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21.
The aim of this paper is to empirically test whether interlinking patterns between higher education institutions (HEIs) conform to a document model, where links are motivated by webpage content, or a social relationship model, where they are markers of underlying social relationships between HEIs. To this aim, we analyzed a sample of approximately 400 European HEIs, using the number of pages on their web domains and the total number of links sent and received; in addition we test whether these two characteristics are associated with organizational size, reputation, and the volume of teaching and research activities. Our main findings are as follows: first, the number of webpages of HEI websites is strongly associated with their size, and to a lesser extent, with the volume of their educational activities, research orientation, and reputation; differences between European countries are rather limited, supporting the insight that the academic Web has reached a mature stage. Second, the distribution of connectivity (as measured by the total degree of HEI’s) follows a lognormal distribution typical of social networks between organizations, while counts of weblinks can be predicted with good precision from organizational characteristics. HEIs with larger websites tend to send and receive more links, but the effect is rather limited and does not fundamentally modify the resulting network structure. We conclude that aggregated counts of weblinks between pairs of HEIs are not significantly affected by the web policies of HEIs and thus can be considered as reasonably robust measures. Furthermore, interlinking should be considered as proxies of social relationships between HEIs rather than as reputational measures of the content published on their websites. 相似文献
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Effect of sex-sorted sperm dosage on conception rates in Holstein heifers and lactating cows 总被引:1,自引:0,他引:1
DeJarnette JM Nebel RL Marshall CE Moreno JF McCleary CR Lenz RW 《Journal of dairy science》2008,91(5):1778-1785
Ejaculates were collected by artificial vagina from 3 Holstein sires and sorted to 90% purity for X-chromosome-bearing spermatozoa (range 88 to 93%) using flow cytometry. Sorted sperm were diluted to 2.1, 3.5, or 5.0 × 106 sperm per dose in an egg yolk (20%), Tris, glycerol (7%) extender. Collections were repeated until >600 straws per sperm dose per sire were obtained. Each sperm dose was loaded into color-coded 0.25-mL French straws, with alternate colors used to define treatments across sires. Within sires, straws were packaged at 9 per cane (3 of each color) and strategically allocated to 75 Holstein herds with targets for 50% use in heifers and 50% in lactating cows. Straw color was recorded in the on-farm record-keeping system at the time of insemination. Data were analyzed separately for cows and heifers. Among heifers, a total of 2,125 usable records were retrieved from 51 herds (238 ± 5.5 services/ sperm dose per sire, range: 218 to 263). Conception rates in heifers were influenced by the sire × sperm dosage interaction. Within sire A, conception rates of heifers were greater for the 5 × 106 (59.5%) than for the 2.1 × 106 (46.4%) sperm dose and intermediate for the 3.5 × 106 sperm dose (52.2%). However, across sires, sperm dosage had no effect on heifer conception rates (46.7, 51.2, and 52.5% for the 2.1, 3.5, and 5.0 × 106 sperm dosages, respectively). Among cows, a total of 2,369 services were retrieved from 56 herds (263 ± 8.8 services/sperm dose per sire, range: 233 to 303). Conception rates of cows (29.4%) were not affected by sire or sperm dosage (27.0, 29.1, and 30.3% for the 2.1, 3.5, and 5.0 × 106 sperm dosages, respectively). In conclusion, these data indicate that an increased sperm dosage may enhance virgin heifer conception rates for some (but not all) sires, whereas neither sire nor sexed-sperm dosage affected conception rates of lactating cows. Additional studies of sexed-sperm dosage across a larger sampling of bulls are warranted to determine whether and how such a practice can be implemented cost effectively for the benefit of the dairy industry. 相似文献
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Survey on the content of vitisin A and hydroxyphenyl-pyranoanthocyanins in Tempranillo wines 总被引:1,自引:0,他引:1
Michael Rentzsch Michael Schwarz Peter Winterhalter Dora Blanco-Vega Isidro Hermosín-Gutiérrez 《Food chemistry》2010
Little is known about the content and development of pyranoanthocyanins, pigments mainly formed during red wine ageing, in commercial wines. Some of the major pyranoanthocyanins in a wide selection of 1–10 years-old Spanish Tempranillo wines and also in a 29 years wide-vertical series of Tempranillo wines from an individual cellar have been determined. Great variability in pyranoanthocyanin concentrations was found (range, mg/l): vitisin A, 0–10.76; pinotin A, 0–4.26; and malvidin 3-glucoside-4-vinylphenol, 0.03–1.37. Vitisin A and malvidin 3-glucoside-4-vinylphenol were already present in 1–2 years-old wines, whereas pinotin A was only detectable in a few of the 1 and 2 years-old wines. Vitisin A tended to decrease with wine age, while hydroxyphenyl-pyranoanthocyanins showed the reverse trend. However, the aforementioned trends were interrupted by various temporary maxima, most likely due to some “refreshment” of the oldest wines (i.e., addition of young wine), as suggested by unexpected high concentrations of malvidin 3-glucoside, in contrast to the results found in the wine vertical series. The effects of addition of young wine on aged wine pyranoanthocyanin concentrations were confirmed by wine refreshment experiments. 相似文献
26.
