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Different characteristics of 40 kinds of free amino acids and 5-amino levulinic acid between wines and sakes(Japanese rice wines)
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作者 Tohru Kimura 《Journal of Future Foods》 2024年第4期361-368,共8页
Based on a systemic analysis for the globa1 burden of disease study from 1990 to 2016,the Global Burden of Diseases(GBD)2016 Alcohol Collaborators reported that alcohol use was a 1eading nisk factor for globa1 disease... Based on a systemic analysis for the globa1 burden of disease study from 1990 to 2016,the Global Burden of Diseases(GBD)2016 Alcohol Collaborators reported that alcohol use was a 1eading nisk factor for globa1 disease burden and caused substantial health loss.However,alcoholic dnink(wines and sakes)contains abundant nutrients,particularly fermentable amino acids denived from grapes and rice.Amino acid nutrition and metabolism is strongly associated with health and preventiom against various diseases.The purpose of this study was to elucidate 40 kinds of free amino acid(FAA)profles in wines and sakes.In addition,the present study also provided the contents of 5-aminolevulinic acid(5-AI A)involved in the vital functionality of mitochondria.FAAs were detected and analyzed by use of an automatic amino acid analyzer.Aromatic amino acid,branched chain amino acid and Fischer ratio were calculated for each beverage.Individua1 FAAs showed significant differences between wines and sakes.Sakes abundantly contained almost all FAAs whereas wines had just a lttle content in some FAAs.Sakse were rich in arginine,glycine,alanine,valine,glutamic acid and leucine,while wines were remarkably nich in proline(Pro).Wines showed increased FAA levels in 6 kinds of variables(4-hydroxyproline,3-methy1 histidine,B-alanine,a-aminobutyric acid,Pro and a.-aminoadipic acid).In functionally characteristic FAAs,both wines and sakes were considerably abundant in y aminobutynic acid and 5-AI A The total amount of aromatic amino acid and branched chain amino acid were markedly higher in sakes than in wines.These results revealed that there were the apparent different characteristics in FAA profiles between wines and sakes.This difference resulted from fermentation process in wines(single fermentation)and sakes(paralle1 double fermentation).Forty kinds of FAA profiles are more usefu1 in investigating characteristics of the taste of wines and sakes.In future,detailed FAA analysis has the potential to find functional nutrients such as 5-AI A,whereas other foods generally contain ittle amount of these FAAs. 展开更多
关键词 FERMENTATION 5-amino levulinic acid Free anino acids γ-aminobutyric acid Sake WINE
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Synthetic Approach for Novel Fluorine Substituted <i>α</i>-Aminophosphonic Acids Containing 1,2,4-Triazin-5-One Moiety as Antioxidant Agents
