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1.
以苯乙酮和2-羟基苯甲酰肼为原料,采用N,N-二苯基硫脲为催化剂,通过缩合反应合成新的酰腙化合物:苯乙酮-2-羟基苯甲酰腙.通过元素分析、红外光谱、热失重分析对其进行了表征.同时研究了催化剂用量与反应时间对酰腙收率的影响.结果表明,在回流条件下,催化剂N,N-二苯基硫脲用量为1.598 2g,反应6.0h时,酰腙收率可达到89.35%.  相似文献   

2.
研究了以2-壬酰氧基乙基氯甲酸酯和对羟基苯磺酸钠为原料,水为溶剂,氢氧化钠为缚酸剂,合成一种新型过氧化氢漂白活化剂4-(2-壬酰氧基乙氧基羰基氧基)苯磺酸钠的清洁工艺,考察了影响合成反应的主要因素。适宜的工艺条件为:n(2-壬酰氧基乙基氯甲酸酯)∶n(对羟基苯磺酸钠)∶n(氢氧化钠)=2.0∶1∶2.5,水为溶剂,反应温度60℃,反应时间4h,4-(2-壬酰氧基乙氧基羰基氧基)苯磺酸钠的收率高于67.0%。结果表明:该工艺具有操作简单、易控,环境友好等优点。  相似文献   

3.
杨宏黎 《中国油脂》2020,45(9):30-33
以三丁酸甘油酯和阿魏酸乙酯为原料,采用酶催化方法合成阿魏酰丁酸酯,通过单因素实验和正交实验研究溶剂体系、脂肪酶种类、溶剂配比、底物(三丁酸甘油酯与阿魏酸乙酯)摩尔比、反应温度、反应时间对阿魏酰丁酸酯转化率的影响,优化反应条件。结果表明:合成阿魏酰丁酸酯的最佳反应条件为脂肪酶Novozym 435为催化剂,酶添加量50 mg/m L,[EMIM][TF2N]-甲苯溶剂体系,[EMIM][TF2N]与甲苯质量体积比1∶1,反应温度50℃,底物摩尔比3∶1,反应时间6 d。在最佳反应条件下,阿魏酰丁酸酯转化率达76.24%。  相似文献   

4.
一步法合成H2O2漂白活化剂4-壬酰氧基苯磺酸钠的研究   总被引:1,自引:0,他引:1  
以4-羟基苯磺酸钠和壬酸为原料,亚硫酰氯为酰化剂,甲苯为溶剂,采用一步法合成了4-壬酰氧基苯磺酸钠.考察了影响合成反应的诸多因素.适宜的工艺条件为n(4-羟基苯磺酸钠)∶n(壬酸)∶n(亚硫酰氯)=1∶1∶1.3,反应温度为85℃,反应时间为5h,在此条件下,4-壬酰氧基苯磺酸钠的收率为84.5%,含量为95.8%,用红外光谱、核磁共振验证了目标产物.结果表明,该工艺具有操作简单、易控,产品质量好、收率高,溶剂易回收等优点.  相似文献   

5.
以2-氨基吡啶和氯乙酰氯为原料,合成2-(2-氯乙酰氨基)吡啶,进一步环合生成2-氧代-2,3-二氢-1H-咪唑并[1,2-a]-吡啶鎓氯化物.分别考察物质的量比、反应温度、反应时间对中间体及目标产物收率的影响.通过单因素试验,确定合成2-(2-氯乙酰氨基)吡啶的较佳工艺条件为:氯仿为溶剂,反应温度0℃,反应时间4 h,n(2-氨基吡啶)∶n(氯乙酰氯)=1∶1.5;合成2-氧代-2,3-二氢-1H-咪唑并[1,2-a]-吡啶鎓氯化物的较佳工艺条件为:乙腈为溶剂,反应温度75℃,反应时间12 h.利用1H-NMR和IR对中间体及目标产物结构进行了表征.  相似文献   

6.
以12-羟基硬脂酸和多亚乙基多胺为原料合成了聚12-羟基硬脂酸-多亚乙基多胺超分散剂,探讨了催化剂种类和用量、反应温度、反应时间对产品酸值的影响.聚12-羟基硬脂酸优化的合成工艺为:催化剂SnCl2.2H2O 0.6%,170℃反应18 h.在该工艺条件下,聚12-羟基硬脂酸的平均聚合度可达到8.接枝多亚乙基多胺的优化工艺为:160℃反应6 h.通过红外光谱分析可知产物即为聚12-羟基硬脂酸-多亚乙基多胺.  相似文献   

