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1.
Pesticides that contain a halogen functional group have been destructed by means of detonative combustion. The following compounds were examined: (1) atrazine—2-chloro-4-ethylamino-6-isopropylamino-1,3,5-triazine—herbicide; (2) bromophos—O,4-bromo-2,5-dichlorophenyl O,O-dimethyl phosphorothioate—insecticide; (3) chloridazon—5-amino-4-chloro-2-phenylopyridazin-3(2H)-one—herbicide; (4) linuron—3-(3,4-dichlorophenyl)-1-metoxy-1-methylurea—herbicide; (5) metoxychlor—1,1,1-trichloro-2,2-bis(4-metoxyphenyl)ethane—insecticide and acaricide; and (6) trichlorfon—dimethyl 2,2,2-trichloro-1-hydroxyethylphosphonate—insecticide. Explosive material has been produced on the basis of ammonium nitrate, which served as an oxidizer while the pesticides were used as fuels. Composition of the explosive was adjusted in such a way as to respect thermodynamic parameters. Detonative decomposition of the mixtures has been carried out in shot-holes pre-drilled in soil. Efficiency of the pesticide decomposition has been examined with gas chromatography in order to determine pesticides residues in the environment. It was found that for some, the amount of pesticides in some compounds in the analyzed samples after decomposition was below the determination threshold of the applied method.  相似文献   

2.
针对污水处理生化出水高磷酸盐浓度对水体富营养化影响的问题,采用阴离子交换树脂(AER)为基质材料,利用树脂上—NH2官能团中的N原子与Fe3+发生配位聚合,制备了除磷聚合配位交换吸附剂(Fe—PLE)。并采用Langmuir和Freundlich等温吸附方程对Fe—PLE和原AER进行了比较,发现Fe—PLE更加趋向化学吸附类型,且Fe—PLE最大吸附容量达到93.05 mg/g,比AER提高了47.98%。通过SEM、EDS、FT-IR及TGA对吸附前后Fe—PLE和AER的表征比较,认为通过配位作用形成Fe—O配位键是Fe—PLE的可溶性无机磷吸附效率提高的主要原因。通过静态吸附实验考察了吸附时间、pH和竞争性阴离子对AER和Fe—PLE吸附的影响,结果显示,Fe—PLE吸附平衡时间为1.5 h,比AER稍高;2种吸附填料都在pH 7.0时效率最高,AER的磷吸附效率对pH较为敏感,Fe—PLE能够在相对较宽的pH范围内保持高去除率;竞争性阴离子对AER磷吸附的负面影响较大,而Fe—PLE依靠其Fe—O的配位作用具有一定的抗干扰能力。通过4次循环再生实验,Fe—PLE表现出良好再生能力的同时磷有较高的回收利用率。  相似文献   

3.
克劳氏芽孢杆菌(Bacillus clausii S-4)吸附Zn2+的研究   总被引:2,自引:0,他引:2  
为了验证生物吸附剂去除废水中重金属离子Zn2+的可行性,筛选了一株高效吸附Zn2+的微生物菌株克劳氏芽孢杆菌Bacillus clausii S-4。采用火焰原子吸收、红外光谱和扫描电镜能谱分析,对这种新型生物吸附剂在水相中吸附Zn2+的性能和机理进行了研究。结果表明,B. clausii S-4菌体在20 ℃、30 ℃、40 ℃条件下,吸附Zn2+的最佳pH为4.5,吸附容量为57.5 mg/g,吸附容量随温度的升高而增加,吸附过程是吸热反应,吸附平衡时间约30 min。吸附前后,B. clausii S-4菌体表面上的化学官能团和金属离子发生了明显的变化,—OH、—NH+4、—COOH、(—CO—NH—)、—C6H5等官能团可能参与了吸附过程。0.1 mol/L HNO3、HCl和EDTA对锌的解吸附效果较好。在矿山废水中,B. clausii S-4菌体对Zn2+的吸附效果也比较理想,显示出其潜在的应用价值。  相似文献   

4.
An equation derived for initial collection of efficiency E0 of a gravel bed filter predicts that — ln(1 — E0) is proportional to the thickness of the gravel layer, to the — 5/3 power of the diameter of uniform gravels, and to the — 2/3 power of the Darcy airflow velocity. The experimental data obtained from NH4CI fume removal from dry air at room temperature by sieved gravel fractions generally supported the equation, except that the effect of mean gravel size was represented by the —1.43 power of the average diameter.  相似文献   

