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甲基环己烷-苯-DMF汽液平衡的研究 总被引:3,自引:2,他引:1
采用改进的Rose釜测定了101.3kPa下苯(1)-DMF(2)、甲基环己烷(1)-苯(2)、甲基环己烷(1)-DMF(2)3组二元体系及甲基环己烷(1)-苯(2)-DMF(3)三元体系的汽液平衡数据。三组二元体系的VLE数据均通过了微分法热力学一致性检验。应用NRTL模型和UNIQUAC模型关联了二元、三元体系的VLE数据。推算了三元体系VLE数据。 相似文献
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通过二次生长法,在b轴取向的晶种层上制备得到b轴取向的TS-1分子筛膜,并对其进行了XRD和SEM表征。详细考察了二次生长液用量及其H2O含量、Ti含量对膜取向性的影响。结果表明,在二次生长液(n(TEOS)∶n(TBOT)∶n(TPAOH)∶n(H2O) =1∶0.008∶0.13 : x)中,当x = 40或x =70时,可以制备得到致密的b轴取向的TS-1分子筛膜;当x = 100时,得不到连续膜层。在二次生长液(n(TEOS) : n(TBOT)∶n(TPAOH)∶n(H2O) =1∶0.008∶0.13∶70)中,二次生长液用量40~60 mL,膜层为b轴取向,但其取向度逐渐降低。在二次生长液(n(TEOS)∶n(TBOT)∶n(TPAOH)∶n(H2O) =1∶y∶0.13∶70)中,当1/y = 125时,可得到b轴取向的TS-1分子筛膜;当1/y=95时,得到a和b轴优先取向的膜层;当1/y=65时,膜层无序生长。 相似文献
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The synthesis of a series of isomer pure mid-position alkylbenzene sulfonates is described. Three isomers—4-(1-ethyldodecyl)benzene sodium sulfonate, 4-(1-butyldecyl)benzene sodium sulfonate, and 4-(1-hexyloctyl)benzene sodium sulfonate—were synthesized. High performance liquid chromatography (HPLC) indicated that the isomers were of 99.9%, 96.2%, and 97.5% purity, respectively. Their structures were characterized to be correct by electrospray ionization-mass spectrometry (ESI-MS), 1H NMR, and 13C NMR investigations. Furthermore, the purity and structure of the three kinds of intermediates were also determined by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). 相似文献
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Aflatoxin M1 (AFM1) levels were determined in 600 cheese samples (200 white, 200 kashar and 200 processed cheeses). The samples were collected from some provinces of Turkey and analysed between January 2001 and February 2002 in Bursa, Turkey. AFM1 levels were determined by competitive enzyme-linked immunosorbent assay (ELISA) technique. The highest AFM1 concentration was 800 ng/kg in kashar cheese. AFM1 was detected in 30 (5%) samples consisting of 10 white, 12 kashar and 8 processed cheese. Altogether, the AFM1 levels in 6 of 600 (1%) exceeded the legal limits of 250 ng/kg established by the Turkish Food Codex. 相似文献
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采用作者设计的液液平衡釜,于常压下测定了甲基环己烷(1)-DMF(2)二元系(20.0~47.9℃)的互溶度数据,以及常压、20.O℃和35.O℃下甲基环己烷(1)-苯(2)-DMF(3)三元系和甲基环己烷(1)-苯(2)-DMF(3)-水(4)(DMF/H2O=4∶1,mass比)四元系的LLE数据。 相似文献
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以4,4′-二氨基二苯基甲烷(DDM)、苯甲醛和亚磷酸二乙酯为原料,合成了两种含磷固化剂PM1和PM2,用红外光谱、核磁共振氢谱对PM1和PM2的结构进行了表征。用DDM,PM1,PM2分别固化双酚A型(DGEBA)环氧树脂,得到DGEBA-DDM,DGEBA-PM1,DGEBA-PM2树脂,采用示差扫描量热法、热重分析(TGA)和极限氧指数(LO I)对DGEBA-DDM,DGEBA-PM1,DGEBA-PM2树脂的玻璃化转变温度(Tg)、反应活性、热稳定性和阻燃性能进行了表征。实验结果表明,PM2的反应活性比PM1低;DGEBA-DDM,DGEBA-PM1,DGEBA-PM2树脂的Tg分别为178,112,145℃;TGA结果表明,700℃时DGEBA-PM1和DGEBA-PM2树脂的成炭率分别为29%和35%,而700℃时DGEBA-DDM树脂的成炭率只有19%;DGEBA-PM1和DGEBA-PM2树脂的LO I值由DGEBA-DDM树脂的24%分别增至30%和35%,且阻燃性能大幅度提高。 相似文献
