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Converting Molecular Vibration to Mechanical Wave for Bond-Selective Imaging of Deep Tissue

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Chinese Journal of Chemical Physics 2015年第4期28卷 -页

作者： jie Hui ji-xin Cheng Department of Physics and Astronomy Purdue University West Lafayette Indiana 47907 USA Weldon School of Biomedical Engineering Purdue University West Lafayette Indiana 47907 USADepartment of Chemistry Purdue University West Lafayette Indiana 47907 USA

As an emerging label-free imaging modality with chemical selectivity and millimeter-depth resolvability, vibrational photoacoustic imaging provides a new avenue to map chemical content in biological tissue. It heralds the potential for detection of white matter loss and regeneration, assessment of breast tumor margin, and clinical diagnosis of vulnerable plaques in atherosclerosis. In this work, we provide an overview of the development of bond-selective photoacoustic imaging and various biomedical applications enabled by this new technology.

关键词： Label-free Vibrational spectroscopy Chemical imaging

Improved space-time processing for X channel using precoders

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The Journal of China Universities of Posts and Telecommunications 2014年第5期21卷 31-36页

作者： TIAN xin-ji LI Ya School of Computer Science and Technology Henan Polytechnic University

The article investigates how to send perfect space-time codes with low feedback amount and symbol-by-symbol decoding for X channel using precoders. It is assumed that two users are introduced with two antennas and two receivers. Each user employs a rate-2 space-time block code and follows certain rule when sending codewords. The multi-user interference is eliminated by pre-coding at the transmitter and linear processing at the receiver. Compared with the existing scheme for the same scene, the proposed scheme greatly reduces feedback amount and improves the transmission efficiency, while keeping the same decoding complexity. Simulations demonstrate the validity of the proposed scheme.

关键词： X channel space-time code pre-coding multi-user interference feedback amount transmission efficiency

Hydrothermal Synthesis, Crystal Structure, and Characterization of a Novel Terbium(Ⅲ) Coordination Polymer Bridged by 5-Sulfoisophthalate Trivalent Anions

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Chemical Research in Chinese Universities 2007年第2期23卷 123-126页

作者： YUAN ji-xin XIONG jing School of Chemistry and Materials Science Wenzhou University Wenzhou 325027 P. R. China

Hydrothermal reaction of terbium（ Ⅲ） chloride with 5-sulfoisophthalic acid monosodium salt and 1,10-phenanthroline（phen） at 415 K resulted in the formation of a novel coordination polymer, [ Tb （sip）（phen）（H2O） ],（sip =5-sulfoisophthalate trivalent anion） with a three-dimensional network structure. Each centrosymmetrically related pair of terbium ions axe linked by two sip anions, forming a binuclear unit, and each binuclear unit links to four adjacent tetranuclear units, extending a two-dimensional hybrid layer at crystallographic bc plane. On the other hand, every three-terbium ion is connected by three sip anions, generating a trinuclear ring, and the trinuclear ring connects six neighboring trinuclear rings to produce another two-dimensional layer at crystallographic ab plane. Moreover, each sip anion acts as a pontadentate bridge, interconnecting two different types of layers to yield a novel three-dimensional framework.

关键词： Hydrothermal synthesis Terbium Three-dimensional network 5-Sulfoisophthalate trivalent anion

The Radial Structure of Pulsar Radio Emission Regions

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Chinese Journal of Astronomy and Astrophysics 2002年第5期2卷 454-462页

作者： xin-ji Wu Zhao-Kui Huang DepartmentofAstronomy PekingUniversityBeijing100871 TheChineseAcademyofSciences-PekingUniversityJointBeijingAstrophysicsCenter Beijing100871

An important parameter in the study of the radial structure of the pulsar radio emission region is the altitude of the emission, but this cannot be derived directly from the observations. The altitude can be expressed as a function of frequency, γv ∝v-ξ, and the method of K analysis can be used to calculate the power law index ?from observations at different frequencies. We have calculated the value of ?for 18 pulsars observed at two frequencies, 610MHz and 1408MHz and for three pulsars observed at three or more frequencies. The average value of ξ is 0.27, which indicates that the emission altitude increases with decreasing frequency and that the radial structure is compact.

关键词： stars: pulsars

An Estimation of the Initial Period of Pulsars

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Chinese Journal of Astronomy and Astrophysics 2003年第2期3卷 166-174页

作者： Zhan-Kui Huang xin-ji Wu DepartmentofAstronomy PekingUniversityBeijing100871 ChineseAcademyofSciences-PekingUniversityJointBeijingAstrophysicsCenter Beijing100871 NationalAstronomicalObservatories UromqiAs

The initial period of a pulsar is an important factor in our understanding of the formation of neutron stars and of the nature of the equation of state of neutron star matter. Up to now this quantity can only be obtained for a few pulsars for which accurate age and braking index are known. Based on the theory of the off-center dipole emission, in which pulsars obtain their high velocities depending on the initial periods, we calculate the initial period using the proper motion data. Because the orbital velocity of the progenitor and asymmetric kick in the supernova explosion may also contribute to the observed velocity of the pulsar, the derived values of initial periods are lower limits. For normal pulsars, the initial periods are in the range of 0.6 - 2.6ms. For the millisecond pulsars, the initial periods are comparable to their current periods, and the ratio between the initial period and the current period increases with the decrease of the current period. For PSR B1937+21 with the shortest period of 1.56ms, the ratio is 0.77.

