• Proceedings of the Korea Air Pollution Research Association Conference
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• 2001.11a
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• pp.303-304
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• 2001

주 구성요소가 산소와 질소 기체인 대기는 백색광을 지닌 광원, 즉 태양광에 대하여 선택적으로 빛을 산란시킴으로써 파란색을 나타낸다. 이것은 Rayleigh scattering 효과가 파장의 4승에 반비례하기 때문에 450nm 부근의 파란색은 700nm 부근의 빨간색에 비하여 약 6배이상 강한 빛을 산란시키기 때문이다. 그러나 실제로 하늘은 고정된 색을 지니고 있지는 않다. 태양과 관측자 및 관측지점의 유기적 관계에 의하여 하늘의 색은 주기적이며 임의적으로 다르게 보인다. (중략)

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2001.11a
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• pp.367-368
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• 2001

휘발성 유기화합물질들(VOCs)은 그 자체가 인체에 유해한 화합물로 작용할 뿐만 아니라 환경대기 중에서 질소화합물(NOx)과 광화학 반응을 통하여 오존 등 유해한 산화물을 형성하는 전구물질로 작용하여 이들의 거동을 이해하고 분석하는 것이 대기환경에 매우 중요한 것으로 인식되고 있다. 더욱이 오존 예보 및 경계 체제의 중요한 입력 요인으로 인식되어 신뢰성 있는 배출 정보의 산출을 위해 VOCs 농도를 현장 실측하여 분석하고 예보에 이용하려는 시도가 이루어지고 있다. (중략)

• Korean Journal of Food Science and Technology
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• v.29 no.2
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• pp.211-217
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• 1997

The physical and chemical stability of anthocyanins from a Korean pigmented rice variety was investigated at various conditions of pH, temperature, metal ion, sugar, organic acid and light. The anthocyanin pigments were relatively stable with half-lives of 36 days (pH 2.0) and 17 days (pH 3.0), while they were decomposed in a day at neutral and basic pH of 7.0 and 9.0 at $25^{\circ}C$. The anthocyanins also showed high thermal stability at pH 3.0; the half-lives were 7.4 hr, 23.6 hr and 96.3 hr at $95^{\circ}C,\;75^{\circ}C\;and\;50^{\circ}$, respectively. Addition of di- and tri-valent metal ions at pH 3.0 resulted in the increase of color intensity and stability throughout 21 days of storage periods at $25^{\circ}C$. Most sugars added accelerated the degradation of anthocyanin pigments, so that fructose showed the greatest degradation effect on the pigments. Addition of citric acid at pH 3.0 increased stability of anthocyanins, while tartaric acid decreased stability. The anthocyanins were very sensitive on light irradiation with a degradation half-life of 14 hr under 20,000 lux-light dosage at pH 3.0.

• The Korean Journal of Food And Nutrition
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• v.25 no.3
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• pp.505-512
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• 2012

This study evaluated the quality characteristics of rice-doenjang prepared with Aspergillus oryzae MD05 and Bacillus subtilis HJ18-4. The physicochemical characteristics of rice-doenjang prepared with three types of meju, such as grain type(Rice 1), disc shape(Rice 2), and brick shape(Rice 3), were compared. We determined amino and ammonia nitrogen contents, protease and amylase activities, reducing sugar content, and total aerobic counts and lactic acid bacteria counts. The amino nitrogen and reducing sugar contents in all meju types gradually increased during fermentation. The amino nitrogen contents reached 151.5~200.0 mg%. Rice 3 were had the highest levels among the 4 types of rice-doenjang. After 42 days of fermentation, amylase and protease activity of Rice 3 were 366.57 and 94.26 unit/g, respectively, which were the highest levels among the 4 types of rice-doenjang. The total aerobic bacteria counts were not changed during 42-day fermentation. This results suggest that high quality characteristics of brick-shaped meju(Rice 3) were better than those of the other meju preparations.

• Korean Journal of Organic Agriculture
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• v.10 no.1
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• pp.49-63
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• 2002

In order to supply 85% of total organic feed in ruminants and 80% in non-ruminants for organic animal production, nitrogen fixation ability of legume should be used in domestic roughages production. 50% of Europe organic farmer use intercropping legume in as green manure. This article is dealing with amount of biologically fixed nitrogen used by legumes and methods for estimating the transfer of biologically fixed N in rotation and separating the N benefit into fixed N and non-fixed N components are reviewed. Available data indicate that transfer amount of N to non legumes was from 50∼9.6(kg/ha) in legume-cereal rotations and proportion of legume N varied with seasons, 90% in summer, 50% in autumn. The important point in cropping system for legumes have to be included for organic forage production 6 year rotation is based on pasture system of 3 year pasture + 2 year annual(com, sudangrass), again pasture. Rye, barly and Italian ryegrass+legumes(vetch, crimson and pea) can be one of option in spring, com, soybean, sudangrass and Japanese bamyard millet would be seeded after spring harvest in the field. Farmer can make good use of rice paddy field as forge production potential area after harvesting rice. Italian, burly and rye+vetch and crimsonclover may be grown in autumn or spring time at the rice field.

