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Bionic Design and Finite Element Analysis of Elbow in Ice Transportation Cooling System

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Journal of Bionic Engineering 2010年第3期7卷 301-306页

作者： Dejun Miao~(1,2), Xiuhua Sui~3, Linjing Xiao~3 1. key laboratory of Mine Hazard prevention and Control (ministry of education, china), Shandong university of science and technology, Qingdao 266510, p. r. china 2. School of Architecture, Tsinghua university, Beijing 100084, p. r. china 3. College of Mechanical and electronic Engineering, Shandong university of science and technology, Qingdao 266510, p. r. china key laboratory of Mine Hazard prevention and Control (ministry of education China) Shandong University of Science and Technology Qingdao P. R. China School of Architecture Tsinghua University Beijing P. R. China College of Mechanical and electronic Engineering Shandong University of Science and Technology Qingdao P. R. China

With the increase in mining depth, mine heat harm has appeared to be more prominent. The mine heat harm could be resolvedor reduced by ice refrigeration. Thus, ice transportation through pipeline becomes a critical problem; typically flowresistance occurs in the elbow. In the present study, according to the analysis of the surface morphology of fish scale, abiomimetic functional surface structure for the interior wall of elbow is designed. Based on the theory of liquid-solid two phaseflow, a CFD numerical simulation of ice-water mixture flowing through the elbow is carried out using finite element *** experiments of pressure drop and flow resistance for both bionic and common elbows are conducted to test theeffect of the bionic elbow on flow resistance reduction. It is found that with the increase in the ice mass fraction in the ice-watermixture, the effect of bionic elbow on resistance reduction becomes more obvious.

关键词： bionic elbow two phase flow ice transportation flow resistance reduction pressure loss

Using factor analysis scales of generalized amino acid information for prediction and characteristic analysis of β-turns in proteins based on a support vector machine model

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science china Chemistry 2010年第5期53卷 1160-1166页

作者： LIANG GuiZhao & ZHAO Wei key laboratory of Biorheological science and technology(Chongqing university),ministry of education Bioengineering College,Chongqing university,Chongqing 400044,china key laboratory of Biorheological science and technology (Chongqing university) Ministry of Education Bioengineering College Chongqing University Chongqing China

This paper offers a new combined approach to predict and characterize β-turns in *** approach includes two key steps,i.e.,how to represent the features of β-turns and how to develop a *** first step is to use factor analysis scales of generalized amino acid information(FASGAI),involving hydrophobicity,alpha and turn propensities,bulky properties,compositional characteristics,local flexibility and electronic properties,to represent the features of β-turns in *** second step is to construct a support vector machine(SVM) predictor of β-turns based on 426 training proteins by a sevenfold cross validation *** SVM predictor thus predicted β-turns on 547 and 823 proteins by an external validation test,*** results are compared with the previously best known β-turn prediction methods and are shown to give comparative *** significantly,the SVM model provides some information related to β-turn residues in *** results demonstrate that the present combination approach may be used in the prediction of protein structures.

关键词： β-turns factor analysis scales of generalized amino acid information support vector machine

Soft magnetic properties of (Ni_(50)Fe_(50)) SiO_2 granular thin films for high frequency application

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rare Metals 2006年第Z1期25卷 650-654页

作者： YANG Xiaolin GE Shihui rUAN Chengli College of physics and electronic science University of Electronic Science and Technology of China Chengdu 610054 China Key Laboratory for Magnetism and Magnetic Materials of Ministry of EducationLanzhou University Lanzhou 730000 China College of Physics and Electronic Science University of Electronic Science and Technology of China Chengdu 610054 China

A series of (Ni50Fe50)x(SiO2)(1-x) films with different volume fraction x was fabricated by magnetron co-sputtering technique. The microstructure, magnetic and electrical properties were investigated systematically by using X-ray diffraction, transmission electronic microscope, vibrating sample magnetometer and the traditional four point measurement method of resistivity. The results show that the samples consist of nano-scaled Ni50Fe50 metallic particles with fcc structure uniformly embedded in amorphous insulating SiO2 matrix, and the particle size decreases with the decrease of x. The rapid change of coercivity with x is observed, and a minimum value 160 A·m-1 of Hc was obtained for the sample of x=0.83 with film thickness of 180 nm, which can be contributed to the exchange coupling between nano-scaled Ni50Fe50 particles. At the frequency lower than 1 GHz, the real part μ′ of complex permeability keeps about 110 and the image part μ″ is less than 15. Besides, this film exhibits high resistivity ρ=263 μΩ·cm, high saturation magnetization 4πMs=1.25 T, high in-plane magnetic anisotropy field Hk=6.37 kA·m-1, and the ferromagnetic resonance (FMr) frequency is estimated to be 2.8 GHz. Therefore, this film can be used in high frequency devices operating over 2 GHz.

