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Transactions of Nonferrous Metals Society of China 2010年第4期20卷 707-711页

作者： HUANG Ying tanaka Mikiya Research Institute for Environmental Management Technology National Institute of Advanced Industrial Science and Technology （AIST） 16-10nogawa Tsukuba Ibaraki 305-8569 Japan School of Energy and Environment Southeast University Nanjing 210096 China

In view of the importance of solvent extraction of rare earth metals with the acidic organophosphorous reagent,the development of a chemically based model applicable to high concentration is *** the present study,the equilibrium distribution of dysprosium(Ⅲ)between an aqueous nitric acid solution and 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester (PC88A)was measured in the range of an initial aqueous dysprosium(Ⅲ)concentration from 1.0×10-3to 1.0×10-1kmol/m 3and PC88A concentration from 0.16 to 0.65 kmol/m3in Shellsol D70 as the *** obtained data were analyzed using the chemically based model in order to correlate the equilibrium distribution *** this model,dysprosium(Ⅲ)was assumed to be extracted with the PC88A dimer as a 1:3 complex,the activities were considered for the aqueous species,and the effective concentration of the PC88A dimer was calculated using Alstad's empirical *** a result,the apparent extraction equilibrium constant was determined to be 253(kmol·m- 3)-2with an excellent correlation between the experiment and calculation results in the wide range of the logarithm of the distribution ratio from-2 to *** conclusion,the methodology in this model would be effective for quantitative description of solvent extraction behavior of general rare earth elements as well as dysprosium.

关键词： solvent extraction dysprosium 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester(PC88A) nitric acid equilibrium

Influence of Coanda surface curvature on performance of bladeless fan

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Journal of Thermal Science 2014年第5期23卷 422-431页

作者： LI Guoqi HU Yongjun JIN Yingzi toshiaki Setoguchi Heuy Dong Kim Zhejiang Province Key Laboratory of Fluid Transmission Technology Zhejiang Sci-Tech University Department of Mechanical Engineering Saga University Honjo-machiSaga840-8502Japan School of Mechanical Engineering Andong National UniversitySeongcheon-Dong1375Gyeongdong-RDAndongGyeongsangnuk-DO760-749Korea

The unique Coanda surface has a great influence on the performance of bladeless ***,there is few studies to explain the relationship between the performance and Coanda surface curvature at *** order to gain a qualitative understanding of effect of the curvature on the performance of bladeless fan,numerical studies are performed in this ***,three-dimensional numerical simulation is done by Fluent *** the purpose to obtain detailed information of the flow field around the Coanda surface,two-dimensional numerical simulation is also *** types of Coanda surfaces with different curvature are designed,and the flow behaviour and the performance of them are analyzed and compared with those of the *** analysis indicates that the curvature of Coanda surface is strongly related to blowing performance,It is found that there is an optimal curvature of Coanda surfaces among the studied *** result shows that there is a special low pressure *** increasing curvature in Y direction,several low pressure regions gradually enlarged,then begin to merge slowly,and finally form a large area of low *** the analyses of streamlines and velocity angle,it is found that the magnitude of the curvature affects the flow direction and reasonable curvature can induce fluid flow close to the ***,it leads to that the curvature of the streamlines is consistent with that of Coanda ***,it also causes the fluid movement towards the most suitable *** study will provide useful information to performance improvements of bladeless fans.

关键词： bladeless fan Coanda surface velocity low pressure region curvature.

Direct measurement of the three-dimensional distribution of leaf area density and light conditions in a mature oak stand by the cube method

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林业研究:英文版 2023年第6期34卷 1817-1827页

作者： Chiharu Migita Yukihiro Chiba tanaka Kenzo Forestry and Forest Products Research Institute TsukubaIbaraki 305-8687Japan Japan International Research Centre for Agricultural Sciences TsukubaIbaraki 305-8686Japan

