Geochemical process of fluorine in soil     

Xiaojing Liu  Binbin Wang  Baoshan Zheng 《中国地球化学学报》2014,33(3):277-279

Fluorine is in the dynamic balance of two geochemical processes, enrichment and leaching, reflecting the adsorption and desorption of fluoride by clay minerals, respectively. The two geochemical processes of fluorine in soil are influenced by factors including geochemical characteristics of soil and clay minerals, pH and sanity of soil solutions, climate, grazing and agriculture activities. Main factors controlling enrichment and leaching process of fluorine in soil can be found with interaction consideration.  相似文献   

Preparation of Silver Nanoparticles Film and the Adsorption of Iodide     

GAO Can  HU Yaoqiang  ZHANG Huifang  YE Xiushen  LI Quan  LIU Haining  WU Zhijian 《《地质学报》英文版》2014,88(Z1):313-314

正Iodine and iodine compounds are widely applied in medicaments,dyes,energy materials,food additives etc.The development and utilization of iodine resources have attracted much attention.A large amount of iodide is  相似文献   

A REVIEW OF HEAVY METAL ADSORPTION BY MARINE ALGAE     

潘进芬  林荣根  马丽 《中国海洋湖沼学报》2000,18(3):260-264

ＩＮＴＲＯＤＵＣＴＩＯＮＴｈｅｔｏｘｉｃｉｔｙｏｆｈｅａｖｙｍｅｔａｌｓｒｅｌｅａｓｅｄｉｎｔｏｔｈｅｅｎｖｉｒｏｎｍｅｎｔｈａｓｒｅｃｅｎｔｌｙｔｒｉｇｇｅｒｅｄａｎｕｍｂｅｒｏｆｓｔｕｄｉｅｓａｉｍｉｎｇａｔｔｈｅｒｅｍｏｖａｌｏｆｍｅｔａｌｉｏｎｓｆｒｏｍａｑｕｅｏｕｓｓｏｌｕｔｉｏｎｓ (ＦｏｕｒｅｓｔａｎｄＶｏｌｅｓｋｙ ,1 997;ＦｅｈｒｍａｎｎａｎｄＰｏｈｌ,1 993 ;ＫｕｙｕｃａｋａｎｄＶｏｌｅｓｋｙ,1 989) .Ｉｔｗａｓｆｏｕｎｄｔｈａｔｔｈｅａｃｃｕｍｕｌａｔｉｏｎｏｆｈｅａｖｙｍｅｔａ…  相似文献   

Parameters affect foaming and foam stability during foam drilling     

Hazaea Mohammed  Youhong SUN  Ould El Houssein Yarbana 《世界地质(英文版)》2007,10(2)

The authors presented indoor practice experiments of parameters affect on foaming and foam stability. Experiments were carried out and special equipments were used to determine foaming and foam stability; tests were tabulated and charted. The effects of chemical and physical parameters on foaming and foam stability have been conducted.  相似文献   

EFFECTS OF COMPOSITION AND STRUCTURE OF ALGINATES ON ADSORPTION OF DIVALENT METALS     

郑乃余  张燕霞  范晓  韩丽君 《中国海洋湖沼学报》1994,(1)

Results of a series of experiments(on the adsorption of divalent metal ions by dried alginic acid, Na and Ca alginates of different composition and block structure) conducted in this systematic study of the effects of the composition and structure of alginates on the static adsorption equilibrium of divalent metal ions indicate that the properties of alginate adsorption to divalent metal ions are highly different, depending not only on the cations used, but also on the form and structure of the alginates. There is close correlation between the adsorption properties and the structure of the alginates. The selectivity coefficient of Na alginate for Cd-Sr ion exchange tends to increase with the increase of the M/G ratio in alginate, whereas the adsorption capacity of Ca alginate for Cu~(2+) ion decrease with the increase of the G-block or the average length of the G-block ((?)_G) and the total adsorption capacity of alginic acid is found to vary in the same order as the F_(MM)(diad frequency) in alginate in  相似文献   

Biodegradation and transport of benzene,toluene, and xylenes in a simulated aquifer: comparison of modelled and experimental results     

Jiin‐Shuh Jean  Ching‐Lang Tsai  Shen‐Haw Ju  Chun‐Wen Tsao  Shih‐Ming Wang 《水文研究》2002,16(16):3151-3168

Both laboratory experiments and numerical modelling were conducted to study the biodegradation and transport of benzene–toluene–xylenes (BTX) in a simulated semi‐confined aquifer. The factors incorporated into the numerical model include advection, hydrodynamic dispersion, adsorption, and biodegradation. The various physico‐chemical parameters required by the numerical model were measured experimentally. In the experimental portion of the study, BTX compounds were introduced into the aquifer sand. After the contaminants had been transported through the system, BTX concentrations were measured at 12 equally spaced wells. Subsequently, microorganisms obtained from the activated sludge of a sewage treatment plant and cultured in BTX mixtures were introduced into the aquifer through the 12 sampling wells. The distribution data for BTX adsorption by the aquifer sand form a nonlinear isotherm. The degree of adsorption by the sand varies, depending on the composition of the solute. The degradation time, measured from the time since the bacteria were added to the aquifer until a specific contaminant was no longer detectable, was 35–42 h for BTX. The dissolved oxygen, after degradation by BTX compounds and bacteria, was consumed by about 40–60% in the entire simulated aquifer; thus the aerobic conditions were maintained. This study provides insights for the biodegradation and transport of BTX in aquifers by numerical modelling and laboratory experiments. Experimental and numerical comparisons indicate that the results by Monod degradation kinetics are more accurate than those by the first‐order degradation kinetics. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   

