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31.
The spectre of regulatory reform carried out in a range of Western countries has generated concern amongst parts of the environmental policy community. Quality and effectiveness are said to be at stake, but empirically there is a dearth of data on the relationship between provisions for quality control and the effects on quality and effectiveness. This research addresses this lacuna by analysing the effects of different quality control provisions in the Netherlands and Denmark for a globally institutionalized environmental appraisal tool—Environmental Assessment (EA). Extensive technical provisions for quality control in the Netherlands have led to it being described as the ‘Rolls Royce’ of EA systems, while in Denmark the polity is expected to take charge of quality control. The effects of quality control are investigated through surveys and in-depth interviews with actors centrally engaged with EA implementation. The results show that quality control provisions are poorly related to the perceived quality and effectiveness of EA. Only the appropriateness of the scope of EA reports is perceived to be strongly related to quality control provisions. The findings are relevant for environmental policy communities concerned with quality control systems and effectiveness of policy appraisal tools and policy-makers contemplating regulatory reforms.  相似文献   
32.
The electro-Fenton (EF) process treatment of 0.1-M (rhodamine B) RhB solution was studied with different graphite cathode materials, and graphite felt (GF) was selected as a promising material in further investigation. Then, the degradation performances of gas diffusion electrode (GDE) and graphite felt (GF) were compared, and GDE was confirmed to be more efficient in RhB removal. The operational parameters such as Fe2+ dosage and current density were optimized, and comparison among different modified methods—polytetrafluoroethylene-carbon black (PTFE-CB), polytetrafluoroethylene-carbon nanotube (PTFE-CNT), electrodeposition-CB, and electrodeposition-CNT—showed 98.49 % RhB removal by PTFE-CB-modified cathode in 0.05 M Na2SO4 at a current density of 50 A/m2 and an air flow rate of 1 L/min after 20 min. Meanwhile, after cathode modified by PTFE-CB, the mineralization efficiency and mineralization current efficiency performed absolutely better than the pristine one. Cyclic voltammograms, SEM images, contact angles, and BET surface area were carried out to demonstrate stronger current responses and higher hydrophilicity of GF after modified. The value of biochemical oxygen demand/chemical oxygen demand (BOD5/COD) increased from 0.049 to 0.331 after 90-min treatment, suggesting the solution was biodegradable, and the modified cathode was confirmed to be stable after ten circle runs. Finally, a proposed degradation pathway of RhB was put forward.  相似文献   
33.
重型柴油车实际道路排放与行驶工况的相关性研究   总被引:5,自引:1,他引:4  
采用SEMTECH-D车载排放测试仪测量了东风柴油卡车在城市实际道路工况以及等速和加速工况下的油耗及污染物排放状况.测试结果显示,测试卡车实际道路综合百公里油耗为17.8 L,NOx、CO和HC排放因子分别为3.96、8.86和2.15g·km-1.其中主干道路况相对较差,油耗与排放因子较高,是所有测试道路平均水平的1.3~1.8倍左右.研究结果表明,重型车油耗及污染物排放与各行驶工况下的速度、加速度均密切相关,车辆在高速加速行驶状态下易产生高排放.车辆在30~50 km·h-1速度区间内等速行驶时,油耗与排放因子最为经济且环境友好.车辆在加速行驶时,油耗与NOx、CO排放因子可达到城市实际道路平均水平的2.0、2.2、1.4倍,急加速时达到2.8、2.1、14倍.应用比功率概念可准确描述车辆在各运行工况下的排放水平,但在重型车上缺乏实验依据,有待进一步研究.  相似文献   
34.
The cold and arid mountains and plateaus of High Asia, inhabited by a relatively sparse human population, a high density of livestock, and wildlife such as the iconic snow leopard Panthera uncia, are usually considered low risk for disease outbreaks. However, based on current knowledge about drivers of disease emergence, we show that High Asia is rapidly developing conditions that favor increased emergence of infectious diseases and zoonoses. This is because of the existing prevalence of potentially serious pathogens in the system; intensifying environmental degradation; rapid changes in local ecological, socio-ecological, and socio-economic factors; and global risk intensifiers such as climate change and globalization. To better understand and manage the risks posed by diseases to humans, livestock, and wildlife, there is an urgent need for establishing a disease surveillance system and improving human and animal health care. Public health must be integrated with conservation programs, more ecologically sustainable development efforts and long-term disease surveillance.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01599-7.  相似文献   
35.
Objective: The objective of this article is to provide empirical evidence for safe speed limits that will meet the objectives of the Safe System by examining the relationship between speed limit and injury severity for different crash types, using police-reported crash data.

Method: Police-reported crashes from 2 Australian jurisdictions were used to calculate a fatal crash rate by speed limit and crash type. Example safe speed limits were defined using threshold risk levels.

Results: A positive exponential relationship between speed limit and fatality rate was found. For an example fatality rate threshold of 1 in 100 crashes it was found that safe speed limits are 40 km/h for pedestrian crashes; 50 km/h for head-on crashes; 60 km/h for hit fixed object crashes; 80 km/h for right angle, right turn, and left road/rollover crashes; and 110 km/h or more for rear-end crashes.

