全文获取类型
收费全文 | 132篇 |
免费 | 3篇 |
专业分类
安全科学 | 3篇 |
废物处理 | 8篇 |
环保管理 | 21篇 |
综合类 | 45篇 |
基础理论 | 20篇 |
污染及防治 | 29篇 |
评价与监测 | 3篇 |
社会与环境 | 6篇 |
出版年
2023年 | 1篇 |
2021年 | 4篇 |
2020年 | 2篇 |
2019年 | 1篇 |
2017年 | 4篇 |
2016年 | 3篇 |
2015年 | 6篇 |
2014年 | 4篇 |
2013年 | 7篇 |
2012年 | 8篇 |
2011年 | 9篇 |
2010年 | 2篇 |
2009年 | 6篇 |
2008年 | 6篇 |
2007年 | 7篇 |
2006年 | 9篇 |
2005年 | 3篇 |
2004年 | 3篇 |
2003年 | 6篇 |
2002年 | 4篇 |
2001年 | 6篇 |
2000年 | 1篇 |
1999年 | 5篇 |
1998年 | 3篇 |
1997年 | 1篇 |
1996年 | 1篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1992年 | 2篇 |
1991年 | 3篇 |
1989年 | 1篇 |
1987年 | 1篇 |
1986年 | 3篇 |
1981年 | 1篇 |
1971年 | 1篇 |
1968年 | 1篇 |
1964年 | 1篇 |
1959年 | 1篇 |
1954年 | 1篇 |
1926年 | 1篇 |
1925年 | 1篇 |
1924年 | 1篇 |
1923年 | 1篇 |
1922年 | 1篇 |
排序方式: 共有135条查询结果,搜索用时 31 毫秒
71.
In the management literature, heuristics are often conceived of as a source of systematic error, whereas logic and statistics are regarded as the sine qua non of good decision making. Yet, this view can be incorrect for decisions made under uncertainty, as opposed to risk. Research on fast and frugal heuristics shows that simple heuristics can be successful in complex, uncertain environments and also when and why this is the case. This article describes the conceptual framework of heuristics as adaptive decision strategies and connects it with the managerial literature. We review five classes of heuristics, analyze their common building blocks, and show how these are applied in managerial decision making. We conclude by highlighting some prominent opportunities for future research in the field. In the uncertain world of management, simple heuristics can lead to better and faster decisions than complex statistical procedures. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
72.
73.
Leat EH Bourgeon S Borgå K Strøm H Hanssen SA Gabrielsen GW Petersen A Olafsdottir K Magnusdottir E Fisk AT Ellis S Bustnes JO Furness RW 《Environmental pollution (Barking, Essex : 1987)》2011,159(5):1222-1228
Concentrations of POPs in Great skua eggs from Shetland are among the highest in North Atlantic seabirds, with up to 11,600 μg/kg (ww) DDE and up to 17,900 μg/kg ww ∑PCB. Concentrations of legacy POPs were significantly lower in 2008 than 1980. Decreases were greatest for least persistent compounds. Median ∑PBDEs increased from 99 μg/kg ww in 1980 to 173 μg/kg ww in 2008. There were changes in Great skua breeding season diet, with more adult Herring and Mackerel and less Sandeel. These changes increase exposure to POPs, since Herring and Mackerel accumulate more POPs than Sandeels. In both years, eggs with higher δ15N had higher POP concentrations. In 1980, birds feeding more on demersal discard fish from trawl fisheries and less on Sandeels, had higher POP levels in eggs. In 2008, individuals feeding more on Herring and Mackerel, and less on discards, had higher POP levels in eggs. 相似文献
74.
V. Blanes-Vidal M.N. Hansen A.P.S. Adamsen A. Feilberg S.O. Petersen B.B. Jensen 《Atmospheric environment (Oxford, England : 1994)》2009,43(18):3006-3014
The quality of rural life can be affected by offensive odors released from animal buildings and storage units. The objectives of this study were to compare the concentrations of odor and odorants above different types of stirred swine slurry to analyze the relationships between concentrations of odor (and odorants) and physicochemical characteristics of the slurry (i.e. pH, temperature, dry matter, volatile solids, and concentration of 22 chemical compounds); and to propose predictive models for the odor concentration (OC) based on these physicochemical characteristics (solely and in combination with concentrations of specific odorants in the air above the slurries). The study comprised data on concentrations of odor and odorants in the air above slurry samples (fresh and/or stored) collected from production units with farrowing sows, finishing swines, or weaning pigs at eight swine operations (N = 48). OC measured in the air above stirred swine slurry samples were not significantly different among production types or storage times. The physicochemical characteristics of the slurries were not useful for predicting OC or concentrations of hydrogen sulfide (or organic sulfides) above the slurry, but were related to concentrations of other emitted gases such as phenols and indoles (r2 = 0.65–0.79, p <0.05), ammonia (r2 = 0.86, p < 0.05) and carboxylic acids (r2 = 0.23–0.59, p <0.05). There was good precision of predictive models of OC based on selected slurry characteristics (i.e. pH, dry matter, nitrogen content, sulfur content or concentrations of individual aromatic compounds and carboxylic acids) together with concentrations of specific odorants in the air (e.g. hydrogen sulfide) (r2 between 0.70 and 0.92). This study suggests that predictive models could be useful for evaluating odor nuisance potentials of swine slurry during handling. 相似文献
75.
