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51.
After hepatectomy, purine and pyrimidine metabolism is a key process in the synthesis of DNA and RNA and maintaining cellular energy metabolism. The purpose of this study is to evaluate changes in blood purine and pyrimidine levels after partial hepatectomy and the effect of purine and pyrimidine nucleoside solution injection on hepatic regeneration under the hypothesis that the rat after partial hepatectomy requires substrates for salvage nucleotide synthesis and changes blood nucleoside and nucleobase levels. Blood levels of nucleotides, nucleosides, and nucleobase by high-performance liquid chromatography method and liver ATP level by enzymatic analysis, and the effect of preoperative injection of nucleoside solution (OG-VI) on hepatic regeneration ratio and hepatocytes DNA synthesis, were assessed in rats after 70% partial hepatectomy. Decreased liver adenosine triphosphate and increased plasma xanthine and hypoxanthine after partial hepatectomy indicated an increase in catabolism of purine nucleotides in regenerating liver. Plasma thymidine and cytidine levels increased, then returned to the prevalue, suggesting that the thymidine and cytidine pool was enlarged. OG-VI increased labeling indices of hepatocytes at postoperative d 1 (POD) and hepatic regeneration ratio at POD 14. Blood purine nucleobase and pyrimidine nucleoside levels change after partial hepatectomy and preoperative supply of nucleoside solution is effective for increasing hepatocytes DNA synthesis and hepatic regeneration after partial hepatectomy.  相似文献   
52.
A divide-by-256/258 dual-modulus prescalar IC has been successfully fabricated using enhancement-mode GaAs JFETs. The maximum operation frequency of 10.4 GHz is obtained by a 0.5 mu m gate length and buried p-layer JFET technology. The prescalar IC has sufficient operational margin to make it compatible with Si bipolar ECL circuits over a wide frequency range.<>  相似文献   
53.
Discrete-time Wiener-Hopf equations (DTWHEs) over finite fields are considered. It is shown that solving the DTWHE is equivalent to performing division over finite fields. The proof provides a new interpretation of the relationship between bit-serial multiplication and DTWHEs. The interpretation enables bit-serial multiplication over GF(2 m) to be understood more easily. As an example, bit-serial multiplication methods for multiplying any two elements that can be done without performing any transformation, or with only a simple transformation of the bases, are presented  相似文献   
54.
Self-diffusion coefficients and viscosities for the saturated hydrocarbons having six carbon atoms such as hexane, 2-methylpentane (2MP), 3-methylpentane (3MP), 2,2-dimethylbutane (22DMB), 2,3-dimethylbutane (23DMB), methylcyclopentane (McP) and cyclohexane (cH) were measured at various constant temperatures; obtained results were discussed in connection with their molar volumes, molecular structures and thermodynamic properties. The values of self-diffusion coefficients as the microscopic property were inversely proportional to those of viscosities as the macroscopic property. The order of their viscosities was almost same to those of their melting temperatures and enthalpies of fusion, which reflect the attractive interactions among their molecules. On the other hand, the order of the self-diffusion coefficients inversely related to the order of the melting temperatures and the enthalpies of the fusion. Namely, the compound having the larger attractive interaction mostly shows the less mobility in its liquid state, e.g., cyclohexane (cH), having the largest attractive interaction and the smallest molar volume exhibits an extremely large viscosity and small self-diffusion coefficient comparing with other hydrocarbons. However, a significant exception was 22DMB, being most close to a sphere: In spite of the smallest attractive interaction and the largest molar volume of 22DMB in the all samples, it has the thirdly larger viscosity and the thirdly smaller self-diffusion coefficient. Consequently, the dynamical properties such as self-diffusion and viscosity for the saturated hydrocarbons are determined not only by their attractive interactions but also by their molecular structures.  相似文献   
55.
In order to better understand the influence of the shape of solid particles on the stability of liquid marbles, we investigated liquid marbles stabilized by hydrophobized calcium carbonate particles with spherical and rod-shaped morphologies. Static properties, such as the effective surface tension, and the dynamic behavior i.e. the compression-decompression features for several cycles of the liquid marbles were investigated. Liquid marbles stabilized with spherical CaCO3 particles show an elastic response to mechanical deformation almost up to collapse. In contrast, liquid marbles prepared with rod-like particles exhibit a more plastic response to compression. It is concluded that the main differences in behavior of the prepared liquid marbles arise from how the solid particles can arrange/orient at the air/water interface.  相似文献   
56.
A 13-year-old warmblood mare was presented because of progressive weight loss, general weakness and trembling. On examination the horse stood with its head lowered and the limbs placed under the body. On lifting its head spasms of the neck muscles could be observed. At the same time the horse developed trembling over the lower neck and muscle fasciculations continued over the whole body. Additional signs included frequent recumbency, polyphagia and facial hyperaesthesia. The horse showed no signs of ataxia. Haematology was normal. Blood biochemistry revealed slight increased aspartate aminotransferase (AST: 1060 U/I) and creatine kinase levels (CK: 441 U/I). Based on the clinical findings equine motor neuron disease was diagnosed. The horse was euthanatized due to poor prognosis and the progression of symptoms. The typical neurodegenerative changes found on histological examination of the spinal cord confirmed the diagnosis.  相似文献   
57.
A key equation of the remainder decoding algorithm is presented. It is noted that the key equation presents a general relationship between the errors on the received codeword and the coefficients of the remainder polynomial. It is shown that several key equations proposed by L. Welch and E.R. Berlekamp (1983) and others can be derived from the proposed key equation. Useful properties of the key equations in fast decoding of Reed-Solomon codes are given  相似文献   
58.
Duplicate dentures were made from heat-cured (HC) and microwave-cured (MC) bases, and with these bases reinforced with glass cloth. The clearance as a dimensional change in the resins was measured in relation to duplicate gypsum models from a master denture model. The clearance value in resins stored in distilled water at 37°C demonstrated better dimensional accuracy as compared with base resin replicas stored in air at 37°C. When measured at 1 kg load, MC and HC base resins showed a decrease in the clearance value. MC and HC resins reinforced with glass cloth had no significant difference between the values of dimensional accuracy at each site. The MC base and reinforced resins could be useful, comparable with HC acrylic base resin, for dental applications.  相似文献   
59.
60.
We propose a novel structure that reduces the switching power of a silica-based thermooptic switch (TOSW). The structure consists of silicon trenches and heat insulating grooves, which are formed beneath and beside the arms of a Mach-Zehnder interferometer, respectively. We optimize the structure using the differential-element method (DEM) and fabricate a 2 × 2 TOSW with a switching power of only 90 mW, namely, 75% less than that of a conventional TOSW. We also obtain an insertion loss of about 1 dB and an extinction ratio of over 30 dB with a response time from 0% to 90% of 4.9 ms. We then use the structure to fabricate an 8 × 8 matrix switch and confirm a total power consumption of 1.4 W with an average insertion loss of 7.4 dB and an extinction ratio of 50.4 dB for 64 possible optical paths  相似文献   
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