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1.
以CTMAB为相转移催化剂,苯酐、正丁醇和苄氨为原料合成BBP的新方法。通过设计正交实验,对原料配比、反应时间、催化荆用量、pH值和加水量等影响因素以及催化荆的回收利用进行了研究。实验结果表明,苯酐:正丁醇:CT.MAB:苄氨为1:1.33:0.04:1.2,pH值为9,反应时间为3h,反应过程中的加水量为1%时最高酯产率可达到80%以上。本方法操作简单,耗时少,成本低,催化荆可回收利用,产品质量好,无“三废”污染,并易于工业化生产。  相似文献   

2.
阿司匹林的合成条件研究   总被引:7,自引:0,他引:7  
以水杨酸和醋酐为原料经O-酰化反应合成阿司匹林,比较了三氯化铝、三氯化铋和无水碳酸钠三种不同催化剂以及反应条件对合成的影响,找到了最佳催化剂和最佳反应务件,即以三氯化铝为催化剂,其用量为水杨酸的2%,水杨酸与醋酐的摩尔比为1:2,反应时间为30min,回流温度为85℃左右,阿司匹林产率可迭72.6%。实验表明该催化剂催化效果好.不污染环境,是一种环境友好的催化剂。同时,本法简单、快速、经济、无污染,产品质量好,适于工业化生产。  相似文献   

3.
利用钾长石粉水热合成13X沸石分子筛的实验研究   总被引:11,自引:0,他引:11  
对综合利用钾长石提钾工艺中的重要高附加值副产品13X沸石分子筛的合成进行了实验研究。对福建沙县的钾长石粉加入配料NaCO3进行焙烧实验,确定培烧的最佳工艺参数为:钾长石粉:NaCO3=1:1.30(摩尔比),焙烧温度为845℃,焙烧时间为150min;优化的水热合成条件为M2O/SiO2(mo1)=1.50,H2O/M2O(mo1)=40.0,合成时间为8h,晶种加入量为9.0%。对合成样品化学成分分析、X射线物相分析、红外光谱分析、扫描电镜分析表明,合成13X沸石分子筛结晶完好,性能优良.水热反应经由溶解水合反应和聚合浓缩反应两大阶段。  相似文献   

4.
基于0.02mol/L HCl介质中,痕量钴(Ⅱ)对重铬酸钾氧化偶氮胂Ⅲ褪色反应的催化作用,建立了测定痕量钴(Ⅱ)的动力学光度法。钴(Ⅱ)质量在0~4.0μg/L范围内服从比尔定律,方法检出限为0.076μg/L,在25mL溶液中,测定0.1μg钴(Ⅱ)的相对标准偏差为3.8%(n=11)。讨论了酸度、反应物浓度、温度、反应时间、干扰离子等因素的影响。研究了反应的最佳条件,并测定了一些动力学参数。催化反应的表观活化能为40.73kJ/mol。此法可用于井水、蜂蜜和维生素B12中钴(Ⅱ)的测定,相对标准偏差为1.8%-5.7%,标准加入回收率为99.6%~104.2%。  相似文献   

5.
以浓硫酸为催化剂,研究了对羟基苯甲酸和异丙醇合成对羟基苯甲酸异丙酯的工艺条件。对影响产率的因素进行了探讨:实验表明,在以7%的浓硫酸为催化剂,反应温度为120℃,醇酸摩尔比为4:1,反应时间为5h的最佳条件下,合成了羟基苯甲酸异丙脂,通过多次重结晶的方法纯化产品,产率可达85.5%,并通过熔点仪、红外光谱等手段对产品加以表征,验证了产品具有较高的纯度。该法简单、快速、产率高、纯度好,具有较高的实用价值。  相似文献   

6.
无水硫酸铜催化酯化反应性能的研究   总被引:1,自引:0,他引:1  
研究了无水硫酸铜为催化剂催化合成乙酸异戊酯的方法和条件,并在最佳条件下,以无水硫酸铜为催化剂催化合成了乙酸异戊酯、乙酸乙酯和乙酸丙酯等八种酯,比较了无水硫酸铜对低级脂肪酸的芳香酸酯化反应的催化效果。  相似文献   

