• Journal of the Korean Vacuum Society
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• v.19 no.1
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• pp.36-44
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• 2010

The ambipolar diffusion equation has been solved in a fine-tube lamp of a few mm in diameter. In the diffusion of radial direction, the plasma diffuses and vanishes away at the glass wall by recombination with the characteristic time of plasma loss is given by $\tau_r\;=\;(r_0/2.4)^2/D_a$. With the radius $r_0{\sim}1\;mm$ and the ambipolar diffusion coefficient $D_a{\sim}0.01\;m^2/s$, the vanishing time is calculated $\tau_r{\sim}10\;{\mu}s$ which corresponds to the least value of frequency 30 kHz for the sustaining the plasma in the operation of high voltage AC-power. In the diffusion of longitudinal z-direction, a high density plasma generated at the area of a high voltage electrode, diffuses into the positive column with the characteristic time $\tau_z{\sim}0.1\;s$. The plasma diffusion velocity at the boundary of high density plasma is $u_D{\sim}10^2\;m/s$ at the time $t{\sim}10^{-6}$ s and the diffusion velocity becomes slow as $u_D{\sim}1\;m/s$ at $t{\sim}10^{-3}\;s$. Therefore, for the long lamp of 1 m, it takes about several seconds for the high density plasma at the area of electrode to diffuse through the whole positive column space.

• Journal of the Mineralogical Society of Korea
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• v.15 no.2
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• pp.85-94
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• 2002

XRF, XRD, EPMA have been used to investigate microstructures and mineralogical changes caused by the faulting and fluids associated with faulting in the Quaternary fault gouge zones at the Sangchon, Ipsil and Wangsan faults located at the southeastern part of the Korean Peninsula. The chemical compositions of faulted rocks and protoliths analyzed by XRF show that the fault gouges are relatively enriched in TiO$_2$, P$_2$O$_{5}$, MgO, and Fe$_2$O$_3$) compared with protoliths, indicating that the fluids associated with faulting were highly activated. XRD results show that the fault gouges predominantly consist of quartz, feldspar, calcite and clay minerals. Clay minerals formed in the gouge zones are mainly composed of smectite characterized by a dioctahedral sheet. Based on EPMA analyses various kinds of sulfide, carbonate, phosphate minerals were identified in the gouge zones and protoliths. Xenotime of grey fault gouge of the Sangchon fault and sulfide minerals of contact andesitic rock of Ipsil fault and contact grey andesitic rock of Wangsan fault were probably formed by inflow of hydrothermal solution associated with faulting prior to the Quaternary. Carbonate minerals of contact andesitic rock and gouge zone of the Ipsil fault were formed by inflow of fluid associated with faulting prior to the Quaternary. They are heavily fractured and have reaction rim on their edge, indicating that faultings and inflow of fluids were highly activated after carbonate minerals were formed. Calcites of Wangsan fault seemed to be formed in syntectonic or posttectonic Quaternary faulting.g.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.18 no.6
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• pp.529-537
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• 1985

The present study was carried out to investigate the effect of the partial freezing as a means of keeping freshness of mullet (Mugil cephlus). Living samples were killed and stored by icing, partial freezing at $-3^{\circ}C$ and freezing at $-30^{\circ}C$, respectively, Changes in the freshness of the mullet muscle and the phys cal properties of its meat paste product were examined during storage. The results obtained are summarized as follows: The period that k value reached to $20\%$ during storage was the longest in the frozen storage, followed by the partial frozen storage and the ice storage, which was 4 days in the mullet muscle stored by partial freezing. In the case of VBN content, it was below 20 mg/100g in the mullet muscle stored by icing and partial freezing. The oxidation of lipids in the mullet muscle was greater in the ice storage than in the partial frozen storage. The myofibrillar protein of the mullet muscle was appeared to decrease during storage, which the decreasing ratios during storage for 9 days were below $3\%$ in the frozen storage, $17\%$ in the ice storage and $10\%$ in the partial frozen storage. While, the alkali-soluble protein showed to increase and in non-protein nitrgenous compounds, sarcoplasmic protein and stroma was not a great change during storage. The decrease of gel strength, folding strength and texture of meat paste products prepared under different storage conditions was the greatest in the ice storage, the next in the partial frozen storage and such changes in the frozen storage were not so much. In gel strength of the product prepared with sample fishes stored for 10 days, the gel strength in the ice storage, partial frozen storage and frozen storage was about $30\%,\;60\%\;and\;97\%$ of the control. respectively. The expressible drip of the products increased with storage time of raw fishes, which that of the products prepared with sample fishes stored for 15 days was about 2.1 times in the ics storage, about 1.5 times in the partial frozen storage and about 1.1 times in frozen storage as much as that of the control, respectively.

