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1.
掺杂TiO2纳米粉的合成、表征及催化性能研究   总被引:40,自引:0,他引:40  
考察了制备方法对掺杂Fe  相似文献   

2.
张兰芹  展晓元  王杰  张智慧  徐国纲 《合成化学》2015,23(12):1166-1170
以球形石墨为原料, HClO4为插层剂,KClO3为氧化剂,采用高温(1 050 ℃)氧化还原法制备了石墨烯(GN),其结构和性能经FT-IR, XRD, SEM, TEM, BET和RS等表征。研究了KClO3的加入量对GN结构和性能的影响,结果表明:当KClO3的加入量为0.08 g·mL-1时,所制备的GN的比表面积为558 m2·g-1,平均孔径为3.012 nm,电阻率为0.02 Ω·cm。  相似文献   

3.
纳米纤维素的制备   总被引:22,自引:0,他引:22  
叶代勇 《化学进展》2007,19(10):1568-1575
在纳米尺寸范围操控纤维素分子及其超分子聚集体,结构设计并组装出稳定的多重花样,由此创制出具有优异功能的新纳米精细化工品、新纳米材料,是纤维素科学的前沿领域和热点。为了研究当前制备纳米纤维素的现状和发展方向,简述了纳米纤维素化学基础,介绍了三类纳米纤维素:纳米纤维素晶体(晶须)、纳米纤维素复合物和纳米纤维素纤维,重点综述了纳米纤维素的五种制备方法:化学法制备纳米纤维素晶体和晶须、生物法制备细菌纤维素、物理法制备微纤化纳米纤维素、人工合成纳米纤维素和静电纺丝制备纤维素纤维,讨论了各种制备方法的优点和缺点,指出开展纳米纤维素超分子的可控结构设计、立体与位向选择性控制与制备、分子识别与位点识别等自组装过程机理、多尺度结构效应的形成机理等基础理论性研究是主要研究基础,新型的、绿色、低能耗、快速、高效的制备方法是纳米纤维素制备方法的发展方向。  相似文献   

4.
An extremely simple method for preparing imines from aryl and alkylaryl ketones and a variety of amines is presented. The process involves the diffusion of the appropriate amine vapor from one arm of an H-tube into the other arm containing the ketone. Most reactions are quantitative, and, in many cases, there is no real work-up or purification required.  相似文献   

5.
羟基氧化铁;磁粉;复合添加剂在碱法制备α-FeOOH中的应用  相似文献   

6.
细小乳状液的制备   总被引:3,自引:0,他引:3  
For preparing O/W miniemulsions containing soybean oil and silicone oil, three methods, phase inversion emulsification, D-phase emulsification, reformed D-phase emulsification were tested by using Brij92, 97, 98 and Tween 80, 85, 60, 20 and Span 80, 60 mixed surfactants. It was found that the O/W miniemulsions of soybean oil and silicone oil can not be formed by phase inversion emulsification method, but can be formed by the two other methods. The results of emulsification showed that if gel emulsion, in which fine oil droplets disperse in continuous phase with high surfactant content, appears during the emulsification process, the O/W miniemulsions can be formed by simply diluting with water.  相似文献   

7.
Summary A series of gem-dinitroparaffins, from 1,1-dimtropropane to 1,1-dinitrodecane, were prepared by Chancel's reaction; their constants were measured, and the refraction of the dinitromethyl group was determined.  相似文献   

8.
Homolytic acylation of pyrazine and alkylpyrazines by aldehydes, as a source of an acyl radical, gives mainly monoacylation products. The reactions proceed in reasonable yields and provide a new route to pyrazine ketones.  相似文献   

9.
Aluminium hydroxide was prepared by precipitation from aluminium nitrate solution with ammonia solution. Thermal decomposition of the solid hydroxide was studied by means of TG, DTG and DTA. The sample was thermally treated in the temperature interval between 200 °C and 1000 °C. X-ray phase analysis was used to study the phase compositions of the resulting products, and their surface areas were compared.  相似文献   

10.
Monobromo-, monochloro- and monoiodopyrroles are obtained in excellent yields by using N-halosuccinimides in dimethylformamide as halogenating agents.  相似文献   

11.
朱延新  陈志勇  胡文浩 《合成化学》2004,12(5):427-428,434
在NaH存在下,3,3-二甲基丁酮和3,3-二甲基丁酸甲酯缩合制备了2,2,6,6-四甲基-3,5-庚二酮(1000g),收率66%,纯度可以达到98%(GC分析)。  相似文献   

