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131.
We make a proposal about the microcapsule diffuser screen with the purpose of reducing the speckle noise on a laser display. This microcapsule diffuser screen has a screen surface in which microcapsules containing charged diffuser particles are applied, where an electric field is charged from the outside, and, thus, the diffuser particles in the capsule are randomly agitated to reduce the speckle noise. In this paper, the speckle noise reducing effect of this screen is studied as well as the reducing effect with respect to the conditions such as the drive conditions and amount of the diffuser particle in the microcapsule.  相似文献   
132.
Using the one-way effect extraction method, this paper presents a set of partial causal measures which represents quantitatively the interdependence between a pair of vector-valued processes in the presence of a third process. Those measures are defined for stationary as well as for a class of non-stationary time series. In contrast to conventional conditioning methods, the partial concept defined in the paper would be mostly devoid of feedback distortion by the third process. The paper also discusses statistical inference on the proposed measures.  相似文献   
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134.
Anthocyanins are a group of natural occurring pigments responsible for the red-blue color of grapes and many fruits and vegetables. Anthocyanins and derived pigments are of double interest, one technological, as they can be used as natural colorants, and another one due to their implication on human health through their antioxidant activity. Although there are numerous studies regarding the antioxidant activity of grape extracts as well as red wine, the free radical scavenging activity of purified anthocyanins and pyranoanthocyanins is largely unknown. In the present study, the hydroxyl and superoxide anion scavenging activities of anthocyanins and their pyruvic acid adducts were systematically investigated by electron spin resonance spectroscopy and spin trapping. The 3-glucosides of delphinidin, cyanidin, petunidin, pelargonidin and malvidin, and the pyruvic adduct of the 3-glucoside of delphinidin exhibited a potent superoxide anion radical scavenging and, to a lesser extent hydroxyl anion radical scavenging activity. The pyranoanthocyanins of cyanidin, petunidin, malvidin and pelargonidin showed a high capacity to scavenge superoxide anion radicals but did not scavenge hydroxyl radicals. Current data indicate that formation of anthocyanin adducts with pyruvic acid, which may occur during wine ageing or fruit juice processing, decreases the hydroxyl and superoxide anion scavenging and thus could decrease the antioxidant potential of these compounds.  相似文献   
135.
BACKGROUND: Fermented rice flour (khao‐khab, a non‐glutinous rice) and related products are Thai traditional products. The types of acetic acid bacteria (AAB) microflora in khao‐khab have not been reported. In this study, Acetobacter strains were isolated and identified based on the phenotypic and chemotaxonomic characteristics and molecular aspects. RESULTS: Twenty‐five acetic acid bacteria isolated from fermented rice products and a starter for sweetened rice in Thailand by an enrichment culture approach, were assigned to the genus Acetobacter by phenotypic and chemotaxonomic characterisations. On the basis of the 16S rRNA gene sequence and 16S–23S rRNA gene ITS restriction analyses, 25 isolates were divided into six groups and identified at the specific level: (1) Group 1 included five isolates, which were identified as A. indonesiensis; (2) Group 2 included two isolates, which were identified as A. lovaniensis; (3) Group 3 included one isolate, which was identified as A. orientalis; (4) Group 4 included eleven isolates, which were identified as A. pasteurianus; (5) Group 5 included three isolates, which were identified as A. syzygii and (6) Group 6 included three isolates, which were unidentified and considered to constitute a new species. CONCLUSION: Results revealed that various Acetobacter species were distributed in Thai fermented rice flour and related products. A novel Acetobacter species was isolated from the product. Copyright © 2011 Society of Chemical Industry  相似文献   
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137.