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作者 Mohammed S. T. Makki Reda M. Abdel-Rahman Abdulrahman S. Alharbi 《International Journal of Organic Chemistry》 2018年第1期1-15,共15页
Novel fluorine substituted α-amino phosphonic acids containing 1,2,4-triazin- 5-one (6a-f) have been obtained from fluoroacylation of 6-(2&prime;-amino-5&prime;-nitrophenyl)-3-thioxo-1,2,4-triazin-5(4H)-one (... Novel fluorine substituted α-amino phosphonic acids containing 1,2,4-triazin- 5-one (6a-f) have been obtained from fluoroacylation of 6-(2&prime;-amino-5&prime;-nitrophenyl)-3-thioxo-1,2,4-triazin-5(4H)-one (1) followed by ammonilysis to give the corresponding 3-amino-derivative 3. Condensation of compound 3 with nitro/halogenated aromatic aldehydes yielded the Schiff bases 4. The simple addition of diethyl phosphonate to compound 4 produced the α-amino phosphonates 5. Acidic hydrolysis of compound 5 produced the fluorine substituted α-amino acids derivatives 6. Structures of the new compounds have been established with the help of elemental analysis and spectral measurements. Also, the products evaluated as antioxidants, where the fluorinated α-amino phosphonic acids 6 are more active than the other synthesized systems. 展开更多
关键词 Synthetic FLUORINE α-amino acids 1 2 4-Triazin-5-One MOIETY ANTIOXIDANTS Activity
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Production of octyl levulinate biolubricant over modified H-ZSM-5:Optimization by response surface methodology 被引量:1
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作者 Kakasaheb Y.Nandiwale Sunil K.Yadava Vijay V.Bokade 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2014年第4期535-541,共7页
The present study highlighted the use of modified H-ZSM-5 (Meso-HZ-5) as heterogeneous catalyst for the synthesis of octyl levulinate biolubricant by catalytic esterification of biomass derived renewable levulinic a... The present study highlighted the use of modified H-ZSM-5 (Meso-HZ-5) as heterogeneous catalyst for the synthesis of octyl levulinate biolubricant by catalytic esterification of biomass derived renewable levulinic acid (LA) with n-octanol. The process variables such as catalyst loading (X1), n-octanol to LA molar ratio (X2) and reaction temperature (X3) were optimized through response surface methodology (RSM), using Box-Behnken model. Analysis of variance was performed to determine the adequacy and significance of the quadratic model. The yield of octyl levulinate was obtained to be 99% at optimum process parameters. The developed quadratic model was found to be adequate and statistically accurate with correlation value (R2) of 0.9971 to predict the yield of octyl levulinate biolubricant. The study was also extended on the validation of theoretical and experimental data, including catalyst reusability. 展开更多
关键词 biolubricant ESTERIFICATION H-ZSM-5 levulinic acid octyl levulinate response surface methodology
