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Coupling CO_(2)reduction with ethane aromatization for enhancing catalytic stability of iron-modified ZSM-5

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Journal of Energy Chemistry 2022年第3期31卷 210-217,I0007页

作者： Zhenhua Xie Elaine Gomez Dong Wang ji hoon lee Tiefeng Wang jingguang G.Chen Department of Chemical Engineering Columbia UniversityNew YorkNY 10027USA Chemistry Division Brookhaven National LaboratoryUptonNY 11973USA Department of Chemical Engineering Tsinghua UniversityBeijing100084 BeijingChina

The shale gas revolution and the carbon-neutrality goal are motivating the landscape toward the synthesis of value-added chemicals or fuels from underutilized ethane with the assistance of greenhouse gas CO_(2).Combining ethane aromatization with CO_(2)reduction offers an opportunity to directly produce liquid products for facile separation,storage,and transportation.In the present work,Fe/ZSM-5 catalysts showed promise in the simultaneous CO_(2)reduction and ethane aromatization at atmospheric pressure and 873 K.The catalysts were further investigated using X-ray diffraction(XRD)and X-ray absorption fine structure(XAFS)measurements under in-situ conditions,indicating that most of Fe species existed in the form of Fe oxides and a portion of Fe was incorporated into the ZSM-5 framework generating Lewis acid sites.Both types of Fe species remained almost unchanged under reaction conditions,contributing to an enhanced aromatization activity of Fe/ZSM-5.The effects of CO_(2)and steam on the acid sites and in turn aromatization activity were also investigated by transient studies,which exhibited a reversible modification behavior.Moreover,CO_(2)was identified to be critical to enhance coke resistance and in turn catalyst stability.This work highlights the feasibility of using CO_(2)to assist the upgrading of abundant ethane from shale gas to aromatics over non-precious Fe-based zeolite catalysts.

关键词： Ethane CO_(2) Aromatization Fe-modified ZSM-5

Identification and comparison of the local physicochemical structures of transition metal-based layered double hydroxides for high performance electrochemical oxygen evolution reactions

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Journal of Energy Chemistry 2023年第12期87卷 89-97,I0004页

作者： Min Sung Kim Bipin Lamichhane Ju-Hyeon lee jin-Gyu Bae Jeong Yeon Heo Hyeon Jeong lee Shyam Kattel ji hoon lee School of Materials Science and Engineering Kyungpook National UniversityDaegu 41566Republic of Korea KNU Advanced Material Research Institute Kyungpook National UniversityDaegu 41566Republic of Korea Department of Materials Science and Engineering Ulsan National Institute of Science and TechnologyUlsan 44919Republic of Korea Department of Physics Florida A&M UniversityTallahasseeFlorida 32307United States

Layered double hydroxides(LDHs) have attracted considerable attention as a cost effective alternative to the precious iridium-and ruthenium-based electrocatalysts for an oxygen evolution reaction(OER),a bottleneck of water electrolysis for sustainable hydrogen production.Despite their excellent OER performance,the structural and electronic properties of LDHs,particularly during the OER process,remain to be poorly understood.In this study,a series of LDH catalysts is investigated through in situ X-ray absorption fine structure analyses and density functional theory(DFT) calculations.Our experimental results reveal that the LDH catalyst with equal amounts of Ni and Fe(NF-LDH) exhibits the highest OER activity and catalytic life span when compared with its counterparts having equal amounts of Ni and Co(NC-LDH)and Ni only(Ni-LDH).The NF-LDH shows a markedly enhanced OER kinetics compared to the NC-LDH and the Ni-LDH,as proven by the lower overpotentials of 180,240,and 310 mV,respectively,and the Tafel slopes of 35.1,43.4,and 62.7 mV dec^(-1),respectively.The DFT calculations demonstrate that the lowest overpotential of the NF-LDH is associated with the active sites located at the edge planes of NF-LDH in contrast to those located at the basal planes of Ni-LDH and NC-LDH.The current study pinpoints the active sites on various LDHs and presents strategies for optimizing the OER performance of the LDH catalysts.

