• 한국신재생에너지학회:학술대회논문집
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• 2007.06a
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• pp.196-199
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• 2007

The chemical states of oxygen on the surfaces of $Pr_{1-x}Sr_{x}CoO_{3}$ (x=0.5 and 0.7) oxide systems were investigated by X-ray photoelectron spectroscopy. Merged oxygen peaks of $Pr_{1-x}Sr_{x}CoO_{3}$ (x=0.5 and 0.7) oxides could be divided as five sub-peaks. These five sub-peaks could be defined as lattice oxygen ($O_{L}$). chemisorbed oxygen peaks ($O_{C}$) and hydroxyl condition oxygen peak ($O_{H}$). In case of the $Pr_{0.5}Sr_{0.5}CoO_{3}$ and $Pr_{0.3}Sr_{0.7}CoO_{3}$, the binding energy (BE) of oxygen lattice were located at same BE. However, the BE of chemisorbed oxygen peaks including oxygen vacancy shows different BE. Especially, it was found that BE of chemisorbed oxygen peaks was increased when more Sr were substituted. Comparing atomic percentages of oxygens of $Pr_{0.5}Sr_{0.5}CoO_{3}$ and $Pr_{0.3}Sr_{0.7}CoO_{3}$, the ratio of $Pr_{0.3}Sr_{0.7}CoO_{3}$ was higher than that of $Pr_{0.5}Sr_{0.5}CoO_{3}$. It showed more chemically adsorbed site including oxygen vacancies were existed in $Pr_{0.3}Sr_{0.7}CoO_{3}$.

• Applied Biological Chemistry
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• v.47 no.4
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• pp.379-383
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• 2004

For the elucidation of substrate specificity to the brown copra meal by Bacillus sp. ${\beta}-mannanase.$, the enzymatic hydrolysate after 24 hr of reaction was heated in a boiling water bath for 10 min, and then centrifuged to remove the insoluble materials from hydrolysates. The major hydrolysates composed of D.P 5 and 7 galactosyl mannooligosaccharides. For the separate of galactosyl mannooligosaccharides, the supernatant solution of 150 ml was put on a first activated carbon column. The column was then washed with 5 l of water to remove mannose and salts. The oligosaccharides in the column were eluted by a liner gradient of $0{\sim}30%$ ethanol, at the flow rate of 250 ml per hour. The sugar composition in each fraction tubes was examined by TLC and FACE analysis. The combined fraction from F3 was concentrated to 30 ml by vacuum evaporator. Then put on a second activated carbon column. The oligosaccharides in the column were eluted by a liner gradient of $0{\sim}30%$ ethanol (total volume: 5 l), at the flow rate of 250 ml per hour. The eluent was collected in 8 ml fraction tubes, and the total sugar concentration was measured by method of phenol-sulfuric acid. The major component of F2 separated by 2nd activated carbon column chromatography were identified $Gal^3Man_4(6^3-mono-{\alpha}-D-galactopyranosyl-{\beta}-mannotetraose)$. To investigate the effects of brown copra meal galactomannooligosaccharides on growth of Bifidobacterium longum, B. bifidum were cultivated individually on the modified-MRS medium containing carbon source such as $Gal^3Man_4$, compared to those of standard MRS medium.

• Economic and Environmental Geology
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• v.27 no.2
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• pp.171-180
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• 1994

Several ultramafic bodies and ultramafic origin talc deposits are distributed in Chungnam province near the contact zone with Ogchun fold belt They occur as discontinued belt form with northeast trending, and most of them are more or less sepentinized. Major, trace, and rare earth elements analyses were made of the ultramafics from the study area to constrain their origin and genetic relationships. Compared to the primitive mantle estimates of privious workers, the correlations defined by the studied rock samples indicate similar Ni but very lower $Al_{2}O_{3}$, CaO and $TiO_{2}$ contents. It is inferred that source material of the studied rocks might be residual mantle which had undergone a large degree of partial melting event. The REE patterns show relatively flat to enriched in LREE (chondrite normalized La/Yb and Sm/Yb ratios are 1.1-5.2 and 1.2-1.6). Several alternative explaination are possible for LREE enrichment patterns in the studied ultramafic rocks such as 1) enrichment due to late stage alteration, 2) enriched pre-melting composition, and 3) mixing of two components. Based on the result, the LREE enrichment characteristic of the studied rocks might be result from the mixture of two geochemically distinct components; one is depleted residual mantle and the other component which determine the abundances of incompatible elements and responsible for the LREE enrichment.

