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61.
Ninety-five white-collar workers employed by an insurance company using visual display units (VDU) connected by telecommunication to a central computer filled in a questionnaire concerning psychosocial stressors in connection with work at the VDU. Eleven persons with extensive and ten with no work at VDUs were also studied during regular work, during breakdown of machinery, and in their leisure time. Self-reports on mood and alertness were recorded along with blood pressure, heart rate, and excretion of adrenaline and noradrenaline. Results indicate that (1) stress and mental strain occurred in association with delayed response times in the computer system and unpredicted interruptions of system operation, (2) such a temporary interruption caused an increase of blood pressure and adrenaline excretion, (3) complaints of stress and strain were repotted mainly by data-entry staff, (4) data-entry groups displayed a higher level of physiological arousal during post-work hours than a control group, and (5) that a majority of those who worked continuously at a VOU reported physical discomfort within 1.5 hours. It is concluded that stress and strain in computerized work may be counteracted at the technological and the organizational level: by reducing the duration and frequency of breakdowns, by reducing response times in the system, and by eliminating pure data-entry tasks.  相似文献   
62.
Our interest is in electricity demand and the temperature aspects of climate change. Electricity consumption is of interest both from the perspectives of adaptation to climate change and emission reductions. We study the relationship between European electricity consumption and outdoor temperature and other variables, using a panel data set of 31 countries. Apart from providing a rare quantitative window into adaptation, the study contributes demand system parameters with respect to price and income. The results suggest that weather has a statistically significant effect on electricity demand, with effects that are of plausible magnitude. In a simulation of climate change for the next 100 years—other factors held constant—we find that the demand for heating will decrease in Northern Europe while the demand for cooling will increase in Southern Europe. In countries like Cyprus, Greece, Italy, Malta, Spain, and Turkey the net effect of increased cooling outweighs decreased heating consumption whereas in most of Europe the opposite holds. The largest estimated partial impact is 20%, which predicted increase in adaptive consumption for Turkey and decrease in adaptive consumption for Latvia. Estimated elasticities with respect to income and price are 0.8 and minus 0.2 respectively: plausible in the light of the literature. As a discussion item, we add that electricity consumption changes due to temperature change likely will be small compared to those due to other factors, such as changes in income, demography and technology. The study does not include effects of climate change other than through electricity consumption.  相似文献   
63.
64.
In order to carry out efficient traffic and air quality management, validated models and PM emission estimates are needed. This paper compares current available emission factor estimates for PM10 and PM2.5 from emission databases and different emission models, and validates these against eight high quality street pollution measurements in Denmark, Sweden, Germany, Finland and Austria.The data sets show large variation of the PM concentration and emission factors with season and with location. Consistently at all roads the PM10 and PM2.5 emission factors are lower in the summer month than the rest of the year. For example, PM10 emission factors are in average 5–45% lower during the month 6–10 compared to the annual average.The range of observed total emission factors (including non-exhaust emissions) for the different sites during summer conditions are 80–130 mg km−1 for PM10, 30–60 mg km−1 for PM2.5 and 20–50 mg km−1 for the exhaust emissions.We present two different strategies regarding modelling of PM emissions: (1) For Nordic conditions with strong seasonal variations due to studded tyres and the use of sand/salt as anti-skid treatment a time varying emission model is needed. An empirical model accounting for these Nordic conditions was previously developed in Sweden. (2) For other roads with a less pronounced seasonal variation (e.g. in Denmark, Germany, Austria) methods using a constant emission factor maybe appropriate. Two models are presented here.Further, we apply the different emission models to data sets outside the original countries. For example, we apply the “Swedish” model for two streets without studded tyre usage and the “German” model for Nordic data sets. The “Swedish” empirical model performs best for streets with studded tyre use, but was not able to improve the correlation versus measurements in comparison to using constant emission factors for the Danish side. The “German” method performed well for the streets without clear seasonal variation and reproduces the summer conditions for streets with pronounced seasonal variation. However, the seasonal variation of PM emission factors can be important even for countries not using studded tyres, e.g. in areas with cold weather and snow events using sand and de-icing materials. Here a constant emission factor probably will under-estimate the 90-percentiles and therefore a time varying emission model need to be used or developed for such areas.All emission factor models consistently indicate that a large part (about 50–85% depending on the location) of the total PM10 emissions originates from non-exhaust emissions. This implies that reduction measures for the exhaust part of the vehicle emissions will only have a limited effect on ambient PM10 levels.  相似文献   
65.
A method for determination of the climate gases CH4, CO2 and N2O in air samples and soil atmosphere was developed using GC-MS. The method uses straightforward gas chromatography (separation of the gases) with a mass spectrometric detector in single ion mode (specific determination). The gases were determined with high sensitivity and high sample throughput (18 samples h(-1)). The LOD (3sigma) for the gases were 0.10 micro L L(-1) for CH4, 20 microL L(-1) for CO2 and 0.02 microL L(-1) for N2O. The linear range (R2 = 0.999) was up to 500 microL L(-1) for CH4, 4000 microL L(-1) for CO2 and 80 microL L(-1) for N2O. The samples were collected in 10 mL vials and a 5 microL aliquot was injected on column. The method was tested against certified gas references, the analytical data gave an accuracy within +/-5% and a precision of +/-3%. The presence of < or = 10% by volume of C2H2 (often used experimentally to prevent N2 formation from N2O) did not interfere with detection for the targeted trace gases.  相似文献   
66.
67.
Objective: Standard deviation of lateral position (SDLP) is often the primary outcome in experimental studies on impaired driving. However, other measures may be easier and more practical to obtain and reflect a broader range of driving-related behaviors. We wanted to assess the validity and sensitivity of a range of measures in a driving simulator as well as during real driving and compare these to SDLP.

