Aluminizing and Boroaluminizing Treatments of Mar-M247 and Their Effect on Hot Corrosion Resistance in Na₂SO₄-NaCl Molten Salt

Cho, J.H.,Kim, T.W.,Son, K.S.,Yoon, J.H.,Kim, H.S.,Leisk, G.G.,Mitton, D.B.,Latanision, R.M. 대한금속재료학회 2003 METALS AND MATERIALS International Vol.9 No.3

The effect of surface modifications of Mar-M247 superalloy on hot corrosion resistance was examined in Na₂SO₄-NaCl molten salt. The Mar-M247 was aluminized and boroaluminized by pack cementation in Ar and underwent a cyclic hot corrosion test in Na₂SO₄-NaCl molten salt. The XRD results showed that a Ni2Al3 phase was formed between the aluminized layer and the substrate when the surface modification temperature was below 1273 K. However, a NiAl phase formed when the temperature was above 1273 K. The intensity of the XRD peak in the NiAl phase increased after post heat treatment. Hot corrosion resistance increased for the specimens containing NiAl rather than Ni₂Al₃ phase. The ductile NiAl phase suppressed the potential for crack initiation during thermal cycling. Post heat treatment increased the corrosion resistance of the aluminized layer for Mar-M247, which underwent surface modification at 1273 K and above. In the boroaluminized Mar-M247 specimens, corrosion resistance decreased as a result of the blocking of outward diffusion of Cr by boron and decreased cohesion between the oxide scale and the aluminized layer during thermal cycling.

Iturin produced by Bacillus pumilus HY1 from Korean soybean sauce (kanjang) inhibits growth of aflatoxin producing fungi

Cho, K.M.,Math, R.K.,Hong, S.Y.,Asraful Islam, S.Md.,Mandanna, D.K.,Cho, J.J.,Yun, M.G.,Kim, J.M.,Yun, H.D. Butterworths ; Taylor Francis ; Elsevier Science 2009 FOOD CONTROL Vol.20 No.4

A new strain of Bacillus pumilus, designated HY1, was isolated from Korean soybean sauce (kanjang). This classification was based on morphological, physiological, and chemotaxonomic features of the organism that identified it as a Gram-positive bacillus, and confirmed by 16S rDNA based phylogenetic analysis. Strain HY1 showed strong antifungal activity against the aflatoxin-producing fungi Aspergillus flavus and Aspergillus parasiticus, two common contaminants of fermented soybean foods. MALDI-TOF mass analysis revealed that the antifungal compound was similar to the known lipopeptide iturin. Iturin purified from strain HY1 had three isoforms with protonated masses of m/z 1,043.4, 1,057.4, and 1,071.4, and different structures in combination with Na<SUP>+</SUP> ion using MALDI-TOF MS. Purified iturin from HY1 also exhibited antifungal activity against A. flavus and A. parasiticus.