5.
以调质高炉渣为原料在实验室进行了四辊离心法制备矿渣棉实验.研究高炉渣滴落温度、粘度、离心辊径及转速等工艺参数对矿渣棉成纤效果的影响规律.结果表明,高炉渣滴落温度应控制在1 290~1 420℃之间,高炉渣粘度在1~3 Pa.s;四辊直径分别为1# 213 mm、2# 295 mm、3# 295 mm和4# 295 mm时,转速控制在1# 2 707~3 000 r/min、2# 3 093~4 000 r/min、3# 4 350~4 500 r/min和4# 5 000~5 800 r/min,成纤率较高,成纤效果良好.  相似文献   

6.
In the near future the State of Minnesota will adopt noise pollution standards and regulations based on the findings presented in this paper. Comprehensive noise standards are presented for all sources of noise, including airports, highways, and industrial sources. Two of the three dimensions of noise—intensity and frequency—are measured by the use of the unit dBA, whereas the third dimension—duration—is measured by use of the temporal distribution, expressed as Lx, where x is the sound pressure level in dBA exceeded x% of the time. Standards are established for five zones: 1. residential—single family, 2. residential— apartments, public buildings, 3. commercial, 4. manufacturing, and 5 industrial. The Lx standards apply to most noises including industrial and highway noises. Aircraft noise and impulse noise standards are also discussed. The six phase implementation plan for noise abatement is discussed.  相似文献   

7.
使用动态过滤法对聚偏氟乙烯(PVDF)超滤膜进行改性,得到PVDF/聚乙烯醇(PVA)改性膜。系统考察了改性前后PVDF超滤膜表面的微观结构变化,使用原子力显微镜结合自制的—COOH、—OH官能团探针,定量测定了改性前后超滤膜与官能团之间的作用力变化特点,并进行了富含—OH、—COOH官能团的典型有机物海藻酸钠(SA)及腐殖酸(HA)的膜污染实验。结果表明,与PVDF基膜相比,PVDF/PVA改性膜表面粗糙度增大,接触角有效降低;—COOH、—OH官能团与PVDF/PVA改性膜之间的作用力远远小于—COOH、—OH官能团与PVDF之间的作用力。在相同的膜污染运行时间内,改性膜的通量衰减速率及衰减幅度皆小于相应PVDF膜的通量衰减速率及衰减幅度。说明改性膜有效降低了膜-污染物之间相互作用力,提高了膜的抗污染能力,微观作用力评价方法可利用于揭示膜污染本质。  相似文献   

8.
针对江苏某合成氨工业氨氮废水水质特点,建立5 m3/d缺氧-曝气生物流化床中试系统.在进水氨氮浓度为13~170 mg/L、温度为8~32℃的条件下,中试系统出水氨氮去除率维持在65%~100%之间,平均氨氮去除率85%,亚硝酸盐积累率维持在40%~82%,系统出水氨氮指标达到《合成氨工业水污染物排放标准》(GB 13458-2013)中的直接排放标准.  相似文献   

9.
Ambio - Offsetting—trading losses in one place for commensurate gains in another—is a tool used to mitigate environmental impacts of development. Biodiversity and carbon are the most...  相似文献   

10.
Environmental Science and Pollution Research - The aim of this study is to assess—for the first time—the concentration of the 16 polycyclic aromatic hydrocarbons (PAHs) in the muscle...  相似文献   

11.
采用液相沉积法制备了铁氧化物/活性炭复合材料(Fe2O3@AC),通过单因素实验和正交实验优化了材料的制备条件,使用SEM、FTIR、XRD、XPS等分析方法对材料的形貌和性质进行了表征分析,通过吸附实验探究了Fe2O3@AC吸附除锑的效果及影响因素,并进一步对吸附除锑的机理进行了深入探讨。结果表明:最佳制备条件为纯水:乙醇:=4:1,Fe2+:Fe3+=1:1,总铁浓度为0.594 mol·L−1,制备液pH=1.88。Fe2O3@AC吸附除锑的能力较其他金属基材料和活性炭有明显提高,锑原水质量浓度为38 μg·L−1,Fe2O3@AC投加量为0.08 g·L−1,吸附平衡后水中锑的去除率达97%,剩余锑质量浓度为1.06 μg·L−1,满足国家饮用水卫生标准要求。微观表征显示铁氧化物颗粒成功负载于活性炭上,且铁氧化物晶体的结构完好。吸附反应符合准二级动力学和Langmuir等温模型,吸附反应以单层化学吸附为主,吸附类型为液膜扩散,颗粒内扩散,质量扩散的叠加形式。吸附方式为共沉淀,及溶解态锑与固相铁氧化物形成络合物,参与反应的官能团为—OH、—COOH、—Fe—OH、—Fe—O—Fe。  相似文献   

