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61.
Through measuring the alkali resistance of the invert glass and the quanity of SiO2 and TiO2 migrating fron the glass into the solution, the influence of TiO2 on the alkali resistance of the glass is discussed and its structure is also analyzed by infrared spectroscopy. It is concluded
that TiO2 has double functions for the alkali resistance of the invert glass. On the one hand, both TiO2 polarizing the secondary ions in glass and TiO2 isomorphism replacement of SiO2 make the alkali resitance of the glass decrease. On the ther hand, TiO2 patching network and anti-erosion covering help to increase the alkali resistance.
ZHAO Qing-lin: Born in 1972
Funded by the National Natural Science Foundation of China(No. 59372081) 相似文献
62.
甲基红掺杂液晶E7的光限幅特性研究 总被引:2,自引:0,他引:2
研究了甲基红染料掺杂的液晶混合物E7对波长为 5 32nm的纳秒脉冲激光的光限幅特性 ,观察了激光通过液晶盒后的远场光强分布及其随入射光能量的变化。实验发现 ,对于厚度为 4 6 μm ,重量体积比为 6mg/ 0 5ml的甲基红染料掺杂的液晶混合物E7薄膜 ,其最初三次测试的箝位输出值分别为 0 70 μJ,1.0 0 μJ和 1 5 2 μJ ,输入限幅阈值在 2 3~ 2 8μJ之间。这种薄膜的极低箝位输出特性对用于人眼和传感器保护的光限幅应用很有意义 相似文献
63.
锂离子电池正极材料Li1+xV3O8的研究进展 总被引:1,自引:0,他引:1
层状结构材料Li1 xV3O8有可能成为新一代锂离子电池正极材料。综述了锂离子电池正极材料的结构特点,重点介绍了国内外Li1 xV3O8的几种合成方法,分析了Li1 xV3O8的掺杂改性研究,总结了正极材料Li1 xV3O8的充放电工作原理,并展望了锂离子电池正极材料Li1 xV3O8未来应用前景。 相似文献
64.
掺锆纳米TiO2制备表征及其对光催化活性的影响 总被引:7,自引:0,他引:7
本文采用溶胶-凝胶法制备纳米二氧化钛和掺锆二氧化钛粉末.TGA表征分析发现掺锆后二氧化钛吸附水量增加.SEM和BET表征显示掺锆粒子半径减小,比表面积增加.XRD分析发现掺锆后的衍射峰宽化,晶粒变小,与SEM和BET结果吻合,还发现掺锆抑制了二氧化钛晶相转变.光催化降解亚甲基蓝结果表明,当锆掺杂浓度在5%,焙烧温度530℃时,掺锆二氧化钛催化活性最高. 相似文献
65.
Yu Hua Wang Tadashi Endo Xuan Guo Yukio Murakami Mizumoto Ushirozawa 《Journal of the Society for Information Display》2004,12(4):495-499
Abstract— The broad bands at around 155 nm for GdAl3(BO3)4:Eu, at 184 nm for Ca4GdO(BO3)3:Eu, at 183 nm for Gd2SiO5:Eu, and at 170 nm for GdAlO3:Eu were observed. These bands were assigned to the charge‐transfer (CT) transition of Gd3+‐O2?. In the excitation spectrum of (Gd,Y)BO3:Eu, a broadened excitation band was observed in VUV region. It could be considered that this band was composed of two bands at about 160 and 166 nm. The preceding band was assigned to the BO3 group absorption. The later one at about 166 nm could be assigned to the CT transition of Gd3+‐O2?, according to the result of GdAl3(BO3)4:Eu, Ca4GdO(BO3)3:Eu, Gd2SiO5:Eu, and GdAlO3:Eu. The excitation spectra overlapped between the CT transition of Gd3+‐O2? and BO3 groups absorption. It caused the emission of Eu3+ to take place effectively in the trivalent europium‐doped (Gd,Y)BO3 host lattice under 147‐nm excitation. 相似文献
66.
