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101.
文章首先对我国海洋环境保护现状进行了分析,然后通过对秦皇岛市海洋环境保护统一协调管理机制的探讨,提出了解决目前涉海地区普遍存在的“多头管海”,又“无人管海”这一制的海洋环境保护工作发展问题的途径。  相似文献   
102.
Setback distances between septic tank systems and the shorelines of Lake Okareka, New Zealand were determined from model simulations for a worst-case scenario, using the highest hydraulic conductivity and gradient measured in the field, removal rates of the microbial indicators (Escherichia coli and F-RNA phages) determined from a column experiment, and maximum values of the design criteria for the disposal system, and assuming an absence of an unsaturated zone, a continuous discharge of the raw effluent from a failed or non-complying treatment system (both indicators at concentrations of 1x10(7) counts/100 ml) into the groundwater and no sorption of pathogens in the aquifer. Modelling results suggest that the minimal setback distances were 16 m to satisfy the New Zealand Recreational Water Quality Guidelines for E. coli <126 per 100 ml (Ministry for the Environment, 1999) and 48 m to meet the Drinking-Water Standards for New Zealand 2000 for enteric virus <1 per 100 l (Ministry of Health, 2000). These distances may be applicable for other lakeshores in pumice sand aquifers with groundwater velocities <7 m/day. Findings of laboratory column and batch experiments provided an insight into the microbial attenuation and transport processes in pumice sand aquifers. Bacterial removal was predominately through filtration (87-88%) and partially by die-off (12-13%), while viral removal was by both die-off (45%) and filtration (55%). In addition, microbial die-off in groundwater without aquifer material (i.e., free microbes) was much lower than die-off in groundwater with aquifer material (i.e., sorbed microbes) and contributed only 2-6% to the total removal. This implies that the setback distances estimated from die-off rates for the free microbes, determined in the laboratory without considering aquifer media and other removal processes, which are often reported in the literature, could be larger than necessary.  相似文献   
103.
中国降水量高度效应及全球升温对它的影响   总被引:1,自引:1,他引:0  
利用中国气象中心160站点的实际观察资料,对中国半个世纪的降水变化进行了系统分析,发现中国的夏季降水量与海拔高度存在着很好的反相关关系;同时,全球升温使得降水量的高度效应增强,主要表现为高海拔降水量海拔效应明显增强,这主要是由全球升温引起环流系统增强所引起的.  相似文献   
104.
二级UASB厌氧工艺在制药废水中的应用   总被引:2,自引:0,他引:2  
抗菌素制药污水复杂,其CODCr高达39000mgL,硫酸盐的浓度在6500mgL左右,常规工艺很难处理,山东某制药厂采用了二级厌氧工艺处理此类废水,取得了良好的处理效果和经济效益。  相似文献   
105.
碳源投加方式对SBR工艺脱氮速率的影响   总被引:1,自引:0,他引:1  
为了提高生物反应器的脱氮效率,研究采用SBR处理模拟生活污水,利用醋酸钠作为碳源,考察碳源投加方式对脱氮速率的影响。结果表明,当温度为10~15℃,进水COD为330~550 mg/L时,采用不同的碳源投加方式,COD去除率均高于95%。进水一次投加2.4 g碳源,COD平均反应速率为5.3 mg/(g·h),平均反硝化速率为0.28 mg/(g·h)。进水、反应器运行3 h时分别投加1.2 g碳源,COD平均反应速率为6.89 mg/(g·h),平均反硝化速率为0.37 mg/(g·h)。进水、反应6 h时分别投加1.2 g碳源,COD平均反应速率为6.50 mg/(g·h),平均反硝化速率为0.52 mg/(g·h)。进水投加1.2 g碳源、反应器运行3 h和6 h时分别投加0.6 g醋酸钠碳源,COD平均反应速率为6.2 mg/(g·h),平均反硝化速率为0.39 mg/(g·h)。分次投加碳源能够提高COD反应速率和TN去除率,同时保持较高的硝化反硝化速率。  相似文献   
106.
