• Korean Journal of Soil Science and Fertilizer
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• v.49 no.6
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• pp.651-654
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• 2016

A number of accidents relating to highly toxic hydrogen fluoride (HF) or hydrofluoric acid (HA) release have occurred over fast few decades in Korea. Thus, this study was conducted to investigate the fluoride (F) concentrations in paddy soil and brown rice from 2 different areas where the soils were exposed to HF and HA. In the first case, the HF leakage accident that occurred in 2012 affected the surrounding soils and crops and consequently, crops (rice) affected by HF were unavailable for forage even though F did not accumulate in the soil. For example, at the time of accident, F concentrations in brown rice samples were $33.0-1,395mg\;kg^{-1}$, while F concentrations in soil samples were $155-295mg\;kg^{-1}$ which were less than the Korean standard guideline values of $400mg\;kg^{-1}$. However, after a year, F concentrations in brown rice were observed below the detection limit ($1mg\;kg^{-1}$), although F concentrations in soils were similar with those in 2012. Also, large amounts of wastewater discharges containing HA occurred in 2013 and some agricultural soils exceeded the Korean standard guideline values for F ($400mg\;kg^{-1}$), but soil-plant F transfer was not observed. In conclusion, it was observed that soil to plant transfer of F is unlikely although HF and HA as gas or liquid form can cause direct damage to plants.

• Korean Journal of Food Science and Technology
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• v.49 no.6
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• pp.632-637
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• 2017

This study was conducted to determine the minimal processing characteristics of four vegetables (brown mustard, kale, red beet and red lettuce) for wrapping (Ssam). Prior to evaluation, the vegetable leaves were cut, washed, and packaged. The texture, weight loss, browning index, pH, gas concentrations ($O_2$ and $CO_2$), microbial growth, and organoleptic qualities of the leaves were assessed at $10^{\circ}C$ for 7 days. The cutting strength of red beet was significantly different among leaves. The initial springiness of brown mustard was the lowest (0.98%). The weight loss varied between 0.24 to 4.77%, pH ranged from 6.00 to 6.95, and browning index increased to 0.95 during storage. Changes of gas composition were lower in cut leaf than whole leaf. Aerobic bacteria (4.9-8.0 log CFU/g), yeast (not detected), mold (-3.5 log CFU/g), and total coliforms (5.0-8.0 log CFU/g) were assessed in the samples. Thus, overall quality of kale and red beet leaves with minimal processing showed satisfactory results when stored for 7 days.

• Korean Journal of Poultry Science
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• v.30 no.1
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• pp.61-66
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• 2003

This study was conducted to investigate the effects of dietary germanium biotite supplementation on egg quality and fecal noxious gas content in laying hens. One hundred and forty-four 40-wk-old, ISA Brown layers were used in this experiment. Dietary treatments were 1) CON(control diet), 2) GB0.5(control diet + 0.5% germanium biotite), 3) GB1.0 (control diet + 1.0% germanium biotite) and 4) GB1.5(control diet + 1.5% germanium biotite). Hen-day egg Production and egg shell breaking strength were not influenced by germanium biotite supplementation. However, egg weight decrease as the level of germanium biotite supplementation increased in the diets increased(Cubic effect, p<0.02). Eggshell thickness, yolk color and yolk index were not influenced by garmanium biotite supplementation. Serum triglyceride concentration as dietary germanium biotite increased (linear effect P<0.02; quadratic effect, p<0.05). Dietary supplementation of germanium biotite reduced fecal NH$_3$-N concentration (P<0.01), propionic acid(P<0.01), butyric acid( P<0.05) and acetic aicd(P<0.01) concentrations in the feces. In conclusion, the results of this experiment indicated that dietary germanium biotite supplementation did not affect egg shell quality, but reduced fecal NH$_3$-N concentration.

