双碱法烟气脱硫技术影响因素分析

双碱法在中小型燃煤锅炉的烟气脱硫上有着较广泛的应用,它克服了其他湿法脱硫容易结垢的缺点,且脱硫效率高。主要介绍近几年国内双碱法烟气脱硫效率主要影响因素的理论和实验研究现状,分析了pH值、钠离子浓度、液气比、硫酸根离子的比例和进口二氧化硫浓度等因素对该技术的脱硫效果的影响,提出了该技术目前存在的问题及其今后的发展方向。     

衡阳市降水型地质灾害潜势预报预警方法初探

为提高衡阳市降水型地质灾害预报预警的针对性和时效性,本文利用1994—2007年衡阳市地质灾害个例资料和相应的降水资料,分析了地质灾害与降水的关系;划分了地质灾害易发区,并针对不同易发区确定了降水型地质灾害预报预警指标;对预报预警方法进行检验,并提出了改善建议。结果显示:衡阳市降水型地质灾害与前期降水强度、当日降水量等有着密切关系;建立的预报预警方法对衡阳市暴雨突发性地质灾害预报具有较好的地域针对性和准确性,将预报时效延长至24小时,对地质灾害的防御有着重要的现实意义。     

Bioaccumulation of heavy metals by Phragmites australis cultivated in synthesized substrates

Accumulation of heavy metals from various oxides with adsorbed cadmium by wetland plant Phragmites australis was studied to evaluate the fate of heavy metals in the sediment of constructed wetlands. Hoagland solution was used as nutrition supply, and single metal oxide with adsorbed cadmium was applied as contaminant to study the accumulation characteristics of cadmium and the substrate metals by P. australis. After 45-d treatment, the bioaccumulation degree in root followed the order: Al(OH)₃ > Al₂O₃ > Fe₃O₄ > MnO₂ > FeOOH. Heavy metals absorbed by P. australis were largely immobilized by the roots with little translocation to aboveground parts.     

滦河锡林郭勒盟段水质状况评价

利用水质指数法对滦河锡林郭勒盟段水质状况进行了分析评价,结果显示：（1）滦河锡林郭勒段2005-2007年主要污染因子为：高锰酸盐指数、化学需氧量、铁、生物需氧量、锰、总磷等;（2）2005-2007年间,上都河监测断面水质状况整体呈变好趋势,但地方经济增长带来的化学需氧量异常升高不容忽视,大河口断面不同水期水质状况变化不同;（3）2005-2007年,滦河锡林郭勒段化学需氧量与溶解氧超标污染加重明显、高锰酸盐指数超标污染逐渐减轻;三年内,上游水质均优于下游水质,两个监测断面水质均为丰水期水质〈平水期水质〈枯水期水质。     

Bioaccumulation of cadmium bound to humic acid by the bivalve Meretrix meretirx Linnaeus from solute and particulate pathways

Humic acid is an important pool of heavy metals in sediments.Generally,the presence of refractory humic matter in aquatic systems would decrease the bioavailability of Cd and hence control the bioaccumulation of Cd in benthic animals.In the present work,we applied a suspending system to determine the relative importance of particulate and dissolved fractions of humic acid as Cd sources for the bivalve Meretrix meretrix and to investigate the difference of bioaccumulation characteristics of Cd adsorbed on di...     

为什么我不买iPhone

<正>8月份,中国又不出意料地拿下了两项最新世界排名,先是8月16日日本公布的二季度数据表明,今年中国GDP已经铁定超过日本,成为世界第二大经济体;25日,云南华能小湾水电站4号机组投产后,中国水电的装机容量又正式跃居世界第一。排名上升后,中国     

Do land utilization patterns a ect methanotrophic communities in a Chinese upland red soil?

Soil samples were collected from three plots under di erent land utilization patterns including degradation, farming, and restoration. The abundances of methanotrophs were quantified using real-time polymerase chain reaction (PCR) based on the pmoA and 16S rRNA genes, and the community fingerprint was analyzed using denaturing gradient gel electrophoresis (DGGE) aiming at pmoA gene. Significantly lower 16S rRNA and pmoA genes copies were found in the degradation treatment than in farming and restoration. Higher abundances of Type I than those of Type II methanotrophs were detected in all treatments. The treatment of farming was clearly separated from degradation and restoration according to the DGGE profile by cluster analysis. The lowest diversity indices were observed in the F (farming plot), suggesting that the community structure was strongly a ected by farming activities. There were significantly positive correlations between the copy numbers of pmoA also Type II-related 16S rRNA genes and soil available K content. Strong negative and positive correlations were found between Type I and soil pH, and available P content, respectively. We concluded that the vegetation cover or not, soil characteristics including pH and nutrients of P and K as a result of anthropogenic disturbance may be key factors a ecting methanotrophic communities in upland soil.     

温度对好氧颗粒污泥吸附铅离子的影响

由活性污泥培养得到好氧颗粒污泥,研究了温度对好氧颗粒污泥吸附Pb²⁺的影响.结果表明,好氧颗粒污泥主要含有C、H、N、O、P等元素,其经验结构式为C_5.7H_10.9O3.9NS_0.04.好氧颗粒污泥表面主要由球状细菌组成,具有明显的孔隙结构.在20～40℃时,Pb²⁺在好氧颗粒污泥上的吸附过程可以由Langmuir和Freundlich等温方程进行拟合（R²>0.914）.Pb2+最大吸附量Qmax由80.65 mg·g-1（20℃）增至97.09　mg·g-1（40℃）.吸附过程的表观自由能变ΔG<0、 ΔH>0、 ΔS>0,表明Pb2+在好氧颗粒污泥表面的吸附为吸热、熵增的自发过程.红外扫描分析(FTIR)结果表明,吸附过程Pb2+主要与—OH、蛋白质中的—COOH以及PO发生作用,与含氮官能团无关.     

加速吉林省国界河流网络环境监测站标准化建设的建议

本文通过对吉林省国界河流水质状况分析,对其网络环境监测站的监测能力、监测设备等基本情况进行了调查,提出了加速基层网络环境监测站的标准化建设的建议。