应用Kaya恒等式的计算方法对我国4个直辖市2005-2009年的碳效率进行了评价和比较分析,结果显示:4个直辖市碳效率的排序在2005-2009年间没有发生变化,4个城市的碳效率都处于上升态势。  相似文献   
107.
活性污泥中活性微生物量是表征污染物去除能力的重要指标。探索了荧光染色法直接检测活性细菌的原理和测定方法,结果表明,大肠杆菌、唾液链球菌和铜绿假单胞杆菌的活菌细胞浓度与荧光光强的线性相关度都超过0.95;在惰性颗粒物浓度为20 mg/L到60 mg/L的范围内,其对荧光光强的影响可通过线性关系修正;搅拌速度为1 000 r/min且搅拌10 min时前处理效果最好。  相似文献   
108.
All seven emissions trading pilots in China operate independently. One challenge facing most of them is the low inclusion thresholds for enterprises and the few total covered emissions, which negatively influences the effects of the emissions trading systems (ETSs). Some pilot sites, such as Guangdong, Hubei, Tianjin and Beijing, have indicated their willingness to link their schemes with others. ETS linking could expand scheme coverages and therefore help to reduce the overall costs of achieving the linked schemes’ emissions control targets. Linking could also help to address the issues of carbon leakage and reduce price fluctuations. The potential benefits and feasibility of linking different pilot systems are analyzed in this article. The seven pilot regions are at different stages of social and economic development, with significant differences in total emissions and emissions structures as well as carbon abatement potentials and costs. Through linking, more-developed regions such as Beijing, Shanghai and Shenzhen, which are typically considered to face higher mitigation costs, will have the opportunity to achieve their emissions control targets by purchasing carbon units from less-developed regions, which will earn financial revenues from selling the units. To realize this win-win result, a series of policy and technical barriers at both the central government and pilot government levels needs to be overcome. Establishing a unified national emissions trading market would appear to be the ideal solution to these challenges, but it will take considerable time and will not be the short-term solution. In the absence of a unified national scheme, it is recommended that the central government encourage pilot schemes to link, that it develops corresponding national policies to support the linking efforts and that the pilot schemes that are intended to be linked coordinate on certain design elements. Based on the coordinating need, the major elements of an ETS can be divided into four categories: elements that need mutual recognition (cap setting and allowance allocation methods); elements that should be completely identical (compliance mechanisms, price containment measures, banking and borrowing rules, and offset mechanisms); technical elements that are preferably identical and easy to coordinate (MRV standards, technical registry standards); and elements that require no coordination (coverages and scopes).  相似文献   
109.
The decay of wood and other cellulosic materials by fungi cause significant economic loss. The widely used chromated copper arsenate was prohibited for the environmental impact and safety of arsenic and chromium. It was found that natural product hinokitiol (HK) had fungicidal and insecticidal activities, and its toxicity was bearable for the environment. We described the practical synthesis of HK-K salt. According to the GB/T18261-2000 and LY/T1283-1998, wood preservative performance of HK-K salt was tested. The results showed that the best inhibitory concentration of HK-K salt was 50 mg/L, for which the prevention effectiveness on mold is better, the killed value is between 0 and 1, and the corrosion-resistant for wood-rotting fungi is grade A.  相似文献   
110.
Biochar as an emerging carbonaceous material has exhibited a great potential in environmental application for its perfect adsorption ability. However, there are abundant persistent free radicals (PFRs) in biochar, so the direct and indirect PFRs-mediated removal of organic and inorganic contaminants by biochar was widely reported. In order to comprehend deeply the formation of PFRs in biochar and their interactions with contaminants, this paper reviews the formation mechanisms of PFRs in biochar and the PFRs-mediated environmental applications of biochar in recent years. Finally, future challenges in this field are also proposed. This review provides a more comprehensive understanding on the emerging applications of biochar from the viewpoint of the catalytic role of PFRs.  相似文献   
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