垃圾场渗滤液中十二烷基硫酸钠的光度测定

三峡库区令人担忧的严重问题之一是城市生活垃圾填埋场渗滤液的迁移污染.渗滤液成分复杂,水质变化大,色度深、有恶臭.高浓度有机废水会污染地表水和地下水,破坏原有水体的用途,甚至危及原有的生态系统,若不妥善处理渗滤液,有害成分发生迁移转化,就会带来严重的二次污染,对库区环境构成严重危胁.     

双水相萃取法分离铍(Ⅱ)、铁(Ⅲ)与铁(Ⅱ)、铬(Ⅲ)、锰(Ⅱ)、铝(Ⅲ)

研究了在聚乙二醇2000(PEG)-硫酸钠(Na2SO4)-邻苯二酚紫(PV)体系中铍(Ⅱ)、铁(Ⅲ)、铁(Ⅱ)、铝(Ⅲ)、铬(Ⅲ)、锰(Ⅱ)的萃取行为。试验结果表明,铍(Ⅱ)在pH 3.5-7.0及铁(Ⅲ)在pH 4.0-7.0范围内可以被PEG相几乎完全萃取,而铝(Ⅲ)、铬(Ⅲ)在pH 1.0-7.0、锰(Ⅱ)在pH 1.0-4.5、铁(Ⅱ)在pH 1.0-4.5则不被萃取。从而实现了将铍(Ⅱ)(pH 3.5)、铁(Ⅲ)(pH 5.0)与铝(Ⅲ)、铬(Ⅲ)、锰(Ⅱ)、铁(Ⅱ)混合离子的定量分离。同时探讨了PEG相的萃取机理。     

Synthesis of new colloidal formations during the strengthening of different activated hydrated metallurgical slags

This paper reports on a comparison of experimental researches on the hydration hardening of different types of dumped ferrous slag (DFS) (blast furnace, open hearth, electric steel and converter), non-activated and activated with small (2%) additions of Portland cement or lime. Activation was found to accelerate the strengthening processes in the early stages of hydration resulting from the growth of colloidal sol–gel new formations in a more alkaline environment. Over time, these formations became denser and transformed into stone-like amorphous materials with a uniaxial strength of up to 47.6 MPa at 1 year of age. All these types of slag can, therefore, be used in different applications, for example, like traditional binders, such as Portland cement, to different ceramic goods, new construction materials, etc. But till now the results of this research were used only for the preparing of binder materials for natural soils strengthening as road bases in Russia. Highways whose roadbeds were built with these DFS as binder materials have shown excellent performance indices in different parts of Russia, including Siberia and northern regions.     

硅灰石矿物发光原料中Fe2+的去除与CaSiO3∶Eu3+的光谱特性

提出了用草酸．邻菲哕啉去除硅灰石中Fe^2 的方法，研究了浸取剂的浓度、浸取时间和温度等条件对Fe^2 的去除率的影响，在最佳的浸取条件下，Fe^2 的去除率达到98．35％。在去除猝灭剂后的硅灰石矿物中，掺加适量的稀土激活剂Eu^3 ，通过高温固相法制成荧光发光材料，发光强度明显提高，接近于化学试剂合成的发光材料。     

钯-8-羟基喹啉-5-磺酸络合物电极反应和十二烷基硫酸钠的增敏机理

钯 8 羟基喹啉 5 磺酸形成的络合物的峰电流 (pH 8.6 ,- 0 .6 8V)具有吸附特性 ,为不可逆电极反应过程。其电子转移数 (n)、电子转移系数 (α)及饱和吸附量 (Γs)分别为 2、0 .4 6和 2 .2× 10 - 9mol cm2 ;钯 与8 羟基喹啉 5 磺酸的络合比为 1∶2 ;稳定常数 (K)为 8.73× 10 7。加入阴离子表面活性剂十二烷基硫酸钠未形成三元络合物 ,催化电流是由与十二烷基硫酸钠共吸附在电极表面上的超氧阴离子自由基氧化了络合物的电极反应中间体所产生的。     

