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1.
Science China Chemistry - 相似文献
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以过渡金属为催化衬底的化学气相沉积法(Chemical Vapor Deposition,CVD)已经可以制备与机械剥离样品相媲美的石墨烯,是实现石墨烯工业应用的关键技术之一。原子尺度理论研究能够帮助我们深刻理解石墨烯生长机理,为实验现象提供合理的解释,并有可能成为将来实验设计的理论指导。本文从理论计算的角度,总结了各种金属衬底在石墨烯CVD生长过程中的各种作用与相应的机理,包括在催化碳源裂解、降低石墨烯成核密度等,催化加快石墨烯快速生长,修复石墨烯生长过程中产生的缺陷,控制外延生长石墨烯的晶格取向,以及在降温过程中石墨烯褶皱与金属表面台阶束的形成过程等。在本文最后,我们对当前石墨烯生长领域中亟需解决的理论问题进行了深入探讨与展望。 相似文献
3.
Xu Yifan Zhang Hehe Ding Tangjing Tian Ruiqi Sun Dongmei Wang Ming-Sheng Zhou Xiaosi 《中国科学:化学(英文版)》2022,65(9):1807-1816
Science China Chemistry - Due to their enormous potential for large-scale energy storage, rechargeable potassium-ion batteries have been widely researched and developed. However, the drastic volume... 相似文献
4.
CdS/Si nanofilm heterojunctions based on amorphous silicon films:Fabrication,structures,and electrical properties 下载免费PDF全文
Shortening the distance between the depletion region and the electrodes to reduce the trapped probability of carriers is a useful approach for improving the performance of heterojunction.The CdS/Si nanofilm heterojunctions are fabricated by using the radio frequency magnetron sputtering method to deposit the amorphous silicon nanofilms and Cd S nanofilms on the ITO glass in turn.The relation of current density to applied voltage(I-V)shows the obvious rectification effect.From the analysis of the double logarithm I-V curve it follows that below~2.73 V the electron behaviors obey the Ohmic mechanism and above~2.73 V the electron behaviors conform to the space charge limited current(SCLC)mechanism.In the SCLC region part of the traps between the Fermi level and conduction band are occupied,and with the increase of voltage most of the traps are occupied.It is believed that Cd S/Si nanofilm heterojunction is a potential candidate in the field of nano electronic and optoelectronic devices by optimizing its fabricating procedure. 相似文献
5.
Potential Analysis - The purpose of this paper is to provide necessary and sufficient conditions of the boundedness for singular integrals on the local Hardy space and its dual. Particularly the... 相似文献
6.
A complete manifold is said to be nonparabolic if it does admit a positive Green’s function. To ?nd a sharp geometric criterion for the parabolicity/nonparbolicity is an attractive question inside the function theory on Riemannian manifolds. This paper devotes to proving a criterion for nonparabolicity of a complete manifold weakened by the Ricci curvature. For this purpose, we shall apply the new Laplacian comparison theorem established by the ?rst author to show the existence of a non-constant bounded subharmonic function. 相似文献
7.
Liu Jinjie Yang Xinmin Zeng Shengda Zhao Yong 《Journal of Optimization Theory and Applications》2022,193(1):877-909
Journal of Optimization Theory and Applications - In this paper, we introduce and investigate a new kind of coupled systems, called coupled variational inequalities, which consist of two elliptic... 相似文献
8.
Ding Q. Yao M. Wu Sh. Zeng M. Xue N. Wu D. Xu J. 《Journal of Applied Spectroscopy》2022,89(4):712-718
Journal of Applied Spectroscopy - Based on partial least squares (PLS) analysis, the effects of different smoothing points and different preprocessing methods on the accuracy and precision of the... 相似文献
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10.
This paper studies synchronization of all nodes in a fractional-order complex dynamic network. An adaptive control strategy for synchronizing a dynamic network is proposed. Based on the Lyapunov stability theory, this paper shows that tracking errors of all nodes in a fractional-order complex network converge to zero. This simple yet practical scheme can be used in many networks such as small-world networks and scale-free networks. Unlike the existing methods which assume the coupling configuration among the nodes of the network with diffusivity, symmetry, balance, or irreducibility, in this case, these assumptions are unnecessary, and the proposed adaptive strategy is more feasible. Two examples are presented to illustrate effectiveness of the proposed method. 相似文献