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Feng J.,Xidian University | Zhang Y.,Intrusion | Wang H.,Huaibei Coal Normal College
IEICE Transactions on Information and Systems | Year: 2010

The security of P2P networks depends on building trust management among peers. However, current trust management models focus on preventing untrustworthy resources from spreading by malicious providers, but have few effects on reducing denial-of-service attacks of malicious consumers and free riding of selfish peers. Pointing to these problems, a bi-evaluation* * * trust management model, called BiTrust, is proposed. In this model, the trustworthiness of a peer is divided into service and request trustworthiness. Service trustworthiness shows the resources reliability of providers, and request trustworthiness is used to deal with requests from consumers, which can keep away malicious consumers and encourage selfish peers to share resources. A generic method for evaluating service and request trustworthiness is described. Furthermore, the implementation strategies of the model are also depicted in this paper. The following analysis and simulation show that BiTrust is more effective on enhancing high-quality resources sharing among peers and more advanced in successful exchanges rate. Copyright © 2010 The Institute of Electronics, Information and Communication Engineers.


Shifu C.,Huaibei Coal Normal College | Wei L.,Huaibei Coal Normal College | Sujuan Z.,Huaibei Coal Normal College | Yinghao C.,Ocean University of China
Journal of Sol-Gel Science and Technology | Year: 2010

Co-TiO2 photocatalyst was prepared by a sol- gel method using Co(NO3)26H2O and tetrabutyl titanate [Ti(OC4H9)4] as raw materials, and Co-TiO 2/TiO2 photocatalyst was synthesized by mixing the Co-TiO2 sol with TiO2 sol. The Co-TiO2/TiO2 was characterized by X-ray powder diffraction, UV-Vis diffuse reflection spectrum, scanning electron microscopy, transmission electron microscopy, fluorescence spectra and X-ray photoelectron spectroscopy. The photocatalytic activity of the photocatalyst was evaluated by photocatalytic reduction of Cr2O 7 2- and photocatalytic oxidation of methyl orange under UV irradiation. The results showed that, for the photocatalytic reduction of Cr2O7 2-, the optimum percentage of Codoped for the Co-TiO2 was 0.5% (mole ratio of Co/Ti), and the optimum percentage of Co-TiO2 for the Co-TiO2/TiO2 was 2.0% (mole ratio of Co-TiO2/TiO2). The photocatalytic reduction activities of the Co-TiO2/TiO2 and Co-TiO 2 are much higher than that of TiO2. However, the photocatalytic oxidation activities of the Co-TiO2/TiO2 and Co- TiO2 are much lower than that of TiO2. Effects of heat treatment on the photocatalytic activities of the Co-TiO2/ TiO2 and Co-TiO2 were investigated. The mechanisms of influence on the photocatalytic activity were also discussed. ©Springer Science+Business Media, LLC 2010.


Wei L.,Huaibei Coal Normal College | Shifu C.,Huaibei Coal Normal College | Sujuan Z.,Huaibei Coal Normal College | Wei Z.,Huaibei Coal Normal College | And 2 more authors.
Journal of Nanoparticle Research | Year: 2010

In this article, the p-type CuBi2O4 powder was prepared by the solid-state reaction method. The p-n heterojunction photocatalyst p-CuBi2O4/n-TiO2was prepared by ball milling. The photocatalyst was characterized by X-ray powder diffraction (XRD), UV-Vis diffuse reflectance spectroscopy, scanning electron microscopy (SEM), and photoluminescence emission spectra. The photocatalytic activity of the photocatalyst was evaluated by photocatalytic reduction of Cr 2O72-and photocatalytic oxidation of methyl orange (MO). The results showed that the photocatalytic activity of the p-n heterojunction photocatalystp-CuBi2O4/n-TiO2 was much higher than that of TiO2 and the mixture of p-CuBi2 O-4-n-TiO2 without ball milling under visible and UV light irradiation. The optimal percentage of doped p-CuBi 2O4is 20 wt%. Compared with pure TiO2, the photoabsorption wavelength range of the photocatalyst is extended greatly toward visible light and improves the utilization of the total spectrum. The effect of ball milling time on thephotocatalytic activity of the photocatalyst was also investigated. The optimum ball milling time is 6 h. The mechanisms of influence of p-CuBi2O4 on the photocatalytic activity of p-CuBi 2O4/n-TiO2 were also discussed by the p-n junction principle and the valance band theory.


