• Journal of Energy Engineering
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• v.19 no.4
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• pp.215-220
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• 2010

Hydrogen is a clean and efficient energy source and is expected to take an important role in future energy demand. A possibly good route to produce hydrogen is by using biomass and organic wastes as a source through thermo-chemical conversion technology. In this study, pyrolysis of wood Pellet(Oregon pine) has been carried out in batch type fixed-bed reactor in $N_2$ atmosphere during 20 minutes to determine the optimum hydrogen generating conditions. At the influence of temperature, hydrogen yield was increased with increasing temperature. For the influence of Steam/Biomass Ratio(SBR), hydrogen yield was increased by steam addition at low temperature condition. However, effect of steam addition was insignificant over at SBR = 1. The hydrogen yield was increased with increasing SBR at high temperature condition. From result of $H_2$/CO and $H_2/CH_4$ ratio, dominant reaction was steam reforming in this experimental condition. The optimum condition for hydrogen production was determined as follows: $H_2$ yield = 38.3 vol.% (56.01 L/min kg) at $900^{\circ}C$, SBR=3.

• Korean Journal of Ecology and Environment
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• v.33 no.3 s.91
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• pp.213-221
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• 2000

Seasonal oxygen content and deficit rates were evaluated from 17 sites of Taechung Reservoir during 1993${\sim}$1994. In 1993, river inflows peaked during the monsoon in July${\sim}$August and disrupted thermal stratification and anoxic layers in the headwaters, thereby confining the anoxia to the mid-lake and downlake reach. The volume of anoxic water with < 4 mg/l DO comprised only < 10% of the total lake volume in this period. In contrast, during monsoon 1994, 85% of total lake volume was subject to hypoxic conditions with oxygen concentrations < 30% saturation, resulting in massive fishkills (Hypomesus olidus). Relative areal oxygen deficit (RAOD) was -0.024mg O$_{2}$cm$^{-2}$d$^{-1}$ during monsoon 1993, whereas it rapidly decreased at the rate of 0.080mg O$_{2}$cm$^{-2}$d$^{-1}$ during monsoon 1994. Anoxic factor (AF) showed a same interannual pattern as the RAOD and was greater >50 d in 1994 (76.5 d) than 1993 (21.3 d). Thus, the reservoir showed a river-characteristics (6${\sim}$11 mg/l DO) in 1993 while lacustrine conditions (<4mg/l DO) dominated in 1994. Regression analysis showed that the variation of summer DO was mostly determined (R$^{2}$=0.99, p<0.0001) by inflow. These findings suggest that the primary factor regulating the oxygen content in this system during summer is an intensity of the monsoon rain.

• Korean Journal of Food Science and Technology
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• v.23 no.2
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• pp.235-240
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• 1991

Starch phosphates were prepared from the corn starch mixed with 2% sodium tripolyphosphate by twin-screw extruder with a feed rate of 20 kg/hr and an extrusion temperature of $130^{\circ}C$, and the effects of extrusion variables on the physicochemical properties (target parameters) of starch phosphates were investigated. Interrelations of system parameters (specific mechanical energy and extrudate moisture) and rheological properities of starch was analyzed by using the response surface analysis. Degree of substitution (DS) was increased with increasing the feed moisture, and showed the maximum value at the screw of near 250 rpm, Degree of gelatinization was proportionally increased with increasing the screw speed and decreasing the feed moisture. Apparent viscosity of the paste was increased with increasing the feed moisture, but it was not significantly affected by the screw speed. It was found by scanning electron microscopy that the starch microgranules were much more degradaded, and as consequent result, the intrinsic viscosity was decreased, whereas, water solubility index was increased. The rate of retrogradation of the gels was retarded with increasing DS and decreasing viscosity.

• Korean journal of food and cookery science
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• v.3 no.1
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• pp.71-77
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• 1987

This study was to investigate the synergistic taste effect between monosodium glutamate(MSG) and 5'-ribonucleotides consisted of disodium 5'-inosinate (IMP) and 5'-guanylate (GMP) as 1:1 ratio. Solvent was distilled water. Sensory evaluation with 10 panelists was performed by using ratio scaling method (magnitude estimation). The results were as follows: 1) Taste intensities were increased, as nucleotides content to MSG increased. 2) Multiple regression analyses were carried out with the taste intensity data as a function of nucleotides content at three concentrations of seasonings, 0.025%, 0.05% and 0.1%. 3) Predicted taste intensities ($Y_P$) were calculated from the regression equation. Also taste intensity ratios ($Y_{TR}$)-$Y_{TR}$=$Y_P$/taste intensity of MSG only-were calculated. 4) The taste intensity ratios ($Y_{TR}$) at three concentrations of seasonings in the same nucleotides contents showed about the same. Therefore, instead of above regression equations, only one multiple regression equation expressing $Y_P$ of nucleotides seasonings could be determined, as functions of nucleotides content and seasoning concentration.

