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121.
以嘉陵江沉积物为菌源,利用荧光绝对定量(qPCR)技术探究了不同碳源(葡萄糖和乙酸钠)和不同形态的锰氧化物(δ-MnO2和锰矿粉)对异化Mn(IV)还原菌激活效果的影响.在此基础上,研究了激活效果最佳的异化Mn(IV)还原菌对卡马西平、布洛芬、萘普生、雌激素和双氯芬酸5种有机药物的去除效果.结果表明,葡萄糖作为碳源,δ-MnO2作为电子受体时激活效果最佳,Mn2+10d累计生成浓度达416.03mg/L,TOC消耗率达88.24%.激活后的异化金属还原菌在有无外加碳源时对卡马西平和布洛芬均无明显去除,对萘普生在外加碳源时能实现11.88%的去除.雌二醇和双氯芬酸可以作为异化Mn(IV)还原菌唯一碳源,其去除率可达75.70%和58.25%. 相似文献
122.
A specific enzootic form of geophagia (the deliberate ingestion of soil) occurs in young cattle and sheep in restricted areas of the Barkley-West, Postmasburg and Vryburg Districts of the Northern Cape- and North West Provinces of the Republic of South Africa. It results in severe, subacute to chronic hepatitis and jaundice, with a high mortality rate in untreated cases. An association between the disease and high concentrations of manganese in soils was shown since all the affected farms are situated on outcrops of the Reivilo Formation of the Campbell Rand Subgroup, which consists mainly of manganiferous dolomite. Furthermore high concentrations of manganese were found in the analysis of liver specimens from affected calves and the characteristic microscopic pathological changes in the liver could be induced experimentally in a calf and lamb by oral administration of manganese sulphate. The highest incidence of geophagia occurs at 7 to 14 days, whereas calves older than about 2 months are rarely affected. The symptoms usually start with intermittent, progressive geophagia, followed by constipation, dehydration and death within ca. 7–10 days in untreated cases. Young calves and lambs display an insatiable appetite for soil and sometimes lick iron poles. The treatment of calves by the parenteral injection of commercial iron-dextran- and vitamin B12 preparations at 1 to 2 days after birth, and at 14 days of age, at the registered therapeutic doses, appeared to have a marked preventative effect on the occurrence of geophagia and its complications. Regional geochemical maps show a northeast–southwest trending anomaly in MnO, Zn and Pb, visually correlating with the distribution of the affected farms. Anomalously high distributions of Pb and Zn are also spatially related to the Pering (Pb,Zn) Mine. In this study, two farms were selected for comparative purposes. Gam, a farm situated on the Reivilo Formation of the Campbellrand Subgroup was chosen where a high incidence of geophagia occurred, as well as the farm Holpan on the Lyttelton Formation of the Malmani Subgroup where the problem was not known to be present. The farm Holpan was chosen as a control area, and is situated close to an old manganese mine on dolomite with a high MnO content. Geographically, Holpan is situated in an area with a high rainfall, with leaching and the formation of deep red soils on the dolomite, together with a hilly relief and low soil pHH
2
O. Gam is situated in an area with lower rainfall, where precipitation would be less than evapotranspiration. The dolomite of the Malmani Subgroup and the Reivilo Formation are significantly different in their soil geochemistry. The MnO, Fe2O3
T and Co contents are significantly higher in the soils of the Malmani Subgroup than in the Reivilo Formation. The MnO, Zn and Pb contents on Gam are higher than on Holpan, whereas the Fe2O3
T and Co contents are lower. Soil on Holpan contains iron-minerals such as haematite, while no iron minerals were detected in the soils of Gam. The concretions, found in the soils on both farms, differs remarkably in iron-contents. Concretions on both farms have similar high concentrations of MnO, whereas the FeO content are low for the concretions on Gam and high for Holpan. Preliminary comparative analytical results of the colostrum, sampled from cows with new born calves within three days of birth, do not entirely reflect the soil geochemistry of the different farms. Whereas the soils on Gam have higher MnO, Zn and Pb, and lower Fe2O3
T and Co than Holpan, the colostrum produced on Gam has lower Mn, Fe and Co than on Holpan. The Pb and Zn concentrations in the colostrum on both farms do not differ significantly. The comparative regional geochemical soil data, together with the colostrum data, suggest that young calves on the farm Gam probably suffer from Fe and Co deficiency. Conversely, it was illustrated that the Fe and Co content in the soils are high and the Fe is abundant in the concretions on the farm Holpan. These findings, together with the apparent absence of geophagia at Holpan, as well as the observed effect of iron and cobalt supplementation in the prevention of geophagia on the farm Gam, suggests an association of geophagia with iron and cobalt deficiencies on the farm Gam. 相似文献
123.
