不同钠吸附比含水介质中胶体迁移-沉积动力学          下载免费PDF全文

李海明  赵雪  马斌  李子琛  佟琪 《水文地质工程地质》2011,38(6):90-95

以滨海含水介质中天然胶体为研究对象,采用自行设计的室内土柱装置,研究不同钠吸附比胶体在滨海含水介质中迁移动态特征,测定了胶体沉积动力学曲线,计算了胶体总沉积率和沉积速率常数,最后对胶体迁移沉积机理进行了探讨。研究结果表明,胶体的穿透曲线与示踪离子相比,存在一个临界孔隙体积数(临界点),在临界点之前胶体的迁移速度大于示踪离子,之后则相反;胶体未发生完全穿透,钠吸附比SAR为0,2.85和∞;出水胶体最大相对浓度为0.65,0.16和0.70;胶体在含水介质迁移过程中发生了沉积,沉积量随孔隙体积数的增加而增加。胶体在含水介质中迁移的总沉积率分别为50.96%、87.95%和54.24%。钠吸附比SAR=2.85时沉积动态曲线为直线,沉积速率常数为0.151h-1,而钠吸附比SAR为0和∞时胶体沉积动态曲线为分段直线,拐点前后胶体沉积速率常数分别为0.072 h-1、0.048h-1和0.211 h-1、0.194 h-1。研究结果用双电子层理论可以很好地解释。  相似文献   

河北丰宁县洪汤寺温泉的水化学与同位素特征   总被引：2，自引：1，他引：1       下载免费PDF全文

张雪  周训  李再光  王莹  许庭武  郭小娟 《水文地质工程地质》2010,37(5):123-127

河北丰宁县的洪汤寺温泉出露于燕山期第四期的钾长花岗岩中,是由地下水接受大气降水入渗补给后向深处循环获得热量上升到地表后形成的。其TDS小于400mg/L,主要阳离子为Na+,主要阴离子为SO42-和HCO 3-,水化学类型属于SO4.HCO3—Na型水,特点为F-、偏硅酸以及氡含量高,分别为17.5mg/L、75.7mg/L和131.1 Bq/L。热水的同位素资料表明,洪汤寺温泉热水起源于大气降水,用氚法估算出的年龄在22a以上。利用地热温标估算地下热储温度范围为79～109℃。钻孔揭露后自流量增大,达11.6 L/s。  相似文献   

Seismic isolation analysis of FPS bearings in spatial lattice shell structures   总被引：2，自引：2，他引：0  

Kim Yong-Chul  Suduo Xue  Peng Zhuang  Wei Zhao  Chenghao Li 《地震工程与工程振动(英文版)》2010,9(1):93-102

<正>A theoretical model of a friction pendulum system(FPS) is introduced to examine its application for the seismic isolation of spatial lattice shell structures.An equation of motion of the lattice shell with FPS bearings is developed.Then, seismic isolation studies are performed for both double-layer and single-layer lattice shell structures under different seismic input and design parameters of the FPS.The influence of frictional coefficients and radius of the FPS on seismic performance are discussed.Based on the study,some suggestions for seismic isolation design of lattice shells with FPS bearings are given and conclusions are made which could be helpful in the application of FPS.  相似文献   

Removal of Ni(II) from Aqueous Solutions by Nanoscale Magnetite     

Xue Song Wang  Jun Jun Ren  Hai Jie Lu  Lei Zhu  Fei Liu  Qian Qian Zhang  Juan Xie 《洁净——土壤、空气、水》2010,38(12):1131-1136

Magnetite nanoparticles were applied to remove Ni(II) from aqueous solutions as a function of pH, contact time, supporting electrolyte concentration, and analytical initial Ni(II) concentration. The highly crystalline nature of the magnetite structure with diameter of around 10 nm was characterized with transmission electron microscopy (TEM) and X‐ray diffractometry (XRD). The surface area was determined to be 115.3 m²/g. Surface chemical properties of magnetite at 25°C in aqueous suspensions were investigated. The point of zero charge (pHzpc) was found to be 7.33 and the intrinsic acidity constants (${\rm p}K_{{\rm a}1}^{{\rm s}} $ and ${\rm p}K_{{\rm a}2}^{{\rm s}} $ ) were found to be 9.3 and 5.9, respectively. The surface functional groups were investigated with Fourier transform‐infrared spectroscopy (FTIR) as well. Batch experiments were carried out to determine the adsorption kinetics and mechanism of Ni(II) by these magnetite nanoparticles. The adsorption process was found to be pH dependent. In NaCl solutions, Ni(II) adsorption increased with increasing ionic strength while in NaClO₄ solutions, Ni(II) adsorption exhibited little dependence on the ionic strength of the solution. The adsorption process better followed the pseudo‐second order equation and Freundlich isotherm.  相似文献   