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Synthesis and Characterization of Rare Earth Solid Complexes with Sodium 5-Aminosalicylate
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作者 张秀英 李书静 +1 位作者 雷雪峰 马君现 《Journal of Rare Earths》 SCIE EI CAS CSCD 2005年第2期143-147,共5页
Ten new rare earth solid complexes were synthesized by the reaction of sodium 5-aminosalicyliate with rare earth chloride. The structure character, physical and chemical properties of these complexes were studied by I... Ten new rare earth solid complexes were synthesized by the reaction of sodium 5-aminosalicyliate with rare earth chloride. The structure character, physical and chemical properties of these complexes were studied by IR, UV, ()~1H NMR spectra, TG-DTA, fluorescence, elemental analyses, molar conductance and magnetic susceptibility. The ten rare earth complexes exist in dimeric form probably and the coordination number is seven. The antibacterial activity of the ligand and six complexes was also tested against Staphylococcus aureus, Escherichia coli and Bacillus subtilis, and the effect of Yb complex at 20 mg·ml^(-1) against Staphylococcus aureus is most significant. 展开更多
关键词 rare earth complexes 5-amino salicylic acid antibacterial activity
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5-羟甲基糠醛在稀硫酸催化下的降解反应动力学 被引量:18
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作者 彭新文 吕秀阳 《化工学报》 EI CAS CSCD 北大核心 2008年第5期1150-1155,共6页
5-羟甲基糠醛脱羧生成乙酰丙酸是生物质资源出发制备乙酰丙酸过程中的关键步骤之一。为了研究低硫酸浓度下水解生物质制备乙酰丙酸工艺的可行性,系统地测定了在压力5MPa、初始浓度1~9mg.ml-1、硫酸浓度0.05%~0.4%(质量分数)、温度150... 5-羟甲基糠醛脱羧生成乙酰丙酸是生物质资源出发制备乙酰丙酸过程中的关键步骤之一。为了研究低硫酸浓度下水解生物质制备乙酰丙酸工艺的可行性,系统地测定了在压力5MPa、初始浓度1~9mg.ml-1、硫酸浓度0.05%~0.4%(质量分数)、温度150~190℃条件下,5-羟甲基糠醛在稀硫酸催化下的降解反应动力学数据,并以主反应生成乙酰丙酸、副反应生成腐黑质的平行反应动力学模型对数据进行了拟合,拟合结果表明,在实验范围内,主、副反应对5-羟甲基糠醛均为一级反应;主反应对H+浓度为1.16级,反应的活化能为78.5kJ.mol-1;副反应对H+浓度为0.722级,反应的活化能为98.0kJ.mol-1。研究结果表明,降低温度和提高硫酸浓度有利于提高生成乙酰丙酸的选择性。 展开更多
关键词 5-羟甲基糠醛 乙酰丙酸 稀硫酸 降解 动力学
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5-羟基乙酰丙酸的内酯化与缩聚反应 被引量:5
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作者 张艳 吴林波 +1 位作者 李枫 李伯耿 《化工学报》 EI CAS CSCD 北大核心 2006年第4期992-996,共5页
以乙酰丙酸(LA)为原料,通过改进的溴化、水解反应,合成5羟基乙酰丙酸(5HLA).基于5HLA的羟基和羧基,将其作为单体,氯化亚锡为催化剂,经缩聚得到了一种新的脂肪族聚酯———聚5羟基乙酰丙酸(PHLA).另以BF3·OEt2为催化剂,进行5HLA的... 以乙酰丙酸(LA)为原料,通过改进的溴化、水解反应,合成5羟基乙酰丙酸(5HLA).基于5HLA的羟基和羧基,将其作为单体,氯化亚锡为催化剂,经缩聚得到了一种新的脂肪族聚酯———聚5羟基乙酰丙酸(PHLA).另以BF3·OEt2为催化剂,进行5HLA的内酯化反应,得到了二聚体1,6,9,13四氧双螺[4.2.4.2]十四烷2,10二酮(又称阿尔泰内酯),它是中药九节菖蒲的化学成分之一.分别用气质联用、核磁、红外、元素分析和凝胶渗透色谱等方法对所得二聚体以及聚合物结构进行表征,讨论了有关的反应机理. 展开更多
关键词 5-羟基乙酰丙酸 乙酰丙酸 脂肪族聚酯 缩聚 阿尔泰内酯
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生物质生产乙酰丙酸及其衍生物5-氨基乙酰丙酸的进展 被引量:6
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作者 陈育如 骆跃军 李雪梅 《林产化学与工业》 EI CAS CSCD 2006年第3期113-117,共5页
基于生物质资源的利用和开发,论述了乙酰丙酸的制取、5-氨基乙酰丙酸的化学合成与生物合成,阐述了其在医药、农业等方面的应用,讨论了发展趋势和亟待解决的问题。
关键词 生物质 乙酰丙酸 5-氨基乙酰丙酸
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乙酰丙酸和前体物对Rhodobacter sphaeroides 5-氨基乙酰丙酸合成的影响 被引量:7
