• 대한수의학회지
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• 제25권2호
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• pp.133-144
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• 1985

The changes of acid-base status in vitro of the venous blood for 24 hours in ten Korean native goat were investigated. The acid-base parameters were measured within ten minutes after collection of the blood, and every hour during the first six hours and finally after twenty four hours of storage. Blood samples were stored at two different temperatures ($0-4^{\circ}C$ and $21-24^{\circ}C$). Twelve goats were induced acute acid-base disturbances by intravenous infusion of either hydrochloric acid or sodium bicarbonate and inhalated with $CO_2$ gas mixture (20% $CO_2$, 80% $O_2$) or hyperventilation were performed by means of respirator. The results were as follows; 1. Blood samples could be stored during the first two hours in ice water ($0-4^{\circ}C$) and one hour at room temperature without significant changes in pH. The magnitudes of changes were similar to those of cow, and lower than those of men and dogs. 2. The mean values of acid-base parameters in normal goat were arterial pH, 7.40; $P_{CO_2}$, 35.4mmHg; $HCO_3{^-}$, 21.8mEq/L. 3. Both the base excess and the bicarbonate showed high correlation (r=0.99) during the metabolic disturbance and were represented as $B.E.=1.38\;HCO^-{_3}-29.7$. 4. The slope of blood buffer curve obtained from the in vivo experiment was 16.3mEq/L/pH. 5. The magnitudes of changes in hydrogen ion concentration per unit change of $P_{CO_2}$ were 0.8nM/mmHg in hypercapnia and 1.0nM/mmHg in hypocapnia. 6. The ranges of acid-base parameters in normal goat urine were pH, 6.0-8.1; $P_{CO_2}$, 42-61mmHg; $HCO_3{^-}$, 2-110mEq/L. The concentration of potassium was higher (60-200mEq/L), and that of sodium was lower (8-70mEq/L) than those of human urine.

• 한국세라믹학회지
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• 제37권5호
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• pp.511-515
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• 2000

The effect of Ba2+ ion dissolution with different pH and amount of PAA on microstructural changes of green and sintered bodies and its electrical properties was studied in aqueous nano-size BaTiO3 slurry system. The dissolution of Ba2+ was least at strong base, pH 10.8 and by addition of amount of 0.15 wt% PAA. The green body with the lowest of dissolution of Ba2+ at pH 10.8 and 0.15 wt% PAA had minimum values of average pore size, 40nm and shown high increase of sintered density. The compact sintered at 125$0^{\circ}C$ for 2 hr with highest Ba2+ dissolution had low density and dielectric constant due to abnormal grian growth. However, the sintered body with the lowest Ba2+ dissolution had high sintered density and then shown high dielectric constant.

• 한국식품과학회지
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• 제45권5호
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• pp.590-597
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• 2013

고전압 펄스 전기장 기술은 가열 공정을 대체할 수 있는 비가열 살균기술로서 꾸준한 연구가 이루어지고 있는 기술이다. 본 실험에서는 미생물의 생리적 측면에서 고전압 펄스 전기장 처리에 의한 효모의 생리적 변화를 살펴보았다. 내염성의 변화를 측정한 결과 사멸하지 않은 세포의 90-99% 이상이 세포 손상에 의해 내염성을 소실하였으며, 내염성을 회복하는데 약 4-6시간의 시간이 걸렸다. 고전압 펄스 전기장 처리 초기에는 세포 내외의 pH 구배(${\Delta}pH$)가 차이가 컸으나 처리시간이 증가함에 따라 그 차이가 감소하였다. 이는 세포의 pH 항상성을 유지시키는 $H^+$-traslocation 기능을 담당하고 있는 $H^+$-ATPase 활성이 소실되었거나 세포막 자체가 손상되어 pH 항상성을 잃어버렸기 때문으로, 이는 고전압 펄스 전기장 처리한 세포의 $H^+$-ATPase의 활성이 초기부터 크게 감소하는 것으로 확인할 수 있었다. 또한 세포의 해당활성이 고전압 펄스 전기장 처리에 의해 크게 감소하여 세포의 대사 기능이 손상되는 것을 확인하였다.

