• Proceedings of the Korea Society of Poultry Science Conference
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• 2003.07b
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• pp.67-88
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• 2003

The consumption of poultry meat (chicken and turkey) grew the most during the past few decades due to several contributing factors such as low price. product research and development. favorable meat characteristics, responsive to consumer needs, vertical integration and industry consolidation, new processing equipments and technology, and aggressive marketing. The major processing technologies developed and used in chicken processing include forming/restructuring, tumbling, curing, smoking, massaging, injection, marination, emulsifying, breading, battering, shredding, dicing, and individual quick freezing. These processing technologies were applied to various parts of chicken including whole carcass. Product developments using breast, thigh, and mechanically separated chicken meat greatly increased the utilization of poultry meat. Chicken breast became the symbol of healthy food, which made chicken meat as the most frequent menu items in restaurants. However, the use of and product development for dark meat, which includes thigh, drum, and chicken wings were rather limited due to comparatively high fat content in dark meat. Majority of chicken are currently sold as further processed ready-to-cook or ready-to-eat forms. Major quality issues in chicken meat include pink color problems in uncured cooked breast, lipid oxidation and off-flavor, tenderness PSE breast, and food safety. Research and development to ensure the safety and quality of raw and cooked chicken meat using new processing technologies will be the major issues in the future as they are now. Especially, the application of irradiation in raw and cooked chicken meat products will be increased dramatically within next 5 years. The market share of ready-to-eat cooked meat products will be increased. More portion controlled finished products, dark meat products, and organic and ethnic products with various packaging approaches will also be introduced.

• Korean Journal of Organic Agriculture
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• v.9 no.2
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• pp.101-115
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• 2001

Nitrogen applied as fertilizer for crop production is partly absorbed by plant , and the remaining nitrogen in soil might be leached out through complicated processes to the subsoil layer Especially, NO$_3$-N in leachate causes environmental pollution. The purpose of this study was focused on understanding of uptake of nutrients by plants, the behaviors of nutrients in soil and the possibility of leaching loss when nitrogen fertilizer and completely decomposed compost were applied. Lysimeters(Volume 0.15㎥, Diameter 62cm, Height 62.8cm) were installed for collecting leachate in the Jeju volcanic ash soils. Lysimeter study consisted of thirteen treatments : fallow, fallow with weeding, cropping without fertilizer and compost, three N fertilizer soil surface applications(16, 32, 64kg/10a), three N fertilizer and compost soil surface applications(16+800, 32+1600, 64+32kg/10a), two water dissolved N fertilizer applications(16, 32kg/10a), and low and high plant densities. N fertilizer was applied as urea. The growth of com(preceding crop) and potatoes(succeeding crop) and leaching loss were determined during the experimental period. The results obtained were summarized as follows ; With Increased N, pH of leachate tended to decrease and NO$_3$-N concentration of leachate increased. NO$_3$-N leaching loss was remarkably greater in soil from the bare plot without fertilization and the weed control than from plots with medium N rate and was least in the cropping plot without fertilization. NO$_3$-N concentration in leachates from the water dissolved N fertilizer application plots was 64% of that from the soil surface application plots. The concentration of Ca and K ions and the leaching loss of these ions were least from the cropping plot without fertilization and were greatest from bare plots(T1 and T2) without fertilization. The proportion of leaching and residual N in soil increased as N rate increased indicting that higher N rates increase the possibility of N leaching to subsoil layer The proportion of N leaching losses was lower at the low N rate and the high plant density. In future, fertilization prescription which can maximize fertilizer use efficiency and minimize the pollution of ground water will be needed for conserving the environments.

• Korean Journal of Organic Agriculture
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• v.25 no.2
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• pp.345-355
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• 2017

