• Journal of Dairy Science and Biotechnology
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• 제32권2호
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• pp.71-76
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• 2014

The Netherlands produce more than 11 million tonnes of milk per year, and approximately 60% of the milk is exported. Dutch milk production is five times higher than that of Korea, even though Korea comprises a land area three times greater than the Netherlands. Upscaling and intensification have characterized the Dutch way of dairy farming since 1960, and adverse effects of the intensification of dairy farming became evident from the late 1970s and early 1980s onwards. The transition toward a more sustainable farming system is a central element of the Dutch agenda for the reconstruction of the livestock production sector. The environmental problems in Dutch dairy farming in the 1980s have led to the establishment of the experimental dairy farm "De Marke" which aims at improving the utilization of fertilizers and feeds, through minimizing nutrient requirements, maximizing the use of nutrients in organic manure and homegrown feeds, and through the targeted use of fertilizers and feeds. 85 cows at "De Marke" produce 720 tonnes of milk per year, using 55 ha of pasture in a sustainable manner. That means, 150,000 ha of pasture are required to produce 2 million tonnes of milk, which the current milk production of Korea. It is urgent to provide sufficient pasture for sustainable milk production in Korea, and primarily the transition to pasture of surplus rice paddies, resulting from of a decrease in rice consumption, should be considered.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제54권9호
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• pp.421-426
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• 2005

A wire-plate discharge system with a slit barrier has been proposed and investigated experimentally by focusing on the discharges on the slit barrier and ozone generation characteristics. This wire-plate discharge system with a slit barrier can generate an intensive corona discharges, and produce corona discharge twice, once from the corona wire electrode and second time from the surface and the slits of the slit dielectric barrier. As a result this propose wire-plate discharge system with the slit barrier can produce greatly increased ozone than without the slit barrier. This type of wire-plate discharge system with the slit barrier could be used for effective ozone generation as a means with retard to the removal of pollutant gas

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 춘계학술발표대회
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• pp.351-354
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• 2000

1.3-Propanediol as a bifunctional organic compound could potentially be used for many synthesis reactions, in particular as a monomer for polycondensations to produce polyesters, polyethers and polyurethanes. Wastewater containing high concentration of glycerol was used to produce 1,3-propanediol in lower production cost which inturn the quantity of wastewater to be treated. In this study, various attempts were made to increase 1,3-propanediol production under different conditions by Klebsiella pneumoniae ATCC 15380. 1,3-Propanedio conversion yield and by-product formation were influenced significantly by pH and temperature. The Optimal glycerol and nitrogen concentration for 1,3-propanediol production were found to be 25g/L and 1%(w/v), respectively. The production formation of 1,3-propanediol was optimal at pH 6.0 and temperature $35^{\circ}C$.

• Biotechnology and Bioprocess Engineering:BBE
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• 제10권3호
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• pp.167-179
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• 2005

Chiral epoxides are highly valuable intermediates, used for the synthesis of pharmaceutical drugs and agrochemicals. They have broad scope of market demand because of their applications. A major challenge in modern organic chemistry is to generate such compounds in high yields, with high stereo- and regio-selectivities. Epoxide hydrolases (EH) are promising biocatalysts for the preparation of chiral epoxides and vicinal diols. They exhibit high enantioselectivity for their substrates, and can be effectively used in the resolution of racemic epoxides through enantioselective hydrolysis. The selective hydrolysis of a racemic epoxide can produce both the corresponding diols and the unreacted epoxides with high enantiomeric excess (ee) value. The potential of microbial EH to produce chiral epoxides and vicinal diol has prompted researchers to explore their use in the synthesis of epoxides and diols with high ee values.

• 한국분말재료학회지
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• 제10권3호
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• pp.186-189
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• 2003

A chemical vapor condensation (CVC) process using the pyrolysis of metal-organic precursors was applied to produce the nanosized $WO_3$ powders. Morphology and phase changes of the synthesized $WO_3$ powder as a function of CVC parameters were investigated by XRD, BET and TEM. The agglomerated nanosized monoclinic $WO_3$ powders with nearly spherical shape and 10-38 nm in mean diameter could be obtained. Conditions to produce the $WO_3$ nanopowders are presented in this paper.

• 한국환경과학회지
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• 제3권3호
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• pp.285-296
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• 1994

The objective of this study was to examine and compare to transient response to quantitative and hydraulic shocks which produce equal changes in mass rate of organic feed in aerobic fixed-film process. The general experimental approach was to operate the system at several growth rates under steady-state(pre-shock) conditions, then to apply step changes during day 3 in dilution rate(hydraulic shock) , or feed concentration(Quantitative shock) at the same organic mass loading rate. Performance was assessed in both the transient state and the new steady-state (post- shock). Shock load of different type did not produced equivalent disruptions of effluent quality for equal increases in mass loading rate. Based on effluent concentrations, a hydraulic and a Quantitative shock at the same mass loading caused equal increase in total effluent COD, but the increase was primarily a result of suspended solids the hydraulic shock and COD in the quantitative shock. The time which effluent COD came to peak values were about 32~48 hours at the low organic loads and 52 ~ 72 hours at the high organic loads, respectively A quantitative shock produced a much greater increase in effluent COD than did a hydraulic shock at the same mass loading. Mean and peak values of effluent concentration weve increased in 2.8~4.2 times at low organic loading rate, 5.2~6.6 times at the high organic loading rate, respectively. Key words : Aerobic fixed-film reactor, Quantitative shock, hydraulic shock, mass loading rate.

