全文获取类型
收费全文 | 639篇 |
免费 | 14篇 |
国内免费 | 12篇 |
专业分类
安全科学 | 63篇 |
废物处理 | 18篇 |
环保管理 | 153篇 |
综合类 | 131篇 |
基础理论 | 147篇 |
污染及防治 | 96篇 |
评价与监测 | 33篇 |
社会与环境 | 19篇 |
灾害及防治 | 5篇 |
出版年
2023年 | 7篇 |
2022年 | 5篇 |
2021年 | 13篇 |
2020年 | 16篇 |
2019年 | 6篇 |
2018年 | 19篇 |
2017年 | 16篇 |
2016年 | 27篇 |
2015年 | 17篇 |
2014年 | 23篇 |
2013年 | 48篇 |
2012年 | 20篇 |
2011年 | 40篇 |
2010年 | 20篇 |
2009年 | 28篇 |
2008年 | 32篇 |
2007年 | 29篇 |
2006年 | 33篇 |
2005年 | 29篇 |
2004年 | 19篇 |
2003年 | 23篇 |
2002年 | 25篇 |
2001年 | 14篇 |
2000年 | 20篇 |
1999年 | 6篇 |
1998年 | 7篇 |
1997年 | 5篇 |
1996年 | 9篇 |
1995年 | 12篇 |
1994年 | 9篇 |
1993年 | 6篇 |
1992年 | 9篇 |
1991年 | 8篇 |
1990年 | 5篇 |
1988年 | 8篇 |
1987年 | 5篇 |
1986年 | 3篇 |
1985年 | 4篇 |
1984年 | 2篇 |
1983年 | 5篇 |
1982年 | 6篇 |
1981年 | 10篇 |
1980年 | 6篇 |
1979年 | 2篇 |
1977年 | 2篇 |
1976年 | 1篇 |
1974年 | 1篇 |
1973年 | 1篇 |
1962年 | 1篇 |
1956年 | 1篇 |
排序方式: 共有665条查询结果,搜索用时 15 毫秒
501.
Stephanie J. Tuttle Author Vitae Author Vitae Mary Lynn Buonarosa Author Vitae 《Journal of Safety Research》2009,40(3):191-415
Introduction
This study compared the conspicuity of three types of first-responder safety garments (NFPA 1971-2007 turnout gear coats, and ANSI/ISEA 107 and 207 safety vests).Method
Participants drove instrumented vehicles on a closed track during both daytime and nighttime, indicating when they could first detect pedestrians in a simulated emergency response scene. Pedestrians wore one of the safety garments and stood on either side of the emergency scene, facing or perpendicular to oncoming traffic, and either stationary or walking in place.Results
All three garment standards provided equal levels of conspicuity, in that the distances at which the pedestrians were detected were equivalent. Time of day was a significant factor, with longer mean detection distances being observed in daytime. Pedestrian orientation was significant, with mean detection distances being longest when facing traffic. Pedestrian motion did not result in significant differences in detection distance.Discussion
The results suggest that all three garment types studied are equivalent in making first responders conspicuous as pedestrians when working an emergency response scene in close proximity to traffic.Impact on Industry
Whether an NFPA or ANSI/ISEA compliant is worn, first responders are equally likely to be detected by passing motorists, and as such these garments should be considered to be equivalent. 相似文献502.
Mary K. Hendrickson Harvey S. JamesJr. William D. Heffernan 《Journal of Agricultural and Environmental Ethics》2008,21(4):311-328
We consider the implications of trends in the number of U.S. farmers and food imports on the question of what role U.S. farmers
have in an increasingly global agrifood system. Our discussion stems from the argument some scholars have made that American
consumers can import their food more cheaply from other countries than it can produce it. We consider the distinction between
U.S. farmers and agriculture and the effect of the U.S. food footprint on developing nations to argue there might be an important
role for U.S. farmers, even if it appears Americans don’t need them. For instance, we may need to protect U.S. farmland and,
by implication, U.S. farmers, for future food security needs both domestic and international. We also explore the role of
U.S. farmers by considering the question of whether food is a privilege or a right. Although Americans seem to accept that
food is a privilege, many scholars and commentators argue that, at least on a global scale, food is a right, particularly
for the world’s poor and hungry. If this is the case, then U.S. farmers might have a role in meeting the associated obligation
to ensure that the poor of the world have enough food to eat. We look at the consequences of determining that food is a right
versus a privilege and the implications of that decision for agricultural subsidies as well as U.S. agriculture and nutrition
policies. 相似文献
503.
