• 전기화학회지
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• 제3권2호
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• pp.109-114
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• 2000

다결정 $Ir/H_2SO_4$수성 전해질 계면에서 중간주파수 구간의 위상이동 변화와 Langmuir흡착등온식 사이의 관계를 교류임피던스 방법 즉 위상이동 방법을 이용하여 연구 조사하였다. 간소화된 계면 등가회로는 전해질저항(Rs), Faraday저항$(R_F)$, 흡착유사용량$(C_\phi)$ 등가회로 요소$(C_P)$의 직렬접속으로 구성된다. 음전위(E)에 대한 위상이동$(-\phi)$과 표면피복율$(\theta)$ 변화율$[\Delta(-\phi)/{\Delta}E,\;{\Delta}{\theta}/{\Delta}E]$을 비교 및 제시하였다. 지연되는 위상이동$(-\phi)$은 음전위(E) 및 주파수(f)에 따르며, $\phi=tan^{-1}[1/2{\pi}f(R_s+R_F)C_P]$이다. 중간주파수(1 Hz)에서 위상이동 변화$(-\phi\;vs.\;E)$는 Langmuir흡착등온식 $(\theta\;vs.\;E)$의 결정에 적용할 수 있는 실험적인 방법이다. 다결정 Ir/0.1 M $H_2SO_4$ 전해질 계면에서 수소의 흡착평형상수(K)와 흡착표준자유에너지 $({\Delta}G_{ads})$는 각각 $2.0\times10^{-4}$와 21.1kJ/mol이며 과전위 수소흡착(OPD H)에 기인한다.

• 한국식품영양과학회지
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• 제35권2호
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• pp.212-218
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• 2006

독화된 진주담치 (blue mussel, Mylilus edulis)를 pH 처리, 온도별 저장 그리고 가열에 의한 마비성 패류독의 독성과 독조성 특성 변화는 다음과 같다. pH 3으로 조절한 시료가 14.1 MU/g$(100\%)$으로 가장 높은 독성이 검출되었고, pH 5는 12.9 MU/g$(92.1\%)$, pH 7은 9.0 MU/g$(63.8\%)$으로 검출되었으나, 마비성 패류독은 독성이 불안정한 알칼리 조건인 pH 9에서는 3.6 Mu/g$(25.5\%)$, pH 10은 0.8 Mu/g$(5.7\%)$으로 독성 이 검출되었다. 저장기간 동안의 독성은 pH(3, 5, 7, 9) 그리고 온도(30, -5, $20^{\circ}C$)에서 5일$(19.9\~65.3\%)$까지 현저하게 감소하였으나, 5일 후부터 30일까지는 약간의 독성이 감소하였다. 그리고 더 높은 온도에서 저장에서는 독성이 더 빨리 감소하였다. 대부분의 성분인 C군(C1, C2)과 GTX1,2,3,4, STX 그리고 dcSTX으로 8개의 성분이 검출되었고, 8개의 독성분 중에서 GTX1,4, STX 그리고 dcSTX는 모든 가공 조건에서 독성이 감소함에 따라 제일 먼저 감소하였다. 독성이 기준 독성치(4 MU/g)보다 3배 이상이더라도 마쇄된 패류 육에 pH를 알칼리 (pH 7이상)로 처리하고, 10분의 가열에 의해 독성을 완전히 제거할 수 있었다.

• 한국식품조리과학회지
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• 제22권2호
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• pp.105-110
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• 2006

