• Title/Summary/Keyword: and physicochemical properties

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Basic Research to Develop PGM-free DeNOx Catalyst for LNT (LNT용 PGM-free DeNOx 촉매 개발을 위한 기초연구)

  • Jang, Kil Nam;Han, Kwang Seon;Hong, Ji Sook;You, Young-Woo;Hwang, Taek Sung
    • Clean Technology
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    • v.21 no.2
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    • pp.117-123
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    • 2015
  • This inquiry was conducted to develop DeNOx catalyst for LNT. In order to develop appropriate catalysts, four catalysts, which do not use PGM (Platinum Group Metal), were carefully selected : Al/Co/Mn, Al/Co/Ni/Mn, Al/Co/Mn/Ca, Al/Co/Ni mixed metal oxides during preliminary experiments. Also, XRD, EDS, SEM, BET and TPD tests were carried as well to evaluate both physicochemical properties of such four catalysts. As a result of the experiment, four catalysts were composed of spinel-shaped crystals and had more than enough pore volume and size to have oxidation-reduction reaction of NOx gases. Additionally, through TPD test, all four types of catalysts were proved to possibly have an oxidation-reduction acid site and NO oxidation activities similar to commercial catalysts. Based on the results above, if we have further change in the composition components and active ingredients according to the catalysts that were chosen in this investigation, then we are more welcomed to expect to have an enhanced DeNox catalyst for LNT.

Optimum Milling Degree for Improving Sensory Quality of Cooked Rice (식미 증진을 위한 최적 도정도 구명)

  • Lee, Jeom-Sig;Park, No-Bong;Lee, Jong-Hee;Cho, Jun-Hyeon;Won, Yong-Jae;Park, Hyang-Mee;Chun, A-Reum;Jang, Jae-Ki;Gwak, Do-Yeon;Song, Yu-Cheon;Hwa, Woon-Gu;Yi, Gi-Hwan;Yeo, Un-Sang
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.57 no.4
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    • pp.359-364
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    • 2012
  • We conducted this study to identify the optimal milling degree for improving sensory quality of cooked rice and minimizing yield loss. The samples were analyzed for their physicochemical properties and sensory qualities using five different degree of milling(5.5~13.5%, based on brown rice). With increasing of milling degree, amylose content, breakdown, adhesiveness of cooked rice increased, whereas protein content, Mg/K equivalence ratio, fat content, setback and hardness of cooked rice decreased. In sensory quality test, the preference was significantly higher in the 9.5% and 11.5% milling degree. However, considering the yield of milled rice, the optimal milling degree for improving sensory quality of cooked rice was 9.5%.

Investigation of Changes in Grain Quality and Physicochemical Properties of Rice According to the Temperature during the Ripening Stage and Preharvest Sprouting (벼 등숙기 기온 및 수발아가 종실 품질 및 이화학적 특성에 미치는 영향)

  • Lee, HyeonSeok;Lee, YunHo;Hwang, WoonHa;Jeong, JaeHyeok;Yang, SeoYeong;Lee, ChungGen;Choi, MyoungGoo
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.65 no.4
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    • pp.294-302
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    • 2020
  • Studies on the occurrence of rice preharvest sprouting (PHS) have primarily focused on temperature and rainfall duration at the time of PHS induction, but average temperature during grain filling can have a great influence on PHS. This study analyzed the effect of average temperature during grain filling on PHS occurrence and subsequent changes in grain quality after PHS. For two consecutive years, average temperature differences during grain filling were produced by varying the transplanting date. Artificial rainfall was treated under identical accumulated temperatures of 1200℃ after heading. It was confirmed that the occurrence of PHS was higher under high average temperature conditions during grain filling. In addition, the degree of grain quality reduction caused by PHS occurred more severely under high temperature conditions during grain filling. In order to reduce the risk of PHS occurrence and subsequent quality damage, it is important to control the planting date to avoid high-temperature conditions during grain filling.