Cowan-Ellsberry CE Dyer SD Erhardt S Bernhard MJ Roe AL Dowty ME Weisbrod AV 《Chemosphere》2008,70(10):1804-1817
National and international chemical management programs are assessing thousands of chemicals for their persistence, bioaccumulative and environmental toxic properties; however, data for evaluating the bioaccumulation potential for fish are limited. Computer based models that account for the uptake and elimination processes that contribute to bioaccumulation may help to meet the need for reliable estimates. One critical elimination process of chemicals is metabolic transformation. It has been suggested that in vitro metabolic transformation tests using fish liver hepatocytes or S9 fractions can provide rapid and cost-effective measurements of fish metabolic potential, which could be used to refine bioconcentration factor (BCF) computer model estimates. Therefore, recent activity has focused on developing in vitro methods to measure metabolic transformation in cellular and subcellular fish liver fractions. A method to extrapolate in vitro test data to the whole body metabolic transformation rates is presented that could be used to refine BCF computer model estimates. This extrapolation approach is based on concepts used to determine the fate and distribution of drugs within the human body which have successfully supported the development of new pharmaceuticals for years. In addition, this approach has already been applied in physiologically-based toxicokinetic models for fish. The validity of the in vitro to in vivo extrapolation is illustrated using the rate of loss of parent chemical measured in two independent in vitro test systems: (1) subcellular enzymatic test using the trout liver S9 fraction, and (2) primary hepatocytes isolated from the common carp. The test chemicals evaluated have high quality in vivo BCF values and a range of logK(ow) from 3.5 to 6.7. The results show very good agreement between the measured BCF and estimated BCF values when the extrapolated whole body metabolism rates are included, thus suggesting that in vitro biotransformation data could effectively be used to reduce in vivo BCF testing and refine BCF model estimates. However, additional fish physiological data for parameterization and validation for a wider range of chemicals are needed. 相似文献
504.
Hydroponic phytoremediation of Cd, Cr, Ni, As, and Fe: can Helianthus annuus hyperaccumulate multiple heavy metals? 总被引:1,自引:0,他引:1
Sundance sunflowers were subjected to contaminated solutions containing 3, 4, or 5 heavy metals, with and without EDTA. The sunflowers exhibited a metal uptake preference of Cd=Cr>Ni, Cr>Cd>Ni>As and Fe>As>Cd>Ni>Cr without EDTA and Cr>Cd>Ni, Fe>As>Cd>Cr>Ni with EDTA. As uptake was not affected by other metals, but it decreased Cd and Ni concentration in the stems. The presence of Fe improved the translocation of the other metals regardless of whether EDTA was present. In general, EDTA served as a hindrance to metal uptake. For the experiment with all five heavy metals, EDTA decreased Cd in the roots and stems from 2.11 to 1.36 and from 2.83 to 2.3 2mg g(-1) biomass, respectively. For the same conditions, Ni in the stems decreased from 1.98 to 0.94 mg g(-1) total metal uptake decreased from 14.95 mg to 13.89 mg, and total biomass decreased from 2.38 g to 1.99 g. These results showed an overall negative effect in addition of EDTA. However it is unknown whether the negative effect was due to toxicity posed by EDTA or the breaking of phytochelatin-metal bonds. The most important finding was the ability of Sundance sunflowers to achieve hyperaccumulator status for both As and Cd under all conditions studied. Ni hyperaccumulator status was only achieved in the presence of three metals without EDTA. 相似文献
505.
