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91.
城市污泥及其堆肥施用对通菜中有机污染物的累积效应   总被引:19,自引:1,他引:19  
Mo C  Cai Q  Wu Q  Wang B  Li G  Zhu X 《环境科学》2002,23(5):52-56
在水稻土上施用城市污泥及其堆肥盆栽通菜,应用GC/MS联机检测技术对植株中8类共44种有机污染物进行系统分析。结果表明,通菜中检出28种有机化合物,主要是邻苯二甲酸酯类、硝基苯类和多环芳烃类化合物。各类污染物均以个别或少数化合物为主,其它化合物的含量低得多或未检出。施用污泥的通菜中有机污染物的含量普遍较高,是空白对照的数倍至数10倍,而施用各种污泥堆肥的通菜中有机污染物的含量普遍较低,甚至低于空白对照,尤其是施用污泥加牛粪堆肥的通菜中仅检出1种化合物。因此,污泥直接施用可能导致作物中有机污染物的吸收累积,需经适当的堆肥处理后施用才较为安全。  相似文献   
92.
北京大气气溶胶中有机碳及可萃取有机卤素污染物   总被引:5,自引:0,他引:5       下载免费PDF全文
研究了2002年5月~2003年4月北京城区大气中PM2.5和PM10中有机碳(OC)及可萃取有机卤素污染物(EOX)的浓度.结果表明,PM10和PM2.5的年均值分别为172.8μg/m3和110.9μg/m3,分别是美国年均值标准(PM10, 50μg/m3; PM2.5, 15μg/m3)的3.5倍和7.4倍,说明污染相当严重;PM2.5与PM10中OC的月均浓度分别为9.1~33.9μg/m3和13.1~46.2μg/m3,冬季大气中OC的浓度最高,夏季最低; PM2.5中OC和EOX的百分含量高于PM10,细粒子更易于富集有机污染物; PM2.5和PM10中EOX的含量顺序为EOCl>> EOBr(EOI),约有73%~88%和69%~91%的EOX为EOCl,大气中的有机卤素污染物主要为有机氯污染物;PM2.5中OC与EOX的含量变化趋势一致,细颗粒物中OC对EOX的含量起到了控制作用,PM10中OC对EOX的含量影响有限.  相似文献   
93.
用土壤薄层层析法研究单甲脒,单甲脒盐酸盐、灭幼脲和涕灭威等农药在不同土壤中的迁移行为,分别获得了这几种化合物的Rf值,它们分别为0.14、0.17,0.08,0.76,研究表明,单脒,单甲脒盐酸盐和灭幼脲不会污染地下水,而涕灭威则会对地下水污染构成严重的威胁。  相似文献   
94.
Whole effluent toxicity was assessed for the fish Oryzias latipes and the prawn Macrobrachium nipponense for 18 h in a dilution series (0-66%) of the inflow and effluent of a municipal waste water treatment plant as well as waste water from a teramycin producing pharmaceutical industry, before, during and after a pilot laboratory purification process. The waste waters caused acute toxicity as measured by inhibition of light emission in the luminiscent bacterium Vibrio qingaiensis sp. nov. (Q67). EROD and aryl hydrocarbon hydroxylase activity in in vitro carp liver-cells showed a dose-dependent toxic response to the municipal waste water. Behavioural responses and time-to-death of fish and prawn, recorded online with the "Multispecies Freshwater Biomonitor" proved to be concentration- and time-dependent sensitive toxicity indicators in both types of waste water. Behaviour changed stepwise from normal activity to (increased or decreased) activity to more time spent on ventilation and finally to increased morbidity at higher concentration and time of exposure. The municipal waste water treatment plant managed to reduce toxicity to bacteria (Q67), prawn and fish. The pharmaceutical waste water treatment process still has to be improved, in order to reduce toxicity for fish and prawn.  相似文献   
95.
DDT污染土壤的植物修复技术   总被引:2,自引:0,他引:2  
本文报道用植草方法研究为DDT及其主要降解产物污染土壤的植物修复技术。在污染物的浓度为 0 .2 15mg/kg的土壤中 ,种植 10种草 3个月后DDT及其主要降解产物的总含量分别降低 19.6 %— 73.0 %。种植不同品种的草对土壤中污染物有不同的去除能力 ,其中以种植丹麦产的Taya草 (Per .ryegrass)与美国产的Titan草 (Tallfescue)为最强。用种植草的方法修复受DDT及其主要降解产物污染的土壤是一项可行的技术。在去除土壤中DDT的作用上 ,草的吸收是轻微的 ,只占原施药量的 0 .13%— 1.0 8% ,土壤中污染物消失的主要因素是土壤中生物降解作用的结果。  相似文献   
96.