• Applied Chemistry for Engineering
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• v.29 no.1
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• pp.1-9
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• 2018

Microalgae is considered as one of environmentally sustainable and potential feedstocks to produce biodiesels. However, recent studies on life cycle assessments (LCA) of microalgal buidiesels have shown that energy requirement is not small to produce biodiesel from microalgae, especially during cultivation stage. The costs for carbon sources, nutrients like nitrogen or phosphorous, and water for cultivation can contribute up to 80% of the total medium costs. In the present article, recent trends on the utilization of several promising nutrient sources such as municipal wastewaters, organic fertilizers, combustion exhaust emissions and organic solid wastes were reviewed, and the potential strategies to be used as substitutes of artificial culture media, especially for the biodiesel production, were discussed.

• Korean Journal of Organic Agriculture
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• v.25 no.4
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• pp.805-819
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• 2017

The study was carried out to develop a mathematical model for evaluating the effect of organic fertilizers in organic rice production systems. A function to simulate the nitrogen mineralization process in the paddy soil has been developed and integrated into ORYZA2000 crop growth model. Inorganic nitrogen in the soil was estimated by single exponential models, given temperature and C:N ratio of organic amendments. Data collected from the two-year field experiment were used to evaluate the performance of the model. The revised version of ORYZA2000 provided reasonable estimates of key variables for nitrogen dynamics and crop growth in the organic rice production systems. Coefficient of determination between the measured value and simulated value were 0.6613, 0.8938, and 0.8092, respectively for soil inorganic nitrogen, total dry matter production, and rice yield. This means that the model could be used to quantify nitrogen supplying capacity of organic fertilizers relative to chemical fertilizer. Nitrogen dynamics and rice growth simulated by the model would be useful information to make decision for organic fertilization in organic rice production systems.

• 한국생물공학회:학술대회논문집
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• 2002.04a
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• pp.361-364
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• 2002

BAC (biological activated carbon) process is a combination of biodegradation and active carbon adsorption. Pre-ozonation of raw water increased in biodegradable organic fraction. This study is to investigate the enhancement of dissolved organic matter removals by pre-ozonation process combined with BAC process at a semi-pilot scale. By biodegradation improvement in pre-ozonation process. the charge of adsorption was reduced and the life of biological activated carbon is extended. And, 48 % of total DOC was remove in the upper compartment of BAC column. The removal of the nitrogen-ammonia shows a considerably high removal ratio with 75.9 %.

• Journal of Soil and Groundwater Environment
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• v.8 no.2
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• pp.70-77
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• 2003

Theoretical estimation of overall stoichiometry for the microbial degradation of hazardous organic compounds is described. Half-reaction method based on microbial energetics was used in the theoretical estimation. In addition to the half-reaction method, other theoretical methods such as intermediate formation, oxygenation reaction, and estimation of the standard free energy of formation by group contribution theory were also applied. As a case study, the application of these methods was demonstrated for the estimation of microbial kinetics in the biodegradation of phenanthrene which was chosen as a model hazardous organic compound along with glucose and hexadecane. The cell yield, oxygen requirement, nitrogen requirement, and mineralization ratio could be estimated from the overall stoichiometry. It is believed that these theoretical estimation methods are useful tools for practical design and assessment of bioremediation of soil and groundwater contaminated with hazardous organic compounds.

• Journal of the Korean Vacuum Society
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• v.17 no.5
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• pp.455-460
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• 2008

In recent years, there has been highly interestedin pulsed laser deposition (PLD) method for fabrication of the organic thin films, as an alternative to conventional fabrication method such as vacuum evaporation and spin coating techniques. In this study, organic thin films of $Alq_3$ (aluminato-tris-8-hydroxyquinolate) and TPD for organic light emitting diodes (OLED) were deposited by PLD using KrF excimer ($\lambda$=278 nm) laser in nitrogen atmosphere. Deposited films were evaluated by photoluminescence(PL), Fourier-transform Infrared Spectroscopy (FT-IR) to study the effect of the laser and $N_2$ atmosphere parameters on the structural and optical properties.