Electrochemical assessment of water|ionic liquid biphasic systems towards cesium extraction from nuclear waste

A room temperature ionic liquid (IL) composed of a quaternary alkylphosphonium (trihexyltetradecylphosphonium, P₆₆₆₁₄⁺) and tetrakis(pentafluorophenyl)borate anion (TB⁻) was employed within a water|P₆₆₆₁₄TB (w|P₆₆₆₁₄TB or w|IL) biphasic system to evaluate cesium ion extraction in comparison to that with a traditional water|organic solvent (w|o) combination. ¹³⁷Cs is a major contributor to the radioactivity of spent nuclear fuel as it leaves the reactor, and its extraction efficiency is therefore of considerable importance. The extraction was facilitated by the ligand octyl(phenyl)-N,N′-diisobutylcarbamoylphosphine oxide (CMPO) used in TRans-Uranium EXtraction processes and investigated through well established liquid|liquid electrochemistry. This study gave access to the metal ion to ligand (1:n) stoichiometry and overall complexation constant, β, of the interfacial complexation reaction which were determined to be 1:3 and 1.6 × 10¹¹ at the w|P₆₆₆₁₄TB interface while the study at w|o elicited an n equal to 1 with β equal to 86.5. Through a straightforward relationship, these complexation constant values were converted to distribution coefficients, δ_α, with the ligand concentrations studied for comparison to other studies present in the literature; the w|o and w|IL systems gave δ_α of 2 and 8.2 × 10⁷, respectively, indicating a higher overall extraction efficiency for the latter. For the w|o system, the metal ion-ligand stoichiometries were confirmed through isotopic distribution analysis of mass spectra obtained by the direct injection of an emulsified water–organic solvent mixture into an electron spray ionization mass spectrometer.     

2008奥运会秦皇岛赛区（足球）转播系统设置

本文主要介绍广东电视台高清转播车参与北京奥运会足球比赛秦皇岛赛区国际公共信号制作的视音频系统的路由、时钟同步系统.字幕系统、应急系统、音频系统、电源系统等,详细介绍了为做好这次奥运转播所做的一些特殊的设置.     

Determining the content and 13C abundance of total dissolved carbon in water samples by TOC analyser-mass spectrometer coupling

A combined system consisting of a TOC analyser connected to a quadrupole MS was recently described as a way of measuring the N content and the ¹⁵N abundance of total dissolved nitrogen in aqueous samples. This work examines whether this combination of instruments can also be used for the ¹³C determination of the total dissolved carbon in aqueous samples. A level of precision good for ¹³C-enriched samples was achieved with a relative standard deviation of <3%. By using an isotope ratio MS instead of the quadrupole MS employed here, TOC-MS coupling also ought to be suitable for determining natural ¹³C abundances.     

体育赛事转播系统及业务承载的初步思考

简要介绍了体育赛事转播系统的系统架构以及场馆电视转播设施的主要组成部分以及转播对网络的主要技术指标要求,并针对体育赛事转播业务的主要承载技术进行了分析,并希望能为后续的类似活动提供借鉴。     

扩展三值纠一检二码原理与设计

本文在三值汉明码一位检错纠错研究工作的基础上,对三值汉明码的检错纠错方法进行进一步研究.给出了扩展三值汉明码的形式,通过对扩展三值汉明码的错误分析获得了一位纠错和二位检错原理,给出了扩展三值汉明码的纠错码表,根据纠错码表提出了一位纠错方法,给出了基于三值光学计算机的扩展三值汉明码检错纠错概念结构图和功能部件,为检错纠错系统的光学设计提供一种途径.     

菜园土壤中的铜及其与土壤有机碳的关系

通过野外调查与室内分析相结合的方法研究了杭州市郊主要菜园土壤中铜的状况,并对其与土壤有机碳的关系作了探讨.取样分析结果表明,调查区域菜园土壤全铜含量在4.3×10-6～205.5×10-6之间,平均为(43.6±36.7)×10-6,有效铜含量在0.17×10-6～6.18×10-6之间,平均为(2.70±1.46)×10-6.同时还发现,菜园土壤有效铜含量与全铜含量呈极显著正相关,相关系数为0.717**(n=45,P=0.01,下同),据此认为菜园土壤有效铜的供给是以全铜量为基础的.相关分析还得出,全铜含量与总有机碳和易氧化碳含量均呈极显著正相关,相关系数分别为0.695**和0.594**;有效铜含量也与总有机碳和易化有机碳含量呈极显著正相关,相关系数分别为0.666**和0.557**,这表明施用有机肥料可能是菜园土壤铜营养的重要来源之一.另外,菜园土壤铜的有效性也有随土壤总有机碳和易氧化有机碳含量的提高而增大的趋势,这对一般情况下提高土壤的供铜强度是有益的.但是,倘若土壤中已积累了过量的铜,则有可能加剧铜的毒害,蔬菜生产和菜园土壤管理中都应予以足够的重视.     

