• Journal of Food Hygiene and Safety
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• v.3 no.1
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• pp.7-18
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• 1988

In 1987, the level of heavy metals were determined ina total of 200 samples of 9 species of shellfish of Korea. The samples were collected at the fish. markets by 10 Public Institute of Health. The samples were whelk (Buccinum striatiBBimum), oyster (Crassostrea gigas), ark shell(Tegillarca granesa), shartnecked clam (Venerupis semidecussta), hard clam (Meretrix lusoria), top shell (Turbo cornutus), abalone (Haliotis gigantea), ark shell (Scapharea broughtonii), sea-mussel (Mytilus conuscus gould), respectively. The levels of total mercury, lead, cadmium, arsenic, copper, zinc and manganese were determined. The total mercury levels were determined by mercury analyzer using the combustion gold amalgamation method. The arsenic level were determined by spectrophotometry using colorimetric sil ver diethyldithiocarbamate method after dry ash dige8tion of the samples with magnesium oxide and magnesium nitrate. The levels of other metals were determined by inductively coupled pluma spectrophotometry after wet digestion of the samples with nitric acid and su1furic acid. The results were summerized as follows; 1. The overallranges and mean(ppm) were; Hg, ND-O.221 (0.036); Pb, 0.05-1.51 (0.37); Cd, 0.02-1.86 (0.61); As, 0.5-3.97 (1.22); Cu, 0.14-54.16 (4.93); Zn, 7.40-207.17 (30.09); Mn, 0.13-s.72 (3.40). 2. The levels of all 6 metals were found to be below the maximum permissible Iimits set by the Japan lor mercury, the Netherland for lead the Hong Kong for cadmium. The Finland for Arsenic no statutory Iimits for Zn and Mn in shellfish in any countries. 3. The results show that all the 9 species of shellfish studied, none have accumulated levels dangerous enough to pose a health problem.roblem.

• Journal of Nutrition and Health
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• v.1 no.1
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• pp.9-18
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• 1968

Dividing into six(6) experimental groups; Stock Diet(SD) Group, Rice Diet(RD) Group, Rice Diet supplemented with Barley(RD-BD) Group, Barley Diet(BD) Group, Rice Diet supplemented with Millet(RD-MD) Group, and Millet Diet(MD) Group, biochemical and nutritional effects of rice, barley, and millet on rats are studied. The grains used in this experiment are polished ones and purchased from market. Six(6) weaning male albino rats are housed into the individual cages in each group and fed with each experimental diet and water ad libitum for 21 weeks. The composition of the experimental diets are shown in Table 1. At the end of experiment, the appearences of rats are observed and the bloods are sampled by heart puncture method following ether anesthesia for determinations of serum protein and serum cholesterol. And the livers are sampled immediately right after heart after heart puncture for determinations of liver weight, liver nitrogen, liver fat, and liver glycogen. And also liver tissues are observed histologically. The result of growth experiment is shown in Table 2 and Figure 7. The results of blood analysis are shown in Table 3 and the results of liver analysis are shown in Table 4. And the histological observations of liver tissue are shown in Figures 1, 2, 3, 4, 5, and 6. According to the above results, it could be summarized as follows; 1) The normal appearences are observed at SD Group and BD Group. Alopecia is observed at RD, RD-­BD, RD-MD, and MD groups and the wet appearences of hair are observed at RD-MD and MD groups. The color of hair is changed to yellowish white at RD, RD-MD groups. The maximum growth inhibition, is observed at MD group and the growths of RD, RD-BD, BD, and RD-MD groups are significantly lower than that of SD group. The growth of RD group is lower than those of RD-BD and BD groups, though this difference is not significant. 2) At the blood analysis, the highest serum protein content is shown at SD group and the lowest serum protein is observed at MD group. The serum cholesterol contents are not significantly different among the six(6) experimental groups. 3) The highest liver weight is observed at SD group and the lowest weight is shown at MD group. However, oppositely the highest liver weight per 100 grams of body weight at MD group and the lowest liver weight per 100 grams of body weight at SD group are observed as shown in Table 6. 4) The differences of liver nitrogen contents of RD, RB-BD, BD, RD-MD, and MD Groups are not significant except SD group showing the highest content. 5) The significant highest content of liver fat is observed at RD group and the lowest content of liver fat is shown at SD group. And no significant differences in contents of liver glycogen are observed among the six(6) experimental groups. 6) No significant abnormal histological changes of liver tissue are observed at SD, RD-BD, and BD groups. However, the fat metamorphosis at peripheral zone of liver tissue is observed at RD Group and the some histological abnormal changes are observed at RD-MD and MD groups. According to the above summaries, the followings might be estimated and recommended; 1) The BD group shows histological normality of liver tissue, improvement of liver fat and liver nitrogen, normality of appearence, and better growth compared with RD Group. This could be indicated that barley is nutritionally and biochemically better than rice as the feeding diet on rat. And it might be considered that there might be the species speciality for nutritionary evaluation of food. 2) Recently, Marshall indicated that the high consumption of carbohydrate causes fatty liver and Kondo reported that the higher consumption of rice causes the more heart disease and the shorter life span. Considering these reports, the higher consumption of rice as a main dish in our country should be considered as an important national nutritional problem. And this might be improved by supplementing with barley or other grains to rice.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.5
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• pp.643-650
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• 2007

