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排序方式: 共有93条查询结果,搜索用时 15 毫秒
1.
Dependence of Performance of Organic Light-emitting Devices on Sheet Resistance of Indium-tin-oxide Anodes 总被引:2,自引:0,他引:2
ZHOU Liang ZHANG Hong-jie YU Jiang-bo MENG Qing-guo PENG Chun-yun LIU Feng-yi DENG Rui-ping PENG Ze-ping LI Zhe-feng 《高等学校化学研究》2006,22(4):427-431
IntroductionIndium-tin-oxide(ITO) has been widely used asthe anode material in organic light-emitting devices(OLEDs) because of its high transmittance in the visi-ble region and low electrical resistivity. In the pastyears, many investigations focused on … 相似文献
2.
采用有限元分析法对飞秒激光冲击AZ31B镁合金进行数值模拟,研究了激光冲击处理对镁合金变形过程的影响,分析了单脉冲激光冲击下材料内部的位移、动能、应力和应变的分布情况,得到了材料的瞬态速度和应变率变化过程.仿真结果表明,单脉冲飞秒激光冲击镁合金产生的塑性变形,可在材料表面形成微米级凹坑,中心点处最大位移为34μm,最大变形速度390m/s;在冲击初期,材料表面的应力和应变主要分布在冲击区域中心节点和边缘附近,并且得到镁合金的最大应力和最大应变率分别为955 MPa和1.8×106 s-1.研究结果能够为深入分析飞秒激光与镁合金作用时材料变形参量的变化规律提供数值理论依据. 相似文献
3.
提 要设 是定义在[0,1]上的随机过程X(t)的n个等距独立观察值,其中, 服从公共连续分布F;,服从公共连续分布 F*,F与F*不同;其中,是过程 X(t)的变点.用CUSUM及Brownian Sheet方法给出了检测变点τ位置的一个程序,并证明了所得结果是强相合的;同时也讨论了τ的假设检验和区间估计. 相似文献
4.
Hai Wang Yong Liu Hong Huang Minyi Zhong Hui Shen Yuanhao Wang Hongxing Yang 《Applied Surface Science》2009,255(22):9020-9025
Low resistance dye-sensitized solar cells (DSSCs) based on all-titanium substrates were proposed in this paper. To minimize the internal resistance of DSSCs, the titanium wires and titanium sheets were used as the substrates of the photoanode and the counter electrode, respectively. Compared with the FTO substrate, titanium wires could absorb much diffused light by back reflection since the reflectivity in the titanium sheet was highly increased up to 53.12%. Furthermore, the transmittance of the front cover was increased by 13.2% using the super white glass instead of FTO substrate. The thickness of TiO2 thin film coated on titanium wire was optimized to achieve a high cell performance. The efficiency of 5.6% for the cell was obtained with a Jsc of 15.41 mA cm−2, Voc of 0.59 V, and FF of 0.62. The results showed that the titanium-based DSSCs had superiority for producing the large-scale DSSCs without metal grid line. 相似文献
5.
搭建了光纤光栅检测超声应力波系统,并阐述其工作原理,以动态应变与光纤光栅中心波长漂移量间关系为基础,推导得出输出电压与板中应变成线性关系.采用超声信号发生器发射28kHz的脉冲信号激励超声振子,通过有机玻璃楔形块将激励传递至5052铝合金薄板产生超声应力波,并利用光纤光栅应变传感器对其进行探测.在板上开一98mm长裂缝,测得超声应力波中出现新的波包,通过计算损伤前后新增波包到来的时间差确定裂缝位置,所测结果与实际位置偏差为2.7mm.该实验表明光纤光栅可代替超声探头来实现对低频超声波的探测. 相似文献
6.
