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On the core of the fractional Fourier transform and its role in composing complex fractional Fourier transformations and Fresnel transformations

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Frontiers of physics 2015年第1期10卷 1-6页

作者： Hong-Yi Fan jun-hua chen Department of Physics Ningbo University Ningbo 315211 China Department of Material Science and Engineering University of Science and Technology of China Hefei 230026 China

By a quantum mechanical analysis of the additive rule Fa [Fβ[f]] = Fα＋β[f], which the fractional Fourier transformation （FrFT） Fα [f] should satisfy, we reveal that the position-momentum mutual- transformation operator is the core element for constructing the integration kernel of FrFT. Based on this observation and the two mutually conjugate entangled-state representations, we then derive a core operator for enabling a complex fractional Fourier transformation （CFrFT）, which also obeys the additive rule. In a similar manner, we also reveal the fractional transformation property for a type of Fresnel operator.

关键词： fractional Fourier transform core operator IWOP technique entangled state of con-tinuum variables Fresnel operator

Lethaclado acid A and B from Lethariella cladonioides

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Chinese Chemical Letters 2007年第12期18卷 1515-1517页

作者： Xin huang jun Li Jian hua Shen jun hua chen Drug Discovery and Design Centre State Key Laboratory of Drug Research Shanghai Institute of Materia Medica Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 201203 PR China

Two new compounds, lethaclado acid A （1） and B （2）, were isolated from the acetone extract ofLethariella cladonioides. Their structures were elucidated on the basis of 1D and 2D NMR as well as ESI-MS spectral data.

关键词： Lethariella cladonioides Depside Depsidone Lethaclado acid A Lethaclado acid B

National semantic infrastructure for traditional Chinese medicine

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Journal of Zhejiang University-Science C(Computers and Electronics) 2012年第4期13卷 311-314页

作者： hua-jun chen School of Computer Science and Technology Zhejiang UniversityHangzhou 310027China

1 Introduction Traditional Chinese medicine (TCM) is "the traditional medicine that originated in China,and is characterized by holism and treatment based on pattern identification/syndrome differentiation" (WHO,2007).In China,traditional medicine accounts for around 40％ of all healthcare delivered;in the West,TCM is increasingly adopted by medical practitioners as a form of complementary and altemative medicine (CAM) (WHO,2002).Both in China and in the West,scientists are attempting to bring the ancient heritage of TCM into line with modem standards,through the scientific development of TCM in the direction of evidence-based medicine (Qiu,2007).There is a pressing need for the digital preservation and global access of TCM knowledge assets.

关键词：中国传统医学基础设施传统医药语义辨证治疗世卫组织循证医学科学发展

Room temperature nonlinear mass sensing based on a hybrid spin-nanoresonator system

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Chinese Physics B 2020年第10期29卷 501-506页

作者： Jian-Yong Yang hua-jun chen School of Mechanics and Photoelectric Physics Anhui University of Science and TechnologyHuainan 232001China

We present a room temperature nonlinear mass sensing based on a hybrid spin-nanoresonator system with the microwave pump–probe technique and the spin readout technique, which includes a single spin of nitrogen–vacancy (NV) center in diamond and a nanomechanical cantilever. The resonance frequency of the nanoresonator can be measured with the nolinear Kerr spectrum, and the parameters that influence the nolinear Kerr spectrum are also investigated. Further, according to the relationship between frequency shifts and variable mass attached on the nanoresonator, this system can also be used to detect the mass of DNA molecules with the nolinear Kerr spectrum. Benefiting from the single spin of the NV center in diamond has a long coherence time at 300 K, the hybrid system can realize room temperature mass sensor, and the mass response rate can reach 2600 zg/Hz.

关键词： nonlinear mass sensing nitrogen-vacancy center nanomechanical resonator

Microstructure and properties of SiC gradiently coated C_f/C composites prepared by a RCLD method

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International Journal of Minerals,Metallurgy and Materials 2009年第3期16卷 334-338页

作者： jun-hua chen Guang-li chen Hao-ran Geng Yan Wang School of Materials Science and Engineering Shandong University Jinan 250061 China School of Materials Science and Engineering University of Jinan Jinan 250022 China

The SiC gradiently coated carbon fiber/carbon （Cf/C） composites were prepared by a two-step rapid chemical liquid deposition （RCLD） method. The microstructure and properties of the composites were investigated using X-ray diffraction, scanning electron microscopy together with energy dispersive X-ray analysis, bending tests, and oxidation tests. The experimental results show that the surface layer of the composites is composed of SiC, pyrocarbon, and carbon fibers. Their inner area consists of pyrocarbon and carbon fibers. The SiC content gradiently decreases with increasing distance from the outer surface to the center of the composites. Furthermore, the thickness of the SiC layer increases with increasing tetraethylorthosilicate content and deposition time. SiC coatings have no significant influence on the bending strength of the composites. However, the oxidation resistance of the composites increases with increasing thickness of the SiC layer.

