• Korean Journal of Weed Science
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• v.8 no.1
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• pp.1-8
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• 1988

In order to get basic information for establishing weed control methods, weed distribution was surveyed at 15 days interval in garlic and red pepper fields at 8 locations in Chungnam Province. In garlic fields, 68 weed species(27 families) were distributed. Portulaca oleracea, Chenopodium album and Digitana sanguinalis were most dominant and Equisetum arvense, Alopecurus aequalis, and Setaria viridis dominant among them. Highest number of weeds emerged in May and dry weight or weeds was more heavy in June and summer broadleaf weeds were most abundant throughout garlic growing period. In red pepper fields, 38 weed species(17 families) were distributed, D. sanguinalis, Cyperus amuricus and P. oleracea were most dominant and Echinochloa crus-galli, Eleusine indica, D. violascens, and Centipeda minima also dominant among them. The highest number of weeds were emerged in June and summer, grasses and summer broadleaf weeds were more abundant in June and July. Seasonal Shannon's diversity index(H'), maximum diversity(Hmax') and eveness(J') for the Shannon diversity index, and Simpson index were high in both red pepper and garlic fields. Interspecific competition(probability for interspecific encounter) was more severe than intraspecific competiton.

• Korean journal of food and cookery science
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• v.10 no.1
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• pp.45-50
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• 1994

Conventional Doenjang, three kinds of Improved Doenjang(A; koji: soybean: salt=53: 100: 33, B; koji: soybean: salt=100: 100: 40, C; koji: soybean: salt= 200: 100: 40) prepared with different ratio of koji and salt were made to study the changes in the general contents, characteristics bitter peptides, correlations between bitterness and overall eating quality. 1. Total nitrogen contents increased a little, and amino nitrogen contents in all samples increase markedly. Especially, Amino nitrogen contents of conventrional Doenjang increased more than others. Reducing sugars of doenjang prepared with Asp. oryzae were higher than conventional Doenjang and increased throughout the aging period and Doenjang prepared with Asp. oryzae were more acidic. 2. To characterize bitter peptides in fermented Doenjang, peptides were extracted with 2: 1(v/v) chloroform-methanol and separated by Gel chromato-graphy with Sephadex and TLC. After Gel chromatography and TLC, each fraction examined presence of bitterness and evaluated intensity of bitterness. Amino acid composition of the fractions showing bitter tastes were as follows. Conv. peak 1-1 Trp-(Asp, Arg, Thr, Ser, Glu, Pro)-Phe Imp. A peak 1 Trp-(Glu, Val, Arg, lie)-Phe Imp. B peak 1 Trp-(lie, Pro, Asp, Lys, Val, Glu)-Trp. Imp. C peak 1-2 Trp-(Try, Thr, Glu, Pro, Gly)-Phe 3. Sensory evaluation revealed that correlation coefficient between bitterness and overall eating guality was not high.

• Journal of agriculture & life science
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• v.44 no.5
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• pp.117-127
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• 2010

The purpose of this study is to analyze the temporal and spatial characteristics of water quality data of Nakdonggang watershed which is second largest watershed in South Korea. The correlation between the water quality items for rainy and non-rainy seasons were also analyzed for two TMDL sites which are Gumi and Namji. BOD data of two Total Maximum Daily Loads (TMDL) target sites were compared with TMDL criteria, 3-year arithmetic mean BOD concentration of the target sites should not exceed the target concentration for 2 consecutive years, to figure out current water quality status. Spatial analysis results showed that the correlation coefficient between Goryeong and Hyunpung was highest with the value of 0.978 followed by Hapcheon and Namji with the value of 0.874. The observed BOD data of Gumi station fluctuated around the TMDL criterion, 1.8mg/L while Namji station mostly exceed the criterion, 2.6mg/L. The criteria values for each target sites are defined by Ministry of Environment. The major factor of correlation coefficient was the distance between the stations. The correlation between the water quality items for non-rainy season showed no relation while the correlation between COD and SS was high followed by COD and TP for Gumi and Namji.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.31 no.1
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• pp.52-70
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• 2018

