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Scale Effects on Propeller Cavitating Hydrodynamic and Hydroacoustic Performances with Non-uniform Inflow

Chinese Journal of Mechanical Engineering 2013年第2期26卷 414-426页

作者： YANG Qiongfang WANG Yongsheng zhang zhihong College of Marine Power Engineering Naval University of Engineering College of Science Naval University of Engineering

Considering the lack of theoretical models and ingredients necessary to explain the scaling of the results of propeller cavitation inception and cavitating hydroacoustics from model tests to full scale currently, and the insufficient reflection of the nuclei effects on cavitation in the numerical methods, the cavitating hydrodynamics and cavitation low frequency noise spectrum of three geometrically similar 7-bladed highly skewed propellers with non-uniform inflow are addressed. In this process, a numerical bridge from the multiphase viscous simulation of propeller cavitation hydrodynamics to its hydro-acoustics is built, and the scale effects on performances and the applicability of exist scaling law are analyzed. The effects of non-condensable gas（NCG） on cavitation inception are involved explicitly in the improved Sauer＇s cavitation model, and the cavity volume acceleration related to its characteristic length is used to produce the noise spectrum. Results show that, with the same cavitation number, the cavity extension on propeller blades increases with diameter associated with an earlier shift of the beginning point of thrust decline induced by cavitation, while the three decline slopes of thrust breakdown curves are found to be nearly the same. The power of the scaling law based on local Reynolds number around 0.9R section is determined as 0.11. As for the smallest propeller, the predominant tonal noise is located at blade passing frequency（BPF）, whereas 2BPF for the middle and both 2BPF and 3BPF for the largest, which shows the cavitating line spectrum is fully related to the interaction between non-uniform inflow and fluctuated cavity volume. The predicted spectrum level exceedance from the middle to the large propeller is 6.65 dB at BPF and 5.94 dB at 2BPF. Since it just differs less than 2 dB to the increment obtained by empirical scaling law, it is inferred that the scale effects on them are acceptable with a sufficient model scale, and so do the scaling

关键词： propeller cavitation inception cavitation noise scale effect cavitation model turbulence model

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Work conjugate principle-constrained volume averaging technique for multiphase porous media

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Science China(Technological Sciences) 2017年第12期60卷 1966-1974页

作者： zhang zhihong XU ZhaoGang XU ChengShun DU XiuLi Key Lab of Urban Security and Disaster Engineering Ministry of Education Beijing University of Technology Beijing 100124 China

Volume averaging is a standard method for the development of macroscopic balance equations for modelling the thermodynamic behaviors of multiphase porous media. However, work conjugate principle which is a common practice in continuum mechanics is not emphasized by the volume averaging technique resulting in the macroscopic balance equations are not capable of comprehensively describing the kinematic behaviors of multiphase porous media due to the loss of essential macroscopic variables. This study derives the macroscopic mass and momentum balance equations for the pore fluid of a fluid-solid porous medium by use of the volume averaging technique. We show(1) if the procedure of the volume averaging is implemented in its traditional manner, only the average flux of the pore fluid described by its mass average velocity is captured;(2) if the work conjugate principle is employed to define a work-conjugate velocity for the pore fluid at the macroscale, both the average flux(described by the mass average velocity) and the dispersive flux(described by the deviation of the mass average velocity from the work-conjugate one) are reproduced. This theoretical analysis demonstrates that the work conjugate principle is an essential thermodynamic constraint to improve the volume averaging technique, in the sense that the macroscopic balance equations are required to be capable of comprehensively describing the macroscopic kinematic behaviors of multiphase porous media.

关键词： volume averaging technique work conjugate principle work-conjugate velocity dispersive flux multiphase porous media

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Cerebrospinal fluid and blood biomarkers in the diagnostic assays of Alzheimer's disease

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Journal of Innovative Optical Health Sciences 2022年第1期15卷 32-56页

作者： Liding zhang Xiaohan Liang zhihong zhang Haiming Luo Britton Chance Center for Biomedical Photonics Wuhan National Laboratory for Optoelectronics Huazhong University of Science and Technology Wuhan Hubei 430074P.R.China MoE Key Laboratory for Biomedical Photonics School of Engineering Sciences Huazhong University of Science and Technology Wuhan Hubei 430074P.R.China