• Journal of Animal Science and Technology
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• v.51 no.1
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• pp.25-32
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• 2009

This study was conducted to determine the effects of probiotics supplementation on growth performance, nutrient digestibility, occurrence of diarrhea and immune response in weaning pigs. Treatments were 1) NC (basal diet), 2) PC (basal diet + 0.12% avilamycin) and 3) A (basal diet + 0.2% Aspergillus oryzae), 4) B (basal diet + 0.2% Lactobacillus casei), 5) C (basal diet + 0.2% Bacillus subtilis), 6) D (basal diet + 0.2% Lactobacillus crispatus). A total of 120 pigs ($7.16\pm0.01$ kg average body weight, weaned at $23\pm3$days of age) were assigned to 6 treatments, 5 replicates and 4 pigs per pen in a randomized complete block (RCB) design. During the whole experimental period, body weight (P<0.01), average daily gain (ADG; P<0.01), and average daily feed intake (ADFI; P<0.05) of treatment PC were higher than other treatments. However, the probiotics treatments tended to increase ADG and G:F ratio compared to treatment NC. The G:F ratio in treatment A (Aspergillus oryzae) was similar to treatment PC during the whole experimental period (P<0.05). The supplementation of probiotics in the diet of weaning pig did not change nutrient digestibility (dry matter, crude protein, crude fat and ash) and nitrogen retention of weaning pigs. In blood urea nitrogen (BUN) concentration, treatment B had lower value than other treatments at 2 and 4 weeks (P<0.05). Treatments PC and C tended to decrease diarrhea score than other treatments (P=0.18). At 3h after lipopolysaccharide (LPS) injection, treatments NC and PC had higher count of $CD^{4+}$ T-cells than probiotics treatments, and treatment C showed the lowest value (P<0.01). There were no differences on count of $CD^{8+}$ T-cells and $CD^{4+}:CD^{8+}$ ratio among all treatments (P>0.10). These results suggest that the dietary probiotics are likely able to improve the growth performance, occurrence of diarrhea and immune response although they do not have similar effects like antibiotics in weaning pigs.

• Journal of The Korean Society of Grassland and Forage Science
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• v.5 no.2
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• pp.121-126
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• 1985

Phytotron and field experiments were conducted to determine the influence of morphological growth stage and environmental temperature on synthesis and accumulation pattern of cyanogenic glycosides in sorghum cv. Pioneer 931 and Sioux at Munich technical university from 1979 to 1980. Various growth stages of sorghum plants were grown in phytotron at 4 different temperature regimes of 30/25, 25/20, 28/18 and 18/8 degree C with 35,000 Lux over 13-h days. The results obtained are summarized as follows: 1. Cyanogenic glycosides in sorghum plants were shown to have a great synthetic rate at early growth stages. The highest concentrations of hydrocyanic acid (HCN) were found at 2-leaf stage with 2384 and 1800ppm (DM basis) for Pioneer 931 and Sioux respectively. The contents of HCN were, however, however decreased markedly as morphological development, which shows a value of 173ppm (Pioneer 931) and 70ppm (Sioux) at heading stages. 2. Changes of hydrocyanic acid in sorghum plants were positive correlated with leaf weight ratio and leaf area ratio ($P{\leqq}0.1%$), while plant height shows a negative correlation with HCN contents ($P{\leqq}0.1%$). 3. Cyanogenic glycosides were accumulated in young plants mainly in leaves. During the late maturities, the contents of HCN in leaves and stalks were shown, however, a similar distribution. 4. Synthesis rates of cyanogenic glycosides were increased under high temperature. Accumulated hydrocyanic acid in the plants was, however declined when temperature exceeded 30 degree C. 5. Synthesis rates of cyanogenic glycosides were affected by nitrogen reductase activity (NRA). The concentration of hydrocyanic acid in sorghum plants was associated with increasing of nitrate-N accumulation.

