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拉伸指数模型扩散加权成像与单指数、双指数模型对肝脏局灶性病变鉴别诊断价值的比较研究

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国际医学放射学杂志 2019年第6期 748-748页

作者： H.C.Kim n.seo Y.E.Chung M.S.Park J.Y.Choi M.J.Kim 张凯 Department of Radiology Severance Hospital Yonsei University College of Medicine

摘要目的比较单指数、双指数及拉伸指数模型扩散加权成像(DWI)对肝脏局灶性病变(FLL)的鉴别诊断价值。材料与方法回顾性分析180例行3.0 T MR检查的FLL病人

关键词：拉伸指数模型肝脏局灶性病变双指数模型扩散加权成像鉴别诊断价值比较研究

Intensive-visible-light-responsive AnbO_(2)n(A = Sr, Ba) synthesized from layered perovskite A_(5)nb_(4)O_(15) for enhanced photoelectrochemical water splitting

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Journal of Energy Chemistry 2022年第5期31卷 529-537页

作者： Sukanya Ramaraj Jeongsuk seo Departmentof Chemistry.College of natural Sciences Chonnam national University.77 Yongbong-ro Buk-gu Gwangju 61186Republicof Korea

nb-based, perovskite-type oxynitrides Anb(O,n)_(3)(A = Sr, Ba) have been significantly attractive semiconductor materials for photoelectrochemical(PEC) water splitting due to their absorption abilities of intensive-visible-light. However, PEC activities of these perovskites are relatively low due to reduction of nb species during nitridation leading to the generation of anion defects and impurity ***, we propose nitridation of A-rich, layered perovskite A_(5)nb_(4)O_(15) as starting oxides for general synthesis of photoactive AnbO_(2)n. These layered perovskite A_(5)nb_(4)O_(15) were completely transformed to single phase perovskite-type AnbO_(2)n by nitridation. Wavelength onsets of light absorption were observed at 700 nm for SrnbO_(2)n and at 740 nm for BanbO_(2)n. According to X-ray photoelectron spectroscopy results,excess Lewis base A species significantly suppressed the generation of reduced species such as nb^(4+) and nb^(3+)during nitridation, although it led to an amorphous surface of the as-prepared *** annealing in Ar largely enhanced surface crystallinity of AnbO_(2)n. As a result, Co(OH)_(x)/AnbO_(2)n/FTO photoanodes, prepared by loading Co(OH)_(x) electrocatalyst, showed high photocurrent density of 1.6(A = Sr) and 2.4 m A cm^(-2)(A = Ba) at 1.23 VRHEunder AM 1.5 G simulated sunlight. These results demonstrate that A-rich layered perovskite A_(5)nb_(4)O_(15)are effective starting precursors for preparing lowdefective AnbO_(2)n, thus improving PEC water splitting activity.

关键词： Perovskite-type oxynitride CanbO_(2)n SrnbO_(2)n BanbO_(2)n A-rich starting oxide Surface heat treatment Ar annealing Solar water oxidation

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评估CT和MRI判断IPMn良恶性的价值

肝胆外科杂志 2015年第2期23卷 84-84页

作者： seo n Byun JH Kim JH 年建泽耿小平

背景胰腺导管内乳头状黏液瘤（IPMn）是由胰腺导管内产生黏液的上皮细胞呈乳头状增殖形成的肿瘤,该肿瘤具有癌变的风险且肿瘤的治疗与IPMn性质密切相关,因此IPMn恶变预测尤为重要,目前尚缺乏研究计算机断层扫描（CT）和磁共振成像（MRI... 详细信息

背景胰腺导管内乳头状黏液瘤（IPMn）是由胰腺导管内产生黏液的上皮细胞呈乳头状增殖形成的肿瘤,该肿瘤具有癌变的风险且肿瘤的治疗与IPMn性质密切相关,因此IPMn恶变预测尤为重要,目前尚缺乏研究计算机断层扫描（CT）和磁共振成像（MRI）在IPMn诊断中价值。方法 2011年9月到2013年9月韩国蔚山大学医学收治经病理证实IPMn280例,

关键词：胰腺导管磁共振成像黏液瘤壁结节 CT IPMn MRI 蔚山治经主胰管

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Effect of internal sloshing on added resistance of ship

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Journal of Hydrodynamics 2017年第1期29卷 13-26页

作者： Min-Guk seo Yonghwan Kim Dong-Min Park Korea Research Institute of Ships and Ocean Engineering DaejeonKorea Department of naval Architecture and Ocean Engineering Seoul National UniversitySeoulKorea

