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641.
通过将玉米淀粉与氢氧化钠、三氯化铝和无水碳酸钠在恒温磁力搅拌器上搅拌、加热,使得玉米淀粉改性,制得改性淀粉絮凝剂,并研究了改性淀粉絮凝剂对含油废水的处理效果.试验结果显示,在搅拌速度与时间分别为快搅速度200 r/min,快搅时间0.5 min;慢搅速度100 r/min,慢搅时间3 min的情况下,使用改性淀粉絮凝剂处理含油废水时,COD去除率为77.94%、石油类去除率为61.2%、透光率为62.7%、SS去除率为79.96%;最佳反应条件为:投药量为12 mg/L、温度为5~30℃、pH值为6-8.  相似文献   
642.
基于复杂自适应系统理论构建了社会经济环境系统模型,采用计算实验方法模拟分析了太湖流域在经济优先和水环境保护优先2种管理模式下的动态演化过程,得到了农业与工业经济发展水平、就业状况和水环境改善情况的演化规律.结果表明,在综合考虑社会、经济、水环境的基础上,2种管理模式均能在一定程度上实现经济和就业的增长,同时改善水环境.环境保护优先模式虽能有效保护水环境,却会牺牲部分经济发展和就业保证.不同地区在演化过程中表现出差异性,常州和湖州经济获得较快增长;苏州、上海在就业方面做出较大贡献;无锡和苏州水环境改善效果最为明显.  相似文献   
643.
We investigate the role of domestic allowance allocation and global emissions constraints for the carbon-market impacts of linking the EU Emissions Trading Scheme (ETS) internationally. Employing a quantitative simulation model of the global carbon market, we find that the economic benefits from connecting the European ETS to emerging non-EU schemes strongly depend on the regional allowance allocation of the linking participants: In a world of moderate carbon constraints, an economically efficient regional allowance allocation induces a much stronger fall in total compliance costs than a sub-optimal (i.e. too high) domestic allocation of emissions permits. However, a more efficient (i.e. stricter) allocation shifts abatement efforts and compliance costs to energy-intensive industries which are covered by the domestic ETS. We further find that committing to ambitious global emissions reduction targets (compatible with stabilizing CO2 concentrations at 450 ppm) induces much stronger regional abatement efforts and substantially higher compliance costs for the abating regions. In such an ambitious climate policy regime, an efficient domestic allocation of allowances is even more important from an economic perspective: Here, linking emissions trading schemes diminishes the associated compliance costs on the largest scale.
J. OnigkeitEmail:
  相似文献   
644.
An important aspect in the linking of different emissions trading schemes is the degree to which these systems allow (or ban) external offset project categories. The EU Emission Trading Scheme (EU ETS) currently allows the use of credits from energy and industry projects developed under the Kyoto Protocol’s Joint Implementation (JI) and Clean Development Mechanism (CDM) but excludes the use of carbon credits from forestry projects for compliance in the EU ETS. Forestry credits generated by the CDM have a limited lifetime and expire at the end of a project’s crediting period, or earlier if the carbon stock for which the credits have been issued ceases to exist. According to the recently adopted amendment of the EU ETS Directive forestry credits will remain to be excluded until 2020. The present article reviews how the New South Wales Greenhouse Gas Abatement Scheme (Australia), the Regional Greenhouse Gas Initiative (US) and the voluntary scheme of the Chicago Climate Exchange integrate forestry offsets into the respective system and how they deal with the risk of losing stored and credited biomass. By comparing the results of different scenarios this article shows how differences in the treatment of forestry offsets could impact the efforts to link various emission trading systems in future.
A. TuerkEmail:
  相似文献   
645.
We address the future of science and governance for the California Delta, focusing on the CALFED Bay-Delta Program, an interagency, multi-stakeholder effort to understand and manage the Delta for multiple purposes. We portray a Delta history as a coevolutionary process between science, governance and ecosystems. Global integrated environmental assessments (IEA) provide insights into understanding complex, dynamic socio-ecological systems. Many of the discursive stakeholder and scientific activities that have arisen under CALFED are similar to IEA and remain essential to the shared learning needed to effectively interact with a dynamic Delta. More deliberately enmeshing environmental monitoring, analysis, and collective learning into Delta governance will improve outcomes.  相似文献   
646.
pUCD-recA重组发光菌构建及对遗传毒性污染物响应作用   总被引:1,自引:1,他引:0  
基因重组发光菌在水质毒性的评价中具有重要的作用,本研究从分析污染物毒性损伤的机制出发,构建新型pUCD-recA基因重组发光菌.用PCR法从大肠杆菌W3110中扩增recA基因,将其与pGEM-T easy载体连接后测序.测序正确的recA片段及pUCD615载体均用BamHⅠ、EcoRⅠ双酶切,连接后电转化导入宿主菌JM109.挑取克隆,提取质粒用PCR鉴定,阳性克隆再进行测序.将构建成功的pUCD-recA载体转化入大肠杆菌RFM443,加入相应的遗传毒性污染物,观察发光响应作用.结果表明,recA基因PCR扩增出的片段为293 bp,测序结果与GenBank中的recA序列进行BLAST比对,同源性为99%,表明扩增序列正确.与pUCD615载体连接后的测序结果表明,recA基因已正确地插入到pUCD615的多克隆位点,方向和读码框正确,重组发光菌载体构建成功.将构建好的重组载体转化入RFM443宿主菌,加入遗传毒性污染物观察响应效果.丝裂霉素C(MMC)对pUCD-recA重组发光菌诱导效果最好,0.01 mg/L即可有很好的响应曲线;N′-甲基-N′-硝基亚硝基胍(MNNG)则在50~100 mg/...  相似文献   
647.
