用比电导法研究活性炭的吸附特性

用比电导法研究两种活性炭自稀水溶液中吸附强电解质硫酸铬和硫酸铜的吸附平衡特性。结果表明,在本文的研究条件下,两种活性炭对硫酸铬和硫酸铜都有吸附作用。同时,活性炭吸附硫酸铜的吸附平衡特性可以用 Freundlich 方程式来描述。研究的结果对固体在溶液中的吸附基础理论以及处理工业废水具有一定的意义。     

Electrokinetic Removal of Petroleum Hydrocarbon from Residual Clayey Soil Following a Washing Process

This study investigates total petroleum hydrocarbon (TPH) removal from residual clayey soil, after a washing procedure, using an electrokinetic process. Eight electrokinetic experiments were carried out to investigate the characteristics of TPH removal. When 0.1 M MgSO₄ or 0.1 M NaOH was used as an electrolyte, the electric current rapidly increased within the first 100 or 200 h, respectively. A negatively charged soil surface resulted in a more negative zeta potential and greater electroosmotic flow toward the cathode. Therefore, the accumulated electroosmotic flow (EOF) when using 0.1 M NaOH as the anolyte‐purging solution was higher than when using 0.1 M MgSO₄. Although the energy consumption for the two purging solutions was similar, the efficiencies of TPH removal when 0.1 M MgSO₄ and 0.1 M NaOH with surfactant were used were 0 and 39%, respectively, because the electroosmotic flow rate increased with TPH removal efficiency. When 5% isopropyl alcohol (IPA) was used as a circulation solution, the electric current increased but the TPH removal was similar to that using water. In terms of energy consumption, the use of a surfactant‐enhanced electrokinetic process with NaOH as electrolyte was effective in removing TPHs from low‐permeability soil.     

UNIQUE ASPECTS OF MODELING IRRIGATI0N-INDUCED SOIL EROSION

llNTRODUCTIONIrrigationisimp0rtanttof00dpr0ducti0nthr0ughoutthew0rld.Irrigati0nisused0naboutl5theworld'scropland(KendalIandPimentel,l994)and5%ofthew0rld'sfoodproductionland,whichincludesrangelandandpermanentcr0pland(FAO,l998).However,irrigatedlandproducesmorethan30%ofthew0rld'sf0od(Tribe,1994),whichis2l/2timesasmuchperunitareacomparedt0n0n-irrigatedproducti0n(KendallandPimentel,1994).IntheUnitedStates,approximatelyl5theharvestedcr0plandisirrigated,butalmost40thet0talcr0pvalue…     

多组份电解质溶液热力学——活度系数和渗透系数与高次极限定律的关联

自1973年Pitzer电解质溶液理论问世以来,它在海洋学、地球科学、生物学乃至化工中获得了广泛的应用。本文介绍在实际应用中有重要意义的高次极限定律及与活度系数、渗透系数间的关联,它们是Pitzer理论发展的重要组成部份。     

NaCl在DMF和1,2-丙二醇混合溶剂中电导的研究

在283~308K温度范围内测定了NaCl在DMF和1,2-丙二醇混合溶剂中的电导率,根据公式求得NaCl的摩尔电导率值,应用Kohlrausch经验规则,使用Origin软件进行线性拟合,作图外推求得NaCl在DMF和1,2-丙二醇混合溶剂中的无限稀释摩尔电导率λ0值,并讨论了NaCl溶液的电导率、摩尔电导率、无限稀释摩尔电导率与温度和浓度的关系。     

Experimental measurements of the streaming potential and seismoelectric conversion in Berea sandstone

The streaming potential across a porous medium is induced by a fluid flow due to an electric double layer between a solid and a fluid. When an acoustic wave propagates through a porous medium, the wave pressure generates a relative movement between the solid and the fluid. The moving charge in the fluid induces an electric field and seismoelectric conversion. In order to investigate the streaming potential and the seismoelectric conversion in the same rock sample, we conduct measurements with Berea sandstone saturated by NaCl solutions with different conductivities. We measure the electric voltage (streaming potential) across a cylindrical sample in NaCl solutions with different conductivities and under different pressures to determine the DC coupling coefficients. We also measure the seismoelectric signals induced by acoustic waves with a Berea sandstone plate at different frequencies and solution conductivities. The pressures of the acoustic waves are calibrated with a standard hydrophone (Brüel & 8103) at different frequencies (15–120 kHz). We calculate the quantitative coupling coefficients of the seismoelectric conversion at DC and at high frequencies with samples saturated by solutions with different conductivities. When the Berea sandstone sample is saturated by the NaCl solution with 0.32 mS/m in conductivity, for example, the DC and seismoelectric coupling coefficients at 15 kHz are 0.024 μV/Pa and 0.019 μV/Pa, respectively. The seismoelectric coupling coefficient is an important and helpful parameter for designing a seismoelectric tool. More experimental measurements of seismoelectric coupling coefficients in the frequency range of 100 Hz to 15 kHz are needed in the future.     

锂离子二次电池电解质的研究动态

简要介绍了锂离子电池和其电解质的发展概况 ,并重点介绍了锂离子电池电解质的分类以及各自的性能特点 ,展望了锂离子电池电解质的发展前景。     

电导法测定HCl在水和异丙醇混合溶剂中的活度系数

应用电导法测定了HCl在水和异丙醇混合溶剂中的活度系数,讨论了电解质溶液活度系数与温度和浓度的关系。     

电解质水溶液的结构

本文叙述了盐湖中主要离子Ｌｉ＋、Ｎａ＋、Ｋ＋、Ｍｇ２＋、Ｃａ２＋、Ｃｌ－、ＳＯ＿４￣２－、ＮＯ＿３和纯水的结构，介绍了主要研究方法Ｘ射线衍射．分析了溶液结构研究历史和现状，对溶液结构研究的未来进行了展望．     

Effective Removal of Microorganisms and Biostimulants of Wastewater by the Application of Various Electrolytes

A variety of electrolytes FeCl₃, CaCl₂, CuSO₄, Al₂(SO₄)₃, and LaCl₃ was investigated for their efficiency in removing biostimulants (phosphorous and nitrogen) to improve the water quality. Results show that the removal of PO₄^3– was achieved below the detection limit (BDL) by two electrolytes, CuSO₄ and Al₂(SO₄)₃, and up to 1.0 ± 0.0 mg/L by LaCl₃ from a value of 15.0 mg/L, of the concentration of PO₄^3– in amended water. The turbidity was found to be removed significantly by FeCl₃, CuSO₄, and Al₂(SO₄)₃ by about 5.8 ± 2.6, 9.7 ± 1.0, and 5.4 ± 1.1 nephalometric turbidity unit (NTU), respectively. The removal of the members of Enterobacteriaceae viz., Escherichia coli, Enterobacter spp. Pseudomonas fluorescence, and Pseudomonas spp. was found almost in all the chemical precipitants but their removal was more significant in the water samples treated with CuSO₄, Al₂(SO₄)₃, and LaCl₃. To achieve a complete removal and to sustain the after effects of precipitation, such as recurrence of algal growth, the combination of CuSO₄ and Al₂(SO₄)₃ was investigated. Reduction in the turbidity from 30.83 to <2 NTU, phosphate ion from a value of 1.28 mg/L to BDL and ammonia ion from a value of 44.71 to 36.48 mg/L of natural pond water were observed after the treatment with CuSO₄ and Al₂(SO₄)₃ in combination.