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Beijing, China

Capital Normal University is a university in Beijing, China. It is covered by Project 211, a policy to renew and modernize educational facilities in the People's Republic of China. Wikipedia.

Wang G.,Capital Normal University
Physical Chemistry Chemical Physics | Year: 2011

Armchair graphene nanoribbons and their derived structures containing Stone-Wales defects are investigated using a self-consistent field crystal orbital method based on density functional theory. The investigation indicates that both the nanoribbons and the defective structures are semiconductors. A low concentration of middle Stone-Wales defects generally increases the carrier mobility, calculated using deformation potential theory, while edge Stone-Wales defects decrease it. The largest increment of the carrier mobility is as high as 170%, which is explained by the lighter carrier effective mass with crystal orbital analysis. © the Owner Societies 2011. Source

Ye N.S.,Capital Normal University
Critical reviews in food science and nutrition | Year: 2012

Chemical compositions in tea leaves are influenced by their growing surrounding, and the content of these components are related to the quality of teas. The determination of the concentration of chemical composition in teas will predict the ranking of teas and indicate the geographical origins. This overview concerns an investigation of analytical methods that are being used for the determination of the geographical origin of tea. The analytical approaches have been subdivided into three groups: spectroscopic techniques, chromatographic techniques, and other techniques. The advantages, drawbacks, and reported applications concerning geographical authenticity are discussed. Source

Wang G.,Capital Normal University
Chemical Physics Letters | Year: 2012

Armchair graphene nanoribbons as well as those with hydrogen-passivated or hydrogen-saturated edges are investigated by using self-consistent field crystal orbital method based on density functional theory. The investigation indicates that different band gap alterations and polarity behaviors with respect to the width exist in these nanoribbons. The carrier mobilities obtained under deformation potential theory decrease with the addition of edge-hydrogens, but are still in the same order. However, edge-hydrogen passivation could be helpful to reduce edge disorder and degradation of carrier mobilities. © 2012 Elsevier B.V. All rights reserved. Source

Jin Y.,Capital Normal University
Molecular and Cellular Biochemistry | Year: 2011

3,3′-Diindolylmethane (DIM) is a potential cancer preventive phytochemical derived from Brassica vegetables. The effects of DIM on cell-cycle regulation in both estrogen-dependent MCF-7 and estrogen receptor negative p53 mutant MDA-MB-468 human breast cancer cells were assessed in this study. DIM inhibited the breast cancer cell growth in vitro and in vivo, and caused cellcycle arrest by down-regulating protein levels of cell-cycle related kinases CDK1, CDK2, CDK4, and CDK6, as well as Cyclin B1 and Cdc25A. Meanwhile, it was revealed that Ser124 phosphorylation of Cdc25A is primarily responsible for the DIM-induced Cdc25A degradation. Furthermore, treatment of MCF-7 cells with DIM increased miR-21 expression and down-regulated Cdc25A, resulting in an inhibition of breast cancer cell proliferation. These observations collectively suggest that by differentially modulating cellular signaling pathways DIM is able to arrest the cell-cycle progression of human breast cancer cells. Source

Capital Normal University, Chongqing Normal University and Beijing Waitenksin Advanced Technology Co. | Date: 2011-06-14

A method for measuring thickness or defect depth by pulsed infrared thermal wave technology is described. The method includes heating a measured object by pulsed heating devices, and at the same time, obtaining a thermal image sequence on the surface of the measured object by an infrared thermography device, and storing the thermal image sequence in a general-purpose memory. The method also includes multiplying a temperature-time curve at every point of the thermal image sequence by a corresponding time, thereby obtaining a new curve. The method also includes calculating a first-order differential and obtaining a peak time thereof. The method also includes use of one or more formulas to thereby determine the thickness or the defect depth of the measured object.

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