关键词： Layered double hydroxides Oxygen evolution reaction In situ X-ray analyses Density functional theory Catalytic active sites

Ternary layered double hydroxide oxygen evolution reaction electrocatalyst for anion exchange membrane alkaline seawater electrolysis

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Journal of Energy Chemistry 2022年第12期75卷 127-134,I0004页

作者： Yoo Sei Park Jae-Yeop Jeong Myeong Je Jang Chae-Yeon Kwon Geul Han Kim Jaehoon Jeong ji-hoon lee Jooyoung lee Sung Mook Choi Department of Hydrogen Energy Materials Surface&Nano Materials DivisionKorea Institute of Materials Science(KIMS)Changwon 51508Republic of Korea Department of Advanced Material Engineering Chungbuk National University1 Chungdae-roSeowon-guCheongjuChungbuk 28644Republic of Korea Department of Chemical Engineering University of WaterlooWaterlooOntario N2L 3G1 Canada School of Materials Science and Engineering Gyeongsang National UniversityJinju 52828Republic of Korea Department of Materials Science and Engineering Pusan National UniversityBusan 46241Republic of Korea Energy Industry Support Center Daegu Mechatronics&Materials InstituteDaegu 42704Republic of Korea Advanced Materials Engineering University of Science and Technology(UST)Yuseong-guDaejeon 34113Republic of Korea

Anion exchange membrane(AEM)water electrolyzers are promising energy devices for the production of clean hydrogen from seawater.However,the lack of active and robust electrocatalysts for the oxygen evolution reaction(OER)severely impedes the development of this technology.In this study,a ternary layered double hydroxide(LDH)OER electrocatalyst(NiFeCo-LDH)is developed for high-performance AEM alkaline seawater electrolyzers.The AEM alkaline seawater electrolyzer catalyzed by the NiFeCo LDH shows high seawater electrolysis performance(0.84 A/cm^(2)at 1.7 Vcell)and high hydrogen production efficiency(77.6%at 0.5 A/cm^(2)),thus outperforming an electrolyzer catalyzed by a benchmark IrO_(2)electrocatalyst.The NiFeCo-LDH electrocatalyst greatly improves the kinetics of the AEM alkaline seawater electrolyzer,consequently reducing its activation loss and leading to high performance.Based on the results,this NiFeCo-LDH-catalyzed AEM alkaline seawater electrolyzer can likely surpass the energy conversion targets of the US Department of Energy.

关键词： Anion exchange membranes water electrolysis Oxygen evolution reactions Alkaline seawater electrolysis Hydrogen production

Synthesis and electrocatalytic applications of flower-like motifs and associated composites of nitrogen-enriched tungsten nitride(W2N3)

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Nano Research 2020年第5期13卷 1434-1443页

作者： Sha Tan Brian M.Tackett Qun He ji hoon lee jingguang G.Chen Stanislaus S.Wong Department of Chemistry State University of New York at Stony BrookStony BrookNY 11794-3400USA Department of Chemical Engineering Columbia UniversityNew YorkNY 10027USA Chemistry Department Building 555Brookhaven National LaboratoryUptonNY 11973USA

We have sought to improve the electrocatalytic performance of tungsten nitride through synthetic control over chemical composition and morphology.In particular,we have generated a thermodynamically unstable but catalytically promising nitrogen-rich phase of tungsten via a hydrothermal generation of a tungsten oxide intermediate and subsequent annealing in ammonia.The net product consisted of three-dimensional(3D)micron-scale flower-like motifs of W2N3;this architecture not only evinced high structural stability but also incorporated the favorable properties of constituent two-dimensional nanosheets.From a performance perspective,as-prepared 3D W2N3 demonstrated promising hydrogen evolution reaction(HER)activities,especially in an acidic environment with a measured overpotential value of−101 mV at a current density of 10 mA/cm^2.To further enhance the electrocatalytic activity,small amounts of precious metal nanoparticles(such as Pt and Au),consisting of variable sizes,were uniformly deposited onto the underlying 3D W2N3 motifs using a facile direct deposition method;these composites were applied towards the CO2 reduction reaction(CO2RR).A highlight of this series of experiments was that Au/W2N3 composites were found to be a much more active HER(as opposed to either a CO2RR or a methanol oxidation reaction(MOR))catalyst.

关键词： tungsten nitride synthesis composite morphology control electrocatalysis

CYP3A5 unexpectedly regulates glucose metabolism through the AKT-TXNIP-GLUT1 axis in pancreatic cancer

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Genes & Diseases 2024年第4期11卷 381-399页

作者： Ming Shao Qingfei Pan Haiyan Tan jing Wu Ha Won lee Andrew D.Huber William C.Wright ji-hoon Cho jiyang Yu Junmin Peng Taosheng Chen Department of Chemical Biology and Therapeutics St.Jude Children's Research HospitalMemphisTN 38105USA Department of Computational Biology St.Jude Children's Research HospitalMemphisTN 38105USA Center for Proteomics and Metabolomics St.Jude Children's Research HospitalMemphisTN 38105USA Department of Structural Biology St.Jude Children's Research HospitalMemphisTN 38105USA Department of Developmental Neurobiology St.Jude Children's Research HospitalMemphisTN 38105USA

