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1.
硅钨酸掺杂聚苯胺催化剂催化合成丁醛乙二醇缩醛   总被引:5,自引:1,他引:5  
自制了硅钨酸(H4SiW12O40)掺杂聚苯胺(PAn)催化剂H4SiW12O40/PAn。以丁醛和乙二醇为原料合成丁醛乙二醇缩醛,探讨了硅钨酸掺杂聚苯胺催化剂对缩醛反应的催化活性,较系统地研究了原料量比、催化剂用量、反应时间诸因素对产品收率的影响。实验表明:硅钨酸掺杂聚苯胺是合成丁醛乙二醇缩醛的良好催化剂,在n(乙二醇)/n(丁醛)=1 5,催化剂用量为反应物料总质量的1 2%,环己烷为带水剂,反应时间1 0h的优化条件下,丁醛乙二醇缩醛的收率可达89 7%。  相似文献   

2.
硅钨酸掺杂聚苯胺催化剂催化合成环己酮1,2-丙二醇缩酮   总被引:4,自引:0,他引:4  
采用回流法制备硅钨酸 (H4SiW12 O40 )掺杂聚苯胺 (PAn)催化剂H4SiW12 O40 /PAn。用环己酮和 1,2 丙二醇为原料合成环己酮 1,2 丙二醇缩酮 ,探讨了硅钨酸掺杂聚苯胺催化剂对缩醛反应的催化活性 ,较系统地研究了原料量比 ,催化剂用量 ,反应时间诸因素对产品收率的影响。实验表明 :硅钨酸掺杂聚苯胺是合成环己酮 1,2 丙二醇缩酮的良好催化剂 ,在n(环己酮 )∶n(1,2 丙二醇 ) =1∶14 ,催化剂用量为反应物料总质量的 1.6 % ,环己烷为带水剂 ,反应时间 5 0min的优化条件下 ,环己酮 1,2 丙二醇缩酮的收率可达 85 .6 %。  相似文献   

3.
硅钨酸掺杂聚苯胺催化剂催化合成环己酮乙二醇缩酮   总被引:9,自引:0,他引:9  
采用回流法制备了硅钨酸(H4SiW12O40)掺杂聚苯胺(PAn)催化剂H4SiW12O40/PAn。通过环己酮和乙二醇为原料合成环己酮乙二醇缩酮,探讨了硅钨酸掺杂聚苯胺催化剂对缩酮反应的催化活性,较系统地研究了原料量比、催化剂用量、反应时间诸因素对产品收率的影响。实验表明:在n(环己酮):n(乙二醇)=1:1.4,催化剂用量为反应物料总质量的0.8%,环己烷为带水剂,反应时间40min的优化条件下,环己酮乙二醇缩酮的收率可达91.2%。  相似文献   

4.
以硅钨钼酸(H4SiW6Mo6O40)掺杂聚苯胺(PAn)的H4SiW6Mo6O40/PAn为催化剂.对丁醛和乙二醇合成丁醛乙二醇缩醛进行了研究。考察了原料量比、催化剂用量、反应时间、带水剂用量等对丁醛乙二醇缩醛产品收率的影响。实验表明:硅钨钼酸掺杂聚苯胺是合成丁醛乙二醇缩醛的良好催化剂。在n(丁醛);n(乙二醇)为1:1.25,催化剂用量为反应物料总质量0.8%.环己烷为带水剂,反应时间1.0h的条件下,丁醛乙二醇缩醛产品收率为70.3%。  相似文献   

5.
以自制的磷钨酸(H3PW12O40)掺杂聚苯胺(PAn)H3PW12O40/PAn为催化剂,以丁醛和乙二醇为原料合成丁醛乙二醇缩醛,探讨了磷钨酸掺杂聚苯胺催化剂对缩醛反应的催化活性,用正交实验法研究了原料量比、催化剂用量、反应时间诸因素对产品收率的影响。实验表明:磷钨酸掺杂聚苯胺是合成丁醛乙二醇缩醛的良好催化剂,在n(丁醛):n(乙二醇)=1.0:1.1,催化剂用量为反应物料总质量的0.75%,环己烷为带水剂,反应时间1.0h的优化条件下,丁醛乙二醇缩醛的收率可达84.1%。  相似文献   

6.
自制了硅钨钼酸(H4SiW6Mo6O40)/PAn(聚苯胺)催化剂。通过丁醛和1,2-丙二醇为原料合成丁醛1,2-丙二醇缩醛,探讨了H4SiW6Mo6O40/PAn催化剂对缩醛反应的催化活性,较系统地研究了原料量比,催化剂用量,反应时间诸因素对产品收率的影响。实验表明:H4SiW6Mo6O40/PAn是合成丁醛1,2-丙二醇缩醛的良好催化剂,在n(丁醛):n(1,2.丙二醇)=1:1.7,催化剂用量为反应物料总质量的1.0%,环己烷为带水剂,反应时间40min的优化条件下,丁醛1,2-丙二醇缩醛的收率可达78.5%  相似文献   