• Journal of Technologic Dentistry
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• v.20 no.1
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• pp.37-49
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• 1998

The specimens used were Ag-25 Pd-15 Cu ternary alloy and Au addition alloy. These alloys were melted and casted by induction electric furnace and centrifugal casting machine in Ar atmosphere. These specimens were solution treated for 2hr at $800^{\circ}C$ and were then quenched into iced water, and aged at $350{\sim}550^{\circ}C$ Age- hardening characteristics of the small Au-containing Ag-Pd-Cu dental alloys were investigated by means of hardness testing. X-ray diffraction and electron microscope observations, electrical resistance, ergy dispersed spectra and electron probe microanalysis. Principal results are as follows : Hardening occured in two stages, i.e., stage I in low temperature and stage II in high temperature regions, during continuous aging. The case of hardening in stage I was due to the formation of the $L1_0$ type face-centered tetragonal PdCu-ordered phase in the grain interior and hardening in stage I was affected by the Cu concentration. In stage II, decomposition of the ${\alpha}$ solid solution to a PdCu ordered phase($L1_0$ type) and an Ag-rich ${\alpha}2$ phase occurred and a discontinuous precipitation occurred at the grain boundary. From the electron microscope study, it was conclued that the cause of age-hardening in this alloy is the precipitation of the PdCu ordered phase, which has AuCu I type face-centered tetragonal structure. Precipetation procedure was ${\alpha}{\to}{\alpha}+{\alpha}_2+PdCu {\to}{\alpha}_1+{\alpha}_2+PdCu$ at Pd/Cu = 1.7 Ag-Pd-Cu alloy is more effective dental alloy as ageing treatment and is suitable to isothermal ageing at $450^{\circ}C$.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.10 no.3
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• pp.189-198
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• 2000

The stochiometric mixture of evaporating materials for the $CuGaSe_2$single crystal thin films were prepared from horizontal furnace. Using extrapolation method of X-ray diffraction patterns for the polycrystal $CuGaSe_2$, it was found tetragonal structure whose lattice constant $a_0}$ and $c_0$ were 5.615 $\AA$ and 11.025 $\AA$, respectively. To obtains the single crystal thin films, $CuGaSe_2$mixed crystal was deposited on throughly etched GaAs(100) by the Hot Wall Epitaxy (HWE) system. The source and substrate temperature were $610^{\circ}C$ and $450^{\circ}C$ respectively, and the growth rate of the single crystal thin films was about 0.5$\mu\textrm{m}$/h. The crystalline structure of single crystal thin films was investigated by the double crystal X-ray diffraction (DCXD). Hall effect on this sample was measured by the method of van der Pauw and studied on carrier density and mobility depending on temperature. From Hall data, the mobility was likely to be decreased by pizoelectric scattering in the temperature range 30 K to 150 K and by polar optical scattering in the temperature range 150 K to 293 K. The optical energy gaps were found to be 1.68 eV for CuGaSe$_2$sing1e crystal thin films at room temperature. The temperature dependence of the photocurrent peak energy is well explained by the Varshni equation then the constants in the Varshni equation are given by $\alpha$ = $9.615{\times}10^{-4}$eV/K, and $\beta$ = 335 K. From the photocurrent spectra by illumination of polarized light of the $CuGaSe_2$single crystal thin films. We have found that values of spin orbit coupling $\Delta$So and crystal field splitting $\Delta$Cr was 0.0900 eV and 0.2498 eV, respectively. From the PL spectra at 20 K, the peaks corresponding to free bound excitons and D-A pair and a broad emission band due to SA is identified. The binding energy of the free excitons are determined to be 0.0626 eV and the dissipation energy of the acceptor-bound exciton and donor-bound exciton to be 0.0352 eV, 0.0932 eV, respectively.

