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用开管毛细管柱的气相色谱和质谱法研究芬兰浮油松香中树脂酸的组成。在一个涂有1.4—丁二酸丁二醇酯的柱子上,浮油松香样品中已知的16个树脂酸都能得到很好的分离,并且能用质谱加以记录。气相色谱—质谱法证实了所有的树脂酸都是海松酸型和枞酸型的。在相应的粗浮油中有8个酸没有被检出,很明显它们是在蒸馏工艺过程中形成的。8,15—海松二烯—18—酸和8,15—异海松二烯—18—酸在松香中是存在的,而不存在于粗浮油中,这就表明在浮油蒸馏过程中海松酸型酸也发生了多样的异构作用。另外,在蒸馏过程中形成了三个二氢枞酸和具有同一质谱峰的两个酸,据推测是7,9(11)—枞二烯—18—酸的立体异构体。 相似文献
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《高校化学工程学报》2016,(1)
以再生FCC废触媒负载镍为催化剂进行松脂加氢反应,采用GC-MS对催化加氢产物进行分析,并利用改变搅拌转速和催化剂粒径的方法,消除松脂加氢过程中的内外扩散影响。结果表明,再生FCC废触媒负载镍催化松脂加氢反应的最优条件为:温度468 K、压力5 MPa、催化剂用量5%(wt)和反应时间为60 min;搅拌转速为400 r?min?1时,基本消除了外扩散影响;催化剂的粒径小于100μm时,消除了内扩散的影响;反应产物鉴定出14种化合物,其中二氢海松酸和二氢异海松酸含量分别为4.75%和5.84%,二氢枞酸同分异构体分别是13β-8(14)-Abietenoic acid,13-Abietenoic acid,13β-7-Abietenoic acid,8-Abietenoic acid,13β-8-Abietenoic acid,8(14)-Abietenoic acid,含量为64.98%;脱氢枞酸含量为8.06%;四氢枞酸是8α-13β-Abietanoic acid,含量为13.89%;枞酸和新枞酸的含量分别为1.20%和0.34%。 相似文献
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综述了国内外歧化松香生产、应用和松香催化歧化反应的研究进展。着重从生产工艺、产品用途和相关基础理论研究方面进行了评价和比较,指出今后松香催化歧化反应的研究主要方向是明晰催化反应机理,进而制备出高活性和高选择性的非贵金属催化剂,开发新工艺生产高含量去氢枞酸的歧化松香,寻找新的去氢枞酸的分离方法。 相似文献
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以松香为原料、改性Pd/C为催化剂、200#油为溶剂及N2为保护气,进行松香催化歧化反应集总动力学的研究。在消除内外扩散影响的条件下,在线跟踪48315~53315 K的反应产物并用毛细管柱气相色谱法测定反应体系组成随时间的变化关系。根据松香歧化反应机理和特点,借鉴集总思想和方法,按结构族组成和动力学相近原则划分该复杂反应体系的集总组分,构建了Pd/C上松香歧化集总反应网络,建立了枞酸型树脂酸、海松酸型树脂酸、氢化枞酸型树脂酸、氢化海松酸型树脂酸和脱氢枞酸五集总动力学模型;采用Levenberg-Marquart法,以Matlab编程和SPSS数理统计软件估算了模型参数,得到枞酸型树脂酸脱氢、加氢,海松酸型树脂酸加氢反应过程的活化能分别为11139 kJ·mol-1、10876 kJ·mol-1、9735 kJ·mol-1,结果表明,所建动力学模型与实验数据吻合良好,并能预测反应在54315 K的集总组分浓度分布。 相似文献
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用GC/MS和FTIR技术结合气相色谱外标定量分析方法,对神府煤甲醇萃取物进行了定性和定量分析,讨论了神府煤甲醇萃取物的化学组成及其结构特征.结果显示,神府煤甲醇萃取物的GC/MS可测组分主要由多环芳烃和含氧化合物组成,其中芳烃以2~3环的烷基取代稠环芳烃为主,含氧化合物中以酮类和酯类化合物居多;结果还检测到种类较多的含氮化合物和少量的含硫、磷、氯的化合物.GC/MS不可测组分的IR分析显示,其中主要官能团有各类羟基、羰基、芳环和亚甲基、甲基等,表明其中可能存在分子量较大的稠环芳香族或其酚、酸、酮、酯类及烷基衍生物的化合物. 相似文献
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大庆乙烯副产C9馏分的GC及GC/MS分析 总被引:1,自引:0,他引:1
本文通过对大庆乙烯副产的C9馏份油进行GC及GC/MS分析确定了该C9的组成。共检出38种物质,其中不饱和烃约为46.7%。其结果与C9馏份的实沸点切割、溴值测定及^1H-NMR分析结果相吻。 相似文献
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Double-bond localization in heneicosapentaenoic acid by a gas chromatography/mass spectrometry (GC/MS) method 总被引:1,自引:1,他引:1
Double-bond locations in heneicosapentaenoic acid from eel lipids were determined by a method involving gas chromatography/mass
spectrometry (GC/MS). The methyl esters of the pentaenoate fraction were first partially reduced with hydrazine. The resultingcis-monoenoates were then methylthiolated, and the resultant adducts were analyzed by GC/MS. The key fragmentation ions generated
by the cleavage between the methylthio-substituted carbons were used to ascertain the original double-bond positions in the
native fatty acid esters. Based on mass spectral evidence, the acid was identified as all-cis-6,9,12,15,18-heneicosapentaenoic acid. 相似文献
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超临界CO_2萃取铁观音茶叶香气成分 总被引:3,自引:0,他引:3
分别采用索氏萃取(SE)、同时蒸馏萃取(SDE)和超临界CO2萃取(SFE)方法提取铁观音的香气成分。用GC/MS分析比较了萃取物中香气成分的组成及质量分数。SDE获得了最多的香气组分,而SFE得到的主要香气成分质量分数和萃取率最高。进一步考察了SFE的压力、温度及夹带剂对主要香气成分的萃取率及质量分数的影响,结果表明随着压力升高香气成分的萃取率及质量分数均升高。而当温度和夹带剂中乙醇质量比为45℃和5%时,总香气成分的萃取率最高,且主要香气成分的质量分数比未添加夹带剂时提高达几十倍,与SFE所得萃取物在香烟中品香评吸的结论完全吻合。 相似文献
