Ce-MCM-41分子筛用于臭氧氧化对氯苯甲酸的活性评价

通过水热法合成了铈掺杂MCM-41(Ce-MCM-41)介孔分子筛,并将其用于臭氧氧化水中对氯苯甲酸(p-CBA).小角X射线衍射(XRD)、氮气吸附-脱附(BET)、紫外可见漫反射光谱(UV-Vis DRS)、透射电镜(TEM)表征结果表明,铈成功进入MCM-41分子筛骨架,以正四面体形式存在,且Ce-MCM-41保持了纯硅MCM-41有序的介孔结构,具有较高的比表面积;铈的掺杂显著提高MCM-41催化臭氧氧化对氯苯甲酸的活性,反应60 min后,TOC去除率由MCM-41的63%提高到86%(Si/Ce=60),而单独臭氧氧化仅为52%;铈的溶出仅为0.085 mg.L-1,较同样负载量的铈负载Ce/MCM-41的溶出(0.44 mg.L-1)有较大减少.催化剂重复使用3次后仍保持较高的活性,这表明Ce-MCM-41具有较好的活性和稳定性,是一种有前景的臭氧氧化催化剂.     

MCM - 41中孔分子筛对铜离子吸附性能的研究

以MCM-41中孔分子筛（简称MCM-41）为吸附剂,对含Cu^2＋的溶液进行了静态吸附实验。结果表明：MCM-41对Cu^2＋的吸附量较大,约为283．0mg／g;Cu^2＋的去除率随吸附液pH的增大和吸附温度的升高而增加;MCM-41对Cu^2＋的吸附性能符合Langmuir吸附方程的特征;Cu^2＋的吸附过程为自发的吸热吸附过程。     

MCM-41分子筛吸附罗丹明B的研究

通过水热法合成了MCM-41分子筛,通过XRD,N2吸附-脱附对样品进行了表征。以MCM-41分子筛作为吸附剂,以罗丹明B溶液模拟染料废水,进行了吸附脱色实验,考察了吸附时的pH值、温度、浓度、平衡时间等因素对吸附性能的影响。研究发现在较宽的pH值范围（3～9）和低温（5～20℃）时,MCM-41分子筛对于罗丹明B表现出优异的吸附性能,每克吸附质量可达到113～141mg。     

Preventing land loss in coastal Louisiana: estimates of WTP and WTA

A dichotomous-choice contingent-valuation survey was conducted in the State of Louisiana (USA) to estimate compensating surplus (CS) and equivalent surplus (ES) welfare measures for the prevention of future coastal wetland losses in Louisiana. Valuations were elicited using both willingness to pay (WTP) and willingness to accept compensation (WTA) payment vehicles. Mean CS (WTP) estimates based on a probit model using a Box-Cox specification on income was $825 per household annually, and mean ES (WTA) was estimated at $4444 per household annually. Regression results indicate that the major factors influencing support for land-loss prevention were income (positive, WTP model only), perceived hurricane protection benefits (positive), environmental and recreation protection (positive), distrust of government (negative), age (positive, WTA model only), and race (positive for whites).     

介孔分子筛MCM-41对污水中Cr(Ⅵ)吸附动力学研究

以介孔分子筛MCM-41为吸附剂,研究了水中Cr6+分别在不同pH,温度以及吸附时间的吸附行为。实验结果表明,pH为0,温度为35℃,吸附时间为3h,此时的吸附效果较好。吸附动力学分别拟合了Lagergren一级,二级反应模型,该吸附较符合Lagergren二级反应模型,相关系数高达0.9996。计算出饱和吸附量qe为995.76mg/g,二级反应速率常数k2为21.7689g/(mg·h)。该吸附反应是化学吸附且有多个吸附过程共同作用的结果。