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81.
This article presents an evaluation and proposals for improving a method for assessing health and safety management systems. This method takes resilience engineering (RE) as its underlying philosophy and was originally devised and tested in a case study of a manufacturing plant. Four main changes were proposed in comparison with the original version of the method: (a) a framework for assessing the use of RE principles more systematically; (b) guidelines for developing an action plan as a result of the assessment; (c) re-organization of the data collection tools in order to increase their ease of use; and (d) procedures for facilitating the assignment of scores to the items assessed. The evaluation of the method, which was not restricted to the changes described in this article, was conducted based on seven criteria for evaluating safety assessment tools. Both the evaluation and the impact of the changes are discussed based on a case study, in which the method was applied in a company that distributes electricity.  相似文献   
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This study addresses coping processes as explanation of age‐related differences in strain experience. Based on the life‐span theory of control, we posit that older workers employ more active problem‐focused and more active emotion‐focused coping strategies than younger workers, which should mediate age effects on strain at work. The correlation between age and passive avoidance coping, in contrast, is expected to be qualified by external resources such as job control. Hypotheses were tested in a two‐wave panel study (8 months lag) with 634 workers (age range 16–65 years). Job demands were considered as control variables. As predicted, older as compared with younger workers reported more active problem‐focused coping, which mediated age differences on strain in the longitudinal analysis. No mediation was found for active emotion‐focused coping. Moreover, age‐contingent effects of passive avoidance coping were moderated by job control. When job control was low, younger as compared with older workers reported more avoidance coping, which in turn decreased strain in the longitudinal analysis. Finally, reverse longitudinal effects of age‐contingent strain on active problem‐focused and active emotion‐focused coping provide initial evidence for age‐contingent resource spirals. Together, the results reveal specific strengths of older workers for stress management at work. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
85.
Acute exposure to waterborne copper is followed by a reduction in heart rate in gastropod limpets. In order to understand the mechanism of this effect, exposure to copper (0.25 or 0.5 mg l(-1); for 3 and 6 h) was combined with an injection of tetrodotoxin (TTX, 20 microl, 0.5 or 1 microM), a natural toxin that inhibits the propagation and transmission of impulses in excitable tissues. Experiments were performed on the Mediterranean limpet Patella caerulea, using a non-invasive method for the recording of cardiac activity. TTX did not affect the bradycardic effect of the cholinergic agonist carbachol. However, this toxin significantly antagonized the bradycardia induced by 0.25 and 0.5mg l(-1) of copper exposure and prevented the acardia observed in some limpets exposed to 0.5mg l(-1) of copper for 6h. These results are consistent with the hypothesis that the inhibitory action of copper on limpet cardiac activity involves an extrinsic, cholinergic neuronal control.  相似文献   
86.
Journal of Material Cycles and Waste Management - In this work, the effectiveness of a rapid recycling method of waste polypropylene (WPP) with the addition of inorganic fillers was investigated....  相似文献   
87.
Spawning pattern (assessed by seasonal changes in ovarian developmental stages) and type of fecundity (assessed by analysis of oocyte-size frequency distributions) of the round herring Etrumeus teres were studied in relation to ovarian growth and seasonal changes in the gonadosomatic (GSI), hepatosomatic (HSI) and liposomatic (LSI) index as well as the somatic condition of spawners (CS) in a spawning ground of southern Japan. Except for summer, mature and recently spawned ovaries occurred all year round. Oogonia and primary oocytes were present in all ovaries, and cortical alveoli stage (CA) oocytes occurred in all mature, hydrated and partially spent (PS) females (PS: females containing post-ovulatory follicles). Before hydration, a clutch of larger yolked oocytes, undergoing synchronous growth (range 0.7–1.1 mm), was present in mature ovaries which was completely separated from a more heterogeneous clutch of oogonia, primary and secondary oocytes (<0.150 mm) and