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81.
82.
Seki S. Yokoyama K. Sotirelis P. 《IEEE journal of selected topics in quantum electronics》1995,1(2):264-274
By taking into account the electrostatic deformation in the band profiles and the temperature dependence of the optical dephasing time, we study the temperature sensitivity of the differential gain, threshold carrier density, and radiative current density in 1.3-μm InP-based strained-layer quantum-well (QW) lasers. Electrostatic deformation is analyzed by the self-consistent numerical calculation of Poisson's equation, the scalar effective-mass equation for the conduction band, and the multiband effective-mass equation for the valence band. The optical dephasing time is then obtained from the intrasubband scattering rates for electrons and holes within the fully dynamic random phase approximation including carrier-carrier and carrier-phonon interactions on an equal basis. It is clarified that the electrostatic band-profile deformation is one of the dominant mechanisms For determining the temperature sensitivity Of the differential gain, while the optical dephasing time has a pronounced influence on the transparent condition at elevated temperatures. We demonstrate that the electrostatic band-profile deformation and the temperature-dependent optical dephasing play essential roles in determining the high-temperature characteristics of InP-based QW lasers 相似文献
83.
Shimizu Y Tamura T Ono M Kasai O Nakajima T 《Drug development and industrial pharmacy》2002,28(8):931-937
We proposed a method for objectively selecting the most fitted rate equation among candidate rate equations based on chemical kinetics by both nonlinear regression analysis and Akaike's information criterion (AIC), to express the decrease of pharmaceutical ingredient as an appropriate equation. Pseudo-zero, first, and second-order rate equations were prepared as candidates beforehand, and AIC was introduced for selecting the most fitted rate equation among the candidates. We compared the proposed method to the Weibull method that expressed any decrease patterns as a single equation.
We quantified the contents of thiamine nitrate (VB1) and taurine after storage for one, three, and six months under 40°C-75% relative humidity by high-pressure liquid chromatography. Decrease patterns of each sample were most fitted to one of the candidate rate equations, that is, pseudo-zero, first, and second-order rate equations, respectively, and the degree of fit in the most fitted equation was superior to that of the Weibull method, except for the pseudo-first-order rate equation.
Moreover, we confirmed that the proposed method was considerably precise for estimating the stability of pharmaceuticals by comparing estimated residual rates and confidence intervals to experimental data. 相似文献
We quantified the contents of thiamine nitrate (VB1) and taurine after storage for one, three, and six months under 40°C-75% relative humidity by high-pressure liquid chromatography. Decrease patterns of each sample were most fitted to one of the candidate rate equations, that is, pseudo-zero, first, and second-order rate equations, respectively, and the degree of fit in the most fitted equation was superior to that of the Weibull method, except for the pseudo-first-order rate equation.
Moreover, we confirmed that the proposed method was considerably precise for estimating the stability of pharmaceuticals by comparing estimated residual rates and confidence intervals to experimental data. 相似文献
84.
Keisuke Omae In-Tae Bae Muneyuki Naito Manabu Ishimaru Yoshihiko Hirotsu James A. Valdez Kurt E. Sickafus 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2006,250(1-2):300-302
We have performed high-dose Fe ion implantation into Si and characterized ion-beam-induced microstructures as well as annealing-induced ones using transmission electron microscopy (TEM) and grazing-incidence X-ray diffraction (GIXRD). Single crystals of Si(1 0 0) substrate were irradiated at 623 K with 120 keV Fe+ ions to a fluence of 4 × 1017 cm−2. The irradiated samples were then annealed in a vacuum furnace at temperatures ranging from 773 K to 1073 K. Cross-sectional TEM observations and GIXRD measurements revealed that a layered structure is formed in the as-implanted specimen with ε-FeSi, β-FeSi2 and damaged Si, as component layers. A continuous β-FeSi2 layer was formed on the topmost layer of the Si substrate after thermal annealing. 相似文献
85.
In-Tae Bae Manabu Ishimaru Yoshihiko Hirotsu 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2006,250(1-2):315-319
Electron-beam-irradiation effects on silicon carbide (SiC) was investigated as a function of the irradiated temperatures. Single crystalline 6H-SiC was irradiated with 300 kV electrons at temperatures ranging from −170 to 250 °C. It was found that amorphous SiC is induced at −170 °C and room temperature, while crystalline Si is formed at 250 °C with a high electron fluence. It is considered that preferential knock-on displacement of C atoms and damage recovery play an important role in the formation of the amorphous SiC and crystalline Si. 相似文献
86.