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作者 王俊卿 张肇铭 《应用与环境生物学报》 CAS CSCD 北大核心 2005年第5期611-613,共3页
球形红细菌Rhodobacter sphaeroides光合成培养过程中(接种量2g/L),分别以不同方式加入不同浓度的乙酰丙酸(LA)、前体物(甘氨酸、琥珀酸),发现LA(30mmol/L)分3次加入,甘氨酸(60mmol/L)分2次加入,可使5-氨基乙酰丙酸合成酶(ALAS)的活性(1... 球形红细菌Rhodobacter sphaeroides光合成培养过程中(接种量2g/L),分别以不同方式加入不同浓度的乙酰丙酸(LA)、前体物(甘氨酸、琥珀酸),发现LA(30mmol/L)分3次加入,甘氨酸(60mmol/L)分2次加入,可使5-氨基乙酰丙酸合成酶(ALAS)的活性(149.1U/mg)提高,而其脱水酶(ALAD)活性(143.4U/mg)降低,使ALA产量提高到33.8mmol/L. 展开更多
关键词 RHODOBACTER SPHAEROIDES 5-氨基乙酰丙酸 乙酰丙酸 甘氨酸
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固体酸催化5-羟甲基糠醛的降解动力学研究 被引量:3
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作者 曾珊珊 林鹿 刘娣 《林产化学与工业》 EI CAS CSCD 北大核心 2013年第4期32-36,共5页
利用小型高压反应釜测定了温度在423.15~463.15 K范围内无催化、固体酸SO42-/ZrO2-TiO2和SO42-/ZrO2催化下5-羟甲基糠醛的分解反应动力学数据。结果表明,反应时间、反应温度和固体酸催化剂显著影响了5-羟甲基糠醛的转化和乙酰丙酸的产... 利用小型高压反应釜测定了温度在423.15~463.15 K范围内无催化、固体酸SO42-/ZrO2-TiO2和SO42-/ZrO2催化下5-羟甲基糠醛的分解反应动力学数据。结果表明,反应时间、反应温度和固体酸催化剂显著影响了5-羟甲基糠醛的转化和乙酰丙酸的产率。用一级反应动力学方程拟合实验数据,得到本实验中无催化、固体酸SO24-/ZrO2-TiO2和SO42-/ZrO2催化下5-羟甲基糠醛分解反应的表观活化能分别为106.4、73.42和77.04 kJ/mol。固体酸的加入可以大大提高了5-羟甲基糠醛的转化率,同时提高乙酰丙酸的产率。 展开更多
关键词 5-羟甲基糠醛 乙酰丙酸 固体酸 分解 反应动力学
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可降解共聚酯聚(5-羟基乙酰丙酸-co-D,L-乳酸)的合成与表征 被引量:2
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作者 张艳 郭正虹 +1 位作者 程捷 方征平 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2009年第5期8-11,共4页
以5-羟基乙酰丙酸(5-HLA)和D,L-乳酸(DLLA)为原料通过熔融缩聚合成一种新型脂肪族共聚酯——聚(5-羟基乙酰丙酸-co-D,L乳酸)(PHLA-DLLA)。利用凝胶渗透色谱(GPC)、红外分析(FT-IR)和差示量热扫描(DSC)等方法对所得聚合物的分子量、结构... 以5-羟基乙酰丙酸(5-HLA)和D,L-乳酸(DLLA)为原料通过熔融缩聚合成一种新型脂肪族共聚酯——聚(5-羟基乙酰丙酸-co-D,L乳酸)(PHLA-DLLA)。利用凝胶渗透色谱(GPC)、红外分析(FT-IR)和差示量热扫描(DSC)等方法对所得聚合物的分子量、结构以及热性能进行了表征。通过改变反应条件,可获得重均分子量1390~9920、玻璃化温度38.3℃~71.8℃的共聚产物。结果表明,乳酸用量的增加有利于提高共聚物的分子量;而共聚物PHLA链节中的氢键作用能够提高共聚物的玻璃化温度。 展开更多
关键词 5-羟基乙酰丙酸 乙酰丙酸 脂肪族聚酯 缩聚 可降解
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ZSM-5催化葡萄糖清洁转化合成乙酰丙酸 被引量:10
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作者 隋小玉 林鹿 《化学反应工程与工艺》 CAS CSCD 北大核心 2010年第1期74-78,87,共6页
研究了以沸石分子筛ZSM-5为催化剂,水解葡萄糖制备乙酰丙酸的反应,探讨了催化剂用量、反应温度、反应时间对乙酰丙酸得率的影响。结果表明,在催化剂用量3 g、温度190℃、反应时间2.5 h的条件下,乙酰丙酸的最大摩尔得率可达到67.54%。通... 研究了以沸石分子筛ZSM-5为催化剂,水解葡萄糖制备乙酰丙酸的反应,探讨了催化剂用量、反应温度、反应时间对乙酰丙酸得率的影响。结果表明,在催化剂用量3 g、温度190℃、反应时间2.5 h的条件下,乙酰丙酸的最大摩尔得率可达到67.54%。通过X射线衍射(XRD)和X射线光电子能谱(XPS)分析了催化剂在反应前后的结构变化,发现催化剂表面结焦积炭是失活的主要原因。通过焙烧除去失活催化剂表面的积碳后进行催化反应,使得产物乙酰丙酸摩尔得率可达到57.02%。 展开更多
关键词 乙酰丙酸 葡萄糖 ZSM-5沸石分子筛
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以乙酰丙酸为原料合成5-羟基乙酰丙酸的研究 被引量:1
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作者 张艳 吴林波 +2 位作者 李枫 卜志扬 李伯耿 《浙江大学学报(工学版)》 EI CAS CSCD 北大核心 2006年第11期1895-1899,1917,共6页
对新型聚酯单体5-羟基乙酰丙酸(5-HLA)的合成工艺进行了改进和优化.以来源于生物质资源的乙酰丙酸(LA)为原料,通过改进的溴化和水解反应合成了5-HLA.优化溴化反应温度、液溴滴加速率、反应介质用量等溴化反应条件;同时利用3-溴乙酰丙酸... 对新型聚酯单体5-羟基乙酰丙酸(5-HLA)的合成工艺进行了改进和优化.以来源于生物质资源的乙酰丙酸(LA)为原料,通过改进的溴化和水解反应合成了5-HLA.优化溴化反应温度、液溴滴加速率、反应介质用量等溴化反应条件;同时利用3-溴乙酰丙酸甲酯等溴化物的分子内重排和歧化反应,对溴化反应生成的副产物回收再利用,将中间产物5-溴乙酰丙酸甲酯的产率从文献值30%提高到45%.5-溴乙酰丙酸甲酯经一步水解、乙醚连续萃取和重结晶得到5-HLA.改进后的工艺基于乙酰丙酸的产率为30%,与二步法相比,操作时间短,产率大大提高. 展开更多
