• Korean Chemical Engineering Research
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• 제51권2호
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• pp.240-244
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• 2013

정삼투식 담수화 기술은 차세대 담수 방법으로 주목을 받고 있으나, 상용화를 위해서는 유도용액 처리공정에서의 에너지 효율 향상을 필요로 한다. 중탄산암모늄을 유도용질로 이용하는 정삼투식 담수화 시스템은 정삼투 막모듈, 유도용액 분리공정, 유도용액 회수공정으로 이루어진다. 담수 생산을 위한 유도용액 분리공정에서 발생하는 암모니아와 이산화탄소의 혼합기체는 연속운전 및 경제성 향상을 위하여 회수되어 중탄산암모늄 용액으로 재농축되어야 한다. 이러한 유도용액 회수공정의 흡수액으로 희석된 중탄산암모늄 용액을 이용하는 방법이 있다. 본 연구에서는 용액의 농도에 따른 흡수성능 및 특성을 관찰하기 위한 실험을 수행하였고, 정삼투식 담수 공정에서 중탄산암모늄 용액을 분리된 암모니아와 이산화탄소 재농축에 이용할 수 있음을 확인하였다. 본 연구의 결과는 파일럿급 정삼투식 담수 공정의 설계 및 운전에 활용될 예정이다.

• Asian-Australasian Journal of Animal Sciences
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• 제21권12호
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• pp.1728-1735
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• 2008

The present study was conducted with four ruminally canulated Holstein cows to observe the effects of monensin or fish oil on diet fermentation and production of conjugated linoleic acids (CLAs) in the rumen when fed diets supplemented with soybean oil and sodium bicarbonate. Cows of the control treatment were fed a basal diet (CON) consisting of 60% commercial concentrate and 40% chopped rye grass hay. Cows of other treatments were fed the same diet as CON, but the concentrate was supplemented with 7% of soybean oil and 0.5% of sodium bicarbonate (SO-B), SO-B supplemented with monensin (30 ppm, SO-BM) or concentrate supplemented with 6.3% of soybean oil, 0.5% of sodium-bicarbonate, 30 ppm of monensin and 0.7% of fish oil (SO-BMF). Dry matter (DM) intake of the cows was significantly (p<0.011) reduced by feeding the SO-BMF diet compared to the other diets which did not differ in DM intake. Whole tract digestibility of major dietary components was significantly (p<0.004-0.027) higher for SO-BMF than the other supplement-containing diets. Dietary supplements did not clearly affect rumen pH and ammonia concentrations compared to the CON diet. Significantly reduced (p<0.05) total VFA concentration was obtained by the addition of fish oil to the diet (SO-BMF) compared to other diets. No differences, however, were obtained in major VFA proportions as well as in total VFA between the supplemented diets. The SO-BM diet increased (p<0.01-0.05) the concentrations of trans-11 $C_{18:1}$ and linoleic acid in rumen fluid. Total CLA concentration was also increased by the feeding of SO-B and SO-BM diets during early fermentation times (up to 3 h) post-feeding. Cis-9, trans-11 CLA concentration in rumen fluid was highest (p<0.05) for SO-B up to 1 h while the highest (p<0.01) value for SO-BM occurred at 3 h post-feeding. An increased trans-10, cis-12 CLA concentration was obtained from the SO-B and SO-BM diets at 1 and 3 h post feeding compared to the other diets. Supplementation of oils with monensin and sodium bicarbonate increased (p<0.05) the proportions of $C_{18:1}$ and CLA in the plasma of cows, but the effect of monensin and/or fish oil was limited to trans-10, cis-12 CLA.

