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1.
JAMES E. SIMON AMOTS HETZRONI BRUCE BORDELON GAINES E. MILES DENYS J. CHARLES 《Journal of food science》1996,61(5):967-970
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
2.
Lactic Acid Concentration and Microbial Spoilage in Anaerobically and Aerobically Stored Ground Beef 总被引:2,自引:0,他引:2
PATRICIA S. NASSOS A. DOUGLAS KING JR. ALLAN E. STAFFORD 《Journal of food science》1985,50(3):710-712
Lactic acid concentration of coarsely ground beef, packaged in low oxygen permeability casings, is inversely related to sensory acceptability of the meat following regrinding and aerobic storage for six additional days. Samples, reground and stored aerobically after periods of anaerobic storage, were assayed for total aerobic bacterial counts, percentage of gram-positive microflora, and pH. Lactic acid concentration ranged from 130 to 1055 mg per 100g ground beef and increased with anaerobic storage. During 6 days of aerobic storage, both increases and decreases in concentration were noted and related to changes in microbial flora. A positive correlation was found between the proportion of gram-positive bacteria (lactic acid bacteria) and lactic acid and pH. 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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BRUCE KING YIN LIU SURESH BASKARAN RICHARD LAINE JOHN HALLORAN 《Particulate Science and Technology》2013,31(3-4):121-132
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
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A key element of manufacturing planning and control involves the inter-functional coordination of various manufacturing requirements. This paper reports the results of a simulation experiment that compares alternative master production scheduling (MPS) procedures in an assemble-to-order environment. The MPS procedures are superbills and covering sets. For a given investment in safety stocks the managerial problem is how to construct the MPS in order to minimize the firm's delivery time pressures. The results of the simulation experiment strongly support the use of the superbill techniques over the covering set technique. Moreover, of the experimental factors that influence delivery time performance, the choice of master production scheduling technique has the largest effect. Demand variability has the next greatest effect on delivery time performance. The safely stock level has the third greatest effect and product commonality was fourth. Finally, the managerial implications of the results are discussed in detail. 相似文献
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By R. E. KING 《International journal of control》2013,86(2):191-200
The paper describes a numerical method using time-domain arrays for the analysis of discrete-continuous systems involving amplitude quantization, i.e. coded non-linearities. By the concept of generating matrices, systems of any order with synchronous or multi-rate samplers and involving multiple non-linearities may be analysed. The technique is particularly suited to digital computer implementation. An example of a saturating control system with error-amplitude quantization is considered. 相似文献
10.
P. CLAUDY J.M. LETOFFE G.N. KING J.P. PLANCHE B. BRULE 《Petroleum Science and Technology》2013,31(1):71-92
ABSTRACT Differential Scanning Calorimetry (D.S.C.) has been used to characterize the thermal behavior of various paving asphalts and their chromatographic fractions. In a single determination, several parameters, such as the glass transition temperature of the hydrocarbon matrix and the crystallized fractions, may be determined with good reproducibility. The glass transition is attributed to the aromatic and one part of the saturated fractions. The rest of the satured fraction has been found responsible for the endoihermal effect observed on warming which corresponds to the dissolution into the matrix. A method of determination of the crystallized fractions is described, and a comparison with the L.C.P.C. (Laboratoire Central des Ponts et Chaussdes - French Highway Administration Laboratory) method is made. The L.C.P.C. method was found to underestimate the real percentage of the crystallized fractions. 相似文献