Cognitive Ability Enhancement Effects in Rats by B. mori Fibroin Enzymatic Hydrolysate (견 피브로인 효소 가수분해물의 동물 인지기능 향상 효과)

  • Yeo Joo-Hong;Lee Kwang-Gill;Kweon HaeYong;Woo Soon-Ok;Han Sang-Mi;Lee Yong-Woo;Kim Jin-Il;Kim Sung-Su;Demura Makoto
    • Journal of Sericultural and Entomological Science
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    • v.46 no.1
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    • pp.23-27
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    • 2004
  • We were investigated the cognitive ability enhancement in rats using B. mori fibroin molecular controlled hydrolysate by preparative recycle HPLC system. Also, some of its physicochemical properties and free amino acid components were investigated, too. Nuclear magnetic resonance (NMR) spectrum are measured different pattern between high (HF) and low (LF) molecular controlled B. mori fibroin samples, respectively. The in vitro test by neuron primary cell culture are showed dependent on molecular weight (Mw) of B. mori fibroin in the order of LF > MF > HF, too. However, the memorial effects in rats by in vivo test are large dependent molecular weight on that maximum 50% than control. Also, the memorial effect was higher than the enzymatic relative and acid hydrolysate, which was 50.0$\pm$2.1 and 25.9$\pm$0.32%, respectively.

Quality Characteristics of Low-Fat Sausage Containing Curcumin Extract during Cold Storage (울금 추출물 함유 저지방 소시지의 냉장저장 중 품질 특성)

  • Kim, Il-Suk;Jin, Sang-Keun;Park, Ki-Hoon;Jeong, Ki-Jong;Kim, Dong-Hoon;Yang, Mi-Ra;Chung, Young-Sin
    • Food Science of Animal Resources
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    • v.27 no.3
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    • pp.255-261
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    • 2007
  • The effects of curcumin extract on the physicochemical, microbial and sensory properties of low-fat sausages during refrigerated storage were studied. Sausage products were produced with three different formulations including 0%, 2.5%, and 5.0% curcumin extract. Low-fat sausages made with the addition of curcumin extract had lower (p<0.05) crude fat content, pH and TBARS values than the control sample. The addition of curcumin extract did not affect the water holding capacity, cooking loss, shear force, meat color, texture profile, and total bacterial count in low-fat sausages duringstorage (p>0.05). With regard to sensory evaluation, 2.5% curcumin extract added to low-fat sausages resulted in a high overall acceptability (p<0.05). In conclusion, low-fat sausages with added 2.5% curcumin extract had a higher acceptability and lipid oxidative stability during storage than products without curcumin extract.

Batch Scale Storage of Garlic by Irradiation Combined with Natural Low Temperature (방사선(放射線) 조사(照射)와 자연저온(自然低溫)에 의한 마늘의 저장)

  • Cho, Han-Ok;Kwon, Joong-Ho;Byun, Myung-Woo;Yoon, Hyung-Sik
    • Korean Journal of Food Science and Technology
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    • v.16 no.1
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    • pp.66-70
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    • 1984
  • An attempt was made on the development of a commercial scale storage method of garlic by irradiation. Irradiated garlics with 50, 100 and 150 Gy were stored at natural low temperature storage room $(12{\pm}6^{\circ}C,{\;}75-85%{\;}RH)$ and the physicochemical properties during the 10 months storage were investigated. The unirradiated garlic was mostly sprouted after 8 months storage, whereas the sprouting of all irradiated groups was completely inhibited until 10 months storage, The rotting rate and weigh loss of garlic after 10 months storage were reduced by 25 to 54% at 100 Gy irradiation compared with those of an unirradiated group. The moisture content remained relatively constant during the whole storage period. The total sugar content was increased with storage period. Ascorbic acid content was also decreased until 8 months storage but its content was rapidly increased along with sprouting. Garlic was marketable after 10 months storage by 100 Gy irradiation combined with natural low temperature.

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Leaching characteristics of the bipyridylium herbicide paraquat in soil column (토양 column 중 bipyridylium계 제초제 paraquat의 용탈 특성)

  • Kwon, Jeong-Wook;Lee, Jae-Koo
    • The Korean Journal of Pesticide Science
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    • v.3 no.2
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    • pp.29-36
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    • 1999
  • The leaching behaviour of $^{14}C$-paraquat in soil was investigated using soil columns (5 cm I.D. ${\times}$ 30 cm H.) parked with two soils of different physicochemical properties. $^{14}C$-Activities leached from the soil A (loam) columns with and without rice plants for 117 days were 0.42 and 0.54% of the originally applied, whereas those from the soil B (sandy loam) were 0.21 and 0.31%, respectively. $^{14}C$-Activities absorbed by rice plants from soil A and B were 3.87 and 2.79%, respectively, most of which remained in the root. Irrespective of soil types, more than 96% of the total $^{14}C$ resided in soil, mostly in the depth of $0{\sim}5$ cm. The water-extractable $^{14}C$ in soil was in the range of $6.10{\sim}9.01%$ of the total $^{14}C$ applied. The rest of $^{14}C$, which corresponds to non-extractable soil residues of [$^{14}C$]paraquat, was distributed in humic substances in the decreasing order of humin>humic acid>fulvic acid. The soil pH of the columns without rice plants increased after the leaching experiment due to the flooded anaerobic condition resulting in the reduction of the $H^{+}$ concentration, whereas that of the columns with rice plants did not increase by the offsetting effect of the acidic exudates from the roots. Low mobility of paraquat in soil strongly indicates that no contamination of ground water would be caused by paraquat residues in paddy soils under normal precipitation.

