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11.
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Chemical components stimulating oviposition bySitophilus zeamais in rice grain were isolated from rice bran and were found to be a mixture of ferulates, diglycerides, and free sterols. Oviposition preference of the species can be induced by synergistic action of these compounds.  相似文献   
13.
A novel chromatographic separation technique using a tertiary pyridine type resin has been applied to the partitioning of the trivalent actinides (An) and lanthanides (Ln) and several successful results have been shown. In an alcoholic hydrochloric acid system, the trivalent An were clearly separated from the Ln, while no such group separation was achieved in an alcoholic nitric acid system. On the other hand, the nitric acid system was more effective for the intragroup (i.e. individual) separation of the trivalent An and the Ln than the hydrochloric acid system. On the basis of these results, a novel concept for the partitioning of the trivalent An and Ln using the present separation technique and its flowchart have been proposed with its advantages and disadvantages.  相似文献   
14.
Osteoporosis is a common bone disease, particularly in menopausal women. Herein, we screened four Kampo medicines (Unkeito (UKT), Kamishoyosan (KSS), Kamikihito (KKT), and Ninjinyoeito (NYT)), frequently used to treat menopausal syndromes, for their effects on receptor activator of nuclear factor-kappaB ligand (RANKL)-induced osteoclast differentiation in RAW 264 cells. Considering that UKT exhibited the most potent effect, we examined its effect on RANKL-induced osteoclastogenesis, the induction of osteoclast apoptosis, and the mechanisms underlying its effects. UKT inhibits RANKL-induced osteoclast differentiation in the early stage and decreases osteoclast-related genes, including tartrate-resistant acid phosphatase (Trap), dendritic cell-specific transmembrane protein (Dcstamp), matrix metalloproteinase-9 (Mmp9), and cathepsin K (Ctsk). Specifically, UKT inhibits the nuclear factor of activated T cells 1 (NFATc1), which is essential for osteoclastogenesis. UKT increases Bcl6, which antagonizes NFATc1 and Dc-stamp, thereby blocking the progression of osteoclasts to maturation. UKT also decreased nuclear translocation by downregulating the activity of p65/NF-κB. In addition, UKT enhances mononuclear osteoclast apoptosis via activation of caspase-3. Herein, we demonstrate that UKT suppresses RANKL-mediated osteoclastogenesis via the Blimp1–Bcl6 and NF-κB signaling pathways and enhances mononuclear osteoclast apoptosis. Furthermore, UKT prevents bone loss in OVX mice. Thus, UKT might be a potential therapeutic agent for postmenopausal osteoporosis.  相似文献   
15.
A combination of macroscale solidification simulation and phase-field calculation is employed to predict the volume fraction of the eutectic phase in Sn-4.0 mass% Ag-XCu solder alloys (X=0.5–1.1 mass%). The solidification simulation incorporates the cooling rate in the phase-field simulation. We assume the residual liquid solidifies as eutectic phase when the driving force for the nucleation of Cu6Sn5 amounts to a critical value, which is determined based on the experimental data. Though the calculation results depend on the experimental data, the obtained fractions are about 40% for 0.5 mass% Cu and more than 90% for 1.1 mass% Cu alloy, which shows good agreement with the experimental data.  相似文献   
16.
Hydrogen is a promising alternative to fossil fuels that can reduce greenhouse gas emissions. Decoupled water electrolysis system using a reversible proton storage redox mediator, where the oxygen evolution reaction and hydrogen evolution reaction are separated in time and space, is an effective approach to producing hydrogen gas with high purity, high flexibility, and low cost. To realize fast hydrogen production in such a system, a redox mediator capable of releasing protons rapidly is required. Herein, α-MoO3, with an ultrafast proton transfer property that can be explained by a dense hydrogen bond network in the lattice oxygen arrays of HxMoO3, is examined as a high-rate redox mediator for fast hydrogen production in acidic electrolytes. The α-MoO3 redox mediator shows both a large capacity of 204 mAh g−1 and fast hydrogen production at a current rate of 10 A cm−2(≈153 A g−1), outperforming most of the previously reported solid-state redox mediators.  相似文献   
17.
