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Application of Nanopowder to High Temperature Single Crystal Fiber Sensor
Yanqi WANG,Xijun WULinhua YE,Limin TONG,Yonghang SHEN,

材料科学技术学报 , 1997,
Abstract: ZrO2, CuO, Al2O3 and SiO2 mixed nanopowder was used to coat the head of sapphire single crystal fiber for improving the properties of high-temperature single crystal fiber sensor. The result indicates that the head coated with above mixed nanopowder shows better optical stability,shorter response time and higher thermal shock resistance, in comparison with the head coated with coarse-grained particles with the same chemical compositions
STRUCTURE IMPROVEMENT AND TEMPERATURE FIELD SIMULATION OF PREPARING NANOPOWDER BY EVAPORATION-CONDENSATION METHOD

JSBao,YYin,TGLiu,ZYYang,

金属学报(英文版) , 2008,
Abstract: A new apparatus, with a segregable conical water cooling condenser, which is heated by an electric arc using the evaporation-condensation method to prepare carbon-coated nanopowder, has been developed by the authors. Numerical simulation of the temperaturc field is done by the ANSYS software, and temperature in the reaction vessel is measured with the help of an experiment, to verify the simulation result. Influence of the temperature field in the reaction vessel, on the process of preparing nanopowder is then discussed simply. It is shown that the segrcgable conical water cooling condenser and carbon-coated surface process can be used to prepare steady carbon-coated metal nanopowder, at a lower cost and higher yield rate than the traditional structure. Simulation of the temperature field in the apparatus shows that the arc heating method can form a temperature field in the apparatus, which is quite favorable for nanopowder formation. Experiments show that the rational parameters using this apparatus, with the arc heating method to prepare carbon-coated nanopowder are electricity 60-100 A and arc length 5-8 mm.
Investigation of The Effects of Reaction Temperature in NiFe2O4 Nanoparticles Synthesis by Hydrothermal Method  [cached]
Karc?o?lu Karaka? Z.,Boncuk?uo?lu R.,Ertu?rul M.,Karaka? ?.H.
Proceedings of the International Conference Nanomaterials : Applications and Properties , 2012,
Abstract: In this experimental study was investigated the effect of reaction temperature in NiFe2O4 nano particles synthesis with hydrothermal method. An appropriate ratio of solutions nickel nitrate and ferric nitrate were dissolved in deionized water and poured into a crucible. Later, polyethylene glycol 600 (PEG 600) was added to this mixture. Samples were adjusted to pH 11 values using NaOH solution . Accordingly, experments were made at 180, 200 and 250 oC, respectively. The other parameters, were fixed as reaction time 24 h and pH value 11. The structural and morphological properties of NiFe2O4 nano particles were determined by X-ray powder diffraction (XRD) and Scanning Electron microscopy (SEM). Results showed that increasing calcination temperature contributed to cyristallinity of NiFe2O4 nano particles. But also average particle size increased. As a result, average particle size was calculated by using Debye-Scherrer Formula as aproximately 30 nm. However, this results was confirmed with SEM andTEM analysis. Keyword: Nanoparticles, nickel ferrite, hydrothermal
The Effect of Calcination Temperature in NiFe2O4 Nanoparticles Synthesis with Microvawe Combustion Method  [cached]
Karc?o?lu Karaka? Z.,Boncuk?uo?lu R.,Karaka? ?.H.,Y?lmaz A.E.
Proceedings of the International Conference Nanomaterials : Applications and Properties , 2012,
