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基于气相离子迁移色谱分析不同贮藏时期蓝莓的挥发性化合物变化
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作者 田芸 孙海燕 +3 位作者 朱旋 郝丹青 秦公伟 党娅 《食品研究与开发》 CAS 2024年第24期168-175,共8页
以蓝莓为研究对象,通过气相离子迁移色谱(gas chromatography‐ion mobility spectrometry,GC‐IMS)技术采集蓝莓贮藏过程中挥发性化合物(volatile compounds,VOCs)的变化,探究不同贮藏时期蓝莓的关键气味化合物。该研究采用壳聚糖涂膜... 以蓝莓为研究对象,通过气相离子迁移色谱(gas chromatography‐ion mobility spectrometry,GC‐IMS)技术采集蓝莓贮藏过程中挥发性化合物(volatile compounds,VOCs)的变化,探究不同贮藏时期蓝莓的关键气味化合物。该研究采用壳聚糖涂膜+紫外灯照射处理蓝莓并分别在蓝莓新鲜、萎蔫、腐败时测定其VOCs,分析其指纹谱图,对蓝莓VOCs进行主成分分析(principal components analysis,PCA)及正交偏最小二乘判别分析(orthogonal partial least squares discriminant analysis,OPLS‐DA)。结果表明,蓝莓中的挥发性化合物主要有酯类、醇类、醛类、酸类、酮类及萜烯类化合物;(E)‐2‐己烯‐1‐醇、丁醛等物质在新鲜蓝莓中含量较高,丁酸、异戊酸主要存在于蓝莓萎蔫阶段,腐败时乙酸乙酯、3‐戊酮等物质浓度上升,反映了蓝莓贮藏期间VOCs的变化情况。使用GC‐IMS检测得到的数据进行主成分分析和正交偏最小二乘法判别分析,由此可知,不同时期蓝莓的挥发性气味具有明显区别。 展开更多
关键词 蓝莓 离子迁移色谱(gc‐IMS) 化学计量法 贮藏 挥发性化合物
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气相质谱法检测动物源性食品中三聚氰胺的残留 被引量:4
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作者 阮祥春 曾明华 张莉 《安徽农业大学学报》 CAS CSCD 北大核心 2009年第3期464-468,共5页
为了检测动物源性食品中三聚氰胺的残留,建立气相质谱(GC/MS)方法,并对样品包括鲜乳、鸡蛋、鸡肉和猪肉进行三聚氰胺的残留检测。结果显示,建立的GC/MS方法在线性范围内,回收率高、精密度好,达到国家最低检测限的要求。
关键词 质谱(gc/MS) 动物源性食品 三聚氰胺 残留
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气相色谱/负化学源质谱法测定蜂蜜中氯霉素的残留量 被引量:5
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作者 陈朝方 罗玉玮 +1 位作者 郑帆 瞿进文 《理化检验(化学分册)》 CAS CSCD 北大核心 2004年第10期571-573,共3页
建立气相色谱/负化学源质谱(GC/NCIMS)测定蜂蜜中氯霉素残留量的方法。蜂蜜中残留的氯霉素经液-液萃取、固相萃取提取、净化和硅烷化衍生后,进样分析。负化学源质谱采用选择离子模式进行检测,特征离子为m/z=466,468,外标法定量。结... 建立气相色谱/负化学源质谱(GC/NCIMS)测定蜂蜜中氯霉素残留量的方法。蜂蜜中残留的氯霉素经液-液萃取、固相萃取提取、净化和硅烷化衍生后,进样分析。负化学源质谱采用选择离子模式进行检测,特征离子为m/z=466,468,外标法定量。结果表明,样品中氯霉素浓度为1.0-20μg·kg-1时,工作曲线的线性良好(r=0.9989),回收率为71%-93%,检出限为0.5μg·kg-1。 展开更多
关键词 /负化学源质谱(gc/NCIMS) 残留氯霉素 蜂蜜
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气相检测中微量注射器的清洁方法探讨
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作者 梁毅 魏默涵 《江苏科技信息》 2014年第6期52-53,共2页
文章通过设计实验,探讨洗净微量注射器所需要的溶剂与次数,建立相关清洗方法,为气相工作者提供参考。
关键词 (gc) 微量注射器 清洁方法
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调控鼠骨髓间质干细胞增殖的中药龟板化学成分的GC-MS测定 被引量:2
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作者 王春燕 曾和平 陈薇 《华南师范大学学报(自然科学版)》 CAS 2007年第1期89-97,共9页
