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1.
以稻草秸秆快速热裂解生物油为样品,选取乙酸乙酯作为添加剂,按不同质量分数(分别为1%、6%、11%、16%和21%)添加到生物油中,考察原始生物油(空白组)及乙酸乙酯组生物油理化特性随贮存时间的变化规律。结果表明,随着乙酸乙酯添加质量分数增大,各乙酸乙酯组(1%、6%、11%、16%和21%)生物油最终pH值比空白组分别提高0.66%、2.33%、3.65%、4.32%和6.31%;最终含水率比空白组分别降低10.90%、20.17%、28.19%、30.27%和35.10%;最终运动黏度比空白组分别降低13.69%、39.08%、57.99%、66.00%和73.58%。FT-IR和GC-MS分析结果表明,添加乙酸乙酯能抑制生物油老化反应。此外,GC-MS分析结果还证实乙酸乙酯可以减少生物油内有机酸含量。  相似文献   

2.
The volatile constituents in the essential oil of Pelargonium quercetorum Agnew., growing wild in Kurdistan, Iran were investigated through GC and GC/MS technique. Twenty-six compounds, representing 21 (80.77%) of the total oil were identified. The main components were: alpha-pinene (25.28%), alpha-fenchyl acetate (20.63%), limonene (9.94%), beta-caryophyllene (8.20%), camphene (4.31%), delta-cadinene (3.32%), beta-pinene (3.21%), alpha-amorphene (2.80%), valencene (2.73%), ledene (2.25%) and p-cymene (1.63%).  相似文献   

3.
The chemical composition of the essential oils of the flowers and leaves of Anthemis hyalina were analyzed by GC and GC-MS for the first time. The oils were found to contain seventy-two components. cis-Chrysanthenyl acetate (14.9% and 17.8%), camphor (11.6% and 1.7%), terpinen-4-ol (8.3% and 1.2%), germacrene-D (5.1% and 2.1%), β-caryophyllene (4.1% and 5.4%), myrcene (3.6% and 16.9%), bicyclogermacrene (3.5% and 0.9%), α-pinene (2.3% and 4.1%), cis-β-ocimene (2.1% and 4.3%) and isospathulenol (0.4% and 4.3%) were found to be the major constituents of the oils of flowers and leaves respectively. Published in Khimiya Prirodnykh Soedinenii, No. 5, pp. 428–429, September–October, 2006.  相似文献   

4.
采用王水消解样品,利用原子吸收分光光度法,对重金属元素(Cu、Pb、Zn、Cd)在成都市东郊土壤中的垂直分布进行了研究。该法对Cu的回收率为98%~104%,精密度为2.75%;Pb的回收率为95~97%,精密度为3.11%;Zn的回收率为99%~101%,精密度为2.31%;Cd的回收率为97%~102%,精密度为3.32%,测定方法简单、准确。  相似文献   

5.
The fatty acid compositions of Nepeta viscida, N. cilicica, N. crinita, N. nuda ssp. glandulifera and N. aristata were analyzed by GC/MS. The main free fatty acids were found as linolenic acid (49.8-58.5%), linoleic acid (10.9-23.5%), oleic acid (11.5-19.2%), palmitic acid (5.2-6.8%) and stearic acid (2.0-3.7%) and, total fatty acid compositions of species were analyzed and results were found as 36.2-49.8%, 17.1-25.8%, 15.4-25.8%, 6.4-7.8%, and 2.7-4.1%, respectively.  相似文献   

6.
The in vitro cultivar of citrus contained 18.0% lipids after 12 weeks of germination of seed. The lipid was analyzed by GC procedure for its fatty acid composition. The oil contained seven major fatty acid constituents which were later identified by GC. The oil was further analyzed for its classes by means of thin layer chromatography and gas chromatography. The major portion of the lipid classes comprised of neutral lipids (93.9%) and polar lipids (6.1%). The identified neutral lipids comprised of hydrocarbon (1.4%), wax esters (1.5%), sterol esters (5.2%), triglycerides (52.3%), free fatty acids (1.3%), 1,3-diglycerides (6.0%), 1,2-diglycerides (5.0%), glycol (15.2%), sterols (6.0%), 2-monoglycerides (6.4%), 1-monoglycerides (5.3%) and the identified polar lipids comprised of phosphatidyl ethanolamine (1.8%) phosphatidyl choline (0.9%) lysophosphatidyl ethanolamine (1.8%) and phosphatidyl inositol (1.1%).  相似文献   