Although the distributions of foliage and light play major roles in various forest functions,accurate,nondestructive measurement of these distributions is difficult due to the complexity of the canopy *** evaluate the foliage and light distributions directly and nondestructively in a mature oak stand,we used the cube method by dividing the forest canopy into small cubes(50 cm per side)and directly measured leaf area density(LAD,the total one-sided leaf area per unit volume,i.e.,cube)and relative irradiance(RI)within each *** distribution of LAD and of RI was highly heterogeneous,even at the same canopy *** heterogeneity reflected the presence of foliage clusters associated with multiple forking *** relationship between cumulative LAD at the canopy surface and average RI followed the Beer-Lambert *** mean light extinction coefficient(K)was ***,K was overestimated by more than double(0.80)when calculated based on the classical method using RI at the forest *** overestimation was caused by the lower RI due to light absorption by nonleaf plant parts below the *** findings on the complex foliage and light distributions in canopy layers should help improve the accuracy of RI and K measurements and thus more accurate predictions of environmental responses and forest functions.

关键词： Beer-Lambert law Canopy structure Foliage cluster Leaf area density Leaf area index Relative light intensity

Detrital zircon geochronology of the Lutzow-Holm Complex,East Antarctica:Implications for Antarctica-Sri Lanka correlation

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Geoscience Frontiers 2018年第2期9卷 355-375页

作者： Yusuke Takamura toshiaki Tsunogae M.Santosh Yukiyasu Tsutsumi Graduate School of Life and Environmental Sciences University of TsukubaIbaraki 305-8572Japan Department of Geology University of JohannesburgAuckland Park 2006South Africa School of Earth Sciences and Resources China University of Geosciences Beijing29 Xueyuan RoadBeijing 100083China Centre for Tectonics Resources and Exploration Department of Earth SciencesUniversity of AdelaideSA 5005Australia Department of Geology and Paleontology National Museum of Nature and ScienceIbaraki 305-0005Japan

The Lützow-Holm Complex(LHC) of East Antarctica has been regarded as a collage of Neoarchean(ca.2.5 Ga), Paleoproterozoic(ca. 1.8 Ga), and Neoproterozoic(ca. 1.0 Ga) magmatic arcs which were amalgamated through the latest Neoproterozoic collisional events during the assembly of Gondwana supercontinent. Here, we report new geochronological data on detrital zircons in metasediments associated with the magmatic rocks from the LHC, and compare the age spectra with those in the adjacent terranes for evaluating the tectonic correlation of East Antarctica and Sri Lanka. Cores of detrital zircon grains with high Th/U ratio in eight metasediment samples can be subdivided into two dominant groups:(1) late Meso-to Neoproterozoic(1.1-0.63 Ga) zircons from the northeastern part of the LHC in Prince Olav Coast and northern Soya Coast areas, and(2) dominantly Neoarchean to Paleoproterozoic(2.8-2.4 Ga) zircons from the southwestern part of the LHC in southern Lutzow-Holm Bay area. The ca.1.0 Ga and ca. 2.5 Ga magmatic suites in the LHC could be proximal provenances of the detrital zircons in the northeastern and southwestern LHC, respectively. Subordinate middle to late Mesoproterozoic(1.3-1.2 Ga) detrital zircons obtained from Akarui Point and Langhovde could have been derived from adjacent Gondwana fragments(e.g., Rayner Complex, Eastern Ghats Belt). Meso-to Neoproterozoic domains such as Vijayan and Wanni Complexes of Sri Lanka, the southern Madurai Block of southern India, and the central-western Madagascar could be alternative distal sources of the late Meso-to Neoproterozoic zircons. Paleo-to Mesoarchean domains in India, Africa, and Antarctica might also be distal sources for the minor ~2.8 Ga detrital zircons from Skallevikshalsen. The detrital zircons from the Highland Complex of Sri Lanka show similar Neoarchean to Paleoproterozoic(ca. 2.5 Ga) and Neoproterozoic(ca. 1.0 Ga) ages, which are comparable with those of the LHC, suggesting that the two complexes might have form

关键词： The northern Lützow-Holm-Vijayan Complex Zircon U-Pb geochronology Crustal evolution Tectonic correlations Gondwana supercontinent

Vortices within the Separation Region in a Decelerating Channel Flow (Effect of Inlet Velocity Gradient)

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Journal of Thermal Science 2005年第4期14卷 341-345页

作者： Yoichi KINOUE toshiaki SETOGUCHI Mohammad MAMUN Norimasa SHIOMI Kenji KANEKO Department of Mechanical Engineering Saga University1HonjoSaga840-8502Japan