It has been known that Samultang has positive effects on blood circulation and erythrocyte formation. Samultang was composed of four ingredients, Angelica gigas Nikai, Rahmanniae Radix Preparata, Paeonia lactiflora Pallas, and Cnidium officinale Makino. Five types of bread were prepared by replacing water with Samultang for dough proportionally. Control (C) did not have Samultang and the other four experimental bread contained Samultang: S-I (25% of water was substituted by Samultang), S-II (50% substituted), S-III (75% substituted), and S-IV (100% substituted). Moisture, protein, and ash contents of Samultang were $97.34{\pm}0.11%,\;0.42{\pm}0.04%,\;and\;1.40{\pm}0.16%$, respectively. Replacing water with Samultang decreased pH and increased significantly wet gluten content of the dough. Substitution of Samultang for water incremented redness and yellowness of the dough and bread and increased hardness. It also raised the contents of ash and protein. Although it was not significant, in addition, moisture loss of the bread during storage seemed to be lessened by replacing water with Samultang. However, total volume and specific loaf volume of the bread, baking loss rate, and the other textural characteristics except hardness were not affected by substituting water with Samultang. Due to the above results, sensory evaluation of volume and gumminess of the bread were improved significantly by substituting Samultang for water. The bread replaced 25% of the water with Samultang was ranked as the best by the test of sensory evaluation. These results imply that adding Samultang instead of water to dough for bread might bring positive effects on quality characteristics of the bread without any adverse influences. Therefore, it might be worth developing functional bread using Samultang.

• Journal of the Korea Organic Resources Recycling Association
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• v.24 no.3
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• pp.23-33
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• 2016

The characteristics of ammonia generated from alkaline stabilization facilities was investigated which are for organic sewage sludge from wastewater treatment plants. The highest concentration of ammonia was found in mixing and curing process in alkaline stabilization facility and ammonia mainly showed a range of 87.78 ppm($66.62mg/m^3$) to 1,933 ppm($1,467.01mg/m^3$) by detection tube. This is presumed to occur because nitrogen oxides are converted into ammonia as the sewage sludge is mixed with lime. In some facilities, hydrogen sulfide and methyl mercaptan were detected in relatively high concentrations, but odor materials except ammonia were not detected in most of the facilities. The concentration of ammonia caused by process was generally high in the order of "mixing > curing > output > storage > drying > input." It was found that odor compounds are removed by wet absorption using sulfuric acid and sodium hypochlorite in the 5 alkaline stabilization facilities currently in operation. Each facility was designed to meet the concentration of after-treatment emission in 1 ppm($0.76mg/m^3$), 50 ppm($37.95mg/m^3$) or 100 ppm($75.89mg/m^3$), but no facility satisfied the design standard for their emssion limit. In case of ammonia, some workplaces in alkaline stabilization facilities exceeded the exposure limits established by the Ministry of Labor. It appears that proper ventilation should be provided for the safety of workers in future. No odor compound including ammonia was found by detection tubes in the border of the facilities, but trace amounts of odor compounds are expected to exist, given the current operational status of facilities.