During continuous operation of three mesophilic-anaerobic digesters, the effect of microwave irradiation, as sludge thermal pretreatment (60 to 65 degrees C), was studied. The fecal coliforms log inactivation for microwaved/digested sludge was 4.2 +/- 0.4, whereas for conventionally heated/digested sludge and control were 2.9 +/- 0.5 and 1.5 +/- 0.5, respectively. In the case of Salmonella spp., no colonies were detected in 85% of the microwaved/digested samples. Considering the detection limit, the log inactivation of these samples was greater than 2.0 +/- 0.3. The conventionally heated/digested sludge and control showed log inactivations of 1.9 +/- 0.2 and 1.1 +/- 0.3, respectively. At the 95% confidence level, microwaved/digested sludge increased the biogas production by 16.4 +/- 5.6% and 6.3 +/- 2.4%, as compared to control and conventionally heated/digested sludge, respectively. When thermally treated sludge was analyzed for soluble chemical oxygen demand, microwaved waste-activated sludge showed considerable solubilization between 37 and 60 degrees C. Microwaved/digested sludge showed a reduction of capillary suction times by 11.1 +/- 5.9% and 10.7 +/- 5.6%, as compared to control and conventionally heated/digested sludge, respectively.  相似文献   
97.
单甲脒在土壤中的吸附   总被引:20,自引:2,他引:20  
杨克武  安凤春 《环境化学》1995,14(5):431-435
用批量平衡法研究了单四脒酸盐的活性部分-单甲脒在不同类型土壤中的吸附行为,获得了单甲脒的单位土壤有机质吸附常数(Kom)为284和吸附自由能变化量为13.99kJ.mol^-1的实验数值,研究表明,单甲脒在土壤中吸附符合Freundlich经验公式,其在土壤中的吸附系数Kd与土壤中有机质含量和阳离了交换容量均显著正相关。  相似文献   
98.
作为一种性质优异的吸附材料,石墨烯类材料对有机物和重金属等多种水污染物均有出色的吸附能力,因此其在水处理和地下水修复工作中的应用前景在近几年备受关注.当前的研究总体上尚停留在实验室模拟阶段,在提高材料饱和吸附量的同时,研制出低成本、稳定性强、易于再生利用且环境友好的石墨烯类材料是今后的发展趋势.本文对石墨烯类材料的种类及制备方法进行了归纳总结,对他们在水处理和地下水修复中的应用研究情况进行了综述,对当前研究中存在的问题进行了分析,最后对未来的研究和应用前景进行了总结和展望.  相似文献   
99.
A single particle aerosol mass spectrometer was deployed to measure the changes of single particle species and sizes during March 2015 in Weizhou Island of the Beibu Gulf, Guangxi province, South China. In this campaign, a total of 3,100,597 particles were sized, and 25.8%particles with both positive and negative mass spectrum were collected and 24.8%characterized in combination with the ART-2 a neural network algorithm. The distribution of sized particles was mainly in from 520 to 600 nm, and the diameters ranging from 340 to1000 nm accounted for above 90%. Eight types of particles were classified: Elemental Carbon containing(EC), Organic Carbon containing(OC), EC and OC combined containing particles,Na containing particles, K containing particles(K), Levoglucosan containing particles,mineral containing particles, and Heavy Metal containing particles(HM). EC, OC and K were the major containing particles, which accounted for 84.3% in the eight types particles. The relative ratio and size distribution of the three types were EC(48.1%, 620 nm), OC(12.7%,440 nm), and K(23.5%, 600 nm), respectively. The three types of particles were a bit increasing ratios compared with those in clean periods during haze pollution periods.Combined with the back-trajectory results from the Hysplit-4 model and local pollution sources revealed that the ambient air quality on the Weizhou Island may be influenced by biomass burning in the Indochina Peninsula(biomass burning in the Indochina Peninsula)from the transportation on higher level atmospheric layer and by mainland of south China located northeast of Weizhou Island on the ground.  相似文献   
100.
PM_(2.5) aerosol samples were collected over 12 hr and 24 hr intervals in an inland background area, Gongga Mountain National Nature Reserve(hereafter shortened to Gongga), during the summer of 2011. Polar organic tracers, inorganic ions and meteorological data were measured. The purpose of this work was to investigate the variation patterns, formation and sources of the secondary organic aerosol tracers in the studied atmosphere. The average concentrations of isoprene oxidation products, α-pinene oxidation products, β-caryophyllinic acid, sugars, sugar alcohols and anhydrosugars were 88.6 ± 106.1, 3.6 ± 5.7,0.13 ± 0.30, 13.6 ± 13.1, 31.9 ± 31.4 and 14.8 ± 10.7 ng/m3 respectively in all aerosol samples.The aged α-pinene second organic aerosol(SOA) tracers(i.e., 3-hydroxyglutraric acid(3 HGA), 3-hydroxy-2,2-dimethylglutaric acid(HDMGA), 3-acetylpentandioic acid(APDA) and 3-methyl-1,2,3-butanetricarboxylic acid(MBTCA)) correlated significantly with each other in the 24 hr PM2.5 aerosol samples, indicating that OH· is the major factor controlling the formation of these α-pinene SOA tracers. Using the positive matrix factorization(PMF) model and the tracer-based source apportionment method, we calculated that isoprene oxidation products, α-pinene oxidation products, sesquiterpene oxidation products, biomass burning, fungi spores and anthropogenic SOA accounted for 21.9% ± 5.5%, 8.4% ± 2.1%, 3.0% ± 0.7%, 5.2% ± 5.3%, 5.0% ± 6.2% and 31.4% ± 7.8% of organic carbon respectively during the sampling period.  相似文献   
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