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31.
Quinolinate (Quin), a metabolite in the kynurenine pathway of tryptophan degradation and a neurotoxin that appears to act through the N-methyl-D-aspartate receptor system, was localized in cultured human peripheral blood monocytes/macrophages (PBMOs) by using a recently developed immunocytochemical method. Quin immunoreactivity (Quin-IR) was increased in gamma interferon (IFN-gamma)-stimulated monocytes/macrophages (MOs). In addition, the precursors, tryptophan and kynurenine, significantly increased Quin-IR. Infection of MOs by human T-cell lymphotropic virus type I (HTLV-I) in vitro substantially increased both the number of Quin-IR cells and the intensity of Quin-IR. At the peak of the Quin-IR response, about 40% of the cells were Quin-IR positive. In contrast, only about 2-5% of the cells were positive for HTLV-I, as detected by both immunofluorescence for the HTLV-I antigens and PCR techniques for the HTLV-I Tax gene. These results suggest that HTLV-I-induced Quin production in MOs occurs by an indirect mechanism, perhaps via cytokines produced by the infection but not directly by the virus infection per se. The significance of these findings to the neuropathology of HTLV-I infection is discussed.  相似文献   
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Search and retrieval is gaining importance in the ink domain due to the increase in the availability of online handwritten data. However, the problem is challenging due to variations in handwriting between various writers, digitizers and writing conditions. In this paper, we propose a retrieval mechanism for online handwriting, which can handle different writing styles, specifically for Indian languages. The proposed approach provides a keyboard-based search interface that enables to search handwritten data from any platform, in addition to pen-based and example-based queries. One of the major advantages of this framework is that information retrieval techniques such as ranking relevance, detecting stopwords and controlling word forms can be extended to work with search and retrieval in the ink domain. The framework also allows cross-lingual document retrieval across Indian languages.  相似文献   
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An extracellular 1,3-specific lipase with molecular weight of 35.5 kDa and an isoelectric point of 4.4 from Aspergillus niger has been purified 50-fold by pH precipitation followed by a series of chromatographic steps with an overall yield of 10%. The enzyme was homogeneous as judged by denaturing polyacrylamide gel electrophoresis and size-exclusion fast-performance liquid chromatography. It contained 2.8% sugar which was completely removed by endoglycosidase F treatment, and the deglycosylated enzyme retained full activity. The native lipase showed optimal activity between temperatures 35 and 55°C and pH 5.0 and 6.0. The amino acid composition and the N-terminal sequence were found to be different from lipases previously purified from A. niger. The enzyme was resistant to trypsin, chymotrypsin, endoprotease Glu-C, thrombin, and papain under native conditions but was susceptible to cleavage by the same proteases when heat-denatured.  相似文献   
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Eighteen compositions of MoO3-Te at 800 °C and seven of each of MoO3-Cd (at 500 °C) and MoO3-Sb (at 600 °C) were heat treated in vacuum-sealed quartz ampules. The phases of the heat-treated compositions were analyzed using x-ray diffraction (XRD) patterns. The interactions in the three systems are summarized. Three phases in equilibrium are (1) in the MnO3-Te system at 800 °C, Te, Mo4O11, TeMo4O13—(0<xMoO 3<0 889) and MoO3, Mo4O11, TeMo4O13—(0.889<xMoO 3<1); (2) in the MoO3_Cd system at 500 °C, Cd, MoO2, CdMoO4—(0<xMoO 3<0.6667) and MoO3, MoO2, CdMoO4—(0.6667<xMoO 3<1); and (3) in the MoO3-Sb system at 600 °C, Sb, MoO2, Sb4Mo10O31—(0<xMoO 3<0.734) and MoO3+MoO2+Sb4Mo10O31 (0.734<xMoO 3<1). The results lead to construction of ternary phase diagrams: Te-MoO3-TeMo4O13, Cd-MoO3-CdMoO4, and Sb-MoO3-Sb4Mo10O31.  相似文献   
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The mechanical properties of components manufactured by fused filament fabrication lack sufficient levels for industrial applications. The need for post-processing is, therefore, necessary to enhance the interlayer strength and mechanical characteristics. In the present study, experimental analysis of the effects of annealing on polycarbonate acrylonitrile butadiene styrene manufactured by fused filament fabrication is explored. Annealing temperatures are selected in the range from 90 to 210°C based on differential scanning calorimetry analysis. The ultimate tensile strength improved by 20.39% from 32.39 to 38.99 MPa after the heat treatment at 180°C for 1-h duration. Flexural strength showed a remarkable enhancement of 53.21% after annealing at 180°C for 2 h. The interlayer diffusion and bonding are boosted following heat treatment and microstructural imaging proved the same although the surface had flakes due to the high heat exposure. X-ray diffraction testing of annealed models demonstrated a maximum crystallinity index of 32.56% when compared with nonannealed samples with 6.58%. The addition of polycarbonate to acrylonitrile butadiene styrene improves the stiffness and impact loading capacity with high heat resistance. The heat treatment process is capable of magnifying the mechanical characteristics of the end functional components, thereby opening up the scope for more engineering applications.  相似文献   
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