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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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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 不饱和脂肪酸 酸性离子液体 催化剂 脂肪酸甲酯 反应动力学 环氧乙烷 过氧化氢 白细胞介素
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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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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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Electrospray Ionization Mass Spectra of Amino Acid Methyl Ester 5′-Phosphoramidates of 2′,3′-Isopropylideneuridine
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作者 CHEN Wei-zhu GAO Yu-xing +2 位作者 BAI Yong-gang HAN Da-xiong ZHAO Yu-fen 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2006年第6期732-737,共6页
Amino acid methyl ester phosphates were synthesized and determined by using positive-ion mode dectrospmy ionization mass spectrometry(ESIMS) in combination with multistage tandem mass spectrometry. The fragmentation... Amino acid methyl ester phosphates were synthesized and determined by using positive-ion mode dectrospmy ionization mass spectrometry(ESIMS) in combination with multistage tandem mass spectrometry. The fragmentation pathways were investigated, and it was observed that most fragment ions contained the phosphoryl group. It was interesting to observe that the fragmentation pathways of the protonated molecule show some differences when compared with those of the sodium ion adduct. The methoxy group of amino acid methyl ester can migrate from the carbonyl group to the phosphoryl group in the sodium ion adduct. 展开更多
关键词 ESIMS Fragmentation pathway Methoxy group rearrangement Pentacoordinated phosphorus intermediate Amino acid methyl ester 5'-phosphoramidate of nucleoside
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Study on the Total Synthesis of 3-Oxo-9β-Acetoxyilicic Acid─The Synthesis of 9β-Acetoxy-3(4),11(13)-Dien-5αH,7αH-12-Eudesmanoic Acid Methyl Ester
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作者 Jiong YANG Zbao Ming XIONG Yong Gang CREN and Yu Lin LI(National Laboratory of Applied Organic Chemistry and Institute of Organic Chemistry,ho University, Lanzhou 730000) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第12期0-0,共2页
The synthesis of 99-acetoxy-3(4), 11(13)-dien-5αH 7αH-12-eudesmanoic acid methyl ester (2) was achieved from oxycarvone. The key step is the p-toluenesulfonhydrazide assisted reductiv rearrangement reaction
关键词 The Synthesis of 9 H 7 H-12-Eudesmanoic acid methyl ester Dien-5 Study on the Total Synthesis of 3-Oxo-9 Acetoxyilicic acid Acetoxy-3
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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 棕榈酸甲酯 脂肪酸甲酯 硬脂酸甲酯 大气压力 三元液液平衡 甘油 乙醇 系统
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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 合成 晶体结构 2-[(4-甲氧基-6-甲硫基-2-嘧啶基)甲酰胺基氨基磺酰]安息香酸甲基酯 C15H16N4O6S2
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Recent Development on Zero-Phosphate Spray Dried Detergent Powders Incorporated with Palm C16 Methyl Ester Sulfonates
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作者 Parthiban Siwayanan Ting Young Kang +2 位作者 Ramlan Aziz Nooh Abu Bakar Shreeshivadasan Chelliapan 《China Detergent & Cosmetics》 2016年第3期42-53,共12页
关键词 甲酯磺酸盐 表面活性剂 化工行业 发展现状
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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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催化剂酸碱性与催化酯醛缩合性能的关系
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作者 张伟 贾鑫 +3 位作者 王兴永 孙培永 傅送保 姚志龙 《精细化工》 EI CAS CSCD 北大核心 2024年第3期687-696,共10页
