• Tribology and Lubricants
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• v.17 no.6
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• pp.459-466
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• 2001

In this study, the effects of oxide layer formed on the contact parts of TiN coated ball and steel disk on friction characteristics in various sliding conditions were investigated. AISI52100 steel ball was used for the substrate of coated ball specimens, which were prepared by depositing TiN coating with 1(m in coating thickness. AISI1045 steel was used for the disk type counter-body. To investigate the effect of oxide layer on the contact parts of two materials, the tests were performed both in air for forming oxide layer on the contact parts and in nitrogen environment to avoid oxidation. From the test results, the frictional characteristic between the two materials was predominated by iron oxide layer that formed on wear tract of counter-body and this layer caused friction transition and high friction. And the adhesive wear occurred from steel disk to TiN coated ball caused the formation of oxide layer on counter parts between the two materials.

• Journal of Veterinary Clinics
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• v.15 no.2
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• pp.255-262
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• 1998

Lateral laminectomy was performed far spinal decompression in 7 thoracolumbar disc herniated dogs. These dogs showed upper motor neurologic signs including kyphosisi urinary dysfunction, and paraplegia or paralysis in hindlimbs. The lesions were evaluated with myelographic findings and predominated in $T_{12}-T_{13}, T_{13}-L_{1} and L_{1}-L_{2}$ discs. Five dogs which were operated within 48 hours after the onset of paraplegia were recovered from kyphosis and sustained the normal gait and walkings furthermore normal urination and defecation were presented within 3 days of postoperation. One dog was expired with steroid induced intestinal bleeding. The other dog operated on 96 hours after the onset of paraplegia was not recovered from neurologic deficits. Spinal decompression technique was considered to be useful method fur improving neurological problems resulted firom thoracolumbar disc herniation, if dogs are operated on early stage of the onset of paraplegia.

• Korean Journal of Veterinary Research
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• v.24 no.1
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• pp.36-39
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• 1984

The present survey was undertaken to determine the mycoflora of broiler houses. Attempts were made to isolate and identify fungi in the dust, feed, litter and water from 21 broiler houses. A total of 166 isolates of fungi was identified as yeast spp. (44%), Aspergillus spp. (30.7%), Verticillium spp. (7.2%), Penicillium spp. (3.6%), Paecilomyces spp. (3.6%), Scopulariopsis spp. (3.0%), Cephalosporium spp. (3.0%), Chrysosporium spp. (2.4%), Cladosporium spp. (1.8%) and Absidia spp. (0.6%). Isolated of Aspergillus(A) spp. and Penicillium(P) spp. were identified as A. fumigatus, A. flavus, A. terreus, A. nidulans, A. niger, P. citrinum and P. palitan. Fungal contamination of the broiler houses predominated in the dust. The important point is that must of the isolates were pathogenic fungi.

• Environmental Engineering Research
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• v.11 no.6
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• pp.293-302
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• 2006

The reaction of ozone with NOM (Natural Organic Matter) can occur by two different pathways: that involving molecular ozone and by way of reactions with hydroxyl radicals which are produced from the decomposition of molecular ozone. As such, the formation of ketoacids and Assimilable Organic Carbon (AOC) can be controlled by controlling the pathway by which ozone reacts with NOM. The ratios of $[OH{\cdot}]/[O_3]$ ($R_{CT}$ values) were determined under the various ozonation conditions. The $R_{CT}$ values increased with increasing initial ozone concentration. The $R_{CT}$ values (ranges from 10 to $35^{\circ}C$) increased linearly as temperature increased (within the range from 10 to $35^{\circ}C$). However, $R_{CT}$ was independent of hydraulic retention time (HRT). Operational conditions were found to affect the formation of AOC. The conditions where the molecular ozone reaction predominated resulted in an increase in the formation of AOC.