关键词： pulsaxs - stars: neutron

Aerodynamics analysis of a hypersonic electromagnetic gun launched projectile

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Defence Technology（防务技术） 2020年第4期16卷 753-761页

作者： jian Shen Shao-bo Fan Ya-xin ji Qing-yu Zhu ji Duan College of Mechatronics Engineering North University of ChinaNo.3Xue Yuan RoadTai Yuan030051China Northwest Industries Group CO. Ltd.No.123Xing Fu Middle RoadXi'an710043China jilin jiangji Special Industries CO. Ltd.No.17Zun Yi West RoadJi Lin132021China AVIC China Aero-Polytechnology Establishment No.7Jing Shun RoadBeijing100028China

A hypersonic aerodynamics analysis of an electromagnetic gun(EM gun) launched projectile configuration is undertaken in order to ameliorate the basic aerodynamic characteristics in comparison with the regular projectile *** margin and pendulum motion analysis models have been applied to evaluate the flight stability of a new airframe *** a steady state computational fluid dynamics(CFD) simulation,the basic density,pressure and velocity contours of the EM gun projectile flow field at Mach number 5.0,6.0 and 7.0(angle of attack=0°) have been ***,the static margin values are enhanced dramatically for the EM gun projectile with configuration ***,lift and pitch property variations are all illustrated with the changes of Mach number and angle of attack.A particle ballistic calculation was completed for the pendulum *** results show that the configuration optimized projectile,launched from the EM gun at Mach number 5.0 to 7.0,acts in a much more stable way than the projectiles with regular aerodynamic layout.

关键词： Electromagnetic gun launched projectile Hypersonic aerodynamics Airframe configuration optimization Static margin Pendulum

Geometry Asymmetry of Mean Pulse Profile of Pulsar

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Chinese Physics Letters 1999年第4期16卷 307-309页

作者： PAN Jun WU xin-ji Department of Geophysics Peking UniversityBeijing 100871 Chinese Academic of Science-Peking University joint Beijing Astrophysical Center Beijing 100871

The effects of aberration,retardation and magnetic field sweep back,which are caused directly or indirectly by pulsar’s rapid rotation,are estimated in order to examine their influences on the geometry asymmetry of the mean pulse *** geometric asymmetry exhibits different behaviors at different *** millisecond pulsars incline to develop mean pulse profiles with asymmetric contrary to the normal *** pulsar J0437-4715 is analyzed as an example.

关键词： profile. pulsar rotation

Using concurrent lines in central catadioptric camera calibration

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Journal of Zhejiang University-Science C(Computers and Electronics) 2011年第3期12卷 239-249页

作者： Lei ZHANG xin DU ji-lin LIU Department of Information Science and Electronic Engineering Zhejiang University Hangzhou 310027 China

Central catadioptric cameras have been extensively adopted in robotics and surveillance due to their extensive field of *** attain precise 3D information in these applications,it is important to calibrate the catadioptric cameras *** existing calibration techniques either require prior knowledge of the mirror types,or highly depend on a conic estimation procedure,which might be ruined if there are only small portions of the conic visible on calibration *** this paper,we design a novel planar pattern with concurrent lines as a calibration rig,which is more robust in conic estimation since the relationship among lines is taken into *** on the line properties,we propose a rough-to-fine approach suitable for the new planar pattern to calibrate central catadioptric *** method divides the nonlinear optimization calibration problem into several linear sub-problems that are much more robust against *** calibration method can estimate intrinsic parameters and the mirror parameter simultaneously and accurately,without a priori knowledge of the mirror *** performance is demonstrated by both simulation and a real hyperbolic catadioptric imaging system.

关键词： Catadioptric Calibration Concurrent lines Conic estimation

NON-LINEAR OPTICAL IMAGING OF OBESITY-RELATED HEALTH RISKS:REVIEW

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Journal of Innovative Optical Health Sciences 2009年第1期2卷 9-25页

作者： THUC T.LE ji-xin CHENG Weldon School of Biomedical Engineering Purdue University West Lafayette Indiana 47907USA Department of Chemistry and Weldon School of Biomedical Engineering Purdue University West Lafayette Indiana 47907USA

This review highlights the recent applications of non-linear optical(NLO)microscopy to study obesity-related health risks.A strong emphasis is given to the applications of coherent anti-Stokes Raman scattering(CARS)microscopy where multiple non-linear optical imaging modalities including CARS,sum-frequency generation(SFG),and two-photon fluorescence are employed simultaneously on a single microscope *** examples on applications of NLO microscopy to study lipid-droplet biology,obesity-cancer relationship,atherosclerosis,and lipidrich biological structures are discussed.

关键词： Atherosclerosis coherent anti-Stokes Raman scattering lipid droplet mammary cancer non-linear optics obesity second harmonic generation sum-frequency generation twophoton fluorescence tumor stroma