• The Transactions of the Korean Institute of Electrical Engineers C
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• v.55 no.10
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• pp.461-466
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• 2006

In the present work, we investigated the photodissolution and photodiffusion effect on the interface of Ag/chalcogenide $As_{40}Ge_{10}Se_{15}S_{35}$ thin film by measuring the absorption coefficient, the optical density, the resistance change of Ag layer. It was found that the photodissolutioniphotodiffution ratio depends on the magnitude of photon energy absorbed in the chalcogenide thin film and the depth of photodiffution was proportional to the square root of the exposed time. Also, we have investigated the holographic grating formation with P-polarization states on chalcogenide $As_{40}Ge_{10}Se_{15}S_{35}$ thin film and $As_{40}Ge_{10}Se_{15}S_{35}/Ag$ double layer structure thin film. Holographic gratings have been formed using He-Ne laser (632.8 nm) which have a smaller energy than the optical energy gap, $E_g\;_{opt}$ of the film, i. e., an exposure of sub-bandgap light $(h{\upsilon} under P-polarization. As the results, we found that the diffraction efficiency on $As_{40}Ge_{10}Se_{15}S_{35}/Ag$ double layer structure thin film was more higher than that on single $As_{40}Ge_{10}Se_{15}S_{35}$ thin film. Also, we obtained that the maximum diffraction efficiency was 0.27 %, 1,000 sec on $As_{40}Ge_{10}Se_{15}S_{35}\;(1{\mu}m)/Ag$ (10 nm) double layer structure thin film by (P: P) polarized recording beam. It will offer lots of information for the photodoping mechanism and the analyses of chalcogenide thin films.

• Food Science of Animal Resources
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• v.23 no.2
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• pp.161-167
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• 2003

Identification of salmonellosis-infected commercial poultry flocks has become a pivotal component of efforts to reduce incidence of egg-associated transmission of S. enteritidis and S. typhimurium to humans. As a basic study for sanitary control of S. enteritidis and S. typhimurium, main food-borne pathogenic bacteria in eggs produced by domestic hens, commercial egg samples were tested for specific antibodies to whole cells of S. enteritidis and S. typhimurium and outer membrane protein(OMP) of S. typhimurium by ELISA to detect infection of S. enteritidis and S. typhimurium in various groups of hens. When the antibody titers of yolks from three commercial brand eggs were tested after diluting in the ratio from 1:100 to 1:1,600 with double dilution method, ELISA values of the specific antibodies could be shown as differences in dilution patterns by comparing with negative control egg. When the antibody titers of the yolks from two commercial brand eggs were tested after diluting in the ratio of 1:200 and 1:1,000, ELISA values of specific antibodies were different among same brand eggs. When the antibody titers of yolks from five eggs sampled randomly from twenty one commercial brand eggs were tested after diluting in the ratio of 1:1,000, ELISA value of the specific antibodies were shown generally high. ELISA values of 28.5, 30, and 28.5% of yolks from 21 brand eggs were shown low and similar to negative control egg in antibody titers to whole cells of S. enteritidis and S. typhimurium and OMP of S. typhimurium, respectively. The results demonstrated that ELISA test of egg yolk antibody could provide a highly sensitive indicator to detect contamination of S. typhimurium and S. enteritidis in poultry, and could be used effectively to reduce incidence of S. typhimurium and S. enteritidis infection in poultry.

• Transactions on Electrical and Electronic Materials
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• v.4 no.6
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• pp.13-16
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• 2003

