低损耗中高压陶瓷电容器国产化研究(Ⅳ)——工业化生产的应用研究

通过采用高速离心喷雾干燥造粒、无边镀Ni-Sn电极、阻燃性环氧树脂包封和可靠性工艺控制方法等一系列工业化生产的应用研究成果,实现了把实验室研究成果尽快推广应用到工业化批量生产的目的,完成了低损耗中高压陶瓷电容器国产化的全部研究工作。     

低损耗中高压陶瓷电容器国产化研究(Ⅱ)——结构模型和计算模拟

提出在化学组成不同的两种煅烧料共混制得的陶瓷材料中可能存在“两相结构”与“壳芯结构”共存的化学不均匀分布状态。电子计算机模拟的结果表明,合理控制工艺条件可以使陶瓷材料的介电温谱呈现“双峰效应”,满足彩电国产化对中高压陶瓷电容器的多方面性能要求。     

纳滤在制备高浓度活性红3BS中的应用

对活性红3BS染料进行了纳滤中试实验。结果表明,利用合适的纳滤膜对该染料进行脱盐浓缩是可行的。该方法不仅可以大幅度降低染料合成浆液中的无机盐含量,并可对染料浆液浓缩达3倍左右,使染料的着色强度和含固量明显提高;染料的损失率极低,同时对副染料也可以部分脱除。     

Ce3+-Gd3+ co-doped high efficiency oxide glasses and transfer efficiency from Gd3+ to Ce3+

The rare earth Ce3+ ion doped SiO2-B2O3-BaO-Gd2O3 system is synthesized by high-temperature melting method. The density, transmission, excitation spectra and scintillating properties of the glasses are investigated. The results indicate that all the samples have good physical and scintillating properties. The emission peak wavelength of all samples is 390 nm under X-ray radiation. Gd3+ ions have a negative impact on scintillating properties when its concentration reaches a certain level. Gd3+ ions sensitize the luminescence of Ce3+ ions, and the ideal concentration is 15 mol% for Gd3+ ions. Also the decay characteristics of Ce3+ and Gd3+ ions are investigated. These samples have potential practical applications in high energy physics.     

Ni2＋掺杂CdWO4晶体的发光特性研究

应用坩埚下降法成功地生长出了Ni 2＋掺杂的CdWO4单晶。测定了晶体的吸收与荧光光谱。根据晶体分裂场理论和吸收特性,计算了Ni 2＋在该Cd-WO4晶体中的晶格场分裂参量Dq=1054cm-1、Racah参量B=1280cm-1与C=5982cm-1。在314nm光的激发下,观察到发光中心为480nm的蓝光,这是Cd-WO4晶体中WO66＋中的电子跃迁所致。在808与980nm的激发下,均观察到发光中心分别为1068nm的近红外发射带,归结为和Ni 2＋八面体格位的3 T2g（3F）→3 A2g（3F）能级跃迁。     

Fe：Mn：LiNbO3晶体的生长及光学性能研究

采用坩埚下降法生长了掺杂Fe^3＋和Mn^2＋的LiNbO3单晶。晶体经极化处理后,用X-射线衍射仪测试了晶体的晶格常数,讨论了掺杂离子对晶格常数的影响。利用二渡耦合实验测试了晶体的指数增益系数、衍射效率和响应时间,结果表明：Fe：Mn：LiNbO3晶体的最大指数增益系数达到40cm^-1,Fe：Mn：LiNbO3的最大衍射效率分别为76％,二波耦合响应时间为2．5min。Fe：Mn：LiNbO3是一种性能优良的光折变晶体。     

纳米羟基磷灰石的新型超声喷雾法制备技术研究

在常温常压下,以硝酸钙(Ca(NO3)2·4H2O)和磷酸氢二铵((NH4)2HPO4)为原料,运用超声喷雾法技术制备了羟基磷灰石(HAP)纳米粉体,获得了颗粒度为30～40nm的均匀HAP粉体.研究了化学反应时间与烧结温度对HAP的结晶度和颗粒均匀性的影响规律.在相同的制备工艺条件下,与传统的超声化学法和化学沉淀法制得的HAP粉体样品进行比较,发现超声喷雾法可以在较短的反应时间内制备出纳米HAP,显著提高HAP的合成效率、结晶度,且获得的颗粒度相对均匀.     

Fluorescence Properties of Eu~(3+) Doped in Na_5Lu_9F_(32) Single Crystals

Eu~(3+) ion doped cubic Na_5Lu_9F_(32) single crystals with high quality were synthesized by a modified Bridgman method by using a high 70-90 ℃/cm temperature gradient for cross solid-liquid interface. The optical spectroscopic investigations of the obtained single crystal were reported for the absorption, excitation and emission. The experimental results show that a strong red emission at 609 nm attributing to the ~5D_0→~7F_2 transition of Eu~(3+) doped Na_5Lu_9F_(32) single crystals can be obtained under the excitation of 394 nm light and reach the maximum when the Eu~(3+) doping concentration is 4 mol% in present research. The local covalent is enhanced and symmetry is reduced with the increase of Eu~(3+) concentrations inferring from the strength parameters Ω_2 and Ω_4 calculated by their measured emission spectra. The CIE chromaticity coordinates of the 4 mol% Eu~(3+) doped Na_5Lu_9F_(32) single crystals are calculated as(x=0.626, y=0.3736), which are close to the NTSC standard values for red(x=0.67, y=0.33). The experimental results reveal that the single crystal can be used as potential red phosphors under near ultraviolet(NUV) light excitation.