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Carbon Energy 2023年第10期5卷 25-39页

作者： Madagonda MVadiyar Ji‐Young Kim jee‐hwan bae Kyung‐Wan Nam Department of Energy and Materials Engineering Dongguk UniversitySeoulSouth Korea Advanced Analysis&Data Center Korea Institute of Science and Technology(KIST)SeoulSouth Korea Advanced Energy and Electronic Materials Research Center Dongguk UniversitySeoulSouth Korea

Carbon super-heterostructures with high nitrogen contents from the covalent hybrid precursors of covalent triazine frameworks(CTFs)and zeolitic imidazolic frameworks(ZIFs)are scarcely explored because of CTF's ordered structure and toxic superacid that dissolves or destabilizes the metal *** solve this problem,herein,we report a straightforward two-step pathway for the covalent hybridization of disordered CTF(d–CTF)–ZIF composites via preincorporation of an imidazole(IM)linker into ordered CTFs,followed by the imidazole-site-specific covalent growth of *** carbonization of these synthesized d–CTF−IM−ZIF hybrids results in unique hollow carbon super-heterostructures with ultrahigh nitrogen content(>18.6%),high specific surface area(1663m^(2)g^(−1)),and beneficial trace metal(Co/Zn NPs)contents for promoting the redox *** proof of concept,the obtained carbon super-heterostructure(Co–Zn–NC_(SNH)–800)is used as a positive electrode in an asymmetric supercapacitor,demonstrating a remarkable energy density of 61Wh kg^(−1)and extraordinary cyclic stability of 97%retention after 30,000 cycles at the cell *** presynthetic modifications of CTF and their covalent hybridization with ZIF crystals pave the way toward new design strategies for synthesizing functional porous carbon materials for promising energy applications.

关键词： asymmetric supercapacitor defective covalent triazine frameworks hollow carbon superheterostructures linker defect

Effects of Cr doping on structural and electrochemical properties of Li_(4)Ti_(5)O_(12) nanostructure for sodium-ion battery anode

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Journal of Energy Chemistry 2021年第8期30卷 465-472,I0010页

作者： Sang Hyuk Gong Ji Hyeon Lee Dong Won Chun jee-hwan bae Sung-Chul Kim Seungho Yu Sahn Nahm Hyung-Seok Kim Center for Energy Storage Research Korea Institute of Science and Technology5Hwarang-ro 14-gilSeongbuk-gu02792 SeoulRepublic of Korea Department of Materials Science and Engineering Korea University145Anam-roSeongbuk-gu02841 SeoulRepublic of Korea Department of Chemical and Biological Engineering Korea University145Anam-roSeongbuk-gu02841 SeoulRepublic of Korea Advanced Analysis Center Korea Institute of Science and Technology5Hwarang-ro 14-gilSeongbuk-gu02792 SeoulRepublic of Korea

Sodium-ion batteries are considered as promising alternatives to lithium-ion batteries,owing to their low cost and abundant raw *** the several candidate materials for the anode,spinel-type Li_(4)Ti_(5)O_(12)has potential owing to its superior safety originating from an appropriate operating voltage and the reversible Na^(+)intercalation ***,a low diffusion coefficient for Na^(+)and the insulating nature of LTO remains challenging for practical sodium-ion battery ***,we present a strategy for integrating physical and chemical approaches to achieve superior electrochemical properties in *** demonstrate that carefully controlling the amount of Cr doping is crucial to enhance the electrochemical properties of nanostructured *** Cr doped LTO shows a superior reversible capacity of 110 m Ah g^(-1) after 400 cycles at 1 C,with a three-fold higher capacity(75 m Ah g^(-1))at 10 C compared with undoped LTO *** suggests that appropriately Cr doped nanostructured LTO is a promising anode material for sodium-ion batteries.

关键词： Sodium-ion batteries Spinel type Li_(4)Ti_(5)O_(12) Anode materials Nanostructuring Cr-doping

Effect of tellurium on the microstructure and mechanical properties of Fe-14Cr oxide-dispersion-strengthened steels produced by additive manufacturing

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Journal of Materials Science & Technology 2021年第36期95卷 114-126页

作者： Barton Mensah Arkhurst jee hwan bae Min Young Na Hye Jung Chang Hyun Gil Kim Il Hyun Kim Ho Jin Ryu Jeoung Han Kim School of Materials Science and Engineering University of New South Wales SydneyNSW 2052Australia Advanced Analysis Center Korea Institute of Science and Technology SeoulSeongbuk-guRepublic of Korea LWR Fuel Technology Division Korea Atomic Energy Research InstituteDaejeonYuseong-guRepublic of Korea Department of Nuclear and Quantum Engineering KAISTDaejeonYuseong-guRepublic of Korea Department of Materials Science&Engineering Hanbat National UniversityRepublic of Korea

