記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Elsevier BV  

DOI： 10.1016/s0735-1097(21)01533-3

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：愛媛医学会  

目的:嚥下障害患者が液体を摂取する際、誤嚥の危険性を少なくするため増粘剤を添加することが多い。愛媛大学医学部附属病院では2013年の日本摂食嚥下リハビリテーション学会基準を参考にとろみ早見表を作成しているが、とろみ早見表を用いたとしても適切な粘性選択に難渋することが少なくなかった。今回、院内で使用するとろみ調整食品と飲料についてレオメーターを用いた粘度測定を行い、とろみ早見表の検証を行ったので文献的考察を含めて報告する。方法:とろみ調整食品はトロミナールplus(メディファイン)、飲料はお茶・牛乳・ヤクルトを使用した。とろみ調整食品を用いた3種類の濃度(0.5%、1%、2%)を各飲料でそれぞれ作成した後、3分後と10分後にレオメーター(Anton Paar社製/Physica MCR301)を用いてとろみの粘度測定を行った。測定は20℃にて直径35mm、コーンアングル1°のプレートを用い、ずり速度O.01-100S-1で粘度を測定した。結果:とろみ調整食品を添加した後、全ての飲料は非ニュートン流体へ変化した。10分後、とろみ調整食品0.5%の飲料は薄いとろみの基準を、とろみ調整食品1%の飲料は中間のとろみの基準を満たしていたが、とろみ調整食品2%の飲料は全て濃いとろみの基準外であった。結諭:濃いとろみを作成する際、嚥下調整食分類2013の基準を満たさないことがあるため注意が必要である。(著者抄録)

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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担当区分：筆頭著者,　責任著者   記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：Ovid Technologies (Wolters Kluwer Health)  

Background:

Hemodynamic assessment of untreated nonculprit lesions was not studied in the PROSPECT study (Providing Regional Observations to Study Predictors of Events in the Coronary Tree). We developed a virtual intravascular ultrasound–derived lesion-specific fractional flow reserve (lesion-specific IVUS-FFR) algorithm to assess individual lesion-level FFR. We sought to investigate the relation between lesion-specific IVUS-FFR and major adverse cardiovascular events (MACE) arising from untreated nonculprit lesions in the PROSPECT study.

Methods:

In PROSPECT, 697 patients with acute coronary syndromes underwent 3-vessel grayscale and virtual histology–IVUS to correlate untreated nonculprit plaque morphology with 3-year nonculprit related MACE (composite of cardiac death, cardiac arrest, myocardial infarction, or rehospitalization due to unstable or progressive angina). Lesion-specific IVUS-FFR was calculated from volumetric IVUS lumen area measurements at 0.4 mm intervals by applying a mathematical circulation model using basic fluid dynamics equations.

Results:

Lesion-specific IVUS-FFR was analyzable in 3227 nonculprit lesions in 660 patients among whom 54 nonculprit MACE events (3 myocardial infarctions) occurred at median 3.4-year follow-up. By receiver-operating characteristic analysis, the best cutoff value of lesion-specific IVUS-FFR to predict nonculprit MACE was ≤0.95. After adjusting for patient and lesion characteristics, lesion-specific IVUS-FFR (hazard ratio, 4.83 [95% CI, 2.20–10.61]; P <0.001) was an independent predictor of 3-year nonculprit MACE, in addition to minimum lumen area≤4.0 mm ² , plaque burden ≥70%, and virtual histology thin-cap fibroatheroma.

Conclusions:

Minor reductions in lesion-specific IVUS-FFR were independently associated with future nonculprit MACE arising from untreated angiographically mild stenoses along with previously established high-risk lesion morphological characteristics.

Registration:

URL: https://www.clinicaltrials.gov ; Unique identifier: NCT00180466.

DOI： 10.1161/circinterventions.121.011198

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

BACKGROUND: Fractional flow reserve (FFR) is widely used for the assessment of myocardial ischemia. Intravascular ultrasound (IVUS) is an intracoronary imaging method that provides information about lumen and vessel morphology. Previous studies on the expanded use of IVUS to identify functional ischemia have noted an association between anatomy and physiology, but IVUS-derived minimum lumen area (MLA) has a weak-moderate correlation with myocardial ischemia compared with FFR. We developed a method to calculate FFR using IVUS-derived anatomical information for the assessment of myocardial ischemia. The aims of this study were to investigate the relationship between wire-based FFR and IVUS-derived FFR (IVUS-FFR) and to compare the usefulness of IVUS-FFR and IVUS-derived MLA for functional assessment.Methods and Results:We retrospectively analyzed 50 lesions in 48 patients with coronary stenosis who underwent IVUS and FFR simultaneously. IVUS-FFR was calculated using our original algorithm and fluid dynamics. Mean percent diameter stenosis determined on quantitative coronary angiography and on FFR was 56.4±10.7 and 0.69±0.08, respectively. IVUS-FFR had a stronger linear correlation with FFR (R=0.78, P<0.001; root mean square error, 0.057 FFR units) than with IVUS-derived MLA (R=0.43, P=0.002). CONCLUSIONS: IVUS-FFR may be a more valuable method to identify myocardial ischemia, compared with IVUS-derived MLA.