关键词 乙酰丙酸 溴化 5-溴乙酰丙酸甲酯 5-羟基乙酰丙酸
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废纸纤维近临界水解获取5-羟甲基糠醛的研究 被引量:1
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作者 连洁 王艳 +1 位作者 万金泉 马邕文 《太阳能学报》 EI CAS CSCD 北大核心 2015年第8期1952-1958,共7页
以废纸纤维为原料,研究温度、反应时间、原料浓度、反应压力对废纸纤维近临界水解获取5-羟甲基糠醛(5-HMF)的影响,同时考察前驱物六碳糖和水解副产物乙酰丙酸对5-HMF生成和降解的影响。最优水解条件显示:近临界温度为375℃、反应时间为2... 以废纸纤维为原料,研究温度、反应时间、原料浓度、反应压力对废纸纤维近临界水解获取5-羟甲基糠醛(5-HMF)的影响,同时考察前驱物六碳糖和水解副产物乙酰丙酸对5-HMF生成和降解的影响。最优水解条件显示:近临界温度为375℃、反应时间为200 s、原料浓度为2.4%、反应压力为19.2 MPa时,获得的5-HMF产率最大,为(10.92±0.51)%。相比原生废纸纤维,其水解残渣的结晶度由69.24%降为57.14%,残渣中仍存在一定量的纤维素,纤维素结晶结构带来的反应屏障是影响5-HMF产率的一个重要因素。 展开更多
关键词 废纸纤维 近临界水解 5-羟甲基糠醛 六碳糖 乙酰丙酸 结晶结构
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5-羟甲基糠醛与乙酰丙酸制备生物基化学品的研究进展 被引量:7
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作者 朱仕林 李静丹 +3 位作者 姜小祥 杨宏旻 蒋剑春 张爱玲 《生物质化学工程》 CAS 北大核心 2016年第4期53-59,共7页
综述了生物质基平台分子5-羟甲基糠醛及乙酰丙酸转化制备多种化学品的研究进展,主要包括5-羟甲基糠醛转化为2,5-呋喃二甲酸、2,5-呋喃二甲醛、2,5-二甲基呋喃的过程以及乙酰丙酸转化为酯类、酸类、吡咯烷酮及双酚酸。简要介绍了这几种... 综述了生物质基平台分子5-羟甲基糠醛及乙酰丙酸转化制备多种化学品的研究进展,主要包括5-羟甲基糠醛转化为2,5-呋喃二甲酸、2,5-呋喃二甲醛、2,5-二甲基呋喃的过程以及乙酰丙酸转化为酯类、酸类、吡咯烷酮及双酚酸。简要介绍了这几种生物基化学品的用途、生产工艺以及其中存在的问题,旨在为发展从生物质平台分子制备生物基化学品的工业生产提供指导意义。 展开更多
关键词 5-羟甲基糠醛 乙酰丙酸 化学品
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ZrOCl2催化琼脂糖制备5-羟甲基糠醛和乙酰丙酸 被引量:1
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作者 何欣骏 马娇 +2 位作者 王康军 许占威 贾松岩 《生物质化学工程》 CAS 北大核心 2019年第5期15-20,共6页
以琼脂糖为原料,分别采用CuCl2、NiCl2、MnCl2、MgCl2、FeCl3、AlCl3、ZrOCl2、SnCl4为催化剂催化转化制备5-羟甲基糠醛(5-HMF)和乙酰丙酸(LA),筛选适用于琼脂糖转化的优选催化剂,并对制备条件如溶剂含水量、催化剂用量、反应温度以及... 以琼脂糖为原料,分别采用CuCl2、NiCl2、MnCl2、MgCl2、FeCl3、AlCl3、ZrOCl2、SnCl4为催化剂催化转化制备5-羟甲基糠醛(5-HMF)和乙酰丙酸(LA),筛选适用于琼脂糖转化的优选催化剂,并对制备条件如溶剂含水量、催化剂用量、反应温度以及反应时间等影响因素进行了考察。研究结果表明:以50 mg琼脂糖为原料,ZrOCl2为催化剂,二甲基亚砜(DMSO)为反应溶剂,在1 mL DMSO/H2 O(体积比为8∶2)混合溶剂中,ZrOCl2用量为琼脂糖中单糖物质的量的10%,140℃下反应60 min,5-羟甲基糠醛(5-HMF)的得率为26.9%,乙酰丙酸(LA)的得率为24.7%。对制备机理分析表明:反应过程中琼脂糖首先水解为醛型单糖,然后在催化剂作用下醛型单糖异构化再脱水转化为5-HMF,部分5-HMF在酸的作用下进一步转化为LA。 展开更多
关键词 琼脂糖 5-羟甲基糠醛 乙酰丙酸 ZrOCl2
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Catalytic transformations of cellulose and its derived carbohydrates into 5-hydroxymethylfurfural, levulinic acid, and lactic acid 被引量:12
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作者 Weiping Deng Qinghong Zhang Ye Wang 《Science China Chemistry》 SCIE EI CAS CSCD 2015年第1期29-46,共18页
The catalytic transformation of cellulose into key building-block or platform chemicals such as 5-hydoxymethylfurfural(HMF),levulinic acid,and lactic acid under mild conditions,has attracted much attention in recent y... The catalytic transformation of cellulose into key building-block or platform chemicals such as 5-hydoxymethylfurfural(HMF),levulinic acid,and lactic acid under mild conditions,has attracted much attention in recent years,as these conversions can be operated without consumption of hydrogen or oxygen and thus are more economical compared to the hydrogenolysis or oxidation