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Hengyang, China

Chen Q.-C.,Hengyang Normal University
Chinese Physics B | Year: 2014

By using semiclassical theory combined with multiple-scale method, we analytically study the linear absorption and the nonlinear dynamical properties in a lifetime broadened L-type three-level self-assembled quantum dots. It is found that this system can exhibit the transparency, and the width of the transparency window becomes wider with the increase of control light field. Interestingly, a weak probe light beam can form spatial weak-light dark solitons. When it propagates along the axial direction, the soliton will transform into a steady spatial weak-light ring dark soltion. In addition, the stability of two-dimensional spatial optical solitons is testified numerically. © 2014 Chinese Physical Society and IOP Publishing Ltd. Source

Liu M.,Hengyang Normal University | Luo C.,East China Normal University | Peng H.,East China Normal University
Talanta | Year: 2012

A polythiophene functionalized with methylene blue (PMT-MB) was synthesized and used as an indicator for electrochemical oligonucleotides (ODNs) hybridization detection. After hybridization with complementary ODNs, the current signal of PMT-MB increased, which illustrated that PMT-MB can effectively recognize complementary ODN targets as an indicator. Compared to MB, PMT-MB showed much better resistance to the concentration change of buffer solution. In all buffer solutions tested, the hybridization always resulted in the increased current signal of PMT-MB due to the electrostatic interaction. While, when MB was used as an indicator, the inconsistent current response was obtained after the hybridization. When high concentration of buffer solution was used for accumulation, the hybridization resulted in the decreased current signal, while at the low concentrations, the current signal increased. The interaction between PMT-MB and dsODNs was also studied by UV-vis spectroscopy. © 2011 Elsevier B.V. All rights reserved. Source

Jiang H.,Hengyang Normal University
Advances in Information Sciences and Service Sciences | Year: 2012

To aim the problem of document image segmentation, we propose a topic model based method to segment the document images into several areas, such as text, background, tables and figures. In the past, the segmentation of document images focused on threshold based method or supervised learning method. In our work, we firstly build a codebook by using PCA and K-means which only need an unsupervised learning method. Then, the document images are coded using codebook and the probability of each code is calculated using LDA based method, which is followed by a Markov random field, based labeling procedure. The advantage of proposed method include: unsupervised learning phase more reliable probability from LDA and smoothed segmentation results from MRF. Source

Yang Z.,Hengyang Normal University
Zeitschrift fur Angewandte Mathematik und Physik | Year: 2015

In this paper, we consider initial-boundary value problem of Euler–Bernoulli viscoelastic equation with a delay term in the internal feedbacks. Namely, we study the following equation (Formula presented.) together with some suitable initial data and boundary conditions in Ω×(0,+∞). For arbitrary real numbers μ1 and μ2, we prove that the above-mentioned model has a unique global solution under suitable assumptions on the relaxation function g. Moreover, under some restrictions on μ1 and μ2, exponential decay results of the energy for the concerned problem are obtained via an appropriate Lyapunov function. © 2014, Springer Basel. Source

Xu L.,South China Agricultural University | Xu Z.-F.,Hengyang Normal University
Journal of Polymer Research | Year: 2012

Molecularly imprinted polymers on the surface of multiwalled carbon nanotubes (MWNTs) have been developed for selective recognition for Ribavirin. The composites (MWNTs/MIPs) were prepared by using Ribavirin as the template molecule, acrylamide (AAM) as the functional monomer, N, N- methylenebisacrylamide (NNMBA) as the cross-linker. MWNTs/MIPs obtained were characterized by fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and thermogravimetric analysis (TGA). The properties such as adsorption dynamics, special binding, and the selective recognition ability were evaluated. The adsorption equilibrium was arrived in about 4 h which indicated that the adsorption kinetic was comparatively fast. The results of binding and selectivity experiments showed that the MWNTs/MIPs could bind the template molecule selectively in aqueous media. © Springer Science+Business Media B.V. 2012. Source

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