12.
The poly-p-benzenesulfonamide (PBS) structure has been prepared by the transamidation of N1,N1-dimethylsufanilamide hydrochloride in a melt reaction at 180°C. The polymeric nature of the product is exhibited by brittle film formation and a glass transition temperature of 180–190°C. Infrared and NMR spectroscopy are consistent with the proposed structure. The number-average degree of polymerization was measured by NMR. The maximum degree of polymerization was 14. Failure to obtain an optimum molecular weight did not appear to be due to monomer purity. Increasing the reaction temperature from 180 to 220°C led to side reactions giving insoluble and infusible product. PBS underwent thermal decomposition near 310°C. The decomposition temperature is independent of molecular weight.  相似文献   

13.
A thorough investigation of the effect of reaction conditions on the direct formation of vinyllithium from vinyl chloride and lithium metal in tetrahydrofuran is reported. Under optimum conditions yields of 69 to 79% were dependably obtained.  相似文献   

14.
1,2-二苯乙烷的新合成法   总被引:8,自引:0,他引:8  
氯化苄;还原偶联;Cu2Cl2;1;2-二苯乙烷的新合成法  相似文献   

15.
作为一种新型的功能材料,导电水凝胶已经引起广泛的关注。本文根据目前的研究现状,将导电水凝胶大致分为聚电解质导电水凝胶,酸掺杂导电水凝胶,无机物添加导电水凝胶以及导电高分子基导电水凝胶等几大类,并综述了它们的制备方法。另外,由于大分子体系的导电高分子和水凝胶都有着独特和重要的性能,这使得它们具有广阔的应用价值。所以,本文在综述导电水凝胶制备进展的同时着重综述了导电高分子基导电水凝胶的制备进展。  相似文献   

16.
采用插层复合方法在碱性水溶液中制备了木质纤维素-蒙脱土纳米复合材料,并分析了反应温度、反应时间、木质纤维素与蒙脱土的质量比等因素对纳米复合材料有机化程度的影响,用FT-IR、XRD、TEM、SEM等方法对纳米复合材料的结构进行了表征。结果表明:蒙脱土片层结构在反应过程中被撑开,木质纤维素分散在其中,形成插层-剥离型纳米复合材料,其热稳定性较木质纤维素有了较大提高。  相似文献   

17.
通过淀粉纳米晶与苯乙烯乳液聚合的方法制备了聚苯乙烯接枝淀粉纳米晶并用FTIR和1HNMR进行了表征;制备了不同接枝聚苯乙烯单体与淀粉纳米晶的物质的量之比(MS)的聚苯乙烯接枝淀粉纳米晶,在苯乙烯单体和淀粉纳米晶摩尔比(M/SN)为2,反应时间为5~12h条件下,所得MS为0.15~0.67.X-射线衍射结果表明,接枝聚苯乙烯几乎不会改变淀粉纳米晶的晶型,但结晶度随着MS的增加而下降.  相似文献   

18.
棒状氢氧化镁的合成   总被引:3,自引:2,他引:1  
以氯化镁和氢氧化钠为原料合成了棒状氢氧化镁粉体。考察了氢氧化钠浓度、陈化温度、陈化时间对氢氧化镁形貌的影响。采用SEM、HRTEM、XRD、TG等对所得氢氧化镁颗粒的形貌、颗粒大小、晶习及热稳定性进行了表征。结果表明,当陈化温度为90℃时,所得棒状氢氧化镁随氢氧化钠浓度的升高及陈化时间的增加,晶形更加完整;当陈化温度在120℃时,所得氢氧化镁颗粒的形貌为片状,不能得到棒状氢氧化镁。  相似文献   

19.
通过Suzuki反应,由2-噻吩硼酸和相反应的卤代芳烃合成了2-芳基噻吩系列化合物,并用元素分析,IR、^1HNMR等对这些化合物进行了表征。  相似文献   

20.
对苯乙炔和吡啶乙炔类化合物的Heck反应进行了较全面的论述和仔细的研究,发现溶剂对催化体系有重要的影响。并成功的改进了一个Pd催化偶合反应。将该反应用于吡啶乙炔苯甲腈类化合物的合成。四个新的吡啶乙炔苯甲腈化合物被首次合成出来,从而为该类化合物的合成提供了一个有效而又方便的方法。  相似文献   

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