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491.
Maritime shipping has two vectors of spreading marine invasive species: ballast water inside the ship and biofouling on the hulls outside the ship. While some attention has focused on ballast water, virtually none is focused on biofouling. This paper offers a quantitative analysis of economic incentives for shippers and regulating ports to address both pollution vectors. The strategies to address the vectors are induced by incentive mechanisms involving liability, subsidies and taxes. Results show these offer ample incentives in order to truly foster abatement of both vectors. Data from North America's Pacific coast is included in the analysis.  相似文献   
492.
Wastewater management in small and medium-sized enterprises representing the chemical and food industries was investigated. The results showed that wastewater discharged from an ink-production factory was highly contaminated with organic pollutants. Anaerobic biological treatment followed by chemical coagulation using ferric chloride aided with lime proved to be very effective and produced an effluent that complied with national regulatory standard for wastewater discharge into public sewage network. Also, management of wastewater from a confectionery factory representing the food sector was carried out. Aerobic biological treatment using plastic-packed trickling filter proved to be an effective treatment method. However, application of in-plant control measures alleviated the requirement for the construction of a wastewater treatment plant. The applied pollution prevention and cleaner production measures involved good housekeeping, recovery of spent chocolate, modification of floor cleaning and installation of suction devices for the removal of sugar and starch powders. All improvement measures were documented by cost/benefit analysis.  相似文献   
493.
畜禽粪便中大量有机污染物污染着人们赖以生存的土壤和水体,粪尿分解产生的大量有害气体污染了大气。本文结合日照市畜牧业生产的实际,对日照市畜牧业生产对环境的污染现状进行了分析,找出了日照市畜牧业生产对环境污染产生的主要原因和存在问题,提出畜牧业生产对环境污染的防治对策。  相似文献   
494.
城区天然气配气站噪声超标已成为供气部门亟待解决的难题,文章分析了配气站噪声污染现状,指出噪声产生原因主要为天然气流动,供气量增长使设备超负荷运行等7个方面。分别针对现有配气站和新建、改扩建站场提出降噪措施,指出设备在额定范围内运行、气体流速控制、工艺改造等是噪声控制的重要手段。并对城区天然气配气站噪声治理的进一步研究提出了建议。  相似文献   
495.
从胜利油田回注水中筛选得到一株硫酸盐还原菌,命名为zsz1209。经过16SrDNA序列分析,鉴定zsz1209为梭菌属(Clostridium)。实验研究了zsz109的生理特性,并对通过调节环境pH来抑制菌株zsz1209生长繁殖的可行性进行了探讨。实验结果表明:菌株zsz1209的理想碳源为乙酸钠,在30~60℃之间可较好地生长;SOi浓度低至50mg/L时,生长未受到明显抑制。当培养环境pH高至8.5~9.0或低至3.5~4.0时,检测菌株zsz1209对SO4^2-和碳源(COD)的利用情况,发现zsz1209的生长受到明显抑制,结果表明利用改变环境pH来抑制微生物对油田的腐蚀具有可行性。  相似文献   
496.
利用2000—2007年大气污染物排放量数据和同期环境空气质量监测数据,分析了江苏省主要大气污染物减排与环境空气质量变化的相关性。结果表明,近年来江苏省SO2排放量与环境空气中SO2浓度存在正相关,而烟尘和粉尘排放总量与空气中可吸入颗粒物的浓度呈现出弱的负相关关系。对江苏省经济发展和环境关系的进一步分析揭示,江苏省环境库兹涅茨曲线呈现出倒U型关系,表明江苏省已经进入经济环境双赢区间,但近年来政策对经济环境关系的影响突出。该研究对中国十二五环境管理政策的制定有着重要的参考意义。  相似文献   
497.
农村环境问题已成为中国实现农业可持续发展、提高农民生活质量、建设和谐社会的重要制约因素,特别是在经济发达地区,农村环境问题尤为突出。文中以江苏省丹阳市为例,对发达地区农村环境问题进行深入分析,并从保障饮用水安全、加强农村生活污水和生活垃圾处理处置、减少农业面源污染、合理布局和控制工业污染源等方面提出对策建议。  相似文献   
498.
化学实验中,经常会出现空白值异常的情况。文中从可能对空白值产生影响的各个因素逐一进行分析,并在此基础上提出了控制空白值的手段和措施。  相似文献   
499.
Background: Two of the 3 standardized field sobriety tests that U.S. law enforcement uses at roadside checks have a postural equilibrium component to them. Those tests have been validated to detect impairment caused by blood alcohol concentrations (BACs) of 0.08 g/dL or above. Many medical and traffic safety associations support a lower limit, and one state, Utah, has passed a law to lower the limit to 0.05 g/dL. Many studies have examined the effects of alcohol on postural control (of which postural equilibrium is a component), with a consensus emerging that impairment is usually found at BACs greater than 0.06 g/dL. Most of these studies, however, had a relatively small number of subjects, usually between 10 and 30. The current study collected data from a much larger sample.

Objective: The objective of this study was to provide additional evidence that posture control is negatively affected at BACs greater than 0.06 g/dL or breath alcohol concentrations (BrACs) of 0.06 g/210 L.

Method: This was a between-subjects study, with BrAC group as the independent variable (5 levels: 0.00, 0.04, 0.06, 0.08, and 0.10 g/210 L); 4 measures of postural control as the dependent variables; and age, height, and weight as the covariates. Posture control was measured with a force-sensing platform connected to a computer. The feet's center of pressure (CoP) on the platform was recorded and the corresponding movement of the body in the anterior–posterior and lateral planes was derived. Participants (N = 96) were randomly assigned to one of the BrAC groups. Positive BrAC groups were compared to the zero BrAC group. Data were examined with hierarchical multiple regression.

Results: Adjusted for age, height, and weight, the main effect of lateral CoP with eyes open was not statistically significant. There was a statistically significant main effect of alcohol on anterior–posterior CoP excursion with eyes open and with eyes closed and lateral CoP excursion with eyes closed. For all 3 of those variables, only BrACs of 0.08 and 0.10 g/210 L produced differences against zero BrAC. Although the main effect of alcohol on Lateral CoP Excursion with eyes open was not statistically significant, the contrasts between 0 and 0.08 and 0 and 0.10 g/210L BrAC were in the hypothesized direction.

Conclusion: The current study did not directly address the issue of whether the sobriety tests are sensitive to BrACs of 0.05 g/210 L or above; rather, it provides additional evidence that postural control, one of the components of those tests, is relatively unaffected by BrACs lower than 0.08 g/210 L. Additional research is needed on the diagnostic characteristics of the sobriety tests at BrACs lower than 0.08 g/210 L.  相似文献   

500.
某钢企大型低位料仓为汽车卸料,料仓厂房内空高,跨度大,料仓上部贯通,物料落差大,卸料中产生大量粉尘,环境污染问题典型突出。通过对低位料仓汽车卸料产尘特性分析,采取加强生产管理、组织汽车有序卸料、料仓厂房有效密闭、合理设计捕尘方式和布袋除尘系统等措施,能够有效地控制粉尘污染。除尘系统具有投资及运行费用少,除尘效果明显的优点。  相似文献   
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