This study was conducted to evaluate rice seed disinfection efficacy of loess-sulfur for the suppression of Bakanae disease caused by Fusarium fujikuroi. Rice seeds were treated at different concentrations of loess-sulfur, soaking time and temperature, and combination of hot-water treatment. Rice cultivar, Shindongjin harvested from Bakanae disease-infested area in 2015, was used. Loess-sulfur was treated as follows; concentration of undiluted solution, 2%, 1% and 0.5%; soaking time of 24 and 48 hours; treatment temperature of $20^{\circ}C$ and $30^{\circ}C$; hot water treatment or not. Optimal conditions of rice seed disinfection were selected soaking time of 48 hours and the suspension of 0.5% and 1% loess-sulfur by investigating seed germination and isolation frequency of Fusarium spp. on Komada agar medium in vitro, and were established 3 disinfection conditions as hot water ($60^{\circ}C$, 10 min.) + 1% loess-sulfur ($20^{\circ}C$, 48 hours), 1% loess-sulfur only ($30^{\circ}C$, 48 hours) and 1% loess-sulfur only ($20^{\circ}C$, 48 hours) through additional test in greenhouse. Above 3 conditions were verified by rice seedling box and paddy field test in the way of investigating Bakanae diseased plants (%) and healthy plants (%). Consequently, most effective rice seed disinfection conditions on Bakanae disease were combination of hot water and 1% loess-sulfur and loess-sulfur only at $30^{\circ}C$. Furthermore, treatments with these conditions showed control value of 100% were maintained from seedling to the heading stage in the field. However, treatment of 1% loess-sulfur only at $20^{\circ}C$ showed low control value of 78.2% in paddy field. Hot water only treatment turned out to be an effective disinfection method when conducted thoroughly with $60^{\circ}C$, 10 min. However, it was thought additional soaking process with loess-sulfur after hot water treatment served more high control effect against Bakanae disease when rice seeds were disinfected on a large scale. This results expected rice seed disinfection with loess-sulfur were effectively and easily usable method if farmers had only one of either hot water-disinfector or seed-disinfector. In addition, loess-sulfur is well-known to farmers, simple to manufacture method and cheap.

• Korean Journal of Environmental Agriculture
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• v.17 no.2
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• pp.107-116
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• 1998

In an effort to reduce artifically the residual pesticides on crop and soil by accelerated photolysis,some 40 among the naturally occurring and synthetic coumpound were screened for photosensitization and/or photocatalysis and six promising chemicals were selected.The fungicides and the four selected photosensitizers and/or photocatalyst (PS) were applied to each crop.The results obtained are summarized as follows. 1. The wavelengths of maximum absortion (${\lambda}$max) and the molar absorptivites (${\varepsilon}$max) of procymidone,vinclozolin,and carbendazim in acentone were all 209 nm and 853,854,and 8740 respectively. 2. Of the 40 naturally-occuring and synthetic compounds screened,six promising ones were selected and designated as PS-1 (aromatic ketone),PS-2(aromatic amine)PS-3(quinone) ,PS-4 (inorganic compound),PS-5(organic acid salt) and PS-6(semiconductor photocatalyst). 3. In the accelerated photolysis of pesticide in soil by applying PS ,procymidone was decoposed rapidly by virtue of PS-2,being 59% of the control 3 days after application. 4. The vinclozolin residue in soil was reduced to 71% and 21% of the control 1 and 15 days,respectively,after PS-2 application. 5. The photolysis of carbendazim in soil was not accelerated by any of the PS tested. 6. The pesticide residues on the crop were prominently reduced by PS application.The procymidone residue on tomato was reduced to 47% of the control 15 days after PS-1 application and that on red pepper reduced to 57% 15 days after PS-2 application. 7. Vincrozolin residus remaining on tomato 1 and 15 days after PS-2 application were 38% and 56% of the control whereas those on the red pepper were 82% and 64%,respectively. 8. PS-2 was the most effective for the accelerated photolysis of carbendazim residues remaining on tomato, whereas on red pepper, the four of PS tested were all effective, but did not make much difference between them. This might be due to the shielding of sunlight by the leaves of red pepper not to exert the photosensitizing effect of PS-2 to the full.

• Korean Journal of Environmental Agriculture
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• v.33 no.1
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• pp.44-51
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• 2014

BACKGROUND: Water quality of rural areas are susceptible to agricultural nutrient input and supply such as chemical fertilizer and livestock manure. This study was conducted to evaluate the usefulness of nutrient (N and P) indices in understanding spatial variations of water quality across Chonnam province which is a typical agricultural region in Korea. METHODS AND RESULTS: The nutrient indices including chemical fertilizer supply, livestock manure production, and nutrient balance were correlated with water quality data (T-N, T-P, BOD, and COD) for the twenty-two districts of the province. Concentration of T-N were positively correlated with chemical fertilizer supply, livestock manure N production, and nutrient balance (P<0.05 or P<0.01). Meanwhile, T-P concentration was not correlated with these nutrient indices; however, there was a tendency that T-P concentration increases with livestock manure P production (P=0.06) and with nutrient balance (P=0.09). These results suggest that T-N concentration is susceptible to both chemical fertilizer and livestock manure; whereas T-P is likely to be affected by livestock manure rather than chemical fertilizer. The concentrations of BOD and COD were also positively (P<0.05 or P<0.01) correlated with livestock manure production. CONCLUSION: This study shows the usefulness of nutrient indices in understanding spatial variations of water quality and suggests that livestock manure rather than chemical fertilizer can be a more critical water pollution source and thus highlights the need for more attention to livestock manure treatments for rural water quality management.

