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Journal of Materials Science & Technology 2020年第1期36卷 106-117页

作者： Mulin Liu Naoki Takata asuka suzuki Makoto Kobashi Department of Materials Process Engineering Graduate School of EngineeringNagoya UniversityFuro-choChikusa-kuNagoya464-8603Japan

To identify the microstructural features of the lattice structures of Al alloys built via the selective laser melting(SLM)process,AlSil OMg alloy with a body-centered cubic(BCC)-type lattice structure was *** microstructures comprising melt pools with several columnarα-Al phases withorientations along the elongation direction and surrounded by eutectic Si particles were observed at all portions of the built lattice *** the node portions of the lattice structure,a gradient microstructure(continuous change in microstructure)was *** columnarα-Al phases were observed near the top surface of the node portion,whereas they became coarser and more equiaxed near the bottom surface,resulting in softening localized near the bottom *** the strut portions of the lattice structure,the columnarα-Al phases were elongated along the inclined direction of *** trend was more prevalent near the bottom ***α-Al phases became coarser and more equiaxed near the bottom surface as *** aforementioned results were the basis of a discussion of the development of the gradient microstructure in lattice-structured Al alloys during the SLM process in terms of thermal conductivities at the boundaries between the manufactured(locally melted and rapidly solidified)portions and adjacent(unmelted)alloy powder.

关键词： Additive manufacturing Lattice structure Aluminum alloy Microstructure Thermal conductivity

Change in microstructural characteristics of laser powder bed fused Al–Fe binary alloy at elevated temperature

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Journal of Materials Science & Technology 2022年第2期97卷 38-53页

作者： Xing Qi Naoki Takata asuka suzuki Makoto Kobashi Masaki Kato Department of Materials Process Engineering Graduate School of EngineeringNagoya UniversityFuro-choChikusa-kuNagoya 464-8603Japan Aichi Center for Industry and Science Technology 1267-1 AkiaiYakusa-choToyota 470-0356Japan

The present study addressed the change in the microstructure of Al-2.5 wt%Fe binary alloy produced using laser powder bed fusion(L-PBF)technique by thermal exposure at 300℃,and the associated mechanical and thermal properties were systematically examined as ***-semi-cylindrical patterns corresponding to melt pools in the microstructure were macroscopically observed for the asmanufactured *** change in the melt-pool morphology was observed after thermal exposure for1000 *** the melt pools,a large number of the nanoscale metastable Al6 Fe phase particles were uniformly distributed inside columnar grains of theα-Al matrix containing concentrated solute Fe in *** sequential formation and coarsening of stableθ-Al13 Fe4 phases were observed upon exposure to a 300℃ environment,but a considerable amount of nano-sized metastable Al6 Fe phases remained even after 1000 ***,the thermal exposure continuously reduced the concentration of solute Fe atoms in theα-Al *** significant grain growth was found inα-Al matrix after 1000 h owing to the pinning effect of the dispersed fine particles on grain boundary *** results demonstrate a sluggish change in microstructural morphologies of the Al-2.5 wt%Fe *** quantified microstructural parameters addressed dominant strengthening contributions by the solid solution of Fe element and Orowan strengthening mechanism by fine Al-Fe intermetallics in the L-PBF-produced *** high strength level was sustained even after being exposed to 300℃ for long *** superior balance of mechanical properties and thermal conductivity can be achieved in the experimental alloys by taking advantage of the various microstructural parameters related to the Al-Fe intermetallic phases andα-Al matrix.

关键词： Al-Fe alloy Laser powder bed fusion Phase transformation Microstructure Tensile properties

Microstructural origins of high strength of Al-Si alloy manufactured by laser powder bed fusion:In-situ synchrotron radiation X-ray diffraction approach

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Journal of Materials Science & Technology 2024年第11期178卷 80-89页

作者： Naoki Takata Mulin Liu Masahiro Hirata asuka suzuki Makoto Kobashi Masaki Kato Hiroki Adachi Department of Materials Process Engineering Graduate School of EngineeringNagoya UniversityFuro-choChikusa-kuNagoya 464-8603 Japan Graduate School of Engineering University of HyogoHimeji 671-2280Japan Aichi Center for Industry and Science Technology 1267-1 AkiaiYakusa-choToyota 470-0356 Japan

The microstructural factors contributing to the high strength of additive-manufactured Al-Si alloys us-ing laser-beam powder bed fusion(PBF-LB)were identified by in-situ synchrotron X-ray diffraction in tensile deformation and transmission electron ***-LB and heat treatment were employed to manufacture Al-12%Si binary alloy specimens with different *** an early stage of de-formation prior to macroscopic yielding,stress was dominantly partitioned into the α-Al matrix,rather than the Si phase in all *** concentrated Si solute(~3%)in the α-Al matrix promoted the dynamic precipitation of nanoscale Si phase during loading,thereby increasing the yield *** macroscopic yielding,the partitioned stress in the Si phase monotonically increased in the strain-hardening regime with an increase in the dislocation density in the α-Al *** a later stage of strain hardening,the flow curves of the partitioned stress in the Si phase yielded stress relaxation owing to plastic ***,Si-phase particles localized along the cell walls in the cellular-solidified microstructure play a significant role in dislocation obstacles for strain *** with the results of the heat-treated specimens with different microstructural factors,the dominant strengthening factors of PBF-LB manufactured Al-Si alloys were discussed.

