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在弱碱性介质中,α-萘酚被双乙酰氧化为α-萘醌,α-萘醌与肌酸生成荧光化合物,该化合物与十六烷基三甲基溴化铵生成离子缔合物,使体系的共振光散射增强,在1.44×10-9~2.00×10-7mol/L范围内,共振光散射强度(RLS)与α-萘酚浓度呈良好线性关系,回归方程为:△I=186.9c(×10-8mol/L)+84.89,r=0.999 1,检出限为4.31×10-10mol/L,样品的加标回收率为96.0%~104.0%,RSD=0.80%~3.42%,该方法可用于尿液中痕量萘酚的测定。 相似文献
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对α-磺基脂肪酸甲酯钠盐的性能作基础研究,对其在餐具洗涤剂中的应用配方及使用效果进行了研究。研究结果显示,复配α-磺基脂肪酸甲酯钠盐的餐具洗涤剂配方,增稠性、温和性、泡沫性和去污力都有不同程度的提升。 相似文献
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以三氯氧磷、二元醇(酚)、正十二醇为原料,合成了4种双十二烷基双磷酸酯(HDP,DGDP,BDP,PDP)。产物经无水乙醇重结晶提纯后,通过IR、1HNMR、质谱和电位滴定进行了结构表征。25℃时,它们的电离常数分别为:2.76×10-5mol/L(HDP),3.940×10-4mol/L(DGDP),1.595×10-4mol/L(BDP),4.255×10-3mol/L(PDP)。20℃时,它们的临界胶束浓度分别为:3.5×10-4mol/L(HDP),9.0×10-4mol/L(DGDP),1.1×10-3mol/L(BDP),1.3×10-3mol/L(PDP);在临界胶束浓度处的表面张力分别为:30.38 mN/m(HDP),34.49 mN/m(DGDP),35.31 mN/m(BDP),36.14 mN/m(PDP)。差热分析表明,4种产物的分解温度分别为:231℃(BDP),251℃(HDP),227℃(PDP),249℃(DGDP);初熔温度分别为:87℃(BDP),80℃(HDP),97℃(PDP),72℃(DGDP)。 相似文献
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脂肪酸单乙醇酰胺硫酸酯盐的物化性能 总被引:1,自引:0,他引:1
用滴体积法测定了纯化脂肪酸单乙醇酰胺硫酸酯盐(MSN)系列产品水溶液的表面张力,发现当MSN疏水基碳数(n)由10增至16时,其表面过剩浓度(Γm)由2.37×10-6mol/m2增至2.88×10-6mol/m2,临界表面张力(γCMC)由28.79 mN/m降至23.86 mN/m,降低表面张力20 mN/m所需浓度的负对数(pC20)由3.53升为5.54,临界胶束浓度(CMC)由1.40×10-3mol/L降为0.52×10-3mol/L。在所测定的温度(25℃)下,logCMC=-2.13-0.07n;在胶束化过程中,TΔS0m ic对ΔG0m ic的贡献比ΔH0m ic大,MSN胶束化的主要驱动力是熵变。 相似文献
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CTAB/正丁醇/异辛烷反胶团法纯化α-淀粉酶 总被引:2,自引:0,他引:2
以CTAB/正丁醇/异辛烷构成反胶团系统,通过反胶团萃取方式纯化精制α-淀粉酶。最佳反应条件为:萃取温度40℃,水相组成为NaCl 0.03 mol/L,pH12.0,有机相∶无机相=1∶2,振荡时间10 min;反萃取最佳条件为:温度60℃,水相组成为KCl 3 mol/L,pH4.0,有机相∶无机相=2∶1,反萃取振荡时间10 min。在上述条件下,经过一个萃取与反萃取循环后,α-淀粉酶的萃取率最高可达90.78%。 相似文献
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研究了苯甲醛、苯甲酸的紫外吸收特性,建立了同时测定两者含量的方法。发现了以无水乙醇为溶剂,苯甲醛、苯甲酸及其混合物在234 nm处的吸收值只与两者总浓度有关,250 nm处的吸收值与苯甲醛浓度成正比。给出了含量的计算公式为:C苯甲醛=9.074×10-5A250(mol/L),C苯甲酸=1.168×10-4A234-9.074×10-5A250(mol/L)。混合物的检出限为0.17×10-5mol/L,苯甲醛的检出限是0.435 6×10-6mol/L。苯甲醛的平均RSD为0.86%,平均加标回收率是100.1%,相对误差值为1.24%;苯甲酸的平均RSD为0.41%,平均加标回收率是100.7%,相对误差值是-0.37%。 相似文献
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温度及无机盐对LMEE和SDS混合溶液表面张力的影响 总被引:9,自引:1,他引:9
通过表面张力的测定,研究了温度和不同无机盐对月桂酸甲酯乙氧基化物(laurylmethylesterethoxylate,简称LMEE)与十二烷基硫酸钠(SDS)复配物表面张力及临界胶束浓度(CMC)的影响。研究表明:混合体系的CMC在很宽的复配比例内出现最低值,25℃、未加无机盐时可使CMC最低降至3 8×10-5mol/L;温度对复配体系表面张力的影响较小,温度上升复配物的CMC略有降低。3种价态无机盐的加入均可使复配物的CMC有所降低,但与单一表面活性剂相比,温度和无机盐对复配物的CMC影响均不大,说明复配体系的抗温变及抗盐能力均有增强。 相似文献