7.
以硅钨酸(H4SiW12O40)掺杂聚苯胺(PAn)H4SiW12O40/PAn为催化剂,以乙酰乙酸乙酯和1,2-丙二为原料合成苹果酯-B,较系统地研究了原料摩尔比、催化剂用量、反应时间诸因素对产品收率的影响。实验表明:最佳反应条件为n(乙酰乙酸乙酯):n(1,2-丙二醇)=1:1.6,催化剂用量为反应物料总质量的0.75%,环己烷为带水剂,反应时间1.0h。上述条件下,苹果酯.B的收率为75.7%。  相似文献   

8.
硅钨酸掺杂聚苯胺催化剂催化合成丁酮乙二醇缩酮   总被引:7,自引:2,他引:5  
报道了以H4SiW12O40(硅钨酸)/PAn(聚苯胺)为催化剂,通过丁酮和乙二醇反应合成了丁酮乙二醇缩酮,探讨了H4SiW12O40/PAn对缩酮反应的催化活性,较系统地研究了酮醇物质的量比,催化剂用量,反应时间诸因素对产品收率的影响。实验表明:在n酮:n醇=1:1.5,催化剂用量为反应物料总质量的0.60%,环己烷为带水剂,反应时间2.0h的优化条件下,丁酮乙二醇缩酮的收率可达70.1%。  相似文献   

9.
杂多酸催化7-羟基-4-甲基香豆素的无溶剂合成   总被引:2,自引:0,他引:2  
秦省军  辛秀兰  徐宝财 《化学试剂》2007,29(10):614-616
报道了以杂多酸(H3PW12O40、H3PMo12O40、H8SiW12O42、H6P2W18O40、H4SiW12O40、H6PMo6W6O40)为催化剂,以乙酰乙酸乙酯和间苯二酚为原料,通过Pechmann反应合成标题化合物的方法。探讨了以H4SiW12O40为催化剂时反应温度、催化剂用量、反应时间、原料比诸因素对产品收率的影响。实验表明,H4SiW12O40是合成标题化合物的良好催化剂,在反应温度为130℃,反应时间为50min,n(间苯二酚)∶n(乙酰乙酸乙酯)=1∶1.3,催化剂用量为1.5%(与间苯二酚的物质的量比)时,产品收率75.9%。  相似文献   

10.
以正丁醛和1,2-丙二醇为原料合成了丁醛1,2-丙二醇缩醛,探讨了二氧化钛-二氧化硅负载硅钨酸催化剂对缩醛反应的催化活性。实验表明:H4SiW12O40/TiO2-SiO2是合成丁醛1,2-丙二醇缩醛的良好催化剂;在n(正丁醛)∶n(1,2-丙二醇)=1.0∶1.5,催化剂用量占反应物量总质量的1.6%,环己烷为带水剂6 m L,反应时间30 min的适宜条件下,丁醛1,2-丙二醇缩醛的收率可达88.8%。  相似文献   

11.
一年一届的中国国际塑料橡胶工业展览会(国际橡塑展),是全球多个行业寻找橡塑工业世界性商贸伙伴的机遇,也是企业开拓中国以至亚洲市场商机之"金钥匙"。在25届国  相似文献   

12.
Two series of semiinterpenetrating networks (SIPN) based on linear hydrophilic poly(vinyl alcohol) (PVA) and thermo‐responsive poly(N‐isopropylacrylamide) (PNIPA), physically crosslinked with inorganic clay, are presented. The hydrogels with different crosslinking densities were prepared by varying the content of clay from 1 to 6 wt % and contained linear interpenetrant, PVA in the range of 0.5–1.5 wt %. The effect of clay content on swelling/deswelling behavior and phase transition in PNIPA gels, as well as the feasibility of reinforcing the gels with high molecular weight PVA, were analyzed. The thermal response of hydrogels, followed by DSC, confirmed that the insertion of hydrophilic PVA did not have a significant effect on the onset of the volume phase transition temperature, while the response was faster. The equilibrium degree of swelling of SIPNs and PNIPA hydrogels was in the range of 9–79 and decreased with increasing content of clay. The internal morphology and surface wettability of the hydrogels were investigated by scanning electron microscope analysis and contact angle measurements, respectively. The network structural parameters of the PNIPA and SIPN nanocomposites hydrogels, such as the average molecular weight between crosslinks, Mc, and effective crosslinking density, Ne, were determined by dynamic mechanical analysis. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44535.  相似文献   