돼지의 선발에 있어서 능력검정 방법에 따른 육종가 및 유전적 개량량의 변화

조규호,김시동,김명직,이일주,전광주 한국동물자원과학회 2001 한국축산학회지 Vol.43 No.6

본 연구에서는 이유시체중(㎏), 90㎏ 도달일령을 대상형질로 하여 폐쇄돈군에서 이유시 체중을 기초로 5가지의 선발방법에 따라 선발된 선발축의 산육 능력을 검정하여 검정이 완료된 개체들에 대해 유전능력 평가를 실시한후 검정대상 선발두수의 크기에 따른 유전적 개량량을 비교하여 이상적인 검정방법을 찾고자 실시하였다. 시뮬레이션 결과 90㎏ 도달일령에 대한 육종가 추정치의 변화는 Method Ⅴ그룹에서 -36.2일의 단축효과를 보였으며 세대당 유전적 개량량 또한 Method Ⅴ그룹에서 -7.5일로 가장 높은 개량을 보였다. 따라서 개량적인 측면에 있어서는 전수검정을 실시하는 것이 가장 좋을 것으로 사료되지만 농장의 검정능력이나 전수검정을 실시할 때 드는 초과비용에 대한 경제적인 분석은 더 연구되어져야 될 것으로 사료된다. This study was carried out to find the ideal testing method by comparing predicted breeding values, and genetic gain by the size of testing group. Tested traits were weaning weight and days to 90㎏. Five methods for selecting testing group were adopted: Method Ⅰ (MⅠ ; 30% selected based on litter weight at weaning for female, and 30% selected based on individual weight at weaning for mail), Method Ⅱ (MⅡ ; 30% selected based on individual weight at weaning for female and male, respectively), Method Ⅲ (MⅢ ; 50% selected based on individual weight at weaning for female and male, respectively), Method Ⅳ (MⅣ ; 70% selected based on individual weight at weaning for female and male, respectively), Method Ⅴ (MⅤ ; all piglets were tested). Genetic ability was evaluated by multiple trait animal model using MTDFREML package. Based on the predicted breeding values for days to 90㎏, the next generation was selected up to 5th generation. The above procedure were repeated and simulated by 4 times. The results obtained in the present study are summarized as follows; Phenotypic mean and predicted breeding values mean of days to 90㎏ was 114.3, -27.8, 113.7, -27.0, 107.5, -32.6, 105.7, -34.4, 103.7 and -36.2 days for MⅠ, MⅡ, MⅢ, MⅣ and MⅤ, respectively. Phenotypic and predicted breeding values variance of days to 90㎏ was 20.9, 4.1, 19.0, 3.4, 15.3, 1.8, 13.8, 1.7, 13.3 and 1.2 days for MⅠ, MⅡ, MⅢ, MⅣ and MⅤ, respectively. Genetic gain of days to 90㎏ was -6.2, -6.0, -7.1, -7.3 and -7.5 days for MⅠ, MⅡ, MⅢ, MⅣ and MⅤ, respectively. In all case, Method Ⅴ group, all piglets be tested, is the most efficient for improving the target economic traits.

Solubility of oxcarbazepine in eight solvents within the temperature range T=(288.15-308.15)K

Nam, K.,Ha, E.S.,Kim, J.S.,Kuk, D.H.,Ha, D.H.,Kim, M.S.,Cho, C.W.,Hwang, S.J. Academic Press 2017 The Journal of chemical thermodynamics Vol.104 No.-

In this study, the solubility of oxcarbazepine in pure methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, acetone, acetonitrile, and tetrahydrofuran was analysed across the temperature range of 288.15-308.15K under atmospheric pressure by using a solid-liquid equilibrium method. The experimental values obtained data were correlated using the modified Apelblat model at each temperature. The mole fraction solubility of oxcarbazepine in all eight pure solvents increased gradually in a temperature-dependent manner. The highest mole fraction solubility of 3.08x10<SUP>-3</SUP> at 308.15K was observed for tetrahydrofuran, followed by acetone (1.82x10<SUP>-3</SUP> at 308.15K), acetonitrile (1.22x10<SUP>-3</SUP> at 308.15K), methanol (1.11x10<SUP>-3</SUP> at 308.15K), ethanol (6.17x10<SUP>-4</SUP> at 308.15K), 1-butanol (6.17x10<SUP>-4</SUP> at 308.15K), 1-propanol (6.16x10<SUP>-4</SUP> at 308.15K), and 2-propanol (4.13x10<SUP>-4</SUP> at 308.15K). The experimental solubility in all solvents correlated well with that calculated using the modified Apelblat equation across the temperature range of (288.15-308.15)K. Therefore, the experimental solubility and correlation equations established in this study could be useful during the crystallization/purification, pre-formulation, and formulation stages of oxcarbazepine production in laboratories and related industries.