• Journal of Wetlands Research
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• v.14 no.2
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• pp.265-275
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• 2012

As climate change is becoming a growing concern and the importance of water management is increasing, the retention of carbon and nutrients in wetland soils including inland and coastal area has become important. In this study, retention characteristics of organic matter and nutrients of coastal sediment and soils in different types of wetlands such as constructed wetland, natural (inland marsh, estuary, tidal flat) wetlands were investigated. A correlation analysis was also performed to understand the relationship among organic matter properties, nutrient concentrations and soil texture of wetland soils. The degree of retention of organic matter and nitrogen in wetland soils varied with the wetland type. Inland wetlands retain more nitrogen than estuary or coastal wetlands, and natural wetlands retain more organic matter and nitrogen than constructed ones. Coastal sediments in a bay area where seawater circulation is restricted have more nutrients than those in estuary or tidal flats where seawater circulates well. The results showed that the sediment chemical oxygen demand has a high correlation with the total organic carbon and the total nitrogen in the studied area.

• Applied Biological Chemistry
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• v.35 no.1
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• pp.42-50
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• 1992

We conducted screening on Chinese medicinal herbs to examine their anti-complementary activity by hemolytic complementary assay $(TCH_{50})$. Among 55 kinds of herbs, several herbs showed relatively potent anti-complementary activity which decreased $TCH_{50}$, more than 70% in comparison with control. Then, hot water extracts of the following herbs, Curcuma aromatica, Areca catechu, Gleditsiae spina, Euonymus alata, Acanthopanax senticous. Lonicera japonica, Aconitum carmichaeli, Curcuma zedoaria and Cinnamoum cassia, which were shown relatively potent anti-complementary activity were partially purified and analyzed their chemical properties. These activities were resistant to digestion with pronase but decreased by treatment with $NaIO_4$. These results may indicate that the complement activating ability in their herbs is due to polysaccharide. Furthermore, the anti-complementary activity of Areca catechu which was showed the most potent activity, was reduced partially in the absence of the $Ca^{++}\;ion$. After incubation of the normal human serum with partially purified polysaccharide of A. catechu in the absence of $Ca^{++}\;ion$, a cleavage of C3 in the serum was found to have occurred through immunoelectrophoresis using rabbit anti-human C3 serum. These results indicate that the mode of complement activation by polysaccharide of A. catechu is via both the alternative and classical pathway.

• Textile Coloration and Finishing
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• v.5 no.4
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• pp.29-41
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• 1993

In order to surface Hydrophobilization of Poly(ethylene terephthalate) (PET) fiber samples were treated in the atmosphere of CF$_{4}$ or $C_{2}$F$_{6}$glow discharge. The sample used in this study was PET film which is 75$\mu$m thick made by Teijin, O-Type(Japan). The cleaned samples were placed in plasma reactor made of pyrex glass cylinder, and plasma processing was carried out by glow discharge of CF$_{4}$ or $C_{2}$F$_{6}$ gas, being continuously fed by gas flow and continuously pumped out by a vacuum system. Electric power source for generate plasma state was sustained alternating current(60Hz) and voltage was sustained 600 volt. The duration of plasma treatment varied from 15 to 120 seconds except special case, the monomer gase pressure varied from 0.02 to 0.3 Torr and power range was 10 to 90 watts. The hydrophobic features of changed PET surface were evaluated by contact angle measurement and surface chemical characteristics were analyzed by ESCA. Results can be summerized as follows. 1. The most favorable setting position of substrate was the center area between the two electrodes. 2. $C_{2}$F$_{6}$ discharge current was lower than that of CF$_{4}$ when same voltage was sustained. Treated efficiency between CF$_{4}$ and $C_{2}$F$_{6}$ did not revealed significant differences under same electric power(wattage). 3. When monomer pressure is very low below 0.02 torr, as though substrate is exposed to CF$_{4}$ or $C_{2}$F$_{6}$ plasma, it tend to be hydrophilic through a little of fluorine bond and a great deal of oxidizing reaction. 4. There brought good hydrophobilization when monomer pressure was more 0.1 torr and duration of glow discharge treatment was over 45 seconds. When monomer pressure was too high, discharge current became low. Although prolong the duration, there was no more high hydrophobilization. 5. According to ESCA analysis, there were a little CF bond and a prevailing CF$_{2}$ bond in CF$_{4}$-treated substrate. There were CF$_{3}$, a little CF and a prevailing CF$_{2}$ bond in $C_{2}$F$_{6}$-treated substrate.d substrate.