• 한국의류산업학회지
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• 제3권1호
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• pp.31-34
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• 2001

The color difference values of dyed fabrics with colorant in Eucommiae Cortex were as follows; One hour of dyeing depending on pH at $95^{\circ}C$ exhibited colors of dark brown, light brown, light beige and grey. The colors of wool, nylon and silk was darkest brown at pH 3 but light brown or yellow as pH increased. In all dyed fabrics the color was changed to darker brown as time prolonged, however; there was no further color change and value and chroma of wool declined. At pH 3, the increase in temperature turned colors of all dyed fabrics into dark brown from light yellow. As the result of repetitive dyeing, colors of all dyed fabrics gradually turned into darker brown. The methods of mordant resulted in color changes between light yellow and dark brown without various color changes.

• 한국식품과학회지
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• 제20권4호
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• pp.476-482
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• 1988

김치의 발효 과정중 김치의 주요 품질의 변화를 알기 위하여 김치액의 pH와 총산도, 부피와 고형분의 양 그리고 색을 측정하였으며, 김치의 맛, 냄새, 텍스쳐에 대한 관능적 성질을 평가하였다. 김치의 발효는 배추를 소금물에 절인뒤 $4-35^{\circ}C$ 범위의 온도에서 발효시켰다. 그 결과 pH의 감소나 총산도의 증가는 변화 속도에 따라 초기, 중간, 최종 단계의 3단계로 구분할수 있었으며, 이들의 변화는 sigmoidal곡선을 보여 주었다. pH와 총산도가 가장 빠르게 변화하는 중간 발효 단계에서의 계산된 활성에너지는 각각 15.67 및 18.99Kcal/mole이었다. 발효중 배추 조직으로부터 나온 김치액은 발효초기에 빠르게 증가하다가 완만하여 졌으며 김치액의 총 고형분은 초기에 증가하였다가 감소하는 현상을 보였다. Hunter L값은 약간씩 증가하였고 김치액의 색은 연한녹청색으로 변화하였다. 김치의 관능적 성질은 pH 4.0부근에 도달할 때까지 상큼한 맛과 냄새 및 사각사각한 조직감이 증가하다가 발효 최종 단계에서 모두 감소하였으며 군덕내와 맛은 급격히 증가하였다.

• 한국미생물·생명공학회지
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• 제26권3호
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• pp.221-225
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• 1998

Y-CB와 Y-UCB를 음용하였을 때, 장내 비피더스균수, 유산간균수, 대장균수 및 분변의 pH, 수분함량(%) 등 장내환경 변화에 어떤 영향을 미치는지 검토하였다. 시험 대상자는 20～30세의 건강한 성인 남녀 14명으로 하였으며 평상시의 분변 상태를 조사한 다음 요구르트를 하루 2병씩 식후에 음용하도록 하였다. 음용시험의 방법은 Y-CB와 Y-UCB를 2주간 1차 음용 시험후 2주간의 음용 중단 기간을 가졌으며, 다음 제2차 음용시험으로서는 1차 음용시의 공시요구르트를 교차음용 하면서 분변상태를 비교 분석하였다. Y-UCB의 음용중에는 음용전과 비교하여 비피더스균수(p<0.01)와 유산간균수(p<0.05)는 유의성있게 증가하였고, 수분, pH, 대장균수에는 변화가 없었다. Y-CB의 음용은 음용전과 비교하여 비피더스균수는 증가하였고(p<0.01), 대장균수는 감소하였으며(p<0.05), 유산간균수, 수분, pH는 변화가 없었다. 두 개의 공시 요구르트를 음용 전과 비교하면 음용중단 후에도 비피더스균수가 증가하였고, 낮은 pH를 지속하였으며, 유산간균수, 수분, 대장균수의 변화는 없는 것으로 나타났다 결과적으로 유산균발효유의 음용효과(비피더스균수, 유산간균수, 대장균수, pH, 수분함량의 변화측정 ) 비교에 있어서 본 실험에 사용한 Y-CB나 Y-UCB는 어느 것이나 거의 동등한 효과를 나타내었으며 통계적으로 유의 차가 없는 것으로 나타났다(p>0.05).