胶束增敏荧光光谱法测定吡哌酸

采用不同表面活性剂对吡哌酸在胶束体系中的荧光性质进行了研究，发现在酸性介质中十二烷基硫酸钠(SDS)对吡哌酸有较强的增敏作用，据此建立了胶束增敏荧光光谱法测定吡哌酸的新方法。方法线性范围为0．07-0．36μg／mL，检出限为0.04μg／mL，平均回收率为98．6％-101．3％，相对标准偏差为1．1％-1．2％。样品测定结果令人满意。     

Activity coefficients of electrolytes from the E.M.F. of liquid membrane cells. II - multicharged electrolyte solutions

The activity coefficients of Co(en)₃Cl₃ and K₂SO₄ were measured by means of a cell with ion-exchange liquid membranes following the method described in paper I. The results prove that this method is even more valuable with multicharged salts than with 1-1 electrolytes. The values obtained are precise and reliable down to dilution limits never before accessible, e.g., 4×10^–5 mol-kg^–1 in Co(en)₃Cl₃. High dilution levels are of particular importance when dealing with highly charged electrolytes since the trend at higher concentrations often leads to errors both in extrapolation to infinite dilution and in the absolute activity coefficients. As an application, the activity coefficients of [Co(en)₃]₂(SO₄)₃-suspected to be wrongly evaluated in past literature-were measured, and their values at low concentrations were actually lower than those quoted before.     

Chemical bond in alkali metal sulfates

In the context of the density functional theory of the local electron density the valence and differential density distribution in crystalline sulfates of M₂SO₄ (M is Li, Rb, and Cs) and double sulfates of MLiSO₄ were calculated using the pseudopotential method in the basis set of numerical atomic pseudo-orbitals. It is shown that in lithium sulfate crystallographically inequivalent oxygen atoms are in different charge states and have a different force of chemical bonding with sulfur. Anions are bonded to each other through lithium atoms that form tetrahedral complexes with oxygen. In rubidium sulfates the electron clouds of the anions overlap and chain structures form. Chemical bonding between the anion and the cation has an ionic nature. These features of the electron structure manifest themselves in double sulfates, where LiO₄ complexes that link the anionic chains also form, and heavy metals serve as cations.     

Effect of sodium dodecyl sulfate on lipase ofCandida lipolytica

The effects of sodium dodecyl sulfate on extracellular lipase produced byCandida lipolytica have been studied. The microorganism was grown in culture medium containing different sodium dodecyl sulfate concentrations added to the culture at different intervals of growth. The extracellular lipase activity was not detected when the treated culture supernatants were directly tested in Yeast Mold Agar-Triolein-Rhodamine plates, regardless of surfactant addition time and concentrations. However, after ammonium sulfate precipitation and dialysis, the extracellular lipase activity could be recovered. Therefore, the surfactant, under the experimental conditions used here, does not seem to be able to inhibit lipase production, but it does inhibit the enzyme activity because of its presence in the mixture of the reaction.     

Electrosorption of sodium cellulose sulfates with different substitution patterns

Various types of sodium cellulose sulfate (SCS), dissolved in a 1M LiCl solution, were investigated by alternating current (AC)polarography. The SCS samples differed in the degree of substitution (DS), thedistribution of substituents within the anhydroglucose unit (AGU), and alongthechain, due to the method of synthesis. The goal was to study theelectrosorptionbehavior, characterized by the shape of the desorption wave in the polarogram,as a function of the chemical structure of the SCS samples. The shape of thedesorption wave reflects domains of different substitution. A superimpositionofparameters like DS and pattern of substitution on the electrosorption behaviorwas observed. The AC polarography method described can be used as a tool todistinguish between an even or uneven distribution of substituents along thecellulose chain.