Jianjun Yang Ting WangDongchuan Chen Guodong ChenQuanlin Liu 《Materials Science and Engineering: B》2012,177(18):1596-1604
We have synthesized CaAlSiN3:Eu phosphors through an alloy-nitridation method with stable alloys as main starting materials, and investigated their crystal structures and photoluminescence properties in three aspects as below: (1) different Eu concentrations; (2) different Eu dopants; (3) different Al/Si molar ratios. The lattice volume calculated by using Rietveld refinement on the base of XRD analysis, decreases with oxygen incorporating, increases with the Al/Si ratios, and shows a limited expansion with the raise of Eu concentrations in CaAlSiN3:Eu crystal lattice. The concentration quenching and the shifts of emission bands are investigated and discussed in details. The different lattice volumes deriving from corresponding compositions have an important effect on photoluminescence properties. This work provides some methods to tune the emission wavelengths of CaAlSiN3:Eu phosphors. 相似文献
67.
68.
Farshid Nouri-Ahangarani Mehdi Nekoomanesh-Haghighi Milad Karbalaie 《Designed Monomers and Polymers》2016,19(5):394-405
In this article, polymerization of 1-hexene with FeCl3-doped Mg(OET)2/TiCl4/electron donor (ED) catalytic system is presented. For this purpose, first a number of TiCl4 catalysts supported on Mg(OEt)2 and Fe-doped Mg(OEt)2 supports were prepared with ethylbenzoate or dibutylphthalate as the internal EDs. After successive catalysts synthesis, they were employed in 1-hexene polymerization using cyclohexyl methyl dimethoxysilane as external ED as well as without it. The catalysts activity and molecular weight distribution (MWD) of poly 1-hexenes (PHs) were influenced strongly by both FeCl3 doping and donor presence so that a remarkable increase in the catalyst activity was seen in doped catalysts. Deconvolution of MWD curves revealed that increase in the type of active centers by introducing FeCl3 into the support should be responsible for the broadening of MWD of PHs. 13CNMR analysis indicated that while isotacticity does not change considerably by Fe doping, EDs increase its amount as high as 8–21%. Second, the stereoselective behavior of active Ti species in doped and undoped catalysts was fully explored by molecular modeling using density functional theory (DFT) method. Finally, with the aid of rheological measurements, the processability of polymers were evaluated and then the gel permeation chromatography (GPC) results were approved through the values obtained from model fitting as well as changes in moduli crossover modulus. 相似文献
69.
《Ceramics International》2019,45(11):14153-14159
Highly dense (>98%) and nanograined (∼60 nm) gadolinia doped ceria are obtained from ultrafine powders by adopting two-step sintering (TSS) procedure at an ultralow temperature of 750 °C with a dwell time of 20 h, which is the lowest sintering temperature for ceria family without sintering aids up to now. Electrochemical impedance spectroscopy investigations suggest that the electrical conductivities of densified electrolytes are closely related to sintering temperature and grain size, and GDC900-750 exhibits the highest total electrical conductivity of 3.640 S m−1 at 700 °C in air. Fitting calculation indicates partial grain-size dependence of oxygen vacancy association enthalpy and grain-size independence of oxygen ion migration enthalpy. Grain boundary maturity influences on grain boundary conductivity to some extent, and younger grain boundary endues the densified electrolytes with higher grain boundary conductivity. 相似文献
70.
Sc2O3-W matrix dispenser cathodes have been prepared by powder metallurgy method and tested in Pierce electron guns.The emission current density can reach 72 A/cm2 at 900C and over 100 A/cm2 can be achieved at a temperature higher than 950C.The emission improves and then keeps stable with time throughout the life testing period of 330 h at a continuous loading of 88 A/cm2pulsed current density with a pulse width of 10μs and duty cycle of 0.2%.The cathode surface is covered by a semiconductor multilayer composed of Ba,Sc and O.The emission behavior of the cathode can be explained by a semiconductor model. 相似文献