共查询到20条相似文献,搜索用时 64 毫秒
1.
改性吐温-20的合成及其乳化性能 总被引:1,自引:0,他引:1
利用羟基硅油的羟基与丁二酸酐反应,合成带有羧基的改性羟基硅油,其羧基与吐温-20分子中的羟基发生酯化反应,合成了含改性羟基硅油的改性吐温-20。乳化实验结果表明,羟基硅油改性吐温-20比吐温-20具有更好的乳化效果,离心分离稳定性更好。 相似文献
2.
介绍了FT合成烃类蜡的研究意义及从Schulz-Flory规律考虑高选择性合成蜡的可能性,重点介绍了Ru,Co,Fe等几种高选择性合成蜡的催化剂及其工艺条件,并对这几种催化剂进行了评述,参考文献29篇。 相似文献
3.
松香改性酚醛树脂的合成反应 总被引:7,自引:0,他引:7
研究了胶印油墨连接料用松香酚醛的合成反应,得出采用滴加酚醛浆的二步法合成工艺,可以有效地控制羟甲基酚经分子内脱水形成的次甲基酯。生成的苯并二氢吡喃型产物能显著地提高改性树脂的分子量和油溶性。 相似文献
4.
5.
6.
7.
8.
乳化分散法合成ZrO2纳米晶 总被引:8,自引:0,他引:8
本文以 Zr OCl2 · 8H2 O为主要原料 ,异丙醇作分散剂 ,用乳化分散法合成 Zr O2 并通过 TG— DTA、XRD、SEM和 TEM等测试手段对其进行了表征。得到了平均粒径小于 1 0 0 nm的纳米晶。 相似文献
9.
云南褐煤蜡氧化精制的研究 总被引:4,自引:1,他引:4
本工作对云南潦浒、寻甸、昭通蒙旦蜡进行了脱树脂,氧化精制研究,探索国产蒙旦蜡能否经精制后满足合成改性浅色蜡的要求。实验结果表明,潦浒、寻甸两厂生产的蒙旦蜡经氧化精制不能达到完全脱色,而昭通蒙旦蜡在相同的精制条件下极易脱色,所得浅色蜡质量达到和超过国外同类产品的水平,因此昭通蒙旦蜡是生产浅色蜡的理想原料。在精制反应中,加入适量YPSO-1添加剂,对改善反应条件,产物的分离,提高得率和质量均有良好的影响。文中还讨论了潦浒、寻甸脱脂蜡经氧化精制不能完全脱色的原因 相似文献
10.
稀土改性钛酸铅微粉的水热合成及其性能研究 总被引:4,自引:0,他引:4
用水热法合成了几种稀土(La,Pr,Nd,Sm,Eu)和锰掺杂改性的钛酸铅(PbTiO3,简称PT)陶瓷微粉,研究了掺La和Mn的PT固溶体的四方(铁电)相与立方(顺电)相之间的相变,掺杂La(x(La)=0.04)和Mn(y(Mn)=0.01)的PT固溶体的居里温度大约为400℃,测定了稀土掺杂量(x=0.04~0.08)与其压电性能之间的关系,随La掺杂量的增加,PT固溶体的d33增大,g33 相似文献
11.
12.
13.
《Analytical letters》2012,45(12):1057-1062
Abstract A method is described for the determination of microcrystalline wax in butadiene-styrene copolymer pellets at levels ranging from 0.10 to 0.55 wt. %. Polymer pellets are contacted with hot isooctane. The mixture is cooled and the solvent decanted. Following further cooling, the turbidity of the extracted solution is measured. The amouit of microcrystalline wax is calculated using a calibration curve derived from prepared standards. The limit of detection is 0.1% microcrystalline wax, due to sample background turbidity. 相似文献
14.
15.
