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1.
全球变暖对上海和广州人群死亡数的可能影响   总被引:9,自引:0,他引:9  
研究表明,最高气温达到34℃以上的“热日”死亡数显著增加,“热日多出死亡数”占夏季总死亡数的百分率,上海为4.2%,广州为3.8%。广州人对热压力的适应性比上海人强。如果上海和广州未来温升不到1℃,冬夏死亡效变化不大;如温升几度,夏季死亡数上升,超过冬季死亡数的下降,全年死亡率增高。  相似文献   

2.
室内空气中的氡可能引起10%肺癌死亡率美国国立癌症研究院的IayH.Lubin和他的合作者,将在轴矿矿工中肺癌研究的结果外推后估计所有肺癌死亡数的10%,即每年15,000人至少与暴露于室内氡有关。研究人员估计非吸烟人员肺癌死亡数的30%可能由氡引起...  相似文献   

3.
江镕 《环境》2012,(9):6-8
2012年6月30日晚,广州突然下发“限牌令”,从7月1日起实施摇号购车政策,让广州市民始料未及。至此,广州成为继上海、北京、贵阳之后我国第四个汽车限牌城市。  相似文献   

4.
医疗废物典型组分的热重分析及新的动力学模型   总被引:6,自引:2,他引:6  
为研究医疗废物的热解失重规律和反应动力学机制,对其热失重过程进行了模拟.利用差热热重分析仪,在氮气气氛下对医疗废物的14种典型组分进行了热解实验,建立了“整体两步四反应模型”.结果显示,样品失水后,在160℃-290℃之间开始热解,次序依次为药物类、塑料类、蛋白质类、生物质类、合成纤维类和橡胶类;经过一步或两步失重,在800℃时热解基本完成.所建立的“整体两步四反应模型”能很好地描述样品的热解行为,最大相对误差为1.68%,并可以对医疗废物的热解产物进行预测.  相似文献   

5.
李云龙 《环境》2003,(12):20-21
说到热,人们马上会想到广州或海南岛,其实夏天中国最热的地方是新疆的吐鲁番盆地。很多人还不知道,这个神秘的“火洲”,还有着许多鲜为人知的“怪事”呢!  相似文献   

6.
运用Fluent软件对重庆市嘉陵江化龙桥段瑞安新天地江水水源热泵系统尾水排入受纳水域的过程进行二维数值模拟,选取Fluent中非耦合、隐式求解器对模型内的定常流动进行求解,得出受纳水域受水源热泵系统温排水影响后的温升面积和温度梯度。结果表明:在温排水流量为2.0×103 m3/h、温差为4℃的条件下,计算该水域沿水流方向温升超过1℃的最大影响距离为150.4 m,温升超过1℃的水域面积约为1 525 m2,为模拟江水面积的8.59%。选取1℃温升值作为温升带的边界控制值,并在热泵系统最大负荷工况下,根据W=Q×ΔT计算研究水域热环境容量为19.402 m3.℃/s,剩余热环境容量为17.736 m3.℃/s。根据地表水环境质量标准,该工程温排水量小于受纳水域的热承载力,不会对受纳水域生态环境造成热污染。  相似文献   

7.
为了准备接受“1973年国际防止船舶造成污染公约及其1978年议定书”,交通部1973年国际防止船舶造成污染学习研究班于82年10月5日至11月3日在上海海运学院举办。参加这期研究班的共有25人,分别来自港务监督,船检部门、港务局环办、上海、广州海运局、武汉河  相似文献   

8.
为探明当前滨海电厂冷却系统热冲击和加氯对浮游植物的影响程度,于室内对采自乐清湾的浮游植物进行短期(15、30 min)温升(0、4、8、12℃)和加氯(O、1.0、1.8、3.2 mg·L-1)胁迫的模拟研究.结果表明,加氯、暴露时间、加氯和温升间的交互作用对叶绿素a(Chl-a)浓度有显著影响(P<0.01).但温升对Chl-a浓度无显著影响(P>0.05).热冲击和加氯胁迫后.浮游植物细胞活性显著降低(P<0.05).加氯对Chl-a浓度及浮游植物细胞活性影响最大.目前,滨海电厂浓度为1-2 mg·L-1的加氯处理对浮游植物影响较大,但温升8-12℃的热冲击对浮游植物影响不大.  相似文献   