• Applied Microscopy
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• 제22권2호
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• pp.84-96
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• 1992

Turtle bladder 상피세포(上皮細胞)의 수송기작(輸送機作)을 in vitro에서 효과적으로 연구하기 위하여 Lucite chamber 한가운데 상피조직을 두고 전압고정법(電壓固定法)을 적용하여 상피 세포층의 막전위(膜電位)를 측정한 후 급속 동결(凍結)하고 투과 및 주사형 전자현미경(電子顯微鏡)으로 탄산 탈수효소를 함유하는 세포의 표면막 특성을 분석(分析)하였다. 방광(膀胱)의 점막층(粘膜層)은 두 타입의 탄산탈수효소를 함유한 세포가 특징적인데 정단부(丁端部)와 기저부(基底部) 세포막에서는 각기 다른 수송의 특성을 나타내고 있다. 즉 ${\alpha}$ 및 ${\beta}$형 탄산탈수효소가 풍부한 세포는 정단세포막(丁端細胞膜)의 proton 펌프를 이용하여 $H^+$ 분필(分泌)에 관여하거나 bicarbonate의 재흡수(再吸收) 기능을 가지는 것으로 믿어진다. 본 연구에서 탄산탈수효소를 함유한 ${\alpha}$형의 세포의 proton 분필수송(分泌輸送)과 세포막 투과성 변화와의 상관관계를 관찰하였는 바, 이들 세포에서 $H^+$을 분비하는 과정에서 정단부의 표면세포막(表面細胞膜) P-face에는 특이한 구조로서 세포막내(細胞膜內) 입자(粒子)들이 다량으로 분포하였다. 이와같은 세포막내(細胞膜內) 입자(粒子)들은 proton 펌프를 함유하는 것으로 생각되며 ${\beta}$형의 세포에서는 기저세포막(基底細胞膜)에서 관찰되고 있다. 이와같은 결과는 방광상피(膀胱上皮) 세포내 탄산탈수효소는 $H^+$과 $HCO_{3}^{-}$의 생성에 관여하지만, 특히 ${\alpha}$형 세포에서 정단세포막의 proton 펌프를 이용한 $H^{+}$ 분필수송(分泌輸送)과 기저세포막을 통한 bicarbonate의 재흡수(再吸收) 기능을 설명해 주는 중요한 사실로서 사료된다.

• 생태와환경
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• 제43권4호
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• pp.471-476
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• 2010

Monthly up-river discharge in the riverine zone analysis resulted in large interannual variations and differences in calcium ($Ca^{2+}$), bicarbonate ($HCO_3^-$), and cations in the lacustrine zone (Lz) of Daecheong Reservoir during the wet year (Wy, 1993) vs. dry year (Dy, 1994). Total up-river discharge in the Wy was four times that of the Dy, and the up-river discharge in July~August of the Wy was eight times greater than that of same period of Dy. Annual water retention time in the Lz showed large difference between the two years. Water residence time (WRT) was minimum when the up-river discharge peaked, whereas the WRT was maximum when the up-river discharge was at minimal condition. This peak discharge from the up-river on early July reduced residence time in the Lz on mid-July~late July. Monthly pattern, based on data of May~November, was similar between the two years, but, but mean retention time in the Wy was 50 days shorter than in the Dy. Such hydrology, up-river discharge, and WRT reduced $Ca^{2+}$, $HCO_3^-$, and cations in the Lz. At low up-river discharge in Wy during April~May, the cation content of Ca+Mg+Na+K averaged 1.17meq $L^{-1}$ (range=1.09-1.26meq $L^{-1}$), but as the up-river discharge increased suddenly, the values decreased. Seasonal fluctuations of $Ca^{2+}$ showed exactly same pattern with bicarbonate ion of $HCO_3^-$. The minimum $Ca^{2+}$ (0.03meq $L^{-1}$) was occurred in the early August of wet year and coincided with the minimum $HCO_3^-$. These results suggest that the magnitude of variation in $Ca^{2+}$, bicarbonate, and cations in the lacustrine zone is directly determined by the peak magnitude of up-river discharge. The magnitude of up-river discharge determined water retention time and the magnitude of ionic dilution in the lacustrine zone, resulting in functional changes of the ecosystem.