Introduction: Driving under the influence (DUI) increases the probability of motor-vehicle collisions, especially for motorcycles with less protections. This study aimed to identify commonalities and differences between criminally DUI offenses (i.e., with a blood alcohol concentration (BAC) of 80 mg/dL or higher) committed by motorcyclists and car drivers. Methods: A total of 10,457 motorcycle DUIs and 8,402 car DUIs were compared using a series of logistic regression models, using data extracted from the documents of adjudication decisions by the courts of Jiangsu, China. Results: The results revealed that offenders from the high-BAC group (i.e., 200 mg/dL or higher) accounted for more than 20% of the total DUI offenses, and were more likely to be involved in a crash and punished with a longer detention. Motorcyclists had a higher likelihood of crash involvement, and were also more likely to be responsible for single-vehicle crashes associated with higher odds of injury sustained, compared to alcohol-impaired car drivers. In the verdict, motorcycle offenders were more likely to receive a less severe penalty. Conclusions: Interventions are clearly required to focus on reducing in the high-BAC group of offenders. For alcohol-impaired motorcyclists, their risks of crash and injury against BAC climb more steeply than the risks for car drivers. The factors including frequent occurrences, uncertainty of detection, and short-term sentences may weaken the deterrence effect of the criminalization of motorcycle DUI. Practical Applications: The traffic-related adjudication data support traffic safety analysis. Strategies such as combating motorcycle violations (e.g., unlicensed operators or driving unsafe vehicles), undertaking education and awareness campaigns, are expected for DUI prevention.  相似文献   
648.
The global increase in the use of, and reliance on, plastics has prompted the demand for acrylonitrile-butadiene-styrene (ABS) resin in various fields. With this increased requirement, numerous failures have occurred in the ABS process. Those incidents, resulting from electrostatic discharge, powder accumulation, heat accumulation, construction sparks, and plant fires, have caused dust fire and explosions.In this study, the ABS resin was gleaned from the site and tested for its explosion parameters, including minimum ignition temperature of dust cloud (MITC), minimum ignition energy (MIE), and minimum explosion concentration (MEC). To improve loss prevention in the manufacturing process, ferric oxide (Fe2O3) as an inert additive was added in the ABS powder. According to the MIE test, Fe2O3 has an apparent inhibiting effect on dust explosion for the ABS dust. With the proportion of Fe2O3 increased from 25 to 50 mass% in ABS, the MIE increased from 67 to 540 mJ. The explosion tests via 20-L apparatus indicated that Fe2O3 mixed with ABS could not increase the MEC significantly. However, the explosion pressure dropped by increasing in the ratio of Fe2O3 in ABS. This inerting strategy of ABS was deemed to substantially lessen the probability and severity of fire and explosion.  相似文献   
649.
通过室外试验的方法、从二维角度入手并将排桩参数与瑞利波波长建立联系研究了几何参数变化时隔振半径的变化。结果表明:单排桩可取得整体性的隔振特点,并且隔振效果最佳的区域在桩后较近的距离;桩长增加可使其隔振效果提升且隔振半径随桩长与波长比值的增加而增加,当桩长与波长比值小于0.320时,隔振半径为0;随比值增加到0.820左右,隔振半径增加到约0.680 m。桩间距的增加可使其隔振效果变差,隔振半径随桩间距与波长比值增加而降低,当比值达到0.300~0.430时,隔振半径长度降为0。振源距离增加可使得排桩隔振效果增强,而隔振半径随振源距与波长比值增加而增加,当比值在0.165~0.305的范围内时,隔振半径为0;随比值增加到0.808左右,隔振半径的长度增加到约0.512 m。  相似文献   
650.
Voluntary environmental governance is a widely used policy approach that has been criticized for its lack of effectiveness. This raises fundamental questions about how to design processes that can advance voluntary programmes in a way that makes them more successful. In this paper, we analyse a government-initiated dialogue process to phase out hazardous chemicals through voluntary action by the Swedish textile industry. The analysis shows that information transfer primarily motivated business participation, while consumer pressure, regulatory threats and traditions of government–business cooperation played minor roles. The institutional design of the dialogue ensured close interaction within a homogeneous group, but collective actions were limited by disagreement about the problems to be addressed, prior unilateral environmental commitments by leading companies, and ambivalent engagement. This case provides valuable insights into the effect of institutional design on the actual interplay between business and government and its effects on voluntary governance.  相似文献   
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