G. A. Petersen R. H. Sabersky 《Journal of the Air & Waste Management Association (1995)》2013,63(10):1028-1032
A series of experiments was conducted to determine the concentration of certain pollutants inside a car under typical driving conditions. The work was performed during the summer months in the Los Angeles area and measurements of O3, CO, NO, and NOx were taken. It was found that the O3 concentration in the passenger compartment may be maintained at relatively low values provided that the influx of outside air is limited. The low levels were explained by decay of O3 on surfaces within the compartment. The average concentration of the other components inside the car is about equal to that on the outside. In the current tests, however, the measured concentrations did not exceed any of the present standards. 相似文献
76.
David E. Abbey Gary L. Euler John K. Moore Floyd Petersen John E. Hodgkin Allan R. Magie 《Journal of the Air & Waste Management Association (1995)》2013,63(4):437-469
A method for setting air quality standards for long-term cumulative exposures of a population based on epidemiological studies has been developed. It uses exposure estimates interpolated from monitoring stations to zip code centroids, each month applied to zip code by month residence histories of the population. Two alternative cumulative exposure indices are used—hours in excess of a threshold, and the sum of concentrations above a threshold. The indices are then used with multiple logistic regression models for the health outcome data to form dose response curves for relative risk, adjusting for covariates. These curves are useful for determination of at what exposure amounts and threshold levels, effects which have both statistical and public health significance begin to occur. The method is applied to a ten year follow-up of a sub cohort of 7,343 members of the National Cancer Institute-funded Adventist Health Study. Up to 20 years of residence history was available. Analysis for prevalence of symptoms was conducted for four air pollutants— total oxidants, sulfur dioxide, nitrogen dioxide, and total suspended particulates. For each pollutant, cumulated exposures were calculated above each of five different thresholds. Statistically significant effects were noted for total suspended particulates, total oxidants, sulfur dioxide, past and passive smoking. 相似文献
77.
Solubilization, solution equilibria, and biodegradation of PAH's under thermophilic conditions 总被引:1,自引:0,他引:1
Biodegradation rates of PAHs are typically low at mesophilic conditions and it is believed that the kinetics of degradation is controlled by PAH solubility and mass transfer rates. Solubility tests were performed on phenanthrene, fluorene and fluoranthene at 20 degrees C, 40 degrees C and 60 degrees C and, as expected, a significant increase in the equilibrium solubility concentration and of the rate of dissolution of these polycyclic aromatic hydrocarbons (PAHs) was observed with increasing temperature. A first-order model was used to describe the PAH dissolution kinetics and the thermodynamic property changes associated with the dissolution process (enthalpy, entropy and Gibb's free energy of solution) were evaluated. Further, other relevant thermodynamic properties for these PAHs, including the activity coefficients at infinite dilution, Henry's law constants and octanol-water partition coefficients, were calculated in the temperature range 20-60 degrees C. In parallel with the dissolution studies, three thermophilic Geobacilli were isolated from compost that grew on phenanthrene at 60 degrees C and degraded the PAH more rapidly than other reported mesophiles. Our results show that while solubilization rates of PAHs are significantly enhanced at elevated temperatures, the biodegradation of PAHs under thermophilic conditions is likely mass transfer limited due to enhanced degradation rates. 相似文献
78.
