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991.
Eugene Wai Keong Koh Cheng Hsin Chiu Yao Kun Lim Yong-Wei Zhang Hui Pan 《International Journal of Hydrogen Energy》2012
We investigate the hydrogen adsorption on and diffusion through the MoS2 monolayer based on density-functional theory. We show that the hydrogen atom prefers to bond to the S atom at the monolayer, leading to enhanced conductivity. The hydrogen atom can also adsorb at the middle of the hexagon ring by overcoming an energy barrier of 0.57 eV at a strain of 8%. Also, we show that the MoS2 monolayer is flexible and any mechanical deformation of the monolayer is reversible because the extension of the Mo–S bond is much smaller than the applied strain. The monolayer can block the diffusion of hydrogen molecule from one side to the other due to a high energy barrier (6.56 eV). However, the barrier can be reduced to 1.38 eV at a strain of 30% and even totally removed by creating S vacancies and applying a strain of 15%. The MoS2 monolayer may find applications in sensors to detect hydrogen, and as mechanical valve to control the concentration of hydrogen gas. 相似文献
992.
Yao Zhang 《Petroleum Science and Technology》2016,34(13):1180-1186
Air injection has been used for decades as an enhanced oil recovery method. An oxidation kinetics study is important for the application of air injection. Low-temperature oxidation is more feasible in light oil reservoirs. Although an experiment using a small batch reactor has been conducted before, the reaction order with respect to the oxygen partial pressure was not well studied. The authors use a small batch reactor to study the effect of temperature and pressure on the oxygen consumption rate of the Wolfcamp light oil. The reaction order, the activation energy, and Arrhenius constant are calculated. 相似文献
993.
For 32/22 nm technology nodes and below, double patterning (DP) lithography has become the most promising interim solutions due to the delay in the deployment of next generation lithography (e.g., EUV). DP requires the partitioning of the layout patterns into two different masks, a procedure called layout decomposition. Layout decomposition is a key computational step that is necessary for double patterning technology. Existing works on layout decomposition are all single-threaded, which is not scalable in runtime and/or memory for large industrial layouts. This paper presents the first window-based parallel layout decomposition methods for improving both runtime and memory consumption. Experimental results are promising and show the presented parallel layout decomposition methods obtain upto 21× speedup in runtime and upto 7.5×reduction in peak memory consumption with acceptable solution quality. 相似文献
994.
This paper conducts a comprehensive study of the Lagrangian-based hydrodynamic model with application to highway state estimation. Our analysis is motivated by the practical problems of freeway traffic monitoring and estimation using multi-source data measured from mobile devices and fixed sensors. We conduct rigorous mathematical analysis on the Hamilton-Jacobi representation of the Lighthill-Whitham-Richards model in the transformed coordinates, and derive explicit and closed-form solutions with piecewise affine initial, boundary, and internal conditions, based on the variational principle. A numerical study of the Mobile Century field experiment demonstrates some unique features and the effectiveness in traffic estimation of the Lagrangian-based model. 相似文献
995.
996.
宁波杭州湾新区跨十塘横江桥小拱塔采用了抛物线形设计,施工过程是将钢结构节段吊装拼接而形成主塔曲线,因此,对于主塔完成后的拱形评定显得很有必要。本文中,利用全站仪测量主塔小拱柱拼接时每段钢结构节段上口角点坐标数据,通过坐标转换方法将角点坐标数据投影到小塔拱中心轴线所在平面上,再利用整体最小二乘方法对线形和平面进行了拟合。拟合结果显示出完工线形与设计线形符合度很好,对工程的竣工具有一定的参考意义。 相似文献
997.
介绍了一种基于dsPIC30F6014单片机控制的三相晶闸管触发实验装置,详细阐述了其软硬件结构。测试实验证明,该装置电路简单,产生的触发脉冲稳定性好、触发精度高、易于调试、操作方便、具有实用价值,能够进一步开发用于实验教学。 相似文献
998.
In the chemical industry, real‐time flooding prognosis is a necessity for packed‐column operation because the flooding phenomenon interferes with the performance of production systems. In this work, the profile monitoring technique is utilized to capture the dynamic behavior of pressure drop, which is an important indicator for the flooding phenomenon. In each moving window, the pressure drop signals are described by using an exponential generalized autoregressive conditional heteroskedastic model. The onset of the flooding phenomenon is then indicated by changes in model parameters. Moreover, to efficiently capture the process change, a nonparametric approach is utilized to establish a statistical control chart. Experimental and comparison results show the advantages of the proposed method. 相似文献
999.
Changgeng Liu Beatrice Pazzucconi Juan Liu Xincheng Yao 《Journal of Modern Optics》2019,66(12):1311-1317
We demonstrated the feasibility of using a holographic waveguide imager for eye tracking. A holographic waveguide placed in front of the eye was used to capture images of the anterior segment of the eye and to guide the images to a camera distant from the eye. The pupil centre (PC) and corneal reflection (CR) of the eye was used to compute eye position. A custom-built model eye was used to validate the prototype eye tracker. A linear relationship between the angular eye position and the PC/CR vector was found over 60 horizontal degrees and 40 vertical degrees. The tracking accuracy and precision were 0.72 degree and 0.50 degree over these tracking ranges. These results confirmed that holographic waveguide could be a viable platform for developing compact, wearable, see-through eye trackers that can continuously monitor eye movements during real life tasks and thus can facilitate diagnosis of oculomotor disorders. 相似文献
1000.
Yanfeng Li Denghui Ji Shaopeng Liu Guide Tang Zhuangzhi Li Yuxi Yao Denglu Hou Minggang Zhu 《稀有金属(英文版)》2012,31(4):379-386
The fact that there are Mn2+ at the A sites in the ABO3 perovskite phase of manganites with the nominal composition La0.6-xNdxSr0.1MnO3 showed by detailed experimental study and theoretical calculations.The magnetic moments of these Mn2+ are antiparallel to those of the Mn ions at the B sites.The content of the Mn2+ increases as the average ionic radius,(rA),of the ions at A sites decreases,resulting in the experimentally observed phenomenon that the content of the Mn3O4 phase in the manganites decreases with decreasing 〈rA〉. 相似文献