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含酯基Gemini双季铵盐表面活性剂的合成及应*用 总被引:1,自引:0,他引:1
以环氧氯丙烷(EPIC)与十二烷基二甲基胺在丙酮溶剂中反应,然后与己二酸酯化合成含酯基Gem in i型季铵盐表面活性剂:3,3′-己二酰氧基-2,2′-二羟基-二丙基-双(十二烷基二甲基氯化铵),它可生物降解。用正交实验法对其合成条件进行了优化,在优化的合成条件下反应产率达65.3%。用IR1、HNMR、元素分析方法对产物结构进行了表征。其性能测试结果显示,临界胶束浓度为1.43×10-5mol/L,表面张力为38.7 mN.m-1,有优良的织物柔软性能。 相似文献
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脱氢枞酸蔗糖酯的无溶剂法合成 总被引:1,自引:0,他引:1
用精制的脱氢枞酸,在n(硫酸二甲酯)∶n(脱氢枞酸)=1∶1,碳酸钾为催化剂,反应时间为4 h,丙酮回流条件下,得到脱氢枞酸甲酯,产率为75%。脱氢枞酸甲酯与蔗糖在熔融下通过酯交换反应生成脱氢枞酸蔗糖酯,最佳条件为:n(脱氢枞酸甲酯)∶n(蔗糖)=1∶1.5,m(催化剂碳酸钾)∶m(反应物)=0.05∶1,m(乳化剂硬脂肪酸钠)∶m(反应物)=0.1∶1,温度140℃,压强0.5 kPa,反应时间5 h,产率可达32%,测定了其表面张力和乳化能力。临界胶束浓度(CMC)为:9.0×10-3mol/L;此时表面张力为18.42 mN/m。 相似文献
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采用尿素包合法分离棕榈油甲酯化物中不同碳链长度的脂肪酸甲酯,为农产品涂膜保鲜材料的开发提供原料。重点考察了尿素用量、溶剂用量、包合时间和包合温度对分离效果的影响,并以尿素用量、95%乙醇用量、包合温度为三因素,C16脂肪酸甲酯和C18脂肪酸甲酯的纯度为二指标,根据Box-Benhnken中心组合试验设计原理,利用Designexpert7.0.1软件分析优化了分离的工艺条件并建立了回归模型。优化的最佳工艺条件如下:在棕榈油甲酯化物用量为20g,尿素用量为35g,95%乙醇用量为120mL,包合温度为5℃,包合时间为16h的条件下,饱和脂肪酸甲酯相中C16脂肪酸甲酯的含量达78.5%,不饱和脂肪酸甲酯相中C18脂肪酸甲酯的含量达93.1%,分别比原料提高36.4%和40.8%。 相似文献
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A fractionally distilled C14−C16 fatty acid methyl ester, derived from palm oil, was sulfonated with gaseous SO3 in a falling film reactor to form an α-sulfo fatty acid methyl ester (α-SF; unbleached and unneutralized form). The included
dark-colored impurities were then separated from α-SF as a diethyl ether-insoluble matter. After purification by thin-layer
chromatography, the colored species were analyzed by ion-exchange chromatography, gel-permeation chromatography, and nuclear
magnetic resonance spectrometry. These data suggested that the colored species were polysulfonated compounds with conjugated
double bonds. Minor components in the raw fatty acid methyl ester, found by gas chromatography/mass spectrometry, were spiked
into the purified methyl palmitate and then sulfonated. The unsaturated methyl ester and hydroxy ester showed the worst color
results. The methyl oleate and methyl 12-hydroxystearate were then sulfonated and analyzed. Deep black products were obtained,
which showed the same properties as the colored species in α-SF. It was concluded that low levels of unsaturated fatty acid
