Qingfan Zhang

China University of Geosciences

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i-10 index

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Co-Authors

Hansong Cheng

China University of Geosciences

Bo Han

Beijing Normal University

Dianli Hou

Ludong University

Mingyan Gao

Changchun University of Science and Technology

Robert C. Forrey

Pennsylvania State University

Wei An

National University of Defense Technology

Keke Huang

Jilin University

Xiaofeng Wu

Jilin University

Chenggang Zhou

China University of Geosciences

Bo Zhao

China University of Petroleum, Beijing

Cooperative Institutions

China University of Geosciences

Chinese Academy of Sciences

Air Products (United States)

National University of Singapore

Shandong University

Jilin University

University of Chinese Academy of Sciences

Changchun University of Science and Technology

State Key Laboratory of Inorganic Synthesis and Preparative Chemistry

Pennsylvania State University

Author Statistics

Papers

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Research Field

Concrete steel fiber content on the speed of sound and intensity

Sichuan Building Science (2013)

Qingfan Zhang

Through a variety of steel fiber reinforced concrete with the ratio test,using non-destructive measurement of the speed of sound,measured by conventional measuring the compressive strength of concrete,determine the velocity of Ultrasonic speed detector and the intensity of the relationship,the results are similar,the trend is consistent. Thus,detection of C40 concrete buildings during construction or operation arising in the course of the various internal problems,cracks and other damage,to make a more valuable reference. At the same time,and determine the volume of steel fiber content of the reasonable value,namely: C40 concrete steel fiber content should be controlled at 1. 0% to 1. 4%.

Intensity

Speed of Sound

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Clinical study on clomiphene-resistant polycystic ovarian syndrome with laparoscopic ovarian drilling combined with drugs

China Journal of Endoscopy (2014)

Qingfan Zhang

【Objective】To evaluate the efficacy of laparoscopic ovarian drilling(LOD) combined with Letrozole(LE) in the treatment of clomiphene-resistant polycystic ovary syndrome(PCOS).【Methods】72 patients with PCOS were randomly divided into study group and control group with 36 cases in each group, and the serum concentrations of LH, FSH, T and E2 were respectively compared before and after operation. Ovarian follicular development, pregnancy rate and abortion rate were observed and compared between the two groups. 【Results】There were significant decrease in level of LH and T after operations(P 0.05). The E2 level in study group after treatment was obviously lower than that in control group(P 0.05). The ovulation rate was significantly increased in study group compared with control group(P 0.05). 【Conclusion】LOD combined with Letrozole could significantly increase the ovulation rate and pregnancy rate in patients with CC-resistant PCOS.

Letrozole

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A novel image tamper localization and recovery algorithm based on watermarking technology

Optik (2013)

Junpeng Zhang Qingfan Zhang Hongli Lv

Peak signal-to-noise ratio

Sequence (biology)

SIGNAL (programming language)

10.1016/j.ijleo.2013.05.040

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Citations (33)

A feature-based watermarking algorithm resistant to copy attack

Junpeng Zhang Qingfan Zhang Shujuan Geng Mingyu Zhang

In this paper, a novel watermarking algorithm for colour image resistant to copy attack is presented. The method proposed is experimented in YUV colour space. The feature describing the original image uniquely is attained from the chroma component of the original colour image. After being scrambled by chaotic sequences, the feature is embedded into the luminance components of the host colour image and the watermark can be extracted blindly. We can detect copy attack by comparing the watermark extracted and the new feature of the watermarked image. The simulations show that the scheme is effectively robust against not only common image processing such as noise, JPEG compression, filtering, cropping, etc, but also copy attack.

Feature (linguistics)

10.1109/icinfa.2011.5949111

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Citations (2)

Investigation of the oil-seawater mixed flow under an electromagnetic field

Acta Oceanologica Sinica (2019)

Aiwu Peng Lingzhi Zhao Xiaoqiang Chen Qingfan Zhang Ciwen Sha

Lorentz force

Oil droplet

10.1007/s13131-019-1454-4

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Citations (2)

Highly active electrocatalyst of 3D Pd/reduced graphene oxide nanostructure for electro-oxidation of methanol and ethanol

Inorganic Chemistry Communications (2018)

Qingfan Zhang Xiaofeng Wu Mingyan Gao Haifang Qiu Jing Hu

Chronoamperometry

Nanomaterial-based catalyst

Direct-ethanol fuel cell

10.1016/j.inoche.2018.05.028

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Citations (11)

