• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.4
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• pp.500-509
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• 1993

Pectins present in the primary cell walls and middle lamellae of plant cell walls are extracted by water, cheating agents, acid or alkali solutions. However, some neutral contaminating components are extracted in conjunction with pectins during the extraction process. Thus, the accurate characterization of physi-cochemical properties of pectins necessitates to get rid of the impurities. In this review, dialysis, alcohol precipitation, ion exchange chromatography and metal precipitation were compared as procedures to purify the pectin extracts. In addition, the chemical methods to analyze pectins are discussed in terms of three major chemical constituents, i.e., anhydrogalacturonic acid, methoxyl groups and neutral sugars.

• Resources Recycling
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• v.11 no.5
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• pp.21-23
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• 2002

A new process based on the co-precipitation method was developed fer removing harmful impurities during Mn-Zn ferrite production such as $SiO_2$ and P from waste pickle liquor. By this process a final result of less than 100 ppm of $SiO_2$ and less than 10 ppm of P content in the ferric oxide is easily attained. Though Ca cannot be removed by this process, water rinsing of the ferric oxide is effective fer reducing Ca content to less than 100 pm. For further purification, the origins of each impurity must be investigated and then taken away.

• The Korean Journal of Food And Nutrition
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• v.13 no.2
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• pp.146-151
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• 2000

To evaluate anticaries and antiinflammation of Aloe vera peel, antimicrobial substances were extracted from Aloe vera peel and identified. The antimicrobial active substances of water extract were successfully purified with solvent fractionation, silica gel column chromatography, preparative thin layer chromatography and UV spectrophotometer. Two purified active substances were identified as aloe-emodin and barbaloin by Mass Spectrometer, 1H-NMR and FT-IR.

• KCID journal
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• v.21 no.1
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• pp.55-63
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• 2014

A sedimentation basin for agricultural water quality improvement was researched to analyze the water quality purification characteristics. The sedimentation basin constructed at the inlet of Gamdon reservoir in Muan-gun, Jeollanam-do was selected as the research field of this study. The surface area of the sedimentation basin is $34,000m^2$, volume is $122,000m^3$, and hydraulic retention time is 0.3hr~7.3day. The average influent loading of SS was 156.6kg-SS/d, and the effluent loading was 67.5kg-SS/d with the average removal rate of 56.9%. The average influent loadings of BOD and COD were 33.0kg-BOD/d and 60.3kg-COD/d respectively, and the effluent loadings were 26.4kg-BOD/d and 48.6kg-COD/d with the average removal rate of 20.1% and 19.3% respectively. Therefore, the results of this study show that a sedimentation basin can purify SS and organic matters. The average influent loadings of T-N and T-P were 28.7kg-TN/d and 2.97kg-TP/d respectively, and the effluent loadings were 16.3kg-TN/d and 1.41kg-TP/d with the average removal rate of 43.0% and 52.6% respectively. In conclusion, the overall results of this study show that a sedimentation basin is a feasible alternative to purify organic matters and nutrients.

• Journal of Korean Society on Water Environment
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• v.22 no.6
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• pp.1038-1044
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• 2006

The floating island was investigated in order to make a purification of lake water quality with the uptake of nutrients, the prevention of algae growth and the supply of habitat for aquatic plants. Although the concentrations of organics and nutrients inside facility were shown higher than outside, the quantitative analysis was not attainable. Nitrogen uptakes by Cattail, Phragmites japonica, Reed and Wild rice were shown 48.2, 98.0, 111.1 and $72.0g/m^2{\cdot}year$, respectively, and in the case of phosphorus they were 3.2, 8.3, 6.1 and $4.6g/m^2{\cdot}year$, respectively. Considering total floating areas of $2,560m^2$, the nitrogen uptake is totally estimated to $210.7kg/m^2{\cdot}year$ and $14.2kg/m^2{\cdot}year$ for the phosphorus uptake. In order to promote the spread of floating island, the selection of aquatic plants, the control of growth rate properly and the method of quantitative analysis for the purification of water quality and the application to the stream water should be thoroughly surveyed from all angles prior to the application.