• Analytical Science and Technology
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• v.15 no.5
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• pp.417-426
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• 2002

Inductively Coupled Plasma Dynamic Reaction Cell Quadrupole Mass Spectrometry (ICP-DRC-QMS) was characterized for the detection of the six naturally occurring calcium isotopes. The effect of the operating conditions of the DRC system was studied to get the best signal-to-noise ratio. This experiment shows that the potentially interfering ions such as $Ar^+$, ${CO_2}^+$, ${NO_2}^+$, $CNO^+$ at the calcium masses m/z 40, 42, 43, 44 and 48 were removed by flowing $NH_3$ gas at the rate of 0.7 mL/min $NH_3$ as reactive cell gas in the DRC with a RPq value (rejection parameter) of 0.6. The limits of detection for $^{40}Ca$, $^{42}Ca$, $^{43}Ca$, $^{44}Ca$, and $^{48}Ca$ were 1, 29, 169, 34, and 15 pg/mL, respectively. This method was applied to the determination of calcium in synthetic food digest samples (CCQM-P13) provided by LGC for international comparison. The isotope dilution method was used for the determination of calcium in the samples. The uncertainty evaluation was performed according to the ISO/GUM and EURACHEM guidelines. The determined mean concentration and its expanded uncertainty of calcium was ($66.4{\pm}1.2$) mg/kg. In order to assess our method, two reference samples, Riverine Water reference sample (NRCC SLRS-3) and Trace Elements in Water reference sample (NIST SRM 1643d), were analyzed.

• Journal of Animal Science and Technology
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• v.44 no.6
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• pp.769-782
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• 2002

Three kinds of green forages(rye, oats and mixed forages) was harvested and mixed with rice straw, wheat bran and 2 grains(corn and soybean), which harvested 2 different dates(common harvesting dates, 7 days early to common harvesting dates). And each mixture was ensiled in 6 poly vinyl chlorides that was 60 liter, immediately. They were opened at 0, 5, 10, 25, 35, 60 and 100 days after ensiling for chemical analysis. And its effects of those TMFFs on feed values were observed. Average contents of water, crude protein, ADF, NDF, Ca and P of formulated TMFs were 72 to 75%, 14.75 to 18.24, 12.47 to 19.07, 39.82 to 47.01, 0.99 to 1.07 and 0.38 to respectively. Crude protein content was the highest in the mixed forages-TMFF and the lowest in the rye-TMFF. The ADF and NDF contents of rye-TMFF were higher than orthers. And CP, ADF, NDF, TDN, P and Ca contents were no significant difference among treatments regardless of storage period and harvest time, but all treatments indicated good quality. Intenal temperatures of TMFF were shown to be 1 to 5$^{\circ}C$ higher than ambient temperatures. The temperature of the Oat-TMFF formulated during winter sustained higher to the level of 6${\sim}$9$^{\circ}C$ for 10 days. The pH of TMFF were 4.0 to 4.2 and the content of $NH_3$-N was shown to be 7.79 to 8.23mg/$d{\ell}$. In the VFA contents, any tendency was not shown at all treatments depending on harvest time. Even though rye-TMFF showed the lowest VFA value. At all treatments except rye-TMFF, propionate production was increased and stable after 25 days of storage. Digestibility of rice straw from TMFF on DM basis was 15${\sim}$20% higher compared with non-treated rice straw.

• Korean Journal of Poultry Science
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• v.32 no.3
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• pp.187-193
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• 2005

This study was carried out to investigate the effect of the bleeding times(30sec., 90sec., 150sec.) at slaughtering process on meat quality and storage properties of broiler. The redness$(a^{\ast}\;value)$ of skin, wing, leg muscle decreased at high bleeding time(150sec.). However, there was no significant difference in breast muscle. WHC(water holding capacity) of breast muscle decreased from $63.64\%$ at low bleeding time(30sec.) to $61.06\%$ at high bleeding time. TBARS(thiobarbituric acid-reactive substance) values were 0.18 mgMA/kg at the low bleeding time, 0.16 mgMA/kg at the middle bleeding time(90sec.) and 0.21mgMA/kg high bleeding time on 3 days of storage. Total aerobic plate counts(TPC) were $6.25logCFU/cm^2$ at the low bleeding time, $6.25logCFU/cm^2$ at the middle bleeding time and $6.53logCFU/cm^2$ at the high bleeding time. The TPC was increased as the bleeding time increased. In conclusion, meat color of chicken were acceptable when the carcasses were slaughtered at the high bleeding time.

• Journal of Preventive Medicine and Public Health
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• v.26 no.1 s.41
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• pp.110-125
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• 1993

This study was designed to determine whether non-violent criminal and normal control on the basis of concentration of levels of trace mineral and toxic metal by analysis of human scalp hair. The subjects were selected 87 nonviolent criminal from a prison population and 120 normal control from periodic health checks for study. Hair samples were taken from the napes and Minnesota Multiple Personality Inventory (MMPI) was performed also. Five trace mineral (Zn, Cu, Mg, Fe, Na) and two toxic metal (lead, cadmium) contents were determined by an atomic absorption spectrometer. The contents of zinc and magnesium in hair of non-violent criminal were significantly lower than the control group (p<0.01). In the case of lead and cadimum, mean value of criminal group was significantly higher than control group. Significantly higher T-score of MMPI was seen in non-violent criminal group fur psychopathic deviate (Pd), paranoia scale (Pa), and Mania scale (Ma) than control group, but T-score of depression scale (D) was significantly higher in the control group. In the non-violent criminal group, the content of copper inversely proportion to T-score of Hs, D, Hy, Pd, Mf, Pa, Pt, Sc, Si except Ma, also Zinc inversely proportion to T-score of Hy, Mf, Pa, Pt. These results suggest that difference of some hair mineral contents exist between criminal and normal control group. Thus further studies are necessary to determine whether violent and nonviolent criminal group attributed biochemical imbalance with carefully constructed and controlled studies.

