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261.
262.
The failure to anticipate the public's response to environmental problems can lead to expensive delays, bad public relations, and litigation, as well as environmental decisions that do not represent public values and preferences. This study examines the influence of conflict between management goals, perceived resource scarcity, and information bias on evaluations of the importance of management goals; the perception of conflicts among the goals; and the emotions evoked in an urban forest management problem. Environmental problem scenarios were systematically manipulated as to the level of conflict between development and natural preservation goals, the scarcity of urban nature, and the bias of the presented information. Evaluations of the importance of urban nature and economic development were susceptible to manipulations of scarcity. The importance of urban nature was also higher when information was biased toward pro-preservation issues. Negative emotions were associated with high conflict and scarcity and with the propreservation information bias. Both evaluations of goal importance and conflict among goals appeared to be based on an underlying economics-versus-amenity dimension. These results are similar to previous studies of environmental decision making with regard to nonurban environmental problems. This research offers a beginning in understanding and anticipating the way members of the public may respond to information about environmental problems. 相似文献
263.
The Canadian province of British Columbia (BC) is taking significant steps towards climate change mitigation, including a carbon tax on fossil fuels and legislation that mandates greenhouse gas (GHG) reductions within public sector organisations and GHG reduction targets for municipalities. This paper carries out a preliminary scan of the GHG emissions of BC communities using the provincially mandated Community Energy and Emissions Inventory reports. We map trends in energy consumption and emissions per capita while uncovering correlations between these variables and land-use planning, geographic, and demographic variables. These data have shown that: (1) energy consumption in BC is an adequate proxy for GHG emissions; (2) transportation, more than buildings, is a strong driver of overall GHG emissions; (3) building emissions are not likely to be strongly influenced by dwelling type, but density of buildings is crucial; (4) geographic location influences emissions; and (5) population size and age do not appear to influence per capita emissions. These findings are particularly important as they suggest that the potentially intransigent factors of income and population size need not be barriers to achieving significant GHG reductions. The policy onus thus falls squarely on transportation planning, land-use, energy conservation, and fuel switching. This in turn highlights the importance of deeper underlying sociocultural and political preferences, which shape the behaviours that have a strong bearing on emissions profiles. 相似文献
264.
Herbert C. McKee 《Journal of the Air & Waste Management Association (1995)》2013,63(3):271-272
Under Title III of SARA, companies must provide information about chemicals that they manufacture, store, or process. Communities will use data about potential accidental releases to develop local emergency plans. Data about routine chemical releases will be made available to the public on a computer data base. Simply having such data available does not ensure consensus about reducing potential chemical risks. Laboratory and field research are summarized, indicating that people tend to edit small risks to zero as being too small to worry about, or to adjust them imperfectly from an anchor equal to the potential loss. These results suggest recommendations for communicating about the risks posed by accidental or routine releases of chemicals. 相似文献
265.
266.
Modeling Phosphate Influence on Arsenate Reduction Kinetics by a Freshwater Cyanobacterium 总被引:1,自引:0,他引:1
Arsenic speciation in natural surface-water systems can be highly impacted through biological processes that result in non-thermodynamically
predicted species to dominate the system. In laboratory experiments, arsenate reduction by a freshwater cyanobacterium exhibited
saturation kinetics increasingly inhibited by elevating solution phosphate concentrations. Approximately 100% arsenate reduction
occurred by days 4, 7, and 10 in the low (0.35 μm), middle (3.5 μm), and high (35 μm) phosphate treatments, respectively,
with maximum arsenate reduction rates ranged from 0.013 μmol As g C−1 day−1 in the high-phosphate treatment to 0.398 μmol As g C−1 day−1 in the low-phosphate treatment. Saturation kinetic models were utilized to evaluate the impact of cell growth and arsenate-phosphate
uptake competition on arsenate reduction rates by the cyanobacterium. Results showed reduced arsenicals dominate arsenic speciation
once growth reached steady state, indicating reduced arsenicals may dominate natural systems, even when considering conservatively
high, abiotic arsenic reoxidation. 相似文献
267.
