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Rare Metals 2006年第Z2期25卷 118-123页

作者： LEE Dock-Young KANG Suk-Won CHO Duck-Ho kim ki-bae Division of Materials Korea Institute of Science and Technology P.O. Box 131 Cheongryang Seoul 130-650 Korea Department of Applied Materials Engineering Hanbat National University Daejeon 305-719 Korea

Recently, a semi-solid metal processing has been acknowledged as a cost-effective technique to be able to manufacture high quality product for the transportation industry. In this study a hypo-eutectic Al alloy was fabricated by means of an electromagnetic stirrer in continuous casting process and the microstructural change during solidification due to a fluid flow by electromagnetic stirring was examined. Due to the forced fluid flow during solidification a dendritic phase of primary α phase of Al alloy was turned into a globular phase, which can make the Al alloy get a thixotropic behavior in the semi-solid region. In order to establish the quantitative relationship between microstructure and the process parameters, the morphology shape, a silicon distribution and a size of primary α phase were observed according to casting speed in continuous casting machine. The primary α phase was turned into the degenerate dendrites approaching a spherical configuration with increasing casting speed. The fine-grained and equiaxed microstructure appeared at higher casting speed. A segregation behavior of Si element was declined with increasing casting speed and a very uniform distribution of Si element was observed on the billet at a casting speed of 600 mm·min-1. A thickness of the solidifying shell of the billet was shortened with increasing the casting speed.

关键词： semi-solid slurry electromagnetic stirring casting speed segregation Al alloy

Prominent cycling reversibility and kinetics enabled by CaTiO3 protective layer on Zn metal for aqueous Zn-ion batteries

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Journal of Energy Chemistry 2025年第1期100卷 245-258页

作者： Gaeun Lee Yong Nam Ahn Seongjoon So Chanwoo Park Jong-Seong bae Taehyun Park Il Tae kim Jaehyun Hur School of Chemical Biological and Battery Engineering Gachon University Seongnam Busan Center Korea Basic Science Institute

Aqueous Zn-ion batteries （AZIBs） have received considerable attention owing to their various advantages such as safety,low cost,simple battery assembly conditions,and high ionic ***,they still suffer from serious problems,including uncontrollable dendrite growth,corrosion,hydrogen evolution reaction （HER） from water decomposition,electrode passivation,and unexpected *** creation of a uniform artificial nanocrystal layer on the Zn anode surface is a promising strategy for resolving these ***,we propose the use of a perovskite CaTiO3（CTO） protective layer on Zn（CTO@Zn） as a promising approach for improving the performance of *** CTO artificial layer provides an efficient pathway for Zn ion diffusion towards the Zn metal because of the high dielectric constant （εr=180） and ferroelectric characteristics that enable the alignment of dipole moments and redistribute the Zn2+ions in the CTO *** avoiding the direct contact of the Zn anode with the electrolyte solution,the uneven dendrite growth,corrosion,parasitic side reactions,and HER are mitigated,while CTO retains its mechanical and chemical robustness during ***,CTO@Zn demonstrates an improved lifespan in a symmetric cell configuration compared with bare ***@Zn shows steady overpotential （～68 m V） for 1500 h at 1 mA cm-2/0.5 mA h cm-2,excelling bare ***,when paired with the V2O5-C cathode,the CTO@Zn//V2O5-C full battery delivers 148.4 mA h g-1（based on the mass of the cathode） after 300 *** study provides new insights into Zn metal anodes and the development of high-performance AZIBs.

关键词： Artificial layer Dielectric constant Zn metal anode Zinc aqueous battery

Production of Integrated Automotive Part in High Pressure Diecasting Process Using Salt Core

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Journal of Rare Earths 2004年第Z2期22卷 57-60页

作者： ki-bae kim Hyun-Kwang Seok Jun-Su kim Advanced Materials Research Center Korea Institute of Science and TechnologyP.O.Box 131CheongryangSeoul130-650Korea Advanced Materials Research CenterKorea Institute of Science and TechnologyP.O.Box 131CheongryangSeoul130-650Korea Research & Development CenterTechnology Union Co.Ltd742-1Paeksok-dongChonan-siChungchongnam-do330-220Korea

A new concept of salt core, a melting temperature of which is lower than the solidus temperature of cast alloy,was introduced to produce an integrated casting part having a complicated inner shape or requiring under-cut in high pressure die casting or squeeze casting process. A salt core, named a fusible core in this paper because the salt core can be easily extracted just as holding at a temperature under a solidus temperature of a casting alloy, was developed and applied to produce a fuel control part for automotive GDI engine in high pressure diecasting machine. A different salt material of a lower melting temperature than that of A1 alloy was mixed with a different ceramic particulate to improve a thermo-physical property of fusible core. The thermo-physical property of the fusible core was measured and a weight faction of the ceramic particulate was optimized. The selected core materials were poured in metallic mold by gravity to produce a fusible core for a fuel control part for automotive GDI engine. The fuel control part, which the fusible core was included inside, was successful to fabricate in a conventional diecasting machine with no melting of fusible core during casting.

