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介绍了3-烷基-2-2环戊烯-2-醇-1-酮的合成路线,操作条件,收率及产品物化性质。 相似文献
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本文以2-氨基-苯磺酸为原料,经重氮化,Sandmeyer溴化和氯磺化三步反应,得到2-溴-苯磺酰氯,对氯磺化过程进行改性,简化操作,提高了产物收率。 相似文献
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以w(NaOH)=33%水溶液为催化剂、乙醇胺、丁酮和二氯乙酰氯为原料,一步法合成了3-二氯乙酰基-2-甲基-2-乙基-1,3-恶唑烷。采用正交实验设计获得最佳反应条件;三氯甲烷做溶剂,反应温度-4-4℃,反应搅拌时间1h,产物收率78.6%。产品经红外光谱、核磁共振和元素分析确证。 相似文献
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以Al2O3, Fe2O3和Na2CO3为原料,对Na2O-Al2O3-Fe2O3系烧结过程中的反应行为进行了详细研究. 基于溶出率与时间、温度的关系,证明Na2O×Al2O3和Na2O×Fe2O3的生成反应动力学都服从Zhuralev-Lesokin-Tempelman模型,表观活化能分别为186.59和80.92 kJ/mol,表明Na2O×Fe2O3比Na2O×Al2O3在动力学上更易形成;Al2O3易与Na2O×Fe2O3反应形成Na2O×Al2O3和Fe2O3,在1273 K烧结30 min,所得熟料Al2O3溶出率达98.51%;Fe2O3对Na2O×Al2O3的形成有双重作用,在1273 K下可加速Na2O×Al2O3的形成,超过1323 K,促使Na2O×Al2O3分解成Na2O和b-Al2O3,且随着温度升高或时间延长,分解程度增高,从而导致熟料中Al2O3溶出率显著降低. 相似文献
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The coefficient of linear expansion, glass-transition temperature, temperature at the orset of deformation (strain point), density. Young modulus, microhardness, crystallizability, and contact angle are studied as a function of the composition in RO–Y2O3–Al2O3–SiO2 (R=Ca and/or Mg) glass systems. The composition ranges for glasses (with strain point >900°C and coefficient of linear expansion of (32–45)×10–7°C–1) that can be used for soldering silicon-nitride ceramics were established.Translated from Steklo i Keramika, No. 12, pp. 5–7, December, 1996 相似文献
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通过钕-铝系列色料合成实验,分析不同配比及不同矿化剂等对色料呈色效果的影响,确定最佳工艺方法。对实验结果进行XRD及色度分析,确定其主晶相为钕酸铝,试样的明度均在70以上,色彩鲜艳亮丽。 相似文献
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《Journal of the European Ceramic Society》2022,42(13):5820-5830
Cerium oxide doped with oxides of rare earth elements is a multifunctional material, a wide range of uses which is associated with its unique physicochemical properties. Phase diagrams of multicomponent systems are the physicochemical basis for the creation of new materials with improved characteristics.In this work, phase equilibria in ternary CeO2–La2O3–Dy2O3 and binary La2O3–Dy2O3 systems in the whole concentration range were studied. No new phases have been identified in these systems. An isothermal section of the phase diagram of the CeO2–La2O3–Dy2O3 system at a temperature of 1500 °С is constructed. No new phases have been detected in the system. It was found that in the studied ternary system solid solutions are formed on the basis of (F) modification of CeO2 with structure of fluorite type, monoclinic (B), cubic (C) and hexagonal (A) modifications of Ln2O3.In the La2O3–Dy2O3 binary system (1500–1100 °С) three types of solid solutions are formed: based on hexagonal modification A-La2O3, monoclinic modification B-Dy2O3 and cubic modification C-Dy2O3 separated by two-phase fields (A+B) and (B+C), respectively. The boundaries of the regions of homogeneity of solid solutions based on A-La2O3 are determined by compositions containing 35–40, 20–25, 15–20 mol% Dy2O3 at 1500, 1250, 1100 °C, respectively. From the obtained data it follows that the solubility of Dy2O3 in the hexagonal modification of lanthanum oxide is 39 mol% at 1500 °C, 23 mol. % at 1250 °C and 16 mol% at 1100 °C. The limits of existence of solid solutions based on monoclinic B-modification are determined by compositions containing 30–35, 65–60 (1250 °С), 35–40, 55–60 (1100 °С) 40–45, 70–75 (1500 °C) mol% Dy2O3.In the studied system, with a decrease in temperature from 1500° to 1100°C, there is a decrease in the solubility of La2O3 in the crystal lattice of cubic solid solutions of C-type from 16 to 10 mol%. 相似文献
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以w(NaOH) =33%水溶液为催化剂、乙醇胺、丁酮和二氯乙酰氯为原料 ,一步法合成了3 二氯乙酰基 2 甲基 2 乙基 1,3 口恶唑烷。采用正交实验设计获得最佳反应条件 :三氯甲烷做溶剂 ,反应温度 - 4~ 4℃ ,反应搅拌时间 1h ,产物收率 78 6 %。产品经红外光谱、核磁共振和元素分析确证。 相似文献
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以苯甲酰氯、四氯化碳、间甲基苯甲酰氰为原料,合成了标题化合物。重点考察了氰化过程中不同原料配比、反应温度、时间、溶剂和催化剂用量对收率的影响。实验结果表明,其最佳反应条件为:n(1,1,2-三氯-2-苯基乙烯)∶n(3-甲基苯甲酰氰)=1∶1.2,二氯甲烷为反应溶剂,3 mmol催化剂三乙胺,室温反应5 h,总收率达80.6%。 相似文献
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Bi_2O_3-B_2O_3-WO_3系统微晶玻璃的制备 总被引:1,自引:0,他引:1
采用熔融法制备了0.97[x Bi2O3(1-x)B2O3]·0.03WO3(0.25≤x≤O.75)基础玻璃,通过差热分析确定玻璃的特征温度,经热处理制备微晶玻璃.结果表明所制备的玻璃中只有x =0.67和x=0.60两个组成经热处理生成了微晶玻璃,颜色为乳黄色,晶相分别为BiO2和Bi2WO6,在扫描电镜下观察两种晶体的形貌均为颗粒状,晶粒尺寸在0.8~1.0μm.该体系玻璃的密度较大而硬度较小,但热处理后的微晶玻璃的密度和硬度均大于处理前的基础玻璃. 相似文献
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F. -T. Liou C. Y. Yang K. Hakim S. N. Levine 《Journal of Applied Electrochemistry》1983,13(3):377-382
Single crystal In2O3 shows promise as a photoanode for the decomposition of water. Because of various difficulties in the preparation of the single crystal material, two simple techniques were developed for the preparation of polycrystalline In2O3 anodes. One method involves the thermal decomposition of the nitrate while the other utilizes the chemical vapour deposition technique. Voltammograms and photoresponse spectra of these anodes are compared to the single crystal material. Among other observations, it is noted that the quantum efficiencies of the thermally decomposed films are comparable to the single crystal material. It is also shown that the on-set potential can be shifted to more negative values by forming the mixed oxide In2O3/Y2O3. 相似文献
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实验采用正交实验法和对比实验,通过对R2O-RO-AlO3-B2O3-SiO2系统的成釉机理分析及熔融特性、熔体的粘度和表面张力等性能的测试,探讨了该系统在骨质瓷中的应用。 相似文献