关键词： thin films nanostructure magnetic properties

A Binder of phosphogypsum-Ground Granulated Blast Furnace Slag-Ordinary portland Cement

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Journal of Wuhan university of technology(Materials science) 2011年第3期26卷 548-551页

作者：黄赟 key laboratory of Silicate Materials science and Engineering Ministry of EducationWuhan University of Technology

A new hydraulic cementitious binder was developed by mainly utilizing industrial byproducts phosphogypsum（pG）and ground granulated blast furnace slag（GGBFS）with small addition of ordinary portland cement（OpC）.The hydration process and microstructure were studied by X-ray diffraction（XrD） and scanning electronic microscopy（SEM）.OpC hydrated first at early age to form primarily C-S-H gel,ettringite and calcium hydroxide（CH）.GGBFS activated by CH and sulfate ions hydrated continuously at later age,producing more and more hydration products,C-S-H gel and *** the paste developed a denser microstructure and its strength *** 28 d compressive strength of the mixture of 50%pG,46% GGBFS and 4%OpC exceeded 45 *** setting time was faster and 3 d and 7 d strength were higher when the proportion of OpC *** the 28 d strength decreased when OpC exceeded 4%due to large amount of ettringite formed at late hydration age which damaged the microstructure.

关键词： phosphogypsum ground granulated blast furnace slag hydraulic cementitious binder

photonic band gap from periodic structures containing anisotropic nonmagnetic left-handed metamaterial

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Chinese Optics Letters 2010年第4期8卷 431-434页

作者：唐婷婷陈福深孙豹 key laboratory of Broadband Optical Fiber Transmission and Communication Networks in university of electronic science and technology of china Ministry of Education Department of Optoelectronic technology Chengdu University of Information Technology key laboratory of Broadband Optical Fiber Transmission and Communication Networks in university of electronic science and technology of china ministry of education

We demonstrate a photonic band gap（pBG） from one-dimensional（1D） periodic structures created by a double-layer unit cell with an air layer and an anisotropic nonmagnetic left-handed metamaterial（LHM） layer whose permittivity elements are partially *** requirements imposed on the materials and structures to realize a pBG are derived when the frequency is above or below the cutoff frequency,and the transmission properties of the pBG are discussed by utilizing 4×4 transfer-matrix method with dispersive semiconductor metamaterial.

关键词： Anisotropy Cutoff frequency Energy gap Metamaterials photonic band gap Transfer matrix method

Microstructures and fatigue-free properties of the La^(3+) and Nd^(3+) doped Bi_4Ti_3O_(12) thin films prepared by modified sol-gel technique

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science china(Technological sciences) 2008年第11期51卷 1843-1849页

作者： LI MeiYa1,2, pEI Ling1, LIU Jun1, YU BenFang1, GUO DongYun1, SUN XiaoHua3 & ZHAO XingZhong1,2 1 Department of electronic science and technology, School of physical science and technology, Wuhan university, Wuhan 430072, china 2 key laboratory of Acoustic and photonic Material and Device of the ministry of education, Wuhan Uni- versity, Wuhan 430072, china 3 School of Mechanical and Material Engineering, china Three Gorges university, Yichang 443002, china Department of electronic science and technology School of Physical Science and Technology Wuhan University Wuhan China key laboratory of Acoustic and photonic Material and Device of the ministry of education Wuhan University Wuhan China School of Mechanical and Material Engineering China Three Gorges University Yichang China

Ferroelectric Bi3.25La0.75Ti3O12 (BLT) and Bi3.15Nd0.85Ti3O12 (BNT) thin films were fab- ricated on pt/TiO2/SiO2/Si (100) substrates by a modified sol-gel technique. X-ray diffraction indicated that these films were of single phase with random polycrystal- line orientations. The surface morphologies of the films were observed by scanning electron microscope, showing uniform, dense films with grain size of 50―100 nm. Well-saturated hysteresis loops of the films were obtained in metal-ferroelectric- metal type capacitors with Cu top electrodes at an applied voltage of 400 kV/cm, giving the remanent polarization (2pr) and coercive field (2Ec) values of the films of 25.1 μC/cm2 and 203 kV/cm for BLT, and 44.2 μC/cm2 and 296 kV/cm for BNT, re- spectively. Moreover, these capacitors did not show fatigue behaviors after up to 1.75×1010 switching cycles at the test frequency of 1 MHz, suggesting a fatigue-free character. The influences of the La3+ and Nd3+ doping on the properties of the films were comparatively discussed.

