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131.
132.
用气相色谱-质谱法对山东昆嵛山产油松节挥发油进行化学成分的分析。采用水蒸气蒸馏法从油松节中提取挥发油。采用不同类型的毛细管柱进行分析,找出最佳分析条件,用归一化法测定其含量,并用气相色谱-质谱法对化学成分进行鉴定。共鉴定了48个成分,占挥发油总成分的84%以上。结果表明,此方法稳定可靠,重现性好,适用于中药挥发油的化学成分分析。 相似文献
133.
N. A. Talzhanov D. T. Sadyrbekov F. M. Smagulova R. M. Mukanov V. A. Raldugin M. M. Shakirov A. V. Tkachev G. A. Atazhanova B. I. Tuleuov S. M. Adekenov 《Chemistry of Natural Compounds》2005,41(2):178-181
Chemical components from the aerial part of the Kazakhstan population of Artemisia pontica, from which the rarely encountered flavonoids 7-O-methyl- and 4′,7-di-O-methyl-esters of apigenin were isolated for the first time, were identified. The complete chemical composition of the essential oil was established using GC-MS.__________Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 143–145, March–April, 2005. 相似文献
134.
运用化学计量学方法探索姜科植物温郁金不同药材的挥发油色谱指纹图谱中化学成分的异同.指纹图谱数据由高效液相色谱法获得,流动相为乙腈-0.20%磷酸水溶液梯度洗脱,流速1.0 mL/min,柱温20 ℃,光谱记录范围为200~340 nm.应用渐进子窗口比较法对中药温郁金、温莪术及片姜黄挥发油指纹图谱-光谱数据进行比较分析.经比较,温郁金和温莪术的色谱指纹图谱中,至少分别有15和6种单独的化学成分存在,两者的共有的化学成分有18种;温莪术与片姜黄的共有化学成分13种,而单独存在的化学成分至少分别有4和7种. 相似文献
135.
136.
Isotope dilution determination of polycyclic aromatic hydrocarbons in olive pomace oil by gas chromatography-mass spectrometry 总被引:2,自引:0,他引:2
Diletti G Scortichini G Scarpone R Gatti G Torreti L Migliorati G 《Journal of chromatography. A》2005,1062(2):247-254
A gas chromatographic (GC) method with mass spectrometry detection (MS) for the determination of eight polycyclic aromatic hydrocarbons (PAHs) in olive pomace oil has been developed. The oil was diluted with n-pentane and extracted by liquid-liquid partition with dimethyl sulphoxide (DMSO). After water addition and back-extraction with cyclohexane, a thin-layer chromatography on silica gel was performed as a further purification step. The PAHs spot was scraped off from the plate and the final extract was concentrated and analysed by GC-MS in full scan mode. The eight PAHs under investigation were determined in the presence of the corresponding labelled compounds added as internal standards to the sample at the beginning of the analytical process. The identified PAHs were then quantified by the isotope dilution methodology assuring the compensation of the concentration of each analyte for any variation in the sample preparation. The method precision was satisfactory with relative standard deviation (R.S.D.) values in the range 3.6-12.7% for all PAHs. The average recovery rates ranged from 69.0 to 97.5%. Accuracy was also calculated for benzo[k]fluoranthene, benzo[a]pyrene, indeno[1,2,3-cd]pyrene and benzo[ghi]perylene by analysing a certified reference material (CRM 458, coconut oil) with adequate results. All response curves exhibited a linear fit from 0.1 to 10 microg ml(-1) and the determination coefficients R2 were better than 0.9942. The limits of detection (0.1-0.4 microg kg(-1)) were acceptable when compared with the maximum permitted limit of 2 microg kg(-1) for each of the eight considered PAHs and 5 microg kg(-1) for the sum of the eight PAHs established by the Italian legislation. Measurement uncertainty was finally calculated identifying and quantifying the uncertainty components of the analytical process. The relative expanded uncertainties (Uc), expressed as percent values were in the range 8.5-11.4% thus appropriate for residues quantification in the range of concentrations considered in the present study. 相似文献
137.
J. López-Cervantes D.I. Sánchez-Machado J. Simal-Lozano P. Paseiro-Losada 《Chromatographia》2003,58(5-6):321-326
Summary A high-performance liquid-chromatographic method with UV detection (HPLC–UV) has been developed for quantification of ethylene terephthalate oligomers in olive oil, from which they were extracted with acetonitrile. Oligomers, from monomers (M1) to pentamers (M5), were jointly and/or individually identified by liquid chromatography with mass spectrometry (electron-impact mass spectrometry (EIMS) low- and high-resolution) and were quantified by HPLC–UV using an acetonitrile solution of the major oligomer (the trimer M3) as standard. For M3 recovery was 98.9%, the detection limit was 60 g L–2, and method precision was 2.03% (RSD). Migration of oligomers M1–M5 into 50 mL olive oil sealed in each of two brands of 10 cm × 10 cm poly(ethylene terephthalate) roasting bag was evaluated under two sets of conditions that approached but remained below the limit at which the bag material became physically deformed – heating for 7 min at 850 W in a microwave oven, or for 60 min at 200 °C in a conventional oven. Total migration was approximately 2.7 mg dm–2 under the former conditions and 3.5–4.1 mg dm–2 under the latter.Presented at the International Symposium on Separation and Characteristics of Natural and Synthetic Macromolecules, Amsterdam, The Netherlands, February 5–7, 2003 相似文献
138.
人参挥发油的提取和分析 总被引:7,自引:0,他引:7
应用GC-MS-DS联机分析人参挥发油是当前较好的方法,但人参挥发油的提取方法和GC-MS条件的选择明显影响人参挥发油这一复杂天然混合物的分离和鉴定。本工作严格控制提取条件,提高了挥发油收率,达0.95%;选择最佳GC-MS条件,鉴定出76种化合物,该法稳定重现性好。 相似文献
139.
Jing CHAO Xing Yuan ZHANG Jia Bing DAI Zhen GE Lin Lin FENG 《中国化学快报》2006,17(8):1121-1124
Aqueous acrylic-polyurethane dispersions have become one of the major types of materials used in coating, paint and adhesive industries, because of excellent properties and environmental advantages1-5. However, some properties for cured film such as water… 相似文献
140.
Presti ML Ragusa S Trozzi A Dugo P Visinoni F Fazio A Dugo G Mondello L 《Journal of separation science》2005,28(3):273-280
Traditional hydrodistillation (HD), supercritical fluid extraction (SFE), organic solvent extraction (SE), and water microwave assisted hydrodistillation (MAHD) techniques were compared and evaluated for their effectiveness in the isolation of rosemary essential oil. The microwave assisted hydrodistillation technique was optimized in terms of both delivered power and time duration. The extracts/distillates were analyzed by GC and GC-MS. Microwave distillation, which exploits the physical action of microwaves on plants, showed a series of advantages over the other approaches: low cost, use of water in sample pre-treatment step, greatly reduced isolation time, and attainment of high quality essential oil distillate. Moreover, the absence of environmental impact of this innovative technique was also emphasized. 相似文献