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101.
J. A. Muller C. Reinhardt C. Fischbach A. Siebenschub V. Stanek N. M. Randall K. Bogoluboff H. Wdowiszewski F. Garrat D. J. Demorest J. R. Cain H. E. Walters F. C. T. Daniels A. J. Field A. Terni P. Malaguti B. S. Evans L. W. Winkler O. L. Barnebey G. L. Kelley J. A. Wiley E. Little J. Costa M. Gröger H. O. Ward P. Slawik W. Hild und F. Simion 《Fresenius' Journal of Analytical Chemistry》1923,63(9):348-359
Ohne Zusammenfassung 相似文献
102.
D. Chandra M. W. Goodwin M. C. Chen J. A. Dodge 《Journal of Electronic Materials》1993,22(8):1033-1037
Arsenic diffusion coefficients were measured in HgCdTe at 350°C within the single phase field. The diffusion coefficients
displayed a strong dependence on Hg pressure, increasing by more than 1×103 with decreasing Hg pressure. These measurements were performed by growing As doped HgCdTe films by Hg-rich liquid phase epitaxy
on undoped or In-doped base layers, where the growth temperature ranged between 330 and 350°C. Use of these low growth temperatures
under Hg-rich conditions permitted attainment of virtual step profiles in As, with negligible diffusion into the base layers.
These provided ideal starting points for subsequent diffusion anneals. Diffusion of arsenic under selected low Hg pressures
was then employed to tune the positioning of the p/n junction for double layer heterojunction films, by locating it ahead
of the heterointerface. Formation of valence band barriers to the photogenerated minority carriers across the junction could
thus be avoided. When on the other hand, diffusion experiments were performed under Hg saturated conditions, the heterointerface
moved at a faster rate than the p/n junction, leading to the formation of valence band barriers. 相似文献
103.
Stuart S. Antman Randall S. Mariow 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》1992,43(1):7-27
Summary This paper treats new effects, such as transcritical bifurcation and extinction, exhibited by the solution branches of buckled states of nonlinearly elastic columns. The general models used are intimately related to the three-dimensional theory of nonlinear elasticity. These new effects are caused by the interaction of the nonlinearity of material response, the lack of symmetry in the cross-section, the nature of boundary conditions, and the nonuniformity of the rod. Although a variety of sophisticated analytic tools are used to treat local and global branching of solutions, the main emphasis is placed on the mechanics that underlies the form of the governing equations.Dedicated to Prof. Klaus Kirchgässner on the occasion of his sixtieth birthday 相似文献
104.
105.
Bounded knapsack sharing 总被引:1,自引:0,他引:1
J. Randall Brown 《Mathematical Programming》1994,67(1-3):343-382
A bounded knapsack sharing problem is a maximin or minimax mathematical programming problem with one or more linear inequality constraints, an objective function composed of single variable continuous functions called tradeoff functions, and lower and upper bounds on the variables. A single constraint problem which can have negative or positive constraint coefficients and any type of continuous tradeoff functions (including multi-modal, multiple-valued and staircase functions) is considered first. Limiting conditions where the optimal value of a variable may be plus or minus infinity are explicitly considered. A preprocessor procedure to transform any single constraint problem to a finite form problem (an optimal feasible solution exists with finite variable values) is developed. Optimality conditions and three algorithms are then developed for the finite form problem. For piecewise linear tradeoff functions, the preprocessor and algorithms are polynomially bounded. The preprocessor is then modified to handle bounded knapsack sharing problems with multiple constraints. An optimality condition and algorithm is developed for the multiple constraint finite form problem. For multiple constraints, the time needed for the multiple constraint finite form algorithm is the time needed to solve a single constraint finite form problem multiplied by the number of constraints. Some multiple constraint problems cannot be transformed to multiple constraint finite form problems. 相似文献
106.
We consider algebras with one binary operation · and one generator (monogenic) and satisfying the left distributive lawa·(b·c)=(a·b)·(a·c). One can define a sequence of finite left-distributive algebrasAn, and then take a limit to get an infinite monogenic left-distributive algebraA∞. Results of Laver and Steel assuming a strong large cardinal axiom imply thatA∞is free; it is open whether the freeness ofA∞can be proved without the large cardinal assumption, or even in Peano arithmetic. The main result of this paper is the equivalence of this problem with the existence of a certain algebra of increasing functions on natural numbers, called anembedding algebra. Using this and results of the first author, we conclude that the freeness ofA∞is unprovable in primitive recursive arithmetic. 相似文献
107.
