Fe-Cu-M-(Si, B) (M = V, Nb, Mo, Ta, W) 합금의 연자기특성 (軟磁氣特性)

강일구,김희중,노태환,이명복,피우갑 대한금속재료학회(대한금속학회) 1990 대한금속·재료학회지 Vol.28 No.4

Dependence of the effective permeability on annealing and the annealing-induced structural change for amorphous Fe_(73.5)Cu₁M₃Si_(13.5)B_9(M=V, Nb, Mo, Ta or W)and Fe_(73.5)Cu₁Nb₃(Si_xB_(1-x))_(22.5)(x=0∼0.8) alloys were investigated. Crystalline Fe_(73.5)Cu₁M₃Si_(13.5)B_9(M=V, Nb, Mo, W)alloys with α-Fe phase which was obtained by annealing at above T_x showed higher effective permeability than with amorphous phase, and the increase in permeability upon crystallization was large in the order of V$lt;W$lt;Mo$lt;Nb. For amorphous Fe_(73.5)Cu₁Nb₃(Si_xB_(1-x))_(22.5) alloys in the composition range from x=0.5 to 0.8, soft magnetic property was improved by crystallization. Moreover, in that composition range, the effective permeability increased with the Si content(x). Superior soft magnetic property of the high-Si alloys was attributed to both the small magnetocrystalline anisotropy and the low magnetostriction. The effective permeabilities measured at 1㎑ and 5 m0e for crystalline Fe-Cu-Mo-Si-B and Fe-Cu-Nb-Si-B(0.5≤x≤0.8) alloys were about 1∼2 × 10⁴, and it was comparable to that of the zero-magnetostriction Co-based amorphous alloys.

Supplementation of oil-based inactivated H9N2 vaccine with M2e antigen enhances resistance against heterologous H9N2 avian influenza virus infection

Park, J.K.,Lee, D.H.,Cho, C.H.,Yuk, S.S.,To, E.O.,Kwon, J.H.,Noh, J.Y.,Kim, B.Y.,Choi, S.W.,Shim, B.S.,Song, M.K.,Lee, J.B.,Park, S.Y.,Choi, I.S.,Song, C.S. Elsevier Scientific Pub. Co 2014 Veterinary microbiology Vol.169 No.3

Avian influenza virus (AIV) subtype H9N2 has been evolving rapidly and vaccine escape variants have been reported to cause circulation of infections and economic losses. In the present study, we developed and evaluated ectodomain of the AIV matrix 2 (M2e) protein as a supplementing antigen for oil-based inactivated H9N2 vaccine to increase resistance against vaccine escape variants. AIV H9N2 M2e antigen was expressed in Escherichia coli and supplemented to inactivated H9N2 oil emulsion vaccine. Specific pathogen-free chickens received a single injection of inactivated H9N2 oil emulsion vaccines with or without M2e supplementation. At three weeks post vaccination, hemagglutination inhibition tests and enzyme-linked immunosorbent assays were performed to determine serological immune responses. Challenge study using a vaccine escape H9N2 variant was performed to evaluate the efficacy of M2e supplementation. M2e antigen supplemented in oil emulsion vaccine was highly immunogenic, and a single M2e-supplemented vaccination reduced challenge virus replication and shedding more effectively than non-supplemented vaccination.

Interconversion between cyclodimer and cyclotrimer: Synthesis and characterization of cyclo-[Pd(II)Cl₂(N-N)] complexes

Kang, H.J.,Noh, T.H.,Na, Y.M.,Yoo, K.H.,Jung, O.S. Elsevier Sequoia [etc.] 2009 Inorganica chimica acta Vol.362 No.6