Lee MH Clingenpeel SC Leiser OP Wymore RA Sorenson KS Watwood ME 《Environmental pollution (Barking, Essex : 1987)》2008,153(1):238-246
A variety of naturally occurring bacteria produce enzymes that cometabolically degrade trichloroethene (TCE), including organisms with aerobic oxygenases. Groundwater contaminated with TCE was collected from the aerobic region of the Test Area North site of the Idaho National Laboratory. Samples were evaluated with enzyme activity probes, and resulted in measurable detection of toluene oxygenase activity (6-79% of the total microbial cells). Wells from both inside and outside contaminated plume showed activity. Toluene oxygenase-specific PCR primers determined that toluene-degrading genes were present in all groundwater samples evaluated. In addition, bacterial isolates were obtained and possessed toluene oxygenase enzymes, demonstrated activity, and were dominated by the phylotype Pseudomonas. This study demonstrated, through the use of enzymatic probes and oxygenase gene identification, that indigenous microorganisms at a contaminated site were cometabolically active. Documentation such as this can be used to substantiate observations of natural attenuation of TCE-contaminated groundwater plumes. 相似文献
506.
Lourencetti C Favoreto R Marchi MR Ribeiro ML 《Journal of environmental science and health. Part. B》2007,42(6):697-705
Persistent organic pollutants (POPs), organochlorine pesticides and polychlorinated biphenyls (PCBs), listed as per the Stockholm Convention (alpha -HCH, beta -HCH, gamma -HCH, p,p'-DDT, o,p'-DDT, p,p'-DDD, p,p'-DDE, aldrin, endrin, dieldrin, PCBs 28, 52, 118, 138, 153, and 180), were analyzed in municipal solid waste (MSW) compost samples from three different Brazilian composting plants located in three S?o Paulo State cities: Araras, Araraquara and S?o Paulo (Vila Leopoldinha). Quantitative and qualitative analyses were carried out using gas chromatography electron capture detection (GC-ECD) and gas chromatography mass spectrometry (GC-MS) (Ion Trap, electron impact ionization), respectively. The samples were analyzed in triplicate and the target POPs were not detected by GC-ECD. Twelve pollutants were identified in two samples when qualitative analysis (GC-MS) was used (beta -HCH, gamma -HCH, p,p'-DDT, o,p'-DDT, p,p'-DDD, and p,p'-DDE, PCBs 28, 118, 138, 153 and 180). The composting process has advantages such as urban solid waste reduction and landfill life-span increase, however the MSW compost quality, which can be utilized for agricultural purposes, should be evaluated and be controlled. This kind of study is the first step in making available information to answer questions regarding MSW compost for sustainable agricultural use, such as the pollutants accumulation in soil and in groundwater, and plants uptake. 相似文献
507.
Technical assessment of three layered cement-bonded boards produced from wastepaper and sawdust 总被引:1,自引:0,他引:1
The technical properties of three layered cement-bonded boards (CBBs) made from wastepaper and sawdust were investigated. The CBBs were produced at three density levels of 1000, 1200 and 1300 kg/m3 and at four cement/particle ratios of 2.0:1, 2.5:1, 3.0:1 and 3.5:1 on a weight to weight basis. The technical properties evaluated were modulus of rupture (MOR), modulus of elasticity (MOE), water absorption (WA) and thickness swelling (TS). The MOR values ranged from 4.85 to 11.69 MPa and MOE values ranged from 2.80 to 5.57 GPa. The mean values of WA and TS after 24 h of water soaking of the CBBs ranged from 18.18% to 40.49% and 3.55% to 12.13%, respectively. MOR and MOE of the CBBs increased with increase in board density, but MOR decreased with the increase in cement/particle ratio. On the other hand, WA and TS decreased with increase in board density and cement/particle ratio. CBBs produced from wastepaper and sawdust at cement/particle ratios of 3.0:1 and 3.5:1 are suitable for building construction such as paneling, ceiling and partitioning. 相似文献
508.
Brian Deal Cheryl Farello Mary Lancaster Thomas Kompare Bruce Hannon 《Environmental Modeling and Assessment》2000,5(1):47-62
A spatially explicit computer model is developed to examine the dynamic spread of fox rabies across the state of Illinois
and to evaluate possible disease control strategies. The ultimate concern is that the disease will spread from foxes to humans
through the pet population.
