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61.
新型聚合铝硅混凝剂处理洗浴废水的试验研究   总被引:1,自引:0,他引:1  
针对常规铝盐、铁盐去除洗浴废水中阴离子洗涤剂 (LAS)效果不理想的状况 ,采用高碱化度钙型聚合铝硅混凝剂 (CPASC)进行了试验研究 ,同时与聚合氯化铝 (PAC)作了比较。结果表明 ,该混凝剂对洗浴废水中COD、LAS、SS及浊度都有较高的去除率 ,特别对LAS、COD的去除率分别比PAC高 10 %和 8%以上。当投加量为 6 0mg/L时 ,出水各项指标均达到生活杂用水水质标准 (GJ2 5 .1 89)。  相似文献   
62.
China has announced plans to stabilize its pesticide use by 2020. Yet, future climate change will possibly increase the difficulty of meeting this goal. This study uses econometric estimation to explore how climate impacts Chinese pesticide usage and subsequently to project the future implications of climate change on pesticide use. The results indicate that both atmospheric temperature and precipitation increase pesticide usage. Under current climate change projections, pesticide usage will rise by +1.1 to 2.5% by 2040, +2.4 to 9.1% by 2070, and +2.6 to 18.3% by 2100. Linearly extrapolating the results to 2020 yields an approximately 0.5 to 1.2% increase. Thus, to achieve stabilization, more severe actions are needed to address this increase. Possible actions to achieve the reductions needed include using better monitoring and early warning networks so as to permit early responses to climate change-stimulated increases, enhancing information dissemination, altering crop mix, and promoting nonchemical control means. Additionally, given that increased pesticide usage generally increases health and environmental damage, there may be a need to more widely disseminate safe application procedure information while also strengthening compliance with food safety regulations. Furthermore, pest control strategies will need to be capable of evolving as climate change proceeds. Globally, efforts could be made to (1) scale up agrometeorological services, especially in developing countries; (2) use international frameworks to better align the environmental and health standards in developing countries with those in developed countries; and (3) adapt integrated pest management practices to climate change, especially for fruits and vegetables.  相似文献   
63.
废弃印刷线路板资源化处理的研究进展   总被引:7,自引:2,他引:7  
介绍了当前废弃印刷线路板资源化处理的主要方法,包括湿法、火法、机械法、生物法、超临界流体法和等离子体熔炼法等。综述了各种处理方法的侧重点及利弊;提出热解法与机械法联用可较好地解决在破碎过程中所遇到的问题,具有较大优势,可作为未来大量废弃印刷线路板资源化处理工艺研究的重点。  相似文献   
64.
65.
利用2014年广东南岭背景站、天湖郊区站、磨碟沙城区站和受体区域桃源站SO2、NO2、PM10、O3、PM2.5与CO自动监测数据,分析不同环境大气污染特性。结果表明,4个站点的SO2、NO2、PM10与CO整体平均年均值较低,分别为14,28,59μg/m3和0.7 mg/m3;PM2.5整体平均值为36μg/m3,O3日最大8 h第90百分位数平均值为172μg/m3,二者高于国家二级标准限值。磨碟沙城区站和桃源站的污染物日变化规律较为明显,NO2、PM10和PM2.5在早晚交通高峰或紧接其后的时段出现峰值区。南岭背景站PM2.5质量浓度日间略高于夜间;O3未呈典型单峰分布,而是维持在较平稳、较高浓度水平。周末与工作日O3平均值的相对高低多与NO2、PM10和PM2.5的情况相反。4个站点O3日最大8 h值第90百分位数均未达标;南岭背景站和天湖郊区站O3值尤高,除10月外,在1月或6月也易出现O3高值。区域性的O3污染控制亟须深化开展。  相似文献   
66.
李勇  栾辉 《油气田环境保护》2011,21(3):11-12,35
文章阐述了我国污染源在线监控系统的建设现状,论述了系统在建设、运行与管理等方面存在的问题,如污染源在线监控系统后期运行缺乏保障、仪器设备的性能与安装缺乏统一标准、技术评价体系滞后、数据采集系统协议不够统一、运行与管理人员缺乏相应培训与考核;提出了相应的对策与建议,如建立、健全相关技术标准与规范,制定统一的、广泛使用的数据采集协议,加强技术与管理人员的培训等。  相似文献   
67.
Climate change strongly affected the structure and functions of natural ecosystems,e.g.the vegetation productivity decreased in the Northeast permafrost region due to the higher temperature and less precipitation,whereas in the Tibetan Plateau,the vegetation productivity increased,owing to the improved thermal resource.Climate change led to reduced precipitation in North and Northeast China and thus the reduced surface runoff.The public needs for energy were changed because of climate change,e.g.the shorter heating period in winter.Climate change profoundly influenced human health,pathophoresis and major projects by increasing extreme events,including frequency and magnitude,and causing more serious water shortage.Under the background of climate change,although the improved thermal resources can be helpful for extending the crop growth period,more extreme events may resulted in more instability in agricultural productivity.Not only did climate change indirectly affect the secondary and tertiary industries through the impacts on agriculture and natural resources,but also climate change mitigation measures,such as carbon tax,tariff and trading,had extensive and profound influences on the socioeconomic system.Further analysis indicated that the impact of climate change presented significant regional differences.The impact had its pros and cons,while the advantages outweighed the disadvantages.Based on the above analysis on the impacts of climate change,we put forward suggestions on coping with climate change.First,scientifically dealing with climate change will need to seek advantages while avoiding the disadvantages of climate change in order to achieve the orderly adaptation to climate change,which is characterized with"Overall best,long-term benefit."Second,quantitative adaptation should be given more attention,e.g.proposing operational schemes and predictable goals and using uncertainty analysis on adaptation measures.Third,more active coping strategy should be adopted to enhance China's future comprehensive competitiveness.The strategies include but are not limited to gradually adjusting the industrial structure,intensifying the research and development(RD)of emission reduction technology and actively responding to the influence of carbon tax,tariff and trading on socioeconomic development in China.  相似文献   
68.
