梁子岛水污染防治对策研究

梁子岛水污染调查是梁子岛生态环境保护、生态发展规划的基础工作.以实地调查为基础,主要从梁子岛居民生活污染、农业面源污染、禽畜养殖污染,旅游污染以及水产养殖污染等方面对梁子岛进行调查,并计算出相应的COD、NH3-N、TP、TN等指标的排放量.以梁子岛水污染的实际情况为依据,提出梁子岛水污染防治的具体措施,为制定水污染治理的规划和措施提供了理论依据.     

福建省城市生活饮用水源地水质状况分析

分析了我省饮用水源地水质状况和存在的问题，提出了保护饮用水源的对策措施。     

电感耦合等离子法测定环境积尘中铅的研究

用细毛刷清扫收集普通居民房顶积尘,参照土壤样品预处理方法-普通酸分解法处理样品,以国标样品、不确定度实验、加标回收实验为质控手段,探索采用电感耦合等离子法测定环境积尘中铅的含量。实验结果表明,该法能将积尘样品完全消解,且电感耦合等离子法测试方法性能稳定、快速、准确,优于其他方法。     

北极新奥尔松地区粪土中大肠杆菌和肠球菌的分布及耐药性分析

采用滤膜法对2012年北极黄河站科学考察采集的新奥尔松地区8个鹿粪和1个鸟粪样品进行分离鉴定,共获得84株肠球菌和85株大肠杆菌。84株肠球菌分属于10个属,其中屎肠球菌（28株）、鼠肠球菌（28株）及鸟肠球菌（10株）为优势菌。采用K-B纸片法对受试菌株进行药敏试验结果显示:85株大肠杆菌对利福平全部耐药,对氨苄西林的耐药率为81%;对甲氧苄啶（TMP）、喹诺酮类的萘啶酸（NAL）与环丙沙星（CIP）、四环素（TCY）4种抗生素高度敏感。84株肠球菌中屎肠球菌对氨苄西林耐药率最高（89%）,对万古霉素耐药率最低（4%）。10株鸟肠球菌对利福平全部耐药,而28株鼠肠球菌对利福平耐药率最低（4%）,对链霉素耐药率最高（75%）。18株其他肠球菌对利福平耐药率最高（61%）。上述结果表明抗生素耐药性已出现于北极新奥尔松地区野生动物肠道菌群中。     

A comparative study of the interaction between microhole sidewall and the plasma generated by nanosecond and femtosecond laser ablation of deep microholes

High-aspect-ratio microholes have many industrial applications, but are difficult to produce. Femtosecond (fs) and nanosecond (ns) laser ablation may produce potential manufacturing solutions. However, the laser-induced plasma–microhole sidewall interaction has not been well understood for laser ablation of deep microholes, which may significantly affect the hole size and/or quality. This interaction has been investigated in this paper. Due to the huge challenges involved in direct experimental observations, a physics-based model is applied as the research tool, which has been verified by measurements from literatures on laser ablation of flat targets (without deep microholes) that are relatively easy to perform. The study shows that under the same laser pulse fluence, the fs laser-induced plasma generates larger transient peak heat flux to the sidewall than the ns laser pulse. However, the high-heat-flux region moves up very rapidly in the hole, and hence the sidewall temperature is not significantly raised and sidewall melting does not occur under the studied conditions. On the other hand, for the ns laser pulse, the induced plasma maintains a relatively high heat flux to the sidewall near the hole bottom for a much longer time, which yields obvious sidewall melting and surface vaporization. The results are consistent with the previously observed sidewall surface morphology for microholes drilled by fs and ns laser pulses in air with the same pulse energy.     

Chromosome doubling of Sedum alfredii Hance: A novel approach for improving phytoremediation efficiency