The motion responses of ships carrying liquid cargo are affected not only by external wave excitation, but also by internal sloshing-induced forces and moments. Sloshing flow is coupled with the ship motion. This means the added resistance in waves may change when sloshing occurs inside the tank of the ship. In this study, the motion responses and added resistance of a ship, coupled with the sloshing-induced internal forces and moments are considered by using the linear potential theory. The three-dimensional Rankine panel method, in which the physical quantities are represented by using B-spline basis function, is applied. The sloshing flow of inner tanks is also simulated by Using the Rankine panel method and linearized boundary value problem. To study the added resistance, a near-field method, which integrates the second-order pressure on a body surface, is applied. The model ship is a blunt modified Wigley model with two inner tanks. numerical results obtained without inner tanks are compared with the experimental data, and then the effect of filling ratio of inner tanks on ship motion and added resistance are observed. The components that induce added resistance are examined, and the effects of surge motion on sloshing flow and added resistance are briefly considered. This study shows that the sloshing flow inside the inner tanks may significantly influence not only the motion responses, but also added resistance, especially, when the incident wave frequency approaches the resonance frequency of the sloshing flow.

关键词： Added resistance sloshing seakeeping coupled effect Rankine panel method

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Two-dimensional perovskite SrnbO_(2) n with Zr doping for accelerating photoelectrochemical water splitting

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Journal of Materials Science & Technology 2023年第11期142卷 176-184页

作者： Thanh Tam Thi Tran Van-Huy Trinh Jeongsuk seo Department of Chemistry College of Natural SciencesChonnam National University77 Yongbong-roBuk-guGwangju 61186South Korea

The superior ability of perovskite-type SrnbO_(2) n to absorb intensive visible light makes it a potential semiconductor to produce hydrogen and oxygen by photoelectrochemical(PEC)water splitting under *** surface morphologies,such as shape and structure,of the oxynitride strongly affect its photoactivity,although the mechanism has been hardly ***,we report a two-dimensional(2D)porous SrnbO_(2) n plate with Zr doping,nitrided from layered perovskite Sr_(5)nb_(4)O_(15) and also its largely enhanced PEC water splitting ***^(4+)was doped in Sr_(5)nb_(4)O_(15) during flux-assisted calcination using KCl,producing 2D-type truncated-octahedral Sr_(5)nb_(4)O_(15):Zr plates approximately 50 nm in *** nitridation completely transformed Sr_(5)nb_(4)O_(15):Zr to 2D single-crystalline SrnbO_(2) n:Zr with a large surface area,which was subsequently used to fabricate a thin and uniform photoanode by the spin coating *** a result,the Co(OH)_(x)/SrnbO_(2) n:Zr/FTO photoanode capable of absorbing visible light of up to 680 nm exhibited an activity of 2.0 mA cm^(-2) at 1.23 V vs the reversible hydrogen electrode for water splitting under AM 1.5G simulated *** improvement in photoactivity mainly originated from the 2D surface morphology of SrnbO_(2) n:Zr,which is clearly distinguishable from 3D-type *** to electrochemical analyses,the 2D structure of SrnbO_(2) n:Zr boosted the separation and accelerated the transfer of charges photogenerated during the water splitting,thus driving the reaction ***,the result empirically demonstrates that controlling the surface morphology of SrnbO_(2) n is an effective strategy to suppress the recombination of charges and minimize their diffusion pathway,eventually enhancing the PEC activity.

关键词： Solar water splitting Water oxidation BanbO_(2)n Doping engineering Flux-assisted calcination Spin coating

Investigation of Punch Resistance of the Allomyrira dichtoloma Beetle Forewing

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Journal of Bionic Engineering 2018年第1期15卷 57-68页

作者： ngoc San Ha Vinh Tung Le nam seo Goo Smart Microsystem Research Laboratory Department of Advanced Technology Fusion Division of Interdisciplinary Studies Konkuk University Seou105029 Republic of Korea Faculty of Science Engineering and Technology Swinburne University of Technology Hawthorn VIC 3122 Australia

In this study, the punch resistance of the beetle forewing was investigated to address the ability of the forewing against the external force. The punch resistance of the forewing was measured for different sizes and sexes of beetles using a conventional testing method in conjunction with the Digital Image Correlation （DIC） technique. The results showed that the maximum fracture load was measured around 23 n for the female beetle and around 20.2 n for the male beetle in the front-side punch test. Moreover, the fracture load in the front-side punch test was higher than that in the back-side punch test for both male and female beetles. This means that the beetle forewing plays a protection role against external loads. Furthermore, the puncture energy in the front-side punch test for the female beetle （6.91 m J） was a little higher than that for the male beetle （5.27 mJ）. In addition, the DIC results revealed that the first crack occurred along the trachea line and the second crack then appeared in the direction that was perpendicular to the direction of the first crack. This study provides a com- prehensive understanding of the mechanical protection properties of the beetle forewing and offers a good lesson for studying lightweight bio-inspired composite material.

关键词： beetle forewing punch test punch energy digital image correlation