• Journal of the Korean institute of surface engineering
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• v.42 no.3
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• pp.128-132
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• 2009

Transparent conducting thin films of indium tin oxide(ITO) co-sputtered with aluminum-doped zinc oxide(AZO) were deposited on glass substrate by dual magnetron sputtering. It was found that the electrical properties and structural characteristics of the films are significantly changed according to the sputtering power of the AZO target. The IAZTO film prepared with D.C power of ITO at 100 W and R.F power of AZO at 50 W shows an electrical resistivity of $4.6{\times}10^{-4}{\Omega}{\cdot}cm$ and a sheet resistance of $30{\Omega}/{\square}$ (for 150 nm thick). Besides of the improvement of the electrical properties, compared to the ITO films deposited at the same process conditions, the IAZTO films have very smooth surface, which is due to the amorphous nature of the films. However, the electrical conductivity of the IAZTO films was found to be deteriorated along with the crystallization in case of the high temperature deposition (above $310^{\circ}C$). In this work, high quality amorphous transparent conductive oxide layers could be obtained by mixing AZO with ITO, indicating possible use of IAZTO films as the transparent electrodes in OLED and flexible display devices.

• Journal of the Korean Chemical Society
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• v.13 no.1
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• pp.49-55
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• 1969

X-ray Fluorescence Spectrographic method has been applied for the rapid determination of main components, such as $SiO_2$, $Al_2O_3$, $Fe_2O_3$, CaO, MgO and $K_2O$ in Silicate Minerals. In this method, Boric Acid was used as a binder after fusion with Lithium Tetraborate in the briquet-making process. The Lithium Flubride, Ammonium di-Hydrogen Phosphate and Ethylene Diamine d-Tartrate crystals were used with Scintillation counter and Gas Flow counter as the detectors. Several influences on this method were discussed, including the particle size of samples and reducing of the matrix effects by dilution with Boric Acid and addition of Lanthanum Oxide with the diluent. In order to test the reproducibility of this method described above, the determination of the same kind of samples were carried out repeatedly, and the results obtained were presented in the table. Calibration curves for each element were presented, and the application of the method was tested with International Rock Standard T-Ⅰ. All the results obtained by X-Ray Fluorescence Spectrographic method were compared with the results by conventional chemical method.

• Journal of the Korean Ceramic Society
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• v.38 no.12
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• pp.1162-1166
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• 2001

NiZn-ferrite was synthesized from waste catalysts, which were produced from styrene monomer process and buried underground as an industrial wastes, and its magnetic properties were investigated. Nickel oxide and zinc oxide powders were mixed with finely ground waste catalysts, and spinel type ferrite was obtained by calcination at 900$\^{C}$ and sintering at 1230$\^{C}$ for 5 hours. The intial permeability was measured and reflection loss was calculated from S-parameters for the composition of Ni$\_$x/Zn$\_$1-x/Fe$_2$O$_4$(x=0.36, 0.50, 0.66). NiZn-ferrite synthesized from waste iron oxide catalyst showed a feasibility for the use as electromagnetic wave absorber in X-band.

• Journal of Hydrogen and New Energy
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• v.27 no.1
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• pp.83-94
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• 2016

Performance of absorbent for post-combustion $CO_2$ capture was measured and discussed. Fully saturated fresh absorbent (P2-15F) and absorbents sampled from absorption and regeneration reactor of continuous $CO_2$ capture process, P2-15A, P2-15R, respectively, were used as representative absorbents. Small scale fluidized bed reactor (0.05 m I.D., 0.8 m high) which can measure exhaust gas concentration and weight change simultaneously was used to analyze regeneration characteristics for those absorbents. Exhausted moles of $CO_2$ and $H_2O$ were measured with increasing temperature. $H_2O/CO$ ratio and working capacity were determined and discussed to confirm reason of reactivity decay after continuous operation. Moreover, possibility of side reaction was checked based on the $H_2O/CO_2$ mole ratio. Finally, suitable regeneration temperature range was confirmed based on the trend of working capacity with temperature.

• Journal of Soil and Groundwater Environment
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• v.21 no.2
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• pp.8-14
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• 2016

We compared the plausible reaction mechanism and quantitative efficiency of highly self-organized TiO₂ nanotube (ntTiO₂) film with TiO₂ powder. Film was fabricated by electrochemical potentiostatic anodization of titanium thin film in an ethylene-glycol electrolyte solution containing 0.3 wt% NH₄F and 2 vol% deionized water. Nanotubes with a pore size of 80-100 nm were formed by anodization at 60 V for 3 h. Humic acid (HA) was degraded through photocatalytic degradation using the ntTiO₂ film. Pseudo first-order rate constants for 0.3 g of ntTiO₂, 0.3 g TiO₂ powder, and 1 g TiO₂ powder were 0.081 min⁻¹, 0.003 min⁻¹, and 0.044 min⁻¹, respectively. HA adsorption on the ntTiO₂ film was minimal while adsorption on the TiO₂ powder was about 20% based on thermogravimetric analysis. Approximately five-fold more normalized OH radicals were generated by the ntTiO₂ film than the TiO₂ powder. These quantitative findings explain why ntTiO₂ film showed superior photocatalytic performance to TiO₂ powder.

