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41.
Novel photoactive polymers were prepared by covalently binding an anthraquinone (AQ) derivative through its 2-position to acid groups of a commercially available ethylene–acrylic acid copolymer, and the photodynamic action of films prepared using these polymers was evaluated. Inoculation of Bacillus cereus spores onto the surface of photoactive polymer films having an AQ content of 35% w/w, followed by exposure to low-power UV-A light, was found to significantly enhance the inactivation of the spores compared with their survival on the surface of inert polymer substrates. It was shown that this effect most likely originates from the photo-induced production of singlet oxygen by the photoactive polymer. These results provide compelling evidence that singlet oxygen produced exogenously by a polymeric substrate can successfully inactivate microbes located on the substrate’s surface.  相似文献   
42.
"The present study investigated the capacity of human Ss to judge the emotional quality of stimuli presented too briefly [tachistoscopically] and at illumination levels too low for correct specific identification… . After the exposure of each word, the Ss were required to judge whether the word was pleasant or unpleasant as well as to guess what the word was… . the results revealed that in the absence of specific recognition or identification of the stimuli, the Ss' affective judgments were more often correct than could be attributed to chance." (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
43.
Considers the prediction problem in the case of designated aviators who are not successful in the replacement air group (RAG), or postgraduate, phase of instruction. The sample group consisted of 592 naval jet aviators assigned to RAG training in East and West Coast squadrons. Employing multiple correlation analysis to examine RAG completion as a remote criterion variable, undergraduate training grades significantly predicted RAG completion. Had the obtained regression weights been employed, the attrition rate of a cross-validation sample would have been reduced by 33.8%. Those skills in undergraduate training that were "mission oriented" as opposed to academic or flight skills contributed the most to the explained criterion variance. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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This paper describes a new approach in life-cycle impact assessment to derive characterization factors for acidification in European forests. Time horizon dependent characterization factors for acidification were calculated, whereas before only steady-state factors were available. The characterization factors indicate the change in the potential occurrence of plant species due to a change in emission, and they consist of a fate and an effect factor. The fate factor combines the results of an atmospheric deposition model and a dynamic soil acidification model. The change in base saturation in soil due to an atmospheric emission change was derived for 20, 50, 100, and 500 year time horizons. The effect factor was based on a dose-response curve of the potential occurrence of plant species, derived from multiple regression equations per plant species. The results showed that characterization factors for acidification increase up to a factor of 13 from a 20 years to a 500 years time horizon. Characterization factors for ammonia are 4.0-4.3 times greater than those for nitrogen oxides (NO(x)), and characterization factors for sulfur dioxide are 1.4-2.0 times greater than those for NO(x). Aggregation of damage due to acidification with other impact categories on the European scale becomes feasible with the applied approach.  相似文献   
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Early attempts at controlling the sea lamprey (Petromyzon marinus) in the Great Lakes in the 1950s centered on a variety of mechanical and electrical devices to prevent migration of adults into tributary streams to reproduce. Although some of the devices were effective, it became obvious that barriers alone were not an adequate solution to the lamprey predation problem. Researchers screened over 6,000 chemicals before they found 3-trifluoromethyl-4-nitrophenol (TFM), a toxicant to which sea lamprey larvae and adults are particularly sensitive. Bayer 73 enhances lampricidal activity when used in combination with TFM. In 1970, the U.S. Environmental Protection Agency (EPA) required additional studies to support continued use and registration of TFM. Most of these studies have been completed, but the EPA could cancel the existing registration in the event of unforeseen problems or hazards associated with its use. Therefore, the Great Lakes Fishery Commission continues to support research on lamprey control techniques, such as new formulations of TFM and Bayer 73, sterile male techniques, and attractants and repellents. Development of an integrated management program to combat the sea lamprey is being planned. This concept involves the systematic application of multiple techniques in a way that will exert maximum impact on the sea lamprey. Possible programs may involve chemical, biological, and physical control techniques, each of which would be subject to its own registration or regulatory requirements.  相似文献   
48.
The authors examined how the structure of mother–adolescent conversations differs by ethnic group, age, and dyadic and individual factors. Mother–adolescent dyads of European or Latino descent participated in conversations and reported on their relationship and AIDS knowledge. Latina American mothers dominated conversations more than European American mothers, independent of socioeconomic status. Mothers dominated conversations about sexuality and AIDS more than conversations about conflicts. Mothers of older adolescents reacted more negatively, and older adolescents reported less satisfaction, less openness, and more sexual discussions with persons other than their mothers. Latino American adolescents whose mothers dominated conversations more reported fewer sexual discussions. Latina American mothers who dominated conversations more reported more openness and satisfaction. When mothers dominated conversations more, adolescents had lower AIDS knowledge. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
49.
In this work, the use of laser-induced breakdown spectroscopy (LIBS) to differentiate live pathogens and killed viruses on substrates is investigated. Live pathogens B. anthracis Sterne strain and F. tularensis live vaccine strain were interrogated as lawn and colonies on agar; dilutions on agar; and dilutions on glass slides, and it was found possible to differentiate among all samples. UV killed hantavirusstrains were studied as dilutions on slides and it was also found possible to differentiate among strains. To the best of our knowledge, this is the first study in which LIBS has been used to differentiate virus samples.  相似文献   
50.
This paper analyses the enabling conditions for a water governance model responsive to future Philippine water requirements. Using the stage-based approach to institutional reforms, it assesses the outcomes of previous water governance reforms, such as conflicts in customary and formal rules; urban and rural; upstream and downstream; and the contestations in water supply privatization in Metro Manila. The analysis suggests that past water governance reforms were symbolic and procedural, and structural changes to support the legal frameworks were not achieved. Based on the case findings, the authors support the current reform agenda of implementing a decentralized framework of water governance at a watershed scale.  相似文献   
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