• The Korean Journal of Ecology
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• 제20권4호
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• pp.275-283
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• 1997

Vertical and temporal characteristics of desalinized reclaimed soil were analyzed from reclaimed coastal land on the western coast of Korea. Of the vertical changes during desalting, pH valuse were the lowest at the topsoil without regard to reclaimation time. The content of C1 were designated as the early period (the first 2-4 years) which decreased exponentially and the later period(the last 5-7 years) which was almost constant, from top to down. In temporal changes of the soil attributes, pH values increased for 5 years and decreased at 6 year after reclamation. Chlorine leaches more rapidly than Na does, K and Ca are constant but Mg increases as time elapsed after reclamation. Sometimes the content of Ca and K in the reclaimed soil are of higher concentration than that of the seawater after reclamation. During desallinization as exemplified by decreasing EC of the soil, Cl and Na are rapidly leached, but K, Ca and Mg are somewhat enhanced. The ration of Na/Cl in the soil equals 1 when the EC registers 5 mmho and then increases dramatically as the EC decreases. Rapid leaching of $Cl^{-}$ elicits an increasing pH valus. The electrostatic balance of the soil is achived by replacement of $Cl^{-}$ with $OH^{-}$ until stationary or until a decreasing pH value is reached again.

• 환경생물
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• 제17권2호
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• pp.209-215
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• 1999

온도, pH및 염도 stress가 굴(Crassostrea gigas)의 malate dehydrogenase isozyme에 미치는 영향을 전기영동법으로 분석하였다. 대조군의 MDH isozyme은 2개의 band가 양극 쪽으로 이동되어 분리되었다. 각 실험 온도와 pH를 12시간 노출시킨 실험군에서는 1개의 band만 양극 쪽에서 분리되었고, 24시간과 48시간 노출한 실험군에서는 2개의 band가 모두 양극 쪽에서 분리되었다. 염분 농도가 5ppt 와 3ppt에서 12시간 노출시켰을 때 각각 2개의 band가, 10ppt와 40ppt에서는 각각 3개의 band가 분리되었고, 24시간과 48시간 노출 실험군에서는 2개의 band가 양극 쪽에서 분리되었다. 모든 isozyme pattern에서 각 band의 활성도는 실험 조건에 따라 각각의 특이성이 나타났다. 결과적으로 MDH isozyme의 변화는 굴이 환경 stress에 대한 생화학적 반응의 결과로 간주된다.

• 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).

• Archives of Pharmacal Research
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• 제23권4호
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• pp.360-366
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• 2000

The in vivo binding of dopamine (DA) radioligands to $D_2$receptors can be affected by competition with endogenous dopamine. In the present study, we used a brain slice preparation that provides more controlled conditions than in vivo preparations in order to examine the relationship between synaptic DA and the binding of [$^3H$] raclopride to $D_2$receptors. We also estimated the synaptic DA concentration in rat striatal slices by determining the changes in [$^3H$] raclopride binding. To correlate the changes in [$^3$H]raclopride binding with the concentration of synaptic DA, the kinetic parameters were determined. [$^3H$] Raclopride reached equilibrium binding conditions within two hours. The K value for DA in inhibiting [$^3$H]raclopride binding was about 2.2 nM. The increase in synaptic DA evoked by electrical stimulation decreased the striatal binding of [$^3H$] raclopride in a frequency-dependent manner. Increases in the DA concentration evoked by amphetamine (AMPH) or cocaine decreased [$^3H$] raclopride binding by 74% or 20%, respectively, corresponding to increases in the synaptic DA concentrations of 1.6 nM or 0.6 nM, respectively. Pargyline also decreased [$^3H$] raclopride binding by 36%corresponding at a concentration of 1.2 nM. In contrast, the depletion of synaptic DA by $\alpha$-methyl-p-tyrosine ($\alpha$-MpT) increased the specific binding of [$^3H$] raclopride by 43%when the DA concentration was decreased to 0.7 nM. The changes in the DA concentration at the synapse were responsible for the changes in the striatal binding of [$^3H$] raclopride. The values calculated in this study may therefore approximate the changes in the synaptic DA concentration in rat striatal slices following manipulation.