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Rare Metals 2020年第8期39卷 918-927页

作者： Si-Jun Park Kyu-Hyuk Lee Seong-Moon Seo Hi-Won Jeong young-soo Yoo HeeJin Jang Multi-Material Research Center Gwangju-Jeonnam DivisionKorea Automotive Technology InstituteGwangju 62207Republic of Korea Department of Advanced Materials Engineering Chosun UniversityGwangju 61452Republic of Korea High Temperature Materials Group Korea Institute of Materials ScienceChangwon 51508Republic of Korea Department of Materials Science and Engineering Chosun UniversityGwangju 61452Republic of Korea

The effects of alloying elements(Co,Cr,Mo,W,Al,Ti,and Ta)on the oxidation resistance of Ni-(0-15)Co-(8-15)Cr-(0-5)Mo-(0-10)W-(3-8)Al-(0-5)Ti-(0-10)Ta-0.1 C-0.01 B alloys were *** sample compositions were designed by the Box-Behnken method of design of experiments(DOE).The alloying elements show complicated effects on the mass gain due to oxidation,depending on the alloy *** reduces the mass gain *** other elements except Al do not appear to exert a strong effect on the oxidation rate on average,but their influences are shown clearly in the alloys with a low Al ***,W,and Ta reduce the oxidation rate,while Cr,Mo,and Ti promote *** is the most effective element in reducing the oxidation rate of the alloy with a low Al *** is confirmed that a continuous Al2O3 layer is essentially required for high oxidation *** oxide scale of easily oxidized alloys has various oxides such as NiCr2O4,NiAl2O4,NiO,Cr2O3,CrTaO4,and TiO2.

关键词： High temperature oxidation Alloy composition Ni-based superalloy Oxidation resistance Design of experiments

Formation of intermetallic compound at interface between rare earth elements and ferritic-martensitic steel by fuel cladding chemical interaction

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Journal of Rare Earths 2012年第6期30卷 599-603页

作者： Jun Hwan Kim Byoung Oon Lee Chan Bock Lee Seung Hyun Jee young soo Yoon Advanced Fuel Development Division Korea Atomic Energy Research InstituteP.O.Box 105YuseongDaejeon305-600Republic of Korea Department of Mate-rials Science and Engineering Yonsei University134 Sinchon DongSeoul120-749Republic of Korea

The intermetallic compounds formation at interface between rare earth elements and clad material were investigated to demonstrate the effects of rare earth elements on fuel-cladding chemical interaction （FCCI） behavior. Mischmetal （70Ce-30La） and Nd were prepared as rare earth elements. Diffusion couple testing was performed on the rare earth elements and cladding （9Cr2W steel） near the operation temperature of （sodium-cooled fast reactor） SFR fuel. The performance of a diffusion barrier consisting of Zr and V metallic foil against the rare earth elements was also evaluated. Our results showed that Ce and Nd in the rare earth elements and Fe in the clad material interdiffused and reacted to form intermetallic species according to the parabolic rate law, describing the migration of the rare earth element. The diffusion of Fe limited the reaction progress such that the entire process was governed by the cubic rate law. Rare earth materials could be used as a surrogate for high burnup metallic fuels, and the performance of the barrier material was demonstrated to be effective.

关键词： intermetallic compound sodium-cooled fast reactor (SFR) metallic fuel fuel-cladding chemical interaction (FCCI) rare earths Barrier

Comparison of the Bright Band Characteristics Measured by Micro Rain Radar (MRR) at a Mountain and a Coastal Site in South Korea

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Advances in Atmospheric Sciences 2009年第2期26卷 211-221页

作者： Joo-Wan CHA Ki-Ho CHANG Seong soo YUM young-Jean CHOI Department of Atmospheric Sciences Yonsei University Global Environment System Research Laboratory NIMR/KMA

