• 한국축산식품학회지
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• 제40권2호
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• pp.197-208
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• 2020

The effects of presalting conditions (storage temperature and duration) with/without sodium tripolyphosphate (STPP) on the color and pigment characteristics of cooked ground chicken breast were investigated. Meat mixtures containing 2% NaCl (control) or 2% NaCl and 0.5% STPP (STPP treatment) were stored for 0, 3, 5, 7, and 10 d at 2℃ or 7℃, followed by cooking to 75℃, and cooling and storage at 2℃-3℃ until further analysis. The treatment was the most effective on the pink color defect of all independent variables. The effect of storage temperature was only observed on CIE L^⁎ values and percentage myoglobin denaturation (PMD). The control was redder than the STPP treated samples and the CIE a^⁎ values increased (p<0.05) from 0 to 5 d in the control and STPP treated samples. Compared to the STPP treatment, the control exhibited increased reducing conditions (more negative oxidation reduction potential), lower undenatured myoglobin, and greater PMD. No differences in the cooking yields of the control and STPP-treated samples were observed for various storage durations. Products with STPP showed higher (p<0.05) pH values than those without STPP, but no differences (p>0.05) in PMD were observed over the storage period in the control and STPP treated samples, except for day 0. Thus, STPP is effective at reducing the pink color in cooked chicken breasts. In addition, presalting for longer than 5 d resulted in increased pink color of the cooked chicken breasts.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1992년도 추계학술대회 논문집
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• pp.136-140
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• 1992

The purpose of this research is to develop the lithium secondary battery. This paper describes the preparation, electrochemical properties of nontstoichiometric(NS)-$V_6O_{13}$ and characteristics of Li/$V_6O_{13}$ secondary battery. NS-$V_6O_{13}$ was prepared by thermal decomposition of $NH_4VO_3$ under Ar stream of 140ml/min~180ml/min flow rate. And then, this NS-$V_6O_{13}$ was used for cathode active material. Cathode sheet was prepared by compressing the composite of NS-$V_6O_{13}$, acetylene black(A.B) and teflon emulsion (T.E). Characteristics of the test cell are summarised as follows. Oxidation capacity of NS-$V_6O_{13}$ was about 20% less than its reduction capacity. A part of NS-$V_6O_{13}$ cathode active material showed irreversible reaction in early charge-discharge cycle. This phenomena seems to be caused by irreversible incoporation/discoporation of lithium cation to/from NS-$V_6O_{13}$ host. Discharge characteristics curve of Li/$V_6O_{13}$ cell showed 4 potential plateaus. Charge-discharge capacity was declined in the beginning of cycling and slowly increased in company with increasing of coulombic efficiency. Energy density per weight of $V_6O_{13}$ cathode material was as high as 522Wh/kg~765Wh/kg.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1996년도 하계학술대회 논문집 C
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• pp.1414-1417
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• 1996

The purpose of this study Is to research and develop $V_{6}O_{13}$ composite cathode for lithium thin film battery. $V_{6}O_{13}$ represents a class of cathode active material used in Li rechargeable batteries. In this study, we investigated cyclic voltammetry and charge/discharge characteristics of $V_6O_{13}$/SPE/Li cells. Cyclic voltammogram of $V_{6}O_{13}$/SPE/Li cell at scan rate 1mV/sec showed reduction peaks of 2.25V and 2.4V and oxidation peaks of 2.4V and 2.2V. The discharge curve of $V_{6}O_{13}$/SPE/Li cell showed 4 potential plateaus. The discharge capacity was decreased in the beginning of charge/discharge cycling. After 8th cycling, the discharge capacity was stable. The discharge capacity of 1st cycle and 15th cycle was 290mAh/g and 147mAh/g at $25^{\circ}C$, respectively.

• 한국재료학회지
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• 제11권4호
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• pp.251-257
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• 2001

반도체 소자의 고집적화에 따른 세정공정 수는 점점 증가하고 있는 추세에 있다 현재 사용되는 세정은 다량의 화학약품 및 초순수를 소비하며, 고온에서 행하여지고 있는 RCA세정을 근간으로 하고 있다. 세정공정수의 증가는 바로 화학약품의 사용량 증가를 초래하게 되며, 이에 따른 환경문제가 심각하게 대두되고 있는 실정에 이르렀다. 따라서 이러한 화학약품 및 초순수 사용을 절감하고, 저온에서 세정공정이 이뤄지는 기술이 향후 요구되어 지고 있다. 이번 연구는 이러한 관점에서 화학약품 및 초순수 사용량을 줄이며, 상온 공정이 이뤄지는 전리수를 이용하여 실리콘 웨이퍼 세정을 하였다. 제조된 전리수는 산화성 성질을 지닌 양극수와 환원성 성질인 음극수로 이루어지고, 각각 pH 및 ORP는 4.7/+1050mV, 9.8/-750mV를 30분 이상 유지하고 있었다 전리수의 양극수에 의한 금속제거 효과가 음극수의 효과보다 우수함을 확인할 수 있었으며, 다양한 입자제거 실험에도 불구하고, 동일한 분포도를 나타내고 있었다.

