• Korean Journal of Soil Science and Fertilizer
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• v.49 no.6
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• pp.768-775
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• 2016

Heavy metal pollution in arable field is an critical problem due to crop safety. For this reason, national survey of heavy metal pollution in the arable field near at the industrial area has been conducted from 1999 in Korea. The main purpose of this research was to monitor heavy metal pollution in Chungnam/chungbuk province and to evaluate pollution index (PI) in soil. Total of 15 sampling locations were examined and average concentration of each heavy metals were following: As - $2.99{\pm}2.63$, Cd - $0.23{\pm}0.07$, Cu - $9.35{\pm}6.48$, Ni - $9.26{\pm}8.03$, Pb - $10.18{\pm}3.32$, Zn - $52.9{\pm}17.18$. No sampling site was exceeded threshold level of each heavy metals. Calculated PI in soil was ranged between 0.03 - 0.27 indicating that also no heavy metal pollution is occurred in examined sampling locations. Although, no heavy metal pollution was observed in the examined sites but monitoring of heavy metal pollution should be continued for possible accidental pollution in arable field near at the industrial area.

• Journal of Korean Society for Atmospheric Environment
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• v.21 no.6
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• pp.613-624
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• 2005

In this study, we investigated the characteristic of volatile organic compounds (VOCs) concentrations in Shiwha area, which were measured using the Open-path FTIR Gas Analyzer. The passive samplers were set for a certain period of time to obtain the average concentration of toluene, ethylbenzene, o-xylene and styrene. In addition, VOCs concentration contour maps were constructed using the Tecplot program to illustrate the VOCs concentration distribution. The residential area showed higher concentrations than the industrial area. And the summer had higher concentration value than the winter. Also, we confirmed that the VOCs concentrations ranged from 2 to several tens ppb in the vicinity of an industry than diffused VOC concentration, whereas those ranged from 0 to 5 ppb in most other areas. It was conferred that the wind change with seasons significantly affects the distribution of VOCs concentrations such as a northwesterly wind in the winter or a southwestern wind in the summer.

• Korean Journal of Veterinary Research
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• v.29 no.1
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• pp.1-6
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• 1989

The number and distribution of the retinal ganglion cells in the 2 years old Korean native cattle was determined from whole fiat mounted preparation stained with methylene blue and thionin. The results were summarized as follows. 1. The total number of retinal ganglion cells was estimated to be 3,085,200 in the bovine retina ranging from $2,214mm^2$ in total area. 2. Visual streak was recognized at the area 2.5mm superior to the optic disc and ganglion cell density drops off rapidly to the directions superior to and inferior to the visual streak. 3. Area centralis ($6,800cells/mm^2$) was located at the area 10mm temporally from the point of 3mm superior to the optic disc. 4. The number of ${\alpha}-type$ ganglion cells (above $15{\mu}$) was 57,000 in the bovine retina and ${\alpha}-type$ ganglion cells constituted 18.5% of the total cells. 5. The relative frequency of ${\alpha}-type$ ganglion cells was higher in the peripheral regions than in the visual streak, especially higher in the superior-temporal quadrant than in other region of the bovine retina.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.7 no.2
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• pp.62-67
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• 2004

Forest community structure analysis in the Seooreung area, Goyang-si was carried out to supply basic data for reasonable management and conservation. The forest vegetation of the Seooreung area was classified into Alnus japonica community, Quercus mongolica - Carpinus laxiflora community, Quercus serrata community, and Pinus densiflora community. The dominant species in the area were in the order of Quercus mongolica, Quercus serrata, Robinia pseudoacacia, Quercus variabilis, Quercus aliena, Styrax japonica, Pinus rigida, and Alnus hirsuta. According to the DBH analysis result, Pinus densiflora was dominance species in Tomb area. Pinus rigida had a density of normal distribution style in the entire forests, therefore, their dominance are expected to continue for now. However, Quercus serrata is expected to extend their influence in the future in competition with Pinus rigida. Quercus mongolica had a density of normal distribution style in the Quercus mongolica - Carpinus laxiflora community, therefore, their dominance are expected to continue for now. Carpinus laxiflora is expected to extend their influence in the future in competition with Quercus mongolica. The relationship between the distribution of dominant species of forest vegetation and soil condition in Seooreung area was investigated by analyzing soil nutrition and moisture gradient. Alnus hirsuta community was distributed in the mesic and medium nutrition area and Quercus mongolica - Carpinus laxiflora community in the serix and relative good nutrition area. Pinus densiflora community was distributed in the serix and poor nutrition area and Quercus serrata community in the subserix and medium nutrition area.