Modeling the population dynamics of rabies in foxes requires comprehensive ecological and biological knowledge of the fox
and pathogenesis of the rabies virus. Variables considered including population densities, fox biology, home ranges, dispersal
rates, contact rates, and incubation periods, can greatly effect the spread of disease. Accurate reporting of these variables
is paramount for realistic construction of a spatial model. The spatial modeling technique utilized is a grid-based approach
that combines the relevant geographic condition of the Illinois landscape (typically described in a georeferenced database
system) with a nonlinear dynamic model of the phenomena of interest in each cell, interactively connected to the other appropriate
cells (usually adjacent ones).
The resulting spatial model graphically links data obtained from previous models, fox biology, rabies information and landscape
parameters using various hierarchical scales and makes it possible to follow the emergent patterns and facilitates experimental
stimulus/result data collection techniques. Results of the model indicate that the disease would likely spread among the native
healthy fox population from East to West and would occur in epidemiological waves radiating from the point of introduction;
becoming endemic across the State in about 15 years. Findings also include the realization that while current hunting pressures
can potentially wipe out the fox in the State, some level of hunting pressure can be effectively utilized to help control
the disease.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
509.
Ivan J. Fernandez Mary Beth Adams Michael D. SanClements Stephen A. Norton 《Environmental monitoring and assessment》2010,171(1-4):149-161
The Bear Brook Watershed in Maine (BBWM), USA, and the Fernow Experimental Forest in West Virginia, USA, represent unique, long-term, paired, whole watershed, experimental manipulations focusing on the effects of nitrogen (N) and sulfur (S) deposition on temperate forests. Both watersheds began whole-ecosystem additions of N and S as (NH4)2SO4 in the fall of 1989, and both are entering their third decade of chronic enrichment of the treated watersheds, while the reference watersheds offer unique opportunities to evaluate forest watershed responses to recovery. Differences between BBWM and Fernow in the history of atmospheric deposition, soil properties, and forest composition all contribute to different response trajectories in stream chemical exports over time. The four watersheds represent a spectrum of N enrichment and retention, ranging from ≈98% N retention in the reference watershed in Maine, to ≈20% N retention in the treated watershed in West Virginia. Despite these differences, there is evidence that mechanisms of response in base cation leaching and other processes are similar among all four watersheds. In both cases, the history to date of two decades of research and monitoring has provided new insights into ecosystem response not evident in more traditional short-term research. 相似文献
510.
Md. M. Rashid Mary G. Kattou’a Issam A. Al-Khatib Chikashi Sato 《Environmental monitoring and assessment》2017,189(7):353
An application of treated sewage sludge on agricultural land has been widely accepted, as this method is simple and economical for disposal of wastewater residues. When applied properly on an agricultural land, sludge can replenish organic matter and nutrients in soil. Although sewage sludge has been used in agriculture in many parts of the world, its acceptability varies with different cultures and beliefs among farmers. Farmers’ concerns on sludge use are primarily due to its anthropogenic origin, pollutants that it carries, a general perception of sewage being dirty, and its offensive odor. This paper aims to investigate farmers’ perceptions on land application of treated sewage sludge on their farm. This study targeted two farming communities, namely, Anza and Beit Dajan villages, located in Jenin and Nablus districts in the West Bank, Palestine. In this study, a sample of 106 farmers were randomly selected and surveyed through a mixture of structured and open-ended questions. Results indicated that, overall, farmers have positive perceptions on land application of sludge. A majority of the farmers are in favor of the concept of sludge use when a planned wastewater treatment plant is constructed and it becomes operational. Results also indicate that a majority of the farmers are in favor of using sludge for fertilizing fruit trees, rather than growing vegetables and other plants in a greenhouse, and that many of them have knowledge of sludge properties and advantages and disadvantages of sludge use in agriculture. Despite the positive perceptions by the majority of farmers, a small fraction of the farmers are in disfavor of the use of sludge for the following reasons: psychological and social concerns, potential health risks, and their religious beliefs. Results further suggest that the land application of treated sewage sludge can be accepted by more farmers if the consumers are willing to buy agricultural products fertilized by sludge, sludge meets the public health requirements, and sludge is available at low costs. To improve farmers’ perceptions on the land application of sludge, several measures are recommended. 相似文献