• Korean Journal of Environmental Agriculture
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• v.26 no.3
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• pp.246-253
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• 2007

This study was performed to enhance the cleanup efficiency of methoxyfenozide and bentazone by pH adjustment in the course of liquid-liquid partition and to develop an optimum analytical conditions using HPLC coupled with DAD for two matrices, brown rice and rice straw. Preparation procedure of brown rice sample was "extraction${\rightarrow}$coagulation${\rightarrow}$liquid-liquid partition$\rightarrow$-florisil C.C", and this procedure was samely applied to two compounds. In rice straw, preparation procedure of methoxyfenozide sample was "extraction$\rightarrow$-alkalization$\rightarrow$liquid-liquid extraction$\rightarrow$coagulation$\rightarrow$florisil C.C", and in the case of bentazone, "extraction$\rightarrow$alkalization$\rightarrow$liquid-liquid partition$\rightarrow$acidification$\rightarrow$liquid-liquid extraction$\rightarrow$florisil C.C". All these purified samples were redissolved in the mobile phases, acetonitile : 20 mM sodium acetate (75:25, v/v) for methoxyfenozide and acetonitrile : 75 mM sodium acetate, pH 6.0 (40:60, v/v) for bentazone. Recoveries of methoxyfenozide analysis in brown rice and rice straw were 83.5-97.4 and 86.4-97.3%, and detection limits were 0.02 and 0.04 mg/kg, respectively. Recoveries of bentazone in brown rice and rice straw were 86.8-101.9 and 88.3-94.5% and detection limits were 0.005 and 0.01 mg/kg, respectively. This methods seem to be usefully applied to the residue analysis of two compounds in the view of producing stable analytical condition and fair reproducibility.

• Journal of Korean Society of Forest Science
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• v.85 no.2
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• pp.329-339
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• 1996

This study is to investigate the effect of mycorrhizal development, growth, nutrient absorption of P. thunbergii seedlings inoculated with Pisolithus tinctorius(Pt. KJ-1) in relation to toxic materials in soil. The concentrations on copper solution applied to the soils were 0, 40, 120, 260, 430ppm. The results are summarized as follows : 1. The germination of P. thunbergii with Pt. increased greater than without ectomycorrhizal fungi. Mycorrhizal development showed a significant decreasing trend at high concentration, and tolerant Cu test with Pt. in agar plate media showed a decreasing trend at a high level. 2. P. thunbergii seedlings inoculated with Pt. showed that the shoot length was significantly promoted at 40, 120ppm copper levels, and that of noninoculated seedlings had the lowest effect in 430ppm copper level. 3. The outer shape of ectomycorrhizal root tips after inoculating Pt. on P. thunbergii seedlings appeared as a monopodial type, a fern-like type, and a cluster-like type at 0ppm, 40ppm levels, but only monopodial type came out at 260ppm, 430ppm copper levels. 4. Root length, no. of juvenile leaves, total length of juvenile leaves, total dry weight, no. of needles and total length of needles of P. thunbergii with Pt. increased greater than those of noninoculated seedling. Growth response of P. thunbergii seedling inoculated with Pt. increased significantly at 40ppm, 120ppm Cu levels. 5. As a result of analysis of growth medium, pH, Na, CEC increased at higher Cu level, and total nitrogen, organic matters, available phosphorous, K, Ca and Mg decreased at 40ppm, 120ppm Cu levels. As a result of an analysis about a copper within soils, it appeared having high Cu-concentration at 0ppm level of an inoculated Pt. and high Cu-concentration in noninoculated Pt. than in inoculated Pt. at higher level. 6. As a result of an analysis of shoot, N, P, and K-concentration were higher in noninoculated seedlings than in inoculated seedlings, and Cu-concentration was higher in inoculated seedlings than in noninoculated seedlings. The analysis of root resulted in a high N-concentration at 40ppm, 120ppm levels, in a high P-concentration in inoculated seedlings and in a high Cu-concentration in noninoculated seedlings. Cu-concentration was significantly higher at root than at shoot.