7.
催化臭氧化降解有机废水及影响因素   总被引:2,自引:0,他引:2  
主要论述了自制的V-O型催化荆催化臭氧化降解有机废水的研究。试验表明,以TiO2,SiO2,ZrO2作栽体,在氮气或氧气中焙烧,而制得的6种催化荆中,V-O/SiO2/N2显示了较好的催化性能和活性;通过催化荆吸附试验和在反应体系中加入一定量的自由基猝灭荆,初步探讨了其催化机理,即催化荆和臭氧反应,生成了氧化性极强的羟基自由基;催化臭氧化时间、催化荆用量、进气臭氧浓度、体系pH值等因素均对降解产生一定的影响。  相似文献   

8.
药物中间体2-乙基苯并咪唑的合成   总被引:7,自引:0,他引:7  
报道了以邻苯二胺和丙酸为原料,磷酸催化合成药物中间体2-乙基苯并咪唑的研究。对反应条件进行了试验,结果表明,最佳的反应条件为:邻苯二胺与丙酸的摩尔比为1∶2.5,反应时间为2.0h,反应温度约为100℃,催化剂磷酸的用量为1.5mL,析出的游离2-乙基苯并咪唑的pH为9~10。合成的转化率高达78.09%。  相似文献   

9.
杂多酸(盐)催化合成水杨酸正丁酯的研究   总被引:3,自引:0,他引:3  
比较了多种杂多酸及其盐催化合成水杨酸正丁酯的反应,找到了该反应的最佳催化剂,并用正交试验法得出了反应的最优化条件,即醇酸摩尔比为2:1,催化剂用量为改质量的7%,反应时间为4h,酯产率可达87.7%。实验表明该催化剂催化活性高,选择性好,对设备无腐蚀,是一种环境友好的催化剂。  相似文献   

10.
杂多酸催化合成醋酸丁酯的研究   总被引:2,自引:1,他引:2  
本文研究了以磷钼杂多酸为催化剂,以无水氯化钙为吸水剂催化合成醋酸丁酯,并探讨了酸反应条件。结果表明,磷钼杂多酸具有较高的催化活性和选择性,在最佳条件下,酯产率可达96%,产品质量符合国标要求,该方法操作简便,条件容易控制,无污染。  相似文献   

11.
Pant-y-ffynnon Quarry in South Wales yielded a rich cache of fossils in the early 1950s, including articulated specimens of new species (the small sauropodomorph dinosaur Pantydraco caducus and the crocodylomorph Terrestrisuchus gracilis), but no substantial study of the wider fauna of the Pant-y-ffynnon fissure systems has been published. Here, our overview of existing specimens, a few described but mostly undescribed, as well as freshly processed material, provides a comprehensive picture of the Pant-y-ffynnon palaeo-island of the Late Triassic. This was an island with a relatively impoverished fauna dominated by small clevosaurs (rhynchocephalians), including a new species, Clevosaurus cambrica, described here from a partially articulated specimen and isolated bones. The new species has a dental morphology that is intermediate between the Late Triassic Clevosaurus hudsoni, from Cromhall Quarry to the east, and the younger C. convallis from Pant Quarry to the west, suggesting adaptive radiation of clevosaurs in the palaeo-archipelago. The larger reptiles on the palaeo-island do not exceed 1.5?m in length, including a small carnivorous crocodylomorph, Terrestrisuchus, and a possible example of insular dwarfism in the basal dinosaur Pantydraco.  相似文献   

