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Epoxidation of Unsaturated Fatty Acid Methyl Esters in the Presence of SO_3H-functional Brφnsted Acidic Ionic Liquid as Catalyst 被引量:15
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作者 蔡双飞 王利生 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2011年第1期57-63,共7页
The epoxidation of unsaturated fatty acid methyl esters(FAMEs)by peroxyacetic acid generated in situ from hydrogen peroxide and acetic acid was studied in the presence of SO3H-functional Brnsted acidic ionic liquid (I... The epoxidation of unsaturated fatty acid methyl esters(FAMEs)by peroxyacetic acid generated in situ from hydrogen peroxide and acetic acid was studied in the presence of SO3H-functional Brnsted acidic ionic liquid (IL)[C3SO3HMIM][HSO4]as catalyst.The effects of hydrogen peroxide/ethylenic unsaturation ratio,acetic acid concentration,IL concentration,recycling of the IL catalyst,and temperature on the conversion to oxirane were studied.The kinetics and thermodynamics of unsaturated FAMEs epoxidation and the kinetics of oxirane cleavage of the epoxidized FAMEs by acetic acid were also studied.The conversion of ethylenic unsaturation group to oxirane, the reaction rate of the conversion to oxirane,and the rate of hydrolysis(oxirane cleavage)were higher by using the IL catalyst. 展开更多
关键词 in situ epoxidation kinetics oxirane cleavage unsaturated fatty acid methyl esters Brnsted acidic ionic liquids
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Effects of Yttrium Doping on the Performance of Ru-Based Catalysts for Hydrogenation of Fatty Acid Methyl Ester 被引量:1
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作者 Qi Lin Huirong Zheng +2 位作者 Guocai Zheng Xinzhong Li Benyong Lou 《International Journal of Organic Chemistry》 2014年第4期219-224,共6页
The highly dispersed supported ruthenium-yttrium (Ru-Y) bimetallic catalysts were prepared by impregnation method and their catalytic performance for hydrogenation of ester was fully investigated. The catalyst was cha... The highly dispersed supported ruthenium-yttrium (Ru-Y) bimetallic catalysts were prepared by impregnation method and their catalytic performance for hydrogenation of ester was fully investigated. The catalyst was characterized by X-ray diffraction and field emission scanning electron microscopy. The results show that the average particle diameter of the bimetallic crystallites was less than 10 nm. The effects of the reaction temperature, the hydrogen pressure, the amount of catalyst and the proportion of yttrium in catalyst on the hydrogenation of ester were studied. The experimental results show that the introduction of yttrium not only changed the