Hirofumi Hirayama Toshihiro Itoh Yoshihiko Nakaki Takahiko Yoshida 《Artificial Life and Robotics》2005,9(3):144-160
A mathematical method is introduced to characterize the electrokinetic behavior (electrophoresis) of a biomolecular particle which passes through a specific channel pore on an excitable biological membrane. The basic approach was first proposed by Booth (1950). The system was described by an equation of continuity and an equation of motion in which the driving force involves the diffusion effect, the hydrostatic pressure, and the electrostatic potential. By assuming linear relations between the velocity and the applied electrical field, solutions for the potential, pressure, and velocity were given by a series expansion of the charges on the particle. To examine the influence of ions surrounding the particle and forming an ionic cloud, the Debye–Huckel parameter was introduced. As the thickness of the double layer around the particle increased, the potential, velocity, pressure, and viscosity were changed significantly. The maximum influence was obtained when the radius of the particle became equal to the thickness of the double layer. Although this theory is valid for a charged, spherical, nonconducting particle only, the method is available for evaluating the kinetic behavior of a biomolecule that passes through a channel pore on a cellular membrane.This work was presented, in part, at the 8th International Symposium on Artificial Life and Robotics, Oita, Japan, January 24–26, 2003 相似文献
87.
We propose an axiomatization of fixpoint operators in typed call-by-value programming languages, and give its justifications in two ways. First, it is shown to be sound and complete for the notion of uniform T-fixpoint operators of Simpson and Plotkin. Second, the axioms precisely account for Filinski's fixpoint operator derived from an iterator (infinite loop constructor) in the presence of first-class continuations, provided that we define the uniformity principle on such an iterator via a notion of effect-freeness (centrality). We then explain how these two results are related in terms of the underlying categorical structures. 相似文献
88.
Generalized Partial Computation (GPC) is a program transformation method utilizing partial information about input data, abstract
data types of auxiliary functions and the logical structure of a source program. GPC uses both an inference engine such as
a theorem prover and a classical partial evaluator to optimize programs. Therefore, GPC is more powerful than classical partial
evaluators but harder to implement and control. We have implemented an experimental GPC system called WSDFU (Waseda Simplify-Distribute-Fold-Unfold).
This paper demonstrates the power of the program transformation system as well as its theorem prover and discusses some future
works.
Yoshihiko Futamura, Ph.D.: He is Professor of Department of Information and Computer Science and the director of the Institute for Software Production
Technology (ISPT) of Waseda University. He received his BS in mathematics from Hokkaido University in 1965, MS in applied
mathematics from Harvard University in 1972 and Ph.D. degree from Hokkaido University in 1985. He joined Hitachi Central Research
Laboratory in 1965 and moved to Waseda University in 1991. He was a visiting professor of Uppsala University from 1985 to
1986 and a visiting scholar of Harvard University from 1988 to 1989. Automatic generation of computer programs and programming
methodology are his main research fields. He is the inventor of the Futamura Projections in partial evaluation and ISO8631
PAD (Problem Analysis Diagram).
Zenjiro Konishi: He is a visiting lecturer of Institute for Software Production Technology, Waseda University. He received his M. Sc. degree
in mathematics from Waseda University in 1995. His research interests include automated theorem proving. He received JSSST
Takahashi Award in 2001. He is a member of JSSST and IPSJ.
Robert Glück, Ph.D., Habil.: He is an Associate Professor of Computer Science at the University of Copenhagen. He received his Ph.D. and Habilitation
(venia docendi) from the Vienna University of Technology in 1991 and 1997. He was research assistant at the City University of New York
and received twice the Erwin-Schrodinger-Fellowship of the Austrian Science Foundation (FWF). After being an Invited Fellow
of the Japan Society for the Promotion of Science (JSPS), he is now funded by the PRESTO21 program for basic research of the
Japan Science and Technology Corporation (JST) and located at Waseda University in Tokyo. His main research interests are
advanced programming languages, theory and practice of program transformation, and metaprogramming. 相似文献
89.
90.
Kurita H. Shimizu T. Yokoyama H. 《IEEE journal of selected topics in quantum electronics》1996,2(3):508-513
We investigated the detailed characteristics of synchronization of mode-locked laser diodes (MLLD's) by subharmonic optical pulse injection. It was shown that optical harmonic injection mode-locking was not very sensitive to injection pulse shapes. In the time domain, subharmonic injection pulses were multiplexed inside the MLLD and these multiplexed pulses effectively modulated the absorbance of the saturable absorber at the MLLD's repetition frequency. It was also found in the spectral domain that injection pulse trains should have optical spectrum components broader than the MLLD's intermode spacing, and injection spectral components should couple to at least two modes of the MLLD 相似文献