Magnetism in Ni-W textured substrates for coated conductors

Song K. J.,Park Y. M.,Yang J. S.,Kim S. W.,Ko R. K.,Kim H. S.,Ha H. S,Oh S. S.,Park C.,Joo J. H.,Kim C. J. The Korea Institute of Applied Superconductivity a 2005 한국초전도저온공학회논문지 Vol.7 No.2

The magnetic properties of a series of both annealed (biaxially textured) and as-rolled (non-textured) Ni-xW alloy tapes with compositions x = 0,1,3, and 5 at.$\%$, were studied. Characterization methods included XRD analyses to investigate the biaxial cube texturing of the annealed Ni-W alloy tapes and studies of the magnetization M for both annealed and as-rolled Ni-W alloy tapes. Both the isothermal mass magnetizations M(H) of a series of samples at different fixed temperatures and M(T) in fixed field, employing a PPMS-9 (Quantum Design), were measured. The Ni-W alloys have shown much reduced ferromagnetism as W-content x increases. Both the saturation magnetization Msat and Curie temperature Tc decrease linearly with W-content x, and both Msat and Tc go to zero at critical concentration of Xc - 9.50 at. $\%$ W.

Effects of the addition of ZnO and Y₂O₃ on the electrochemical characteristics of a Ni(OH)₂ electrode in nickel-metal hydride secondary batteries

Jung, K.W.,Yang, D.C.,Park, C.N.,Park, C.J.,Choi, J. Pergamon Press ; Elsevier Science Ltd 2010 International journal of hydrogen energy Vol.35 No.23

This study examined the effects of the addition of ZnO and Y<SUB>2</SUB>O<SUB>3</SUB> on the electrochemical characteristics of a Ni(OH)<SUB>2</SUB> electrode in nickel-metal hydride (Ni-MH) secondary batteries. The discharge capacity of the electrode was less affected by the addition of ZnO and Y<SUB>2</SUB>O<SUB>3</SUB> at a 0.2 C-rate and 25<SUP>o</SUP>C. However, the addition of Y<SUB>2</SUB>O<SUB>3</SUB> deteriorated the discharge capacity and the cycle life of the electrode by increasing the charge transfer resistance of the electrode at an increased C-rate of 1 C and 25<SUP>o</SUP>C. Under severer conditions at 1 C-rate and 60<SUP>o</SUP>C, the electrode materials were separated from the current collector and, accordingly, the discharge capacity was abruptly degraded with cycling for the electrodes comprising only 4wt% ZnO or 4wt% Y<SUB>2</SUB>O<SUB>3</SUB>. In contrast, the electrodes containing both 2wt% ZnO and 2wt% Y<SUB>2</SUB>O<SUB>3</SUB> exhibited stable discharge capacity with cycling and excellent cycle life due to the high overvoltage for oxygen evolution. The present results indicate that the addition of ZnO and Y<SUB>2</SUB>O<SUB>3</SUB> with an optimum composition suppresses oxygen evolution in the interfaces between active materials and the current collector and improves the cycle life of the electrode.

Development of additive [¹¹C]CO₂ target system in the KOTRON-13 cyclotron and its application for [¹¹C]radiopharmaceutical production

Moon, B.S.,Lee, H.J.,Lee, W.K.,Hur, M.G.,Yang, S.D.,Lee, B.C.,Kim, S.E. North-Holland Physics Pub 2015 Nuclear instruments & methods in physics research. Vol.356 No.-