chemical and textural properties of ruthenium-based catalyst but also controlled the formation of Ru-Y alloy. The Ru-Y catalyst (Ru-2%Y/TiO2) exhibited high catalytic activity and good selectivity towards the higher alcohols. Under optimal reaction conditions of 240°C and 5 MPa hydrogen pressure, the conversion of palm oil esters was above 93.4% while the selectivity towards alcohol was above 99.0%. 展开更多
关键词 Yttrium-Doped Ruthenium-Based Catalyst fatty acid methyl ester HYDROGENATION
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Ternary Liquid-Liquid Equilibrium for Systems of Fatty Acid Methyl Ester(Methyl Palmitate/Methyl Stearate)+Ethanol+Glycerol at Atmospheric Pressure
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作者 夏淑倩 罗慧娟 马沛生 《Transactions of Tianjin University》 EI CAS 2015年第5期392-399,共8页
Liquid-liquid equilibrium data of two ternary systems methyl palmitate+ethanol+glycerol and methyl stearate+ethanol+glycerol at(318.2 and 333.2)K and atmospheric pressure were measured. The values of distribution coef... Liquid-liquid equilibrium data of two ternary systems methyl palmitate+ethanol+glycerol and methyl stearate+ethanol+glycerol at(318.2 and 333.2)K and atmospheric pressure were measured. The values of distribution coefficient and selectivity were calculated, which indicates that glycerol can be separated from fatty acid ester by using ethanol as an extraction solvent. The consistency of the isothermal tie-line data were checked by the Othmer-Tobias equation. The correlation coefficients R2 are higher than 0.993,9 for all the fitted curves. The NRTL activity coefficient model was applied to the correlation of the measured tie-line data. The root mean square deviation(RMSD)values are less than 0.007 for all the systems, which shows a good predictive capability of this model for such systems. 展开更多
关键词 liquid-liquid phase equilibrium fatty acid methyl ester ETHANOL NRTL model BIODIESEL
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Boosted Biodegradability and Tribological Properties of Mineral Base Oil by Methyl Diethanolamine Fatty Acid Esters 被引量:2
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作者 Ding Jianhua Fang Jianhua +3 位作者 Chen Boshui Zhang Nan Fan Xingyu Zheng Zhe 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2018年第4期117-124,共8页