• Korean Journal of Environmental Agriculture
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• v.1 no.2
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• pp.123-128
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• 1982

This study was carried out to investigate the effect of ozone gas on paddy rice at the different growth stage. Seokwang variety of rice plant was exposed to 0.5 ppm ozone gas for 4 hours at rooting, maximum tillering, ear formation and heading stages. after ozone gas fumigation, damage symptom, percentage of destroyed leaf, chlorophyll content and peroxidase activity of rice plant were observed. The results obtained are as follows. 1) Typical symptom of ozone gas damage appeared greyish or reddish brown subtle spots within rice leaf vein. 2) Yield loss by ozone gas exposure at different growth stage was in the order of maximum tillering stage>rooting stage>ear formation stage>heading stage. 3) Chlorophyll damage and leaf destruction was the highest at maximum tillering stage, while damage of leaf and chlorophyll were not found at heading stage. 4) The damage by ozone gas fumigation was higher at the growth stage with higher N content in plant, and N content was decreased after ozone gas exposure.

• Journal of the Korean institute of surface engineering
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• v.34 no.5
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• pp.384-390
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• 2001

The hollow cathode discharge is a kind of plasma formation scheme in which plasma is formed inside a hollow structure, the cathode, with current to a nearby anode of arbitrary shape. In this scheme, electrons reflex radially within the hollow cathode, establishing an efficient ionization mechanism for gas within the cavity. An existence condition for the hollow cathode effect is that the electron mean-free-path for ionization is of the order of the cavity radius. Thus the size of this kind of plasma source must decrease as the gas pressure is increased. In fact, the hollow cathode effect can occur even at atmospheric pressure for cathode diameters of order 10-100 $\mu\textrm{m}$. That is, the "natural" operating pressure regime for a "micro hollow cathode discharge" is atmospheric pressure. This kind of plasma source has been the subject of increasing research activity in recent years. A number of geometric variants have been explored, and operational requirements and typical plasma parameters have been determined. Large arrays of individual tiny sources can be used to form large-area, atmospheric-pressure plasma sources. The simplicity of the method and the capability of operation without the need for the usual vacuum system and its associated limitations, provide a highly attractive option for new approaches to many different kinds of plasma applications, including plasma surface modification technologies. Here we review the background work that has been carried out in this new research field.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2002.04a
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• pp.73-76
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• 2002

Biofilter performance to reduce C $H_4$ emissions from MSW landfills was tested under a variety of environmental and design conditions. The optimum soil moisture content for C $H_4$ oxidation in a loamy sand was 13% by weight. The addition of N $O_3$-N did not affect the C $H_4$ oxidation rate. Soil depths of 30cm and 60cm were equally efficient in C $H_4$ oxidation. When the C $H_4$ loading rate was decreased, the percentage of C $H_4$ oxidized increased. The maximum C $H_4$ oxidation rate was 27.2 mol $m^{-2}$ $d^{-1}$ under optimum conditions (loamy sand soil, 13% moisture content, 30cm soil depth, and an loading rate of 32.8 mol $m^{-2}$ $d^{-1}$). Based on the above results, the installation of a properly sized and managed biofilter above a landfill cover should be capable of achieving a major reduction in atmospheric methane emissions from MSW landfills built with RCRA covers.

• Journal of Hydrogen and New Energy
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• v.35 no.2
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• pp.175-184
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• 2024

This study focuses on investigating the importance of managing greenhouse gas emissions from global energy consumption, specifically examining domestic targets for clean hydrogen production. Using life cycle assessment, we evaluated reductions in global warming potential and assessed the carbon neutrality contribution of the domestic hydrogen sector. Transitioning from brown or grey hydrogen to blue or green hydrogen can significantly reduce emissions, potentially lowering CO₂ equivalent levels by 2030 and 2050. These research findings underscore the effectiveness of clean hydrogen as an energy management strategy and offer valuable insights for technology development.

