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1.
空气冷凝水的测定及意义   总被引:4,自引:1,他引:4  
为了进一步探索酸雨形成问题,提出了“空气冷凝水”,即用人工降温的方法使空气中的水汽冷凝成水样,并收集作为成分分析的样品。用该方法对本地空气凝水的pH值、电导率、进行了测定,共获有效数据239个。并与降水进行了比较,对本地酸雨成因作了简单分析,阐述了“空气冷凝水”在酸雨研究中的意义,提出了本人对酸雨研究工作的一些看法。  相似文献   

2.
什么是“绿色GNP”绿色GNP是指在国民生产总值(GNP)中扣除对人为活动而被破坏的环境进行恢复、治理所需的费用后,剩余的国民生产总值。在绿色ONP的概念中,除去像空气这样取之不尽、用之不竭的环境资源可以无偿使用外,其他环境资源均应为有价物资,任何企...  相似文献   

3.
孙钰 《环境保护》2012,(7):35-36
在2012年“两会”上,全国政协人口资源环境委员会副主任王玉庆于3月10日在全国政协十一届五次会议上做了“尽早制定实施国家清洁空气行动计划”的大会发言.“两会”期间,《环境保护》杂志记者就制定实施清洁空气行动计划的相关问题对王玉庆副主任进行了专访.新型大气污染已成突出环境问题 《环境保护》:近年来,我国大气污染特征发生了很大的变化,请介绍新型大气污染对人体造成了哪些危害?  相似文献   

4.
目前,随着泡沫塑料的应用和丢弃,产生的“白色污染”已遍布全国各地。国家有关部门和企业已对其进行了回收再生及利用途径的攻关和研究。为保护环境,使废物资源化,达到资源的永续利用,本对泡沫塑料的回收再生和利用途径进行了探讨,以求资源的合理利用和减轻对环境的污染。  相似文献   

5.
区域空气资源的评估方法及其在台湾海峡西岸地区的应用   总被引:3,自引:2,他引:1  
从区域大气环境管理的需要出发,提出了空气资源的概念、等级计算及评估方法.以台湾海峡西岸(简称"海西")地区为例,在深入分析该地区污染气候特征和各种特殊污染气象过程特点、频率及对空气资源的制约因素基础上,利用新一代气象模式WRF进行了区域尺度和局地尺度的气象场模拟.从模拟的气象要素场及湍流特征量中筛选出影响空气资源的主要...  相似文献   

6.
废旧锌锰电池回收处理工艺的探讨   总被引:2,自引:0,他引:2  
由于电池耗费量日益增加,废旧电池导致的环境污染问题倍受关注。通过对废旧电池的调研和处理技术的对比研究,提出了“焙烧—电解”回收处理废旧锌锰电池的工艺技术。在600℃、隔绝空气焙烧3h的试验条件下,“焙烧—电解”工艺不仅可回收大量的二氧化锰、锌、氯化锌、炭棒、铜帽、铁皮、蜡等资源,而且废气、废水、废渣经处理后完全达标排放。阐述了具体的“焙烧—电解”工艺。  相似文献   

7.
空气资源评估方法及其在城市环境总体规划中的应用   总被引:6,自引:1,他引:5  
从空气污染气候学的角度,提出了空气资源禀赋的概念、评估方法、等级划分及分区管控的理念.同时,以宜昌城市环境总体规划为例,利用MM5耦合CALMET模式对大气环境系统进行解析,计算了宜昌市域范围高时空分辨率(1 km×1 km)通风系数A值分布,并作为空气资源禀赋等级分区的依据.在此基础上,将空气资源分区的结果与地理信息系统相结合,给出其空间分布,强化了分区管控政策的空间落地.评估结果表明,宜昌地区空气资源禀赋等级共分为4级,A值在8以上的空气资源禀赋充裕的地区,约占市域面积的30.3%;较好和一般的地区,A值分别在5~8和3~5之间,约占34.1%和34.8%;A值在1~3之间空气资源禀赋稀少的地区,仅占0.8%.本研究提出的空气资源禀赋分区方法具有较强的合理性,预期在城市中长期发展过程中的产业布局与分级调控中具有较好的应用前景.  相似文献   

8.
对不同的刷漆作业场所进行现场卫生学调查及空气中“三苯”浓度监测的结果表明,较小规模的手工刷漆作业场所“三本”浓度高于机械制造业喷漆作业场所。该文分析其产生原因,提出了防治措施。  相似文献   

9.
论环境效益     
“人类环境”一词包含了我们周围的一切事物,和我们与这些事物之间的关系。联合国环境规划署(UNEP)把重点放在人类如何合理地利用地球上的资源(不论是有限的资源还是可以再生的资源),这也是商业界和工业界关注的中心,因为需要保护的资源的范围已大大扩大。我们现在必须把清洁的空气、水源、优质土壤、野生植物和森林看成象煤炭、石油、  相似文献   

