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971.
Interest in babies was assessed in 32 8–9 yr olds and 32 14–15 yr olds by 6-sec time sampling of waiting room behaviors in the presence of a live baby and by reactions to pictures of babies vs other objects. Age conferred mode differences in behavioral responsivity: Adolescents made more proximal bids, 8–9 yr olds more distal bids. Males and females differed in amount of behavioral and perceptual baby interest, with girls more responsive than boys. Sex differences were virtually absent among 8–9 yr olds but emerged during adolescence. Interpretations in terms of increased salience of sex-role stereotypes during adolescence are offered. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
972.
This is the first report to identify the presence of chicoric acid (cichoric acid; also known as dicaffeoyltartaric acid, which is a caffeic acid derivatized with tartaric acid) in basil leaves. Rosmarinic acid, chicoric acid and caftaric acid (in the order of most abundant to least; all derivatives of caffeic acid) were identified in fresh basil leaves. Rosmarinic acid was the main phenolic compound found in both leaves and stems. Chicoric acid was not detected in sweet basil stems, although a small amount was present in Thai basil stems. Other cinnamic acid monomers, dimers and trimers were also found in minor quantities in both stems and leaves. Basil polyphenolic contents were determined by blanched methanol extraction, followed by HPLC/DAD analysis. The characterization of the polyphenolics found in the basil extracts were performed by HPLC/DAD/ESI–MS/MS and co-chromatographed with purchased standard. The influence of inoculation with an arbuscular mycorrhizal fungus (AMF), Glomus intraradices, on plant phenolic composition was studied on two basil cultivars,‘Genovese Italian’ and ‘Purple Petra’. Inoculation with AMF increased total anthocyanin concentration of ‘Purple Petra’ but did not alter polyphenolic content or profile of leaves and stems, of either cultivar, compared to non-inoculated plants. In the US diet, basil presents a more accessible source of chicoric acid than does Echinacea purpurea, in which it is the major phenolic compound.  相似文献   
973.
The objective of this study was to assess the influence of the interaction among alcohol, tannins, and mannoproteins on the aroma, flavor, taste, and mouthfeel characteristics of selected commercial Merlot wines. Merlot wines (n = 61) were characterized for wine chemistry parameters, including pH, titratable acidity, alcohol, glucose, fructose, tannin profile, total proteins, and mannoprotein content. Agglomerative clustering of these physicochemical characteristics revealed 6 groups of wines. Two wines were selected from each group (n = 12) and profiled by a trained sensory evaluation panel. One wine from each group was evaluated using the electronic tongue (e‐tongue). Sensory evaluation results showed complex effects among tannins, alcohol, and mannoproteins on the perception of most aromas, flavors, tastes, and mouthfeel attributes (P < 0.05). The e‐tongue showed distinct differences among the taste attributes of the 6 groups of wines as indicated by a high discrimination index (DI = 95). Strong correlations (r2 > 0.930) were reported between the e‐tongue and sensory perception of sweet, sour, bitter, burning, astringent, and metallic. This study showed that interactions among wine matrix components influence the resulting sensory perceptions. The strong correlation between the e‐tongue and trained panel evaluations indicated the e‐tongue can complement sensory evaluations to improve wine quality assessment.  相似文献   
974.
Wheat represents a ubiquitous commodity and although industries valorize 10% of wheat bran, most of this antioxidant‐rich byproduct gets fed to livestock. The objective of this study was to incorporate wheat bran into an extruded snack. Bran samples from hard red spring, soft white club cv. Bruehl, and purple wheat lines were added to cv. Waxy‐Pen wheat flour (Triticum aestivum L.) at replacement concentrations of 0%, 12.5%, 25%, and 37.5% (w/w; n = 10). Extrudates were evaluated for antioxidant capacity, color, and physical properties. Results showed that high fiber concentrations altered several pasting properties, reduced expansion ratios (P < 0.0001), and created denser products (P < 0.0001), especially for white bran supplemented extrudates. Purple bran supplemented extrudates produced harder products compared to white and red bran treatments (P < 0.0001). Extrudates produced with 37.5% (w/w) of each bran variety absorbed more water than the control with no added bran. The oxygen radical absorption capacity assay, expressed as Trolox Equivalents, showed that extrudates made with addition of red (37.5%) and purple (37.5%) bran had higher values compared to the other treatments; the control, red, and white bran treatments had less antioxidant activity after extrusion (P < 0.0001) compared to purple bran supplemented extrudates. Purple and red brans may serve as viable functional ingredients in extruded foods given their higher antioxidant activities. Future studies could evaluate how bran variety and concentration, extruded shape, and flavor influence consumer acceptance.  相似文献   
975.