• Journal of the Korean Magnetics Society
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• v.8 no.6
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• pp.369-373
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• 1998

The exchange anisotropy between NiO antiferromagnetic layer and NiFe ferromagnetic layer has been investigated in NiFe(10 nm)/NiO(60 nm) formed by magnetron sputtering. The NiO films were sputtered from nickel oxide using R. F. poser and NiFe, Ta were deposited using D. C. power under Ar atmosphere. Above all. we studied the exchange anisotropy of Ni-Fe/NiO bilayer, and focused especially on the effect of NiO depostion condition. Our experimental data showed that the dominant factor for determining the exchange anisotropy properties was the Ar pressure during NiO deposition. The better exchange anisotropy properties were found when the NiO film was deposited at low Ar pressure probably due to the flatten interface and the epitaxial tendency of NiO grains and NiFe grains. However, as Ar pressure increased, interfacial diffusion at NiFe/NiO interface and oxygen content of NiO film increase, and consequently reduced the exchange anisotropy. We concluded that the flatten interface and relatively low oxygen content of NiO layer are dominant factors for the enhancement of the exchange anisotropy in NiFe/NiO bilayer.

• Proceedings of the Korean Magnestics Society Conference
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• 2012.05a
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• pp.121-122
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• 2012

Iron-excess gallium ferrite, $Ga_{0.6}Fe_{1.4}O_3$ (GFO), is known to have room-temperature ferromagnetic phases and potentially exhibit ferroelectricity as well [1]. But, leaky polarization-electric field (PE) hysteresis curves of the GFO thin film are hurdle to prove its spontaneous polarization, in other words, ferroelecticity. One of the reasons that the GFO films have leaky PE hysteresis loop is carrier hopping between $Fe^{2+}$ and $Fe^{3+}$ sites due to oxygen deficiency. We focus on reducing conducting current by substituting divalent cations at $Fe^{2+}$ sites. GFO thin films were grown epitaxially along b-axis normal to $SrRuO_3/SrTiO_3$ (111) substrates by pulsed laser deposition. Current density of the ion-substituted GFO thin films was reduced by $10^3$ or more. Ferroelectric properties of the ion-substituted GFO thin films were measured using macroscopic and microscopic schemes. In particular, local ferroelectric properties of the GFO thin films were exhibited and their remnant polarization and piezoelectric d33 coefficient were obtained.

• Journal of Preventive Medicine and Public Health
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• v.28 no.3 s.51
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• pp.663-677
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• 1995

Special health examination institute has done periodic health examination for workers who have worked in the hazardous workplace. However, assessment on outcome in special health examination institute about detection ability of occupational disease has not been. In this circumstances, we studied on the differences of health examination outcome among special health examination institutes and identified related factors which affected outcome of special health examination in the special health examination institutes. The summary of the results were as follows. 1. 50 special health examination institutes were examined in this study. Among them, university institutes were 13 cases(26.0%), hospitals were 20 cases(40.0%), a corporation aggregates were 9 cases(18.0%) and an auxiliary organs of company were 8 cases(16.0%). There were 29(58.0%) institutes with a preventive medicine specialist, but 21 institutes(42.0%) were not. 2. Total workers examined in 50 institutes were 606,948 and workers diagnosed as occupational disease$(D_1)$ were 3,156. The rate of occupational disease was 6 workers per 1,000 examined workers. Workers needed for close observation(C) were 95,809 and the rate of workers needed for close observation was 141 per 1,000 examined workers. 3. The rate of occupational disease of university institutes was highest(11.3 per 1,000 examined workers), and followed by hospitals(6.0 per 1,000 examined workers), a corporation aggregates(4.2 per 1,000 examined workers), and an auxiliary organs of company(1.2 per 1,000 examined workers). The difference of the rate of occupational disease between university institutes and an auxiliary organs of company was statistically moderate significant(p<.1). The rate of occupational disease in special health examination institutes with establishment duration was more than 10 years was statistically higher than institutes with establishment duration was less than 10 years(p<.1). 4. The results of multiple regression, $R^2$ was 0.3394(adjusted $R^2$ was 0.2109), F-value was 2.6416(p<.05), and statistically significant variables were establishment duration(p<.01), number of examined workers per one doctor(p<.1), and auxiliary organs of company(p<.1), which dependent variable was the rate of occupational disease and independent variables were number of examined workers per one doctor, classification of institute, the rate of working environment exceeding TLV, duration of institute establishment, presence of a preventive medicine specialist.

