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111.
This paper reviews the application of meso- porous transitional metal oxides in water treatment on basis of the catalysis and adsorption. Mesoporous transitional metal oxides are characterized by their intrinsic features, such as a high surface area, a highly ordered array of unidimensional pores with a very narrow pore size distribution, and highly dispersed active sites. Finally, the suggestions of further study on application are proposed.  相似文献   
112.
介绍了一种用于给倾角传感器提供恒温环境的小型高精度恒温箱的设计与实现.此恒温箱要求体积小、温度控制精度在±0.05℃以内.文中介绍了恒温箱的结构设计和温控算法并给出了详细的实验结构,证明了研制的这种高精度恒温箱不仅其控温精度高,且与同类产品比其体积小,安装调试方便.  相似文献   
113.
夏凡  梅凯  陆曦  佘步存 《环境工程学报》2010,4(12):2819-2822
采用移动床生物膜反应器(MBBR)和曝气生物滤池(BAF)结合工艺对有机腈类废水处理进行了小试研究,以考察有机物的降解规律。经过稳定运行2个月,在两级硝化液回流比R=200%,pH=7.5,HRT=3 d的情况下,进水COD、CN-、NH3-N、TN及BOD5浓度平均值分别为3 024、38、185、305和845 mg/L时,出水COD、CN-、NH3-N、TN及BOD5平均浓度为50、0.5、10、45和17 mg/L,去除率分别为98.2%、98.7%、94.2%、85.2%和98.0%,BOD/COD比值由0.29提高到0.34,达到了《江苏省化学工业主要水污染物排放标准》(DB32/939-2006)一级排放标准。  相似文献   
114.
In this study, a graphitic carbon nitride(g-C3N4) based ternary catalyst Cu O/Cu Fe2O4/gC3N4(CCCN) is successfully prepared thorough calcination method. After confirming the structure and composition of CCCN, the as-synthesized composites are utilized to activate persulfate(PS) for the degradation of organic contaminant. While using tetracycline hydrochloride(TC) as pollutant surrogate, the effects of initial p H, PS and catalyst ...  相似文献   
115.
通过采集某铬渣堆场周边不同距离、深度的土壤和地下水样品,研究了铬渣堆场周边土壤、地下水中六价铬的分布特征和污染状况,通过数据分析确定了铬渣堆场周边受铬污染的地下水和土壤的范围及污染程度,判断污染边界,为后续场地污染治理提供了基础资料。结果表明:铬渣堆场周边土壤地下水已受到严重铬污染,必须尽快采取有效措施对其进行治理修复,以保证当地的农业生产和人体健康。  相似文献   
116.
Goal, Scope and Background Transport of P from agricultural land contributes to the eutrophication of surface waters. Soil amendment is considered one of the best management practices (BMPs) to reduce P loss from sandy soils. Laboratory column leaching experiments were conducted to evaluate the effectiveness of different soil amendments in reducing P leaching from a typical sandy soil in Florida. Methods The tested amendments were CaCl2, CaCO3, Al(OH)3, cellulose, and mill mud, and applied at the rate of 15 g/kg for a single amendment and each 7.5 g/kg if two amendments were combined. Leaching was conducted every four days for 32 days, 250 mL of deionized water being leached for each column per leaching event. Leachates were collected from each leaching event and analyzed for reactive P, PO4-P, and macro and micro-elements. Results and Discussion Except for the soils amended with CaCl2, or CaCl2+CaCO3, reactive P and PO4-P leaching losses mainly occurred in the first three leaching events. Phosphorus leaching from the soils amended with CaCl2 or CaCl2+CaCO3 was less but more persistent than that of other amendments. Reactive Pleaching loss was reduced by 36.0% and 40.4% for the amendments of CaCl2, and CaCl2+CaCO3, respectively, as compared with chemical fertilizer alone, and the corresponding values for PO4-P were 70.8% and 71.9%. The concentrations of K, Mg, Cu, and Fe in leachate were also decreased by CaCl2 or CaCl2+CaCO3 amendment. Among the seven amendments, CaCl2, CaCO3, or their combination were most effective in reducing P leaching from the sandy soil, followed by cellulose and Al(OH)3, the effects of mill mud and mill mud + Al(OH)3 were marginal. Conclusions These results indicate that the use of CaCl2, CaCO3, or their combination can significantly reduce P leaching from sandy soil, and should be considered in the development of BMPs for the sandy soil regions. Recommendations and Outlook Most agricultural soils in south Florida are very sandy with minimal holding capacities for moisture and nutrients. Repeated application of fertilizer is necessary to sustain desired yield of crops on these soils. However, eutrophication of fresh water systems in this area has been increasingly concerned by the public. Losses of P from agricultural fields by means of leaching and surface runoff are suspected as one of the important non-point contamination sources. The benefits and effectiveness of soil amendment in reducing P losses from cropping production systems while sustaining desired crop yield need to be demonstrated. Calcium chloride, CaCO3, or their combination significantly reduce Pleaching from sandy soil, and should be considered in the development of BMPs for the sandy soil regions.  相似文献   
117.
