疏水改性阳离子聚丙烯酰胺絮凝剂的制备及其絮凝性能

通过水溶液共聚合法,以丙烯酰胺(AM)、丙烯酰氧乙基三甲基氯化铵(DAC)和2-乙烯基吡啶(2-VP)为共聚单体合成了疏水改性阳离子聚丙烯酰胺P(AM-DAC-2VP),并用红外光谱仪和核磁共振光谱仪对其结构进行了表征。实验结果表明:当w(2-VP)为1.0%、w(DAC)为30%、活性污泥pH为5、P(AM-DAC-2VP)加入量为25mg/L时,P(AM-DAC-2VP)对本实验的活性污泥絮凝能力最强,上清液透光率为92.1%;P(AM-DAC-2VP)比同条件下制备的阳离子聚丙烯酰胺P(AM-DAC)具有更好的絮凝效果。     

Bio-immobilization of Cu and Zn in recirculated bioreactor landfill

Purpose  

To protect the environmental quality of soil, groundwater, and surface water near the landfill site, it is necessary to make an accurate assessment of the heavy metal mobility. This study aims to present the bio-immobilization behavior of heavy metals in landfill and provide some reference suggestion for the manipulation of heavy metal pollution control after closure.     

废弃中药渣催化热解制取生物油的研究

利用热重分析仪(TGA)对植物类中药渣的热解特性进行了研究,用Coats-Redfern积分法计算了其热解动力学参数,得出中药渣热解反应符合一级反应动力学方程,其活化能较低,为36.0kJ/mol。考察了热解温度对气体、液体、固体产物的影响,在723K时,液体产物生物油产率最高,为39%。以介孔分子筛SBA-15以及分别负载Al、Sn、Ni、Cu和Mg的SBA-15作为催化剂,研究催化热解对气体、液体、固体产率及生物油组分的影响。研究表明,Al-SBA-15的催化效果较好,液体产率最高,为36%;采用元素分析仪和热值测定仪,得到用Al-SBA-15作为催化剂时生物油的氧质量分数最低,低位热值最高。用GC/MS对生物油组分的分析结果表明,添加Al-SBA-15后,热解产物中脂肪族和芳香族化合物增加,而含氧化合物减少。     

The crude oil market and the gold market: Evidence for cointegration,causality and price discovery

Given that the gold market and the crude oil market are the main representatives of the large commodity markets, it is of crucial practical significance to analyze their cointegration relationship and causality, and investigate their respective contribution, from the perspective of price discovery, to the common price trend so as to interpret the dynamics of the whole large commodity market and forecast the fluctuation of crude oil and gold prices.     

莱特生物强化技术处理高浓度有机废水的中试

采用莱特生物强化技术(LTBR—Littoral BioReactor),对兰州石化公司化工园区高浓度有机废水进行了中试试验,进行了正常运行的常规标定、水量冲击标定、浓度冲击标定。结果表明:采用LTBR生物处理工艺,使用特效微生物和营养基质,可以在高COD、高含盐等不利条件下正常进行有机物降解,达到了必须将废水中的COD降至2000mg/L以下的试验要求,为处理高浓度有机化工废水的工程应用开辟了新思路。     

广元实现科学重建的必由之路:发展低碳经济

低碳经济是指在可持续发展理念指导下,通过技术创新、制度创新、产业转型、新能源开发等多种手段,尽可能地减少煤炭、石油等高碳能源消耗,减少温室气体排放,达到经济社会发展与生态环境保护双赢的一种经济发展形态。坚持以能源结构低碳化、产业发展低碳化和生态建设为主线,大力推进经济社会低碳恢复、低碳重建、低碳发展,全力打造低碳项目投资"洼地",努力把广元市建设成国家森林城市、国家生态宜居城市和全国低碳发展示范城市。     

衡水市医疗废物处理现状调查及对策

医疗废物是一类成分复杂并有特殊危害的危险废弃物。通过分析衡水市医疗废物处理过程中存在的分散处置、处理率低等问题,提出了加强管理监督机制、提高医疗废物收集处理率的应对策略。通过综合比较分析几种医疗废物处理方法的优缺点,指出高温焚烧法集中处置是衡水市医疗废物的最佳处理方法。     