7.
The hydrodistilled oils from the fruits as well as the stems/leaves of Lomatium mohavense ssp. longilobum and Lomatium mohavense ssp. mohavense were analysed by GC and GC/MS. The respective oils from L. mohavense ssp. longilobum show (Z)-3-hexenol at 9.3% and 7.5%, β-sinensal at 18.8% and 6.8% and iso-α-sinensal at 18.9% and 19.3% as the major compounds. The corresponding oils from L. mohavense ssp. mohavense show β-phellandrene/limonene at 12.2% and 6.0%, β-elemene at 1.8% and 17.8%, β-caryophyllene at 8.9% and 7.8% and germacrene D at 18.8% and 10.8% as the predominant compounds.  相似文献   

8.
采用固相微萃取-气相色谱-质谱法分离和鉴定香樟籽的挥发性成分,用归一化法测定其相对含量。共分离出76种组分,鉴定出47种化合物,其含量占总挥发性成分的97.4%。主要挥发成分为樟脑(57.89%)、柠檬烯(12.68%)、α-蒎烯(4.42%)、莰烯(2.69%)、香橙烯(2.34%)、伞花烃(2.26%)及β-蒎烯(2.12%)。  相似文献   

9.
辣椒油化学成分的气相色谱-质谱分析   总被引:21,自引:0,他引:21  
采用溶液进样和顶空固相微萃取进样,GC-MS分离鉴定,总离子流色谱的峰面积归一化法定量分析了辣椒油的化学成分;在溶液进样方法中,鉴定的主要成分相对含量依次为辣椒碱(37.0%)、亚麻酸乙酯(26.3%)、棕榈酸(10.9%)、二氢辣椒碱(10.1%)、邻苯二甲酸二乙基己基酯(1.2%)和硬脂酸(1.1%)等;在顶空固相微萃取方法中,鉴定的成分主要为易挥发的头香成分,依次为顺-2,4α,5,6,9,9α-六氢-3,5,5,9-四甲基-1H-苯并环庚烯(22.9%)、2,4α,5,6,7,8,9,9α-八氢-3,5,5-三乙基-1H苯并环庚烯(9.2%)、正十五烷(6.7%)、艾蒿脑(5.9%)、正戊酸己酯(5.2%)、正十六烷(3.3%)、麝香内酯(3.3%)、正十七烷(2.4%)及5,6,7,7α-四氢-4,4,7α-三甲基-2(4H)-苯并呋喃酮(2.2%)等。  相似文献   

10.
介绍铝合金化学成分标准物质的研制过程。采用中频感应电炉熔炼法制备了铝合金化学成分标准物质候选物,并对标准物质候选物的均匀性和稳定性进行了考察。选择6家具有资质的实验室对研制的标准物质中各化学成分进行协作定值,并对各元素定值的不确定度进行评定。结果表明,在95%的置信区间内标准物质均匀性良好,经过13个月稳定性考察试验,标准物质稳定性良好。Si,Fe,Cu,Mn,Mg,Ti,Cd,V,Zr,B,Sn,Zn的定值结果分别为0.013 8%,0.012 5%,2.868%,0.185%,0.014 0%,0.082 8%,0.041 7%,0.032 9%,0.031 4%,0.003 8%,0.003 4%,0.025 6%,定值结果的相对扩展不确定度为1.4%~9.0%(k=2)。研制的标准物质达到相关技术要求,可用于该类铝合金材料的质量控制。  相似文献   

11.
The leaf and inflorescence essential oils of Plectranthus rugosus Wall. (syn. Rabdosia rugosa Wall.) and Plectranthus incanus L. (syn. Plectranthus mollis L.), which grow wild in Uttarakhand, India, were analysed and compared by capillary gas chromatography and gas chromatography-mass spectrometry. The analysis led to the identification of 43 constituents, forming 89.5-93.6% of the total oil compositions. Both leaf and inflorescence oil of P. rugosus were dominated by sesquiterpene hydrocarbons (71.8%, 71.7%) represented by β-caryophyllene (36.2%, 29.8%), germacrene D (25.2%, 28.2%) and α-humulene (6.6%, 8.6%) as the major constituents. Conversely, the leaf and inflorescence oil of P. incanus were dominated by monoterpenoids (74.4%, 65.8%) with piperitenone oxide (44.2%, 38.5%), piperitone (8.6%, 12.2%) and terpinolene (14.5%, 10.2%) as major constituents. Piperitenone oxide, piperitone, cis- and trans-piperitols and trans-piperitol acetate were the marker constituents in P. incanus, which were not noted in the essential oil of P. rugosus.  相似文献   