12.
The emission of formaldehyde is an important factor in the evaluation of the environmental and health effects of wood-based board materials. This article gives a comparison between commonly used European test methods: chamber method [EN 717-1, 2004. Wood-based panels—determination of formaldehyde release—Part 1: formaldehyde emission by the chamber method. European Standard, October 2004], gas analysis method [EN 717-2, 1994. Wood-based panels—determination of formaldehyde release—Part 2: formaldehyde release by the gas analysis method, European Standard, November 1994], flask method [EN 717-3, 1996. Wood-based panels—determination of formaldehyde release—Part 3: formaldehyde release by the flask method, European Standard, March 1996], perforator method [EN 120, 1993. Wood based panels—determination of formaldehyde content—extraction method called perforator method, European Standard, September 1993], Japanese test methods: desiccator methods [JIS A 1460, 2001. Building boards. Determination of formaldehyde emission—desiccator method, Japanese Industrial Standard, March 2001 and JAS MAFF 233, 2001] and small chamber method [JIS A 1901, 2003. Determination of the emission of volatile organic compounds and aldehydes for building products—small chamber method, Japanese Industrial Standard, January 2003], for solid wood, particleboard, plywood and medium density fiberboard.The variations between the results from different methods can partly be explained by differences in test conditions. Factors like edge sealing, conditioning of the sample before the test and test temperature have a large effect on the final emission result. The Japanese limit for F **** of 0.3 mg l−1 (in desiccator) for particleboards was found to be equivalent to 0.04 mg m−3 in the European chamber test and 2.8 mg per 100 g in the perforator test. The variations in inter-laboratory tests are much larger than in intra-laboratory tests; the coefficient of variation is 16% and 6.0% for the chamber method, 25% and 3.5% for the gas analysis method and 15% and 5.2% for the desiccator method.  相似文献   

13.
不同粒级土壤磁化率与重金属污染特征的相关关系   总被引:1,自引:0,他引:1  
采集辽宁省葫芦岛锌厂周边农田耕作层土壤,将其分为>500 μm、100~500 μm、50~100 μm、2~50 μm、χlf)和高频磁化率(χhf),用BCR连续提取法对5个粒级及未分级土样中的Pb和Cd赋存形态进行分析,并计算各粒级土壤污染负荷指数(PLI)和频率磁化率(χfd)等参数,以此探讨不同粒级土壤磁性与Pb和Cd含量、形态及PLI的关系.结果表明,粒径 χfd均增加;各个粒级土壤中Pb的可还原态(F2)含量高于其他形态,而Cd的弱酸可溶态(F1)含量高于其他形态;未分级土壤中Pb含量、Cd含量和PLI与χlf和χfd具有显著相关性,且均在0.05水平及以上;各个粒级土壤中Pb和Cd的F2含量与χlf、χfd和PLI基本达0.01水平显著相关,其显著性均高于其他形态含量与χlf、 χfd和PLI的显著性.  相似文献   

14.
为实现建筑垃圾和碱渣二次资源的综合利用,考察利用建筑垃圾和碱渣为主要原料制备蒸压加气混凝土的可行性。通过测试蒸压加气混凝土的干密度和抗压强度,确定适宜的原料配比和蒸压养护条件,并通过XRD、SEM和FTIR对蒸压加气混凝土样品的矿物组成、微观结构进行分析。结果表明,在建筑垃圾、碱渣、石灰、水泥、石膏、铝粉掺量分别为50%、20%、10%、18%、2%和0.1%、蒸压压力1.5 MPa、蒸压时间6 h的条件下,制备的蒸压加气混凝土性能达到《蒸压加气混凝土砌块》(GB 11968-2006)A7.5、B07级要求,且蒸压加气混凝土样品的主要物相为托贝莫来石、半结晶CSH(I)和少量方解石、石英和硬石膏,托贝莫来石、硬石膏和水化硅酸钙凝胶相互交错形成多孔结构,部分Si—O—Si和Al—O—Al断裂,[AlO4]取代了归属于[SiO4]中的Si—O—Si。碱渣的添加有助于激发建筑垃圾的活性,生成强度更高的含铝托贝莫来石,形成低密度高强度的蒸压加气混凝土。  相似文献   

15.
粉煤灰深度处理低浓度的磷   总被引:1,自引:0,他引:1  
为了探讨低浓度磷吸附的方法,比较了粉煤灰、煤质活性炭和粉煤灰碎砖块颗粒这3种价廉易得的吸附材料的除磷效果。经对比确定以粉煤灰为吸附剂,研究了反应时间、粉煤灰投加量以及溶液pH对深度除磷效果的影响。同时为了解粉煤灰高效除磷原理,利用SEM和XRD对其表面形状、所含元素及其内部结构进行了表征。结果表明,粉煤灰比煤质活性碳和粉煤灰砖砖块颗粒的除磷效果更好,去除率高达98.9%;SEM和XRD表征结果显示,由于粉煤灰表面积较大、表面能高、含有Si—O—Si和Si—O—Al—O偶极键及铝、铁和钙的氧化物,使得粉煤灰对低浓度的磷有着高效的去除率;吸附磷后的粉煤灰表面形成了一层絮状物,经EDS分析显示其组成以钙磷沉淀为主;1 g粉煤灰对1 mg/L的磷酸盐溶液在pH=10、反应时间60 min时表现出最佳吸附性能。  相似文献   