7.
由1-(5-溴-2-羟基苯基)乙酮和苯甲酰肼通过缩合反应,合成新的芳香酰腙化合物:1-(5-溴-2-羟基苯基)乙酮苯甲酰腙.通过X射线单晶衍射对该化合物进行晶体结构的表征.研究表明,该酰腙为单斜晶系,空间群为P2(1)/n,晶胞学数据a=0.737 61(15)nm,α=90°,b=2.827 0(6)nm,β=116.928(12)°,c=0.860 89(13)nm,γ=90°.V=1.600 5(5)nm3,Z=4,μ=2.570mm-1,Dc=1.383mg/m3,F(000)=672,R1=0.067 6[I2σ(I)],wR2=0.187 7.  相似文献   

8.
以2-氨基苯酚、丙酸为原料,多聚磷酸为催化剂,微波超声波辅助合成了2-乙基苯并噁唑.通过考察原料与催化剂摩尔配比,反应温度,反应时间等因素的影响,得出较佳工艺条件为:微波和超声波功率分别为800 W,2-氨基苯酚与丙酸的摩尔配比为1:5.5,催化剂多聚磷酸与2-氨基苯酚的摩尔配比为0.52:1,130℃,反应时间15 ...  相似文献   

9.
羟基酪醇是一种标志性多酚,其油溶性差且容易降解,将羟基酪醇修饰为油酸酯是提高其油溶性的有效途径。对羟基酪醇油酸酯的酶法合成进行了研究,考察了脂肪酶种类、酶添加量、醇酸摩尔比、溶剂(2-甲基-2-丁醇)用量、反应时间对合成反应的影响,并利用Box-Behnken中心组合的响应面设计优化了羟基酪醇油酸酯的合成反应条件。另外,采用质谱和核磁分析对产物进行了表征。结果表明:羟基酪醇油酸酯合成的最佳工艺条件为羟基酪醇500 mg、油酸2.474 g(醇酸摩尔比1∶2.7)、脂肪酶Novozym 435添加量2.2%(以整个反应体系的质量为基准)、溶剂用量2.6 mL、反应温度37℃和反应时间7 h,在此条件下羟基酪醇转化率高达89.6%;质谱和核磁分析证明成功合成了羟基酪醇油酸酯。脂肪酶催化合成羟基酪醇油酸酯的技术突破,可为延伸油橄榄产业链及副产物高值利用提供有力支撑。  相似文献   

10.
为改善现有9,10-二羟基硬脂酸合成存在的反应不连续、反应时间过长等问题,以油酸为原料,过氧化氢为氧化剂,在连续流反应器中合成9,10-二羟基硬脂酸,对催化剂进行了筛选,并对合成工艺条件进行单因素实验优化。结果表明,9,10-二羟基硬脂酸,合成的最佳工艺条件为以磷钨酸为催化剂、不使用溶剂、30%过氧化氢与油酸物质的量比3∶1、反应温度60℃、催化剂用量10%(以油酸质量计)、反应时间23.6 min,在此条件下油酸转化率为91.2%,9,10-二羟基硬脂酸选择性为82.6%。该方法解决了传统间歇釜式反应器中制备9,10-二羟基硬脂酸时反应时间长、工艺烦琐等问题,且绿色环保。  相似文献   

11.
Since grapevine ( Vitis spp .) rootstock material is being traded increasingly as disbudded woody material a lack of distinctive morphological features on such material necessitates an alternative and reliable means of identification. Methods described here were developed for rapid and efficient extraction of DNA from woody samples rich in phenolic compounds and polysaccharides, and for subsequent identification of varieties by RAPD PCR. Using these methods, and with the application of only one selected RAPD primer, we were able to differentiate sixteen rootstock varieties, including the seven varieties most commonly used in Germany. Problems commonly encountered with reproducibility of RAPD patterns were avoided by choosing primers with a dinucleotide sequence and a high G/C content that allowed a rather high annealing temperature of 45°C. Methods described here should also be useful for other horticultural crops, especially those with woody tissues rich in phenolic compounds and polysaccharides.  相似文献   

12.
An internet website (http://cpf.jrc.it/smt/) has been produced as a means of dissemination of methods of analysis and supporting spectroscopic information on monomers and additives used for food contact materials (principally packaging). The site which is aimed primarily at assisting food control laboratories in the European Union contains analytical information on monomers, starting substances and additives used in the manufacture of plastics materials. A searchable index is provided giving PM and CAS numbers for each of 255 substances. For each substance a data sheet gives regulatory information, chemical structures, physico-chemical information and background information on the use of the substance in particular plastics, and the food packaging applications. For monomers and starting substances (155 compounds) the infra-red and mass spectra are provided, and for additives (100 compounds); additionally proton NMR are available for about 50% of the entries. Where analytical methods have been developed for determining these substances as residual amounts in plastics or as trace amounts in food simulants these methods are also on the website. All information is provided in portable document file (PDF) format which means that high quality copies can be readily printed, using freely available Adobe Acrobat Reader software. The website will in future be maintained and up-dated by the European Commission's Joint Research Centre (JRC) as new substances are authorized for use by the European Commission (DG-ENTR formerly DGIII). Where analytical laboratories (food control or other) require reference substances these can be obtained free-ofcharge from a reference collection housed at the JRC and maintained in conjunction with this website compendium.  相似文献   

