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Biochar-based materials as remediation strategy in petroleum hydrocarbon-contaminated soil and water:Performances,mechanisms,and environmental impact

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Journal of Environmental Sciences 2024年第4期138卷 350-372页

作者： Zhuo Wei YiWei Yang Liu Shuai Niu Yaxi Xu Jong-hwan Park Jim J.wang Faculty of Environmental Science&Engineering Kunming University of Science&TechnologyKunming 650500China School of Plant Environment&Soil SciencesLouisiana State University AgCenter.Baton RougeLA 70803USA Department of Life Resources Industry Dong-A University37Nakdong-daero 550 beon-gilSaha-guBusan 49315South Korea

Petroleum contamination is considered as a major risk to the health of humans and environment.Biochars as low-cost and eco-friendly carbon materials,have been widely used for the removal of petroleum hydrocarbon in the environment.The purpose of this paper is to review the performance,mechanisms,and potential environmental toxicity of biochar,modified biochar and its integration use with other materials in petroleum contaminated soil and water.Specifically,the use of biochar in oil-contaminated water and soil as well as the factors that could influence the removal ability of biochar were systematically evaluated.In addition,the modification and integrated use of biochar for improving the removal efficiency were summarized from the aspects of sorption,biodegradation,chemical degradation,and reusability.Moreover,the functional impacts and associated ecotoxicity of pristine and modified biochars in various environments were demonstrated.Finally,some shortcoming of current approaches,and future research needs were provided for the future direction and challenges of modified biochar research.Overall,this paper gain insight into biochar application in petroleum remediation from the perspectives of performance enhancement and environmental sustainability.

关键词： Petroleum contamination Adsorbent Bioremediation Biochar modification Ecotoxicity

Vertical plane depth-resolved surface potential and carrier separation characteristics in flexible CZTSSe solar cells with over 12% efficiency

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Carbon Energy 2024年第3期6卷 36-52页

作者： Dae-Ho Son Ha Kyung Park Dae-hwan Kim Jin-Kyu Kang Shi-Joon Sung Dae-Kue hwang Jaebaek Lee dong-hwan Jeon Yunae Cho William Jo Taeseon Lee JunHo Kim Sang-Hoon Nam Kee-Jeong Yang Division of Energy Technology DGISTDaeguRepublic of Korea Research Center for Thin Film Solar Cells DGISTDaeguRepublic of Korea Department of Physics Ewha Womans UniversitySeoulRepublic of Korea Department of Physics Incheon National UniversityIncheonRepublic of Korea Department of Mechanical Engineering Massachusetts Institute of TechnologyCambridgeMassachusettsUSA

Cu2ZnSn(S,Se)4(CZTSSe)solar cells have resource distribution and economic advantages.The main cause of their low efficiency is carrier loss resulting from recombination of photo-generated electron and hole.To overcome this,it is important to understand their electron-hole behavior characteristics.To determine the carrier separation characteristics,we measured the surface potential and the local current in terms of the absorber depth.The elemental variation in the intragrains(IGs)and at the grain boundaries(GBs)caused a band edge shift and bandgap(Eg)change.At the absorber surface and subsurface,an upward Ec and Ev band bending structure was observed at the GBs,and the carrier separation was improved.At the absorber center,both upward Ec and Ev and downward Ec-upward Ev band bending structures were observed at the GBs,and the carrier separation was degraded.To improve the carrier separation and suppress carrier recombination,an upward Ec and Ev band bending structure at the GBs is desirable.

关键词： carrier separation CZTSSe flexible solar cell local current surface potential

Phylogenetic relationship,biogeography,and conservation genetics of endangered Fraxinus chiisanensis(Oleaceae),endemic to South Korea

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Plant Diversity 2022年第2期44卷 170-180页

作者： Changkyun Kim dong-Kap Kim Hang Sun Joo-hwan Kim Plant Research Division Honam National Institute of Biological ResourcesMokpo 58762Republic of Korea Forest Biodiversity Division Korea National ArboretumPocheon 11186Republic of Korea CAS Key Laboratory for Plant Biodiversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of SciencesKunming 650204YunnanPR China Department of Life Science Gachon UniversitySeongnam 13120Republic of Korea