• 한국약용작물학회지
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• 제28권6호
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• pp.421-427
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• 2020

Morus alba, Anti-obesity, C57BL/6 Mice, Expression, Flavonoid, Gene, Mulberry Background: The seed oil of Zanthoxylum schinifolium S. et Z. (sancho) is a traditional cooking oil that has long been sold at a very high price however, depending on the method of extraction and storage, this oil becomes rancid occurs very quickly. Therefore, this study aimed to find a material that prevents rancidity and improves the storage properties of sancho oil. Methods and Results: Sancho oil was extracted using an extraction press, and acid values were compared with commercially available vegetable oils, sancho oil had a higher acid value than other vegetable oils. A very high acid value was observed in sancho oil stored for 6 months, regardless of temperature, requiring an effective storage method. The high acid value and the decrease in turbidity of sancho oil are dependent on the days of sedimentation. Treatment with sodium bicarbonate by concentration resulted in minimal changes in acid value over time. However, minor differences were detected among the treatment concentrations. Ascorbic acid was added to maximize the effect of sodium bicarbonate, and it was observed that ascorbic acid did not improve the antioxidant effect. The sodium bicarbonate and ascorbic acid mixture resulted in minimal change in acid value at temperature up to 25℃. Conclusions: Sancho oil becomes rancid very quicky and requires efficient storage techniques. Sodium bicarbonate and ascorbic acid have been proven to be useful as safe anti-racidity agents without causing harm to humans.

• Childhood Kidney Diseases
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• 제13권2호
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• pp.235-241
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• 2009

목적 : 소아기의 급성 위장염은 소화장관액의 수분, 전해질 및 산-염기물질의 체외 상실로 인하여 산-염기 대사의 장애를 초래한다. 중탄산염차이(bicarbonate gap, 이하 BG)는 델타음이온차이(delta anion gap, 이하 ${\Delta}AG$)와 델타중탄산염차이(delta bicarbonate, 이하 ${\Delta}HCO_3{^-}$) 의 차이로 정의되며 혼합 산-염기 대사의 장애의 정도를 평가하는데 유용한 지표가 된다. 본 연구에서는 BG에 따른 임상 양상을 비교하였다. 방법 : 2007년 9월 1일부터 2008년 4월 31일까지 구로 고려대학교 의료원에 급성 위장염으로 입원한 135명을 대상으로 후향적으로 의무기록은 검토하였다. 대상 환아들을 BG이 -5 미만이거나 5 초과인 A군과 -5 이상이고 5 이하인 B군으로 나누어 입원기간, 열, 구토, 설사 등의 임상양상과 나트륨, 칼륨, 염소, 알부민, 단백질, 혈액요서질소(blood urea nitrogen, 이하 BUN), 크레아티닌, 혈청 내 이산화탄소, 음이온차이, ${\Delta}AG$과 ${\Delta}HCO_3{^-}$ 등의 검사 결과를 비교하였다. 결과 : BG이 -5미만인 A군은 66명, BG이 -5이상인 군인 B 군은 69명이었다. 입원기간은 A군에서 $5.3{\pm}2.1$일, B 군에서 $4.7{\pm}1.6$일로 A군에서 유의하게 길었으며 입원 전 설사 기간은 A군에서 $3.13{\pm}1.7$일, B군에서 $2.3{\pm}1.7$일로 A군에서 더 길었으며 총 설시사간은 A군에서 $4.2{\pm}2.8$일, B군에서 $3.3{\pm}2.5$일로 A군에서 유의하게 길었다(P<0.05). 혈청 내 나트륨, 이산화탄소, 단백질, AG, ${\Delta}AG$은 A군이 B군에 비해 유의하게 낮은 값을 보였으며 혈청 내 염소, ${\Delta}HCO_3{^-}$는 A군이 B군에 비해 유의하게 높았다(P<0.05). 발열, 구토 기간과 칼륨, 혈액요소질소, 크레아티닌, 알부민 AG과 $HCO_3$ radio의 검사 결과는 유의한 차이가 없었다. 결론 : 본 연구에서는 급성 위장염을 보이는 환아들 중에서 BG이 -5 미만인 A군에서는 입원기간과 입원 전 설사 시간, 총 설사기간이 더 길어 임상경과가 좋지 않음을 보여주고 있으며 검사 결과 또한 혈청 내 나트륨, 총 이산화탄소, 단백질 AG, ${\Delta}AG$, 혈청 내 염소, ${\Delta}HCO_3{^-}$는 BG 범위에 따라 유의한 차이를 보이고 있어 소아기 급성 위장염에서 BG은 임상 경과의 예측 및 치료의 적절성을 평가하는데 유용한 자료로 이용될 수 있으리라 사료된다.