Mn-doped $ZnGa_{2}O_{4}$:$Mn^{2+}$ (M=S, Se) thin film phosphors have been grown using a pulsed laser deposition technique under various growth conditions. The structural characterization carr~ed out on a series of $ZnGa_{2}O_{4}$:$Mn^{2+}$ (M=S, Se) films grown on MgO(l00) substrates usmg Zn-rich ceramic targets. Oxygen pressure was varied from 50 to 200 mTorr and Zn/Ga ratio was the function of oxygen pressure. XRD patterns showed that the lattice constants of the $ZnGa_{2}O_{4}$:$Mn^{2+}$ (M=S, Se) thin film decrease with the substitution of sulfur and selenium for the oxygen in the $ZnGa_2O_4$. Measurements of photoluminescence (PL) properties of $ZnGa_{2}O_{4}$:$Mn^{2+}$ (M=S, Se) thin films have indicated that MgO(100) is one of the most promised substrates for the growth of high quality $ZnGa_2O_{4-x}M_{x}$:$Mn^{2+}$ (M=S, Se) thin films. In particular, the incorporation of Sulfur or Selenium into $ZnGa_2O_4$ lattice could induce a remarkable increase in the intensity of PL. The increasing of green emission intensity was observed with $ZnGa_2O_{3.925}Se_{0.075}:$Mn^{2+}$ and $ZnGa_2O_{3.925}S_{0.05}$:$Mn^{2+}$ films, whose brightness was increased by a factor of 3.1 and 1.4 in comparison with that of $ZnGa_{2}O_{4}$:$Mn^{2+}$ films, respectively. These phosphors may promise for application to the flat panel displays.

• Proceedings of the KIEE Conference
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• 2002.07c
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• pp.1584-1586
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• 2002

CuIn$Se_2$ (CIS) and related compounds such as Cu($In_xGa_{1-x})Se_2$(CIGS) have been studied by their potential for use in photovoltaic devices. CIS thin film materials which have high absorption coefficient and wide bandgap, have attracted much attention as an alternative to crystalline and amorphous silicon solar cells currently in use. Cu-rich CIGS film have very low resistivity, due to coexistence of the semimetallic $Cu_{2-x}Se$. In-rich CIGS films show high resistivity, since these films are compensated films without the $Cu_{2-x}Se$ phase. Optical properties of the CIGS films also change in accordance with the resistivity for the Cu/(In+Ga) ratio. The Cu-rich films have different spectra from In-rich films in near infrared wavelengths.

• 한국신재생에너지학회:학술대회논문집
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• 2007.11a
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• pp.270-273
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• 2007

In this report, Indium-free and Indium-reduced thin film materials for solar absorber were studied in order to search alternative materials for thin film solar cell. The films of $Cu_2ZnSnSe_4$ and $Cu_2ZnSnSe_2$ were deposited using mixed binary chalcogenides powders. From the film bulk analysis result, it is observed that Cu concentration is a function of substrate temperature as well as CuSe mole ratio in the target. Under optimized conditions, $Cu_2ZnSnSe_4$ and $Cu_2ZnSnSe_2$ thin films grow with strong (112), (220/204) and (312/116) reflections. Films are found to exhibit a high absorption coefficient of $10^4$ $cm^{-1}$. $Cu_2ZnSnSe_4$ film shows a 1.5 eV band gap. On the other side, an increasing of optical band gap from 1.0 eV to 1.25 eV ($CuInSnSe_2$) is found to be proportional with an increasing of Zn concentration. All films have a p-type semiconductor characteristic with a carrier concentration in the order of $10^{14}$ $cm^{-3}$, a mobility about $10^1$ $cm^{2{\cdot}-1.}S^{-1}$ and a resistivity at the range of $10^2-10^6$ ${\Omega}{\cdot}m$.

• Tuberculosis and Respiratory Diseases
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• v.79 no.4
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• pp.295-301
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• 2016

Background: Specific immunoglobulin E (IgE) sensitization to staphylococcal enterotoxin (SE) has been recently considered to be related to allergic disease, including asthma. Despite studies on specific IgE (sIgE) to SE and its relationship to asthma diagnosis and severity, the association of sIgE to SE with airway hyperresponsiveness (AHR) remains unclear. Methods: We enrolled 81 asthma patients admitted to the Severance Hospital in Korea from March 1, 2013, to February 28, 2015 and retrospectively reviewed the electronic medical records of the enrolled subjects. The serum levels of sIgE to SE (A/B) of all subjects was measured using the ImmunoCAP 250 (Phadia) system with SE-sIgE positive defined as >0.10 kU/mL. Results: The SE-sIgE level was not significantly correlated with asthma severity (forced expiratory volume in 1 second [$FEV_1$], $FEV_1$/forced vital capacity, sputum eosinophils, and serum eosinophils), whereas the SE-sIgE level in patients with positive AHR ($mean{\pm}standard$ error of the mean, $0.606{\pm}0.273kU/mL$) was significantly higher than that in patients with negative AHR ($0.062{\pm}0.015kU/mL$, p=0.034). In regression analysis, SE sensitization (sIgE to SE ${\geq}0.010kU/mL$) was a significant risk factor for AHR, after adjustment for age, sex, $FEV_1$, and sputum eosinophils (odds ratio, 7.090; 95% confidence interval, 1.180-42.600; p=0.032). Prevalence of SE sensitization was higher in patients with allergic rhinitis and non-atopic asthma patients, as compared to patients without allergic rhinitis and atopic asthma patients, respectively, but without statistical significance. Conclusion: SE sensitization is significantly associated with AHR.