9.
由国家发改委和中央电视台共同主办的“全民节约.共同行动”主题宣传活动启动仪式上海分会场活动.8月14日在浦东陆家嘴绿地举行.上海市委副书记、市长韩正冒着酷暑出席活动并与市民进行交流。本次活动以“上海百万家庭节约活动”为主题。以社区为平台.以家庭为重点,由政府职能部门具体配合运作,集中开展形式多样的宣传、培训、咨询、展示活动。  相似文献   

10.
方芳 《环境保护》2006,(2A):18-20
以2006年为开端的“十一五”时期。是落实科学发展观的重要时期。也是我国环境保护事业深入发展的战略机遇期。对于上海而言.更是集中筹办世博会.实施“科教兴市”主战略和基本形成上海“四个中心”框架的关键阶段。因而早在2004年3月12日。上海市政府便召开了上海市“十一五”规划编制前期工作会议,正式启动了上海市“十一五”规划的编制工作。编制和实施好环境保护“十一五”规划。对于上海市滚动实施环保三年行动计划,成功举办2010年世博会.全面推进上海生态型城市建设。具有十分重大的意义。[编者按]  相似文献   

11.
Toxic effects of two agrochemicals on nifH gene in agricultural black soil were investigated using denaturing gradient gel electrophoresis (DGGE) and sequencing approaches in a microcosm experiment. Changes of soil nifH gene diversity and composition were examined following the application of acetochlor, methamidophos and their combination. Acetochlor reduced the nifH gene diversity (both in gene richness and diversity index values) and caused changes in the nifH gene composition. The effects of acetochlor on nifH gene were strengthened as the concentration of acetochlor increased. Cluster analysis of DGGE banding patterns showed that nifH gene composition which had been affected by low concentration of acetochlor (50 mg/kg) recovered firstly. Methamidophos reduced nifH gene richness that except at 4 weeks. The medium concentration of methamidophos (150 mg/kg) caused the most apparent changes in nifH gene diversity at the first week while the high concentration of methamidophos (250 mg/kg) produced prominent effects on nifH gene diversity in the following weeks. Cluster analysis showed that minimal changes of nifH gene composition were found at 1 week and maximal changes at 4 weeks. Toxic effects of acetochlor and methamidophos combination on nifH gene were also apparent. Different nifH genes (bands) responded differently to the impact of agrochemicals: four individual bands were eliminated by the application of the agrochemicals, five bands became predominant by the stimulation of the agrochemicals, and four bands showed strong resistance to the influence of the agrochemicals. Fifteen prominent bands were partially sequenced, yielding 15 different nifH sequences, which were used for phylogenetic reconstructions. All sequences were affiliated with the alpha- and beta-proteobacteria, showing higher similarity to eight different diazotrophic genera.  相似文献   

12.
The effects of arbuscular mycorrhizal (AM) fungus (Glomus mosseae) and phosphorus (P) addition (100 mg/kg soil) on arsenic (As) uptake by maize plants (Zea mays L.) from an As-contaminated soil were examined in a glasshouse experiment.Non-mycorrhizal and zero-P addition controls were included.Plant biomass and concentrations and uptake of As,P,and other nutrients,AM colonization,root lengths,and hyphal length densities were determined.The results indicated that addition of P significantly inhibited root colonization and development of extraradical mycelium.Root length and dry weight both increased markedly with mycorrhizal colonization under the zero-P treatments,but shoot and root biomass of AM plants was depressed by P application.AM fungal inoculation decreased shoot As concentrations when no P was added,and shoot and root As concentrations of AM plants increased 2.6 and 1.4 times with P addition,respectively.Shoot and root uptake of P,Mn,Cu,and Zn increased,but shoot Fe uptake decreased by 44.6%,with inoculation, when P was added.P addition reduced shoot P,Fe,Mn,Cu,and Zn uptake of AM plants,but increased root Fe and Mn uptake of the nonmycorrhizal ones.AM colonization therefore appeared to enhance plant tolerance to As in low P soil,and have some potential for the phytostabilization of As-contaminated soil,however,P application may introduce additional environmental risk by increasing soil As mobility.  相似文献   