DOI： 10.1253/circj.CJ-17-1042

PubMed

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：EXCERPTA MEDICA INC-ELSEVIER SCIENCE INC  

Fractional flow reserve (FFR) is widely used for the assessment of myocardial ischemia. Optical coherence tomography (OCT) provides accurate visualization of coronary artery morphology. The aim of this study was to investigate the relation between FFR and OCT-derived FFR. We retrospectively analyzed 31 lesions (25 left anterior descending arteries, 2 left circumflex arteries, and 4 right coronary arteries) in 31 patients with moderate-to severe coronary stenosis, who underwent OCT and FFR measurements simultaneously. OCT-derived FFR was calculated by the original algorithm, which was calculated using the following equation based on fluid dynamics: Delta P = FV + SV2, where V is the flow velocity, F is the coefficient of pressure loss because of viscous friction (Poiseuille resistance), and S is the coefficient of local pressure loss because of abrupt enhancement (flow separation). Mean values of % diameter stenosis by quantitative coronary angiography and FFR were 55.2 +/- 14.0% and 0.70 +/- 0.14, respectively. OCT-derived FFR showed a stronger linear correlation with FFR measurements (r = 0.89, p &lt;0.001; root mean square error = 0.062 FFR units) than quantitative coronary angiography % diameter stenosis (r = 0.65, p &lt;0.001), OCT measurements of minimum lumen area (r = 0.68, p &lt;0.001), and % area stenosis (r = 0.70, p &lt;0.001). OCT-derived FFR has the potential to become an alternative method for the assessment of functional myocardial ischemia, and may elucidate the relation between coronary morphology and FFR. (C) 2017 Elsevier Inc. All rights reserved.

DOI： 10.1016/j.amjcard.2017.07.083

Web of Science

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：EXCERPTA MEDICA INC-ELSEVIER SCIENCE INC  

Fractional flow reserve (FFR) is widely used for the assessment of myocardial ischemia. However, it has the disadvantage of cost and invasive complication risks. We investigated the usefulness of quantitative coronary angiography derived translesional pressure (QCA-TP) for predicting functional myocardial ischemia, using FFR as the gold standard. We retrospectively analyzed 152 coronary narrowings (98 left anterior descending arteries, 28 left circumflex arteries, and 26 right) in 132 patients with mild-severe coronary stenosis who underwent coronary angiography and FFR measurements simultaneously. QCA-TP was calculated using software implemented in the QCA software. Coronary morphology was calculated using both densitometry and lumen edges. Functional myocardial ischemia was defined as an FFR of 0.8 or less. The mean values of diameter stenosis by QCA and FFR were 48.9% +/- 14.9 and 0.76 +/- 0.14, respectively. QCA-TP was significantly correlated with FFR (r = 0.76, p &lt;0.01). The cut-off values of QCA-TP for predicting functional myocardial ischemia based on FFR were 72.8 mm Hg for the left, anterior descending arteries (accuracy, 86.7%; area under the curve [AUC], 0.93), 60.5 mm Hg for the left circumflex arteries (accuracy, 89.3%; AUC, 0.88), and 64.4 mm Hg for the right (accuracy, 88.5%; AUC, 0.94). Therefore, our data suggest that QCA-TP can predict myocardial ischemia with high diagnostic accuracy. (C) 2016 Elsevier Inc. All rights reserved.

DOI： 10.1016/j.amjcard.2016.07.026

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J-GLOBAL

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：OXFORD UNIV PRESS  

Web of Science

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Society of Rheology Japan  

Flow-induced orientational changes in a 0.5 wt % Xanthan gum solution in planar channels with an abrupt expansion were examined by measurement of the flow-induced birefringence and velocity fields. Three kinds of 1:4 abrupt expansion channels with different cross-sectional aspect ratios (of 1, 2, and 5) in the upstream region were tested in the experiments. A similar channel with a different size but the same aspect ratio of 1 was tested for comparison. Remarkable differences were found in the development of flow-induced orientation near the centerline after the abrupt expansion, depending on the aspect ratio. In the cases of the aspect ratios of I and 2, the polymer molecules were temporally aligned perpendicular to the flow direction due to negative elongational flows generated after the abrupt expansion. In contrast, similar phenomena were not observed with an aspect ratio of 5. From these results, the typical flow-induced orientational changes in polymers in the planar channels just after the abrupt expansion were found to be substantially affected by the cross-sectional aspect ratio in the upstream region.