This study was performed to determine the sensory evaluation and mechanical characteristics of lemon red ginseng-pyun. Lemon red ginseng-pyun was made with lemon juice(21.4%), sweet potato starch(6.7%), water(53.3%), sugar(13.3%), honey(5.3%) and various concentrations of red ginseng powder(0, 2, 4, 6, 8, 10%). The quality characteristics of the sample were estimated in terms of pH, color difference, texture profile analysis and sensory evaluation. The pH of lemon red ginseng-pyun showed no significant difference among the different ratios of red ginseng. With increasing red ginseng powder addition, the lightness was significantly(p<0.05) lower, and a value and b values were significantly(p<0.05) higher. In sensory evaluation, with increasing red ginseng powder addition, the color and bitter taste of lemon red ginseng-pyun were stronger, while clarity of the 10% added red ginseng was significantly(p<0.05) lower than that of the 0% added red ginseng. Elasticity, hardness, chewiness, softness. sweet taste and overall acceptability were not significantly different in any group. In texture profile analysis, chewiness, cohesiveness, gumminess and hardness were significantly(p<0.05) increased in the 10% added red ginseng but springiness was not significantly different in any group. Overall acceptability was related to texture, appearance, overall taste and sweet taste of lemon red ginseng-pyun. Therefore, development of lemon red ginseng-pyun with no sugar or artificial sweeteners is encouraged as a healthy diet for diabetes and hypertension patients, because red ginseng is defined as a functional foods.

• Asian-Australasian Journal of Animal Sciences
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• 제29권5호
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• pp.702-708
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• 2016

Aloe vera has been used worldwide for pharmaceutical, food, and cosmetic industries due to its wide biological activities. However, quality improvement of low fat meat products and their acceptability with added Aloe vera gel (AVG) is scanty. The aim of this study was to explore the feasibility of using fresh AVG on physicochemical, textural, sensory and nutritive qualities of goat meat nuggets. The products were prepared with 0%, 2.5%, and 5% fresh AVG replacing goat meat and were analyzed for proximate composition, physicochemical and textural properties, fatty acid profile and sensory parameters. Changes in lipid oxidation and microbial growth of nuggets were also evaluated over 9 days of refrigerated storage. The results showed that AVG significantly (p<0.05) decreased the pH value and protein content of meat emulsion and nuggets. Product yield was affected at 5% level of gel. Addition of AVG in the formulation significantly affected the values of texture profile analysis. The AVG reduced the lipid oxidation and microbial growth in nuggets during storage. Sensory panelists preferred nuggets with 2.5% AVG over nuggets with 5% AVG. Therefore, AVG up to 2.5% level could be used for quality improvement in goat meat nuggets without affecting its sensorial, textural and nutritive values.

• Journal of Dental Anesthesia and Pain Medicine
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• 제22권5호
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• pp.357-367
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• 2022

Background: Low-dose dexmedetomidine may be a suitable alternative to opioids for pediatric ambulatory procedures under general anesthesia (GA). However, the recovery profile remains unclear. Herein, we aimed to evaluate the effects of low-dose dexmedetomidine on the recovery profile of children. Methods: Seventy-two children undergoing ambulatory oral rehabilitation under GA were randomly and equally distributed into two groups (D and F). Group D received an infusion of dexmedetomidine 0.25 ㎍/kg for 4 min for induction, followed by maintenance of 0.4 ㎍/kg/h. Group F received an infusion of fentanyl 1 ㎍/kg over 4 min for induction, followed by maintenance at 1 ㎍/kg/h. The primary outcome was the extubation time. The secondary outcomes were awakening time, end-tidal sevoflurane (ET-Sevo) requirement, change in hemodynamic parameters, Richmond Agitation-Sedation Scale (RASS), Children's Hospital of Eastern Ontario pain scale (CHEOPS) score, length of PACU stay, and incidence of adverse events. Results: Statistically significant differences were observed in the recovery profile between the groups: the median time for extubation was 3.65 (3.44-6.2) vs. 6.25 (4.21-7) minutes in groups D vs. F (P=0.001), respectively, while the corresponding awakening times were 19 (18.75-21) and 22.5 (22-24) minutes, respectively (P < 0.001). The mean ET-Sevo was low in group D (1.1 vs. 1.2; P < 0.001). The heart rate was significantly low across all time points in group D, without resulting in bradycardia. The median RASS and CHEOPS scores were also significantly lower in group D. No significant differences were observed in the mean arterial pressure, incidence of adverse events, or length of PACU stay. Conclusion: Low-dose dexmedetomidine was more effective than fentanyl as an opioid substitute at providing a better recovery profile in pediatric ambulatory oral rehabilitation under GA. Dexmedetomidine also significantly reduced sevoflurane consumption without causing adverse events or prolonging hospital stay.

