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101.
从势和场的观点出发讨论了带电粒子在应变超晶格中的运动行为.在经典力学框架内和偶极近似下,引入正弦平方势,把粒子运动方程化为具有阻尼项和混合激励项的广义摆方程.利用Melnikov方法讨论了系统的临界性质与混沌行为.结果表明,系统的混沌行为与它的参数有关,适当调节参数,就可以原则上保证系统的稳定性. 相似文献
102.
A new voltage-programmed driving scheme named the mixed parallel addressing scheme is presented for AMOLED displays, in which one compensation interval can be divided into the first compensation frame and the consequent N-1 post-compensation frames without periods of initialization and threshold voltage detection. The proposed driving scheme has the advantages of both high speed and low driving power due to the mixture of the pipeline technology and the threshold voltage one-time detection technology. Corresponding to the proposed driving scheme, we also propose a new voltage-programmed compensation pixel circuit, which consists of five TFTs and two capacitors(5T2C). In-Zn-O thin-film transistors(IZO TFTs) are used to build the proposed 5T2C pixel circuit. It is shown that the non-uniformity of the proposed pixel circuit is considerably reduced compared with that of the conventional 2T1C pixel circuit. The number of frames(N) preserved in the proposed driving scheme are measured and can be up to 35 with the variation of the OLED current remaining in an acceptable range. Moreover, the proposed voltage-programmed driving scheme can be more valuable for an AMOLED display with high resolution, and may also be applied to other compensation pixel circuits. 相似文献
103.
Tae Hoon Lee Aydin Ozcan Inho Park Dong Fan Jun Kyu Jang Paulo G. M. Mileo Seung Yeon Yoo Ji Soo Roh Jun Hyeok Kang Byung Kwan Lee Young Hoon Cho Rocio Semino Hyo Won Kim Guillaume Maurin Ho Bum Park 《Advanced functional materials》2021,31(38):2103973
Incorporation of defects in metal–organic frameworks (MOFs) offers new opportunities for manipulating their microporosity and functionalities. The so-called “defect engineering” has great potential to tailor the mass transport properties in MOF/polymer mixed matrix membranes (MMMs) for challenging separation applications, for example, CO2 capture. This study first investigates the impact of MOF defects on the membrane properties of the resultant MOF/polymer MMMs for CO2 separation. Highly porous defect-engineered UiO-66 nanoparticles are successfully synthesized and incorporated into a CO2-philic crosslinked poly(ethylene glycol) diacrylate (PEGDA) matrix. A thorough joint experimental/simulation characterization reveals that defect-engineered UiO-66/PEGDA MMMs exhibit nearly identical filler–matrix interfacial properties regardless of the defect concentrations of their parental UiO-66 filler. In addition, non-equilibrium molecular dynamics simulations in tandem with gas transport studies disclose that the defects in MOFs provide the MMMs with ultrafast transport pathways mainly governed by diffusivity selectivity. Ultimately, MMMs containing the most defective UiO-66 show the most enhanced CO2/N2 separation performance—CO2 permeability = 470 Barrer (four times higher than pure PEGDA) and maintains CO2/N2 selectivity = 41—which overcomes the trade-off limitation in pure polymers. The results emphasize that defect engineering in MOFs would mark a new milestone for the future development of optimized MMMs. 相似文献
104.
本文介绍了电话机来电显示电路CSC9270DGP的测试原理和方法,CSC9270DGP是一个完整的双音多频接收电路,具有频带分离滤波器和数字解码功能。重点介绍了该电路在ETS-570大规模测试系统上的测试软件开发。CSC9270DGP是一个数模混和电路,有3/4是模拟部分,本文介绍了如何在数字系统上测试模拟电路的方法。 相似文献
105.
研究一种语音伪装新方法,将保密语音替换成另外一种语音以便于在公网上安全传输。保密语音经2.4kb/低速率压缩编码后,依据设计的客观音质评估模型,将参数隐蔽地嵌入普通语音;检测时利用逆过程恢复保密语音。实验表明算法的信噪比较传统算法提高约3.5dB,并在受到压缩、滤波等攻击时具有较高的鲁棒性。 相似文献
106.
There is an increasing need to develop stable, high-intensity, efficient OLEDs in the deep blue and UV. Applications include blue pixels for displays and tunable narrow solid-state UV sources for sensing, diagnostics, and development of a wide band spectrometer-on-a-chip. With the aim of developing such OLEDs we demonstrate an array of deep blue to near UV tunable microcavity (μc) OLEDs (λ ∼373–469 nm) using, in a unique approach, a mixed emitting layer (EML) of poly(N-vinyl carbazole) (PVK) and 4,4′-bis(9-carbazolyl)-biphenyl (CBP), whose ITO-based devices show a broad electroluminescence (EL) in the wavelength range of interest. This 373–469 nm band expands the 493–640 nm range previously attained with μcOLEDs into the desired deep blue-to-near UV range. Moreover, the current work highlights interesting characteristics of the complexity of mixed EML emission in combinatorial 2-d μcOLED arrays of the structure 40 nm Ag/x nm MoOx/∼30 nm PVK:CBP (3:1 weight ratio)/y nm 4,7-diphenyl-1,10-phenanthroline (BPhen)/1 nm LiF/100 nm Al, where x = 5, 10, 15, and 20 nm and y = 10, 15, 20, and 30 nm. In the short wavelength μc devices, only CBP emission was observed, while in the long wavelength μc devices the emission from both PVK and CBP was evident. To understand this behavior simulations based on the scattering matrix method, were performed. The source profile of the EML was extracted from the measured EL of ITO-based devices. The calculated μc spectra indeed indicated that in the thinner, short wavelength devices the emission is primarily from CBP; in the thicker devices both CBP and PVK contribute to the EL. This situation is due to the effect of the optical cavity length on the relative contributions of PVK and CBP EL through a change in the wavelength-dependent emission rate, which was not suggested previously. Structural analysis of the EML and the preceding MoOx layer complemented the data analysis. 相似文献
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伴随着教育信息化和混合式教学的浪潮,许多课程都开始了信息化的教学改革。本文以《移动商务》课程为例,从课程定位、课程目标、课程设计、课程实施、课程评价五个方面对该课程的信息化教学予以总结,希望进一步提高《移动商务》课程的教学效果。 相似文献