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1.
以1-(2-吡啶偶氮)-2-萘酚为络合剂,在pH 7.0,用Triton X-100非离子表面活性剂浊点萃取水样中痕量镍.表面活性剂相用硝酸-甲醇(1 9)混合液0.5 mL分散,所得溶液直接引入仪器进行火焰原子吸收测定,方法的检出限(3σ)为3.77×10-3mg·L-1,应用所提出方法测定了河水样品,测定结果的相对标准偏差(n=6)为2.98%. 相似文献
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Triton X-100增敏光度法测定铝土矿中的微量钪 总被引:1,自引:0,他引:1
研究了在HCl溶液中微量钪(Ⅲ)-偶氮氯膦Ⅲ(CPAⅢ)之间的配合反应。结果表明,在0.5mol/LHCl溶液中和TritonX 100的存在下,有色溶液的最大吸收波长为680nm,表观摩尔吸光系数为2.62×104L·mol-1·cm-1。钪(Ⅲ)质量浓度在0~0.45mg/L范围内符合比耳定律,钪(Ⅲ)的加标回收率在98.0%~105.1%之间,RSD(n=6)为2.1%~2.6%。可用于铝土矿中的微量钪的测定。 相似文献
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质粒DNA的阴离子交换色谱法纯化及内毒素去除 总被引:7,自引:0,他引:7
采用Fractogel EMD TMAE(M)强阴离子交换介质分离纯化质粒脱氧核糖核酸(DNA),该介质对质粒DNA的动态载样量达0.62 mg/mL。用Triton X-114或Triton X-100预先处理质粒DNA的裂解澄清液后,经阴离子交换色谱分离纯化获得的质粒DNA中内毒素含量分别为6.42 EU/mg和9.50 EU/mg,显著低于未经Triton处理的裂解澄清液(67.82 EU/mg)。该法实现了阴离子交换色谱一步纯化质粒DNA的目的,具有简便、省时、成本低等特点。 相似文献
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The polyoxyethylene chain of non-ionic surfactant Triton X-100 [4-(1,1,3,3-tetramethylbutyl) phenyl polyethylene glycol,TX-100] was degraded by permanganate in the presence of HClO4. The oxidative degradation rate and cloud point have been obtained as a function of [surfactant], [permanganate], [HClO4], and temperature. Dependence of the reaction rate on adding inorganic salts (Na4P2O7, NaF and MnCl2) was also examined. The oxidation rate increased with increase in [TX-100] and [H+]. The higher order kinetics with respect to [TX-100] at lower [H+] shifted to lower order at higher [H+]. The cloud point of TX-100 (67°C) shifted to lower temperature (23±0.5°C) after oxidative degradation of the polyoxyethylene chain. Evidence of complex formation between TX-100 and MnO
4
−
was obtained spectrophotometrically. Presence of the primary alcoholic (–OH) group in the TX-100 skeleton is responsible for the degradation of oxyethylene chain. Both monomeric and aggregated TX-100 molecules are oxidized by permanganate. A catalytic oxidation mechanism is proposed on the basis of the experimental findings. 相似文献
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AOT/Triton X-100混合反胶束体系中假丝酵母脂肪酶催化蓖麻油水解的活性 总被引:2,自引:0,他引:2
研究了二(2-乙基己基)琥珀酸磺酸钠(AOT)/Triton X-100混合反胶束体系中假丝酵母脂肪酶(candida rugosa lipase)催化蓖麻油水解的反应. 考察了Triton X-100占总表面活性剂的摩尔分数(x(Triton X-100))、水与总体表面活性剂的摩尔比(ω0)、pH值、反应温度以及底物蓖麻油的浓度等因素对酶活性的影响. 研究结果表明, 加入非离子表面活性剂Triton X-100可以使假丝酵母脂肪酶的活性得到显著提高, 但是当底物蓖麻油的浓度大于0.24 mol·L-1时, 会对假丝酵母脂肪酶产生抑制作用. 相似文献
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TritonX-100-5-Br-PADAP光度法测定发样中铁 总被引:2,自引:0,他引:2
在表面活性剂Triton X-100存在下,以5-Br-PADAP作显色剂,光度法测定发样中铁,结果在所选浓度范围内线性关系良好,稳定时间长,回收率平均为98.14%。 相似文献
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Jigisha Parikh Jitendra Rathore Darshak Bhatt Meghal Desai 《Journal of Dispersion Science and Technology》2013,34(10):1392-1398
The present study investigates the effect of different additives on the cloud point (CP) of nonionic surfactants Triton X-100 (TX-100) and Triton X-114 (TX-114) in aqueous solutions. The thermodynamic parameters of these mixtures were calculated at different additive concentrations. The cloud point of nonionic surfactants TX-100 and TX-114 decreased with the increment of electrolyte concentrations and increased with alcohol concentrations. The standard Gibbs free energy was found to be positive for both the surfactants, whereas the enthalpy and the entropy of the clouding phenomenon were found to be positive with alcohols and negative with electrolytes. The overall clouding process was endothermic for alcohols and exothermic for electrolytes. 相似文献