13.
Laogang landfill near Shanghai is the largest landfill in China, and receives about 10000 t of daily garbage per day, Samples of topsoil and plants were analyzed to evaluate mercury pollution from the landfill. For topsoil samples, there were significant correlations among total mercury (HgT), combinative mercury (Hgc) and gaseous mercury (HgG), and content of total organic carbon (TOC), but, no significantly relationship was found between Hg content and filling time. Hg content changes in vertical profiles with time showed that the average Hgv of profiles 1992, 1996, and 2000 was similar, but their average HgG was quite different. HgT was significantly correlated with Hgc in profile 1992 and 2000, and Hgv was significantly correlated with Hg6 in profile 1996. HgG/Hgv ratio in profile samples decreased in the order of (HgG,/HgT)1992〉(HgG/HgT)1996〉〉(HgG/HgT)2000. A simple outline of Hg release in landfill could be drawn: with increasing of filling time, degradation undergoes different biodegradation, accordingly, gaseous mercury goes through small, more, and small proportion to total mercury. Distribution of Hg in plants was inhomogeneous, following the order of leaf〉root〉stem. The highest value of leaf may be associated with higher atmospheric Hg from landfill. Ligneous plants (e.g. Phyllostachys glanca, Prunus salicina and Ligustrum lucidum) are capable of enriching more Hg than herbaceous plants.  相似文献   

14.
Phytoremediation is a potential cleanup technology for the removal of heavy metals from contaminated soils.Bidens maximowicziana is a new Pb hyperaccumulator,which not only has remarkable tolerance to Pb but also extraordinary accumulation capacity for Pb.The maximum Pb concentration was 1509.3 mg/kg in roots and 2164.7 mg/kg in overground tissues.The Pb distribution order in the B. maximowicziana was:leaf>stem>root.The effect of amendments on phytoremediation was also studied.The mobility of soil Pb and the Pb concentrations in plants were both increased by EDTA application.Compared with CK(control check),EDTA application promoted translocation of Pb to overground parts of the plant.The Pb concentrations in overground parts of plants was increased from 24.23-680.56 mg/kg to 29.07-1905.57 mg/kg.This research demonstrated that B.maximowicziana appeared to be suitable for phytoremediation of Pb contaminated soil,especially,combination with EDTA.  相似文献   

15.
In this study an effort has been made to use plant polyphenol oxidases; potato (Solanum tuberosum) and brinjal (Solanum melongena), for the treatment of various important dyes used in textile and other industries. The ammonium sulphate fractionated enzyme preparations were used to treat a number of dyes under various experimental conditions. Majority of the treated dyes were maximally decolorized at pH 3.0. Some of the dyes were quickly decolorized whereas others were marginally decolorized. The initial first hour was sufficient for the maximum decolorization of dyes. The rate of decolorization was quite slow on long treatment of dyes. Enhancement in the dye decolorization was noticed on increasing the concentration of enzymes. The complex mixtures of dyes were treated with both preparations of polyphenol oxidases in the buffers of varying pH values. Potato polyphenol oxidase was significantly more effective in decolorizing the dyes to higher extent as compared to the enzyme obtained from brinjal polyphenol oxidase. Decolorization of dyes and their mixtures, followed by the formation of an insoluble precipitate, which could be easily removed simply by centrifugation.  相似文献   