Control of Thermoelectric Properties through the addition of Ag in the Bi0.5 Sb1.5 Te3Alloy

( J. K. Lee ),( S. D. Kim ),( M. W. Oh ),( S. H. Cho ),( B. K. Min ),( H. W. Lee ),( M. H. Kim ) 대한금속재료학회 ( 구 대한금속학회 ) 2010 ELECTRONIC MATERIALS LETTERS Vol.6 No.4

In this study, the thermoelectric properties of the Ag-doped Bi0.5Sb1.5Te3 compounds were investigated in the temperature range from 323 K to 573 K. Ingots were fabricated by a conventional melting process and the powder crushed from ingots was then sintered using a hot-pressing method. The temperature dependence of the Seebeck coefficient and the electrical conductivity of the Ag-doped Bi0.5Sb1.5Te3compound are characteristic of degenerate semiconductors, which is fairly different from the conventional Bi0.5Sb1.5Te3 compound. The power factor (α 2 σ) of the quaternary compound was larger than that of the ternary, which is mainly due to the increase in the electrical conductivity with doping content of Ag. The thermal conductivity was greater than that of the Ag-freeBi0.5Sb1.5Te3compound in the temperature range from 323 K to 523 K. The lattice thermal conductivity showed low values throughout the temperature range. The maximum value of the dimensionless figure of merit (ZT) of the 0.05 wt. % Ag-doped compound and the ternary alloy were 1.2 at 373 K and 0.88 at 323 K, respectively. Each of the maximum peak ZT shifts to a higher temperature region with increases in the doping content of Ag. This is likely due to the control of the lattice thermal conductivity by the twin structure, which had a nano-ordered layer.

Comparison of 90‐day case‐fatality after ischemic stroke between two different stroke outcome registries using propensity score matching analysis

Yu, K‐,H.,Hong, K‐,S.,Lee, B‐,C.,Oh, M‐,S.,Cho, Y‐,J.,Koo, J‐,S.,Park, J‐,M.,Bae, H‐,J.,Han, M‐,K.,Ju, Y‐,S.,Kang, D‐,W.,Appelros, P. Blackwell Publishing Ltd 2011 Acta neurologica Scandinavica Vol.123 No.5

<P>Yu K‐H, Hong K‐S, Lee B‐C, Oh M‐S, Cho Y‐J, Koo J‐S, Park J‐M, Bae H‐J, Han M‐K, Ju Y‐S, Kang D‐W, Appelros P, Norrving B, Terent A. Comparison of 90‐day case‐fatality after ischemic stroke between two different stroke outcome registries using propensity score matching analysis. 
Acta Neurol Scand: 2011: 123: 325–331. 
© 2010 John Wiley & Sons A/S.</P><P><B>Background – </B> It has not been clarified whether the disparity in ischemic stroke outcome between populations is caused by ethnic and geographic differences or by variations in case mix. Propensity score matching (PSM) analysis can overcome some analytical problems but is rarely used in stroke outcome research. This study was to compare the ischemic stroke case‐fatality between two PSM cohorts of Sweden and Korea.</P><P><B>Methods – </B> Prognostic variables related to baseline characteristics and stroke care were included in our PSM model. Then, we selected 7675 Swedish and 1220 Korean patients with ischemic stroke from each stroke registers and performed one‐to‐one matching based on propensity scores of each patient.</P><P><B>Results – </B> After PSM, all measured variables were well balanced in 1163 matched subjects, and the 90‐day case‐fatality was identical 6.2% (HR 0.997, 95%CI 0.905–1.099) in Sweden and Korea.</P><P><B>Conclusions – </B> No difference is found in the 90‐day case‐fatality in propensity score‐matched Swedish and Korean patients with ischemic stroke.</P>

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.

Relationship between Stress Gene Polymorphisms and Litter Size by AI in Pigs

Jin, H.J.,Kim, I.C.,Wee, M.S.,Yeon, S.H.,Kim, C.D.,Lee, S.S.,Cho, C.Y.,Cho, S.R.,Son, D.S.,Park, C.K. 韓國受精卵移植學會 2007 한국동물생명공학회지 Vol.22 No.4