Huang Y.,Huaibei Coal Normal College | Huang Y.,Huaibei Occupational Disease Prevention and Cure Hospital | Yan J.,Huaibei Occupational Disease Prevention and Cure Hospital | Liu B.,Huaibei Coal Normal College | And 4 more authors.
Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy | Year: 2010

The interaction between prulifloxacin, a kind of new oral taking antibiotic and pepsin, a kind of enzyme in the stomach has been investigated in vitro under a simulated physiological condition by different spectroscopic methods. The intrinsic fluorescence of pepsin was strongly quenched by prulifloxacin. This effect was rationalized in terms of a static quenching procedure. The binding parameters have been evaluated by fluorescence quenching methods. The negative value of ΔG0 reveals that the binding process is a spontaneous process. The binding distance R between donor (pepsin) and acceptor (prulifloxacin) was obtained according to the Förster's resonance energy transfer theory and found to be 0.95 nm. The results obtained herein will be of biological significance in pharmacology and clinical medicine. Crown Copyright © 2010.


Qiu G.,Xidian University | Wang H.,Huaibei Coal Normal College | Xiao H.,Xidian University | Xiao G.-Z.,Xidian University
Xi'an Dianzi Keji Daxue Xuebao/Journal of Xidian University | Year: 2010

Forward-secure blind signature schemes can provide important security guarantees: all secret keys and digital signatures before current key exposure will still be secure. We make a Security analysis of the recent two new forward-secure blind signature schemes respectively proposed by Hui-Feng Huang et al and Yali Liu et al. These schemes are totally broken by cryptanalysis on the key structure or hardness problem. It is proved that they are not forward-secure.


Wei L.,Huaibei Coal Normal College | Shifu C.,Huaibei Coal Normal College | Huaye Z.,Huaibei Coal Normal College | Xiaoling Y.,Huaibei Coal Normal College
Journal of Experimental Nanoscience | Year: 2011

In this article, the Bi2WO6 powder was prepared by the solid-state reaction method. The p-n heterojunction photocatalyst CuBi2O4/Bi2WO6 was prepared by ball milling through doping CuBi2O4 into Bi2WO6. The photocatalyst was characterised by X-ray powder diffraction (XRD), UV-Vis diffuse reflectance spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and photoluminescence emission spectra. The results showed that the photocatalytic activity of CuBi2O4/Bi2WO6 was much higher than that of Bi2WO6 on the photocatalytic reduction of Cr2O2-7. However, the photocatalytic activity of the photocatalyst was much lower than that of Bi2WO6 on the photocatalytic oxidation of methylene blue (MB). For the photocatalytic reduction of Cr2O2-7, the optimum amount of doped CuBi2O4 is 1.0 wt%. Compared with the pure Bi2WO6, the photoabsorption wavelength range of the photocatalyst is extended greatly towards visible light and improves the utilisation of the total spectrum. The effect of the ball milling time on the photocatalytic activity of the photocatalyst was also investigated. The optimum ball milling time is 6 h. The mechanisms of the increase in the photocatalytic activity were discussed by the p-n junction principle and the valance band theory. © 2011 Taylor & Francis.


Shifu C.,Huaibei Coal Normal College | Xiaoling Y.,Huaibei Coal Normal College | Huaye Z.,Huaibei Coal Normal College | Wei L.,Huaibei Coal Normal College
Journal of the Electrochemical Society | Year: 2010