• Korean Journal of Ecology and Environment
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• v.33 no.3 s.91
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• pp.187-196
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• 2000

This paper describes a simple method that uses differences among Carlson's (1977) trophic state index (TSI) values based on total phosphorus (TP), chlorophyll a (CHL) and Secchi depth (SD) to draw inferences regarding the factors that are limiting to phytoplankton growth and the composition of lake seston. Examples are provided regarding seasonal and spatial patterns in a large subtropical lake (Lake Okeechobee, Florida, USA) and inter- and intra-lake variations from a multilake data set developed from published studies. Once an investigator has collected routine water quality data and established TSI values based on TP, CHL, and SD, a number of inferences can be made. Additional information can be provided where it also is possible to calculate a TSI based on total nitrogen (TN). Where TSI (CHL)<>TSI (SD), light attenuating particles are large (large filaments or colonies of algae), and the phytoplankton may be limited by zooplankton grazing. Other limiting conditions are inferred by different relationships between the TSI values. Results of this study indicate that the analysis is quite robust, and that it generally gives good agreement with conclusions based on more direct methods (e.g., nutrientaddition bioassays, zooplankton size data, zooplankton removal experiments). The TSI approach, when validated periodically with these more costly and time-intensive methods, provides an effective, low cost method for tracking long-term changes in pelagic structure and function with potential value in monitoring lake ecology and responses to management.

• Journal of Life Science
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• v.14 no.1
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• pp.1-7
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• 2004

The root of Stnchys Sieboldif MIQ was extracted three times with methanol and extract was found to contain 3.02% of polyphenols and 1.97% of flavonoids. DPPH radical scavenging method, ferric thiocyanate method, and nitrite scavenging ability method were employed to investigate the constituents of the extract and to measure their activity on antioxidation. The fraction extracted by ethylacetate showed higher anti oxidation value than that of $\alpha-tocopherol$, butylated hydroxyanisole (BHA), and butylated hydroxytoluene (BHT) at the same concentration. UV-VIS spectral data of the extract by ethylacetate that was isolated on a silica gel column proved adsorption maxima in the range of 280∼330 nm. The fraction ES-RS that has $\lambda_{max}(nm)$ of band 1, 325nm and band II, 289nm exhibitd the strongest activity on antioxidation. ES-R5 fraction showed similar pattern to flavones by the analysis of UV-VIS spectral data.

• Korean Journal of Medicinal Crop Science
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• v.9 no.2
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• pp.116-123
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• 2001

This study was carried out to investigate antioxidative, antimicrobial activity and the effect on hepatotoxicity in various extracts of Artemisia iwayomogi. The herb has been used widely for jaundice, hepatitis and liver cirrhosis in chinese medicine. Solid yield by various extraction solvents, 18.1%, was the highest in water extract. To find antioxidative activity in Artemisia iwayomogi was estimated radical scavenging effect by DPPH method in various extracts and change of the POV(peroxide value) of various extracts added in soybean oil during 20 days at $60^{\circ}C$. Radical scavenging effect by DPPH method was the most effective in methanol extract. Added 1,000ppm water extract and methanol extract in soybean oil, the POV of them, 46.8(meq/kg) and 50.8(meq/kg) were lower than that of control, 79.1(meq/kg), during 20 days storage. After antimicrobial activity of various extracts of Artemisia iwayomogi on bacteria was carried out by paper disc method, it found that the ethanol extract was the strongest activity on Vibrio parahaemolyticus. In vivo experiment was to investigate the effect of Artemisia iwayomogi water extract(AIWE) on hepatotoxicity by carbon tetrachloride$(CCl_4)$ in rats. The experiment groups were divided into five groups for recovery(for 3 days) and three groups for protection(for 10 days) in rat liver. The weights and morphological changes of liver and the body weight were examined in each groups. Compared with $CCl_4$ treatment groups$(CCl_4\;only)$, liver and liver/body(%) weights of AIWE pretreatment groups for 3 days and AIWE posttreatment groups for 10 days were declined. In macrography, fibrious exudates and swelling of liver were decreased in AIWE treatment groups. Accumulation of lipid droplets and necrosis of hepatocytes were also decreased in AIWE treatment groups in microscopically. In these results, AIWE seems to enhance hepato-protective and recoverable effect on $CCl_4$ induced hepatotoxicity in rats.