Experimental Study of Factors Controlling Sorption of Heavy Metals on Ariake Clay and Implication for Practice

A series of batch tests have been presented to investigate the effects of solid-solution contact time, solid:solution ratio, and pH of solution on sorption of Cd²⁺ and Pb²⁺ on Ariake clay from Kyushu region of Japan. The results show that, among the three investigated factors, solid:solution ratio (SD/SN) seems to be the crucial controlling factor. The Freundlich sorption parameters determined from the batch tests were applied to a typical field landfill in which the Ariake clay was used as soil barrier. The impacts of the landfill were assessed by numerical analysis. Based on the analysis result, the significance of selecting proper solid:solution ratio for determining sorption parameters from batch test has been discussed.     

内蒙古哈素海区域高砷地下水化学特征及其成因

哈素海区域高砷地下水对当地居民饮用水安全造成严重威胁, 揭示其形成演化机制对科学合理的开发利用水资源、保障居民身体健康具有重要意义。本文在水文地质调查的基础上, 应用Piper三线图、PHREEQC的砷形态计算及相关性分析等方法, 研究高砷地下水化学特征、构建砷形态模型(SM)和砷吸附模型(HSM), 以揭示高砷地下水的成因机制。结果表明, 研究区砷浓度为0.2~231.5 μg/L, 高砷区主要分布在大青山以南的冲湖积平原区; 地下水砷的类型以As(Ⅲ)为主, SM分析显示优势形态为H3AsO3, HSM分析显示存在Hfo_wH2AsO3和H3AsO3两种主要形态。地下水中的砷化物可能来源于山区富砷岩石的风化溶解以及第四系富砷河湖相沉积物; 研究区河湖相沉积环境是高砷水形成的前提, 有机质分解主导的还原环境是导致砷从含水介质释放到地下水中的主要因素, 弱碱性环境和HCO– 3的竞争吸附也会引起砷的释放。     

The role of organic matter in the sorption capacity of marine sediments

Past studies have suggested that desiccation enhances hydrophobicity of salt marsh sediment, and that drying and rewetting sediment can be used to investigate sorption mechanisms of amino acids and other organic compounds [Liu, Z., Lee, C., 2006. Drying effects on sorption capacity of coastal sediment: The importance of architecture and polarity of organic matter. Geochim. Cosmochim. Acta 70, 3313–3324]. Here we further develop this technique to study sorption of hydrophobic and hydrophilic organic compounds in a wide range of marine sediments. Our results show that hydrophilic compounds sorb strongly to wet coastal sediments; in dried sediments, sorption of hydrophilic compounds decreases, while sorption of hydrophobic compounds is greatly enhanced. Small compounds with aromatic rings sorb more in dried than wet coastal sediments, suggesting that aromatic groups have a stronger effect on sorption than polar groups like amino and carboxyl moieties. Sorption of lysine, glutamic acid and putrescine decreases greatly when sediment is pretreated with KCl, indicating the importance of cation ion exchange. However, α-amino acids sorb much more than corresponding β- or γ-amino acids, and l-alanine sorbs more than d-alanine, suggesting that amino group location and chiral selectivity play an important role in sorption. Comparison of lysine and tyrosine sorption in different sediments indicates that source and diagenetic state of organic matter are important factors determining sorption capacity. Lysine sorbs much more to organic detritus from salt marsh sediment than to fresh Spartina root materials, marine particles, lignin or humic acids, indicating the importance of structural integrity in sorption. Desorption hysteresis of glutamic acid, putrescine and lysine (in dried sediment) suggests the presence of enzyme-type sorption sites of high sorption energy or multiple binding mechanisms. Taken together, these findings suggest that organic matter plays the major role in amino acid sorption in organic-rich sediments.     

气象部门电子政务探讨

一套电视天气预报节目的成功制作与播出，与节目的前期精心策划是密不可分的。本文通过对山西电视台公共频道天气预报节目的策划过程进行分析，旨在提高大家对节目策划重要性的认识和理解，同时提高电视气象节目的策划水平，更好地打造精品栏目。     

Sorption behavior of U(VI), ~(234)U(VI) and ~(238)U(VI) onto fracture-filling clays in Beishan granite, Gansu: Application to selecting the site of high-level radwaste repository in China

Knowing the transport of uranium and radionu-clides through the environment is important for as-sessing the risk posed by long-term disposal of rad-waste. Granitic rocks have been selected as a host-rock type for the first high-level radwaste repository in China. According to the Chinese High-level Rad-waste Management Program, high-level radwaste (HLW) will be buried at 800―1000 m depth in a granitic pluton in Northwest China and, specifically, in the A granitic complex of Beishan area,…     