• 한국식품영양학회지
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• 제23권1호
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• pp.70-75
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• 2010

본 연구는 한국의 누룩에서 분리한 Rhizopus sp. ZB9로서 탁주 및 약주 양조에 필요한 쌀 입국을 제조할 때에 배양 온도, 배양 시간, 증미 수분 함량, 입국 두께, 교반 작업 등의 배양 조건이 입국의 유기산 생성에 미치는 영향을 알기 위한 것이다. Rhizopus sp. ZB9를 접종하여 배양 조건을 달리하여서 쌀 입국을 제조하고, 각 입국의 산도를 측정하였다. 유기산 생성에 적절한 온도범위는 $28{\sim}32^{\circ}C$이었으며, 이 온도에서 36~48시간 정도 배양하는 것이 가장 적절하였다. 증미의 수분 함량을 25%에서 60%로 높임에 따라 유기산 생산은 비례적으로 증가하였다. 입국의 두께가 두꺼워지더라도 유기산 생성에 나쁜 영향을 나타내지 않았으며, 배양 중의 교반 작업은 유기산 생성에 매우 효과적이었다.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• 제10권S_2호
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• pp.79-88
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• 2001

Humic acids react with chlorine to produce Trihalomethanes(THMs), known as carcinogens, during disinfection, the last stage in water purification. Currently, the removal of organic humic acids is considered the best approach to solve the problem of THM formation. Accordingly, the current study examined the adsorption of organic compounds of humic acids onto an inorganic carrier prepared from oyster shell waste. The adsorbent used was activated oyster shell powder(HAP) and silver ion-exchanged oyster shell powder(HAP-Ag), with CaCO$_3$ as the control. The adsorbates were phthalic acid, chelidamic acid, catechol, dodecylpyridinium chloride(DP), and 2-ethyl phenol(2-EP). The adsorption experiments were carried out in a batch shaker at $25^{\circ}C$ for 15 hours. The equilibrium concentration of the adsorbate solution was analyzed using a UV spectrophotometer and the data fitted to the Langmuir isotherm model. Since the solution pH values were found to be greater than the pKa values of the organic compounds used as adsorbates, the compounds apparently existed in ionic form. The adsorptive affinities of the organic acid and phenolic compounds varied depending on the interaction of electrostatic forces, ion exchange, and chelation. More carboxylic acids and catechol, rather than DP and 2-EP, were adsorbed onto HAP and HAP-Ag. HAP and HAP-Ag exhibited a greater adsorptive affinity for the organic compounds than CaCO$_3$, used as the control.

• 환경영향평가
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• 제22권4호
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• pp.345-359
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• 2013

The Ministry of Environment established a plan for advancement of livestock manure management in July 2011 and finalized the "Comprehensive Measures for Advancement of Livestock Manure Management" in May 2012 complementing and strengthening the plan. In this process, it was necessary to investigate the status of discharge of livestock manure and its environmental impact, for example on rivers, groundwater, arable outflow water and soil. We investigated types of livestock husbandry, discharge of livestock manure, and production and use of organic fertilizers and presented the improvement measures of livestock manure management and organic fertilizer use. First, it is necessary to come up with measures to calculate appropriate density and numbers of livestock animals and prevent overcrowded breeding. Second, as many of the private livestock manure treatment facilities are out-dated and their long-term aerated reaction tanks are not regularly managed, it is necessary to find ways to improve those facilities through inspection and diagnosis. In addition, since existing public treatment facilities are designed to add clean water to belt filter press, additional water is needed. Therefore, it is necessary to improve belt filter press in order to decrease the extra water. Finally, although large-scale organic fertilizer plants and resources recycling centers produce good organic (liquid) fertilizers with proper components, it is necessary to establish standards for maturity of liquid fertilizers in order to facilitate efforts to turn livestock manure into resources.

• 센서학회지
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• 제32권3호
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• pp.140-146
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• 2023

Water quality is crucial for human health and the environment. Accurate measurement of the quantity of organic carbon in water is essential for water quality evaluation, identification of water pollution sources, and appropriate implementation of water treatment measures. Total organic carbon (TOC) analysis is an important tool for this purpose. Although other methods, such as chemical oxygen demand (COD) and biochemical oxygen demand (BOD) are also used to measure organic carbon in water, they have limitations that make TOC analysis a more favorable option in certain situations. For example, COD requires the use of toxic chemicals, and BOD is time-consuming and can produce inconsistent and unreliable results. In contrast, TOC analysis is rapid and reliable, providing accurate measurements of organic carbon content in water. However, common methods for TOC analysis can be complex and energy-intensive because of the use of high-temperature heaters for liquid-to-gas phase transitions and the use of acid, which present safety risks. This study focuses on a TOC analysis method using TiO₂ photocatalysis, which has several advantages over conventional TOC analysis methods, including its low cost and easy maintenance. For TiO₂, rutile and anatase powders are mixed with an inorganic binder and spray-coated onto a glass fiber substrate. The TiO₂ powder and inorganic binder solutions are adjusted to optimize the photocatalytic reaction performance. The TiO₂ photocatalysis method is a simple and low-power approach to TOC analysis, making it a promising alternative to commonly used TOC analysis methods. This study aims to contribute to the development of more efficient and cost-effective approaches for water quality analysis and management by exploring the effectiveness and reliability of the developed equipment.