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Plasma Science and Technology 2020年第7期22卷 110-115页

作者： Seul-Ki HAN Se-Hwan PARK seong-kyu ahn Korea Atomic Energy Research Institute Yuseong-guDaejeon 34057Republic of Korea

In pyroprocessing,uranium(U) is recovered from molten LiCl-KCl salt,and,for safeguard purposes,it is important to analyze the U and Plutonium(Pu) concentrations in a timely *** the present work,salt samples containing U were *** laser used in the present work was an Nd:YAG laser with a wavelength of 532 nm,a laser energy on the sample of11.5 mJ,and a pulse repetition rate of 10 *** plasma emission light was measured with an Echelle spectrometer.A total of 100 points on the sample surface were measured as the laser incident position was *** U and potassium(K) peaks in the spectrum were *** and multivariate analyzes were conducted to determine the accuracy and limit of detection(LOD) of the laser-induced breakdown spectroscopy.

关键词： LIBS uranium(U) safeguards LOD

Quantitative analysis of uranium in electrorecovery salt of pyroprocessing using laser-induced breakdown spectroscopy

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Plasma Science and Technology 2021年第5期23卷 96-103页

作者： Seul-Ki HAN Se-Hwan PARK seong-kyu ahn Korea Atomic Energy Research Institute Yuseong-guDaejeon 34057Republic of Korea Korea Institute of Industrial Technology Yeonsu-guIncheon21999Republic of Korea

The amounts of nuclear materials in the Li Cl-KCl salt in pyroprocessing have to be analyzed to prevent the diversion of the nuclear *** alternative method to the chemical analysis has been pursued,and laser-induced breakdown spectroscopy(LIBS)is one *** the present work,an in situ and quantitative analysis method of electro-recovery(ER)salt was proposed and demonstrated by using LIBS combined with dipstick *** types of simulated salt samples were prepared:ER salt sample and salt obtained from the dipstick sampling,and pulsed neodymium-doped yttrium aluminum garnet(Nd:YAG)laser with a wavelength of 532 nm was focused on the salt to generate *** plasma emission was measured by using an Echelle spectrometer with a resolution of 0.01 nm in conjunction with an Intensified Charge-Coupled Detector *** U and other rare earth peaks in the spectra were *** best Limit of Detection and Root Mean Square Error of Calibration of U were 38 ppm and 0.0203 wt%,*** work shows that the U in the pyroprocessing ER salt can be monitored with LIBS.

关键词： LIBS uranium LOD RMSEC

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： Perovskite

Fibrinogen’s potential role in connecting cerebrovascular abnormalities with glymphatic dysfunction in Alzheimer’s disease

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Neural Regeneration Research 2025年第1期20卷 203-204页

作者： Vishal Singh Arnab Choudhury Hyung Jin ahn Department of Pharmacology Physiology and NeurosciencesRutgers-New Jersey Medical SchoolNewarkNJUSA Brain Health Institute Rutgers UniversityPiscatawayNJUSA

Alzheimer’s disease(AD)stands out as the primary manifestation of age-related dementia,portraying a chronic neurodegenerative disorder distinguished by the accumulation of fibrillar amyloid-β(Aβ)plaques and neurofibrillary tangles of hyperphosphorylated ***,from a clinical standpoint,AD presents itself as a complex condition with a spectrum of dysfunctions rather than a singular pathological *** often-overlooked aspect of the disease is the presence of extensive cerebrovascular abnormalities,given that the majority of AD patients experience altered cerebral blood flow,damaged vasculature,increased microinfarcts and *** models of AD further support this observation,showing cerebrovascular dysfunction such as impaired cerebral blood flow and altered cerebrovascular reactivity(Tataryn et al.,2021;Gareau et al.,2023).

