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多环芳烃室内土柱淋溶行为的CDE模型模拟  [PDF]
胡俊栋,陈静,王学军,叶友斌,沈琼,陶澍
环境科学学报 , 2005,
Abstract: 采用土柱淋溶实验方法对多环芳烃(PAHs)在人工污染土柱中表面活性剂淋溶下的运移进行了实验室研究,获得了示踪剂Br-和PAHs的穿透曲线(BTCs);并通过室内批量平衡试验(PAHs和表面活性剂吸附试验和表面活性剂对PAHs吸附解吸影响试验)获得了吸附系数,进而获得阻滞因子.基于这些实验室结果,通过CXTFIT2.1软件,用平衡CDE模型拟合了Br-的BTCs,获得物理和水动力参数;并在此基础上应用CDE非平衡模型拟合PAHs在表面活性剂淋溶条件下土柱中的BTCs以及不同时刻、不同埋深处PAHs浓度的动态变化,预测了PAHs在土柱中的迁移趋势.
Influences of Surfactant on the Transport of PAHs in Artificially Contaminated Soil Columns
表面活性剂对人工污染土壤装填土柱中PAHs迁移渗透的影响

CHEN Jing,WANG Xue-jun,HU Jun-dong,TAO Shu,LIU Wen-xin,
陈静
,王学军,胡俊栋,陶澍,刘文新

环境科学 , 2005,
Abstract: The effect of anionic surfactant LAS on leaching of PAHs from artificially contaminated soil was studied. The interaction of these processes were studied in a two-layer column experiment with a base layer of uncontaminated soil(9cm) and a top layer of artificially contaminated soil(1cm). Results show that 5 critical micelle concentration (CMC) LAS enhanced the transport of PAHs. The breakthrough curves of low ring PAHs followed the normal distribution and the relative leaching ratios of 4 or more rings PAHs were low, and not more than 10%. The transport of PAHs was retarded compared with LAS, and the high ring PAHs were retarded more significantly. Linear correlation was observed between the relative leachability of the individual PAHs and the octanol/water coefficient of PAHs.
Study on effect of humic acid on the leaching and intercepting of polycyclic aromatic hydrocarbons(PAHs) in contaminated soil
腐植酸对多环芳烃在污染土壤中淋出及截留分解的效果研究

