新型磁性聚谷氨酸吸附剂对水中Pb2+的吸附去除

德岛大学安澤幹人首次利用γ-PGA在Fe3O4磁性纳米颗粒上进行涂层,制得了γ-聚谷氨酸-Fe3O4磁性纳米颗粒（PG-M）.本实验利用透射电镜以及扫描电镜对PG-M吸附剂的形貌进行了分析,发现PG-M与未涂层的Fe3 O4具有相似的形状以及大小,均为不规则的层状结构,且晶粒直径在120～320 nm之间;实验中针对性地对水溶液中Pb2＋进行了吸附探讨.在振荡实验中,通过主要参数的变化（pH值、吸附时间、竞争离子浓度、腐殖酸浓度）,得到如下结果：吸附最佳pH值为7.0;吸附量随着吸附时间的延长而增长,吸附平衡时间为45 min;Na＋对PG-M去除Pb2＋没有很强的干扰性,而Ca2＋则显示出一定的干扰作用;腐殖酸对吸附效果的影响是复杂的,表现为先增强吸附效果,随后降低吸附效果;最佳条件时Pb2＋的最大吸附量为93.3 mg/g.PG-M对Pb2＋的吸附均能较好地符合Freundlich和Langmuir等温吸附模型,其中Langmuir方程能更好地描述PG-M的吸附特征,说明PG-M在水溶液中对金属离子的吸附为单分子层吸附.PG-M吸附符合准二级动力学模型（r2〉0.99）.不同浓度的HCl和HNO3溶液的再生实验发现,0.1 mol/L的HCl溶液作为吸附再生液,可取得较好的再生效果.表明PG-M是可再生的,具有较好的经济性和可持续性.     

土地利用方式改变对红树林沉积物中营养元素含量的影响

以广西、广东、海南等地代表性红树林湿地为对象,研究红树林湿地利用方式的改变对沉积物有机碳、总硫、总氮和总磷等营养元素的含量变化和影响,结果表明：1）广东和海南红树林区总氮和总磷变化相似,均为：沉积物〉农田〉鱼塘〉光滩,广西大冠沙稍有不同,光滩的氮磷含量最低;有机碳和总硫含量各地稍有差异,但是红树林沉积物中的有机碳,总硫...     

离子色谱法测定无组织废气中溴化氢浓度

探讨无组织废气中溴化氢的测定方法。采样方法参照环境空气中氯化氢的采样方法,用淋洗液做吸收液,用大型气泡吸收管作收集器,点位设置按照《大气污染物综合排放标准(》GB16297-1996)附录C给出的无组织排放监控点设置方法进行;分析方法使用离子色谱法测定,分离度较高,相对标准偏差为1.7%～1.9%,加标回收率为93.8%～97.6%,溴离子的检测限为0.02μg/ml,当采样体积为60 L时,无组织废气中溴化氢的检出限为0.003 mg/m3。     

pH和共存阳离子对草莓茎吸附水体氨氮的影响

为了开发新型氨氮吸附剂和探讨环境因素对氨氮吸附的影响,以草莓茎为吸附材料,通过批平衡法研究了不同初始pH、共存阳离子、初始浓度和温度下氨氮去除的特点.结果表明,等温吸附符合Langmuir和Freundlich这2种模型,理论最大吸附量qm在15、25和35℃下分别为3.05、4.24和4.79 mg.g-1.温度升高有利于草莓茎对氨氮的吸附.草莓茎吸附氨氮最适初始pH为4～8.低pH减少草莓茎表面负电荷,高pH减少溶液中NH 4+的含量,都减少氨氮的吸附.草莓茎对溶液pH的缓冲则缓和了两者对氨氮吸附的影响.共存阳离子K+、Na+、Ca2+、Mg2+对草莓吸附铵离子没有竞争作用,而Zn2+、Al3+则由于其水解降低溶液的pH而显著降低草莓茎对氨氮的吸附.草莓茎吸附氨氮的应用pH范围较广且不易受废水中常见金属阳离子的干扰,说明草莓茎不仅可以作为废水中氨氮的吸附剂原料,而且较大多数矿物原料还有其自身的优势.     

次氯酸钠氧化消除水中BPA的影响因素和动力学

采用常用消毒剂次氯酸钠对内分泌干扰物双酚A（BPA）的氧化消除及动力学规律进行研究,考察了加氯量、BPA初始浓度、pH值、Br^-浓度和温度各因素对降解效果的影响.结果表明,次氯酸钠对BPA的氧化降解过程符合拟一级反应动力学;pH值对该降解反应影响较大,当pH为8～9时,BPA与 HOCl的反应速率达到最大为0 .544 3　min^-1;溶液中存在Br^-会加快BPA的降解,并且其整体反应不符合拟一级动力学规律,随着Br^-浓度的增加,BPA降解得越快;温度对该降解反应的影响较大并且符合Van't Hoff规则,提高反应温度,有利于氯对BPA的降解.     