The application of optoelectronic technologies and data transmission techniques, developed initially for the telecommunications market, to electronic processor systems offers to overcome interconnect limitations facing designers of these high performance systems. Optical interconnects offer increased data rates, low power consumption, compact size and inherent freedom from the effects of mutual coupling, line capacitance, EMI and topological constraints. This paper describes our investigation of two of the key technologies required for the practical implementation of optical interconnections, namely optoelectronic interface components (the optical bond pads), and the associated hybrid alignment techniques used in their assembly. 相似文献
108.
Finneran JJ Schlundt CE Branstetter B Dear RL 《The Journal of the Acoustical Society of America》2007,122(2):1249-1264
Hearing sensitivity was measured in a bottlenose dolphin before and after exposure to an intense 20-kHz fatiguing tone in three different experiments. In each experiment, hearing was characterized using both the auditory steady-state response (ASSR) and behavioral methods. In experiments 1 and 2, ASSR stimuli consisted of seven frequency-modulated tones, each with a unique carrier and modulation frequency. The tones were simultaneously presented to the subject and the ASSR at each modulation rate measured to determine the effects of the sound exposure at the corresponding carrier frequency. In experiment 3 behavioral thresholds and ASSR input-output functions were measured at a single frequency before and after three exposures. Hearing loss was frequency-dependent, with the largest temporary threshold shifts occurring (in order) at 30, 40, and 20 kHz. ASSR threshold shifts reached 40-45 dB and were always larger than behavioral shifts (19-33 dB). The ASSR input-output functions were represented as the sum of two processes: a low threshold, saturating process and a higher threshold, linear process, that react and recover to fatigue at different rates. The loss of the near-threshold saturating process after exposure may explain the discrepancies between the ASSR and behavioral threshold shifts. 相似文献
109.
Graham?WigleyEmail author Martin?Goodwin Graham?Pitcher Damien?Blondel 《Experiments in fluids》2004,36(4):565-574
This paper describes a combined LDA, PDA and imaging analysis of the pressure swirl spray in the near-nozzle region of a GDI injector. This innovative approach in the use of multiple, complementary diagnostics facilitates the interpretation of a complex spray flow field.The LDA and PDA data were ensemble-averaged into time bins to produce comprehensive time-history and spatial profiles of liquid velocity, droplet velocity and size and the sample number. They indicated times at which the spray exhibited seven different characteristics. These were identified as: (a) pre-swirl spray, (b) spray cone develops, (c) spray cone relaxes, (d) maximum velocity in spray cone, (e) fully developed steady state, (f) spray cone collapses and (g) the spray detaches from the nozzle. The most effective method to present the spatial and temporal development of the spray was to superimpose the velocity vector and drop size field plots onto the spray images.This article is part of the special issue 11th International Symposium on Applications of Laser Techniques to Fluid Mechanics, Lisboa, Portugal, July 2002, January 2004, Vol. 36, Issue no. 1 相似文献
110.
Xiong S Molecke R Bosch M Schunk PR Brinker CJ 《Journal of the American Chemical Society》2011,133(30):11410-11413
Transformation of 2D Au nanoparticle (NP) arrays into large scale, ordered, and oriented nanorod/nanowire arrays supported on a transferrable polymer film has been accomplished. E-beam irradiation followed by room temperature aging of a suspended Au NP/polymethylmethacrylate (PMMA) polymer close packed monolayer results in one-dimensional nanoparticle aggregation, reorientation, and sintering into a high density array of oriented Au nanowires with coherent single-crystal-like interfaces. Molecular dynamics simulations of alkane-thiol capped Au NPs, interacting through the Vincent potential and undergoing 2D Poisson compression, account semiquantitatively for the qualitative features of the transformation. This fabrication approach should be extendable to directing 1D aggregation of highly anisotropic nanostructures in arbitrary NP systems. 相似文献