Helena M. Moreno José Carballo A. Javier Borderías 《Innovative Food Science and Emerging Technologies》2010,11(2):394-400
Changes in physicochemical properties of raw-appearing restructured models made from hake (Merluccius capensis) muscle, using cold gelation technology by addition of sodium alginate and microbial transglutaminase (MTGase), were studied during frozen storage at ? 15 °C.Among the more interesting results, addition of MTGase produced more protein aggregation in models processed by muscle homogenization and thus the protein network that formed in the gel was better than in samples with added sodium alginate. All samples presented enhanced changes in mechanical properties such as gel strength in the course of frozen storage. The protein network that formed was better organized as shown by the ultrastructure analysis and by protein aggregation data from the beginning of storage, and as a result Water Binding Capacity was greater in restructured models processed by muscle homogenization. Some of the models studied presented lipid oxidation during frozen storage, slightly more in the ones with MTGase added.Industrial RelevanceThe industrial relevance of the present work is to establish bases for using fish fillet trimmings and minced muscle to prepare restructured products that can be commercialized in a raw state and that could also support frozen storage in order to prolong the self-life in the market. The models studied here are not final products but the base with which to prepare them. One possibility of them is to process this kind of products with technologies normally used in whole fish muscle such as smoked fish fillets, carpaccios or marinated products. In addition, these raw restructured products can be commercialized to be cooked as a normal fresh fish fillet or pieces of fillet in a variety of preparations, and also products that contain a high amount of salt. Samples elaborated by binding larger muscle fragments imitate well the original fibrousness of the muscle so that it could be used to elaborate products similar to hamburgers or others that will be fried in batter. 相似文献
27.
González-Fandos ME Sierra ML García-López ML Otero A Sanz J Moreno B 《Meat science》1996,43(3-4):255-263
The effect of meat cultures (non lactic acid bacteria) on the growth and production of enterotoxins and thermonuclease by Staphylococcus aureus was studied. Micrococcus varians did not affect growth nor the synthesis of metabolites. Levels of enterotoxins A, B and D produced by the respective S. aureus strains were reduced by S. xylosus, S. saprophyticus and S. carnosus. The two latter species prevented production of enterotoxin C1 and S. xylosus markedly reduced the amount produced. The three coagulase-negative staphylococci showed little inhibitory effect on the growth of S. aureus. Penicillium nalgiovense did not show inhibitory activity against the four S. aureus strains. Debaryomyces hansenii slightly inhibited growth of the enterotoxin A-producing strain, but reduced enterotoxin synthesis at 30 °C. Thermonuclease was detected whenever enterotoxins were detected though the influence of the effector organism was dependent on the test strain. 相似文献
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Juana Bernabé Juana Mulero Begoña Cerdá Cristina García-Viguera Diego A. Moreno Soledad Parra Francisco Avilés Angel Gil-Izquierdo José Abellán Pilar Zafrilla 《Journal of Functional Foods》2013,5(3):1031-1038
Bioactive substances found in numerous foods can be successfully and safely used to modify various cellular functions and affect the oxidative stress. The aim of this study was to analyze the effect of a citrus-based juice (juice citrus (95%) with 5% of aronia extract (Aronia melanocarpa)) on biomarkers of oxidative stress in patients with metabolic syndrome compared with healthy individuals. The study comprised 20 healthy subjects and 33 patients with metabolic syndrome. Eighteen patients consumed daily 300 mL of a citrus-based juice during 6 months and 15 patients consumed 300 mL of a placebo beverage. The control group consumed a citrus-based juice (CJ). Before, and at sixth months after consuming of a citrus-based juice the following parameters were determined: 15-isoprostane F2, 8-hydroxydeoxyguanosine (8-OHdG), reduced and oxidized glutathione (GSH/GSSH), carbonyl groups and oxidized LDL (ox-LDL). After consuming CJ during 6 months the values of 8-OHdG, carbonyl groups and LDL-ox decreased in both analyzed groups and the values of GSH/GSSH increased. Significant differences were observed in both groups. Thus consumption of citrus-based juice improved the biomarkers of oxidative stress in metabolic syndrome patients. 相似文献
30.
Isabel Comino Ana Real Maria de Lourdes Moreno Raquel Montes Ángel Cebolla Carolina Sousa 《Journal of the science of food and agriculture》2013,93(4):933-943
BACKGROUND: Cereals used for beer manufacturing contain gluten, which is immunotoxic for celiac patients. The gluten remaining after processes of malting and brewing is mostly hydrolyzed, which makes practical evaluation of the immunotoxicity of the gluten pools challenging. RESULTS: We analyzed the presence of gluten peptides equivalent to the major immunotoxic protease‐resistant gliadin 33‐mer in 100 Belgium beers, using monoclonal antibodies (G12/A1). Immunochromatographic strips and enzyme‐linked immonosorbent assay G12/A1 methods estimated at least 20 ppm gluten equivalents in 90 beers and gluten‐free in 10 beers. The G12/A1 reactivity of beer high‐performance liquid chromatographic fractions correlated to the presence of T‐cell‐reactive epitopes identified by peptide sequencing. CONCLUSION: The determination of equivalent gliadin 33‐mer epitopes in beers has been shown to be practical, specific, and sensitive for the measurement of potential immunotoxicity for celiac patients. Copyright © 2012 Society of Chemical Industry 相似文献