Methyl diethanolamine fatty acid esters, viz. methyl diethanolamine octanoate and methyl diethanolamine oleate,were prepared. Their impacts on the biodegradability and tribological properties of mineral base oil 400 S... Methyl diethanolamine fatty acid esters, viz. methyl diethanolamine octanoate and methyl diethanolamine oleate,were prepared. Their impacts on the biodegradability and tribological properties of mineral base oil 400 SN were evaluated by a tester for fast evaluating the biodegradability of lubricants and by a four-ball tester, respectively. The results showed that methyl diethanolamine octanoate and methyl diethanolamine oleate both could markedly promote the biodegradation of the oil and improved its tribological properties. The improvement of biodegradability was attributed to the enhanced growth and quantity of microbes by methyl diethanolamine fatty acid esters. The worn surfaces were analyzed by a scanning electron microscope(SEM) equipped with an energy dispersive spectrometer(EDS) and an X-ray photoelectron spectroscope(XPS). The results indicated that the enhancement of friction-reducing and anti-wear properties of the mineral oil was attributed to the formation of complicated boundary lubrication films composed of species such as Fe_2O_3, Fe_3O_4 and organic nitrogen-containing compounds with a structure of –C-N-or R-NH_2. 展开更多
关键词 BIODEGRADATION wear friction methyl DIETHANOLAMINE fatty acid esterS
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Synthesis and Crystal Structure of 4-(4,6-dimethoxyl -pyrimidin-2-yl)-3-thiourea Carboxylic Acid Methyl Ester 被引量:1
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作者 HUANG Jie SONG Ji-Rong REN Ying-Hui XU Kang-Zhen MA Hai-Xia 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2006年第2期168-172,共5页
The title compound 4-(4,6-dimethoxylpyrimidin-2-yl)-3-thiourea carboxylic acid methyl ester was synthesized by the reaction of 2-amino-4,6-dimethoxyl pyrimidine, potassium thiocyanate and methyl chloroformate in eth... The title compound 4-(4,6-dimethoxylpyrimidin-2-yl)-3-thiourea carboxylic acid methyl ester was synthesized by the reaction of 2-amino-4,6-dimethoxyl pyrimidine, potassium thiocyanate and methyl chloroformate in ethyl acetate. Single crystals suitable for X-ray measurement were obtained by recrystallization with the solvent of dimethyl formamide at the room temperature. The structure was characterized by elemental analysis and IR and determined by X-ray diffraction analysis' Crystallographic data: C9H12N4O4S, Mr = 272.29, monoclinic, space group C2/m with a = 1.6672(3), b = 0.66383(12), c = 1.1617(2) nm, β = 109.275(2)°, V = 1.2136(4) nm^3, Dc = 1.490 g/cm^3,μ = 0.281 mm^-1, F(000) = 568, Z = 4, R1 = 0.0341and wR2 = 0.1042. 展开更多
关键词 4-(4 6-dimethoxylpyrimidin-2-yl)-3-thiourea carboxylic acid methyl ester synthesis X-ray diffraction
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Synthesis and Crystal Structure of 2-[(4-Methoxy- 6-methylthio-2-pyrimidinyl)aminocarbonyl- aminosulfonyl] Benzoic Acid Methyl Ester
