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journal of Magnesium and Alloys 2023年第11期11卷 4274-4281页

作者： jee Eun jang jihye Seong Soo-hyun joo Sung Hyuk Park School of Materials Science and Engineering Kyungpook National UniversityDaegu 41566Republic of Korea Department of Materials Science and Engineering Dankook UniversityCheonan 31116Republic of Korea

This study presents a novel process for the fabrication of metal-intermetallic composites with a 3D bicontinuous structure, achieved through a combination of liquid metal dealloying(LMD) and subsequent alloying. Initially, porous Ti structures are produced using the LMD process, followed by immersion in a molten Mg-3Al(wt%) metal. Due to the higher thermodynamic miscibility of Al with Ti compared to Mg, the concentration of Al in the Ti matrix increases as the immersion time increases. This results in a sequential phase transition within the Ti matrix: α-Ti → Ti_(3)Al → Ti Al. The phase transition considerably affects the hardness and strength of the composite material,with the Mg-Ti_(3)Al-Ti Al composite exhibiting a maximum hardness nearly twice as high as that of the conventional Mg-Ti composite. This innovative process holds potential for the development of various bicontinuous metal-intermetallic composites.

关键词： Liquid metal dealloying Subsequent alloying Metal–intermetallic composite 3D bicontinuous structure Hardness

Heat Transfer between Casting and Die during High Pressure Die Casting Process of AM50 Alloy-Modeling and Experimental Results

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journal of Materials Science & Technology 2008年第1期24卷 131-135页

作者： Zhipeng GUO Shoumei XIONG Sang-hyun Cho jeong-Kil Choi Key Laboratory for Advanced Manufacturing by Materials Processing Technology Department of Mechanical Engineering Tsinghua University Beijing 100084 China Advanced Material R＆D Center Korean Institute of Industrial Technology 994-32 Dongchun-Dong Yonsu-Ku Inchon Korea

A method based on die casting experiments and mathematic modeling is presented for the determination of the heat flow density （HFD） and interfacial heat transfer coefficient （IHTC） during the high pressure die casting （HPDC） *** were carried out using step shape casting and a commercial magnesium alloy,*** profiles were measured and recorded using thermocouples embedded inside the die. Based on these temperature readings,the HFD and IHTC were successfully determined and the calculation results show that the HFD and IHTC at the metal-die interface increases sharply right after the fast phase injection process until approaching their maximum values,after which their values decrease to a much lower level until the dies are *** patterns of heat transfer behavior were found between the die and the casting at different *** thinner the casting was,the more quickly the HFD and IHTC reached their steady ***,the values for both the HFD and IHTC values were different between die and casting at different thicknesses.

关键词： : Interfacial heat transfer coefficient High pressure die casting process AM50 Magnesium alloy

Applying robust design to study the effects of stratigraphic characteristics on brittle failure and bump potential in a coal mine

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International journal of Mining Science and Technology 2018年第1期28卷 137-144页

作者： Bo-hyun Kim Mark K.Larson Heather E.Lawson Spokane Mining Research Division NIOSH/CDC

Bumps and other types of dynamic failure have been a persistent, worldwide problem in the underground coal mining industry, spanning *** example, in just five states in the *** 1983 to 2014,there were 388 reportable *** significant advances in mine design tools and mining practices,these events continue to *** conditions have been associated with bump potential, such as the presence of stiff units in the local *** effect of a stiff sandstone unit on the potential for coal bumps depends on the location of the stiff unit in the stratigraphic column, the relative stiffness and strength of other structural members, and stress concentrations caused by *** study describes the results of a robust design to consider the impact of different lithologic risk factors impacting dynamic failure *** the inherent variability of stratigraphic characteristics in sedimentary formations,such as thickness, engineering material properties, and location, is significant and the number of influential parameters in determining a parametric study is large, it is impractical to consider every simulation case by varying each parameter ***, to save time and honor the statistical distributions of the parameters, it is necessary to develop a robust design to collect sufficient sample data and develop a statistical analysis method to draw accurate conclusions from the collected *** this study,orthogonal arrays, which were developed using the robust design, are used to define the combination of the(a) thickness of a stiff sandstone inserted on the top and bottom of a coal seam in a massive shale mine roof and floor,(b) location of the stiff sandstone inserted on the top and bottom of the coal seam,and(c) material properties of the stiff sandstone and contacts as interfaces using the 3-dimensional numerical model, *** completion of the numerical experiments, statistical and multivariate analysis are performed using