• Journal of Environmental Health Sciences
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• v.22 no.4
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• pp.55-61
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• 1996

Measurements of the seasonal variations of concentration and size distribution of TSP, $SO_4^{2-}, NO_3^-, Cl^-, NH_4^+, Na^+, K^+, Ca^{2+}$ and $Mg^{2+}$ were made by Andersen air sampler from May 1995 to April 1996 in Seoul. The size distribution of these ions was divided into four patterns. 1) Distribution was concentrated on fine particles over a year such as $NO_3^-$ component, 2) Distribution was predominated in coarse particles fraction over a year such as $Mg^{2+}$ and $Ca^{2+}$ components, 3) Distribution was differerent from various seasons such as $NH_4^+, SO_4^{2-}, Cl^-$ and $K^+$ components, 4) Distribution was bi-modal such as $Na^+$.

• Korean Journal of Medicinal Crop Science
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• v.18 no.3
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• pp.191-200
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• 2010

Anthocyanin and polyphenolic compounds present in fruits of mulberry (Morus alba L.) were determined and the influence of temperature and UV irradiation on stability of the anthocyanin-copigment complex were investigated. The copigmentation substance selected in non-anthocyanin fraction from mulberry for the study included: phenolic acid (hydroxybenzoic acid) and flavonoid (quercetin-3-O-$\beta$-D-glucopyranoside). The copigmentation effect increased with the copigment content. UV irradiation had a stronger degradation effect on the copigmentation complex than heating at $80^{\circ}C$. The non-anthocyanin fraction of mulberry and isolated flavonoid (quercetin-3-O-$\beta$-D-glucopyranoside) from mulberry fruit predominated over other copigment substances.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.7 no.2
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• pp.51-59
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• 2002

The seasonal variation in species composition and abundance distribution of zooplankton was studied in the Seomjin river estuary along the salinity gradients. In this estuary, marine taxa predominated in all seasons and very limited number of freshwater species appeared. The total abundances showed a seasonal fluctuation. The highest total abundance appeared in spring with over 3,000 individuals/m$^3$. In summer, the high abundance was sustained although it decreased a little. The abundance was minimal in fall with about 500 individuals/m$^3$. When the study area was divided into three salinity regimes, oligohaline (salinity less than 5 psu), mesohaline (5${\sim}$18 psu), and polyhaline zone (over 18 psu), the zone of high abundance as well as the composition of zooplankton community in each salinity regime changed seasonally. In fall, marine copepods predominated in oligohaline zone while marine species other than crustaceans dominated in polyhaline zone. However, in winter copepods predominated in all area. In spring and summer, holozoic dinoflagellate Noctiluca scintillans dominated in higher salinity regimes. We listed major copepod species of each salinity regime for each season with the ranges of water temperatures (T) and salinities (S) of their occurrence. T, S's of maximum abundances of those major copepod species were also reported. The observed very wide tolerance ranges of major copepod species for salinity suggested that the concept of 'indicator species' should be used in quantitative context rather than qualitative.

• Korean Journal of Environment and Ecology
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• v.24 no.6
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• pp.708-722
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• 2010

This study was carried out to classify vegetation structure of the Hyangjeokbong in the Deogyusan National Park using the gradient analysis and phytosociological method. The vegetation was classified into Quercus mongolica community(Rhododendron schlippenbachii subcommunity, typical subcommunity), Q. serrata community, Q. variabillis community, Pinus densiflora community, Cornus controversa community, Fraxinus mandshurica community and Taxus cuspidata community. Ecological characteristics such as species composition, layer structure, vegetation ratio, and the distribution of individual trees by DBH(diameter at breast height) were significantly different among communities. The order of important value of the forest community with DBH 2cm above plants was Q. mongolica(81.2), F. mandshurica, Q. serrata, P. densiflora, Acer pseudosieboldianum, Q. variabillis, Rhododendron schlippenbachii, C. controversa, T. cuspidata. Distribution of DBH of Q. mongolica and Q. serrata had suggesting a continuous domination of these species over the other species for the time being. In contrast, F. mandshurica appeared limited to the valley of the sheet and a higher frequency of young individuals, suggesting a continuous domination of these species the development of a climax forest terrain. P. densiflora and T. cuspidata had suggesting a continuous domination of these species over the other species for the time being in maintain. Q. variabilis and C. controversa had a formality distribution, suggesting a continuous domination of these species over the other species for the time being. This study examined the correlation between each community and the environment according to DCCA ordination. The Q. mongolica community and T. cuspidata community predominated in the highest elevation habitats which had few moisture, Ca and in the low pH. The Q. serrata community mainly occurred in the low elevation habitats which had many moisture. P. densiflora community predominated in the middle elevation and south-facing slope habitats which had few moisture, Ca and in the low pH. F. mandshurica community predominated in the low elevation habitats which had many moisture, Ca and pH.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.2
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• pp.319-326
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• 1997

