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1.
阴香种子油脂的提取及应用   总被引:2,自引:0,他引:2  
研究阴香种子油脂的提取工艺,从中分离并鉴定了其主要成分甘油三月桂酸酯.结果表明,阴香种子油脂的最佳提取条件为:以石油醚为溶剂.在50°C,料液比1:7,提取40 min,提取2次,总油脂的得率为64.2%,甘油三月桂酸酯的得率为40%.探讨了以阴香种子中甘油三月桂酸酯为原料合成甘油单月桂酸酯的方法.  相似文献   

2.
相转移催化合成蔗糖酯(Ⅳ)蔗糖月桂酸酯的合成   总被引:2,自引:0,他引:2  
研究了合成蔗糖月桂酸酯中采用相转移催化的基本原理和方法,考察反应时间,原料的不同配比和催化剂用量对蔗糖月桂酸酯产率的影响,得出反应时间为4.5h,原料配比为1∶1(摩尔数),催化剂用量为月桂酸甲酯摩尔数的8%时,其蔗糖月桂酸酯产率86.5%~91.2%,产物经纯化后测定,蔗糖单月桂酸酯按每克产品含蔗糖月桂酸单酯的摩尔数与理论计算的摩尔数之比为0.9725∶1.0000.  相似文献   

3.
水-醇为溶剂合成蔗糖月桂酸单酯的工艺研究   总被引:1,自引:0,他引:1  
以水-醇作为溶剂,在乳化条件下合成蔗糖月桂酸单酯.研究反应温度、时间、投料比的影响.在一定条件下,收率达到近80%.对反应中提高蔗糖月桂酸单酯的量及对薄层色谱分析用显色剂的条件进行了研究.  相似文献   

4.
以脂肪酶Lipozyme TLIM为催化剂在离子液体中选择性催化蔗糖和月桂酸乙烯酯合成了蔗糖月桂酸酯。利用单因素试验考察了酶制剂、离子液体种类、温度、原料的摩尔比、酶浓度对产率的影响,得到在离子液体[Bmim]BF4,反应最佳温度为45℃、糖酯最佳摩尔比为1∶4,最佳酶浓度为60 mg/mL。用TLC、HPLC、MS和NMR等手段对蔗糖-6-月桂酸单酯进行了表征。  相似文献   

5.
月桂酸聚乙二醇单酯的合成吴宝庆,果学军(化学系)关键词脂族酯;月桂酸;聚氧化乙烯;硼酸;合成;酯化;分解分类号:O623.624脂肪酸聚乙二醇酯是一种广泛使用于日用化工、纺织、合成纤维、农药等工业中的一种非离子型表面活性剂.它有较好的乳化性、润湿性、...  相似文献   

6.
为进行脂肪酸烷醇酰胺类表面活性剂研究,以月桂酸单异丙醇酰胺(LMIPA)为原料,通过羧甲基化法合成新型阴离子表面活性剂月桂酸单异丙醇酰胺羧酸盐(LMIPA-EC),对其合成条件进行探索,并测试其性能。结果表明:以80%氯乙酸溶液,固体NaOH的方式加料,配料比nLMIPA∶nClCH2COOH∶nNaOH=1∶1.5∶2.0,反应时间为3.5 h,反应温度为70℃左右较佳,在该实验条件下获得了81%的收率,经提纯后月桂酸单异丙醇酰胺羧酸盐的纯度可达92%;通过红外光谱对其结构进行了定性分析;同时测定了月桂酸单异丙醇酰胺羧酸盐的性能,测定结果表明:LMIPA-EC为性能比较优良的阴离子表面活性剂。  相似文献   

7.
文章以月桂酸,环氧氯丙烷为起始原料,四甲基乙二胺(TMED)为催化剂合成月桂酸丙(2-羟基-3-氯)酯.研究了反应时间、反应温度和催化剂用量对反应转化率的影响,确定合成目标产物的最佳反应条件为:甲苯作反应介质,催化剂用量为4%,900C下反应10 h,转化率为83.1%.终产物结构通过IR和1-HNMR分析得到证实.  相似文献   

8.
脂肪酸酰胺磺基琥珀酸单酯盐的合成与性能   总被引:1,自引:0,他引:1  
以月桂酸、乙醇胺、顺丁烯二酸酐、亚硫酸钠等为原料,经酰胺化、酯化、磺化三步反应合成了月桂酸酰胺磺基琥珀酸单酯钠盐阴离子表面活性剂。考察了各步反应的影响因素,确定了最佳合成条件;在催化剂存在下,控制反应温度分别为160_-170℃,70-80℃和100℃,制得活性物质含量为21%左右的目标化合物,并对其理化性质和表面活性进行了测定。  相似文献   

9.
绿原酸是一种天然酚类抗氧化剂,已应用于食品、医药、日用化工等行业中.然而,其易溶于水难溶于油的特性使其应用受到了限制.文中对绿原酸进行了改性,即在碱性催化剂催化的条件下使其与月桂酰氯进行非水相的酯化反应,得到了脂溶性的绿原酸月桂酸酯.经过单因素及正交试验,确定了最佳合成条件为:以N,N-二甲基甲酰胺作为溶解、稀释剂,绿原酸/月桂酰氯/三乙胺的摩尔比为1∶1∶1.5,温度控制在35℃,反应时间8 h.在此条件下,可得到微黄色粉状固体产物绿原酸月桂酸酯,其产率为81.24%.文中还通过UV-V is、IR、ESI-MS1、HNMR及元素分析法对产物的结构进行了表征,并采用量子化学计算论证了该分子修饰的可行性和合理性.  相似文献   

10.
以月桂酸甲酯与单乙醇胺反应制得了月桂酸单乙醇酰胺,再与P_2O_5反应合成了一种新型阴离子表面活性剂──烷基醇酰胺磷酸酯盐,初步探讨了该物质的合成条件,并测定了其物化性能。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

14.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

15.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

16.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

17.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

18.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

19.
Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of  相似文献   

20.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

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