Conventionally,Te has primarily been used to improve the machinability of steel and its *** this work,Te was used to refine the grains of an oxide-dispersion-strengthened(ODS)steel produced by additive manufacturing(AM)with fixed processing *** of Te to the raw powder produced an ODS steel with a fine-grained microstructure,in contrast to the ODS steel manufactured without ***,the addition of Te resulted in superior yield strength and ultimate tensile strength,which was attributed to the combined effects of grain refinement and the finer nanoparticles(NPs)composed of Terich composite NPs and Cr-rich *** the first time,the AM technique was used to obtain grain and nanoparticle sizes of~3.4μm and 6 nm,respectively,from the Te-added ODS steel.

关键词： Additive manufacturing Directed energy deposition Oxide-dispersion-strengthened steel Nanoparticle Tellurium

Thermodynamic model for deoxidation of liquid steel considering strong metal-oxygen interaction in the quasichemical model framework

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International Journal of Minerals,Metallurgy and Materials 2024年第5期31卷 988-1002页

作者： Yong-Min Cho Youn-bae Kang Graduate Institute of Ferrous and Eco Materials Technology Pohang University of Science and TechnologyPohangKyungbuk37673Rep.of Korea N.EX.T Hub POSCO HoldingsPohangKyungbuk37673Rep.of Korea Department of Materials Science and Engineering Pohang University of Science and TechnologyPohangKyungbuk37673Rep.of Korea

Herein,a thermodynamic model aimed at describing deoxidation equilibria in liquid steel was *** model provides explicit forms of the activity coefficient of solutes in liquid steel,eliminating the need for the minimization of internal Gibbs energy preliminarily when solving deoxidation *** elimination of internal Gibbs energy minimization is particularly advantageous during the coupling of deoxidation equilibrium calculations with computationally intensive approaches,such as computational fluid *** model enables efficient calculations through direct embedment of the explicit forms of activity coefficient in the computing *** proposed thermodynamic model was developed using a quasichemical approach with two key approximations:random mixing of metallic elements(Fe and oxidizing metal) and strong nonrandom pairing of metal and oxygen as nearest *** these approximations,the quasichemical approach yielded the activity coefficients of solutes as explicit functions of composition and temperature without requiring the minimization of internal Gibbs energy or the coupling of separate *** model was successfully applied in the calculation of deoxidation equilibria of various elements(Al,B,C,Ca,Ce,Cr,La,Mg,Mn,Nb,Si,Ti,V,and Zr).The limitations of the model arising from these assumptions were also discussed.

关键词： deoxidation equilibria thermodynamics quasichemical approach computational fluid dynamics

Classification and technical target of water electrolysis for hydrogen production

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Journal of Energy Chemistry 2024年第8期95卷 554-576,I0012页

作者： Kahyun Ham Sooan bae Jaeyoung Lee Ertl Center for Electrochemistry and Catalysis Gwangju Institute of Science and Technology(GIST)123 Cheomdangwagi-RoBuk-guGwangju 61005South Korea Department of Heterogeneous Reactions Max Planck Institute for Chemical Energy ConversionStiftstr.34-36Mülheim an der RuhrGermany School of Earth Sciences and Environmental Engineering GIST123 CheomdangwagiroBuk-guGwangju 61005South Korea International Future Research Center of Chemical Energy Storage and Conversion Processes GIST123 CheomdangwagiroBuk-guGwangju 61005South Korea eSuS Co. Ltd.#408S6 BuildingSchool of Environment and Energy EngineeringGIST123 CheomdangwagiroBuk-guGwangju 61005South Korea

Continuous efforts are underway to reduce carbon emissions worldwide in response to global climate *** electrolysis technology,in conjunction with renewable energy,is considered the most feasible hydrogen production technology based on the viable possibility of large-scale hydrogen production and the zero-carbon-emission nature of the ***,for hydrogen produced via water electrolysis systems to be utilized in various fields in practice,the unit cost of hydrogen production must be reduced to$1/kg H_(2).To achieve this unit cost,technical targets for water electrolysis have been suggested regarding components in the *** this paper,the types of water electrolysis systems and the limitations of water electrolysis system components are *** suggest guideline with recent trend for achieving this technical target and insights for the potential utilization of water electrolysis technology.