关键词： cerebrovascular dysfunction Alzheimer

Maximizing biomass utilization: An integrated strategy for coproducing multiple chemicals

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Journal of Energy Chemistry 2025年第1期100卷 180-191页

作者： Byeongchan ahn Sua Jo Jonggeol Na J.Jay Liu Young-Ju Kim Wangyun Won Department of Chemical and Biological Engineering Korea University Department of Chemical Engineering (Integrated process) Kyung Hee University Department of Chemical Engineering and Materials Science Ewha Womans University Department of Chemical Engineering Pukyong National University Resources Engineering Plant Research Department Korea Institute of Geoscience and Mineral Resources

Lignocellulosic biomass is one of the viable solutions to alleviate the global warming. However, the limited utilization of biomass majorly focused on cellulose and hemicellulose restricts the economic and environmental feasibilities. To cope with this issue, we proposed an integrated process of co-producing 1,6-hexanediol（1,6-HDO） with tetrahydrofuran and adipic acid from biomass, referred to as Strategy A. To compare the impacts of lignin upgrading and feedstock, Strategy B, which co-produces tetrahydrofuran alone, and Strategy C, which is the traditional route to produce 1,6-HDO from fossil fuels, were used. Heat networks are also designed to reduce operating costs and indirect carbon emissions due to energy consumption, saving 87% and 83% of the heat and cooling requirements, respectively, in Strategy A. The market competitiveness of Strategy A was evaluated by determining the minimum selling price through techno-economic analysis, and sustainability was thoroughly investigated by quantifying the environmental impacts through both midpoint and endpoint life-cycle assessments（LCAs）.Strategy A was found to be the most favorable both economically（USRDSCHARDOLLAR3,402/ton） and environmentally（-26.9 kg CO2eq.）. This indicates that lignin valorization is not only economically but also environmentally preferred. Finally, changes in economic and environmental feasibilities depending on economic, process, and environmental parameters were investigated using sensitivity and uncertainty analyses. The results of these analyses provide valuable insight into bio-based chemical production.

关键词： Carbon capture and utilization

Review of simulation model for education of point-of-care ultrasound using easy-to-make tools

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World Journal of Clinical Cases 2020年第19期8卷 4286-4302页

作者： kyu Chul Shi Young Rock Ha seong-Joon Lee Jung Hwan ahn Department of Emergency Medicine Ajou University School of MedicineSuwon 16499Gyeonggi-doSouth Korea Department of Emergency Medicine Bundang Jesaeng HospitalSeongnam-si 13590South Korea Department of Neurology Ajou University School of MedicineSuwon 16499Gyeonggi-doSouth Korea

Point-of-care ultrasound(POCUS)is a powerful diagnostic tool and provides treatment guidelines in acute critical ***,the limitation of using POCUS is operator *** and validated training for acquiring and using skills in practice must be conducted before using POCUS in clinical settings in order to keep patients *** education models have been introduced as a way to solve and overcome these ***,the commercial simulator with sufficiently secured fidelity is expensive and not always *** review focused on the inexpensive and easily made simulators for education on POCUS in critical specific situations related to the airway,breathing,circulation,and *** introduced the simulators that used non-infectious materials,with easily transportable features,and that had a sonographic appearance reproducibility similar to human *** also introduced the recipe of each simulator in two parts:Materials surrounding disease simulators(surrounding materials)and specific disease simulators themselves(target simulators).This review article covered the following:endotracheal or oesophageal intubation,lung(A-lines,B-lines,lung sliding,and pleural effusions such as hemothorax),central vein access,pericardial fluid(cardiac tamponade),the structure related to the eyes,soft tissue abscess,nerve(regional nerve block),and skull fracture simulators.

关键词： Critical care Education Emergency medicine Simulation training Point-of care Ultrasonography

Invariant submanifolds for systems of vector fields of constant rank

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Science China Mathematics 2016年第7期59卷 1417-1426页

作者： ahn Heung Ju HAN Chong kyu School of Undergraduate Study Daegu Gyeongbuk Institute of Sceince and Technology Department of Mathematics College of Natural SciencesSeoul National University

Given a system of vector fields on a smooth manifold that spans a plane field of constant rank, we present a systematic method and an algorithm to find submanifolds that are invariant under the flows of the vector fields. We present examples of partition into invariant submanifolds, which further gives partition into orbits. We use the method of generalized Frobenius theorem by means of exterior differential systems.