This study was performed to investigate the relationship between PSS-HSP70 gene polymorphism and artificial insemination (AI) reproductivity in the pigs. The RFLP polymorphism of PSS and the SSCP polymorphisms of HSP70 K1, K3 and K4 PCR product were detected different patterns. In the experiment for AI of fresh semen, spring and fall season showed higher litter size born of 10.89 head than 10.47 head of summer season. Landrace was showed higher litter size of 9.96 head than that of Duroc and Yorkshire (p<0.05). Stress relating PSS and HSP70 polymorphism of PSS-Normal, HSP70 K1-BB, K3-AB, K4-AA showd a highest litter size born of 10.97 head and litter size born alive of 10.69 head than that of the other polymorphisms(p<0.05). In the experiment for AI of frozen semen, effects of season and pig breeds were not showed for litter size born. The stress relating polymorphism of PSS-Carrier, HSP70 K1-BB, K3-BB, K4-AB showed highest litter size born of 11.29 head and litter size born alive of 10.82 head and PSS-Normal, HSP70 K1-BB, K3-AB, K4-AA showed the lowest litter size born of 8.48 head and litter size born alive of 7.33 head than that of the other polymorphisms(p<0.05). These results suggest that AI litter size born for the stress of forzen thawed semen may be affected by PSS and HSP70 polymorphism in pigs.

Relationship between Stress Gene Polymorphisms and Litter Size by AI in Pigs

H. J. Jin,I. C. Kim,M. S. Wee,S. H. Yeon,C. D. Kim,S. S. Lee,C. Y. Cho,S. R. Cho,D. S. Son,C. K. Park,Z. D. Li 사단법인 한국동물생명공학회 2007 한국동물생명공학회지 Vol.22 No.4

This study was performed to investigate the relationship between PSS-HSP70 gene polymorphism and artificial insemination (AI) reproductivity in the pigs. The RFLP polymorphism of PSS and the SSCP polymorphisms of HSP70 K1, K3 and K4 PCR product were detected different patterns. In the experiment for AI of fresh semen, spring and fall season showed higher litter size born of 10.89 head than 10.47 head of summer season. Landrace was showed higher litter size of 9.96 head than that of Duroc and Yorkshire(p<0.05). Stress relating PSS and HSP70 polymorphism of PSS-Normal, HSP70 K1-BB, K3-AB, K4-AA showd a highest litter size born of 10.97 head and litter size born alive of 10.69 head than that of the other polymorphisms(p<0.05). In the experiment for AI of frozen semen, effects of season and pig breeds were not showed for litter size born. The stress relating polymorphism of PSS-Carrier, HSP70 K1-BB, K3-BB, K4-AB showed highest litter size born of 11.29 head and litter size born alive of 10.82 head and PSS-Normal, HSP70 K1-BB, K3-AB, K4-AA showed the lowest litter size born of 8.48 head and litter size born alive of 7.33 head than that of the other polymorphisms(p<0.05). These results suggest that AI litter size born for the stress of forzen thawed semen may be affected by PSS and HSP70 polymorphism in pigs.

Evolution of carbides in cold-work tool steels

Kim, H.,Kang, J.Y.,Son, D.,Lee, T.H.,Cho, K.M. Elsevier 2015 Materials characterization Vol.107 No.-

This study aimed to present the complete history of carbide evolution in a cold-work tool steel along its full processing route for fabrication and application. A sequence of processes from cast to final hardening heat treatment was conducted on an 8% Cr-steel to reproduce a typical commercial processing route in a small scale. The carbides found at each process step were then identified by electron diffraction with energy dispersive spectroscopy in a scanning or transmission electron microscope. After solidification, MC, M<SUB>7</SUB>C<SUB>3</SUB> and M<SUB>2</SUB>C carbides were identified and the last one dissolved during hot compression at 1180<SUP>o</SUP>C. In a subsequent annealing at 870<SUP>o</SUP>C followed by slow cooling, M<SUB>6</SUB>C and M<SUB>23</SUB>C<SUB>6</SUB> were added, while they were dissolved in the following austenitization at 1030<SUP>o</SUP>C. After the final tempering at 520<SUP>o</SUP>C, fine M<SUB>23</SUB>C<SUB>6</SUB> precipitated again, thus the final microstructure was the tempered martensite with MC, M<SUB>7</SUB>C<SUB>3</SUB> and M<SUB>23</SUB>C<SUB>6</SUB> carbide. The transient M<SUB>2</SUB>C and M<SUB>6</SUB>C originated from the segregation of Mo and finally disappeared due to attenuated segregation and the consequent thermodynamic instability.