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Journal of Thermal Science 2008年第3期17卷 212-217页

作者： Mizue MUNEKATA Ryuta KOSHIISHI Hiroyuki YOSHIKAWA hideki OHBA Department of Mechanical System Engineering

In our previous study, the effects of the interval between the cylinder and the airfoil on the aerodynamic sound were investigated and compared with the cases of single circular and single airfoil. In this study, the effects of the attack angle of the airfoil located downstream on the characteristics of aerodynamic sound and the wake structure are investigated at a given interval between the cylinder and the airfoil. It is found that the sound pressure level of DFN and the peak frequency decrease with increasing attack angle of airfoil because of the diffusive wake structure due to the increased back pressure of circular cylinder, which is caused by the blocking effect of airfoil. It is shown that the sound sources are corresponded to the attack points of shedding vortex form the upstream circular cylinder to the downstream airfoil. We conclude that the pressure fluctuation at the airfoil surface effects on the sound pressure level, from the flow visualizations and the exploration test of sound source.

关键词： aerodynamic sound wake interaction circular cylinder airfoil Karman's vortex flow visualization

Effect of Non-Newtonian Viscosity for Surfactant Solutions on Vortex Characteristics in a Swirling Pipe Flow

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Journal of Thermal Science 2005年第4期14卷 357-361,356页

作者： Mizue MUNEKATA Hidefumi TAKAKI hideki OHBA Kazuyoshi MATSUZAKI Kumamoto University 2-39-1 KurokamiKumamoto 860-8555Japan Tokyo Electron LTD. 650 Mitsuzawa Hosaka-cho NirasakiYamanashi 407-0192Japan

Effects of non-Newtonian viscosity for surfactant solution on the vortex characteristics and drag-reducing rate in a swirling pipe flow are investigated by pressure drop measurements, velocity profile measurements and viscosity measurements. Non-Newtonian viscosity is represented by power-law model （t= kD^π）. Surfactant solution used has shear-thinning viscosity with n 〈 1.0. The swirling flow in this study has decay of swirl and vortex-type change from Rankin＇s combined vortex to forced vortex. It is shown that the effect of shear-thinning viscosity on the decay of swirl intensity is different by vortex category and the critical swirl number with the vortex-type change depends on shear-thinning viscosity.

关键词： swirling flow drag reduction surfactant solution non-Newtonian fluid vortex LDV.

Contributions of the Secondary Jet to the Tangential Velocity Distribution and to the Collection Efficiency of the Fixed Guide Vane Type Axial Flow Cyclone Dust Collector

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Journal of Thermal Science 2015年第6期24卷 503-509页

作者： Akira Ogawa hideki Anzou So Yamamoto Mituru Shimagaki Tokyo Japan

In order to control the maximum tangential velocity V?m(m/s)of the turbulent rotational air flow and the collection efficiencyηc(%)using the fly ash of the mean diameter X R50=5.57?m,two secondary jet nozzles were installed to the body of the axial flow cyclone dust collector with the body diameter D1=*** in order to estimate V?m(m/s),the conservation theory of the angular momentum flux with Ogawa combined vortex model was *** comparisons of the estimated results of V?m(m/s)with the measured results by the cylindrical Pitot-tube were shown in good *** also the estimated collection efficienciesηcth(%)basing upon the cut-size Xc(?m)which was calculated by using the estimated V?m(m/s)and also the particle size distribution R(Xp)were shown a little higher values than the experimental results due to the re-entrainment of the collected *** best method for adjustment ofηc(%)related to the contribution of the secondary jet flow is principally to apply the centrifugal effect?c(1).Above stated results are described in detail.

