• Analytical Science and Technology
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• v.13 no.3
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• pp.269-276
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• 2000

Chromatographic retention mechanism of seven benzoic acids in RPLC were investigated. Inorganic salt is pertinent for the measurement of dead time in benzoic acid. Logarthims of capacity factor (log k') and Hildebrand solubility parameter (${\delta}$) showed proportional relationship which imply the hydrophobic effect of the retention mechanism in RPLC. Enthalpies of solute transfer showed inverse proportion to temperature and organic modifier ratio of the mobile phase. It was found that the S value showed positive slope in plot of log k' vs. volume fraction of water in mobile phase. Free energy change increases with increasing organic volume fraction. The hydrophobicity index, ${\varphi}_0$(organic volume fraction) is inversely proportional to column temperature.

• Journal of Korea Water Resources Association
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• v.33 no.3
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• pp.299-306
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• 2000

Korea IS one of countries to be predicted short of water in the 21st century. The government has been investigating various alternatives to resolve the problems including construction of reservoirs. Freshwater retention techniques using boom and skirt system is one of them. It is very difficult to intake water in the estuaries of south and west coast of Korea because a big tide penetrates into an upstream river. Thus, means or retaining and keeping separate freshwater from seawater could potentially be helpful in solving the water supply problems. In this study, the proposed means to achieve freshwater retention is by use of floating boom and skirt systems. The hydraulic viability of these systems in taking advantage of natural stratification tendencies between the fresh and seawaters has been investigated through hydraulic experiments. It is found that freshwater retention capacity depends on skirt length and the opening beneath the skirt. The choice of skirt length IS very important to optimize freshwater storage because longer skirt lengths cause faster mixing and shorter lengths retain less volume. Results show that the freshwater retention volume generally increases as the length of the skirt increases. However, they show that water storage might be insufficient if skirts were either too long or too short.

• Journal of the Korean Institute of Landscape Architecture
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• v.26 no.2
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• pp.54-61
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• 1998

The subsurface environment of the root zone area can set the stae for "do or die" of the turfgrass plant. The good condition of the greens is verified by their physical properties. Therefore, this study was carried to evaluate on the existing green of Hwasan C.C. by undisturbed soil Core Anaysis. We completed the ISTRC SYSTEM BenchMarking of the undisturbed core samples taken from Green #1, Green #5, Green #9-"Best" area, and Green #9-"Stressed" area for the Hwasan C.C.. It was also our understanding that the greens were in "good" to "very good" conditioni. THe exception might be Green #9-"Stress" area, which was the stressed area. The stressed area was confined to a ridge across Green #9. The organic content test results comfirmed the development of organic layering in depth 0-2.5cm. For the amount of compaction in the upper root zones and te development of the green's respective organic layers, the infiltration rates were high in Green #1, Green #5, and Green #9 "Stressed" area. The depicted aerificaton hole might be the probable cause of the relatively high infiltraton rate. Green #9-"Best" area had a tested infiltration rate of 18.75cm/hr. Either this area had not been aerified, or the undisturbed sample did not contain a aerification cavity. The water retention capacity of the undisturbed samples was good. When the greens were first constructed, the original root zone mix had been relatively low water retention properties. And the bulk density and the porosity of the undisturbed samples were good. In the result, all the greens were similar except for the infiltration. Thus, we supposed that Green #9-"Stressed" area might be ainly influenced by the amount of irrigation water and the configuration of the green's surface. There had been a reduction in the amount of irrigation water as the water retention capacity in the greens was promoted. Especially, it had gradually become more of a problem as the green had matured in Green #9-"Stressed" area. Because Green #9-"Stressed" area was a ridge area. The reduction in the amount of irrigation water might be the probable cause of the stress in Green #9-"Stressed" area. Our final observation related to the soil texture and the particle size distribution of the sand. Though and sand contant of all the tested greens were good, the gravel content of them exceeded ISTRC Guidelines. In particle size distribution of the sand, the very coarse and the coarse content of all the tested greens exceeded, but the rest was insufficient. The stability is a function of the material retained on the 0.25mm mesh screen. But, the content of all the tested greens was very insufficient. Though all the greens was serviceable, the coarse root zone sands, such as the sand in the tested greens, tended to be "unstable". Thus, we recommend using a topdressing/aerification sand which should be more in line with ISTRC/USGA Guidelines.;unstable". Thus, we recommend using a topdressing/aerification sand which should be more in line with ISTRC/USGA Guidelines.ines.