北京市大气PM2.5中多溴联苯醚污染水平与来源分析   总被引：1，自引：1，他引：0  

杨雪  刘大锰  孙俊玲 《现代地质》2010,24(2):355-361

2008年1月、9月和10月在北京城区5个采样点共采集9个大气颗粒物PM_2.5样品。遵循US EPA-1614方法,采用同位素稀释、高分辨气相色谱/高分辨质谱(HRGC/MS)联用技术,测定了大气颗粒物PM_2.5样品中14种多溴联苯醚(PBDEs)的质量浓度,研究了北京市城区大气颗粒物PM_2.5中多溴联苯醚的污染水平、分布特征及来源。结果表明: 9个大气颗粒物PM_2.5样品中PBDEs的质量浓度范围为2.82~57.94 pg/m³,平均值为15.67 pg/m³,BDE-209的质量浓度为0.34~7.32 pg/m³,PM_2.5样品中PBDEs的质量浓度冬季高于秋季;高溴代联苯醚在颗粒物中的含量高,低溴代联苯醚的含量低;交通源对大气颗粒物PM_2.5中PBDEs的污染贡献值很小,工业污染源贡献大于交通源,从含有溴代阻燃剂的物品释放到大气中的PBDEs对大气颗粒物PM_2.5中PBDEs的污染贡献值最大。  相似文献   

青海南部早二叠世火山-沉积背景的岩石地层序列   总被引：1，自引：0，他引：1  

牛志军  段其发  王建雄  何龙清  白云山 《地球科学》2010,35(1):11-21

研究区位于青海南部长江源区, 大地构造上属东特提斯构造域, 为金沙江结合带与澜沧江结合带间昌都地块的一部分.青海南部二叠系沉积类型复杂, 多呈断块(片)状出露, 尤其是受火山事件影响的下二叠统.关于下二叠统(乌拉尔统)的对比及地层划分目前仍存在较多争议, 认识的不同点主要集中于火山岩的层序归属、地质时代、区域对比等.以实测剖面为基础, 系统调查岩石地层的岩性组合、沉积环境等, 通过着重于各地层单位(尤其是火山岩系)的生物群研究, 重新厘定火山-沉积背景下的岩石地层序列.类动物群的研究表明诺日巴尕日保组和九十道班组在青海南部地区具穿时性.地层序列的建立表明青海南部早二叠世早期为较稳定的浅灰色中厚层状碳酸盐岩.罗甸期强烈的火山喷发, 形成了特殊火山-沉积地貌, 对沉积古地理格局形成明显的制约, 沉积相变快, 可划分为4种沉积类型, 形成同期异相的诺日巴尕日保组和尕笛考组.自祥播期之后, 主要为一套厚层状生物屑灰岩(九十道班组), 在青海南部分布较广, 代表火山活动暂时停止后的台地相沉积, 罗甸期复杂的古地理格局, 至此则构成相对统一的较稳定的浅水碳酸盐岩台地.   相似文献   

贵州青岩地区早-中三叠世生物地层     

陈晶  童金南  牛志军  周士钦  宋海军  易飞 《地球科学》2010,35(1):51-61

贵州青岩地区下-中三叠统发育齐全,化石丰富,尤其是中三叠世“青岩动物群”,具有生物辐射性质.为了研究二叠纪末生物大灭绝事件后的生物复苏及辐射过程,对该区下、中三叠统剖面进行了实测,并从沉积学、古生物学上进行了系统研究.识别出5个牙形石带:Neospathodus dieneri带、Neospathodus waageni带、Neospathodus pingdingshanensis带、Neospathodus homeri带、Chiosella timorensis带,建立2个有孔虫组合和6个双壳类组合.并根据牙形石化石初步确定出印度阶与奥伦尼克阶及奥伦尼克阶与安尼阶的界线.多门类化石的分布和生态组合结构表明,大灭绝后的复苏-辐射第一幕发生于安尼期早期,安尼期中期雷打坡页岩段的化石组合具有典型辐射后期的生态繁荣景象.古环境研究表明,本区从三叠纪初到中三叠世安尼期沉积水体总体上震荡式变浅,表现为盆地-陆棚-台缘斜坡-台地-盆地-台缘斜坡-陆棚的演变过程.   相似文献   