Objectives : Atopic dermatitis(AD) and environmental factors are closely related, but there is lack of oriental medical examination. So we compared the relationship between AD and various environmental factors in Oriental medicine and Western medicine. Methods : We described the relationship between AD and environmental factors through the latest papers and a review of the oriental medicine literature. Results : The regional diversity of AD incidence implies a close relationship between climate factors and AD, and high altitude and low pH springs also have an effect on AD. Air pollutants from industrialization and urbanization aggravate AD. The increase in indoor residence time and the increase in room temperature and humidity have also increased the sensitization to allergens such as house dust mite. In oriental medicine, wind(風) is one of the environmental factors and is an inflammatory state due to external irritation. Wind-Humidity(風濕) refers to erythematous wetting dermatitis with itching and exudation, Wind-Fever(風熱) refers to acute inflammatory reaction with erythematous papules and plague, and Blood-Weakness(血虛) refers to aggravation and chronicization of inflammation due to persistence of skin barrier impairment. Conclusions : We examined the relationship between AD and various environmental factors. We also described the oriental medical viewpoints of the environmental factors in the occurrence of AD and skin barrier impairment.

• Korean Journal of Soil Science and Fertilizer
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• v.8 no.4
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• pp.171-176
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• 1975

The rate and extent of decomposition of rice straw and compost in an acid sulfate soil amended with urea and lime and incubated under aerobic and anaerobic(flooded) conditions were investigated in the laboratory. Results are summarized as follows: 1. The rate of compost(alone) decomposition in a flooded soil was more than twice as high as all other treatments, which included rice straw+urea, rice straw+lime, rice straw (alone), and compost+lime. Lime appeared to suppress the decomposition of compost in a flooded soil but actually enhanced its decomposition under aerobic conditions. 2. Compost decomposition in both anaerobic and aerobic environments was characterized by single maximum peak rates of $CO_2$ evolution that were reached soon after the start of incubation. 3. Both urea and lime greatly increased the rate and extent of rice straw decomposition in the soil when incubated aerobically, although urea had a greater effect than did liming. Decomposition rates were characterized by the appearance of two maximum peak rates, a greater primary peak and a smaller secondary peak. 4. The percent decomposition of rice straw in soil incubated aerobically was approximately half (10.8%) that of compost(23.1%). However, percent decomposition of these substrates in soil amended with lime was essentially the same; i.e., rice straw+lime (29.4%) and compost+lime(31.6%). 5. There is a need to investigate the possible interaction between the addition of lime (pH) and supplemental nitrogen applied to acid sulfate soils and how this interaction might affect the decomposition of organic wastes and residues.

• Korean Journal of Soil Science and Fertilizer
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• v.21 no.1
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• pp.49-54
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• 1988

The present experiment was conducted to investigate causes affecting the reduction of red pepper production in the continuous cultivation upland soil from 1985 to 1986 in Imsil Chonbuk Province. The results obstained are summarized as follows: 1. Area ratio of continuous cultivation 2 years was 12.7%, 3 years 6.8% and over 4 years 48.9%. 2. Soil hardness and volume of solid and liguid of red pepper continuous cultivation soil were higher than those of one year cultivation, while pH and content of organic matter of continuous cultivation soil were low. The exceeding optimum level of phosphorus and potassium appeared factors affecting and reduction of red pepper of continuous cultivation soil. 3. Microflora density in continuous cultivation soil was high but bacteria/fungi (B/F) and actinomycetes/fungi (A/F) ratio were low. 4. The density of soil nematodes in continuous cultivation soil were higher than that in one year cultivation soil, however, the steeper and better drainage soil lowered the density of nematodes. 5. Continuous cultivation over 4 years showed 14.3% of plants diseased by phytophthora while 0.7% in one year cultivation soil.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.6
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• pp.1063-1070
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• 2011

In this study, total of 5 different chemical amendments were evaluated for determining kinetic parameters and stabilization efficiency of heavy metals in aqueous phase. Standard solution of Cd and Pb ($100mg\;L^{-1}$) was mixed with various ratio of amendments (1, 3, 5, 10%) and heavy metal stabilization efficiency was monitored for 24hrs. All examined amendments showed over 90% of removal efficiency for both Cd and Pb except zerovalent iron (ZVI) for Cd (43-63%). Based on result of heavy metal stabilization efficiency, it was ordered as $CaCO_3$ > Dolomite > Zeolite > Steel slag > ZVI for both Cd and Pb in aqueous phase. For kinetic study, first order kinetic model was adapted to calculate kinetic parameters. In terms of reaction rate constants (k), zeolite showed the fastest reaction rate (k value from 0.4882 for 1% to 2.0105 for 10%) for Cd and ZVI (k value from 0.2304 for 1% to 0.5575 for 10%) for Pb. Considering reaction rate constant and half life for heavy metal stabilization, it was ordered as Zeolite > $CaCO_3$ > Dolomite > Steel slag > ZVI for Cd and $CaCO_3$ > Dolomite > Steel slag > Zeolite > ZVI for Pb. Overall result in this study can be interpreted that lime containing materials are more beneficial to remove heavy metals with high efficiency and less time consuming than absorbent materials.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.6
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• pp.776-781
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• 2010