methyl esters and hydroxy esters in the fatty acid methyl ester are the main causes of the coloring. 相似文献
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以十二胺、丙烯酸甲酯、对苯二甲酰氯等为主要原料经加成、酰胺化、皂化等反应合成了酰胺型羧酸盐Gemini表面活性剂——N,N′-双十二烷基对苯二甲酰胺丙酸钠(SDPA-12)。经单因素考察酰胺化反应得出最佳工艺条件为:n(N-十二烷基-β-氨基丙酸甲酯)∶n(对苯二甲酰氯)=2.2∶1,35℃回流反应8h,收率68.7%;经红外光谱、元素分析和核磁共振波谱对产物结构进行了确认。性能测定表明,25℃时SDPA-12的表面张力为27.09mN/m,临界胶束浓度为1.83×10-5mol/L。 相似文献
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Synthesis,Characterization and Exploratory Application of Anionic Surfactant Fatty Acid Methyl Ester Sulfonate from Waste Cooking Oil
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Yueming Jin Senlin Tian Jiali Guo Xiao Ren Xinyan Li Shumei Gao 《Journal of surfactants and detergents》2016,19(3):467-475
The environmentally friendly anionic surfactant fatty acid methyl ester sulfonate (MES) was prepared by esterification of waste cooking oil (WCO), a low-cost raw material, followed by sulfonation with chlorosulfonic acid. MES production from WCO (W-MES) gave yields up to 78 %. Such a value is only slightly lower than the one obtained from soybean oil (S-MES), 82 %, and almost the same as that from reused cooking oil (R-MES), 76 %. According to the two-phase titration results, the content of the active component, α-MES, in S-MES, R-MES and W-MES was equal to 76.82, 69.19 and 66.60 %, respectively. The disalt, RCH(CO2Na)SO3Na, contents were instead 3.2, 3.8 and 4.7 %, respectively. As proved by the results of the FTIR and NMR characterizations, the chemical structure of W-MES is almost the same as that of S-MES and R-MES. The critical micelle concentration of W-MES is 5.38 mmol/L and the corresponding surface tension is 32.3 mN/m. The hydrophile-lipophile balance value of W-MES is 12.33, which indicates that it can form oil/water emulsions. The three MES demonstrated the same adsorption efficiency, yielding a pC20 value of 3.22, and similar foam stability. Their detergency can be up to 75 % at a concentration of 400 mg/kg and the tolerance to Ca2+ is higher than the one exhibited by linear alkylbenzene sulphonic acid and alpha olefin sulfonate. Additionally, W-MES shows a considerable solubilization capacity towards polycyclic aromatic hydrocarbon as the molar solubilization ratios to pyrene, phenanthrene and acenaphthene in a 30 mmol/L solution are 1.22 × 10?3, 2.67 × 10?3 and 3.81 × 10?3, respectively. 相似文献