• Journal of the Korean Society of Food Science and Nutrition
• /
• v.35 no.5
• /
• pp.588-593
• /
• 2006

This study was intended to observe possibility of which radiation technique can be used for oligopeptide production from pigskin collagen to reduce environmental pollution in processing and simplify the processing steps. Raw pigskin was ground using chopper, and then defatted in acetone cooled at $-20^{\circ}C$ freezer. Defatted dried pigskin was irradiated at 20, 40, 60, 100, 150, 200, 250, and 300 kGy using Co-60 gamma rays irradiator. With irradiation doses, the amount of soluble proteins increased, and the viscosity and turbidity of soluble proteins decreased, which could be clue of that irradiation degrade high molecular proteins directly. pH of soluble proteins from defatted pigskin increased in the sample above 150 kGy, and low molecular weight components (below 24 kDa) in SDS-PAGE increased. From gel permeation chromatography of the hydrolysates of pigskin irradiated at 300 kGy showed the major peak of 9,000, 8,200, 860, and 170 Da.

• Journal of Environmental Impact Assessment
• /
• v.27 no.2
• /
• pp.170-180
• /
• 2018

Highland fields are concentrated in the Jaun area of Hongcheong-gun, a large amount of sediments are discharged from the highland fields. The sediment runoff affect the turbidity and water quality of the Soyang Lake, furthermore adversely affect water supply source of the capital region. There are several kinds of BMPs(Best management practices) to decrease the sedimentrunoff from the highland fields. Although construction cost of multistage sedimentation basins is very high, there is no actual survey data for the removal efficiency of suspended sediments and water quality in our country. In this study, stormwaterinflow and outflow of the multistage sedimentation basins were surveyed, and the removal efficiency of nonpoint source pollutants were analyzed. The stormwater survey results fortwo rainfall events show thatremoval efficiencies of SS, BOD and TP loads in the multistage sedimentation basins are 35%~62%, 24%~55%, 35%~58%, respectively. Although the measured efficiencies of the basins were lower than the theoretical efficiency, the proper operation and management can improve the removal rate of the basins. Turbid water problem in the upper parts of the Soyang River can be managed effectively through the additional installation of multistage sedimentation basins.

• Korean Journal of Ecology and Environment
• /
• v.39 no.1 s.115
• /
• pp.52-61
• /
• 2006

The aim of this study was to analyze the seasonal patterns of zooplankton community dynamics in the lower Nakdong River (Mulgum, RK; river kilometer; 27 km from the estuarine barrage), with a Self-Organizing Map (SOM) based on weekly sampled data collected over ten years(1994 ${\sim}$ 2003). It is well known that zooplankton groups had important role in the food web of freshwater ecosystems, however, less attention has been paid to this group compared with other community constituents. A non-linear patterning algorithm of the SOM was applied to discover the relationship among river environments and zooplankton community dynamics. Limnological variables (water temperature, dissolved oxygen, pH , Secchi transparency, turbidity, chlorophyll a, discharge, etc.) were taken into account to implement patterning seasonal changes of zooplankton community structures (consisting of rotifers, cladocerans and copepods). The trained SOM model allocated zooplankton on the map plane with limnological parameters. Three zooplankton groups had high similarities to one another in their changing seasonal patterns, Among the limnological variables, water temporature was highly related to the zooplankton community dynamics (especially for cladocerans). The SOM model illustrated the suppression of zooplankton due to the increased river discharge, particularly in summer. Chlorophyll a concentrations were separated from zooplankton data set on the map plane, which would intimate the herbivorous activity of dominant grazers. This study introduces the zooplankton dynamics associated with limnological parameters using a nonlinear method, and the information will be useful for managing the river ecosystem, with respect to the food web interactions.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.33 no.10
• /
• pp.1685-1688
• /
• 2004

This study mechanically measured physical properties of jelly made by adding kappa carrageenan and agar-agar to the sipjeondaebo extract, varying the addition ratio. The sipjeondaebo extract used in the study showed 4.95 pH, 7.0 Brix$^{\circ}$, and high turbidity of more than 3.0 NTU. The sugar content was fixed at 25.2 Brix$^{\circ}$ when isomaltooligosaccharide was added in a 25-percent concentration. When the jelly was mechanically measured after it became hard in the refrigerator, the measurement results did not show any significant difference in cohesiveness between different addition ratios of agar-agar to kappa carrageenan. In the measurement of chewiness and gumminess, the jelly show a significantly decreasing tendency in both the two properties as the increase in the addition rate of agar-agar was made. Hardness was also measured lower as the more addition of agar-agar was made, and its the highest level was shown when there was the addition of kappa carrageenan only. Springiness was the highest when the ratio of kappa carrageenan to agar-agar was 0.7%:0.3%, while it was measured the lowest when agar-agar was added in a 1.0% concentration. In the measurement of the jelly's physical properties, the results showed the highest level of appearance when the ratio of kappa carrageenan to agar-agar was 0.7% but indicated that there was no significant difference in flavor. The overall Quality was evaluated to maintain the highest level at the kappa carrageenan to agar-agar ratio of 0.7%:0.3%, followed by a 0.5%:0.5% addition ratio.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.34 no.5
• /
• pp.478-482
• /
• 2001

