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101.
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PROBLEM: Fresh market berry production workers are exposed to physical risk factors for musculoskeletal injury. METHOD: We disseminated information through trade publications and other sources to berry managers in seven U.S. states about five prevention through design practices that were both safer and more profitable than traditional methods. We administered mail evaluation questionnaires prior to the intervention and after each of four intervention years to rolling, independent U.S. samples and to comparison New Zealand berry farm manager samples after years one through three. RESULTS: U.S. manager self-reports of reading trade publication information increased compared to baseline values for two of five practices and self-reported awareness increased for four of five practices. There were no increases in adoption. More U.S. than New Zealand managers reported getting information about two practices from trade publications and about four practices from public events. No U.S. versus New Zealand differences were observed in reported awareness or adoption for any practice. IMPACT ON INDUSTRY: This study showed that even a modest campaign can build awareness of safer practices fairly quickly in three to four years among small agricultural firms but that increasing adoption apparently requires more time. Widespread adoption of safer practices could help keep operators in business longer as they age by reducing the workload and musculoskeletal strain associated with labor intensive crop production for them and their workforce. Adoption of practices that also improve profits, like the five practices featured in this study, could also help managers stay in business.  相似文献   
103.
An increasing trend towards the use of sustainable processes has led to recycled materials being incorporated into concrete. It is generally recognised that crushed recycled construction aggregate material produces concrete of a lower compressive strength, when used as an aggregate replacement due to deleterious materials within the aggregate.It is generally accepted that in the UK, freeze/thaw attack is, after chloride-induced corrosion, the most common cause of concrete deterioration. This paper addresses the freeze/thaw durability of recycled aggregate concrete using a paired comparison test based upon weight loss and final compressive strength.Recycled aggregate concrete was found to be of at least equal durability to concrete manufactured with virgin aggregates. This was due to careful selection of the replacement aggregate and treatment prior to batching.Durability is an important material property and recycled aggregates need to be widely tested to gain confidence for use within the industry and this work shows future possibilities.  相似文献   
104.
A study of acute respiratory illness was conducted from November 1968 through April 1969 among families residing in an area of relatively high nitrogen dioxide exposure, in an area of elevated suspended particulate exposure, and in two control areas of Greater Chattanooga. Respiratory illness rates were consistently higher in all family segments in the high-nitrogen dioxide exposure area when rates were averaged for the entire 24 weeks of study, the A2/Hong-Kong epidemic period, or post-epidemic interval. A relative excess in respiratory illness of 18.8 percent was found among families exposed to elevated NO2 concentrations and an excess of 10.4 percent was found among families in the elevated-suspended particulate exposure area.  相似文献   
105.
The effects of viewing different types of information were investigated in people judging the social acceptability of alternative forest harvest systems. Approximately 500 Tasmanians were shown still-simulated images of four harvest systems (a clearfell system, two aggregated retention systems, and a selective system) and were asked to judge their acceptability. Individual interviews were conducted with 12 of the participants. It was anticipated that people holding different beliefs about the consequences of harvesting would have different responses to information. Cluster analysis was used to group participants according to these beliefs. Responses to still images were compared with responses to two other types of information: information about consequences of the harvest systems in the form of indicator symbols, and information about regeneration over time, presented as visual animations. The effects of information differed across both harvest system and belief cluster groups of participants. The largest effects of information occurred in people who held a mix of beliefs about consequences. Within this group, participants who viewed the indicators rated a 30% aggregated retention system higher and selective harvesting lower, than those who did not view the indicators. Viewing animated sequences led to slightly higher ratings of the more intensive harvest systems and significantly lower ratings of the selective harvest system than those based on the still images. The interview data provided examples of interviewees viewing information critically against their own values and beliefs. Only some interviewees appeared to use it in judging social acceptability  相似文献   
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Effectively addressing the health risks of climate change necessitates an active crosssectoral approach because health risks arise predominantly via sectors such as water, agriculture and energy. Much has been written on climate change and its impact on health, but little attention has focused on the realpolitik of how to progress the development and implementation of health-relevant strategies and policies to reduce this impact. The objective of this paper is to propose three solutions to address current deficiencies: i) strengthening the capacity and understanding of health officials in relation to climate change and health; ii) improving cross-sectoral partnerships with sectors relevant to climate change and health, and iii) identifying organisations influential in the development of climate change mitigation and adaptation strategies and policies, with a view to better target advocacy efforts. Practical examples of each solution are provided. In conclusion, as a steward of public health, the health sector must take the initiative to encourage a cross-sectoral approach that includes capacity development, coupled with an understanding of influential organisations. If this is done effectively, health, social and economic development goals can be reached more efficiently.  相似文献   
108.