• Journal of Aquaculture
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• v.12 no.1
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• pp.47-56
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• 1999

Denitrification by anaerobic bacteria is one of the most common processes of removing nitrate from recirculating aquaculture systems. This process is affected by many factors such as external carbon sources, hydraulic retention time (HRT), and $COD/NO_3-N$ ratio. Although external organic carbon sources are essential for the denitrification process, these also contribute to increase dissolved organic carbon concentration in recirculating aquaculture systems. So these external organic carbons must be removed from the systems. This study was conducted to find out the optimum operating conditions for the removal of external organic carbons in a submerged denitrification biofilter. Combinations of two external carbon sources (glucose and methanol), two HRT (4- and 8-hour), and four different C:N ratios (3, 4, 5, and 6) were used in this experiment. The removal efficiencies of organic carbon sources at 8-hour HRT were always better than those at 4-hour's (P<0.05). Maximum removal efficiencies were achieved when C:N ratio was 5 in both glucose and methanol. The removal efficiencies of methanol were always better than those of glucose. The maximum removal efficiencies of glucose and methanol were 76.5% and 84.0%, respectively and the removal rates were 223.5 $g/m^2/day$ and 247.1$g/m^2/day$. The maximum removal rates of glucose (290.9 $g/m^2/day$) and methanol (355.6 $g/m^2/day$) were achieved at 4-hour HRT and 5 C:N ratio. But the concentrations of SCOD in the effluent of both glucose ($52.5 mg/\ell$) and methanol ($40.9 mg/\ell$) were too high for rearing fish. Therefore, the optimum operating conditions for the removal of external carbon in a submerged denitrification biofilter were 8-hour HRT and 5 C:N ratio. And methanol showed better efficiency as an external carbon sources.

• Journal of Korean Society of Forest Science
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• v.103 no.1
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• pp.65-71
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• 2014

Cacalia firma is a perennial plant in Asteraceae, Parasenecio that distributed in Korea, China, and Japan. As dietary style changes for well-being life, consumer's demand of functional food and organic vegetables is getting increased. This study was conducted to investigate the optimum light conditions of P. firmus in forest farming. One year old seedlings were grown under four different light conditions 10%, 20%, 30%, and 50% of sunlight by shading (equals 50%, 30%, 20%, and 10% relative brightness respectively) and non-treated control under full sunlight. They were analyzed for early growth and physiological response. Seedlings grown under 75% shading showed similar height, root growth, and leaf water content to control. However, their leaf length, width, and total leaf area were increased, which caused increased leaf dry weight and total dry weight. Especially, seedlings under 95% shading showed 40% increase in height and more leaf growth and leaf water content, although they had shorter main root length and root collar diameter than control. In addition specific leaf area (SLA) and leaf area ratio (LAR) were higher than control and indicated that they were statistically significant difference from control. Higher SLA refers thinner leaf thickness, higher LAR means larger leaf area. The results indicate seedlings under 95% shading have higher water content, thinner leaf, and wider lightinterception areas. It is plausible that P. firmus is active in chlorophyll activities and carbon dioxide assimilation at even lower light conditions. These results suggest that the optimum light level of P. firmus for artificial cultivation in forest farming ranges from 75~95% shading (20%-10% of relative brightness). When salability as 'sanchae' (wild edible greens) is considered, P. firmus could be cultivated under 75% shading in forest farming and expected to have better taste and higher yield. We suggest these results as basic data of P. firmus for possible forest farming.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.1
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• pp.61-71
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• 2000

When irradiate the power ultrasound into the aqueous solutions, water vapor is decomposed by the heat of very high temperature in the cavitation bubble to produce OH (hydroxyl radical) and H (hydrogen radical), and these radicals play a role in decomposing the substances in aqueous solution by oxidation and/or reduction, and in producing the hydrogen peroxide. Accordingly it is possible to predict that the quantity of hydrogen peroxide produced may correlate with the sonolysis mechanism of the substance in aqueous solution. Thus to confirm this prediction, the quantities of hydrogen peroxide produced from each of the air saturated distilled water and three aqueous solutions of TCE, benzene, and 2,4-DCP that are prepared by dissolving them into distilled water are measured. As a result, it showed that the quantity of hydrogen peroxide produced from the distilled water and three aqueous solutions are increased in order of distilled water>TCE solution>2,4-DCP solution>benzene solution, and decrease with decrease in concentration of organic substance, which coincide with the sonolysis mechanisms reported that TCE in aqueous solution is decomposed directly by the pyrolysis in and around the cavitation bubbles when its concentration is high and by the radical reaction when low, however, benzene and 2,4-DCP are decomposed not only by the pyrolysis but also by the radical reactions. Effects of such experimental parameters as the acoustic frequency and power and as the concentration showed that the higher the acoustic frequency and the lower the acoustic power, the less the quantity of hydrogen peroxide was produced. This result coincide with the theory of ultrasound for the relation between the cavitation that is the energy source of the power ultrasound in aqueous solution and these experimental parameters.