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Journal of Rare Earths 2016年第1期34卷 45-54页

作者： Younes HANIFEHPOUR Nazanin HAMNABARD Bamin KHOMAMI Sang Woo JOO bong-ki min Jae Hak JUNG School of Mechanical Engineering Yeungnam University Department of Chemical and Biomolecular Engineering University of Tennessee Center for Research Facilities Yeungnam University School of Chemical Engineering Yeungnam University

Novel high-efficiency visible-light-sensitive Nd-doped CdTe nanoparticles were prepared with various doping concentra- tions of neodymium ion by a facile hydrothermal method. The reaction products were analyzed via X-ray diffraction （XRD）, scanning electron microscopy （SEM）, transmission electron microscopy （TEM）, photoelectron spectroscopy （XPS）, and UV-Vis diffuse re- flectance spectroscopy techniques. Red shift was seen in the absorption band edge peak in the UV-Vis absorbance specmun with in- creasing Nd content. The XRD and XPS results confirmed that Nd ions successfully replaced Cd atoms and were incorporated into the crystal lattice of CdTe. SEM and TEM images indicated spherical structure and high crystallinity. Even at a very low Nd/CdTe molar ratio of 2 mol.%, Nd doping could greatly enhance the photocatalytic activity of CdTe. The photocatalytic activity of Nd-doped CdTe nanoparticles was evaluated by monitoring the decolorization of RRed 43 in aqueous solution under visible-light irradiation. The color removal efficiency of Nd0.08Cd0.9eYe and pure CdTe were 83.14% and 14.32% after 100 min of treatment, respectively. Among different amounts of the doping agent, 8 tool.% Nd indicated the highest decolorization. The presence of radical scavengers such as CF, CO3-, SO4〉, and huthanol was found to reduce the decolorization efficiency.

关键词： neodymium cadmium telluride hydrothermal photocatalyst rare earths

A simple,sensitive and non-destructive technique for characterizing bovine dental enamel erosion:attenuated total reflection Fourier transform infrared spectroscopy

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International Journal of Oral Science 2016年第1期8卷 54-60页

作者： In-Hye kim Jun Sik Son bong ki min Young Kyoung kim Kyo-Han kim Tae-Yub Kwon Department of Dental Science Graduate SchoolKyungpook National UniversityDaeguKorea Korea Textile Development Institute DaeguKorea Center for Research Facilities Yeungnam UniversityGyeongsanKorea Department of Conservative Dentistry School of DentistryKyungpook National UniversityDaeguKorea Department of Dental Biomaterials School of DentistryKyungpook National UniversityDaeguKorea

Although many techniques are available to assess enamel erosion in vitro, a simple, non-destructive method with sufficient sensitivity for quantifying dental erosion is required. This study characterized the bovine dental enamel erosion induced by various acidic beverages in vitro using attenuated total reflection Fourier transform infrared （ATR-FTIR） spectroscopy. Deionized water （control） and 10 acidic beverages were selected to study erosion, and the pH and neutralizable acidity were measured. Bovine anterior teeth （110） were polished with up to 1 200-grit silicon carbide paper to produce flat enamel surfaces, which were then immersed in 20 mL of the beverages for 30 min at 37 ℃. The degree of erosion was evaluated using ATR-FTIR spectroscopy and Vickers＇ microhardness measurements. The spectra obtained were interpreted in two ways that focused on the ~1, ~3 phosphate contour： the ratio of the height amplitude of ~3 P04 to that of/11 P04 （Method 1） and the shift of the v3 P04 peak to a higher wavenumber （Method 2）. The percentage changes in microhardness after the erosion treatments were primarily affected by the pH of the immersion media. Regression analyses revealed highly significant correlations between the surface hardness change and the degree of erosion, as detected by ATR-FTIR spectroscopy （P〈0.001）. Method 1 was the most sensitive to these changes, followed by surface hardness change measurements and Method 2. This study suggests that ATR- FTIR spectroscopy is potentially advantageous over the microhardness test as a simple, non-destructive, sensitive technique for the quantification of enamel erosion.

