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91.
93.
我们开发了用于全彩色OLED的高效荧光添加剂。对于蓝色、绿色和红色的OLED来说,在10mA/cm^2时分别实现了8.7cd/A,20.5cd/A和11.4cd/A的电流效能。蓝色器件在1,000cd/mz的起始亮度时,寿命估计为23,000个小时。此外,绿色和红色器件的寿命估计长达100,000小时。通过使用这些添加剂,我们期望在一个300cd/m^2的白光中能够实现一个寿命为18,000小时的全彩色OLED显示器。 相似文献
94.
95.
基于"有效电容"的概念提出了一种分析两相邻耦合RC互连延时的方法.与采用Miller电容的传统方法比较,该方法不但提高了计算精度而且反映出了延时随信号上升时间的变化规律.该方法与Elmore延时法具有相同的计算复杂度,可广泛用于考虑耦合电容的面向性能的布线优化. 相似文献
96.
97.
病态分析体系有偏估计的研究 总被引:3,自引:0,他引:3
运用广义岭估计和Liukejian提出的有偏估计,对病态分析体系进行了数值模拟和实际光度测定,结果表明,广义岭估计显优于最小二乘估计,Liukejian法有功效,可和为解析病态分析体系的化学计量学方法。 相似文献
98.
具有超大通道结构的介孔氧化硅柱层状钛酸的合成和催化应用初探 总被引:6,自引:0,他引:6
A mesoporous (d=2.3mm) silica-pillared layered tetratitanate with a super gallery (d001=1.84mm)was prepared by first preswelling layered tetratitanate with n-dodecyl amine, then reacting with 20wt% NH2(CH2)3Si(OC2H5)3 aqueous solution, and finally calcinating the resultant solid product in air at 550℃. All the reaction was carried out hydrothermally in an autoclave at 130℃. The obtained material has a relatively high BET surface area of 204m2·g-1 and a thermal stability beyond 600℃. The catalytic application of the material was also investigated by using the dehydration of isopropanol and the reform of n-hexane as two probing reactions. 相似文献
99.
The molecular electronegativity-distance vector (MEDV) was used to describe the molecular structure of volatile components of Rosa banksiae Ait, and QSRR model was built up by use of multiple linear regression (MLR). Furthermore, in virtue of variable screening by the stepwise multiple regression technique, the QSRR models of 10 and 6 variables and linear retention index (LRI) 10, 7 and 6 varieables were built up by combinating MEDV with the Ultra2 column GC retention time (tR) of 53 volatile components of Rosa Banksiae Air. The multiple correlation coefficients (R) of modeling calculation values of QSRR model were 0.906, 0.906, 0.949, 0.943 and 0.949, respectively. The cross-verification multiple correlation coefficients (RCV) were 0.903, 0.904, 0.867, 0.901 and 0.904, respectively. The results show that the models constructed could provide estimation stability and favorable predictive ability. 相似文献
100.
A novel correlation for estimation of hydrate forming condition of natural gases 总被引:1,自引:0,他引:1 下载免费PDF全文
An inherent problem with natural gas production or transmission is the formation of gas hydrates, which can lead to safety hazards to production/
transportation systems and to substantial economic risks. Therefore, an understanding of conditions where hydrates form is necessary to
overcome hydrate related issues. Over the years, several models requiring more complicated and longer computations have been proposed for
the prediction of hydrate formation conditions of natural gases. For these reasons, it is essential to develop a reliable and simple-to-use method
for oil and gas practitioners. The purpose of this study is to formulate a novel empirical correlation for rapid estimation of hydrate formation
condition of sweet natural gases. The developed correlation holds for wide range of temperatures (265–298 K), pressures (1200 to 40000 kPa)
and molecular weights (16−29). New proposed correlation shows consistently accurate results across proposed pressure, temperature and
molecular weight ranges. This consistency could not be matched by any of the widely accepted existing correlations within the investigated
range. For all conditions, new correlation showed average absolute deviation to be less than 0.2% and provided much better results than the
widely accepted existing correlations. 相似文献