The anti-amyloid-j(anti-Aβ)fibrils and soluble oligomers antibody aducanumab were approved to effectively slow down the progression of A lzheimer's disease(AD)at higher doses in 2019,reaffirming the therapeutic effects of targeting the core pathology of AD.A timely and accurate diagnosis in the prodromal or pre-dementia stage of AD is essential for patient recruitment,stratifcation,and monitoring of treat ment effects.A D core biomarkers amyloid-B(Aβ1-42),total tau(t-tau),and phosphorylated tau(p-tau)have been clinically validated to reflect AD-type pathological changes through cerebrospinal fuid(CSF)measurement or positron-emission to-mography(PET)and found to have high diagnostic performance for AD identification in the stage of mild cognitive *** development of ultrasensitive immunoassay technology enables AD pathological proteins such as tau and neurofilament light(NFL)to be measured in blood ***,combined biomarker detection or targeting multiple biomarkers in immunoassays will increase detection sensitivity and specifcity and improve diagnostic accuracy..This review summarizes and analyzes the performance of current detection methods for early diagnosis of AD,and provides a concept of detection method based on multiple biomarkers instead of a single target,which may become a potential tool for early diagnosis of AD in the future.

关键词： Alzheimer's disease cerebrospinal fluid blood biomarkers bispecific antibody diagnosis.

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Design of Bionic Saw Blade for Corn Stalk Cutting

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Journal of Bionic Engineering 2013年第4期10卷 497-505页

作者： Honglei Jia Changying Li zhihong zhang Gang Wang Key Laboratory of Bionic Engineering (Ministry of Education China) Jilin University Changchun 130022 P. R. China School of Biological and Agricultural Engineering Jilin University Changchun 130022 P. R. China

The serrated incisors of grasshopper [Chondracris rosea rosea （De Geer）] possess an advantageous capacity for cutting plant fiber. Inspired by this special geometrical structure of incisors, bionic saw blade was designed and manufactured. MATLAB software digital image processing technology was used to obtain outer margin profile from stereomicroscope pho- tograph of the serrated incisors. The outer margin profile of incisors was fitted and expressed by six-order polynomial function. To compare the cutting capacity of bionic and traditional saw blades, the internodes of dry corn stalks were cut perpendicularly. Cutting force-deformation characteristics were obtained by universal testing machine. The results of cutting experiments show that the maximum cutting force of bionic saw blade was 128.26 N, which is 15.87% lower than 152.45 N of traditional saw blade; the average cutting force of bionic saw blade was 51.56 N, which is 28.17% less than 71.78 N of traditional saw blade. Meanwhile, the cutting energy consumption of bionic saw blade was 8.95 J, which is 12.85% less than 10.27 J of traditional saw blade. Overall, the bionic saw blade can lead to noticeable reduction of the cutting force and energy. These results will be helpful for designing cutting elements of corn stalk harvesting, biomass size reduction and other processing machinery.

关键词： bionic saw blade grasshopper incisors corn stalk edge detection cutting experiment

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Phase equilibria and crystal structure of ternary compounds in Al-rich corner of Al-Er-Y system at 673 and 873 K

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Journal of Materials Science & Technology 2021年第1期60卷 128-138页

作者： Xiaoxu Liu Yong Du Shuhong Liu Kaiming Cheng zhihong zhang State Key Laboratory of Powder Metallurgy Central South UniversityChangsha410083China Shandong Provincial Key Laboratory of High Strength Lightweight Metallic Materials Advanced Materials InstituteQilu University of Technology(Shandong Academy of Sciences)Jinan250014China Inner Mongolia Niobium Metallurgical Engineering Laboratory Baotou Research Institute of Rare EarthsBaotou014030China

Phase equilibria in the Al-rich corner of the Al-Er-Y ternary system from 65 at.% to 100 at.% Al at 673 and873 K were investigated,and the two isothermal sections were established by X-ray diffraction(XRD),scanning electron microscope(SEM) and electron probe micro analysis(EPMA).Three ternary-phase regions are observed and the phase relations are similar at both isothermal *** are two ternary compounds,and a complete crystal structures and composition ranges of the two ternary compounds are determined as τ_(1)(Al_(75-76)Er_(15-22)Y_(2-10),R-3 m) and τ_(2)(Al_(75-76)Er_(11-17)Y_(7-14),P6_(3)/mmc) via XRD,focused ion beam coupled with transmission electron microscope(FIB-TEM) and ***,the solubilities of the third element in the binary compounds at both temperatures are *** solubility of Er inβ-Al_(3) Y phase reaches to 6.6 at.% and that of Y in Al_(3) Er phase reaches to 1.5 at.% after annealing at 873 *** temperature effect is not obvious for the phase equilibria at 673 and 873 K,but it increases the solubility of Er in β-Al_(3) Y,while it is not obvious for both the solubility of Y in Al_(3) Er and that of Er and Y in(Al).The phase equilibria of the Al-Er-Y ternary system determined by the present work have provided new phase diagram data for a future thermodynamic assessment of this system.

