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纳米KNbO3粉体的水热合成及表征 总被引:2,自引:0,他引:2
给出了一个在Nb-K-H2O三元体系中水热合成KNbO3的新的工艺条件;讨论了水热反应温度、溶液初始浓度及反应时间对合成产物的组分及形态等的影响;采用水热合成方法,在KOH浓度3M以上、反应温度为250℃、反应时间24h时,成功合成了钙钛矿结构KNbO3纳米陶瓷粉体;X射线衍射(XRD)、透射扫描电子(TEM)分析表明,水热合成的KNbO3晶粒发育完整,平均粒径为40nm;FT-IR、FT-Raman光谱等测试结果表明,纳米尺度KNbO3晶粒的Nb-O特征振动吸收带和拉曼位移分别出现了宽化和蓝移现象. 相似文献
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对晶体电光调制实验中输出光波曲线特性的理论分析 总被引:1,自引:0,他引:1
根据铌酸锂晶体的电光特性,分析了电光振幅调制器的调制原理,讨论了直流偏压对输出光波特性的影响.结果表明,只有调制器工作在线性调制部分,才能实现电光调制激光通信. 相似文献
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The influence of direct quenching (DQ) on microstructure and mechanical properties of 0.19C-1.7Si-1.0 Mn-0.05Nb steel was studied. The microstructure and mechanical properties of reheat quenched and tempered (RQ&T) steel plate were compared with those of direct quenched and tempered (DQ&T) steel plates which were hot rolled at different finish rolling tem-peratures (1173 K and 1123 K), i.e., recrystallization-controlled-rolled direct-quenched (RCR&DQ) and controlled-rolled direct-quenched (CR&DQ), respectively. The strengths generally increased in the following order: RQ&T〈RCR&DQ&T〈 CR&DQ&T. Strength differences between the CR&DQ&T and RQ&T conditions as high as 14% were observed at the tempered temperature of 573 K. The optical microscopy of the CR&DQ&T steel showed deformed grains elongated along the rolling direction, while complete equiaxed grains were visible in RQ&T and RCR&DQ&T steels. Transmission electron microscopy (TEM) and electron backscattering diffraction (EBSD) of the DQ steels showed smaller block width and higher density of dislocations. Inheritance of austenite deformation substructure by the martensite and differences in martensite block width were ruled out as major causes for the strength differences between DQ and RQ steels. 相似文献
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<正>7月2日,中信铌钢优秀论文奖评审委员会在北京召开了中信铌钢优秀论文奖评审会议。为了更好地促进含铌钢新品种的开发及应用,中信微合金化技术中心对"中信铌钢优秀论文奖"的评审办法进行了改革,决定采用独立评审委员会进行评审的方式评奖,并将原自行申报制改为通过相关学术期刊发表的文章查询与筛选来确定入围论文。 相似文献
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采用锢-铌材料组件对超小型泵浦固体连续激光器的功率稳定性进行改良.通过采取平衡散热技术设计和铟-铌材料组件进行二次处理等方法试制样品并进行测试,分析试制前后铟材料的微观组织变化.结果表明,铟材料出现塑性变形,改良了激光器的局部热应力.铟-铌材料结构组件可有效提升超小型泵浦固体连续激光器输出激光功率稳定性,提高成品率. 相似文献
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