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以四氯化钛为原料,采用液相法制备出粒径约12nm,比表面积229.77m~2/g的纳米二氧化钛粉体。通过实验,用XRD,SEM对粒子的形貌、晶型、粒径进行了表征对比,并结合二氧化钛粉体制备的产率,对主要工艺参数进行了分析与讨论。 相似文献
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以工业钛液为原料,在常温常压下制备了锐钛矿型纳米二氧化钛粉体。用X射线衍射、高分辨率电镜、激光散射粒径分析、BET(Brunauer-Emmett-Teller)比表面积分析、X射线光电子能谱(X-ray photoelectron spectroscopy,XPS)和扫描电镜等对粉体进行了表征,研究了硝酸浓度和反应时间对粒径大小的影响。结果表明:制备的纳米二氧化钛呈球形,平均粒径小于10nm,粒径分布窄,结晶良好,BET比表面积为139.57m2/g。样品中的聚集体为近似球形,其尺寸为35nm。XPS分析表明:在纳米二氧化钛颗粒表面不仅包括钛、氧和碳元素,还包括氮、铁和硫元素。 相似文献
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以硫酸法钛白粉生产中间产物偏钛酸为原料,采用微乳法制备纳米二氧化钛粉体,研究表面活性剂加入量、沉淀剂加入量对颗粒粒径的影响,采用透射电镜(TEM)对颗粒的形貌进行表征,及X射线衍射仪(XRD)对制备颗粒的晶相成分进行分析。结果表明:制备的二氧化钛粉体晶型良好,粉体颗粒分布均匀,粒径为20-60nm。 相似文献
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二氧化钛超细粉末的制备新方法 总被引:1,自引:0,他引:1
随着纳米科技的迅速发展,纳米材料已经越来越多的应用于国民经济、军事及其它高新技术的各个方面。目前,在液相中制备纳米二氧化钛等纳米颗粒现阶段已经较为容易。但是,制备经过高温灼烧的超细粉体材料仍然存在着粉体粒度不够小,分散性能差、生产设备复杂,生产成本较高等诸多缺点。特别是随着粉体粒径的减小,其分散性能越来越差。如何制备出分散性能好、粒径小,生产工艺简单的超细粉体材料仍然是一个需要不断研究的课题。本试验采用液相凝胶法,以低成本的四氯化钛和氨气为原料,经过煅烧,制备了纳米级别的二氧化钛微粉材料。产品粒径10纳米左右,分散性能良好。 相似文献
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以硫酸氧钛为原料制备纳米二氧化钛 总被引:7,自引:0,他引:7
纳米二氧化钛是一种重要的新型无机功能材料,其制备及应用愈来愈受到重视。以硫酸法生产二氧化钛的中间产物——硫酸氧钛和偏钛酸为原料制备纳米二氧化钛粉体,具有原料来源广泛、价格低廉、有利于工业化生产等优点,是大规模制备纳米二氧化钛粉体的重要途径。重点对沉淀法、胶溶法、水热法制备纳米二氧化钛的工艺及特点进行了介绍,对工业化生产存在的问题及解决方法进行了讨论。 相似文献
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以钛酸四丁酯为主要原料,硫酸锰溶液为掺杂剂,采用超声分散法制备了含锰的二氧化钛光催化剂。并用X射线衍射(XRD)和透射电镜(TEM)对粉体的结构、粒径大小、物相、形貌等进行了表征。经500℃焙烧2h后,锰掺杂的二氧化钛粉末为锐钛型结构,其平均粒径为13nm,由于在XRD图谱上未发现有新相的生成,因此,可知锰离子是经过焙烧渗入到了二氧化钛的晶格中,掺杂所引起的变化主要是由于锰离子渗入二氧化钛晶格引起的。 相似文献
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A two-reverse-microemulsion precipitation technique was applied to synthesize nanocrystalline tetragonal zirconia using H2O solution/CTAB/hexanol as the microemulsion system. Two solutions of reverse microemulsion, one containing Zr4+ aqueous droplets and the other aqueous ammonia droplets with the same water/surfactant ratio, were prepared separately and mixed together to form a slurry of nanosized ZrO2 precursors, which filled the matrix of the surfactant, CTAB. The precursors were recovered, calcined to form nanocrystalline zirconia powder, and then characterized by using a transmission electron microscope to determine the particle size, a scanning electron microscope to examine the microstructure of the zirconia powder, and an X-ray diffractometer to determine the crystal phase and crystallite size. It is concluded that the primary particle size of the precursor determines the transformation temperature of the precursor and the crystal structure of the calcined zirconia. 相似文献