Conclusions: The positive exponential relationship between speed limit and fatal crash rate is consistent with prior research into speed and crash risk. The results indicate that speed zones of 100 km/h or more only meet the objectives of the Safe System, with regard to fatal crashes, where all crash types except rear-end crashes are exceedingly rare, such as on a high standard restricted access highway with a safe roadside design.  相似文献   

36.
Aerobic treatment of swine manure was coupled with anaerobic digestion and microalgal cultivation. A 14-day aerobic treatment reduced the total solid content of swine manure by >15%. Ammonia and carbon dioxide were stripped by the air supplied, and this off-gas was further used to aerate the culture of Chlorella vulgaris. The microalgal growth rates in Bristol medium and the wastewater with the off-gas increased from 0.08 to 0.22 g/L/d and from 0.15 to 0.24 g/L/d, respectively. Meanwhile, the aerobically treated swine manure showed a higher methane yield during anaerobic digestion. The experimental results were used to establish a demonstration unit consisting of a 100 L composter, a 200 L anaerobic digester, a 60 L tubular photobioreactor, and a 300 L micro-open raceway pond.  相似文献   
37.
We constructed a survey system of radon/methane/nitrate/salinity to find sites of submarine groundwater discharge (SGD) and groundwater nitrate input. We deployed the system in Waquoit Bay and Boston Harbor, MA where we derived SGD rates using a mass balance of radon with methane serving as a fine resolution qualitative indicator of groundwater. In Waquoit Bay we identified several locations of enhanced groundwater discharge, out of which two (Childs and Quashnet Rivers) were studied in more detail. The Childs River was characterized by high nitrate input via groundwater discharge, while the Quashnet River SGD was notable but not a significant source of nitrate. Our radon survey of Boston Harbor revealed several sites with significant SGD, out of these Inner Harbor and parts of Dorchester Bay and Quincy Bay had groundwater fluxes accompanied by significant water column nitrogen concentrations. The survey system has proven effective in revealing areas of SGD and non-point source pollution.  相似文献   
38.
Although natural environments can help promote health, they also contain a number of dangers. This study attempted to examine how variations in the physical structure of a simulated natural environment influenced perceptions of both overall and specific types of danger, fear and preference before exploring the relationships between these variables. Three simulated walks through a natural environment differing in levels of prospect-refuge were created for the study. Respondents were randomly assigned to one of the conditions and asked to imagine taking the walk for real. In support of the typology, the results found that the walks with higher levels of prospect-refuge (higher visibility, fewer hiding places and more accessibility) were perceived as less dangerous and fearful and more preferred than walks with lower levels of prospect-refuge. However despite levels of prospect-refuge appearing to impact on the perceived likelihood of encountering a physical danger or becoming lost, they were not found to impact on the perception of encountering a social danger.  相似文献   
39.
Proving the viability of in situ bioremediation technologies and gathering data for its full‐scale implementation typically involves collecting multiple rounds of data and often completing microcosm studies. Collecting these data is cumbersome, time‐consuming, costly, and typically difficult to scale. A new method of completing microcosm studies in situ using an amendable sampling device deployed and incubated in groundwater monitoring wells provides actionable data to expedite site cleanup. The device, referred to as a Bio‐Trap® sampler, is designed to collect actively colonizing microbes and dissolved organic compounds from groundwater for analysis using conventional analytical techniques and advanced diagnostic tools that can answer very specific design and viability questions relating to bioremediation. Key data that can be provided by in situ microcosm studies using Bio‐Trap® samplers include definitively demonstrating contaminant destruction by using compound‐specific isotope analysis and providing data on the mechanism of the degradation by identifying the responsible microbes. Three case studies are presented that demonstrate the combined flexibility of Bio‐Trap® samplers and advanced site diagnostics. The applications include demonstrating natural attenuation of dissolved chlorinated solvents, demonstrating natural attenuation of dissolved petroleum compounds, and using multiple Bio‐Trap® samplers to comparatively assess the viability of bioaugmentation at a chlorinated solvent release site. At each of these sites, the in situ microcosm studies quickly and cost‐effectively answered key design and viability questions, allowing for regulatory approval and successful full‐scale implementation. © 2010 Wiley Periodicals, Inc.  相似文献   
40.
Arora, Kapil, Steven K. Mickelson, Matthew J. Helmers, and James L. Baker, 2010. Review of Pesticide Retention Processes Occurring in Buffer Strips Receiving Agricultural Runoff. Journal of the American Water Resources Association (JAWRA) 46(3):618-647. DOI: 10.1111/j.1752-1688.2010.00438.x Abstract: Review of the published results shows that the retention of the two pesticide carrier phases (runoff volume and sediment mass) influences pesticide mass transport through buffer strips. Data averaged across different studies showed that the buffer strips retained 45% of runoff volume (ranging between 0 and 100%) and 76% of sediment mass (ranging between 2 and 100%). Sorption (soil sorption coefficient, Koc) is one key pesticide property affecting its transport with the two carrier phases through buffer strips. Data from different studies for pesticide mass retention for weakly (Koc < 100), moderately (100 < Koc < 1,000), and strongly sorbed pesticides (Koc > 1,000) averaged (with ranges) 61 (0-100), 63 (0-100), and 76 (53-100) %, respectively. Because there are more data for runoff volume and sediment mass retention, the average retentions of both carrier phases were used to calculate that the buffer strips would retain 45% of weakly to moderately sorbed and 70% of strongly sorbed pesticides on an average basis. As pesticide mass retention presented is only an average across several studies with different experimental setups, the application of these results to actual field conditions should be carefully examined.  相似文献   
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