of cellulose.This review article highlights recent advances in the development of novel catalysts or catalytic processes for the conversion of cellulose and its derived carbohydrates into HMF,levulinic acid,and lactic acid or their esters under inert atmosphere.We also analyze efficient catalytic systems for HMF production,in particular Lewis acids combined with ionic liquid or biphasic systems.For the formations of levulinic and lactic acids or their esters,we focus on the reactions in aqueous and alcohol media catalyzed by multifunctional catalysts that combine the functions of hydrolysis,isomerization,and dehydration-rehydration or retro-aldol reactions.The reaction mechanism for each process will also be discussed to gain insights into the activation of C–O and C–C bonds in the absence of hydrogen or oxygen. 展开更多
关键词 CELLULOSE multifunctional catalysis lactic acid 5-HYDROXYMETHYLFURFURAL levulinic acid
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5-氨基乙酰丙酸盐酸盐的工艺研究 被引量:1
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作者 刘东旭 王镜涵 胡志强 《山东化工》 CAS 2022年第1期68-70,83,共4页
5-氨基乙酰丙酸(5-ALA)盐酸盐作为一种环境相容性及选择性很高的新型光活化农药,在农业领域应用非常广泛。本文以乙酰丙酸为原料,经溴化、氨化和水解反应合成了5-氨基乙酰丙酸盐酸盐。该方法步骤简单、收率高、成本低、条件温和,具有良... 5-氨基乙酰丙酸(5-ALA)盐酸盐作为一种环境相容性及选择性很高的新型光活化农药,在农业领域应用非常广泛。本文以乙酰丙酸为原料,经溴化、氨化和水解反应合成了5-氨基乙酰丙酸盐酸盐。该方法步骤简单、收率高、成本低、条件温和,具有良好的市场前景。 展开更多
关键词 5-氨基乙酰丙酸盐酸盐 乙酰丙酸 溴化 水解
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Comparative study of microwave-assisted versus conventional heated reactions of biomass conversion into levulinic acid over hierarchical Mn_(3)O_(4)/ZSM-5 zeolite catalysts
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作者 Mazizah R.A.Helmi Dyah Utami C.Rahayu +3 位作者 Arnia P.Pratama Irena Khatrin Anita N.Ramadhani Yuni K.Krisnandi 《Carbon Resources Conversion》 EI 2023年第3期245-252,共8页
Conversion of delignified cellulose from rice husk biomass,and model compounds of cellobiose and glucose to levulinic acid(LA)over hierarchical Mn_(3)O_(4)/ZSM-5 catalyst was carried out using a household microwave me... Conversion of delignified cellulose from rice husk biomass,and model compounds of cellobiose and glucose to levulinic acid(LA)over hierarchical Mn_(3)O_(4)/ZSM-5 catalyst was carried out using a household microwave method,and then compared to the established conventional thermos-reaction method.The hierarchical ZSM-5 was prepared using a double template method,aiming for micro and mesoporous systems developed in the structure.The as-prepared ZSM-5 were modified with Mn3O4 through incipient wetness impregnation with Mn2+solution followed by calcination at 550℃.The catalysts were characterized using various techniques such as powder XRD,SEM,BET,AAS,and FT-IR which indicated the hierarchical structure of MFI zeolite(Si/Al of 30-34)with Mn loading of 2.14 wt%.The conversion products were analyzed using HPLC,1H NMR,and 13C NMR instruments.The microwave-assisted reaction using 600 W for 180 s