Cd~(2+)和Pb~(2+)对四环素超声降解性能的影响

通过紫外分光光度法,研究了Cd2+和Pb2+对四环素超声降解过程的影响。研究结果表明,Cd2+和Pb2+在水中与四环素发生络合反应后,在紫外光谱上发生蓝移,在206 nm处产生新的峰值。同时,在低摩尔比(四环素∶重金属1)时,Cd2+和Pb2+可以加快四环素的超声降解。0.01 mmol/L四环素溶液24 h的超声降解率为7.54%,加入Pb2+和Cd2+离子后,四环素去除率分别升高至20.82%和18.75%。在高摩尔比(四环素∶重金属2)时,Cd2+和Pb2+抑制了四环素的降解,在0.08 mmol/L四环素溶液中,加入Pb2+和Cd2+离子反而使四环素去除率从4.69%分别降低至2.04%和1.40%。     

Estimating health damage cost from secondary sulfate particles--a case study of Hunan Province, China

IntroductionChina’senergyusepattern ,characterizedbyadominatingrelianceoncoal,hasledtosevereSO2pollutionandresultinghealthdamage .Withconsumptionsoffossilfuelsstilltogrow ,totalhealthdamageisanticipatedtoincrease ,whichwillbeagreatchallengetoChina.Thischallengerequirescomprehensivehealthimpactassessmenttoguideenvironmentalpolicyandreorientpublicopinioninfavorofeffectivepreventiveaction .Generally,the“ImpactPathwayApproach”(Krewit,1 999;Thanh ,2 0 0 0 ) ,whichlinkstheemissiontoconcentrat…     

Field measurements of dissociation of ammonium nitrate at a Beijing site

The atmospheric nitric acid, ammonia and ammonium nitrate aerosol was determined simultaneously in a Beijing site to teste quilibrium. Rather good agreement between measurements and theory was found at ambient temperature above 9oC at relative humidity below 70%. Below 9oC the kinetic constraints preventing rapid attainment equilibrium were observed. A procedure for calculation of dependence of NH4NO3 aerosol dissociation constants on temperature and relative humidity was given. The seasonal variation of concentration of NH3, total NH4+ and HNO3 was observed.The seasonal variation of concentration of HNO3 was caused by dissociation of aerosol of NH4NO3. The concentrations of NH3 were 1-2 order higher than those of HNO3. For formation of NH4NO3 aerosol the HNO3 was the control reagent. Any increase of HNO3 to formed from NOx would react with NH3 form NH4NO3 aerosol in Beijing area except for someday in summer time.     

Urban environmental problems transition and environmental education towards sustainable cities in China

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我国电子废弃物收集体系构想

解决中国电子废弃物问题，一是控制电子废弃物进入非正式循环利用者手中；二是把非正式循环利用系统纳入良好的电子废弃物管理系统，使之成为更有效和对环境友好的系统。因此，如何把千家万户废弃的电子废弃物有效收集起来，是关系到电子废弃物管理和循环利用的重要环节。在我国建立良好的电子废弃物收集体系，应以市场经济和目前我国“城乡二元经济”为基础，建立具有收集主体多元化、收集方式多样化，收集途径多渠道等特点的电子废弃物收集体系。     

大兴安岭地震带中强地震活动的相关性及趋势预测

本文通过对大兴安岭地震带中强地震前，远近地震活动的相关性进行研究，为大兴安岭地震带中长期地震预报进行判定。     

世界自然遗产─武陵源

武陵源，位于湖南省西北部张家界市与慈利县、桑植县交界处，方圆３６９ｋｍ~２，由张家界、天子山、索溪峪、杨家界、茅岩河、九天洞、天门山等景区组成。１９８２年，张家界被命名为我国第一个国家森林公园。１９９２年，武陵源（主要包括张家界、天子山、索溪峪）被联合国教科文组织作为世界著名的旅游胜地列入世界自然遗产名录。     

德国发展环境保护的举措与实效

德国政府在改善生态环境，治理环境污染方面采取了一系列行之有效的措施。通过对大气、水源、噪声、废物等污染源的治理，改善了人们的生存环境；行政手段与经济手段并举，加快了产业结构的调整和能源结构的升级，为德国社会和经济的可持续发展奠定了基础。     

塔北、塔中天然气中CO_2的碳同位素组成及成因探讨

CO2 是塔北、塔中天然气中常见的非烃组分。各油气区内的天然气中CO2 的δ13C值尽管有差别 ,但其表征的成因意义基本一致。塔中天然气中的CO2 可能存在两种来源 ,一种来源于烃源岩岩石和矿物及胶结物分解 ;第二种来自二叠纪火山活动过程中的脱气。轮台凸起构造单元上油气藏 (除雅克拉外 )中CO2来自库车坳陷T -J陆相烃源岩中有机质转化。东河塘天然气中CO2 来自寒武 -奥陶海相碳酸盐岩岩石分解及泥岩中碳酸盐矿物分解     

Sulfur dioxide-hydrogen peroxide relationships and acidification of precipitation in Guiyang area-a case study

-The concentrations of gas phase SO2, O3 and chemical composition of sequential rainwater samples were measured on 6/11/88 to 6/28/88 at some sites of Guiyang area. S (IV) was present in great excess of H2O2 in rainwater samples collected at residential sites of the city corresponding to high level of gas phase SO2. Considerable H2O2 in rainwater samples was observed in background air at suburbs. The evidence that clean rainwater samples were collected at 20km away from the city in 6/18/88 precipitation event revealed that the major process of acidification of the rain in the high polluted areas was below-cloud scavenging of trace gases. From a simulation calculation it was found that the rate of oxidation of S(IV) by O3 and by Mn2+, Fe3+ catalytic in high pH rainwater is significant, but for low pH the major SO42- is produced by the reaction of S (IV) with H2O2.