oocytes in the CA stage (range 0.15–0.60 mm). As vitellogenesis progressed, the yolked clutch increased in size but the CA oocytes remained arrested. The latter entered into the secondary growth phase when hydration started in the advanced batch. Ovarian growth was isometric in all developmental stages, validating the use of GSI, which showed a consistent monthly evolution among years. Spawning stopped in summer (July and August) and peaked in winter and spring. HSI correlated positively with GSI on both a monthly mean basis (r = 0.76) and individual fish basis (liver weight explained 67–83% of the variability in ovary weight when females were grouped into 1-unit GSI intervals) suggesting a significant role of liver in vitellogenesis. LSI and CS also showed marked seasonal changes peaking from summer to middle autumn. Overall results suggest that E. teres is a multiple spawner with a group-synchronous ovarian development and indeterminate annual fecundity, with the three processes linked to an isometric growth of the ovary. We propose that such a reproductive pattern is an adaptation to produce batches of large pelagic eggs through a protracted spawning season.  相似文献   
88.
Summary. Two Ceratosoma species, C. trilobatum and C. gracillimum (Mollusca: Gastropoda: Opistobranchia), collected along the South China Sea coast, have been studied in order to investigate their defensive strategies. Both species contain four typical sponge furanosesquiterpenoids, probably with a dietary origin. The tissue distribution of these compounds has been studied by 1H-NMR analysis and preliminary bioassays have been carried out in order to evaluate the ecological role of the isolated metabolites. The main sesquiterpene component in both species was (–)-furodysinin (2), which showed significant feeding-deterrent and ichthyotoxic properties in bioassays with freshwater organisms. The work has been performed studying a very limited number of molluscs that prevented the realization of ecologically relevant experiments. However, the almost exclusive presence of compound 2 in the crude extract of the mantle glands concentrated in the dorsal horn of C. gracillimum strongly supports the defensive role of that dorsal protuberance, which probably acts as a defensive lure attracting potential predators to the part of the animal that contains the distasteful chemicals.  相似文献   
89.
Summary Computerized screening of all the positions recorded during a synodic month on 120 individually marked chitons (Acanthopleura gemmata) pinpointed their preferential resting points. Unlike the majority of intertidal chitons so far studied, A. gemmata rests in well-defined homes actively dug in the rock. Homes proved to be not strictly individual and periodically interchangeable. A complex aggressive behaviour was recorded in the field when two animals came in contact at home. When competing for ownership of a resting site rival chitons may suppress their nocturnal feeding activity. Despite its strong home-related territoriality A. gemmata showed no mutual exclusion on the feeding area. The highly specialized resting habits clearly protects A. gemmata from its most important predator, the toad fish Arothron immaculatus. The behaviour of A. gemmata is compared to that of other chitons and gastropods, and the current hypotheses concerning the adaptive value of the homing behaviour in littoral molluscs are discussed.  相似文献   
90.
This paper statistically evaluates the sensitivity of the acute Daphnia magna bioassay in comparison to that of two crustacean microbiotests: the Streptoxkit F and Thamnotoxkit F, which make use of larvae of the anostracans Streptocephalus proboscideus and Thamnocephalus platyurus respectively, hatched from cysts. Regression equations were calculated for 146 data pairs, taken from 5 different studies dealing with the acute toxicity of pure chemicals, effluents, river sediments, solid wastes and monitoring wells, and sludges. All comparisons show that there is a significant relationship (p< 0.05) between the acute effects found with the D.magna and the two crustacean microbiotests; correlation coefficients ranged from 0.84 to 0.92.

In the majority of cases, effect ratios between the conventional D.magna and the microbiotests were within a factor 2 for both pure chemicals and environmental samples.

Variation coefficients for repeated tests on the reference chemical potassium dichromate indicate a good precision and hence a good degree of standardization of the microbiotest procedures. The evidence provided in this paper demonstrates that the new crustacean microbiotests can be used as low cost alternatives to the conventional D.magna acute assay.  相似文献   

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