关键词： salt core high pressure diecasting casting part for automotive fusible core

Prospective comparison of prophylactic antibiotic use between intravenous moxifloxacin and ceftriaxone for high-risk patients with post-ERCP cholangitis

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Hepatobiliary & Pancreatic Diseases International 2017年第5期16卷 512-518页

作者： Nam Hee kim Hong Joo kim ki bae Bang Department of Internal Medicine Sungkyunkwan University Kangbuk Samsung Hospital Department of Internal Medicine Dankook University Hospital

BACKGROUND: The use of prophylactic antibiotics before endoscopic retrograde cholangiopancreatography(ERCP) is recommended by all major international gastroenterological societies, especially in the presence of an obstructed biliary system. This study compared the occurrence rate of post-procedural complications, including cholangitis and septicemia between prophylactic intravenous moxifloxacin and ceftriaxone in patients with bile duct obstruction scheduled for therapeutic ***: From November 2013 to July 2015, 86 consecutive patients with biliary obstruction with one or more factors predicting benefits of antibiotic prophylaxis prior to ERCP were included in the current randomized open-label non-inferiority trial(Clinical *** identifier NCT02098486). Intravenous moxifloxacin(400 mg/day) or ceftriaxone(2 g/day)were given 90 minutes before ERCP, and were administered for more than 3 days if the patient developed symptoms and signs of cholangitis or septicemia. Recalcitrant cholangitis was defined as persistence of cholangitis for more than 5 days after ERCP or recurrence of cholangitis within 30 days after ***: Recalcitrant cholangitis occurred in 1(2.3%) and 2(4.8%) patients receiving intravenous moxifloxacin and ceftriaxone group, respectively(P=0.612). Septicemia was noted in1(2.3%) and 1(2.4%) patient in intravenous moxifloxacin and ceftriaxone group, respectively(P=1.0). The mean hospital stay was also not significantly different between the moxifloxacin and ceftriaxone groups(8.8±7.2 vs 9.1±9.4 days, P=0.867). Antibiotic resistance of the isolated pathogens by in vitro activity assay was noted in 1(2.3%) and 2(4.8%) patients in the moxifloxacin and ceftriaxone group, respectively(P=0.612). CONCLUSION: Intravenous moxifloxacin is not inferior to intravenous ceftriaxone for the prophylactic treatment of post-ERCP cholangitis and cholangitis-associated morbidity.

关键词： endoscopic retrograde cholangiopancreatography cholangitis moxifloxacin ceftriaxone recalcitrant cholangitis

Management of antiviral drug resistance in chronic hepatitis B

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World Journal of Gastroenterology 2014年第33期20卷 11641-11649页

作者： ki bae Bang Hong Joo kim Department of Internal Medicine Sungkyunkwan University Kangbuk Samsung Hospital Seoul 110-746 South Korea

Rescue antiviral treatment for patients with resistance to preexisting nucleos(t)ide analogues remains a clinical challenge. The correct choice of a first-line treatment of high potency and with a high genetic barrier to achieve sustained long-term suppression of viral replication provides the best chance of preventing treatment failure and the emergence of drug resistance. The management of treatment failure and drug resistance requires a precise and accurate clinical and virologic monitoring. Combination treatment with antiviral drugs that belong to different groups is associated with a lower chance of developing resistance to rescue drugs. To guarantee better control of viral replication in patients with drug resistance, the addition of another drug without a cross resistance profile should be given as early as possible, preferably at the time when genotypic resistance emerges. Long-term surveillance for treatment efficacy and possible emergence of drug resistance should be continued to prevent the emergence of multidrug-resistant strains.