This study was conducted to get a knowledge on food components of cuttle bone (CB) as a food resource. The yields and ash contents of CB were about $7.5\%$ on whole cuttle fish and about $90\%$ on dry basis, respectively, The contents of heavy metal might not invoke health risk in using food resource, The major mineral of CB was calcium as about $22\%$ in content. The yields, proximate compositions, heavy metal and mineral contents were not significantly different between domestic and imported CB. Judging from X-ray diffraction pattern, most of calcium in CB was present as a form of calcium carbonate (CC), and scanning electron micrograph showed irregular form. Buffering capacity of CB showed strongly at pH 7, and its pattern was the same as shown in that of CC, And CB solution showed a very high degree in turbidity comparing to that of CC solution. The solubility of CB was superior to that of CC, but inferior to those of calcium powders on the market, It was concluded from above results that CB could be effectively utilized as a calcium source.

• Applied Chemistry for Engineering
• /
• v.9 no.7
• /
• pp.1043-1046
• /
• 1998

Aluminium based inorganic flocculants are extensively used in this country in the removal of fine particles present in the raw water for the production of drinking water. These inorganic flocculants, however, have potential hazard of high residual aluminium ions in the treated waters, which is known to be one of the reasons of alzheimer's disease. Inorganic flocculants alone are sometimes incapable of treating water when there are excessive turbidity in the raw water sources due to flooding. A polyamine type polymeric flocculant has long been used to treat raw water in the drinking water production in the European countries and United State of America. The optimum reaction conditions such as mole ratio of epichlorohydrin(EPI) to dimethylamine(DMA), reaction temperature and time for each stage for the pilot scale preparation of polyamine from EPI-DMA was studied in this work. The variation of intrinsic viscosity and flocculating efficiency in the water treatment of the synthesized polyamines were evaluated. The residual materials after polymerization reaction were analyzed by gas chromatography to study the effect of variation of reaction conditions.

• Geomechanics and Engineering
• /
• v.8 no.6
• /
• pp.859-872
• /
• 2015

Pebble matrix filtration (PMF) is a water treatment technology that can remove suspended solids in highly turbid surface water during heavy storms. PMF typically uses sand and natural pebbles as filter media. Hand-made clay pebbles (balls) can be used as alternatives to natural pebbles in PMF treatment plants, where natural pebbles are not readily available. Since the high turbidity is a seasonal problem that occurs during heavy rains, the use of newly developed composite clay balls instead of pure clay balls have the advantage of removing other pollutants such as natural organic matter (NOM) during other times. Only the strength properties of composite clay balls are described here as the pollutant removal is beyond the scope of this paper. These new composite clay balls must be able to withstand dead and live loads under dry and saturated conditions in a filter assembly. Absence of a standard ball preparation process and expected strength properties of composite clay balls were the main reasons behind the present study. Five different raw materials from industry wastes: Red Mud (RM), Water Treatment Alum Sludge (S), Shredded Paper (SP), Saw Dust (SD), and Sugar Mulch (SM) were added to common clay brick mix (BM) in different proportions. In an effort to minimize costs, in this study clay balls were fired to $1100^{\circ}C$ at a local brick factory together with their bricks. A comprehensive experimental program was performed to evaluate crushing strength of composite hand-made clay balls, using uniaxial compression test to establish the best material combination on the basis of strength properties for designing sustainable filter media for water treatment plants. Performance at both construction and operating stages were considered by analyzing both strength properties under fully dry conditions and strength degradation after saturation in a water bath. The BM-75% as the main component produced optimum combination in terms of workability and strength. With the material combination of BM-75% and additives-25%, the use of Red Mud and water treatment sludge as additives produced the highest and lowest strength of composite clay balls, with a failure load of 5.4 kN and 1.4 kN respectively. However, this lower value of 1.4 kN is much higher than the effective load on each clay ball of 0.04 kN in a typical filter assembly (safety factor of 35), therefore, can still be used as a suitable filter material for enhanced pollutant removal.