无砟轨道聚氨酯碎石防水联结层单元模型试验研究     

谢康  苏谦  陈晓斌  刘宝  王武斌  王迅  邓志兴 《岩土力学》2023,(8):2308-2317

基于无砟轨道基床表层水力损伤病害产生机制,提出一种在基床表层上设置聚氨酯碎石防水联结层的水力损伤控制措施。通过建立级配碎石组(J-0)、透水型聚氨酯碎石组(J-5)及致密型聚氨酯碎石组(J-10)3组试验模型,研究聚氨酯碎石防水联结层的静动力特性、疲劳特性与防水特性。结果表明：静力加卸载作用下,J-10残余应变为2.6×10–6,最大位移约为1.0 mm,与下部基床表层级配碎石层变形适应性良好,耗能效果明显,在列车动力荷载水平作用下,可减小基床表层动变形与动应力幅值,增大动应力扩散范围;在长期动力循环荷载作用下,J-0与J-5在注水后结构层动力响应显著增大,而J-10动力响应在加载次数1～2万次后基本保持稳定;试验过程中J-10能够有效防止水分进入基床表层级配碎石层,而J-0与J-5水分不断下渗,引起级配碎石细颗粒损失。研究成果对整治多雨地区无砟轨道基床表层水力损伤病害具有重要的应用价值。  相似文献   

载炭泡塑吸附-电感耦合等离子体发射光谱法测定金矿石的金量   总被引：1，自引：1，他引：0  

陈景伟  李玉明  宋双喜  宋江涛  初琳 《岩矿测试》2015,34(3):314-318

载炭泡塑吸附法对金有良好的吸附性能,但只能用于抽滤吸附不能振荡吸附,分析手续繁杂。本文以载炭泡塑振荡吸附-电感耦合等离子体发射光谱法测定金矿石的金量。样品在650℃高温灼烧2 h,用50%王水和10%氯化铁加热溶解,溶液冷却后加入5%高锰酸钾氧化,用中密度规格的载炭泡塑两次振荡吸附溶液中的金,然后于580℃高温灼烧后以50%王水溶解灰分,直接用ICP-OES测定金量。方法检出限(3σ)为0.002μg/g,精密度(RSD,n=11)小于3.7%。本方法对金的吸附率大于99.9%,测定范围为0.01~90μg/g,对不同类型金矿石的适应性强,解决了以往泡塑吸附法吸附率较低、标准系列与样品需同时预处理的问题,对低含量和高含量样品均有较高的准确度。  相似文献   

页岩孔隙度测量实验方法分析与评价   总被引：2，自引：1，他引：1  

杨巍  薛莲花  唐俊  吕成福  徐勇  杨爽  陈国俊 《沉积学报》2015,33(6):1258-1264

页岩气是目前国内外非常规油气领域研究的热点,有效的页岩孔隙度值是评价页岩储层物性的重要参数。由于页岩本身具有易碎的特点,导致钻取柱体样品难度大,很多学者采用碎样法计算孔隙度,但碎样法与柱体法的差别及测定结果的有效性并未见相关研究成果。本文对相同样品通过三种不同方法:氦气膨胀法测孔隙度(柱体),真、视密度法及低温氮气吸附实验法(样品粉碎至40~60目)分别计算孔隙度。结果发现三种方法测定的三组孔隙度数值不同,每种方法在样品制备上及实验方法的差别是影响实验结果的主要因素,为检验三组孔隙度值的有效性,采用数理统计中的单因素方差分析法进行分析,结果表明页岩柱体与粉碎至40~60目范围内的页岩样品测量的孔隙度值虽有差别,但在有效范围内,具有一致性。但是将页岩粉碎后,页岩中的有效孔隙变化程度较大,故用柱体测定的有效孔隙度法优于其他两种碎样方法。  相似文献   

空气（泡沫）潜孔锤钻进工艺在王家岭煤矿紧急避险孔中的应用          下载免费PDF全文

赵福森  谭家政  杨晨  张凯 《探矿工程》2015,42(8):25-29

空气（泡沫）潜孔锤钻进工艺在王家岭煤矿紧急避险孔钻进中,有效解决了钻孔垂直度要求高、地层漏失等施工难点,实现了高质量快速成孔。该工艺平均机械钻速高达7.99 m/h,终孔水平位移仅为0.48 m,二开孔段每米综合成本504.8元。邻孔SW1水文补勘孔以泥浆作为循环介质、采用牙轮回转正循环钻进工艺,平均机械钻速为0.86 m/h,二开孔段每米综合成本为820.5元。前者平均机械钻速约是后者的9倍,较后者节约成本38.5%。与邻孔泥浆正循环牙轮回转钻进工艺相比,该工艺不仅解决了紧急避险孔施工难点,还提高了孔身质量、节约了工期、降低了成本,达到降本增效的目的,值得类似工程借鉴。  相似文献