Endemic plants are important for understanding phylogenetic relationships,biogeographical history,and genetic variation because of their restricted distribution and their role in conserving biodiversity.Here,we investigated the phylogenetic relationships of the Korean endemic Fraxinus chiisanensis by reconstructing the molecular phylogeny of Fraxinus based on two nuclear DNA(nrITS and phantastica)and two chloroplast DNA(psbA-trnH and rp132-trnL)regions.Within our fossil-calibrated phylogenetic framework,we also inferred the biogeographical history of F.chiisanensis.To provide a scientific basis for the conservation of F.chiisanensis,we determined the levels of genetic diversity and genetic differentiation in this species.Combining information from nuclear and chloroplast DNA sequence data,our molecular phylogenetic analyses identified F.chiisanensis as a genetically distinct unit from its sister group,Fraxinus platypoda from Japan.Our molecular dating analyses using nuclear and chloroplast DNA data sets show F.chiisanensis diverged from its sister F.platypoda in the Early or Middle Miocene and differentiated in the Late Miocene on the Korean Peninsula.Our results suggest that the divergence of F.chiisanensis was associated with the submergence of the East China Sea land bridge and enhanced monsoons in East Asia.When compared to F.platypoda,F.chiisanensis exhibits low genetic diversity within populations and high genetic differentiation among populations.These results help us to understand the evolutionary history of F.chiisanensis and to develop a conservation strategy for this species.

关键词： East China Sea land bridge Endemic species Fraxinus chiisanensis Korean Peninsula Genetic diversity Biogeography

A surgical technique using the gastroepiploic vein for portal inflow restoration in living donor liver transplantation in a patient with diffuse portomesenteric thrombosis

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国际肝胆胰疾病杂志:英文版 2023年第5期22卷 537-540页

作者： Sang-Hoon Kim Deok-Bog Moon Woo-Hyoung Kang dong-hwan Jung Sung-Gyu Lee Division of Hepatobiliary Surgery and Liver Transplantation Department of SurgeryAsan Medical Center and University of Ulsan College of Medicine88 Olympic-ro 43-gilSongpa-guSeoul 05505Korea

Portal vein thrombosis(PVT)is no longer a definitive contraindication in liver transplants(LTs)[1].Complex vascular reconstructions such as cavoportal hemitransposition(CPHT)[2–5],renoportal anastomosis(RPA)[6,7],and use of sizable collaterals(pericholedochal varix[8,9],coronary vein,peripancreatic or perigastroesophageal varices[10],right superior colic vein[11],ileocolic vein[12],and left gastric vein[13]),or combined liverpancreas-small bowel transplant[14]are required for portal inflow in patients with total portosplenomesenteric thrombosis.

关键词： thrombosis anastomosis portal

Importance of Adaptive Photometric Augmentation for Different Convolutional Neural Network

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Computers, Materials & Continua 2022年第9期72卷 4433-4452页

作者： Saraswathi Sivamani Sun Il Chon Do Yeon Choi dong Hoon Lee Ji hwan Park AI Reliability Lab ThinkforBL Consultancy ServicesGangnamSeoulKorea Department of Biosystems Engineering Chungbuk National UniversityCheongju-siChungcheongbuk-do28644Korea

Existing segmentation and augmentation techniques on convolutional neural network(CNN)has produced remarkable progress in object detection.However,the nominal accuracy and performance might be downturned with the photometric variation of images that are directly ignored in the training process,along with the context of the individual CNN algorithm.In this paper,we investigate the effect of a photometric variation like brightness and sharpness on different CNN.We observe that random augmentation of images weakens the performance unless the augmentation combines the weak limits of photometric variation.Our approach has been justified by the experimental result obtained from the PASCAL VOC 2007 dataset,with object detection CNN algorithms such as YOLOv3(You Only Look Once),Faster R-CNN(Region-based CNN),and SSD(Single Shot Multibox Detector).Each CNN model shows performance loss for varying sharpness and brightness,ranging between−80%to 80%.It was further shown that compared to random augmentation,the augmented dataset with weak photometric changes delivered high performance,but the photometric augmentation range differs for each model.Concurrently,we discuss some research questions that benefit the direction of the study.The results prove the importance of adaptive augmentation for individual CNN model,subjecting towards the robustness of object detection.