Møhlenberg F Petersen S Petersen AH Gameiro C 《Environmental monitoring and assessment》2007,127(1-3):503-521
Nineteen years of monitoring data from the eutrophic Skive Fjord, Denmark were examined for linkages to external pressures
and drivers, including nutrient inputs, meteorology and stocks of blue mussels. Linkages were examined by: 1) time-series
analysis to document effects of nutrient reduction programs, 2) Pearson Rank correlations, 3) multivariate statistical analysis
(PLS) to identify water quality variables with high predictability and their linkages to pressures, and 4) regression analysis
to quantify relationships between pressures and water quality. Freshwater input, nitrogen load and phosphorus load showed
decreasing trends through the period 1984–2002. The load reductions were only partially translated into trends in water quality:
phosphorus decreased in most seasons, while total nitrogen decreased during winter and spring only. Phosphorus concentration
had the highest predictability (explained by seasonal temperature variation) followed by transparency, silicate, tot-N, chlorophyll-a,
primary productivity, phytoplankton diversity and phytoplankton turnover. The variation in pressures other than nutrient input
confounded the relations between loads and water quality. High biomass of mussels led to reduced chlorophyll-a and increased
transparency, while short-term variability in water column mixing led to changes in chlorophyll-a due to nutrient entrainment
and coupling to benthic mussels. 相似文献
79.
Jeanne L. Nel Dirk J. Roux Amanda Driver Liesl Hill Ashton C. Maherry Kate Snaddon Chantel R. Petersen Lindie B. Smith‐Adao Heidi Van Deventer Belinda Reyers 《Conservation biology》2016,30(1):176-188
Knowledge co‐production and boundary work offer planners a new frame for critically designing a social process that fosters collaborative implementation of resulting plans. Knowledge co‐production involves stakeholders from diverse knowledge systems working iteratively toward common vision and action. Boundary work is a means of creating permeable knowledge boundaries that satisfy the needs of multiple social groups while guarding the functional integrity of contributing knowledge systems. Resulting products are boundary objects of mutual interest that maintain coherence across all knowledge boundaries. We examined how knowledge co‐production and boundary work can bridge the gap between planning and implementation and promote cross‐sectoral cooperation. We applied these concepts to well‐established stages in regional conservation planning within a national scale conservation planning project aimed at identifying areas for conserving rivers and wetlands of South Africa and developing an institutional environment for promoting their conservation. Knowledge co‐production occurred iteratively over 4 years in interactive stake‐holder workshops that included co‐development of national freshwater conservation goals and spatial data on freshwater biodiversity and local conservation feasibility; translation of goals into quantitative inputs that were used in Marxan to select draft priority conservation areas; review of draft priority areas; and packaging of resulting map products into an atlas and implementation manual to promote application of the priority area maps in 37 different decision‐making contexts. Knowledge co‐production stimulated dialogue and negotiation and built capacity for multi‐scale implementation beyond the project. The resulting maps and information integrated diverse knowledge types of over 450 stakeholders and represented >1000 years of collective experience. The maps provided a consistent national source of information on priority conservation areas for rivers and wetlands and have been applied in 25 of the 37 use contexts since their launch just over 3 years ago. When framed as a knowledge co‐production process supported by boundary work, regional conservation plans can be developed into valuable boundary objects that offer a tangible tool for multi‐agency cooperation around conservation. Our work provides practical guidance for promoting uptake of conservation science and contributes to an evidence base on how conservation efforts can be improved. 相似文献
80.
Western North America is experiencing a dramatic expansion of piñon (Pinus spp.) and juniper (Juniperus spp.) (P-J) trees into shrub-steppe communities. Feature extracted data acquired from remotely sensed imagery can help managers rapidly and accurately assess this land cover change in order to manage rangeland ecosystems at a landscape-scale. The objectives of this study were to: (1) develop an effective and efficient method for accurately quantifying P-J tree canopy cover and density directly from high resolution photographs and (2) compare feature-extracted data to typical in-situ datasets used by land managers. Tree cover was extracted from aerial-photography using Feature Analyst®. Tree density was calculated as the sum of the total number of individual polygons (trees) within the tree cover output file after isolation using a negative buffer post-processing technique. Feature-extracted data were compared to ground reference measurements from Utah’s Division of Wildlife Resources Range Trend Project (DWR-RTP). We found that the proposed feature-extraction techniques used for measuring cover and density were highly correlated to ground reference and DWR-RTP datasets. Feature-extracted measurements of cover generally showed a near 1:1 relationship to these data, while tree density was underestimated; however, after calibration for juvenile trees, a near 1:1 relationship was realized. Feature-extraction techniques used in this study provide an efficient method for assessing important rangeland indicators, including: density, cover, and extent of P-J tree encroachment. Correlations found between field and feature-extracted data provide evidence to support extrapolation between the two approaches when assessing woodland encroachment. 相似文献