• Korean Journal of Weed Science
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• v.16 no.4
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• pp.259-263
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• 1996

Occurrence and distribution of weeds were surveyed in autumn vegetable crops(Chinese cabbage, radish, cucumber and Welsh onion) in 16 cities or counties of Chungnam area during October and November 1995. Thirty weed species were occurred, and Rorippa globosa, Alopecurus aequalis var. amurensis, Stellaria media, Portulaca oleracea, Digitaria sanguinalis and Chenopodium album var. centrorubrum showed higher importance values among them. S. media, P. oleracea and A, aequalis var. amurensis were dominant in northwest coastal area, R globosa, D. sanguinalis and S. media in southwest coastal area, R globosa, A. aegualis var. amurensis and D. sanguinalis in northern area, and R globosa, A. aequalis var. amurensis and P. oleracea in southern area. S. media, R globosa and P. oleracea were dominant in Chinese cabbage fields, R globosa, Amaranthus retroflexus and S. media in radish fields, A. retroflexus, S. media and D. sanguinalis in cucumber fields, and R. globosa and P. oleracea in Welsh onion fields.

• Proceedings of the Korean Society of Crop Science Conference
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• 2020.11a
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• pp.125-125
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• 2020

• Carbon letters
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• v.10 no.4
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• pp.339-344
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• 2009

Henequen fiber was air-stabilized, carbonized, and steam-activated to obtain high surface area activated henequen fiber (AHF). Thermal behavior of henequen fibers has been studied by TGA. The structural morphology and characteristics were observed by SEM and BET surface area measurement. The yield of AHF from natural henequen was in the range of 20~25 wt%. Mesopores (2~2.5 nm) were developed on the AHF as the activation temperature was raised up to $700^{\circ}C$, and the band of mesopore size distribution moved to 15~30 nm when the activation were carried out at $900^{\circ}C$ for 30 min. The specific surface area and the total pore volume were about $1394\;m^2/g$ and $1.30\;cm^3/g$, respectively at this activation conditions.

• Korean Journal of Agricultural Science
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• v.15 no.2
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• pp.174-180
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• 1988

Land reform in Korea was performed in 1949. The formation of owner farmers was the primary objective of land reform. But since land reform, the number of tenants has been increasing, and it reached to 65.7% of total farmhousehold by 1985. To analyze the productivity of tenant farming, 40 farmers in Kumnam, Yeongi Gun and Gongju Gun, Banpo, Chungnam Province, were selected as samples for the empirical analysis. The results of the empirical analysis are summarized as follows; 1. In plain area, tenants input 5% more labor, and 15% less capital than owner farmers. In mountain area, tenants input 15% more labor, and 4% more capital than owner farmers. 2. There is no difference in the output of rice between owner farmers and tenants in both area. 3. In plain area, the physical productivity of labor of owner farmers is 4.6 (kg/hour), and that of tenants is 4.4. And the physical productivity of labor of owner farmers in mountain area is 4.2, and that of tenants is 3.6. 4. The physical productivity of capital of owner farmers in plain area is 17.7(kg/1,000 won), and that of tenants is 20.6. In mountain area, the physical productivity of capital of owner farmers is 18.8, and that of tenants is 17.9.

• Korean Journal of Veterinary Service
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• v.36 no.2
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• pp.147-150
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• 2013

This study was carried out to investigate the prevalence of honeybee (Apis mellifera) disease in cheonan and asan area. From September to November in 2012, 33 samples were collected from 33 apiculture farms in the regions and reverse transcriptase-polymerase chain reaction (RT-PCR) and polymerase chain reaction (PCR) was conducted. Among 33 samples, prevalence rate was 42% in Sac Brood Virus (SBV), 52% in Nosema, 21% in American foulbrood (AFB), 70% in European foulbrood (EFB), 97% in Stonebrood, 3% in Chalkbrood. The result indicate that stonebrood was most prevalent disease in apiculture farms in cheonan and asan area.

• Korean Journal of Veterinary Research
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• v.54 no.1
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• pp.53-54
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• 2014

This study was conducted to determine the serum cardiac troponin I (cTnI) concentrations in clinically normal (uninfected) Korean Jindo dogs and those infected with Dirofilaria (D.) immitis. Forty Korean Jindo dogs (22 females, 18 males) were obtained from two kennels in the Boryeong area of Chungnam Province and the Daejeon area, Korea. Significantly higher cTnI concentrations were observed in D. immitis-infected dogs than clinically normal dogs. cTnI testing in addition to thoracic radiography, echocardiography, and electrocardiography shows promise as an additional method for diagnosis of heartworm infection.