• Korean Journal of Environmental Biology
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• v.32 no.4
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• pp.319-326
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• 2014

Fish community was investigated in eutrophic Jeondae agricultural reservoir from April to November 2012. The food web structure of major fish species of Jeondae reservoir showed that due to serious organic pollution, the hyper-eutrophic condition with high chemical oxygen demand (COD), chlorophyll-a (Chl-a), total nitrogen (TN) and total phosphorus (TP), as estimated by stable isotope analysis. Total of 679 individuals were collected from the reservoir, and 9 species were identified. Interestingly, Lepomis macrochirus and Hemiculter eigenmanni known as less sensitive to pollution and water quality deterioration, dominated the reservoir, and their relative abundances were 38% and 27%, respectively. Further, the analysis of the stomach contents revealed that main food source of dominant L. macrochirus was high amount of zooplankton, which includes copepoda and cladocera, while Cyprinidae species mainly consumed organic particles with zooplankton preys. Stable isotope analysis also suggested that L. macrochirus, Carassiusauratus, Pseudorasboraparva, and H. eigenmanni are major zooplantivorous group in the Jeondae Reservoir.

• Korean Journal of Food Science and Technology
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• v.21 no.4
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• pp.583-589
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• 1989

In order to improve the quality and yields of barley tea(water extracts), enzymatic hydrolysis was carried out with using three kinds of mired enzymes of ${\alpha}-amylase,\;{\beta}-amylase$ and protease. The barley treated with enzymes were the crushed , soaked and slightly roasted(light brown) Youngsanbori(hulless) and the physical, chemical and sensory characteristics were investigated. The results showed that enzymatic hydrolysis caused a signigicant increase in solid yields (80%) of barley tea, particularly with the mixed enzyme 5,000 which has higher activity of ${\alpha}-amylase$ than the other enzymes. The intrinsic viscosity of barley tea was reduced by enzymatic hydrolysis as the value of dextrose equivalent increased The Hunter L, a, b values was lower for the enzyme treated barley tea but showed not significant difference with reaction time. The organoleptic evaluation clearly showed that both intensity and acceptability of odor and taste was markedly Increased. The roasted nutty, and sweety odor and taste were particular in increase by mixed enzyme 5,000.

• Journal of Animal Science and Technology
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• v.50 no.2
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• pp.247-254
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• 2008

A total of 40 pigs were used to investigate the feeding effects of supplementary wild grape wine by-product on pork quality of American Berkshire breed in the swine farm of Hamyang area. Treatments were C that was basal diet, and T that was treated by dietary wild grape wine by-product(5%) were added in feed. About 70 kg pigs were bred a period of 88 days, and slaughtered. The pork quality characteristic were measured in pork loin. In chemical composition, moisture and crude fat were not significantly different between C and T, but T were lower(p<0.05) than C. There were no difference in crude protein and crude ash(p<0.05). pH and water holding capacity(WHC) were not significantly different between C and T, whereas the cholesterol and fat shear force of T were lower(p<0.05) than C. There were no different in the meat color, but the Hunter’s L* and W value of T were higher(p<0.05) than C. Oleic acid(C18:1), linoleic acid(C18:2, n-6), arachidonic acid(C20:4, n-6), Essential fatty acid(EFA), and EFA/unsaturated fatty acid were significantly(p<0.05) different between C and T, in the fatty acid compositions of loins. Also, the total amino acid composition of pork were not significantly different between C and T, but essential fatty acid of T was significantly higher(p<0.05) than that of C. This observation suggests that wild grape wine by-product supplements may have some beneficial effects on improving backfat color, shear force, cholesterol and essential fatty acid content of pork loin.