关键词： acidic beverage enamel erosion Fourier transform infrared spectroscopy microhardness sensitivity

Chemical and mechanical properties of stainless, environment-friendly, and nonflammable Mg alloys (SEN alloys): A review

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Journal of Magnesium and Alloys 2024年第3期12卷 841-872页

作者： Jong Un Lee Hyun Ji kim Sang-Cheol Jin Ye Jin kim Young min kim bong Sun You Jun Ho Bae Sung Hyuk Park Advanced Metals Division Korea Institute of Materials ScienceChangwon 51508Republic of Korea Department of Materials Science and Metallurgical Engineering Kyungpook National UniversityDaegu 41566Republic of Korea Missile Research Institute Agency for Defense DevelopmentDaejeon 34060Republic of Korea

This review article provides overall understanding of stainless,environment-friendly,and nonflammable Mg alloys(SEN alloys)recently developed at the Korea Institute of Materials *** alloys are produced by adding small amounts of Ca and Y(eachminor amounts of Ca and Y renders excellent mechanical properties due to improved strengthening *** enhanced properties are attributed to more pronounced dynamic recrystallization and grain refining behaviors caused by the second-phase particles during extrusion.(4)Despite the presence of various types of second-phase particles,the fatigue properties of SEN9 alloys are similar to those of commercial AZ91 alloys.(5)Simultaneous introduction of Ca and Y suppresses the formation of Mg17Al12 discontinuous precipitates during aging,leading to the enhanced elongation of aged SEN alloys.(6)Adding mischmetal into the SEN9 alloy leads to a six-fold enhancement in ***,the studies conducted on SEN alloys demonstrate their excellent ignition and corrosion resistances and mechanical properties,which broaden the industrial applications of Mg alloys by addressing their inherent weaknesses.

关键词： SEN magnesium alloy Corrosion resistance Ignition resistance Mechanical properties Extrudability.

Enhancement of porcine in vitro embryonic development through luteolin‑mediated activation of the Nrf2/Keap1 signaling pathway

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Journal of Animal Science and Biotechnology 2024年第2期15卷 600-613页

作者： Se-Been Jeon Pil-Soo Jeong min Ju kim Hyo-Gu Kang bong-Seok Song Sun-Uk kim Seong-Keun Cho Bo-Woong Sim Futuristic Animal Resource&Research Center(FARRC) Korea Research Institute of Bioscience and Biotechnology(KRIBB)Cheongju 28116Republic of Korea Department of Animal Science College of Natural Resources&Life SciencePusan National UniversityMiryang 50463Republic of Korea Department of Animal Science and Biotechnology College of Agriculture and Life ScienceChungnam National UniversityDaejeon 34134Republic of Korea Department of Functional Genomics University of Science and TechnologyDaejeon 34113Republic of Korea Department of Animal Science Life and Industry Convergence Research Institute(RICRI)College of Natural Resources&Life SciencePusan National UniversityMiryang 50463Republic of Korea

Background Oxidative stress,caused by an imbalance in the production and elimination of intracellular reactive oxygen species(ROS),has been recognized for its detrimental effects on mammalian embryonic ***(Lut)has been documented for its protective effects against oxidative stress in various ***,its specific role in embryonic development remains *** study aims to investigate the influence of Lut on porcine embryonic development and to elucidate the underlying *** After undergoing parthenogenetic activation(PA)or in vitro fertilization,embryos supplemented with 0.5μmol/L Lut displayed a significant enhancement in cleavage and blastocyst formation rates,with an increase in total cell numbers and a decrease in the apoptosis rate compared to the *** on D2 and D6 revealed that embryos with Lut supplementation had lower ROS levels and higher glutathione levels compared to the ***,Lut supplementation significantly augmented mitochondrial content and membrane ***,activation of the Nrf2/Keap1 signaling pathway was observed in embryos supplemented with Lut,leading to the upregulation of antioxidant-related gene transcription *** further validate the relationship between the Nrf2/Keap1 signaling pathway and effects of Lut in porcine embryonic development,we cultured PA embryos in a medium supplemented with brusatol,with or without the inclusion of *** positive effects of Lut on developmental competence were negated by brusatol *** Our findings indicate that Lut-mediated activation of the Nrf2/Keap1 signaling pathway contributes to the enhanced production of porcine embryos with high developmental competence,and offers insight into the mechanisms regulating early embryonic development.