以γ-Al_(2)O_(3)和SiO_(2)为载体,采用浸渍法引入不同含量Na^(+)、K^(+)和Cs+碱金属离子,制备了一系列酯醛气相缩合催化剂。利用XRD、BET、NH3-TPD和CO_(2)-TPD对催化剂的结构和表面酸、碱性进行了表征,并以丙酸甲酯与甲醛为原料,考察... 以γ-Al_(2)O_(3)和SiO_(2)为载体,采用浸渍法引入不同含量Na^(+)、K^(+)和Cs+碱金属离子,制备了一系列酯醛气相缩合催化剂。利用XRD、BET、NH3-TPD和CO_(2)-TPD对催化剂的结构和表面酸、碱性进行了表征,并以丙酸甲酯与甲醛为原料,考察了其催化酯醛气相缩合反应性能。结果表明,在0.2 MPa、370℃和质量空速为1.2 h^(-1)的条件下,以10%(以载体SiO_(2)质量为基准,下同)Cs/SiO_(2)为催化剂时,丙酸甲酯转化率最高(41.03%),甲基丙烯酸甲酯选择性为99.20%。在有丰富碱活性中心的前提下,催化剂表面弱碱性位点含量与其催化酯醛气相缩合反应性能呈正相关关系,催化剂表面酸性位点和中强碱性位点的存在会导致催化剂催化活性和选择性的降低。 展开更多
关键词 酯醛缩合 催化剂 酸性 碱性 丙酸甲酯 精细化工中间体
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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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荆条的化学成分研究
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作者 张梓萌 金戈 胡苹 《沈阳医学院学报》 2024年第4期400-403,共4页
目的:研究荆条(Vitex.negundo var.heterophylla)的化学成分。方法:采用溶剂萃取法,硅胶、ODS、Sephadex LH-20以及半制备型HPLC等多种柱色谱分离方法进行分离纯化,通过理化常数测定、波谱数据分析鉴定化合物的结构。结果:从荆条叶、种... 目的:研究荆条(Vitex.negundo var.heterophylla)的化学成分。方法:采用溶剂萃取法,硅胶、ODS、Sephadex LH-20以及半制备型HPLC等多种柱色谱分离方法进行分离纯化,通过理化常数测定、波谱数据分析鉴定化合物的结构。结果:从荆条叶、种子的95%乙醇提取物中分离得到5个化合物,分别鉴定为5,4'-二羟基-3,6,7-三甲氧基黄酮、5,4'-二羟基-3,6,7,8-四甲氧基黄酮、对羟基苯甲醛、对羟基苯甲酸、对羟基苯甲酸甲酯。结论:通过对荆条的化学成分进行研究,丰富了荆条的化学组成及其可能发挥药效的物质基础。 展开更多
关键词 荆条 牡荆属 5 4'-二羟基-3 6 7-三甲氧基黄酮 5 4'-二羟基-3 6 7 8-四甲氧基黄酮 对羟基苯甲酸甲酯
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Chemical profiling of bioactive compounds in the methanolic extract of wild leaf and callus of Vitex negundo using gas chromatographymass spectrometry
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作者 Gunjan Garg Alok Bharadwaj +1 位作者 Shweta Chaudhary Veena Gupta 《World Journal of Experimental Medicine》 2024年第1期78-87,共10页
BACKGROUND The investigation of plant-based therapeutic agents in medicinal plants has revealed their presence in the extracts and provides the vision to formulate novel techniques for drug therapy.Vitex negundo(V.neg... BACKGROUND The investigation of plant-based therapeutic agents in medicinal plants has revealed their presence in the extracts and provides the vision to formulate novel techniques for drug therapy.Vitex negundo(V.negundo),a perennial herb belonging to the Varbanaceae family,is extensively used in conventional medication.AIM To determine the existence of therapeutic components in leaf and callus extracts from wild V.negundo plants using gas chromatography-mass spectrometry(GCMS).METHODS In this study,we conducted GC-MS on wild plant leaf extracts and correlated the presence of constituents with those in callus extracts.Various growth regulators such as 6-benzylaminopurine(BAP),2,4-dichlorophenoxyacetic acid(2,4-D),α-naphthylacetic acid(NAA),and di-phenylurea(DPU)were added to plant leaves and in-vitro callus and grown on MS medium.RESULTS The results clearly indicated that the addition of BAP(2.0 mg/L),2,4-D(0.2 mg/mL),DPU(2.0 mg/L)and 2,4-D(0.2 mg/mL)in MS medium resulted in rapid callus development.The plant profile of Vitex extracts by GC-MS analysis showed that 24,10,and 14 bioactive constituents were detected in the methanolic extract of leaf,green callus and the methanolic extract of white loose callus,respectively.CONCLUSION Octadecadienoic acid,hexadecanoic acid and methyl ester were the major constituents in the leaf and callus methanolic extract.Octadecadienoic acid was the most common constituent in all samples.The maximum concentration of octadecadienoic acid in leaves,green callus and white loose callus was 21.93%,47.79%and 40.38%,respectively.These findings demonstrate that the concentration of octadecadienoic acid doubles in-vitro compared to in-vivo.In addition to octadecadienoic acid;butyric acid,benzene,1-methoxy-4-(1-propenyl),dospan,tridecanedialdehyde,methylcyclohexenylbutanol,chlorpyrifos,n-secondary terpene diester,anflunine and other important active compounds were also detected.All these components were only available in callus formed in-vitro.This study showed that the callus contained additional botanical characteristics compared with wild plants.Due to the presence of numerous bioactive compounds,the medical use of Vitex for various diseases has been accepted and the plant is considered an important source of therapeutics for research and development. 展开更多