The spatial and temporal variability of riverbed vertical hydraulic conductivity (K(v)) was investigated at a site of induced infiltration, associated with a municipal well field, to assess the impact of high-stage events on scour and subsequently the riverbed K(v). Such impacts are important when considering the potential loss of riverbank filtration capacity due to storm events. The study site, in and along the Great Miami River in southwest Ohio, overlaid a highly productive glacial-outwash aquifer. A three-layer model for this system was conceptualized: a top layer of transient sediment, a second layer comprising large sediment resistant to scour, but clogged with finer sediment (the armor/colmation layer), and a third layer that was transitional to the underlying higher-K(v) aquifer. One location was studied in detail to confirm and quantify the conceptual model. Methods included seepage meters, heat-flow modeling, grain-size analyses, laboratory permeameter tests, slug tests and the use of scour chains and pressure-load cells to directly measure the amount of sediment scour and re-deposition. Seepage meter measured riverbed K(v) ranged from 0.017 to 1.7 m/d with a geometric mean of 0.19 m/d. Heat-transport model-calibrated estimates were even lower, ranging from 0.0061 to 0.046 m/d with a mean of 0.017 m/d. The relatively low K(v) was indicative of the clogged armor layer. In contrast, slug tests in the underlying riverbed sediment yielded K(v) values an order of magnitude greater. There was a linear relationship between scour chain measured scour and event intensity with a maximum scour of only 0.098 m. Load-cell pressure sensor data over a 7-month period indicated a total sediment-height fluctuation of 0.42 m and a maximum storm-event scour of 0.28 m. Scour data indicated that the assumed armor/colmation layer almost always remained intact. Based on measured layer conductivities and thicknesses, the overall K(v) of this conceptualized system was 1.6 m/d. Sensitivity analyses indicated that even complete scour of the armor/colmation layer would likely increase the overall K(v) only by a factor of 1.5. Most scour events observed removed only the transient sediment, having very little effect on the entire system indicating low risk of losing filtration capacity during storms. The research, however, focused on the point bar, depositional side of the river. More research of the entire river profile is necessary.  相似文献   
109.
CO2 capture and storage has gained widespread attention as an option for reducing greenhouse gas emissions. Chemical absorption and stripping of CO2 with hot potassium carbonate (K2CO3) solutions has been used in the past, however potassium carbonate solutions have a low CO2 absorption efficiency. Various techniques can be used to improve the absorption efficiency of this system with one option being the addition of promoters to the solvent and another option being an improvement in the mass transfer efficiency of the equipment. This study has focused on improving the efficiency of the packed column by replacing traditional packings with newer types of packing which have been shown to have enhanced mass transfer performance. Three different packings (Super Mini Rings (SMRs), Pall Rings and Mellapak) have been studied under atmospheric conditions in a laboratory scale column for CO2 absorption using a 30 wt% K2CO3 solution. It was found that SMR packing resulted in a mass transfer coefficient approximately 20% and 30% higher than that of Mellapak and Pall Rings, respectively. Therefore, the height of packed column with SMR packing would be substantially lower than with Pall Rings or Mellapak. Meanwhile, the pressure drop using SMR was comparable to other packings while the gas flooding velocity was higher when the liquid load was above 25 kg m−2 s−1. Correlations for predicting flooding gas velocities and pressure drop were fitted to the experimental data, allowing the relevant parameters to be estimated for use in later design.  相似文献   
110.
Ulvaria obscura, a prominent component of green tide blooms in Washington, is unique among macroalgae because it contains dopamine. To examine dopamine release by U. obscura following simulated low tides, we conducted 6 field experiments in which algae were emersed for 75 min and then immersed in filtered seawater (FSW). Dopamine was measured in algal tissues prior to emersion and 3 h after immersion and in seawater for 3 h following immersion. In our experiments, algae released 7–100% of their tissue dopamine, resulting in average seawater concentrations of 3–563 μM. In 5 of 6 experiments, seawater dopamine concentrations were highest immediately after immersion, and then decreased over time. The percentages of dopamine released were not correlated with tissue dopamine concentrations, but were positively correlated with solar radiation during emersion. The release of dopamine, which is both cytotoxic and genotoxic, may explain the negative effects of U. obscura exudates on marine organisms.  相似文献   
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