关键词： Axial Flow Cyclone Dust Collector Maximum Tangential Velocity Cut-Size Particle Size Distribution Collection Efficiency Reynolds number Centrifugal Effect

Effects of Pulsation on Separated Flow and Heat Transfer in Enlarged Channel

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Journal of Thermal Science 2011年第1期20卷 70-75页

作者： Hiroyuki YOSHIKAWA Tomonori KAI Mizue MUNEKATA hideki OHBA Dept.of Mechanical System Engineering Kumamoto University2-39-1 KurokamiKumamoto 860-8555Japan Graduate School of Science and Technology Kumamoto University2-39-1 KurokamiKumamoto 860-8555Japan Kikuyo KikuchiKumamoto 869-1101Japan

Numerical results of three-dimensional separated flow and heat transfer in an enlarged rectangular channel are presented in this *** expansion ratio and aspect ratio of the channel are 2.0 and 16.0,*** number of the flow is 200 and it is over the critical Reynolds *** the critical Reynolds number,the flow in the symmetric channel becomes asymmetric and deflects to one side of the *** of the pulsating fluctuation at the inlet upon the flow in the channel are *** is clarified that the inlet flow with a pulsating fluctuation of Strouhal number 0.05 and 0.10 strongly affects on the flow in the channel,and heat transfer on the walls is enhanced,especially on the wall surface covered with long separation *** the other hand,the pulsation of St=0.0125 oscillates the shear layer more weakly than that of St=0.05,0.10 and the enhancement of heat transfer is smaller,though some vortices are shed from the vicinity of the side wall near the reattachment *** oscillation of the main flow calms down gradually as the Strouhal number of the pulsation increases over *** influence of pulsation of St=0.20 on the flow is restricted in the near downstream of the step,and heat transfer on the walls is almost similar to that of the steady flow in the channel.

关键词： Pulsating Fluctuation Symmetric Enlarged Channel Separated Flow Heat Transfer

Distribution characteristics of inclusions along with the surface sliver defect on the exposed panel of automobile:A quantitative electrolysis method

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International Journal of Minerals,Metallurgy and Materials 2020年第11期27卷 1489-1498页

作者： Xiao-qian Pan Jian Yang Joohyun Park hideki Ono State Key Laboratory of Advanced Special Steel School of Materials Science and EngineeringShanghai UniversityShanghai 200444China Department of Materials Engineering Hanyang UniversityAnsan 426-791South Korea Faculty of Sustainable Design University of ToyamaToyama-ken 930-8555Japan

The specific distribution characteristics of inclusions along with the sliver defect were analyzed in detail to explain the formation mechanism of the sliver defect on the automobile exposed panel surface.A quantitative electrolysis method was used to compare and evaluate the three-dimensional morphology,size,composition,quantity,and distribution of inclusions in the defect and non-defect zone of automobile exposed *** Al2O3 inclusions were observed to be aggregated or chain-like shape along with the sliver defect of about 3–10μ*** aggregation sections of the Al2O3 inclusions are distributed discretely along the rolling direction,with a spacing of 3–7 mm,a length of 6–7 mm,and a width of about 3 *** inclusion area part is 0.04%–0.16%with an average value of 0.08%,the inclusion number density is 40 mm−2 and the inclusion average spacing is 25.13μ*** inclusion spacing is approximately 40–160μm,with an average value of 68.76μm in chain-like inclusion *** average area fraction and number density of inclusions in the non-defect region were reduced to about 0.002%and 1–2 mm^−2,respectively,with the inclusion spacing of 400μm and the size of Al2O3 being 1–3μm.

关键词： automobile exposed panel sliver defect quantitative electrolysis three-dimensional inclusions aggregated inclusions chain-like inclusions

Optical detection of quantum geometric tensor in intrinsic semiconductors

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Science China(Physics,Mechanics & Astronomy) 2021年第10期64卷 82-87页

作者： Zhi Li Shengli Zhang takami Tohyama Xiufeng Song Yu Gu Toshiaki Iitaka Haibin Su Haibo Zeng MIIT Key Lxiboratory of Advanced Display Materials and Devices Ministry of Industry and Information TechnologyInstitute of Optoelectronics&NanomaterialsNanjing University of Science and TechnologyNanjing 210094China Department of Applied Physics Tokyo University of ScienceKatsushikaTokyo 125-8585Japan Discrete Event Simulation Research Team R/KEN Center for Computational ScienceWako 351-0198Japan Department of Chemistry The Hong Kong University of Science and TechnologyHong KongChina