DOI： 10.1678/rheology.44.109

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：The Japan Society of Mechanical Engineers  

Flow-induced orientational changes of an aqueous polymer solution in planer channels have been studied utilizing optical rheometric technics. Two kinds of 1:4 abrupt expansion channels with the same width and different heights of 1 mm and 0.2 mm were tested in the experiments. 0.5 wt% xanthan gum solution was examined as the test fluid with non-Newtonian and viscoelastic properties due to the network structures of the polymer. The optical rheometric device measuring birefringence and orientation angle of the polymer was adapted to a microscope. We have obtained remarkable differences in the development of birefringence between these cases. In the case with channel height of 1 mm, the birefringence measured on the centerline of the channel was rapidly decreased just after the expansion, then showed temporal increase. It is considered that this characteristic change in the birefringence corresponded to the rapid disordering and subsequent alignment of the polymer perpendicular to the flow direction because of the negative elongational flow generated after the expansion. After these regions, the polymer gradually aligned parallel to the flow direction. In contrast, the temporal increase in birefringence and alignment to the transverse direction in molecular orientation was not observed in the case with channel height of 0.2 mm. Flow-induced orientational changes of polymers in planar channels with expansions were considerably affected with the combination of local shear rate and elongational rate changes.

DOI： 10.1299/transjsme.14-00446

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記述言語：英語  

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記述言語：英語  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Institute of Physics Publishing  

The present note describes a method for use in conjunction with a scanning electron microscope (SEM) that has been developed to visualize a liquid flow under a high-level vacuum and to measure a velocity field in a small-scale flow through an open channel. In general, liquid cannot be observed via a SEM, because liquid evaporates under the high-vacuum environment of the SEM. As such, ionic liquid and room temperature molten salt having a vapor pressure of nearly zero is used in the present study. We use ionic liquid containing Au-coated tracer particles to visualize a small-scale flow under a SEM. Furthermore, the velocity distribution in the open channel is obtained by particle tracking velocimetry measurement and a parabolic profile is confirmed. © 2013 IOP Publishing Ltd.

DOI： 10.1088/0957-0233/24/2/027004

Scopus

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記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

Nanofiber aggregation were observed under simple shear, which was generated by rheometer. The rheometer used has parallel plates and cone-and-plates geometries. The Nanofiber (bacteria cellulose fiber) having 50 nm in diameter was extracted from nata de coco and suspended uniformly at 0.5 wt% concentration to glycerin. The torque, which was measured by rheometer, continued to increase with time and did not stay at constant value during 10 minutes of measurement. This is because the nanofibers were formed into wormlike aggregation and it enlarged with time. The diameter of the wormlike aggregation became 1.4 times greater than the length between parallel plates at the end of measurement.

DOI： 10.1299/jsmemecjo.2010.2.0_39

CiNii Books

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担当区分：筆頭著者,　責任著者   記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1299/kikaib.75.753_937

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記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

Secondary vortex enhancement was examined for fiber suspension flows containing bacteria cellulose fiber (BCF) at weight fractions from 0.07 to 0.28 wt%. BCFs were derived from nata de coco. These fluids have non-Newtonian properties even at low weight fraction of BCF. The channel used has a rectangular cross section and an abrupt contraction geometry. As a result, we found that the vortex becomes large as increasing flow rate for BCF suspensions, whereas it becomes small for a Newtonian fluid. The vortex size enhancement is probably caused by the increment of elongational viscosity of test fluid.

DOI： 10.1299/jsmemecjo.2009.2.0_85

CiNii Books

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担当区分：筆頭著者,　責任著者   記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：The Japan Society of Mechanical Engineers  

Flows of polymer solutions through a 3.7:1 abrupt contraction were observed in a micro- and a regular-size channels with rectangular cross sections. The test fluids are three kinds of 0.2 wt% aqueous solutions of polyacrylamide whose rheological properties are different with each other. In the previous works, apparent slips were observed on the channel wall for the polymer solutions and the slip levels of these solutions are considered to be different. In the present paper, the growth of the salient corner vortex is discussed as a function of the shear rate. Consequently, the vortex size in the microchannel is larger than that in the regular-size channel for the flow of polymer solution whose slip level is weak, whereas the vortex size in the microchannel is smaller than that in the regular-size channel for the flow of polymer solution whose slip level is strong.

DOI： 10.1299/jfst.3.987

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担当区分：筆頭著者,　最終著者,　責任著者   記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.4188/jte.53.237

Scopus

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担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：一般社団法人日本機械学会  

Velocity profiles in steady flows of concentrated fluid/particle mixtures through a duct with an abrupt contraction were measured using magnetic resonance imaging (MRI). We used aqueous solutions of carboxymethyl cellulose containing suspended particles at high volume fractions as test fluids. Spheres, short fibers and disk-like particles were added to a suspending medium, respectively. These mixture fluids were not transparent because of high concentration of particle. As a result, a plug-like velocity profile was observed in a straight duct flow for every suspension, but we found that the velocity profile depends on the particle shape at the contraction. Spherical particle did not affect the flow field but short fiber caused a concave shape in the velocity profile near the centerline at upstream region of the contraction. This concave profile becomes obvious with increasing of volume fraction of particle. It is considered that this result is caused by both the migration of short fibers to the low-shear-rate region near the centerline and the larger elongational viscosity of short fiber suspension compared with that of a sphere suspension. Furthermore, the suspension of the disk-like particles caused the unsteady flow at the contraction. This is because the size of particles are widely distributed and the mechanical interaction between particles is very complex.

