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911.
以环状膜生物反应器BAR模拟实际输水管道,研究了预氯化对管壁生物膜净水效能的影响及其性能恢复过程.结果表明:冲击性加氯后生物膜中异养菌数量迅速降低,几乎检测不出氨氧化细菌,然而,短时的冲击利于生物膜更新,增加了细菌生长潜能,恢复运行240h及144h之后预氯化生物膜中异养菌和氨氧化细菌数量均高于对照组.氯冲击明显降低了生物膜对氨氮的去除效果,余氯为0.5,1.5,3.0mg/L的BAR对氨氮去除率由对照组的79.01%分别降到32.10%、14.46%和9.88%,并出现了显著的亚硝酸盐氮积累,恢复运行120h和216h,管道生物膜即可恢复对氨氮和亚硝酸盐氮的去除效果.余氯量达到1.5mg/L时造成出水总磷浓度升高,恢复运行264h之后4台BAR对总磷的去除率均达到20%以上.氯对生物膜的氧化作用使得出水高锰酸盐指数升高,运行192h之后生物膜净水效果恢复.  相似文献   
912.
微波解吸载乙醇活性炭的试验研究   总被引:8,自引:0,他引:8  
针对酒精工业中产生的淡酒液用活性炭吸附 -微波解吸方法回收其中可利用的酒精。设计了固定床吸附器提纯淡酒液的流程 ,制定了活性炭吸附微波解吸的试验方案。结果表明 ,微波加热温度均匀 ,活性炭不会被过分加热分解 ,解吸速度快 ,能实现对被蒸发物质的选择加热 ,对要回收的物质可以浓缩回收  相似文献   
913.
京津冀及周边地区区域贸易隐含二氧化硫排放   总被引:2,自引:0,他引:2  
索成  赵红艳  王鑫  张强 《环境科学学报》2019,39(11):3916-3923
京津冀及周边地区(包括北京、天津、河北、山东、山西和河南)是我国大气污染重点控制区域,厘清这一地区内部各省各行业之间贸易隐含污染物排放是加强区域产业协作、推进区域大气污染联防联控的重要前提.本研究以二氧化硫(SO_2)为对象,结合自下而上排放清单与中国多区域投入产出(MRIO)模型,估算了2012年京津冀及周边地区各省(直辖市)和各行业之间的贸易隐含污染排放,并基于产业链分析了区域贸易对重点行业SO_2的排放贡献,识别了主导排放的区域贸易产业链.研究结果表明,在京津冀及周边地区六省市之间,河北和山西是主要隐含排放输出区域,北京和天津是主要的隐含排放输入区域.京津冀及周边地区SO_2排放主要来源于能源动力行业、金属冶炼和制品制造业、非金属矿物制品和化学工业,而装备制造业、建筑业和服务业是拉动四类重点行业SO_2排放的主要产业.进一步分析六省市内部排放与区域产业链之间的关系发现,山西省是主要的能源消费SO_2排放输出区域;河北省是主要的金属冶炼和金属制品隐含排放输出区域;河北和河南是主要的非金属矿物制品隐含排放输出区域;山西是主要的石化与化工隐含排放输出区域.以上结果有助于理解京津冀及周边地区大气污染排放与产业结构的关系,为制定区域环境管理政策,优化区域产业结构提供支撑.  相似文献   
914.
探讨了草浆黑液与赤铁矿流化床燃烧反应机理和工艺参数.通过差热分析得到关联式x/x_0=1-exp(-0.012t),可用于预测草浆黑液在流化床中燃烧时碱回收的转化率.实验表明,草浆黑液碱回收转化率可高达95%以上. ’  相似文献   
915.
为了探究土壤中苯胺回收率测定偏低的难点,笔者针对《土壤和沉积物 苯胺类和联苯胺类的测定 液相色谱-三重四极杆质谱法(征求意见稿)》中前处理阶段的问题,在优化部分前处理条件的基础上,研究土壤吸附、内标加入的时机以及还原剂(五水合硫代硫酸钠)和氨水对苯胺回收率的影响。结果表明:土壤吸附是导致苯胺加标回收率偏低的重要因素,与空白加标相比,含有一定量有机质的砂质壤土基体加标回收率减少了42.05%~60.89%。内标在不同阶段加入会对苯胺回收率产生显著影响,主要是由前处理过程中的基体吸附和挥发损失导致。加入还原剂和氨水对空白加标的苯胺回收率无显著影响,但对于含有一定量有机质的砂质壤土,加入氨水后苯胺加标回收率增加了59.57%,具有显著影响。  相似文献   
916.
