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41.
以滴液成球法制备的壳聚糖凝胶球为基体,依次通过Mn2+印迹,交联和半胱氨酸接枝合成了Cys-Mn-CCTS-1、Cys-MnCCTS-2 2种吸附树脂,通过SEM扫描、FTIR光谱对材料的结构进行了表征,并进行了低浓度Mn2+的静态吸附实验。研究表明,两种吸附材料对Mn2+去除率均达到70%;在干扰离子Ca2+和Mg2+总浓度达到200 mg/L时,Cys-Mn-CCTS-2对Mn2+的去除效率仍达到71.7%,表现出了一定的抗干扰能力;当Co2+、Mn2+共存时,Cys-Mn-CCTS-1和Cys-Mn-CCTS-2对Mn2+的吸附容量随Co2+浓度增大而减小,Co2+对后者影响相对更大。  相似文献   
42.
陕北能源开发生态环境补偿对策研究   总被引:3,自引:0,他引:3  
本文从陕北能源开发入手,通过对生态破坏、经济损失的分析,论述了生态环境补偿的必要性和迫切性,提出了生态环境补偿的依据。从生态学的角度分析了生态的损失补偿是企业产品成本的构成部分,而不应是社会责任承担。阐明了补偿费征收管理办法主要应包括征收范围、征收机构、征收标准、管理使用和罚则等五个方面。  相似文献   
43.
垃圾压缩站压缩污水污染防治对策   总被引:3,自引:0,他引:3  
调查分析了广州市垃圾压缩站所产生的压缩污水的水质特征,预测了随着垃圾压缩站的普及产生的压缩污水总量以及所带来的水环境污染问题,提出了污染防治对策。  相似文献   
44.
沈阳和大连市居民血硒水平的评价   总被引:12,自引:0,他引:12  
采用新极谱法测定了沈阳和大连市健康居民的全血样品的含量。沈阳和大连市分别为296例和300例,全血硒含量分别为153.8±48.5μg/L和146.5±51.0μg/L。沈阳市男性159例,女性137例,全血硒含量分别为157.3±49.6μg/L和149.3±46.6μg/L。大连市男性159例,女性141例,全血硒含量分别为148.1±50.2μg/L和144.7±51.9μg/L。沈阳和大连市居民血硒水平处于营养状态,均比9年前血硒水平显著提高(p<0.001)。  相似文献   
45.
浅谈综放开采煤层自燃火灾及其防治   总被引:3,自引:1,他引:3  
综放开采作为一种特殊的采煤方法 ,其煤层自燃也有其自身的特点。笔者分析总结了综放开采煤层自燃的特点 ,以及各地点发生自燃火灾的相对难易程度 ,并从综放开采工艺和其他治理措施两个方面提出综放开采煤层自燃火灾预防和治理的方法和建议 ,指出改进综放开采工艺是预防煤层自燃火灾发生最为经济、有效的措施  相似文献   
46.
Coking coals are the important raw materials for the iron and steel industries and play an important role on its sustainable development, especially on the stamp-charging coke making with the characteristics of increasing the bulk density. There is a significance on the reasonable usage of the coking coal resource with the reduced production cost, improved efficiency of the economy to develop the stamp-charging coke making technology. Important effects of the density of coking coal on the coking and caking properties were investigated. In the article, the maximum values of swelling pressure and variation of Laowan gas coal and Xinjian 1/3 coking coal, Longhu fat coal and Didao coking coal, which were mined at Shenyang and Qitaihe respectively, were investigated under different bulk densities during the coking. The results showed that when the values of density increased from 0.85 ton/m3 to 1.05 ton/m3, for the Laowan gas coal, swelling pressure variation and even the maximum value changed slightly. The swelling pressure was 3.63 KPa when the density was improved to 1.05 ton/m3; for the Xinjian 1/3 coking coal, the values of swelling pressure changed significantly and the maximum values was 82.88 KPa with the density improved to 1.05 when the coal was heated to 600℃. The coke porosity, which was investigated by automatic microphotometer, decreased from 47.4% to 33.1% with the increasing of the density from 0.85 ton/m3 to 1.05 ton/m3, and the decreased value was 14.3%. Meanwhile, the pore structures of four cokes were characterized by an optical microscope.  相似文献   
47.