关键词 Leaf extracts Callus extracts Methanolic extract Octadecadienoic acid Hexadecanoic acid methyl ester Gas chromatography-mass spectrometry analysis
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The Role of Jasmonates as Antibulbing Substances in the Bulb Formation of Onion
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作者 Noboru Takada Atsushi Saito +4 位作者 Yuuki Matsuzuka Tatsushi Mochiduki Eriko Wakita Meng WANG Yasunori Koda 《Agricultural Biotechnology》 2024年第1期1-4,8,共5页
Onion plants form spherical bulbs under long-day conditions.Substances regulating bulb formation remain unknown.In the course of chemical studies on the bulb formation,α-linolenic acid was isolated from onion extract... Onion plants form spherical bulbs under long-day conditions.Substances regulating bulb formation remain unknown.In the course of chemical studies on the bulb formation,α-linolenic acid was isolated from onion extracts as an antibulbing substance,the amount of which was synchronized with the bulb formation.Since allene oxide synthase inhibitor canceled the antibulbing activity ofα-linolenic acid,it was disclosed that jasmonic acid concerns this regulation.Structure-activity-relationship study revealed that its(3R,7S)stereochemistry is necessary for showing its antibulbing activity.It is concluded that(3R,7S)-jasmonate derived fromα-linolenic acid actually participates in the regulation of bulb formation. 展开更多
关键词 Onion(Allim cepa L.cv.Higuma) ISOLATION Bulb formation Antibulbing substance α-linolenic acid methyl jasmonate
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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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超临界CO_(2)萃取石榴籽油及石榴酸甲酯富集
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作者 任小娜 李兴梅 +1 位作者 吴江超 库尔班江·艾买提 《食品研究与开发》 CAS 2024年第8期85-90,共6页
采用超临界CO_(2)萃取技术从石榴籽中提取石榴籽油,对其脂肪酸和甘三酯组成和含量进行分析;通过单因素和正交优化试验研究尿素包合法富集石榴酸甲酯。超临界CO_(2)萃取技术与有机溶剂萃取相比更有利于获得高石榴酸含量的石榴籽油,石榴... 采用超临界CO_(2)萃取技术从石榴籽中提取石榴籽油,对其脂肪酸和甘三酯组成和含量进行分析;通过单因素和正交优化试验研究尿素包合法富集石榴酸甲酯。超临界CO_(2)萃取技术与有机溶剂萃取相比更有利于获得高石榴酸含量的石榴籽油,石榴籽油中检测出14种甘三酯。尿素包合法富集石榴酸甲酯的最佳工艺为尿素包合温度5℃、包合时间20 h、尿素与脂肪酸甲酯的质量比1∶1、尿素和95%乙醇的质量比1∶5,此最佳包合条件下获得的石榴酸甲酯的含量为78.82%。 展开更多
关键词 石榴籽油 石榴酸甲酯 尿素包合 石榴酸 超临界CO_(2)
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蛋白核小球藻原位催化制备生物柴油的研究
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作者 刘欢 王一同 郭璇 《当代化工研究》 CAS 2024年第6期162-164,共3页
化石燃料是全球能源供应的主要来源,在过去的几十年里,由于人口和能源需求的增加,导致能源消耗和CO_(2)排放量迅速增加,加剧了全球气候变化。利用生长迅速、含油量高、对环境友好的蛋白核小球藻(Chlorella pyrenoidosa)催化转化生物柴... 化石燃料是全球能源供应的主要来源,在过去的几十年里,由于人口和能源需求的增加,导致能源消耗和CO_(2)排放量迅速增加,加剧了全球气候变化。利用生长迅速、含油量高、对环境友好的蛋白核小球藻(Chlorella pyrenoidosa)催化转化生物柴油具有很大发展潜力,可以实现“碳中和”及可持续发展。传统的两步酯交换法制备生物柴油在经济环境上是不可行的,脱水干燥和脂质提取过程消耗了大量能源和成本,采用“一步”原位酯交换方法替代传统的两步酯交换将微藻转化为低成本高附加值产品,可以实现高生物柴油产率及高C16、C18脂肪酸甲酯组分含量,产生高质量的生物柴油,具有生态和经济效益。 展开更多
关键词 蛋白核小球藻 原位酯交换 生物柴油 脂肪酸甲酯 均相酸催化剂
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溶剂分离法提取生物柴油中的不饱和脂肪酸甲酯
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作者 平原 李寅 +2 位作者 申夏夏 马敏 钱玲玲 《生物化工》 CAS 2024年第3期111-114,共4页
为了降低生物柴油的冷凝点,采用溶剂分离法提取生物柴油中的不饱和脂肪酸甲酯,重点考察了醇的种类、溶剂的用量、冷冻温度和过滤方式对分离效果的影响。结果表明:乙醇的用量为原料质量的2~3倍,冷冻温度-15℃,压滤法过滤,最高可得到96.95... 为了降低生物柴油的冷凝点,采用溶剂分离法提取生物柴油中的不饱和脂肪酸甲酯,重点考察了醇的种类、溶剂的用量、冷冻温度和过滤方式对分离效果的影响。结果表明:乙醇的用量为原料质量的2~3倍,冷冻温度-15℃,压滤法过滤,最高可得到96.9575%的不饱和脂肪酸甲酯含量和86.92%的得率。 展开更多
关键词 溶剂分离法 生物柴油 不饱和脂肪酸甲酯 生物柴油降凝
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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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