An experimental investigation was made into three-dimensional separated flow and the vortices within the flow separation in a decelerating channel flow generated by the suction from a porous side wall. The flows along the side and bottom walls were visualized by the surface tuft method. The turbulent internal flow was measured by the split-film probe to investigate the turbulent flow including the reverse flow. In the flow visualization for the strong decelerating flow （the suction flow ratio：0.8）, two typical flow patterns appear alternatively. One is that the flow near the bottom wall separates more upstream than the flow near the top wall and a clockwise vortex can be seen in the separation region. Another is the reversal flow pattern with a counterclockwise vortex. By the turbulent flow measurement using the split-film probe, two peaks of turbulence level are observed for the strong decelerating flow case. These peaks can be related with two flow patterns mentioned above.

关键词： vortices within the separation decelerating channel flow turbulent flow split-film probe

Control of Transonic Flow Fields Using Local Occurrence of Non-Equilibrium Condensation

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Journal of Thermal Science 2013年第4期22卷 327-332页

作者： Junji Nagao Shigeru Matsuo Tokitada Hashimoto toshiaki Setoguchi Heuy Dong Kim Department of Advanced Technology Fusion Saga University Institute of Ocean Energy Saga University School of Mechanical Engineering Andong National University

Control of supersonic flow fields with shock wave is important for some industrial fields. There are many studies for control of the supersonic flow fields using active or passive control. When non-equilibrium condensation occurs in a supersonic flow field, the flow is affected by latent heat released. Many studies for the condensation have been conducted and the characteristics have been almost clarified. Further, it was found that non-equilibrium condensation can control the flow field. In these studies, the condensation occurs across the passage of the flow field and it causes the total pressure loss in the flow field. However, local occurrence of non-equilibrium condensation in the flow field may change the characteristics of total pressure loss compared with that by the condensation across the passage of the nozzle and there are few for researches of locally occurred non-equilibrium condensation in supersonic flow field. The purpose in the present study is to clarify the effect of local occurrence of non-equilibrium condensation on the transonic flow field in a nozzle with a circular bump. As a result, local occurrence of non-equilibrium condensation reduced the shock strength and total pressure loss in the transonic flow field by flowing the moist air from trailing edge of the circular bump to the mainstream.

关键词： Compressible flow Transonic flow Shock wave Non-equilibrium condensation Circular bump

Unsteady Shock-Flow Characteristics in an Over-Expanded Rocket Nozzle

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Journal of Thermal Science 2010年第4期19卷 332-336页

作者： Jong Sung Lee Huey Dong Kim toshiaki Setoguchi Shigeru Matsuo School of Mechanical Engineering Andong National UniversityAndong760-749Korea Department of Mechanical Engineering Saga University1HonjoSagaJapan

A numerical investigation of transient side-loads in an axisymmetric over-expanded thrust optimized contour nozzle is *** nozzles experience side-loads during start-up and shut-down operations,because of the flow separation at nozzle *** types of flow separations such as FSS and RSS shock structure occur.A two-dimension numerical simulation has been carried out over an axisymmetric TOC nozzle to validate present results and investigate oscillatory flow characteristics for start-up *** Averaged Navier-Stokes equations are numerically solved using a fully implicit finite volume *** equations are solved by coupled implicit *** Stress turbulence model is *** computed pressure at the nozzle wall closely matched with experiment data.A hysteresis phenomenon has been observed between these two shock *** transition from FSS to RSS pattern during start-up process has shown maximum nozzle wall *** wall pressure and shear stress values have shown fluctuations during the FSS to RSS transition. The oscillatory pressure has been observed on the nozzle wall for high pressure *** results have shown that magnitude of the nozzle wall pressure variation is high for the oscillatory phenomenon.

