DFT Study of Nitrogen-doped Graphene-based Carbon Materials as Metal-free Electrocatalysts for Oxygen Reduction Reaction: Insight into the Activity Sites

Fengna Guo, Aiping Fu, Wenbo Huai, Yue Yu, Yingqi Tang, Zonghua Wang

Abstract: A detailed theoretical study of nitrogen-doped graphene-based carbon materials as metal-free electrocatalysts for oxygen reduction reaction was carried out using DFT techniques to show insight into the catalytic activity site. The charge and spin density redistribution caused by different doping type of N (pyridine N, graphite N), doping number (1-2) and doping position (armchair edge, zigzag edge, center position, ortho-position, meta-position, and para-position) were employed to determine the active sites. The results show that the carbon atoms adjacent to the two pyridine nitrogen atoms exhibit the largest activity due to the presence of the dangling bonds. In order to confirm the conclusions derived from the cluster models, comparative periodic calculations were also performed. Through the calculation we found that the spin density distribution and electronic properties were strongly dependent on the N-doped topology structure, the cluster size, the doping type and position. The cluster C54H18 (P-N2) has the highest activity to promote the rate of oxygen reduction reaction. All the results obtained here deepen our understanding to the doped-N-based ORR catalysts and can be helpful for the rational design of such type of heteroatom-doped metal-free electrocatalysts.

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A Design for a Intelligent Drawer System

Dong Xie, Shilin Li, Qinqin Xiao, Shengxiong Wei, Yaxi LI, Jian Tong

Abstract: This design adopts single chip microcontroller (STM32F103) as the minimum system. The independent keystroke and single chip are the control module of the fingerprint. Fingerprint identification module and WIFI module constitute information acquisition module. The dc motor and the lock - clasp physical components constitute the electric locking module. Three LED lights constitute a status indicator module. The system is powered by a battery. The system has the advantages of simple structure, low production cost, high control accuracy and strong anti-interference ability.

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The Face Recognition Technology is Used in the Shanghai Disneyland

Yan Zhang, Dong Xie

Abstract: Face recognition is a new biometric identification technology that has emerged in recent years with the rapid progress of modern achievements such as computer technology, image processing technology and pattern recognition technology. The applications of this technology in urban security precautions have greatly improved the practical effects of security works. How to combine the social security of Disneyland and accelerate the application of urban surveillance is very meaningful.

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Application of Data Mining Technology in Tourism Image Creation

Zhenlei Yu

Abstract: With advances in computer technology, adopting data mining to analyze and process the assessment information of tourists in travel destinations has become an important way of doing research on tourism image. In this paper, taking Mount Tai scenic spot as an example, with the support of ROST Content Mining software, the author employs the method of content analysis to search for the tourists’ online assessment information, and probes into the tourists’ perception of the tourism image of Mount Tai, in the hope of providing a basis for the enhancement of tourism image.

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The construction of network model for industrial linkage of IT industry on the Campbell theory

Lili Wang, Wenwen Xiao, Chengwei Wang

Abstract: Industrial linkage is the objective existence in economy. Relational and spatial structure of multi-regional industrial linkage is not only a major factor in determining multi-regional disequilibrium strategy, but also an important source to obtain competitive advantages. This paper, by applying the Campbell theory, intends to construct network model for multi-regional industrial linkage of IT industry and conduct an empirical study using an inter-industry input-output table.

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Carbon modified lithium titanate using gelatin as carbon precursor and their application as anode for high performance lithium ions batteries

Tingting liang, Zhen Kong, Hongliang Li

Abstract: Spinel Li4Ti5O12 (LTO) is attractive anode material for lithium-ion batteries (LIBs) owing to their unique electrochemical properties. Therefore, Li4Ti5O12/C composite was successfully synthesized by hydrothermal method, using tetrabutyltitanate as titanium source, lithium hydroxide as lithium source and gelatin as carbon source. After the addition of gelatin, Li4Ti5O12 has better cycle performance and rate performance.

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