• Journal of Ecology and Environment
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• v.32 no.4
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• pp.295-304
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• 2009

To understand the properties of soil in Dokdo, we collected soil samples from 12 locations on Seodo and 23 locations on Dongdo, in Dokdo of Gyeongsangbuk-do Province in 2007-2008 and analyzed the soil's physical and chemical characteristics. Sand comprises the largest component (49.37%) of Dokdo soil, followed by silt (40.70%) and clay (9.93%). The soil structure consists mostly of sand loam, followed by loam and silt loam. The pH level of soils from Dokdo varied dramatically among sampling sites and seasons, ranging from 3.36 to 8.02. The total ion content of Dokdo soil also varies greatly among survey places and periods, but in general the total ion content was high in summer when vegetation develops, and low in spring. The exchangeable cation contents of the soil showed low levels in samples where the soil pH was low, including habitats dominated by Agropyron tsukushiense var. transiens and Echinochloa crus-galli, whereas the exchangeable cation contents were high where the organic contents were high, as in habitats dominated by Liriope platyphylla and Artemisia japonica subsp. littoricola. Soil N contents varied greatly among survey sites and higher N contents were found in soil inhabited by Chenopodiaceous plants than in habitats inhabited by other plants. The substantial differences in phosphorus contents among sites were related to excrement of black-tailed gulls. To understand the basic physical and chemical features of the soil on Dokdo, it will be necessary to conduct seasonal and long-term research on soil pH, ion contents, organic contents, N and P, as well as obtaining precise data from samples collected at different depths.

• Animal Bioscience
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• v.37 no.6
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• pp.1077-1084
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• 2024

Objective: The present work was conducted to evaluate suitable variables and develop prediction equations using chemical composition and physical characteristics for estimating standardized ileal digestibility (SID) of lysine (Lys) in full-fat soybeans (FFSB). Methods: The chemical composition and physical characteristics were determined including trypsin inhibitor activity (TIA), urease activity (UA), protein solubility in 0.2% potassium hydroxide (KOH), protein dispersibility index (PDI), lysine to crude protein ratio (Lys:CP), reactive Lys:CP ratio, neutral detergent fiber, neutral detergent insoluble nitrogen (NDIN), acid detergent insoluble nitrogen (ADIN), acid detergent fiber, L* (lightness), and a* (redness). Pearson's correlation (r) was computed, and the relationship between variables was determined by linear or quadratic regression. Stepwise multiple regression was performed to develop prediction equations for SID of Lys. Results: Negative correlations (p<0.01) between SID of Lys and protein quality indicators were observed for TIA (r = -0.80), PDI (r = -0.80), and UA (r = -0.76). The SID of Lys also showed a quadratic response (p<0.01) to UA, NDIN, TIA, L*, KOH, a* and Lys:CP. The best-fit model for predicting SID of Lys in FFSB included TIA, UA, NDIN, and ADIN, resulting in the highest coefficient of determination (R² = 0.94). Conclusion: Quadratic regression with one variable indicated the high accuracy for UA, NDIN, TIA, and PDI. The multiple linear regression including TIA, UA, NDIN, and ADIN is an alternative model used to predict SID of Lys in FFSB to improve the accuracy. Therefore, multiple indicators are warranted to assess either insufficient or excessive heat treatment accurately, which can be employed by the feed industry as measures for quality control purposes to predict SID of Lys in FFSB.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.5
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• pp.819-825
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• 2000

The physico-chemical characteristics and the combustion activities of a waste automotive catalyst were carried out in this study. The physico-chemical characteristics of waste automotive catalyst was examined by EA(Elemental analysis), ICP-AES (Inductively coupled plasma-atomic emission spectrophotometer), and XRD(X-ray diffraction) analysis. Carbon deposit amount was higher in front brick than rear brick of catalyst, and increased with mileage. The content of Pt. Pd and Rh in waste automotive catalyst was different from the car manufacturing company. The combustion activities of waste automotive catalyst were investigated for acetaldehyde as a model VOC in a fixed bed reactor at atmospheric pressure. The catalytic activity of rear brick for acetaldehyde combustion was better than front brick of waste automotive catalyst. The catalytic activity of waste automotive catalyst for acetaldehyde combustion decreased with mileage. The linear relationship between catalytic activity and mileage was negative and has a very excellent correlation. Finally, the waste automotive catalyst has a good catalytic activity for acetaldehyde combustion. and can be used to control of small emission source.

