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Effects of Capillary Rise Interruption Layer on Salt Accumulation and Kentucky Bluegrass (Poapratensis L.) Growth in Sand Growing Media Established Over the Reclaimed Saline Soil (임해 간척지에서 모래상토 층에 모세관수 차단 층의 도입이 염류 집적과 켄터키블루그래스 생육에 미치는 영향)

  • Rahayu, Rahayu;Yang, Geun-Mo;Choi, Joon-Soo
    • Proceedings of the Turfgrass Society of Korea Conference
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    • 2011.02a
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    • pp.5-8
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    • 2011
  • This research was conducted to determine the effect of capillary rise interruption layer on the sand based growing media when growing Kentucky bluegrass under soil reclamation and saline water irrigation. Rootzone profile consists of three layers as top soil of 30 cm, 20 cm of capillary interruption layer and 10 cm of reclaimed paddy soil. Rootzone profile was packed in column pots. The top soil was a mixture of sand dredged up from Lake Bhunam Tae Ahn, Korea and peat at the ratio of 95:5 by volume. Bottom part of column was covered with plastic net and the pots were soaked into 5 cm depth saline water reservoir with salinity $3-5dsm^{-1}$. Kentucky bluegrass was installed by sod and irrigated using $2dSm^{-1}$ saline water(5.7mm $day^{-1}$)in 3days interval. The results showed that the largest accumulation of salt in the spring with ECe of $5.4dSm^{-1}$ and SAR34.0 in rootzone with out capillary rise interruption layer and ECe of $4.6dSm^{-1}$ and SAR8.24 at rootzone using gravel as capillary rise interruption layer material. Kentucky bluegrass grown in growing media with gravel as capillary rise interruption layer resulted in the average visual quality rate of 8.1and clipping dry weight of $24.8gm^{-2}$, while Kentucky bluegrass grown in the growing media with out capillary rise interruption layer showed the visual quality rate of 7.9 and clipping dry weight of $34g.m^{-2}$. Capillary rise interruption layer of gravel and coarses and enhanced the visual quality by 4.1and 4.0%, root length by 50 and 38%, and root dryweight by 35and 17% of Kentucky bluegrass, and reduced the accumulation of Na by 16% and 25%, ECe by 7% and 13% in the rootzone.

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Changes in microbial and chemical properties of rough rice treated with cold plasma by storage temperatures and periods (저온 플라즈마 처리한 벼의 저장온도 및 기간에 따른 미생물학적 및 이화학적 특성 변화)

  • Woo, Koan Sik;Yong, Hae In;Jo, Cheorun;Lee, Seuk Ki;Lee, Byong Won;Lee, Byoungkyu;Lee, Yu-Young;Oh, Sea-Kwan;Kim, Hyun-Joo
    • Food Science and Preservation
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    • v.24 no.7
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    • pp.908-914
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    • 2017
  • Cold plasma (CP) was applied to examine microbial safety and physicochemical properties of rough rice. CP was generated in a square-shaped plastic container (250 W, 15 kHz, ambient air) and dielectric barrier discharge plasma treatment was applied for periods of 0, 10, and 20 min during 2 weeks at 4 and $25^{\circ}C$. As a result of observing changes in growth of microorganisms, 3.46-3.86 log CFU/g of total aerobic bacteria and 2.27-2.86 log CFU/g of mold were detected in the early stage of storage. The growth of total aerobic bacteria and mold was increased depending on the storage temperature and period, but there was no big difference between cultivars. Microbial analysis after storage showed that microorganisms of plasma-treated group were less grown approximately 1.50 log CFU/g. Moisture content of rough rice was decreased by storage temperature and periods. As for the amylose content, changes in the content by plasma were not observed in Samkwang, Cheongpum and Misomi, whereas Palbangmi showed a tendency to increase. The results of this study indicated that CP treatment improved the microbial quality of rough rice, but further studies should be conducted to reduce the deterioration of sensory quality induced by CP.

