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1.
固相微萃取-气相色谱/质谱法分析白胡椒粉的风味成分   总被引:1,自引:0,他引:1  
采用固相微萃取采集白胡椒粉的挥发性成分,用色谱/质谱法分析鉴定,并用总离子流色谱峰的峰面积进行归一化定量分析其风味成分,鉴定出石竹烯(20.88%),1-甲氧基-4-(2-丙烯基)苯(20.57%),β-水芹烯(15.27%),3-蒈烯(14.56%),1-甲基-3-异丙基苯(3.62%),β-蒎烯(2.69%),芳樟醇(2.69%),香叶烯(2.36%),墨榄香烯(2.10%),胡椒烯(1.32%)等48种化合物。  相似文献   

2.
气相色谱-质谱法分析蘘荷花穗挥发油化学成分   总被引:3,自引:0,他引:3  
采用水蒸气蒸馏法提取黔产蘘荷花穗挥发油,并用气相色谱-质谱对其成分进行定性分析和峰面积相对含量的测定.共鉴定出45个化学成分,占挥发油总量的95.89%.主要成分为β-水芹烯(34.96%)、α-律草烯(13.09%)、β-榄香烯(7.31%)、β-蒎烯(6.50%)、α-水芹烯(6.07%)、α-蒎烯(3.87%)、β-石竹烯(3.18%)等。  相似文献   

3.
采用固相微萃取(SPME)技术,结合气相色谱/质谱(GC-MS)分析了火炬松枝条和针叶中的挥发性化合物,共鉴定了30种化学成分。其中枝条中分离鉴定出21种挥发性成分。主要成分为α-蒎烯、β-蒎烯、β-月蒎烯、反式-石竹烯、β-杜松烯、大根叶烯-D;针叶中分离鉴定出24种挥发性成分,主要成分为α-蒎烯、β-蒎烯、β-月桂烯、β-水芹烯、异长叶烯、反式-石竹烯、α-律草烯、大根叶烯-D、双环吉马烯和双环榄香烯。  相似文献   

4.
2-氨基吡啶镍配合物/MAO高活性催化β-蒎烯聚合研究   总被引:2,自引:0,他引:2  
合成了一系列2-氨基吡啶镍配合物(2-PyCH2NAr)NiBr,Ar=2,6-二甲基苯基(a),2,6-二异丙基苯基(b),2,6-二氟苯基(c).在助催剂甲基铝氧烷(MAO)存在下,该系列配合物能高活性催化β-蒎烯聚合,得到的聚β-蒎烯分子量明显比传统正离子聚合所得到的聚合物高.对配合物配体结构以及聚合条件对该聚合的催化活性以及聚合物分子量的影响进行了研究.所得聚合物经1H-NMR和13C-NMR分析表明,β-蒎烯聚合是通过正离子方式进行的,聚合中产生开环异构化,得到由环己烯和异丁烷结构单元交替组成的聚β-蒎烯.  相似文献   

5.
本文报道用毛细管气相色谱法及毛细管色谱-质谱-计算机体系对蒙古蒿精油化学成分进行分离和鉴定.30个单萜和含氧单萜化合物为2-甲基丁烯-[2]、甲叉环戊烷、7,7-二甲基-3-次甲基-双环(3,1,1)庚烷、α-(艹守)烯、α-蒎烯、莰烯、1-辛烯辛醇-3、β-(艹守)烯、β-蒎烯、α-菲兰烯、冰片烯、对甲基异丙基苯、松油烯醇-[1]、蒿属酮、γ-松油烯、β-松油醇、3,7,7-三甲基-双环(3,1,1)-2-庚醇、α-松油烯、马鞭烯酮、里哪醇、异(艹守)酮、(艹守)酮、樟脑、异胡薄荷酮、异龙脑、松油烯醇-[4]、α-松油醇、香桃木烯醇、反香芹烯醇和顺香芹烯醇.  相似文献   

6.
采用顶空-气相色谱-四极质谱法和顶空-气相色谱-飞行时间质谱法对鱼腥草挥发性成分进行检测,运用保留指数结合准确质量测定,分别从鱼腥草茎和叶中鉴定出49、39种挥发性组分,并采用峰面积归一化法测定各组分的相对含量。鱼腥草茎和叶中的挥发性成分差别较大。鱼腥草茎以α-蒎烯(12.24%)、β-蒎烯(22.42%)、月桂烯(11.98%)、乙酸冰片酯(10.97%)、甲基正壬酮(10.83%)为主要成分,而鱼腥草叶则以月桂烯(39.48%)、(Z)-β-罗勒烯(26.52%)、癸醛(10.35%)、桧烯(4.43%)、甲基正壬酮(2.44%)为主。结合保留指数和准确质量测定能显著提高质谱定性的准确性,有利于解决质谱检索时定性不确定的问题。  相似文献   

