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81.
Alexandru Dimca Fayçal Maaref Claude Sabbah Morihiko Saito 《Mathematische Annalen》2000,318(1):107-125
Using local cohomology and algebraic -Modules, we generalize a comparison theorem between relative de Rham cohomology and Dwork cohomology due to N. Katz, P. Monsky,
A. Adolphson and S. Sperber.
Received June 10, 1999 / Published online July 20, 2000 相似文献
82.
Alexandru Nedelcu Eric Costard Philippe Bois Xavier Marcadet 《Infrared Physics & Technology》2007,50(2-3):227-233
Recent results obtained on building blocks for future third generation infrared focal plane arrays (FPAs) are presented. Our approach concerning the FPA performance assessment and small pixels modelling is exposed. We also demonstrate the ability of the quantum well infrared photodetector technology to answer the needs for compact (20 μm pitch) polarimetric FPAs. Finally, we present our first results on mid-wave infrared detectors at wavelengths below 4.2 μm. 相似文献
83.
In the present paper we want to develop an analytical model to study the thermal behavior of multi-layered solid media in interaction with a laser beam. We suppose that each layer has a constant thermal conductivity. We consider that the laser beam is formed by decoupled [Phys Rev A 1996; 53: 4435] multi-modes Hermite–Gauss beams. The model is applied using the classical heat equation which was solved using the integral transform method [Infrared Phys Technol 2002; 42: 31; Optics Laser Technol 2004; 36: 219–22; Optics Laser Technol 2004; 36: 677–9; Proc SPIE 2003; 5227: 323]. 相似文献
84.
Valentina Uivarosi Mihaela Badea Rodica Olar Dana Marinescu Teodor Octavian Nicolescu George Mihai Nitulescu 《Journal of Thermal Analysis and Calorimetry》2011,105(2):645-650
Three new complexes with ligands belong to the fluoroquinolone class having the general formula [RuL2Cl2]Cl nH2O ((1) L: norfloxacin (nf), n = 4; (2) L: ciprofloxacin (cp), n = 3; (3) L: enrofloxacin (enro), n = 5) were synthesized and characterized by chemical analysis UV–Vis and IR spectroscopy. In all complexes fluoroquinolone
derivative acts as bidentate chelate ligand. The thermal behavior steps were investigated in synthetic air flow. The thermal
transformations are complex processes according to TG and DTG curves including dehydration, quinolone derivative degradation,
as well as RuCl3 conversion in RuO2. 相似文献
85.
We present a simulation study of the coherent transport of electrons through high permittivity (high-κ) dielectric barriers using the non-equilibrium Green’s function (NEGF) formalism. Calculation and useful formula are established for a one-dimensional grid using a finite-difference scheme and an effective-mass depending on the position along the grid. A numerical simulation code is used to investigate the tunneling properties and the transmission coefficient of different metal–insulator–metal structures with stacked dielectrics and to compare single- or two-layer high-κ dielectric stacks in terms of tunneling transmission coefficient and local density-of-states. We particularly highlight the influence of wave-function reflections against barrier discontinuity on the transmission coefficient, especially in two-layer high-κ dielectric stacks. 相似文献
86.
Dumitru Oancea Valentin Munteanu Domnina Razus 《Journal of Thermal Analysis and Calorimetry》2010,102(3):993-1000
The transient response of the input power necessary to maintain isothermal conditions after a step temperature perturbation
applied to a platinum wire immersed in a gaseous fuel/air mixture allows for the measurement of the reaction heat flow rate,
directly related to the rate of the catalytic combustion. The S-shaped variation of this rate in time is employed to evaluate
the induction period of the catalytic ignition. The effect of mixture composition, total pressure, and catalyst temperature
on the induction period for the catalytic ignition of lean to stoichiometric n-pentane/air mixtures on isothermally heated platinum wire is reported and discussed. The mixture composition was varied between
1.40 and 2.56% n-pentane in air, the total pressure between 20 and 101 kPa, and the wire temperature between 470 and 600 K. The reaction rates,
turnover frequencies, overall and partial reaction orders, and activation energies were determined from the analysis of the
obtained results and compared to other reported data. 相似文献
87.
88.
Every compact symmetric bilinear form B on a complex Hilbert space produces, via an antilinear representing operator, a real spectrum consisting of a sequence decreasing to zero. We show that the most natural analog of Courant's minimax principle for B detects only the evenly indexed eigenvalues in this spectrum. We explain this phenomenon, analyze the extremal objects, and apply this general framework to the Friedrichs operator of a planar domain and to Toeplitz operators and their compressions. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
89.
Alexandru V. Asimit 《Insurance: Mathematics and Economics》2008,43(3):407-411
We consider an extension of the classical compound Poisson risk model, where the waiting time between two consecutive claims and the forthcoming claim are no longer independent. Asymptotic tail probabilities of the reinsurance amount under ECOMOR and LCR treaties are obtained. Simulation results are provided in order to illustrate this. 相似文献
90.
Alexandru L. Let David E. Mainwaring Colin Rix Pandiyan Murugaraj 《Journal of Non》2008,354(15-16):1801-1807
Titanium alkoxides react at room temperature with H2S to form an amorphous titanium alkoxy-sulfide precursor which can be converted to TiS2 by heat-treatment in a flowing H2S gas stream. The reaction of titanium isopropoxide (Ti(OPri)4) with H2S in n-butylamine solvent has been studied using infrared spectroscopy (FTIR), gas chromatography/mass spectroscopy (GC/MS), XRD and EDAX measurements. Based on these studies, it is shown that a partially sulfidized alkoxide precursor forms through the partial replacement of some alkoxy groups by hydrosulfide moieties. The alkoxy-hydrosulfide is believed to form following a thiolysis–condensation mechanism similar to the hydrolysis–condensation process that occurs during the oxide sol–gel reaction. The alkoxy-hydrosulfide species then undergoes complete sulfidization at 800 °C in a stream of H2S to yield pure, hexagonal TiS2 in either film or powder forms. 相似文献