CYP3A5 is a cytochrome P450(CYP)enzyme that metabolizes drugs and contributes to drug resistance in cancer.However,it remains unclear whether CYP3A5 directly influences cancer progression.In this report,we demonstrate that CYP3A5 regulates glucose metabolism in pancreatic ductal adenocarcinoma.Multi-omics analysis showed that CYP3A5 knockdown re-sults in a decrease in various glucose-related metabolites through its effect on glucose trans-port.A mechanistic study revealed that CYP3A5 enriches the glucose transporter GLUT1 at the plasma membrane by restricting the translation of TXNIP,a negative regulator of GLUT1.Notably,CYP3A5-generated reactive oxygen species were proved to be responsible for atten-uating the AKT-4EBP1-TXNIP signaling pathway.CYP3A5 contributes to cell migration by maintaining high glucose uptake in pancreatic cancer.Taken together,our results,for the first time,reveal a role of CYP3A5 in glucose metabolism in pancreatic ductal adenocarcinoma and identify a novel mechanism that is a potential therapeutic target.

关键词： Cell migration CYP3A5 Glucose metabolism GLUT1 Pancreatic cancer TXNIP

Mixed-dimensional stacked nanocomposite structures for a specific wavelength-selectable ambipolar photoresponse

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Nano Research 2024年第6期17卷 5549-5558页

作者： Young Jae Park Jaeho Shim Joo Song lee Kyu Seung lee ji-Yeon Kim Kang Bok Ko Sang-Youp Yim Seongjun Kim hoon-Kyu Shin Donghee Park Yong Ju Yun Dong Ick Son Institute of Advanced Composite Materials Korea Institute of Science and TechnologyJeollabuk-do 55324Republic of Korea National Institute for Nanomaterials Technology Pohang University of Science and TechnologyGyeongsangbuk-do 37673Republic of Korea Department of Semiconductor Science and Technology Semiconductor Physics Research CenterJeonbuk National UniversityJeonju 54896Republic of Korea Advanced Photonics Research Institute Gwangju Institute of Science and TechnologyGwangju 61005Republic of Korea Center for Opto-Electronic Materials and Devices Post-Silicon Semiconductor InstituteKorea Institute of Science and TechnologySeoul 02792Republic of Korea Graduate School of Energy and Environment(KU-KIST Green School) Korea UniversitySeoul 02841Republic of Korea KIST School Department of Nanomaterials and Nano ScienceUniversity of Science and Technology(UST)Daejeon 34113Republic of Korea

Mixed-dimensional composite structures using zero-dimensional(0D)quantum dots(QDs)and two-dimensional(2D)transition metal dichalcogenides(TMDs)materials are expected to attract great interest in optoelectronics due to the potential to generate new optical properties.Here,we report on the unique optical characteristics of a devices with mixed dimensional vertically stacked structures based on tungsten diselenide(WSe_(2))/CdSeS QDs monolayer/molybdenum disulfide(MoS_(2))(2D/0D/2D).Specifically,it exhibits an ambipolar photoresponse characteristic,with a negative photoresponse observed in the 400-600 nm wavelength range and a positive photoresponse appeared at 700 nm wavelength.It resulted in the high negative responsivity of up to 52.22 mA·W^(−1)under 400 nm,which is 163 times higher than that of the photodetector without CdSeS QDs.We also demonstrated the negative photoresponse,which could be due to increased carrier collision probability and non-radiative recombination.Device modeling and simulation reveal that Auger recombination among the types of non-radiative recombination is the main cause of negative photocurrent generation.Consequently,we discovered ambipolar photoresponse near a specific wavelength corresponding to the energy of quantum dots.Our study revealed interesting phenomenon in the mixed low-dimensional stacked structure and paved the way to exploit it for the development of innovative photodetection materials as well as for optoelectronic applications.

关键词： mixed-dimension quantum dot heterostructure photodetector ambipolar photoresponse

Nusinersen for spinal muscular atrophy types Ⅱ and Ⅲ:a retrospective single-center study in South Korea

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World Journal of Pediatrics 2023年第5期19卷 450-459页

作者： Hui jin Shin ji-hoon Na Hyunjoo lee Young-Mock lee Department of Pediatrics Gangnam Severance HospitalYonsei University College of Medicine211 Eonju-RoGangnam-GuSeoul135-720Korea