Actual State of Structures and Environmental Control Facilities for Tomato Greenhouses in Chungnam Region (충남지역 토마토 재배온실의 구조와 환경조절설비 실태분석)

  • Nam, Sang-Woon;Kim, Young-Shik
    • Korean Journal of Agricultural Science
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    • v.36 no.1
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    • pp.73-85
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    • 2009
  • An investigation was conducted to get the basic data for establishing structural safety and environmental management of tomato greenhouses in Chungnam region. The contents of the investigation consisted of actual state of greenhouse structures and environmental control facilities. Most of greenhouses were arch type single-span plastic houses and they had too low height for growing tomatoes. Frameworks of multi-span greenhouses were suitable, but those of single-span were mostly insufficient. Every greenhouse had thermal curtain movable or covering fixed inside the greenhouse for energy saving, and heating facilities were mostly warm air heater. Irrigation facilities were mostly drip tube and controlled by manual operation or timer. Almost all of the greenhouses didn't install high level of environmental control facilities such as ventilator, air circulation fan, $CO_2$ fertilizer, insect screen, supplemental light, and cooling device.

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Effects of Kinds of Cryoprotectants on the Characteristics of Frozen Fowl Semen (닭 정액 동결 시 동결 보호제가 정액 성상에 미치는 영향)

  • Choi, Jin Seok;Shin, Dan-Bi;Ko, Yeoung-Gyu;Do, Yoon-Jung;Byun, Mijeong;Park, Soo-Bong;Seong, Hwan-Hoo;Kim, Hyun;Kong, Il-Keun;Kim, Sung Woo
    • Korean Journal of Poultry Science
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    • v.40 no.3
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    • pp.171-178
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    • 2013
  • The purpose of this study was to evaluate the sperm viability, normal acrosome and mitochondrial activity in the frozen-thawed fowl semen by different cryoprotectants. The experiment was carried out on 10 sexually adult roosters of Ogye. The semen was collected twice a week and pooled semen was diluted 1:1 EK extender containing no cryoprotectant at $5^{\circ}C$. After equilibration for 30 minutes, diluted chicken semen was diluted 1:1 extender containing either 7% dimethylacetamide (DMA), 7% dimethylformamide (DMF) or 7.5% methylacetamide (MA) at final concentration and was put in 0.5 mL plastic straws and frozen for 30 minutes by exposure to liquid nitrogen vapor 4 cm above the surface of liquid nitrogen, followed by plunging into liquid nitrogen. Frozen semen was thawed in water bath at $5^{\circ}C$ for 2 minutes. For cytometric analysis, the frozen-thawed semen was diluted with EK extender to a final concentration of 90 million spermatozoa per mL. Sperm membrane integrity was evaluated as SYBR-14 and propidium iodide (PI). Acrosome integrity was assessed with fluorescein isothiocyanate-labeled PSA and PI. The percentage of mitochondrial function was estimated by using Rhodamine123 (R123) and PI. In conclusion, freezing rooster semen by using 7% DMF as cryoprotectant was significantly highest in rates of survival and mitochondrial function while its rate of damage of acrosome was significantly lowest. As a result, DMF is the cryoprotectant that has the lowest influences on sperm membranes and acrosome integrity. Therefore it could be used for freezing method of animal genetic conservation method for poultry diversity.

Effect of Various Forms of Floor System on Performance of Meat-type Duck and Environments of Duck House (오리사 바닥 형태가 육용오리의 생산성 및 사육환경에 미치는 영향)

