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171.
A geodatabase of tidal constituents is developed to present the regional assessment of tidal stream power resource in the USA. Tidal currents are numerically modeled with the Regional Ocean Modeling System (ROMS) and calibrated with the available measurements of tidal current speeds and water level surfaces. The performance of the numerical model in predicting the tidal currents and water levels is assessed by an independent validation. The geodatabase is published on a public domain via a spatial database engine with interactive tools to select, query and download the data. Regions with the maximum average kinetic power density exceeding 500 W/m2 (corresponding to a current speed of ~1 m/s), total surface area larger than 0.5 km2 and depth greater than 5 m are defined as hotspots and documented. The regional assessment indicates that the state of Alaska (AK) has the largest number of locations with considerably high kinetic power density, followed by, Maine (ME), Washington (WA), Oregon (OR), California (CA), New Hampshire (NH), Massachusetts (MA), New York (NY), New Jersey (NJ), North and South Carolina (NC, SC), Georgia (GA), and Florida (FL).  相似文献   
172.
The primary objective of the study was to quantify the effect of stocking rate (SR) and calving date (CD) on milk production, dry matter intake (DMI), energy balance (EB), and milk production efficiency over 4 consecutive years (2009 to 2012). Two groups of Holstein-Friesian dairy cows with different mean CD were established from within the existing research herd at Moorepark (Teagasc, Ireland). Animals were assigned to either an early calving (mean CD February 14) treatment or a late calving (mean CD March 2) treatment. Animals within each CD treatment were randomly allocated to 1 of 3 whole-farm SR treatments: low (LSR; 2.51 cows/ha), medium (MSR; 2.92 cows/ha), and high (HSR; 3.28 cows/ha), and animals remained on the same farmlet for the duration of the study. Individual animal DMI was estimated 3 times per year at grass using the n-alkane technique in March (spring), May (summer), and September (autumn), corresponding to, on average, 45, 132, and 258 d in milk, respectively. A total of 138 spring-calving dairy cows were used during each year of the study. The effects of SR, CD, season, and their interaction were studied using mixed models. Individual animal milk production, body weight, body condition score, and the efficiency of milk production were significantly decreased as SR increased due to a reduction in herbage availability. The existence of CD × SR × season interactions for production, DMI, and EB indicate that delaying the herd mean CD can be an effective strategy to minimize the reduction in animal performance, particularly in spring at higher SR. This study further confirms the benefits of a new approach to the evaluation of herbage allowance known as the individual herbage allowance, which encompasses the 3 main factors restricting DMI in rotational grazing; namely, the average daily herbage allowance of the group, the intake capacity of the individual animal within the group, and the relative intake capacity of the animal within the competing herd.  相似文献   
173.
L-lactic acid is an important organic acid widely used in pharmaceutical, food and textile industries. Bacillus coagulans BCS13002 can efficiently produce L-lactic acid with two kinds of carbon sources. BCS13002 produced L-lactic acid at a content of 10.23 ± 0.16 g/L and 11.67 ± 0.22 g/L, when glucose and gelatinised and hydrolysed corn starch (GHCS) were used, respectively. GHCS exhibits several advantages, including high yield of L-lactic acid and low cost. Proteomics analyses identified several key enzymes, which contributed to the higher production of L-lactic acid when GHCS was used as the carbon source. Those key enzymes were involved in the two-component system (SpoOF), pantothenate and CoA biosynthesis (pantothenate synthetase, 1.584-fold; dihydroxy-acid dehydratase, 1.517-fold), beta-alanine metabolism (1.605-fold) and valine, leucine and isoleucine biosynthesis (1.517-fold) pathways. This study provides a biological basis for using GHCS as a substitute of glucose in the production of L-lactic acid.  相似文献   
174.