关键词： bismuth oxides ferroelectrics fatigue sol-gel technique

Multiparty simultaneous quantum identity authentication with secret sharing

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science china(physics,Mechanics & Astronomy) 2008年第3期51卷 321-327页

作者： YANG YuGuang1,2,WEN QiaoYan3 & ZHANG Xing4,5 1 College of Computer science and technology,Beijing university of technology,Beijing 100022,china 2 State key laboratory of Information Security (Graduate university of the Chinese Academy of sciences),Beijing 100049,china 3 School of science,Beijing university of posts and Telecommunications,Beijing 100876,china 4 Institute of electronic technology,Information Engineering university,Zhengzhou 450004,china 5 Trusted Computing laboratory,Beijing university of technology,Beijing 100022,china College of Computer science and technology Beijing University of Technology Beijing China State key laboratory of Information Security (Graduate university of the Chinese Academy of sciences) Beijing China School of science Beijing University of Posts and Telecommunications Beijing China Institute of electronic technology Information Engineering University Zhengzhou China Trusted Computing laboratory Beijing University of Technology Beijing China

Two multiparty simultaneous quantum identity authentication (MSQIA) protocols based on secret sharing are presented. All the users can be authenticated by a trusted third party (TTp) simultaneously. In the first protocol,the TTp shares a random key K with all the users using quantum secret sharing. The ith share acts as the authentication key of the ith user. When it is necessary to perform MSQIA,the TTp generates a random number r secretly and sends a sequence of single photons encoded with K and r to all the users. According to his share,each user performs the corresponding unitary operations on the single photon sequence sequentially. At last,the TTp can judge whether the impersonator exists. The sec-ond protocol is a modified version with a circular structure. The two protocols can be efficiently used for MSQIA in a network. They are feasible with current technol-ogy.

关键词： quantum identity authentication secret sharing quantum cryptography

Theoretical observation of hexaatomic molecules containing pentacoordinate planar carbon

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science china Chemistry 2008年第11期51卷 1030-1035页

作者： LUO Qiong State key laboratory of Explosion science and technology, Beijing Institute of technology, Beijing 100081, china State key laboratory of Explosion science and technology Beijing Institute of Technology Beijing China

The smallest molecules up to date containing a D5h pentacoordinate planar carbon (ppC) atom, CBe5 and CBe54-, are presented by means of ab initio calculations. To gain a better understanding about which electronic factors contribute to their stabilization, natural bond orbital (NBO) analysis and the nucleus independent chemical shifts (NICS) were calculated. The data reported here suggest that D5h CBe5 is σ aromaticity in nature, while in D5h CBe54- π aromaticity is dominating. The classical octet rule is well satisfied in both molecules, and is one of the fundamental reasons to understand the stability of the pentagon structures. The Be5 ring serves as σ donor in D5h CBe5, and π-acceptor in D5h CBe54-. The D5h CBe54- possessing 18 valence electrons with a closed-shell electron configuration is the most plau-sible candidate for experimental detection.

关键词： pentacoordinate planar carbon Be5 ring ab initio

A new grid-associated algorithm in the distributed hydrological model simulations

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science china(Technological sciences) 2010年第1期53卷 235-241页

作者： XU rui1,2,HUANG XiaoXue1,LUO Lin1 & LI ShaoCai3 1 State key laboratory of Hydraulics and Mountain river Engineering College of Architecture and Environment,sichuan university,Chengdu 610065,china 2 College of electronic Engineering,Guilin university of electronic technology,Guilin 541004,china 3 College of Life sciences,sichuan university,Chengdu 610065,china State key laboratory of Hydraulics and Mountain river Engineering College of Architecture and Environment Sichuan University Chengdu China College of electronic Engineering Guilin University of Electronic Technology Guilin China College of Life sciences Sichuan University Chengdu China

This paper presents a new grid-associated algorithm to improve the performance of a D8 algorithm based distributed hydrological model *** algorithm is based on the well known single-flow D8 algorithm of grid *** algorithm allocates calculation priorities according to the distance between the units and the outlet,then carries out the ergodic computations of the hydrological units according to the priority *** the parallelized algorithm,a standard thread-level shared memory system for parallel programming(OpenMp-Open specifications for Multi processing) was introduced,and the parallel coding was implemented in C lan-guage.A case study showed that the absolute speed-up ratio of the grid-associated algorithm is 1.64 over the original D8 algorithm,and the linear speed-up ratio of the parallel associated algorithm is 2.42 under 4 *** parallel grid-associated algorithm can be applied to a variety of research fields that use the grid method.

关键词： distributed hydrological model grid-association algorithm OpenMp parallel computing