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391.
ABSTRACT: Municipalities typically seek additional water supplies whenever prospective population and economic growth suggests the inadequacy of currently available water supply. The benefit of supply enhancement is usually construed as avoiding debilitating water scarcity. A more effective approach to planning is to compare the benefits and costs of supply augmentation. The net present value of benefits for a supply increase in a representative Texas community is calculated for alternative scenarios relating to population growth, rate growth, and the temporal distribution of the increased supply. Consumer surplus measures are sensitive to all three of these factors and vary from $0 to over $4000 per acre-foot. A notable finding is that the added supply may offer zero values in cases where real water prices increase at an annualized rate of 4 percent (or greater) which is half the rate occurring in Texas from 1981–1985.  相似文献   
392.
The following article is an attempt to reconcile the opinions of various activist-oriented non-governmental organizations (NGOs) on the use of gender analysis as a policy tool in the field of international development and macroeconomic policy. Of special concern to the author is the evolving relationship between international financial institutions (IFIs) and grassroots environmental NGOs seeking reform in macroeconomic policy initiation, implementation and evaluation. The ideas presented below are those of the author alone, and are solely intended to facilitate dialogue between the aforementioned parties as an alternative to the characteristic set of untenable demands and concomitant uncompromising resistance. Thus stated, the reader is challenged to remove his/her professional hat to accept or reject the validity of the propositions with an equal proportion of reason and intuition.  相似文献   
393.
Zur Verwendung von Mikroalgen für Ernährungszwecke   总被引:2,自引:0,他引:2  
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394.
The humic colloid borne Am(III) transport was investigated in column experiments for Gorleben groundwater/sand systems. It was found that the interaction of Am with humic colloids is kinetically controlled, which strongly influences the migration behavior of Am(III). These kinetic effects have to be taken into account for transport/speciation modeling. The kinetically controlled availability model (KICAM) was developed to describe actinide sorption and transport in laboratory batch and column experiments. Application of the KICAM requires a chemical transport/speciation code, which simultaneously models both kinetically controlled processes and equilibrium reactions. Therefore, the code K1D was developed as a flexible research code that allows the inclusion of kinetic data in addition to transport features and chemical equilibrium. This paper presents the verification of K1D and its application to model column experiments investigating unimpeded humic colloid borne Am migration. Parmeters for reactive transport simulations were determined for a Gorleben groundwater system of high humic colloid concentration (GoHy 2227). A single set of parameters was used to model a series of column experiments. Model results correspond well to experimental data for the unretarded humic borne Am breakthrough.  相似文献   
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Scientific debates on environmental impacts in cost-benefit analysis (CBA) focus on methodological questions. The literature, however, contains very little information on the influence of these debates on CBAs made in spatial planning practice. In this paper, this gap is filled by a qualitative analysis of 67 CBAs made in the Netherlands between 2000 and 2011. From the literature on environmental valuation, we derive criteria to evaluate the quality of CBA practice, such as completeness and the inclusion of uncertainties. The analysis shows that in many cases relevant environmental effects are omitted or not monetised. Moreover, non-monetised effects are often not included in CBA conclusions. If impacts are monetised, the methods used are frequently not very sophisticated. The consequences of assumptions are often not communicated, for example, where high discount rates make long-term effects seem unimportant. In this research we identify four main points for good practice.  相似文献   
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OBJECTIVE: Smoking has been linked to disease and injury. The purpose of this study is to investigate the smoking habits of motor vehicular driver trauma center patients and their association with previous injury history and risky behaviors. METHODS: The studied population included 323 motor vehicular driver injury patients (123 smokers and 200 non-smokers) interviewed as part of a larger study of psychoactive substance use disorders at an adult Level I trauma center. Patients with head injuries, hospital stays of less than two days, and diminished cognition were excluded. Interviews included demographics (age, gender, race, marital status), socioeconomic status (SES; income, education, employment), risky behaviors (seatbelt non-use, drinking and driving, riding with drunk driver, binge drinking), and trauma history information (vehicular, assault, and other injuries). Substance abuse (alcohol and drug dependence) was evaluated in depth using DSM III-R criteria. Smokers and non-smokers were compared in relation to control and dependent variables using student's t test and chi-square (alpha = 0.05). Outcome variables included previous trauma history and risky behaviors. Multiple logistic regression models using step-down selection methods (alpha = 0.05) were constructed with risky behaviors and trauma history as dependent variables including demographics, SES and substance as independent variables. RESULTS: Smokers represented 38 percent of the 323 patients studied. Smokers (n = 123) were younger (34 vs. 43 years), more likely to be male (72 percent vs. 50 percent), not married (72 percent vs. 56 percent), and had higher rates of alcohol (29 percent vs. 9 percent) and drug dependence (14 percent vs. 3 percent) than non-smokers (n = 200). Educational achievement (20 percent vs. 15 percent less than high school) and income level (24 percent vs. 23 percent with less than $15,000 of yearly income) were not different between smokers and non-smokers. Smokers were more likely than non-smokers to have a history of prior vehicular trauma (48 percent vs. 26 percent), assault (25 percent vs. 9 percent), or other injury (50 percent vs 37 percent). The following injury-prone behaviors were also more common among the smokers than non-smokers: seatbelt non-use (49 percent vs. 29 percent), drinking and driving (38 percent vs. 15 percent), riding with drunk driver (38 percent vs. 13 percent), and binge drinking (68 percent vs. 26 percent). In multiple logistic regression models adjusting for demographics, SES, and substance abuse, smoking revealed significantly higher odds ratios (OR) for the following dependent variables: seatbelt non-use (OR = 2.9), riding with drunk driver (OR = 2.2), binge drinking (OR = 2.4), previous vehicular (OR = 2.0), and assault injuries (OR = 2.5). Smoking did not reach significance for drinking and driving and other (non-vehicular and non-assault) injury. CONCLUSION: Smoking is independently associated with risky behaviors and repeated history of vehicular or assault injury within the vehicular trauma population.  相似文献   
400.
The application of direct-flame incineration to successfully eliminate a smoke-oil-mist and odor problem in the manufacture of rubber-base rug underlay, is presented. The investigation of various air pollution control processes leading to the development and adoption of the direct-flame incineration system, is covered. The rug-underlay curing process incorporating the direct-flame incineration system with primary heat recovery is described. Results and discussion of a source test to determine the effectiveness of direct-flame incineration in this application are included.  相似文献   
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