共查询到19条相似文献，搜索用时 146 毫秒
1.
研究了以5-降冰片烯-2,3-二酸酐(NA)和甲醇为原料、甲苯为带水剂,磷酸做催化剂,合成5-降冰片烯-2,3-二羧酸二甲酯的过程。在此条件下,产率可达89.6%以上。并通过高效液相色谱仪(HPLC)分析、傅立叶变换红外光谱仪(IR)、气相色谱-质谱(GC-MS)对产物进行了表征。 相似文献
2.
目的：利用GC—MS方法分析油松松针中挥发油成分．方法：以水蒸汽蒸馏方法提取油松松针挥发油,利用气相色谱——质谱联用技术对提取的挥发油成分进行分析．结果：利用谱图检索油松松针中挥发油的主要有12种主要成分,分别为龙脑（45．133％）、醋酸冰片酯（11．212％）、1R-α-蒎烯（11．173％）、β-石竹烯（10．291％）、杜松烯（7．083％）、松油烯-4-醇（4．226％）、古巴烯（3．368％）、1,7-辛二烯、3-亚甲基（1．985％）、β-蒎烯（1．932％）、8-亚甲基-（1α,2α4α,5α）三环[3,2,1．02,8]辛烷（1．785％）、莰烯（1．328％）、反-松香芹醇（0．480％）．结论：油松松针中挥发油是一种具有较好应用前景的天然药用资源． 相似文献
3.
采用固相微萃取/气相色谱／质谱法分析毕拨挥发油化学成分,在毕拨挥发油化学成分中,共分离出115个成分,鉴定出其中的81个成分,已鉴定成分占总挥发油成分峰面积的97．83％;主要为萜烯类及其含氧衍生物等化合物,含量较高的成分是α-律草烯（4．44％）、α-姜黄烯（4．94％）、大根香叶烯-d（5．67％）、十五烷（12．30％）、β-没药烯（6．20％）、十七（碳）-8-烯（6．66％）、8-十七（碳）烯（9．29％）、十七烷（9．07％）等化合物。 相似文献
4.
槐米挥发油化学成分GC-MS分析 总被引：1，自引：0，他引：1
采用水蒸气蒸馏法从槐米中提取挥发油,利用气相色谱／质谱联用技术（GC-MS）对槐米挥发油的化学成分进行研究．结果显示：共分离到39个化合物,鉴定了其中的28个,占挥发油总量的95．227％．主要包括8-十七碳烯（26．358％）,[S-（R^＊,S^＊）]-5-（1,5-二甲基4-己烯基）-2-甲基-1,3-环己二烯（12．093％）,石竹烯（11．969％）,2-甲氧基-3-（2-丙烯基）苯酚（8．460％）等． 相似文献
5.
采用硅胶、大孔树脂、葡聚糖凝胶、MCI树脂以及高效液相半制备色谱等色谱分离方法，从茜草科耳草属的白花蛇舌草95%乙醇提取物的乙酸乙酯萃取部位分离出9个化合物，运用核磁共振等波谱技术和文献对比法鉴定了9个化合物的结构，分别为：毛地黄内酯（1），琥珀酸二甲酯（2），琥珀酸二乙酯（3）,5-(羟甲基)-2-糠醛（4），香草醛（5），对羟基苯甲酸乙酯（6）,4-甲氧基苯-1, 2-二醇（7），香草酸（8），东莨菪内酯（9）.化合物1是降11碳倍半萜，化合物2和3是链状羧酸酯类衍生物，化合物1—3为首次从该植物中分离得到. 相似文献
6.
综合利用多种色谱分离方法和材料对辐裂锈革菌提取物中的化学成分进行分离,并运用波谱学技术（ NMR、MS、UV、IR）对所分离得到的化合物进行结构解析。从辐裂锈革菌甲醇提取物中分离鉴定了8个化合物：（1）grifolic acid,（2）4-（2′,5′-dihydroxyphenyl）-（E）-3-buten-2-one,（3）反式-1-（4′-羟基苯基）-丁-1-烯-3-酮,（4）原儿茶醛,（5）对羟基苯甲醛,（6）亚油酸,（7）麦角甾-5,7,22-三烯-3β醇,（8）过氧麦角甾醇。所有化合物均是首次从该菌中分离得到。 相似文献
7.
