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101.
102.
Transport phenomenon of three sulfonated azo dyes, C.I. Acid Red 88, C.I. Direct Yellow 12, and C.I. Direct Blue 15 into water-swollen cellulose membranes has been analyzed on the basis of parallel transport theory by surface and pore diffusion. Langmuir equation was applied into the mass balance equation to estimate dye concentration in the pores. The results were compared with the results obtained by applying Freundlich equation in our previous papers. The surface diffusivity (D
s) and the pore diffusivity (D
p) for the parallel diffusion model obtained by applying Langmuir equation agreed with those obtained by applying Freudlich equation. The theoretical concentration profiles for parallel diffusion calculated usingD
s andD
p coincided accurately with the experimental data when we applied either Langmuir or Freundlich equations. 相似文献
103.
104.
甲烷直接氧化制甲醇Ⅲ.反应气吹扫催化膜反应器(RSCMR) 总被引:2,自引:0,他引:2
用溶胶-凝胶法制备了“SiO_2/陶瓷”非对称无机膜,并用该膜制备了反应气吹扫催化膜反应器(RSCMR)装置。在RSCMR上考察了甲烷一步催化氧化制甲醇反应。结果表明,在研究的范围内,增加氧气或甲烷的浓度和吹扫气的流速(即总的反应气流量)有利于提高甲醇的收率;甲醇在反应条件下的热不稳定性是影响目标反应选择性的重要原因。RSCMR较膜反应器(CMR)系统能更有效地抑制甲醇的热分解,因而可得到较CMR更高的甲醇收率。当反应温度为700℃时,甲醇的收率在CMR中为0.5g/m ̄2h,在RSCMR中可达0.9g/m ̄2h。 相似文献
105.
106.
An automated sample pretreatment of human blood plasma for liquid chromatographic determination of three antidepressant drugs, dibenzepine; a tricyclic antidepressant (TCA), reboxetine; a selective noradrenaline reuptake inhibitor (SNRI) and fluvoxamine; a selective serotonin reuptake inhibitor (SSRI), based on supported liquid membrane (SLM) for unsurpassed sample clean-up and analyte enrichment, has been developed. The chromatograms after enrichment of plasma blank and aqueous blank are virtually indistinguishable. The entire analytical procedure revealed good linearity and low detection limits of 5, 15 and 20 ng mL–1 for dibenzepine, reboxetine and fluvoxamine, respectively. No carry-over effects were noted. The repeatability of extraction at three concentrations in the range 40–150 ng mL–1 for the three drugs was between ca. 3% and 7% as relative standard deviation. The reproducibility relative standard deviation during three different days (replacing the membrane each day) was not significantly higher. 相似文献
107.
108.
109.
Páez-Hernández ME Aguilar-Arteaga K Valiente M Ramírez-Silva MT Romero-Romo M Palomar-Pardavé M 《Analytical and bioanalytical chemistry》2004,380(4):690-697
The results presented in this work deal with the prime application of activated composite membranes (ACMs) for the transport of Hg(II) ions in a continuous extraction–re-extraction system using di-(2-ethylhexyl)dithiophosphoric acid (DTPA) as carrier. The effects of variables such as the pH, the nature of the acid and the concentration of the casting solutions on the transport of Hg(II) are also investigated. When the ACM was prepared with a 0.5 M DTPA solution and when the feed solution contained 2.5×10–4 M Hg(II) in 0.1 M HCl, the amount of mercury extracted was greater than 76%. The re-extracted mercury was subsequently recovered by means of a stripping phase comprising 0.3 M thiourea solution in 2 M H2SO4, yielding 54% of the initial amount of mercury after transport had taken place for 180 min. 相似文献
110.
壳聚糖/聚丙烯酸聚电解质复合物膜对水/有机液体系的渗透汽化性能 总被引:8,自引:0,他引:8
以壳聚糖和聚丙烯酸为原料制备了聚电解质复合物膜,并对其分离水/乙醇体系的渗透汽化特性和浓度,温度,化学组成等因素的影响进行了研究,发现后处理方法对复合物膜的分离性能影响很大。同时对其它水/有机液体系,该膜也具备优异的分离性能。 相似文献