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101.
As employees grow older, do their attitudes regarding work change over time? Can such long‐term changes be understood from a personality development perspective? The present study addressed these fundamental questions by tracking 504 young professionals' work attitudes (i.e., job satisfaction and work involvement) and Big Five personality traits over the first 15 years of their professional career. We specifically investigated whether trait changes drive peoples' changing attitudes, a mechanism we called maturation of work attitudes. Latent change models first indicated significant associations between traits and attitudes at the beginning of the career, and mean‐level changes in Big Five traits (i.e., increases in Agreeableness and Conscientiousness and decreases in Neuroticism) in the direction of greater functional maturity. Although no significant mean‐level changes in work attitudes were observed, results regarding correlated change indicated that variability in attitude change was related to variability in trait change and that this indeed signaled a maturational process. Finally, reciprocal effect estimates highlighted bidirectional relations between personality and attitudes over time. It is discussed how these results (i) provide a better understanding of potential age effects on work‐related attitudes and (ii) imply a revision of the traditional dispositional approach to attitudes. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
102.
In 1998, Greenpeace, Natuur en Milieu(Nature and Environment), Milieudefensie(Environmental Defense), and the National ConsumersUnion presented a report about the possible risks andhazards associated with pesticide residues on fruitsand vegetables. Although these organizationsexplicitly denied having unassailable evidence on theharmful effects of pesticides, they claimed that bynow there are sufficient indications that pesticidesmay indeed lead to such health hazards. They used anappeal to the so-called precautionary principle tounderpin their claims. The committee officially incharge of deciding on the admission of pesticidesaccused the organizations of scaremongering. Afterdistinguishing three possible versions of theprecautionary principle, we then show that the fourorganizations used in their campaign an improperversion of the precautionary principle to convince thegeneral public.  相似文献   
103.
Air quality improvement in Los Angeles can inform air quality policies in developing cities. Emission control efforts, their results, costs and health benefits are briefly summarized. Today's developing cities face new challenges including regional pollution. Air quality issues in Beijing are briefly compared and contrasted with Los Angeles. Opportunities for co-benefits for climate and air quality improvement are identified. Air quality improvement in Los Angeles, California is reviewed with an emphasis on aspects that may inform air quality policy formulation in developing cities. In the mid-twentieth century the air quality in Los Angeles was degraded to an extent comparable to the worst found in developing cities today; ozone exceeded 600 ppb and annual average particulate matter <10 mm reached ~150 mg·m−3. Today's air quality is much better due to very effective emission controls; e.g., modern automobiles emit about 1% of the hydrocarbons and carbon monoxide emitted by vehicles of 50 years ago. An overview is given of the emission control efforts in Los Angeles and their impact on ambient concentrations of primary and secondary pollutants; the costs and health benefits of these controls are briefly summarized. Today's developing cities have new challenges that are discussed: the effects of regional pollution transport are much greater in countries with very high population densities; often very large current populations must be supplied with goods and services even while economic development and air quality concerns are addressed; and many of currently developing cities are located in or close to the tropics where photochemical processing of pollution is expected to be more rapid than at higher latitudes. The air quality issues of Beijing are briefly compared and contrasted with those of Los Angeles, and the opportunities for co-benefits for climate and air quality improvement are pointed out.  相似文献   
104.
Direct mercury (Hg) speciation was assessed for soil samples with a Hg concentration ranging from 7 up to 240 mg kg−1. Hg chemical forms were identified and quantified by sequential extractions and bulk- and micro-analytical techniques exploiting synchrotron generated X-rays. In particular, microspectroscopic techniques such as μ-XRF, μ-XRD and μ-XANES were necessary to solve bulk Hg speciation, in both soil fractions <2 mm and <2 μm. The main Hg-species found in the soil samples were metacinnabar (β-HgS), cinnabar (α-HgS), corderoite (Hg3S2Cl2), and an amorphous phase containing Hg bound to chlorine and sulfur. The amount of metacinnabar and amorphous phases increased in the fraction <2 μm. No interaction among Hg-species and soil components was observed. All the observed Hg-species originated from the slow weathering of an inert Hg-containing waste material (K106, U.S. EPA) dumped in the area several years ago, which is changing into a relatively more dangerous source of pollution.  相似文献   
105.
The risk assessment of pesticides on soil fauna is an issue to protect agroecosystem sustainability. Enchytraeids are recognized as relevant soil bioindicators of chemical stress in agroecosystems. In laboratory, the reproduction test was found to be sensitive to reveal chemical impacts on enchytraeids. However, it does not allow to assess the impacts on ecological functions in which enchytraeids are involved. The objectives of this study were (i) to explore the feasibility of the bait-lamina test with enchytraeids under laboratory conditions and (ii) to compare its sensitivity with the Enchytraeid Reproduction Test. We exposed individuals of Enchytraeus albidus to two commercial formulations of fungicides widely used in Europe. The EC50 reproduction for the Swing® Gold (50 g L?1 epoxiconazole and 133 g L?1 dimoxystrobin) and the Cuprafor micro® (50% copper oxychloride) were respectively estimated at 1.66?±?0.93 times the recommended dose and >?496 mg kg?1 of copper. However, no impact was found on the feeding activity of enchytraeids. The bait-lamina test thus appeared less sensitive than the Enchytraeid Reproduction Test to the tested fungicides. Despite that, this test which is achievable under laboratory conditions and allows assessing indirect effects of pesticides is quick, cheap, and easy to perform. It would deserve to be used to explore longer-exposure effects through the repeated addition of bait-lamina sticks.  相似文献   
106.