• Journal of Korean Society of Environmental Engineers
• /
• v.39 no.4
• /
• pp.201-207
• /
• 2017

This study was conducted to investigate the characteristics of the stream current detector (SCD) and charge analyzing system (CAS), which are well known as the automatic coagulant dosage determination instruments. When the SCD system was used, the current charge value set at pH 9.3 could not be used as the coagulant dosage when the pH of the raw water decreased to 5.7, and the current charge value corresponding to pH 5.7 was required to be reset. In case of CAS system, polydadmac is stable as a cationic titrant when the pH of the raw water ranged 9.3 to 6.0. And it was effective to use polydadmac as a cationic titrant for high turbidity water. The current charge of polydadmac was almost constant between pH 5 and 11, however, the difference in charge of alum is six times in this pH range. Therefore, when the pH of the raw water was changed, it seems that the coagulant used in the actual water treatment plant was as a good cationic titrant.

• Korean Journal of Human Ecology
• /
• v.17 no.1
• /
• pp.151-158
• /
• 2008

This study examines the cooking quality, rheology, and sensory characteristics of ramyon noodles made from Korean wheat and arrowroot starch. The control was made from Australian standard wheat(ASW) and the sample was made from Korean wheat. The ratios of arrowwood starch in the sample group were 0%, 5%, 10%, 15%, 20%, 25%, and 30% respectively, and the result was as follows: the yield of the arrowwood starch was 18.8% and moisture level was 14.2%. The lightness(L), redness(a), and yellowness(b) of ASW were 92.07, 1.44, 10.22 respectively, whereas those of Korean wheat were 92.05, 1.55, 11.01, which means the two kinds of wheat showed very little difference in lightness, but Korean wheat had higher degrees of a and b than ASW. The color value of arrowroot starch is L 72.65, a 3.44, b 12.92, so it has a lower degree of lightness and higher degrees of a and b than two kinds of wheat. Dried ramyon displayed a lower degree of lightness and higher degrees of a and b than cooked ramyon, but the first decreased and a increased as we increased the ratio of arrowroot starch in it. The weight of dried ramyon did not show a significant difference among the groups. On the other hand, the weight, volume, water absorption, and the turbidity of cooked ramyon increased as we increased the amount of arrowroot starch in it. The maximum weight, solidity, and elasticity of the control group were greater than those of ramyon made from Korean wheat, but its brittleness was lower. The two groups showed the same degrees of hardness, adhesiveness, and cohesiveness. The maximum weight, solidity, and adhesiveness of the control group increased as we increased the amount of arrowroot starch in it, and the hardness and brittleness were great when the ratio of arrowroot starch was 20%; elasticity was greatest when the ratio of arrowroot starch was 15, 20, and 25%; its adhesiveness and cohesiveness did not depend on the amount of arrowroot starch in it. In the sensory characteristics evaluation, the items that showed significant differences include: appearance (p<0.01), color(p<0.01), smell(p<0.001), transparency(p<0.05), and overall acceptability(p<0.05). The ramyon earned the highest score in appearance when the ratios of arrowroot starch were 5%, 15%, and 20%. As for color and smell, it earned the highest score when it contained 20 and 25% of arrowroot starch. The transparency decreased as we increased the amount of arrowroot starch, and overall acceptability was highest when the ratio of arrowroot starch was 15%. There was a significant difference in overall acceptability between the control and the sample group. As for the loosing speed and chewiness, there was no significant difference between the two groups. When we look at the result of various tests to evaluate the cooking quality, rheology, and sensory characteristics of ramyon noodles, ramyons that contained 15 to 25% of arrowroot starch earned the high scores, and of these the one with 20% of arrowroot starch earned the highest score on all accounts.

• Journal of Korean Society of Environmental Engineers
• /
• v.27 no.10
• /
• pp.1035-1042
• /
• 2005

Granular Activated Carbon(GAC) is widely used in drinking water treatment. At S and B Water Treatment Plant, GAC is used in place of granular media in conventional rapid filters(GAC Filter-Adsorber) for removal of Disinfection By-products(DBPs). The primary focus of this study is on the performance of existing filter-adsorber, and their operation. It was found that F/A process removed turbidity as effective as sand system. The ratio of Hydrophobic DOM (HPO) and hydrophilic DOM (HPI) fraction in the raw water at S and B WTP was similar. Filter Adsorber presented earlier DOC breakthrough and steady state condition which was contributed by biodegradation during operation period. The removal efficiency of DBPs were used to evaluate the filter performance. The DBPs concentration of F/A treated water was below treatment goal level (THM < $80\;{\mu}g/L$, HAA < $60{\mu}g/L$). The removal efficiency of THM decreased rapidly during operation period. However, HAA were removed steadily regardless of the influent concentration of HAA. These results indicate that the removal of THM depend upon the adsorption mechanism while the removal of HAA depend upon biodegradation as well as adsorption. The decrease of adsorption capacity and characteristic value of GAC may be attributed to the effect of high organic loading, residual free chlorine, coagulants, manganese oxidants and frequently backwashing. This study has confirmed that Filter adsorber process can be considered as effective alternatives for the removal of DBPs, especially HAA.