关键词： Aluminium alloy Phase equilibria Al-Er-Y XRD EPMA TEM

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Highly Sensitive Functionalized Conducting Copolypyrrole Film for DNA Sensing and Protein-resistant

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Chinese Journal of Chemistry 2012年第2期30卷 259-266页

作者： zhang,zhihong Li,Guijuan Yan,Fufeng zhang,Zhonghou Fang,Shaoming Henan Provincial Key Laboratory of Surface&Interface Science Zhengzhou University of Light IndustryZhengzhouHenan 450002China

In order to exploit the applications ofpolypyrrole （PPy） derivatives in biosensors and bioelectronics, the different immobilization mechanisms of biomolecules onto differently functionalized conducting PPy films are investigated. Pyrrole and pyrrole derivatives with carboxyl and amino groups were copolymerized with ω-（N-pyrrolyl）-octylthiol self-assembled on Au surface by the method of the chemical polymerization to form a layer of the copolymer film, i.e., poly[pyrrole-co-（N-pyrrolyl）-caproic acid] （poly（Py-co-PyCA）） and poly[pyrrole-co-（N-pyrrolyl）-hexylamine] （poly（Py-co-PyHA））, in which the carboxyl groups in poly（Py-co-PyCA） were activated to the ester groups. Based on the structure characteristics, the immobilization/hybridization of DNA molecules on PPy, poly（Py-co-PyCA） and poly（Py-co-PyHA） were surveyed by cyclic voltammograms measurements. For differently functionalized copolymers, the immobilization mechanisms of DNA are various. Besides the electrochemical properties of the composite electrodes of PPy and its copolymers being detected before and after bovine serum albumin （BSA） adsorption, the kinetic process of protein binding was determined by surface plasmon resonance of spectroscopy. Since few BSA molecules could anchor onto the PPy and its copolymers surfaces, it suggests this kind of conducting polymers can be applied as the protein-resistant material.

关键词： conducting polymer polypyrrole cyclic voltammograms DNA immobilization protein adsorption

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Regenerating Plants from Cryopreserved Adventitious Buds of Haploids in Rice

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Wuhan University Journal of Natural Sciences 1999年第1期4卷 117-119页

作者： zhang, zhihong Hu, zhangli College of Life Sciences Wuhan University Wuhan China

A large number of adventitious buds were induced from in vitro cultured young inflorescences of haploids of *** been subcultured on solidified subculture media at 26 ℃ for 7 days ,the adventitious buds were loaded into 1.8 mL plastic cryotubes with cryoprotectant and kept on ice for 45 60 *** cooled at a rate of 1.0℃/min down to -40℃,the samples were kept in liquid *** adventitious buds which have been cryopreserved for about 30 days were thawed rapidly in 38 40℃water and then plated on solidified MS medium containing 3 % sucrose,0.5 mg/L NAA and 2.0 mg/L *** plated, 23% 32 % of adventitious buds resumed growth and 15% 22 % regenerated *** results of this work indicated that the adventitious buds derived from in vitro cultured young inflorescences is a critical factor for the success and subculturing adventitious buds on MS medium containing 3% sucrose and 4% sorbitol or 20% potato extract is essential to the *** effective cryoprotectant is 10 % DMSO(dimethyl sulfoximide)+0.5 mol/L sorbitol.

关键词： Oriza sativa ,haploid adventitious bud,cryopreservation

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Lithium Behavior in Salt-water System Explored by Molecular Dynamics Simulation

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Journal of Wuhan University of Technology(Materials Science) 2020年第6期35卷 1016-1020页

作者： MA Yanfang LIU Jianchuan LI Kanshe zhang zhihong Chemistry and Chemical Engineering College Xi’an University of Science and TechnologyXi’an 710054China Key Laboratory of Comprehensive and Highly Efficient Utilization of Salt Lake Resources Qinghai Institute of Salt LakesChinese Academy of SciencesXining 810008China Key Laboratory of Salt Lake Resources Chemistry of Qinghai Province Xining 810008China Beijing National Laboratory for Molecular Sciences and State Key Laboratory of Molecular Reaction Dynamics Institute of ChemistryChinese Academy of SciencesBeijing 100190China Innovation Academy for Green Manufacture Chinese Academy of SciencesBeijing 100190China

