E.E.Shaisha
,
Sh.F.El-Desouki
,
I.Shaltout
,
A.A.Bahgat
材料科学技术（英文）
A new glass system (Bi2O3)50(Fe2O3)10(Li2O)x(K2O)40-x, where x changes in steps of 5 mole fraction between 0 and 40, was selected to study the electrical relaxation and the mixed alkali effect (MAE) phenomena. Measurements of ac conductivity σac, dielectric permittivity ε' and loss factor tan± in the frequency range of 0.12~102 kHz and in the temperature range of 300~650 K were carried out. The temperature dependence of the ac conductivity shows a slow increasing rate at low temperature and high frequency and a rapid increase at high temperature and low frequency. At constant temperature, the ac conductivity is found to be proportional to ωs, where s is the frequency exponent, which is less than 1. Analysis of the conductivity data and the frequency exponent shows that the overlapping large polaron tunnelling (OLPT) model of ions is the most favorable mechanism for the ac conduction in the present glass system. The ac response, the dc conductivity and dielectric relaxation have the same activation energy and they originate from the same basic transport mechanism. The results of the dielectric permittivity show no maximum peak in the temperature and frequency range studied. This absence of maximum peak is an indication of non-ferroelectric behavior of all the studied samples. The MAE has been detected in the ac conductivity, which is the same as the classical MAE in the dc conductivity. The electrical parameters such as dielectric permittivity ε' and real dielectric modulus M' show a typical minimum deviation from linearity by about two orders of magnitude. The loss factor tanδ and the imaginary dielectric modulus M" are insignificantly dependent on composition even at the same transition temperature Tg.
关键词:
Dielectric permittivity
,
null
,
null
,
null
丁卫撑
,
王义
,
李元景
,
王敏
,
方方
液晶与显示
doi:10.3969/j.issn.1007-2780.2009.06.024
介绍了基于SH1123驱动器的OLED点阵图形显示模块,给出了模块与微处理器C8051F340的硬件接口电路,简要分析了SH1123的指令系统,对C语言编程环境下模块底层驱动程序的实现进行了重点阐述,并给出如何利用按键实现显示菜单控制的方法.
关键词:
微处理器
,
接口
,
驱动程序
,
OLED显示
李文连
液晶与显示
doi:10.3969/j.issn.1007-2780.2002.01.005
通过比较有机EL与无机EL、LCD在平板显示应用方面的差异,展示了OELD的美好应用前景.由于无机薄膜EL缺乏高亮度蓝基色成分以及驱动电压是100V左右的交流,难于制成低压彩色超薄显示器;无机分散型EL屏采用的是十几微米厚的粉末材料,也难于制成高分辨率超薄显示器,因此它们都无法与OELD相比.OELD显示器体积可以是LCD的1/2,功耗也大大低于LCD,所以OELD将有望取代LCD.评述了当前OELD的最新发展趋势:采用荧光染料掺杂式的模糊界面结构的电致荧光器件和采用荧光染料掺杂式的电致磷光器件是当前OELD发展的主要潮流.文中还评述了采用低折射率材料提高外量子效率的情况.
关键词:
电致发光
,
磷光
,
发光平板显示
耿卫东
,
张永利
,
刘艳艳
,
代永平
,
孙钟林
液晶与显示
doi:10.3969/j.issn.1007-2780.2005.06.016
介绍了可编程多通道TFT-LCD参考电压发生器专用电路EL-5825的工作原理、特点及应用.利用C8051F330单片机控制EL-5825设计了一种基于LCoS芯片的头盔显示系统电路,该设计方案具有电路结构简单、外围器件少、系统结构微型化等特点,有利于实现系统的轻便灵活,提高整机性能.介绍了硬件接口电路的设计方法,给出了单片机软件流程图.
关键词:
平板显示器
,
TFT-LCD
,
EL-5825
,
参考电压
,
SPI串行接口
朱向情
,
陈强
,
庞荣清
,
陈翠竹
,
王强
,
陈佳
,
陈庆华
,
潘兴华
材料导报
doi:10.11896/j.issn.1005-023X.2014.22.012
利用透明质酸钠(Sodium hyaluronate,简称SH)和魔芋葡甘聚糖(Konjac glucomannan,简称KGM)制备共混膜SH/KGM,通过膜的干预减少或阻止硬膜外瘢痕的形成.选择人皮肤成纤维细胞为种子细胞,采用流式细胞术和半定量PCR方法检测细胞的纯度;通过体外移植的方法将成纤维细胞移植到SH/KGM共混膜表面,细胞形态学观察发现细胞由原来的梭形变成不规则的圆形,且细胞能够粘附于SH/KGM共混膜的表面,但移植细胞在移植后的2天、5天和7天内均没有观察到增殖.这种现象表明共混膜SH/KGM具有防止硬膜外瘢痕粘连的作用,可以作为腰椎手术的介入材料.
关键词:
皮肤成纤维细胞
,
透明质酸钠
,
魔芋葡甘聚糖
,
共混膜
,
瘢痕