Hyperball fuzzy neural network based on clustering

Kongzhi yu juece (2011)

Hui Li Qingfan Zhang Peiyong Duan Ming Wang

A hyperball fuzzy neural network algorithm is proposed for modeling of uncertain, high-dimensional and complex nonlinear systems based on clustering. Firstly, an improved fuzzy cluster method(FCM) is given to determine the number of fuzzy rules. The one-dimensional membership functions are replaced by the multi-dimensional membership functions. Then, a one-pass algorithm is presented to calculate the centers and parameters of membership functions. The proposed approach can reduce the number of fuzzy rules and simplify the network calculation. Moreover, the fuzzy rules base can be modified online when the input-output data changes. The simulation results show the effectiveness of the proposed approach.

Defuzzification

Base (topology)

Fuzzy associative matrix

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Density Functional Theory Study of Water Dissociative Chemisorption on the Fe₃O₄(111) Surface

The Journal of Physical Chemistry C (2010)

Chenggang Zhou Qingfan Zhang Lei Chen Bo Han Gang Ni

Water dissociative chemisorption on the Feoct-tet1-terminated Fe3O4(111) surface was studied using periodic density functional theory (DFT) at both low and high water coverage. The active sites and adsorption patterns were identified, and the dissociation pathways and energetics were calculated. It was found that water can undergo dissociative chemisorption to form a surface hydroxyl group and a H atom with a favorable thermochemical energy and a moderate activation barrier at low coverage. This reaction can be readily catalyzed by water molecules around the active sites. We found that direct breakup of the hydroxyl group into H and O adatoms on the surface is energetically difficult and higher water coverage has an only modest effect on catalyzing the reaction. Our results are consistent with the kinetic and isotope exchange experiments.

Chemisorption

Kinetic isotope effect

10.1021/jp105040v

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Citations (59)

Density Functional Theory Study on the Role of Polyacetylene as a Promoter in Selective Hydrogenation of Styrene on a Pd Catalyst

The Journal of Physical Chemistry C (2017)

Shunxin Fei Bo Han Qingfan Zhang Ming Yang Hansong Cheng

Understanding mechanisms of catalyst–substrate interactions is of essential importance for the design and development of novel catalysts with superior performances. In the present density functional theory study, selective hydrogenation of styrene on a polyacetylene (PA)-supported Pd4 catalyst (Pd4/PA) was employed as a model system to address how catalyst–substrate interactions affect the charge state of Pd, which subsequently influences catalytic activity. It was found that the Pd cluster can be anchored strongly on the C═C bond of the polymer substrate through the π–d interaction, which further leads to charge rearrangement on the Pd4 cluster with the top two Pd atoms being more negatively charged. By comparing the calculated minimum energy profiles of styrene hydrogenation on surfaces of both pure Pd4 and Pd4/PA, the mechanism that dictates the catalytic process on Pd4/PA was identified. Charge analysis reveals that the enhanced catalytic activity of Pd4/PA is largely attributed to the negative charges on the two topmost Pd atoms, which facilitates both hydrogenation of styrene and desorption of the product. Nevertheless, PA hydrogenation to produce polyethylene (PE) was also found to be a potentially viable process with a moderate activation barrier of 0.43 eV, which may consequently lead to the formation of a PE-supported Pd4 catalytic system. As a consequence, the absence of π orbitals of the PE substrate may significantly reduce the electronic interaction between Pd4 and PE, which ultimately leads to the catalytic performance similar to the activity on the pure Pd4 cluster.

Polyacetylene

10.1021/acs.jpcc.6b10290

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Citations (8)

Dsp based implementation of space vector pulsewidth modulation in the overmodulation range

International Conference on Electric Information and Control Engineering (2011)

Weitao Kong Qingfan Zhang Chenghui Zhang

The principle of space vector pulsewidth overmodulation strategies is developed from conventional space vector modulation scheme and the corresponding algorithm based on the representation of the switching vectors in the complex plane is proposed. The overmodulation range is divided into two modes depending on the modulation index, and the two modes are distinguished by the holding angle at the vertices of the hexagon. The method is described and analyzed, and the experimental results are presented in overmodulation mode I. The solution increases the output voltage of inverter in a continuously controllable fashion.

Overmodulation

Modulation (music)

Modulation index

Space vector modulation

10.1109/iceice.2011.5777931

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Citations (1)