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151.
A database for the thermophysical properties of hydrogen that supports a wide range of parameters including high pressures and high temperatures is being developed. The database performance requirements were studied and, in this paper, an application that combines a server–client database and a live CD is proposed. For this, an “All in One Live CD” application has been developed. Web interfaces provide excellent user interfaces for databases. However, there are some disadvantages for web interfaces related to server maintenance and access restrictions. This new application, the “All in One Live CD,” is free of these disadvantages, and provides a database with a property estimation service independent of the computer environment. From a single boot via the “All in One Live CD,” the database becomes accessible on multiple computers so that this feature makes the new application a unique solution as a distribution media.  相似文献   
152.
A multicore system-on-chip (SoC) has been developed for various applications (recognition, inference, measurement, control, and security) that require high-performance processing and low power consumption. This SoC integrates three types of synthesizable processors: eight CPUs (M32R), two multi-bank matrix processors (MBMX), and a controller (M32C). These processors operate at 1 GHz, 500 MHz, and 500 MHz, respectively. These three types of processors are interconnected on this chip with a high-bandwidth multi-layer system bus. The eight CPUs are connected to a common pipelined bus using a cache coherence mechanism. Additionally, a 512-kB L2 cache memory is shared by the eight CPUs to reduce internal bus traffic. A multi-bank matrix processor with 2-read/1-write calculation and background I/O operation has been adopted. The 1-GHz CPU is realized using a delay management network which consists of delay monitors that can be applied for any kind of application or process technology. Our configurable heterogeneous architecture with nine CPUs and two matrix processors reduces power consumption by 45%.  相似文献   
153.
Copper aluminum disulfide (CuAlS2) powders were synthesized in the evacuated ampoule. The luminescence properties of obtained powders were evaluated by photoluminescence (PL) at various temperatures. The visible emission peaks at 2.16 and 1.90 eV, and weak ultraviolet emission peak at 3.47 eV were obtained in the room temperature PL. The temperature dependence of the PL revealed that the ultraviolet emission at room temperature was considered to be free-exciton. Several emission peaks related to free-exciton, bound-exciton and phonons were observed in the high-resolution PL at 12 K, reflecting that the obtained powders had high crystallinity. Emission peaks at 3.459 and 3.300 eV for CuAlS2 were observed for the first time. The former emission might be originated from the bound exciton and the latter from the donor–acceptor pair recombination.  相似文献   
154.
Purification and gene cloning of a chitosanase from Bacillus ehimensis EAG1   总被引:3,自引:0,他引:3  
Bacillus ehimensis EAG1 (IFO15659) produced and secreted chitosanase in the presence of exogenous chitosan. The chitosanase was purified from the culture filtrate of the bacterium to apparent homogeneity in SDS-polyacrylamide gel electrophoresis. The purified enzyme had a molecular weight of approximately 31,000. A 1.9-kbp DNA fragment containing the chitosanase gene was cloned and the complete nucleotide sequence was determined. The sequence was found to contain a single open reading frame encoding a protein of 302 amino acids. The deduced amino acid sequence showed significant homology with the chitosanase from Bacillus circulans MH-K1.  相似文献   
155.
156.
Uromodulin, a urinary protein synthesized and secreted from the thick ascending limb (TAL) of the loop of Henle, is associated with hypertension through the activation of sodium reabsorption in the TAL. Uromodulin is a potential target for hypertension treatment via natriuresis. However, its biological function in epithelial cells of the distal nephron segment, particularly the collecting duct, remains unknown. Herein, we examined the regulation of uromodulin production during water deprivation in vivo as well as the effect of uromodulin on the activity of the water channel aquaporin−2 (AQP2) in vitro and in vivo using transgenic mice. Water deprivation upregulated uromodulin production; immunofluorescence experiments revealed uromodulin adhesion on the apical surface of the collecting duct. Furthermore, the activation of AQP2 was attenuated in mice lacking uromodulin. Uromodulin enhanced the phosphorylation and apical trafficking of AQP2 in mouse collecting duct cells treated with the vasopressin analog dDAVP. The uromodulin-induced apical trafficking of AQP2 was attenuated via endocytosis inhibitor treatment, suggesting that uromodulin activates AQP2 through the suppression of endocytosis. This study provides novel insights into the cross−talk between TAL and the collecting duct, and indicates that the modulation of uromodulin is a promising approach for diuresis and hypertension treatment.  相似文献   
157.
We report a dramatic and irreversible reduction in the lattice thermal conductivity of bulk crystalline silicon when subjected to intense plastic strain under a pressure of 24 GPa using high-pressure torsion (HPT). Thermal conductivity of the HPT-processed samples were measured using picosecond time domain thermoreflectance. Thermal conductivity measurements show that the HPT-processed samples have a lattice thermal conductivity reduction by a factor of approximately 20 (from intrinsic single crystalline value of 142 Wm−1 K−1 to approximately 7.6 Wm−1 K−1). Thermal conductivity reduction in HPT-processed silicon is attributed to the formation of nanograin boundaries and metastable Si-III/XII phases which act as phonon scattering sites, and because of a large density of lattice defects introduced by HPT processing. Annealing the samples at 873 K increases the thermal conductivity due to the reduction in the density of secondary phases and lattice defects.  相似文献   
158.
159.
The optically coupled three-dimensional common (3D-OCC) memory is an intelligent memory for a real-time parallel processor system. It consists of a multilayered structure of two-dimensional memory with LEDs and photoconductors. The memory layers are optically coupled with each other through the LEDs and the photoconductors. Data are transferred in the vertical direction by optical coupling, while the conventional memory operations are performed in the horizontal planes. Very fast optical data transfer of 32 Gb/s/layer is confirmed in the simulation  相似文献   
160.
A concatenated coded modulation scheme is presented for error control in data communications. The scheme is achieved by concatenating a Reed-Solomon outer code and a bandwidth efficient block inner code for M-ary phase-shift keying (PSK) modulation. Error performance of the scheme is analyzed for an additive white Gaussian noise (AWGN) channel. It is shown that extremely high reliability can be attained by using a simple M-ary PSK modulation inner-code and a relatively powerful Reed-Solomon outer code. Furthermore, if an inner code of high effective rate is used, the bandwidth expansion required by the scheme due to coding will be greatly reduced. The scheme is particularly effective for high-speed satellite communications for large file transfer where high reliability is required. A simple method is also presented for constructing block codes for M-ary PSK modulation. Soome short M-ary PSK codes with good minimum squared Euclidean distance are constructed. These codes have trellis structure and hence can be decoded with a soft-decision Viterbi decoding algorithm. Furthermore, some of these codes are phase invariant under multiples of 45° rotation  相似文献   
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