In the present paper the diffuse and localized necking models according to Swift [Swift, H.W., 1952. Plastic instability under plane stress, Journal of the Mechanics and Physics of Solids, 11–18], Hill [Hill, R., 1952. On discontinuous plastic states, with special reference to localized necking in thin sheets. Journal of the Mechanics and Physics of Solids 1, 19–30] and Marciniak and Kuczyński [Marciniak, Z., Kuczyński, K., 1967. Limit strains in the process of stretch-forming sheet metal. International Journal of Mechanical Sciences 9, 609–620], respectively, are considered. A theoretical framework for the mentioned models is proposed that covers rigid–plastic as well as elastic–plastic constitutive modelling using various advanced phenomenological yield functions that are able to account very accurately for plastic anisotropy. The mentioned necking models are applied to different orthotropic sheet metals in order to assess their predictive capabilities and to stress out some potential sources for discrepancies between simulations and experiments. In particular, the impact of the applied hardening curve and the equibiaxial r-value, which was recently introduced by Barlat [Barlat, F., Brem, J.C., Yoon, J.W., Chung, K., Dick, R.E., Choi, S.-H., Pourboghrat, F., Chu, E., Lege, D.J., 2003. Plane stress yield function for aluminium alloy sheets – part 1: theory. International Journal of Plasticity 19, 297–1319], on formability prediction is investigated. Furthermore, the impact of the Portevin–LeChatelier effect on the formability of aluminum sheet metals is discussed. 相似文献
7.
Transformation of flow turbulence structure with cavitation occurrence, determination of the flow conditions favorable for nucleation of cavitation bubbles, influence of the statistical structure of turbulence on this process and the inverse effect of cavitation on the flow dynamics are challenging problems in modern fluid mechanics. The paper reports on the results of statistical processing of the velocity fields measured by a PIV technique in cavitating flow over a 2D symmetric hydrofoil for four flow conditions, starting from a cavitation-free regime and finishing by unsteady cloud cavitation. We analyze basic information on the statistical structure of velocity fluctuations in the form of histograms and Q-Q diagrams along with profiles of the mean velocity and turbulent kinetic energy. The research reveals that the flow turbulence pattern and distributions of turbulent fluctuations change significantly with the cavitation development. Under unsteady cloud cavitation conditions, the probability density function of the fluctuating velocity has a two-mode distribution, which indicates switching of two alternating flow conditions in a region above the hydrofoil aft part due to periodic passing of cavitation clouds. Behaviors of the mean and most probable velocities unexpectedly appear to be different with a monotonous increase of the incoming flow velocity. This finding must be caused by modification of the skewness coefficient of the fluctuating velocity. 相似文献
8.
Hassan Chataoui Hasna Choukri Mohamed Maatallah Driss Cherqaoui Abdellah Jarid 《Current Applied Physics》2017,17(10):1310-1315
Bending of the A = A (A of the group IVA) double bond neighboring is rationalized by the hyperconjugation phenomenon analysis. The bending is also observed for the high sized linear, cyclic or graphene-like compounds that imply the conjugated double bonds. The electronic delocalization takes place between occupied σ(π) and unoccupied π*(σ*) orbitals especially for compound implying Si and Ge atoms. Leading to rippled structure, this phenomenon affects the silicene and germane thickness sheets and probably would have some consequences on the properties of such compounds when they will be involved in the industries in the future. However we introduce a new parameter to assess the thickness of graphenic structures when the hyperconjugation takes place in the bonding framework. The study has been undertaken at high levels of theory like B3LYP/6-311 + G(3df,2p). 相似文献
9.
Deep level transient spectroscopy has been used to observe the reduced concentrations of vacancy-related defects in γ-irradiated n-type Si containing hydrogen atoms. Data are presented on the efficiency and depth of this damage reduction as a function of the duration and temperature of the exposure to the plasma used to introduce the atomic hydrogen. A 3-hour exposure in an H plasma at 300°C prior to irradiation reduced the concentrations of the O-V, V-V and P-V centres by half or more to a depth of ~20 μm, compared to the control samples. 相似文献
10.