• 한국식품영양과학회지
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• 제41권4호
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• pp.533-538
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• 2012

가래떡의 노화 특성을 분석하기 위하여 갈락토올리고당(50%)과 말토올리고당을 쌀가루 기준으로 각각 10% 농도로 첨가하여 쌀가루의 pasting 특성을 측정하였고, 가래떡을 제조하여 $5^{\circ}C$ 냉장 보관하면서 0, 2, 6, 24 및 30시간 경과 후 텍스처의 변화를 Texture Analyzer에 의해 측정하여 실험군의 떡을 무첨가군 떡과 비교하였다. 그리고 가래떡의 노화도는 텍스처 특성 중에서 0, 2, 4, 6, 22, 24, 28 및 30시간 경과 후 경도의 변화를 이용하여 Avrami 방정식에 따라 실험군의 떡을 무첨가군 떡과 비교하였다. 갈락토올리고당(50%)과 말토올리고당을 첨가한 실험군의 pasting 특성에서 peak(P) viscosity는 무첨가군에 비해 낮게 나타났고, hot paste viscosity(H)는 높게 나타났다. Breakdown(P-H)과 consistency(C-H)는 모든 실험군에서 무첨가군에 비해 낮게 나타나 올리고당을 10%를 첨가한 실험군에서 노화억제 효과가 있는 것으로 나타났다. 텍스처 특성 중 경도의 경우 실험군은 무첨가군에 비해 감소하는 경향으로 노화를 억제하는 효과를 보여 주었다. Avrami 방정식에 따른 노화 특성 분석 결과는 Avrami($n$)지수 값은 무첨가군보다 약간 높은 범위였으나 노화의 속도를 나타내는 시간상수(1/$k$)는 무첨가군 떡의 경우 43.29이었고 실험군의 경우는 82.64에서 84.75 범위로 무첨가군에 비해 그 값이 높았으며 노화속도가 느린 것으로 나타났다. 따라서 무첨가군에 비교하여 실험군 모두 경도가 낮고 노화 진행속도가 느린 것으로 나타나 갈락토올리고당(50%)과 말토올리고당을 가래떡 제조 시 10% 수준으로 첨가하면 노화억제 효과가 있는 것으로 확인되었다.

• Bulletin of the Korean Chemical Society
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• 제34권12호
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• pp.3690-3694
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• 2013

The $H_2Ge=Ge:$ and its derivatives ($X_2Ge=Ge:$, X = H, Me, F, Cl, Br, Ph, Ar${\ldots}{\ldots}$) is a new species. Its cycloaddition reactions is a new area for the study of germylene chemistry. The mechanism of the cycloaddition reaction between singlet state Cl2Ge=Ge: and formaldehyde has been investigated with CCSD(T)//MP2/$6-31G^*$ method. From the potential energy profile, it could be predicted that the reaction has only one dominant reaction pathway. The reaction rule presented is that the two reactants first form a fourmembered Ge-heterocyclic ring germylene through the [2+2] cycloaddition reaction. Because of the 4p unoccupied orbital of Ge: atom in the four-membered Ge-heterocyclic ring germylene and the ${\pi}$ orbital of formaldehyde forming a ${\pi}{\rightarrow}p$ donor-acceptor bond, the four-membered Ge-heterocyclic ring germylene further combines with formaldehyde to form an intermediate. Because the Ge: atom in intermediate hybridizes to an $sp^3$ hybrid orbital after transition state, then, intermediate isomerizes to a spiro-Ge-heterocyclic ring compound via a transition state. The research result indicates the laws of cycloaddition reaction between $H_2Ge=Ge:$ and formaldehyde, and laid the theory foundation of the cycloaddition reaction between $H_2Ge=Ge:$ and its derivatives ($X_2Ge=Ge:$, X = H, Me, F, Cl, Br, Ph, Ar${\ldots}{\ldots}$) and asymmetric ${\pi}$-bonded compounds, which is significant for the synthesis of small-ring and spiro-Ge-heterocyclic compounds. The study extends research area and enriches the research content of germylene chemistry.