CiNii Books

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担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：WILEY-V C H VERLAG GMBH  

Velocity profiles in steady flows of fluid/particle mixtures through a duct with an abrupt contraction were measured by magnetic resonance imaging. Aqueous solutions of carboxymethyl cellulose containing particles, including spheres, disk-like particles, and short fibers, at high volume fractions were used. As a result, a plug-like velocity profile was observed in a straight duct flow for every suspension, but the velocity profile depends on the particle shape at contraction. Disk-like particles caused an unsteady flow, and short fibers caused a concave shape in the velocity profile near the centerline upstream of the contraction. Spheres did not affect the flow field. The concave profile became obvious with increased volume fraction of fiber. This result is caused by the larger elongational viscosity of the fiber suspension near the centerline of the channel, as compared with that of the sphere suspension.

DOI： 10.1002/ceat.200700117

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担当区分：筆頭著者,　最終著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

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担当区分：筆頭著者,　責任著者   記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：一般社団法人日本機械学会  

Velocity profiles of concentrated fluid/particle mixtures in tube flows through an abrupt contraction were measured using magnetic resonance imaging (MRI). We used aqueous solutions of carboxymethyl cellulose (CMC) containing suspended particles at high volume fractions as test fluids. The particles used have spherical and slender shapes, respectively. These mixture fluids are opaque because of high concentration of particle. The channel used has a square cross section and an abrupt contraction geometry. As a result, a plug-like velocity profile was observed in the channel flow. Furthermore, we found that the velocity profile depends on the particle shape in the contraction. Spherical particle did not affect the flow field but slender particle caused a concave shape in the velocity profile near the centerline at upstream region of the contraction. This concave profile becomes obvious with increasing of volume fraction of particle. This result is caused by the elongational viscosity distribution of the slender particle suspension at the contraction.

CiNii Books

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担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

The objective of this study is to well understand the migration and orientation of thin micro-particles, such as talc and mica, in a suspension flow through a slit channel as well as to obtain the knowledge of the sheet processing operations of thin micro-particle reinforced composites by means of both experiments and numerical simulations. The following result was obtained in this study: (1) migration of thin micro disk-like particles did not occur in a slit channel flow, thus the concentration distribution was almost uniform: (2) transparent/translucent strand pattern observed in a suspension flow with thin micro disk-like particles was ascribed to the flow-induced shade region produced by disk-like particles, i.e., this phenomenon arises from frequent flip-over of disk-like particles. © 2006 The Textile Machinery Society of Japan.

DOI： 10.4188/jte.52.165

Scopus

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記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

Velocity profiles in concentrated particle suspension flows through a channel were measured using magnetic resonance imaging (MRI). We used non-Newtonian fluids containing suspended particles at high volume fractions. The particles have spherical, slender, and disk-like shapes, respectively. These suspension fluids are opaque. The channel used has a square cross section and an abrupt contraction geometry. As a result, we found that the velocity profile depends on the particle shape in the contraction. Spheres did not affect the flow field but slender and disk-like particles caused a concave shape in the velocity profile.

DOI： 10.1299/jsmemecjo.2006.2.0_33

CiNii Books

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担当区分：筆頭著者,　責任著者   記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1299/kikaic.72.1003

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担当区分：筆頭著者,　最終著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

There are many viscosity equations to describe a shear-thinning viscosity of non-Newtonian fluid. In the present study, a multi-mode viscosity equation to more accurately fit measured data was proposed. The viscosity data were obtained for aqueous solutions of carboxymethylcellulose using a cone-and-plate rheometer. Consequently, the fitted results using the proposed viscosity equation to the measured data were very good. © 2006 The Textile Machinery Society of Japan.

DOI： 10.4188/jte.52.171

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担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：SOC RHEOLOGY, JAPAN  

Velocity profiles of polymer solutions were directly measured in a microchannel with rectangular cross sections. The test fluids are 0.2 wt% aqueous solutions of polyacrylamide whose molecular weights are 6 x 10(6) (fluid A) and 1.5 x 10(7) (fluid B). The microchannel was made of PDMS and it was mounted on the glass plate. The velocity profile in the depth direction is discussed as a function of the flow rate and shear stress on the wall. Consequently, for the flows of fluid A, a symmetric profile is observed in the region between the PDMS wall and the glass wall in a low flow rate, but the velocity profile slightly becomes asymmetric with increasing flow rate: the velocity near the PDMS wall is larger than that near the glass wall. For the flows of fluid 13, a slightly asymmetric profile is observed even in the low flow rate and a largely asymmetric one in the large flow rate. The PDMS wall significantly affects the velocity profile in the flow of polymer solution through a PDMS microchannel.