关键词： Free shock separation Over-expansion flow Restricted shock separation Side-loads Supersonic nozzle

A Computational Study of Thrust Vectoring Control Using Dual Throat Nozzle

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Journal of Thermal Science 2010年第6期19卷 486-490页

作者： Choon Sik Shin Heuy Dong Kim toshiaki Setoguchi Shigeru Matsuo Department of Mechanical Engineering Andong National University Department of Mechanical Engineering Saga University

Dual throat nozzle (DTN) is fast becoming a popular technique for thrust vectoring. The DTN is designed with two throats, an upstream minimum and a downstream minimum at the nozzle exit, with a cavity in between the upstream throat and exit. In the present study, a computational work has been carried out to analyze the performance of a dual throat nozzle at various mass flow rates of secondary flow and nozzle pressure ratios (NPR). Two-dimensional, steady, compressible Navier-Stokes equations were solved using a fully implicit finite volume scheme. The present computational results were validated with available experimental data. Based on the present results, the control effectiveness of thrust-vectoring is discussed in terms of the thrust coefficient and the coefficient of discharge.

关键词： Compressible Flow Dual Throat Nozzle Thrust Vector Control Shock Wave Supersonic Flow

Prediction of the Curie temperature considering the dependence of the phonon free energy on magnetic states

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npj Computational Materials 2020年第1期6卷 140-146页

作者： Tomonori tanaka Yoshihiro Gohda Department of Materials Science and Engineering Tokyo Institute of TechnologyYokohama 226-8502Japan

Prediction of the Curie temperature is of significant importance for the design of ferromagnetic *** of the most widely used methods to estimate the Curie temperature from first principles relies on a spin Hamiltonian,for example,the Heisenberg Hamiltonian,and exchange coupling parameters obtained by first-principles calculations at zero *** though there have been attempts to include the effects of magnetism on phonons,the influence of magnetism-dependent phonons on magnetism has been disregarded in the theoretical estimation of the Curie ***,we propose a first-principles thermodynamic approach to minimise the total free energy considering both the influences of magnetism on phonons and the feedback effect from phonons to *** applying our scheme to body-centered cubic Fe,we find a significant reduction of the Curie temperature due to the feedback *** result indicates the importance of the feedback effect for a quantitative description of finite-temperature *** addition,we point out that the reduction in the theoretical Curie temperature arises in a wide range of ferromagnetic materials that exhibit phonon softening due to magnetic disordering.

关键词： temperature effect phonon

Structures of Stoichiometric Sodium Oxide Cluster Cations Studied by Ion Mobility Mass Spectrometry

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Chinese Journal of Chemical Physics 2019年第2期32卷 193-199,I0002页

作者： Motoyoshi Nakano Yudai Ishimura Riki Hotta Daiki Hebiguchi toshiaki Nagata Fuminori Misaizu Institute for Excellence in Higher Education Tohoku University 41 Kawauchi Aoba-ku Sendai 980-8576 Japan Department of Chemistry Graduate School of Science Tohoku University 6-3 Aoba Aramaki Aoba-ku Sendai 980-8578 Japan

Structures of stable compositions of sodium oxide cluster cations (NanOm+,n≤11) have been investigated by ion mobility mass spectrometry. Stoichiometric compositions series, Na(Na2O)(n-1)/2^+(n=3, 5, 7, 9, and 11), were observed as stable composition series, and NaO(Na2O)(n-1)/2^+ series (n=5, 7, 9, and 11) were observed as secondary stable series in the mass spectra. To assign the structures of these cluster ion series, collision cross sections between the ions and helium buffer gas were determined experimentally from the ion mobility measurements. Theoretical collision cross sections were also calculated for optimized structures of these compositions. Finally, the structures of Na(Na2O)(n-1)/2^+ and NaO(Na2O)(n-1)/2^+ were assigned to those having similar structural frames for each n except for n=9. All bonds in the assigned structures of Na(Na2O)(n-1)/2^+ were between sodium and oxygen. On the other hand, there was one O-O bond in addition to Na-O bonds in NaO(Na2O)(n-1)/2^+. This result indicates that NaO(Na2O)(n-1)/2^+ have a peroxide ion (O22-) as a substitute for an oxide ion (O2-) of Na(Na2O)(n-1)/2^+. As a result, both stable series, Na(Na2O)(n-1)/2^+ and NaO(Na2O)(n-1)/2^+, are closed-shell compositions. These closed-shell characteristics have a strong influence on the stability of sodium oxide cluster cations.

关键词： Sodium oxide cluster Structure Ion mobility mass spectrometry