Estimating the electrical conductivity of the saturation-paste (SP) is a common method to assess soil salinity. To assess soil salinity realistically, it is important to extract soil solution under field capacity. However, few studies on salinity assessment have been conducted for soil solution extracted under field capacity (-33 kPa; FC) moisture condition due to difficulty in soil solution extraction. This study was conducted to evaluate whether saturation-paste can represent field condition. Soil solutions were extracted from 22 soils in the plastic film house (PFH) and 18 soils in the reclaimed land (RL) at saturation and field capacity moisture conditions. Those were analyzed for pH, EC, cations ($K^+$, $Ca^{2+}$, $Mg^{2+}$, $Na^+$) and anions ($Cl^-$, ${NO_3}^-$, ${PO_4}^{3-}$, ${SO_4}^{2-}$). Both cations and anions of soil solution extracted from FC showed high correlations with ions extracted from SP in the PFH and the RL, except for ${NO_3}^-$, ${PO_4}^{3-}$ in the RL. Results of the t-test, the ECe and $EC_{FC}$ were not significant at significance level 0.05. The slopes of the equations between $EC_{FC}$ and ECe at more than sand 50% soils were higher than less than sand 50% soils, and differences of saturation percentage between SP and FC showed larger as increasing sand percentage. EC was related to soil water retention by soil texture. To determine the EC, soil texture and other soil properties which effect the soil moisture should be considered.

• Korean Journal of Food Science and Technology
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• v.53 no.5
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• pp.593-600
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• 2021

In this study, the vacuum distillation process for producing non-alcoholic red wine was optimized via response surface methodology. As a result of optimizing the responses (alcohol content, yield) for independent variables (operating time, boiling point, and temperature difference), 1% alcohol content and 81.15% yield were obtained at an operating time of 24.5 min, boiling point of 65℃, and temperature difference of 8℃. To investigate the physicochemical and sensory properties, non-alcoholic wines with different boiling points (bp 25℃, bp 45℃, and bp 65℃) and a blended wine (4.2% of control wine added) were prepared. As the boiling point increased, the alcohol content decreased, and CI (color intensity) and Hue increased. Blended wine exhibited the highest value and bp 65℃ showed the lowest value in terms of sensory properties. In conclusion, distillation at a low boiling point and blending control wine could be used to prepare non-alcoholic wine with a high preference.

• Current Photovoltaic Research
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• v.9 no.3
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• pp.75-83
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• 2021

The tunnel oxide passivated contact (TOPCon) structure got more consideration for development of high performance solar cells by the introduction of a tunnel oxide layer between the substrate and poly-Si is best for attaining interface passivation. The quality of passivation of the tunnel oxide layer clearly depends on the bond of SiO in the tunnel oxide layer, which is affected by the subsequent annealing and the tunnel oxide layer was formed in the suboxide region (SiO, Si₂O, Si₂O₃) at the interface with the substrate. In the suboxide region, an oxygen-rich bond is formed as a result of subsequent annealing that also improves the quality of passivation. To control the surface morphology, annealing profile, and acceleration rate, an oxide tunnel junction structure with a passivation characteristic of 700 mV or more (V_oc) on a p-type wafer could achieved. The quality of passivation of samples subjected to RTP annealing at temperatures above 900℃ declined rapidly. To improve the quality of passivation of the tunnel oxide layer, the physical properties and thermal stability of the thin layer must be considered. TOPCon silicon solar cell has a boron diffused front emitter, a tunnel-SiO_x/n⁺-poly-Si/SiN_x:H structure at the rear side, and screen-printed electrodes on both sides. The saturation currents J_o of this structure on polished surface is 1.3 fA/cm² and for textured silicon surfaces is 3.7 fA/cm² before printing the silver contacts. After printing the Ag contacts, the J_o of this structure increases to 50.7 fA/cm² on textured silicon surfaces, which is still manageably less for metal contacts. This structure was applied to TOPCon solar cells, resulting in a median efficiency of 23.91%, and a highest efficiency of 24.58%, independently. The conversion efficiency of interdigitated back-contact solar cells has reached up to 26% by enhancing the optoelectrical properties for both-sides-contacted of the cells.