Web of Science

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担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1002/pc.20129

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担当区分：筆頭著者,　責任著者   記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：一般社団法人 日本繊維機械学会  

The objective of this study is to well understand the migration and orientation of thin micro-particles in a suspension flow by means of both experiments and numerical simulations. In this framework, the evolution of the orientation of thin micro-particles such as talc and mica, which were modeled by a disk-like particle, in a flow through a slit channel was analyzed to obtain the knowledge of the processing operations of thin micro-particle reinforced composites.<br>The thin disk-like particles were subjected by a planar extensional flow in a reservoir, then by a simple shear flow through a slit channel in the experimental apparatus used. The evolution of the orientation of thin disk-like particles was, therefore, studied in both a planar extensional and simple shear flows by numerical calculation of the Jeffery equation: thin disk-like particles aligned in a parallel orientation to upper- and lower-walls of the slit channel in a planar extensional flow through the reservoir, then entered into the inlet of the slit channel. On the other hand, in a simple shear flow through the slit channel, the disk-like particles kept this parallel orientation except the occurrence of a flip-over phenomenon. The period of the flip-over became longer with a decrease in the aspect ratio of the disk-like particles.<br>Furthermore, the measurements of the orientation of the talc particles in a suspension flow through the slit channel clearly showed that almost the same period of the flip-over was found although the particle size was different. These experimental results arise from complex geometries and no accurate data of the thickness of the talc particles.

DOI： 10.4188/transjtmsj.58.t29

CiNii Books

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その他リンク： https://jlc.jst.go.jp/DN/JALC/00248457208?from=CiNii

記述言語：日本語   出版者・発行元：The Visualization Society of Japan  

Axial velocity distribution of a steady tube flow was measured using magnetic resonance imaging (MRI). Test fluids were aqueous solutions of carboxymethyl cellulose (CMC) containing solid particles (glass flake or glass bead) at high volume fractions. As a result, we observed a plug-like velocity distribution in the tube flow. This velocity distribution measured by MRI had a good agreement with that numerically calculated using the viscosity curve of the test fluid. Furthermore the effect of suspended particles on the velocity distribution in the tube flow with an abrupt contraction was also examined. We observed a plug flow for the CMC solution and the bead suspension, but a concave region in the velocity distribution near the centerline at upstream of the contraction for the concentrated flake suspension. This velocity distribution is caused by the shape of the glass flake particle.

DOI： 10.3154/jvs.25.Supplement2_263

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記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

Velocity distribution of a steady pipe flow was measured using magnetic resonance imaging (MRI). Aqueous solutions of carboxymetyl cellulose (CMC) containing dispersed particle (e.g. glass flake, vinylon fiber, etc) were used as test fluids. The test fluids with high volume fraction of particles showed a plug-like velocity profile at high shear rates. The velocity profiles measured by MRI agreed well with those numerically calculated from the viscosity curves. In this research, to examine the effect of disperse particles on the flow field, rectangular channel with a contraction/expansion was also used.

DOI： 10.1299/jsmemecjo.2005.2.0_59

CiNii Books

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記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

Velocity profiles of polymer solutions were directly measured in a microhannel with rectangular cross sections. The test fluids are 0.2 wt% aqueous solutions of polyacrylamide whose molecular weights are 6×10^6 (fluid A) and 1.5×10^7 (fluid B). The microchannel was made of PDMS and it is mounted on the glass plate. The velocity profile in the depth direction is discussed as a function of a shear rate. Consequently, for the flows of fluid A, a symmetric profile is observed in the region between the PDMS wall and the glass wall in a low flow rate, but the velocity profile slightly becomes asymmetric with increasing the shear rate: the velocity near the PDMS wall is larger than that near the glass wall. For the flows of fluid B, a slightly asymmetric profile is observed even in the low flow rate and a largely asymmetric one in the large shear rate. The PDMS wall significantly affects the velocity profile in the flow of polymer solution through a PDMS microchannel.

DOI： 10.1299/jsmemecjo.2005.2.0_37

CiNii Books

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担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：SPRINGER-VERLAG  

Flow-induced fiber orientation and concentration distributions were measured in a concentrated fiber suspension (CFS) and a dilute one (DFS). The channel has a thin slit geometry containing a circular cylinder. In the previous work, many researchers have qualitatively studied fiber orientation and concentration distributions in injection-molded products of fiber-reinforced plastics. In the present work, however, they are quantitatively estimated by direct observation of fibers in the concentrated suspension flow. For the CFS, some fibers rotate in an expansion part between the channel wall and the circular cylinder, and the fiber orientation becomes almost random state. On the other hand, fibers are perfectly aligned along the flow direction owing to the elongational flow near the centerline downstream of the cylinder. The fiber concentration has a flat distribution except near the channel wall and the centerline. For the DFS a minimum in the fiber concentration distribution was clearly observed on the centerline, and two peaks beside the centerline and near the channel wall. This characteristic distribution is caused by the fiber-wall and fiber-cylinder interactions. It is found that the obstacle such as the circular cylinder in the channel significantly affects the fiber orientation downstream of the obstacle for the CFD, while it affects the fiber concentration distribution for the DFS.