Abstract: Magnetic ferrites are a group of technologically important magnetic materials. Synthesis of nanocrystalline spinel ferrite has been investigated intensively in recent years due to their potential applications in high-density magnetic recording, microwave devices, and magnetic fluids In this study, NiFe2O4 nano particles were prepared with microvawe combustion methods. In experiments, samples obtained by microvawe method were calcined at various temperatures. The structural and morphological properties of NiFe2O4 nano particles was determined by X-ray powder diffraction (XRD) and Scanning Electron microscopy (SEM). Results showed that increasing calcination temperature contributed to cyristallinity of NiFe2O4 nanoparticles. But also average particle size increased. As a result, average particle size calculated by using Debye-Scherrer Formula as aproximately 30 nm. However, this results was confirmed with SEM analysis. Keywords: Nanoparticles, nickel ferrite, microwave, calcination
Low-temperature synthesis of ZrO2-8 mol.% Y2O3 nanopowder with high sinterability  [PDF]
Karagedov G.R.,Avvakumov E.G.
Science of Sintering , 2011, DOI: 10.2298/sos1103239k
Abstract: The possibility of low-temperature synthesis of yttrium-stabilized (8 mol.%) zirconium dioxide nanopowder from a mixture of hydrated zirconium oxynitrate and yttrium carbonate mechanically activated in a continuous-type mill is examined. It is demonstrated that the powder formed at as low temperature as 600°C and then subjected to a disaggregation procedure can be easily compacted by dry pressing and achieves nearly full density on sintering.
扣锅煅藕节  [PDF]
彭云寿
中国中药杂志 , 1985,
Abstract: <正>据我院多年实践证明,扣锅煅藕节简单易行,成炭率高达98%,有效成分损失小,具体作法是:将净干藕节置一大铁锅中,装藕节量为锅容积的3/5为宜,上扣直径比底锅直径小1~2寸的铁锅一个,盖锅底部压一重物,两锅结合处用事先准备好的粘合剂(2/3黄土、1/3石灰、头发食盐少许加适量水混合而成)糊严,待粘合剂七、八成干时用武火煅制。判断煅藕节成功与否可用下列几种办法:1.往盖锅脐中滴水即沸,立即停火;2.在两锅合缝处留一筷子粗细的小
扣锅煅姜  [PDF]
徐永柏,王玉林
中国中药杂志 , 1983,
Abstract: <正>姜炭为常用中药,有温中止血之功效。据我们在五台县药材公司实践,扣锅煅姜简单易行,成炭率高,有效成分损失小。具体做法是:将干姜置一大铁锅中,上倒扣比底锅直径小1~2寸的铁锅,盖锅上压一重物,两锅合缝处用事先准备好的粘合剂(2/3黄土、1/3石灰、头发食盐各少许混合而成)糊严,待粘合剂7成干时用武火开始煅制,判断煅姜成功与否可用下列几种方法:1.往盖锅脐中滴水即沸,立即停火。2.在两锅合缝
煅制火候对贝壳类煅制品外观性状的影响  [PDF]
江文君,李铁林,李川,麻印莲
中国中药杂志 , 1995,
Abstract: 对4种贝壳类药材不同火候煅制品外观色泽、酥脆度及粉碎率进行了系统的考察和比较。煅制品外观性状的变化规律与煅制火候密切相关,煅制温度的影响大于煅制时间的影响。
低温固相反应法制备NiFe2O4纳米粉及机理研究  [PDF]
张志刚,刘宜汉,罗洪杰,姚广春
- , 2015, DOI: 10.12068/j.issn.1005-3026.2015.08.017
Abstract: 摘要 采用机械研磨方法制备前驱体,再将前驱体进行煅烧得到NiFe2O4纳米粉.重点研究了煅烧温度对粉体物相和形貌的影响以及固相反应过程与机理.结果表明:煅烧过程中晶粒长大活化能为12.08kJ·mol-1,主要以界面扩散为主;煅烧温度为700℃时粉体团聚严重,颗粒之间存在片状非晶态化合物,结晶度低;750℃煅烧1h得到的NiFe2O4纳米粉物相单一,粒径分布在35~85nm之间,温度过高时晶粒明显长大;机械研磨洗涤后前驱体主要由Fe2O3,NiO和NiFe2O4组成,反应产物结晶度低,反应不完全;盐颗粒的存在能抑制晶粒生长,减小产物粒径.
Abstract:The precursors ground by planetary ball milling at room temperature were calcined to obtain NiFe2O4 nanopowder. The effect of calcination temperature on the particle phase and morphology and the mechanisms of solid-state reaction were studied in detail. The results show that the activation energy of grain growth during calcination process is 12.08kJ·mol-1, indicating that the predominant mass transport mechanism is interfacial diffusion. The particles calcined at 700℃ showed strong agglomeration and low crystallinity with flaky amorphous compounds. The NiFe2O4 nanopowder calcined at 750℃ for 1h is of single phase with a particle size range of 35-85nm. The grains grew obviously when the calcination temperature increased to over 800℃. The main compositions of the precursor are Fe2O3, NiO and NiFe2O4. The low crystallinity of reaction products indicates the solid state reaction is not complete. The existence of salt particles can suppress grain growth, and thus decrease the particle size.
枯矾煅制经验  [PDF]
罗伟雄,黄入社
中国中药杂志 , 1990,
Abstract: <正>取口径约35cm的小生铁锅一口,白矾1公斤,置锅内以武火加热溶化,待煮沸2小时,散发大量水气,并开始凝固(但断续还有气泡鼓起冒出水气)时,改用中火煅1小时,至完全凝固无水泡鼓出后,改用文火,并将锅上加一铁盖,再煅约1小时,至全部松泡呈白色蜂
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