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共沉淀法制备了n(TiO2):n(ZrO2)=4:1,3:2,1:1,2:3,1:4及单一TiO2、ZrO2氧化物,并用浸渍法制备了10% MoO3/TiO2-ZrO2,10% MoO3/TiO2,10% MoO3/ZrO2催化剂。用X射线衍射、N2吸附方法对催化剂进行表征,在间歇式高压反应釜上进行活性评价。结果表明,550 ℃煅烧2 h后,TiO2-ZrO2(1:1),TiO2-ZrO2(2:3),TiO2-ZrO2(3:2)为无定型,其余载体出现不同程度的结晶。复合氧化物的比表面积均大于单一氧化物,其中TiO2-ZrO2(1:1)的比表面积最大(191.2 m2/g)。噻吩的加氢脱硫反应作为模型反应来评价催化剂的活性。催化剂的活性随着ZrO2在复合载体中含量的增加而提高,10% MoO3/TiO2-ZrO2(1:1)的活性最高。当ZrO2含量进一步增加时,催化剂的活性降低,单一ZrO2载体催化剂的活性最低。 相似文献
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疏水性介孔KIT-1分子筛的制备与表征 总被引:1,自引:0,他引:1
在甲苯溶剂中,用三甲基氯硅烷对全硅介孔K IT-1分子筛进行有机改性,制备了疏水性的介孔K IT-1分子筛(记为S-K IT-1分子筛);利用傅里叶变换红外光谱、X射线衍射、低温N2吸附-脱附法对K IT-1和S-K IT-1分子筛的结构进行了表征;通过测定K IT-1和S-K IT-1分子筛在水或正己烷饱和蒸气中的吸附量,考察了S-K IT-1分子筛的疏水性。实验结果表明,S-K IT-1分子筛仍保持了K IT-1分子筛完整的介孔结构,孔径在3nm以上;由于体积较大的—S i(CH3)3基团接枝在K IT-1分子筛的孔道表面,占据了孔道内部空间,使其比表面积、孔体积和孔径减小;同时由于K IT-1分子筛表面亲水性的硅羟基已转变为疏水性的≡S i—O—S i≡键,使S-K IT-1分子筛表现出较好的疏水性。 相似文献
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采用傅里叶变换红外光谱(FTIR)对[(C_2H_5)_3NH]Cl/xAlCl_3-yCuCl 复合离子液体进行了表征,着重比较了 CuCl 含量不同的复合离子液体的 FFIR 谱图;在288 K、搅拌转速1 500 r/min、异丁烷与2-丁烯摩尔比为10:1的条件下,考察了复合离子液体催化剂对异丁烷/2-丁烯烷基化反应的催化性能。实验结果表明,当复合离子液体的 FTIR 谱图在1636~1685 cm~(-1)区域内仅在1 636 cm~(-1)处出现吸收峰时,烷基化产物中三甲基戊烷(TMP)的质量分数小于40%,而当1636~1685 cm~(-1)区域内出现分裂峰(1 636,1 685 cm~(-1)处)时,产物中 TMP 的质量分数大于80%。根据复合离子液体的 FTIR 谱图在1636~1685 cm~(-1)区域内的变化,可以判断复合离子液体中是否存在大量 Al-Cu 配位离子,并可作为评价复合离子液体催化剂烷基化性能的判据。 相似文献
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A.M. Al-Sabagh Y.M. Moustafa A. Hamdy H.M. Killa R.T.M. Ghanem R.E. Morsi 《Egyptian Journal of Petroleum》2018,27(3):403-413
Magnetite nanoparticles (MNPs) were prepared by co-precipitation method and were found to have average size of 5 nm with spherical shape crystalline structure with super-magnetic properties. Commercial polystyrene (PS) was sulfonated through the reaction with freshly prepared acetyl sulfate. Three different degrees of sulfonation, based on the ratio of the acetyl sulfate to polystyrene, were prepared (1:1, 1:3 and 1:5). Nanocomposites of the prepared magnetite nanoparticles 1:3 sulfonated polystyrene were prepared at different magnetite content (1, 5 and 10%). The produced materials were characterized by dynamic light scattering (DLS), transmittance electron microscope (TEM) X-ray diffraction (XRD) and vibrating sample magnetometer (VSM). PS, MNPs and the prepared nanocomposites were investigated as adsorbents for Congo Red (CR). The variables influencing the adsorption capacity, such as solution pH, contact time and the initial dye concentration were systematically investigated. The adsorption for CR by the previous adsorbents show maximum experimental uptake capacity of 26.78, 33.15, 53.35, 64.73, and 76.29 mg/g for PS, MNPs, SPS/MNPs 1%, SPS/MNPs 5% and SPS/MNPs 10%, respectively. The adsorption process was found to follow the pseudo second order kinetic model and fit quite well with Langmuir adsorption isotherm. 相似文献