16.
为了明确焦化废水中总氮的构成及在生物工艺中的转化利用,统计分析了总氮及5种无机含氮化合物在A/O1/O2、A/O1/H/O2和O1/H/O2 3个生物处理工艺中的浓度变化,结合模拟实验研究好氧反应中含氮化合物的氨化作用,并探索高浓度氨氮情况下硝化作用的条件控制。结果表明,总氮由氨氮、硫氰化物、氰化物和有机含氮化合物等构成;氨氮和硫氰化物占总氮比例超过80%,是主要贡献者。模拟实验中在COD和SCN-浓度为4 465和1 238 mg/L水质状况下,控制温度17~19℃、pH 7~7.5、溶解氧 1~5 mg/L、SV30为30%,连续曝气50.5 h时实现COD和SCN-去除率达90%和99%。在O1/H/O2工艺二级好氧池中,氨氮浓度380~400 mg/L时,控制温度23~27℃、pH为7.8~8.3条件下,调试运行23 d实现完全硝化作用。研究证明,影响氨化过程与硝化过程效率的因素包括水质、温度、pH、污泥浓度与停留时间等。  相似文献   

17.
The current situation and possible future developments for nuclear power—including fission and fusion processes—is presented. The fission nuclear power continues to be an essential part of the low-carbon electricity generation in the world for decades to come. There are breakthrough possibilities in the development of new generation nuclear reactors where the life-time of the nuclear waste can be reduced to some hundreds of years instead of the present time-scales of hundred thousand of years. Research on the fourth generation reactors is needed for the realisation of this development. For the fast nuclear reactors, a substantial research and development effort is required in many fields—from material sciences to safety demonstration—to attain the envisaged goals. Fusion provides a long-term vision for an efficient energy production. The fusion option for a nuclear reactor for efficient production of electricity has been set out in a focussed European programme including the international project of ITER after which a fusion electricity DEMO reactor is envisaged.  相似文献   

18.
滇池流域某分流制小区雨水径流水质及初期冲刷规律研究   总被引:1,自引:0,他引:1  
为研究滇池流域呈贡地区典型城市小区的雨水径流水质规律及其初期冲刷效应,以便为揭示滇池污染原因和水环境治理积累基础资料,研究选取洛龙河公园旁边一典型分流制城市小区为对象,在雨水排放口布置监测点进行雨水水质水量监测.结果表明,雨水径流污染较为严重,各场次TSS、COD的EMC值都超过了《城镇污水处理厂污染物排放标准》(GB 18918-2002)的一级B标准.初期冲刷效应普遍存在,且随着雨强的增大而增强,截留降雨前期50%的雨水径流量,能有效截留TSS、COD、TN、TP、NH3-N的比例分别为56.1%~68.3%、55.1%~64.0%、54.9%~61.4%、44.4%~57.7%和54.7%~58.0%.滇池流域呈贡地区城市小区在雨水径流量累积达到0.6之前,截留效率随着截留径流量的比例增加而增加,控制截留的径流量体积比例在0.4~0.8能够取得较高的污染物截留效率.  相似文献   

19.
The Emergency Planning and Community Right-to-Know law is an exciting new approach to environmental protection. It is based on the belief that the more information citizens have about environmental conditions in their communities, the better equipped they will be to insure their own protection from unacceptable risks to their health and safety. The law requires disclosure by industry of both the presence and release into the environment—including both accidental and “routine” releases—of hazardous substances. The information will be available not only to government regulators, but also to the people most directly affected—the residents of the communities where the substances are located.  相似文献   

20.
人工快速渗滤系统(CRI)非饱水层主要完成COD的降解和氨氮的转化,是影响整个系统出水效果的关键部分.通过实验,研究了CRI非饱水层对生活污水中COD和氨氮的去除效果,并分别就pH对其影响机理进行了探讨.结果表明,污水经过CRI非饱水层后,COD的平均浓度由220.66 mg/L降至19.36~25.59 mg/L,去除率为88.13%~90.90%;氨氮平均浓度由58.13 mg/L降至18.81~28.73 mg/L,去除率为49.40%~64.09%,前者去除效果基本不受pH影响,后者受pH影响较大.  相似文献   

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