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Shijiazhuang, China

Hebei Normal University is a university in Hebei, China under the provincial government. Hebei Normal University is a provincial key university with a hundred-year history. The university originated from Shuntian School established in Beijing in 1902 and Beiyang Women Normal School established in Tianjin in 1906.Approved by Hebei provincial government, the former Hebei Teachers University, Hebei Teachers College, Hebei Education Institute established in 1952 and Hebei Vocational and Technological College merged into one in June 1996 and was named Hebei Normal University. Hebei Normal University is an early-established large-scale university in China. The names of many great revolutionary pioneers such as Deng Yingchao, Liu Qingyang, Guo Longzhen, Yang Xiufeng and Kang Shien are on the list of graduates. A group of famous scholars like Liang Suming, Zhang Shenfu and Tang Yongtong and others are on the list, too. Among the graduates are some academicians such as Yan Luguang and Hao Bolin and famous coaches and athletes who won championship in international games such as Xu Shaofa and Cai Zhenhua. Since New China was founded in 1949, Hebei Normal University has trained more than 200,000 people with professional skills. Wikipedia.

Li B.,Hebei Normal University
CMES - Computer Modeling in Engineering and Sciences | Year: 2014

In this paper, operational matrix method based on the generalized hat functions is introduced for the approximate solutions of linear and nonlinear fractional integro-differential equations. The fractional order generalized hat functions operational matrix of integration is also introduced. The linear and nonlinear fractional integro-differential equations are transformed into a system of algebraic equations. In addition, the method is presented with error analysis. Numerical examples are included to demonstrate the validity and applicability of the approach. Copyright © 2014 Tech Science Press.

Liu Z.,Cornell University | Zhang S.,Hebei Normal University | Wise F.W.,Cornell University
Optics Letters | Year: 2015

Experimental evidence of rogue-wave formation in a normal-dispersion ytterbium fiber laser is reported. Spectral filtering is a primary component of pulse-shaping in normal-dispersion lasers, and we find that the choice of filter dramatically influences the distribution of noise-pulse energies produced by these lasers. With an interference filter in the cavity, non-Gaussian distributions with pulses as large as 6 times the significant wave height are observed. These correspond to pulse energies as high as ∼50 nJ. To our knowledge, the results presented are not accounted for by existing theoretical models of rogue-wave formation. © 2015 Optical Society of America.

Geng L.,Hebei Normal University
Synthetic Metals | Year: 2010

Polypyrrole (PPy) and WO3 were prepared by chemical oxidation polymerization and emulsion method, respectively. PPy/WO3 hybrid materials with different PPy mass percent were prepared by mechanical mixing. WO3 and PPy/WO3 hybrids were characterized by XRD, SEM and HRTEM, and the sensitivity studies of PPy, WO3 and PPy/WO 3 to toxic gases NH3, H2S, NOx were also carried out. It was found that the particle size of WO3 was about 29 nm, and PPy/WO3 was about 50-100 nm. Gas sensitivity tests showed that when operated at 90 °C, PPy/WO3 hybrids had better reversibility to H2S than PPy higher sensitivity and selectivity to H2S than WO3. PPy/WO3 materials had short response-recovery time to H2S and their sensitivities had linear relationship with the concentration of H2S. The sensitive mechanism of PPy/WO3 materials to H2S may be the co-effect of proton doping process and the n-type semiconductor's effect. © 2010 Elsevier B.V.

Wu M.,Hebei Normal University | Ma T.,Dalian University of Technology
ChemSusChem | Year: 2012

Sun sans Pt: This Minireview summarizes the development of platinum-free catalysts for use as counter electrodes in dye-sensitized solar cells. These catalysts comprise various metals, carbon materials, conductive polymers, and inorganic materials (transition metal carbides, nitrides, oxides, sulfides, and phosphides). The research work reported so far highlights the importance of a proper match between counter electrode catalyst and redox couple. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Wu M.,Hebei Normal University | Ma T.,Dalian University of Technology | Ma T.,Kyushu Institute of Technology
Journal of Physical Chemistry C | Year: 2014

To realize long-term developments and practical application of the dye-sensitized solar cells (DSCs) requires a robust increase of the power conversion efficiency (PCE) and a significant decrease of the production cost. Fortunately, a new record PCE value of 12.3% was achieved by using cobalt-based redox couples combined with organic dye. Evidently, dye design is the key path to improve the PCE, while developing low cost counter electrode (CE) catalysts is one of the promising paths to reduce the production cost of DSCs by replacing the expensive Pt CE. In this article, we review the recent progress of CE catalysts involving Pt, carbon materials, inorganic materials, multiple compounds, polymers, and composites. We discuss the advantages and disadvantages of each catalyst and put forward ideas for designing new CE catalysts in future research for DSCs and other application fields. © 2014 American Chemical Society.

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