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141.
GC-MS与GC-FTIR联合测定C9烃馏分组成 总被引:1,自引:0,他引:1
混合碳九组成复杂,估计为环状烯烃、芳烃、多环烃、烷烃等,目前该产品主要用于生产石油树脂。随着我国乙烯生产能力的不断扩大,其产量也在不断增加,为充分利用碳九资源,研究开拓其新的应用领域非常必要。而此研究的首要条件在于对其组成进行较为全面、准确地分析。传统的分析方法不能对其组成提供详尽的数据资料,直接影响了对碳九进行综合利用研究。GC-MS兼有GC的高效分离能力与MS很好的定性功能,且灵敏度较高,是分析有机混合物十分有效的手段。本文将GC-MS应用于碳九组成的定性分析中。但由于碳九组分中含有较多的同分异构体如三甲苯与二甲苯等,同分异构体的质谱图几乎相同,GC-MS对其不易鉴别,而红外(FTIR)对有机物同分异构体尤其苯系物的异构体具有非常好的鉴别能力。因此本文将GC-MS与GC-FTIR联合使用,对碳九组成进行定性分析,样品定量采用色谱氢火焰检测器峰面积归一化法得到的各组分峰面积相对百分含量,较好地解决了碳九组分的定性定量问题,为开发碳九新的应用领域提供依据。 相似文献
142.
The investigated materials have similar routes of thermal decomposition; i.e. they lose their crystal water first, then at
a higher temperature their structural one. At least the result TiP2O7 goes through a phase change at about 1000 K. The amorphous titanium phosphate lost its crystal and structural water at higher
temperature than those of crystalline forms. Both α- and γ-titanium phosphates and also their transition metal containing
forms have layered structure. In case of α- and γ-forms after the loss of crystal water a phase change occurs which is followed
by the decomposition of the molecule. Various transition metals containing γ-titanium phosphates lose their crystal water
at the same temperature, with the exception of Ni containing ones. The process is finished in this case at temperature 90
K higher than that of the others.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
143.
144.
Norio Tsubokawa Yukio Shirai Hideyo Tsuchida Satoshi Handa 《Journal of polymer science. Part A, Polymer chemistry》1994,32(12):2327-2332
The photografting of polymers onto ultrafine inorganic particles, such as silica and titanium oxide, initiated by azo groups introduced onto these surfaces was investigated. The introduction of azo groups onto the particles was achieved by the reaction of 4,4′-azobis(4-cyanopentanoic acid) with surface isocyanate groups, which were introduced by the treatment with tolylene 2,4-diisocyanate. It was found that the photopolymerization of vinyl monomers, such as methyl methacrylate (MMA), styrene, and N-vinylcarbazole, is initiated by ultrafine particles having azo groups. The corresponding polymers were effectively grafted onto these surfaces through the propagation of the polymer from the surface radicals formed by the photodecomposition of the azo groups: e.g., the percentage of grafting of PMMA and polystyrene onto silica was reached to 112 and 176%, respectively. The percentage of grafting onto silica in the graft polymerization initiated by photodecomposition of surface azo groups was much larger than that initiated by thermal decomposition. Polymer-grafted ultrafine particles thus obtained gave a stable colloidal dispersion in good solvents for the grafted chain. © 1994 John Wiley & Sons, Inc. 相似文献
145.
W. Fleischhacker K. Florkova B. Richter 《Monatshefte für Chemie / Chemical Monthly》1994,125(3):345-353
Summary Following our concept of rather new structural variations in the nitrogen region of morphine alkaloids we describe the first synthesis of N/C-10-bridged tertiary bases. 相似文献
146.
147.
Giampiero Bettinetti Milena Sorrenti Laura Catenacci Franca Ferrari Silvia Rossi Ilaria Salvadeo Paolo Carraro 《Journal of inclusion phenomena and macrocyclic chemistry》2007,57(1-4):329-332
Triacetyl α-cyclodextrin, triacetyl β-cyclodextrin and triacetyl γ-cyclodextrin were tested as possible hydrophobic carriers
to prolong the release of hydrophilic teicoplanin (TCP). Physical–chemical characterization of individual components, drug-carrier
physical mixtures at 0.5, 0.67 and 0.75 mass fraction of carrier, and the respective interaction products by kneading or evaporative
crystallization under microwave irradiation was carried out using differential scanning calorimetry (DSC) and thermogravimetric
analysis (TGA). In vitro drug release in pH 7.4 phosphate buffer at 37 °C was determined by intrinsic dissolution rate (IDR)
measurements on non disintegrating compressed discs. Solid-state interactions of TCP with triacetyl α-cyclodextrin by evaporative
crystallization and kneading and with triacetyl β-cyclodextrin by evaporative crystallization (probably resulting in carrier
amorphization) were demonstrated. The role of carrier hydrophobicity, carrier mass fraction and preparation method of solid
drug-carrier combinations on solid-state drug-carrier interactions and slowing down of TCP release was assessed. Modulation
of drug release can be achieved using TCP-triacetyl γ-cyclodextrin combinations at 0.5 mass fraction of carrier. 相似文献
148.
环境中排放的重金属离子Cu!对水生和陆生生物有强的毒害性。饮用水中Cu!的浓度高于1.0mg·L-1时,将会导致人畜得血色沉着病和胃肠粘膜病[1]。Cu!无法进行生物降解,除去废水中Cu!的常见方法有离子交换、置换、化学沉淀等[2],然而这些方法需要消耗大量的化学试剂,成本高。近来,研 相似文献
149.
150.
首次研究了铝铁合金溴化物的合成及其对直链烷烃异构化反应的催化作用,讨论了正戊烷的异构化反应,得到其动力学方程为1nC/C_0=-0.50t,表观活化能为26.3 kJ/moJ,测定了正己烷、正庚烷、正辛烷在不同溶剂中、不同温度下催化异构化反应的动力学曲线,为铝铁合金溴化物的工业应用提供了理论依据。 相似文献