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《广东化工》2021,48(6)
目的:调研市售驱蚊环和驱蚊贴的产品质量情况,参照相关标准方法对驱蚊环和驱蚊贴中的避蚊胺、驱蚊酯和派卡瑞丁进行检测,分析其存在的安全隐患;同时测试产品的驱蚊有效保护率,是否与外包装宣传一致。方法:检查了驱蚊环和驱蚊贴的包装标识和外观特征,用气相色谱法检测了避蚊胺、驱蚊酯、派卡瑞丁3种人工昆虫驱避剂含量。结果:发现20批次样品中大部分样品都称产品有效成分为天然植物精油成分且适用于婴幼儿或孕妇等特殊人群,1批次样品外包装显示含有人工合成驱避剂,90%样品的生产厂家均未进行农药登记。结论:驱蚊环和驱蚊贴产品存在标签标识混乱、配方安全性未得到验证、误导消费者等问题,有关监管部门和生产企业应重视这类新型驱蚊产品的质量安全。 相似文献
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正5合成5.1基本合成路线在AAS中,疏水基团可以连接在胺或羧酸部位,或通过氨基酸的侧链进行连接。以此为基础,有4种基本的合成路线可供选择[54],如图7所示。路径1:通过酯化反应生成两亲性酯胺(ester amine),在这种情况下,表面活性剂的合成通常是在脱水剂和酸性催化剂存在的情况下,通过回流脂肪醇和氨基酸来实现的。在某些反应中,硫酸同时起着催化剂和脱水剂的作用。 相似文献
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建立了测定10%驱蚊酯驱蚊液中甲醇杂质的气相色谱方法。采用气相色谱法,以去离子水为溶剂,使用30m×0.25mm×0.25μm INNOWAX毛细管柱和FID检测器,用气相色谱内标法对10%驱蚊酯驱蚊液中的甲醇进行分离和定量分析。结果表明,该分析方法的线性相关系数为0.9993,平均回收率为100.28%,标准偏差为0.000904,变异系数为0.7279%。 相似文献
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1-(4-氯苯基)-3-吡唑醇是合成吡唑醚菌酯的关键中间体,其合成及生产制约着我国吡唑醚菌酯的生产.综述了1-(4-氯苯基)-3-吡唑醇的合成路线,对各路线进行了评述,调研了目前产业化情况、下游吡唑醚菌酯生产及应用情况,并对1-(4-氯苯基)-3-吡唑醇开发应用前景进行了展望. 相似文献
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首先以二氢月桂烯和甲酸为原料、浓硫酸为催化剂,合成了甲酸1-(3,3-二甲基环己基)乙醇酯;然后甲酸1-(3,3-二甲基环己基)乙醇酯在氢氧化钠的甲醇溶液中皂化,得到了1-(3,3-二甲基环己基)乙醇;最后以对甲苯磺酸为催化剂,1-(3,3-二甲基环己基)乙醇与乙酸酐反应合成了玫瑰麝香酯。考察了原料摩尔比、反应时间和反应温度对玫瑰麝香酯产率的影响,并通过红外光谱、气-质联用和核磁共振等对所合成的中间体和目标产物的结构进行了表征,并对合成的玫瑰麝香酯进行了香气评价。结果表明,各步反应中均得到了目标产物;终产物玫瑰麝香酯的收率为91.1%,其具有温和的木香、玫瑰香、果香、甜香,并带有香叶、药草、麝香气息。 相似文献
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高吸油性树脂的合成和应用 总被引:19,自引:0,他引:19
本文叙述了高吸油性树脂的合成和应用方面的最新发展,介绍了六种现有的合成方法,简要说明其结构特点以及吸油特性。六种合成方法包括:单烯—双烯化学交联,溶剂致孔的单烯—双烯化学交联,官能团化学交联,辐射化学交联,聚氨酯泡沫,复合材料。高吸油性树脂的结构特点是:高分子之间形成一种三维的交联网状结构,材料内部具有一定微孔结构。由于树脂分子内的亲油基链段和油分子的溶剂化作用,高吸油性树脂发生膨润。吸油过程由分子扩散控制和Flory-Huggins方程控制两部分组成。适度交联,适当减小粒径可提高树脂的吸油速度。介绍了高吸油性树脂在三废处理、芳香剂、杀虫剂、诱鱼剂基材,纸张添加剂、渔网防污剂基材,合成树脂的改性添加剂等方面的应用 相似文献
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为了拓宽L-抗坏血酸酯在维护人体健康中的应用,将L-抗坏血酸转化成L-抗坏血酸酯是经济可行的手段。综述了近年来酶催化L-抗坏血酸有机酸酯的研究进展,重点介绍了有机相中L-抗坏血酸饱和脂肪酸酯、不饱和脂肪酸酯、脂肪酸混合酯的酶促合成,对于酶的种类、有机溶剂的选择及分离纯化方法进行了探讨,并对酶催化L-抗坏血酸有机酸酯合成前景进行了展望。 相似文献
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为研究非邻苯二甲酸酯类增塑剂在卷烟主流烟气的转移行为,将12种非邻苯酯类增塑剂添加到卷烟烟丝中,利用剑桥滤片捕集卷烟主流烟气,剑桥滤片和烟蒂分别经二氯甲烷萃取后,使用GC/MS/SIM分析各非邻苯酯类增塑剂在主流烟气的转移率和烟蒂的截留率。结果表明:12种非邻苯酯类增塑剂在主流烟气的转移率在7.86%~15.11%之间;12种非邻苯酯类增塑剂在烟蒂中的截留率在18.65%~36.54%之间;非邻苯酯类增塑剂在烟蒂中的截留率明显高于在主流烟气中的转移率,其中己二酸二乙酯在主流烟气中的转移率最低,而在烟蒂中截留率最高。 相似文献
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Eugene W. Blank 《Journal of the American Oil Chemists' Society》1962,39(2):122-123
Attention is directed to the variation in ester value of fatty acids depending upon method of isolation. The formation of
sterol esters increases the ester value of fatty acids. The increase of ester value with elapsed time is discussed. The effect
of ester value variation on the results obtained in soap analysis is described, and a possible basis of explanation for the
anomalous results frequently obtained with the Goldschmidt method is presented. 相似文献
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以L-氨基酸和醇为原料,酸性离子液体辅以少量强酸性阳离子交换树脂作催化剂,直接酯化合成了8种游离的L-氨基酸酯,并用1HNMR对产物进行了表征。通过L-苯丙氨酸正丁酯的合成对离子液体的活性进行了考察,结果表明,所选用的11种离子液体在反应过程中均起到了一定的催化作用和助溶作用。其中,[Hmim][HSO4]效果较好,在重复使用后,显示了较好的稳定性,是氨基酸酯化反应理想的催化剂和助溶剂。 相似文献
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Yurun Dai Heng Fang Zong Lu Zhuohong Yang Yanying Wei 《Frontiers of Chemical Science and Engineering》2022,16(11):1651
