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961.
纤维素基吸附剂——绿色、经济的水处理材料   总被引:1,自引:0,他引:1  
田野  孟令蝶  吴敏  黄勇 《环境化学》2011,30(1):326-330
介绍了一类基于天然纤维素的水处理用吸附剂.对纤维素修饰羧基等阴离子基团,可以用来吸附水中的重金属阳离子(如cd(2+)、Cu(2+)、Hg(2+)、Ni(2+)、Pb(2+).对纤维素修饰铝铁或胺基等成分,可以吸附水中含砷阴离子、氟离子等有害阴离子.在纤维素上修饰疏水链,可以吸附水中氯苯、染料等危害健康的有机物.  相似文献   
962.
微生物砷还原机制的研究进展   总被引:2,自引:1,他引:1  
砷是一种剧毒物质,环境中的砷对人体健康存在潜在威胁,因此长期以来备受关注.微生物的各种代谢过程对砷在环境中的归趋起着重要作用,其中砷还原微生物能将吸附于固体矿物中的As(Ⅴ)还原为可溶性强的As(Ⅲ),使砷进入液相,从而加剧了地下水等饮用水源的砷污染.论文主要介绍了两种微生物砷还原机制(异化砷还原和细胞质砷还原)在作用...  相似文献   
963.
The environmental risk of aquatic phosphorus (P) critically depends on its mobility and bioavailability, both of which are greatly affected by the size distribution and composition of P. The size distribution (particulate, colloidal and truly dissolved phase) of P, composed of molybdate reactive P (MRP) and molybdate unreactive P (MUP), was determined at twenty-three typical sections of the East Tiao River, China in the plum rain season. Results indicated particulate P was dominant followed by the truly dissolved P, while colloidal P was quantitatively the lowest in the whole river. From upstream to downstream, particulate P sharply increased, along with a slight decrease of truly dissolved P. However, colloidal P remained at a relatively stable level in the whole river, ranging from below detection limit to 0.025 mg L(-1), 0 to 13.4% of total P (TP). Furthermore, colloidal MRP exhibited a rising trend downriver as compared to upriver, with the notable transfer of MRP from the truly dissolved phase to particulate and colloidal phases. Particle concentration effect for colloids, observed in the study of MRP distribution, further corroborated the role of colloids in MRP solid/liquid partitioning. These observations, in this large-scale field investigation, fitted the "colloidal pumping" hypothesis. It may be concluded that colloids act as the intermediate and buffer in the dynamically balanced transfer of P from truly dissolved phase to large particulate phase, having a significant role in size distribution of P.  相似文献   
964.
Water quality parameters including TOC, UV(254), pH, chlorine dosage, bromide concentration and disinfection by-products were measured in water samples from 41 water treatment plants of six selected cities in China. Chloroform, bromodichloromethane, dibromochloromethane, dichloroacetic acid and trichloroacetic acid were the major disinfection by-products in the drinking water of China. Bromoform and dibromoacetic acid were also detected in many water samples. Higher concentrations of trihalomethanes and haloacetic acids were measured in summer compared to winter. The geographical variations in DBPs showed that TTHM levels were higher in Zhengzhou and Tianjin than other selected cities. And the HAA5 levels were highest in Changsha and Tianjin. The modeling procedure that predicts disinfection by-products formation was studied and developed using artificial neural networks. The performance of the artificial neural networks model was excellent (r > 0.84).  相似文献   
965.
梁冰  李野 《防灾减灾工程学报》2011,31(2):180-184,195
井下瓦斯事故严重威胁着煤矿的安全,研究煤与瓦斯耦合作用规律并采取相应措施可以有效地防止事故发生.考虑瓦斯气体的可压缩性和吸附、解吸特性,假设瓦斯气体在煤体孔隙中的流动遵循Darcy定律,建立了考虑爆破因素的煤与瓦斯流固耦合数学模型,并利用comsol对其求解.结果表明:炮掘对煤体的破坏能力大于机掘;炮掘工艺下,爆破应力...  相似文献   
966.
程士兵  叶姜瑜  王云仙 《环境工程》2013,(Z1):716-720,728
采用TGGE(Temperature gradient gel electrophoresis)方法对水源热泵水体的细菌群落结构进行了分析,首先提取水体微生物的总DNA,扩增16S V3区片段,然后进行TGGE分析。TGGE图谱的初步分析结果表明,安康湖水样中的细菌丰富度较高。在空调制冷期,细菌群落结构波动较大;而在空调制热期,细菌群落结构波动较小,说明夏季空调制冷期对水体的影响较大。相似性及聚类分析表明,空调运行的持续时间的长短及运行负荷的大小决定热泵尾水排放所影响的水域范围,尤其是对取水口处的影响。序列分析结果显示,水体中细菌属于3大类群:变形杆菌(Proteobacteria)、厚壁菌(Firmicutes)和拟杆菌(Bacteroides)。  相似文献   
967.
Environmental Science and Pollution Research - One of the main challenges of electrochemical Fenton-based processes is the treatment of organic pollutants at near-neutral pH. As a potential...  相似文献   
968.
It is difficult to realize the transformation from traditional economy industrial system to circular economy industrial system. Regarding primary raw materials as the indicators, the industrial system has been specified according to the divergence among the indicators and the circular utilization modes. In comparison with the association among industrial systems, the relationship among industrial sub-systems is named as industrial cross-linking in this paper. The industrial system which could completely utiLize and recycle the indicators shouM be increased and strengthened, and the circular economy industrial system with complete industrial association and industrial cross-linking should also be constructed. Taking the development of circular agricultural system basing on the traditional agricultural system as an example, the traditional agricultural products are regarded as the indicators which have been divided into foodstuff and crop straws which are used to produce food and articles for use, Like fertilizer, energy and papers etc. The way to construct the circular agricultural industrial system is to increase the industrial systems that could utilize the products generated from crop straws, feces and other castoffs and transform the wastewater and other trucks into environmental friendly products. It has also been pointed out that the construction of circular economy industrial system is conducive to the foundation of circular industrial economics and the establishment of the construction layout of circular economy and the application schemes. Suggestions to the theoretical and practical work of the next step have also been brought forward in this paper.  相似文献   
969.
港口资源的开发对区域经济社会的发展具有重要意义。本文着重分析了珲春防川建立自由港的国内外环境特点:(1)港口位于东北亚轴心与经济枢纽部位;(2)环日本海各国间存在着较强的资源、技术、劳动力、资金等生产要素的不平衡;(3)建港地区的开发已经令周边各国瞩目;(4)建港地区具有开发的内在优势。提出珲春防川自由港类型选择及建设步骤。对东北地区的开发和我国全方位开放具有重要的参考价值。  相似文献   
970.
人口,资源,环境与发展系统研究的基本思路   总被引:1,自引:0,他引:1  
人口、资源、环境与发展问题相互关联,构成了一个复杂巨系统。应用系统科学的思想方法研究这个复杂巨系统,是当前最令人注目的重大学术领域。本文探讨了这一系统研究的范围框架、基本内容结构和研究方法,建立了针对我国实际问题的系统概念模型。这一概念模型首次把人口、资源、环境、经济、科技、教育、文化等基本要素组织在一个完整的社会核算体系中。  相似文献   
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