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Dermal exposure to pesticides is one of the main sanitaryproblems which greenhouses workers face. With the dual aimsof establishing both the body part that receives the greatestexposure and the variable that has greatest influence on this exposure level, 22 pesticide application trials were performed. Trials were carried out in different greenhouse vegetable crops,using different pesticides and different spray diameters from the spray gun. In order to determine dermal exposure, the wholebody method was used. Pieces of the applicator suit were subject to an extraction procedure and their pesticide contentdetermined using GC-NPD analysis. Multivariate analysis were applied to the data obtained. Principal component analysis showed that all trials produced a high exposure level on lowerleft leg and lower right leg. Cluster analysis distinguished between three sample groups. The most and the least affectedparts were clearly distinguished. Discriminant analysis indicated that the thin drop size of the spray gun is responsible for both the differences between groups and the minimum or maximum exposure level measured on the applicatorsuit. Therefore, selecting the variables, lower legs and thindrop size, is considered fundamental in designing programs formonitoring pesticide exposure.  相似文献   
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Organizational justice is an important determinant of workplace attitudes, decisions, and behaviors. However, understanding workplace fairness requires not only examining what happens but also when it happens, in terms of justice events, perceptions, and reactions. We organize and discuss findings from 194 justice articles with temporal aspects, selected from over a thousand empirical justice articles. By examining temporal aspects, our findings enrich and sometimes challenge the answers to three key questions in the organizational justice literature relating to (i) when individuals pay attention to fairness, including specific facets, (ii) how fairness judgments form and evolve, and (iii) how reactions to perceived (in)justice unfold. Our review identifies promising avenues for empirical work and emphasizes the importance of developing temporal theories of justice. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
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Land cover change in the Brazilian Amazon depends on the spatial variability of political, socioeconomic and biophysical factors, as well as on the land use history and its actors. A regional scale analysis was made in Rondônia State to identify possible differences in land cover change connected to spatial policies of land occupation, size and year of establishment of properties, accessibility measures and soil fertility. The analysis was made based on remote sensing data and household level data gathered with a questionnaire. Both types of analyses indicate that the highest level of total deforestation is found inside agrarian projects, especially in those established more than 20 years ago. Even though deforestation rates are similar inside and outside official settlements, inside agrarian projects forest depletion can exceed 50% at the property level within 10–14 years after establishment. The data indicate that both small-scale and medium to large-scale farmers contribute to deforestation processes in Rondônia State encouraged by spatial policies of land occupation, which provide better accessibility to forest fringes where soil fertility and forest resources are important determinants of location choice.  相似文献   
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The energetic parameters, such as glycogen, glucose, proteins, lactate and adenosine triphosphate (ATP) content and lactate deshydrogenase (LDH) activity in tissues and blood of carps from simazine (2-chloro-4,6-bis(ethylamino)-s-triazine) contaminated waters were investigated. In order to confirm the field results, a laboratory experiment was designed in which carps were exposed to simazine at the concentration level of 45 μ g. L? 1 (10-fold of the amount found in natural waters) for 90 days. Fish from a contaminated reservoir showed low glycogen concentrations in hepatopancreas and muscle, while fish in another contaminated reservoir showed high LDH activity together with an increase in lactate content in muscle. Laboratory findings did not confirm field results, and fish exposed to simazine did not show alterations in the parameters studied. The results suggest that carps were not stressed by the presence of the simazine at the concentration levels found in both studies and the mechanisms of defense covered the energetic demand.  相似文献   
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Environmental Science and Pollution Research - In the present study, mercury (Hg), cadmium (Cd), lead (Pb), selenium (Se), and arsenic (As) were measured in liver, kidney, and feathers of adult,...  相似文献   
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We investigated the variation in concentrations and profiles of various classes of organohalogenated compounds (OHCs) in different feather types, muscle tissue and preen oil from 15 white-tailed eagle (Haliaeetus albicilla) carcasses from Greenland. The influence of moult patterns and potential external contamination onto the feather surface was examined, while the present study is also the first to investigate the use of body feathers for OHC monitoring. Concentrations of sum polychlorinated biphenyls (PCBs) in feathers from white tailed eagles ranged from 2.3 ng/g in a primary wing feather to 4200 ng/g in body feathers. Using 300 mg of body feathers, almost 50 different OHCs could be quantified and median concentrations in body feathers were 10 fold higher than concentrations in tail feathers (rectrices) or primary wing feathers. Body feathers could be very useful for biomonitoring taking into account their easy sampling, short preparation time and high levels of OHCs. In addition, the effects of confounding variables such as feather size, moult and age are also minimised using body feathers. Correlations with concentrations in muscle tissue and preen oil were high and significant for all feather types (r ranging from 0.81 to 0.87 for sum PCBs). Significant differences in concentrations and profiles of OHCs were found between different primary feathers, indicating that the accumulation of OHCs in feathers varies over the moulting period (maximum three years). Washing of feathers with an organic solvent (acetone) resulted in a significant decrease in the measured concentrations of OHCs in feathers. However, our results indicated that preen oil is probably not the only contributor to the external contamination that can be removed by washing with acetone. Possibly dust and other particles may be of importance and may be sticking to the preened feathers. Rectrices washed only with water showed high and significant correlations with concentrations in muscle and preen oil as well. Washing with acetone therefore does not seem to be of great influence when relating to internal tissue concentrations. We recommend washing feathers only with distilled water in order to remove dirt and dust particles before analysis.  相似文献   
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