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491.
Plastic mini‐chambers were used as tiny ‘glass houses’ to increase bud temperature in the vineyard. Open containers, with holes cut in them for ventilation, were used as controls, and inflorescences produced in those chambers were compared with inflorescences from modified chambers where either shade cloth or reflective foil were used to alter internal levels of photosynthetically‐active radiation (PAR) as well as temperature. Buds were treated for either14 days prior to budburst or for 13 days subsequent to budburst. Temperature and PAR were monitored immediately adjacent to the buds. Applied prior to budburst, the closed mini‐chambers increased bud temperatures and reduced flower numbers per inflorescence. Both ‘clear’ and ‘reflective foil’ treatments resulted in similar flower numbers. However, the shading treatment increased flower numbers by approximately 13%. Prior to budburst, there was a significant but weak correlation between average temperature and flower number per inflorescence for both the basal and apical inflorescence. Average PAR was not significantly correlated with flower number on either inflorescence, and did not improve the correlation when included with temperature in a multiple linear regression. Subsequent to budburst, flower numbers per inflorescence were decreased by the closed container but were unaffected by either the shading or foil treatment. The correlation between temperature and flower number on the apical inflorescence was maintained but the correlation between temperature and flower number on the basal inflorescence was no longer apparent. These results suggest that temperatures encountered in a vineyard during budburst can influence the number of flowers per inflorescence to the extent of a 15 to 25% variation in flower number. PAR, apart from influencing bud temperature, does not appear to influence flower number. The effect of temperature on flower differentiation diminishes as budburst advances.  相似文献   
492.
Predatory bacteria of the genus Bdellovibrio that prey upon Escherichia coli O157:H7 and Salmonella species were isolated from soil and sewage samples. Bdellovibrio isolates 45k (from soil) and 88e (from sewage) attacked and lysed the E. coli and Salmonella strains tested, with log10 reductions ranging from 2.5 to 7.9 CFU/mL after 7h incubation, using a two-membered culture system. The predators showed activity against the bacteria within the temperature range of 19 to 37C. Bdellovibrio isolate 45k reduced a population of E. coli dried on stainless steel surfaces by 3.6 log10 CFU/cm2 following 24 h contact time and at a 10:1 predator to prey ratio and was also effective in reducing the level of biofilm cells. Bdellovibrios can potentially be utilized for removal of bacteria from surfaces of food processing equipment and possibly for controlling the growth of pathogenic and spoilage bacteria in foods.  相似文献   
493.
Modelling the deep-fat frying of beef meatballs   总被引:1,自引:0,他引:1  
Mathematical models describing heat, moisture and fat transfers during deep-fat frying of beef meatballs were developed and validated against experimental data consisting of temperatures at two locations in the product, and average moisture and fat contents. Fat diffusivity in the product was 0.287 × 10-7m2s-1 while fat conductivity followed Eyring's model with frequency factor of 0.137 × 10-6m s-1 K-1 and activation energy of 2.70 kJ mol-1.  相似文献   
494.
This study was conducted over three seasons on irrigated Shiraz grapevines growing in a warm climate. We addressed the question of whether differences in berry size (within a population of berries from minimally pruned, own‐rooted or Ramsey‐grafted vines), would lead to differences in juice composition, wine composition or wine sensory score. Predictably, berry mass was found to increase with seed number, but berries in the smallest mass categories (0.3–0.7 g) still had similar juice soluble solids and pH; and similar concentrations of K+, tartaric acid and malic acid, compared with larger berries (1.4–2.0 g). Only for the very smallest mass category (0.3–0.55 g) was there any indication of better colour density (both for own‐rooted and Ramsey‐grafted vines) or higher anthocyanin concentration (for own‐rooted vines) compared with larger berries (1.4–2.0 g). Concentrations of tartaric acid and K+ in berry skins were highest in the smallest berry mass categories (0.3–0.7 g) and decreased with increasing berry mass (up to 1.4–2.0 g). A strong correlation (R2= 0.85) between skin tartaric acid and K+ concentrations was observed across that range. Small‐scale wine lots based on small berries (0.8–0.9 g) versus large berries (1.2–1.3 g) showed no differences in measures such as soluble solids, total acids or pH of juice; nor any differences in pH, total acids, K+, tartrate, malate, spectral characteristics or sensory score of corresponding wines. Moreover, small berries had a similar skin to fruit ratio, and a similar juice yield, compared to large berries. However, when measured post‐fermentation, the ratio of seed weight to skin weight was higher for small berries. The mass range of berries used here for small‐scale winemaking (i.e. from 0.8–0.9 g up to 1.2–1.3 g), covered the range of Shiraz berry mass typically found in irrigated vineyards (from 0.8 to 1.5 g), and thus confirms the relevance of present outcomes to practical winemaking. Finally, our data for variation in juice and wine composition as a function of berry size, showed consistent trends for all seasons, and thus implies that reported instances of improved wine quality from small berries (often associated with certain pruning treatments or deficit irrigation strategies), are more likely due to treatment effects that lead to small fruit, rather than to intrinsic developmental differences between large and small berries.  相似文献   
495.