关键词： Water electrolysis Hydrogen production Technical target Electrochemistry

Benefit in physical function and quality of life to nonsurgical treatment of varicose veins: Pilot study

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World Journal of Clinical Cases 2024年第3期12卷 517-524页

作者： Gwon-Min Kim BoKun Kim Minwoo Jang Jong-hwan Park Miju bae Chung Won Lee Jong Won Kim Up Huh Medical Research Institute Pusan National University School of MedicineYangsan 50612South Korea Future Convergence Research Institute Changwon National UniversityChangwon 51140South Korea Department of Convergence Medical Science School of MedicinePusan National UniversityYangsan 50612South Korea Health Convergence Medicine Laboratory Biomedical Research InstitutePusan National University HospitalBusan 49241South Korea Department of Thoracic and Cardiovascular Surgery Pusan National University School of MedicineBiomedical Research InstitutePusan National University HospitalBusan 49241South Korea

BACKGROUND Studies on varicose veins have focused its effects on physical function;however,whether nonsurgical treatments alter muscle oxygenation or physical function remains ***,the differences in such functions between individuals with varicose veins and healthy individuals remain *** To investigate changes in physical function and the quality of life(QOL)following nonsurgical treatment of patients with varicose veins and determine the changes in their muscle oxygenation during *** We enrolled 37 participants(those with varicose veins,n=17;healthy individuals,n=20).We performed the following measurements pre-and post-nonsurgical treatment in the varicose vein patients and healthy individuals:Calf muscle oxygenation during the two-minute step test,open eyes one-leg stance,30 s sit-to-stand test,visual analog scale(VAS)for pain,Pittsburgh sleep quality index,physical activity assessment,and QOL *** Varicose veins patients and healthy individuals differ in most variables(physical function,sleep quality,and QOL).Varicose veins patients showed significant differences between pre-and post-nonsurgical treatment—results in the 30 sit-to-stand test[14.41(2.45)to 16.35(4.11),P=0.018],two-minute step test[162.29(25.98)to 170.65(23.80),P=0.037],VAS for pain[5.35(1.90)to 3.88(1.73),P=0.004],and QOL[39.34(19.98)to 26.69(17.02),P=0.005];however,no significant difference was observed for muscle *** Nonsurgical treatment improved lower extremity function and QOL in varicose veins patients,bringing their condition close to that of healthy *** studies should include patients with severe varicose veins requiring surgery to confirm our findings.

关键词： Varicose vein Nonsurgical treatment Physical function Quality of life Near infrared spectroscopy

Novel Perovskite Oxide Hybrid Nanofibers Embedded with Nanocatalysts for Highly Efficient and Durable Electrodes in Direct CO_(2) Electrolysis

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Nano-Micro Letters 2024年第5期16卷 214-230页

作者： Akromjon Akhmadjonov Kyung Taek bae Kang Taek Lee Department of Mechanical Engineering KAISTDaejeon 34141Republic of Korea KAIST Graduate School of Green Growth and Sustainability Daejeon 34141Republic of Korea

The unique characteristics of nanofibers in rational electrode design enable effec-tive utilization and maximizing material properties for achieving highly efficient and sustainable CO_(2) reduction reactions( CO_(2)RRs)in solid oxide elec-trolysis cells(SOECs).However,practical appli-cation of nanofiber-based electrodes faces chal-lenges in establishing sufficient interfacial contact and adhesion with the dense *** tackle this challenge,a novel hybrid nanofiber electrode,La_(0.6)Sr_(0.4)Co_(0.15)Fe_(0.8)Pd_(0.05)O_(3-δ)(H-LSCFP),is developed by strategically incorporating low aspect ratio crushed LSCFP nanofibers into the excess porous interspace of a high aspect ratio LSCFP nanofiber framework synthesized via electrospinning *** consecutive treatment in 100% H_(2) and CO_(2) at 700°C,LSCFP nanofibers form a perovskite phase with in situ exsolved Co metal nanocatalysts and a high concentration of oxygen species on the surface,enhancing CO_(2) *** SOEC with the H-LSCFP electrode yielded an outstanding current density of 2.2 A cm^(-2) in CO_(2) at 800°C and 1.5 V,setting a new benchmark among reported nanofiber-based *** twinning of the H-LSCFP reveals improved contact adhesion and increased reaction sites for CO_(2)*** present work demonstrates a highly catalytically active and robust nanofiber-based fuel electrode with a hybrid structure,paving the way for further advancements and nanofiber applications in CO_(2)-SOECs.

