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Yan H.,Xinxiang University | Zhang L.,Xinxiang vocational and technical college
Energy Education Science and Technology Part A: Energy Science and Research | Year: 2014

Considering this requirement, this paper based on the Grey System Theory, using the Grey Model in a large bridges deformation monitoring information analyze and forecast, use the new model simulated and forecast the deformation monitoring of a large bridges. Comparing the traditional model with improved one, the result illustrates the reliability and advantage of improved GM (1,1) model. © Sila Science. All Rights Reserved. Source

Li W.,Xinxiang University | Wang X.,Xinxiang vocational and technical college | Sun L.,Zhengzhou University
Applied Mechanics and Materials | Year: 2011

The modes of a piece of disk spring and two piece of congruent disk spring are calculated by the finite element software ANSYS. Natural frequencies and vibration mode of every step are obtained. The results are analyzed. As a result, some useful references for design of disk spring are provided. © (2011) Trans Tech Publications, Switzerland. Source

Zhai C.,Henan University | Zhai C.,Shandong University | Cui F.,Xinxiang vocational and technical college | Liu X.,Henan University
Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy | Year: 2015

The molecular geometries, FT-IR and Raman spectra of 2-acetylpyridine were studied using Density functional theory (DFT-B3LYP) with the large basis sets. Theoretical calculations indicate the cis conformer of 2-acetylpyridine is most stable though this conformation was seldom found in the crystal structures of coordinated compounds. Based on the stable conformer, comprehensive assignments of the experimental bands were made. The observed and calculated positions are found to be in good agreement with an average deviation of <4 cm -1. The assignments provide valuable information for the fingerprint and identification of 2-acetylpyridine. © 2014 Elsevier B.V. All rights reserved. Source

Miao T.,Huazhong University of Science and Technology | Miao T.,Xinxiang vocational and technical college | Yu B.,Huazhong University of Science and Technology | Duan Y.,Southwest Petroleum University | Fang Q.,Southwest Petroleum University
International Journal of Heat and Mass Transfer | Year: 2015

Rocks with shear fractures or faults widely exist in nature such as oil/gas reservoirs, and hot dry rocks, etc. In this work, the fractal scaling law for length distribution of fractures and the relationship among the fractal dimension for fracture length distribution, fracture area porosity and the ratio of the maximum length to the minimum length of fractures are proposed. Then, a fractal model for permeability for fractured rocks is derived based on the fractal geometry theory and the famous cubic law for laminar flow in fractures. It is found that the analytical expression for permeability of fractured rocks is a function of the fractal dimension Df for fracture area, area porosity Φ, fracture density D, the maximum fracture length lmax, aperture a, the facture azimuth α and facture dip angle θ. Furthermore, a novel analytical expression for the fracture density is also proposed based on the fractal geometry theory for porous media. The validity of the fractal model is verified by comparing the model predictions with the available numerical simulations. © 2014 Elsevier Ltd. All rights reserved. Source

Wang K.,Henan Normal University | Miao T.,Xinxiang vocational and technical college | Liu Y.,Henan Normal University
Computational and Theoretical Chemistry | Year: 2011

All the possible rotamers of N,N-dimethylaminoethanol (DMAE) were fully optimized at the ab initio level using hybrid density functional B3LYP/aug-cc-pVDZ method. Twelve local minima for DMAE were found and their geometric parameters, dipole moments, intramolecular hydrogen bonds (HB) and relative energies of all conformers were determined. Their relative energies calculated at MP3 and MP4 (SDTQ) levels of theory further confirm that the gauche'-Gauche-gauche' (g'Gg') conformer having the intramolecular HB OH...N is the most stable. The vertical ionization energies of the conformers calculated with ab initio electron propagator theory in the P3/aug-cc-pVTZ approximation are in agreement with the experimental data from photoelectron spectroscopy. Combined with statistical mechanics principles, conformational distributions at various temperatures are computed and the temperature dependence of photoelectron spectra (PES) is interpreted. The intramolecular HB OH...N influences on the molecular electronic structures in the conformer g'Gg' was exhibited by Natural bond orbital (NBO) analyzes. © 2011. Source

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