107.

Background, aim and scope  

Polluted sediments in rivers may be transported by the river to the sea, spread over river banks and tidal marshes or managed, i.e. actively dredged and disposed of on land. Once sedimented on tidal marshes, alluvial areas or control flood areas, the polluted sediments enter semi-terrestrial ecosystems or agro-ecosystems and may pose a risk. Disposal of polluted dredged sediments on land may also lead to certain risks. Up to a few years ago, contaminated dredged sediments were placed in confined disposal facilities. The European policy encourages sediment valorisation and this will be a technological challenge for the near future. Currently, contaminated dredged sediments are often not valorisable due to their high content of contaminants and their consequent hazardous properties. In addition, it is generally admitted that treatment and re-use of heavily contaminated dredged sediments is not a cost-effective alternative to confined disposal. For contaminated sediments and associated disposal facilities used in the past, a realistic, low cost, safe, ecologically sound and sustainable management option is required. In this context, phytoremediation is proposed in the literature as a management option. The aim of this paper is to review the current knowledge on management, (phyto)remediation and associated risks in the particular case of sediments contaminated with organic and inorganic pollutants.  相似文献   
108.
Human perception of in-channel wood can influence decision-making about wood reintroduction in watercourses for restoration purposes. A questionnaire survey was conducted among first-year and advanced Polish students and professionals involved in the management and protection of watercourses in Poland. The purpose was to assess their perception of river scenes with and without wood in terms of naturalness, aesthetics, danger and need for improvement. Generally, students perceived riverscapes with wood to be less aesthetic, more dangerous and needing more improvement than riverscapes without wood. However, many aspects of the riverscape perception are subject to changes as the student progresses in studying. The culturally conditioned, negative perception of in-channel wood is reduced during the education of geography and biology students but enhanced in the course of water engineering studies. The improved perception of watercourses containing wood was most pronounced for the advanced geography students from a university in which some tutors conducted research on in-channel wood and could have transferred knowledge about and positive attitudes toward wood to their students. A comparison of the riverscape evaluation by biology students and national park managers indicates that education in the discipline facilitates understanding of the environmental significance of in-channel wood although its effects are highly insufficient to form the positive attitude toward wood-containing watercourses typical of the managers. In turn, the education of water engineering students about in-channel wood apparently dominantly emphasizes threats caused by its presence in watercourses, so that the students' highly negative attitude toward wood needs to be significantly moderated when the graduates begin working as water authority managers.  相似文献   
109.
The occurrence of organic micropollutants in ground- and surface waters has become an important concern for the drinking water industry, mainly because of possible related health effects. Due to the polar nature of some of these pollutants, they are not completely removed by traditional water treatment barriers. This paper offers an overview of priority organic micropollutants and their occurrence in Flemish and Dutch water sources. Furthermore, rejection by nanofiltration is qualitatively predicted for the selected priority micropollutants. The qualitative prediction is based on the values of key solute and membrane parameters in nanofiltration. Predicted values are then compared with experimental values obtained from literature. Overall, the qualitative predictions are roughly in agreement with literature values. Prediction based on key parameters may thus prove to be a very quick and useful technique to assess the implementation of nanofiltration as a treatment step for organic micropollutants in drinking water plant design.  相似文献   
110.
Redox reactions in the Fe-As-O2 system   总被引:1,自引:0,他引:1  
Johnston RB  Singer PC 《Chemosphere》2007,69(4):517-525
We have examined two redox reactions involving arsenic and iron at near-neutral pH: the reduction of As(V) by Fe(II) under anoxic conditions, and the co-oxidation of As(III) during Fe(II) oxygenation. We also considered the impact of goethite, pH buffers, and radical scavengers on these reactions. In a series of anoxic experiments, Fe(II) was found to reduce As(V) in the presence of goethite, but not in homogeneous solution. The reaction rate increased with increasing pH and Fe(II) concentration, but in all cases was relatively slow. In aerobic experiments, the kinetics of Fe(II) oxygenation at neutral pH, and the corresponding oxidation of As(III) were found to depend heavily on pH buffer type and concentration. The classic formulation of Fe(II) oxidation by oxygen, involving four single-electron transfers, was reviewed and found to be inadequate for explaining observed oxidation of Fe(II) and As(III). Widely cited rate constants for Fe(II) oxygenation originate from experiments conducted in carbonate buffer, and do not match observations made in phosphate, MES, or HEPES systems. In phosphate buffer, Fe(II) oxidation is rapid and dependent on phosphate concentration. In MES and HEPES buffers, Fe(II) oxidation is much slower due to the lack of labile ferrous iron species. Oxygenation of Fe(II) appears to proceed through different mechanisms in phosphate and MES or HEPES systems. In both cases, reactive intermediary species are produced which can oxidize As(III). These oxidants are not the hydroxyl radical, but may be Fe(IV) species.  相似文献   
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