• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.11a
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• pp.321-324
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• 2003

The effects of various sintering additives such as $Bi_2O_3+V_2O_5$, $BiVO_4$, $B_2O_3$, and $CuO+V_2O_5$ on the low-temperature sintering and microwave dielectric properties of $(ZnMg)TiO_3$ system were studied. Sintering was enhanced by the sintering additives and highly dense samples were obtained for $(Zn_{0.8}Mg_{0.2})TiO_3$ at the sintering temperature of $910^{\circ}C$. $(Zn_{0.8}Mg_{0.2})TiO_3$ with 6.19 mol.%$B_2O_3$ was found to show the best sintering and microwave dielectric properties.

• Journal of Plant Biotechnology
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• v.5 no.3
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• pp.181-185
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• 2003

Callus and suspension cultures derived from leaf explants of Plumbago rosea were established on Murashige and Skoog's medium containing 1 mg/L IAA, 0.5 mg/L NAA and 0.3 mg/L BAP. Callus cultures were tested for their growth and accumulation of plumbagin, a naphthoquinone and was identified by $^1H$ NMR and electron ionization mass spectroscopy. While auxins (not 2,4-D) influenced growth and plumbagin accumulation, cytokinins did not influence them much. Increasing concentrations of IAA in presence of NAA and BAP increased plumbagin in suspensions only up to 1 mg/L. Growth of callus was optimum (8.3 g DCW/I) at a hormonal combination of 1.5 mg/L IAA, 0.5 mg/L NAA and 0.3 mg/L BAP, but high plumbagin accumulation (4.9 mg/g DCW) was recorded at 1.0 mg/L IAA plus 0.3 mg/L BAP. Since instability in growth and secondary metabolite accumulation was noticed, several cell lines/clumps of callus were screened for plumbagin accumulation by visual and analytical methods. Biomass and accumulation of plumbagin showed a negative correlation in several cell lines. But one cell line showed stability both in terms of biomass and plumbagin accumulation over a period of 6 months.

• Journal of Preventive Medicine and Public Health
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• v.14 no.1
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• pp.97-110
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• 1981

This study was conducted in order to investigate the status of harmful working environ ment on twelve rubber and ten chemical products manufacturing industries in Busan area over a period of five months from lune 1 to October 31, 1980. The summarized results were as follows: 1. The highest and lowest mean values of harmful environmental elements in workroom of rubber products manufacturing industries were noted in twisting (98.7dB) and coating department (77.3dB) to noise, molding ($6.43mg/m^3$) and forming ($1.33mg/m^3$) to dust, bonding (toluene 463.7ppm, xylene 457.8ppm and benzene 111.8ppm, respectively) and splicing (toluene 90.0ppm, xylene 83.3ppm and benzene 6.7ppm, respectively) to organic solvents, respectively. Also in chemical products manufacturing, they were noted in grinding (95.1dB) and shining department (76.8dB) to noise, packing ($4.30mg/m^3$) and staining ($3.20mg/m^3$) to dust, shining (393.3ppm and 375.0ppm, respectively) and varnishing(125.5ppm and 121.7ppm, respectively) to toluene and xylene, and scattering (51.8ppm) and mixing (23.9ppm) to benzene, respectively. 2. The mean values of harmful elements in workroom of rubber products manufacturing were 86.3dB to noise, $4.16mg/m^3$ to dust, 258.2ppm to toluene, 230.3ppm to xylene, and 5 4.0ppm to benzene, respectively. Also in chemical products manufacturing, they were 85.2dB to noise, $3.69mg/m^3$ to dust, 227.9ppm to toluene, 213.2ppm to xylene, and 36.3ppm to benzene, respectively. 3. Number of workers exposed to harmful working environment, over TLV, of a total 10,195 workers in rubber products manufacturing were 1,002(9.8%) to noise, 212 (2.1%) to dust, 1,581(15.5%) to toluene, 1,509(14,8%) to xylene, and 1,524(15.0%) to benzene, respectively. Number of workers exposed to harmful working environment, over TLV, of a 1,913 workers in chemical products manufacturing were 112(5.9%) to noise, 132(6.9%) to each organic solvent, respectively. 4. The values of noise and dust of rubber and chemical products manufacturing in 1980 were lower then those in 1977, but the value of organic solvent in 1980 was similar with that in 1977.