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A two-reverse-microemulsion precipitation technique was applied to synthesize nanocrystalline tetragonal zirconia using H2O solution/CTAB/hexanol as the microemulsion system. Two solutions of reverse microemulsion, one containing Zr4+ aqueous droplets and the other aqueous ammonia droplets with the same water/surfactant ratio, were prepared separately and mixed together to form a slurry of nanosized ZrO2 precursors, which filled the matrix of the surfactant, CTAB. The precursors were recovered, calcined to form nanocrystalline zirconia powder, and then characterized by using a transmission electron microscope to determine the particle size, a scanning electron microscope to examine the microstructure of the zirconia powder, and an X-ray diffractometer to determine the crystal phase and crystallite size. It is concluded that the primary particle size of the precursor determines the transformation temperature of the precursor and the crystal structure of the calcined zirconia. 相似文献
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纳米金红石型二氧化钛粉末的制备及表征 总被引:5,自引:0,他引:5
利用硫酸法制备钛白粉工艺的中间产物--钛液为原料,采用晶种制备-均匀沉淀法,成功制备纳米金红石型二氧化钛粒子.利用TEM,XRD,BET,ICP-AES等分析测试技术对粉体粒子的性能进行表征.结果表明,所得二氧化钛粒子为金红石型,形貌呈球形,平均粒径达80nm,产品纯度达99.95%,能满足市场需要. 相似文献
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Guotian Ye George Oprea Tom Troczynski 《Journal of the American Ceramic Society》2005,88(11):3241-3244
MgAl2 O4 spinel precursor was prepared by a novel method combining a sol–gel process with the "traditional" precipitation process. The thermal decomposition and phase development of the precursor were analyzed, and the degree of agglomeration of the calcined powder was assessed by determining its particle size and crystal size. The optimum calcination temperature was determined based on the variation of specific surface areas, crystal size, and particle size. Completely crystallized ultrafine spinel powder ( d 50 =600 nm, specific surface area=105 m2 /g) was obtained after calcination at 900°C. 相似文献
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The crystal habit of tamoxifen was modified using antisolvent crystallization techniques. Tamoxifen was crystallized from organic solvents using two different antisolvents (water and carbon dioxide). The habit of the precipitated crystals was modified by changing the process conditions, such as the solution and antisolvent mixing rate, the organic solvent, the presence of ultrasonic waves, and the addition of external additives. Particle size, crystal habit, particle aspect ratio and powder XRD patterns of the precipitated tamoxifen crystals were measured. With water as the antisolvent, the particle size of tamoxifen was significantly reduced compared to that of the raw material. When the antisolvent was carbon dioxide, the particle size was an order of magnitude greater than that of the raw material. The average aspect ratio of the tamoxifen crystals ranged from 1.8 to 16.2. The presence of ultrasonic waves caused a significant reduction in the aspect ratio, as well as the particle size. Furthermore, the addition of external additives was found to influence the crystal habit of tamoxifen. 相似文献
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以六水氯化镁为原料,氢氧化钠为沉淀剂,分别采用正向沉淀法、反向沉淀法、双向沉淀法和超重力沉淀法制备了纳米氢氧化镁,以沉降速度为评价指标,考察了制备方法对氢氧化镁料浆沉降性能的影响.利用透射电子显微镜(TEM)、纳米激光粒度分布仪、X射线衍射仪(XRD)对产物的形貌、粒径、粒径分布和晶型进行表征.结果表明,采用超重力沉淀法,氢氧化镁料浆的沉降速度明显加快,分别是正向沉淀法、反向沉淀法、双向沉淀法的4.7倍、12.4倍、2.1倍;所得氢氧化镁的分散性好,纯度高,粒度分布均匀并呈六方片状晶体. 相似文献