• Journal of the Korean Electrochemical Society
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• v.14 no.1
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• pp.1-8
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• 2011

Ionic liquids are room-temperature molten salts, composed of organic mostly of organic ions that may undergo almost unlimited structural variation. We approach the new aspects of ionic liquids in applications where the semiconductor nanoparticles used as sensitizers of solar cells. We studied the effects of ionic liquids as capping ligand and/or solvent, on the morphology and phase of the CdSe/ZnS nanoparticles. Colloidal CdSe/ZnS nanoparticles were synthesized using a series of imidazolium ionic liquids; 1-R-3-methylimidazolium bis(trifluoromethylsulfonyl) imide ([RMIM][TFSI]), where R = ethyl ([EMIM]), butyl ([BMIM]), hexyl ([HMIM]), octyl ([OMIM]). The average size of nanoparticles was 8~9 nm, and both zinc-blende and wurtzite phase was produced. We also synthesized the nanoparticles using a mixture of trihexyltetradecylphosphonium bis(trifluoromethylsulfonyl)imide ([$P_{6,6,6,14}$][TFSI]) and octadecene (ODE). The CdSe/ZnS nanoparticles have a smaller size (5.5 nm) than that synthesized using imidazolium, and with a controlled phase from zinc-blende to wurtzite by increasing the volume ratio of [$P_{6,6,6,14}$][TFSI]. For the first time, the phase and size control of the CdSe/ZnS nanoparticles was successfully demonstrated using those ionic liquids.

• The Korean Journal of Zoology
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• v.13 no.1
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• pp.15-20
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• 1970

The present study was undertaken in an attempt to see if the segregation frequency of a third chromosome was changed by changing the sex chromosome which were free of SD in the second chromosome. The eight genotype males having different sex chromosome constitution each were constructed by appropriate matings and the two standard laboratory stocks of Drosophila melanogaster, e and se were used as the third chromosome recessive markers for the present experiment. The results of the present investigation are given below: 1. The k values which are the proportion of the se third chromosomes recovered among progeny flies from the mating of se/e males to e females were highly signiicantly different among the four genotypes and between the two sexes,and the interaction of genotype and sex was significantly different. Thus the setregation frequency of the se third chromosome in the male, when made heterozygous with the e third chromosome, was dependent upon the sex chromosome constitution. 2. Both of the k(Woman) and the k(man) remains roughly constant among genotypes. 3. The sex ratio o the se progeny class was highly significantly heterogeneous among the four genotypes but it was homogeneous for the e progeny class. 4. The values of the k(man) and the sex ratio of the se progeny class, on the average, were higher than that of the k(Woman) and of the e progeny class, respectively. 5. Those phenomena suggest that some sort of prezygotic selection could be operating such that the combination of the e third chromosome and the Y chromosome tends to be eliminated before fertilization. This tendency argues for a re-examination of the viability estimations of Drosophila melanogaster.