关键词： Object detection photometric variation adaptive augmentation convolutional neural network

High-Performance Perovskite Quantum Dot Solar Cells Enabled by Incorporation with Dimensionally Engineered Organic Semiconductor

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Nano-Micro Letters 2022年第12期14卷 272-285页

作者： Seyeong Lim Dae hwan Lee Hyuntae Choi Yelim Choi dong Geon Lee Sung Beom Cho Seonkyung Ko Jongmin Choi Younghoon Kim Taiho Park Department of Chemical Engineering Pohang University of Science and Technology(POSTECH)Pohang 37673Republic of Korea Department of Materials Science and Engineering Hanyang UniversitySeoul 04763Republic of Korea Center of Materials Digitalization Korea Institute of Ceramic Engineering and Technology(KICET)Jinju 52851Republic of Korea Department of Materials Science and Engineering Ajou UniversitySuwon 16499Republic of Korea Department of Energy Science and Engineering Daegu Gyeongbuk Institute of Science and Technology(DGIST)Daegu 42988Republic of Korea Department of Chemistry Kookmin UniversitySeoul 02707Republic of Korea

Perovskite quantum dots(PQDs)have been considered promising and effective photovoltaic absorber due to their superior optoelectronic properties and inherent material merits combining perovskites and QDs.However,they exhibit low moisture stability at room humidity(20-30%)owing to many surface defect sites generated by inefficient ligand exchange process.These surface traps must be re-passivated to improve both charge transport ability and moisture stability.To address this issue,PQD-organic semiconductor hybrid solar cells with suitable electrical properties and functional groups might dramatically improve the charge extraction and defect passivation.Conventional organic semiconductors are typically low-dimensional(1D and 2D)and prone to excessive self-aggregation,which limits chemical interaction with PQDs.In this work,we designed a new 3D star-shaped semiconducting material(Star-TrCN)to enhance the compatibility with PQDs.The robust bonding with Star-TrCN and PQDs is demonstrated by theoretical modeling and experimental validation.The Star-TrCN-PQD hybrid films show improved cubic-phase stability of CsPbI_(3)-PQDs via reduced surface trap states and suppressed moisture penetration.As a result,the resultant devices not only achieve remarkable device stability over 1000 h at 20-30%relative humidity,but also boost power conversion efficiency up to 16.0%via forming a cascade energy band structure.

关键词： CsPbI3 quantum dots Star-shaped organic semiconductors Hybrid perovskite quantum dots Solar cell stability High-efficiency photovoltaics

Study of engineering electronic structure modulated non-noble metal oxides for scaled-up alkaline blend seawater splitting

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Journal of Energy Chemistry 2023年第11期86卷 167-179,I0004页

作者： Natarajan Logeshwaran Subramanian Vijayapradeep Ae Rhan Kim Prabhakaran Sampath Shanmugam Ramakrishnan Milan Babu Poudel Do hwan Kim dong Jin Yoo Graduate School Department of Energy Storage/Conversion Engineering(BK21 FOUR)Hydrogen and Fuel Cell Research CenterJeonbuk National University567-Baekje-daeroDeokjin-guJeonju-siJeollabuk-do 54896Republic of Korea Department of Life Science Jeonbuk National University567-Baekje-daeroDeokjin-guJeonju-siJeollabuk-do 54896Republic of Korea Division of Science Education and Institute of Fusion Science Jeonbuk National University567-Baekje-daeroDeokjin-guJeonju-siJeollabuk-do 54896Republic of Korea Department of Nano Convergence Engineering Jeonbuk National University567-Baekje-daeroDeokjin-guJeonju-siJeollabuk-do 54896Republic of Korea School of Engineering Merz CourtNewcastle UniversityNE17RUUnited Kingdom

Scaled-up industrial water electrolysis equipment that can be used with abundant seawater is key for affordable hydrogen production.The search for highly stable,dynamic,and economical electrocatalysts could have a significant impact on hydrogen commercialization.Herein,we prepared energy-efficient,scalable,and engineering electronic structure modulated Mn-Ni bimetal oxides(Mn_(0.25)Ni_(0.75)O)through simple hydrothermal followed by calcination method.As-optimized Mn_(0.25)Ni_(0.75)O displayed enhanced oxygen and hydrogen evolution reaction(OER and HER)performance with overpotentials of 266 and115 mV at current densities of 10 mA cm^(-2)in alkaline KOH added seawater electrolyte solution.Additionally,Mn-Ni oxide catalytic benefits were attributed to the calculated electronic configurations and Gibbs free energy for OER,and HER values were estimated using first principles calculations.In real-time practical application,we mimicked industrial operating conditions with modified seawater electrolysis using Mn_(0.25)Ni_(0.75)O‖Mn_(0.25)Ni_(0.75)O under various temperature conditions,which performs superior to the commercial IrO_(2)‖Pt-C couple.These findings demonstrate an inexpensive and facile technique for feasible large-scale hydrogen production.