The reaction of (COD)PdCl<SUB>2</SUB> (COD=1,5-cyclooctadiene) with (3-Py)<SUB>2</SUB>SiR<SUB>1</SUB>R<SUB>2</SUB> (3-Py=3-pyridyl; R<SUB>1</SUB>=Ph, R<SUB>2</SUB>=Ph (m-pdps); R<SUB>1</SUB>=Ph, R<SUB>2</SUB>=Me (m-pmps)) in acetone affords single crystals consisting of cyclodimers, [PdCl<SUB>2</SUB>((3-Py)<SUB>2</SUB>SiR<SUB>1</SUB>R<SUB>2</SUB>)]<SUB>2</SUB>, whereas the same reaction in a mixture of dichloromethane and ethanol yields amorphous spheres consisting of cyclotrimers, [PdCl<SUB>2</SUB>((3-Py)<SUB>2</SUB>SiR<SUB>1</SUB>R<SUB>2</SUB>)]<SUB>3</SUB>. In a boiling chloroform solution, the cyclodimers are completely converted to cyclotrimers. These cyclotrimers, in the 10-60<SUP>o</SUP>C range, are partly returned to cyclodimers. By contrast, the reaction of (COD)PdCl<SUB>2</SUB> with (3-Py)<SUB>2</SUB>SiR<SUB>1</SUB>R<SUB>2</SUB> (R<SUB>1</SUB>=Bu, R<SUB>2</SUB>=Me (m-pbms); R<SUB>1</SUB>=dodecyl, R<SUB>2</SUB>=Me (m-pddms)) yields amorphous spheres consisting of cyclotrimers irrespective of solvents. Both [PdCl<SUB>2</SUB>(m-pbms)]<SUB>3</SUB> and [PdCl<SUB>2</SUB>(m-pddms)]<SUB>3</SUB> are initially cyclotrimers in chloroform, but they exist as a mixture of cyclodimers and cyclotrimers in solution in the 10-60<SUP>o</SUP>C range. The metallacycles tend to form cyclodimers in the order m-pdps>m-pmps>m-pbms>m-pddms. The equilibrium between cyclodimers and the cyclotrimers is sensitive to solvent, temperature, and concentration as well as molecular structure.

Estimation of radiative forcing by the dust and non-dust content in mixed East Asian pollution plumes on the basis of depolarization ratios measured with lidar

Noh, Y.M.,Muller, D.,Lee, H.,Lee, K.,Kim, K.,Shin, S.,Kim, Y.J. Pergamon Press ; Elsevier [distribution] 2012 Atmospheric environment Vol.61 No.-

The contribution of dust and non-dust aerosols to the lidar observed total backscattering was estimated from the linear particle depolarization ratios (δ<SUB>p</SUB>) under the assumption of externally mixed aerosols. During intensive observation period, the contribution rate of the non-dust aerosol optical depth (AOD, τ) to total AOD increased from 30% on 22 October to 82% on 30 October, which implies that large amount of non-dust particles was transported along with Asian dust storm. Using independent aerosol optics and profiles for dust and non-dust, for the first time, instantaneous aerosol direct radiative forcing (ADRF) of the Asian dust plumes on atmosphere-surface system was quantified. The average ADRF by the dust particles was -31.5 +/- 16.1 (-66.3 +/- 20.2) W m<SUP>-2</SUP> at the surface, -16.5 +/- 8.8 (-11.2 +/- 9.2) W m<SUP>-2</SUP> at the TOA, respectively. The forcing efficiency, defined as the aerosol forcing per unit τ (532 nm), for dust (non-dust) particles was -124.6 +/- 12.2 (-209.4 +/- 59.1) W m<SUP>-2</SUP>/τ<SUB>532</SUB> at the surface and -64.9 +/- 7.8 (-35.1 +/- 28.0) W m<SUP>-2</SUP>/τ<SUB>532</SUB> at the TOA, respectively. Though the contribution of non-dust optical depth to total τ was smaller than the contribution of optical depth from dust to total optical depth, the non-dust particles contributed larger to the radiative forcing at the surface than the dust radiative forcing. This result demonstrates that increased Asian dust radiative forcing can be largely attributed to the presence of non-dust particles mixed into Asian dust layers rather than the radiative forcing by pure dust particles. We also found that non-dust particles play a significant role in stabilizing the dust layer by increasing the radiative heating rates within dust layers.

Two S-wave gap symmetry for single crystals of the superconductor BaFe_1.8Co_0.2As₂

Choi, K.Y.,Kim, S.H.,Choi, C.,Jung, M.H.,Wang, X.F.,Chen, X.H.,Noh, J.D.,Lee, S.I. North-Holland 2010 Physica. C, Superconductivity Vol.470 No.suppl1

To clarify the gap structure of the iron-pnictide superconductors, we synthesized optimally doped single crystals of BaFe<SUB>1.8</SUB>Co<SUB>0.2</SUB>As<SUB>2</SUB>, which had a critical temperature, T<SUB>c</SUB>, of 23.6K. The initial M-H curve was used to find the lower critical field, H<SUB>c1</SUB>. The full range of the temperature dependence of H<SUB>c1</SUB> was explained by using a two S-wave gap symmetry. We estimate the two gap as Δ<SUB>1</SUB>(0)=1.64+/-0.2meV for the small gap and Δ<SUB>2</SUB>(0)=6.20+/-0.2meV for the large gap.

