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71.
Joint spatial-temporal signal processing has been recognized as the key to reducing the effects of the intersymbol and cochannel interference seen in very high bit-rate mobile radio communications systems. Developing hardware simulators that can simulate mobile radio propagation scenarios in time and space domains is essential for evaluating the real-time performance of spatial-temporal signal processing schemes. This paper outlines a complex baseband platform developed for spatial-temporal mobile radio channel simulations. The platform consists of a complex baseband fading/array response simulator, a digital signal processor (DSP) board, and a general-purpose parameter estimator that uses systolic array implementation of the recursive least square (RLS) algorithm. Results of experiments conducted using the developed platform are presented to confirm the proper operation of the system.  相似文献   
72.
This article discusses a new division algorithm for computers which is cost effective and which can be implemented with a table of manageable size. Recent reports of a new convergence division process (Asai (1980), Asai and Cheng (1983)) only describe a mathematical process. The practical advantages of the new convergence division are discussed here and the old and new convergence divisions are compared. The new method promises to reduce the performance time and table size required for convergence division.  相似文献   
73.
The reliability of Cu interconnects was successfully improved by applying a CuAl alloy seed. However, the effect of additive Al on the reliability is not fully understood. In order to reveal the reliability improvement mechanism, Cu films using CuAl alloy seed were investigated in detail. As stress induced voiding (SIV) as well as electromigration is caused by migration of vacancies and/or Cu atoms, the measured activation energy value of electromigration using CuAl indicates that the fast diffusion paths are Cu grain boundaries. The analysis using high lateral resolution scanning type secondary ion mass spectrometry (nano-SIMS) clarifies that additive Al in ECP-Cu film is mainly localized at grain boundaries. Furthermore, positron annihilation was used to probe vacancy-type defects in Cu films. The CuAl films before recrystallization contain larger and higher density vacancy-type defects. Whereas, the recrystallized CuAl films after annealing above 250 °C contain smaller and lower density defects. Furthermore, CuAl films with annealing above 350 °C contain less Al inside the grains. These results represent that Al atoms in Cu films with annealing above 350 °C are exhausted from inside grains to the grain boundaries, and the spewed Al atoms existing at Cu grain boundary effectively prevents the diffusion of Cu and/or vacancies.  相似文献   
74.
A total of 353 samples of 29 types of seafood were tested for Salmonella prevalence and total microbial population. Salmonella enterica serotype Weltevreden was isolated from 2 of 47 black tiger prawn samples. The contamination levels of Salmonella were in a range of <30 to 40 most probable number per 100 g. In addition, one sample of black tiger prawns and two samples of white shrimp were positive for Salmonella invA gene on PCR assay. Although the mean aerobic bacterial count was greater than 4 log CFU/g in most of the sample types, those in the two Salmonella-isolated samples of black tiger prawn were 7.48 and 5.18 log CFU/g, respectively. These results indicate the possibility that shrimp and prawns contribute to foodborne infections. The improvement of seafood quality is an important issue, and the information on contamination by pathogens should be provided as feedback to the originating country, with the aim of increasing safety.  相似文献   
75.
Protein affinity reagents (e.g., antibodies) are often used for basic research, diagnostics, separations, and disease therapy. Although a lot of “synthetic” protein affinity reagents have been developed as a cost-effective alternative to antibodies, their low biocompatibility is a considerable problem for clinical application. Lipid nanoparticles (LNP) represent a highly biocompatible drug delivery agent. However, little has been reported that LNP itself works as a protein affinity reagent in living animals. Here, LNP is engineered for binding to and neutralizing a target toxic peptide in living animals by multifunctionalization with amino acid derivatives. Multifunctionalized LNP (MF-LNP) is prepared using amino acid derivative-conjugated lipids. Optimized MF-LNP exhibits nanomolar affinity to the target toxic peptide and inhibits toxic peptide-dependent hemolysis and cytotoxicity. In addition, MF-LNP captures and neutralizes the toxic peptide after intravenous injection in the bloodstream; in addition, MF-LNP does not release the toxic peptide in the accumulated organ. These results reveal the potential of using LNP as a highly biocompatible protein affinity reagent such as an antidote.  相似文献   
76.
One of the UNESCO intangible cultural heritages Bunraku puppets can play one of the most beautiful puppet motions in the world. The Bunraku puppet motions can express emotions without the so-called ‘Uncanny Valley.’ We try to convert these emotional motions into robot affective motions so that robots can interact with human beings more comfortable. In so doing, in the present paper, we present a robot motion design framework using Bunraku affective motions that are based on the so-called ‘Jo-Ha-Kyū,’ and convert a few simple Bunraku motions into a robot motions using one of deep learning methods. Our primitive experiments show that Jo-Ha-Kyū can be incorporated into robot motion design smoothly, and some simple affective robot motions can be designed using our proposed framework.  相似文献   
77.
ABSTRACT

Charged Particle Activation Analysis (CPAA) utilizing an 8-MeV proton beam has been studied for determination of 35 long-lived radioactive nuclides. We accumulated the reaction cross section and nuclear decay data by referring to nuclear database supplied by National Nuclear Data Center in Brookhaven National Laboratory. We also calculated the reaction cross sections by using statistical model code ALICE. By using the nuclear data, we have derived determination sensitivity of the radioactive nuclides relative to unit weight and specific radioactivity. The result indicates that several hardly measurable nuclides with long half-lives such as 135Cs, 244Pu, 129I, 126Sn, 93Mo, 107Pd, 236U, 248Cm, and 237Np have high sensitivity. It may be concluded that CPAA can be applied to determination of several long-lived nuclei and will provide a quick and non-destructive analysis method.  相似文献   
78.
79.
Double-Pass-Pumped Tm:YAG Laser with a Simple Cavity Configuration   总被引:1,自引:0,他引:1  
Sato A  Asai K  Itabe T 《Applied optics》1998,37(27):6395-6400
For a double-pass-pumped cw Tm:YAG laser, we developed a theoretical model, taking into account reabsorption loss and mode matching between the pumping light and the cavity mode. We also demonstrated that efficient operation can be obtained with a simple cavity configuration by using a dichroic output mirror, highly reflective at the pumping wavelength and partially reflective at the lasing wavelength. Experimental comparisons of this pumping method with single-pass pumping showed that the longitudinally double-pass-pumped Tm:YAG laser performs as well at room temperature as the single-pass-pumped laser performs at -10 degrees C.  相似文献   
80.

Scintillators, which are widely used as radiation detectors, are phosphors that release absorbed ionizing radiation energy as ultraviolet or visible light. Inorganic glass scintillators have several advantages over inorganic crystal scintillators, such as ease of fabrication and low costs. However, unlike inorganic crystals, which can emit up to tens of thousands of photons/MeV, inorganic glasses exhibit less than several hundred photons/MeV in most cases. Here, we studied an inorganic glass scintillator that exhibits a light yield of 2700 photons/MeV, which exceeds those of previous inorganic glass scintillators with high light yields of approximately 2000 photons/MeV. The density of this material is 3.28 g/cm3, which is relatively high among glass scintillators. Moreover, a fast scintillation decay with a decay time constant of 30.0 ns was obtained and is attributed to the 5d–4f transition of Ce3+. Thus, this glass is suitable for gamma- and X-ray detection, thereby expanding the practical applicability of inorganic glass scintillators.

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