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取水样25mL,加入无水硫酸钠3.0g,加入环己烷2.0mL,振荡萃取3min。移取萃取了邻苯二甲酸二(2-乙基己基)酯(DEHP)的上层有机相2.0μL注入HP-5毛细管柱(30m×0.32mm,0.25μm)色谱分离后进行质谱测定。DEHP的质量浓度在50.0μg.L-1以内与其峰面积呈线性关系,方法的检出限(3S/N)为0.052μg.L-1。分析了早、中、晚不同时间的天津市自来水,并用标准加入法做回收试验,测得回收率在97.0%~109.4%之间,测定值的相对标准偏差(n=6)均小于2.5%。 相似文献
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钴离子在P507为载体的支撑液膜中的传输 总被引:5,自引:0,他引:5
本文用国内的膜材料设计了以2-乙基已基膦酸单(2-乙基已基)酯(HEH(EHF),P_(507))为载体的支撑液膜迁移钴的实验,获得的数据为深入实验提供了依据.基本原理支撑液膜(SLM)是依靠微孔塑料薄膜(支撑体)微孔的毛细管作用将含萃取剂(载体)的有机溶液吸附在支撑体上.P_(507)萃取钴表示为: 相似文献
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用两相充分混合法,在298±1K下研究了HEH[EHP]-正庚烷-1.0mpL·L-1(Na,H)NO3体系中萃取Fe(Ⅲ)的动力学过程。认为界面慢反应为速率控制步骤。 相似文献
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Hans-Detlev Gilsing Jürgen Angerer Dietrich Prescher 《Monatshefte für Chemie / Chemical Monthly》2003,134(9):1207-1213
Summary. Two ring-deuterated major metabolites of bis(2-ethylhexyl) phthalate were obtained in excellent yields by means of an improved oxidation procedure. The by-product of their interconversion by Swern oxidation is elucidated and a possible mechanism of its formation is proposed.Received February 27, 2003; accepted March 3, 2003
Published online July 28, 2003 相似文献
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《Analytical letters》2012,45(4):467-480
Abstract The tenaammetric behavior of di-(2-ethylhexyl)phosphoric acid (D2KHPA) was investigated by non-phase-selective AC polarography. D2EHPA produces in alkali sulfate supporting electrolytes a decrease of the capacitive current in the region of zero-charge potential, as well as a tensammetric peak located between -1.0 and -1.3 V vs. SCE. In the same range, the second harmonic has a characteristic maximum. The pH of the solution and the nature of the cation in the supporting electrolyte affect both the height and the position of the tensammetric peaks. The tensammetric method allows determination of D2EHPA at concentrations ranging from 0.5 to 200 mg/1. Maximum sensitivity is obtained by measuring the second harmonic. 相似文献
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《Analytical letters》2012,45(7-8):625-638
Abstract Analytical methods are described for determining the concentration ratio of trioctylphosphine oxide (TOPO) and di(2-ethylhexyl)phosphoric acid (D2 EHPA) in hydrocarbon solvents or in mixtures where the D2 EHPA is the solvent. The Electron Spectroscopy for Chemical Analysis (ESCA) method was used to analyze the mixtures for the relative amounts of phosphine oxide-phosphorus to phosphoric acid-phosphorus as well as the variance with the mixture composition of the Ols/P2p signal intensity. The nmr signal strength of the protons of the oxymethylene group of the D2 EHPA and the signal strength of the other protons of D2 EHPA and TOPO were measured in solutions of varying concentrations of D2 EHPA and TOPO. Mass spectral comparisons of the molecular ion strengths of TOPO and D2 EHPA were also correlated with mixture composition. 相似文献
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Summary. The addition of triphenylphosphine to dimethyl acetylenedicarboxylate in the presence of arylsulfonylglycyl chlorides leads
to 1,4-bis-arylsulfonyl-tetrahydropyrazine-2,5-diones and dimethyl (E)-2-chloro-2-butenedioate.
