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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
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法呢基苯乙酮及其黄烷酮化合物的全合成 总被引:4,自引:0,他引:4
以2,4,6-三羟基苯乙酮和法呢基溴为原料,经一步反应以52.0%和6.5%的收率同时得到3-法呢基-2,4,6-三羟基苯乙酮(1)和4-法呢氧基-2,6-二羟基苯乙酮(2);然后以化合物1和3,4-二羟基苯甲醛为原料,经羟基保护、缩合、环化和去保护基共6步反应,以19.8%的总收率全合成了(±)-6-法呢基-3',4',5,7-四羟基黄烷酮(3).化合物1、2和3均是从澳大利亚植物Borroniaramosa中分离得到的新天然产物,此次为首次合成. 相似文献
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《有机化学》2016,(10)
通过硅胶和MCI柱色谱以及制备液相色谱等分离方法从白苞裸蒴中分离纯化得到6个含氮类化合物,经质谱和核磁共振等波谱技术将其结构分别鉴定为2-(1-羟基-6-甲氧基-4-氧亚基环己-2-烯-1-基)乙腈(1)、10-甲氧基-1-氧杂-3-氮杂螺[4.5]癸-2,6-二烯-8-酮(2)、2-(1-羟基-4-氧亚基环己-2,5-二烯-1-基)乙腈(3)、1-氧杂-3-氮杂螺[4.5]癸-2-烯-8-酮(4)、1-氧杂-3-氮杂螺[4.5]癸-2,6-二烯-8-酮(5)、对羟基苯乙腈(6).化合物1和2为新的含氮类化合物,化合物3为新的天然产物,其余化合物均为首次从该植物中分离得到. 相似文献
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有机质谱学在中药鱼腥草研究中的应用 总被引:29,自引:0,他引:29
研究了中药鱼腥草的挥发性物质和鱼腥草注射液的有效成分。用CC/MS方法鉴定了鱼腥草挥发性物质和鱼腥草注射液有效成分的化学组成,从二者中共鉴定出48个化合物。研究结果表明:二者中的化学组成基本相同。主要成分有:2-十一烷酮(甲基正壬酮)、癸酰乙醛(鱼腥草素)、苯甲醛、薄荷醇、冰片乙酸酯、2-十一烯醛、正十一烷醇、葵酸、δ-瑟林烯、肉豆蔻醚、斯巴醇、石竹烯氧化物、二苯胺及十六酸。占优势的化合物为甲基正壬酮,它在鱼腥草的挥发性物质中和鱼腥草注射液的有效成分中分别占9.8%和9.2%。作为鱼腥草中的特有物质癸酰乙醛(鱼腥草素),在鱼腥草的挥发性物质中和鱼腥草注射液的有效成分中分别占5.1%和2.6%。本文还讨论了甲基正壬酮和癸酰乙醛结构的确定。 相似文献
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通过三苄基氢化锡与1-乙快基环庚醇发生加成反应,得到了一种有机锡化合物 :(Z)-1-[2-(三苄基锡基)乙烯基]环庚醇(1).化合物1与I2,Br2和IC1按1:1和1 :2摩尔比投料进行卤化反应,得到6种构型保持的有机锡一卤化物2-4及二卤化物 5-7.有机锡一卤化物3与KOH乙醇溶液反应,得到了相应的有机锡氢氧化物8.以上 8种新化合物均通过熔点测定、元素分析、锡含量测定、红外光谱、核磁共振氢谱 对其结构进行了表征.并对其中的有机锡化合物1,3,4,6,7进行了体外抗P388 血癌活性测定,其中有机锡化合物4,6,7表现出强效. 相似文献
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灰竹挥发油化学成分分析 总被引:5,自引:0,他引:5
用溶剂提取法提取了灰竹的挥发性物质,用GC-MS法鉴定出22种化合物,其中主要成分(相对含量)为烯类(19.0%),醇类(39.9%),酯类(1.0%)、酸类(10.9%),酮类(2.3%)、芳香烃类(19.8%)和烷烃类(3.6%)化合物,占总检出量约97%。 相似文献
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采用超临界二氧化碳萃取含笑花的挥发油性成分,经毛细管气相色谱-质谱联用仪(GC-MS)分析,鉴定了其中的31个挥发性化合物,用气相色谱峰面积归一法测定各组分的相对百分含量。其挥发性组分主要是倍半萜氧化物、倍半萜类物质,其相对含量分别是49.87%和32.08%。该法获得的相对含量最高的是丁香烯环氧物(30.25%),其次是匙叶桉油醇(6.78%)、β-榄香烯(5.83%)。其它含量较高的成分依次是:长蠕孢吉码烯(5.62%)、棕榈酸(4.02%)、α依兰烯醇(3.26%)、β-香桦烯(3.25%). 相似文献
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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
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Cotton cellulose was swollen in a sodium hydroxide solution and carboxymethylated by a two-bath method for different periods of time for each process. The kinetics of acid hydrolysis and the crystallinity of the swollen and carboxymethylated samples were measured. The proportion of broken bonds, rate constants for hydrolysis, and permeability of cellulose to hydrolyzing agents were calculated. The susceptibility of glycosidic linkages to acid hydrolysis was improved by carboxymethylation more than by swelling in alkali. The increased accessibility of carboxymethylcellulose to acid was regarded as a consequence of increased intra-and intercrystalline swelling and of the glycosidic bonds' weakness caused by the electron-attracting carboxymethyl group on the C-6 position. 相似文献
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The aim of the presented work was the investigation of thermal oxidation of ilmenite in static air atmosphere. The investigations
were carried out by use of a derivatograph (MOM, Hungary). The changes of crystallographic structure of investigated samples
were identified by X-ray diffractometry on Philips PW-1710 diffractometer. In temperature above 500°C appears structure of
hematite Fe2O3. On the basis of the thermogravimetric measurements, the contracting area and contracting volume models were found as the
best fitting experimental data.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
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Cyclopropyl derivative of 2,6-di-tert-butylphenol is synthesized as a probe to investigate the mechanism of base-catalyzed autooxidation of phenol derivatives. Our study indicates that one electron reduction of molecular oxygen from phenolate gives phenoxyl radical 3, a key intermediate of autooxidation. The coupling of phenoxyl radical and superoxide radical gives peroxylate anion 4 and produces the final epoxy alcohol adduct 6. 相似文献
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微量钙的测定方法研究进展 总被引:5,自引:0,他引:5
介绍了1995-2006年期间测定微量和痕量钙的方法,如电感耦合等离子体-原子发射光谱法、原子吸收光谱法以及离子色谱法等的工作原理和特点,并说明了其测定微量钙的应用领域。并对微量钙的测定技术进行了展望(引用文献55篇)。 相似文献
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Thermal behaviour of sodium oxo-salts of sulphur: Na2SO4, Na2S2O7, Na2S2O6, Na2SO3, Na2S2O5, Na2S2O4, Na2S2O3, Na2S3O6 and of sulphides Na2S and Na2S2 was studied on heating up to 1000°C. The experiments were performed with anhydrous compounds obtained from commercial products
by recrystallisation and dehydration. The stage mechanisms of decomposition of anionic sub-lattices of the salts have been
proposed basing on the Górski’s morphological classification of simple species. The thermal stability and the stage decomposition
mechanisms were correlated with the structure and the potential chemical properties of the salt anions. The thermal decomposition
processes were studied by means of thermal analysis, and the decomposition products were identified by means of X-ray phase
analysis. 相似文献