• Asian Journal of Turfgrass Science
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• v.5 no.2
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• pp.81-86
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• 1991

The sludge, a waste of brewery industries, was examined for potentials as a natural organic fertilizer (or soil conditioner) for lawn. Trial products were measured for changes of physical, chemical properties in laboratory and seed germination and seedling growth in green house were also tested. The results are as the following:1The sludge from distilled liquor brewery contained high quantity of organic matter which had proper physical and chemical properties for lawn fertilizer (natural organic fertilizer, soil conditioner, top-dressing mix) . It showed good characteristics in handling and capabilities to be developed as commercial products for golf courses. 2.Sludge from beer company needs proper treatment to improve physical properties for futher degradiation. It is because aggregation of the sludge particles prevented microbial activities and changing to soluble form. 3.Green carbon can be used as carbon source for organic fertilizer production using brewery sludge, but it should not contain wood extract which inhibit seed germination and seedling growth.

• Korean Journal of Food Science and Technology
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• v.33 no.2
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• pp.245-251
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• 2001

This research was conducted to study the changes in physical characteristics of mushrooms (Agaricus bisporus) as influenced by drying methods. Samples were dried using either hot air drying, vacuum drying, or freeze drying and changes in the color, browning index, hardness and rehydration rate were evaluated by response surface methodology. Hot air drying resulted in the fastest drying of sample as compared to other methods. The rate of drying was most affected by the environmental temperature rather than air velocity or vacuum pressure. The overall color difference increased as the temperature and air velocity increased. The overall color changes of the freeze dried samples were minimal as compared to those of fresh mushrooms. The hot air dried samples showed the greatest changes in the overall color, browning index as well as hardness. The freeze dried samples showed the best rehydration characteristic and maintained the best overall quality after drying.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2009.04a
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• pp.23-28
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• 2009

The purpose of this study was to improve not only wet-end performances but also paper characteristics by the modification of various factors like molecular design and ionic characteristics of polyacrylamides First of all physical characteristics were observed after modify molecular design of the cationic polyacrylamides to linear, branched and cross-linked. In addition it was found analysis method to confirm branch degree of cationic polyacrylamides to combine ionic titration characteristics and spectroscopic behavior, After application of these structure modified polyacrylamides to the multiple retention systems with inorganic microparticles, it was found adjusting of branch degree of polyacrylamides was very important to optimize wet-end improvement. Second, After polymerization of amphoteric polyacrylamide to have both of cationic and anionic functional group in the polymer, we observed not only physical characteristics but also wet-end improvement to apply recycled pulp and found that the improvement of solution stability to prevent hydrolysis and increase of ash retention dramatically to compare traditional cationic polyacrylamide retention aid, Finally, After polymerization of anionic polyacrylamide, we observed not only wet-end improvement but also paper characteristics to apply preflocculation of PCC and it was found the improvements of flocculation efficiency, retention, ash retention, optical properties of the paper and bursting strength to compare traditional preflocculant of cationic polyacrylamide.

• Korea-Australia Rheology Journal
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• v.11 no.4
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• pp.313-320
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• 1999

The difficulties involved in measuring rheological characteristics of complex fluids are discussed. Possible measurement errors, related to the complex nature of the sample, are reviewed. They are explained in terms of the various physical and chemical mechanisms that can cause them. This leads to possible strategies and techniques for avoiding measurement errors and for obtaining useful structural information from rheological experiments on complex materials. Finally, future evolutions in rheometry are discussed.

• Bulletin of the Korean Chemical Society
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• v.16 no.11
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• pp.1046-1056
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• 1995

A topological theory has been introduced to evaluate the degree of complexation and the viscosity of polymer complexes by extending the theory of Iliopoulos and Audebert for aqueous polymer solutions. The previous theory of Iliopoulos and Audebert has offered only a semiquantitative theoretical model for polymer complex systems, whereas our present work gives a general theoretical model applicable to all the polymer complex systems. Their theories considered only the physical property term caused by the displacement of complexed points between polymer solute chains, while our theory deals with all the physical effects, caused by the displacement of complexed points entangled points in polymer solute chains. There have been predicted the characteristics of physical properties from the expression. It is exposed that the predictive values show good agreement with the experimental data for polymer complexes.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2008.04a
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• pp.93-94
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• 2008

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1999.12a
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• pp.509-515
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• 1999