7.
张招贵 《应用化学》1990,7(2):60-61
β-蒎烯是一个重要的有机合成原料,但我国松节油中的β-蒎烯含量甚少,主要为α-蒎烯·将α-蒎烯异构化成为β-衍生物已有许多报道。本文将三乙基硼氨合物或三乙基苄基铵合硼烷使之与α-蒎烯反应成二(3-蒎烷基)硼烷,再经热异构重排成二(10-蒎烷基)硼烷,最后与双戊烯进行置换反应,顺利地制得了β-蒎烯。与Brown的方法相比,本法简便、安全,并且用我国合成樟脑生产中的副产物双戊烯代替了十二烯-(1)。  相似文献   

8.
本文报道用毛细管GC/MS联用技术分析野茴香挥发油的化学成份。气相色谱分离出40多个组份,质谱鉴定出24个组份,占挥发油含量的91.42%。它们是:醋酸乙酯,2-乙氧基丁烷、乙基丁基醚、2-甲基丙酸、1.2-二甲基咪唑、乙基苯,4-蒈烯、莰烯、苯甲醛、β-蒎烯、2-蒈烯、冰片烯、苯乙醛、桧烯、异-柠檬烯、β-松油醇、松油醇-4、α-松油醇、香芹酮、苘香脑、异-石竹烯、石竹烯、芹子烯和苯基-对甲苯基醚。  相似文献   

9.
以可再生的β-蒎烯衍生物诺蒎酮为原料,设计合成了一种新型的诺蒎酮基喹唑啉-2-胺铜离子荧光探针N-苄基-4-(4-(二乙氨基)苯基)-7,7-二甲基-5,6,7,8-四氢-6,8-桥亚甲基喹唑啉-2-胺(BNQ).探针BNQ在PBS/THF(V/V=8/2,10mmol·L-1,pH=7.4)溶液中对Cu2+表现出高度...  相似文献   

10.
分别使用苯乙烯-HCl加成物(a)和2-氯乙基乙烯基醚-HCl加成物(b)作为引发剂,TiCl4/Ti(OiPr)4(3∶1mol/mol)为活化剂,在nBu4NCl存在下,-40℃、CH2Cl2中,通过顺序活性阳离子聚合,合成了β-蒎烯与苯乙烯、对甲基苯乙烯的嵌段共聚物.又用带丙烯酰氧功能基的引发剂c [CH3CH(OCH2CH2X)Cl, X=OCOC(CH3)CH2] 引发β-蒎烯活性阳离子聚合,合成了β-蒎烯大分子单体.该大分子单体在AIBN引发下与甲基丙烯酸甲酯进行自由基共聚,获得主链为聚甲基丙烯酸甲酯、侧链为聚β-蒎烯的接枝共聚物.  相似文献   

11.
The spectral-polarization characteristics of absorption and phosphorescence of molecules of the initial form of nitro-substituted indolinospirobenzothiopyran were studied in oriented polyethylene films and in solutions with different polarity. An oscillator model of the electron transitions responsible for the formation of absorption and luminescence spectra was suggested. It was established that the principal differences in the spectral and photophysical properties of the compound studied and its oxygen-containing analog are associated with the fact that the electronegativity of the S atom is lower than that of the O atom. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1143–1146, June, 1997.  相似文献   

12.
非那雄胺能抑制5α-还原酶的活性,明显降低二氢睾酮水平,是一种治疗良性前列腺增生的有效药品。该合成工艺以甾烯酮酸为原料,将其与氯化亚砜反应,无须分离即与叔丁胺反应得17β-酰胺化合物,再氧化开环,环合,氢化,脱氢合成了非那雄胺。经元素分析、IR、1HNMR、13CNMR、MS分析表征了其结构。该法无须使用昂贵的2,2-二吡啶二硫化物和剧毒药品苯亚硒酸酐,且以乙酸铵代替氨气,降低了对设备的要求和腐蚀,更适用于工业生产。  相似文献   

13.

