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1.
We discuss a strategy capable of a quantitative long-term monitoring of water saturation and volume variation of light non-aqueous phase liquids in the soil. The goal was reached monitoring a controlled sand cell contaminated with classical gasoline over 124 days, using geophysical methods such as electrical resistivity tomography, induced polarization and ground penetrating radar. We show that empirical relations, linking the water saturation to the physical parameters measured as resistivity from electrical resistivity tomography and travel time from georadar with advanced processing, are good tools for this purpose. The consistence of the proposed process is validated by both good overlap of results carried out from electrical resistivity tomography and georadar and theoretical models simulating the actual experiment. 相似文献
2.
I. Brandariz P. Castro M. Montes F. Penedo M.E. Sastre de Vicente 《Marine Chemistry》2006,102(3-4):291-299
Acid–base equilibrium constants of triethanolamine (TEA) have been determined by potentiometric titrations with a glass electrode, at 25 °C. Ionic strength was kept constant with only one electrolyte (using one of these salts: NaCl, KCl, MgCl2 or CaCl2), with binary mixtures of MgCl2 and CaCl2, and finally, in a solution with a composition approximately similar to that of natural seawater without sulfate. Equilibrium constants have been expressed in function of ionic strength by means of Pitzer equations and interaction parameters proposed in this theory have been obtained. It has been found that acid–base behaviour of TEA depends greatly on the salt used: basicity of TEA is decreased by CaCl2, while it is increased by the other electrolytes used in this work. 相似文献
3.
分析了表面活性剂和非水溶相有机污染物在水和土壤环境中的相互作用,以及表面活性的特性,解释了表面活性剂增效修复水和土壤环境中非水溶相污染物的机制。表面活性剂溶液通过增溶作用和增流作用,驱除地下水含水层中的非水相液体以及吸附于土壤颗粒物上的污染物,提高地下水和土壤中憎水性有机污染物的现场修复速率。增效修复效果依赖于临界胶束浓度(CMC)、污染物和表面活性剂的吸附特性、污染物的溶解性和土壤类型等。表面活性剂能增加化合物的溶解度,降低与水的界面张力,并形成乳液。 相似文献
4.
The combined measurement of dark matter interactions with different superheated liquids has recently been suggested as a cross-correlation technique in identifying WIMP candidates. We describe the fabrication of high concentration superheated droplet detectors based on the light nuclei liquids C3F8, C4F8, C4F10 and CCl2F2, and investigation of their irradiation response with respect to C2ClF5. The results are discussed in terms of the basic physics of superheated liquid response to particle interactions, as well as the necessary detector qualifications for application in dark matter search investigations. The possibility of heavier nuclei SDDs is explored using the light nuclei results as a basis, with CF3I provided as an example. 相似文献
5.
GAO Daolin LIU Mingming GUO Yafei YU Xiaoping WANG Shiqiang DENG Tianlong 《《地质学报》英文版》2014,88(Z1):315-316
正1 Introduction As the lightest metal with the unique properties of energy production and storage,lithium is regarded as the new century energy metal.Lithium and its compounds were widely used in various industrial fields,especially in 相似文献
6.