DOI： 10.1007/s00397-003-0328-5

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担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：SOC RHEOLOGY, JAPAN  

In the present paper, to elucidate effects of the formation and breakage of filament oil the dip coating process in the Manufacturing of capsules, we measured the filament, length between the tip of the coated rod and the liquid surface when the filament broke, and examined the dependence of the filament length oil the rheological properties of coating liquids and withdrawal velocity to optimize the dip coating process. The coating liquids were aqueous solutions of syrup as Newtonian liquids and mixture liquids of aqueous Solutions of syrup and water-soluble polymer (polyacrylamide) as polymeric liquids. Consequently, it is found that a large withdrawal velocity brings a shorter time at the filament breakage in Newtonian liquids regardless of their shear viscosities. The experimental equation which represents the relation between the breakage length of the filament and the shear viscosity of the coating liquid are presented. In polymeric liquids, a large elongational Viscosity causes a large filament length. The large withdrawal velocity was ineffective upon the reduction of the breakage dine of the filament. The Use of polymeric liquids With large spinnability reduces the efficiency of manufacturing in dip coating process. The normal stress difference of the coating liquid reduces the coating thickness, so that the coating liquid containing polymer is required to have a small spinnability and a moderate normal stress difference.

DOI： 10.1678/rheology.32.85

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記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

In the present paper, we measured the filament length between the tip of the coated rod and the liquid surface when the filament broke in the dip coating process in the manufacturing of capsules, and examined the filament length dependence on the rheological properties of coating liquids and withdrawal velocity. The coating liquids were aqueous solutions of syrup (Newtonian liquids) and mixture liquids of aqueous solutions of syrup and polyacrylamide (polymeric liquids). Consequently, it is found that a large withdrawal velocity brings a shorter time at the filament breakage in Newtonian liquids regardless of their shear viscosities, while a large elongational viscosity causes a large filament length in polymeric liquids. The large withdrawal velocity was ineffective upon the reduction of the breakage time of the filament in polymeric liquids. Therefore, the use of polymeric liquids reduces the efficiency of manufacturing in dip coating process.

DOI： 10.1299/jsmemecjo.2003.2.0_211

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担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

A classical method for visualization of transparent fibers in fiber suspensions using a planar light source is examined by geometrical optics and its defect is revealed. To overcome the defect, a new method using fibers with birefringence is proposed. In the present method the crossed polarizers rotating at a high speed are introduced to observe the fibers with birefringence nearly oriented in the polarizing directions. As a result, the applicability of this method to the visualization of the fibers in a concentrated fiber suspension flow through a slit channel has been confirmed, and its usefulness for the measurement of the fiber orientation and fiber concentration distribution has been demonstrated. Furthermore, our experimental relationship of total shear strain vs. orientation angle in a dilute fiber suspension flow is compared with a theoretical result, and it shows the similar tendency to the theoretical one. © 2002 Published by Elsevier Science Ltd.

DOI： 10.1016/S0020-7225(01)00107-0

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担当区分：筆頭著者,　責任著者   記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：日本繊維機械学会  

DOI： 10.4188/transjtmsj.55.T7

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記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

Orientation and concentration distributions of shore fibers in a concentrated suspension flow through a complex geometry are presented. Fibers are oriented perpendicular to the streamline in an abrupt expansion region. Furthermore fiber orientation distribution is not symmetrical to the channel centerline in downstream region of a L-shaped corner. These orientation states, which are owing to fiber-fiber interaction, are not observed in a dilute fiber suspension flow. Fiber concentration has a flat distribution over a channel width in concentrated suspension, but has a maximum near a channel wall in dilute one.

DOI： 10.1299/jsmemecjo.2002.3.0_41

CiNii Books

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担当区分：筆頭著者,　責任著者   記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1299/kikaic.67.3363

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE BV  

The coupled flow kinematics and fiber orientation distribution were computed to study the development of fiber suspension flows through a parallel plate channel. The effect of fiber-concentration distribution on the flow field was also examined, The suspension used in the computations consisted of high aspect-ratio rigid fibers in a Newtonian fluid. A parabolic velocity profile for a Newtonian flow and an isotropic fiber orientation were taken at the inlet of the channel. Planar orientations of a large number of fibers were evaluated from computation of the Jeffery equation along the streamlines (statistical scheme, the number of fibers N = 180) instead of direct solutions of the Fokker-Plank equation or the evolution equation of the fourth-order orientation tensor with a closure approximation.
For the uniform concentration of fibers, the anisotropic characteristics of fiber orientations and stress field remarkably appear in the region near the inlet. As a result, the flow kinematics for fiber suspensions can change more significantly from the Newtonian counterpart in the region near the inlet as the volume fraction and/or aspect-ratio of fibers increase. When the volume fraction of fibers decreases in the width direction as the channel wall is approached, the velocity profile becomes more plug-like and the anisotropic characteristics more remarkably appear than those fur the uniform concentration case. (C) 2001 Elsevier Science B.V. All rights reserved.

DOI： 10.1016/S0377-0257(01)00118-5

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担当区分：筆頭著者,　責任著者   記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1299/kikaic.67.1689

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担当区分：筆頭著者,　責任著者   記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1299/kikaic.66.2891

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記述言語：日本語   出版者・発行元：The Visualization Society of Japan  

Short fibers in a concentrated fiber suspension are visualized in a high contrast with a suspending fluid. The concentrated fiber suspension becomes transparent by employing an optimal index-of-refraction match of fibers and suspending fluids. Moreover, vinylon fibers as tracers are added to the fiber suspension because vinylon fibers having birefrigence are clearly observed using a transmitted light under crossed nicols.