• 한국환경보건학회지
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• 제33권5호
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• pp.451-455
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• 2007

This study was performed to evaluate the effects of input ratios of bulking material in aerobic composting of food wastes on variation of colony forming units(CFU) of fungi. Wood chips were used as a bulking material. Volume ratios of food wastes to wood chips in reactor of Control, WC-1 and WC-2 were 10/0, 10/5 and 10/10, respectively. Reactors were operated for 24 days with I hour stirring by 1rpm and 2 hours of the forced aeration rate of $80L/min{\cdot}m^3$ per day. WC-2 reached high temperature range faster than WC-1, and the maximum temperature of WC-2 was higher than that of WC-1. WC-2 reached high pH range faster than WC-1. and the maximum pH of WC-2 was higher than that of WC-1. WC-2 reached high Log(CFU/gram) range faster than WC-I, and the maximum Log(CFU/gram) of WC-2 was higher than that of WC-1. These all mean that the reaction velocity of composting of WC-2 was faster than that of WC-1. The profile of fungi changes in Log(CFU/gram) was similar to that of temperature changes (r=0.8861) not pH changes (r=0.1631).

• 한국가축번식학회지
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• 제17권2호
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• pp.165-171
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• 1993

Ornithine decarboxylase(ODC)가 polyamine 생합성에 주요 효소로 역할을 하지만 difluoromethylornithine(DFMO)은 polyamine 합성에 억제자로 작용하고 있다. Cycling crossbed gilt들을 무작위로 두 그룹으로 분배하였다(6/group). Indwelling silicone catheter를 모든 동물의 경정맥에 수술을 통해 이식하였다. DFMO는 생리식염수(20mg/ml)에 용해하여 매일 80mg/kg을 i.m.으로 주사하였으며 대조구에게는 같은 양의 생지식염수만을 주사하였다. DFMO는 estrous cycle day 16일부터 21일 혹은 발정때까지 하루 3번(08:00, 16:00, 24:00h) 주사하였다. Day 14일 부터 마지막 DFMO주사 이틀 후까지 하루 한번씩 10ml의 혈액을 채취하였다. Day 16일부터 21일까지 매일 다른 gilt로부터 8시간 동안(08:00∼16:00h) 15분 간격의 주기로 window 혈액을 채취하였다. Serum으로부터 progesteron(P4), Estradiol(E2), LH 및 FSH를 측정하였다. P4와 E2는 DFMO처리에 관계없이 follicular phase동안에 전형적인 profile을 보였다. DFMO처리는 발정직전의 LH농도를 저하시켰지만 (p<0.01), FSH에는 아무런 영향을 미치지 않았다. 결론적으로 gilt에 있어서 DFMO는 LH분비에 억제적인 영향을 미치는 한편, P4, E2 및 FSH에는 별로 영향을 미치지 않음이 나타났다.

• 한국수산과학회지
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• 제53권4호
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• pp.588-596
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• 2020

The seaweed Hizikia fusiformis is rich in protein, carbohydrates, vitamins, and minerals. We investigated the physicochemical properties and antioxidant activities of yanggaeng made with agar, sugar, honey, oligosaccharide, cooked white bean paste, and different amounts (0, 1, 2, 3, 4, and 5%) of H. fusiformis powder. The proximate composition, pH, sugar content, color, texture, antioxidant activity, and sensory properties of the yanggaeng were investigated. The moisture and sugar contents of the yanggaeng did not change despite increasing the amount of H. fusiformis. The pH decreased with increasing H. fusiformis. The lightness decreased significantly, whereas the redness and yellowness increased with increasing amounts of H. fusiformis. In the texture profile analysis, the hardness, gumminess, and chewiness decreased with increasing H. fusiformis content. The antioxidant activity of the yanggaeng increased with the concentration of the H. fusiformis powder. The yanggaeng containing 2% H. fusiformis had the highest overall sensory acceptance score. The addition of H. fusiformis to yanggaeng appears to improve its quality and antioxidant activity.