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Chen D.,Henan University | Cao Y.,Zhumadian Vocational and Technical College | Shi L.,Henan University | He J.,Henan University
Huaxue Fanying Gongcheng Yu Gongyi/Chemical Reaction Engineering and Technology | Year: 2012

A catalyst, Ti/W-MCM-41 was developed through MCM-41 zeolite with titanium-tungsten bimetal modification in situ. The acidity of the zeolite was the largest when n(Si): n(Ti) is 30: 1, n(Si): n(W) is 25: 1, calcinating at 500°C for 4 h. It was characterized by FTIR techniques and employed as a esterifying catalyst for synthesis of amyl propionate. The effects of various parameters such as preparative conditions of the catalyst(calcination temperature and calcination time of catalyst), catalyst dosage, mole ratio of n-pentanol to propionic acid, reaction time and reusability of the catalyst on esterification rate were investigated. The optimized conditions of synthesizing amyl propionate were: propionic acid 0.2 mol, mole ratio of n-pentanol to propionic acid 1.4, mass fraction of catalyst in all of reaction system 1.25%, reaction time 3.5 h, esterification rate could reach 97.6% The esterification rate kept above 79% after being reused seven times. Source

Yang G.,Henan University | Cao Y.,Zhumadian Vocational and Technical College | Shi L.,Henan University | He J.,Henan University | Chen D.,Henan University
Shiyou Huagong/Petrochemical Technology | Year: 2011

A novel silica supported oxide catalyst Ga 2O 3/SiO 2 for esterification was prepared and characterized by means of FTIR. The catalyst was used in esterification of n-octanol and n-butyric acid to octyl butyrate. The effects of the catalyst preparation conditions (Ga 2O 3 loading and the catalyst calcination temperature), catalyst dosage, mole ratio of n-octanol to n-butyric acid, reaction time and the catalyst reuse on the esterification rate were investigated. These results indicated that under the suitable conditions of Ga 2O 3 loading(w) 20%, calcination temperature 500°C and calcination time 2 h for the catalyst preparation, and n-butyric acid 0.2 mol, mole ratio of n-octanol to n-butyric acid 1.8, the catalyst mass fraction in the reaction system 1.03%, water entrainer cyclohexane 10 mL and reaction time 120 min for the esterification reaction, the esterification rate could reach 96.5%. The catalyst exhibited high activity up to 94.3% after being reused three times. Furthermore, its thermal stability obviously exceeded the esterification catalysts SO 4 2-/SiO 2 and SO 4 2-/ SiO 2-Ga 2O 3. Source

Wang Q.,Beijing Union University | Wang Z.,Zhumadian Vocational and Technical College
Journal of Theoretical and Applied Information Technology | Year: 2013

Mesh networks have been applied to build large scale multicomputer systems and Network-on-Chips (NoCs) extensively. Mesh networks perform poorly in tolerating faults in the view of worst-case analysis, so it is practically important for multicomputer systems and NoCs manufactures to determine that how much success probability to construct a fault-free path between two non-faulty nodes for the mesh network when the node failure probability and the network size are given. In this paper, we mainly focus on fault-tolerant routing algorithm on mesh networks from probabilistic view, and provide a probabilistic method for studying routing algorithm. We propose two simple and novel routing algorithms based on the concept of k-submesh. We apply probabilistic analysis on the fault tolerance of our routing algorithms. Suppose that each node fails independently with given probability, we can derive the probability that our routing algorithms successfully return a fault-free routing path. For example, we formally prove that our routing algorithms succeed in finding a fault-free routing path with success probability at least 99% for a mesh network of up to twenty-thousand nodes as long as the node failure probability is bounded by 1.87%. Our routing algorithms run in liner time. Simulation results show that the length of the routing paths constructed by our algorithms is very close to the optimal length. On the other hand, the results also show that the multicomputer systems and NoCs based on mesh networks are quite reliable and trustable in theory and practice. © 2005 - 2013 JATIT & LLS. All rights reserved. Source

Dong X.,Jianghai Polytechnic College | Wang Z.,Zhumadian Vocational and Technical College | Shi Y.,Yangzhou Polytechnic Institute
Journal of Theoretical and Applied Information Technology | Year: 2013

E-Learning emerges as the times require under the network environment. It is a new teaching and learning mode, this paper analyzes the meaning of E-Learning, teaching mode, as well as the traditional Chinese education influence. Service Software Bus (SSB) is a service-oriented software bus. Based on theory basis of existing general software and combing with loosely coupled service-oriented architecture technology based on business standards, a kind of SSB is proposed and designed. Such kind of service-oriented software bus architecture is then applied into E-Learning teaching platform to conduct overall design of E-Learning teaching platform. Detail design of each functional layer of the teaching platform is also given. © 2005 - 2013 JATIT & LLS. All rights reserved. Source

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