Spectroscopic study of heavy metals sorption on clinoptilolite

Sorption of heavy metal cations (Pb(II), Cr(III), Cd(II), Ni(II)) from aqueous solutions on natural Na-clinoptilolite was studied using atomic absorption spectrometry (AAS) and FT-IR spectroscopy. It was found that the sorption capacity of clinoptilolite decreases in the following order: Pb(II) (22,600 mg/kg), Cr(III) (21,200 mg/kg), Cd(II) (10,400 mg/kg) and Ni(II) (6,200 mg/kg). In the FT-IR spectra of the samples, in the region of pseudolattice vibrations (500–800 cm^–1), systematic changes connected with the type of cation and its concentration in the initial solution were observed. The proportions of ion exchange and chemisorption in the whole process of sorption were also estimated. It was found that the amount of cations sorbed on clinoptilolite depended on the concentrations and pH of the solutions used as well as on the contact time of zeolite-solution system. After 120 min of the reaction, despite the metal type, 90–100% of the total amount of cations were immobilized.     

美、日、韩动漫产业发展经验及对我国的启示

目前,动漫产业已发展成庞大产业集群和消费市场,全球形成了美、日、韩三足鼎立的动漫市场格局。我国动漫产业方兴未艾,有关省市积极发展这一新兴产业,但产业规模小,产业链结构不合理,市场化运作不规范,专业人才短缺,明显落后于美、日、韩等国。本文基于我国比较优势,提出旨在发展和提升动漫产业竞争力的若干见解。首先是弘扬传统文化,塑造深入人心的动漫形象;其次,重视动漫产业链中上游产品的设计和原创,着力开发动漫产业链中相关的衍生产品,进一步优化产业链;第三,寻求适合本国动漫发展产业模式和创建和谐、良性的产业竞争内外部环境。     

Surface and adsorptive properties of wood char particles in soil

Char and soot （black carbon, BC） are highly surface-active materials that can play an important role in contaminant fate and bioavailability in soils and sediments. This report summarizes our research on the influence of adsorbate structure and BC properties on adsorption of organic compounds, and the possible attenuation of BC surface activity by humic substances in the environment. The BC was a maple wood char formed at 400 ℃ in air and under other conditions. The solutes were polar and apolar aromatic compounds. The following points will be discussed. （1） By comparing adsorption to nonporous graphite, it was shown that molecular sieving effects （steric restriction） in the char micropore system occur in the order of increasing substitution on the benzene ring and in the order of increasing fused ring size. （2） By accounting for hydrophobic and steric effects it was shown that aromatic rings substituted with strongly pi-electron-accepting functional groups, such as nitro, undergo pi-pi electron donor-acceptor （EDA） interactions with the pi-donor polyaromatic （graphene） surface of the char. The free energy of adsorption due to pi-pi EDA interactions correlated with the free energy of molecular complexation in chloroform with model compounds representing the graphene surface （napthalene, phenanthrene, pyrene）. （3） A series of chars were prepared of different polarity （O content） but similar surface area and pore size distribution by varying temperature and atmosphere. Single- and bi-solute experiments showed that polar interactions with surface O are not a significant driving force for adsorption of polar compounds. Rather, surface O attracts water molecule clusters that inhibit adsorption of both polar and nonpolar compounds by competition. （4） Aging of char particles in a soil-water suspension strongly reduced char SA and sorption of added benzene. Studies were conducted with dissolved humic （HA） acid, HA-char co-precipitates, Ala＋-HA-char co-flocculates, and soybean oil representing humic lipid components.     

Sorption properties of 1, 3, 5-trichlorobenznene on kerogen

Kerogen is an important organic matter fraction widely spread in soils and sediments. It plays a major role in the sorption and sequestration of hydrophobic organic contaminants （HOCs） such as trichlorobenzene （TCB）. It is known that kerogen is geochemically heterogeneous due to the differences in source materials and diagenesis history. We hypothesized that kerogen derived from different source materials and diagenetic history exhibits different sorption properties for TCB. We employed two different kerogen materials （coals） as the original materials and two series of kerogen for a given series with an identical source material but different alteration history were yielded through thermal treatment at temperature ranging from 200 to 500℃. The original and treated materials were characterized for their physicochemical properties. Sorption experiments were conducted with batch reactor systems using 1, 3, 5-TCB as the HOCs sorbates and the original and treated materials as the sorbents.