V_2O_5-TiO_2离子存储电极薄膜的溶胶-凝胶法制备与性能研究

利用无机溶胶-凝胶技术制备了V2O5-（TiO2）x离子存储电极薄膜。采用X射线衍射（XRD）、原子力显微镜（AFM）、Raman光谱、循环伏安法（CV）和紫外-可见光透射光谱分别研究了复合薄膜的微观结构、化学计量、锂离子注入性能以及光学性能。结果表明复合薄膜具有V2O5的层状结构,其c轴方向的结构取向性有所降低;颗粒尺寸和表面粗糙度显著减小;同时TiO2的复合导致薄膜中V2O5的化学计量发生偏移,氧空位数量增多。当x=0.2时,薄膜具有相对较高的离子存储容量及循环稳定性,并且在离子注入/脱出状态均获得相当高的可见光透过性。     

春季黄渤海大气气溶胶的离子特征与来源分析

于2010年春季在黄海、渤海海域采集大气气溶胶总悬浮颗粒物（TSP）样品,并运用离子色谱法对其中主要的水溶性阴离子（Cl-、NO3-、SO24-、CH3SO3-（MSA））和阳离子（Na＋、K＋、NH4＋、Mg2＋、Ca2＋）浓度进行了测定.分析结果显示,黄海、渤海气溶胶样品中主要水溶性离子总浓度分别为10.2～47....     

Removal of copper ions from aqueous solution by calcium alginate immobilized kaolin

Kaolin has been widely used as an adsorbent to remove heavy metal ions from aqueous solutions. However, the lower heavy metal adsorption capacity of kaolin limits its practical application. A novel environmental friendly material, calcium alginate immobilized kaolin (kaolin/CA), was prepared using a sol-gel method. The e ects of contact time, pH, adsorbent dose, and temperature on Cu2+ adsorption by kaolin/CA were investigated. The Langmuir isotherm was used to describe the experimental adsorption, the maximum Cu2+ adsorption capacity of the kaolin/CA reached up to 53.63 mg/g. The thermodynamic studies showed that the adsorption reaction was a spontaneous and endothermic process.     

Transport and fate of mercury under different hydrologic regimes in polluted stream in mining area

Seepage from Hg mine wastes and calcines contains high concentrations of mercury (Hg). Hg pollution is a major environmental problem in areas with abandoned mercury mines and retorting units. This study evaluates factors, especially the hydrological and sedimentary variables, governing temporal and spatial variation in levels and state of mercury in streams impacted by Hg contaminated runo . Samples were taken during di erent flow regimes in theWanshan Hg mining area in Guizhou Province, China. In its headwaters the sampled streams/rivers pass by several mine wastes and calcines with high concentration of Hg. Seepage causes serious Hg contamination to the downstream area. Concentrations of Hg in water samples showed significant seasonal variations. Periods of higher flow showed high concentrations of total Hg (THg) in water due to more particles being re-suspended and transported. The concentrations of major anions (e.g., Cl??, F??, NO3?? and SO4 2??) were lower during higher flow due to dilution. Due to both sedimentation of particles and dilution from tributaries the concentration of THg decreased from 2100 ng/L to background levels (< 50 ng/L) within 10 km distance downstream. Sedimentation is the main reason for the fast decrease of the concentration, it accounts for 69% and 60% for higher flow and lower flow regimes respectively in the upper part of the stream. Speciation calculation of the dissolved Hg fraction (DHg) (using Visual MINTEQ) showed that Hg(OH)2 associated with dissolved organic matter is the main form of Hg in dissolved phase in surface waters in Wanshan (over 95%).     

Application of magnetic particles modified with amino groups to adsorb copper ions in aqueous solution

A magnetic adsorbent can be easily recovered from treated water by magnetic force,without requiring further downstream treatment.In this research,amine-functionalized silica magnetite has been synthesized using N-[3-(trimethoxysilyl)propyl]-ethylenediamine(TPED) as a surface modification agent.The synthesized magnetic amine adsorbents were used to adsorb copper ions in an aqueous solution in a batch system,and the maximum adsorption was found to occur at pH 5.5 ± 0.1.The adsorption equilibrium data fitted t...