• Economic and Environmental Geology
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• v.17 no.2
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• pp.115-139
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• 1984

The Cu-Pb-Zn-Ag hydrothermal vein-type deposits which comprise the Sambong mine occur within calc-alkaline volcanics of the Cretaceous Gyeongsang Basin. The ore mineralization took place through three distinct stages of quartz (I and II stages) and calcite veins (III stage) which fill the pre-existing fault breccia zones. These stages were separated in time by tectonic fracturing and brecciation events. The reflection variations of one mineral depending on mineralization sequence are considered to be resulted from variation in its chemical composition due to different physico-chemical conditions in the hydrothermal system. The reflection power of sphalerite increases with the content of Fe substituted for Zn. Reflectances of the sphalerite grain are lower on (111) than on (100) surface. The spectral profiles depend on the internal reflection color. Sphalerite, showing green, yellow and reddish brown internal reflection, have the highest reflection power at $544m{\mu}$ (green), $593m{\mu}$ (yellow) and $615m{\mu}$ (red) wavelength, respectively. Chalcopyrite is recognized as biaxial negative from the reflectivity data of randomly oriented grains measured at the most sensitivity at $544m{\mu}$. The microindentation hardness against the Fe content (wt. %) for the sphalerite increases to 8.05% Fe and then decreases toward 9.5% Fe content. Vickers hardness of the sphalerite is considerably higher on surface of (100) than on (111). The relationship between Vickers hardness and crystal orientation of the galena was determined to be $VHN_{(111)}$ > $VHN_{(210)}$ > $VHN_{(100)}$. The softer sulfides have the wider variation of the diagonal length in the indentation. Diagonal length in the indentation is pyrite

• Korean Journal of Agricultural and Forest Meteorology
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• v.7 no.4
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• pp.265-273
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• 2005

Chemical properties and heavy metal concentrations of forest soils of four abandoned coal mine lands affected by coal mining activities in the Mungyeong area were investigated to provide basic information for revegetation of abandoned coal mine lands. Soil pH in abandoned coal mine lands ranged from 5.30 to 6.76 it in the control site was 5.23. Contents of organic matter and total N in abandoned coal mine lands were $4.46\~7.19\%\;and\;0.07\~0.15\%$, respectively. Available P contents were 6.54 for A (Samchang), 6.52 for B (Bongmyeong),3.94 fur C (Kabjung), 5.45 mg/kg for D (Danbong coal mine land) and 5.25 mg/kg for the control site, which had a positive correlation with soil pH. Contents of exchangeable Ca, Mg, K and Na in abandoned coal mile lands averaged 196.1, 88.7, 88.2 and $10.2cmol^+/kg$, with a range of $132.1\~242.1,\;24.2\~138.\; 64.9\~120.8\;and\;8\~12.2cmol^+/kg$, respectively. Those of the control site were 192.8, 95.8, 104 and $21.2 cmol^+/kg$, respectively. Heavy metals such as Al, As, Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn of forest soil in abandoned coal mine lands have a larger content than those of the control site. Al, Mn and fb content was especially high in abandoned coal mine lands. The Al content of forest soil in abandoned coal mine lands ranged from 397 to 917 ppm, which was considered to be high enough to inhibit tree growth. Therefore, it is suggested that soils of abandoned coal mine lands contaminated by mining activities need to be properly treated for remediation of environmental problems.

• Economic and Environmental Geology
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• v.41 no.4
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• pp.405-425
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• 2008

In order to investigate the amounts of trace elements flowing into reservoir, and to elucidate the relationship between trace element mobility and fraction size, the stream water and sediment samples were collected from thirty-two sites of the 3rd or 4th order stream within watershed surrounding the Juam reservoir. Chemical analyses of trace elements (As, Cd, Cr, Cu, Ni, Pb and Zn) for all samples were completed, and additionally cationi and anion for stream water samples. Considering the distribution of rocks and contamination sources in watershed, the eight stream sediments were selected from typical sites representing study areas, and we determined the concentrations of trace elements according to size fractions ($2\;mm{\sim}200\;{\mu}m$, $200{\sim}100\;{\mu}m$, $100{\sim}50\;{\mu}m$, $50{\sim}20\;{\mu}m$ and < $20\;{\mu}m$). The correlation relationships between concentrations and size fractions of stream sediments were important to identify the hydro-geochemical behavior of trace elements that flow into Juam reservoir. Stream waters showed four water types (Ca-Mg-$HCO_3$, Ca-Na-$HCO_3$-Cl, Ca-Na-$HCO_3-SO_4$, Ca-Na-$HCO_3$) depending on pollution sources such as coal mine, metal mine, farm-land and dwellings. Concentrations of trace elements increased clearly with the decrease in size fractions of stream sediments. Concentrations of Cu, Pb and Zn increased dramatically in silt size (< $20\;{\mu}m$) fraction, while As had high concentrations in sand size ($2\;mm{\sim}100\;{\mu}m$) fraction in downstream sediments of metal mines. These indicate that Cu, Zn, and Pb moved into Juam reservoir easily in the adsorbed form on silt size grain in sediments, and As was transported as As-bearing mineral facies, resulting in its less chance to reach into Juam reservoir.