Measurements of ultrafine particles and other vehicular pollutants inside school buses in South Texas

Increasing evidence has demonstrated toxic effects of vehicular emitted ultrafine particles (UFPs, diameter < 100 nm), with the highest human exposure usually occurring on and near roadways. Children are particularly at risk due to immature respiratory systems and faster breathing rates. In this study, children’s exposure to in-cabin air pollutants, especially UFPs, was measured inside four diesel-powered school buses. Two 1990 and two 2006 model year diesel-powered school buses were selected to represent the age extremes of school buses in service. Each bus was driven on two routine bus runs to study school children’s exposure under different transportation conditions in South Texas. The number concentration and size distribution of UFPs, total particle number concentration, PM_2.5, PM₁₀, black carbon (BC), CO, and CO₂ levels were monitored inside the buses. The average total particle number concentrations observed inside the school buses ranged from 7.3 × 10³ to 3.4 × 10⁴ particles cm^?3, depending on engine age and window position. When the windows were closed, the in-cabin air pollutants were more likely due to the school buses’ self-pollution. The 1990 model year school buses demonstrated much higher air pollutant concentrations than the 2006 model year ones. When the windows were open, the majority of in-cabin air pollutants came from the outside roadway environment with similar pollutant levels observed regardless of engine ages. The highest average UFP concentration was observed at a bus transfer station where approximately 27 idling school buses were queued to load or unload students. Starting-up and idling generated higher air pollutant levels than the driving state. Higher in-cabin air pollutant concentrations were observed when more students were on board.     

Zr—Fe双组分复合除砷吸附剂的优化制备及性能评价

实验发现,铁氧化物或铁的羟基氧化物对As（V）有较好的吸附性能,而锆氧化物或锆水合氧化物则对As（Ⅲ）有优异的吸附选择性,但其使用的pH通常要在〉9的条件下。通过简单的共沉淀法制备了Zr-Fe双组分复合吸附剂,在制备过程中通过优化制备条件如：沉淀剂浓度、金属离子总浓度、金属离子配比、反应温度、反应时间及吸附剂价格等因素,最终合成出了对As（V）和As（Ⅲ）都具有良好吸附能力的吸附剂。这种吸附剂在中性条件下对As（V）和As（Ⅲ）的最大吸附量为62mg／g和118mg／g。     

Ambient TSP concentration and dustfall in major cities of China: Spatial distribution and temporal variability

Based on environmental monitoring data in 93 major cities and meteorological records at 398 weather stations in China from 1981 to 2007, total suspended particle (TSP) concentration, the intensity of dustfall, and sand and dust storm frequency (F_d) were analysed. During the past 27 years, the annual average TSP concentration (C_TSP) in 93 cities was 402 μg m^?3. Annual average C_TSP decreased from the north to the south and from inland to the coast areas with a peak value of 628.8 μg m^?3 in Lanzhou. In the 1980s, 1990s and 2000s, annual average C_TSP was 628.7, 319.2, and 250.1 μg m^?3, respectively. Annual average intensity of dustfall (I_d) was 240.5 t km^?2 a^?1, decreased from northern to southern China and from inland to the coast areas with the maximum value of 717.2 t km^?2 a^?1 in Baotou. In the 1980s, 1990s and 2000s, annual average I_d was 334.8, 220.9, 146 t km^?2 a^?1 respectively. Annual average I_d in the Loess Plateau region was commonly higher than 200 t km^?2 a^?1. The annual average F_d decreased from arid regions in northwestern China to humid areas in southeastern China with two sand and sand storm centers existing in Xinjiang Taklamakan Desert and western Inner Mongolia. The annual average F_d in the 1980s, 1990s, 2000s was 16, 8, 6 days respectively, decreased steadily from 18 days in 1981–5 days in 2007. Annual average I_d had a positive linear relation to annual average C_TSP (R² = 0.96). Annual average F_d had a positive relation with annual average C_TSP (R² = 0.97) as well as annual average I_d (R² = 0.94). TSP was the chief pollutant influencing Air Pollution Index (API) in northern China in spring and winter seasons. Sand and dust storm might be a major factor affecting the temporal variability and spatial distribution of TSP and dustfall in China.