Data from a long term measurement of Micro Rain Radar （MRR） at a mountain site （Daegwallyeong, DG, one year period of 2005） and a coastal site （Haenam, HN, three years 2004-2006） in South Korea were analyzed to compare the MRR measured bright band characteristics of stratiform precipitation at the two sites. On average, the bright band was somewhat thicker and the sharpness （average gradient of reflectivity above and below the reflectivity peak） was slightly weaker at DG, compared to those values at HN. The peak reflectivity itself was twice as strong and the relative location of the peak reflectivity within the bright band was higher at HN than at DG. Importantly, the variability of these values was much larger at HN than at DG. The key parameter to cause these differences is suggested to be the difference of the snow particle densities at the two sites, which is related to the degree of riming. Therefore, it is speculated that the cloud microphysical processes at HN may have varied significantly from un-rimed snow growth, producing low density snow particles, to the riming of higher density particles, while snow particle growth at DG was more consistently affected by the riming process, and therefore high density snow particles. Forced uplifting of cloudy air over the mountain area around DG might have resulted in an orographic supercooling effect that led to the enhanced riming of supercooled cloud drops.

关键词： Micro Rain Radar bright band thickness and sharpness cloud microphysical processes local characteristics

Expression of Ki-67,p53,and K-ras in chronic pancreatitis and pancreatic ductal adenocarcinoma

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World Journal of Gastroenterology 2005年第43期11卷 6765-6769页

作者： Seok Jeong Don Haeng Lee Jung Il Lee Jin-Woo Lee Kye sook Kwon Pum-soo Kim Hyung Gil Kim Yong Woon Shin young soo Kim young Bae Kim Division of Gastroenterology Department of Pathology

AIM： To examine surgical specimens of pancreas with either chronic pancreatitis or pancreatic cancer in order to study whether ductal hyperplasia and dysplasia in pancreas represent precursor lesions for pancreatic cancer. METHODS： We examined expression of Ki-67, CEA, p53, and K-ras, in the surgical specimens of pancreas with adenocarcinomas （n = 11） and chronic pancreatitis （n = 12）. Cellular proliferation was assessed by Ki-67 proliferation index using the proliferation marker Ki-67. In specimens with pancreas cancer, we divided pancreas epithelium into normal （n = 7）, ductal hyperplasia （n = 3）, dysplasia （n = 4）, and cancerous lesion （n = 11） after hematoxylin and eosin staining, Ki-67, and CEA immunohistochemical staining. In cases with chronic pancreatitis, the specimen was pathologically examined as in cases with pancreas cancer, and they were also determined as normal （n = 10）, ductal hyperplasia （n = 4）, or dysplasia （n = 5）. p53 and K-ras expression were also studied by immunohistochemical staining. RESULTS： In pancreatic cancer, the Ki-67 index was 3.73±3.58 in normal site, 6.62±4.39 in ductal hyperplasia, 13.47：1：4.02 in dysplasia and 37.03±10.05 in cancer tissue, respectively. Overall, p53 was positive in normal ducts, ductal hyperplasia, dysplasia, and carcinoma cells in 0 of 14 （0%）, 0 of 7 （0%）, 7 of 9 （78%）, and 10 of 11 （91%）, respectively, and K-ras was positive in 0 of 8 （0%）, 1 of 3 （33%）, 4 of 6 （67%）, 4 of 5 （80%）, respectively. CONCLUSION： Our results favorably support the hypothesis that ductal hyperplasia and dysplasia of the pancreas might be precursor lesions for pancreas cancer. Further evaluation of oncogenes by the molecular study is needed.

关键词： Ki-67 p53 K-ras Chronic pancreatitis Pancreatic ductal adenocarcinoma

Effect of incision types for Artisan phakic intraocular lens implantation on ocular higher order aberrations

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International Journal of Ophthalmology(English edition) 2016年第12期9卷 1785-1789页

作者： young Min Park Bong Joon Choi Jong soo Lee Department of Ophthalmology Gyeongsang National University School of Medicine Gyeongsang National University Changwon Hospital 11 Samjeongja-ro Seongsan-gu Changwon-si Gyeongsangnam-do 51472 Korea Lee Eye Clinic Pusan 47524 Korea Department of Ophthalmology School of Medicine Pusan National University and Medical Research Institute Pusan National University Hospital Pusan 602-739 Korea