Two-dimensional nanosheets are highly effective tougheners for vinyl ester resins. The toughening effect is related to the high specific surface area and unique two-dimensional planar structure of the nanosheets. In this study, a coupling agent γ-(2,3-epoxypropoxy) propytrimethoxysilane (Kh-560) was used to modify MXene nanosheets (M-MXene) for use in toughening vinyl ester resin. The mechanical properties, including the tensile strength, flexural strength, Young’s modulus and elongation, of neat vinyl ester resin and vinyl ester resin modified with MXene and M-MXene were investigated. The results showed that modification significantly improved the mechanical properties of the vinyl ester resin. The tensile and flexural strengths of the MXene-nanosheet-modified vinyl ester resin were 27.20% and 25.32% higher, respectively, than those of the neat vinyl ester resin. The coupling agent improved the interfacial compatibility between the MXene nanosheets and vinyl ester resin, which resulted in the tensile and flexural strengths of the M-MXene-nanosheet-modified vinyl ester resin being 52.57% and 54.60% higher, respectively, than those of the neat vinyl ester resin for a loading quantity of nanosheets of only 0.04 wt %, which is economically viable. The main mechanisms by which the nanosheets toughen the resin are crack deflection and crack pinning. 相似文献
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Mass Spectrometric Fragmentation of Neopentylpolyolesters, Part IV: Fatty Acid Esters of Dipentaerythritol and Tripentaerythritol The fragmentation of some fatty acid esters of dipentaerythritol and tripentaerythritol upon electron impact ionisation was investigated. Main fragments in the spectra of dipentaerythritol ester arise by M-RCOO and cleavage of the ether bond. These ions are also formed in the spectra of tripentaerythritol ester by ether bond cleavage. Cyclic acetal structures for this ions are postulated. Their subsequent fragmentation, which was elucidated by DADI-measurements, leads to a striking similarity of the mass spectra of both ester types. Problems concerning the mass spectrometric identification of ester components formed by esterification of dipentaerythritol with mixtures of fatty acids is discussed. It is shown, that by GC-MS and calculation of the possible ester components using the known fatty acid composition, a detailed characterisation of these complex ester systems is possible. 相似文献
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Column chromatography on silver ion-saturated Amberlyst XN 1010 cation exchange resin gave very good separation of a mixture
of methyl 12-hydroxy-cis-andtrans-9-octadecenoates and of methylthreo-12, 13-dihydroxy-cis- andtrans-9-octadecenoates. Comparison of the retention volumes of nonhydroxy, monohydroxy, and dihydroxy saturated and monoenoic methyl
esters and of dienoic methyl esters shows that the hydroxy group interacts with the column packing to slow passage of the
compound through the column, although the effect of a hydroxy group is less than that of atrans double bond. The effects of the hydroxy groups are additive; the ratio of retention volumes of dihydroxy ester to monohydroxy
ester is slightly larger that that of monohydroxy ester to nonhydroxy ester. The retention volume of a cis monoenoic ester
is equal to that of a hydroxytrans monoenoic ester and that of a hydroxycis monoenoic ester is equal to that of a dihydroxytrans monoenoic ester. 相似文献