促进鼠骨髓间质干细胞(rMSCs)增殖分化的中药龟板提取物有效部位,经硅胶柱层析,用石油醚-乙酸乙酯作洗脱剂,梯度洗脱,得到16个样品;用GC-MS技术测定了它们的化学组成;采用MTT法研究了它们对MSCs的增殖作用,结果显示,Ts-2,Ts-3,Ts-11,Ts-... 促进鼠骨髓间质干细胞(rMSCs)增殖分化的中药龟板提取物有效部位,经硅胶柱层析,用石油醚-乙酸乙酯作洗脱剂,梯度洗脱,得到16个样品;用GC-MS技术测定了它们的化学组成;采用MTT法研究了它们对MSCs的增殖作用,结果显示,Ts-2,Ts-3,Ts-11,Ts-12,Ts-16能促进MSCs的增殖(P<0.05);Ts-4对MSCs具有抑制作用,其它样品对MSCs的增殖作用不显著(P>0.05),不具统计学意义. 展开更多
关键词 龟板有效成分(PTEC) 柱层析 质谱联用(gc—MS) 鼠骨髓间充质干细胞(MSCs) MTT法
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GC-MS Analysis of Essential oil and n-Hexane Extract from Moso Bamboo 被引量:2
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作者 刘志明 任海青 《Agricultural Science & Technology》 CAS 2012年第5期993-996,共4页
[Objective] This study aimed to analyze the chemical composition and yield of essential oil and n-hexane extract from moso bamboo to find active compounds with potential value. [Method] Essential oil and n-hexane extr... [Objective] This study aimed to analyze the chemical composition and yield of essential oil and n-hexane extract from moso bamboo to find active compounds with potential value. [Method] Essential oil and n-hexane extract were respectively extracted from moso bamboo of four different ages by using hydrodistillation and ultrasonic-assisted extraction with n-hexane, and analyzed with gas chromatography/mass spectrometry (GC/MS). [Result] The results show that cedrol (46.39%) is the first principal volatile component in essential oil of the middle stem of 7-year old moso bamboo; dibutyl phthalate (59.46%) is the first principal volatile component in n-hexane extract of the middle stem of 3-year old moso bamboo; yield of n-hexane extract is higher than that of essential oil from moso bamboo. [Conclusion] Cedrol is an active compound with potential value. 展开更多
关键词 Moso bamboo HYDRODISTILLATION Ultrasonic assistance n-hexane extract Gas chromatography/mass spectrometry gc/MS)
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不同提取工艺下蜂胶醇提物的GC-MS分析 被引量:6
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作者 蔡君 谭群 +1 位作者 晏家瑛 万佳 《现代食品科技》 EI CAS 2010年第5期544-550,553,共8页
用超临界CO2萃取+残渣醇提法提取毛胶,获得CO2提取物和CO2残渣醇提物,用GC-MS法分析两种提取物中醇提物化学成分,并与传统工艺醇提物比较,结果表明:湖南蜂胶的两种提取物分别有189个和200个成分,鉴定出其中88个和78个成分,与传统醇提物... 用超临界CO2萃取+残渣醇提法提取毛胶,获得CO2提取物和CO2残渣醇提物,用GC-MS法分析两种提取物中醇提物化学成分,并与传统工艺醇提物比较,结果表明:湖南蜂胶的两种提取物分别有189个和200个成分,鉴定出其中88个和78个成分,与传统醇提物(仅有144个成分,鉴定出63个成分)相比均含有更多种类的烯、萜、醇、酚、酸、酯类和黄酮类等化学成分,醇提物总得率更高;黄酮类成分在残渣醇提物中含量更高,在CO2提取物的醇提物中为主要成分,在压力35MPa,温度32℃等超临界萃取条件下对蜂胶中部分黄酮类化合物的选择性较好。为蜂胶中更多活性物的深入研究和广泛开发应用提供实验依据。 展开更多
关键词 蜂胶 提取物 醇提物 色普质(gc—MS)