16.
Decomposition of alachlor by ozonation and its mechanism   总被引:1,自引:0,他引:1  
Decomposition and corresponding mechanism of alachlor, an endocrine disruptor in water by ozonation were investigated. Results showed that alachlor could not be completely mineralized by ozone alone. Many intermediates and final products were formed during the process, including aromatic compounds, aliphatic carboxylic acids, and inorganic ions. In evoluting these products, some of them with weak polarity were qualitatively identified by GC-MS. The information of inorganic ions suggested that the dechlorination was the first and the fastest step in the ozonation of alachlor.  相似文献   

17.
The influence of the nonionic surfactant Tween 80 on pentachlorophenol (PCP) oxidation catalyzed by horseradish peroxidase was studied. The surfactant was tested at concentrations below and above its critical micelle concentration (CMC). Enhancement of PCP removal was observed at sub-CMCs. The presence of Tween 80 in the reaction mixture reduced enzyme inactivation which occurred through a combination of free radical attack and sorption by precipitated products. A simple first-order model was able to simulate time profiles for enzyme inactivation in the presence or absence of Tween 80. At supra-CMCs, the surfactant caused noticeable reductions in PCP removal, presumably through micelle partitioning of PCP which precluded the hydrophobic PCP molecule from interacting with the enzyme.  相似文献   

18.
RemovalofheavymetalsfromsewagesludgebylowcostingchemicalmethodandrecyclinginagricultureWuQitang,NyirandegePascasie,MoCehuiF...  相似文献   

19.
A field study was conducted in the Taihu Lake region, China in 2004 to reveal the organochlorine pesticide concentrations in soils after the ban of these substances in the year 1983. Thirteen organochlorine pesticides (OCPs) were analyzed in soils from paddy field, tree land and fallow land. Total organochlorine pesticide residues were higher in agricultural soils than in uncultivated fallow land soils. Among all the pesticides, ΣDDX (DDD, DDE and DDT) had the highest concentration for all the soil samples, ranging from 3.10 ng/g to 166.55 ng/g with a mean value of 57.04 ng/g and followed by ΣHCH, ranging from 0.73 ng/g to 60.97 ng/g with a mean value of 24.06 ng/g. Dieldrin, endrin, HCB and α-endosulfan were also found in soils with less than 15 ng/g. Ratios of p,p'-(DDD DDE)/DDT in soils under three land usages were: paddy field > tree land > fallow land, indicating that land usage inlfuenced the degradation of DDT in soils. Ratios of p,p'-(DDD DDE)/DDT >1, showing aged residues of DDTs in soils of the Taihu Lake region. The results were discussed with data from a former study that showed very low actual concentrations of HCH and DDT in soils in the Taihu Lake region, but according to the chemical half-lives and their concentrations in soils in 1980s, the concentration of DDT in soils seemed to be underestimated. In any case our data show that the ban on the use of HCH and DDT resulted in a tremendous reduction of these pesticide residues in soils, but there are still high amounts of pesticide residues in soils, which need more remediation processes.  相似文献   

20.
Single and joint effects of pesticides and mercury on soil urease   总被引:6,自引:3,他引:3  
The influence of two pesticides including chlorimuron-ethyl and furadan and mercury (Hg) on urease activity in 4 soils (meadow burozem and phaeozem) was investigated. The soils were exposed to various concentrations of the two pesticides and Hg individually and simultaneously. Results showed that there was a close relationship between urease activity and organic matter content in soil. Chlorimuron-ethyl and furadan could both activate urease in the 4 soils. The maximum increment of urease activity by chlorimuronethyl was up to 14%-18%. There was almost an equal increase (up to 13%-21%) in the urease activity by furadan. On the contrary, Hg markedly inhibited soil urease activity. A logarithmic equation was used to describe the relationship (P〈0.05) between the concentration of Hg and the activity of soil urease in the 4 tested soils. Semi-effect dose (ED50) values by the stress of Hg based on the inhibition of soil urease in the 4 soils were 88, 5.5, 24 and 20 mg/kg, respectively, according to the calculation of the corresponding equations. The interactive effect of chlorimuron-ethyl or furadan with metal Hg on soil urease was mainly synergic at the highest tested concentrations.  相似文献   

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