Feasibility of central loop TEM method for prospecting multilayer water-filled goaf     

Shu Yan  Gou-Qiang Xue  Wei-Zhong Qiu  Hai Li  Hua-Sen Zhong 《应用地球物理》2016,13(4):587-597

With deep mining of coal mines, prospecting multilayer water-filled goaf has become a new content that results from geophysical exploration in coalfields. The central loop transient electromagnetic (TEM) method is favorable for prospecting conductive layers because of the coupling relationship between its field structure and formation. However, the shielding effect of conductive overburden would not only require a longer observation time when prospecting the same depth but also weaken the anomalous response of underlying layers. Through direct time domain numerical simulation and horizontal layered earth forward modeling, this paper estimates the length of observation time required to prospect the target, and the distinguishable criterion of multilayer water-filled goaf is presented with observation error according to the effect of noise on observation data. The observed emf curves from Dazigou Coal Mine, Shanxi Province can distinguish multilayer water-filled goaf. In quantitative inversion interpretation of observed curves, using electric logging data as initial parameters restrains the equivalence caused by coal formation thin layers. The deduced three-layer and two-layer water-filled goafs are confirmed by the drilling hole. The result suggests that when observation time is long enough and with the anomalous situation of underlying layers being greater than the observation error, the use of the central loop TEM method to prospect a multilayer water-filled goaf is feasible.  相似文献   

Magnetotelluric study of the Xuefeng mountain area,Hu’nan Province,China          下载免费PDF全文

Musen Chen  Lingxiang Xue  Yousheng Wang  Shengjun Zhu 《地震科学（英文版）》2016,29(2):127-137

A magnetotelluric study was carried out in the Xuefeng mountain uplift belt and its western margins. A detailed investigation was made of the resistivity of the formations, and reliable data were obtained. The sedimentary cover and basement structure of the Xuefeng mountain area and the deep geological structure were analyzed in detail using magnetotelluric data from the two-dimensional inversion of the resistivity profile data in combination with regional gravity and magnetic data. It was concluded that the tectonic movements were characterized by basement detachment, and north-south ramp. The study area can be divided into a southern uplift zone, a southern thrust-faulted zone, a central uplift zone, and a northern depression zone. This work has provided geophysical evidence that can be used in future studies of the tectonics and petroleum geology of this region.  相似文献   

损伤破裂砂岩单轴蠕变特性试验研究     

牛双建  党元恒  冯文林  杨大方 《岩土力学》2016,37(5):1249-1258

深部岩体工程处于高应力环境中,开挖破裂后的工程岩体在持续的高地应力作用下具有很强的时间效应,深入研究其峰后蠕变特性,具有重要的理论和实际应用价值。先采用RMT-150B型岩石力学试验系统对完整岩样进行单轴峰前屈服、峰后破裂卸载试验,制备出具有不同破裂损伤程度的峰前屈服、峰后破裂的损伤岩样;再采用RLW-2000型微机伺服岩石三轴流变仪对其进行单轴蠕变试验,研究其单轴蠕变力学特性。研究结果表明：损伤岩样波速与完整岩样相比,均出现了不同程度的降低;损伤岩样各级应力水平下,瞬时应变量均是随着应力水平的增加而逐步增加,且均符合线性函数关系;相同应力水平下,峰后破裂损伤岩样瞬时应变明显大于峰前屈服损伤岩样;各级应力水平下,总体上各蠕变量随着应力水平的增加而逐步提高,且均符合指数函数关系;相同应力水平下,峰后破裂损伤岩样蠕变量明显大于峰前屈服损伤岩样,且随着荷载水平的进一步提高,两者差异程度增加;损伤岩样各瞬时变形模量随着应力水平的增加均逐步提高,两者之间符合线性函数关系;各应力水平下对应的瞬时变形模量存在明显差异,岩样损伤程度越高,瞬时变形模量越低;各损伤岩样在各级应力水平下,改进的西原模型能够较好地模拟其单轴蠕变特征。  相似文献