微波活化对Ca(OH)2孔隙结构及脱氯性能的影响   总被引:1,自引:0,他引:1  
采用微波炉对一定质量的氢氧化钙样品进行活化,利用压汞仪考察了不同微波活化时间及脱氯反应前后的Ca(OH)2总比孔表面积、分段比表面积和孔径分布的变化,并在脱氯实验台上对脱氯效率进行实际测试.结果表明,微波活化存在一个最佳时间,在此时间内样品比孔表面积增大50%左右,而超过这一时间样品比表面积回复性减小;微波活化主要通过增加3~20 nm孔径段的微孔为样品提供更大比表面积;这些新增加的微孔在脱氯反应过程中被完全利用或消耗;最佳活化时间下的微波活化使Ca(OH)2在较低Ca/Cl摩尔比下获得更大脱氯效率,Ca/Cl摩尔比=4.1时,脱氯效率增加了20%.  相似文献   
118.
基于支付卡式问卷调研,运用条件价值评估法(CVM)结合二元Logistic回归模型、多元线性回归模型,分析上海市居民对生活垃圾治理的支付意愿(WTP)和影响因素。调研发现:(1)54.5%的受访者暂无WTP,主要原因是认为生活垃圾治理费用不应该由自己支付;(2)受访者的WTP与其文化程度呈正相关关系;(3)WTP的金额与年龄负相关,与在上海市居住年数、月收入正相关;(4)上海市居民生活垃圾治理的WTP金额为54.3元/月,占受访者人均月收入的0.72%。调研结果可为上海市未来制定垃圾收费政策提供参考。  相似文献   
119.
Environmentally Extended Input-Output(EEIO)tables have become a powerful element in supporting information-based environmental and economic policies.National-and provincial-level 10 tables are currently published by the National Bureau of Statistics of the People's Republic of China according to well-defined conventions.However,county-level 10tables are not provided as a rule by official statistics organizations.This paper conducts an overview of compiling EEIO tables for environmental and resources accounting at the county level and then answers several questions:First,what kind of data should be prepared for the compilation of county-level EEIO tables?Second,how can we set up comprehensive EEIO tables at the county level?Third,regarding the survey methods and the indirect modeling,which one should be chosen to build EEIO tables at the county level?Finally,what policy questions could such a table answer?EEIO tables at the county level can be used to predict the economic impacts of environmental policies and to perform trend and scenario analysis.  相似文献   
120.
以含锑烟尘为原料,经脱杂处理后,采用真空蒸发法制备了立方晶型纳米三氧化二锑,并用XRD衍射和SEM扫描电镜对产物三氧化二锑进行表征。结果表明,制备的三氧化二锑为立方晶型,颗粒粒径为35~100 nm。实验考察了脱杂时间对脱杂效果的影响;考察了蒸发温度、压强、蒸发时间3个因素对三氧化二锑颗粒粒度的影响。  相似文献   
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