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CdS thin films of about 1 m thickness were deposited from an aqueous solution containing Cd2+, Na2S2O3 and gelatin as the protective colloid to stabilize the size of colloidal sulfur at from 30 to 40 nm and keep the concentration to an appropriate value during electrolysis. The effects of concentrations of Cd2+ and S2O3 2– ions and the deposition potential on the composition of CdS films were studied. The reaction mechanism of CdS film formation on the electrode is discussed. CdS film, whose composition is uniform across the film and which does not contain excess metallic cadmium, can be deposited from a solution containing 0.50 to 2.00 mM Cd(NO3)2, 1.00 to 5.00 mM Na2S2O3 and 1.0 × 10–7 to 1.0 × 10–3 wt % gelatin.  相似文献   
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Measuring the semantic similarity between sentences is an essential issue for many applications, such as text summarization, Web page retrieval, question-answer model, image extraction, and so forth. A few studies have explored on this issue by several techniques, e.g., knowledge-based strategies, corpus-based strategies, hybrid strategies, etc. Most of these studies focus on how to improve the effectiveness of the problem. In this paper, we address the efficiency issue, i.e., for a given sentence collection, how to efficiently discover the top-k semantic similar sentences to a query. The previous methods cannot handle the big data efficiently, i.e., applying such strategies directly is time consuming because every candidate sentence needs to be tested. In this paper, we propose efficient strategies to tackle such problem based on a general framework. The basic idea is that for each similarity, we build a corresponding index in the preprocessing. Traversing these indices in the querying process can avoid to test many candidates, so as to improve the efficiency. Moreover, an optimal aggregation algorithm is introduced to assemble these similarities. Our framework is general enough that many similarity metrics can be incorporated, as will be discussed in the paper. We conduct extensive experimental evaluation on three real datasets to evaluate the efficiency of our proposal. In addition, we illustrate the trade-off between the effectiveness and efficiency. The experimental results demonstrate that the performance of our proposal outperforms the state-of-the-art techniques on efficiency while keeping the same high precision as them.  相似文献   
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The culture characteristics, carotenoid production, and associated biosynthetic pathway of strain T-1 were examined. As a result of examining the culture temperature and light irradiation, an increase of neurosporaxanthin and neurosporaxanthin beta-D-glucopyranoside was observed at a low temperature and 0 lx. It was suggested that highly polar carotenoids, such as neurosporaxanthin, and carotenoid glycosides were involved in the stabilization of membrane during nutrition storage other than the defense function of fungus bodies. Strain T-1 produced lycopene, beta-carotene, gamma-carotene, torulene, neurosporaxanthin, and neurosporaxanthin beta-D-glucopyranoside, as assessed by HPLC, LC-MS, and NMR analysis. Carotenoid biosynthesis begins with neurosporene, passing to lycopene and gamma-carotene through cyclization, and produces beta-carotene. In addition, it is saturated, gamma-carotene is converted to torulene, and neurosporaxanthin is produced. Thus, the carotenoid biosynthetic pathway in strain T-1 was estimated.  相似文献   
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Because the pyrolysis of organic substances can result in the emission of harmful pollutant gases, a reduction in the use of organic binders is one aim of today's ceramics industry. A novel ceramic-forming process was developed that requires considerably less organic binder than conventional techniques. The process involves immobilizing reactive molecules on the surfaces of the particles, which on subsequent irradiation with microwaves, form bridges that bind the entire particle assembly together. The chemical forces involved produce strong bonds, resulting in a significant reduction in the amount of organic binder that is required to maintain the shape of the ceramic green body. This method will help to decrease emissions of harmful gases produced from pyrolysis of the binder.  相似文献   
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Epoxy/zirconia hybrid materials were synthesized via in situ polymerization of acetic acid-modified zirconium alkoxide. The reactivity of acetic acid-modified zirconium alkoxide changed with the amount of acetic acid added. In the hybrid materials, the phase structure varied between the homogeneous phase and nanophase separation as the reactivity of zirconium alkoxide changed. At the molecular level, the storage modulus in the rubbery region significantly increased and the peak area of tan δ in the glass-transition temperature region decreased with increasing zirconia contents in the hybrid dispersed zirconia. Additionally, the optical properties of the hybrid materials in the homogeneous phase were better than those in the system with nanophase separation.  相似文献   
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Abstract: Polyphenols, retained in black tea wastes following the commercial production of tea beverages, represent an underutilized resource. The purpose of this study was to investigate the potential use of hot‐compressed water (HCW) for the extraction of pancreatic lipase‐inhibiting polyphenols from black tea residues. Black tea residues were treated with HCW at 10 °C intervals, from 100 to 200 °C. The resulting extracts were analyzed using high‐performance liquid chromatography‐mass spectrometry and assayed to determine their inhibitory effect on pancreatic lipase activity in vitro. Four theaflavins (TF), 5 catechins, 2 quercetin glycosides, quinic acid, gallic acid, and caffeine were identified. The total polyphenol content of extracts increased with increasing temperature but lipase inhibitors (TF, theaflavin 3‐O‐gallate, theaflavin 3′‐O‐gallate, theaflavin 3,3′‐O‐gallate, epigallocatechin gallate, and epicatechin gallate) decreased over 150 °C. All extracts inhibited pancreatic lipase but extracts obtained at 100 to 140 °C showed the greatest lipase inhibition (IC50s of 0.9 to 1.3 μg/mL), consistent with the optimal extraction of TFs and catechins except catechin by HCW between 130 and 150 °C. HCW can be used to extract pancreatic lipase‐inhibiting polyphenols from black tea waste. These extracts have potential uses, as dietary supplements and medications, for the prevention and treatment of obesity. Practical Application: Active forms of lipase inhibitors can be recovered from black tea residues. They could be used as dietary supplements or medications.  相似文献   
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