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氟氧化钕耐火材料的研制与应用 总被引:2,自引:0,他引:2
为给大型稀土金属电解槽提供一种抗氟盐侵蚀和高温抗氧化性好 ,且对稀土金属产品无污染的内衬材料 ,以氧化钕、氟化钕及钕电解槽炉底的结瘤物为主要原料 ,将氧化钕和氟化钕或炉底料按一定比例混合、压制成块和烧成来制备熟料 ,再将熟料破粉碎 ,配料成型 ,最后烧成 ,制备了以氟氧化钕为主要组成的新型耐火材料。通过实际应用表明 ,该材料具有一定的抗氟盐侵蚀能力和高温下的抗氧化能力 ,应用于大型稀土氟化物熔盐电解槽 ,可以保证槽体运行的稳定性和良好的经济技术指标 相似文献
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经过长期储存的Nd2O3能够吸收空气中的水分发生缓慢的反应生成氢氧化钕。通过TG和XRD分析证实样品中含有质量分数约66%的氢氧化钕,没有检测到碳酸钕或碱式碳酸钕。通过对不同温度下Nd2O3与水反应的结果考察,发现反应速度与温度有关,当温度超过30℃时,生成氢氧化钕的速度明显加快。通过焙烧的方式对已经变质的Nd2O3进行再生,发现当焙烧温度低于800℃时,有A型和C型2种晶型氧化钕,焙烧温度为800℃,只有A型氧化钕生成。上述结果表明Nd2O3在室温下与空气中的水反应并不迅速,而且很难吸收空气中的CO2。 相似文献
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三氧化二钕催化制备尼泊金乙酯 总被引:11,自引:0,他引:11
研究了以三氧化二钕为固体催化剂,由对羟基苯甲酸和乙醇合成尼泊金乙酯。讨论了影响酯化反应的因素,与大孔阳离子交换树脂和Fe2(SO4)3·XH2O相比,三氧化二钕用量少,是对酸的6%,反应时间短,只需4h,反应温度低,不超过90℃,可循环使用,产率较高,对环境和产品无污染等。 相似文献
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Preparation of mono-dispersed mixed metal oxide micro hollow spheres by homogeneous precipitation in a micro precipitator 总被引:1,自引:0,他引:1
For the preparation of mono-dispersed mixed metal oxide micro hollow spheres, homogeneous precipitation was carried out using a mixed metal sulfate precursor solution and an IPA (isopropyl alcohol) solvent in a micro precipitator configured with a micro capillary tip and a millimeter scale glass tube. The prepared micro particles revealed the morphology of hollow spheres with a narrow size distribution. For the preparation of uniform micro hollow particles without agglomeration the micro precipitator had to be operated in a laminar flow region with a low Reynolds number. The size of the particle could be controlled simply by changing the capillary tip diameter and/or the line velocity of the precursor solution and the IPA solvent. Also, the shell thickness of the hollow spheres could be controlled just by the concentration of the precursor solution. The mass production of micro hollow spheres by the micro fluidic device was validated in a micro precipitator inserted with multi-capillary tubes. 相似文献
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Synthesis and luminescent properties of Sr4−xSi3O8Cl4: xEu3+ red phosphor by hydrothermal method 下载免费PDF全文
Zhiren Wei Kun Zheng Tengxuan Hou Ruiqi Wang Zhe Wen Boyu Wang Xu Li Li Guan Zhiping Yang Feng Teng 《International Journal of Applied Ceramic Technology》2018,15(1):118-124
Sr4‐xSi3O8Cl4:xEu3+ (SSOC:Eu3+) phosphors were successfully synthesized by hydrothermal method. The crystallization of this phosphor was analyzed by means of X‐ray diffraction patterns. The size and morphology were recorded using SEM patterns of samples. And the PLE and PL spectra were characterized by a PL spectrophotometer. Excited by 394 nm UV light, the intense red emission is recognized in SSOC:Eu3+ phosphor and the main emission peak located at 620 nm. The influences of Eu3+ concentration, pH value of reaction solution, and charge compensator on PL spectra of SSOC:Eu3+ phosphors were investigated. The results revealed that this red phosphor had potential applications for white LEDs. 相似文献
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Fluorescence intensity ratios (FIRs) of the 640 nm and 602 nm emissions from Sm3+ were recorded at various temperatures T to identify the temperature increases ΔT associated with laser‐induced local heating of Ag nanoparticles. The FIRs increased as intensities of the excitation beam from a 532‐nm continuous‐wave laser increased. Estimated T of the irradiated region increased to as high as 586°C when at laser irradiation of 1.5 W on the surface containing Ag nanoparticles. Local heating due to the surface plasmon resonance of Ag nanoparticles is a main reason for the ΔT that eventually leads to precipitation of PbS quantum dots in glasses. 相似文献
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固液混合铸造Al-Cr合金的耐蚀性能研究 总被引:1,自引:0,他引:1
采用固液混合铸造新技术制备了Al-10Cr合金,通过对固液混合铸造Al-10Cr合金的阳极极化曲线测定,考察了其腐蚀性能。结果表明,当加粉量为40%、粉末粒度为74~175μm时可获得均匀的细晶组织,且耐腐蚀性能优于不加粉半固态铸造Al-10Cr合金。 相似文献
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Jiuxin Jiang Peiling Wang Wanbao He Weiwu Chen Hanrui Zhuang Yibing Cheng Dongsheng Yan 《Journal of the American Ceramic Society》2004,87(4):703-705
Self-propagating high-temperature synthesis (SHS) was applied to synthesize α-SiAlON powders doped by RE (RE = Eu,Pr,Ce) and codoped by RE and yttrium. The results showed that the weight ratio of α-SiAlON to (α-SiAlON +β-SiAlON) decreased from 70%, 55%, and 25% for europium-, praseodymium-, and cerium-doped α-SiAlON compositions, respectively, and the weight percentage of α-SiAlON phase increased to 100% for both (Eu,Y) and (Pr,Y) systems and 94% for the (Ce,Y) system, indicating SHS is a promising approach for synthesizing α-SiAlONs stabilized by the cations that could not be incorporated into the α-SiAlON structure by conventional sintering methods. 相似文献
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本文介绍了分光光度法测定双组分染料的原理,并通过测试铬黑T和茜素红混合染料对该方法进行了分析和验证。实验结果表明,该方法测定双组分混合染料中染料含量,方法简单,准确度高。 相似文献
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钠硼解石复合矿制取硼砂新工艺 总被引:1,自引:0,他引:1
针对青藏地区钠硼解石复合矿矿型特点,提出两步碱解法制取硼砂的新工艺。经正交试验考察碱用量、碱比例、液固比和反应时间等因素对反应浸出率的影响,确定的优化工艺条件为:n(Na2CO3):n(NaHCO3)=1:3,液固质量比为3,反应温度95℃,反应时间120min。试验结果:B2O3浸出率为98.89%,收率为93.68%,产品质量符合国家标准。该工艺收率高,耗碱量低,易于工业化。 相似文献