12.
为了探究丙酮与乙酸乙酯对生物油储存特性的影响,将不同质量分数(3%、6%、9%、12%、15%)的丙酮和乙酸乙酯分别加入到生物油中,考察各组生物油理化特性随储存时间的变化。结果表明,添加丙酮和乙酸乙酯降低了生物油的含水率,且乙酸乙酯对生物油水分的降低效果优于丙酮。储存35 d后,15%乙酸乙酯组生物油的含水率为13.41%,比空白组(16.32%)降低了17.8%。加入添加剂后各组生物油的运动黏度均显著下降,与乙酸乙酯相比,丙酮对运动黏度影响较大。随着添加剂添加比例的增加,生物油运动黏度降低。储存35 d后,添加丙酮质量分数为3%、6%、9%、12%、15%的实验组生物油的运动黏度比空白组分别降低了37.20%、57.78%、71.92%、79.79%、84.67%。两种添加剂均能使生物油的pH值略微增大。红外光谱分析和气相色谱质谱联用分析显示,丙酮和乙酸乙酯抑制了生物油的老化反应。  相似文献   

13.
邹耀洪 《分析化学》1995,23(1):93-96
本文应用同时蒸馏-萃取装置提取了薏苡仁的挥发物质,用GC/MS方法分离鉴定了55种成份,其中主要成份为醇类(14.1%)、醛类(9.85%)、酮类(3.07%)、酸类(5.96%)、酯类(2.74%)、烃与萜类(50.43%)、杂环类(12.45%),占总挥发物质的98.6%。  相似文献   

14.
通过电解实验分别考察了5个阴极电还原反应和1个阳极电氧化反应在加入添加剂前后电流效率和转化率的变化。所选择的6个反应可以分为2类,一类是原料以分子形式存在于电解液中的反应,另一类是原料以离子形式存在于电解液中的反应。实验间二硝基苯电还原制间苯二胺,3-甲基吡啶氧化制烟酸和邻硝基酚电还原制邻氨基酚(酸性条件下)属于前一类反应,加入添加剂后,它们的电流效率分别由原来的65.69%、28.00%和45.09%变为66.15%、28.45%和37.07%,说明添加剂对原料以分子形式存在的反应没有作用或有抑制作用。实验邻硝基酚电还原制邻氨基酚(碱性条件下),丁二酸的电解全盛和水杨酸电还原制水杨醛属于后一类反应,加入添加剂后,它们的电流效率分别从原来的49.37%、65.06%和24.55%提高到75.80%、78.60%和30.06%,说明添加剂能够提高原料以离子形态存在的反应的电流效率。  相似文献   

15.
The chemical compositions of the essential oils obtained by hydrodistillation from the aerial parts of Scutellaria diffusa, Scutellaria heterophylla and Scutellaria salviifolia were separately identified simultaneously by gas chromatography and gas chromatography-mass spectrometry. The main components were determined as hexadecanoic acid (30%) and caryophyllene oxide (9%) in the oil of S. diffusa. Germacrene D (21%), hexadecanoic acid (16%) and β-caryophyllene (13%) were found as major components in the oil of S. heterophylla. The main components of the oil of S. salviifolia were germacrene D (40%), bicyclogermacrene (14%) and β-caryophyllene (11%). Overall, individually 63, 68 and 43 constituents were identified in the aerial parts of S. diffusa, S. heterophylla and S. salviifolia essential oils representing 92.1%, 89.9% and 90% of the total, respectively.  相似文献   