腐植酸溶液声化学降解过程中的紫外光谱研究

研究了腐植酸溶液超声声化学降解过程中近紫外光谱在190-320 nm间的变化,证明超声波对腐植酸有明显的降解作用,并测定了降解过程中不同pH值条件下TOC的变化,对降解过程的自由基氧化历程进行了分析。     

Determination of the effect of Quercetinon oxidant- antioxidant parameters in the blood and liver tissues of rats given sodium fluoride experimentally

AimThe purpose of the study is to research the effect of quercetin, which has a good antioxidant characteristic in rats exposed to sodium fluoride (NaF) toxication, on oxidant and antioxidant activity in liver tissue and erythrocyte.Material and method40 Swiss albino male rats with a weight of approximately 20–25 gr were used in the study. The rats were separated into 4 equal groups (n = 10). The first group, the control group, was given normal drinking water; the second group was given 12 mg/kg/day NaF; the third group was given 40 mg/kg/day quercetin; the fourth group was given 12 mg/kg/day NaF+40 mg/kg/day quercetin orally for 30 days. As a result of the experiment, plasma AST and ALT activities were found. Total oxidant capacity (TOC) and total antioxidant capacity (TAC) analyses were made in liver tissue and erythrocyte hemogenisate. Histopathological analyses of the liver tissue were conducted.ResultsNo changes were found in plasma ALT activities between groups. Increases were found in AST activity of all groups. While erythrocyte TAC level was found to increase in fluorine and fluorine + quercetin group when compared with the control group, erythrocyte TOC level was found to increase in all groups when compared with the control group. No significant change was found in TOC and TAC levels in the liver tissue. In liver tissue histopathology, while hydropic degeneration and cellular necrosis were found in vena centralis area in fluorine group, hydropic degeneration was found in heptocytes in centrilobular area in the quercetin group. In the fourth group, hydropic degeneration and centrilobular necrosis were more severe. It was found that in rats which are given NaF experimentally, fluorine and quercetin caused histopathological degenerations in the liver tissue during this time.ConclusionWhile no changes were found in TOC and TAC levels of liver tissue, antioxidant capacity was found to be stimulated in fluorine groups in erythrocyte.     

十二烷基苯磺酸钠的超声降解研究

采用频率为１．８ＭＨｚ,声强近似为５Ｗ·ｃｍ~－２的超声波,在固定式声化学的应器内研究了初始浓度为２００ｍｇ／Ｌ－４００ｍｇ／Ｌ的十二烷基苯磺酸钠（ＤＢＳ）溶液的声化学降解情况．实验表明,浓度的改变对ＴＯＣ的削减率无明显的影响,溶液的ＰＨ值对降解率则有显著影响,碱性条件下（ＰＨ＝１３）,ＤＢＳ几乎无降解,酸性条件下（ＰＨ＝３）ＴＯＣ削减率≤１０％．通过分析降解过程中溶液的紫外光谱（１９０－３４０ｎｍ）,发现降解过程中有复杂的中间产物生成,包括小分子烃类碎片及硝基化合物。我们认为,能使溶液表面张力。降低的表面活性剂,其声化学降解率低的原因在于,溶液表面张力下降后影响了溶液中空化效应的产生,从而降低了溶液中声化学反应的强度,致使ＴＯＣ削减率不高。     

基于紫外-可见光谱的水质TOC定量分析方法

地表水资源安全关系到国民健康、生态环境稳定和经济可持续发展,具有重要战略意义.总有机碳(T OC)是一种衡量水体中有机物含量的综合指标,其在水环境监管和治理中具有重要价值.传统检测方法通过高温催化氧化测定水样中T OC含量具有耗时较长、操作复杂的局限性,紫外-可见光谱技术具有检测速度快、操作简单的优势,因而在水质在线检...