• Journal of Animal Science and Technology
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• v.44 no.5
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• pp.531-540
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• 2002

This study was conducted to examine the effect of Hwangto, Illite, and any other disease resistant materials as dietary supplements on the growth performance and immunity for growing period with 30 Hanwoo male calves weaned 75days in age. Feeding trial was conducted with 6 treatments(five heads/treatment), which were T1(Control), T2(Control + 2% Hwangto), T3(Control + 2% Illite), T4(Control + 0.04% Oligosacharides), T5(Control + 2% Charcoal powder) and T6(Control + 0.1% Chromium picolinate) for 120 days from three to seven months in age. The results obtained are summarized as follows; During the experimental period, average daily gains were 0.82 to 0.92kg, and were high in the order of T3, T6, T4, T5, T2 and T1. Especially the growth rate of calves for growing period was higher in Illite, chromium-picolinate and oligo- sacharides feeding groups than in any other groups. Average daily intakes and intake ratio to body weight of concentrates for 120days were 3.91 to 4.15kg(average 4.03kg) and 3.10 to 3.31% (average 3.21%), respectively. TDN intakes per kilogram gains were 3.20 to 3.57kg(average 3.35kg) and were smaller in the order of T5, T3, T6, T4, T2 and T1, respectively. Density of IgG in serum of calves measured by the IgG SDID Kit was 10.2 to 11.6mg/$m\ell$, and especially increase rate of IgG for experimental period was high in T3 and T5 by 6.9 and 2.8%, respectively. But incidence of disease was not found to be different by treatments. According to the above results it may be concluded that Illite is a sort of clay minerals increased the growth rate, feed efficiency and immunity of early weaned calves for growing period, but was not in unprocessed Hwangto.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.9
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• pp.1384-1390
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• 2010

In this study, we investigated the quality of glasswort (Salicornia herbacea L.) mixture fermented by Aspergillus oryzae at $30^{\circ}C$ for 7 days. Changes of pH, titratable acidity, amino-nitrogen content, reducing sugar content, activities of $\alpha$-amylase and protease and number of mold were determined in the course of the fermentation. Angiotensin converting enzyme (ACE) inhibition activities and electron donating ability (EDA) were measured after 7 days fermentation. The pH lowered from 6.19~6.22 into the level of 5.41~6.08 after fermentation for 7 days. Titratable acidity increased from 0.59~0.68 into the highest level of 0.95~1.13% after 6 days fermentation. Furthermore, the amino-nitrogen content increased from 128.0~167.2 mg% to 159.4~209.0 mg% after fermentation for 7 days. For the reducing sugar content, it decreased from 2.0~5.9% into the level of 0.4~1.1% during 7 days fermentation. The number of molds decreased from $10^7\;CFU/g$ to approximately $10^6\;CFU/g$ after 5 days fermentation. $\alpha$-Amylase activity showed from the beginning of the fermentation in all samplings, but protease activity reached the value of food code standards after 5 days of fermentation. ACE inhibition activities were slightly increased from 9.5~16.6% to 19.3~22.7% and electron donating ability were slightly increased from 55.6~57.8% to 60.9~62.7% after 7 days of fermentation.

• Korean Journal of Environmental Agriculture
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• v.12 no.2
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• pp.144-152
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• 1993

A bacterium which degrades efficiently synthetic detergents was isolated from the polluted waters, activated sludge of wastewater treatment plants or polluted soil. This bacterium showed considerably higher growth rate in the agar plate containing $2,000{\mu}g/ml$ of synthetic detergents than any other isolated strains, was identified as a Pseudomonas fluorescens or strains similar to it. The strain was named as a Pseudomonas fluorescens S1. Optimum pH and temperature for the growth of the Pseudomonas fluorescens S1 were pH 7.0 and $30^{\circ}C$, respectively. The strain was resistant to streptomycin and gentamycin, but sensitive to kanamycin. The strain was greatly resistant to zinc chloride, lead nitrate and copper sulfate, but unable to grow in the presence of relatively low concentrations of mercury chloride and silver nitrate. This strain utilized benzene, catechol, cyclohexane and xylene as a sole carbon source. The strain was well grown in the medium containing ABS 10,000${\mu}g$/ml. Degradation of ABS was 55% and 60% at 20${\mu}g$/ml and 100${\mu}g$/ml of ABS, respectively. Benzene ring was degraded 45% in 100${\mu}g$/ml of ABS. During the incubation of the strain in the medium containing ABS 100${\mu}g$/ml and COD 10,000${\mu}g$/ml for 4 days, degradation of ABS and COD were reduced to 40${\mu}g$/ml and 3,200${\mu}g$/ml, respectively. Total amino acid content of the Pseudomonas fluorescens S1 grown with 1,000${\mu}g$/ml of ABS was 115mg/g cell, whereas its content was decreased in the bacterium grown without synthetic detergent by 9.4%.