Reducing food waste is a priority to move towards more sustainable food systems. Since agro-food by-products are often rich in healthy compounds, such as fibre, phytochemicals, protein, fatty acids, vitamins and minerals, the waste valorisation could move through their transformation into ingredients useful for the formulation of functional foods. Pasta is a staple food widely consumed all over the world representing an optimal carrier for nutrients delivery. The incorporation of ingredients of a high added value obtained by agro-industrial by-products in pasta can improve its nutritional value and provides several health benefits. At the same time, the inclusion of new ingredients could modify the physical, chemical and textural properties determining the change of the organoleptic characteristics of fortified pasta, affecting its acceptability. Thus, the preparation of new pasta formulations with high nutritional properties, good technological and sensory characteristics represents a challenge for the food industry.  相似文献   
175.
We characterised the formation and dynamic changes in the main aroma compounds produced during the manufacturing process of Jinxuan and Qingxin oolong tea. Thirty-five aroma compounds were investigated. Subsequent principal component and cluster analyses showed that the fresh leaves, spread leaves and rocked leaves of the two varieties of tea were distinguished from each other. Particularly, the aldehyde and ‘other’ compounds showed the highest correlation coefficients (0.71 and −0.70) among the principal. The heat map showed that the proportions of acetic acid, 3-methylbutanal and 2-methylbutanal significantly changed during the manufacturing process of the two tea varieties. The key amino acids (isoleucine, leucine, valine and aspartic acid) and enzymes (branched-chain amino acid aminotransferase, aspartate aminotransferase and acetaldehyde dehydrogenase) involved in the synthesis of 3-methylbutanal and 2-methylbutanal differed between the two varieties during manufacture. Our study reveals the characteristics of different varieties of oolong tea and their aroma formation after manufacture using the same process.  相似文献   
176.
Phenolic compounds have been shown to deliver numerous health benefits. Research has also shown that starch and phenolic compounds interact. This study aimed to investigate the effects of blackcurrant and strawberry powder on the physicochemical and in vitro predicted glycaemic response of sweet potato and potato starches. Sweet potato, or potato, starches were mixed with 0%, 5%, 10% and 15% (w/w) of blackcurrant, or strawberry, powder, to form blackcurrant and strawberry-enriched starch pastes. The results showed that enrichment with 5%, 10% and 15% blackcurrant or strawberry powder for sweet potato and potato starch significantly altered the pasting viscosity and colour profiles (P < 0.05), increased the phenolic content and antioxidant activities of starch pastes (P < 0.05). Blackcurrant or strawberry powders mixed with sweet potato or potato starches reduced amount of reducing sugar released during in vitro digestion. Addition of 15% blackcurrant powder for the starch exerted stronger in vitro antioxidant and hypoglycaemic properties than that of 15% strawberry powder. Collectively, these findings suggested that addition of blackcurrant or strawberry powder into sweet potato and potato starches manipulated the hypoglycaemic property of pastes.  相似文献   
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Fusel oils (FOs) are higher alcohols (including propanol, isobutanol, isoamylol, and active amyl alcohol), which affect the aroma profiles and flavor profiles of wine. A novel method for determination of FOs in lychee wine was developed using headspace gas chromatography (HS-GC). Results showed that 12% standard curve (SC) can be used to determinate the FOs of low alcoholic beverages, yet 40% SC can be used for high alcoholic beverages (e.g., brandy). Optimization of the parameters of equilibrium temperature at 50 °C was maintained for 30 min. The stabilized gas-liquid phase ratio of 3:1 for further research had no significant differences with others, which is caused by the distribution coefficient of K???100. The addition of sodium chloride (NaCl) decreased the partition coefficient of FOs markedly, and an inverse situation was observed for the extraction of FOs saturating at 1.25 g NaCl in 5 mL LW. Relative standard deviations (RSD) of reproducibility tests were in the range of 1.03–4.91%. Meanwhile, the mean recoveries of low, middle, and high concentration levels were 100.94, 103.2, and 96.74%, respectively. HS-GC was a stabilized, concise, and efficient method compared with the International Organization of Vine and Wine (OIV) method of OIV-MA-BS-14. These findings provide a foundation to determine higher alcohols of alcoholic beverages.  相似文献   
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