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A novel and sensitive cloud point extraction procedure for the determination of trace amounts of malachite green by spectrophotometry was developed. Malachite green was extracted at pH 2.5 mediated by micelles of nonionic surfactant Triton X-100. The extracted surfactant-rich phase was diluted with ethanol and its absorbance was measured at 630 nm. The effect of different variables such as pH, Triton X-100 concentration, cloud point temperature and time and diverse ions was investigated and optimum conditions were established. The calibration graph was linear in the range of 4-500 ng mL−1 of malachite green in the initial solution with r = 0.9996 (n = 10). Detection limit based on three times the standard deviation of the blank (3Sb) was 1.2 ng mL−1 and the relative standard deviation (R.S.D.) for 20 and 300 ng mL−1 of malachite green was 1.48 and 1.13% (n = 8), respectively. The method was applied to the determination of malachite green in different fish farming and river water samples. 相似文献
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Triton X—100—DPSA法测定血铅 总被引:2,自引:0,他引:2
着重研究了在微分电位溶出法测定血铅中加入TritionX-100非离子型表面活性剂的效果,发现它能改善溶出峰形,减少误差,明显地提高分析的灵敏度,铅溶出峰与浓度在0.002~0.01mg/L范围呈线性关系,回归方程式和相关系数为y=14.57+757.14x,r=1,其相关系数比原法稍有提高,变异系数7.1%,回收率96.8%~103.9%,本法取血量少,血样经微汉消解即可测定,简便快速准确,便基 相似文献
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The effect of Na2SO4 and PhCOONa on the aquation of [Fe(Me4phen)3]2+ has been investigated in pure Triton X-100 as solvent. The rate and mechanism of the aquation are explained in terms of changes in the mobility, activity and structure of H2O in the restricted environment of water pockets in the Triton X-100 solvent. 相似文献
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Lin Guo & Ying-Qiu Liang 《Supramolecular chemistry》2013,25(1):31-40
The location and aggregation of 5,10,15-tris(4-hydroxyphenyl)-20-(hexadecyloxyphenyl)porphyrin (P) in nonionic polyoxyethylene (9.5) octylphenol (Triton X-100) micelle solutions were studied by means of UV–Vis and fluorescence spectra. P forms premicelle surfactant–porphyrin aggregates when the surfactant concentration is below and approaching the CMC. In Triton X-100 micelle solutions, different types of H-aggregates of P were formed when the concentration of P is higher than 3.9×10-6?mol?dm-3. As the bulk pH is changed, a transfer process for the porphyrin moiety in Triton X-100 micelle occurs. In neutral Triton X-100 micelle solutions, P may be located at the inner layer of the micelle; in basic conditions, the porphyrin moiety may transfer to the outer surface of the micelle. The kinetic study of porphyrin complexed with Cu(II) in Triton X-100 micelle solutions shows that the metalation rate could be controlled by changing the pH. 相似文献
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The hydrolysis of cephanone in water and micelles with different charges was studied by UV-vis absorption spectroscopy. The change of pH with the hydrolysis of cephanone was determined. The mechanism of the hydrolysis and the effect of the acidity of the media on the hydrolysis were studied. The results show that the hydrolysis rate of cephanone increases with the acidity. Compared with water, SDS micelles accelerate this hydrolysis, whereas CTAB and Triton X-100 micelles suppress it. The effects of the micelles with different charges on the hydrolysis are explained by the proton concentration of the micro-environment where cephanone exists and by the charge density of the polar group of the cephanone molecules. 相似文献