关键词： Laser powder bed fusion Aluminum alloys Microstructures X-ray diffraction(XRD) Strain hardening

Therapeutic potential of stem cells in subarachnoid hemorrhage

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Neural Regeneration Research 2025年第4期20卷 936-945页

作者： Hideki Kanamaru Hidenori suzuki Department of Neurosurgery Mie University Graduate School of MedicineTsuJapan

Aneurysm rupture can result in subarachnoid hemorrhage,a condition with potentially severe consequences,such as disability and *** the acute stage,early brain injury manifests as intracranial pressure elevation,global cerebral ischemia,acute hydrocephalus,and direct blood–brain contact due to aneurysm *** may subsequently cause delayed cerebral infarction,often with cerebral vasospasm,significantly affecting patient *** complications such as brain volume loss and chronic hydrocephalus can further impact *** the mechanisms of subarachnoid hemorrhage-induced brain injury is paramount for identifying effective *** cell therapy,with its multipotent differentiation capacity and anti-inflammatory effects,has emerged as a promising approach for treating previously deemed incurable *** review focuses on the potential application of stem cells in subarachnoid hemorrhage pathology and explores their role in neurogenesis and as a therapeutic intervention in preclinical and clinical subarachnoid hemorrhage studies.

关键词： delayed cerebral ischemia early brain injury matricellular protein neurogenesis stem cell therapy subarachnoid hemorrhage

Stage IV malignant transformation of mature cystic teratoma palliatively treated with concurrent chemoradiotherapy:A case report

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World Journal of Clinical Cases 2025年第1期13卷 56-61页

作者： Saori Kondo Takashi suzuki Kanato Yoshiike Sakura Yamanaka Kenta Sonehara Hiroshi Nabeshima Osamu Oguchi Department of Obstetrics and Gynecology Saku Central Hospital Advanced Care CenterSaku City 385-0051NaganoJapan

BACKGROUND Malignant transformation(MT)of mature cystic teratoma(MCT)has a poor prognosis,especially in advanced *** chemoradiotherapy(CCRT)has an inhibitory effect on *** SUMMARY Herein,we present a case in which CCRT had a reduction effect preoperatively.A 73-year-old woman with pyelonephritis was referred to our *** tomography revealed right hydronephrosis and a 6-cm pelvic *** ultrasound-guided fine-needle biopsy(EUS-FNB)revealed squamous cell *** patient was diagnosed with MT of *** to her poor general con-dition and renal malfunction,we selected CCRT,expecting fewer adverse *** CCRT,her performance status improved,and the tumor size was reduced;surgery was *** months postoperatively,the patient developed dis-semination and lymph node *** chemotherapy was *** died 18 months after treatment *** EUS-FNB was useful in the diagnosis of MT of MCT;CCRT suppressed the disea-se and improved quality of life.

关键词： Mature cystic teratoma Malignant transformation Squamous cell carcinoma Concurrent chemoradiotherapy Endoscopic ultrasound-guided fine-needle biopsy Case report

Long-term follow-up of ulcerative colitis patients treated on the basis of their cytomegalovirus antigen status

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World Journal of Gastroenterology 2014年第2期20卷 509-517页

作者： Toshihiro Inokuchi Jun Kato Sakiko Hiraoka Hideyuki suzuki asuka Nakarai Tomoko Hirakawa Mitsuhiro Akita Sakuma Takahashi Keita Harada Hiroyuki Okada Kazuhide Yamamoto Department of Gastroenterology and Hepatology Okayama University Graduate School of MedicineDentistry and Pharmaceutical SciencesOkayama 700-8558Japan Second Department of Internal Medicine Wakayama Medical UniversityWakayama 641-0012Japan

AIM:To clarify the impact of cytomegalovirus(CMV)activation and antiviral therapy based on CMV antigen status on the long-term clinical course of ulcerative colitis(UC)***:UC patients with flare-up were divided into CMV-positive and-negative groups according to the CMV antigenemia *** main treatment strategy provided for the patients in the CMV-positive group comprised a dose reduction of corticosteroids and administration of ***:The median number of days to initial remission was significantly greater for the patients in the CMV-positive group(21 d vs 16 d,P=0.009).However,the relapse rate after remission and colectomy rate during more than 30 mo of observation did not differ between the two *** analysis revealed that administration of ganciclovir was the only independent factor for avoiding colectomy in patients of the CMV-positive ***:CMV antigen status did not significantly affect the long-term prognosis in UC patients under treatment with appropriate antiviral therapy.