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GC/MS定量检测皂角种子不同部位脂肪酸组成
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作者 田冬梅 于畅游 娄志红 《中国林副特产》 2017年第4期9-13,共5页
采用GC/MS法对皂角种子不同组织部位脂肪酸进行分析。通过质谱数据库检索和标准品对照鉴定出16种脂肪酸,分别为:肉蔻酸,十五烷酸,棕榈酸,棕榈油酸,硬脂酸,反油酸,油酸,亚油酸,花生酸,二十碳一烯酸,α-亚油酸,二十一烷酸,二十碳二烯酸,... 采用GC/MS法对皂角种子不同组织部位脂肪酸进行分析。通过质谱数据库检索和标准品对照鉴定出16种脂肪酸,分别为:肉蔻酸,十五烷酸,棕榈酸,棕榈油酸,硬脂酸,反油酸,油酸,亚油酸,花生酸,二十碳一烯酸,α-亚油酸,二十一烷酸,二十碳二烯酸,二十二烷酸,二十三烷酸,二十四烷酸。其中子叶中含有15种脂肪酸,种皮中含有7种脂肪酸,有6种脂肪酸同时存在子叶和种皮中,分别为:棕榈酸,棕榈油酸,硬脂酸,油酸,亚油酸,α-亚油酸,这些脂肪酸主要显著积累在子叶中,是种皮的100~200倍。此外,将皂角种子与其他油料种子进行比较分析,最终发现棕榈酸,硬脂酸和亚油酸均高于大豆,芝麻和葵花籽,说明皂角种子同样具有重要的营养价值。实验为皂角种子的综合开发利用提供科学依据。 展开更多
关键词 质谱联用(gc/MS) 皂角 种皮和子叶 脂肪酸
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Composition of Trans-anethol and Other Aromatic Volatiles in Anisated Alcoholic Beverages by Head-Space GC-MS Chromatography
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作者 Marie Gerogiannaki Theophilos Masouras 《Journal of Environmental Science and Engineering(A)》 2015年第1期36-39,共4页
Aniseed distillates, like ouzo in Greece, raki in Turkey, pastis in France, and arak in Syria, are very popular in Mediterranean countries. This flavoured alcoholic beverage is produced by extraction and distillation ... Aniseed distillates, like ouzo in Greece, raki in Turkey, pastis in France, and arak in Syria, are very popular in Mediterranean countries. This flavoured alcoholic beverage is produced by extraction and distillation of fermented grape pomaces with herbal seeds from aromatic plants like Pimpinella anisum L., Foeniculum vulgate, Illicium verum and other plants which are also characterized by the presence of congeners which arise during fermentation process. Trans-anethol and its isomer cis-anethol are the main volatiles and are responsible for aroma properties of these traditional aniseed distillates. The aim of this research work was to find the concentration of special aromatic agent, trans-anethol and cis-anethol and also the major aromatic substances which are responsible for the aromatic quality. The majority of their identified components are isolated by extraction and distillation from different commercial brands and homemade samples. The constituents were identified by GC-MS (gas chromatography-mass spectometry) in this traditional spirit. The major constituents in distilled ouzo extract were also trans-anethol. 展开更多
关键词 Trans-anethol anis distillates ouzo.