Herbert C. McKee John H. Margeson Thomas W. Stanley 《Journal of the Air & Waste Management Association (1995)》2013,63(10):870-875
The Methods Standardization Branch of the Environmental Protection Agency, National Environmental Research Center, has undertaken a program to standardize methods used in measuring air pollutants covered by the national primary and secondary air quality standards. This paper presents the results of a collaborative test of the method specified for carbon monoxide. The test involved analysis of CO in air samples (in cylinders) by participating laboratories. Three concentrations, covering the range of the method which is, 0 to 58 mg/m3, were analyzed dry and humidified on each of three days by 15 collaborators. The method of analysis, nondispersive infrared spectrometry (NDIR), involved an NDIR instrument in combination with different procedures for eliminating water vapor interference. A statistical analysis of the data obtained produced the following results: 1. The checking limit for duplicates (replication error) is 0.5 mg/m3. 2. The repeatability (variation within a laboratory) is 1.6 mg/m3. 3. The reproducibility (variation between laboratories) varies nonlinearly with concentration; i.e., a minimum of 2.3 mg/m3 at a concentration of 20 mg/m3 and ranges as high as 4.3 mg/m3 in the concentration range of 0 to 58 mg/m3. 4. The reproducibility at the level of the national primary ambient air quality standard, 10 mg/m3-8-hour average, is 2.5 mg/m3 or 25%. 5. The minimum detectable sensitivity is estimated to be 0.3 mg/m3. 6. Compensation for water vapor interference is satisfactorily accomplished using drying agents and refrigeration methods. The use of narrow-band optical filters alone may not provide adequate compensation. 7. The accuracy obtained depends upon the availability of reliable calibration gases. Based on the results of this study, the method produces results that average 2.5% high. Future papers will contain test results for methods to measure other air pollutants. 相似文献
268.
Herbert C. McKee 《Journal of the Air & Waste Management Association (1995)》2013,63(2):124-128
A collaborative test was conducted to determine the precision of the chemiluminescent method which has been specified for measuring ozone, to determine photochemical oxidant. Ten laboratories participated in a test involving the analysis of an urban atmosphere containing a photochemical smog mixture. Ozone generators were used to increase the O3 level over that naturally occurring, in order to cover an adequate range of concentrations. The range tested was 0 to 0.5 ppm. A statistical analysis of the data obtained was used to derive equations for within laboratory and between laboratory standard deviations. In order to evaluate sampling data, these equations can be used in various statistical procedures to estimate repeatability, reproducibility, lower detectable limit, and other measures that establish the precision of the method. Using specific definitions for repeatability and reproducibility, the following approximate estimates were obtained in the range of zero to 0.5 ppm: Repeatability—0.01 to 0.04 ppm (varies with concentration, linear). Reproducibility—0.01 to 0.09 ppm (varies with concentration, non-linear). The lower detectable limit depends on instrumental and other variables, and cannot be specified precisely. Under typical assumptions, this limit can be estimated at between 0.006 and 0.009 ppm. 相似文献
269.
Herbert Inhaber 《Journal of the Air & Waste Management Association (1995)》2013,63(6):808-814
The 17th annual Government Affairs Seminar of the Air & Waste Management Association was held March 16-17,1989 in Washington, DC. The overall theme was "Environmental Challenges of the 1990s," and included among the challenges were two issues in waste management: managing municipal waste and paying for cleanup. Summaries of the remarks of four panelists appear on the following pages. 相似文献
270.
Anhydrosugars, such as levoglucosan and its isomers (mannosan, galactosan), as well as the solvent-extractable lignin phenols (methoxylated phenols) are thermal degradation products of cellulose/hemicellulose and lignin, respectively. These two groups of biomarkers are often used as unique tracers of combusted biomass inputs in diverse environmental media. However, detailed characterization of the relative proportion and signatures of these compounds in highly heterogeneous plant-derived chars are still scarce. Here we conducted a systematic study to investigate the yields of solvent-extractable anhydrosugars and lignin phenols in 25 lab-made chars produced from different plant materials under different combustion conditions. Solvent-extractable anhydrosugars and lignin phenols were only observed in chars formed below 350 °C and yields were variable across different combustion temperatures. The yields of mannosan (M) and galactosan (G) decreased more rapidly than those of levoglucosan (L) under increasing combustion severity (temperature and duration), resulting in variable L/M and L/(M + G) ratios, two diagnostic ratios often used for identification of combustion sources (e.g. hardwoods vs. softwoods vs. grasses). Our observations thus may provide an explanation for the wide ranges of values reported in the literature for these two ratios. On the other hand, the results of this study suggest that the ratios of the major solvent-extractable lignin phenols (vanillyls (V), syringyls (S), cinnamyls (C)) provide additional source reconstruction potential despite observed variations with combustion temperature. We thus propose using a property-property plot (L/M vs. S/V) as an improved means for source characterization of biomass combustion residues. The L/M-S/V plot has shown to be effective in environmental samples (soil organic matter, atmospheric aerosols) receiving substantial inputs of biomass combustion residues. 相似文献