Quantum geometric tensor, including a symmetric real part defined as quantum metric and an antisymmetric part defined as Berry curvature, is essential for understanding many phenomena. In this study, we investigated the photogalvanic efect of semiconductors with time-reversal-invariant and spatial inversion symmetries using the quantum kinetic equation. We concluded that the integral of the symmetric(antisymmetric) part of quantum geometric tensor on the equal energy surface in momentum space, satisfying the resonance condition, is related to the generation rate of carriers in semiconductors under linearly(circularly) polarized light. Under additional bias voltage, the dc photocurrent is proportional to the bias voltage. Our study provided an alternative interpretation for the photogalvanic efect in the view of quantum geometric tensor. Additionally, it classified the intrinsic diference between linearly and circularly polarized optical fields.

关键词： quantum geometry photovoltaic efect nonlinear optics

Prediction of post-progression survival in patientswith advanced hepatocellular carcinoma treated with sorafenib by using time-dependent changes inclinical characteristics

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Hepatoma Research 2018年第3期4卷 1-8页

作者： Yoshiyuki Wada Yuko takami Hajime Matsushima Masaki Tateishi Tomoki Ryu Munehiro Yoshitomi hideki Saitsu Department of Hepato-Biliary-Pancreatic Surgery Clinical Research InstituteNational Hospital Organization Kyushu Medical CenterFukuoka 810-8563Japan

Aim: Sorafenib has been shown to improve time to tumor progression (TTP) and overall survival (OS) in patients with hepatocellular carcinoma (HCC);however, post-progression survival (PPS) has not been well characterized in these patients. This study aimed to evaluate the predictors of PPS by using time-dependent and dynamic changes in radiologic progression patterns, liver function, and performance status (PS) in patients with advanced HCC receiving sorafenib treatment. Methods: We retrospectively analyzed the clinical characteristics of 128 advanced HCC patients with Child-Pugh scores ≤ 7 at the initiation of sorafenib treatment. Results: The median TTP, OS, and PPS were 3.8, 15.6, and 9.9 months, respectively. At the time of confirmation of radiologic progressive disease (PD), a total of 46 (35.6%) patients showed impairments in their PS of ≥ +1 points over time. For the Child-Pugh score, 27 (21.1%) and 26 (10.9%) patients exhibited an impairment of ≥ +1 and ≥ +2 points, respectively. Multivariate analysis identified the following independent predictors of PPS: impairment in the PS score of ≥+1 point [hazard ratio (HR) 1.81, 95% confidence interval (CI) 1.16-2.82], impairment in the Child-Pugh score of ≥ +2 points (HR 3.70, 95% CI 1.68-8.15), radiologic pattern of progression (target lesion growth and emergence of a new lesion) (HR 2.91, 95% CI 1.79-2.91), a TTP < 4 months(HR 1.87, 95% CI 1.21-2.91), second-line treatment after radiologic confirmation of PD (HR 0.16, 95% CI 0.08-0.32), and continuous sorafenib treatment after radiologic confirmation of PD (HR 1.76, 95% CI 1.06-3.00). Conclusion: PPS in patients with advanced HCC can be characterized by using time-dependent dynamic changes in clinical parameters.