关键词： Bumps Robust design FLAC3D Plastic dissipated energy Multiple regression

Effect of pre-deformation on precipitation behavior of AZ80 alloy:Comparison of slip-and twinning-dominant deformation

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journal of Magnesium and Alloys 2024年第9期12卷 3616-3630页

作者： hyun ji Kim Sang Cheol jin Sumi jo Sung Hyuk Park Department of Materials Science and Metallurgical Engineering Kyungpook National UniversityDaegu 41566Republic of Korea Graduate School of Materials Science and Engineering Kyungpook National UniversityDaegu 41566Republic of Korea

This study investigates the effect of the deformation mode on the precipitation behavior of an extruded Mg-8.0Al-0.5Zn-0.2Mn(AZ80)*** alloy samples are compared after the application of 3.5%tension and 3.5%compression along the extrusion direction to induce slip-dominant and twinning-dominant deformation modes,*** pre-compressed(PC)sample,which contained numerous{10-12}tension twins,has a reduced grain size and a higher internal strain than the pre-tensioned(PT)sample,which is attributed to the inherent internal strain that occurs during the formation and growth of the *** a result,the precipitation behavior of the PC sample is accelerated,leading to its short peak aging time of 32 h,which is lower than those of the PT and as-extruded samples(48 and 100 h,respectively).Furthermore,fine continuous precipitates(CPs)rapidly form within the{10-12}twins,contributing to the enhanced *** precipitates(DPs),which have a hardness comparable to the CP-containing twinned regions,in the PC sample experience less coarsening during aging than those in the PT sample due to growth inhibition by the{10-12}***,the{10-12}twins generated under the twinning-dominant deformation condition lead to enhanced precipitation behaviors,including the preferential formation and refinement of CPs and the suppressed coarsening of ***,pre-deformation that occurs{10-12}twinning exhibits more pronounced effects on precipitation acceleration and microstructural modification than slip-inducing pre-deformation.

关键词： AZ80 alloy Slip Twinning Precipitation Hardness

Artificial synaptic and self-rectifying properties of crystalline(Na_(1-x)K_(x))NbO_(3)thin films grown on Sr_(2)Nb_(3)O_(10)nanosheet seed layers

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journal of Materials Science & Technology 2022年第28期123卷 136-143页

作者： In-Su Kim jong-Un Woo hyun-Gyu Hwang Bumjoo Kim Sahn Nahm Department of Materials Science and Engineering Korea UniversitySeoul 02841Republic of Korea KU-KIST Graduate School of Converging Science and Technology Korea UniversitySeoul 02841Republic of Korea

Crystalline(Na_(1-x)K_(x))NbO_(3)(NKN)thin films were deposited on Sr_(2)Nb_(3)O_(10)/TiN/Si(S-TS)substrates at 370°***_(2)Nb_(3)O_(10)(SNO)nanosheets served as a template for the formation of crystalline NKN films at low *** the NKN film was deposited on one SNO monolayer,the NKN memristor exhibited normal bipolar switching characteristics,which could be attributed to the formation and destruction of oxygen vacancy ***,the NKN memristor with one SNO monolayer exhibited artificial synaptic ***,the NKN memristor deposited on two SNO monolayers exhibited self-rectifying bipolar switching properties,with the two SNO monolayers acting as tunneling barriers in the *** conduction mechanism of the NKN memristor with two SNO monolayers in the highresistance state is attributed to Schottky emission,direct tunneling,and Fowler–Nordheim(FN)*** current conduction in this memristor in the low-resistance state was governed by direct tunneling and FN ***,the NKN memristor with two SNO monolayers exhibited large ON/OFF and rectification ratios and artificial synaptic ***,an NKN memristor with two SNO monolayers can be used for fabricating artificial synaptic devices with a cross-point array structure.

