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81.
Shintaro Nakano Nobuyoshi Saito Kentaro Miura Tatsunori Sakano Tomomasa Ueda Keiji Sugi Hajime Yamaguchi Isao Amemiya Masato Hiramatsu Arichika Ishida 《Journal of the Society for Information Display》2012,20(9):493-498
We have successfully reduced threshold voltage shifts of amorphous In–Ga–Zn–O thin‐film transistors (a‐IGZO TFTs) on transparent polyimide films against bias‐temperature stress below 100 mV, which is equivalent to those on glass substrates. This high reliability was achieved by dense IGZO thin films and annealing temperature below 300 °C. We have reduced bulk defects of IGZO thin films and interface defects between gate insulator and IGZO thin film by optimizing deposition conditions of IGZO thin films and annealing conditions. Furthermore, a 3.0‐in. flexible active‐matrix organic light‐emitting diode was demonstrated with the highly reliable a‐IGZO TFT backplane on polyimide film. The polyimide film coating process is compatible with mass‐production lines. We believe that flexible organic light‐emitting diode displays can be mass produced using a‐IGZO TFT backplane on polyimide films. 相似文献
82.
Hillel Tal-Ezer 《Journal of scientific computing》1989,4(1):25-60
In solving a mathematical problem numerically, we frequently need to operate on a vector by an operator that can be expressed asf(A), whereA is anN ×N matrix [e.g., exp(A), sin(A), A–-]. Except for very simple matrices, it is impractical to construct the matrixf (A) explicitly. Usually an approximation to it is used. This paper develops an algorithm based upon a polynomial approximation tof (A). First the problem is reduced to a problem of approximatingf (z) by a polynomial in z, where z belongs to a domainD in the complex plane that includes all the eigenvalues ofA. This approximation problem is treated by interpolatingf (z) in a certain set of points that is known to have some maximal properties. The approximation thus achieved is almost best. Implementing the algorithm to some practical problems is described. Since a solution to a linear systemAx=b isx=A
–1
b, an iterative solution algorithm can be based upon a polynomial approximation tof (A)=A
–1. We give special attention to this important problem. 相似文献
83.
Experimental vapor pressures andP--T data of an important alternative refrigerant, 1, 1-difluoroethane (HFC-152a), have been measured by means of a constant-volume method coupled with expansion procedures. SixtyP--T data were measured along eight isochores in a range of temperaturesT from 330 to 440 K, at pressuresP from 1.6 to 9.3 MPa, and at densities from 51 to 811 kg·m–3. Forty-six vapor pressures were also measured at temperatures from 320 K to the critical temperature. The uncertainties of the temperature and pressure measurements are within ±7mK and ±2kPa, respectively, while the uncertainty of the density values is within ±0.1%. The purity of the sample used is 99.9 wt%. On the basis of the measurements along each isochore, five saturation points were determined and the critical pressure was determined by correlating the vapor-pressure measurements. The second and third virial coefficients for temperatures from 360 to 440 K have also been determined. 相似文献
84.
分析了人民币汇率机制改革中选择“参考一篮子货币”制的原因;在肯定这次汇率制度改革给我国带来的有利影响,同时指出了参考一篮子货币制在短期内将面临的问题,并进一步提出关于完善该汇率制度的相关措施和建议,以期对我国汇率制度改革提供参考。 相似文献
85.
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88.
锑在现代工业体系中占有重要地位,快速准确测定锑矿中锑含量对锑矿的采选具有重要指导意义。云南某矿山锑矿以萤石为主要伴生矿,现有的盐酸、硝酸、氢氟酸和高氯酸混酸体系无法彻底分解样品,而采用碱熔处理流程长且引入大量基体,均无法满足准确快速测定的要求。选择硫酸-氢氟酸混酸体系分解样品,再用酒石酸-盐酸混合溶液加热浸取,锑完全溶解于溶液中,选择Sb 206.833{463}nm为分析谱线,使用电感耦合等离子体原子发射光谱法(ICP-AES)测定锑。结果表明,锑的质量浓度在5.0~80 μg/mL范围内与其发射强度呈良好的线性关系,校准曲线线性相关系数r=0.999 8;方法的检出限为0.012 μg/mL。按照实验方法对锑矿石成分分析标准物质和锑矿选矿流程样品中锑进行测定,结果的相对标准偏差(RSD,n=5)为0.71%~5.7%;标准物质的认定值和测定值相一致;锑矿选矿流程样品中锑的加标回收率为97%~102%,满足国家地质矿产行业标准DZ/T 0130—2006的要求。 相似文献
89.
Cr3Si/Crl3Ni5Si2金属间化合物合金组织与高温滑动磨损性能的研究 总被引:2,自引:0,他引:2
利用水冷铜模激光熔炼炉制得了由初生枝晶Cr3Si和枝晶间Cr3Si/Crl3Ni5Si2共晶组成的金属间化合物合金。利用OM,SEM,TEM,EDS和XRD分析了该金属间化合物的显微组织,在400℃,500℃和600℃条件下测试了其耐磨性能。结果表明,由于Cr3Si和Crl3NisSi2硬度高、原子键合力强、组织细小、均匀,在高温滑动磨损条件下具有优良的耐磨性能。 相似文献
90.
The effect of SO2 on catalytic activity for NO reduction to N2 by methanol in excess oxygen over $\gamma$ -alumina has been investigated. SCR activity increased initially upon exposure of a fresh $\gamma$ -alumina catalyst to SO2 which is attributed to formation of Brønsted acid sites. Longer exposure to SO2 leads to a decline in catalytic activity to a lower steady-state NOx reduction activity which is independent of the SO2 content in the feed gas. 相似文献