北京市冬季气溶胶粒子尺度谱分布研究

对2000年12月和1980年代中期北京市近地面气溶胶尺度谱的观测数据,进行了分析和比较研究.结果表明,在粒子尺度谱上,粒子分布向更细粒子位移;0.1～2.0 μm的积聚模态粒子,其峰中心在0.12 μm处.在粒子体积(质量)尺度谱上,粒径小于2 μm的细粒子约占26.9%,粗粒子约占73.1%,表现出细粒子浓度增加的趋势.气溶胶发生源结构的变化,使原生粒子减少,再生粒子增加.这部分粒子对人的危害更大,更难于治理.     

Prediction of the concentration of chlorophyll-a for Liuhai urban lakes in Beijing City

The weekly water quality monitor data of Liuhai lakes between April 2003 and November 2004 in Beijing City were used as an example to build an artificial neural networks （ANN） model and a multi-varieties regression model respectively for predicting the fresh water algae bloom. The different predicted abilities of the two methods in Liuhai lakes were compared. A principle analysis method was first used to select the input variables of the models to avoid the phenomenon of collinearity in the data. The results showed that the input variables for the artificial neural networks were T, TP, transparency（SD）, DO, chlorophyll-a （Chl-a）,pH and the output variable was Chl-a. A three layer Levenberg-Marguardt feed forward leaming algorithm in ANN was used to model the eutrophication process of Liuhai lakes. 20 nodes in hidden layer and 1 node of output for the ANN model had been optimized by trial and error method. A sensitivity analysis of the input variables was performed to evaluate their relative significance in determining the predicted values. The correlation coefficient between predicted value and observed value in all data and in test data were 0.717 and 0.816 respectively in the artificial neural networks. The stepwise regression method was used to simulate the linear relation between Chl-a and temperature, of which the correlation coefficient was 0.213. By comparing the results of the two models, it was found that neural network models were able to simulate non-linear behavior in the water eutrophication process of Liuhai lakes reasonably and could successfully estimate some extreme values from calibration and test data sets.     

九月絮语

2008年8月8日，北京奥运会，中国人以51金高居榜首。随之而来的残奥会，中国人再次以89金211枚奖牌蝉联第一。科技之光大放异彩，新成果、新技术的应用，使我们灿烂的文化备受瞩目。然而，人们没有沾沾自喜，却陷入思考，为什么我们的开幕式转播乏味、无趣，同外的剪辑却美轮美奂、令人震撼？张艺谋导演的开幕式到底是一场投资巨大的好莱坞烂片还是中国传统文化的完美展示？     

低碳生活 从细节开始——访北京环境交易所董事长熊焰

对话人物：熊焰。现任北京环境交易所董事长，北京产权交易所总裁，同时兼任中国并购公会发起人理事、第三届轮值主席，北京PE协会副会长兼秘书长，亚洲资本论坛永久理事。亚杰商会执委等多个社会职务，并被哈尔滨工业大学、中央党校、清华大学、中央财经大学聘为兼职教授。     

亚欧首脑会议发表《可持续发展北京宣言》

2008年10月24—25日，亚洲16国和欧洲27国的国家元首、政府首脑以及欧盟委员会主席和东盟秘书长齐聚北京，在第七届亚欧首脑会议上共同发布了《可持续发展北京宣言》。     

国家督导组充分肯定我省秸秆禁烧工作

国家秸秆禁烧督导组对我省秸秆禁烧工作给予充分肯定，认为河北秸秆禁烧工作扎实，措施有力。同时要求，继续堵疏结合，严防死守，以确保北京奥运会良好的空气质量。     

护佑奥运蓝天白云—河北准备好了

"专家称,随着北京空气质量的不断改善,奥运期间.不会因为北京空气 质量损害运动员身体健康或者影响他们 水平的发挥."     

14369辆

从7月1日北京实施交通限行措施至8月10日，北京市环保、交管与城管等部门共查处违规车辆5万多辆，其中本市车辆违反单双号限行的有14369辆，黄标车违规上路车辆15234万辆。同时，由于无统一绿色环保标志和证明，有16117外地车辆被劝返，违反单双号限行车辆被劝返的有946辆，还有774辆尾气超标车辆被劝返。     

创建绿色奥运 营造绿色环境

环境治理的总体进展如何 樊元生:今年以来,在党中央、国务院的正确领导下,全国环保系统深入贯彻落实科学发展观,加强环境监管和环境应急工作,确保灾区环境安全;把污染减排作为一项重要任务,采取综合措施,加快污染治理,环保工作取得积极进展.