关键词： Waterel ectrolysis Mn-Ni oxide complex Chlorine evolution reaction Industrial seawater operations Density functional theory calculations

Texture development and grain boundary phase formation in Ce-and Ce-La-substituted Nd-Fe-B magnets during hot-deformation process

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Journal of Materials Science & Technology 2022年第31期126卷 71-79页

作者： Ga-Yeong Kim Tae-Hoon Kim Hee-Ryoung Cha Sang-hyub Lee dong-hwan Kim Yang-Do Kim Jung-Goo Lee Department of Magnetic Materials Korea Institute of Materials ScienceChangwon 51508Republic of Korea Department of Materials Science and Engineering Pusan National UniversityBusan 46241Republic of Korea R&D Center Star Group Ind.Co.Ltd.Daegu 42714Republic of Korea

In this study,the influence of Ce-and Ce-La-substitution for Nd in Nd-Fe-B magnets on their magnetic and microstructural changes in the course of the hot-deformation process was investigated to gain insight into further reducing the Nd content in fine-grained Nd-Fe-B hot-deformed magnets.We found that the[001]texture and microstructure of the RE-rich grain boundary phases,which are the factors that de-termine the remanence and coercivity of hot-deformed magnets,were deteriorated by the Ce-and Ce-La-substitution.This is because the volume fraction of the RE-rich liquid formed in the grain boundaries during the hot-press and hot-deformation decreased due to the Ce-and Ce-La-substitution,thereby in-creasing the friction between the 2:14:1 grains while the c-axes of grains were aligned by grain rotation and decreasing the RE concentration of grain boundary phases.In particular,the Ce-La-co-substitution further prevented the liquid formation within the grain boundaries of the magnets during hot-press and hot-deformation because the wettability of the RE-rich liquid on the 2:14:1 grains became poor when La was substituted for Nd in the 2:14:1 grains.These results indicate that there is room for further im-provement in both the remanence and coercivity of the Ce-and Ce-La-substituted magnets by intro-ducing additional liquid into the grain boundaries prior to hot-press and hot-deformation.By applying the Nd-Cu infiltration process to the melt-spun ribbons(intermediate infiltration,I-infiltration),both the remanence and coercivity of the Nd-saving(Nd 0.7 Ce 0.3)-Fe-B and(Nd 0.7 Ce 0.225 La 0.075)-Fe-B hot-deformed magnets were successfully improved.

关键词： Nd-Fe-B magnets Hot-deformation Nd-saving Ce-substitution La-substitution Infiltration

Intraoperative sudden arrhythmias in cervical spine surgery adjacent to the stellate ganglion:A case report

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世界临床病例杂志 2023年第24期11卷 5789-5796页

作者： Jong-Hun Seo Su-Yeon Cho Ji-hwan Park Jin-Young Seo Hyun-Young Lee dong-Joon Kim Department of Neurosurgery Chosun University HospitalGwangju 61453South Korea Department of Anesthesiology and Pain Medicine Chosun University HospitalGwangju 61453South Korea Department of Anesthesiology and Pain Medicine College of MedicineChosun UniversityGwangju 61453South Korea

BACKGROUND Atrial arrhythmias such as paroxysmal supraventricular tachycardia(PSVT)and atrial flutter(AF)are common in the perioperative setting.They commonly resolve spontaneously.However,occasionally,they may continually progress to fatal arrhythmias or cause complications.Therefore,prompt and appropriate management is important.CASE SUMMARY A 46-year-old female patient diagnosed with cervical C6-7 radiculopathy characterized by decreased sensation in the right third,fourth and fifth fingers underwent C6-7 anterior cervical disc fusion surgery.Electrocardiography showed PSVT and ventricular tachycardia during C6-7 disc retraction.However,the patient remained stable.Initial treatment with esmolol and lidocaine for ventricular tachycardia was ineffective.Carotid massage and Valsalva maneuver were attempted but PSVT did not resolve.The surgery was paused,and the patient’s fraction of inspired oxygen was set to 100%.Adenosine was administered for pharmacological management of PSVT.The arrhythmia temporarily resolved.However,it then transformed into AF.Diltiazem was administered,which briefly decreased blood pressure,which immediately recovered.Surgery resumed while the patient was in normal sinus rhythm.She was discharged safely on postoperative day 6 without complications or abnormalities.Currently,she is living a healthy life without arrhythmia recurrence.CONCLUSION Ganglia associated with cardiac arrhythmias in the surgical site should be identified during cervical spine surgery.

关键词： Supraventricular tachycardia Atrial flutter Stellate ganglion Adenosine Diltiazem Case Report