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161.
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163.
Kenneth L. Heitner 《Journal of the Air & Waste Management Association (1995)》2013,63(12):1173-1177
This paper presents an overview on air pollution assessments of new fossil energy technologies for baseload electric generating plants. The discussion is oriented towards those who must understand the broad issues affecting the design and performance of such power plants. It is motivated by the potential air pollution problems caused by the near doubling of coal use projected for the next 15 years. The paper first reviews the applicable emissions performance standards for these plants, as well as predictions of likely future standards needed to protect the environment. The conclusion is reached that significantly tighter emissions standards will apply in the future. Next, the cost, emissions performance, and development status of the three major technology groups for coal fired baseload plants are reviewed. It is observed that while all of the technologies can meet the current standards, only the Baseline plant with Advanced Control Technology can meet future standards, without unreasonable increases in electrical generation costs. Furthermore, since Advanced Direct Combustion Technologies and Fuel Conversion Technologies are in very early stages of development, only the Baseline plant with Advanced Control Technology will be available to the utilities in the near term. This is because it will be evolved from the current commercial Baseline Technology. Hence, it is concluded that the utilities will use mainly the Baseline coal fired plant with Advanced Control Technology to protect the environment for the next 15-20 years. 相似文献
164.
Kenneth L. Tuttle David C. Junge 《Journal of the Air & Waste Management Association (1995)》2013,63(7):677-680
The emissions from combustion of wood residue fuel in an experimental spreader-stoker boiler were measured at the Fairplay Test Facility at Oregon State University. Stack gases were monitored to determine levels of excess air, opacity, and particulate loading. Particulate emissions were measured to determine the effects of underfire air flow rate and fuel bed depth on particulate carry over rate. An experiment conducted at four energy release rates and two fuel bed depths indicated that increased bed depth has the effect of reducing particulate emissions and that the effect increases as energy release rate increases. The experiment also showed increased energy release rate has the effect of increasing particulate emissions. The effects were found to be statistically significant. 相似文献
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166.
Jerry W. Crowder Kenneth J. Loudermilk 《Journal of the Air & Waste Management Association (1995)》2013,63(1):115-117
The body of information contained in this paper is directed to those individuals involved in the design and installation of air pollution control systems. When several sources are connected to one ventilation system, a critical part of the overall design is directed to assuring that the system is balanced so that the correct volume is exhausted from each point. The preferable technique for accomplishing this in industrial ventilation systems is the slide gate adjustment method, which can require extensive field adjustment to determine the final slide gate positions. In this study the pressure loss characteristics of slide gate dampers have been measured as a function of damper position, for both round and rectangular ductwork. Generalized graphs are presented that allow for the determination of damper position during the design phase, based on the amount of resistance that must be added to a given branch. Application of this technique indicates it to be both accurate and reliable and significantly reduces the time required to balance a system. 相似文献
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168.
Gilbert C. S. Lui W. K. Li Anders Bjørgesæter Kenneth M. Y. Leung 《Environmental science and pollution research international》2014,21(1):177-192
This paper describes a novel statistical approach to derive ecologically relevant sediment quality guidelines (SQGs) from field data using a nonparametric empirical Bayesian method (NEBM). We made use of the Norwegian Oil Industrial Association database and extracted concurrently obtained data on species density and contaminant levels in sediment samples collected between 1996 and 2001. In brief, effect concentrations (ECs) of each installation (i.e., oil platform) at a given reduction in species density were firstly derived by fitting a logistic-type regression function to the relationship between the species density and the corresponding concentration of a chemical of concern. The estimated ECs were further improved by the NEBM which incorporated information from other installations. The distribution of these improved ECs from all installations was determined nonparametrically by the kernel method, and then used to determine the hazardous concentration (HC) which can be directly linked to the species loss (or the species being protected) in the sediment. This method also enables an accurate estimation of the lower confidence limit of the HC, even when the number of observations was small. To illustrate the effectiveness of this novel technique, barium, cadmium, chromium, copper, mercury, lead, tetrahydrocannabinol, and zinc were chosen as example contaminants. This novel approach can generate ecologically sound SQGs for environmental risk assessment and cost-effectiveness analysis in sediment remediation or mud disposal projects, since sediment quality is closely linked to species density. 相似文献
169.
Marull Joan Cunfer Geoff Sylvester Kenneth Tello Enric 《Regional Environmental Change》2018,18(6):1765-1782
Regional Environmental Change - For better or worse, in those parts of the world with a widespread farming, livestock rising, and urban expansion, the maintenance of species richness and ecosystem... 相似文献
170.
Jun Yoshizaki Cavell Brownie Kenneth H. Pollock William A. Link 《Environmental and Ecological Statistics》2011,18(1):27-55
Misidentification of animals is potentially important when naturally existing features (natural tags) such as DNA fingerprints
(genetic tags) are used to identify individual animals. For example, when misidentification leads to multiple identities being
assigned to an animal, traditional estimators tend to overestimate population size. Accounting for misidentification in capture–recapture
models requires detailed understanding of the mechanism. Using genetic tags as an example, we outline a framework for modeling
the effect of misidentification in closed population studies when individual identification is based on natural tags that
are consistent over time (non-evolving natural tags). We first assume a single sample is obtained per animal for each capture
event, and then generalize to the case where multiple samples (such as hair or scat samples) are collected per animal per
capture occasion. We introduce methods for estimating population size and, using a simulation study, we show that our new
estimators perform well for cases with moderately high capture probabilities or high misidentification rates. In contrast,
conventional estimators can seriously overestimate population size when errors due to misidentification are ignored. 相似文献