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沙棘添加对乳酸菌发酵牛乳风味和消费者接受度的影响 被引量:6
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作者 葛晓佳 唐楠煜 +5 位作者 杨瑞 赵小淦 刘再美 许丹玲 刘玉肖 李伟 《食品工业科技》 CAS 北大核心 2022年第3期97-105,共9页
本研究目的是探究添加沙棘(5%,v/v)对发酵乳风味和消费者接受度的影响。选取本实验室前期从新疆老酸奶、西藏开菲尔颗粒等样品中筛选到的8株乳酸菌进行原味发酵乳和沙棘发酵乳的制备。通过电子鼻(Electronic-nose,E-nose)和电子舌(Elect... 本研究目的是探究添加沙棘(5%,v/v)对发酵乳风味和消费者接受度的影响。选取本实验室前期从新疆老酸奶、西藏开菲尔颗粒等样品中筛选到的8株乳酸菌进行原味发酵乳和沙棘发酵乳的制备。通过电子鼻(Electronic-nose,E-nose)和电子舌(Electronic-tongue,E-tongue)技术,采用模糊数学综合评定法对不同发酵乳的消费者接受度作出评价,进一步利用顶空固相微萃取气质联用技术(Head space-solid phase microextraction-gas chromatography/mass,HS-SPME-GC/MS)对原味发酵乳和沙棘发酵乳中的风味物质组成进行分析。结果显示添加沙棘(5%,v/v)可以对发酵乳的风味产生显著影响,主要体现为香气的增加和不良气味的减弱,在滋味上表现为苦味、鲜味和丰富度的减少。GC/MS结果表明沙棘发酵乳中含有更高浓度的酯类和醇类化合物,是其中水果香气、发酵香气和浓郁花香的主要贡献者;在所选取的8株乳酸菌中,来源于泡菜的戊糖乳杆菌Z-14(Lactobacillus pentosus Z-14),其沙棘发酵乳的综合评定结果最优,且具有最高的消费者接受度。 展开更多
关键词 沙棘发酵乳 风味 电子鼻 电子舌 串联质谱(gc/MS)
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不同矿山化学药剂对水体COD贡献和影响的试验研究
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作者 李伟新 《安徽农学通报》 2012年第12期51-53,共3页
矿山选矿药剂的使用已经引起了严重的水体污染,为了可持续利用矿区水资源,选择了常见的5种浮选药剂和3种起泡剂进行了其对水体化学需氧量(COD)贡献和影响的试验研究。研究结果表明:不同浓度范围的乙黄原酸盐(乙黄)、丁黄原酸盐(丁黄)、... 矿山选矿药剂的使用已经引起了严重的水体污染,为了可持续利用矿区水资源,选择了常见的5种浮选药剂和3种起泡剂进行了其对水体化学需氧量(COD)贡献和影响的试验研究。研究结果表明:不同浓度范围的乙黄原酸盐(乙黄)、丁黄原酸盐(丁黄)、聚丙烯酰胺(PAM)、乙硫氮、DS对水体COD的贡献不一样,并且同一种浮选药剂在不同浓度条件下对应的COD并不呈现线性关系。总体来看,5种药剂中丁黄对COD贡献最大,而乙硫氮对COD贡献最小。不同来源起泡剂对水体COD的贡献有较大差异,总体来看GY2#要比SD2#及ZZ2#的COD贡献大。起泡剂的GC-MS仪器分析结果显示起泡剂中多环化合物或者杂环化合物占的比例越大,其对废水COD贡献越多,因此研制以直链状为主要成分的"环保型"起泡剂显得尤为迫切。 展开更多
关键词 浮选药剂 起泡剂 化学需氧量(COD) 质谱连用仪(gc—MS)
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Chemical composition of the essential oil from Rabdosia lophanthoides 被引量:1
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作者 石浩 邹建凯 潘远江 《Journal of Zhejiang University Science》 CSCD 2002年第3期283-287,共5页
Gas chromatography/mass spectrometry (GC MS) of the essential oil from the aerial parts of Rabdosia lophanthoides resulted in the identification of 108 compounds representing 78.120% of the oil. Hydro distillati... Gas chromatography/mass spectrometry (GC MS) of the essential oil from the aerial parts of Rabdosia lophanthoides resulted in the identification of 108 compounds representing 78.120% of the oil. Hydro distillation of Rabdosia lophanthoides yielded a pale yellow oil. The compounds identified and their relative proportions are listed in Table 1 according to their order of elution on an HP 5MS capillary column. . 展开更多
关键词 Rabdosia lophanthoides Composition of essential oil gc MS analysis Ladentification of 108 compounds
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Anti-inflammatory and Chemical Composition of Two Plants Family Asteraceae Growing in Saudi Arabia
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作者 Eman Elsharkawy Mona Alshathly Mohamed Helal 《Journal of Chemistry and Chemical Engineering》 2014年第2期157-162,共6页
The study was designed to investigate the anti-inflammatory and composition of essential oil of two plant family Asteraceae, Achillea fragrantissima and Lactuca serriola growing under dry desert condition. The anti-in... The study was designed to investigate the anti-inflammatory and composition of essential oil of two plant family Asteraceae, Achillea fragrantissima and Lactuca serriola growing under dry desert condition. The anti-inflammatory effect of volatile oil extracted by hydrodistillation of plants was studied using carrageenan induced paw edema. Essential oil (100 mg/kg) and (200 mg/kg) were tested the two plant show high inhibition after 4 h, concentration (200 mg/kg) show high inhibition than (100 mg/kg) after 4 h. Sesqui sabinene hydrate, Azuline and u-Bisabolol are the main constituents of the volatile oil were investigated by capillary GC (gas chromatography) and GC-MS (gas chromatography-mass spectrometry). The discussion shows the role of chemical compound azulene in inflammatory inhibition. 展开更多
关键词 Achillea fragrantissima Lactuca serriola ANTI-INFLAMMATORY azulene.
