• Journal of Korean Society of Environmental Engineers
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• v.27 no.6
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• pp.642-650
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• 2005

This research investigates the effects of adding oxidants such as $Fe^0$, $Fe^{2+}$, and ${S_2O_8}^{2-}$ in the sonolysis of 1,4-D. Results indicate that the degradation could be divided into two steps (initiation and acceleration) kinetically. The initial portion agreed with zero-order expression, while the second portion could be fitted with pseudo first-order expression. In the presence of ${HCO_3}^-$, as a radical scavenger, the degradations of 1,4-D and TOC were suppressed, indicating that OH radical is an important factor in the sonolysis. The overall degradation efficiency of 79.0% in the sonolysis was achieved within 200 minutes. While $Fe^0$, $Fe^{2+}$, and ${S_2O_8}^{2-}$ were individually combined with sonication, the degradation efficiency of 1,4-D increased 18.6%, 19.1%, and 16.5% after 200 min, respectively. The addition of oxidants not only changed the kinetic model from zero to pseudo first order at initiation step, but also increased the rate constants in the acceleration step. The addition of oxidants in the sonolysis of 1,4-D also improved the mineralization of 1,4-D, however, the effect of adding oxidants on the rate increase was similar regardless of the oxidants.

• Culinary science and hospitality research
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• v.19 no.5
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• pp.49-58
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• 2013

The principal objective of this study was to understand the quality characteristics of kimchi added with anchovy sauce from heat and non-heat treatments. The kimchi made through such treatments contained 1.1% or 1.3% of salinity and 4.05 or 4.16 of pH. Generally, the kimchi with anchovy sauce from non-heat treatment contained higher Ca and Fe values than the one with anchovy sauce from heat treatment did. However, P, Zn, Na values were higher in the kimchi with anchovy sauce from heat treatment. Also, measurement of total-microbial, Lactobacillus sp. and Leuconostoc sp. from kimchi after filtration of anchovy sauce from heat treatment showed $5.2{\times}10^6$, $1.3{\times}10^8$, and $2.1{\times}10^8$ CFU/mL, respectively. In addition, kimchi after filtration of anchovy sauce from non-heat treatment showed $8.3{\times}10^6$, $2.5{\times}10^7$, and $1.6{\times}10^7$ CFU/mL, respectively. The present results help understand chemical compositions of kimchi and encourage its application for the food industry and cooking.

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 2000.11a
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• pp.113-117
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• 2000

경량 건축소재는 건축자재의 경량화, 고급화 및 다양화 등의 기능성 건축소재로의 역할을 요구하고 있으며 그 중 대표적인 것으로는 polyurethane foam이 있다 일반적인 플라스틱 foam의 경량 건축소재는 난연성에 대한 문제점과 첨가제에 의한 중량 증가, 화재 발생시 과다연기발생 등의 문제점이 있으며 저밀도 콘크리트 등의 무기소재는 flexibility가 떨어져 충격과 휨강도가 매우 낮은 단점을 가지고 있다.(중략)

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 2001.11a
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• pp.343-346
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• 2001

경량 건축소재는 건축자재의 경량화, 고급화 및 다양화 등의 기능성 건축소재로의 역할을 요구하고 있으며 그 중 대표적인 것으로는 polyurethane foam이 있다. 일반적인 플라스틱 foam의 경량 건축소재는 난연성에 대한 문제점과 첨가제에 의한 중량 증가, 화재발생시 과다연기발생 등의 문제점이 있으며 저밀도 콘크리트 등의 무기소재는 flexibility가 떨어져 충격과 휭강도가 매우 낮은 단점을 가지고 있다./sup 1.2)/ 열경화성 수지인 polyurethane도 난연성과 강도에 대한 단점을 가지고 있어 sodium silicate 혼합에 의한 난연성을 향상시킬 수 있으나/sup 3)/ 국내 난연 3급의 규격에도 미치지 못하는 특성을 가지고 있다.(중략)

• Proceedings of the Optical Society of Korea Conference
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• 2005.02a
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• pp.280-281
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• 2005

• Korean Journal of Food Science and Technology
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• v.35 no.1
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• pp.149-154
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• 2003

Changes in mineral (Ca, Mg) contents and pectic substances of mature-green 'Nanko' Mume fruits hermetically packaged in 0.03 mm low density polyethylene (LDPE) films with and without gas absorbents were examined during storage at $25^{\circ}C$ for 10 days. Each packaging contained 10 g $Ca(OH)_2$ as a carbon dioxide scavenger, 30 g $KMnO_4$ as an ethylene scrubber or their mixture. In the presence of the ethylene scrubber, losses in mineral contents of alcohol insoluble solids and water soluble pectin were remarkably suppressed, whereas no significant difference was observed in the Ca content between the fresh fruit and those stored for 10 days. Fruits packaged with the ethylene absorbent retained higher amount of pectic substances than those with other packaging treatments. Degradation of the pectic substances into small molecules was also noticeably reduced when the ethylene scrubber was used. Overall results showed that the combination of the gas permeable film and the ethylene absorbent could be applied to mature-green Mume fruits as an effective packaging method to retard the texture softening during storage at the ambient temperature.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.10
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• pp.386-392
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• 2020