• Journal of the Korean Society of Food Science and Nutrition
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• v.16 no.1
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• pp.29-35
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• 1987

The compositional characteristics of polar lipids in the brown and polished adlay were studied. Total lipids of brown and polished adlay were extracted, purified and fractionated into neutral and polar lipids by silicic acid column chromatography. The glycolipid(GL) and phospholipid(PL) of polar lipids were seperated by thin layer chromatography and quantitated by scanner. The fatty acid composition in polar lipids were determined by gas chromatographr. The contents of GL and PL in brown adlay were 5.67% and 1.83%, and their contents on polished adlay were 5.49% and 1.78%, respectively. Of the GL in the brown and polished adlay, monogalactosyl diglycerides+esterified steryl glycosides and digalactosyl diglycerides were the major components, but cerebrosides+steryl glycosides were also found as the minor component of GLs. Of the PLs, phosphatidyl choline and phosphatidyl ethanolamine were the major components. Phosphatidyl inositol, lysophosphatidyl choline and phosphatidyl serine were also present in the PLs. The major fatty acids of GLs were linoleic, oleic and palmitic acids. The fatty acid composition in the PLs were similar to the pattern in the GLs, but PLs contained the lower percentage of linoleic acids than the GLs.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.10 no.4
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• pp.199-204
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• 1977

The patterns of fatty acid composition of lipid extracted from eight species of edible marine benthic algae; i. e. two species of green, five of brown and one of red algae, were investigated quantitatively by using gas liquid chromatography. The total lipid contents in average of the algae were $1.51\%$ in the green algae, $2.81\%$ in brown algae and $1.02\%$ in red algae respectively. Upon analyzing fatty acid composition, green algae contained the highest proportion of $C_{16:0}$ acid and comparatively higher content of $C_{18:1},\;C_{18:2}\;and\;C_{18:3}$ acids than the other algae. In brown angae, $C_{16:0}$ acid content was highest, but not more than that of green algae, and $C_{14:0},\;C_{18:1}$ acids were higher than other $C_{16:1},\;C_{18:2}\;and\;C_{18:3}$ acids while the content of $C_{18:0}$ acid was very low. Red algae showed low content of $C_{14:0},\;C_{18:1},\;C_{18:2}\;and\;C_{18:3}$ acids, but the content of $C_{16:0}$ acid was high as a major component. In regard to the composing patterns of carbon number of fatty acid of algae; i. e. $C_{14},\;C_{15},\;C_{16},\;C_{18}\;and\;C_{22}$ and $C_{22}$ acids, the green algae contained $C_{16}$ and $C_{18}$ acids, the brown algae $C_{16},\;C_{18},\;and\;C_{22}$ and $C_{22}$ acids, and the red algae $C_{15},\;C_{16}$, and $C_{18}$ acids as the major component.

• Animal Bioscience
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• v.34 no.11
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• pp.1802-1810
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• 2021

Objective: The purpose of this study was to evaluate the effects of supplementing herbal active ingredients (YGF251) which can promote the secretion of insulin-like growth factor-1 (IGF-1) in the diet on production performance, egg quality, blood hematology, and excreta gas emission in laying hens. Methods: A total of 288 ISA Brown (41-week-old) laying hens with an initial body weight of 1.83±0.68 kg were randomly assigned to 1 of 4 dietary treatments in a randomized block design based on body weight. Each treatment had 12 replicate cages having 6 adjacent cages per replicate (hens are kept in cages alone). The experimental period was 35 days. Dietary treatments were based on the corn-soybean meal-wheat-based basal diet and supplemented with 0.00%, 0.05%, 0.10%, or 0.15% YGF251. Results: There was a linear increased egg weight in weeks 1 to 5 (p<0.05), egg mass in week 1 (p<0.05) and weeks 1 to 5 (p<0.05), egg strength on day 7 (p<0.05), 21 (p<0.01), and 35 (p<0.01), eggshell thickness on day 21 (p<0.05) and 35 (p<0.01), haugh unit on day 21 (p<0.01) and 35 (p<0.05), serum IGF-1 concentration on day 21 (p<0.05) and 35 (p<0.01), and serum total protein concentration on day 35 (p<0.05) were observed with the supplementing YGF251 increased in the diet, while feed conversion ratio in weeks 1 to 5 (p<0.05) and excreta ammonia emission (p<0.01) decreased linearly with the dose of YGF251 increased. Conclusion: Dietary supplementation of YGF251 positively affected the production performance and egg quality of laying hens through increasing serum IGF-1 concentration in a dose-dependent manner. Moreover, YGF251 supplementation improved barn environment by reducing excreta noxious gas emission.