关键词： Chronic hepatitis B Antiviral resistance Rescue treatment Multidrug resistance Cross resistance

Development of tenofovir disoproxil fumarate resistance after complete viral suppression in a patient with treatment-na?ve chronic hepatitis B: A case report and review of the literature

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World Journal of Gastroenterology 2018年第17期24卷 1919-1924页

作者： Woo Hee Cho Hyun Jae Lee ki bae Bang Seok bae kim Il Han Song Department of Internal Medicine Dankook University College of MedicineCheonan 31116South Korea

Tenofovir disoproxil fumarate(TDF) is a potent nucleo-tide analogue that is recommended as first-line therapy for patients with chronic hepatitis B. The results of a longitudinal study of TDF treatment demonstrated no development of resistance. We observed one treatment-na?ve chronic hepatitis B(CHB) patient who developed TDF resistance after complete viral suppression during long-term TDF treatment. A 37-year-old HBe Ag-positive man received TDF 300 mg/d for 43 mo. The hepatitis B virus(HBV) DNA titer was 8 log_(10) copies/m L at baseline and became undetectable at 16 mo after treatment. However, the HBV DNA titer rebounded to 7.5 log_(10) copies/m L at 43 mo after treatment. We performed full sequencing to find mutation sites associated with virologic breakthrough. The results showed 9 mutation sites, most of which had not been well-known as mutation sites. We changed the therapy from tenofovir to entecavir with a regimen of 0.5 mg once daily. After 4 mo, the HBV DNA titer decreased to 267 copies/m L, and the liver enzyme levels were normalized.

关键词： Chronic hepatitis B Tenofovir Resistance Mutation

N-doped carbon-embedded TiN nanowires as a multifunctional separator for Li–S batteries with enhanced rate capability and cycle stability

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Journal of Energy Chemistry 2021年第6期30卷 10-18,I0001页

作者： Yoongon kim Yuseong Noh Jaejin bae Hyunwoo Ahn Minho kim Won bae kim Department of Chemical Engineering Pohang University of Science and Technology(POSTECH)77 Cheongam-roNam-guPohang 37673South Korea

Lithium-sulfur(Li-S)batteries have attracted considerable attention as next-generation energy storage devices owing to their high theoretical specific capacity and ***,the commercialization of Li-S batteries is hindered by critical issues,including the migration of the dissolved lithium polysulfides(LiPSs)from the sulfur electrode to the lithium metal anode,resulting in poor cycling ***,we report a multifunctional interlayer configured with an N-doped carbon framework and titanium nitride nanowires on a polypropylene separator(NC/TiN NWs@PP)to suppress the polysulfide shuttling ***/TiN NWs@PP can be obtained by electrospinning and the subsequent scalable solution-based vacuum *** one-dimensional structure of the TiN NWs can shorten the Li-ion diffusion distance with large electrode/electrolyte ***,the N-doped carbon framework in the NWs enables facile electron transportation and allows the suppression of the shuttle effect to improve the electrochemical reaction *** Li-S battery with a NC/TiN NWs@PP separator exhibited enhanced cycling stability and rate capability,indicating that this could be a new research direction for Li-S batteries.

关键词： Li-S battery Shuttle effect Interlayer Separator TiN N-doped carbon 1D Nanowire

Carbonaceous aerosol in ambient air: Parallel measurements between water cyclone and carbon analyzer

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Particuology 2019年第3期17卷 153-158页

作者： Min-Suk bae James J. Schwab Da-Jeong Park Zang-Ho Shon ki-Hyun kim Department of Environmental Engineering Mokpo National University Muan South Korea Atmospheric Sciences Research Center University at Albany State University of New York 251 Fuller Road Albany NY 12203 USA Environmental Analysis Center Gwangju Institute of Science and Technology Gwangju South Korea Department of Environmental Engineering Dong-Eui University Busan South Korea Department of Civil and Environmental Engineering Hanyang University Seoul South Korea

A water cyclone,developed to collect and preserve biological aerosols in a small liquid flow,was interfaced with a total organic carbon analyzer to measure the aerosol organic and inorganic carbon *** total carbon was compared against parallel measurements of elemental carbon (EC) and organic carbon (OC) using a Sunset Real Time ECOC Analyzer between 12-29 January 2009.A National Institute for Occupational Safety and Health (NIOSH) like protocol for the measurements included four temperature steps ending at 840 ℃ for OC under a helium atmosphere followed by two temperature steps ramped to 850 ℃ for EC in a helium-oxygen atmosphere,Carbon data comparison between the water cyclone-TOC and the TOC measured by the analyzer indicated good agreement (r2 =0.82,linear regression slope =0.98,p < 0.001).Analyses of the relationship between total water organic carbon and OC,investigated using data sets from case studies spanning two different events,suggested it was possible to distinguish between the primary and secondary sources.