13.
The characterization of the aromatic profile of several apricot cultivars with molecular tracers in order to obtain objective data concerning the aromatic quality of this fruit was undertaken using headspace–solid phase microextraction (HS–SPME). Six apricot cultivars were selected according to their organoleptic characteristics: Iranien, Orangered, Goldrich, Hargrand, Rouge du Roussillon and A4025. The aromatic intensity of these varieties measured by HS–SPME–Olfactometry were defined and classified according to the presence and the intensity of grassy, fruity and apricot like notes. In the six varieties, 23 common volatile compounds were identified by HS–SPME–GC–MS. Finally, 10 compounds, ethyl acetate, hexyl acetate, limonene, β-cyclocitral, γ-decalactone, 6-methyl-5-hepten-2-one, linalool, β-ionone, menthone and (E)-hexen-2-al were recognized by HS–SPME–GC–O as responsible of the aromatic notes involved in apricot aroma and considered as molecular tracers of apricot aromatic quality which could be utilized to discriminate apricot varieties.  相似文献   

14.
The advent of the functional barrier concept in food packaging has brought with it a requirement for fast tests of permeation through potential barrier materials. In such tests it would be convenient for both foodstuffs and materials below the functional barrier (sub-barrier materials) to be represented by standard simulants. By means of inverse gas chromatography, liquid paraffin spiked with appropriate permeants was considered as a potential simulant of sub-barrier materials based on polypropylene (PP) or similar polyolefins. Experiments were performed to characterize the kinetics of the permeation of low molecular weight model permeants (octene, toluene and isopropanol) from liquid paraffin, through a surrogate potential functional barrier (25 μm-thick oriented PP) into the food simulants olive oil and 3% (w/v) acetic acid. These permeation results were interpreted in terms of three permeation kinetic models regarding the solubility of a particular model permeant in the post-barrier medium (i.e. the food simulant). The results obtained justify the development and evaluation of liquid sub-barrier simulants that would allow flexible yet rigorous testing of new laminated multilayer packaging materials.  相似文献   

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17.
This paper describes the second part of a project undertaken to develop certified mussel reference materials for paralytic shellfish poisoning toxins. In the first part two interlaboratory studies were undertaken to investigate the performance of the analytical methodology for several PSP toxins, in particular saxitoxin and decarbamoyl-saxitoxin in lyophilized mussels, and to set criteria for the acceptance of results to be applied during the certification exercise. Fifteen laboratories participated in this certification study and were asked to measure saxitoxin and decarbamoyl-saxitoxin in rehydrated lyophilized mussel material and in a saxitoxin-enriched mussel material. The participants were allowed to use a method of their choice but with an extraction procedure to be strictly followed. The study included extra experiments to verify the detection limits for both saxitoxin and decarbamoyl-saxitoxin. Most participants (13 of 15) were able to meet all the criteria set for the certification study. Results for saxitoxin.2HCl yielded a certified mass fraction of <0.07 mg/kg in the rehydrated lyophilized mussels. Results obtained for decarbamoyl-saxitoxin.2HCl yielded a certified mass fraction of 1.59+/-0.20 mg/kg. The results for saxitoxin.2HCl in enriched blank mussel yielded a certified mass fraction of 0.48 +/- 0.06 mg/kg. These certified reference materials for paralytic shellfish poisoning toxins in lyophilized mussel material are the first available for laboratories to test their method for accuracy and performance.  相似文献   

18.
<正>We are pleased to announce the launch of a new international peer-reviewed journal-Food Science and Human Wellness,ISSN 2213-4530,which is an open access journal,produced and hosted by Elsevier B.V.on behalf of Beijing Academy of Food Sciences.Food Science and Human Wellness is an international peer-reviewed English journal that provides a forum for the dissemination of the  相似文献   

19.
《印刷工业》2014,(11):95-95
According to Printing and Printing Equipment Industries Association of China(PEIAC)'s statistics to the plate manufucturer in China, in 2013, the actual offset plate production has reached 346 million square meters in China. Among them, the CTP production volume was 245 million square meters, up by 11% than that of last year; the total sales of the CTP plate was 239 million square meters, up by 13%.  相似文献   

20.
《印刷工业》2014,(8):103-103
正Held at Guangdong Modern International Exhibition Center,Print China 2015 will cover 7exhibition halls,besides the original Hall No.3,4,5,6,7,the newly built F zone of Hall 3 will be used too.The total area will be140,000 square meters.Hall 3:Offset and large printing equipment,package printing equipment,post press  相似文献   

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