The KOTRON-13 cyclotron, which was developed in South Korea for the production of medical radioisotopes, has the structural limitation of only one beam-output port, restricting the production of the carbon-11 isotope. In the present study, we investigate the design of a switchable target system and develop an effective carbon-11 target in the KOTRON-13 cyclotron, for combination with the fluorine-18 target. The target system was designed by introducing a sliding-type element between the fluorine-18 and carbon-11 targets, a tailor-made C-11 target and its cooling system. For the efficient production of [<SUP>11</SUP>C]CO<SUB>2</SUB>, the desirable target shape and internal volume were determined by a Stopping and Range of Ions in Matter (SRIM) simulation program, and the target grid was modified to resist the cavity pressure during beam irradiation. We evaluated the [<SUP>11</SUP>C]CO<SUB>2</SUB> production while varying the material and thickness of the target foil, oxygen content of the nitrogen gas, and target loading pressure. Using sliding-type equipment including an additional gate valve and a high vacuum in a beam line, the bi-directional conversion between the fluorine-18 and carbon-11 targets was efficient regarding the accurate beam irradiation on both targets. The optimal [<SUP>11</SUP>C]CO<SUB>2</SUB> production for 30min irradiation at 60μA (86.6+/-1.7GBq in the target at EOB) was observed at a thickness of 19μm with HAVAR® material as a target foil and a target loading pressure of 24bar with nitrogen plus 300ppb of oxygen gas. Additionally, the coolant cavity system in the target grid and target chamber is useful to remove the heat transferred to the target body by the internal convection of water and thereby ensure the stability of the [<SUP>11</SUP>C]CO<SUB>2</SUB> production under a high beam current. In the application of C-11 labeled radiopharmaceuticals such as [<SUP>11</SUP>C]PIB, [<SUP>11</SUP>C]DASB, [<SUP>11</SUP>C]PBR28, [<SUP>11</SUP>C]Methionine and [<SUP>11</SUP>C]Clozapine, the radiochemical yields were shown to be 25-38% (decay corrected) with over 166GBq/μmol of specific activity. Consequently, the additive carbon-11 target system was successfully developed in only one output port of the KOTRON-13 cyclotron and exhibited the stable production of C-11 labeled radiopharmaceuticals.

Metal(loid) immobilization in soils with biochars pyrolyzed in N₂ and CO₂ environments

Igalavithana, Avanthi Deshani,Yang, Xiao,Zahra, Hilda Rizkia,Tack, Filip M.G.,Tsang, Daniel C.W.,Kwon, Eilhann E.,Ok, Yong Sik Elsevier 2018 Science of the Total Environment Vol.630 No.-

<P><B>Abstract</B></P> <P>Previous studies indicated that using CO<SUB>2</SUB> as a reaction agent in the pyrolysis of biomass led to an enhanced generation of syngas <I>via</I> direct reaction between volatile organic carbons (VOCs) evolved from the thermal degradation of biomass and CO<SUB>2</SUB>. In addition, the physico-chemical properties of biochar in CO<SUB>2</SUB> were modified. In this current study, biochars generated from red pepper stalks in N<SUB>2</SUB> and CO<SUB>2</SUB> (RPS-N and RPS-C, respectively) were tested for their effects on the immobilization of Pb, Cd, Zn, and As in contaminated soils. Soils were incubated for one month with 2.5% of RPS, and two biochars (<I>i.e.</I>, RPS-N and RPS-C) at 25°C. After the incubation period soils were analyzed to determine the amendment effects on the behavior of metal(loid)s. The potential availability and mobility kinetics of metal(loid)s were assessed by single extraction of ammonium acetate and consecutive extraction of calcium chloride, respectively. Sequential extraction was used to further examine potential changes in geochemical fractions of metal(loid)s. The increased soil pH induced by application of the biochars reduced the potentially available Pb, Cd, and Zn, while RPS-C significantly reduced Pb due to the high surface area and aromaticity of RPS-C. However, RPS-C mobilized potentially available As compared to RPS-N due to the increased soil pH. Biochars reduced the mobility kinetics of Pb, Cd, and Zn, and RPS-N effectuated the greatest reduction of As mobility. The RPS-C increased the Fe and Mn oxides, hydroxide, and organically bound Pb, while both biochars and RPS-N increased residual Cd and Zn, and organically bound As, respectively. When considering the two biochars, RPS-C was highly effective for immobilization of Pb in soils, but it had no effect on Cd and Zn and a negative effect on As. In addition, RPS-C significantly increased the total exchangeable cations in soils.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Biochars markedly reduced Cd, Pb and Zn mobility in soils. </LI> <LI> Biochar pyrolyzed in CO<SUB>2</SUB> most effectively immobilized Pb. </LI> <LI> Biochar pyrolyzed in CO<SUB>2</SUB> increases As mobility more. </LI> <LI> More siloxane groups present in biochar pyrolysed in CO<SUB>2</SUB>. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

