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221.
Contributions of biofilm and suspended sludge to nitrogen transformation and
nitrous oxide emission in hybrid sequencing batch system 总被引:2,自引:0,他引:2
Ingwei Wayne Lo Kwang Victor Lo Don S Mavini Dean Shiskowski William Ramey 《环境科学学报(英文版)》2010,22(7):953-960
Hybrid system combines the nature of suspended growth and attached growth has been widely applied to wastewater treatment.
In this research, the contributions to N transformation and N2O emission by biofilm and suspended sludge in the hybrid sequencingbatch
reactor for a simultaneous nitrification, denitrification and phosphorus removal process were investigated. For the hybrid system,
nitrification occurred mostly in the suspended sludge, while the biofilm played the major role in denitrification. The interaction of
the biofilm and the suspended sludge in the same reactor resulted in a better overall nitrogen removal performance with simultaneous
nitrification and denitrification. However, N2O emission was the main end product of nitrogen removal for the hybrid system; while
it was N2 for the biofilm. The relative low N2O emissions from the pure biofilm and the pure suspended sludge corresponded to the
relatively high nitrate at the end of the aeration period compared with the hybrid system. 相似文献
222.
Dean O. Cliver 《Food and environmental virology》2009,1(1):3-9
Viruses are often transmitted via food and the environment. Contamination may be controlled either by preventing its occurrence
or by inactivating the contaminating virus. The majority of agents transmitted in this way are human enteric viruses, produced
either in the intestines or the liver. They are shed in human feces (noroviruses also in vomitus) in a broad range of circumstances,
and they are relatively stable outside the host. Non-enteric viruses are less often transmitted via foods and are generally
less environmentally stable. Insofar as vaccines are available, they are able to prevent fecal shedding. Viruses shed in feces
via the water-carriage toilet may be eliminated by proper treatment and disinfection of the wastewater. In the foods context,
the most effective antiviral measures are cooking and hand washing. Detection methods are most useful after the fact, in investigating
outbreaks and devising preventive measures. 相似文献
223.
Problem
As the evidence-based movement has advanced in public health, changes in public health practices have lagged far behind creating a science to service gap. For example, science has produced effective falls prevention interventions for older adults. It now is clearer WHAT needs to be done to reduce injury and death related to falls. However, issues have arisen regarding HOW to assure the full and effective uses of evidence-based programs in practice.Summary
Lessons learned from the science and practice of implementation provide guidance for how to change practices by developing new competencies, how to change organizations to support evidence-based practices, and how to change public health systems to align system functions with desired practices. The combination of practice, organization, and system change likely will produce the public health benefits that are the promise of evidence-based falls prevention interventions.Impact on public health
For the past several decades, the emphasis has been solely on evidence-based interventions. Public health will benefit from giving equal emphasis to evidence-based implementation.Impact on Industry
We now have over two decades of research on the effectiveness of fall prevention interventions. The quality of this research is judged by a number of credible international organizations, including the Cochrane Collaboration (http://www.cochrane.org/), the American and British Geriatrics Societies, and the Campbell Collaboration (http://www.campbellcollaboration.org/). These international bodies were formed to ponder and answer questions related to the quality and relevance of research. These developments are a good first step. However, while knowing WHAT to do (an evidence-based intervention) is critical, we also need to know HOW to effectively implement the evidence. Implementation, organization change, and system change methods produce the conditions that allow and support the full and effective use of evidence-based interventions. It is time to focus on utilization of implementation knowledge in public health. Without this focus the vast amount on new evidence being generated on the prevention of falls and related injuries among older adults will have little impact on their health and safety. 相似文献224.
Daniel L. Keller Brian G. Laub Paul Birdsey David J. Dean 《Environmental management》2014,54(3):465-478
Tamarisk removal is a widespread restoration practice on rivers in the southwestern USA, but impacts of removal on fish habitat have rarely been investigated. We examined whether tamarisk removal, in combination with a large spring flood, had the potential to improve fish habitat on the San Rafael River in southeastern Utah. We quantified habitat complexity and the distribution of wood accumulation in a tamarisk removal site (treated) and a non-removal site (untreated) in 2010, 1 year prior to a large magnitude and long-duration spring flood. We used aerial imagery to analyze river changes in the treated and untreated sites. Areas of channel movement were significantly larger in the treated site compared to the untreated site, primarily because of geomorphic characteristics of the channel, including higher sinuosity and the presence of an ephemeral tributary. However, results suggest that tamarisk removal on the outside of meander bends, where it grows directly on the channel margins, can promote increased channel movement. Prior to the flood, wood accumulations were concentrated in sections of channel where tamarisk had been removed. Pools, riffles, and backwaters occurred more frequently within 30 m upstream and downstream of wood accumulations compared to areas within 30 m of random points. Pools associated with wood accumulations were also significantly larger and deeper than those associated with random points. These results suggest that the combination of tamarisk removal and wood input can increase the potential for channel movement during spring floods thereby diversifying river habitat and improving conditions for native fish. 相似文献
225.
Xu Xiang Gu Dean Xu Bing Yang Chenli Wang Ling 《Environmental science and pollution research international》2022,29(24):35934-35943
Environmental Science and Pollution Research - Alzheimer’s disease (AD) is the most frequent neurodegenerative disease and it is difficult to have an effective and simple method for AD early... 相似文献