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101.
Kunick C Zeng Z Gussio R Zaharevitz D Leost M Totzke F Schächtele C Kubbutat MH Meijer L Lemcke T 《Chembiochem : a European journal of chemical biology》2005,6(3):541-549
In order to perform computer-aided design of novel alsterpaullone derivatives, the vicinity of the entrance to the ATP-binding site was scanned for areas that could be useful as anchoring points for additional protein-ligand interactions. Based on the alignment of alsterpaullone in a CDK1/cyclin B homology model, substituents were attached to the 2-position of the parent scaffold to enable contacts within the identified areas. Synthesis of the designed structures revealed three derivatives (3-5) with kinase-inhibitory activity similar to alsterpaullone. The novel 2-cyanoethylalsterpaullone (7) proved to be the most potent paullone described so far, exhibiting inhibitory concentrations for CDK1/ cyclin B and GSK-3beta in the picomolar range. 相似文献
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Argues that the reliability and validity of behavioral ratings as an assessment technique can be demonstrated when assessments are based on multiple raters and are validated against frequency counts based on adequate samples of behavior. This argument is illustrated by the observations of dependency and dominance in 56 preschoolers by 9 trained undergraduate observers. Besides supporting the reliability and validity of scores based on multiple ratings, the analyses also indicated that small samples of behavioral observations did not capture the stability of personality characteristics. Methodological implications for the use of ratings and behavior counts and conceptual implications for the consistency of personality are discussed. (34 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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The licensing of psychologists has become an area of intense professional interest. Attempts to provide historical overviews and current data on the status of licensing regulations have become common. This article critiques existing regulations by examining assumptions implicit in the development of licensing procedures. The implications of such assumptions for professional psychology are discussed, and guidelines for alternative licensure developments are presented. The importance of developing valid measures of entry-level and continued professional competence is emphasized. (27 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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J H Harrison D D Hancock N St Pierre H R Conrad W R Harvey 《Journal of dairy science》1986,69(5):1421-1425
Selenium injections and oral vitamin E supplementation prepartum were related to: postpartum uterine involution (decrease in uterine size per unit time) and days to minimum uterine size in a 2 X 2 factorial design. Complete data were analyzed from 64 cows. Groups were selenium plus vitamin E, vitamin E, selenium, and control. Factors significantly affecting uterine size between 14 and 50 d postpartum were cow weight, days postpartum-linear, days postpartum-quadratic, day X metritis, and day X metritis X selenium treatment. Days to minimum uterine size were significantly less in cows with metritis and selenium treated when compared with cows with metritis and not selenium treated (32.9 vs. 35.8). 相似文献
109.
A series of partial least squares (PLS) models were employed to correlate spectral data from FTIR analysis with beef fillet spoilage during aerobic storage at different temperatures (0, 5, 10, 15, and 20 °C) using the dataset presented by Argyri et al. (2010). The performance of the PLS models was compared with a three-layer feed-forward artificial neural network (ANN) developed using the same dataset. FTIR spectra were collected from the surface of meat samples in parallel with microbiological analyses to enumerate total viable counts. Sensory evaluation was based on a three-point hedonic scale classifying meat samples as fresh, semi-fresh, and spoiled. The purpose of the modelling approach employed in this work was to classify beef samples in the respective quality class as well as to predict their total viable counts directly from FTIR spectra. The results obtained demonstrated that both approaches showed good performance in discriminating meat samples in one of the three predefined sensory classes. The PLS classification models showed performances ranging from 72.0 to 98.2% using the training dataset, and from 63.1 to 94.7% using independent testing dataset. The ANN classification model performed equally well in discriminating meat samples, with correct classification rates from 98.2 to 100% and 63.1 to 73.7% in the train and test sessions, respectively. PLS and ANN approaches were also applied to create models for the prediction of microbial counts. The performance of these was based on graphical plots and statistical indices (bias factor, accuracy factor, root mean square error). Furthermore, results demonstrated reasonably good correlation of total viable counts on meat surface with FTIR spectral data with PLS models presenting better performance indices compared to ANN. 相似文献
110.
Effect of different coagulants on the isoflavone levels and physical properties of prepared firm tofu 总被引:1,自引:0,他引:1
The objective of this study was to understand the effect of different coagulants in their ability to retain isoflavones in prepared firm tofu. Harovinton beans were processed to obtain soymilk and a specific amount of this soymilk was coagulated using different types of coagulants for the preparation of tofu. A reversed phase high performance liquid chromatographic method was used for determining the concentration of isoflavones in tofu and whey. Quality parameters such as the texture, color and moisture of tofu, prepared from different coagulants were also determined in this study. Tofus coagulated with different coagulants were found to contain different amounts of isoflavones. Calcium sulfate was found to be the most suitable coagulant for tofu making in terms of its high yield, retention of maximum amount of isoflavones and in obtaining a firm, but not hard texture of tofu. 相似文献