논문 : 노외기계시스템공학 ; 디지털 원추관입기 개발

이규승 ( K. S. Lee ),이동훈 ( D. H. Lee ),조용진 ( Y. J. Cho ),정선옥 ( S. O. Chung ),박원엽 ( W. Y. Park ),노광모 ( K. M. Noh ),장영창 ( Y. C. Chang ) 한국농업기계학회 2010 바이오시스템공학 Vol.35 No.6

This study was performed to design and to construct a digital soil cone index(CI) measuring device replacing conventional analog type devices. The device developed in the study consisted of a load cell, a rotary encoder and a motor with a decelerator as its main parts. The cone speed was controlled lower than 3.0 m/s which keeps the standard suggested by the ASABE S313.3 specification. The experiment was conducted in a soil bin system as well as in various fields. The CI data measured by the developed device were compared with those by an existing measurement device(SC900, Spectrum, USA). Based on the experiments at various field conditions, the CI measuring characteristic of the device was quite similar to that of the conventional device within a acceptable R(2) range of more than 0.5(mean=0.76). It was concluded that the digital cone index measuring device was an effective and comprehensive sensor for measuring soil strength.

(Co0.94- x Fe0.06Mx) 78Si4B18 (M = Cr, Ta, Mo) 비정질 합금의 교류자기특성

강일구,김희중,노태환,한석희,이명복 대한금속재료학회(대한금속학회) 1989 대한금속·재료학회지 Vol.27 No.12

Effective permeability and core loss have been investigated for (Co_(0.94-x)Fe_(0.06)M_x)_78 Si₄B_(18)(M = Cr, Ta, Mo) amorphous alloys in order to clarify soft magnetic properties at high frequencies. At the field of 10 mOe, effective permtabilities are large (e.g. 15,000) at 10 Hz, and decrease drastically with increasing frequency. Decrease of initial permeability due to the increase of frequency is minute at frequencies lower than 100 kHz. The initial permeability increases with the increase of M contents. The core losses of the alloys studied are smaller than that of a permalloy, and are the lowest when M=Cr, higher when M=Ta and the highest when M=Mo.

TRU self-recycling in a high temperature modular helium reactor

Jo, C.K.,Kim, Y.,Noh, J.M.,Venneri, F. North-Holland Pub. Co 2012 Nuclear engineering and design Vol.242 No.-

The Deep Burn Project is developing high burnup fuel based on Ceramically Coated (TRISO) particles, for use in the management of spent fuel Transuranics. This paper evaluates the TRU deep-burn in a High Temperature Reactor (HTR) that recycles its own transuranic production. The DB-HTR is loaded with standard LEU fresh fuel and the self-generated TRUs are recycled into the same core (after reprocessing of the original spent fuel). This mode of operation is called self-recycling (SR-HTR). The final spent fuel of the SR-HTR can be disposed of in a final repository, or recycled again. In this study, a single recycling of the self-generated TRUs is considered. The UO<SUB>2</SUB> fuel kernel is 12% uranium enrichment and the diameter of the kernel is 500μm. TRISO packing fraction of UO<SUB>2</SUB> fuel compact is 26%. In the SR-HTR fuel cycle, it is assumed that the spent UO<SUB>2</SUB> fuel is reprocessed with conventional technology and the recovered TRUs are fabricated into Deep Burn TRISO fuel. The diameter of 200μm is used for the TRU fuel kernel. A typical coating thickness is used. The core performance is evaluated for an equilibrium cycle, which is obtained by cycle-wise depletion calculations. From the analysis results, the equilibrium cycle lengths of Case 1 (5-ring fuel block SR-HTR) and Case 2 (4-ring fuel block SR-HTR) are 487 and 450 EFPDs (effective full power days), respectively. And the UO<SUB>2</SUB> fuel discharge burnups of Case 1 and Case 2 are 10.3% and 10.1%, respectively. Also, the TRU discharge burnups of Case 1 and Case 2 are 64.7% and 63.5%, respectively, which is considered extremely high. The fissile (Pu-239 and Pu-241) content of the self-generated TRU vector is about 52%. The deep-burning of TRU in SR-HTR is partly due to the efficient conversion of Pu-240 to Pu-241, which is boosted by the uranium fuel in SR-HTR. It is also observed that the power distribution is quite flat within the uranium fuel zone. The lower power density in TRU fuel is because the TRU burnup is very high. Also, it is found that transmutation of Pu-239 is near complete in SR-HTR and that of Pu-241 is extremely high in all cases. The decay heat of the SR-HTR core is very similar to the UO<SUB>2</SUB>-only core. However, accumulation of the minor actinides is not avoidable in the SR-HTR core. The extreme high burnup of the Deep Burn fuel greatly reduces the amount of heat producing isotopes that could be problematic in spent fuel repositories (like Pu-238).

