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排序方式: 共有439条查询结果,搜索用时 15 毫秒
11.
PETER TAYLOR ALLAN B. CAMPBELL DERREK G. OWEN 《Journal of the American Ceramic Society》1983,66(5):347-351
The limits of miscibility at 650°C were determined for compositions with the mole ratio SiO2 /B2 O3 =1.07 in the systems X2 O-MO-B2 O3 -SiO2 (X = Na,K; M = Mg,Ca,Ba) and Na2 O-MgO-BaO-B2 O3 -SiO2 . The form of the miscibility gaps in the quaternary systems is similar to that previously described for the system Na2 O-ZnO-B2 O3 -SiO2 . The topography of miscibility gaps in systems of this type is discussed in detail. The extent of the miscibility gap is correlated with the polarizing power of each cation, X and M (Na > K and Zn ≅ Mg > Ca > Ba) both among the seven quaternary systems and within the single five-component system examined. The possibility of using empirical correlations observed among the quaternary systems to predict the behavior of other compositions, or of more complex systems, is explored. 相似文献
12.
HELEN A. GRUBER PAUL L. KRONICK PETER R. BUECHLER MARY V. HANNIGAN 《Journal of food science》1990,55(6):1506-1509
Collagen, elastin and residual actomyosin in connective tissue of some lower grades of beef were determined from the contents of hydroxy-proline, valine and glutamic acid, using three simultaneous equations based on amounts of these amino acids found in the pure proteins. The complete amino-acid profiles of the connective tissues agreed with the calculated protein compositions. Connective tissues were removed from the meat by dissection, and sequential saline extractions removed sarcoplasmic and myofibrillar proteins. Glycoproteins were removed by extraction with half-saturated calcium hydroxide; collagen, by autoclaving. Changes in composition after extraction or au-toclaving were confirmed by histological investigations. 相似文献
13.
Competitive Adsorption Between Sodium Caseinate and Oil-Soluble and Water-Soluble Surfactants in Oil-in-Water Emulsions 总被引:2,自引:0,他引:2
SUSAN E. EUSTON HARJINDER SINGH PETER A. MUNRO DOUGLAS G. DALGLEISH 《Journal of food science》1995,60(5):1124-1131
Competitive adsorption between sodium caseinate and either a water-soluble surfactant, Tween 60 (polyoxyethylene sorbitan monostearate—PSM) or an oil-soluble surfactant, Span 60 (sorbitan monostearate—SM) was studied in oil-in-water emulsions. Surfactants were present during homogenization. Surface concentration of protein in freshly prepared emulsions decreased as concentration of PSM or SM increased. However, only partial displacement of protein was observed with either surfactant. The reduction in protein surface concentration was greater in the presence of PSM. Interfacial protein composition was independent of surfactant type. In the absence of surfactant, preferential adsorption of β-casein occured in emulsions containing ≤1.0 wt % protein. On addition of surfactant preference for β-casein at the interface was reduced. 相似文献
14.
BASSAM A. ANNOUS ETHAN B. SOLOMON PETER H. COOKE ANGELA BURKE 《Journal of Food Safety》2005,25(4):276-287
The ability of two strains of Salmonella to form biofilms on whole cantaloupe melons was investigated. Ten microliters of bacterial suspensions was spot‐inoculated onto cantaloupe melon rinds in pre‐marked areas, and the cantaloupe melons were held at either 10 or 20C. Biofilm formation was monitored using scanning electron microscopy on excised portions of the cantaloupe melon rind at 2, 24, 48, 72 and 144 h postinoculation. Micrographs indicated that biofilm formation occurred rapidly following introduction of cells (2 h at 20C) onto the cantaloupe melon rind. A fibrillar material was visible after just 2 h at 20C, and cells were embedded in extracellular polymeric material after 24 h at either temperature. These results indicate that a human pathogen is capable of forming a biofilm on plant tissue and that biofilm formation may be responsible for the increased recalcitrance of bacteria to aqueous sanitizers. 相似文献
15.
PETER J. BECHTEL 《Journal of Food Processing and Preservation》2003,27(2):101-116
Individual fish processing waste stream components can be used to make feed ingredients or other products. Waste stream components obtained from commercial fish processing plants included heads, viscera, frames, and skins from Alaska pollock (Theragra chalcogramma) and Pacific cod (Gadus macrocephalus); and heads, and viscera from pink salmon (Oncorhynchus gorbuscha). The protein content of heads from all three species ranged from 13.9 to 16.4%; and the fat content ranged from 0.9 to 10.9%. Viscera protein content ranged from 13.0 to 15.3%, and the fat content from 2.0 to 19.1%. After heating to 85C the percent soluble protein in salmon heads was different (P < 0.05) from pollock or cod heads. Percent soluble protein of pollock and cod skin increased 8fold (P<0.05) after the 85C heat treatment. Connective tissue content was calculated from chemical determination of hydroxyproline content, and large differences in percent connective tissue content were found (1% for pollock viscera to 46% for skin). Estimated rat PER values ranged from a low of 2.1 for skin to a high of 3.1 for viscera and fillet samples (P<0.05). 相似文献
16.