关键词： Bipolar switching properties Self-rectifying bipolar switching properties Artificial synaptic properties Crystalline NKN thin film Sr_(2)Nb_(3)O_(10)nanosheet seed layer

Influence of undissolved second-phase particles on dynamic recrystallization behavior of Mg–7Sn–1Al–1Zn alloy during low-and high-temperature extrusions

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journal of Materials Science & Technology 2021年第12期71卷 87-97页

作者： hyun ji Kim Sang-Cheol jin jae-Gil jung Sung Hyuk Park School of Materials Science and Engineering Kyungpook National UniversityDaegu41566Republic of Korea Implementation Research Division Korea Institute of Materials ScienceChangwon51508Republic of Korea

This study investigates the effects of fine and coarse undissolved particles in a billet of the Mg–7 Sn–1 Al–1 Zn(TAZ711)alloy on the dynamic recrystallization(DRX)behavior during hot extrusion at low and high temperatures and the resultant microstructure and mechanical properties of the *** this end,partially homogenized(PH)and fully homogenized(FH)billets are extruded at temperatures of250 and 450°*** PH billet contains fine and coarse undissolved Mg_(2) Sn particles in the interdendritic region and along the grain boundaries,*** fine particles(ynamically recrystallized(DRXed)grains of the extruded *** addition,the inhomogeneous distribution of fine particles in the PH billet leads to the formation of a bimodal DRXed grain structure with excessively grown grains in particle-scarce *** contrast,in the FH billet,numerous nanosized Mg_(2) Sn precipitates are formed throughout the material during extrusion at 250°C,which,in turn,leads to the formation of small,uniform DRXed grains by the grain-boundary pinning effect of the *** the PH billet is extruded at the high temperature of 450°C,the retardation effect of the fine particles on DRX is weakened by their dissolution in theα-Mg matrix and the increased extent of thermally activated grain-boundary *** contrast,the coarse Mg_(2) Sn particles in the billet promote DRX during extrusion through the particle-stimulated nucleation phenomenon,which results in an increase in the area fraction of DRXed *** both low and high extrusion temperatures,the extruded material fabricated using the PH billet,which contains both fine and coarse undissolved particles,has a lower tensile strength than that fabricated using the FH billet,which is virtually devoid of second-phase *** lower strength of the former is attributed mai

关键词： Mg–Sn alloy Second-phase particle Extrusion Homogenization Dynamic recrystallization

Diabetes mellitus type 2 drives metabolic reprogramming to promote pancreatic cancer growth

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Gastroenterology Report 2020年第4期8卷 261-276,I0001页

作者： Guermarie Velazquez-Torres Enrique Fuentes-Mattei hyun Ho Choi Sai-Ching j.yeung Xiangqi Meng Mong-Hong Lee Department of Molecular and Cellular Oncology Division of Basic Science ResearchThe University of Texas MD Anderson Cancer CenterHoustonTXUSA Guangdong Provincial Key laboratory of Colorectal and Pelvic Floor Disease Sun Yat-sen UniversityGuangzhouP.R.China Guangdong Research Institute of Gastroenterology The Sixth Affiliated Hospital of Sun Yat-sen UniversityGuangzhouP.R.China Department of Emergency Medicine Division of Internal Medicine The University of Texas MD Anderson Cancer CenterHoustonTXUSA