CTRP1 protects against diet-induced hyperglycemia by enhancing glycolysis and fatty acid oxidation

Han, S.,Park, J.S.,Lee, S.,Jeong, A.L.,Oh, K.S.,Ka, H.I.,Choi, H.J.,Son, W.C.,Lee, W.Y.,Oh, S.J.,Lim, J.S.,Lee, M.S.,Yang, Y. Butterworths ; Elsevier Science Ltd 2016 The Journal of nutritional biochemistry Vol.27 No.-

<P>Complement-C1q/tumor necrosis factor-alpha related protein 1 (CTRP1) is a 35-kDa glycoprotein that is secreted from various tissues. Although CTRP1 is highly increased in patients with type II diabetes and obesity, the metabolic roles of CTRP1 remain largely unknown. To unveil the physiological roles of CTRP1 in vivo, CTRP1 transgenic (TG) mice were challenged by a high-fat diet (HFD) and a high-sucrose drink (HS). Homeostatic model assessment-estimated insulin resistance values were decreased in HFD- or HS-fed CTRP1 TG mice compared with wild-type control mice. In this context, CTRP1 stimulated glucose uptake through the glucose transporter GLUT4 translocation to the plasma membrane and also increased glucose consumption by stimulating glycolysis. To analyze the roles of CTRP1 in lipid metabolism, acetyl-CoA carboxylase (ACC) and hormone-sensitive lipase levels were determined in CTRP1 TG mice, and the effect of CTRP1 on fatty acid oxidation was assessed in C2C12 myotubes. CTRP1 was found to inhibit ACC by phosphorylation and to stimulate fatty acid oxidation in C2C12 myotubes. Taken together, CTRP1 performs active catabolic roles in vivo. Therefore, CTRP1 seems to perform a defensive function against nutritional challenges. (C) 2015 Elsevier Inc. All rights reserved.</P>

Glycosylation of Lipoprotein Lipase in Human Subcutaneous Lipomas

(J . W . Park),(J . Y . Yang),(S . R . Rhee),(C . G . Cho),(B . H . Park),(H . W . Rho),(J . S . Kim),(H . R . Kim) 전북대학교 의과학연구소 1996 全北醫大論文集 Vol.20 No.2

동결속도와 평형시간이 소 미성숙 난자의 동결 융해후 생존율에 미치는 영향

양병철,양보석,성환후,임기순,최선호,장원경,진동일,임경순 한국가축번식학회 2001 Reproductive & developmental biology Vol.25 No.1

The present study was undertaken to investigate the effects of cooling rate and equilibration time on the survival, in vitro maturation and development to embryos of frozen-thawed bovine immature oocytes(Germinal Vesicle Stage). The cryoprotectants are used 10% ethylene glycol(EG) as permeating cryoprotectant and 0.05M sucrose(S) or trehalose(T) as low molecular weight nonpermeating cryoprotectants and 5% ficoll(F) or polyvinylpyrrolidone(PVP) as high molecular weight nonpermeating cryoprotectants. Four freezing solution were uysed in this experiment(EFT: 10% EG + 5% F + 0.05M T, EFS: 10% EG + 5% F + 0.05M S, EPT: 10% EG + 5% P + 0.05M T, EPS: 10% EG + 5% P + 0.05M S). The best equilibration time and freezing solution was 15 min in EPT(83% survival rate of frozen-thawed bovine immature oocytes). When frozen-thawed bovine oocytes were cultured following IVM and IVF, there was no significant difference in cleavage and development rates among the EFT, EFS, EPT and EPS solutions. When 9 blastocysts derived from frozen bovine oocytes were transferred to 6 recipients, two recipients were pregnant. And one was aborted at 45 days of pregnancy and the other had a stillbirth.