关键词： Nanofibers Fuel electrodes Digital twinning CO_(2)reduction reaction Solid oxide electrolysis cells

Negative Stiffness Mechanism on An Asymmetric Wave Energy Converter by Using A Weakly Nonlinear Potential Model

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China Ocean Engineering 2024年第4期38卷 689-700页

作者： Sunny Kumar POGULURI Dongeun KIM Yoon Hyeok bae Department of Ocean Engineering IIT MadrasChennaiIndia Multidisciplinary Graduate School Program for Wind Energy Jeju National UniversityJejuRepublic of Korea Mechanical and System Design Engineering Hongik UniversitySeoulRepublic of Korea

Salter's duck,an asymmetrical wave energy converter(WEC)device,showed high efficiency in extracting energy from 2D regular waves in the past;yet,challenges remain for fluctuating wave *** can potentially be addressed by adopting a negative stiffness mechanism(NSM)in WEC devices to enhance system efficiency,even in highly nonlinear and steep 3D waves.A weakly nonlinear model was developed which incorporated a nonlinear restoring moment and NSM into the linear formulations and was applied to an asymmetric WEC using a time domain potential flow *** model was initially validated by comparing it with published experimental and numerical computational fluid dynamics *** current results were in good agreement with the published *** was found that the energy extraction increased in the range of 6%to 17%during the evaluation of the effectiveness of the NSM in regular *** irregular wave conditions,specifically at the design wave conditions for the selected test site,the energy extraction increased by 2.4%,with annual energy production increments of approximately *** findings highlight the potential of NSM in enhancing the performance of asymmetric WEC devices,indicating more efficient energy extraction under various wave conditions.

关键词： asymmetric wave energy converter negative stiffness mechanism weakly nonlinear potential flow power

Prognostic impact of preoperative nutritional and immune inflammatory parameters on liver cancer

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World Journal of Gastrointestinal Surgery 2024年第2期16卷 266-269页

作者： Sung Uk bae Department of Surgery School of MedicineDongsan Medical CenterKeimyung UniversityDaegu KS002South Korea

The immune response to tissue damage or infection involves inflammation,a multifaceted biological process distinguished by immune cell activation,mediator secretion,and immune cell recruitment to the site of *** blood-based immune-inflammatory biomarkers with prognostic significance in malignancies have been *** this issue of the World Journal of Gastrointestinal Surgery,they examined the prognosis of liver cancer radical resection in relation to pre-operative systemic immune-inflammation and nutritional risk *** older and younger individuals often reveals compromised nutritional and immu-nological statuses in the ***,performing preoperative evaluations of the nutritional status and immunity in geriatric patients is *** addition to being a primary treatment modality,radical resection is associated with a sig-nificant mortality rate following *** dietary consump-tion and an elevated metabolic rate within tumor cells contribute to the increased proba-bility of malnutrition associated with the ailment,consequently leading to a sub-stantial deterioration in *** studies,reinforce the importance of nu-tritional and immune-inflammatory *** to surgical intervention,geriatric nutritional risk and systemic immune-inflammatory indices should be prioritized,particularly in older patients with malignant diseases.

关键词： Systemic immune inflammation index Nutritional risk index Radical resection Liver cancer Prognosis Correlation

CD200Rhigghh neutrophils with dysfunctional autophagy establish systemic immunosuppression by increasing regulatory T cells

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Cellular & Molecular Immunology 2024年第4期21卷 349-361页

作者： Ye Seon Kim Yu Sun Jeong Geon Ho bae Ji Hyeon Kang Mingyu Lee Brian A.Zabel Yoe-Sik bae Department of Biological Sciences Sungkyunkwan UniversitySuwon16419Republic of Korea Department of Health Science and Technology SAIHSTSungkyunkwan UniversitySeoul06351Republic of Korea Palo Alto Veterans Institute for Research Veterans Affairs HospitalPalo AltoCA94304USA

Distinct neutrophil populations arise during certain pathological *** generation of dysfunctional neutrophils during sepsis and their contribution to septicemia-related systemic immune suppression remain *** this study,using an experimental sepsis model that features immunosuppression,we identified a novel population of pathogenic CD200R^(high) neutrophils that are generated during the initial stages of sepsis and contribute to systemic immune suppression by enhancing regulatory T(T_(reg))*** to their CD200R^(low)counterparts,sepsis-generated CD200Rhigh neutrophils exhibit impaired autophagy and dysfunction,with reduced chemotactic migration,superoxide anion production,and TNF-α*** soluble CD200 blocks autophagy and neutrophil maturation in the bone marrow during experimental sepsis,and recombinant CD200 treatment in vitro can induce neutrophil dysfunction similar to that observed in CD200R^(high) *** administration of anα-CD200R antibody effectively reversed neutrophil dysfunction by enhancing autophagy and protecting against a secondary infection challenge,leading to increased *** analysis revealed that CD200R^(high) neutrophils expressed high levels of Igf1,which elicits the generation of Treg cells,while the administration of anα-CD200R antibody inhibited Treg cell generation in a secondary infection *** together,our findings revealed a novel CD200R^(high) neutrophil population that mediates the pathogenesis of sepsis-induced systemic immunosuppression by generating Treg cells.

关键词： Sepsis Neutrophils CD200R Autophagy IGF-1 Regulatory T cells