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451.
As a further step in developing a systems model of privacy, variables involved in the process of achieving a condition of privacy were examined cross-culturally. Subjects were students from Ireland, Senegal and the United States. Striking commonalities were found in the reasons why subjects required privacy, the affect that was associated with a desire for privacy, the definition of privacy as a condition of the person, the duration of the average privacy experience and the change in affect at the completion of the experience which supported the suggestion that privacy has a therapeutic effect. Within culture, variability was associated with age, gender and in the case of Senegal, with income. Between culture, variability was hardly noticeable. The majority of the subjects in each culture believed that not being disturbed was the most important element of privacy and grief, fatigue and need to focus were the main affective sets associated with seeking privacy. It is believed that several universals have been identified which may be used in later research, and that the study supports a systems-based model of privacy.  相似文献   
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This analysis examines the ability of previous offenses to predict future high-risk offenses, and similarly, the ability of crashes to predict future high-risk crashes, using the complete driver history data (up to 9 years) for a set of young Michigan subjects. As expected, those with previous ticketed offenses or reported crashes are at greater risk for future offenses or crashes; with a previous-year serious offense doubling the odds of serious offenses during the subsequent year, and a previous-year at-fault crash increasing the odds of subsequent-year at-fault crashes by nearly 50%. There is modest evidence that serious offenses and at-fault crashes may better predict subsequent behavior in females and in more experienced drivers. This latter finding is also evidenced by the fact that records of these young drivers are less predictive of subsequent driving history than is true for records of all drivers in general found in other studies. This suggests that, in the early stages of driving, offenses and crashes are, at least in part, attributable to inexperience, and hence, characteristic of all beginning drivers.  相似文献   
454.
This paper discusses the early research that lead to graduated driver licensing, some of the educational principals on which it is based, obstacles to its acceptance, and some of the early efforts in the U.S. and elsewhere. EARLY RESEARCH: The research underlying the concept of graduated driver licensing was a 1971 North Carolina study that identified the overrepresentation of young drivers in crashes at night and when another young person was the right front passenger. EDUCATIONAL PRINCIPALS: Efforts to reduce the risk to young novice drivers applied what was known about learning. The concepts included distributed learning (i.e., over time) and progressing from simple to complex skills. A PROPOSAL: The proposed graduated licensing system based on learning principals included (a) initial experience under low risk conditions, (b) extended supervised practice, (c) gradual move to more complex conditions, and (d) harsher penalties for deliberate risk-taking. OBSTACLES: There were several most common objections raised against graduated licensing. Raising the licensing age decreased mobility. Some young drivers were "good" drivers. Enforcement is difficult. Fear of parental objections. Parents are not driver educators and some young people do not have an available parent. Administrative costs are too high. ACCEPTANCE: Driver educators were the first to see the benefits of a graduated system in the 1970s and 1980s. Toronto nearly adopted a graduated system in 1976. New Zealand was the first to adopt a graduated licensing system in 1984. Michigan in 1997 was the first state to require parental certification of extended supervised driving practice.  相似文献   
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The present study aimed to gather information on drug and alcohol use, the prevalence of drink and drug driving and attitudes to both in an undergraduate university cohort (n = 275). Further, the study aimed to contribute information to aid intervention program development by determining predictors of drink and drug driving behavior. The study examines both drug and alcohol use and the influence of attitudes toward driving while under the influence of alcohol and/or drugs. Results indicated that significant proportions of university students are engaging in the risk-taking behavior of driving under the influence of drugs (25%), alcohol (14%), or both (8%). The results suggest that attitudes toward driving under the influence of alcohol and/or drugs are a strong predictor of engaging in the behavior. Peer influence emerged as a major aspect of attitudes. The results of this study provide an important beginning to understanding drink and drug driving and the influence of attitudes in the university student body.  相似文献   
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Three treatment media, used for the removal of arsenic from drinking water, were sequentially extracted using 10 mM MgCl2(pH 8), 10 mM NaH2PO4(pH 7) followed by 10 mM (NH4)2C2O4(pH 3). The media were extracted using an on-line automated continuous extraction system which allowed the arsenic in each of the extraction fluids to be speciated on-line using IC-ICP-MS. The 10 mM MgCl2 preferentially extracted As(III) from each of the media. The percentage of the arsenic extracted by the MgCl2, relative to a HNO3/H2O2 digestion of the media, ranged from 0.1-2.3% for the three solids. The next sequential extraction fluid, 10 mM NaH2PO4, extracted some of the residual As(III) remaining on each of the media but the predominant species extracted was As(V). The 10 mM NaH2PO4 extracted 15.3 to 42.8% of the total arsenic relative to a total digested concentration for each of the media. The As(III) and As(V) stability studies conducted in these two extraction fluids indicated that conversion between As(III) and As(V) was not significant for the short extraction fluid sample contact time associated with the on-line continuous flow extraction cell. Finally, the 10 mM (NH4)2C2O4 extraction fluid was utilized in an off-line analysis mode because the Fe and As concentrations extracted from the media were not compatible with direct ICP-MS detection. The (NH4)2C2O4 extracted 2.9-29% As(III) for all three media and caused an oxidation of As(III) to As(V) during the extraction period for one of the three media. The sum of the arsenic from each of the three extraction fluids represented 92%, 44% and 53% of the available total arsenic for the three media, respectively. The speciation results for each media were obtained by adding all the speciation results from all three extraction fluids together and the resulting distribution of As(III)/As(V) compared well with the speciation results obtained via XANES.  相似文献   
458.
The objective of this work is double—firstly to explore the photocatalytic efficiency of five different commercial TiO2 catalysts in the photodegradation of a mixture of pesticides classified by the EU as priority pollutants and secondly to analyze the correlation between their physicochemical properties and the inhibition of the studied photocatalytic process when natural water was employed. Photocatalytic efficiencies when ultrapure water was used seem to point out that surface area was not a prerequisite for the photodegradation of the selected mixture of pesticides. On the other hand, significant differences in total organic carbon (TOC) conversions were obtained with the two studied water compositions. On one side, Evonik materials appear to be mostly inhibited when natural water was employed, whereas on the other, it should be remarked that anatase Sigma-Aldrich (SA) and, particularly, Hombikat UV100 (HBK) materials presented a very limited photo-efficiency inhibition or even a higher initial rate of TOC removal when a natural water matrix was used, probably due to their specific surface properties (PZC, S BET). Therefore, heterogeneous photocatalysis has proved to be a promising technology for the degradation of the selected mixture of pesticides where the final photo-efficiency of the five commercial titania catalysts studied here responds to a complex balance between its surface and structural properties.  相似文献   
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