DOI： 10.3154/jvs.19.Supplement2_59

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担当区分：責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE BV  

Fiber orientation and dispersion in the fiber suspension that flows through a T-shaped branching channel have been experimentally studied. The fiber dispersion is not uniform in a channel flow. In particular, in the suspension containing long fibers, there are no fibers near a wall at a low Reynolds number. However, the content ratio of fibers near the wall increases with an increasing Reynolds number. Fiber orientation angles of short fibers are widely distributed. Furthermore, a variance of orientation angle in the middle region of the channel has a minimum value at a Reynolds number from 10 to 20, and a size of secondary vortex in the branching corner also has a minimum value at a similar Reynolds number. (C) 1997 Elsevier Science B.V.

DOI： 10.1016/S0377-0257(97)00046-3

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担当区分：筆頭著者,　責任著者   記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：日本繊維機械学会  

DOI： 10.4188/transjtmsj.50.5_T131

CiNii Books

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担当区分：筆頭著者,　責任著者   記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.4188/transjtmsj.50.3_T61

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担当区分：最終著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：日本繊維機械学会  

DOI： 10.4188/transjtmsj.49.5_T114

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：日本繊維機械学会  

DOI： 10.4188/transjtmsj.48.5_T121

CiNii Books

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担当区分：筆頭著者,　責任著者   記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：日本繊維機械学会  

DOI： 10.4188/transjtmsj.48.T1

CiNii Books

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

Flow patterns and fiber orientation in the two-dimensional flow of fiber suspension through a contraction or an expansion are calculated numerically using Dinh-Armstrong model. The assumption that fibers lie tangent to a streamline is excluded from the present calculation. Therefore the fiber orientation is obtained by the integration of the Jeffery's equation along a streamline. A vortex near the corner in the suspension flow is different from that of the Newtonian fluid. The dependence of the vortex length on aspect ratio and volume fraction of fiber is discussed. In the contraction flow, fibers lie tangent to a streamline in the main flow region, but not in the vortex region. In the expansion flow, however, fibers rotate along the streamline, hence fibers do not lie tangent to a streamline even in the main flow region. Furthermore, the application of stress relief mechanism is examined for the change of the vortex length.

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担当区分：責任著者   記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.4188/transjtmsj.45.10_T165

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担当区分：責任著者   記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.4188/transjtmsj.45.9_T147

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

Simulation of flow patterns and fibre orientation in the two-dimensional branching flow of fibre suspension is carried out in relation to the production of fibre-reinforced composites. For part I see abstract 93W/01513.

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

The Dinh-Armstrong model is used to measure the flow patterns and fibre orientation in the merging flow of fibre suspensions.

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担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究発表ペーパー・要旨（国際会議）  

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記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

CiNii Books

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記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

Flow-induced orientation changes of 0.5 wt% xanthan gum solution in planar channels have been studied using flow-induced birefringence (FIB) method. Two kinds of 4:1:4 abrupt contraction and a successive abrupt expansion channels with different middle slit length of 1 mm and 10 mm were tested in the experiments. The FIB system was adapted to a microscope. We have obtained remarkable differences in the development of birefringence between these cases. In the case with slit length of 10 mm, the birefringence measured on the centerline of the channel was rapidly decreased just after the expansion, then showed temporal increase. After these regions, the polymer gradually aligned parallel to the flow direction. In contrast, the temporal increase in birefringence and alignment to the transverse direction in molecular orientation was not observed in the case with slit length of 1 mm. Flow-induced orientational change of polymers in planar channels with expansions were considerably affected with slit length in the contracted section.

CiNii Books

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記述言語：英語   掲載種別：研究発表ペーパー・要旨（国際会議）  

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記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

CiNii Books

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記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

CiNii Books

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記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

CiNii Books

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記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