The tolerance of terrestrial ecosystems of the Kola Peninsula to atmospheric deposition of acid-forming sulfur compounds and the risk of their excess input into these ecosystems have been assessed on the basis of the critical load concept. The most sensitive ecosystems (critical sulfur load <400 equiv/ha per year) occupy 58% of the total area of the peninsula. These are mainly pine, spruce, and birch forests (including open and crooked birch forests) growing on podzols formed on sandy boulder-pebble glacial deposits. The zones of ecological risk cover the northwestern and central parts of the peninsula near the Pechenganikel and Severonikel combined works (20% of the total area).  相似文献   
917.
Abstract

In order to achieve sustainable utilization of natural resources, save energy and protect environment and ecosystem, it is important for a region or a nation to develop and implement a viable waste recycling model from both theoretical and practical point of view. Some packaging recycling models operated in developed countries are introduced in this article. Aluminium can recovery and recycling is emphasized. Cost effective, economic and environmental benefit of different models are compared and analyzed. The result shows that all recycling models have their characteristics due to the initial purpose of recovery and the situation of the implementing country. However, all the models contribute to the reduction of municipal solid waste disposal and resources conservation.  相似文献   
918.
● Blackwater is the main source of organics and nutrients in domestic wastewater. ● Various treatment methods can be applied for resource recovery from blackwater. ● Blackwater treatment systems of high integration and efficiency are the future trend. ● More research is needed for the practical use of blackwater treatment systems. Blackwater (BW), consisting of feces, urine, flushing water and toilet paper, makes up an important portion of domestic wastewater. The improper disposal of BW may lead to environmental pollution and disease transmission, threatening the sustainable development of the world. Rich in nutrients and organic matter, BW could be treated for resource recovery and reuse through various approaches. Aimed at providing guidance for the future development of BW treatment and resource recovery, this paper presented a literature review of BWs produced in different countries and types of toilets, including their physiochemical characteristics, and current treatment and resource recovery strategies. The degradation and utilization of carbon (C), nitrogen (N) and phosphorus (P) within BW are underlined. The performance of different systems was classified and summarized. Among all the treating systems, biological and ecological systems have been long and widely applied for BW treatment, showing their universality and operability in nutrients and energy recovery, but they are either slow or ineffective in removal of some refractory pollutants. Novel processes, especially advanced oxidation processes (AOPs), are becoming increasingly extensively studied in BW treatment because of their high efficiency, especially for the removal of micropollutants and pathogens. This review could serve as an instructive guidance for the design and optimization of BW treatment technologies, aiming to help in the fulfilment of sustainable human excreta management.  相似文献   
919.
船用燃油超标识别方法的建立和技术发展是进行船舶排放控制区(Domestic Emission Control Areas,DECA)政策执行的重要保障.本研究建立了基于船舶自动识别系统(Automatic Identification System,AIS)数据的船舶排放实时计算模型和岸基环境观测相结合的技术方法,选取...  相似文献   
920.
Fetal trophoblasts can be found in maternal circulation from an early stage of pregnancy and thus provide a potential source of DNA for non-invasive prenatal diagnosis. We have developed a two-step method for trophoblast isolation between the 8th and 12th week of pregnancy. Blood was sampled from 14 women undergoing termination of pregnancy or spontaneous abortion. Immunomagnetic beads precoated with HLA class I and II, and with anti-cytokeratin-18 monoclonal antibodies, were used to remove CD8+ and other maternal cells, and to select for fetal trophoblasts, respectively. Microsatellite analysis was performed on DNA extracted from the isolated, maternal, paternal and placental cells after PCR amplification. Recovery of the trophoblasts was confirmed in 13/14 cases (93%) by the identification of an identical microsatellite pattern for fetal and placental cells. Further evidence was the presence of heterozygous alleles of both maternal and paternal origin. The correct prediction of gender in all five male fetuses was an additional confirmation of trophoblast recovery. We conclude that trophoblasts can be effectively isolated from maternal blood in the first trimester, and by using polymorphic microsatellite markers to confirm sample purity, this method has potential future application in prenatal diagnosis. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
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