using delignified cellulose,cellobiose,and glucose gave conversion of 37.27%,46.35%,and 54.29%,respectively which is close to the conversion given by the conventional reaction carried out at 130◦C for 4 h(36.75%,55.62%,and 60.9%,respectively).Interestingly,the LA yield from the microwave-assisted reaction(4.33%,6.12%,and 9.57%)is higher than the yield from the conventional reaction,which only produced 5.2%,4.88%,and 6.93%respectively.The microwaveassisted method is also shown to give less by-products compared to the thermochemical reaction.Therefore,it could be considered an alternative method for converting cellulose to LA. 展开更多
关键词 Hierarchical ZSM-5 zeolite levulinic acid Lignocellulose conversion Microwave-assisted synthesis CELLOBIOSE GLUCOSE
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Controlled drug release of 5-amino salicylic acid by poly(2- hydroxyethylmethacrylate) grafted agar
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作者 G. Usha RANI Kartick Prasad DEY Srijita BHARTI Sumit MISHRA 《Frontiers of Chemical Science and Engineering》 SCIE EI CAS CSCD 2014年第4期465-470,共6页
The utilization of poly (2-hydroxyethylmetha- crylate) grafted agar (Ag-g-P(HEMA)) as a matrix for the controlled release of 5-aminosalicylic acid was investi- gated. Grafted copolymers of 2-hydroxyethylmethacry... The utilization of poly (2-hydroxyethylmetha- crylate) grafted agar (Ag-g-P(HEMA)) as a matrix for the controlled release of 5-aminosalicylic acid was investi- gated. Grafted copolymers of 2-hydroxyethylmethacrylate (HEMA) monomers on agar were synthesized by micro- wave assisted method. In vitro drug release studies were performed at pH values of 2 and 7 in order to investigate the possibility of pH triggered release for colon targeted drug delivery. Further, the percent grafting vs. tso (the time taken for release of 50% of the enclosed drug) value was studied and the results indicate that it may be possible to develop a programmable drug release matrix based on grafted polysaccharide. Ag-g-P(HEMA) appears to be a useful matrix for controlled release. 展开更多
关键词 AGAR controlled drug release 5-amino sal-icylic acid poly(2-hydroxyethylmethacrylate) grafted agar
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高效液相色谱法对赤砂糖水解液中三种物质的分离和测定 被引量:5
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作者 刘柳 李果 +1 位作者 李利军 孔红星 《化学研究与应用》 CAS CSCD 北大核心 2012年第7期1036-1040,共5页
建立了一种同时分离、测定赤砂糖水解产物中的乙酰丙酸(LA)、5-羟甲基糠醛(5-HMF)和甲酸(FA)的高效液相色谱法。采用Agilent TC-C18色谱柱(4.6×250mm,5μm)、Agilent 1200 series VWD紫外检测器,以乙腈:磷酸-磷酸二氢钠缓冲溶液(pH... 建立了一种同时分离、测定赤砂糖水解产物中的乙酰丙酸(LA)、5-羟甲基糠醛(5-HMF)和甲酸(FA)的高效液相色谱法。采用Agilent TC-C18色谱柱(4.6×250mm,5μm)、Agilent 1200 series VWD紫外检测器,以乙腈:磷酸-磷酸二氢钠缓冲溶液(pH2.6)=15∶85(体积比)为流动相进行分离,检测波长210nm,柱温30℃,流速1mL/min。在此条件下,三种物质的色谱峰面积与浓度线性良好,线性相关系数r在0.9993~0.9999之间,平均回收率为99.02%~106.28%,精密度实验的相对标准偏差为0.25%~1.30%(n=5)。 展开更多
关键词 乙酰丙酸 5-羟甲基糠醛 甲酸 HPLC 紫外检测器
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