• Food Science of Animal Resources
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• v.39 no.4
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• pp.623-631
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• 2019

Tetramethylpyrazine (TMP), an alkaloid rich in Ligusticum wallichii and fermented products, possesses multiple pharmacological activities in antioxidant, antiinflammatory, and antibacterial. This study aimed to investigate the effect of TMP (15 mg/L) on the physicochemical and gelation properties of rabbit myofibrillar proteins (MPs) with/without oxidative stress. Results showed that compared to the control, oxidative stress to MPs decreased free thiol content, gel yield, whiteness, water-holding capacity, bounder water, immobilized water, and endogenous tryptophan fluorescence intensity, but increased surface hydrophobicity, dityrosine content, and free water content (p<0.01). Without oxidative stress, MPs treated with TMP increased free thiol content, whiteness, and bound water, but decreased dityrosine content and free water (p<0.05). Under oxidative conditions, all parameters were conversely affected by TMP (p<0.01). The results suggest that TMP can be an antioxidant to decrease the concern on oxidative deterioration during meat processing and storage by improving the oxidative stability, water retention, and gel forming property of rabbit MPs.

• Nuclear Engineering and Technology
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• v.41 no.8
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• pp.1005-1014
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• 2009

The Dual Unit Optimizer 2000 MWe (DUO2000) is put forward as a new design concept for large power nuclear plants to cope with economic and safety challenges facing the $21^{st}$ century green and sustainable energy industry. DUO2000 is home to two nuclear steam supply systems (NSSSs) of the Optimized Power Reactor 1000 MWe (OPR1000)-like pressurized water reactor (PWR) in single containment so as to double the capacity of the plant. The idea behind DUO may as well be extended to combining any number of NSSSs of PWRs or pressurized heavy water reactors (PHWRs), or even boiling water reactors (BWRs). Once proven in water reactors, the technology may even be expanded to gas cooled, liquid metal cooled, and molten salt cooled reactors. With its in-vessel retention external reactor vessel cooling (IVR-ERVC) as severe accident management strategy, DUO can not only put the single most querulous PWR safety issue to an end, but also pave the way to very promising large power capacity while dispensing with the huge redesigning cost for Generation III+ nuclear systems. Five prototypes are presented for the DUO2000, and their respective advantages and drawbacks are considered. The strengths include, but are not necessarily limited to, reducing the cost of construction by decreasing the number of containment buildings from two to one, minimizing the cost of NSSS and control systems by sharing between the dual units, and lessening the maintenance cost by uniting the NSSS, just to name the few. The latent threats are discussed as well.

• Journal of Korean Society of Forest Science
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• v.90 no.4
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• pp.450-457
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• 2001

This study aimed to clarify the influencing site factors of the mesopore ratio on a pore geometry of surface soil in deciduous stands as an index of the water retention capacity. Fifteen factors including site conditions and soil properties were analyzed by spss/pc+ for the data collected during March to October of 1994. The factors influencing the mesopore ratio(pF2.7) on the surface soil were as follows; tree height, under vegetation coverage and organic matter contents of soil. And influencing factor on the ratio of mesopore in the soil surface was correlated with surface soil hardness shows high negative significance. Also, multiple regression equations for mesopore ratios of surface soil hardness, organic matter contents of soils show high significance($R^2=0.84$). In deciduous stands, it is effective in promoting development on the ratio of mesopore that forest practice for enhancing of the water resource retention capacity should be carried out when the under vegetation coverage rates of stands are maintained from 30 to 80 percentages.