关键词： Contactin-associated protein-2 Isaac neuromuscular hyperexcitability neuromyotonia voltage-gated potassium channel

Quantitative evaluation of long-term liver repopulation and the reconstitution of bile ductules after hepatocellular transplantation

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World Journal of Gastroenterology 2005年第39期11卷 6176-6181页

作者： Yun-Wen Zheng Nobuhiro Ohkohchi hideki Taniguchi Department of Regenerative Medicine Graduate School of Medical Science Yokohama City University Yokohama 236-0004 Japan Department of Surgery Institute of Clinical Medicine University of Tsukuba Tsukuba 305-8575 Japan Research Unit for Organ Regeneration Center for Developmental Biology RIKEN Kobe 650-0047 Japan

AIM： The treatment of liver disease is severely limited by a shortage of donor livers. In trying to address this growing problem, hepatocellular transplantation （HTx） has received much attention as an alternative to whole organ transplant. However, the expansion of transplanted cells is at low level, and the reconstitution of functional liver tissue is limited by this cellular property. We set up an animal model to better understand cell dose effect and the kinetics of liver repopulation following HTx. METHODS： Dipeptidyl peptidase Ⅳ （DPPⅣ）-deficient rats treated with retrorsine and subjected to partial hepatectomy were infused with DPPⅣ-positive hepatocytes. Rats were injected with varying numbers of donor hepatocytes down to 100 cells low, and liver repopulation was examined at different time points up to 20 mo long. Repopulation was assessed by computer-aided quantitative detection. RESULTS： Transplanted hepatocytes underwent multiple rounds of proliferation and stably repopulated the injured livers after 20 mo and at all cell doses. Transplanted cells divided 14 times within the 3-mo time period following infusion, and the liver repopulation reached a plateau between 3 and 20 too. Approximately 90% replacement occurred. Donor-derived cells also reconstituted the bile ductules of the recipients. CONCLUSION： The ability of transplanted hepatocytes to fully reconstitute injured livers strongly supports further investigation into the clinical potential of HTx. Additionally, the observation that transplanted hepatocytes also form components of the biliary system suggests that these cells may have bi-potential property of the stem cells.

关键词： Hepatocellular transplantation Hepatic stem cell Kinetics Cell dose Long-term repopulation Bile ductules Quantification In viva, Therapeutic potential

Numerical Study on Particle Motions in Swirling Flows in a Cyclone Separator

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Journal of Thermal Science 2006年第2期15卷 181-185页

作者： Kazuyoshi MATSUZAKI Hideaki USHIJIMA Mizue MUNEKATA hideki OHBA Tokyo Electron LTD. 650 Mitsuzawa Hosaka-cho Nirasaki Yamanashi 407-0192 Japan Kumamoto University 2-39-1 Kurokami Kumamoto 860-8555 Japan

The purpose of this study is to establish the high-accurate prediction method of particle separation in a cyclone separator. Numerical simulation of the swirling flows in a cyclone separator is performed by using a large eddy simulation （LES） based on a Smagorinsky model. The validity of the simulation and the complicated flow characteristics are discussed by comparison with experimental results. Moreover, particle motions are treated by a Lagrangian method and are calculated with a one-way method. A performance for particle separation is predicted from the results of the particle tracing. As results of our investigation, the influences of the inserted height of the outlet pipe on the performance for particle separation of cyclone separator are shown.

关键词： cyclone separator swirling flow particle motion large eddy simulation

Graphene-Like Bilayer Hexagonal Silicon Polymorph

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Nano Research 2010年第10期3卷 694-700页

作者： Jaeil Bai hideki Tanaka Xiao Cheng Zeng Department of Chemistry and Nebraska Center for Materials and Nanoscience University of Nebraska-LincolnLincolnNebraska 68588USA Department of Chemistry Okayama UniversityOkayama 700-8530Japan

We present molecular dynamics simulation evidence for a freezing transition from liquid silicon to quasi-two-dimensional(quasi-2D)bilayer silicon in a slit *** new quasi-2D polymorph of silicon exhibits a bilayer hexagonal structure in which the covalent coordination number of every silicon atom is *** molecular dynamics simulations show that the stand-alone bilayer silicon(without the confinement)is still stable at 400 *** band-structure calculations suggest that the bilayer hexagonal silicon is a quasi-2D semimetal,similar to a graphene monolayer,but with an indirect zero band gap.

关键词： Bilayer hexagonal silicon slit pore semimetal two-dimensional polymorph