The heats of detonation of 20 simple high explosives and explosive mixtures were determined by means of an adiabatic detonation calorimeter designed by the authors. The results indicated that the performance of the instrument was reliable and the experimental data were very accurate. For explosive mixtures, there was a linear accumulative relationship between the heats of detonation of the explosive mixture and its components. Accordingly, the heats of detonation of explosive mixtures could be calculated directly from the heats of detonation of simple explosives and the characteristic heats of other components. The experiments showed that the gold or brass shell of the cylindrical charge could be substituted by a thick-walled porcelain shell, which had the advantage of cheapness.

  相似文献   

14.
Two vanilloids, (5E)-8-(4-hydroxy-3-methoxyphenyl)oct-5-en-4-one (1) and 4-[3-hydroxydecyl]-2-methoxyphenol (2), isolated from the dried seeds of Grains of Paradise (Aframomum melegueta), were synthesized; the latter compound was made as the S-enantiomer and the material derived from the seeds was found to be a 1:1.7 mixture of the R and S isomers. The synthetic route used should allow the preparation of analogs having extended alkyl chains and consequently different lipophilicity, and 3, a homolog of 2, was also prepared.  相似文献   

15.
In this review, the research of the author in the field of colloidal systems is summarized. The factors influencing colloidal stability are systematized and analyzed. Examples are presented to illustrate the practical utilization of the theory of stability of colloids and thin films.This review was prepared on the basis of the works of the author, which were awarded the State Premium for 1991 in the field of science and technology, chemistry section.Institute of Physical Chemistry, Russian Academy of Sciences, 117915 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 8, pp. 1708–1717, August, 1992.  相似文献   

16.
Main hydration products of two cement pastes, i.e. CSH-gel, portlandite (P) (and specific surface S) were studied by static heating, and by SEM, TEM and XRD, as a function of cement strength (C-33 and C-43) hydration time (th) and subsequent hydration in water vapour.Total change in mass on hydration and air drying, Mo, increased with strength of cement paste and with hydration time. Content of water escaping at 110 to 220°C, defined as water bound with low energy, mainly interlayer and hydrate water, was independent on cement strength but its content increased with (th). Content of chemically bound (zeolitic) water in CSH-gel, escaping at 220-400°C, was slightly dependent on strength and increased with (th). It was possibly derived from the dehydroxylation of CSH-gel and AFm phase. Portlandite water, escaping at 400-500°C, was independent on cement strength and was higher on longer hydration. Large P crystals were formed in the weaker cement paste C-33. Smaller crystals were formed in C-43 but they increased with (th). Carbonate formated on contact with air (calcite, vaterite and aragonite), decomposed in cement at 600-700oC. It was high in pastes C-33(1 month) and C-43(1 month), i.e. 5.7 and 3.3%, respectively; it was less than 1% after 6 hydration months (low sensitivity to carbonation) in agreement with the XRD study showing carbonates in the air dry paste (1month), and its absence on prolonged hydration (6 months) and on acetone treatment. Water vapour treatment of (6 months) pastes or wetting-drying increased this sensitivity.Nanosized P-crystals, detected by TEM, could contribute to the cement strength; carbonate was observed on the rims of gel clusters.This revised version was published online in November 2005 with corrections to the Cover Date.  相似文献   

17.
翟宗玺  刘树深  夏树屏 《化学学报》1990,48(10):946-950
用氧化镁氯化镁水溶液制备了8水合氯氧化镁[nMg(OH)2·MgCl2·8H2O], 并测定了其在盐酸中的溶解热, 实验结果表明, 氯氧化镁溶解热与n值呈线性关系, 根据溶解热求出5Mg(OH)2·MgCl2·8H2O和3Mg(OH)2·MgCl2·8H2O的生成热分别为-7727.1和5888.1kJ·mol^1^-。  相似文献   

18.
19.
The enthalpies of solution of several oxosulfides of rare-earth elements and the high-temperature enthalpies of oxosulfides and oxosulfates of lanthanum and yttrium were measured using solution calorimetry and high-temperature microcalorimetry techniques. Standard enthalpies of formation and some thermodynamic properties of oxosulfides and oxosulfates were calculated. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2 pp. 294–297, February, 1997.  相似文献   

20.
设计了铁的锈蚀实验,说明了铁钉的处理方法,增加了温度、酸、碱的影响条件,实现了铁跟蒸馏水及空气中氧气快速反应而生锈,使实验在5 min左右就能够得到准确的结果。  相似文献   

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