• The Korean Journal of Physiology and Pharmacology
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• 제6권1호
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• pp.41-46
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• 2002

Effect of cadmium (Cd) intoxication on renal acid-base regulation was studied in adult male Sprague-Dawley rats. Cd intoxication was induced by subcutaneous injections of $CdCl_2$ at a dose of 2 mg Cd/kg/day for $3{\sim}4$ weeks. In Cd-intoxicated animals, arterial pH, $PCO_2$ and plasma bicarbonate concentration decreased, showing a metabolic acidosis. Urine pH and urinary bicarbonate excretion increased and titratable acid excretion decreased with no change in ammonium excretion. In renal cortical brush-border membrane vesicles derived from Cd-exposed animals, the $Na^+/H^+$ antiporter activity was significantly attenuated. These results indicate that chronic exposures to Cd impair the proximal tubular mechanism for $H^+$ secretion (i.e., $Na^+/H^+$ antiport), leading to a metabolic acidosis.

• 동력기계공학회지
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• 제15권6호
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• pp.81-85
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• 2011

Because of excellent mechanical properties, such as good friction coefficient and heat resistance characteristics, PTFE parts have been widely used in the industries. However, the poor wear resistance of PTFE has been a main problem limiting wider applications. In this study, to improve the poor wear resistance of PTFE, porous PTFE composites were prepared by mixing additives(sodium bicarbonate and graphite) with PTFE powder. The friction coefficient, wear resistance and lubricating property of porous PTFE composites were measured and the results were compared with those of untreated PTFE.

• Childhood Kidney Diseases
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• 제14권2호
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• pp.120-131
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• 2010

Renal tubular acidosis (RTA) is a metabolic acidosis due to impaired excretion of hydrogen ion, or reabsorption of bicarbonate, or both by the kidney. These renal tubular abnormalities can occur as an inherited disease or can result from other disorders or toxins that affect the renal tubules. Disorders of bicarbonate reclamation by the proximal tubule are classified as proximal RTA, whereas disorders resulting from a primary defect in distal tubular net hydrogen secretion or from a reduced buffer trapping in the tubular lumen are called distal RTA. Hyperkalemic RTA may occur as a result of aldosterone deficiency or tubular insensitivity to its effects. The clinical classification of renal tubular acidosis has been correlated with our current physiological model of how the nephron excretes acid, and this has facilitated genetic studies that have identified mutations in several genes encoding acid and base ion transporters. Growth retardation is a consistent feature of RTA in infants. Identification and correction of acidosis are important in preventing symptoms and guide approved genetic counseling and testing.

• EDISON SW 활용 경진대회 논문집
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• 제3회(2014년)
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• pp.287-299
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• 2014

Bicarbonate anion ($HCO_3{^-}$) takes the role of major buffer systems in our body by maintaining the pH at 7.4. Epithelial $HCO_3{^-}$ secretion also hydrolyzes the mucus which protects body from noxious infections. It has been widely known that such infections are closely related to $HCO_3{^-}$ permeability through membrane and, thus, increasing the $HCO_3{^-}$ permeability is essential. To evaluate the $HCO_3{^-}$ permeability through ion channels, the free energy changes relevant to ion pumping are calculated with the Integral Equation Formalism-PCM (IEF-PCM) theory. Molecular structures of various anions including $HCO_3{^-}$ were optimized with the density functional theory at the level of B3LYP/6-311++G(d,p) in gas and solution phase. In addition, the anion permeability is significantly influenced by the relative size of the anion and pore. We introduce a shifted volume factor model that describes the pore size effect when the charged solutes transfer through ion channels. We found excellent agreement between experimental and calculated permeability when our novel model of the size effect was taken into account to.