关键词： Ulcerative colitis Cytomegalovirus Cytomegalovirus antigenemia assay

Design Method of Guide Vane for Wells Turbine

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Journal of Thermal Science 2006年第2期15卷 126-131页

作者： Masami suzuki Department of Mechanical Engineering Graduate School of Engineering The University of Tokyo

Guide vanes are installed in the Wells turbine in order to improve its efficiency, self-rotating characteristics and off design performance with stall. This work attempts to explain the role of these guide vanes on the basis of momentum theory. It is shown that the upstream vanes are more effective in enhancing efficiency than the downstream ones. A design method for guide vanes is suggested based on experimental data and potential theory. Experimental studies carried out by the author confirm the theory proposed.

关键词： wells turbine guide vane cascade potential flow wave energy converter ocean engineering

Magnetic properties of soft layer/FePt-MgO exchange coupled composite perpendicular recording media

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Chinese Physics B 2008年第10期17卷 3907-3909页

作者：阴津华 Takao suzuki 潘礼庆 Department of Physics University of Science and Technology Beijing Information Storage Materials Laboratory Toyota Technological Institute

The magnetic properties of exchange coupled composite （ECC） media that are composed of perpendicular magnetic recording media FePt MgO and two kinds of soft layers have been studied by using an x-ray diffractometer, a polar Kerr magneto-optical system （PMOKE） and a vibrating sample magnetometer （VSM）. The results show that ECC media can reduce the coercivities of perpendicular magnetic recording media FePt-MgO. The ECC media with granular-type soft layers have weaker exchange couplings between magnetic grains and the magnetization process, for ECC media of this kind mainly follow the Stoner Wohlfarth model.

关键词： exchange coupled composite media perpendicular magnetic recording media magnetic properties

Uncertainty in solid precipitation and snow depth prediction for Siberia using the Noah and Noah-MP land surface models

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Frontiers of Earth Science 2018年第4期12卷 672-682页

作者： Kazuyoshi suzuki Milija ZUPANSKI Institute of Arctic Climate and Environment Change Research (IACE) Japan Agency for Marine-Earth Science and Technology (JAMSTEC)Yokohama236-0001Japan Cooperative Institute for Research in the Atmosphere Colorado State UniversityFort CollinsCO 80523-1375USA

In this study, we investigate the uncertainties associated with land surface processes in an ensemble predication context. Specifically, we compare the uncertainties produced by a coupled atmosphere-land modeling system with two different land surface models, the Noah- MP land surface model (LSM) and the Noah LSM, by using the Maximum Likelihood Ensemble Filter (MLEF) data assimilation system as a platform for ensemble prediction. We carried out 24-hour prediction simulations in Siberia with 32 ensemble members beginning at 00:00 UTC on 5 March 2013. We then compared the model prediction uncertainty of snow depth and solid precipitation with observation-based research products and evaluated the standard deviation of the ensemble spread. The prediction skill and ensemble spread exhibited high positive correlation for both LSMs, indicating a realistic uncertainty estimation. The inclusion of a multiple snowlayer model in the Noah-MP LSM was beneficial for reducing the uncertainties of snow depth and snow depth change compared to the Noah LSM, but the uncertainty in daily solid precipitation showed minimal difference between the two LSMs. The impact of LSM choice in reducing temperature uncertainty was limited to surface layers of the atmosphere. In summary, we found that the more sophisticated Noah-MP LSM reduces uncertainties associated with land surface processes compared to the Noah LSM. Thus, using prediction models with improved skill implies improved predictability and greater certainty of prediction.

关键词： ensemble simulation land-atmosphere interaction ensemble spread vertical temperature snow prediction

A Partial Order in the Knot Table Ⅱ

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Acta Mathematica Sinica,English Series 2008年第11期24卷 1801-1816页

作者： Teruaki KITANO Masaaki suzuki Department of Information Systems Science Faculty of Engineering Soka University 1-236 Tangi-cho Hachioji-city Tokyo 192-8577 Japan Department of Mathematics Akita University 1-1 Tegata-Gakuenmachi Akita 010-8502 Japan

A partial order on the set of the prime knots can be defined by the existence of a surjective homomorphism between knot groups. In the previous paper, we determined the partial order in the knot table. In this paper, we prove that 31 and 41 are minimal elements. Further, we study which surjection a pair of a periodic knot and its quotient knot induces, and which surjection a degree one map can induce.

关键词： knot partial order surjective homomorphism period degree one map