• Journal of Microbiology and Biotechnology
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• 제20권11호
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• pp.1577-1584
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• 2010

In total, 140 halotolerant bacterial strains were isolated from both the soil of barren fields and the rhizosphere of six naturally growing halophytic plants in the vicinity of the Yellow Sea, near the city of Incheon in the Republic of Korea. All of these strains were characterized for multiple plant growth promoting traits, such as the production of indole acetic acid (IAA), nitrogen fixation, phosphorus (P) and zinc (Zn) solubilization, thiosulfate ($S_2O_3$) oxidation, the production of ammonia ($NH_3$), and the production of extracellular hydrolytic enzymes such as protease, chitinase, pectinase, cellulase, and lipase under in vitro conditions. From the original 140 strains tested, on the basis of the latter tests for plant growth promotional activity, 36 were selected for further examination. These 36 halotolerant bacterial strains were then tested for 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase activity. Twenty-five of these were found to be positive, and to be exhibiting significantly varying levels of activity. 16S rRNA gene sequencing analyses of the 36 halotolerant strains showed that they belong to 10 different bacterial genera: Bacillus, Brevibacterium, Planococcus, Zhihengliuella, Halomonas, Exiguobacterium, Oceanimonas, Corynebacterium, Arthrobacter, and Micrococcus. Inoculation of the 14 halotolerant bacterial strains to ameliorate salt stress (150 mM NaCl) in canola plants produced an increase in root length of between 5.2% and 47.8%, and dry weight of between 16.2% and 43%, in comparison with the uninoculated positive controls. In particular, three of the bacteria, Brevibacterium epidermidis RS15, Micrococcus yunnanensis RS222, and Bacillus aryabhattai RS341, all showed more than 40% increase in root elongation and dry weight when compared with uninoculated salt-stressed canola seedlings. These results indicate that certain halotolerant bacteria, isolated from coastal soils, have a real potential to enhance plant growth under saline stress, through the reduction of ethylene production via ACC deaminase activity.

• 한국물환경학회지
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• 제22권2호
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• pp.203-208
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• 2006

A continuous feed and cyclic draw SBR process was developed to overcome flow rate fluctuation and to maximize organic matters utilization efficiency for nitrogen and phosphorus removal. The developed SBR process was operated with two parallel reactors. Influent was supplied to one reactor which was not obligately aerated. At the same time, the other reactor was just aerated without supplying influent. In addition this mode was changed periodically. Cycle time was 6hr and aeration time ratio($t_{aer}/t_{total}$) was 0.33, respectively. $COD_{cr}$ and SS removal efficiencies of 95% or higher were achieved. Nitrogen removal was so greatly influenced by influent $COD_{cr}/T-N$ ratio. At influent $COD_{cr}/T-N$ ratio of 5.7, removal efficiencies of ammonia-N, T-N and T-P were 96%, 78% and 55%, respectively. Influent $COD_{cr}/T-N$ of 4 or higher ratio was necessary to achieve 60% or higher nitrogen removal. Organic matters of influent was efficiently utilized in denitrification reaction and consumed COD has a good correlation with removed T-N(about 6.5 mgCOD/mgTN). Continuous feed and cyclic draw SBR process could be one of alternative processes for the removal of nutrients in rural area where $COD_{cr}/T-N$ ratio was low and fluctuation of flow rate was severe.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
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• pp.562-562
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• 2012

Recently, graphene and graphene-based materials such as graphene oxide (GO) or reduced graphene oxide (R-GO) draws a great attention for electronic devices due to their structures of one atomic layer of carbon hexagon that have excellent mechanical, electrical, thermal, optical properties and very high specific surface area that can be high potential for chemical functionalization. R-GO is a promising candidate because it can be prepared with low-cost from solution process by chemical oxidation and exfoliation using strong acids and oxidants to produce graphene oxide (GO) and its subsequent reduction. R-GO has been used as semiconductor or conductor materials as well as sensing layer for bio-molecules or ions. In this work, reduced graphene oxide field-effect transistor (R-GO FET) has been fabricated with ITO extended gate structure that has sensing area on ITO extended gate part. R-GO FET device was encapsulated by tetratetracontane (TTC) layer using thermal evaporation. A thermal annealing process was carried out at $140^{\circ}C$ for 4 hours in the same thermal vacuum chamber to remove defects in R-GO film before deposition of TTC at $50^{\circ}C$ with thickness of 200 nm. As a result of this process, R-GO FET device has a very high stability and durability for months to serve as a transducer for sensing applications.