CiNii Books

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開催年月日： 2024年11月

記述言語：日本語   会議種別：口頭発表（一般）  

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開催年月日： 2024年9月

記述言語：日本語   会議種別：ポスター発表  

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開催年月日： 2024年9月

記述言語：日本語   会議種別：ポスター発表  

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開催年月日： 2024年9月

記述言語：日本語   会議種別：ポスター発表  

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開催年月日： 2024年9月

記述言語：日本語   会議種別：ポスター発表  

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記述言語：日本語   会議種別：ポスター発表  

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記述言語：日本語   会議種別：口頭発表（一般）  

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開催年月日： 2024年5月

記述言語：日本語   会議種別：口頭発表（一般）  

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開催年月日： 2023年12月

記述言語：日本語   会議種別：口頭発表（一般）  

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記述言語：日本語   会議種別：口頭発表（一般）  

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記述言語：日本語   会議種別：口頭発表（一般）  

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開催年月日： 2023年10月

記述言語：日本語   会議種別：シンポジウム・ワークショップ パネル（指名）  

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開催年月日： 2023年6月

記述言語：日本語   会議種別：口頭発表（一般）  

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開催年月日： 2023年6月

記述言語：日本語   会議種別：口頭発表（一般）  

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記述言語：日本語   会議種別：口頭発表（一般）  

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記述言語：日本語   会議種別：口頭発表（招待・特別）  

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開催年月日： 2022年12月

記述言語：日本語   会議種別：口頭発表（一般）  

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記述言語：日本語   会議種別：口頭発表（一般）  

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開催年月日： 2022年12月

記述言語：日本語   会議種別：口頭発表（一般）  

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開催年月日： 2022年9月

記述言語：日本語   会議種別：口頭発表（招待・特別）  

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記述言語：日本語   会議種別：口頭発表（一般）  

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開催年月日： 2022年3月

記述言語：日本語   会議種別：口頭発表（招待・特別）  

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開催年月日： 2020年6月

記述言語：日本語   会議種別：口頭発表（一般）  

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開催年月日： 2020年6月

記述言語：日本語   会議種別：口頭発表（一般）  

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開催年月日： 2004年11月

記述言語：日本語  

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開催年月日： 2003年9月

記述言語：日本語  

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開催年月日： 2003年3月

記述言語：日本語  

Orientation and concentration distributions of short fibers in a concentrated suspension flow through a 1 : 16 expansion geometry are presented. In the concentrated suspension fibers are oriented perpendicular to the streamline in an abrupt expansion near the centerline. Furthermore, fiber orientation near the channel wall affects that between the centerline and the wall because of fiber-fiber interaction. In the dilute one, however, these orientation states are not observed. Fiber concentration has a flat distribution over a channel width in the concentrated suspension, but has a maximum due to the fiber-wall interaction near the channel wall in the dilute one.

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記述言語：日本語   会議種別：口頭発表（一般）  

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記述言語：日本語   会議種別：口頭発表（招待・特別）  

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記述言語：日本語   会議種別：口頭発表（一般）  

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記述言語：日本語   会議種別：口頭発表（一般）  

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記述言語：日本語   会議種別：ポスター発表  

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記述言語：日本語   会議種別：口頭発表（一般）  

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記述言語：日本語   会議種別：口頭発表（一般）  

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記述言語：日本語   会議種別：口頭発表（一般）  

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記述言語：日本語   会議種別：口頭発表（一般）  

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記述言語：日本語   会議種別：口頭発表（一般）  

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記述言語：日本語   会議種別：口頭発表（一般）  

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記述言語：日本語   会議種別：口頭発表（一般）  

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記述言語：日本語   会議種別：口頭発表（一般）  

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記述言語：日本語   会議種別：口頭発表（一般）  

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記述言語：日本語   会議種別：口頭発表（一般）  

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記述言語：日本語   会議種別：口頭発表（一般）  

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記述言語：日本語   会議種別：口頭発表（一般）  

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記述言語：日本語   会議種別：口頭発表（一般）  

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記述言語：日本語   会議種別：口頭発表（一般）  

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記述言語：日本語   会議種別：口頭発表（一般）  

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記述言語：日本語   会議種別：口頭発表（一般）  

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記述言語：日本語   会議種別：口頭発表（一般）  

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記述言語：日本語   会議種別：口頭発表（一般）  

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記述言語：日本語   会議種別：口頭発表（一般）  

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記述言語：日本語   会議種別：シンポジウム・ワークショップ パネル（指名）  

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記述言語：日本語   会議種別：公開講演，セミナー，チュートリアル，講習，講義等  

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記述言語：日本語   会議種別：口頭発表（一般）  

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記述言語：日本語   会議種別：口頭発表（一般）  

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記述言語：日本語   会議種別：公開講演，セミナー，チュートリアル，講習，講義等  

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記述言語：日本語   会議種別：口頭発表（一般）  

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記述言語：日本語   会議種別：口頭発表（一般）  

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記述言語：日本語   会議種別：口頭発表（一般）  

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記述言語：日本語   会議種別：口頭発表（一般）  

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記述言語：日本語   会議種別：口頭発表（一般）  

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記述言語：英語   会議種別：口頭発表（一般）  

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記述言語：日本語   会議種別：口頭発表（招待・特別）  

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記述言語：英語   会議種別：口頭発表（招待・特別）  

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記述言語：日本語   会議種別：口頭発表（一般）  

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記述言語：日本語   会議種別：口頭発表（一般）  

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記述言語：日本語   会議種別：口頭発表（招待・特別）  

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記述言語：日本語   会議種別：口頭発表（招待・特別）  

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記述言語：日本語   会議種別：シンポジウム・ワークショップ パネル（指名）  

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記述言語：日本語   会議種別：口頭発表（一般）  

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記述言語：日本語   会議種別：口頭発表（一般）  

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記述言語：日本語   会議種別：口頭発表（一般）  

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記述言語：日本語   会議種別：口頭発表（一般）  

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種別：会誌・広報誌

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執筆者：本人 

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執筆者：本人 

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