AIM： To evaluate the effect of incision types for Artisan phakic intraocular lens （PIOL） implantation on ocular higher-order aberrations （HOAs）.METHODS： A retrospective review was conducted of the patients who had undergone Artisan PIOL implantation for the correction of myopia and followed up for at least 6mo. Patients are classified into 2 groups considering the incision type： cornea group with patients undergone clear corneal incision; sclera group with patients undergone sclera tunnel incision. All patients with postoperative astigmatism of under 1 diopter （D） were included to minimize the effect of residual astigmatism on postoperative HOAs. Visual acuity, special equivalents, astigmatism, predictability （±1 D from target refraction）, HOAs （coma, trefoil, spherical aberration）, and corneal endothelial counts were analyzed preoperatively and 6mo ***： At the postoperative 6mo, all patients of both groups achieved uncorrected visual acuity of 16/20 or better, and significantly decreased the spherical equivalents compared with preoperative values. The predictability of refractive correction was 96% in the former, and 94% in the latter. Unlike the sclera group, preoperative astigmatism decreased significantly in cornea group at postoperative 6mo. The HOAs increased significantly at postoperative 6mo compared to the preoperative values in both groups, and the root mean square （RMS） total and trefoil wavefront aberration of cornea group were significantly higher than those of sclera ***： Although corneal incision significantly reduces preexisting astigmatism, the postoperative 6mo of total RMS and trefoil aberration change may deteriorate the visual quality after Artisan PIOL implantation.

关键词： Artisan astigmatism higher-order aberrations incision phakic intraocular lens

Tai Chi for Management of Type 2 Diabetes Mellitus:A Systematic Review

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Chinese Journal of Integrative Medicine 2011年第10期17卷 789-793页

作者： Myeong soo Lee Tae-young Choi Hyun-Ja Lim Edzard Ernst Division of Standard Research Korea Institute of Oriental MedicineDaeieonSouth Korea Complementary Medicine Peninsula Medical SchoolUniversity of ExeterExeterUK Division of Standard Research Korea Institute of Oriental MedicineDaejeonSouth Korea Department of Nursing Chodang UniversityMuanSouth Korea

Objective： Tai chi has been recommended for treating type 2 diabetes mellitus. The purpose of this systematic review was to evaluate evidence from controlled clinical trials testing the effectiveness of tai chi in treating type 2 diabetes mellitus. Methods： Systematic searches were conducted on 14 electronic databases without restrictions on either population characteristics or language of publication. The outcome measures considered for inclusion were changes in fasting blood glucose （FBG）, glycosylated haemoglobin A1c （HbA1c） and quality of life （QOL）. Results： Eight randomised clinical trials （RCTs） and two controlled clinical trials （CCTs） met all inclusion criteria. Three RCTs from 1 trial compared the effects of tai chi with sham exercise and failed to show effectiveness of tai chi on FBG, HbA1c, or QOL. The other 3 RCTs tested the effects of tai chi compared with other types of exercise on FBG. The meta-analysis failed to show an FBG-lowering effect of tai chi [n=118, weighted mean difference （WMD）： -0.14 mmol/L, 95% CI：-0.86 to 0.58,P=0.70]. Four studies （2 RCTs and 2 CCT） compared tai chi with no treatment or self-management programme and failed to report significant differences between the experimental and control groups except for QOL from 1 RCT and 1 CCT. Conclusion： The existing evidence does not suggest that tai chi is an effective therapy for type 2 diabetes. Currently, there are few high-quality trials on which to make definitive judgements.