Frezzotti Maria Luce; Ferrando Simona; Dallai Luigi; Compagnoni Roberto 《Journal of Petrology》2007,48(6):1219-1241
Minerals, fluid inclusions and stable isotopes have been studiedin ultrahigh-pressure (UHP) OH-rich topazkyanite quartzitesfrom Hushan (west of Dongai), in southern Sulu (China). Thequartzites underwent a metamorphic evolution characterized bya peak stage (3·5 GPa and 730820°C) with theanhydrous assemblage coesite + kyanite I, followed by an earlynear-isothermal decompression stage (2·9 GPa and 705780°C)with growth of kyanite II, muscovite, and OH-rich topaz, andby decompression-cooling stages, represented by paragonite (1·9GPa and 700780°C) and pyrophyllite (0·3 GPaand 400°C) on kyanite (I and II) and OH-rich topaz, respectively.These rocks may exhibit unusually low 18O and D values acquiredbefore undergoing UHP metamorphism. Five distinct fluid generationsare recognized. Type I: concentrated peak solutions rich inSi, Al, and alkalis, present within multiphase inclusions inkyanite I. Type II: CaCl2-rich brines present during the growthof early retrograde OH-rich topaz. Type III, IV, and V: lateaqueous fluids of variable salinity, and rare CO2 present duringamphibolite- and late greenschist-facies conditions. A numberof conclusions may be drawn from these relationships that havean effect on fluid evolution in deeply subducted continentalrocks. (1) At a pressure of about 3·5 GPa alkalialumino-silicateaqueous solutions, with compositions intermediate between H2Ofluid and melt (H2O > 25 and 50 wt %) evolved from quartzites,probably generated by dehydration reactions. (2) During earlydecompression stages, at the transition from UHP to high-pressure(2·9 GPa) conditions, brines of external origin withhigher water contents (82 wt % H2O) initiated the growth ofOH-rich topaz and muscovite. (3) The subsequent decompression,at P <2 GPa, was defined by a limited circulation of NaClaqueous fluids, and CO2 infiltration. Overall, fluid inclusionsand stable isotopes highlight a metamorphic fluidrockinteraction characterized by internally derived intermediateaqueous solutions at UHP, followed by infiltration of Cl-richbrines with higher water activities. KEY WORDS: ultrahigh-pressure metamorphism; OH-rich topaz; fluid inclusions; stable isotopes; supercritical liquids 相似文献
7.
Migration characteristics of dense non-aqueous phase liquids (DNAPLs) in the subsurface can be expressed as a water–DNAPL two-phase system based on mainly the k–S–p relations, which describe the relations among relative permeability (k), degree of water saturation (S), and capillary pressure head (p). The aims of this research are to develop an experimental system with new type of probes, such as the electrical conductivity probe for measuring the degree of water saturation and the hydrophilic and hydrophobic tensiometer for measuring the pore water and DNAPL pressures, and also to estimate the results obtained from the developed experimental system. From these tests, the excellent k–S–p relations were obtained and the efficiency and validity of this developed experimental system have been confirmed in terms of the concept of the scaling coefficient calculated by interfacial tensions. 相似文献
8.
The densities of 36 water samples from the Huanghe River estuary and Bohai Bay were determinedby a magnetic float densimcter under three temperatures from 15℃ to 25℃.All the measured densities ofsamples were greater than that of the values calculated from the International Equation of State of Seawater.The differences between the measured and calculated densities increased with the decrease of salinities.The dif-ferences appeared exponentially correlated with[Ca~(2+)]/s,[Mg~(2+)]/s and[SO_4~(2-)]/s,and had"s"type curverelationship with the alkalinity in all salinity range.But in the salinity ranging from 25.72 to 31.57,therelationships were all linear.The density difference can be estimated from the equation △ρ(10~3kg·m~(-3))=(-2.79+236.5([Ca~(2+)]/s)/(-9.7464×10~(-3)+[Ca~(2+)]/s).It was the high alkalinity and[Ca~(2+)]/s that resulted in the measured densi-ties of seawaters being higher than the calculated densities in the Huanghe estuary and Bohai Bay. 相似文献
9.
以钛酸四丁酯(TEOS)、去离子水为原料,离子液体1-丁基-3-甲基四氟硼酸咪唑盐([Bmim]BF4)为表面活性剂,通过溶剂热法制备了锐钛矿相TiO2纳米颗粒。用X-射线衍射仪(XRD)、扫描电镜(SEM)、紫外-可见吸收光谱仪(UV-Vis)对产物的晶相、形貌和光学性能进行表征。为了评估光催化活性,并以甲基橙水溶液为研究对象,在紫外光照射下分析不同照射时间下光降解效率。结果表明,离子液体、去离子水和钛酸四丁酯的体积比为1.3∶1∶1.3时,反应所得到的TiO2具有较高光催化活性,明显优于未添加离子液体的产品,这一结果可归因于其具有较大的比表面积。 相似文献
10.