KARL J. SOMMER MUHAMMAD T. ISLAM PETER R. CLINGELEFFER 《Australian Journal of Grape and Wine Research》2000,6(2):99-108
Fruit bud initiation in Sultana is more sensitive to climatic factors than fruit bud initiation in other cultivars. This paper considers historical findings regarding the influence of light and temperature on fruit bud initiation and fruitfulness in view of modern Sultana vineyard management practices.
Past results were reviewed and confirmed by experiments in which variability in vine size and structure was introduced by grafting and modifications of trellis design. Ramsey-grafted vines were consistently less fruitful than own-rooted Sultana, possibly because of a more shaded canopy interior due to greater vegetative growth of vines grafted to Ramsey rootstock. Carbohydrate reserves of node and internode tissue in late winter between node 2 and 18 followed a similar trend along the cane as fruitfulness in the following spring. 相似文献
Past results were reviewed and confirmed by experiments in which variability in vine size and structure was introduced by grafting and modifications of trellis design. Ramsey-grafted vines were consistently less fruitful than own-rooted Sultana, possibly because of a more shaded canopy interior due to greater vegetative growth of vines grafted to Ramsey rootstock. Carbohydrate reserves of node and internode tissue in late winter between node 2 and 18 followed a similar trend along the cane as fruitfulness in the following spring. 相似文献
17.
The effect of Saccharomyces bayanus-mediated fermentation on the chemical composition and aroma profile of Chardonnay wine 总被引:1,自引:0,他引:1
18.
Hall effect sensors were used to determine residence time distributions for diced carrot particles in 4% Colflo 67 carrier fluid. Four sensors at either end of a 3.2 m long 2 in. IDF tube viscometer allowed residence times to be measured for carrot particles incorporating a ceramic magnet. Mean particle residence times were greater than mean bulk residence time for 8 mm diced carrots, whereas 15 mm carrots showed trials in which particles travelled faster than the bulk fluid. Increasing concentration of 15 mm diced carrots from 3.25, 6.30, 9.16 to 11.85% w/w resulted in decreasing mean particle residence times from 17.6, 17.0, 15.9 to 14.3 s, with minimum residence times of 16.4, 16.2, 14.8 and 13.4 s, respectively. This sensing technique operates through stainless steel, providing applications for UHT foods containing particles. In addition, the technique was not affected by high particle concentration, and will operate for any distribution of particle size, shape or type. 相似文献
19.
A phenomenological approach was developed for conversion of coal to pyridine soluble materials with the object of shedding additional light on the reactions taking place during short contact times. The approach was based on a theoretical analysis of many parallel reactions in a complex reacting mixture. The analysis used the concept of lumped species and weighted activation energies to improve on coal liquefaction models. i.e. to remove insensitivity problems for parameters in coal liquefaction models and to answer questions about behaviour of liquefaction reactions in different vessels. 相似文献
20.
ANTENNAL AND BEHAVIORAL RESPONSES OF GRAPEVINE MOTH <Emphasis Type="Italic">Lobesia botrana</Emphasis> FEMALES TO VOLATILES FROM GRAPEVINE 总被引:2,自引:0,他引:2
Tasin M Anfora G Ioriatti C Carlin S De Cristofaro A Schmidt S Bengtsson M Versini G Witzgall P 《Journal of chemical ecology》2005,31(1):77-87
Grapevine moth Lobesia botrana is the economically most important insect of grapevine Vitis vinifera in Europe. Flower buds, flowers, and green berries of Chardonnay grapevine are known to attract L. botrana for oviposition. The volatile compounds collected from these phenological stages were studied by gas chromatography—mass spectrometry, and the antennal response of L. botrana females to these headspace collections was recorded by gas chromatography—electroantennography. The compounds found in all phenological stages, which consistently elicited a strong antennal response, were pentadecane, nonanal, and -farnesene. In a wind tunnel, gravid L. botrana females flew upwind to green grapes, as well as to headspace collections from these berries released by a piezoelectric sprayer release device. However, no females landed at the source of headspace volatiles, possibly due to inappropriate concentrations or biased ratios of compounds in the headspace extracts. 相似文献