Lau MC  Chan KM  Leung KM  Luan TG  Yang MS  Qiu JW 《Chemosphere》2007,69(1):135-144
Experiments were performed to determine the acute and chronic toxicities of tributyltin (TBT) (nominal concentrations) to polychaete Hydroides elegans. Firstly, static tests were performed to examine the lethal effect of TBT on five life stages of H. elegans. The 48-h LC(50) (95% CI) for the eggs, 2-cells, trochophores, juveniles and adults was 0.18 (0.15-0.20), 0.97 (0.77-1.23), 2.36 (2.11-2.65), 2.86 (2.63-3.12) and 4.36 (4.04-4.71) microg TBT l(-1), respectively. Secondly, a 17-d static renewal chronic test was conducted to study sensitivity of the early development (egg to juvenile) to TBT. The survivorship, percent settlement and time to reach settlement were significantly reduced at 0.01 microg TBT l(-1). Effects of TBT on the juvenile growth and maturation were also studied through a 44-d chronic test. Lower survivorship and reduced tube growth were observed only at >or= 1 microg TBT l(-1), however, only H. elegans exposed to or= 0.1 microg TBT l(-1). Our results indicate that the early development of H. elegans is highly sensitive to TBT and this polychaete can be routinely employed as a test organism for both acute and chronic ecotoxicity bioassays in tropical and subtropical regions such as southern China.  相似文献   
69.
OBJECTIVES: The majority of motor vehicle occupants who were killed or hospitalized in crashes in Kentucky in 2000-2001 occupied vehicles that were severely damaged in the crash. Even so, overall only a small percentage of all severely damaged vehicle occupants were killed or hospitalized. The purpose was to identify occupant, vehicle, crash, and roadway/environmental factors that were associated with increased risk of severe injury in crashes where the occupant's vehicle was severely damaged. METHODS: This study probabilistically linked Kentucky's statewide motor vehicle crash and inpatient hospital discharge data files for 2000 and 2001, and selected cases representing occupants of vehicles that were reported by police as having either "severe" or "very severe" damage. For occupants who were identified through data linkage as having been hospitalized, the Injury Severity Score (ISS) was calculated using ICDMAP-90 software, and the scores were stratified into the following categories: critical (>24), severe (15-24), moderate (9-14), and mild (<9). We then created an outcome variable, injury severity level, with five levels: killed; hospitalized with at least moderate injuries (ISS = critical, severe, or moderate); hospitalized with mild injuries (ISS = mild); injured according to the police report but not hospitalized; and no apparent injury according to the police report. We performed a stepwise, ordinal logistic regression of injury severity, using independent variables identified from the existing crash literature. RESULTS: Occupant risk factors for higher levels of injury severity selected by the regression were age (risk increased with age, other factors being equal), female gender, restraint non-use, ejection from the vehicle, and driver impairment (by alcohol and/or drugs). Crash risk factors included head-on collision, collision with a fixed object, vehicle rollover, and vehicle fire. Roadway/environmental factors were federal- or state-maintained roadway and posted speed limit 89 kph (55 mph) or greater. CONCLUSIONS: Many of the identified risk factors are explicitly or implicitly mentioned in the strategic plans of key organizations involved in highway safety and injury prevention in Kentucky. Our analysis provides additional evidence of their importance, and confirms that their mitigation will reduce injury severity in crashes involving severe vehicle damage. Additionally, older occupants and female occupants showed increased risks of serious injury, but to our knowledge these factors are not currently addressed in any state plans. An opportunity exists to clarify the nature of these risks through further studies, which might lead to the identification of countermeasures specific to these populations.  相似文献   
70.
以ZSM-5分子筛粉体为原料,成型后负载铜盐和有机胺改性,制备出一种高效脱除氮氧化物的吸附剂。通过改变铜盐、有机胺的含量以及铜盐活化温度使吸附剂的性能得到优化,在实验条件下(NO:初浓度1000mg/m^3,气流2.7L/min)床层对NO2动态吸附的透过时间由改性前的3min提高到90min,并使NO气体的释放得到有效减缓。通过动态吸附实验研究了NO释放时间在负载前后的变化,通过X射线光电子能谱(XPS)和红外分析(FTIR)研究了吸附剂表面铜元素、有机基团等在吸附前后的变化规律,提出了可能的净化机理。  相似文献   
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