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作者 黄明智 王晓光 +2 位作者 毛春晖 黄路 宋海斌 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2004年第7期743-746,共4页
The title compound 2-[(4-methoxy-6-methylthio-2-pyrimidinyl)aminocarbonyl- aminosulfonyl]benzoic acid methyl ester (C15H16N4O6S2, Mr = 412.44) was obtained by the reaction of (4-methoxy-6-methylthio-2-pyrimidinyl)amin... The title compound 2-[(4-methoxy-6-methylthio-2-pyrimidinyl)aminocarbonyl- aminosulfonyl]benzoic acid methyl ester (C15H16N4O6S2, Mr = 412.44) was obtained by the reaction of (4-methoxy-6-methylthio-2-pyrimidinyl)amine with 2-methoxylcarbonylbenzene-sulfonylisocya- nate. The crystal is of monoclinic, space group P21/c with a =11.169(3), b = 9.508(3), c = 17.690(5) ? b = 91.593(5), Z = 4, V = 1877.9(10) 3, Dc = 1.459 g/cm3, F(000) = 856, m(MoKa) = 0.324 mm-1, R = 0.0690 and wR = 0.1368 for 3301 observed reflections (I > 2s(I)). The N(1)H…N(3) and N(2)H…O(4) hydrogen bonds can be observed. In the molecule the phenyl plane(I), pyrimi- din-2-yl-urea bridge plane(Ⅱ) and ester plane(Ⅲ) form three conjugated systems. 展开更多
关键词 crystal structure sulfonylurea herbicide 2-[(4-methoxy-6-methylthio-2- pyrimidinyl)aminocarbonylaminosulfonyl]benzoic acid methyl ester SYNTHESIS
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NiMoRe/HZSM-5催化剂的制备及其催化脂肪酸甲酯加氢脱氧
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作者 郭效博 江文夺 +3 位作者 侯文彪 赵平 徐俊明 刘朋 《林产化学与工业》 CAS CSCD 北大核心 2024年第2期119-126,共8页
使用浸渍法制备了5 kg NiMoRe/HZSM-5催化剂,结合X射线衍射(XRD)、扫描电子显微镜(SEM)、电感耦合等离子原子发射光谱(ICP-OES)等表征手段对催化剂进行理化性质分析,并对该催化剂用于硬脂酸甲酯加氢脱氧反应的最佳条件进行探究。研究结... 使用浸渍法制备了5 kg NiMoRe/HZSM-5催化剂,结合X射线衍射(XRD)、扫描电子显微镜(SEM)、电感耦合等离子原子发射光谱(ICP-OES)等表征手段对催化剂进行理化性质分析,并对该催化剂用于硬脂酸甲酯加氢脱氧反应的最佳条件进行探究。研究结果表明:相比3种商用催化剂,NiMoRe/HZSM-5中金属Ni具有较小颗粒,且分散均匀,BET比表面积(S_(BET))更大,为239.1 m^(2)/g,具有更好的催化活性。在温度260℃、0.3 g催化剂用量、反应时间4 h、初始H 2压力3 MPa的最优反应条件下,原料转化率和烷烃选择性均为100%,且催化剂稳定性较佳,第5次循环原料转化率仍高达96.1%,加氢脱氧(HDO)反应的选择性(S HDO/DCO),即HDO反应与脱羧脱羰(DCO)反应的比值由1.2降至0.56。将催化剂NiMoRe/HZSM-5用于脂肪酸甲酯无溶剂条件下的加氢脱氧反应放大实验后进行中试,采用2.8 L固定床对25 kg脂肪酸甲酯进行连续加氢性能评价,经过15循环后脂肪酸甲酯的转化率达到98%。 展开更多
关键词 脂肪酸甲酯 中试 加氢脱氧 烃基生物柴油
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气相色谱-氢火焰离子化测定脂肪酸甲酯的响应机理与定量规律
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作者 崔华玲 杨慧 +7 位作者 孙丽华 叶倩 丁晨红 王威利 季天荣 马蕾 曾坤宏 殷秋妙 《食品科学》 EI CAS CSCD 北大核心 2024年第13期49-57,共9页
针对国内外现行标准中气相色谱-氢火焰离子化检测器(gas chromatography-flame ionization detector,GCFID)测定脂肪酸甲酯(fatty acid methyl esters,FAME)定量方法的不足,本实验通过理论推导和实验验证,从仪器、色谱柱、分流比、标准... 针对国内外现行标准中气相色谱-氢火焰离子化检测器(gas chromatography-flame ionization detector,GCFID)测定脂肪酸甲酯(fatty acid methyl esters,FAME)定量方法的不足,本实验通过理论推导和实验验证,从仪器、色谱柱、分流比、标准物质方面系统研究利用GC-FID分析37种FAME的响应规律、理论模型及实验干扰因素,提出“质量系数”和“关联因子”概念,揭示实验关联因子(experimental relevance factors,FF_(E))和理论关联因子(theoretical relevance factors,FF_(T))的函数关系和等值性条件,并经多个实验证实了关联因子的稳定性,发现当脂肪酸碳数大于10时,可充分利用理论质量系数(theoretical quality coefficient,QC_(T))和FFT对FAME进行相对或绝对定量;当脂肪酸碳数小于10时,可以通过现配FAME标准物质等方法精确测定实验质量系数(experimental quality coefficient,QC_(E))和实验关联因子FFE,并用此校正FAME的量进行定量,不仅能够提高定量结果的准确性,而且能够增加标准物质的使用时效以及节省标准物质的使用量。 展开更多
