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1.
今天的便携应用越来越依赖于单节锂离子电池和锂聚合物电池提供电能.与镍氢电池(NiMH)相比,高能量密度的锂离子电池具有体积小、应用灵活、待机时间长等特性,非常适合便携系统应用.电池功率管理器STw4101的特点和应用.  相似文献   
2.
Electronic Sensing of Aromatic Volatiles for Quality Sorting of Blueberries   总被引:2,自引:0,他引:2  
An electronic sniffer using semi-conductor gas sensors that nondestructively measured aromatic volatile gas emissions from fruit was developed to assess blueberry quality. The sniffer detected soft and damaged fruit in packaged containers at a 5% level of damage and distinguished four of five fruit ripeness classes: (1) mature-green and green-pink; (2) blue-pink; (3) blue; and (4) ripe fruit. Sniffer response increased as fruit ripened, as did total concentration of aromatic volatiles. Sniffer response correlated with berry firmness, pH, titratable acidity, and color, and detected differences among 10 cultivars, as did impact response analysis. The electronic sniffer is rapid, nondestructive and may be used to sort and quality check for presence of unripe or damaged fruit in closed packs of fresh berries.  相似文献   
3.
This paper provides an empirical characterization of user actions at the web browser. The study is based on an analysis of 4 months of logged client-side data that describes user actions with recent versions of Netscape Navigator. In particular, the logged data allow us to determine the title, URL and time of each page visit, how often they visited each page, how long they spent at each page, the growth and content of bookmark collections, as well as a variety of other aspects of user interaction with the web. The results update and extend prior empirical characterizations of web use. Among the results we show that web page revisitation is a much more prevalent activity than previously reported (approximately 81% of pages have been previously visited by the user), that most pages are visited for a surprisingly short period of time, that users maintain large (and possibly overwhelming) bookmark collections, and that there is a marked lack of commonality in the pages visited by different users. These results have implications for a wide range of web-based tools including the interface features provided by web browsers, the design of caching proxy servers, and the design of efficient web sites.  相似文献   
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ABSTRACT

Yttrium aluminum garnet (YAG - Y3Al5O12) fibers have been prepared by dry spinning solutions of yttrium and aluminum carboxylate polymers (precursor route) and by dry spinning aqueous oxide sols (sol-gel route). Fibers from aqueous diphasic gels are prepared by mixing a colloidal alumina sol containing 50-nm hydrous alumina with a colloidal yttria sol containing 10-nm yttrium oxide, using polyvinylpyrrolidone as a spinning aid. Fibers by the precursor route are made from spinnable THF solutions of yttrium isobutyrate and aluminum isobutyrate or from aqueous solutions of polymeric aluminum formate and yttrium acetate.

The isobutyrate materials decompose between 200-400°C to an amorphous residue. Crystallization occurs abruptly between 875°C and 900°C, forming the YAG phase directly. The formate-acetate also decomposes to amorphous residues, which form YAG at 900°C. In the diphasic gel, YAG forms gradually between 1000 and 1200°C, with intermediate products YAP (YalO3 perovskite) and/or YAM (Y4Al2O9 monoclinic). At 1500°C, single phase YAG is obtained as pore-free fibers with 500 nm grains.  相似文献   
6.
D. L. HORTON (SEE 42:4) HAS ATTEMPTED TO REJECT B. EARHARD AND G. MANDLER'S (SEE 40:3) INTERPRETATION OF DATA FROM EXPERIMENTS WHERE "MEDIATION" HAS BEEN PRODUCED BY STANDARD PAIRED-ASSOCIATE PROCEDURES. IT IS ARGUED THAT (1) HORTON'S REVIEW OF UNLEARNING DATA IS INADEQUATE AND THAT EVIDENCE OF UNLEARNING IS PRESENT IN STUDIES HE CITES AS PROVIDING NO EVIDENCE OF UNLEARNING; (2) HIS EVALUATION OF THE INTERLIST INTERFERENCE INTERPRETATION OF DIFFERENCES BETWEEN EACH OF THE MEDIATED FACILITATION, MEDIATED INTERFERENCE, AND PSEUDOMEDIATION PARADIGMS, AND THE STANDARD CONTROL PARADIGM IS UNSATISFACTORY; AND (3) HIS CONTENTION THAT THE MOST ADEQUATE ACCOUNT OF AVAILABLE DATA IS PROVIDED BY MEDIATION THEORY IS ACHIEVED ONLY AT THE EXPENSE OF PASSING OVER A VERY SUBSTANTIAL BODY OF DATA INCOMPATIBLE WITH A MEDIATION INTERPRETATION OF PAIRED-ASSOCIATE PARADIGMS. (FRENCH SUMMARY) (30 REF.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
7.
The rheology of 10 Australian honeys was investigated at temperatures ?15C to 0C by a strain‐controlled rheometer. The honeys exhibited Newtonian behavior irrespective of the temperature, and follow the Cox–Merz rule. G″/G′ and ω are quadratically related, and the crossover frequencies for liquid to solid transformation and relaxation times were obtained. The composition of the honeys correlates well (r2 > 0.83) with the viscosity, and with 247 data sets (Australian and Greek honeys), the following equation was obtained: The viscosity of the honeys showed a strong dependence on temperature, and four models were examined to describe this. The models gave good fits (r 2 > 0.95), but better fits were obtained for the WLF model using Tg of the honeys and µg= 1011 Pa.s. The WLF model with its “universal values” poorly predicted the viscosity, and the implications of the measured rheological behaviors of the honeys in their processing and handling are discussed.  相似文献   
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The use of low-molecular-weight di-isocyanates to shrink-resist wool has been re-examined. If steam cured for long periods low application levels would shrink-resist wool, but, except for DDI, a di-isocyanate (mol. wt. 600) derived from dimerized C18 unsaturated fatty acids (General Mills), their use was impractical owing to the firm fabric handle or toxic vapours. The bisulphite adducts of low-molecular-weight di-isocyanates, apart from that of DDI, did not shrink-resist wool. The finish imparted by DDI or its bisulphite adducts had better stability to thermal-and photo-degradation than that with polyether polyisocyanates or their bisulphite adducts. The use of other ‘dimer acid’ derivatives to shrink-resist wool was also examined.  相似文献   
10.
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