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This paper proposes a new approach to the schema translation problem. We deal with schemas whose metaschemas are instances of the OMG’s MOF. Most metaschemas can be defined as an instance of the MOF; therefore, our approach is widely applicable. We leverage the well-known object-oriented concepts embedded in the MOF and its instances (object types, attributes, relationship types, operations, IsA hierarchies, refinements, invariants, pre- and postconditions, etc.) to define metaschemas, schemas and their translations.The main contribution of our approach is the extensive use of object-oriented concepts in the definition of translation mappings, particularly the use of operations (and their refinements) and invariants, both of which are formalized in OCL. Our translation mappings can be used to check that two schemas are translations of each other, and to translate one into the other, in both directions. The translation mappings are declaratively defined by means of pre- and postconditions and invariants, and they can be implemented in any suitable language. From an implementation point of view, by taking a MOF-based approach we have a wide set of tools available, including tools that execute OCL. By way of example, we have defined all schemas and metaschemas in this paper and executed all the OCL expressions in the USE tool. 相似文献
113.
Brébion Gildas; Ohlsen Ruth I.; Pilowsky Lyn S.; David Anthony S. 《Canadian Metallurgical Quarterly》2008,22(3):383
Objective: An association between hallucinations and reality-monitoring deficit has been repeatedly observed in patients with schizophrenia. Most data concern auditory/verbal hallucinations. The aim of this study was to investigate the association between visual hallucinations and a specific type of reality-monitoring deficit, namely confusion between imagined and perceived pictures. Method: Forty-one patients with schizophrenia and 43 healthy control participants completed a reality-monitoring task. Thirty-two items were presented either as written words or as pictures. After the presentation phase, participants had to recognize the target words and pictures among distractors, and then remember their mode of presentation. Results: All groups of participants recognized the pictures better than the words, except the patients with visual hallucinations, who presented the opposite pattern. The participants with visual hallucinations made more misattributions to pictures than did the others, and higher ratings of visual hallucinations were correlated with increased tendency to remember words as pictures. No association with auditory hallucinations was revealed. Conclusions: Our data suggest that visual hallucinations are associated with confusion between visual mental images and perception. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
114.
Studied the effects of attention during encoding and rehearsal after initial encoding on frequency estimates in 3 experiments. Exp I found that varying the level of processing affected the linear increase in frequency estimates as a function of actual frequency, but varying processing after encoding with remember or forget cues had the greatest effects on the intercept of the function relating judged to actual frequency. Deeper levels of processing improved performance in a frequency discrimination task, whereas remember and forget cues had small effects on performance. In Exp II, materials that are easy to rehearse were compared with materials that are difficult to rehearse. Results were interpreted as evidence against a covert rehearsal explanation of slope effects in frequency estimation tasks because materials that are difficult to rehearse produced larger interactions between remember vs forget cues and frequency than materials that are easier to rehearse. In Exp III, an arithmetic task that was performed during word encoding affected the slope of the function relating judged to actual frequency, but the same task performed immediately after word presentation had no effect on frequency estimates. It is concluded that frequency is not stored automatically because attention during the initial stages of encoding affects it; however, attention devoted to processing after initial encoding does not affect the rate with which subjective frequency increases with repetitions. (22 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Investigated whether and how pictures are mentally rotated to upright before they can be named. Four experiments were conducted with 12 college students in each, who were given the tasks of naming pictures of common objects with various orientations and locating their tops. In the naming task, Ss required more time the farther the picture was from upright, but the rotation effect was reduced after Ss had named each picture once, indicating that rotation may be required only for unfamiliar stimuli. The top locating task was faster with upright figures, but otherwise-oriented pictures required the same time regardless of orientation. Top-locating was faster than naming, indicating that "topness" may be guessed even in unfamiliar figures, while naming also involves searching one's semantic memory for a name. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
117.
Evaluation of elemental profile coupled to chemometrics to assess the geographical origin of Argentinean wines 总被引:1,自引:0,他引:1
María P. Fabani Ruth C. Arrúa Fabio Vzquez María P. Diaz María V. Baroni Daniel A. Wunderlin 《Food chemistry》2010,119(1):224
Traceability of wines requires knowledge of their characteristics, which are associated with the geographical origin of grape, soil, water, climate as well as the winery techniques. The aim of this work was to classify wines and soil from three production areas of Argentina according to multielement data. The influence of the provenance soil on the wine element composition was also investigated.Eleven elements were determined in 31 wine samples and 137 soil samples from regions under study. Stepwise discriminant analysis allows us to correctly classify 100% of the wines analysed from the three regions using only seven parameters (K, Fe, Ca, Cr, Mg, Zn and Mn) and 92% correct classification for soils using seven variables (Ca, Cr, K, Fe, Cu, Zn and, Mg). Canonical analysis between soils and wines datasets affords a correlation coefficient of 0.85 (P-value < 0.001). Thus, almost 85% of variability observed amongst wines could be attributed to the soil in which the vines were cultivated.The analysis of elemental concentrations in the wines and soils, in combination with chemometrics, provides a powerful tool to verify the geographical origin of wines. 相似文献
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119.
Michael R. A. Morgan Ruth McNerney Henry W.-S. Chan Peter H. Anderson 《Journal of the science of food and agriculture》1986,37(5):475-480
An indirect, double antibody enzyme-linked immunosorbent assay (ELISA) has been validated for application to pig kidney. The specificity of the anti-ochratoxin A antiserum employed is such that minimal sample preparation is required prior to assay, with consequent beneficial effects on sample throughput. Kidneys (303) obtained in the UK as being unsuitable for human consumption were examined for ochratoxin A content by ELISA. Of these, 191 (63%) contained no detectable toxin (the detection limit was 0.5 ng g?1). Only eight samples (2.6%) contained more than 5 ng g?1 ochratoxin A, and only two were above 10 ng g?1 (at 11.5 and 12.4 ng g?1). The significance of these findings is discussed. 相似文献
120.
Two experiments examined the effect of reinforcer devaluation on the ability of a discriminative stimulus (Sd) to control instrumental behavior in Sprague-Dawley rats. In Experiment 1 reinforcer devaluation reduced, but did not eliminate, the ability of the Sd to control performance of the original response and to transfer its control to a new response trained with the same reinforcer. The effect of devaluation was more complete in Experiment 2, in which the reinforcer was delivered directly into the oral cavity. However, retraining the response with a different reinforcer partially restored the ability of the Sd to control performance of that response. These results suggest that an Sd may not augment its trained responses when the reinforcer has been completely devalued but may promote responses with which it shares a reinforcer, as long as those responses are associated with some reinforcer that retains its value. The implications of these results for the way that discriminative stimuli control instrumental behavior are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献