  • Bang, Han-Tae;Kim, Dong-Woon;Hwangbo, Jong;Na, Jae-Cheon;Kang, Hwan-Ku;Kim, Min-Ji;Mushtaq, M.M.H.;Parvin, R.;Choi, Hee-Chul;Lee, Sang-Bae;Kang, Min;Kim, Ji-Hyuk
    • Korean Journal of Poultry Science
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    • v.40 no.3
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    • pp.253-262
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    • 2013
  • This experiment was conducted to investigate the effects of floor type and heating system on performance, housing environment and health status of ducks reared in three types of duck house (OD : Open floor house-Direct heating system, OF : Open floor house-Floor heating system and LD : Loft type house-Direct heating system). In OF treatment, PVC pipes were installed for heating under concrete floor and covered with litter. In LD treatment, plastic mesh was installed 50 cm above the floor so that duck's droppings can pass through it. Each treatment had four replicates of 25 birds (Cherry Valley duck breed) per pen. There were no significant differences in weight gain and feed intake of ducks for 6 weeks among all treatments. However, feed conversion ratio in LD was significantly higher (p<0.05) than that in OF. No differences were found in carcass charac- teristics, with the exception of abdominal fat weight where OF were higher than the others. Concentrations of $CO_2$ and $NH_3$ gas in OD were higher than those of OF and LD at 3, 4 and 5 weeks. Moisture content in litter of OF was lower than that of OD. In contrast, the amount of dust in the air was higher in OF than in OD. The amount of fuel used for 6 weeks in LD was lower about 21% than that in OD. Some of unusual symptoms were observed in open floor house and loft type house, such as lying, spraddle legged, twisted ankle and legs, wounded sole, or etc. No components of leukocyte and erythrocyte of blood were significantly different among all treatments. The results of this experiment showed that OF and LD systems had no positive effects on performance of meat type commercial duck. However, there were some positive effects of certain house type for the improvement of environmental condition in duck house for hygienic production. In the future, more research on the effect of various facilities and systems for duck house is needed.

Effect of Package Size and Pasteurization Temperature on the Quality of Sous Vide Processed Spinach (Sous Vide 가공 시금치의 품질에 미치는 포장단위 및 살균온도의 영향)

  • 장재덕;김기태;이동선
    • Food Science and Preservation
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    • v.11 no.2
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    • pp.195-200
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    • 2004
  • Microbial lethal value and nutrient retention of sous vide processed spinach were evaluated with mathematical model prediction and experimental trial for different package sizes and pasteurization temperatures. The package size covers 500 g, 1 kg and 2 kg, while the pasteurization temperature includes 80, 90 and 97$^{\circ}C$. The basic process scheme consists of filling blanched spinach into barrier plastic film pouch, sealing under vacuum, pasteurization in hot water with over pressure and final cooling to 3$^{\circ}C$. Pasteurization condition was designed based on attainment of 6 decimal inactivation of Listeria monocytogenes at geometric center of the pouch package by heating cycle, which was determined by general method. Heat penetration property of the package and thermal destruction kinetics were combined to estimate the retention of ascorbic acid and chlorophyll. Smaller packages with shorter pasteurization time gave better nutrient retention, physical and chemical qualities. Larger package size was estimated and confirmed experimentally to give higher pasteurization value at center, lower ascorbic acid and chlorophyll contents caused by longer heat process time. Lower pasteurization temperature with longer process time was predicted to give lower pasteurization value at center and lower ascorbic acid, while chlorophyll content was affected little by the temperature. Experimental trial showed better retention of ascorbic acid and chlorophyll for smaller package and higher pasteurization temperature with shorter heating time. The beneficial effect of smaller package and higher pasteurization temperature was also observed in texture, color retention and drip production.

The Influence of Admixture of Lignosulfonic Acid Type on the Strength of Mortar (Lignosulfonic Acid계(系) 감수제(減水劑)가 모르터의 강도(强度)에 미치는 영향(影響))

  • Kim, Han Young;Kim, Seong Wan
    • Korean Journal of Agricultural Science
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    • v.12 no.1
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    • pp.75-85
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    • 1985
  • This study is intended to find out the influence of Lignosulfonic Acid Type Admixture on compressive, tensile, flexural strength and dispersing action of mortar, and fixation of by-product of pulp industry. 1. The more Pozzolith-84 is added, the larger flow value is. The admixture of lignosulfonic acid type adhere to cement particles and the surface potential of particles is generated. On account of the repulsion among the cement particles, they are dispersed and the mortar get workable, so the production cost of precast product is curtailed and the amount of cement is reduced in a certain workability of mortar. 2. The strength of mortar is greater than plain mortar when P/C added is 0.2 and 0.4%. As time passed the potential energy is reduced and the distance of particles which lignosulfonic acid adhered to get near according as the amount of adhesion is increased. The setting and hardening reaction of morter is occurred in close state, so the strength of mortar is increased a little. The strength of mortar is less than plain mortar when amount P/C added is 0.8%. Pozzolith-84 is mainly composed of lignosulfonic acid and lignin does not influence the hardening of mortar, therefore the remained $SO_3$, $SO_3H$ are the reason of decrease of strength. 3. There is high significance between specific gravity and compressive strength. The larger specific gravity is, the more compressive strength is increased. There is high significance between 7 day's strength and 28 day's strength. The larger compressive strength is, the more tensile and flexural strength are increased. 4. Since Pozzolith-84 is a by-product of pulp industry, by using the Pozzolith-84 admixture the concreate quality is improved. The water pollusion is reduced according to fix by-products in concrete structure.