Growth of pure wurtzite InGaAs nanowires for photovoltaic and energy harvesting applications

Kang, H.-K.,Kim, J.Y.,Noh, M.-S.,Kang, C.-Y.,Kim, Y.D.,Cho, M.-H.,Song, J.D. Elsevier 2018 Nano energy Vol.53 No.-

<P><B>Abstract</B></P> <P>Vertically aligned and dense InGaAs nanowires were grown on Si (111) substrates by Au-assisted molecular beam epitaxy, and their antireflection characteristics were studied. The bandgap of InGaAs nanowires was tuned to be about 1.0 eV by adjusting the In to Ga ratio. The grown nanowires were vertically aligned with a diameter of ~ 20 nm near the top and ~ 44 nm at the bottom, with a slightly tapered structure. This tapered nanostructure was formed due to the different surface diffusivities and affinities of In and Ga to the Au catalyst. The grown InGaAs nanowires have no significant stacking, kinking, and bending defects. High-resolution transmission electron microscopy study showed that the grown InGaAs nanowires have a pure wurtzite single crystalline structure with the maximum length of ~ 18 µm. Photo-reflectometry measurement showed a significant reduction in the reflectance less than ~ 5% at normal incidence in the wavelength range of 200–1700 nm. In addition, spectroscopic ellipsometry study showed a reduced reflectance at various incident angles of 30–70° in the wavelength range of 200–1100 nm. These optical investigations demonstrate the antireflection characteristics of the InGaAs nanowires. Furthermore, piezoelectric responses were collected from the top of the vertically standing InGaAs nanowires at five different points using piezoelectric force microscopy. The measured area for one point was about 50 nm × 50 nm, and the piezoelectric responses of one or two InGaAs nanowires per point were expected to be measured, as the growth direction was along with the polar <I>c</I>-axis [0001] direction.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Defect-free pure-wurtzite InGaAs nanowires of ~ 1.0 eV bandgap energy with piezoelectric properties of crystal structure were grown on the Si (111) for the application to photovoltaic and mechanical harvesting devices. </LI> <LI> The measured reflectance of InGaAs nanowires showed considerable reduction at incident angles of 30–70° in wide wavelength range of 200–1700 nm, demonstrating the effective antireflection characteristics of the InGaAs nanowires. </LI> <LI> The area of the point measured was about 50 nm × 50 nm; the piezoelectric responses of one or two InGaAs nanowires per point were expected to be measured, as the growth direction was along the polar <I>c</I>-axis [0001] direction. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Si film electrodes containing surface-modified Cu current collectors prepared by a low temperature oxidation-reduction process

Cho, G.B.,Jeong, J.S.,Im, Y.M.,Choi, H.K.,Noh, J.P.,Kim, J.K.,Ahn, H.J.,Nam, T.H.,Kim, K.W. Pergamon Press [etc.] 2016 Vacuum Vol.132 No.-

<P>A low-temperature oxidation-reduction process was used to modify the surface of a Cu current collector (foil) for a Si film electrode. The surfaces of the modified Cu foils were investigated under various oxidation-reduction conditions, and the electrochemical properties of Si film electrodes containing the surface modified foils were evaluated. Various nanostructures were found to have formed on the surface; for example, Cu(OH)(2) needles, CuO flowers, and CuO plates formed on Cu-foil surfaces oxidized at 313 K for 1, 10, and 30 min, respectively. Furthermore, these nanostructures were transformed to coral-like Cu2O structures after reduction at 673 K. The amount of Cu2O and the surface roughness decreased on increasing reduction time. The Si film electrode containing a Cu foil reduced for 6 h showed the best electrochemical performance (83.5% of the initial efficiency and 74.8% of capacity retention) due to the small amount of Cu2O and the formation of coral-like structures. (C) 2016 Elsevier Ltd. All rights reserved.</P>