超声波有机改性凹凸棒土的苯酚吸附性能研究

采用超声波技术,对凹凸棒土进行有机改性,提高凹凸棒土的苯酚吸附能力,比较了不同的阳离子表面活性剂的改性效果,并且通过正交实验得出了超声波改性的最优化工艺条件为：十八烷基三甲基氯化铵的添加比例为35 mmol/100 g,超声波处理时间10 min,屏极电流0.5 A.在此条件下,苯酚去除率可达酸处理凹凸棒土的80倍以上,是搅拌有机改性的1.5倍.     

离子交换纤维对重金属的吸附研究

采用自制强酸性阳离子交换纤维对镉、铅离子的吸附性能进行了初步研究。实验结果表明 ,强酸性阳离子交换纤维对镉、铅离子具有较好的吸附能力 ,其最大吸附容量分别为 2 0 6.6mg g和 10 5 .5mg g ;吸附速度快 ,2 0min即可达到平衡。用Langmuir方程对其吸附等温线进行回归 ,结果显示实测值与理论方程具有较好的一致性     

Mg-AI型水滑石对水溶液中F^-的吸附

采用水热法合成Mg-AI型水滑石（LDHs），研究LDHs及其焙烧产物C-LDHs对水溶液中F^-的吸附行为，并用X射线衍射和热重分析对LDHs，C-LDHs以及吸附F^-后的C-LDHs（R-LDHs）的结构和性质进行了表征．结果表明：LDHs对水溶液中的F^-基本没有吸附，而C-LDHs对F^-有较大的吸附容量，同时，酸性的增强有利于C-LDHs对F^-的吸附．C-LDHs对F^-吸附4h后可达到吸附平衡．通过吸附F^-，C-LDHs的结构由吸附前的混合氧化物固溶体恢复到层状结构，表明C-LDHs对水溶液中F^-的高吸附性能是因为其具有较强的“记忆效应”．     

Modelling dynamics of managed tropical rainforests—An aggregated approach

The overuse of rainforests in the last century and its consequences necessitate a rethinking of logging policies. To this end models have been developed to simulate rainforest dynamics and to allow optional management strategies to be evaluated. Parameterisation of presently existing models for a certain site needs a lot of work, thus the parameterisation effort is too high to apply the models to a wide range of rainforests. Hence, in this paper we introduce the simplified model FORREG using the knowledge we have gained from a more complex model, FORMIX3-Q.     

Oviposition by butterflies on young leaves: Investigation of leaf volatiles

Summary Various butterflies select young foliage on which to lay their eggs; volatiles emitted by young and old leaves have been compared (by sorption enrichment, followed by GC-MS) to gauge possible qualitative and quantitative differences between the two age groups. The plants investigated are cabbage (Brassica oleracea), two milkweeds (Asclepias syriaca andA. curassavica), the bitter orange (Citrus aurantium) and the lime (C. aurantiifolia). The chemical compounds identified belong to three classes, isoprenoids, fatty acid derivatives and benzenoids. Quantitative differences were found between young and old leaves, of which a few may be characteristic of young leaves only. Thirty-four single trials withDanaus plexippus exposed to volatiles from young and old leaves are recorded.     

硝基多环芳烃的正辛醇—水分配系数

用摇瓶法测定了九种硝基多环芳烃的正辛醇-水分配系数,研究发现用Leo碎片法可以较好地估算NO_2-PAHs化合物的正辛醇-水分配系数。在正辛醇-水分配系数(K_(ow))与水溶解度(S)之间建立了相关方程: lgK_(ow)=-0.925lgS-0.00697(mp-25)+4.164(S用mg/l表示时); lgK_(ow)=-0.885lgS-0.00727(mp-25)+4.815(S用mol/m~3表示时)。     

CTMAB-膨润土吸附水中有机物的性能及应用

本文用溴化十六烷基三甲铵(CTMAB)-改性膨润土,研究了CTMAB-膨润土吸附水中α-萘胺、β-萘胺、α-萘酚、硝基苯和苯胺的性能和适宜条件.结果表明,CTMAB-膨润土对水中有机物的吸附能力与CTMAB在膨润土上的实际交换量有关,也与作用方式和有机物辛醇-水分配系数有关.CTMAB-膨润土对五种有机物的去除率顺序为:α-萘胺、β-萘胺、α-萘酚>硝基苯>苯胺.     

活性矸对硫、氟、铬阴离子吸附的研究

本文对活性矸-硫、活性矸-氟、活性矸-铬(Ⅵ)三种吸附系统进行了研究.结果表明:活性矸静态等温吸附符合Freundlich吸附等温式;静态吸附动力学可用Bangharm吸附速率方程描述;利用Body公式可确定活性析矸-氟吸附系统的液相有效扩散系数.     

单甲脒在土壤中的吸附

用批量平衡法研究了单四脒酸盐的活性部分－单甲脒在不同类型土壤中的吸附行为，获得了单甲脒的单位土壤有机质吸附常数（Ｋｏｍ）为２８４和吸附自由能变化量为１３．９９ｋＪ．ｍｏｌ＾－１的实验数值，研究表明，单甲脒在土壤中吸附符合Ｆｒｅｕｎｄｌｉｃｈ经验公式，其在土壤中的吸附系数Ｋｄ与土壤中有机质含量和阳离了交换容量均显著正相关。     

Sorption of Cu and Zn by bone charcoal

Bone charcoal is being developed as a treatment for decontaminating polluted water. In particular, its potential to adsorb metal species from contaminated water supplies is being examined. In this study, bone charcoal was used in batch and column experiments designed to investigate the sorption of two cationic metals Cu and Zn. The data from batch experiments fitted the Langmuir isotherm and so theoretical maximum binding capacities could be obtained. These values were compared with experimental values derived from the column experiments. The mechanisms involved in the immobilisation were also investigated.