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Computational Economics - The study aims to analyze and forecast Internet financial risks based on the model based on deep learning and the Back Propagation Neural Network (BPNN). First, the theory... 相似文献
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A Novel and Facile Route to Synthesize Atomic‐Layered MoS2 Film for Large‐Area Electronics 下载免费PDF全文
Stephen Boandoh Soo Ho Choi Ji‐Hoon Park So Young Park Seungho Bang Mun Seok Jeong Joo Song Lee Hyeong Jin Kim Woochul Yang Jae‐Young Choi Soo Min Kim Ki Kang Kim 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(39)
High‐quality and large‐area molybdenum disulfide (MoS2) thin film is highly desirable for applications in large‐area electronics. However, there remains a challenge in attaining MoS2 film of reasonable crystallinity due to the absence of appropriate choice and control of precursors, as well as choice of suitable growth substrates. Herein, a novel and facile route is reported for synthesizing few‐layered MoS2 film with new precursors via chemical vapor deposition. Prior to growth, an aqueous solution of sodium molybdate as the molybdenum precursor is spun onto the growth substrate and dimethyl disulfide as the liquid sulfur precursor is supplied with a bubbling system during growth. To supplement the limiting effect of Mo (sodium molybdate), a supplementary Mo is supplied by dissolving molybdenum hexacarbonyl (Mo(CO)6) in the liquid sulfur precursor delivered by the bubbler. By precisely controlling the amounts of precursors and hydrogen flow, full coverage of MoS2 film is readily achievable in 20 min. Large‐area MoS2 field effect transistors (FETs) fabricated with a conventional photolithography have a carrier mobility as high as 18.9 cm2 V?1 s?1, which is the highest reported for bottom‐gated MoS2‐FETs fabricated via photolithography with an on/off ratio of ≈105 at room temperature. 相似文献
164.
DNA Imaging: DNA Binding Peptide Directed Synthesis of Continuous DNA Nanowires for Analysis of Large DNA Molecules by Scanning Electron Microscope (Small 2/2017) 下载免费PDF全文
165.
Ren Wuyang Li Handong Gao Lei Li Yong Zhang Zhongyang Long Chengjia Ji Haining Niu Xiaobin Lin Yuan Wang Zhiming 《Nano Research》2017,10(1):247-254
Nano Research - Thermal transport in superlattices is governed by various phonon-scattering processes. For extracting the phonon-scattering contribution of hetero-interfaces in chalcogenide... 相似文献
166.
Qiyi Fang Zhepeng Zhang Qingqing Ji Siya Zhu Yue Gong Yu Zhang Jianping Shi Xiebo Zhou Lin Gu Qian Wang Yanfeng Zhang 《Nano Research》2017,10(8):2761-2771
Molybdenum ditelluride (MoTe2),which is an important transition-metal dichalcogenide,has attracted considerable interest owing to its unique properties,such as its small bandgap and large Seebeck coefficient.However,the batch production of monolayer MoTe2 has been rarely reported.In this study,we demonstrate the synthesis of large-domain (edge length exceeding 30 μm),monolayer MoTe2 from chemical vapor deposition-grown monolayer MoS2 using a chalcogen atom-exchange synthesis route.An in-depth investigation of the tellurization process reveals that the substitution of S atoms by Te is prevalently initiated at the edges and grain boundaries of the monolayer MoS2,which differs from the homogeneous selenization of MoS2 flakes with the formation of alloyed Mo-S-Se hybrids.Moreover,we detect a large compressive strain (approximately-10%) in the transformed MoTe2 lattice,which possibly drives the phase transition from 2H to 1T'at the reaction temperature of 500 ℃.This phase change is substantiated by experimental facts and first-principles calculations.This work introduces a novel route for the templated synthesis of two-dimensional layered materials through atom substitutional chemistry and provides a new pathway for engineering the strain and thus the intriguing physics and chemistry. 相似文献
167.
Ji Chan Park Shin Wook Kang Jeong-Chul Kim Jae In Kwon Sanha Jang Geun Bae Rhim Mijong Kim Dong Hyun Chun Ho-Tae Lee Heon Jung Hyunjoon Song Jung-II Yang 《Nano Research》2017,(3):1044-1055
A cobalt-silica hybrid nanocatalyst bearing small cobalt particles of diameter ~5 nm was prepared through a hydrothermal reaction and hydrogen reduction.The resulting material showed very high CO conversion (>82%) and high hydrocarbon productivity (~1.0 gHc·g-1cat,·h-11) with high activity (~8.5 x 10-5 molco·g-1Co·S-1) in the Fischer-Tropsch synthesis reaction. 相似文献
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