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《Food Control》2014
Aflatoxin M1 (AFM1) is a hydroxylated metabolite of aflatoxin B1 and its presence in milk is considered to be a potential health risk for humans. Due to the important role of milk in humans, especially in infant nutrition, this study is intended to evaluate the quality of milk consumed on daily basis in South Africa by both rural and urban population in regard to AFM1 contamination. To achieve this, samples were collected from rural subsistence (RSFs) and commercial dairy farms (CDFs) in selected areas of South Africa and samples were extracted using two clean-up procedures, C18 cartridges and immunoaffinity columns (IAC) and analysed using thin layer chromatography (TLC) or by fluorometry (VICAM) (VF) and high pressure liquid chromatography (HPLC) coupled with a fluorescence detector and a coring cell (CoBrA cell) for AFM1 derivatisation. Results obtained showed a frequency of contamination with AFM1 of RSFs milk samples at 22.8% by TLC, 93.9% by VF 86% by HPLC and in CDFs of 17.8% (TLC) 96.5% (VF) and 100% (HPLC). No significant differences were obtained between milk from rural subsistence and commercial farms with mean varying between 0.15 and 0.17 μg kg−1 相似文献
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琥珀酸二(2-乙基丁酯)磺酸钠的合成与性能研究 总被引:1,自引:0,他引:1
研究了采用非外加相转移催化剂在敞开体系中进行反应合成琥珀酸二 ( 2乙基丁酯 )磺酸钠的新方法( )。得到的最佳工艺条件为 :2乙基 1丁醇与顺酐的摩尔比为 2 .2 6∶ 1 ,于 1 30℃条件下酯化反应 1 .5h,得到酯化率为 95%的酯化产物。亚硫酸氢钠与顺酐的摩尔比为 1 .1 0∶ 1 ,加热介质温度为 1 30℃下磺化反应3.2 5h。测定了所得产物的表面活性与应用性能 :表面张力、临界胶束浓度、乳化力和渗透率分别为 3.2 4×1 0 - 2 N/m,3.72× 1 0 - 2 mol/L,1 .2 5min和 9.6 s。与外加相转移催化剂方法 ( )制得的产物进行性能对比 ,结果表明 :两种方法所得产物的主要表面活性和应用性能相近。而方法 ( )比方法 ( )减少了水洗、蒸馏和外加相转移催化剂的过程 ,具有较大的应用前景 相似文献
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以KPS-Na_2S_2O_3为引发体系,水为反应介质,研究了丙烯酸丁酯(BA)与玉米淀粉的接枝共聚合反应规律,用IR、SEM、DSC等手段分析了反应产物的结构。试验结果表明,当淀粉浓度为4%;[BA]为4.20×10~(-1)mol/l;[Na_2S_2O_3]为2.0×10~(-3)mol/l;[KPS]在(3-4)×10~(-3)mol/l范围内;pH=7,60—70℃。反应6h,接枝共聚物的接枝率(G)可达80—90%,接枝效率(E)可达60—70%。 相似文献
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采用自由基溶液聚合法合成了α-甲基丙烯酸混合醇酯(AE)-马来酸酐(MA)-苯乙烯(St)三元共聚物(AMS)降凝剂;考察了AMS的最佳聚合条件及其对中原0#柴油和燕化0#柴油的降滤效果;用GC技术分析了中原0#柴油和燕化0#柴油中正构烷烃碳数的分布;用1HNMR技术表征了AE和AMS的结构。AMS的最佳聚合条件为:n(AE)∶n(MA)∶n(St)=3∶1∶1,时间5h,温度80℃;AMS降凝剂的适宜添加量(占柴油的质量分数)为0.08%,此时中原0#柴油和燕化0#柴油的冷滤点降幅分别为4℃和6℃。对于正构烷烃含量较低、正构烷烃碳数分布较宽且较均匀的柴油,使用AMS降凝剂时,降滤效果较好。 相似文献