13.
Electrodialysis (ED) was applied to concentrate brine solutions of various concentrations — similar to effluentsfrom the desalination of brackish and industrial water — to about 20%. The consequent reduction in effluent volumes would facilitate a reduction in disposal costs. The energy requirement for concentrating solutions from 70 to 300 mN (0.4-1.8%) to 3.9 N (20%) was in the range 1.5-7.1 kWh/m3, in contrast to approximately 25 kWh/m3 by thermal evaporation. With the aim of preventing precipitation of CaSO4 on the membranes, laboratory-scale ED experiments were carried out on solutions of different compositions to determine the conditions that would lead to the precipitation of excess gypsum on gypsum seeds in a separate precipitator. The results were then applied in a pilot-scale ED unit in which the brine that circulated through the ED brine cells passed through a separate CaSO, precipitator containing gypsum seeds.  相似文献   

14.
Cyclopropenoids inactivated by reactingSterculia foetida oil with cottonseed oil fatty acids were fed at three dietary levels to growing rats and laying hens for 4 weeks. At the termination of the experiments, all animals were autopsied and examined microscopically for pathological lesions, but no pathology that could be related to dietary treatment was observed. Hemoglobin, packed cell volume and plasma cholesterol were similar in animals fed all of the diets. Growth rate of rats and egg production of hens fed the experimental diets were similar to those of animals fed the control diet. After 3 and 6 months of storage, eggs from hens fed the inactivated cyclopropenoids were normal and showed no evidence of the unusual characteristics of cyclopropenoid feeding. Lipids of heart, liver and adipose tissues of all the rats and hens varied little from the normal fatty acid composition. Small amounts of three unidentified fatty acids were found in the adipose tissues of rats fed the higher levels of inactivated cyclopropenoids. The results of these feeding studies suggest that inactivation of cyclopropenoids with fatty acids eliminates the unusual biological effects attributable to cyclopropenoids. Presented at the AOCS Meeting, New Orleans, April 1970.  相似文献   

15.
复合肥行业的转型升级已被列为化肥行业"十三五"规划重要内容。介绍我国复合肥行业转型发展期的特征,并提出在此形势下复合肥行业的发展思路;以创新谋发展,促进行业技术水平提高;以协作促转型,助推行业转型发展。  相似文献   

16.
目的探讨混合痔行PPH的护理方法。方法99例混合痔患者均行PPH,手术前向患者介绍住院环境、住院须知,告知治疗方法及护理上需要的配合,饮食、排便的注意事项,术前准备等;术后体位及恢复饮食时间,大小便情况观察及各种外用药的使用,出血护理及伤口护理,肛门功能锻炼;制定入院评估,印制出院指导。结果99例患者痔核明显回缩,顺利出院。结论混合痔PPH的术前术后护理对患者顺利康复有重要意义。  相似文献   

17.
Cotton fabric decorated with TiO2 synthesized by sol-gel approach was investigated as a self-cleaning material depending on the TiO2 loading (1.5 wt% in the case of single layered fabric and 3 wt% in the case of double layered). The materials were investigated by SEM, EDX, XRD, FTIR, and photoactivity. The self-cleaning property was established by determining the amount of the coated dust, the elemental composition, the carbon content, the opacity, and the water contact angle. The self-cleaning property of the impregnated fabric was accentuated by TiO2 loading. The dust deposited on the single layer fabric stored inside was 3.8 wt% lower than on the nonimpregnated fabric and that deposited on double layer fabric, respectively, was reduced by 9.1 wt%. The decrease in the deposited dust was more accentuated for the samples stored outside (4.2 wt% for the single layer fabric and 16 wt% for the double layer fabric, as compared with the nonimpregnated textile).  相似文献   

18.
山东铝业公司水泥厂(以下简称我厂)运行的大型高压电动机较多.有时由于长时间停运或者环境的潮湿,导致电动机的绝缘水平下降,致使电动机不能再次正常启动。因大型电动机是企业的关键设备,其运行好坏直接影响企业生产的正常与否,进而影响企业效益。  相似文献   

19.
OMC法煤气脱硫装置的操作经验   总被引:1,自引:0,他引:1  
讨论了在OMC法煤气脱硫工艺中,贫液碱度、贫液中盐类含量、脱硫剂OMC浓度和OMC质量等因素对煤气脱硫效率的影响,指出了提高脱硫效率的途径和降低消耗的经验。  相似文献   

20.
曹和胜 《轮胎工业》2006,26(9):564-565
介绍厦门正新橡胶工业有限公司在观念、产品、管理和技术方面开展创新活动的经验。观念创新是名牌战略的灵魂,相互理解与支持、创建伙伴关系是公司对外往来的原则,坚决实施名牌战略,坚持以人为本、适才适用的原则;产品创新是占领市场的法宝,根据市场需求不断适时开发新产品;管理创新是维护品牌形象的前提,各项试验均执行企业内控标准,严把产品质量关;技术创新是实施名牌战略的源泉,以自有技术开发各种轮胎。通过开展创新活动,公司利税指标一直位居国内前列。  相似文献   

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