• Journal of Physiology & Pathology in Korean Medicine
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• v.23 no.3
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• pp.590-598
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• 2009

The purpose of this research is to evaluate the effect of Mahaenggamseok-tang-gagambang (MGTG) on airway hyper- responsiveness (AHR), immune cells, cytokines and lung tissue in OVA-induced asthmatic mice. C578L/6 mice were injected, inhaled and sprayed with OVA for 12 weeks (3times a week) for asthma sensitization and challenge. Two experimental groups were treated with different concentrations of MGTG (400 mg/kg and 200 mg/kg) extract and cyclosporin A (10 mg/kg) for the later 8 weeks. Enhanced pause (Penh) levels were measured by whole body plethysmography. Immune cells were analyzed by flow cytometer in peripheral blood monocyte cell (PBMC) and lung cells. The IL-1b, IL-12, IFN-${\gamma}$, OVA-lgE, IL-4, IL-5, TNF-${\alpha}$ were analyzed by ELISA kit in serum and splenocyte+a-cCDS/a-CD28. Enhanced pause (Penh) levels of the MGTG groups (400 mg/kg and 200 mg/kg) were decreased significantly compared with that of control group. The numbers of MGTG groups (400 mg/kg and 200 mg/kg) on lung total cells were decreased significantly compared with that of control group. The numbers of MGTG groups (400 mg/kg and 200 mg/kg) on $CD3^+/CD69^+$, $B220^+/CD22^+$, $B220^+/CD23^+$, $B220^+/lgE^+$, $CCR3^+$ cells were decreased significantly compared with that of control group. The number of MGTG group (400 mg/kg) on $CD3^+/CD49b^+$ cells was decreased significantly compared with that of control group. The level of MGTG groups (400 mg/kg and 200 mg/kg) on IL-4, IL-5, IL-12, TNF-${\alpha}$, OVA-lgE were decreased significantly compared with that of control group. The level of MGTG group (400 mg/kg) on IL-1b, IL-1S, OVA-lgE were decreased significantly compared with that of control group. These results demonstrate that MGTG could be a desirable alternative therapy for allergic asthma by inhibiting the expression of immune cells, the activation of inflammatory mediator.

• Journal of Nutrition and Health
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• v.36 no.6
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• pp.646-652
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• 2003

This study was performed to determine the iron status of the adolescent Korean girls before and after menarche. The 101 subjects aged 11-13 years who attending in an elementary school in Mokpo were recruited. They were divided into pre-menarche (A) group or post-menarche (B) group based on their menstruation status. The latter subjects were sub-divided into one of the four groups according to the times of their menstruation B-I( $\geq$ 3 times), B-II (4-6 times), B-III (7-9 times) or B-W ( $\geq$ 10 times). In the total subjects, dietary iron intake, 11.3 mg/day, was below the Korean RDA for iron, the percentage of heme iron to total iron intake, 15%, and the bioavailability of dietary iron, 12.3%, seemed to be low. And their body iron storage, 140.8 mg, seemed to be insufficient. However, they tended to meet body's iron requirement in the cell level. Red blood cell number (RBC), hematocrit (Hct), and hemoglobin (Hb) level in the total subjects were 4.5 1012/I, 39.3%, and 13.0 g/㎗, respectively. The subjects in B group had lower (p<0.05) RBC and Hct compared to those in A group and the prevalence of iron-deficiency anemia tended to be high. Serum iron, ferritin, and soluble transferrin receptor (sTfR) and sTfR:ferritin ratio were 86.7 $\mu\textrm{g}$/d, 17.6 $\mu\textrm{g}$/l, 3.58 mg/1, and 230, respectively. Those four indices were not significantly different among the groups. The results of this study imply that, although there a tendency to affect negatively iron status, menstrual blood loss in adolescent females does not deteriorate obviously their iron status during the relatively short period up to 1 you. However, it should be better to improve their iron status after starting menarche by increasing iron intake, especially heme-iron, and enhancing factors for iron absorption.

