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531.
Point of attraction theory is an important tool to analyze the local convergence of iterative methods for solving systems
of nonlinear equations. In this work, we prove a generalized form of Ortega-Rheinbolt result based on point of attraction
theory. The new result guarantees that the solution of the nonlinear system is a point of attraction of iterative scheme,
especially multipoint iterations. We then apply it to study the attraction theorem of the Frontini-Sormani family of multipoint
third order methods from Quadrature Rule. Error estimates are given and compared with existing ones. We also obtain the radius
of convergence of the special members of the family. Two numerical examples are provided to illustrate the theory. Further,
a spectral analysis of the Discrete Fourier Transform of the numerical errors is conducted in order to find the best method
of the family. The convergence and the spectral analysis of a multistep version of one of the special member of the family
are studied. 相似文献
532.
Complexes of the formula (N2H5)2M(C2O4)2·nH2O where M = Co, Ni, Cu and n = 3, 2, 1 respectively have been prepared and their spectral, magnetic and thermal properties investigated. The copper complex, (N2H5)2Cu(C2O4)2·H2O has a square planar geometry with no coordination of hydrazinium cations as confirmed by a single crystal X-ray study. Nickel and cobalt form octahedral complexes and X-ray powder patterns reveal that the complexes are not isomorphous. 相似文献
533.
Let G be a group of automorphisms of a function field F of genus gF over an algebraically closed field K. The space of holomorphic differentials of F is a gF? dimensional K-space. In response to a query of Hecke, Chevalley and Weil (Abh. Math. Sem. Univ. Hamburg, 10 (1934), 358–361) completely determined the structure of as representation space for G in the classical case. They carried out the proof for the special case in which F is unramified over the fixed field of G. The case of cyclic ramified extensions had been previously considered by Hurwitz (Math. Ann., 41 (1893), 37–45). Weil (Abh. Math. Sem. Univ. Hamburg, 11 (1935), 110–115) gave a proof in the general case. The treatment in the last two papers is analytical. In characteristic p, the problem is open. If G is cyclic and F is unramified over the fixed field E of G, Tamagawa (Proc. Japan Acad., 27 (1951), 548–551) proved that the representation is the direct sum of one identity representation of degree 1 and gE ? 1 regular representations. The principal object of this paper is an extension of Tamagawa's result to arbitrary cyclic extensions of p-power degree. The number of times an indecomposable representation of given degree occurs in the representation of G on is explicitly determined in terms of gE and the Witt vector characterizing the extension . The paper also contains a purely algebraic proof of the result of Chevalley and Weil for arbitrary cyclic extensions of degree relatively prime to p. Using character theory, it can be extended to arbitrary groups of order relatively prime to the characteristic. 相似文献
534.
Multimillion Atom Molecular Dynamics Simulations of Nanostructures on Parallel Computers 总被引:2,自引:0,他引:2
Vashishta Priya Kalia Rajiv K. Nakano Aiichiro 《Journal of nanoparticle research》2003,5(1-2):119-135
Scalable space–time multiresolution algorithms implemented on massively parallel computers enable large-scale molecular dynamics (MD) simulations involving up to a billion atoms. Multimillion atom MD simulations are performed to study critical issues in the area of structural and dynamical correlations in nanostructures. Our simulation research is focused on a few semiconductor, ceramic, and metallic nanostructures. These nanostructures systems include: nanometer-scale stress patterns in silicon/silicon nitride nanopixels; self-limiting growth and critical lateral sizes in gallium arsenide/indium arsenide nanomesas; structural transformation in colloidal semiconductor nanocrystals; nanoindentation of crystalline and amorphous silicon nitride films; and dynamics of oxidation of metallic aluminum nanoparticles. 相似文献
535.
Levine and Steinhardt's expression is generalised for the structure factor of a binary quasicrystal with AτB composition. The atomic model used in this generalisation is based on the embedding of quasiperiodic chains of A and B atoms such that there is a B atom within every long interval of the A-chain. For the proposed embedding scheme, the range of interpenetration length as well as the ratio of long and short intervals in the two chains are shown to affect the diffracted intensities drastically. The effect of order-disorder on the motif, average quasilattice constant and diffracted intensities is also considered. Conditions for the composite chain to become self-similar, which for the most general embedding is not necessary, are obtained. The application of present decoration scheme to vacancy ordered phases is discussed. 相似文献
536.
An efficient and mild method for transesterification of β-ketoester catalyzed by Mo-Z1O2 solid acid catalyst is described. 相似文献
537.
538.
A new technique has been developed to measure isotope shifts of high-lying atomic levels using multi-step photoionization.
This technique has been demonstrated with the measurement of isotope shift between235U and238U isotopes in the energy level at 34372.992 cm−1. The value of isotope shift thus measured matches well with the value reported in literature. 相似文献
539.
Capillary forces between surfaces with nanoscale roughness 总被引:4,自引:0,他引:4
Rabinovich YI Adler JJ Esayanur MS Ata A Singh RK Moudgil BM 《Advances in colloid and interface science》2002,96(1-3):213-230
The flow and adhesion behavior of fine powders (approx. less than 10 microm) is significantly affected by the magnitude of attractive interparticle forces. Hence, the relative humidity and magnitude of capillary forces are critical parameters in the processing of these materials. In this investigation, approximate theoretical formulae are developed to predict the magnitude and onset of capillary adhesion between a smooth adhering particle and a surface with roughness on the nanometer scale. Experimental adhesion values between a variety of surfaces are measured via atomic force microscopy and are found to validate theoretical predictions. 相似文献
540.
A one-step, room-temperature method is described to chemically synthesize bulk quantities of microns long, 100-180 nm diameter nanofibers of electrically conducting poly(3,4-ethylenedioxythiophene)(PEDOT) in the form of powders, or as optically transparent, substrate-supported films using a V2O5 seeding approach. 相似文献