12.
Robert L. Linnen   《Lithos》2005,80(1-4):267-280
The solubilities of columbite, tantalite, wolframite, rutile, zircon and hafnon were determined as a function of the water contents in peralkaline and subaluminous granite melts. All experiments were conducted at 1035 °C and 2 kbar and the water contents of the melts ranged from nominally dry to approximately 6 wt.% H2O. Accessory phase solubilities are not affected by the water content of the peralkaline melt. By contrast, solubilities are affected by the water content of the subaluminous melt, where the solubilities of all the accessory phases examined increase with the water content of the melt, up to 2 wt.% H2O. At higher water contents, solubilities are nearly constant. It can be concluded that water is not an important control of accessory phase solubility, although the water content will affect diffusivities of components in the melt, thus whether or not accessory phases will be present as restite material. The solubility behaviour in the subaluminous and peralkaline melts supports previous spectroscopic studies, which have observed differences in the coordination of high field strength elements in dry vs. wet subaluminous granitic glasses, but not for peralkaline granitic glasses. Lastly, the fact that wolframite solubility increases with increasing water content in the subaluminous melt suggests that tungsten dissolved as a hexavalent species.  相似文献   

13.
Calcite samples were extracted both from the rock matrix and the superficial coating of a karstified fault plane of an underground quarry, located in the eastern border of the Paris basin. The karstification is dated as Quaternary. Analysis of mechanical calcite twinning reveals that only the calcite matrix has also undergone a compression trending WNW that can be attributed to the Mio-Pliocene alpine collision. Both coating and matrix have undergone a strike-slip regime with σ1 roughly trending north–south, that could correspond to the regional present-day state of stress, a strike-slip compression rather trending NNW, modified by local phenomena. To cite this article: M. Rocher et al., C. R. Geoscience 335 (2003).  相似文献   

14.
HYDROGEOLOGY     
正20141756 Chen Ruige(Mathematical College,China University of Geosciences,Beijing100083,China);Zhou Xun Numerical Simulation of Groundwater Level Fluctuation in a Coastal Confined Aquifer with Sloping Initial Groundwater Level Induced by the Tide(Geological Bulletin of China,ISSN1671-2552,CN11-4648/P,32(7),2013,p.1099-1104,6 illus.,16 refs.) Key words:confined water,groundwater level  相似文献   

15.
正20141408 Cai Jia(Institute of Geology,Chinese Academy of Geological Sciences,Beijing100037,China);Liu Fulai Petrogenesis and Metamorphic P-T Conditions of Garnet-Spinel-Biotitebearing Paragneiss in Danangou Area,Daqingshan-Wulashan Metamorphic Complex Belt(Acta Petrologica Sinica,ISSN1000-0569,CN11-1922/P,29(7),  相似文献   

16.
17.
正20142386An Guoying(China Aero Geophysical Survey and Remote Sensing Center for Land and Resources,Beijing 100083,China)Application of Satellite Remote Sensing in Regional Hydrogeological Investigation:Taking Cenozoic Strata in Wenquan Sheet(1∶250 000)of Karakoram Range as an Example(Geosci-  相似文献   

18.
正20141016An Chengbang(Key Laboratory of Western China’s Environmental Systems,Ministry of Education,Lanzhou University,Lanzhou 730000,China);Zhao Yongtao Lake Records during the Last Glacial Maximum from Xinjiang,NW China and Their Climatic Impli-  相似文献   

19.
正20141538 Cao Qing(School of Earth Sciences and Engineering,Xi’an Petroleum University,Xi’an 710065,China);Zhao Jingzhou Characteristics and Significance of Fluid Inclusions from Majiagou Formation,Yichuan Huangling Area,Ordos Basin(Advances in Earth Science,ISSN1001-8166,CN62-1091/P,28(7),2013,p.819-828,7 illus.,3 tables,43 refs.)  相似文献   

20.
GEOCHEMISTRY     
正20142002 Wei Hualing(Institute of Geophysical and Geochemical Exploration,Chinese Academy of Geological Sciences,Langfang065000,China);Zhou Guohua Element Content and Mineral Compositions in Different Sizes of Soil in Tongling Area,Anhui Province(Geological Bulletin of China,ISSN1671-2552,CN11-4648/P,32(11),2013,p.1861  相似文献   

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