• Journal of Korean Society of Forest Science
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• v.90 no.3
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• pp.314-323
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• 2001

This study aimed to clarify the influencing factors of mesopore ratio on a pore geometry of surface soil in coniferous stands as an index of the water retention capacity. Twenty three factors including site conditions and soil properties were analyzed by spss/pc + for the data collected during March to October of 1993. The factors influencing the mesopore ratio(pF2.7) on the surface soil were as follows; macropore ratio(pF1.6), slope, crown-cover rates, thickness of F layer, organic matter contents, and the growing stock. And influencing factor on the ratio of mesopore in the soil surface was correlated with percentage of amount of clay, soil surface, A and B horizon soil hardness shows high negative significance. Also, multiple regression equations for mesopore ratios of surface soil and surface soil hardness, clear length, growing stock, B horizon of soil hardness, organic matter contents show high significance($R^2$; 0.80). In coniferous stands, it is effective in promoting development on the ratio of mesopore that forest practice for enhancing of the water resource retention capacity should be carried out when the crown-cover rates of stands are more than 80 percentages.

• Korean Journal of Soil Science and Fertilizer
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• v.35 no.4
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• pp.197-206
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• 2002

Volumetric soil water contents through a soil profile were monitored to identify the effects of tillage systems and soil physico-chemical characteristic on soil water movement from the soil profile. Water content profiles under no tillage (NT) and conventional tillage (CT) practices were compared at two commercial farms in central Illinois from 1992 through 1994, using neutron-scattering techniques in weekly intervals during each growing season. The volumetric water content of surface soil layers was affected more by tillage systems and rainfall amounts, whereas that of the subsoil layers was more strongly affected by soil types. Soil water percolated faster through Saybrook and Catlin soils than through Drummer, Flanagan, and Ipava soils because Saybrook and Catlin soils have lower clay content and water-retention capacity and higher permeability than Drummer, Flanagan, and Ipava soils. Increased soil organic matter (SOM) in Drummer, Flanagan, and Ipava soils would be attributable to the higher soil water retention than other soil types. Soil water contents in the corn root zone were consistently higher under CT plots than under NT plots.

• Korean Journal of Food Science and Technology
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• v.3 no.1
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• pp.48-51
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• 1971

The raw surf clam meat was pretreated with BHA, EDTA or $NaHSO_3$. The pretreated meat was chopped with chopper, and spread the chopped meat on nylon net, and then dehydrated with cabinet type hot air dryer. In the surf clam meat flake process, the pretreating and the copping steps prior to final dehydration improved the pigment retention and texture of the products. The chopping steps prior to dehydration reduced the dehydration time of surf clam meat. The BHA treatment prior to dehydration of mashed surf clam meat had an outstanding effect on the pigment retention during a process of dehydration and storage. The surf dam meat flakes reabsorbed water more rapidly about two times than the dehydrated natural surf clam meat products. The surf clam meat flakes stored for three months in the dark place showed less pigment loss than the exposed ones, and the former reabsorbed water more rapidly than the latter.

• Journal of the Korean Society of Food Science and Nutrition
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• v.2 no.1
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• pp.55-59
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• 1973

This experiment was carried out to improve on the simple and conventional processing method by studying the characteristics of poultry meat. For the experiment, 20 hens culled and 20 broilers were slaughtered and divided into the following five groups; whole carcass, skinned carcass, debonned carcass, thigh muscle and breast muscle. Each group was ground by the super grinding machine. The results tobtained are summarized as follows; (1) The percentage of the ready-to-cook of cull hens and broilers was $64.32{\pm}2.11,\;67.96{\pm}1.16$, and of the water uptake, $105.43{\pm}1.9,\;104.13{\pm}0.2$, respectively. (2) In the chemical composition, broiler meat showed high moisture content and a little low fat content, as compared with cull hen meat. By groups, whole carcass ground meat contained lower maisture content, and higher fat and ash content than thigh muscle and breast muscle. (3) Thigh muscle and breast muscle group was higher than the other and whole carcass group was lower for the relative WHC and water retention.(4) The higher temperature the higher cooking loss percentage in all groups, and whole carcass group was the highest cooking loss percentage among the all groups.(5) The significant difference was little observed for the relative WHC, water retention and cooking loss percentage by groups between cull hen and Broiler.