16.
Origanum tyttanthum Gontsch. was collected from two different sites in south-central Tajikistan. The essential oils were obtained by hydrodistillation and analyzed by gas chromatography-mass spectrometry. A total of 52 compounds were identified representing 99.0-100% of total oil compositions. The major components of Origanum tyttanthum Gontsch. oil were carvacrol (34.3-59.2%), thymol (10.8-46.4%), p-cymene (0.7-7.3%), beta-thujone (1.9-4.1%), piperitenone oxide (0.1-3.8%), gamma-terpinene (0.3-3.5%), cis-piperitone epoxide (0.8-3.3%), carvacrol acetate (0.4-2.4%), menthone (0.6-2.1%) and borneol (1.0-2.3%).  相似文献   

17.
The essential oils from stems, leaves, inflorescences, and both unripe and ripe infructescences of Smyrnium olusatrum L. (Umbelliferae) collected in Greece were obtained by hydrodistillation and analyzed by GC-FID and GC-MS. Fifty-eight components were identified. Among the samples analyzed, the differences observed were mainly quantitative. All oils were characterized by the abundance of sesquiterpenes. The major components of the stem and leaf oils were furanoeremophil-1-one (54.3% and 28.7%, respectively) and curzerene (18.8%, 29.0%). The main constituents of the inflorescence oil were curzerene (38.1%), germacrone (20.2%) and furanoeremophil-1-one (20.0%), while those of the unripe and ripe infructescence oils were 1beta-acetoxy-furanoeudesm-4(15)-ene (22.1%, 30.8%) and curzerene (29.7%, 17.4%).  相似文献   

18.
This work aimed to study the recovery of three types of waste by the process of pyrolysis: biomass, plastics and used tyres. The effects of experimental conditions in products yield and composition were studied. The increase of reaction time increased alkane content both in gas phase from 53% to 70% v/v and in liquid fraction from 48% to 60% w/w. The rise of reaction temperature led to a decrease of liquid yield (from 82% to 73% w/w), which was followed by the increase of solids and gases. The increase of reaction temperature also allowed the increase of the alkane content in gas phase from 39% to 70% v/v. The parameter that most affected products yield and composition was plastics content on the wastes initial mixture. The enhancement of this parameter increased liquid yield from 33% to 92% w/w, at the expense of solids and gases contents and also decreased aromatic contents from 52% to 28% w/w.  相似文献   

19.
The chemical composition of the essential oil from the aerial parts of Chromolaena odorata, collected from Phitsanulok, Thailand was analyzed by means of GC-(FID) and GC-MS. Twenty-two constituents were identified. The major components were pregeijerene (17.6%), germacrene D (11.1%), alpha-pinene (8.4%), beta-caryophyllene (7.3%), vestitenone (6.5%), beta-pinene (5.6%), delta-cadinene (4.9%), geijerene (3.1%), bulnesol (2.9%), and trans-ocimene (2.2%).  相似文献   

20.
Summary The simultaneous quantitation of acids and sugars as their trimethyl silyl (TMS) derivatives has been extended in order to identify and quantitate the simple acid and sugar constituents in the hydrolyzates of various immunostimulant, water-soluble polysaccharides obtained from various Basidiomycetes, such as Armillariella mellea, Auricularia auricula-judae, Coriolus versicolor, Flammulina velutipes, Fomes fomentarius, Ganoderma applanatum, Ganoderma lucidum, Pleurotus ostreatus, Schizophyllum commune, Trametes hirsuta. Optimum hydrolysis conditions, performed with 2 M trifluoroacetic acid (TFAA) for five hrs, proved the presence of several sugars and acids with maximum recovery. (i) the total sugar/sugar alcohol content of polysaccharides varied between 20- and 65% and consisted of arabitol (0.01–10.2%), arabinose (0.09–1.3%), ribose (0.2–1.8%), fucose (0.3–1.2%), mannitol (0.01–5.3%), sorbitol (0.01–0.05%), galactiol (0.04%), fructose (0.08–0.8%), galactose (0.9–29%), glucose (10–53%), uronic acids (0.14–3.7%), sucrose (0.03–2%), trehalose (0.2–1%), cellobiose (0.01–0.6%), maltose (0.2–1.9%), other disaccharides (0.2–8%). (ii) The total of acids varied from 1.5 to 30% including o-phosphoric (1.3–19%), malic (0.08–4.7%), citric (0.08–4.7%), isocitric; (3%) and C16−C18 fatty acids (1–6%).  相似文献   

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