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71.
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Abstract

This study focused on the development of woven structures based on leno weave with tailored performance properties. To achieve this objective, pure leno and hybrid leno weaves were used to produce woven fabrics. In hybrid weaves, leno weave was combined with 1/1 plain, 3/1 twill, and 2/2 matt weaves, and 12 samples were produced with three different weft thread densities. The multifilament polyester yarn was used as warp and weft material. The characterization of physical and mechanical properties showed that comparable tensile properties were achieved by leno and hybrid weave fabrics, but the hybrid structures offered lower resistance to puncture as compared to pure leno fabrics. A multi-response optimization technique was used to determine the best sample under a particular set of conditions.  相似文献   
73.
The action of water in natural fiber-reinforced composite material was studied so as to produce great swelling with resultant changes in the fine structure, dimensional stability, and mechanical properties. Water absorption and thickness swelling test reveal that hybrid composite shows water absorption moderately, which is 15.3% for hybrid coir/jute/coir composite and 11.2% for hybrid jute/coir/jute composite. The thickness swelling, water absorption, and mechanical properties of the hybrid composites slightly increased as the layering pattern of hybrid composites changed. Hybridization of coir fibers composites with jute fibers can improve the dimensional stability, extensibility and density of pure coir composites. Microstructures of the composites were examined to understand the mechanisms for the fiber-matrix interaction in relation to mechanical properties.  相似文献   
74.
In this work, we report a detailed study of the formation of hollow nanostructures in iron oxides. Core/shell Fe/Fe-oxide nanoparticles were synthesized by thermal decomposition of Fe(CO)(5) at high temperature. It was found that 8 nm is the critical size above which the particles have a core/shell morphology, whereas below this size the particles exhibit a hollow morphology. Annealing the core/shell particles under air also leads to the formation of hollow spheres with a significant increase in the average particle size. In the case of the thermally activated Kirkendall process, the particles do not fully transform into hollow structures but many irregular shaped voids exist inside each particle. The 8 nm hollow particles are superparamagnetic at room temperature with a blocking temperature of 70 K whereas the core/shell particles are ferromagnetic.  相似文献   
75.
Glomerella leaf spot (GLS), caused by the fungus Colletotrichum fructicola, is one of the most devastating apple diseases. Our previous study reported that the GLS resistance locus was defined on the chromosome 15 region. Here, we further found a single-nucleotide polymorphism (SNP) site (SNP7309212) in the GLS resistance that was able to distinguish resistant cultivars (lines) from susceptible ones. On the basis of the SNP site, we cloned a TNL gene from the GLS resistant locus and named it MdTNL1 (NCBI Accession Number: ON402514). This gene contains a toll/interleukin-1 receptor transmembrane domain (TIR), nucleotide-binding sites (NBS), and leucine-rich repeat (LRR) domain. Subcellular location indicated that MdTNL1 was expressed in the nucleus and cell membrane. Ectopic overexpression of MdTNL1 in Nicotiana benthamiana caused cell death. We further demonstrated allelic polymorphisms in MdTNL1. It is noteworthy that NBS and LRR domains of the MdTNL1 protein serve as the repository for generating allelic diversity. Quantitative real-time PCR (qRT-PCR) assay revealed that MdTNL1 was highly expressed in resistant apple cultivar ‘Fuji’ after inoculation with C. fructicola, whereas susceptible cultivar ‘Golden Delicious’ exhibited low expression after inoculation. Over-expression of MdTNL1-1 in susceptible apple fruits and leaves improved disease resistance, while in ‘Orin’ calli, silencing the MdTNL1-1 gene conversely decreased GLS resistance. In conclusion, we identified a GLS associated with SNP7309212 and demonstrated that a TIR-NBS-LRR gene MdTNL1-1 positively regulates GLS resistance in apple.  相似文献   
76.
We investigated the simultaneous production of xylanase and the liberation of xylooligosaccharides in rice husk solid‐state cultivations of Aspergillus brasiliensis BLf1 and by the recombinant Aspergillus nidulans XynC A773 strain. The bioprocess was optimised by experimental fractional design and response surface analysis. Results show that both fungi strains produced xylanases and their activities were dependent on the addition of basal medium, moisture content and the interactions between particle size and inoculum size, producing maximum xylanase activities of 230.7 U g?1 substrate for A. brasiliensis, and 187.9 U g?1 substrate for A. nidulans XynC. Xylooligosaccharides were liberated in the same cultures, with concentrations up to 17.6 mg g?1 and 23.9 mg g?1 of substrate for A. brasiliensis and A. nidulans XynC, respectively, both strains presenting similar profiles, with xylose residues varying from X3 to X6. These results suggest the possibility of lowering production costs of enzymes for food applications and oligosaccharides.  相似文献   
77.
A lot of technical information/data is generated daily at a Nuclear Power Plant (NPP). More often than not this information is scattered over different forms, data sheets and reports. As such, accessibility as well as useability is limited. In order to make this information useable and beneficial to plant safety and availability, PC based software was developed in-house. This paper describes the software and its benefits that have been seen.  相似文献   
78.
The frequency, position, and type of errors were analyzed for sequence data which were generated with the help of (I) a manual digitizer, (II) an off-line automated film reader, and (III) an on-line automated gel reader. About 400 film/gel readings were analyzed and the results were used to generate error profiles for each method. The profiles identify several method- and project-specific problem areas and provide useful guidance for the assessment of DNA sequence data in general.  相似文献   
79.
OBJECTIVE: Recent studies have suggested that chronic infections may be a risk factor for coronary artery disease. The aim of this study was to determine whether Helicobacter pylori (H. pylori) infection was an independent risk factor for coronary artery disease. METHODS: A total of 179 patients undergoing coronary angiography for suspected coronary artery disease were prospectively studied. Angiograms were read by experienced invasive cardiologists blinded to the results of H. pylori serology, which was determined by a validated multiwell ELISA assay. RESULTS: A total of 121 patients (68%) had evidence of coronary artery disease, whereas 58 patients (32%) had normal coronary angiograms. Of the 121 patients with coronary artery disease, 29 had single vessel disease, 39 had double vessel disease, and 53 had triple vessel disease, respectively. There was no significant difference in seroprevalence of H. pylori infection in patients with and without coronary artery disease (p = 0.63). The odds ratio (after adjustment for other known risk factors) for coronary artery disease in H. pylori-infected subjects was 0.45 (95% CI = 0.15, 1.37; p = 0.107). In patients with coronary artery disease, H. pylori infection did not increase the likelihood of severe disease (odds ratio for triple vessel disease = 0.53; 95% CI 0.18, 1.60; p = 0.201). CONCLUSION: H. pylori infection rates are similar in patients with normal and abnormal coronary arteries, and infection with H. pylori is not an independent risk factor for coronary artery disease. In patients who have coronary artery disease, H. pylori infection is not a risk factor for more severe disease. These data argue against a causal role for H. pylori in the pathogenesis of coronary artery disease.  相似文献   
80.
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