SPME／GC—MS法分析柠檬草挥发气体成分 总被引：1，自引：0，他引：1
利用固相微萃取SPME／GC—MS技术分析了柠檬草的挥发气体成分。结果表明：柠檬草中共鉴定出25种主要挥发性化合物,以碳氢化合物和醛类物为主,包括β-月桂稀（34．34％）、石竹烯（0．493％）、莰烯（0．646％）、D-柠檬烯（0．126％）、1R-α-蒎烯（0．73％）、柠檬醛（26．5％）、3,7二甲基-2,6-辛二稀醛（26．63％）等。经过精制的柠檬草精油含有酮和烃类化合物,主要有：2-十一酮（0．606％）、2-甲基-5-（1-甲基乙基）环己酮（1．83％）、（1S）-6,6-二甲基-二乙基二环-[3,1,1]-庚烷,（0．34％）、1,4-双亚甲基-环已烷,（0．176％）,3-丙基-环已基（0．1667％）。 相似文献
8.
邝代治 《衡阳师范学院学报》1999,20(6):40-44
研究了三羰基（五甲二硅基）环戊二烯基羰基卤-钼［（η5-C5H4SiMe2SiMe5）（CO）3Mo－XX=Cl、Br、I]和（五甲二硅基）环戌二烯基双三苯基膦羰基溴钼[（η5-C5H4SiMe2SiMe5）（PPh3）2（CO）Mo—Br]以及二羰基（五甲二硅基）环成二烯基环氧亚成基卤钼{η5-C5SH4SiMe2SiMe5）（CO）2[CO（CH2）3]Mo－XX=Br、I}化合物的红外光谱,硅与茂环发生电子反馈作用表现在红外光谱振动吸收发生位移,从而讨论硅甲基取代环成二烯后对化合物的红外光谱的影响。并对标题化合物的主要红外吸收带进行归属。 相似文献
9.
阴香叶挥发性物质的GC／MS分析 总被引：1，自引：0，他引：1
利用顶空固相微萃取技术（SPME）吸附采集阴香叶的挥发性物质,采用气相色谱-质谱（GC／MS）技术对其进行分析研究．结果显示,从阴香叶中鉴定出39种化学物质,占挥发性物质总量的98．48％,其主要挥发性物质为龙脑（19．68％）、桉树脑（10．49％）、乙酸双环【2．2．1】庚-2-基酯（9．65％）、α-蒎烯（7．36％）、D-柠檬烯（6．45％）、石竹烯（5．80％）等,这些物质的共同作用形成了阴香叶特殊的香味． 相似文献
10.
采用同时蒸馏萃取方法对松乳菇挥发性成分进行提取,并用气相色谱—质谱法对提取物进行化学成分分析.从同时蒸馏萃取提取物中鉴定出了67个成分,并以归一化法测定了各个成分的质量分数.其中超过2%的有9种：1-辛烯-3-醇（2.27%）,丁酸丁酯（13.52%）,（E）-2-辛烯醛（2.88%）,n-癸酸（4.99%）,[1 aR-（1 a..α,4..β,4 a..β,7..β,7 a..β,7b..α）]-十氢-1,1,4,7-四甲基-1H-环丙烯并[e]薁（4.16%）,n-十六烷酸（4.75%）,（Z）-9,17-十八碳二烯醛（5.19%）,（E）-9-十八碳烯酸（3.33%）,十八烷酸（2.13%）. 相似文献
11.
The metal oxide/nitrogen-doped carbon (NC) compounds zirconium oxide/NC (ZrO2/NC) and cerium oxide/NC (CeO2/NC) were synthesized via the pyrolysis of polyaniline on the metal oxide surface. The characterization of the ZrO2/NC and CeO2/NC catalysts showed more active CO2 reduction reaction activity than that of NC catalyst without metal oxide. Gas chromatography analysis revealed that CO and H2 were the primary products, and no liquid-phase products were detected via proton nuclear magnetic resonance spectroscopy or high-performance liquid chromatography. The maximum Faraday efficiency of ZrO2/NC reached 90% at − 0.73 V (vs. RHE), with the current density of CO at 5.5 mA/cm2; this Faraday efficiency value was higher than that of NC (41%), with the current density of CO at 3.1 mA/cm2. The interaction between the metal oxide and carbon allowed the efficient formation of defect sites, especially imine-type nitrogen, strengthening the adsorption of the key reaction intermediate CO2•− and thus promoting the CO2 reduction reaction.
相似文献12.
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. . 相似文献
13.
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-5 MS capillary column. 相似文献
14.
报道了采用同时蒸馏-萃取法提取冠心苏合丸中的挥发性组分,测得冠心苏合丸中的挥发性组分含量为14%.利用GC-MS方法对所获得的挥发性组分进行分析,通过G1701BA化学工作站检索NIST98谱图库,并结合标准谱图库和有关文献,从其挥发性组分中确定出14种化学成分,占冠心苏合丸中挥发性组分总检出量的97.27%.用峰面积归一化法通过化学工作站数据处理系统,得出各化学成分在挥发性组分中的相对百分含量.主要挥发性组分是冰片、异冰片和苯甲酸苄酯.并采用气相色谱法对冠心苏合丸中冰片的含量进行了测定.结果,冰片浓度在1.0～5.0 mg/mL范围内与冰片对内标物的色谱峰面积比值成良好的线性关系,冰片的平均回收率为101.2%. 相似文献
15.