Corresponding author. E-mail: isayavar@yahoo.com
Received June 3, 2002; accepted June 10, 2002 相似文献
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Poly(vinyl chloride) based membranes of di-(2-ethylhexyl)phosphoric acid (DEHPA) and dibutyl(butyl)phosphonate (DBBP) have been prepared and investigated as VO2+-selective sensors. The membranes containing DEHPA/DBBP and sodium tetraphenylborate, an anion excluder, show near-Nernstian/Nernstian response in the concentration range 10−5–10−1 M. The sensors exhibit a fast response time and good selectivity for VO2+ over a number of other cations. Quantitative determination of vanadium in waste V2O5 catalyst has been achieved by these sensors and they have also been used as indicator electrodes for the determination of the end point in the potentiometric titration of VO2+ against EDTA. 相似文献
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Coupled transport of Eu(III) ions through a bulk liquid membrane containing mono(2-ethylhexyl)2-ethylhexyl phosphonate [HEH(EHP)] in kerosene has been examined. The influences of the carrier concentration, the HCl concentration in the stripping solution, the pH in the feed solution and the temperature were investigated. The transport of the Eu(III) ions is coupled by counter-transport of protons. The kinetics of the Eu(III) transport could be analyzed in the formalism of two consecutive irreversible first order reactions. The pseudo-first order apparent rate constants of the interfacial transport of the Eu(III) species are determined, varying temperature. The activation energy values are 14.0±1.0 and 54.0±3.4 kJ mol−1 for extraction and stripping, respectively. 相似文献
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Summary. Stable crystalline phosphorus ylides are obtained in excellent yields from the 1:1:1 addition reaction between 1-methylparabanic
acid (1-methylimidazoline-2,4,5-trione) and dialkyl acetylenedicarboxylates in the presence of triphenylphosphine. These ylides
exist in solution as a mixture of two geometric isomers. This is due to the restricted rotation around the carbon–carbon partial
double bond resulting from conjugation of the ylide moiety with the adjacent carbonyl group. These ylides undergo smooth intramolecular
Wittig reaction followed by an electrocyclic ring opening to produce dialkyl (E)-2-(1-methyl-2,5-dioxo-3-imidazolin-4-yl)-but-2-enedioates in good yields.
Corresponding author. E-mail: isayavar@yahoo.com
Received March 26, 2002; accepted (revised) April 24, 2002 相似文献
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A new method is proposed for the extractive Chromatographic separation of antimony. Antimony is extracted from 0.001–0.5M hydrochloric acid by a silica gel column coated with bis (2-ethylhexyl) phosphoric acid stripped with 2–8M hydrochloric, nitric or sulphuric acid, and determined spectrophotometrically at 555 nm as its complex with phenylfluorone. Antimony can thus be separated from a large number of elements, including iron, manganese, copper and thallium. Arsenic, antimony, bismuth and tin can be sequentially separated. 相似文献
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HDEHP和HEHEHP界面性质及添加剂对界面性质的影响 总被引:1,自引:0,他引:1
测定了HDEHP、HEHEHP、TOPO、TBP、SDS和CTMAB的煤油溶液与硫酸盐水溶液所构成的液-液体系的界面张力,考察了水相pH对界面张力的影响,求得这些化合物的界面吸附常数,计算出饱和吸附时界面吸附分子的截面积,提出了用Cmin计算活性剂分配比的方法,研究了向HDEHP或HEHEHP体系中添加TOPO(或TBP)、SDS、CTMAB时界面张力的变化及其对萃取速率的影响。界面化学反应控制的萃取金属阳离子过程的速率将因添加剂占据界面和(或)形成界面负电层而降低,因添加剂与萃取剂形成界面活性较强的分子缔合物对金属的萃取而提高。 相似文献
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Summary. The synthesis of an oxidative major metabolite of bis(2-ethylhexyl) phthalate is described. The target molecule and its ring-deuterated isomer were obtained via acylation of the appropriate -hydroxy benzyl ester or the corresponding carboxylate with phthalic anhydride or phthalic anhydride-d4. All transformation steps proceed with high yields. 相似文献
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《Analytical letters》2012,45(15):1517-1535
Abstract A method for the analysis of tissue DEHP levels was developed. Tissue homogenates were extracted with a chloroformrmethanol solution, followed by the addition of 1 g baked alumina to clean up the heavy matrices of the tissues. DEHP levels in tne tissues were determined by gas chromatography. Percent recovery of DEHP from the tissues ranged between 72.2 and 83.3%. An experimentally produced acute renal failure in dogs (performing bilateral nephrectomy) was used for comparison of DEHP distribution in tissues from Control, Sham-Operated and Nephrectomized dogs. The highest concentration of DEKP was found in lung tissues of all three groups. DEHP levels in tissues of Nephrectomized dogs were significantly higher than those of Control and Sham-Operated dogs. With the exception of brain and liver, no significant difference in tissue DEHP levels were noted for Control and Sham-Operated dogs. Liver DEHP levels were 39.4 and 65.4 μg/g tissue for the Control and Sham-Operated dogs, respectively. DEHP was found in various tissues of some, but not all of the subjects who received hemodialysis treatments, blood transfusions or blood which was previously in contact with PVC. No sufficient information is available at the present time to draw a relationship between exposure to DEHP and unchanged DEHP content in the tissues. However, DEHP does appear to accumulate in tissues and could be detected at death from some, but not all patients. It is more likely, however, that DEHP undergoes rapid metabolism in tissues. 相似文献
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Summary High-performance liquid chromatography (HPLC) was used for the routine monitoring of the plasticizers di(2-ethylhexyl) phthalate
(DEHP) and tri(2-ethylhexyl) trimellitate (TOTM), in blood products. It allows easy sample clean-up, solvent extraction using
Celite 545 sorbent, good recoveries and opportunity to inject large number of samples without effect on column performance.
The plasticizer levels were investigated in two types of poly(vinyl chloride) (PVC) bags containing whole blood plasma, platelet
concentrates (PCs) during blood taking and storage. 相似文献