• 지질공학
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• 제18권3호
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• pp.297-302
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• 2008

폐광산 인근의 토양과 광미에서 발생하는 오염원은 중금속과 강산성의 배수가 주요한 원인물질이다. 이러한 오염원들은 인근의 토양까지 오염이 확산되어 결국 사람에게 건강상 유해성을 나타낸다. 본 연구에서는 중금속 오염이 심각한 폐광산을 대상으로 이들의 관리를 최적화하기 위해 요구되는 중금속 오염수준예측을 위한 수학적 접근방법을 시도하였다. 이를 위해 폐광산으로부터의 거리와, pH 및 산화환원전위(ORP)의 경시변화를 조사하여 이들의 상관성을 방정식으로 도출하였다. 대상으로 한 폐광산에 따라 다소의 차이는 보였으나, 60일간의 실험기간동안 변화되는 pH와 ORP는 초기의 pH와 ORP를 기준으로 할 때, 변화율이 $0.95{\sim}1.03$의 범위로 나타났다. 이것은 초기의 pH와 ORP를 기초로 폐광산 인근의 토양에서 발생하는 중금속류의 용출정도를 예측하여 환경영향평가를 실시할 수 있음을 시사하며, 이러한 접근방법은 다른 폐광산에도 적용할 수 있으므로 제거 또는 제어 대상인 중금속류의 관리에 유용하게 사용될 것으로 기대한다.

• 한국식품과학회지
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• 제35권1호
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• pp.62-66
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• 2003

해조류와 소금물을 이용하여 해조소금을 제조하고 이화학적 특성과 무기성분을 비교하였다. 해조소금 제조에 사용한 해조류의 회분함량은 미역이 22.78%로 많았고 김이 9.81%로 적었으나 무기성분으로 미역은 Na함량이 많은 반면 다시마와 톳은 K와 Ca가 많았다. 건조만 한 소금을 회화시켜 물불용해성분을 제거하면 소금의 순도가 증가하여 색이 밝아졌으며 pH와 ORP가 저하하였고, K와 Ca함량은 증가하나 Mg가 감소하였다. 해조소금의 수율은 미역소금에서 높았고 ORP는 다시마와 톳소금에서 낮았으며, K와 Ca함량은 미역소금에 비하여 다시마와 톳소금이 현저히 많았다. 해조소금 제조시 소금물의 농도가 증가하면 소금의 수율과 순도는 증가하나 pH는 저하하였고, ORP와 Ca, Mg함량이 증가하였다. 해조소금을 SEM에 의해 표면관찰 한 바 소금의 외형이 작고 특징적인 결정구조를 보였다.

• Journal of Applied Biological Chemistry
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• 제56권1호
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• pp.11-17
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• 2013

부원료 첨가를 달리하여 제조한 쌈장을 포장하여 $30^{\circ}C$에서 18주간 저장하면서 저장중 이화학적인 특성 변화를 검토하였다. 쌈장의 색은 L-와 a-, b-값 모두 저장중 서서히 감소하였으며, ${\Delta}E$값의 변화는 대조구에서 심하였다. 쌈장 저장중의 가스 생성은 K-sorbate와 알코올, 겨자 첨가로 억제되었다. 저장중 쌈장의 효모수는 6주에 급격히 증가하였으나 겨자와 알코올, K-sorbate 첨가구에서 적었고, 매실즙과 울금 첨가구에서 많아 이들 첨가구에서 효모수의 증가가 가스 생성의 직접적인 원인이 되었다. 산화환원전위(ORP)는 저장 6주, 수분활성도는 저장 12주까지 저하되었으나 그 이후에는 근소한 증가를 보였다. 적정산도는 저장 중에 pH의 저하에 따라 증가되었으며, K-sorbate와 알코올 첨가구에서 적었다. 환원당은 울금 첨가구를 제외하고는 저장 9주까지 증가되었으며, 알코올은 매실즙과 울금 첨가구는 저장 15주까지 증가되었다. 쌈장은 유의적인 차이는 없으나 맛과 향기에서 겨자와 울금 첨가구가 양호하였고 전체적인 기호도에서 겨자 첨가구가 양호한 것으로 판단되었다.