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Synthesis of Novel Electron Donors and Their Application to Propylene Polymerization 被引量:1
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作者 GUO Jintang HU Guang CHEN Zhikun 《Transactions of Tianjin University》 EI CAS 2012年第1期8-14,共7页
A series of electron donors,including 1,1-cyclopentanecarboxylic acid diethyl ester (CPCADEE),1,1cyclopentanedimethanol acetic diester (CPDMAD),1,1-biethoxymethyl pentane (BEMP),2,2-diethyl diethylmalonate (DEDEM)and ... A series of electron donors,including 1,1-cyclopentanecarboxylic acid diethyl ester (CPCADEE),1,1cyclopentanedimethanol acetic diester (CPDMAD),1,1-biethoxymethyl pentane (BEMP),2,2-diethyl diethylmalonate (DEDEM)and 2,2-diethyl-1,3-propanediol acetic diester (DEPDADE),were synthesized by diethyl malonate (DEM).The purities and structures of the above products were characterized by gas chromatography (GC) and gas chromatography-mass spectrometer (GC-MS),respectively.Furthermore,the possible optimal three-dimensional structures of these donors were simulated by means of Gaussian 03 and Chem 3D.Then these electron donors were coordinated with tetrachloro titanium (TiCl 4) and chloride magnesium (MgCl 2)to obtain the catalysts for the polymerization of propylene.The catalytic activities and properties of polypropylene are greatly improved by adding external donor(ED) when CPCADEE or DEPDADE is used as internal donor(ID).However,when BEMP was used as ID,the highest catalytic activity is obtained without adding ED,which can reduce production costs and simplify catalytic synthesis.The experiments indicate that BEMP has the shortest distance of oxygen atoms and the highest electronegativity. 展开更多
关键词 electron donor structural simulation propylene polymerization 1 1-biethoxymethyl pentane
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Study on the basic nitrogen compounds from coal-derived oil 被引量:4
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作者 Xiao-hui GU Xue-feng MAO Yuan ZHAO Wen-bo LI Xiao-jing ZHANG 《Journal of Coal Science & Engineering(China)》 2013年第1期83-89,共7页
The distillation range analysis and elemental analysis of fractioned direct liquefied oil were conducted. Each fraction of liquefied oil contains some nitrogen compounds. Using the acid extraction method and gas chrom... The distillation range analysis and elemental analysis of fractioned direct liquefied oil were conducted. Each fraction of liquefied oil contains some nitrogen compounds. Using the acid extraction method and gas chromatography/mass spectrometry (GC-MS), the basic nitrogen compounds have been separated and identified. Compared with the nitrogen content of the liquefied oil before and after separation, the basic nitrogen compounds account for more than half of all nitrogen compounds. The basic nitrogen compounds in the light liquefied oil are easily separated, and contain more types of basic nitrogen compounds. The results also show that there are many basic nitrogen compounds in liquefied oil, such as pyrrole, aniline, pyridine, quinoline and so on. However, there are fewer other types of basic nitrogen compounds. 展开更多
关键词 liquefied oil SEPARATION gc-MS nitrogen compounds coal-derived oil
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Study of oxidization of coal–pitch by O_3 被引量:2
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作者 Wang Yaoling Chen Sishun +1 位作者 Ding Mingjie Xu Zhan 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2016年第4期677-681,共5页
For the purpose of obtaining small molecular and oxygen-containing aromatic compounds, taking a toluene-extracted coal pitch as the research object, the oxidation of coal-pitch by ozone (03) in formic acid was studi... For the purpose of obtaining small molecular and oxygen-containing aromatic compounds, taking a toluene-extracted coal pitch as the research object, the oxidation of coal-pitch by ozone (03) in formic acid was studied. The coal-pitch sample and the oxidized pitch residue were characterized by elementary analysis and Fourier transform infrared spectroscopy (FTIR), while the small molecular products were analyzed by a gas chromatography-mass spectrometer (GC-MS). The results show that the highest oxygen content of oxidized coal pitch had been acquired at a reaction temperature of 50℃C, an 03 flow rate of 6300 mg/h and a reaction time of 4 h. Quite a lot of hydroxyls and carbonyls were introduced into the structure of the oxidized coal-pitch, while the small molecules produced mainly involve nonpolar aro- matic compounds, aromatic anhydride and quinone compounds. It is speculated that the mechanism is direct electrophilic oxidation in which the molecules of 03 directly attack the aromatic ring at its carbon atoms with high electron density, and then generate hydroxyl or carbonyl until the aromatic ring cracks. This study shows that 03 can make the fused aromatic ring of coal-pitch become oxidized and depoly- merized, and hence the ozonization of coal-pitch can be a potential method for obtaining oxygen- containing aromatic compounds. 展开更多