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Present status and prospect for development of mushrooms in Korea

  • Jang, Kab-Yeul;Oh, Youn-Lee;Oh, Minji;Im, Ji-Hoon;Lee, Seul-Ki;Kong, Won-Sik
    • 한국균학회소식:학술대회논문집
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    • 2018.05a
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    • pp.27-27
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    • 2018
  • The production scale of mushroom cultivation in Korea is approximately 600 billion won, which is 1.6% of the Korean gross agricultural output. Annually, ca. 190,000 tons of mushrooms are harvested in Korea. Although the numbers of mushroom farms and cultivators are constantly decreasing, the total mushroom yields are increasing due to the large-scale cultivation facilities and automation. The recent expansion of the well-being trend causes increase in mushroom consumption in Korea: annual per capita consumption of mushroom was 3.9kg ('13) that is a little higher than European's average. Thus the exports of mushrooms, mainly Flammulina velutipes and Pleurotus ostreatus, have been increased since the middle of 2000s. Recently, however, it is slightly reduced. However, Vietnam, Hong Kong, the United States, the Netherlands and continued to export, and the country has increased recently been exported to Australia, Canada, Southeast Asia and so on. Canned foods of Agaricus bisporus was the first exports of the Korean mushroom industry. This business has reached the peak of the sale in 1977-1978. As Korea initiated trade with China in 1980, the international prices of mushrooms were sharply fall that led to shrink the domestic markets. According to the high demand to develop new items to substitute for A. bisporus, oyster mushroom (Pleurotus ostreatus) was received the attention since it seems to suit the taste of Korean consumers. Although log cultivation technique was developed in the early 1970s for oyster mushroom, this method requires a great deal of labor. Thus we developed shelf cultivation technique which is easier to manage and allows the mass production. In this technique, the growing shelf is manly made from fermented rice straw, that is the unique P. ostreatus medium in the world, was used only in South Korea. After then, the use of cotton wastes as an additional material of medium, the productivity. Currently it is developing a standard cultivation techniques and environmental control system that can stably produce mushrooms throughout the year. The increase of oyster mushroom production may activate the domestic market and contribute to the industrial development. In addition, oyster mushroom production technology has a role in forming the basis of the development of bottle cultivation. Developed mushroom cultivation technology using bottles made possible the mass production. In particular, bottle cultivation method using a liquid spawn can be an opportunity to export the F.velutipes and P.eryngii. In addition, the white varieties of F.velutipes were second developed in the world after Japan. We also developed the new A.bisporus cultivar "Sae-ah" that is easy to grown in Korea. To lead the mushroom industry, we will continue to develop the cultivars with an international competitive power and to improve the cultivation techniques. Mushroom research in Korea nowadays focuses on analysis of mushroom genetics in combination with development of new mushroom varieties, mushroom physiology and cultivation. Further studied are environmental factors for cultivation, disease control, development and utilization of mushroom substrate resources, post-harvest management and improvement of marketable traits. Finally, the RDA manages the collection, classification, identification and preservation of mushroom resources. To keep up with the increasing application of biotechnology in agricultural research the genome project of various mushrooms and the draft of the genetic map has just been completed. A broad range of future studies based on this project is anticipated. The mushroom industry in Korea continually grows and its productivity rapidly increases through the development of new mushrooms cultivars and automated plastic bottle cultivation. Consumption of medicinal mushrooms like Ganoderma lucidum and Phellinus linteus is also increasing strongly. Recently, business of edible and medicinal mushrooms was suffering under over-production and problems in distribution. Fortunately, expansion of the mushroom export helped ease the negative effects for the mushroom industry.