关键词： type 2 diabetes mellitus tai chi fast blood glucose complementary medicine

MRI of gastric carcinoma:Results of T and N-staging in an in vitro study

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World Journal of Gastroenterology 2009年第32期15卷 3992-3998页

作者： Il young Kim Sang Won Kim Hyeong Cheol Shin Moon soo Lee Dong Jun Jeong Chang Jin Kim young Tong Kim Department of Radiology Soonchunhyang University Cheonan Hospital23-20 BongmyungdongCheonanChoongnam 330-720South Korea Department of Surgery Soonchunhyang University Cheonan Hospital23-20 BongmyungdongCheonanChoongnam 330-720South Korea Department of Pathology Soonchunhyang University Cheonan Hospital23-20 BongmyungdongCheonanChoongnam 330-720South Korea

AIM： To determine the accuracy of 1.5-T magnetic resonance imaging （MRI） in the evaluation of gastric wall invasion and perigastric lymph node metastasis in gastric adenocarcinoma.METHODS： Twenty resected gastric specimens containing 20 tumors were studied with a 1.5-T MR system using a commercial head surface coil. MR scanning was performed with a T1 weighted image （TR/TE = 500/20）, and a T2 weighted image （TR/TE = 2500/90）. MR findings were compared with pathologic findings.RESULTS： A T1-weighted image demonstrated three layers in the normal gastric wall. All of the gastric tumors were well demonstrated by lesions and location. In a MRI findings of gastric wall invasion, there was 1 case of T1, 7 of T2, 11 of T3. Pathologic results of resected specimens included 3 cases of pT1, 4 of pT2, and 12 of pT3. The accuracy of T staging with MRI was 74% （14 of 19）. MRI findings of lymph node metastasis included 6 cases of NO, 13 cases of N1. The accuracy of the N staging with MRI was 47% （9 of 19）.CONCLUSION： MRI has a high diagnostic accuracy in the evaluation of the T staging of gastric cancerin vitro and thus potentially enables preoperative histopathologic staging.

关键词： Gastric cancer Magnetic resonance imaging Neoplasm Staging Stomach Depiction of walllayer

Comparative study of tensile and high-cycle fatigue properties of extruded AZ91 and AZ91-0.3Ca-0.2Y alloys

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Journal of Materials Science & Technology 2021年第34期93卷 41-52页

作者： Ye Jin Kim young Min Kim Seong-Gu Hong Dae Woong Kim Chong soo Lee Sung Hyuk Park School of Materials Science and Engineering Kyungpook National UniversityDaegu 41566Republic of Korea Implementation Research Division Korea Institute of Materials ScienceChangwon 51508Republic of Korea Division of Industrial Metrology Korea Research Institute of Standards and ScienceDaejeon 34113Republic of Korea Energy Infra Material Measure Team Korea Research Institute of Standards and ScienceDaejeon 34113Republic of Korea Graduate Institute of Ferrous Technology Pohang University of Science and Technology.Pohang 37673Republic of Korea

Mg-Al-Zn-Ca-Y alloys with excellent ignition and corrosion resistances—termed SEN alloys(where the letters"S,""E,"and"N"stand for stainless,environmentally friendly,and non-flammable,respectively)—have been developed *** this study,the microstructure,tensile properties,and high-cycle fatigue properties of an extruded Mg-9.0Al-0.8Zn-0.1Mn-0.3Ca-0.2Y(SEN9)alloy are investigated and compared with those of a commercial Mg-9.0Al-0.8Zn-0.1Mn(AZ91)alloy extruded under the same *** the extruded SEN9 alloy and the extruded AZ91 alloy have a fully recrystallized structure comprising equiaxed grains,but the former has a smaller average grain size owing to the promoted dynamic recrystallization during *** extruded AZ91 alloy contains coarse Mg_(17)Al_(12) discontinuous precipitate(DP)bands parallel to the extrusion direction,which are formed during its cool down after *** contrast,the extruded SEN9 alloy contains relatively fine undissolved Al_(2)Ca,Al_(8)Mn_(4)Y,and Al_(2)Y second-phase particles,which are formed during the solidification stage of the casting *** tensile strength of the extruded SEN9 alloy,which has finer grains and more abundant particles,is slightly higher than that of the extruded AZ91 ***,the difference in their strengths is relatively small because the stronger solid-solution hardening and precipitation hardening effects in the extruded AZ91alloy offset the stronger grain-boundary hardening and dispersion hardening effects in the extruded SEN9alloy to some *** tensile elongation of the extruded AZ91 alloy is significantly lower than that of the extruded SEN9 alloy because the large cracks formed in the DP bands in the former cause its premature *** the extruded SEN9 alloy has higher tensile properties than the extruded AZ91alloy,the high-cycle fatigue life and fatigue strength of the former are shorter and lower,respectively,than those of the *** DP bands in the extruded