• Food Science and Preservation
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• v.6 no.4
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• pp.463-468
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• 1999

The characteristics and quality of Yakju with addition of ginseng powder originated in Choongchungdo were evaluated. At result, pH was decreased at the beginning stage of two stages fermentation and then slowly increased. Total acidity were increased in the cases of all (A), (B) and (C) during the fermentation. (A) group used Nuruk, crude enzyme and powder yeast showed the highest pH of 7.08 and total acidity of 0.84 at the 4th day of fermentation. The alcohol contents of B(21.0%) and C(20.4%) used cultured yeast were higher than A(19.0%) used powder yeast at the 4th day of fermentation. Also, inhibition against alcohol fermentation by ginseng powder wasn't showed and amino nitrogen contents were higher in (A) and (C) with addition of crude enzyme. Free sugar were the highest in (A) used both Nuruk and crude enzyme such as glucose of 599.16, maltose of 129.11mg%. Free amino acids were much more in A(580.02mg%) than in B(527.48mg%) and C(538.74mg%). from the sensory evaluation, desirable color and flavor qulity for 40 ages was (A) and (B) which was used Nuruk, and that for 20 ages was (C) which was used crude enzyme. However the best taste and overall preference was (B) for 20 and 40 ages of all. Therefore to produce high quality Yauju and commercialize, studies of fermentation process in Yakju should proceed later.

• Korean Chemical Engineering Research
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• v.59 no.4
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• pp.611-625
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• 2021

Mg crowns were manufactured using domestic dolomite (Ca·Mg(CO₃)₂) (20~30 mm). In order to manufacture the calcined dolomite (CaO·MgO), (a) electric furnace (950 ℃, 480 min) and (b) microwave furnace (950 ℃, 60 min) processes were used. As a result of XRD analysis, it was analyzed as (a) CaO 56.9 wt%, MgO 43.1 wt% by electric furnace process and (b) CaO 55 wt%, MgO 45 wt% by microwave furnace process. Even when the decarbonation reaction time of dolomite was shortened by 1/8 in microwave furnace process compare with electric furnace process, the calcined dolomite could be produced. The hydration reaction (ASTM C 110) is a standard for the hydration reactivity of calcined dolomite, and the calcined dolomite produced by electric furnace process showed a high hydration reactivity (max temp 79.8 ℃/1.5 minutes). Such hydration reactivity was occurred by only CaO hydration reaction and that was confirmed by XRD analysis. The calcined dolomite produced by microwave furnace process showed low hydration reactivity (max temp 81.7 ℃/19.5 minutes). Such low hydration reactivity was occurred by CaO and MgO hydration reaction due to the hydration reaction of CaO thereafter occurring of the hydration reaction of MgO, and that was confirmed by XRD analysis. The prepared Mg crown were 58.8 g and 74.6 g by electric furnace and microwave furnace processes, respectively, under the reaction conditions of 1,230 ℃, 60 min, 5 × 10^-2 torr by silicothermic reduction.

• Journal of Veterinary Clinics
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• v.7 no.2
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• pp.511-515
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• 1990