• Journal of The Korean Society of Grassland and Forage Science
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• v.39 no.4
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• pp.207-215
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• 2019

This study was conducted to establish spring sowing techniques in preparation for the impacts of climate change on sowing time and wintering rates of winter forage crops such as barley, oat and IRG. Oat showed the highest yield in 2017 which had relatively dry climate condition. And when sowing in late Febrnary 2017 yielding 9,408kg/ha were obtained, yielding 4,011kg/ha more than IRG's sown in the same period. In 2018 which had relatively wet climate condition, four barley species decreased in the production from the previous year. Oat also had decreased by 70% from 9,408kg/ha to 2,851kg/ha. On the other hand, IRG maintained the production in the mid-5,000kg/ha range. It was also found that IRG had the least variability due to external influences regardless of seeding period for 2 years. Mixed sowing with IRG and oat in 50:50 ratio was the highest dry matter, 6,584kg/ha, and IRG was 18.5% and Oat was 2.3 times higher than single planting.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.55 no.1
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• pp.1-7
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• 2010

Stress from excess water is one of the most harmful limiting factor in soybean yield during the wet season under the climate conditions. Soybean is very sensitive to excess water compare to other crops. This experiment was carried out to identify the growth responses for establishing a screening system related to waterlogging tolerance in soybean from 2003 to 2004. The root dry weight accumulation rate of per day for 21 days after waterlogging at V5 stage was the highest in Pungsannamulkong (47~56% of control) and was the lowest in Jangyeobkong (26~27% of control). The nodules dry weight recovery rate was the highest in Pungsannamulkong (83~91% of control), while the lowest in Myungjunamulkong (48~66% of control). After waterlogging, recovery rate of roots was high, which increased the root/shoot ratio of Pungsannamulkong, which also produced significantly more adventitious roots than in Jangyeobkong. The percentage of adventitious roots fresh weight to the total roots fresh weight was the lowest in Myungjunamulkong (14%), while the highest in Pungsannamulkong (38%). This results implies that the water and nutrients absorbing ability of Pungsannamulkong is more higher than that of Myungjunamulkong during late growth period.

• Economic and Environmental Geology
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• v.43 no.4
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• pp.333-341
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• 2010

Fluvial sediments are widely distributed in present and old river-beds of the mid-Keum River, the tributaries of which are the Yugu and Jeongan Rivers. The basement of the mid-Keum River area consists of Mesozoic granites which are easily eroded compared to Precambrian gneisses, which are exposed in the upper-Keum River area. The provenance of the fluvial sediments includes both the Precambrian gneisses and Mesozoic granites, which occur in the catchment of the mid-Keum River. The coarse-grained sediments were probably transported from the river-beds and the overbank floodings of the main Keum River and its tributaries when the climate was warm and wet. The oldest mud deposits were dated at ca. 9,400 yr BP by the radiocarbon method. It has been estimated that the sand deposits below the dated muds were formed in a period from the Late Pleistocene to the Early Holocene. However we have revealed that the major part of the present river-bed sediments was formed at ca. 3,000-6,000 yr BP, i.e., in the mid- to late Holocene, when summer monsoon was very strong due to climatic changes. We have calculated fluvial sedimentation rates of 0.12-0.16 cm/yr and 0.02-0.09 cm/yr for borehole KJ-29 river-bed sediments and borehole KJ-28 floodplain deposits, respectively. We conclude that the sedimentation rate is higher near the present stream channel than near the floodplain.

• Korean Journal of Environmental Agriculture
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• v.19 no.1
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• pp.32-37
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• 2000

Because the household garbage had high water contents, it is difficult to compost it without an additive. Therefore, this study was performed to investigate possibility of using the waste newspapers as a humidity conditioner for the household garbage composting. The maximum temperature was $66.0^{\circ}C$ in spring, $69.2^{\circ}C$ in summer, $60.9^{\circ}C$ in fall and $56.0^{\circ}C$ in winter for composting periods. The seasonal pH value reached around 8.5 after 1 week and then repeated fluctuation at the narrow range in spring and fall, while it was stabilized at the range of $8{\sim}9$ after increasing to 8.5 after 1 week in winter. The water content was reduced little in winter, while decreased significantly in the other seasons. The water content after 8 weeks was 22.2% in spring, 47.6% in summer, 25.5% in fall and 72.5% in winter. The mass was reduced rapidly during the first week of each season, but it did not show much decrease. The volume reduced after 8 weeks to 59%, 32%, 27%, and 34% in spring, summer, fall and winter respectively. Organic matter content decreased over the four seasons. Nitrogen contents were in the range of 0.7% to 2.2% during the four seasons. The contents of inorganic compounds based on dry matyter were in the range of $0.94{\sim}2.59%\;P_2O_5$, $1.23{\sim}1.87%\;CaO$, $0.37{\sim}0.46%\;MgO$, $0.55{\sim}1.98%\;K_2O$. Concentration of heavy metals(Hg, Cd, Pb, Cu, Cr, Zn, As) based on dry matter were less than the limiting value of the by-product compost.

