all rotation
angles is calculated. For non-symmetric objects, the process is cumbersome and computation intensive. This paper describes
a simple methodology for the generation of projection data for cone beam geometry for both transmission and emission tomographies
by knowing the object’s attenuation and/or source spatial distribution details as input. The object details such as internal
geometrical distribution are nowhere involved in the projection data calculation. This simple approach uses the pixilated
object matrix values in terms of the matrix indices and spatial geometrical coordinates. The projection data of some typical
phantoms (generated using this approach) are reconstructed using standard FDK algorithm and Novikov’s inversion formula. Correlation
between the original and reconstructed images has been calculated to compare the image quality. 相似文献
5.
In the present paper, we deal with the complex Szasz-Durrmeyer operators and study Voronovskaja type results with quantitative estimates for these operators attached to analytic functions of exponential growth on compact disks. Also, the exact order of approximation is found. 相似文献
6.
The kinetics and mechanism of ligand substitution reactions of nitrilotriacetatoiron(Ⅲ), [Fe(NTA)], and N-(2-hydroxyethyl)-ethylenediaminetfiacetatoiron(Ⅲ), [Fe(HEDTA)], complexes with 4-(2-pyridylazo) resorcinol (Par) has been investigated at pH = 9.0±0.02, I= 0.1mol·1~(-1) (NaClO_4), and temp. = 25 ±0.1℃ and 30±0.1℃ respectively. The reaction has been studied spectrophotometrically at 496 nm. (λ_(max) of Fe(Par)_2). In both reactions the final product was [Fe(Par)_2]~-. The values of second order rate constants for NTA and HEDTA exchange reactions are (10.0±0.8)×10~1·mol~(-1)·s~(-1) and (2.7± 0.1)×10~(-1) 1·mol~(-1)·s~(-1) respectively. The reactions of NTA and HEDTA exchange were studied in the pH range 6-9.5 and 7-10.85 respectively. The rate of reacton of [Fe(NTA)] with HPar~- first increases with pH and then levels off. However, in the case of [Fe(HEDTA)] reaction, the rate increases monotonically with increase of pH in the specified range. The reverse reactions between [Fe(Par)_2 相似文献
7.
Although the problem of scheduling dynamic job shops is well studied, setup and changeover times are often assumed to be negligibly small and therefore ignored. In cases where the product mix changes occur frequently, setup and changeover times are of critical importance. This paper applies some known results from the study of multi-class single-server queues with setup and changeover times to develop an approximation for evaluating the performance of job shops. It is found that the product mix, setup and changeover times, and scheduling rules affect the performance significantly, in particular at high levels of machine utilisation. This approach could be used to determine the required level of flexibility of machines and to choose an appropriate scheduling policy such that production rates remain within acceptable limits for foreseeable changes in the product mix. 相似文献
8.
In a plethora of microfabrication processes available now-a-days, one needs to choose the best possible option suitable for the job on-hand. This paper discusses three versatile approaches to fabricate microchips for lab-on-chip (LOC) applications in general and uranium analysis in water samples as a specific case. Laser-direct patterning succeeded by soft lithography, laser micropatterning followed by HF etching and micromilling have been demonstrated which not only suit the objective of uranium detection but also for most of the LOC applications. The different techniques elaborated enable development of LOCs in polymers as well as glass with a depth ranging from few microns to 100 μm or higher while squeezing the reaction lengths of ~10 cm on a 20 mm × 32 mm chip. This development equips one to design and develop more complicated LOC devices to take advantage of their hastened reaction cycle with minimal waste in terms of capital and maintenance cost. 相似文献
9.
Despite spectacular advances in fixing the neutrino mass and mixing parameters through various neutrino oscillation experiments, we still have little knowledge about the magnitudes of some vital parameters in the neutrino sector such as the absolute neutrino mass scale, effective Majorana mass mee measured in neutrinoless double beta decay. In this context, the present work aims to make an attempt to obtain some bounds for mee and the lightest neutrino mass using fairly general lepton mass matrices in the Standard Model. 相似文献
10.
GUPTA R. K SINGH K 《偏微分方程(英文版)》2009,22(2):97-110
The Lie-group formalism is applied to investigate the symmetries of the modified Boussinesq system with variable coefficients. We derived the infinitesimals and the admissible forms of the coefficients that admit the classical symmetry group. The reduced systems of ordinary differential equations deduced from the optimal system of subalgebras are further studied and some exact solutions are obtained. 相似文献