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Semidifferential electroanalysis is used as an effective method for investigating microstructure and structural transition of Triton X-100 microemulsions. 相似文献
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Nonionic poly(oxyethylene) surfactant with about ten ethylene oxide units and 1-butanol have been studied in reverse micelles
with one nonpolar solvent(n-octane) at different water contents in the presence and in the absence of poly (ethylene oxide) (PEO) using two absorption
probes, methyl orange and methyl blue MB and one spin probe, 5-doxylstearic acid. The study has focused attention on the effect of the addition of PEO on the phase
behavior of the system, the state of water in the reverse micelles, and the locus of PEO solubilized in reverse micelles.
In the presence of PEO, some PEO segments may penetrate into the interface close to the palisade layer of the reverse micelles
and then replace some water molecules, which results in a less close arrangement between the chains of surfactants as well
as between alcohol molecules.
Received: 13 April 1999/Accepted in revised form: 5 November 1999 相似文献
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Derek G. Leaist 《Journal of solution chemistry》1991,20(2):187-197
A modified taylor dispersion technique is used to measure liquid-phase mutual diffusion coefficients D. Rather than inject a narrow band of solution of solute concentration C+C into a carrier stream of composition C, the carrier stream is switched from a solution of composition C-(C/2) to a solution of composition C+(C/2), forming an initially-sharp moving boundary at the tube inlet. D is calculated from the refractive index profile across the broadened boundary at the tube outlet. Since the mean of concentration of the diffusing solute (C) is constant throughout the run, the calculated value of D accurately represents the differential value at C, even if relatively large concentration differences are used or if D is sensitive to composition. The advantages of the technique are illustrated by measuring the diffusion of aqueous Triton X-100, a nonionic surfactant. D is found to drop sharply as the concentration is raised through the critical micelle concentration near 0.15 g-L–1. 相似文献
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参照文献方法合成了BSA保护的水溶性发光金纳米粒子, 并考察了此探针在非离子表面活性剂曲通X-100中的发光行为.根据观察到的发光增强效应, 建立了一种简单的测定曲通X-100的方法.考察了发光金纳米粒子的浓度、体系酸度、反应时间及共存物质对测定的影响.在最佳条件下, 发光强度与曲通X-100的浓度分别在0~150 μmol/L和150~600 μmol/L范围内分段成正比关系.两条工作曲线的交点所对应的浓度与曲通X-100的临界胶束浓度十分吻合, 为胶束形成过程提供了直接的指示.作为一种生物相容性探针, 发光金纳米粒子被用于生物学样品中曲通X-100的分析测定, 结果令人满意. 相似文献
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G. Geeraerts P. Joos 《Colloids and surfaces. A, Physicochemical and engineering aspects》1994,90(2-3):149-154
Considering surfactant solutions at concentrations exceeding the CMC, another relaxation process besides diffusion occurs, also affecting the dynamic surface tension. The latter equilibration process concerns a micellisation/demicellisation process, representing the disintegration of micelles into monomers. The micellisation kinetics are accounted for by adding a single source term to the diffusion equation of the free monomers.
In the present paper the integration of the diffusion equation is avoided by using the concept of the diffusion penetration depth. Nevertheless, when this approximation is made, good agreement is achieved between experiment and theory for micellar Triton X-100 solutions. Moreover, it follows that diffusion of micelles may not be neglected. 相似文献