10.
上海地铁车站空气中CO2浓度调查   总被引:6,自引:0,他引:6  
钱华  李德 《上海环境科学》1999,18(7):306-308
1998年5月末对上海地铁人民广场站和漕宝路站2个站台内空气中CO2浓度进行了监测,以日本,美国,澳大利亚和韩国4个国家的室内空气质量标准进行影响评价。结果表明:2个地铁站内空气中CO2浓度在大部分运营时间内低于1571.4或1178.8mg/m^3,属“可”或“良”。  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.
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   

14.
RemovalofheavymetalsfromsewagesludgebylowcostingchemicalmethodandrecyclinginagricultureWuQitang,NyirandegePascasie,MoCehuiF...  相似文献   

15.
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   

16.
A study was conducted to compare the diversity of 2-, 3-, and 4-chlorobenzoate degraders in two pristine soils and one contaminated sewage sludge. These samples contained strikingly different populations of mono-chlorobenzoate degraders. Although fewer cultures were isolated in the uncontaminated soils than contaminated one, the ability of microbial populations to mineralize chlorobenzoate was widespread. The 3- and 4-chlorobenzoate degraders were more diverse than the 2-chlorobenzoate degraders. One of the strains isolated from the sewage sludge was obtained. Based on its phenotype, chemotaxonomic properties and 16S rRNA gene, the organism S-7 was classified as Rhodococcus erythropolis. The strain can grow at temperature from 4 to 37℃. It can utilize several (halo)aromatic compounds. Moreover, strain S-7 can grow and use 3-chlorobenzoate as sole carbon source in a temperatures range of 10-30℃ with stoichiometric release of chloride ions. The psychrotolerant ability was significant for bioremediation in low temperature regions. Catechol and chlorocatechol 1,2-dioxygenase activities were present in cell free extracts of the strain, but no (chloro)catechol 2,3- dioxygenase activities was detected. Spectral conversion assays with extracts from R. erythropolis S-7 showed accumulation of a compound with a similar UV spectrum as chloro-cis,cis-muconate from 3-chlorobenzoate. On the basis of these results, we proposed that S-7 degraded 3-chlorobenzoate through the modified ortho-cleave pathway.  相似文献   

17.
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   

18.
The contribution of aliphatic-rich plant biopolymer to sorption of hydrophobic organic compounds is significantly important because of their preservation and accumulation in the soil environment,but sorption mechanism is still not fully understood.In this study, sorption of 1-naphthol by plant cuticular fractions was examined to better understand the contributions of respective fraction.Toward this end,cuticular materials were isolated from the fruits of tomato by chemical method.The tomato cuticle sheet consisted of waxes (6.5 wt%),cuticular monomer (69.5 wt%),and polysaccharide (24.0 wt%).Isotherms of l-naphthol to the cuticular fractions were nonlinear (N value (0.82-0.90)) at the whole tested concentration ranges.The KodKow ratios for bulk cuticle (TC1),dewaxed cuticle (TC2),cutin (TC4),and desugared cuticle (TC5) were larger than unity,suggested that tomato bulk cuticle and cutin are much powerful solption medium.Sorption capability of cutin (TC4) was 2.4 times higher than the nonsaponifiable fraction (TC3).The 1-naphthol interactions with tomato cuticular materials were governed by both hydrophobic-type interactions and polar (H-bonding) interactions. Removal of the wax and polysaccharide materials from the bulk tomato cuticle caused a significant increase in the sorption ability of the cuticular material.There was a linear negative trend between K_(oc) values and the amount of polysaccharides or fraction's polarities ((N O)/C);while a linear positive relationship between K_(oc) values and the content of cutin monomer (linear R~2=0.993) was observed for present in the cuticular fractions.Predominant sorbent of the hydrophobic organic compounds (HOCs) in the plant cuticular fraction was the cutin monomer,contributing to 91.7% of the total sorption of tomato bulk cuticle.  相似文献   

19.
Common silver barb,Puntius gonionotus,exposed to the nominal concentration of 0.06 mg/L Cd for 60 d,were assessed for histopathological alterations(gills,liver and kidney),metal accumulation,and metallothionein(MT)mRNA expression.Fish exhibited pathological symptoms such as hypertrophy and hyperplasia of primary and secondary gill lamellae,vacuolization in hepatocytes,and prominent tubular and glomerular damage in the kidney.In addition,kidney accumulated the highest content of cadmium,more than gills and liver.Expression of MT mRNA was increased in both liver and kidney of treated fish.Hepatic MT levels remained high after fish were removed to Cd-free water.In contrast,MT expression in kidney was peaked after 28 d of treatment and drastically dropped when fish were removed to Cd-free water.The high concentrations of Cd in hepatic tissues indicated an accumulation site or permanent damage on this tissue.  相似文献   

20.
Seed induces and promotes the crystallization of calcium phosphate, and acts as carrier of the recovered phosphorus (P). In order to select suitable seed for P recovery from wastewater, three seeds including Apatite (AP), Juraperle (JP) and phosphate-modified Juraperle (M-JP) were tested and compared. Batch and fixed-bed column experiments of seeded crystallization of calcium phosphate were undertaken by using synthetic wastewater with 10 mg/L P phosphate. It shows that AP has bad enduring property in the crystallization process, while JP has better performance for multiple uses, and M-JP is a hopeful seed for P recovery by crystallization of calcium phosphate.  相似文献   

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