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将国内外5种(国外1种,国内4种)低焦油烤烟型卷烟烟丝经同时蒸馏萃取、GC、GC/MS分析测试,对低焦油烤烟型卷烟烟丝29种中性香味成分进行了分析研究。国内外卷烟烟丝的常规化学成分也进行了测试比较。结果发现,国产烤烟型卷烟挥发性、半挥发性中性成分总量、酮类成分总量、醇类成分总量比国外烤烟型卷烟低,醛类成分总量、酯类成分总量比国外高。4种国产烤烟型卷烟烟丝重要中性香味成分中均比国外烤烟型卷烟低10%以上的有:苯乙醛、糠醇、苯甲醇、六氢金合欢基丙酮和2-甲氧基4-乙烯基苯酚;均高于10%的有:糠醛、亚麻酸甲酯等。 相似文献
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Jan Mosio-Mosiewski Marek Warzala Ireneusz Morawski Tadeusz Dobrzanski 《Fuel Processing Technology》2007
The thermal cracking and catalytic cracking processes of low-density polyethylene were studied in a closed autoclave. The compositions of gaseous and liquid products were analysed by means of GC/FID and GS/MS chromatographic methods. The fractional composition of liquid products was found by distillation. Increased temperature of PE depolymerisation process increases the production of gaseous products and low-boiling liquid compounds; more aromatic hydrocarbons are formed instead of alkenes. When a lower temperature and longer time are adopted for the process to reach the assumed conversion, more straight chained hydrocarbons are produced. The acidic aluminosilicate catalyst yields more low-boiling liquid fractions, more isoalkanes and more aromatics. The neutral alumina is favourable for the production of alkenes and vacuum gas oil fraction in comparison to a non-catalytic process. The Ni–Mo/Al2O3 catalyst is efficient in hydrogenation of depolymerisation products. The reaction products contain only saturated compounds then and no aromatics are formed. 相似文献
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Furan fatty acids (F‐acids) are a class of natural antioxidants with a furan moiety in the acyl chain. These minor fatty acids have been reported to occur with high proportions in the cholesteryl ester fraction of fish livers. Here we present a method for the direct analysis of intact cholesteryl esters with F‐acids and other fatty acids in cod liver lipids. For this purpose, the cholesteryl ester fraction was isolated by solid phase extraction (SPE) and subsequently analyzed by gas chromatography with mass spectrometry (GC/MS) using a cool‐on‐column inlet. Pentadecanoic acid esterified with cholesterol was used as an internal standard. GC/MS spectra of F‐acid cholesteryl esters featured the molecular ion along with characteristic fragment ions for both the cholesterol and the F‐acid moiety. All investigated cod liver samples (n = 8) showed cholesteryl esters of F‐acids and, to a lower degree, of conventional fatty acids. By means of GC/MS‐SIM up to ten F‐acid cholesteryl esters could be determined in the samples. The concentrations of cholesteryl esters with conventional fatty acids amounted to 78–140 mg/100 g lipids (mean 97 mg/100 g lipids), while F‐acid cholesteryl esters were present at 47–270 mg/100 g lipids (mean 130 mg/100 g lipids). 相似文献
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分子蒸馏处理香料烟浸膏制备烟用香料 总被引:1,自引:0,他引:1
为了更好地精制富集烟草特征香味成分,采用分子蒸馏技术对溶剂法制备的香料烟浸膏进行分离,并对馏分进行GC/MS分析。GC/MS结果显示,在不同温度段,香料烟浸膏致香成分得到富集,特别是40~60℃馏分中香料烟重要香味成分茄酮达到了17%。评吸结果显示:原香料烟提取物能增香及提高香气质,但残留明显。经分子蒸馏处理后,40℃以下馏分香气质较好,香气量不足,余味舒适;40~60℃馏分香气质好,丰富烟香,口腔舒适,改善烟气状态;60~80℃馏分增加香气量,舌面口腔有残留;蒸余物则对烟气增香无明显影响。 相似文献