Methods: Twenty healthy male volunteers undertook 6 driving trials each, 3 in a regular car on a closed track resembling rural road conditions and 3 in a simulator with an identical driving scenario. Ethanol was used as impairing substance due to its well-characterized effects on driving. The subjects were tested sober and at blood alcohol concentrations (BAC) of approximately 0.5 and 0.9 g/L. We explored dose–response relationships between BAC and a range of driving-related measures, as well as their BAC-dependent effect sizes.

Results: In simulator driving, ethanol intake increased steering wheel reversal frequency, steering wheel movement measures, average speed, standard deviation of speed, and pedal use frequency. At the test track, only steering wheel movement and standard deviation of speed were significantly correlated to BAC. Likewise, reaction to unexpected incidents and observance of red traffic lights were adversely affected by ethanol in the simulator but not at the test track. Whereas SDLP showed a relatively large effect size that was similar in simulated and real driving, all other measures demonstrated smaller effect sizes, with less pronounced BAC effects on the test track than in the simulator.

Conclusions: The results suggest that the driving-related measures explored in this study are less sensitive to alcohol-mediated driving impairment than SDLP, especially during real (test track) driving. The discrepancy in effect sizes between simulated and real driving may imply low external validity of these measures in simulator studies.  相似文献   

68.
Objectives: The objective of this article is to assess the status of road safety in Asia and present accident and injury prevention strategies based on global road safety improvement experiences and discuss the way forward by indicating opportunities and countermeasures that could be implemented to achieve a new level of safety in Asia.

Methods: This study provides a review and analyses of data in the literature, including from the World Health Organization (WHO) and World Bank, and a review of lessons learned from best practices in high-income countries. In addition, an estimation of costs due to road transport injuries in Asia and review of future trends in road transport is provided.

Results: Data on the global and Asian road safety problem and status of prevention strategies in Asia as well as recommendations for future actions are discussed. The total number of deaths due to road accidents in the 24 Asian countries, encompassing 56% of the total world population, is 750,000 per year (statistics 2010). The total number of injuries is more than 50 million, of which 12% are hospital admissions. The loss to the economy in the 24 Asian countries is estimated to around US$800 billion or 3.6% of the gross domestic product (GDP).

Conclusions: This article clearly shows that road safety is causing large problems and high costs in Asia, with an enormous impact on the well-being of people, economy, and productivity. In many Asian low- and middle-income countries, the yearly number of fatalities and injuries is increasing. Vulnerable road users (pedestrians, cyclists, and motorcyclists combined) are particularly at risk. Road safety in Asia should be given rightful attention, including taking powerful, effective actions. This review stresses the need for reliable accident data, because there is considerable underreporting in the official statistics. Reliable accident data are imperative to determine evidence-based intervention strategies and monitor the success of these interventions and analyses. On the other hand, lack of good high-quality accident data should not be an excuse to postpone interventions. There are many opportunities for evidence-based transport safety improvements, including measures concerning the 5 key risk factors: speed, drunk driving, not wearing motorcycle helmets, not wearing seat belts, and not using child restraints in cars, as specified in the Decade of Action for Road Safety 2011–2020. In this commentary, a number of additional measures are proposed that are not covered in the Decade of Action Plan. These new measures include separate roads or lanes for pedestrians and cyclists; helmet wearing for e-bike riders; special attention to elderly persons in public transportation; introduction of emerging collision avoidance technologies, in particular automatic emergency braking (AEB) and alcohol locks; improved truck safety focusing on the other road user (including blind spot detection technology; underride protection at the front, rear, and side; and energy-absorbing fronts); and improvements in motorcycle safety concerning protective clothing, requirements for advanced braking systems, improved visibility of motorcycles by using daytime running lights, and better guardrails.  相似文献   

69.

Problem

Workers' motivation to actively take part in improvements to the work environment is assumed to be important for the efficiency of investments for that purpose. That gives rise to the need for a tool to measure this motivation.

Method

A questionnaire to measure motivation for improvements to the work environment has been designed. Internal consistency and test-retest reliability of the domains of the questionnaire have been measured, and the factorial structure has been explored, from the answers of 113 employees.

Results

The internal consistency is high (0.94), as well as the correlation for the total score (0.84). Three factors are identified accounting for 61.6% of the total variance.

Discussion

The questionnaire can be a useful tool in improving intervention methods.

Impact on Industry

The expectation is that the tool can be useful, particularly with the aim of improving efficiency of companies' investments for work environment improvements.  相似文献   
70.
Novel communities will be formed as species with a variety of dispersal abilities and environmental tolerances respond individually to climate change. Thus, models projecting future species distributions must account for species interactions and differential dispersal abilities. We developed a species distribution model for Arctic char Salvelinus alpinus, a freshwater fish that is sensitive both to warm temperatures and to species interactions. A logistic regression model using lake area, mean annual air temperature (1961–1990), pike Esox lucius and brown trout Salmo trutta occurrence correctly classified 95 % of 467 Swedish lakes. We predicted that Arctic char will lose 73 % of its range in Sweden by 2100. Predicted extinctions could be attributed both to simulated temperature increases and to projected pike invasions. The Swedish mountains will continue to provide refugia for Arctic char in the future and should be the focus of conservation efforts for this highly valued fish.  相似文献   
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