Sedum alfredii Hance is a cadmium(Cd)/zinc(Zn) hyperaccumulator native to China.However, its relatively low biomass restricted the large-scale application for heavy metal contamination remediation. The chromosome set doubling of S. alfredii in vitro was achieved by 0.1%–0.2%(W/V) colchicine treatment. The plant DNA ploidy was analyzed by flow cytometry and chromosome set doubling plants(CSD) were identified based on the obvious different sharp peak. A tissue culture experiment with different Cd treated levels and a field trial with natural polluted mined soil were conducted to study the effects of chromosome doubling on plant biomass and Cd accumulation in shoots. The results suggested that S.alfredii is a mixoploid. Compared with the wild type plants(WT), CSD exhibited typical"gigas" characteristics in morphology including stem thickness, root hair production,number of leaves and size of stoma guard cell. Fresh weight and dry weight of CSD were increased to 1.62–2.03-fold and 2.26–3.25-fold of WT. And Cd content of CSD showed a17.49%–42.82% increase and 59% increase under tissue culture and field condition,accordingly. In addition, the TF and in BCF of CSD were 2.37-and 1.59-fold of WT,respectively. These results proved that it is feasible to promote phytoextraction efficiency of S. alfredii in Cd contaminated soils through chromosomal engineering, which provides a novel approach for hyperaccumulator application in phytoremediation.     

Health risk assessment of heavy metal exposure through vegetable consumption around a phosphorus chemical plant in the Kaiyang karst area,southwestern China

The phosphorus chemical industry is an important source of heavy metals in farmland. Vegetables grown on contaminated soil potentially impose adverse effects on human health. In this study, the pollution status and health risks of heavy metals in vegetables around a phosphorus chemical plant in Kaiyang County, Guizhou Province, southwestern China, were assessed, and the low-accumulation vegetables were screened by bioaccumulation factor (BAF) and cluster analysis. Results showed the average concentrations of Hg, As, Cd, Pb, Cr, Mn, Co, and Zn in vegetables were 0.015, 0.728 0.382, 0.227, 0.850, 27.227, 0.525, and 6.438 mg/kg, respectively. The single-factor pollution index showed that Cd was moderately polluted, and Cr, Hg, As, and Pb were slightly polluted. The Nemerow pollution index showed that the overall heavy metal pollution was classified as moderately polluted. The accumulation of heavy metals in different vegetables varied greatly, and chard, crown daisy, chayote, pumpkin, eggplant, white radish, sweet potato, carrot, and potato were selected as the low-accumulator vegetables. The consumption of all vegetables except chayote poses both carcinogenic and noncarcinogenic risks; among them, the consumption of sweet potato leaves has the highest health risks. The local population needs to adjust plantation structure and change dietary habits, and government should strengthen the management of phosphorus chemical plant pollution.

     

海上钻井平台安全风险预警模型应用研究

2010年美国墨西哥湾“深水地平线”钻井平台爆炸和2011年我国蓬莱钻井平台井涌事故,引发社会各界对海上钻井平台安全问题的关注.介绍了海洋钻井平台的组成结构,对海洋钻井平台的危险源进行了系统辨识,试图通过对海上钻井平台作业现场危险因素加以观察,诊断、分析警源、警情,警兆,警级,结合专家意见,从人员、设施设备、安全管理、工程地质、海上环境等几个方面建立海上钻井平台安全风险预警体系,采用改进的层次分析法,得出指标权重,构建海洋钻井平台安全风险预警模型,得到量化的预警结果.并通过对某钻井平台的实例分析,提出安全风险的预控对策,以期本模型对海上钻井平台的事故的发生起到一定的防范作用.     

Biosorption of Cr（VI） by carbonized Eupatorium adenophorum and Buckwheat straw： thermodynamics and mechanism

High quality and low cost carbon can be prepared from Eupatorium adenophorum （E. adenophorum） and Buckwheat straw. The biosorbent was used for Cr（VI） removal. The effect of experimental parameters, such as pH, sorbent dosage and temperature were examined and the optimal experimental condition was determned. Solution pH is found influencing the adsorp- tion. Cr（VI） removal efficiency is found to be maximum （98%） at pH= 1. Langmuir and Freundlich adsorption isotherms were applicable to the adsorption process and their constants were evaluated. The adsorption data obtained agreed well with the Langmuir sorption isotherm model. The maximum adsorption capacities for Cr（VI） ranged from 46.23 to 55.19mg.g^-1 for temperature between 298 K and 308 K under the condition of pH = 1.0. Thermodynamic parameters such as free energy change （AG）, enthalpy （AH） and entropy （AS） indicate a spontaneous, endothermic and increased randomness nature of Cr（VI） adsorption. Studies found that the raw E. adenophorum and buckwheat straw mixed materials with simple treatment had a high efficiency for the removal of Cr（VI） and would be a promising adsorbent.     

傣乡的竹

走进傣乡这片神奇的土地,便走进了竹的世界。