The molecular dynamics simulation method was adopted to study the transient characteristics of Li^+,CO3^2-,and SO4^2- in Na^+,K^+,Li^+,Cl^-,and SO4^2-/H2O *** composition of Na^+,K^+,Li^+,Cl^-,SO4^2- and CO3^2- was selected to optimize the initial structural model and conduct dynamic *** mean azimuth shift and diffusion coefficient of Li^+,CO3^2-,and SO4^2- in the system,the radial distribution function and potential energy between Li^+ and -OW,SO4^2- and -OW as well as CO3^2- and -OW,and the dielectric constant of hydrogen bond were expounded and *** the same time,the Li enrichment behavior in the evaporation process of salt lake brine was analyzed based on the simulated *** results show that the simulation results are in good agreement with the experimental values,which verifies that,compared with other ions,the crystallization of Li^+ and SO4^2- occurs earlier after reaching saturation.

关键词： salt lakes Li^+ CO3^2- SO4^2- MD salt water system

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Leakage of nuclear material powder from pressure container through a small orifice

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Particuology 2014年第3期12卷 117-123页

作者： Longbo Liu Yanmin Wu Yongyang Su Hanbing Tang zhihong zhang Ping Huang Lili zhang Lixing zhang Northwest Institute of Nuclear Technology

Because of the radioactivity and toxic nature of nuclear materials, their containment within oxide matrices, encased in sealed containers, has been proposed as a suitable means for storage and transportation. However, container failures because of cracks or small orifices present a major leakage risk for nuclear materials, consequently posing a significant hazard to the environment and human beings. In this study, terbium oxide powder was used as a nuclear material representative to examine the leakage of nuclear material powder through orifices located at the base of a pressure container. The dependence of the orifice diameter, the powder layer thickness, and the internal pressure of the container on the leakage mechanism and amount was examined. A simplified model correlating the dependence of the above-mentioned parameters to determine the utmost leakage amount was also developed based on the present results. The leakage of the nuclear material powder was assessed by measuring its concentration using an optical particle counter. The diameter of the orifice determined the powder leakage mechanism, which in turn influenced the amount of leakage produced. Comparison studies showed that unlike the changes in the differential pressure, the volume of the container has little effect on the leakage amount. Under sufficiently high internal pressures, the oxide powder can be released as a fine aerosol. The work is not only crucial from the nuclear safety aspect, but is also beneficial for the safe application of powder and nanoparticles.

关键词： Nuclear materials Powder Leakage Risk assessment

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KillerRed protein based in vivo photodynamic therapy and corresponding tumor metabolic imaging

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Journal of Innovative Optical Health Sciences 2016年第1期9卷 21-30页

作者： Qiaoya Lin Shuang Sha Fei Yang Honglin Jin zhihong zhang Britton Chance Center for Biomedical Photonics Wuhan National Laboratory for Optoelectronics Huazhong University of Science and Technology Wuhan 430074 P.R.China MoE Key Laboratory for Biomedical Photonics Department of Biomedical Engineering Huazhong University of Science and Technology Wuhan 430074 P.R.China

Photodynamic therapy(PDT)gains wide attention as a useful therapeutic method for *** is mediated by the oxygen and photosensitizer under the specific light irradiation to produce the reactive oxygen species(ROS),which induce cellular toxicity and regulate the redox potential in tumor ***,genetic photosensitizers of low toxicity and easy production are required to be ***,a unique red fluorescent protein exhibiting excellent phototoxic properties,has the potential to act as a photosensitizer in the application of tumor ***,the course of tumor redox metabolism during this treatment was rarely investigated so *** here,we investigated the effects of KillerRed-based PDT on tumor growth in vivo and examined the subsequent tumor metabolic states including the changes of nicotinamide adenine dinucleotide hydrogen(NADH)and flavoprotein(Fp),two important metabolic coenzymes of tumor *** showed the tumor growth had been significantly inhibited by KillerRedbased PDT treatment compared to control groups.A home-made cryo-imaging redox scanner was used to measure intrinsic fluorescence and exogenous KillerRed fluorescence signals in *** Fp signal was elevated by nearly 4.5-fold,while the NADH signal decreased by 66%after light irradiation,indicating that Fp and NADH were oxidized in the course of KillerRedbased ***,we also observed correlation between the fluorescence distribution of KillerRed and *** suggests that the KillerRed protein based PDT might provide a new approach for tumor therapy accompanied by altering tumor metabolism.

关键词： Reactive oxygen species redox metabolism flavoprotein nicotinamide adenine dinucleotide hydrogen

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