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191.
建立一种土壤中壬基酚的提取和含量测定方法。土壤样品经二氯甲烷索氏提取、旋转蒸发仪浓缩蒸干后,用色谱流动相溶解。以色谱甲醇与高纯水(体积比为85:15)为流动相,经C18色谱柱分离,在检测波长277nm进行紫外光检测。土壤样品中4-壬基酚的捡出限为20ng/g,4-壬基酚混合标准检测相对标准偏差范围在2.39%-4.56%之间。加入标准溶液后,土壤中壬基酚的加标回收率为98.73%~101.78%,标准偏差小于2.97%。该方法简便快速,灵敏可靠,适用于土壤样品中环境类激素4-壬基酚的含量检测。  相似文献   
192.
姜春华  翟建 《环境科学与管理》2012,37(10):122-125,135
研究不同磁化时间、不同磁场强度以及催化氧化体系中各种影响因素对表面活性剂污水CODcr的去除率的影响。结果表明:在pH值3,H2O2加入量为0.5%(体积比),FeSO4.7H2O浓度为3 000 mg/L,反应10min,去除率达69.8%。在相同实验条件下,外加磁场强度分别为235.6 mT、357.3 mT、427.8 mT,CODcr的去除率可提高3.5%、8.4%、10.5%。  相似文献   
193.
本研究对太湖上游集水区重要城市常州城区河网的12条主要河流开展了城市主要河道沉积物中的重金属分布状况及特征调查,采用Hakanson生态风险指数法对沉积物中的主要重金属对所在水域的污染程度及对水域和周围环境造成的潜在风险影响进行了评价。结果显示,常州河道沉积物已受到严重污染,不同类型河道的沉积物污染程度趋势为:城区>郊区>城市外围河道,其中以Hg的污染最重。  相似文献   
194.
赤水河流域水资源保护与开发利用   总被引:1,自引:0,他引:1  
赤水河是长江上游干流唯一一条没有开发利用的支流,是长江上游珍稀特有鱼类自然保护区,并被誉为英雄河、美酒河、美景河,具有重要的保护价值。同时,赤水河具有丰富的水能资源,具有开发利用价值。由于赤水河流域水资源保护与开发过程中各种矛盾的存在以及赤水河为跨省界河流的特点,导致在赤水河流域水资源保护过程中存在一些困难。文章总结了赤水河流域的保护利用价值,剖析了赤水河流域水资源保护过程中存在的各种问题,提出了协调赤水河流域水资源保护与开发利用的对策措施。  相似文献   
195.
分析了输油管线增输后的新特点,采取了实现安全低耗输油的对策:增设水击超前保护系统、合理安排管线启停顺序。  相似文献   
196.
There are many watercraft and production accidents in the Three Gorges Reservoir Area (TGRA) of the Yangtze River in China every year. Accidents threaten the water quality of the 1085 km2 surface area of the TGRA and millions of local people if oil and chemical leakage were to occur. A water pollution management system for emergency response (WPMS ER) was therefore designed for the management of pollution in this area. An integrated geographic information system (GIS)-based water pollution management information system for the TGRA, called WPMS ER TGRA, was developed in this study. ArcGIS engine was used as the system development platform, and Visual Basic as the programming language. The models for hydraulic and water quality simulation and the generation of body-fitted coordinates were developed and programmed as a dynamically linked library file using Visual Basic, and they can be launched by other computer programs. Subsequently, the GIS-based information system was applied to the emergency water pollution management of a shipwreck releasing 10 tons of phenol into the Yangtze River during two hours. The results showed that WPMS ER TGRA can assist with emergency water pollution management and simulate the transfer and di usion of accidental pollutants in the river. Furthermore, it can quickly identify the a ected area and how it will change over time within a few minutes of an accident occurring.  相似文献   
197.
第五十六类无机碱 活性特点: 无机碱一般为金属氢氧化物.常见的无机碱包括碱金属氢氧化物、碱土金属氢氧化物等.其中最常用的为碱金属氢氧化物,如氢氧化钠、氢氧化钾等.  相似文献   
198.
灾害性天气影响下的交通气象服务进展研究   总被引:1,自引:0,他引:1  
翟雅静  李兴华 《灾害学》2015,(2):144-147,178
详细研究了各种灾害性天气气候如何对高速公路的运输及安全造成影响,以及由这些恶劣天气引起的交通事故造成的人员伤亡和财产经济损失。研究了国内外的交通气象服务现状,通过分析比较的方法找到了我国交通气象服务存在的一些不足。对如何更好发展交通气象服务提出了对策和建议,以期达到降低交通安全事故,提高高速公路的运输效率,减少财产经济损失和减少人员伤亡的目的,为我国的国民经济和社会发展做出贡献。  相似文献   
199.
A new technique whereby cellulase immobilized on aminated silica was applied to catalyze the degradation of dicofol, an organochlorine pesticide. In order to evaluate the performance of free and immobilized cellulase, experiments were carried out to measure the degradation efficiency. The Michaelis constant, Km, of the reaction catalyzed by immobilized cellulase was 9.16 mg/L, and the maximum reaction rate, Vmax, was 0.40 mg/L/min, while that of free cellulase was Km = 8.18 mg/L, and Vmax = 0.79 mg/L/min, respectively. The kinetic constants of catalytic degradation were calculated to estimate substrate affinity. Considering that metal ions may affect enzyme activity, the effects of different metal ions on the catalytic degradation efficiency were explored. The results showed that the substrate affinity decreased after immobilization. Monovalent metal ions had no effect on the reaction, while divalent metal ions had either positive or inhibitory effects, including activation by Mn2 +, reversible competition with Cd2 +, and irreversible inhibition by Pb2 +. Ca2 + promoted the catalytic degradation of dicofol at low concentrations, but inhibited it at high concentrations. Compared with free cellulase, immobilized cellulase was affected less by metal ions. This work provided a basis for further studies on the co-occurrence of endocrine-disrupting chemicals and heavy metal ions in the environment.  相似文献   
200.
● High fluorine is mainly HCO3·Cl-Na and HCO3-Na type. ● F decreases with the increase of depth to water table. ● High fluoride is mainly affected by fluorine-containing minerals and weak alkaline. ● Fluorine pollution is mainly in the north near Laizhou Bay (wet season > dry season). ● Groundwater samples have a high F health risk (children > adults). Due to the unclear distribution characteristics and causes of fluoride in groundwater of Mihe-Weihe River Basin (China), there is a higher risk for the future development and utilization of groundwater. Therefore, based on the systematic sampling and analysis, the distribution features and enrichment mechanism for fluoride in groundwater were studied by the graphic method, hydrogeochemical modeling, the proportionality factor between conventional ions and factor analysis. The results show that the fluorine content in groundwater is generally on the high side, with a large area of medium-fluorine water (0.5–1.0 mg/L), and high-fluorine water is chiefly in the interfluvial lowlands and alluvial-marine plain, which mainly contains HCO3·Cl-Na- and HCO3-Na-type water. The vertical zonation characteristics of the fluorine content decrease with increasing depth to the water table. The high flouride groundwater during the wet season is chiefly controlled by the weathering and dissolution of fluorine-containing minerals, as well as the influence of rock weathering, evaporation and concentration. The weak alkaline environment that is rich in sodium and poor in calcium during the dry season is the main reason for the enrichment of fluorine. Finally, an integrated assessment model is established using rough set theory and an improved matter element extension model, and the level of groundwater pollution caused by fluoride in the Mihe-Weihe River Basin during the wet and dry seasons in the Shandong Peninsula is defined to show the necessity for local management measures to reduce the potential risks caused by groundwater quality.  相似文献   
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