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111.
聚合物在粘土及钻井液固体颗粒表面的吸附   总被引:1,自引:0,他引:1  
围绕废弃钻井液的处理,采用非分散红外TOC仪测聚合物吸附量,研究了聚合物PAM、PHP、FA367、CPAM在粘土及钻井液固体颗粒表面的吸附特性,研究结果表明聚合物在粘土颗粒表面的吸附是高度不可逆的,聚合物高分子与粘土因氢键、静电及嵌入三种相互作用方式而吸附,阳离子型聚合物絮凝剂在钻井液固体颗粒表面比阴离子和非离子型絮凝剂有高得多的吸附性能,废弃钻井液的絮凝主要以“吸附架桥”机理为主。  相似文献   
112.
A respirometric method was developed to measure the mineralization of polymeric materials in a matured compost environment. For the purpose of evaluating the method, results obtained for the mineralization of glucose and cellulose are presented. The matured compost, in addition to supplied nutrients, micronutrients, and an inoculum, serves as the matrix which supports the microbial activity. Recovery of the substrate carbon in the form of carbon dioxide from the glucose and cellulose added to test vessels was 68 and 70%, respectively. A statistical evaluation of the results obtained on substrate mineralization was carried out and showed acceptable reproducibility between replicate test vessels and test runs. The testing protocol developed has the following important characteristics: (1) the test reactors are maintained at 53 °C at a high solids loading (60% moisture), which has certain characteristics that are similar to a thermophilic compost environment; (2) the test matrix providing microbial activity is derived from readily available organic materials to facilitate reproducibility of the method in different laboratories; (3) the equipment required to perform this test is relatively inexpensive; and (4) the information obtained on polymer mineralization is vital to the study and development of biodegradable polymeric materials.Guest Editor: Dr. Graham Swift, Rohm & Haas.  相似文献   
113.
ABSTRACT: The Applachicola River basin in northwest Florida covers an area of 3,100 square kilometers. Fifteen percent of the area is a dense bottomland hardwood forest which is periodically flooded. The annual leaf-litter fall from the flood-plain trees is a potential source of nutrients and detritus which eventually can flow into Apalachicola Bay. Transport of such material is dependent on the periodic inundation of the flood plain. The U.S. Geological Survey Apalachicola Rim Quality Assessment measured a total organic carbon flux of 2.1 × 105 metric tons during the one-year period from June 3, 1979, to June 2,1980. Fluxes of total nitrogen and phosphorus during the same year were 2.1 × lo4 and 1.7 × lo3 metric tons, respectively. Flood characteirstics, such as prior hydrologic conditions, extent, and timing, are important in determining the amount and forms of materials transported. The 1980 spring flood produced a fourfold discharge increase over the annual mean outflow of 800 cubic meters per second. Nutrient concentrations varied little with discharge, but the 86-day spring flood accounted for 53, 60, 48, and 56 percent of the annual flux of total organic carbon, particulate organic carbon, total nitrogen, and total phosphorus, respectively. In 1980, the flood peaks, rather than the rise or recession, accounted for maximum nutrient and detritus transport.  相似文献   
114.
绿色高分子及其发展现状   总被引:1,自引:0,他引:1  
本文介绍了高分子材料的用途及造成的危害,指出研究和使用绿色高分子材料的紧迫性和重要性,绿色高分子的要求、制造和应用,同时叙述了目前绿色高分子领域取得的进展和成就。  相似文献   
115.
本文综述了高分子材料在生产过程、使用过程及其废弃物所带来的危害,以及解决危 害的对策。  相似文献   
116.
A review of the difficulties associated with the definition of coastal flood frequencies and magnitudes leads to a recognition that there is considerable doubt in many parts of the world as to the precise nature of this particular hazard. Similarly, a review of the sea-level measurements that have been used to indicate a response to global warming shows that there is uncertainty about the amount of other controlling influences. What is clear, however, are that past management decisions about human endeavours in the coastal zone (including flood defences, occupance of flood-prone lands, extraction of ground water and natural gas) have had an impact on relative land and sea levels and have done more to increase the risk of coastal flooding than can be assigned so far to global warming. In addition, these changes induced by human activity may render inappropriate calculations of coastal-flood frequencies based on historical records since the latter relate to a period of time when the controls on flooding may have been very different.  相似文献   
117.
A block copolymer {P[(R,S)-HB-b-EG]} of atactic poly[(R,S)-3-hydroxybutyrate] {P[(R,S)-HB]} and poly(ethylene glycol) (PEG) was prepared by the ring-opening polymerization of -butyrolactone in the presence of a macroinitiator (PEG/ZnEt2/H2O) which had been produced by the reaction of ,-dihydroxy PEG ( n=3000) with ZnEt2/H2O (1/0.6) catalyst. The block copolymer ( n=10,500, w/ n=1.2) was an A-B-A triblock copolymer comprising atactic P[(R,S)-HB] (A) and PEG (B) segments. The miscibility, physical properties, and biodegradability of binary blends of microbial poly[(R)-3-hydroxybutyrate] {P[(R)-HB]} with the block copolymer P[(R,S)-HB-b-EG] has been studied. The glass-transition temperature (T g) data showed that the P[(R)-HB]/P[(R,S)-HB-b-EG] blend was miscible in the amorphous state. The P[(R)-HB] film became flexible and tough by means of blending with P[(R,S)-HB-b-EG] block copolymer. The enzymatic degradation of blend films was carried out at 37°C and pH 7.4 in a 0.1M phosphate solution of an extracellular PHB depolymerase fromAlcaligenes faecalis. The enzymatic degradation took place solely on the surface of the blend films.  相似文献   
118.
试论洪涝对水稻的影响   总被引:8,自引:2,他引:8  
洪涝灾害是我国主要的农业气象灾害之一,水稻遭受洪涝灾害的概率较大,研究洪涝对水稻的影响具有重要的意义。通过现场试验,对水稻不同生长阶段遭受洪涝灾害的影响和不同温度下遭受淹浸后的影响进行了研究,并用数理统计方法对水稻遭受淹浸后,其产量的一系列变化作了定量的分析。  相似文献   
119.
浅谈混凝剂在气田水处理中的应用   总被引:1,自引:1,他引:1  
雷彬  江丽  詹燕 《油气田环境保护》2005,15(1):12-14,59
在重庆气矿气田水处理中加入了聚合氯化铝和聚丙烯酰胺,其应结果表明,这两种絮凝剂配合使用的效果较好,能达到石油企业废水回注指标(pH值为6~9,SS小于30mg/L,石油类物质少于10mg/L)。分析了两者单独使用的处理结果,针对目前使用中存在的问题,指出应注意的事项,并对今后重庆气矿气田水处理运行中混凝剂的使用提出了建议。  相似文献   
120.
曲华  况明生  姜世龙  孙秀峰 《灾害学》2005,20(2):106-109
洪涝灾害是重庆市主要自然灾害之一,每年带来巨大的经济损失和人员伤亡,严重制约着重庆市社会、经济的可持续发展.本文在大量研究的基础上,分析了重庆市洪涝灾害的特点,总结了历年来的洪涝灾害及造成的损失,最后针对洪涝灾害的特点提出建立重庆市洪涝灾害管理系统,并对该系统作了详细分析.  相似文献   
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