Wax treatment of wood slows photodegradation 总被引:2,自引:0,他引:2
Boštjan LesarMatja? Pavli? Marko Petri?Andrijana Sever Škapin Miha Humar 《Polymer Degradation and Stability》2011,96(7):1271-1278
Waxes and wax emulsions are one of the most important solutions for non-biocidal wood protection. Wax treated wood is designed for outdoor use, therefore it is of considerable importance to elucidate the influence of weathering on the photodegradation processes. It is presumed, that wax treatment will reduce water uptake and thus reduce or slow down photodegradation processes. In order to test this hypothesis, three types of wax emulsions at two different concentrations were vacuum impregnated into Norway spruce wood specimens: an emulsion of montan wax (LGE), an emulsion of polyethylene (WE1) and an emulsion of oxidized polyethylene (WE6) wax. The samples were exposed to artificial accelerated weathering (AAW) for 500 cycles. Before and after AAW colour, the contact angle of water and moisture content were determined. Chemical and morphological changes at exposed surfaces were also investigated with FTIR spectroscopy and SEM. In parallel, the uptake of wax emulsions and water into the axial surfaces of samples was determined with a tensiometer. The moisture content measurements showed that the best hydrophobic effect was achieved with LGE treated wood, where the lowest colour and FTIR changes were observed as well. These results were supported by tensiometer measurements as well. Presented data clearly showed that high loadings of waxes reduce or at least slow down weathering. Among tested waxes, montan wax was found the most effective. 相似文献
16.
本文在非水溶剂中用液相还原法制备出DDP修饰的铜超微粒子,对制备条件作了初步探讨.Cu-DDP超微粒子的表征结果表明其粒径小、分布均匀,且在有机溶剂中有较好的分散性,显示出良好的润滑应用前景。 相似文献
17.
18.
卟啉在纯铁表面上的化学与电化学修饰 总被引:1,自引:0,他引:1
通过在卟啉的丙酮-水溶液中循环阳极电位扫描,在工业纯铁表面形成一层修饰层.此修饰层呈淡黄色,结晶细密.与基体结合牢固,耐腐蚀性能良好.质谱分析及反射红外分析说明有铁卟啉螯合物生成.若将工业纯铁直接浸入卟啉的丙酮-水溶液中,其表面同样也可形成一层修饰膜, 此膜较之电化学修饰层疏松而厚.卟啉在纯铁表面的电化学修饰层与化学修饰膜的形成机制有着本质的不同. 相似文献
19.
M. A. Rodríguez‐Valverde R. Tejera‐García M. A. Cabrerizo‐Vílchez J. Nolla‐Anguera J. Esquena‐Moret 《Journal of Dispersion Science and Technology》2013,34(2):155-163
In this study, effect and correlation of alkyl chain length (C8, C10, C12, C14, and C16) and concentration of n-alkyl sulfate acid used as representative Br?nsted acid-combined-surfactant catalysts on dehydration esterification of oleic acid with 1-octanol as typical substrates are researched. CMC of the series surfactant are measured by surface tension method. The results indicate that alkyl chain length as well as concentration of catalyst plays an important role in determining conversion of esterifications. Appropriate chain length surfactant and concentration should be chosen for the combined-surfactant catalyzed reaction. 相似文献
20.
建立了超高效液相色谱-串联质谱法同时检测莲雾中氟硅唑、戊唑醇、抑霉唑和烯唑醇4种杀菌剂的分析方法。莲雾样品经改进的QuEChERS方法进行前处理,超高效液相色谱-串联质谱法(UPLC-MS/MS)测定。氟硅唑、戊唑醇、抑霉唑和烯唑醇的质量浓度在5.0~500.0ng/mL范围内线性良好,相关系数均大于0.99;检出限在0.30~0.80μg/kg之间;平均加标回收率在79.2%~122%之间;相对标准偏差(RSD)在1.4%~9.6%之间。该方法简便、快速、准确度高,可用于莲雾中氟硅唑等四种杀菌剂的检测。 相似文献