Background:Diabetes mellitus type 2(DM2)is a modifiable risk factor associated with pancreatic carcinogenesis and tumor progression on the basis of epidemiology studies,but the biological mechanisms are not completely *** purpose of this study is to demonstrate direct evidence for the mechanisms mediating these epidemiologic *** hypothesis is that DM2 accelerates pancreatic cancer growth and that metformin treatment has a beneficial ***:To determine the effect of glucose and insulin in pancreatic cancer proliferation,we used conditioned media to mimic DM2 ***,we studied the effect of anti-diabetic drugs,particularly metformin and rosiglitazone on pancreatic cancer *** established orthotopic/syngeneic(Leprdb/db)mouse cancer models to evaluate the effect of diabetes on pancreatic tumor growth and ***:Our results showed that diabetes promotes pancreatic tumor ***,enhanced tumor growth and aggressiveness(***-mesenchymal transition)can be explained by functional transcriptomic and metabolomic changes in the mice with diabetes,namely via activation of the AKT/mTOR *** treatment suppressed the diabetes-induced AKT/mTOR pathway activation and tumor *** metabolic profile determined by mass spectrum showed important changes of metabolites in the pancreatic cancer derived from diabetic mice treated with ***:Diabetes mellitus type 2 has critical effects that promote pancreatic cancer progression via transcriptomic and metabolomic *** animal models provide strong evidence for the causal relationship between diabetes and accelerated pancreatic *** study sheds a new insight into the effects of metformin and its potential as part of therapeutic interventions for pancreatic cancer in diabetic patients.

关键词： pancreatic cancer type 2 diabetes mellitus cancer metabolism

Development and first evaluation of an attractant impregnated adhesive tape against blood-sucking flies

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Insect Science 2022年第2期29卷 603-612页

作者： junwei j.Zhu Gwang-hyun Roh yosuke Asamoto Kujtim Bizati jen-Chieh Liu Alexander Lehmann Kyle Harrison David BTaylor Hironao Otake Agroecosystem Management Research Unit US Department of AgricultureAgricultural Research ServiceLincolnNebraskaUSA US Pacific Basin Agricultural Research Center US Department of AgricultureAgricultural Research ServiceHiloHawaiiUSA Oak Ridge Institute for Science and Education Oak RidgeTennesseeUSA Nitto Inc. TeaneckNew JerseyUSA Department of Entomology University of NebraskaLincolnNebraskaUSA

Stable flies are one of the most important arthropod pests of livestock that reduce cattle weight gain and milk production leading to annual economic losses in excess of$2 billion to the US cattle *** host-seeking behavior is primarily mediated by associated odors from stable fly larval development environments and host *** present paper reports the development and evaluation of attractant-impregnated adhesive tapes to reduce stable fly attacks on *** bioassays showed that only m-cresol impregnated adhesive tapes caught significantly more stable flies(16±1)than the control tape without attractant added(7±1),with a 77%fly recapture ***-impregnated adhesive tapes deployed in cattle feedlots showed significant impacts in reducing fly population,with a total of one million stable flies captured over a period of three weeks(mean catches from 57596 to 102088 stable flies per trap per week).It further relieved cattle stress with a significant reduction of biting fly avoidance behavior,(6±0.4 cows observed with tail wagging in control vs.3±0.4 from the trap-deployed).The efficacy of the developed tapes lasted up to 1-week longevity,although 70%of m-cresol was released starting from the second *** m-cresol impregnated adhesive tape provided an 80%reduction in cattle stress due to stable fly *** is the first report of a technology developed by integrating an attractant compound into an adhesive material on a plastic film with demonstrated effectiveness in trapping biting flies that attack livestock animals.

关键词： cattle stress reduction mass trapping m-cresol-impregnated adhesive tapes Stomoxys calcitrans

Recent progress in two-dimensional metallenes and their potential application as electrocatalyst

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journal of Energy Chemistry 2024年第7期94卷 577-598页