Au-Si 나노점을 촉매로 성장한 Si 나노선의 구조 및 광학적 특성 연구

이연환,곽동욱,양우철,Lee, Y.H.,Kwak, D.W.,Yang, W.C.,Cho, H.Y. 한국진공학회 2008 Applied Science and Convergence Technology Vol.17 No.1

나노크기의 Au-Si을 촉매로 급속열화학기상증착(rapid thermal chemical vapor deposition)법을 이용하여 Si(111) 기판에 성장한 Si 나노선의 구조적인 형태 변화와 광학적 특성을 연구하였다. 기상-액상-고상(vapor-liquid-solid) 성장법에 의한 Si 나노선 형성 과정에서 액상 입자인 Au-Si 나노점은 나노선 성장온도에서 촉매로 사용되었다. 이 액상 나노점이 형성된 Si 기판에 1.0Torr 압력과 $500-600^{\circ}C$ 기판 온도 하에서 $SiH_4$와 $H_2$의 혼합가스를 공급하여 Si 나노선을 형성하였다. Si 나노선 성장 후 형태를 전계방출 주사전자현미경(Field Emission Scanning Electron Microscope)으로 관찰한 결과, 대부분의 나노선이 균일한 크기로 기판 표면에 수직하게 <111> 방향으로 정렬된 것을 확인하였다. 형성된 나노선의 크기는 평균 직경이 ${\sim}60nm$이고 평균 길이가 ${\sim}5um$임을 확인하였다. 또한 고 분해능 투과전자현미경(High Resolution-Transmission Electron Microscope) 관찰을 통해 Si 나노선은 약 3nm의 비정질 산화층으로 둘러 싸여 있는 Si 단결정임이 분석되었다. 그리고 마이크로 라만 분광(Micro-Raman Scattering)법을 통한 광학적 특성 분석 결과, Si의 광학 포논(Optical Phonon) 신호 위치가 Si 나노선 구조의 영향으로 낮은 에너지 쪽으로 이동하며, Si 포논 신호의 폭이 비대칭적으로 증가함을 확인하였다. we have demonstrated structural evolution and optical properties of Si-nanowires (NWs) synthesized on Si (111) substrates with nanoscale Au-Si islands by rapid thermal chemical vapor deposition (RTCVD). The Au-Si nano-islands (10-50nm in diameter) were employed as a liquid-droplet catalysis to grow Si-NWs via vapor-liquid-solid mechanism. The Si-NWs were grown by a mixture gas of SiH4 and H2 at a pressure of 1.0 Torr and temperatures of $500{\sim}600^{\circ}C$. Scanning electron microscopy measurements showed that the Si-NWs are uniformly sized and vertically well-aligned along <111> direction on Si (111) surfaces. The resulting NWs are ${\sim}60nm$ in average diameter and ${\sim}5um$ in average length. High resolution transmission microscopy measurements indicated that the NWs are single crystals covered with amorphous SiOx layers of ${\sim}3nm$ thickness. In addition, the optical properties of the NWs were investigated by micro-Raman spectroscopy. The downshift and asymmetric broadening of the Si main optical phonon peak were observed in Raman spectra of Si-NWs, which indicates a minute stress effects on Raman spectra due to a slight lattice distortion led by lattice expansion of Si-NW structures.

저주파 자극기에 적용 가능한 UV-C LED 구비 모듈형 소독기 개발에 관한 연구

송종익(J. I. Song),서기호(G. H. Seo),이민우(M.W. Lee),서지원(J. W. Seo),김형태(H. T. Kim),양경선(K. S. Yang),고철웅(C. W. Ko) Korean Society for Precision Engineering 2019 한국정밀공학회 학술발표대회 논문집 Vol.2019 No.10월

나사못의 압출시험을 통한 경추 금속판 잠금 구조의 안정성 평가

전창수(C. S. Chon),김상윤(S. Y. Kim),강경민(K. M. Kang),신효철(H. C. Shin),김남권(N. K. Kim),양경선(K. S. Yang),정구희(G. H. Jung),고철웅(C. W. Ko) Korean Society for Precision Engineering 2019 한국정밀공학회 학술발표대회 논문집 Vol.2019 No.10월