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Study on the Manufacturing techniques & Conservation of Iron Pot from Cheonmachong Ancient Tomb (천마총 출토 철부(鐵釜)의 제작기법 및 보존처리)

  • Lee, Seung Ryul;Shin, Yong Bi;Jung, Won Seob
    • Journal of Conservation Science
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    • v.30 no.3
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    • pp.263-275
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    • 2014
  • It's shown how to proceed the study on Manufacturing techniques & Conservation to the Iron Pot from Cheonmachong Ancient Tomb(the 155th Tomb in Hwangnam-dong). In order to investigate manufacturing techniques of the Iron Pot, some parts of the relic were gathered. After mounting, polishing and etching on the relic, analyzing the metal microstructure was conducted. Also it's conducted a SEM-EDS analysis on the nonmetallic inclusion. White iron structure was observed in the metallurgical structure inspection, SEM-EDS analysis. It seems to be dried slowly at room temperature after casting, doesn't look as particular heat treatment to improve brittleness. It is estimated that it's as the handle seam side were verified about 3cm inch wide, 1.5 thick in center of body, so 2 separate half-completed products was cast with width-type mould. The manufacturing techniques Using white cast iron structure, width-type mould are observable to the Iron Pot excavated from Sikrichong Ancient Tomb & Hwangnamdaechong grand Ancient Tomb around those were constructed the same time. It's able to recognize that it's almost identical manufacturing techniques at that time. Conservation is generically following those are survey of pretreatment, foreign material removal, stabilization, restoration and color matching in the order. cleaning & drying were added to the process as occasion demands. The strengthening treatment were difficult with artifact's volume, low concentration Paraloid NAD-10 solution was spread two or three times with a brush, surface hardening also came up with 15wt% Paraloid NAD-10 solution after the conservation was complete. There were connection & restoration for the restoration to the damage after modeling forms that it's similar to damaged parts by using the Fiber Reinforced Plastic resins(POLYCOAT FH-245, mold laminated type). Throughout this research, capitalizing on accumulations of measurements about the production technique of Iron Pot in the time of the fifth and 6th centuries is no less important than the Iron artifact's conservation for a better study in the future.

The Photocatalytic Degradation of Humic Acid by TiO2 Sol-Gel Coating -Characterization of Humic Acid in the Chemical Oxidation Treatment (II)- (TiO2 졸-겔 코팅 막에 의한 Humic Acid의 광분해 -화학적 산화법에 의한 부식산의 분해처리 기술에 관한 연구 (II)-)

  • Seok, Sang Il;Ahn, Bok Yeop;Suh, Tae Soo;Rhee, Dong Seok
    • Journal of Korean Society of Environmental Engineers
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    • v.22 no.4
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    • pp.765-773
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    • 2000
  • The degradation of humic acid using $TiO_2$ coatings was studied, $TiO_2$ coatings were prepared by dip-coating method. Sol solutions for coating were prepared by mixing the gel, which can be produced by the reaction of $TiOCl_2$ and $NH_4OH$ solution, and hydrogen peroxide solution, and hydrolysis of titanium tetraisopropoxide (TTIP). It was shown from XRD that coatings from sol aged at $100^{\circ}C$ for 18h with titanium peroxo solution were crystallized to anatase in the range of temperatures of $25^{\circ}C$ to $500^{\circ}C$. In contrast, those coated from TTIP were crystallized to anatase at temperature above $400^{\circ}C$. So the sols originated from $TiCl_4$ can be applied for not only on the heat-resistance substrates but on the plastic substrates. Thickness and the quality of the films were dependent on the withdrawing speed, the concentration of sol, and the number of coating. The films showed various interference colors depending on the thickness of them. In the case that the films coated 2 times at withdrawing speed of 2.5cm per minute by 0.2M sol, the films had a transparent light blue color with thickness of around 50nm. It was known from the result of photo-degradation by $TiO_2$ coatings using humic acid that the removal efficiency of $COD_{cr}$ was over 85% after illumination of $UV/H_2O_2$ for 40min. and that of UV/VIS absorbable materials was over 95%.

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