关键词： carbon fiber reinforced composites chemical liquid deposition bending strength oxidation resistance

Evolution law of Wigner function in laser process

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Frontiers of physics 2013年第4期8卷 381-385页

作者： Rui He jun-hua chen Hong-Yi Fan Department of Material Science and Engineering University of Science and Technology of China Hefei 230026 China Department of Physics Shanghai Jiao Tong University Shanghai 200030 China

Based on the density operator＇s operator-sum representation recently obtained by Fan and Hu for a laser process （Opt. Commun., 2008, 281： 5571; Opt. Commun., 2009, 282： 932; Phys. Lett. B, 2008, 22： 2435）, we derive the evolution law of Wigner operator, the law is concisely expressed in T exp[-2T（ate-（k-g）t - a.）（ae-（k-g）t a）]; where g the normally ordered form A（a,a＊,t） = -T/π., and a are the cavity gain and the loss, respectively, and T - （a - g）（g-t-g - 2ge-2（k-g）t）-1. When 1 exp[-2（at a＊）（a a）] which is the initial Wigner operator. Using this t = O, A（a,a＊,t） →1/π , formalism the evolution law of Wigner functions in laser process can be directly obtained.

关键词： Kraus operator Wigner operator laser process

Flexible hollow TiO_(2)@CMS/carbon-fiber van der Waals heterostructures for simulated-solar light photocatalysis and photoelectrocatalysis

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Journal of Materials Science & Technology 2022年第3期98卷 143-150页

作者： hua-jun chen Yan-Ling Yang Xin-Xin Zou Xiao-Lei Shi Zhi-Gang chen School of Materials Science and Engineering Shaanxi Key Laboratory of Green Preparation and Functionalization for Inorganic MaterialsShaanxi University of Science and TechnologyXi’an 710021China School of Environment and Chemistry Luoyang Institute of Science and TechnologyLuoyang 471000China Centre for Future Materials University of Southern QueenslandSpringfield CentralQLD 4300Australia School of Mechanical and Mining Engineering The University of QueenslandBrisbaneQLD 4072Australia

The recycling technology of photocatalyst powdery has hardly been mature in the photocatalytic oxidation so *** this work,the hollow TiO_(2)microspheres with an appropriate thickness are confined in carbon microspheres(CMSs)to form hollow TiO_(2)@CMSs,which are physically integrated with carbon-fiber textile by van der Waals(vdW)interactions to generate separable and recyclable hollow TiO_(2)@CMSs/carbon-fiber vdW *** separable and recyclable heterostructures show remarkable oxidation of 2,*** our detailed characterization and density functional theory(DFT)calculations,we found that carbon fiber can trap electrons exerted from the excitation of hollow TiO_(2)@CMSs and creates holes in hollow TiO_(2)microspheres,which endow the carbon fiber with photocatalytic activity through coherent charge *** study indicates that our general strategy for the fabrication of hollow TiO_(2)@CMSs/carbon-fiber vdW heterostructures can be used as separable and recyclable photocatalyst and photoelectrocatalyst with potential industrial applications in environmentrelated fields.

关键词： Hollow nanostructure TiO_(2) Carbon fiber van der Waals heterostructure Photoelectrocatalysis

On the entangled fractional squeezing transformation

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Frontiers of physics 2015年第2期10卷 67-71页

作者： Hong-Yi Fan jun-hua chen Peng-Fel Zhang Department of Physics Ningbo University Ningbo 315211 China Department of Material Science and Engineering University of Science and Technology of China Hefei 230026 China Department of Modern Physics University of Science and Technology of China Hefei 230026 China

We propose an entangled fractional squeezing transformation （EFrST） generated by using two mu- tually conjugate entangled state representations with the following operator： e-iα（a1a2＋a1a2）eiπa2a2; this transformation sharply contrasts the complex fractional Fourier transformation produced by e-ia（a1a1＋a2a2）eiπa2a2 （see Front. Phys. DOI 10.1007/s11467-014-0445-x）. The EFrST is obtained by converting the triangular functions in the integration kernel of the usual fractional Fourier transformation into hyperbolic functions, i.e., tan α→ tanh α and sin α→ sinh α. The fractional property of the EFrST can be well described by virtue of the properties of the entangled state representations.

关键词： entangled fractional squeezing transformation entangled state representation squeezingoperator core operator

From Semantic Grid to Knowledge Service Cloud

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Journal of Zhejiang University-Science C(Computers and Electronics) 2012年第4期13卷 253-256页

作者： Zhao-hui WU hua-jun chen School of Computer Science and Technology Zhejiang UniversityHangzhou 310027China

1 Introduction The World Wide Web is a major breakthrough in the history of human communication and information sharing (Bemers-Lee et al.,2006).The Web has brought us a series of revolutionary tools,such as digital libraries,net meetings,e-mails,and data services,which have changed the face of scientific research and *** are increasingly relying on these tools to conduct their daily research,and to collaborate with their colleagues through distant communication and knowledge *** all these accomplishments,there are still gaps between what can be done using the current Web and what need to be done in an e-Science environment (Buetow,2005).

关键词：知识服务语义网格 e-Science 数字图书馆远距离通信信息共享数据服务电子邮件