A national quantitative survey of Campylobacter jejuni and Campylobacter coli in 1,011 uncooked retail meat samples (beef, unweaned veal, chicken, lamb and mutton, and pork) was undertaken from August 2003 to June 2004 to establish baseline proportionality data. The presence, number, and type of Campylobacter present in each sample was assessed. Prevalences of C. jejuni and C. coli were 89.1% in chicken, 9.1% in pork, 6.9% in lamb and mutton, 3.5% in beef, and 10% in unweaned veal. C. jejuni was identified in the majority of positive samples (246 of 259). In chicken samples positive for C. jejuni, 40.2% had counts of <0.3 most probable number (MPN)/g, 50.5% had 0.3 to 10.0 MPN/g, 8.8% had 10.1 to 50.0 MPN/g, and 0.5% had 110 MPN/g. In other meats (49 samples), Campylobacter counts were < or = 0.3 MPN/g, except for one unweaned veal sample at > 10.9 MPN/g. Penner serotyping and SmaI macrorestriction genotyping using pulsed-field gel electrophoresis with 247 isolates revealed 17 Penner serotypes and 56 electrophoresis profiles. Seven Penner serotypes (HS1 complex, 2, 4 complex, 6, 11, 27, and 42) were represented by 10 or more isolates from chicken. When data from both typing methods were combined, 62 sero-genotypes were generated. In a comparison of these sero-genotypes with historical data for isolates from human cases, 71% of the beef isolates, 50% of the lamb and mutton isolates, 50% of the pork isolates, 41% of the chicken isolates, and 25% of the unweaned veal isolates were common to both sources. These results provide baseline proportionality profiles of Campylobacter in these five meats and will facilitate exposure assessment in combination with other information such as consumption data and subsequent quantitative risk assessment.  相似文献   
976.
Ozone formation is a complex function of local hydrocarbon and nitrogen oxide emissions. Therefore, trading of NOx emissions among geographically distributed facilities can lead to more or less ozone formation than across-the-board reductions. Monte Carlo simulations of trading scenarios involving 51 large NOx point sources in eastern Texas were used in a previous study by the authors to assess the effects of trading on air quality benefits, as measured by changes in ozone concentrations. The results indicated that 12% of trading scenarios would lead to greater than a 25% variation from conventional across-the-board reductions when air quality benefits are based only on changes in ozone concentration. The current study found that when benefits are based on a metric related to population exposure to ozone, two-thirds of the trading scenarios lead to changes in air quality benefits of approximately 25%. Variability in air quality benefits is not as strongly dependent on the temporal distribution of NOx emissions.  相似文献   
977.
978.
Examined 2 crucial variables which might explain inconsistent results of attempts to condition vocalization in the rat: mobility of the S during conditioning and variability of the intertrial interval (ITI). 12 male Long-Evans rats were tested in 4 conditions of mobility-immobility, and fixed and variable ITI. Results support the importance of immobilizing the S, but not of varying the ITI during conditioning. It is suggested that vocal behavior in the rat may be conditioned only when no competing species-specific defense reaction (e.g., freezing) is available to the S. (31 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
979.
NASA is investigating the use of advanced automation to enhance crew productivity for Space Station Freedom in numerous areas, one being failure management. This paper describes a prototype that diagnoses failure sources and assesses the future impacts of those failures on other Freedom entities.  相似文献   
980.
A rapid method for determining total S in plants by X-ray fluorescence spectro-metric analysis of ground pelletised plant material is compared with chemical methods using titrimetric, flame photometric and turbidimetric methods of sulphate determination. Errors in the chemical methods were caused by incomplete oxidation of organic sulphur and by non-reproducibility of the turbidimetric determination of sulphate. A method incorporating the oxidation of the sample with HNO3 and Mg(NO3)2 and titration of the reduced sulphate by mercuric acetate gave recoveries accurate to a mean of 1% when determining the sulphur content of sulphur compounds. Taking the results for plant materials determined by the titrimetric method as standard, XRF gave sulphur values with a mean difference of 4%; the flame photometric determination of sulphate after HNO3 + Mg(NO3)2 oxidation gave results with a mean difference of 12%. The effect of absorption of S radiation by silicon is noted.  相似文献   
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