关键词 脂肪酸甲酯 甲酯化 气相色谱-氢火焰离子化检测 质量系数 关联因子
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固相萃取-气相色谱-串联质谱技术测定船用残渣燃料油中酚类及脂肪酸甲酯类化合物
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作者 张子豪 谭智毅 +4 位作者 麦晓霞 林海 李全忠 刘莹峰 肖前 《分析科学学报》 CAS CSCD 北大核心 2024年第4期395-403,共9页
本文利用乙酸银修饰的氧化铝-硅胶材料制备固相萃取柱对船用残渣燃料油样品进行净化分离,结合气相色谱-串联质谱技术,使用DB-35 MS UI色谱柱分离,多反应监控模式,内标法定量测定酚类及脂肪酸甲酯(FAME)类化合物。对影响酚类和FAME类化... 本文利用乙酸银修饰的氧化铝-硅胶材料制备固相萃取柱对船用残渣燃料油样品进行净化分离,结合气相色谱-串联质谱技术,使用DB-35 MS UI色谱柱分离,多反应监控模式,内标法定量测定酚类及脂肪酸甲酯(FAME)类化合物。对影响酚类和FAME类化合物的进样方式、萃取溶剂的选择、固相萃取柱类型的选择以及淋洗和洗脱条件进行了优化,建立了船用残渣燃料油中酚类及FAME类化合物的测定方法。方法在浓度0.05~2.5μg/mL范围线性良好,具有检出限(0.1~1.2 mg/kg)和定量限(0.3~4.0 mg/kg)低,稳定性好和萃取效率高,以及基质效应不显著等优势。通过用不含目标物的空白燃料油配制0.10、0.50、2.50 mg/L浓度水平的试样考察方法的可靠性,获得满意的回收率(85.5%~115.4%)和相对标准偏差(RSD≤6.2%)。实验结果表明,建立的方法可实现船用残渣燃料油中酚类及FAME类化合物的有效检测。另外,劣质船用燃油存在不少的酚类和FAME类物质,高浓度苯酚、甲酚、二甲酚、对枯基苯酚、脂肪酸甲酯等物质可能是导致船舶油泵损坏的重要原因。 展开更多
关键词 船用残渣燃料油 酚类 脂肪酸甲酯 固相萃取-气相色谱-串联质谱法
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Production of biodiesel from palm fatty acid distillate using sulfonated-glucose solid acid catalyst:Characterization and optimization
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作者 Ibrahim M.Lokman Umer Rashid Yun Hin Taufiq-Yap 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第11期1857-1864,共8页
A palm fatty acid distillate (PFAD) has been used for biodiesel production. An efficient sulfonated-glucose acid catalyst (SGAC) was prepared by sulfonation to catalyze the esterification reaction. The effect of t... A palm fatty acid distillate (PFAD) has been used for biodiesel production. An efficient sulfonated-glucose acid catalyst (SGAC) was prepared by sulfonation to catalyze the esterification reaction. The effect of three variables i.e. methanol-to-PFAD molar ratio, catalyst amount and reaction time, on the yield of PFAD esters was studied by the response surface methodology (RSM). The optimum reaction conditions were: 12.2:1 methanol-to- PFAD molar ratio, 2.9% catalyst concentration and 134 rain of time as predicted by the RSM. The reaction under the optimum conditions resulted in 94.5% of the free fatty acid (FFA) conversion with 92.4% of the FAME yield. The properties of the PFAD esters were determined according to biodiesel standards. 展开更多
关键词 Palm fatty acid distillate (PFAD)5ulfonated-glucose solid acid catalystesterificationOptimizationPFAD methyl ester