This study was conducted to investigate the effects of methionine(Met) and selenium(Se) levels on alcohol metabolic enzyme system in rats. Sprague-Dawley male rats were fed on diets containing one of the three levels of Met(0, 3, 9g/kg diet) with or without Se(0.45mg/kg diet). Alcohol was administrated with 25%(v/v) ethanol orally at the same time once a day in alcohol group and isocaloric sucrose was administrated to the control group. The rats were sacrificed after 5 and 10 week of feeding periods. Alcohol dehydrogenase(ADH) and microsomal ethanol oxidizing system(MEOS) activities of hepatic tissuedom were increased more in alcohol treated groups than control group. Increment of activities preinated in simultaneous deficiency of dietary Met and Se(LMet-Se+EtOH) group. Aldehyde dehydrogenase (AIDH) activity was decreased more in alcohol treated groups than control group and significantly decreased in Met and Se supplemented(NMet+Se+EtOH) group. Hepatic cytochrome P-450 content and xanthine oxidase(XO) activity were significantly increased in alcohol treated groups Compared to control group and predominated in Met deficiency(LMet) group and excessive Met administration (HMet) group. Superoxide dismutase(SOD), catalase, glutathione S-transferase(GST) activities tended to increase by alcohol administration, the degree of increase predominated in 10 week. The activity of glutathione peroxidase(GSH-Px) was decreased in alcohol groups and tended to increase in proportion to the level of dietary Met.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.4
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• pp.640-651
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• 1997

This study was performed to examine the distribution patterns, ecological characteristics and celluar fatty acid compositions of marine bacteria in Suyeong Bay. During study periods, total cell count (TC) and viable cell count (VC) were $10^7-10^8/m\ell\;and\;10^4-10^6\;cfu/m\ell$, respectively. The temporal variations of TC showed similar patterns between surface and bottom layer, but the VC at bottom decreased gradually from winter to summer. Among the 303 bacterial strains isolated in the study area, which belong to 10 genus types, Pseudomonas spp., $(32.3\%)$, Acinetobader sup. $(19.1\%)$, Vibrio spp. $(11.2\%)$, Flovobacterium spp. $(10.6\%)$ and Bacillus spp. $(7.9\%)$ were dominant. Thirty-one fatty acids were detected from Pseudomonas spp. and Bacillus spp., which were the most predominated among Gram positive and Gram negative bacteria. Celluar fatty acid compositions of Bacillus spp. were relatively simple compared to those of Pseudomonas spp.. Relatively high ratio of monounsaturated forms were detected in Pseudomonas spp. while branched types were dominant in those of Bacillus spp.. Hydroxy and cyclopropane fatty acid were detected only in the cellular fatty acid of Pseudomonas spp.. Cellular fatty acid compositions of Pseudomonas spp. revealed relatively high percentage of $C_{16:1},\;C_{17:1},\;C_{18:1}\;and\;C_{16:0}$, While Bacillus spp. predominated $C_{16:0}\;iso\;C_{16:0}\;anteiso,\;C_{17:0}\;anteiso\;and\;C_{16:1}$.