• Women's Health Nursing
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• v.8 no.2
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• pp.232-243
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• 2002

The purpose of this study was to examine factors influencing the meaning of life for middle-aged women. The subjects for the study were 190 middle-aged women who live in Busan. Data were collected from May 25 to June 20, 1999. The instruments for this study were as follows : the meaning of life scale developed by Jung D. R(1978) ; the self-esteem scale developed by Ro, E. Y, Kwon, J. H.(1997) ; the volunteer activity scale developed by Park G. J.(1999), the marital satisfaction scale developed by Choi G. Y.(1999) ; and the health status scale developed by Kim S. Y. (1991). SPSS PC+ was utilized for data analysis. Data were analysed according to frequency and percentage, mean and standard deviation, t-test, ANOVA, Sheffe' s test and Pearson' s correlation coefficients and stepwise multiple regression. The reliability of the tools was tested by Cronbach's $\alpha$ : and it showed reliability scores of 0.88(for the meaning of life tool), 0.81(for the self-esteem tool), 0.94(for the marital satisfaction tool) and 0.78(for the health status tool). The results were as follows: 1) The scores showed that middle-aged women had a moderate level of meaning of life, with a mean of 30.31 and standard deviation of 6.24 (with values ranging from 12.00 to 48.00). The scores showed that middle-aged women had a moderate levels of self-esteem, with a mean of 28.92 and standard deviation of 4.67 (with values ranging from 10.00 to 40.00). The scores showed that middle-aged women had a very low level of volunteer activity, with a mean of 0.87 and standard deviation of 0.93(with values ranging from 0.00 to 1.00). The scores showed that middle-aged women had a moderate level of satisfaction in their marriages, with a mean of 31.99 and standard deviation of 7.84(with values ranging from 12.00 to 48.00). The scores showed that middle-aged women had a moderate level of health status, with a mean of 6.63 and standard deviation of 1.57(with values ranging from 3.00 to 9.00). 2) There was a statistically significant difference of the meaning of life of middle-aged women according to their religion(F=8.930, p=.000), christian ($31.94{\pm}5.96$) had more meaning th life than buddhists ($28.40{\pm}6.23$). 3) There was a statistically significant correlations between the subject' s self-esteem and the her meaning of life(r=0.477, p=0.000), the subject' s level of volunteer activity and meaning of life(r=.428, p=.000), her level of marital satisfaction and meaning of life(r=.417, p=.000), and her level of health status and meaning of life(r=.261, p=.000) among these middle-aged women. 4) Self- esteem was the highest factor influencing the level of meaning of life in middle-aged women. 40.0% of the total variance of levels of meaning of life by was dependent on self-esteem, volunteer activity, marital satisfaction and health status. In conclusion, the higher the self-esteem and levels of volunteer activity, marital satisfaction, and health status of middle-aged women, the higher the meaning of life for them. Therefore, it is necessary to elevate levels of the self-esteem and volunteer activity, marital satisfaction and health status in order to help middle-aged women have more meaning of life.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.1
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• pp.37-49
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• 2015

During pregnancy, the maternal body undergoes significant physiological changes. The present study assessed the changes on calcium (Ca), phosphorus (P), magnesium (Mg), sodium (Na) and potassium (K) metabolism in singleton and twin-pregnant dairy goats. The 42 goats used ($49.5kg{\pm}7.6$ body weight [BW]) were assigned at random to treatments that were factorially arranged to account for 2 breeds (Oberhasli and Saanen), 2 pregnancy types (singleton and twin) and 3 gestation periods (80, 110, and 140 days). Digestibility trials were performed at 80, 110, and 140 days of gestation. Mineral retention during pregnancy was determined in the maternal body, femur, uterus, mammary gland, fetus and fetal fluid. Blood samples were taken during pregnancy before and after a meal, and Ca, P, Mg, Na, K ions and alkaline phosphatase activity determined in serum. Bone mineral density was determined in the right femur. Statistical analyses were performed using the SAS MIXED procedure. Dry matter intake decreased linearly up to 140 days of gestation. Maternal BW gain, and Ca, P, and Mg retention (g/kg) decreased linearly with the advance of gestation days. Macromineral retention in maternal body (g/kg) was greater in Oberhasli than Saanen goats, and their fetuses had higher Ca, P, and Mg deposition (mg/g). Mineral retention (mg/g) increased in fetuses according to pregnancy development, with no differences between singleton and twin pregnancy. In the mammary gland, the retention of all minerals (g) increased with the days of pregnancy. In conclusion, related to Ca, P, and Mg metabolism can be divided into two stages. Up to 80 days of gestation, was characterized by the preparation of the maternal body reserves for future mineral demands. From 80 days of gestation onward, was characterized by the transfer of maternal body reserves for fetal development and colostrum production. Na and K supply was provided by adjustments in endogenous excretion and an increase in intestinal absorption. Finally, mineral metabolism was specific to each genotype and, except for Na, was not affected by the number of fetuses.