Background This study investigated the efficacy and safety of nusinersen,an antisense oligonucleotide,in patients with spinal muscular atrophy(SMA)types II(OMIM:253,550)or III(OMIM:253,400),including those with severe scoliosis or requiring respiratory support via mechanical ventilation.Methods Data from 40 patients with genetically confirmed SMA who were treated with nusinersen at our institute from March 2019 to April 2022 were retrospectively analyzed.Of these,30 patients with an age of onset<3 years and not on permanent ventilation were selected.Clinical and genetic characteristics were investigated,and motor function was evaluated based on the Hammersmith Functional Motor Scale-Expanded(HFMSE)score.Results The mean age of symptom onset was 1.2 years.Most patients were diagnosed with SMA type II(27/30,90%).Nusinersen was administered via computed tomography-guided or direct intrathecal injection in 87%(26/30)and 13%(4/30)of the patients,respectively.At the 6-,14-,22-,and 26-month follow-ups,72%,71%,88%,and 86%of patients showed motor improvement,respectively,with mean changes in HFMSE scores of 2.10,2.88,4.21,and 5.29,respectively.Multivariable analysis showed that the use of noninvasive ventilation was associated with poorer outcomes of motor function.Conclusions Patients with SMA type II or III who received nusinersen treatment showed significant improvement in motor function.A longer treatment duration led to a higher number of patients with improved motor function.No significant side effects of nusinersen were observed.Patients with SMA,even those with severe scoliosis or on respiratory support,can be safely treated using nusinersen.

关键词： Hammersmith Functional Motor Scale Expanded Motor function Nusinersen South Korea Spinal muscular atrophy

Jacobsen syndrome with bilateral periventricular white matter lesions

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World Journal of Pediatrics 2022年第2期18卷 142-143页

作者： Hyun-Joo lee Hae-ln lee ji-hoon Na Young-Mock lee Department of Pediatrics Yonsei University College of MedicineSeoulKorea Department of Pediatrics Gangnam Severance HospitalYonsei University College of Medicine21Eonju-roGangnam-guSeoul 06273Korea

A 2-month-old girl presented facial dimorphism,including frontal bossing,hypertelorism,a broad nasal bridge,low-set ears,hypotonia with mild spasticity,and mild thrombocytopenia.Her head circumference was 40.8 cm(75-9... 详细信息

关键词： white ism Jacobsen

Parameterization of below-cloud scavenging for polydisperse fine mode aerosols as a function of rain intensity

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Journal of Environmental Sciences 2023年第10期132卷 43-55页

作者： Chang hoon Jung Hyung-Min lee Dasom Park Young Jun Yoon Yongjoo Choi Junshik Um Seoung Soo lee ji Yi lee Yong Pyo Kim Department of Health Management Kyungin Women’s UniversityIncheon 21041Korea Department of Environmental Science and Engineering Ewha Woman’s UniversitySeoulKorea Department of Environmental Engineering Konkuk UniversitySeoulKorea Korea Polar Research Institute IncheonKorea Department of Environment Hankuk University of Foreign StudiesYonginKorea Department of Atmospheric Sciences Pusan National UniversityBusanKorea Earth System Science Interdisciplinary Center University of MarylandCollege ParkMDUSA Research Center for Climate Sciences Pusan National UniversityBusanKorea Department of Chemical Engineering and Materials Science Ewha Womans UniversitySeoulKorea

The below-cloud aerosol scavenging process by precipitation is one of the most important mechanisms to remove aerosols from the atmosphere.Due to its complexity and dependence on both aerosol and raindrop sizes,wet scavenging process has been poorly treated,especially during the removal of fine particles.This makes the numerical simulation of below-cloud scavenging in large-scale aerosolmodels unrealistic.To consider the slip effects of submicron particles,a simplified expression for the diffusion scavenging was developed by approximating the Cunningham slip correction factor.The derived analytic solution was parameterized as a simple power function of rain intensity under the assumption of the lognormal size distribution of particles.The resultant approximated expression was compared to the observed data and the results of previous studies including a 3D atmospheric chemical transport model simulation.Compared with the default GEOS-Chem coefficient of 0.00106R0.61 and the observation-based coefficient of 0.0144R0.9268,the coefficient of a and b in∧m=aRb spread in the range of 0.0002-0.1959 for a and 0.3261-0.525 for b over a size distribution of GSD of 1.3–2.5 and a geometric mean diameter of 0.01-2.5μm.Overall,this study showed that the scavenging coefficient varies widely by orders of magnitude according to the size distribution of particles and rain intensity.This study also demonstrated that the obtained simplified expression could consider the theoretical approach of aerosol polydispersity.Our proposed analytic approach showed that results can be effectively applied for reduced computational burden in atmospheric modeling.

关键词： Below-cloud scavenging Polydisperse aerosol Parameterization Cunningham correction factor Scavenging coefficient