• Economic and Environmental Geology
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• v.36 no.6
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• pp.481-490
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• 2003

The objectives of this study are (1) to determine the extent and degree of As contamination of the water and sediments influenced by mining activity of the abandoned Au-Ag mines, (2) to examine As speciation In contaminated water, (3) to monitor variation of As contamination in water system throughout the dry and wet seasons, and (4) to investigate the As chemical form in the sediments through the sequential extraction analyses. Natural water(mine water, surface water and groundwater) and sediments were collected in six abandoned Au-Ag mine(Au-bearing quartz veins) areas. The contamination level of As in mine water of the Dongil(524${\mu}m$/L) is more higher than the tolerance level(500 ${\mu}m$/L) for waste water of mine area in Korea. Elevated levels of As in stream water were also found in the Dongil(range of 63.7∼117.6 ${\mu}m$/L.) and Gubong(range of 56.1∼62.9 ${\mu}m$/L) mine areas. Arsenic contamination levels in groundwater used by drinking water were more significant in the Dongil(11.3∼63.5 ${\mu}m$/L), Okdong(0.2∼68.9 ${\mu}m$/L) and Gubong(2.0∼101.0${\mu}m$/L) mine areas. Arsenate[As(V), $H_2AsO_4^-$] is more dominant than arsenite[As(III), $H_3AsO_3$] in water system of the most mine areas. The concentration ratios of As(III) to As(total), however, extend to the 95% in stream water of the Okdong mine area and 70∼82% in groundwater of the Okdong and Dongjung mine areas. As a study of seasonal variation in the water system, relatively high levels of As from the dongil mine area were found in April rather than in September. Sequential extraction analysis showed that As was predominantly present as coprecipitated with Fe hydroxides from sediment samples of the Dongjung and Gubong mine(35.9∼40.5%), which indicates its possibility of re-extraction and inducing elevated contamination of As in the reductive condition. In sediments from the Dongil, Okdong and Hwachon mine area, high percentage(55.2∼83.4%) of As sulfide form was found.

• Korean Journal of Environmental Agriculture
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• v.30 no.2
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• pp.153-159
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• 2011

BACKGROUND: This experiment was conducted to investigate the distribution and burden characteristics of heavy metal in the rainwater sampled at Taean area, in the middle part of Korea, from April 2002 to October 2003. METHODS AND RESULTS: The relationship between concentration of heavy metal and other chemical properties in the rainwaters was also evaluated. Chemical properties in the rainwater were various differences with raining periods and years. It appeared that a weighted average pH values of rainwater was ranged from 5.0 to 5.1. Heavy metal concentrations in the rainwater were ranked as Pb > Zn > Cu > Ni > As > Cr > Cd. As compared with heavy metal concentrations of rainwater in 2002, Cu, Pb, and Zn were higher than other elements in 2003. There were positive correlation between major ionic components, such as ${NH_4}^+$, $Ca^{2+}$, $Mg^{2+}$, $K^+$, $Na^+$, ${SO_4}^{2-}$ and ${NO_3}^-$, and As, Cd, Zn, Cr, and Ni concentrations in rainwater. For heavy metal distribution of rainwater, the order of average enrichment factor was Cd > Pb > As > Cu > Zn > Ni > Cr, and these were relatively higher than the natural components such as Fe, Mg and Ca. The monthly enrichment factor were relatively high, from August to October at Taean. The monthly amount of heavy metal precipitation was high in the rainy season from July to August because of great influence of rainfall. CONCLUSION(s): The results of this study suggest that the heavy metals(Cd, Pb, As, Cu, and Zn) of rainwater is strongly influenced by anthropogenic sources rather than natural sources.