Yu Hongyan,Chen Xiaofang,
于红艳
,陈晓芳

环境工程学报 , 2010,
Abstract: 多环芳烃是固废拆解地一类污染较严重的有毒有机物质,用腐植酸作表面活性剂淋洗污染土壤起到较好的增溶及截留分解污染物的作用,达到修复污染土壤的目的。实验结果表明,随着腐植酸加入量的增加,菲、萘、荧蒽、芘和∑PAHs的淋出量显著提高,在污染红壤中最大淋出率分别为52.9%、70.1%、30.5%、46.1%和42.8%,在污染水稻土中最大淋出率分别为51.8%、67.3%、35.0%、38.3%和35.5%,同时多环芳烃的截留分解率也相对较高,而污染红壤和水稻土的总修复率分别达到56.3%和49.8%。
Kac-Moody algebras and the cde-triangle  [PDF]
Torsten Ekedahl
Mathematics , 2004,
Abstract: This is the written version of a talk at the conference on ``Non-commutative geometry and representation theory in mathematical physics'' held in Karlstad, Sweden, 5--10 July, 2004. In it we show that the duality formula of Rocha-Caridi and Wallach is a simple consequence of the so called cde-triangle of modular representation theory. It tries to reflect the attempt of the talk to cater to the differing backgrounds of its listeners.
表面活性剂对采油区土壤装填土柱中PAHs迁移渗透的影响  [PDF]
陈静,胡俊栋,王学军,陶澍,刘文新
环境化学 , 2015,
Abstract: 以阴离子表面活性剂十二烷基苯磺酸钠(LAS)对采油区土壤(MGP)中PAHs的淋洗效果进行研究.结果表明,5CMC(临界胶束浓度)LAS促进了土柱中PAHs的迁移渗透,土柱中PAHs的淋溶率较低,而且仅土柱上层5cm的土样中PAHs发生了较为明显的淋溶.与Br-离子穿透曲线相比,土柱中PAHs的淋溶均有滞后现象,而且随着环数的增加,PAHs的淋溶滞后现象愈加明显.PAHs的迁移渗滤性与其辛醇/水分配系数之间具有显著负相关性,说明随着辛醇/水分配系数的增加,PAHs的淋溶率逐渐降低.
表面活性剂对人工污染土壤装填土柱中PAHs迁移渗透的影响  [PDF]
陈静,王学军,胡俊栋,陶澍,刘文新
环境科学 , 2005,
Abstract: 研究了阴离子表面活性剂十二烷基苯磺酸钠(LAS)对人工污染土壤中多环芳烃(PAHs)的淋洗效果,土柱分为2层,上层为人工污染PAHs的土壤(1cm),下层为清洁土壤(9cm).实验结果表明,5CMC(临界胶束浓度)LAS促进了土柱中PAHs的迁移渗透.低环PAHs的穿透曲线基本符合正态分布,4环以上PAHs相对淋溶率较低,低于10%.与表面活性剂溶液穿透曲线相比,PAHs的淋溶均有滞后现象,而且随着环数的增加,PAHs淋溶滞后现象越加明显.分析人工污染土柱中PAHs的相对淋溶率与其辛醇水分配系数的关系,发现两者之间有显著负相关性.
煤矸石堆积下多环芳烃的淋溶污染特征  [PDF]
王新伟,钟宁宁,韩习运
环境工程学报 , 2013,
Abstract: 淋溶是使有害物质析出的主要途径之一。为查明煤矸石堆放淋溶造成的有机污染效应,对不同风化强度煤矸石进行了动态淋溶模拟实验,系统研究了煤矸石中USEPA优先控制的16种多环芳烃(PAH16)的析出规律和迁移方式。获得煤矸石中多环芳烃(PAHs)淋溶特征如下:煤矸石堆积期遭受短期降雨(500~1600mm)作用后,煤矸石溶出的PAH16总质量浓度达125.6~451.2ng/L。PAH16溶出量初期较高,在一定降雨期后又达到峰值,酸雨条件下,煤矸石山淋溶出的PAH16可由线性累加转为指数快速累加的趋势。淋溶液中优势组分为萘、二氢苊、芴和菲,4种组分之和占所测PAHs总量的80%~90%。煤矸石溶出的PAHs环数分布为2环>3环>4环>5环、6环。迁移方式上,2环PAHs多以溶解相迁移,3环PAHs主要以颗粒态迁移,存在少量溶解形式,而4环以上PAHs则以颗粒相形式迁移。
Identification and functional analysis of a CDE/CHR element in the POLD1 promoter
NanMeng Song,XiaoYu Zhu,Lei Shi,Jing An,YanWei Wu,JianLi Sang
Science China Life Sciences , 2009, DOI: 10.1007/s11427-009-0077-5
Abstract: DNA polymerase delta is encoded by the POLD1 gene, the transcription of which is strictly cell cycle-dependent. However, the means by which POLD1 transcription is regulated by the cell cycle mechanism is currently unknown. We discovered a novel element in the POLD1 promoter known as a CDE(cell cycle-dependent element)/CHR(cell cycle gene homology region) element. A series of luciferase reporter constructs containing various POLD1 promoter mutations were used to investigate the role of the CDE/CHR element in POLD1 transcription. When the CDE/CHR element was mutated, the promoter activity was up-regulated, and the cell-cycle related factors E2F1 and p21 stopped regulating the promoter. Furthermore, cell cycle-dependent changes in the promoter activity required the integrative CDE/CHR element. Electrophoretic mobility shift assay (EMSA) revealed the presence of at least three types of DNA/protein complexes binding to the CDE/CHR element. Our findings provide strong evidence that the CDE/CHR-like sequence is an active functional element in the POLD1 promoter, which is important for the cell cycle regulation of the POLD1 gene.
土壤胶体在不同饱和度土壤介质中的释放与淋溶行为研究  [PDF]
农业环境科学学报 , 2009,
Abstract: 采用饱和与非饱和填充土柱纵向淋溶研究方法,结合对流弥散模型方程(CDE)对穿透曲线的拟合计算,全面考察了土壤介质水饱和度、土壤水pH/离子强度、土壤孔隙水流速和土壤胶体颗粒大小对天然土壤胶体在实际土壤介质中释放、沉积迁移行为的影响。分别获取胶体扩散系数和阻滞因子值,定量说明实验中水化学、水动力学等条件的作用影响力。结果显示,介质不饱和条件不利于胶体的释放和淋溶;高pH和低离子强度条件对土壤胶体释放与迁移有利;淋溶过程的间断干扰,可以促使土壤胶体的增量淋溶释放;淋溶强度及胶体颗粒粒径大小,能够影响胶体穿透时间和穿透浓度峰值大小。
稳定流场饱和均质土壤中农药淋溶动态预报模式的探讨  [PDF]
任理,毛萌,张仁铎
环境科学学报 , 2003,
Abstract: 基于对流弥散方程(CDE)的解和传递函数模型(TFM)中呈对数正态分布的溶质迁移时间的概率密度函数,构造了稳定流场饱和砂质壤土中仅考虑吸附作用时农药淋溶动态的预报模式.建立该模式的思路首先是利用示踪剂的穿透曲线,由CDE的解析解反求水动力弥散系数;再针对不同的阻滞因子通过求解CDE正问题的数学实验,生成农药穿透曲线的模拟值.接着应用对数正态概率密度函数拟合得到相应于不同阻滞因子的农药迁移时间的均值和方差.结果表明:均值与阻滞因子为乘幂函数的关系,而方差随阻滞因子的变化甚小,且不同流速下农药迁移时间的均值与方差随阻滞因子的变化亦呈现相同的规律.通过农药阿特拉津的淋溶实验对该模式的预报精度进行了检验.
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