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The Synthesis of Some Novel N-[α-(Isoflavone-7-O-) Acetyl]Amino Acid Derivatives 被引量:1
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作者 Peng LIU Jun Biao CHANG +2 位作者 Rong Feng CHEN Qiang WANG Jing Xi XIE (Henan Institute of Chemistry, Henan Academy of Science, Zhengzhou 450002 Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050) 《Chinese Chemical Letters》 SCIE CAS CSCD 2000年第5期391-394,共4页
A series of novel N-[α-(isoflavone-7-O-)acetyl] amino acid methyl esters were prepared from the efficient and regioselective alkylation of isoflavones with chloroacetyl amino acid derivatives under mild condition.
关键词 Isoflavone analogues N-[α-(isoflavone-7-O-)acetyl] amino acid methyl ester synthesis.
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Determination of the Fatty Acid Profile of Breast Milk from Nursing Mothers in Bungoma County, Kenya
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作者 Virate J. Kiprop Amy W. Girard +2 位作者 Lilian A. Gogo Mary N. Omwamba Symon M. Mahungu 《Food and Nutrition Sciences》 2016年第8期661-670,共10页
The fatty acid profile in breast milk of nursing mothers who participated in a Cohort for Vitamin A (COVA) study at the fourth and ninth month of lactation was investigated. Breast milk samples were collected by manua... The fatty acid profile in breast milk of nursing mothers who participated in a Cohort for Vitamin A (COVA) study at the fourth and ninth month of lactation was investigated. Breast milk samples were collected by manual expression and stored at - 20°C until analysis. The fat was extracted from the milk and methylated using the American Oil Chemists’ Society (AOCS) Official Methods with modifications. The separation, identification and quantification of the fatty acid methyl esters was performed by gas chromatography coupled with mass spectrometry (GC-MS). Fat contents of human milk increased significantly between the fourth and ninth month of lactation 0.38 and 1.21 mg·mL<sup>-1</sup> respectively;P 0.05) than the average percent of the total unsaturated FAs (48.93%). Similarly, at the 9th month the percentage average of the total saturated fatty acids (15.18%) was significantly lower (P < 0.05) than the average percent of the total unsaturated FAs (31.05%). The results obtained in this study demonstrated that the fat content in breast milk significantly increased in the 9th compared to the 4th month of lactation. The fatty profile was also significantly different with the omega 6 being the dominant at the 9th month compared with the omega - 9 being dominant at the 4th month of lactation. 展开更多