• Magazine of the Korean Society of Agricultural Engineers
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• v.42 no.4
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• pp.87-95
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• 2000

A vegetation purification system was applied to improve water quality of Masan Reservoir in Korea, which was composed of constructed wetlands in series. Five different kinds of macrophytes were planted in each wetland. The system was operated with the condition of low concentrations and high hydraulic loadings. Removal efficiencies(%) of chemical oxygen demand(COD) , total nitrogen(T-N) and total phosphorus(T-P) in this system were 9.0, 12.8, 20.1% , respectively. and removal rates(g/$m^2$/d) were 1.9(COD), 0.34(T-N) and 0.05(T-P) . Comparing this system with other wetlands operated at low hydraulic loadings, average removal efficiencies were low but removal rates were relatively high. Accordingly, this system could be applied to imporve reservoir water quality, because removal rates are more important than removal efficiencies in case of reservoir water quality improvement . However, the removal efficiencies and rates of this system are less than those of the hydroponic biofilter method which is a kind of a constructed wetland and utilize root zones of emergent macrophytes for trapping pollutants. Therefore, it is recommended that this system should be modified to utilize root zones of emergent macrophytes enough to improve reservoir water quality more efficiently.

• Membrane and Water Treatment
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• v.8 no.2
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• pp.137-147
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• 2017

A water treatment utility in South Korea operates a large system of pressurized hollow fiber membrane (PHFM) modules. The optimal selection of membrane module for the full scale plant was critical issue and carried out using Risk-based Life Cycle Cost (RbLCC) analysis based on the historical data of operation and maintenance. The RbLCC analysis was used in the process of decision-making for replacing aged modules. The initial purchasing cost and the value at risk during operation were considered together. The failure of modules occurs stochastically depending on the physical deterioration with usage over time. The life span of module was used as a factor for the failure of Poisson's probability model, which was used to obtain the probability of failure during the operation. The RbLCC was calculated by combining the initial cost and the value at risk without its warranty term. Additionally, the properties of membrane were considered to select the optimum product. Results showed that the module's life span in the system was ten years (120 month) with safety factor. The optimum product was selected from six candidates membrane for a full scale water treatment facility. This method could be used to make the optimum and rational decision for the operation of membrane water purification facility.

• Nuclear Engineering and Technology
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• v.23 no.3
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• pp.299-305
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• 1991

Corrosive environment may be generated within steam generators from condenser cooling water in-leakage. Theoretical analysis of the accumulation of chloride as a sea water impurity is being carried out for the condenser cooling water used at YGN-1,2 nuclear power stations. Calculations have shown that highly concentrated chloride solution would be produced within the steam generators in the case of sea water in-leakage. Maximum allowable design condenser leak rate(0.5 gpm) leads chloride concentration of 2.3 ppm at steam generetor and 0.6 ppm at hotwell with the maximum blowdown rate and condensate purification. Concentration factor at steam generator is dependent only on both blowdoum rate and condensate purification efficiency as follows, Concentration Factor（equation omitted）(B$\neq$O) Blowdown and condensate purification are evaluated as the only effective measures to remove impurities from the secondary systems.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.757-760
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• 2008

Recently, improvements in the standard of living in industrial area require establishment of a convenient residential environment in order to enhance the quality of living, To achieve such an environment, it is necessary to effectively reduce or prevent various environmental problems occurring in and around residential areas. In this study, We focused on the water-purification properties of concrete using effective micro-organisms. Such as SS, BOD, COD, T-P, T-N. The ability of the removal of SS, T-P, T-N in the test water is superior to concrete using effective micro-organisms. As a result, concrete using effective micro-organisms has sufficient performance of water-purification.

• Applied Chemistry for Engineering
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• v.22 no.3
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• pp.332-335
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• 2011

As our interests in eco-friendly materials have been significantly increased, the utilization of porous zeolite concrete that has structural functionality and permeability has been increased. In this paper, the mixture of porous concrete and zeolite, which can be used as multirole boulders, was investigated for the suitability of an environment-friendly product by evaluating of the water purification ability. The contamination removal rates of BOD, TOC, T-N, and T-P in stagnant water tank were 70.6, 67.0, 57.7, and 50.6%, respectively. Also for the non-point source pollution with the inflow and the outflow, the removal rates of Zn, Pb, BOD, and COD were 99.9, 90.0, 69.2, and 33.5%, respectively. The performance of the heavy metal contamination removal for the porous zeolite showed better than that of stagnant system. Therefore, it is expected that the installation of the porous zeolite concrete can play a role as an eco-friendly products by its high contamination removal.