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纳米四氧化三铁的化学制备方法研究进展 总被引:1,自引:0,他引:1
阐述了纳米四氧化三铁在磁性材料、多功能材料、催化材料以及医学领域的应用现状。对纳米四氧化三铁的制备方法如沉淀法、溶胶-凝胶法、微乳液法、水热与溶剂热法、热分解法、静电纺丝法等做了介绍。分析了各种纳米四氧化三铁材料的形态如纳米颗粒、纳米棒、纳米线、纳米膜、杂化、核壳结构纳米晶等的适用领域。总结了各种制备方法的研究进展,分析了其优缺点并结合作者课题组在纳米四氧化三铁制备方面的研究工作,对纳米四氧化三铁的今后的研究方向作了展望:制备特殊形貌的纳米四氧化三铁材料、减少纳米四氧化三铁的团聚和氧化、多种制备方法的结合以及如何实现大规模工业化生产。 相似文献
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《无机盐工业》2017,(12)
铁化合物对水合肼还原硝基苯制备芳胺具有较高的活性,但重复性不好。以氯化铁和硫酸亚铁为原料采用共沉淀法制备了四氧化三铁,在制备过程中加入聚乙二醇(PEG)、十六烷基三甲基溴化铵(CTAB)和聚乙烯吡咯烷酮(PVP)3种表面活性剂对四氧化三铁进行改性。用X射线衍射仪(XRD)、透射电镜(TEM)和傅里叶变换红外光谱仪(FT-IR)对催化剂进行表征。结果表明,加入表面活性剂能够提高四氧化三铁粒子的分散性。以水合肼还原硝基苯为模型反应测试了加入表面活性剂前后制备的催化剂的活性,结果表明PVP改性的四氧化三铁具有较高的活性和较好的重复性,重复使用11次后其活性基本不变。催化剂具有磁性,便于回收。 相似文献
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以分析纯的硝酸铝和碳酸氢铵为主要原料,采用共沉淀法制备纳米氧化铝粉体,研究反应物的加料顺序和加料速度、表面活性剂种类、溶剂组成、晶种及前驱体的煅烧温度对产物的影响。采用X射线衍射仪分析粉体的物相组成,用谢乐公式计算晶粒尺寸,采用透射电子显微镜观测颗粒形貌。结果表明:原料的加料顺序对产物影响不明显,用PEG6000作表面活性剂,水和乙醇等体积混合液作溶剂,Al(NO3)3溶液直接倒入NH4HCO3溶液中制得前驱体,当煅烧温度为1135℃煅烧2 h时,制备了粒径为33 nm的α-Al2O3粉体,加入晶种后,煅烧温度可降低至1075℃。 相似文献
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采用微波法控制合成Silicalite-1纳米分子筛晶粒,研究微波时间对Sillcalite-1形成过程等微观性质的影响。通过调变晶化时间控制合成不同结晶度、粒径的Silicalite-1分子筛晶粒,为发展二次生长法合成分子筛膜的研究探索了一条合成晶种的新途径。结果表明,合成液经60℃恒温陈化24 h后,在相对温和的微波环境中(100℃)分子筛晶体形成缓慢,逐渐由无定形物质向Silicalite-1转变,相对结晶度随晶化时间延长而增大。微波150~240 min可合成粒径70~130 nm,相对结晶度82.4%~90.2%不等的Silicalite-1分子筛纳米晶粒,满足晶种法合成分子筛膜对不同晶种的需求。 相似文献
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试验研究硅烷偶联剂种类和用量以及复合材料制备方法对纳米四氧化三铁/NR复合材料物理性能的影响.结果表明,硅烷偶联剂可有效地对纳米四氧化三铁表面进行改性;透射电子显微镜、扫描电子显微镜和红外光谱分析结果表明,偶联剂Si69的改性效果较好,增强了纳米四氧化三铁/NR复合材料的界面作用,促进了纳米四氧化三铁粒子在NR中分散,改善了复合材料的结构和性能;当偶联剂Si69用量为2.25份时,纳米四氧化三铁/NR复合材料的综合物理性能最好.与机械共混法和磁流体-凝胶法相比,乳液共凝法制备纳米四氧化三铁/NR复合材料的物理性能较优. 相似文献
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乙烯酮(双乙烯酮)是十分重要的化工中间体,其下游产品较多。江苏某化工厂开发生产乙烯酮(双乙烯酮)下游产品三十多个,年生产规模三万多吨,是国内以乙烯酮(双乙烯酮)为中间体生产精细化学品的综合骨干企业。针对乙烯酮(双乙烯酮)下游产品废水特点,该厂结合企业实际,开展了产品优化,结构调整,清洁生产,资源循环利用,节水降耗等工作,从源头削减了污染物的生产。同时投资二千多万元新建预处理装置三套,6000m3/d废水生化处理装置一套,使全厂乙烯酮(双乙烯酮)下游产品的废水得到了有效的治理。 相似文献
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D. G. Gordeev L. F. Gudarenko M. V. Zhernokletov V. G. Kudel’kin M. A. Mochalov 《Combustion, Explosion, and Shock Waves》2008,44(2):177-189
A semi-empirical equation of state for metals is described. Its capabilities are demonstrated by the example of the equation
of state for aluminum. New experimental data are presented on the location of the isentrope of aluminum for unloading from
the state at p = 229.71 GPa on the shock adiabat to an aerogel (SiO2) of density 0.08 g/cm3.
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Translated from Fizika Goreniya i Vzryva, Vol. 44, No. 2, pp. 61–75, March–April, 2008. 相似文献