毛细管气相色谱监测空气中苯、甲苯和二甲苯 总被引：4，自引：0，他引：4
用活性炭吸附-CS2(溶剂)解吸气相色谱法监测室内空气中苯、甲苯和二甲苯。对“居住区大气中苯、甲苯和二甲苯卫生检验标准方法-气相色谱法”(GB11737-89)进行了改进，并对改进方法的灵敏度、精确度、准确度、稳定性等进行了测试，结果表明该方法的主要技术指标符合室内环境空气监测的要求。 相似文献
16.
从牛蒡子中分离得到6个化合物,分别鉴定为:β-谷甾醇(1),胡萝卜甙(2),牛蒡子甙(3),牛蒡酚A(4),牛蒡酚B(5),松脂醇(6).化合物6为首次从该种植物中分离得到. 相似文献
17.
XIA Rui ZHANG Yuan ZHANG Meng-heng LIU Ke-xin WU Jie-yun ZHENG Zhi-rong GONG Yao 《重庆大学学报(英文版)》2015,14(3):87-100
Increasing incidents of indoor air quality (IAQ) related complaints lead us to the fact that IAQ has become a significant occupational health and environmental issue. However, how to effectively evaluate IAQ under different scale of multiple indicators is still a challenge. The traditional single-indicator method is subjected to uncertainties in assessing IAQ due to different subjectivity on good or bad quality and scalar differences of data set. In this study, a multilevel integrated weighted average IAQ method including initial walking through assessment (IWA) and two-layers weighted average method are developed and applied to evaluate IAQ of the laboratory building at the University of Regina in Canada. Some important chemical parameters related to IAQ in terms of volatile organic compounds (VOCs), methanol (HCHO), carbon dioxide (CO2), and carbon monoxide (CO) are evaluated based on 5 months continuous monitoring data. The new integrated assessment result can not only indicates the risk of an individual parameter, but also able to quantify the overall IAQ risk on the sampling site. Finally, some recommendations based on the result are proposed to address sustainable IAQ practices in the sampling area. 相似文献
18.
Nitrateremovalfromdrinkingwaterisoneofthemainproblemsinwaterresearch. Severalnitrateremovalmethodssuchasionexchange, reverseosmosis, electrodialysis, distillation, chemicalreductionandbio denitrificationhavebeenemployedwithdifferentratesofefficiency[1, 2]. Bio denitrificationhasbeenprovedtobeoneofthemostfeasible, advanced,selectiveandcosteffectiveprocessesforremovingnitratebydissimilationreduction[3], whichtransformsnitrateintonitrogengas[4]. Thisprocesshasbeenappliedtonitrogenremovalofwas… 相似文献
19.
Xuan Cai Rong-zhang Mai Jing-jing Zou Hong-yan Zhang Xiang-ling Zeng Ri-ru Zheng Cai-yun Wang 《Journal of Zhejiang University. Science. B》2014,15(7):638-648
Objective: Aroma is the core factor in aromatherapy. Sensory evaluation of aromas differed among three sweet osmanthus (Osmanthus fragrans) cultivar groups. The purpose of this study was to investigate the aroma-active compounds responsible for these differences. Methods: Gas chromatography-olfactometry (GC-O) and GC-mass spectrometry (GC-MS) were used to analyze the aroma-active compounds and volatiles of creamy-white (’Houban Yingui’, HBYG), yellow (’Liuye Jingui’, LYJG), and orange (’Gecheng Dangui’, GCDG) cultivars. Results: Seventeen aroma-active compounds were detected among 54 volatiles. trans-β-Ocimene, trans-β-ionone, and linalool, which were major volatiles, were identified as aroma-active, while cis-3-hexenyl butanoate, γ-terpinene, and hexyl butanoate were also aroma-active compounds, although their contents were low. Analysis of the odors was based on the sum of the modified frequency (MF) values of aroma-active compounds in different odor groups. HBYG contained more herb odors, contributed by cis-β-ocimene and trans-β-ocimene, while LYJG had more woody/violet/fruity odors released by trans-β-ionone, α-ionone, and hexyl butanoate. In GCDG, the more floral odors were the result of cis-linalool oxide, trans-linalool oxide, and linalool. Conclusions: Aroma-active compounds were not necessarily only the major volatiles: some volatiles with low content also contributed to aroma. The aroma differences among the three cultivars resulted from variation in the content of different odor groups and in the intensities of aroma-active compounds. 相似文献