关键词 Study Coal-pitch Ozone oxidation Depolymerization
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Insight of unresolved complex mixtures of saturated hydrocarbons in heavy oil via GC×GC-TOFMS analysis
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作者 WANG HuiTong ZHANG ShuiChang +5 位作者 WENG Na WEI XiaoFang ZHU GuangYou YU Han BI LiNa MA WenLing 《Science China Chemistry》 SCIE EI CAS 2013年第2期262-270,共9页
The saturated hydrocarbon fraction of a heavily biodegraded crude oil from Liaohe oilfield was analyzed by using comprehensive two-dimensional gas chromatography coupled with time-of-flight mass spectrometry (GC×... The saturated hydrocarbon fraction of a heavily biodegraded crude oil from Liaohe oilfield was analyzed by using comprehensive two-dimensional gas chromatography coupled with time-of-flight mass spectrometry (GC×GC-TOFMS). The "humps", which was termed as unresolved complex mixtures (UCMs) in conventional gas chromatographic analysis, was separated for identification of the individual compound. Main compounds of UCMs were identified according to the combined information of characteristics of GC×GC chromatogram and time-of-flight mass spectra. It's found that UCMs are mainly composed of great number of ring compounds with extremely low concentration. The ring compounds are separated according to their boiling point diversity in the first dimension column, then to their polarity or ring number variety in the second dimension column. In the sample there are two groups of UCMs, i.e., the first group compounds with boiling point lower that of C24 and the second group compounds with boiling point higher than that of C24. The first group of UCMs mainly consists of monocyclic, bicyclic and tricyclic ring compounds. The first group of UCMs is mainly composed of saturated hydrocarbons, in which the percentage of ring compounds with signal-to-noise ratio above 100 is about 75% of the total quantity of saturated hydrocarbon, while its mass is over 80% of the total saturated hydrocarbon. The second group of UCMs is mainly composed of tetracyclic and pentacyclic ring compounds, in which the percentage of UCM compounds with signal-to-noise ratio over 100 is about 17% of the total quantity of saturated hydrocarbon, and its mass is about 0.5% of the total saturated hydrocarbon. The results of this study are helpful for heavy oil developing and genesis mechanism understanding. 展开更多
关键词 comprehensive two-dimensional chromatography time-of-flight mass spectrometry heavy oil biodegradable crude oil saturated hydrocarbons UCM
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A new analytical method for quantifying of sterane and hopane biomarkers 被引量:1
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作者 WANG HuiTong ZHANG ShuiChang +4 位作者 WENG Na ZHANG Bin WEI XiaoFang YU Han WEI CaiYun 《Science China Earth Sciences》 SCIE EI CAS 2014年第8期1713-1722,共10页
An analytical method for quantifying biomarker compounds of the sterane and the hopane existing in saturated hydrocarbons has been established by using comprehensive two-dimensional gas chromatography-flame ionization... An analytical method for quantifying biomarker compounds of the sterane and the hopane existing in saturated hydrocarbons has been established by using comprehensive two-dimensional gas chromatography-flame ionization detector(GC×GC-FID) with optimized operating parameters. The new method achieves the quantification by using a GC×GC-FID system which is able to completely separate steranes from hopanes. The data obtained by the new method are of good repeatability and reliability. Compared with the original data, the relative standard deviations(RSDs) of 12 reference compounds are less than 5%. The RSDs of the quantitative results of the biomarkers based on seven separate analyses are also less than 5%. Compared with the traditional method of gas chromatography-mass spectrometry(GC-MS), the new method has a number of advantages, such as common internal standards(ISs), high resolution, no co-eluting peak, and no interference caused by diagnostic ion peaks. The new method provides petroleum geologists with an effective and scientific means in future researches. 展开更多