The self-weight of the 3D printing concrete increases with increasing printing height. Therefore, the lower layer must be hardened within a suitable time to secure continuous printing performance. In particular, the hardening speed of concrete is slow in the winter season when the temperature was low. Hence, the early strength of 3D printing concrete requires improvement. In domestic and international literature, cases of increasing the early strength of concrete using inorganic chemical additives, such as amine-based, nitrate-based, sodium-based, and calcium-based, have been reported. In this study, early strength improvement-type additive samples (amine-based, nitrate-based, sodium-based) were prepared, and their performance was evaluated. When using a nitrate-based additive, the early strength was increased significantly in a 10 ℃ environment. In addition, it was possible to secure a higher early strength than the existing 3D printing concrete mixed at 20 ℃.

• Journal of the Mineralogical Society of Korea
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• v.27 no.4
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• pp.251-262
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• 2014

Inorganic binders were studied in order to apply a conservation material for stone monument. A pure inorganic binder and 3 species of inorganic binder which contain additives on the basis of a pure inorganic binder were selected as test samples. Through the application of inorganic binders on Geochang granite investigate their influences on stone. pH 4.0 and 5.6 acid solution, respectively were manufactured on the basis of the acidity of domestic rainfall. Alkaline water with pH 8.0 and deionized water with pH 6.85 were prepared as control group. Changes in weights of inorganic binders were not definite according to the acidity of water while weight losses in inorganic binder type were greater after reaction with the water. The compressive strengths of pure inorganic binder was largest before the test but its decrease rate were larger after reaction with the water. Water absorption rate of inorganic binders are 6.72 to $12.44kg/m^2{\cdot}t^{1/2}$ after reaction with the water. Such high absorption was considered that it forced water to move deep into inorganic binder and made the components of inorganic binder dissolve. Acidities of the water of pH 4.0, 5.6, 6.85 and 8.0, respectively were changed to pH 9.0-10.0 after reaction with the inorganic binders. Ion concentrations in the water changed after reaction with the inorganic binders and $Mg^{2+}$, and $K^+$ significantly increased, dissolved from the binder. The high concentration of ions detected showed that the binder reacted with water and formed white salts with high solubility such as $MgSO_4{\cdot}nH_2O$, $KNO_3$. Ion concentrations significantly decreased from the binder after treatment with consolidant and water repellent.

• The Korean Journal of Food And Nutrition
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• v.20 no.1
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• pp.40-46
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• 2007

A qualitative investigation Dongchunghacho, Jelly combined with sericultural products prepared from assorted increments(0.5, 1, 1.5 and 2%) of P. japonica powder was performed. The qualitative parameters used to assess P. japonica powder increments included, hysicochemical, textural and sensory properties. The moisture and crude protein content of the Dongchunghacho Jelly were significantly greater than the control(p<0.05). Conversely, Dongchunghacho Jelly showed a propensity towards lower crude fat content than the control group. A positive trend was observed for both mineral content and dark color with increased P. japonica powder. In contrast, texture, hardness, gumminess and chewiness of the Dongchunghacho Jelly decreased with increasing levels of P. japonica powder. Color, taste, texture and overall preference of Dongchunghacho Jelly were optimal in the 1 % P. japonica powder mixture.

• Journal of Life Science
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• v.29 no.9
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• pp.996-1001
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• 2019

Edible insects are reported to be rich in protein, minerals and vitamins, and much attention has been paid to them as a future food source. In Korea, they were massively reared and sold. In order to enhance the market value of edible insects for industrialized mass production, it is important to develop the safe and nutritious feed sources for rearing them are needed. In this study, a chlorella-free control feed (Exp1) and six experimental feeds supplemented with 0.5~2.0% liquid or powder types of chlorella were formulated. Protaetia brevitarsis and Allomyrina dichotoma, registered as food ingredients in Korea, were fed with the designed feeds and parameters of growth including larval survivorship, larval body weight, and larval period were analyzed. When chlorella added, larval survivorship was increased 2~13%(p>0.05) and 9~22%(p<0.05) in each beetle compared to the control. Interestingly, the larval period of chlorella powder-added groups was shortened by 24 days (Exp3, p<0.05) in P. brevitarsis and 19 days (Exp4, p<0.01) in A. dichotoma. Meanwhile, some parameters, crude protein, crude fiber, copper, zinc, potassium, magnesium, and phosphorous, in chlorella-added groups of P. brevitarsis were also higher than the control group. Therefore, chlorella could promote the larval growth performance of these two beetles and be used as a feed additive in rearing them.