作者： Umer Shahzad Mohsin Saeed Muhammad Fazle Rabbee Hadi M.Marwani jehan y.Al-Humaidi Muhammad Altaf Raed H.Althomali Kwang-hyun Baek Md.Rabiul Awual Mohammed M.Rahman Department of Chemistry Faculty of ScienceKing Abdulaziz UniversityJeddah 21589Saudi Arabia Department of Biotechnology Yeungnam UniversityGyeongsanSouth Korea Center of Excellence for Advanced Materials Research(CEAMR) King Abdulaziz UniversityJeddah 21589Saudi Arabia Department of Chemistry College of SciencePrincess Nourah Bint Abdulrahman UniversityP.O.BOX 84428Riyadh 11671Saudi Arabia Department of Chemistry Center of Excellence for Innovation in Chemistry(PERCH-CIC)Center of Excellence in Materials Science and TechnologyFaculty of ScienceChiang Mai UniversityChiang Mai 50200Thailand Department of Chemistry College of Art and SciencePrince Sattam Bin Abdulaziz UniversityWadi Al-Dawasir 11991Saudi Arabia Western Australian School of Mines:Minerals Energy and Chemical EngineeringCurtin UniversityGPO Box U 1987PerthWA 6845Australia

In this article,we looked at metallenes,a novel class of two-dimensional(2D)metals that are attracting interest in the energy and catalysis *** is one area where their exceptional physicochemical and electrical characteristics might be *** are unique because they include several metal atoms that are not in a coordinated *** makes them more active and improves their atomic uti-lization,which in turn increases their catalytic *** article delves into the potential of two-dimensional metals as electrocatalysts for carbon dioxide reduction,fuel oxidation,oxygen evolution,and oxygen reduction reactions in the context of sustainable energy *** to the exception-ally high surface-to-volume ratio,large surface area as well as their optimized atomic use efficiency,2D materials defined by atomic layers are crucial for surface-related sustainable energy *** to its exceptional properties,such as high conductivity and the ability to enhance the exposure of active metal sites,2D metallenes have recently attracted a lot of interest for use in catalysis,electronics,and energy-related *** their highly mobility,adjustable surface states,and electrical struc-tures that can be fine-tuned,2D metallenes are promising nanostructure materials for use in energy con-version with the sustainable applications.

关键词： Metallenes Electrocatalysts Electrochemical processes Atomically thin structure

Unilateral versus bilateral y-type stent-in-stent metal stent insertions in inoperable malignant hilar biliary strictures:A multicenter retrospective study

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Hepatobiliary & Pancreatic Diseases International 2021年第6期20卷 561-567页

作者： Ik hyun jo Chang-Nyol Paik Dae Bum Kim jaesin Lee jong yul Lee jae Hyuck Chang Kyu-hyun Paik Won-Suk Park Department of Internal Medicine College of MedicineSt.Vincent’s HospitalThe Catholic University of KoreaSeoulKorea Department of Internal Medicine College of MedicineIncheon St.Mary’s HospitalThe Catholic University of KoreaSeoulKorea Department of Internal Medicine College of MedicineBucheon St.Mary’s HospitalThe Catholic University of KoreaSeoulKorea Department of Internal Medicine College of MedicineDaejeon St.Mary’s HospitalThe Catholic University of KoreaSeoulKorea

Background:To date,there is controversy regarding unilateral versus bilateral stent placement in patients with malignant hilar biliary strictures(MHBSs).The aim of this study was to compare the clinical outcomes and complications of unilateral and bilateral(stent-in-stent method)stent placements for these ***:We conducted a multicenter retrospective analysis of patients with inoperable MHBS who underwent endoscopic self-expandable metal stent(SEMS)placement from january 2009 to December *** groups classified according to the stent procedure method were compared for demographic,procedural,and postprocedure *** analysis for patency loss and overall survival was also ***:A total of 236 subjects were included.A superior technical success rate was found in the unilateral stent group(98.8%vs.82.5%,Py loss,and the bilateral group had better overall survival(Pymph node compression were associated with a higher risk of death(HR=9.803,P=0.003).In contrast,bilateral SEMS insertion showed reduced postprocedural mortality(HR=0.316,P=0.001).Conclusions:y-type stent-in-stent bilateral SEMSs are technically difficult but demonstrated more favorable overall survival for palliative bile drainage of inoperable MHBS patients compared to unilateral insertions.

关键词： Cholestasis Extrahepatic neoplasm Cholangiopancreatography Endoscopy Self-expandable metal stents