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Study on the Critical Micelle Concentration Changes of Surfactants in Magnetized Water (자화수에서 계면활성제 임계미셀농도 변화에 관한 연구)

  • Lee, Sung-Hyun;Lee, Suk-Keun;Jeon, Sang-Il
    • Journal of the Korean Chemical Society
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    • v.53 no.2
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    • pp.125-132
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    • 2009
  • The magnetized water is known to have a unique pattern of hydrogen bond between water molecules, thereby producing different physicochemical properties from the ordinary water. We have examined the effect of magnetized water on the change of critical micelle concentrations (CMC) of some surfactants. The CMC changes of SDS (sodium dodecyl sulfate) and CTAB (cetyltrimethylammonium bromide) dissolved in the magnetized water have been determined by the conductivity measurement at $25\;{^{\circ}C}$ and that of SDS, CTAB and Pluronic F-68 have also been examined by the surface tension method at $25\;{^{\circ}C}$. The CMC variation of SDS was examined by ITC (Isothermal Titration Calorimeter) at $25\;{^{\circ}C}$. The CMC of SDS, CTAB, and Pluronic F-68 are more decreased in the magnetized water, SDS is about $2.7{\sim}6.5$25 %, CTAB is about $2.3{\sim}3.0$%, and Pluronic F-68 is about 24.2 %, than in the control water.

Application of Rice Polishing By-products to Processed Rice Food (I) - Antioxidative Effect of Black Rice Bran Pigment Fraction on Rice Embryo Lipid Oxidation - (쌀 가공식품 제조용 소재로서의 도정 부산물 활용 방안 (I) - 흑미 미강 색소 분획의 쌀 배아 산패 억제 효과 -)

  • Cho, Min-Kyung;Kim, Sung-Hong;Kang, Mi-Young
    • Journal of the East Asian Society of Dietary Life
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    • v.18 no.3
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    • pp.361-367
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    • 2008
  • This study examined the physicochemical properties of rice embryo in order to investigate the antioxidative effect of black rice bran pigment fraction on rice embryo lipid oxidation. Color stability of rice bran pigment fraction and acid value of added rice embryo were determined at various conditions of pH, temperature, and storage time. Rice embryo contained more crude protein (22.1%) compared to the rice bran (9.4%). However, rice embryo had a higher lipid content than rice bran, causing lipid oxidation during storage. Pigment fraction were relatively stable in acidic pH of 3.0 stored at $4^{\circ}C$ for 9 days. Rice embryo showed increased acid value with increased storage time and temperature. Furthermore, rice embryo with pigment fraction resulted in lower acid value compared to the control group. Therefore, addition of black rice bran pigment fractions to rice embryo improved storage capacity.

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Physicochemical Properties of Cement Paste Containing Mg(OH)2 Cured by CO2 curing Method (CO2 양생을 이용한 Mg(OH)2 혼입 시멘트 페이스트의 물리화학적 특성)

  • Chen, Zheng-Xin;Lee, Han-Seung
    • Journal of the Korea Institute of Building Construction
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    • v.18 no.3
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    • pp.203-210
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    • 2018
  • Corrosion of the rebar is one of the main factors affecting the durability of reinforced concrete in the world which lead to the failure of the reinforced concrete structures. In this research, a new method of fixing $CO_2$ is practiced to improve the carbonation resistance of the concrete. Brucite($Mg(OH)_2$), a kind of common $CO_2$ fixation materials, was added into ordinary Portland cement paste. Samples containing 0%, 5%, 10%, and 15% $Mg(OH)_2$ were exposed to an accelerated carbonation curing regime with 20% concentration of $CO_2$, 60% relative humidity, and a temperature of $20^{\circ}C$ until tested at 3d, 7d, 14d and 28d. After 28d of $CO_2$ accelerated curing, in the paste containing $Mg(OH)_2$, magnesian calcite was detected by SEM-EDX. Meanwhile, the paste containing $Mg(OH)_2$ exhibit the better pore distribution than ordinary Portland cement paste and the compressive strength of the cement paste containing $Mg(OH)_2$ were more than 50Mpa.