关键词： Water soluble organic carbon Total organic carbon Carbonaceous material

Endoluminal closure of an unrecognized penetrating stab wound of the duodenum with endoscopic band ligation: A case report

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World Journal of Clinical Cases 2019年第20期7卷 3271-3275页

作者： Dae Hoon kim Hanlim Choi ki bae kim Hyo Yung Yun Joung-Ho Han Department of Surgery Chungbuk National University HospitalChungbuk National University College of MedicineCheongju-si 28644South Korea Department of Internal Medicine Chungbuk National University HospitalChungbuk National University College of MedicineCheongju-si 28644South Korea

BACKGROUND A penetrating injury of a hollow viscus is an obvious indication for an exploratory laparotomy,but is not typically an indication for endoscopic *** SUMMARY A 27-year-old man visited the emergency department with a self-inflicted abdominal stab *** to the colon and ileum were detected,but an injury to the second portion of the duodenum was *** the day following admission to our institution,the patient became hemodynamically unstable with massive hematochezia,although there was no evidence of bleeding in the Levin tube or Jackson-Pratt *** thus performed an upper gastrointestinal endoscopy and discovered a missed duodenal injury that was actively *** endoscopic band ligation was performed for hemostasis and closure of the *** patient was subsequently discharged without any *** A penetrating injury of the duodenum can be overlooked,so careful abdominal exploration is very *** a missed duodenal injury is suspected,a cautious endoscopic approach may be helpful.

关键词： Penetrating abdominal injury Endoluminal treatment Unrecognized duodenal injury Case report

Bile-derived circulating extracellular mi R-30d-5p and mi R-92a-3p as potential biomarkers for cholangiocarcinoma

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Hepatobiliary & Pancreatic Diseases International 2020年第1期19卷 41-50页

作者： Hye Sook Han Mi Jin kim Joung-Ho Han Jieun Yun Hee Kyung kim Yaewon Yang ki bae kim Seon Mee Park Department of Internal Medicine Chungbuk National University HospitalCheongju 28644Korea Departments of Internal Medicine Chungbuk National University College of MedicineCheongju 28644Korea Department of Pharmaceutical Engineering College of Science EngineeringCheongju UniversityCheongju 28644Korea

Background: Cholangiocarcinoma (CCA) is from cholangiocytes, and therefore bile is a potentially rich source of biomarkers for CCA. The aim of the study was to identify and validate microRNAs (miRNAs) in bile samples that are differentially expressed between benign biliary disease (BBD) and CCA. Methods: Bile samples from 106 patients with obstructive biliary disease were allocated consecutively to a discovery set (10 patients with BBD and 11 with CCA) and then a validation set (48 patients with BBD and 37 with CCA). An miRNA microarray platform was used to screen 1209 miRNAs in the discovery set. Quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR) was used to validate the pro ling results in the discovery and validation sets. In addition, the levels of carbohydrate antigen 19-9 (CA19-9) and carcinoembryonic antigen (CEA) were determined from patient serum samples. Results: Microarray pro ling showed that miR-30d-5p and miR-92a-3p were signi cantly upregulated in bile from the CCA group compared with those from the BBD group. qRT-PCR results indicated that the expression levels of miR-30d-5p and of miR-92a-3p were signi cantly upregulated in the CCA group compared to the BBD group, validating the miRNA microarray results. Pathway analysis suggested that putative target genes of miR-30d-5p and of miR-92a-3p were involved in CCA-associated signalling path- ways, such as Hippo, Wnt, p53, MAPK, and EGFR. Receiver operating curve analysis revealed that the areas under the curve for bile miR-30d-5p, miR-92a-3p, serum CA19-9, and CEA were 0.730, 0.652, 0.675, and 0.603, respectively, and bile miR-30d-5p showed the best diagnostic performance with a sensitivity of 81.1% and a speci city of 60.5%. Conclusions: The levels of extracellular miR-30d-5p and miR-92a-3p in bile were signi cantly higher in patients with CCA than those in patients with BBD. Bile-derived circulating extracellular miR-30d-5p and miR-92a-3p are potential biomarkers for discr

关键词： Bile Biomarkers Cholangiocarcinoma MicroRNA