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Jorge Marcelo Romero Soledad Bustillo Hugo Enrique Ramirez Maisuls Nelly Lidia Jorge Manuel Eduardo Gómez Vara Eduardo Alberto Castro Alicia H. Jubert 《International journal of molecular sciences》2007,8(7):688-694
A thermochemical rather simple experimental technique is applied to determine the enthalpy of formation of Diperoxide of ciclohexanone. The study is complemented with suitable theoretical calculations at the semiempirical and ab initio levels. A particular satisfactory agreement between both ways is found for the ab initio calculation at the 6–311G basis This set level. Some possible extensions of the present procedure are pointed out. 相似文献
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A perturbation viscometer is a differential capillary viscometer that measures the logarithmic viscosity gradient of the viscosity-composition curve for gas mixtures. Measurements are made at different gas mixture compositions. Integration of the logarithmic viscosity gradients measured over the full composition range gives the mixture viscosity relative to the viscosity of one of the pure components of the gas mixture. This method is attractive because, for measurements of equal precision, integration of the gradients is potentially an order of magnitude more precise than measurement of the viscosities directly. It can also work at high and low temperatures and perhaps high pressures.The perturbation viscometer has been used to make measurements on ideal gas mixtures at ambient and elevated temperatures. The situation is more complicated when the gas mixtures are non-ideal. Extra effects due to density differences, molar volume change on mixing and differential thermal expansion may be measured in addition to the desired viscosity change producing systematic errors in the results. Thus, a more sophisticated apparatus is required. The standard perturbation viscometer has been modified to separate out the extra effects to permit measurement of the true change in viscosity. In addition, the theoretical operation of the modified apparatus has been revised to account for the design changes to permit calculation of the viscosity-composition profiles from the results.The apparatus has been tested using helium-HFC-125 mixtures and two new viscosity-composition profiles are presented for these mixtures at 23 and . Internal consistency tests have been used to confirm that the data produced are of high quality with an estimated uncertainty in the viscosity ratio data at of 0.9% and at of 1.5%. 相似文献
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塔设备改造选型的分析 总被引:2,自引:0,他引:2
就当前扩产增容中塔设备设计和改造时板式塔和填料塔的选型问题加以分析。在评述目前国内常用的几种塔板和新型填料之后,着重介绍一种新型塔板(导向梯形浮阀塔板)和一种新型填料(波环填料——乾隆帕克)。 相似文献