Characterization of Starch and Fiber of Banana Fruit   总被引:2,自引:0,他引:2  
Mature green and ripe bananas were analyzed for moisture, protein, starch, sugars, ash, and fiber. Ripe banana fruit contained 1.27% dietary fiber, as determined by the detergent method. Hemicellulose content was higher than that of most fruits and vegetables whereas cellulose and lignin contents were lower. The morphological and physicochemical properties of isolated starch were determined. Starch granules were irregularly shaped, with spheroid and elongated forms predominating. Both the Brabender amylograms and the two-stage swelling patterns of the starch were similar to those reported for mung bean starch.  相似文献   
496.
Six paired beef round and pork loin roasts were used to determine the effects of sodium tripolyphosphate (STPP) on fresh and reheated roasts. Roasts were pumped 10% of their weight with distilled water (control) or with distilled water containing 4.75% STPP. Roasts were cooked to internal temperatures of 70°C (beef) or 75°C (pork) and evaluated after 0, 1 or 3 days (roasts were reheated to cooked temperatures). This study indicates that phosphate in pork and beef roasts allowed them to be reheated after 1 and 3 days of refrigeration with minimal losses of juiciness, tenderness or flavor intensity, Phosphate injection reduced warmed-over flavor in reheated pork roasts but was not successful in decreasing the incidence of warmedover flavors in reheated beef roasts.  相似文献   
497.
Competitive adsorption between glycerol monostearate (GMS) and whey protein isolate (WPI) or sodium caseinate was studied in oil-in-water emulsions (20 wt % soya oil, deionized water, pH 7). Addition of GMS resulted in partial displacement of WPI or sodium caseinate from the emulsion interface. SDS-PAGE showed that GMS altered the adsorbed layer composition in sodium caseinate stabilized emulsions containing < 1.0 wt % protein. Predominance of β-casein at the interface in the absence of surfactant was reduced in the presence of GMS. The distribution of α-lactalbumin and β-lactoglobulin between the aqueous bulk phase and the fat surface in emulsions stabilized with WPI was independent of the concentration of added protein or surfactant.  相似文献   
498.
The effect of pendulum inertia on Pea Tenderometer readings was examined by recording the pendulum angle and the torque that it applies to the peas during a test. The effect was significant at the critical point in the test cycle where the torque is at a maximum. It was concluded that this affects the standardization of the Tenderometer.  相似文献   
499.
This article reports an experiment in world city network analysis focusing on city‐dyads. Results are derived from an unusual principal components analysis of 27,966 city‐dyads across 5 advanced producer service sectors. A 2‐component solution is found that identifies different forms of globalization: extensive and intensive. The latter is characterized by very high component scores and describes the more important city‐dyads focused upon London‐New York (NYLON). The extensive globalization component heavily features London and New York but with each linked to less important cities. U.S. cities score relatively high on the intensive globalization component and we use this finding to explain the low connectivities of U.S. cities in previous studies of the world city network. The two components are tentatively interpreted in world‐systems terms: intensive globalization is the process of core‐making through city‐dyads; extensive globalization is the process of linking core with non‐core through city‐dyads.  相似文献   
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