用含锰废水生产高纯碳酸锰 总被引:4,自引:0,他引:4
介绍了用含锰废水生产高纯碳酸锰的原理和工艺条件,生产出的高纯碳酸锰产品质量可以达到了GB10503-89Ⅱ型一等品标准,此法具有较好的经济效益和环境效益。 相似文献
124.
从废旧锌锰电池中回收锌和锰的工艺研究 总被引:3,自引:0,他引:3
废旧锌锰干电池经过剖开、焙烧处理,去除汞和碳粉,再用硫酸浸取,滤液采用沉淀法分离锌和锰。锌和锰的回收率分别为94.5%和93.6%。 相似文献
125.
阐述了水中高锰酸盐系数的概念,由化学反应机理论述了化学需氧量与高锰酸盐指数之间的关系,由1998年淮河流域安徽段全年监测数据拟合出相关函数,并对实测工作中高锰酸盐出现的异常情况进行调查研究,提出了高锰酸盐系数测定操作方法的改进意见,对实际监测工作有一定参考价值。 相似文献
126.
通过对滇池进行全湖集中采样和分析,揭示了滇池水体五日生化需氧量(BOD5)和高锰酸盐指数(CODMn)的空间变化规律.BOD5和CODMn变化范围分别是2.3~7.9mg/L,5.1~15.4mg/L,BOD5平均值草海(5.9mg/L)高于外海(5.1mg/L)CODMn平均值外海(10.17mg/L)高于草海(8.67mg/L),2个指标在入河口水域都相对较高.水平方向上,BOD5变化特点是南北高,中间低,西部高,东部低.垂直方向向上BOD5随水深增加递减.而CODMn的高值区域主要出现在草海和外海海埂、盘龙江、大青河入湖口水域、西部观音水域以及东北部宝象河、东部梁王河和捞鱼河入湖口水域、东南柴河入湖口水域.垂直方向上,从表层到水-沉积物界面水体,其CODMn都呈增加趋势.随着工业点源污染的控制,城市生活污水的排入和面源有机污染物的输入以及内源释放是决定滇池BOD5和CODMn空间变化的主要原因. 相似文献
127.
《环境科学学报(英文版)》2023,35(3):593-602
The combined pollution of heavy metals is ubiquitous worldwide. Mn/Al-layered double oxide-loaded crab shells biochar (LDO/BC) was prepared, so as to remediate the combined pollution of Cd and Cu in soil and water. The pristine and used LDO/BC were characterized and the results revealed that the layered double oxide was successfully loaded on crab shells biochar (BC) and metal element Ca in crab shells was beneficial to the formation of more regular layered and flake structure. The maximal adsorption capacity (Qm) of LDO/BC for aqueous Cu2+ and Cd2+ was 66.23 and 73.47 mg/g, respectively. LDO/BC and BC were used to remediate e-waste-contaminated soil for the first time and exhibited highly efficient performance. The extraction amount of Cu and Cd in the contaminated soil by diethylene triamine penta-acetic acid (DTPA) after treating with 5% LDO/BC was significantly reduced from 819.84 to 205.95 mg/kg (with passivation rate 74.8%) and 8.46 to 4.16 mg/kg (with passivation rate 50.8%), respectively, inferring that the bioavailability of heavy metals declined remarkably. The experimental result also suggested that after remediation by LDO/BC the exchangeable and weak acid soluble Cu and Cd in soil translated to reducible, residual and oxidizable fraction which are more stable state. Precipitation, complexation and ion exchange were proposed as the possible mechanisms for Cd and Cu removal. In general, these experiment results indicate that LDO/BC can be a potentially effective reagent for remediation of heavy metal contaminated water and soil. 相似文献
128.
129.
Güleryüz G Arslan H Kirmizi S Güçer S 《Environmental pollution (Barking, Essex : 1987)》2002,120(3):707-716
In this study, the effect of mine work wastes on elemental composition (N, P, Ca, K, Mg, Fe, Mn, Cu, Zn) of some alpine and subalpine plant species and in soils were investigated in the surroundings of the Etibank Wolfram Mine Work in Uludag mountain. Soils and plant parts belonging to Thymus praecox Opiz., Acinos alpinus (L.) Moench, Plantago holosteum Scop and Festuca punctoria Sm species collected from three directions around Wolfram Mine Work were used for our investigations. All samples were analysed by flame atomic absorption spectrophotometer (FAAS) for Ca, K, Mg, Mn, Fe, Zn, and Cu. The significant differences among sample sites were in terms of pH, % CaCO3, % C, % N and % P contents of soil. The changes of Ca, Mg, Fe, Mn, Fe, Zn, and Cu contents in soil were determined to be due to mining activity. Of the four species examined, an important change was determined in concentrations of Mg, Mn, Fe and Zn although P. holosteum and F. punctoria were different in above- and below-ground parts, showing that plant element content is specific to species. 相似文献
130.