关键词： Luteolin Mitochondrial function Nrf2/Keap1 signaling pathway Oxidative stress Porcine embryo development

Discharge Characteristics of Large-Area High-Power RF Ion Source for Positive and Negative Neutral Beam Injectors

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Plasma Science and Technology 2016年第12期18卷 1220-1224页

作者： Doo-Hee CHANG Seung Ho JEONG min PARK Tae-Seong kiM bong-ki JUNG Kwang Won LEE Sang Ryul IN Division of Nuclear Fusion Engineering & Technology Development Korea Atomic Energy Research Institute

A large-area high-power radio-frequency（RF） driven ion source was developed for positive and negative neutral beam injectors at the Korea Atomic Energy Research Institute（KAERI）. The RF ion source consists of a driver region, including a helical antenna and a discharge chamber, and an expansion region. RF power can be transferred at up to 10 kW with a fixed frequency of 2 MHz through an optimized RF matching system. An actively water-cooled Faraday shield is located inside the driver region of the ion source for the stable and steady-state operations of high-power RF discharge. Plasma ignition of the ion source is initiated by the injection of argongas without a starter-filament heating, and the argon-gas is then slowly exchanged by the injection of hydrogen-gas to produce pure hydrogen plasmas. The uniformities of the plasma parameter,such as a plasma density and an electron temperature, are measured at the lowest area of the driver region using two RF-compensated electrostatic probes along the direction of the shortand long-dimensions of the driver region. The plasma parameters will be compared with those obtained at the lowest area of the expansion bucket to analyze the plasma expansion properties from the driver region to the expansion region.

关键词： neutral beam injector RF ion source plasma ignition power loading plasma parameters

GRID GENERATION IN SPACE AND CALCULATION FOR 3-D TURBULENT FLOW

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Journal of Hydrodynamics 1991年第1期3卷 66-71页

作者： Zheng, bong-min Chao, ming-deng Wuhan Univ of Hydraulic and Electric Engineering Wuhan China

In this paper we studied three dimensional flow with inlet and outlet. We used nonorthogonal curvilinear body-fitted coordinates for the governing equations and grid generation, and gave the physical components for velocity flow field. We used two scale k-Ε-E model for large and small vortices respectively. The computation gives U, V, W, P, T, K, Ε, seven variables. The numerical results of the velocity and temperature distribution agree with the practical data. This method can calculate the vortex, circulation and secondary flow and may be widely used in river flow and in environmental hydraulic problems.

关键词： Computers Applications Hydrodynamics Mathematical Models Mathematical Techniques Finite Element Method Rivers

Hot deformation behavior and processing maps of Mg-Zn-Cu-Zr magnesium alloy

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Transactions of Nonferrous Metals Society of China 2013年第3期23卷 756-764页

作者：余晖于化顺 Young-min kiM bong-sun YOU 闵光辉山东大学材料科学与工程学院材料液固结构演变与加工教育部重点实验室 Light Metals Group Korea Institute of Mate rials ScienceChangwon 642831Korea

The deformation behaviors of a new quaternary Mg-6Zn-1.5Cu-0.5Zr alloy at temperatures of 523-673 K and strain rates of 0.001-1 s-1 were studied by compressive tests using a Gleeble 3800 *** results show that the flow stress increases as the deformation temperature decreases or as the strain rate increases.A strain-dependent constitutive equation and a feed-forward back-propagation artificial neural network were used to predict flow stress,which showed good agreement with experimental *** processing map suggests that the domains of 643-673 K and 0.001-0.01 s-1 are corresponded to optimum conditions for hot working of the T4-treated Mg-6Zn-1.5Cu-0.5Zr alloy.

关键词： Mg alloy Cu addition flow stress deformation behavior constitutive equation artificial neural network processing map

High tibial osteotomy with human umbilical cord blood-derived mesenchymal stem cells implantation for knee cartilage regeneration

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World Journal of Stem Cells 2020年第6期12卷 514-526页

作者： Jun-Seob Song ki-Taek Hong Chae-Gwan Kong Na-min kim Jae-Yub Jung Han-Soo Park Young Ju kim ki bong Chang Seok Jung kim Department of Orthopedic Surgery Gangnam JS HospitalSeoul 06053South Korea Department of Orthopedic Surgery College of MedicineThe Catholic University of KoreaUijeongbu-si 11765South Korea Department of Nursing Education&Administration Uijeongbu St.Mary’s HospitalThe Catholic University of KoreaUijeongbu-si 11765South Korea