This paper describes a single-bit-line cross-point cell activation (SCPA) architecture, which has been developed to reduce active power consumption and to avoid increase in the size of high-density SRAM chips, such as 16-Mb SRAM's and beyond. A new PMOS precharging boost circuit, introduced to realize the single-bit-line structure, is also discussed. This circuit is suitable for operation under low-voltage power supply conditions. The SCPA architecture with the new word-line boost circuit is demonstrated with the experimental device, which is fabricated by a 0.4-μm CMOS wafer process technology  相似文献   
18.
Significant reduction of the contact resistance of In0.7Ga0.3As/Ni/W contacts (which were previously developed by sputtering in our laboratory) was achieved by depositing a W2N barrier layer between the Ni layer and W layer. The In0.7Ga0.3 As/Ni/W2N/W contact prepared by the radio-frequency sputtering technique showed the lowest contact resistance of 0.2 Ωmm after annealing at 550°C for 10 s. This contact also provided a smooth surface, good reproducibility, and excellent thermal stability at 400°C. The polycrystalline W2N layer was found to suppress the In diffusion to the contact surface, leading to improvement of the surface morphology and an increase in the total area of the InxGa−As between metal and the GaAs substrate. These improvements are believed to reduce the contact resistance.  相似文献   
19.
Optical amplifier techniques have led to the installation of large-capacity submarine systems and further capacity increases seem likely. This paper reviews the FSA submarine system, which flexibly operates at both 2.5 and 10 Gb/s and offers maximum transmission capacity of 60 Gb/s for commercial use. The system configuration as well as its characteristics and upgradability will be introduced, including measurement results on time-division-multiplexing/wavelength-division-multiplexing (TDM–WDM) transmission at bit rates of 10 and 20 Gb/s using non-return-to-zero or soliton pulses. To further increase transmission capacity, TDM–WDM techniques that permit more than 10 Gb/s signal transmission in each data channel should be developed. Thus, pulse formats, which include non-return-to-zero, return-to-zero, or soliton pulses, and dispersion allocation in transmission fibers are significant issues. We introduce and discuss our recent results from high-speed (10 to 40 Gb/s) TDM–WDM signal transmission experiments with regard to the above aspects.  相似文献   
20.
In order to prepare low resistance ohmic contacts to p-ZnSn by the “deposition and annealing (DA)” technique which has been extensively used for GaAs and Si-based devices, formation of a heavily doped layer by the p-ZnSe/metal reaction is required. For p-ZnSe/Ni contacts, Ni and Se reacted preferentially at the ZnSe/Ni interface upon annealing at temperatures higher than 250°C. However, capacitance-voltage measurements showed that the net acceptor concentration (NA-ND) close to the p-ZnSe/Ni interface was reduced upon the Ni/ZnSe reaction, resulting in high contact resistance. For p-ZnSe/Au contacts, neither Au/ZnSe reaction nor reduction of the acceptor concentration were observed after annealing at temperatures lower than 300°C. This indicates that although the metal/p-ZnSe reaction is mandatory to prepare a heavily doped layer, the reaction induced an increase in the compensation donors in the p-ZnSe substrate. In order to increase the acceptor concentration in the vicinity of the p-ZnSe/metal interface through diffusion from the contact materials, Li or O which was reported to play the role of an acceptor in ZnSe was deposited with a contact metal and annealed at elevated temperatures. Ni or Ag was selected as the contact metal, because these metals were expected to enhance Li or O doping by reacting with ZnSe. However, the current density-voltage characteristics of the Li(N)/Ni and Ag(O) contacts exhibited rectifying behavior, and the contact resistances increased with increasing annealing temperature. The present results indicated that, even though the acceptor concentration in the p-ZnSe substrate increased by diffusion of the dopants from the contact elements, an increment of the compensation donors was larger than that of the acceptors. The present experiments indicated that preparation of low resistance ohmic contacts by forming a heavily doped intermediate layer between p-ZnSe and metal is extremely difficult by the DA technique.  相似文献   
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