Long flame coal are abundant and widely distributed in China, but the resource utilization is quite low, the production efficiency is not high. Stamp-charging coke making technology can bend some long flame coal, which can reduce production cost and expand the coking coal resources. The long flame coal of different mass fraction is added into prime coking coal including fat coal from Longhu, 1/3 coking coal from Xinjian and coking coal from Didao in experiment. The swelling pressure is tested on-line detection using pressure sensor in coke making process, and the pores are observed by scanning electron microscopy. The results show that, the swelling pressure first increase and then decrease with the temperature increased and the maximum swelling pressure reduces gradually with mass fraction of the Long flame coal from Shenmu increased in coke making process. The SEM images of resultant coke display that the coke get more and more loose and the amount of pores is increased with mass fraction of the long flame coal from Shenmu increased. The amount pores and the pore diameter both is minimum for coking coal from Didao as prime coking coal under the same fraction of long flame coal.  相似文献   
48.
Coking coals are the important raw materials for the iron and steel industries and play an important role on its sustainable development, especially on the stamp-charging coke making with the characteristics of increasing the bulk density. There is a significance on the reasonable usage of the coking coal resource with the reduced production cost, improved efficiency of the economy to develop the stamp-charging coke making technology. Important effects of the density of coking coal on the coking and caking properties were investigated. In the article, the maximum values of swelling pressure and variation of Laowan gas coal and Xinjian 1/3 coking coal, Longhu fat coal and Didao coking coal, which were mined at Shenyang and Qitaihe respectively, were investigated under different bulk densities during the coking. The results showed that when the values of density increased from 0.85 ton/m3 to 1.05 ton/m3, for the Laowan gas coal, swelling pressure variation and even the maximum value changed slightly. The swelling pressure was 3.63 KPa when the density was improved to 1.05 ton/m3; for the Xinjian 1/3 coking coal, the values of swelling pressure changed significantly and the maximum values was 82.88 KPa with the density improved to 1.05 when the coal was heated to 600°C. The coke porosity, which was investigated by automatic microphotometer, decreased from 47.4% to 33.1% with the increasing of the density from 0.85 ton/m3 to 1.05 ton/m3, and the decreased value was 14.3%. Meanwhile, the pore structures of four cokes were characterized by an optical microscope.  相似文献   
49.
石油烃厌氧生物降解代谢产物的分析对于石油烃厌氧降解机制的研究、功能微生物的筛选以及微生物活动的原位监测具有指示性作用.综述了近年来石油烃厌氧生物降解代谢产物的研究进展.石油烃厌氧降解的初始活化方式主要包括脱氢羟基化、加延胡索酸以及羧化等.其中,加延胡索酸是不同种类的微生物通常采用的代谢方式.同时,将代谢产物按照气体、无机离子和有机酸进行分类,并针对各类物质特别是瞬时性、低浓度的有机酸类产物常采用的分析方法进行归纳.通过实例强调了代谢产物作为潜在生物标记物的应用,并对石油烃厌氧降解代谢产物分析方法的发展提出展望.图3参58  相似文献   
50.
产业转移对肇庆市水资源承载力的影响研究   总被引:1,自引:0,他引:1  
随着区域合作的不断深入,互补性产业转移和产业承接日益成为区域内经济合作的热点和重点,但产业转移过程中不可避免地存在着一定程度的污染转移。正确评价区域发展的承载力,对于协调区域资源与国民经济发展的关系具有重要意义。应用因子分析法对肇庆市2003年的水资源承载力进行分析,结果表明:影响肇庆市水资源承栽力的主要的三个因子分别是水资源开发利用水平、水体纳污能力和自来水工程供水能力。肇庆市承接产业转移工业园后的水资源承载力变化情况表明产业转移政策在促进当地经济发展的同时,对大部分地区水环境所造成的影响是可接受的。  相似文献   
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