BACKGROUND High tibial osteotomy(HTO)is a well-established method for the treatment of medial compartment osteoarthritis of the knee with varus ***,HTO alone cannot adequately repair the arthritic joint,necessitating cartilage regeneration *** regeneration procedures with concomitant HTO are used to improve the clinical outcome in patients with varus *** To evaluate cartilage regeneration after implantation of allogenic human umbilical cord blood-derived mesenchymal stem cells(hUCB-MSCs)with concomitant *** Data for patients who underwent implantation of hUCB-MSCs with concomitant HTO were *** patients included in this study were over 40 years old,had a varus deformity of more than 5°,and a full-thickness International Cartilage Repair Society(ICRS)grade IV articular cartilage lesion of more than 4 cm2 in the medial compartment of the *** patients underwent second-look arthroscopy during hardware *** regeneration was evaluated macroscopically using the ICRS grading system in second-look *** also assessed the effects of patient characteristics,such as trochlear lesions,age,and lesion size,using patient medical *** A total of 125 patients were included in the study,with an average age of 58.3±6.8 years(range:43-74 years old);95(76%)were female and 30(24%)were *** average hip-knee-ankle(HKA)angle for measuring varus deformity was 7.6°±2.4°(range:5.0-14.2°).In second-look arthroscopy,the status of medial femoral condyle(MFC)cartilage was as follows:73(58.4%)patients with ICRS grade I,37(29.6%)with ICRS grade II,and 15(12%)with ICRS grade *** patients were staged with ICRS grade ***,the scores[except International Knee Documentation Committee(IKDC)at 1 year]of the ICRS grade I group improved more significantly than those of the ICRS grade II and III *** Implantation of hUCB-MSCs with concomitant HTO is an effective treatment for patients wit

关键词： Allogeneic Human umbilical cord blood-derived mesenchymal stem cells Cartilage regeneration High tibial osteotomy Osteoarthritic knees Arthroscopy

Optimization of thermoelectric properties of n-type Bi_2(Te,Se)_3 with optimizing ball milling time

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Rare Metals 2018年第4期37卷 351-359页

作者： Ji-Hee Son min-Wook Oh bong-Seo kim Su-Dong Park Thermoelectric Conversion Research Center Korea Electrotechnology Research Institute Department of Materials Science and Engineering Hanbat National University

The thermoelectric properties at elevated temperature were investigated for n-type Bi2（Te,Se）3 which is obtained from ball milling processed powder with various milling times. Electrical properties such as electrical resistivity and Seebeck coefficient are clearly dependent on milling time, in which the carrier concentration is attributed to the change of the electrical properties. The concentrations of the defects are also varied with the ball milling time, which is the origin of the carrier concentration variation. Even though finer grain sizes are obtained after the long ball milling time, the temperature dependence of the thermal conductivity is not solely understood with the grain size, whereas the electrical contribution to the thermal conductivity should be also considered. The highest figure of merit value of ZT = 0.83 is achieved at 373 K for the optimized samples, in which ball milling time is 10 h. The obtained ZT value is 48% improvement over that of the 0.5-h sample at 373 K.

关键词： Thermoelectric properties Ball milling Bi2Te3 Seebeck coefficient Grain size Thermalconductivity

Management of obstructive colon cancer:Current status,obstacles,and future directions

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World Journal of Gastrointestinal Oncology 2021年第12期13卷 1850-1862页

作者： Ri-Na Yoo Hyeon-min Cho bong-Hyeon Kye Division of Colorectal Surgery Department of SurgerySt.Vincent’s HospitalThe Catholic University of KoreaSuwon 442-723South Korea

Approximately 10%–18%of patients with colon cancer present with obstruction at the initial *** active screening efforts,the incidence of obstructive colon cancer remains ***,emergency surgery has been indicated to treat patients with obstructive colon ***,compared to patients undergoing elective surgery,the morbidity and mortality rates of patients requiring emergency surgery for obstructive colon cancer are *** the advancement of colonoscopic techniques and equipment,a self-expandable metal stent(SEMS)was introduced to relieve obstructive symptoms,allowing the patient’s general condition to be restored and for them undergo elective *** the use of SEMS placement is growing,controversies about its application in potentially curable diseases have been *** this review,the short-and longterm outcomes of different treatment strategies,particularly emergency surgery vs SEMS placement followed by elective surgery in resectable,locally advanced obstructive colon cancer,are described based on the location of the obstructive cancer *** regarding each treatment strategy are *** overcome current obstacles,a potential diagnostic method using circulating tumor DNA and further research directions incorporating neoadjuvant chemotherapy are introduced.

关键词： Colonic neoplasms Self-expandable metallic stents Intestinal obstruction Survival rate Morbidity Mortality