Induction of twinning was attempted by transfer of two whole- or demi-embryos in Holstein cows and heifers. Cows were superovulated with follicle stimulating hormone(FSH) administered twice daily in intra-muscular injection. On day of 6.5 to 7 post-estrus, embryos were collected nonsurgically, Normal morulae and early balstocysts were obtained from superovulated cows. The embryos were hisected with a micro-blade made from a razor. Twenty seven pairs of half embryos were successfully produced and 23 pairs of half embryos were transferred to recipients( Group A). Twenty cows were treated with low unit of FSH (3mg${\times}$2,2mg${\times}$2 ; Group B1, 2mg${\times}$2, 1mg${\times}$2, 1mg${\times}$2 ; Group 32) to induce double or triple ovulations. The cows of Group B1 and B2 were Inseminated artificially(A1) at following estrus. Twenty four heifers were bred by A1 and received an additional embryo into the uterine horn contralateral to the corpus luteum(CL) 6 days later(Group C). One embryo was transferred into each uterine hem of 16 heifers 6 days after estrus(Group D). Fourteen heifers were received two embryos into the uterine horn ipsilateral to the CL at day 6 of estrous cycle(Group I). Pregnancy rates at 60 days in Group A, B1, B2, C, D and E were 34.8％, 70.0％, 60.0％, 66.7％, 62.5％ and 57.1％, respectively. Twinning rates were 8.7％, 20.0%, 10.0％, 16.7％, 18.7％ and 21.4％, respectively. The present experiments demonstrate that FSH treatment( Group 31) and ipsilateral transfer( Group I ) of two whole-embryos are more useful methods to produce twins than the others.

• Journal of the Korean Magnetics Society
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• v.17 no.4
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• pp.162-165
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• 2007

We investigated the effects of the capping layer materials on the crystallization of the amorphous top-CoFeB (t-CoFeB) electrode and the magnetoresistance properties of the magnetic tunnel junctions (MTJs). When the hcp(002)-textured Ru capping layer was used, the amorphous t-CoFeB was crystallized to bcc-CoFe(110). The CoFe(110)/Ru(002) texture relation can be minimized the lattice mismatch down to 5.6%. However, when the fine polycrystalline but almost amorphous TiAl or amorphous ZrAl were used, the amorphous t-CoFeB was crystallized to bcc-CoFe(002). When the amorphous capping materials were used, the evolution of the t-CoFeB texture was affected mainly by the MgO(001) texture. Consequently, the M ratios of the annealed MTJ capped with the ZrAl and TiAl (72.7 and 71.8%) are relatively higher than that of the MTJ with Ru capping layer (46.7%). In conclusions, the texture evolution of the amorphous t-CoFeB during the post deposition annealing could be controlled by the crystallinity of the adjacent capping layer and in turn, it affects the TMR ratio of MTJs.

• Journal of environmental and Sanitary engineering
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• v.18 no.2
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• pp.1-8
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• 2003

The advantages of hydrogen peroxide dissolution method were no discharge of noxious matter when dissolution of molybdenum wire which used as the center supporter, reactions occur in room temperature. The results were as follows : 1. In the FL/10-A type: Dissolution-reaction Time was 50Min., C.R.(Coil resistance) was $9.27{\Omega}(St.{\;}:{\;}9.2{\pm}0.22{\Omega})$, P.W.(Piece weight) was $10.59mg(St.{\;}:{\;}10.5{\pm}0.26mg)$. In the FL/15-D type: Dissolution-reaction Time was 55Min., C.R. was $6.39{\Omega}(St.{\;}:{\;}6.38{\pm}0.02{\Omega})$, P.W. was $16.7mg(St.{\;}:{\;}16.5{\pm}0.3mg)$. In the FL/20-H type: Dissolution-reaction Time was 45Min., C.R. was $4.7{\Omega}(St.{\;}:{\;}4.6{\pm}0.3{\Omega})$, P.W. was $20.8mg(St.{\;}:{\;}20{\pm}1.5mg)$. In the FL/20-C type: Dissolution-reaction Time was 60Min., C.R. was $4.5{\Omega}(St.{\;}:{\;}4.6{\pm}0.3{\Omega})$, P.W. was $19.8mg(St.{\;}:{\;}19{\pm}1.0mg)$. 2. In the GLS-230/40-B type: Dissolutiona-reaction Time was 45Min., C.R. was $105.1{\Omega}(St.{\;}:{\;}104{\pm}2.6{\Omega})$, P.W was $6.37mg(St.{\;}:{\;}6.3{\pm}0.16mg)$. In the GLS-230/60-F type: Dissolution- reaction Time was 45Min., C.R. was $65.92{\Omega}(St.{\;}:{\;}65{\pm}1.62{\Omega})$, P.W. was $11.91mg(St.{\;}:{\;}11.8{\pm}0.29mg)$.