• Journal of Nutrition and Health
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• v.31 no.3
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• pp.324-332
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• 1998

Studies on relationships between antioxidant nutrients and various chronic diseases are increasing. In this study , serum concentrations of antioxidant minerals(Se, Cu, Zn & Mn) wee measured and compared among normal Korean adults. The ICP -MS method was employed to measure mineral concentrations. The subjects consisted of 329 healthy adults(154 men & 175 women) aged 20-79 years. The mean serum concentration appeared to be 26.4$\pm$0.41 (Se), 89.6$\pm$1.53(Cu), 113.3$\pm$1.56(Zn) & 0.34$\pm$0.05(Mn)$\mu\textrm{g}$/㎗ for men and 24.5$\pm$0.32(Se), 95.1$\pm$1.58(Cu), 133.6$\pm$1.79(Zn) & 0.35$\pm$0.02(Mn) $\mu\textrm{g}$/㎗ for women respectively. Among antioxidant minerals measured, the mean serum levels of Se and Zn were higher in men than in women(p<0.001), whereas that of Cu was higher in women(p<0.01). No significant difference between sex was observed for the mean Mn concentrations. The mean serum levels of Se(p<0.01) and Zn(p<0.05) decreased significantly in the 60's women On the other hand, the Mn concentrations in the 60's of women showed a significant increase(p<0.01). This difference seems to be due to the changes in menopausal status . The Cu levels in men showed a consistent increase with advancing age. The mean Cu/Zn ratios were 0.83 $\pm$0.04 for men and 0.95$\pm$0.02(p<0.01) for women respectively. The fact that this ratio increased significantly at the 60's of men (1.26 ; p<0.001) requires further study in relation to chronic diseases. When analyzed by stepwise multiple regression, drinking positively influenced serum Se and Cu levels for both men and women , smoking, however, negatively influenced all serum mineral levels for women. Further studies are needed to clarify precise roles of antioxidant minerals, their interactions and their relation to disease status.

• Journal of Animal Environmental Science
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• v.18 no.3
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• pp.145-150
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• 2012

This study was conducted to measure methane ($CH_4$) and nitrous oxide ($N_2O$) emissions from the 6 month old litter stockpile used for korean native cattle (Hanwoo) from August 3, 2007 to October 4, 2007. Daily mean $CH_4$ emissions was peaked to 273.013 ${\mu}g\;m^{-2}\;s^{-1}$ (SE : ${\pm}1.047{\mu}g\;m^{-2}\;s^{-1}$) on first day and then gradually decreased to 2.309 ${\mu}g\;m^{-2}\;s^{-1}$ (SE : ${\pm}0.061{\mu}g\;m^{-2}\;s^{-1}$) at the end of this experiment. Daily mean $N_2O$ emissions was as little as 0.269 ${\mu}g\;m^{-2}\;s^{-1}$ (SE : ${\pm}0.018{\mu}g\;m^{-2}\;s^{-1}$) on first day, but exponentially increased up to 3.569 ${\mu}g\;m^{-2}\;s^{-1}$ (SE : ${\pm}0.454{\mu}g\;m^{-2}\;s^{-1}$) on 43rd day and then slowly decreased to 1.888 ${\mu}g\;m^{-2}\;s^{-1}$ (SE : ${\pm}0.012{\mu}g\;m^{-2}\;s^{-1}$) at the end of this experiment. Carbon dioxide equivalent ($CO_2$-eq), calculated by global warming potentials of $CH_4$ or $N_2O$, of $CH_4$ on first day occupied approximately 99% of sum of $CO_2$-eq of $CH_4$ and $N_2O$. Methane emissions decreased and $N_2O$ emissions increased so that $CO_2$-eq ratio of $CH_4$ to $N_2O$ was 50:50 on 34th day. The effect of $N_2O$ on the ratio was increase thereafter. The ratio of daily mean $CH_4$ and $N_2O$ emissions to daily error of the mean was calculated to find daily fluctuation of $CH_4$ and $N_2O$ emissions. The ratio of $CH_4$ was less than 1.0% till 11th day but increased to 10.9% on 57th day. The ratio of $N_2O$ (0.4%~51.0%) was higher than that of $CH_4$, showing high in early stage and then gradually decrease, which was different from the pattern of $CH_4$. The ratio of daily mean emissions to daily error of the mean was little in case of active $CH_4$ or $N_2O$ generation period, which would be caused by the temporal and spatial heterogeneity of composting process. Hence more air supply on early stage to decrease $CH_4$ generation and proper turning to reduce spatial heterogeneity are needed to mitigate greenhouse gas emissions.