关键词： control system vector fields reachability orbits invariant submanifolds

Effect of carbon on microstructure of CrAlC_xN_(1-x) coatings by hybrid coating system

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Transactions of Nonferrous Metals Society of China 2011年第A1期21卷 78-82页

作者： Sung-kyu ahn Se-Hun KWON Kwang-Ho KIM National Core Research Center for Hybrid Materials Solution Pusan National University School of Materials Science and Engineering Pusan National University

A systematic investigation of the microstructure of CrA1CxN1-x coatings as a function of carbon contents was conducted. Quaternary CrA1CxN1-x coatings were deposited on Si wafers by a hybrid coating system combining an arc-ion plating technique and a DC reactive magnetron sputtering technique using Cr and AI targets in the Ar/N2/CH4 gaseous mixture. The effect of carbon content on microstructure of CrA1C^N~ x coatings was investigated with instrumental analyses of X-ray diffraction, X-ray photoelectron, and high-resolution transmission electron microscopy. The results show that the carbon content of CrA1CxN1-x coatings linearly increases with increasing CH4/（CH4/N2） gas flow rate ratio. The surface roughness of the CrA1CxN1-x coating layer decreases with the increase of carbon content.

关键词： CrA1C,N1-x, coating nanocomposite microstructure hybrid coating system

Effect of post heat-treatment on the microstructure and high-temperature oxidation behavior of precipitation hardened IN738LC superalloy fabricated by selective laser melting

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Journal of Materials Science & Technology 2021年第17期76卷 95-103页

作者： kyu-Sik Kim Sangsun Yang Myeong-Se Kim Kee-ahn Lee Department of Materials Science and Engineering Inha UniversityIncheon 22212Republic of Korea Korea Institute of Materials Science Changwon51508Republic of Korea Auratech Co. Ltd.Seongnam13449Republic of Korea

The present study investigated the effect of as-built and post heat-treated microstructures of IN738LC alloy fabricated via selective laser melting process on high temperature oxidation *** as-built microstructure showed fine cell and columnar structure due to high cooling *** element segregation was observed in inter-cell/inter-columnar *** post heat-treatment,the initially-observed cell structure disappeared,instead bimodal Ni_3(Al,Ti)particles *** temperature(1273 K and 1373 K)oxidation test results showed parabolic oxidation curves regardless of temperature and initial *** as-built IN738LC fabricated via the selective laser melting process displayed oxidation resistance similar to or slightly better than that of IN738LC fabricated via wrought or cast ***-treated SLM IN738LC,although had similar oxidation weight-gain values to those of the SLM asbuilt material at 1273K,showed relatively better oxidation resistance at 1373 *** Ni_3(Al,Ti)precipitate formed in the post heat treatment changed the local chemical composition,thereby led to changes in alumina former/chromia former location and fraction on the alloy *** was concluded that in heat-treated IN738LC increased alumina former fraction was found,and this resulted in excellent oxidation resistance and relatively low weight-gain.

关键词： IN738LC Selective laser melting High temperature oxidation Post heat-treatment Oxidation mechanism

Endoscopic resection of co-existing severe dysplasia and a small esophageal leiomyoma

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World Journal of Gastroenterology 2013年第1期19卷 137-140页

作者： Sun Young ahn seong Woo Jeon Division of Gastroenterology and Hepatology Department of Internal MedicineKyungpook National University HospitalDaegu 700-721South Korea

Leiomyoma is the most common benign mesenchymal tumor of the esophagus.A small leiomyoma covered with endoscopically normal mucosa has a characteristic endoscopic ultrasonographic appearance,slow growth rate,and negligible risk of malignant transformation;therefore the histology does not need to be *** tumors such as an epithelial tumor and small subepithelial tumor in the upper gastrointestinal tract are *** describe a case with a coexisting small leiomyoma and severe dysplasia in the esophagus which were completely resected by endoscopic mucosal resection.

关键词： Synchronous tumor Leiomyoma Dysplasia