• Korean journal of applied entomology
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• v.24 no.3 s.64
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• pp.123-127
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• 1985

Incidence of the Fusarium wilt caused by F. oxysporum f. sp. vasinfectum of sesame (var. Kwangsan) was remarkably influenced by seeding date and mean air temperature in the field of two or three year's continuous cropping with sesame in 1983 and 1985. Sesame were seeded on six different dates from April 20 to July 5. Air temperature was checked daily at the meteorological station near the experimental field. Low($16{\sim}20^{\circ}C$) and high temperature($20{\sim}25^{\circ}C$) periods were provisionally devided, based on every ten-day mean daily temperature during field experiment for last ten years, which corresponded to before and after June 15 in Jinju, Gyeong-nam. Infection rates were 83.7%, 68.2% and 59.4% in the plants grown for 55 days (seeding date: April 20), 40 days(May 5) and 25 days(May 20) under low temperature. On the other hand, infection rates were below 3% in those plots seeded during high temperature period. The longer the growth period exposed to low temperature, the higher was infection rates. It is interesting to note that 40 days old seedling or older are prone to severe infection compared to the younger ones, in higher temperature of $20{\sim}25^{\circ}C$. Therefore, seedlings in vegetative growth stage are less prone to infection than these in reproductive growth stage. The result showed that air temperature during sesame growth was one of the most important factor affecting the incidence of Fusarium wilt. This suggested that sesame crop, which is of tropical origin, has been predisposed to Fusarium wilt, when the plants were exposed to low temperature of $16{\sim}20^{\circ}C$.

• Korean Journal of Environmental Agriculture
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• v.25 no.3
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• pp.217-227
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• 2006

Micronutrient status in soils and crops of plastic film house and their relationship were investigated. Total 203 plastic film houses were selected (red pepper, 66; cucumber, 63; tomato, 74) in Yeongnam region and soil and leaf samples were collected. Hot-water extractable B and 0.1 N HCl extractable Cu, Zn, Fe, and Mn in soil samples and total micronutrients in leaf samples were analyzed. Contents Zn, Fe, and Mn in most of the investigated soils were higher than the upper limits of optimum level for general crop cultivation. Contents of Cu in most soils of cucumber and tomato cultivation were higher than the upper limit of optimum level, but Cu contents in about 30% of red pepper cultivation soils were below the sufficient level. Contents of B in most soils of cucumber and tomato were above the sufficient level but in 48% of red pepper cultivation soils B were found to be deficient. Micronutrient contents in leaf of investigated crops were much variable. Contents of B, Fe, and Mn were mostly within the sufficient levels, while in 71% of red pepper samples Cu was under deficient level and in 44% of cucumber samples Cu contents were higher than the upper limit of sufficient level. Contents of Zn in red pepper and cucumber samples were mostly within the sufficient level but in 62% of tomato samples Zn contents were under deficient condition. However, any visible deficiency or toxicity symptoms of micronutrients were not found in the crops. No consistent relationships were found between micronutrient contents in soil and leaf, and this indicates that growth and absorption activity of root and interactions among the nutrients in soil might be important factors in overall micronutrient uptake of crops. For best management of micronutrients in plastic film house, much attention should be focused on the management of soil and plant characteristics which control the micronutrient uptake of crops.

• Journal of Nutrition and Health
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• v.49 no.6
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• pp.495-505
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• 2016

Purpose: This study was conducted to investigate and analyze the association between stress from shift and non-shift work as well as the effects living habits have on eating habits in order to identify why and how workers can improve their health and form proper eating habits for higher working efficiency. Methods: The subjects of this study were 361 workers from K manufacturing company from April 7 to 11, 2014 and they were surveyed using a questionnaire. The subjects were divided into two groups according to working pattern: shift workers (n = 216) and non-shift workers (n = 110). Results: In the general characteristics, there were significant differences in age, work career, work time, marriage, monthly income, and education levels between the two groups. For healthy behaviors, significant differences in subjective health status, moderate physical activity, drinking, smoking, and sleep time were observed between shift workers and non-shift workers. For eating habits, scores of non-shift workers having a regular mealtime, balanced meal composition, and vegetable and seaweed intakes were significantly higher than those of shift workers. The sum score of dietary habits in non-shift workers was also significantly lower than that in shift workers (p < 0.05). Total job stress score did not significantly differ between the two groups. Conclusion: The sum of eating habit scores according to work types was $16.1{\pm}0.6$ in non-shift workers and $14.0{\pm}0.3$ in shift workers. These results suggest that it is necessary to provide food suitable to characteristics of different workers according to work type which should be provided along with daily nutrition counseling to help subjects recognize their status.