关键词 fatty acid Profile Breast Milk Nursing Mothers fatty acid methyl esters LACTATION
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采用Peng-Robinson方程和体积平移的脂肪酸甲酯液相密度预测
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作者 蔡凌霄 张钰婧 王晓坡 《西安交通大学学报》 EI CAS CSCD 北大核心 2023年第12期72-79,共8页
为了提高经典的Peng-Robinson立方型状态方程(PR方程)预测脂肪酸甲酯高压液相密度的精度,并为生物柴油的进一步工程应用提供可靠的密度预测方法,在对文献中发表的19种饱和脂肪酸甲酯和6种不饱和脂肪酸甲酯的常压液相密度实验数据进行收... 为了提高经典的Peng-Robinson立方型状态方程(PR方程)预测脂肪酸甲酯高压液相密度的精度,并为生物柴油的进一步工程应用提供可靠的密度预测方法,在对文献中发表的19种饱和脂肪酸甲酯和6种不饱和脂肪酸甲酯的常压液相密度实验数据进行收集的基础上,采用体积平移法对PR方程进行了修正。分析发现,体积平移量与所研究的脂肪酸甲酯中的碳原子数、双键数以及温度存在一定的规律,并获得了其定量关系式,得到了可以预测同系列脂肪酸甲酯液相密度的体积平移的PR方程(VTPR方程)。结果表明,利用所提VTPR方程计算得到的脂肪酸甲酯常压密度与实验数据的总体相对偏差为0.30%。将所提VTPR方程用于预测脂肪酸甲酯高压条件下的密度,预测值与实验数据的总体相对偏差为0.50%,可以满足实际工程的需要。 展开更多
关键词 脂肪酸甲酯 密度 体积平移 Peng-Robinson方程
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H89-2原油流动性改进剂的研究 被引量:13
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作者 邸进申 李英杰 +2 位作者 郑辉杰 张诚 张衍礼 《石油学报》 EI CAS CSCD 北大核心 1998年第2期103-106,共4页
应用流动性改进剂(化学添加剂)可改善原油的低温流动性能。本文以烯烃、脂肪酸烯基酯和烯基酰胺或烯基磺酸盐为主要原料,在含有自由基引发剂的溶液中,在温度55~85℃,压力5~9MPa,聚合3~8h合成了能降低原油凝点的流... 应用流动性改进剂(化学添加剂)可改善原油的低温流动性能。本文以烯烃、脂肪酸烯基酯和烯基酰胺或烯基磺酸盐为主要原料,在含有自由基引发剂的溶液中,在温度55~85℃,压力5~9MPa,聚合3~8h合成了能降低原油凝点的流动性改进剂H89-2(三元共聚物)。综合评定了H89-2改善青海原油低温流动性能的效果,在原油中加入15×10-5H89-2,可使凝点从31.5℃降至12℃;表观粘度(20℃)从5158.9mPas降至79.2mPas;屈服值从73.6Pa降至0Pa。探讨了H89-2的降凝作用机理。因为H89-2既含有适度的烷烃碳链,又含有两种极性不同的极性基因,所以对原油的适应性较强。 展开更多
关键词 原油 流动性 改进剂 原油改进剂 H89-2
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制备高碳醇用Cu-Zn-Zr催化剂的研究 被引量:16
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作者 刘寿长 苏运来 陈诵英 《催化学报》 SCIE EI CAS CSCD 北大核心 1999年第4期445-449,共5页
研究了制备高碳醇用新的催化体系CuZnZr.CuZnZr催化剂可用Cu(NO3)2,Zn(NO3)2,ZrOCl2和Na2CO3为原料,采用并流共沉淀法制备.研究结果表明,CuZnZr催化剂对脂肪酸甲酯加氢制备高碳脂... 研究了制备高碳醇用新的催化体系CuZnZr.CuZnZr催化剂可用Cu(NO3)2,Zn(NO3)2,ZrOCl2和Na2CO3为原料,采用并流共沉淀法制备.研究结果表明,CuZnZr催化剂对脂肪酸甲酯加氢制备高碳脂肪醇具有很高的活性.催化剂的活性测定结果及XRD和TPR表征结果表明,Cu和Zn都是该催化剂的活性组分,Cu0和ZnO是其活性物相,Zr组分以ZrO物相存在,对活性组分起着间隔分散作用.用ASAP2000型物理吸附仪测定了催化剂的比表面积、比孔容、孔结构和孔径分布。 展开更多
关键词 脂肪酸甲酯 加氢 高碳醇 催化剂
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气相色谱-质谱法测定食品中的反式脂肪酸 被引量:10
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作者 牛翠娇 史玉琴 +2 位作者 殷志萍 赵文 宋涛 《安徽农业科学》 CAS 北大核心 2011年第6期3649-3651,共3页
[目的]采用气相色谱-质谱联用技术定性定量分析食品中的反棕榈油酸、反油酸和反异油酸3种反式脂肪酸。[方法]从食品中提取的脂肪在碱性条件下甲酯化;Hp-INNOW ax(30 m×0.25 mm×0.25μm)毛细管柱上分离,经质谱检测器检测;通... [目的]采用气相色谱-质谱联用技术定性定量分析食品中的反棕榈油酸、反油酸和反异油酸3种反式脂肪酸。[方法]从食品中提取的脂肪在碱性条件下甲酯化;Hp-INNOW ax(30 m×0.25 mm×0.25μm)毛细管柱上分离,经质谱检测器检测;通过标准品的保留时间、与标准谱库对照的方法定性;采用外标法定量;通过相关公式计算出样品反式脂肪酸含量。[结果]反式脂肪酸甲酯及其异构体分离效果较好;在0.001~0.010 mg/m l浓度范围内线性良好(r〉0.999 5),相对标准偏差为0.648%~2.430%,方法回收率为89.1%~102.0%,3种反式脂肪酸甲酯的检出限分别为0.800、0.875、0.840μg/m。l[结论]该方法准确、可靠、简捷,适用于食品中主要反式脂肪酸的测定。 展开更多