关键词 comprehensive two-dimensional gas chromatography gcxgc flame ionization detector (FID) time-of.flight massspectrometry (TOFMS) saturated hydrocarbon biomarker compounds quantification STERANE HOPANE
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Organic composition of gasoline and its potential effects on air pollution in North China 被引量:11
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作者 Guiqian Tang Jie Sun +4 位作者 Fangkun Wu Yang Sun Xiaowan Zhu Yejun Geng Yuesi Wang 《Science China Chemistry》 SCIE EI CAS CSCD 2015年第9期1416-1425,共10页
When gasoline is burned to power an automotive engine, a portion of the fuel remains unburned or is partially burned and leaves the engine as hydrocarbon and oxygenated compounds. In addition, a small portion of the f... When gasoline is burned to power an automotive engine, a portion of the fuel remains unburned or is partially burned and leaves the engine as hydrocarbon and oxygenated compounds. In addition, a small portion of the fuel can escape the vehicle through evaporation. Changes in alkanes, olefins and aromatics each affect emissions differently, which could complicate control strategies for air pollution. In this study, we collected 31 gasoline samples over five provinces and cities(Beijing, Tianjin, Hebei, Shandong, and Shaanxi) in North China between 2012 and 2013. The organic composition of the gasoline samples was analyzed using the gas chromatography-mass spectrometry(GC-MS) method, and the aniline compounds were analyzed by solvent extraction and the GC-MS method. The ratios of alkanes, aromatics, olefins and other organic compounds in gasoline were 40.6%, 38.1%, 12.9% and 8.4%, respectively. The aromatic and benzene exceedances were 15 and 8 based on the China's gasoline standards(III), and they accounted for 48.4% and 25.8% of all the gasoline samples, respectively. Strong carcinogen aniline compounds were detected in all 31 samples, and the content of aniline compounds in 3 samples exceeded 1%. The high proportion of aromatics and olefins in the gasoline increased the emissions of carbon monoxide(CO) and toxics, as well as the atmospheric photochemical reactivity of exhaust emissions, which could hasten the formation of secondary pollutants. Our results are helpful for redefining government strategies to control air pollution in North China and relevant for developing new refining technology throughout China. 展开更多
关键词 ANILINE air pollution refining process EMISSIONS
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A chemometric method to identify selective ion for resolution of overlapping gas chromatography-mass spectrometry signal
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作者 MEI Zhen DU GuoRong +1 位作者 CAI WenSheng SHAO XueGuang 《Science China Chemistry》 SCIE EI CAS 2013年第5期656-663,共8页
A chemometric method to determine selective ion by using non-negative immune algorithm (NNIA) was proposed. In the method, the mutual projections of the chromatographic profiles at different m/z channel are calculat... A chemometric method to determine selective ion by using non-negative immune algorithm (NNIA) was proposed. In the method, the mutual projections of the chromatographic profiles at different m/z channel are calculated using NNIA. Suppose a GC-MS data with m retention time points and n mass channels, the projections of the GC-MS data onto a chromatographic profile at a mass channel will form a mass spectrum of ln vector. If the chromatographic profile at a selective mass channel is used, the extracted mass spectrum will be a correct one. Therefore, by comparing the extracted mass spectrum with a reference spectrum, the selective ion can be identified, and the corresponding chromatographic profile can be obtained at the same time. GC-MS data of 40-pesticide mixture was investigated by the method. The results show that both the mass spectral and the chromatographic information of the interested components can be extracted from the overlapping signals, except for the special cases of isomeric components with very similar mass spectra. 展开更多
关键词 gas chromatography-mass spectrometry selective ion detection immune algorithm CHEMOMETRICS resolution of overlapping peak
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