Fe- TiO2 photocatalyst was prepared by a sol-gel method using tetrabutyl titanate [Ti (OC4 H9) 4] as the titanium precursor. The composite photocatalyst Fe- TiO2 / TiO 2 was prepared by the ballmilling method. The structure and properties of the samples were characterized by X-ray powder diffraction, UV/visible diffuse reflectance spectroscopy, X-ray photoelectron spectroscopy, and photoluminescence (PL) emission spectroscopy. The terephthalic acid was used as a probe molecule to detect the generation of hydroxyl radicals (OH) on the surface of UV-illuminated photocatalyst by a PL technique. The results showed that doping Fe3+ into TiO2 is more beneficial toward the photocatalytic reduction rather than oxidation with the optimum amount level of 0.05% (Fe/Ti molar ratio). After coupling between Fe- TiO2 and TiO2, both the photo-oxidation and photoreduction activities of the sample are enhanced. Among the composite Fe- TiO2 / TiO2 samples, the Fe- TiO2 (5.0 wt %)/ TiO2 sample exhibits the best photocatalytic activity. It is proposed that the photo-oxidation and photoreduction activities are promoted by coupling Fe- TiO2 and TiO2 as a homojunction where the photoexcited holes and electrons are separated effectively. © 2010 The Electrochemical Society.


Chen S.,Huaibei Coal Normal College | Zhang H.,Huaibei Coal Normal College | Yu X.,Huaibei Coal Normal College | Liu W.,Huaibei Coal Normal College
Chinese Journal of Chemistry | Year: 2010

The feasibility of photocatalytic reduction of nitrobenzene using titanium dioxide powder as photocatalyst, underthe protection of nitrogen and presence of hole scavenger conditions, was studied. Effects of the illuminationtime, amount of catalyst and sorts of solvent on the photocatalytic reduction of nitrobenzene were investigated, respectively.The results showed that, for the photocatalytic reduction of nitrobenzene, aniline was the main product.When the illumination time was 6 h, 8.15×10-4 mol/L of nitrobenzene could be photocatalytically reduced completely,with the yield of aniline being 88.5%. The optimum amount of TiO2 used was 4.0 g/L, the optimum initialpH value of reaction solution was 4.0 and the best solvent was methanol. The kinetics and mechanisms of thephotocatalytic reduction of nitrobenzene were also discussed. © 2010 SIOC, CAS, Shanghai, & WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Huang Y.,Huaibei Coal Normal College | Liu B.,Huaibei Coal Normal College | Yu Z.,Huaibei Coal Normal College | Zi Y.,Huaibei Coal Normal College
Journal of Luminescence | Year: 2010

Prulifloxacin is a kind of new oral taking antibiotic of fluoroquinolone. Conjugation reaction of prulifloxacin with trypsin in Britton-Robinson buffer solution of pH 7.96 was analyzed by UV-vis spectrophotometry and fluorescence spectrometry. The intrinsic fluorescence of trypsin was strongly quenched by prulifloxacin. This effect was rationalized in terms of a static quenching procedure. The binding parameters have been evaluated by fluorescence quenching methods. Negative values ΔG0 for the formation of prulifloxacin-trypsin complex implied that both hydrogen bonds and hydrophobic interactions might play a significant role in prulifloxacin binding to trypsin. The binding distance deduced from the efficiency of energy transfer was 0.84 nm for prulifloxacin-trypsin. Furthermore, association constants and binding mechanism were successfully derived from the fluorescence spectra. UV-vis detections supported a change in the secondary structure of proteins caused by the interaction of prulifloxacin with trypsin. © 2009 Elsevier B.V. All rights reserved.


Hu W.,Huaibei Coal Normal College | Sun D.,Huaibei Coal Normal College | Ma W.,Huaibei Coal Normal College
Electroanalysis | Year: 2010

In this paper, a silver doped poly(L-valine) (Ag-PLV) modified glassy carbon electrode (GCE) was fabricated through electrochemical immobilization and was used to electrochemically detect uric acid (UA), dopamine (DA) and ascorbic acid (AA) by linear sweep voltammetry. In pH 4.0 PBS, at a scan rate of 100 mV/s, the modified electrode gave three separated oxidation peaks at 591 mV, 399 mV and 161 mV for UA, DA and AA, respectively. The peak potential differences were 238 mVand 192 mV. The electrochemical behaviors of them at the modified electrode were explored in detail with cyclic voltammetry. Under the optimum conditions, the linear ranges were 3.0×10-7 to 1.0×10-5 M for UA, 5.0×10-7 to 1.0×10-5 M for DA and 1.0×10-5 to 1.0×10-3 M for AA, respectively. The method was successfully applied for simultaneous determination of UA, DA and AA in human urine samples. © 2010 Wiley-VCH Verlag GmbH&Co. KGaA, Weinheim.

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