关键词 反式脂肪酸 脂肪酸甲酯 气相色谱-质谱法 检测
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丙磺酸型碗状碳微球制备及在餐厨废油酯交换反应中的性能研究
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作者 薛媛 何水清 +1 位作者 袁红 周惠良 《化工新型材料》 CAS CSCD 北大核心 2024年第3期166-171,176,共7页
以碗状碳微球(BHC)为载体,合成了以烷基为磺酸基键合位点的丙磺酸型碗状碳微球(PA-CBHC-Si)。X射线光电子能谱仪、扫描电子显微镜和傅里叶变换红外光谱分析表明,三步改性分别逐步丰富BHC表面羧基(—COOH)、巯基(—SH)、磺酸基(—SO_(3)H... 以碗状碳微球(BHC)为载体,合成了以烷基为磺酸基键合位点的丙磺酸型碗状碳微球(PA-CBHC-Si)。X射线光电子能谱仪、扫描电子显微镜和傅里叶变换红外光谱分析表明,三步改性分别逐步丰富BHC表面羧基(—COOH)、巯基(—SH)、磺酸基(—SO_(3)H)官能团含量,且改性过程保留了载体的原始形貌。PA-CBHC-Si的酸密度高达8.5mmol/g,活性中心—SO_(3)H于300℃开始分解,具有良好的热稳定性。PA-CBHC-Si可作为煎炸废油与甲醇酯交换反应的催化剂,醇油摩尔比为16∶1,剂油比为0.02的催化体系于130℃反应4h,脂肪酸甲酯产率为84.53%。 展开更多
关键词 脂肪酸甲酯 碗状碳微球 丙磺酸 酸密度
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废弃油脂脂肪酸甲酯合成C_(22)-三酸三酯 被引量:6
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作者 黄泽恩 李剑 +3 位作者 周永生 王建浩 曾桂凤 王车礼 《中国油脂》 CAS CSCD 北大核心 2013年第11期51-55,共5页
以废弃油脂脂肪酸甲酯和马来酸二丁酯为原料,碘为催化剂,通过Diels-Alder反应合成增塑剂C22-三酸三酯。利用气质联用仪对废弃油脂脂肪酸甲酯组成进行了分析,利用红外光谱对产物进行了分析,利用紫外光谱对合成反应机理进行了研究。结果表... 以废弃油脂脂肪酸甲酯和马来酸二丁酯为原料,碘为催化剂,通过Diels-Alder反应合成增塑剂C22-三酸三酯。利用气质联用仪对废弃油脂脂肪酸甲酯组成进行了分析,利用红外光谱对产物进行了分析,利用紫外光谱对合成反应机理进行了研究。结果表明:废弃油脂脂肪酸甲酯中不饱和脂肪酸酯含量高达74.376%,其中亚油酸甲酯含量为39.647%;废弃油脂脂肪酸甲酯中的亚油酸甲酯与马来酸二丁酯反应合成C22-三酸三酯分两步进行:①亚油酸甲酯共轭化;②共轭亚油酸甲酯与马来酸二丁酯发生Diels-Alder反应。通过正交实验得到合成C22-三酸三酯的最优工艺条件为:废弃油脂脂肪酸甲酯中亚油酸甲酯与马来酸二丁酯摩尔比1∶1,反应温度260℃,反应时间8 h,碘用量为废弃油脂脂肪酸甲酯质量的0.7%;在最优条件下,C22-三酸三酯产率为89.9%。 展开更多
关键词 废弃油脂脂肪酸甲酯 C22-三酸三酯 Diels—Alder反应 共轭反应
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原油流动性改进剂H89-2的制备及应用研究 被引量:5
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作者 邸进申 张诚 +1 位作者 李英杰 张衍礼 《精细化工》 EI CAS CSCD 北大核心 1997年第3期19-22,共4页
含蜡原油流动性改进剂H89-2系三元共聚物。以烯烃、烯烃基脂肪酸酯和烯属不饱和酰胺或烯属磺酸盐为主要原料,在含自由基引发剂的溶剂中,温度:55~85℃;压力:5~9MPa;时间:3~8h共聚而成。综合评定表明:H89... 含蜡原油流动性改进剂H89-2系三元共聚物。以烯烃、烯烃基脂肪酸酯和烯属不饱和酰胺或烯属磺酸盐为主要原料,在含自由基引发剂的溶剂中,温度:55~85℃;压力:5~9MPa;时间:3~8h共聚而成。综合评定表明:H89-2对青海原油降凝、降粘、降屈服值效果显著,添加量150×10-6,原油凝点从31.5℃降至12℃;表观粘度从5158.9MPa·s降至79.2MPa·s;屈服值从73.6Pa降至0Pa。 展开更多
关键词 流动性 改进剂 含蜡原油 原油 助剂
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GC-MS技术在鉴定食源性致病菌研究中的应用 被引量:5
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作者 吕均 秦巧玲 +3 位作者 郭爱玲 梁高道 郑华英 粟婉媛 《食品科学》 EI CAS CSCD 北大核心 2008年第2期355-358,共4页
通过有机溶剂提取、TLC分离及GC-MS对食源性致病菌中常见的4个属9种19株病原菌的全细胞脂肪酸组分进行了分析。结果表明:沙门氏菌属、埃希氏菌属、弧菌属和志贺氏菌属全细胞脂肪酸组分都含有十四烷酸、十六烷酸和十八碳烯酸,这三种脂肪... 通过有机溶剂提取、TLC分离及GC-MS对食源性致病菌中常见的4个属9种19株病原菌的全细胞脂肪酸组分进行了分析。结果表明:沙门氏菌属、埃希氏菌属、弧菌属和志贺氏菌属全细胞脂肪酸组分都含有十四烷酸、十六烷酸和十八碳烯酸,这三种脂肪酸占总脂肪酸含量的90%左右,含量最高的是十六烷酸,含量在40%以上,其次是十八碳烯酸,含量在30%左右。脂肪酸组成在属间差异显著。大肠杆菌O157不含有十三烷酸和十五烷酸,副溶血弧菌不含有十二烷酸和十三烷酸,志贺氏菌含有特异性的环戊烷十三烷酸。这些特征可作为各个属分类鉴定的依据。模式菌株和地方菌株在含有双键的脂肪酸上,双键的位置有一定的差异,因此通过这些差异可以鉴定模式菌株与地方菌株。 展开更多
关键词 总离子流 脂肪酸甲脂 GC-MS 致病菌
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