We have been developing a high-performance liquid chromatography/photodiode array (HPLC/PDA) employing relative molar sensitivities (RMSs) and adopted it to the accurate quantification of carnosol (CL) and carnosic acid (CA) which are the antioxidants in rosemary extract. The method requires no references of CL or CA and instead uses RMSs with respect to diphenylamine (DPA) whose certified reference material is available from a reagent manufacturer. The molar and response ratios of the analytes to the reference in an artificial mixture of them were determined using 1H-quantitative nuclear magnetic resonance spectroscopy (1H-qNMR) and HPLC/PDA at a wavelength of 284 nm under isocratic condition, respectively, and then RMSs were calculated to be 0.111 for CL/DPA and 0.0809 for CA/DPA as averaged values in three HPLC–PDA instruments. The RMS values varied by up to 1.1% as relative standard deviation. To evaluate the performance of HPLC/PDA with the RMSs, the CL and CA contents in rosemary extracts were determined using DPA as a reference. The CL and CA contents were compared with those determined using calibration curves of CL and CA obtained by HPLC measurement of standard solutions prepared from their reagents whose absolute purities were determined using 1H-qNMR. The differences between the two methods for CL and CA were ≤3% as relative error. This chromatographic method with RMSs allows a simple and reliable quantification when reference of the analyte is unavailable.  相似文献   
138.
Enzymatic acidolysis and glyceride synthesis using polyunsaturated fatty acids (PUFAs) with lipases from Pseudomonas fluorescens HU380 (HU-lipase), P. fluorescens AK102 (AK-lipase), and Candida rugosa (CR-lipase) were studied. The acidolysis of triolein with eicosapentaenoic acid (EPA) or docosahexaenoic acid (DHA) in n-hexane was evaluated with lipases immobilized on Celite 545. HU-lipase showed the highest incorporation rate at a low temperature (10 degrees C) with either EPA or DHA as the acyl donor, and the rate decreased with increasing reaction temperature. At 45 degrees C, the rates for EPA and DHA were 7.1 and 0.5 relative to those at 10 degrees C, respectively. The EPA incorporation rate was even higher at a low temperature (10 degrees C), and the DHA incorporation rate increased with decreasing temperature. Although AK-lipase showed the reverse tendency for incorporation rate, the DHA incorporation rate increased with increasing reaction temperature with both PUFAs. HU-lipase reacted well with PUFAs such as DHA, EPA, arachidonic acid (AA), mead acid (MA), and dihomo-gamma-linolenic acid (DGLA) on acidolysis and glyceride synthesis. The reactivities of AK-lipase toward these PUFAs except for DGLA, i.e., MA, AA, EPA, and DHA, were low for both reactions. The unique substrate specificities of the lipases from the Pseudomonas strains will enable us to use these lipases for the modification of fats and oils containing PUFAs such as fish oil.  相似文献   
139.
A novel electrolyte system having well structurally controlled aliphatic oligoether dendrons with a carbonate core is developed for lithium ion batteries. The synthetic dendrons have high boiling point, much higher dielectric constant up to 7.4–8.7 and better stability against oxidation than the conventional linear carbonates such as DEC. The ionic conductivities of the electrolyte with 80 wt% of dendrons and 20 wt% of LiTFSI are 0.11–0.61 mS cm−1 at 20 °C. A 463443-type prismatic battery having the electrolyte solution with 20 wt% dendrons was prepared and its battery performance such as capacity and cycleability was investigated. The prismatic battery with dendron-based electrolyte has the same level of capacity to that with the conventional carbonate-based electrolyte, and shows good cycleability, suggesting a high possibility to use as a kind of cosolvents for lithium ion batteries.  相似文献   
140.
A new catalytic system, which consists of Pd(OAc)2 as the catalyst and W–Mo-containing heteropolyacids (HPAs)/Mn(OAc)2 as the bicomponent cocatalysts, has been found to be very efficient in the oxidative carbonylation of phenol to diphenyl carbonate at low pressure in the absence of solvent. The efficiency of the catalytic system is dependent on the ratio of W/Mo in the HPAs, being best in a ratio of 6/6. The synergistic effect between W–Mo-containing HPAs and Mn(OAc)2 has been observed in the catalysis. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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