关键词： Mg-Al-Zn-Ca-Y alloy Extrusion Tensile properties High-cycle fatigue Crack source

Is percutaneous endoscopic gastrostomy tube placement safe in patients with ventriculoperitoneal shunts?

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World Journal of Gastroenterology 2009年第25期15卷 3148-3152页

作者： Jin-soo Kim Yong-Wan Park Hyung-Keun Kim young-Seok Cho Sung-soo Kim Na-Ri Youn Hiun-Suk Chae Division of Gastroenterology Department of Internal MedicineCollege of MedicineThe Catholic University of KoreaUijeongbu St. Mary's Hospital

AIM:To investigate whether percutaneous endoscopic gastrostomy (PEG) tube placement is safe in patients with ventriculoperitoneal (VP) ***: This was a retrospective study of all patients undergoing PEG insertion at our institution between June 1999 and June 2006. Post-PEG complications were compared between two groups according to the presence or absence of VP shunts. VP shunt infection rates, the interval between PEG placement and VP shunt catheter insertion, and long-term follow-up were also ***: Fifty-five patients qualified for the study. Seven patients (12.7%) had pre-existing VP shunts. All patients received prophylactic antibiotics. The complication rate did not differ between VP shunt patients undergoing PEG (PEG/VP group) and non-VP shunt patients undergoing PEG (control group) [1 (14.3%) vs 6 (12.5%), P=1.000]. All patients in the PEG/VP group had undergone VP shunt insertion prior to PEG placement. The mean interval between VP shunt insertion and PEG placement was 308.7 d (range, 65-831 d). The mean follow-up duration in the PEG/VP group was 6.4 mo (range, 1-15 mo). There were no VP shunt infections, although one patient in the PEG/VP group developed a minor peristomal infection during ***: Complications following PEG placement in patients with VP shunts were infrequent in this study.

关键词： Percutaneous endoscopic gastrostomy Ventriculoperitoneal shunt Complication Ventriculo- peritoneal shunt infection Prophylactic antibiotic

^(27)Al MAS-NMR study of inorganic polymer formation at ambient temperature

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Transactions of Nonferrous Metals Society of China 2011年第A1期21卷 182-187页

作者： Sang-Wook AHN Hee-soo LEE Wan-Hee YANG Jung-Woo LEE young-Keun JEONG National Core Research Center for Hybrid Materials Solution Pusan National University School of Material Science and Engineering Pusan National University INTChem Co. Ltd.

Inorganic polymers are a novel class of materials formed by the polymerization of silicon, aluminium and oxygen species to form an amorphous three-dimensional framework structure. The basis of this process is the alkaline solutions to induce a certain amount of Si and AI atoms to dissolve from a feedstock such as aluminosilicate. A study of 27A1 MAS-NMR was carried out in an attempt to understand the reaction mechanism of the inorganic polymerization at ambient temperature. Scanning electron microscopy （SEM） and X-ray diflYactometry （XRD） were also employed to establish the composition and microstructure of the inorganic polymerization. Specimens were prepared with different A1/Si mole ratios from the starting materials. The higher the AI content, the more sufficient the AI atoms that can combine with SiO4, and the longer the reaction time, the more the bonded Si--O--A1--O polymer structure, and then the higher the A1 content, the fewer the octahedral A1 with a uniform Si--O--A1--O structure in four directions, because four AI atoms are combined with SiO4, resulting in a uniform Si--O--AI--O structure in four directions. The results show that they have an amorphous microstructure.

关键词： inorganic polymer amorphous tetrahedral