• 공업화학
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• 제5권4호
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• pp.657-661
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• 1994

FTIR을 이용하여 암모니움 카바메이트와 요소의 혼합액은 물론, 각각의 농도를 분석하는 방법을 연구하였다. 본 연구에서는 15% w/v암모니아 용액을 용매로 이용하여 암모니움 카바메이트 수용액에서 발생하는 ammonium bicarbonate의 생성을 억제하였으며, 평형위치에 대한 오차를 1% 미만으로 유지하였다. $1600cm^{-1}$에서의 N-H bending에 의한 요소 흡수 피크와 $1405cm^{-1}$에서의 symmetric carboxylate ion stretch에 의한 암모니움 카바메이트 흡수 피크를 이용하여 보정 그래프를 그린 후 농도 계산식을 만들었다. 농도 측정간에 대한 오차는 암모니움 카바메이트에 대하여 ${\pm}0.1%$ w/v이었으며, 요소에 대하여 ${\pm}0.3%$ w/v이었다.

• 상하수도학회지
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• 제18권2호
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• pp.174-180
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• 2004

This study is a fundamental research to test the applicability of abandoned eggshell as seed material for crystallization reaction. Eggshell was calcinated at $850^{\circ}C$ and ground to lesser than 0.42mm. The calcination characteristics of eggshell were examined by X-ray diffraction (XRD). The effect of initial calcium concentration, alkalinity, reaction temperature condition, seed dosage were studied by batch test. For the low concentration sample(P concentration is under 50mg/L), more than 90% of P can be removed. The effect of initial calcium concentration(0~120mg/L) was performed. At the result of the test, more than 50mg/L calcium concentration has high removal efficiency. Alkalinity effect was studied for synthetic solution(100mg/L initial P, 50mg/L calcium, 0.025% seed dosage) with 0~300mg/L bicarbonate alkalinities. For synthetic solution(100mg/L initial P, 50mg/L calcium, 100mg/L bicarbonate alkalinity, 0.025% seed dosage), the phosphorus concentration was examined with $10{\sim}35^{\circ}C$. In addition, calcinated eggshell was injected to swine wastewater to test the applicability to actual wastewater.

• 약학회지
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• 제32권1호
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• pp.26-39
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• 1988

Eudragit $RS^{\circledR}$ polymer was used as a wall material for the microencapsulation of aspirin by a phase separation method from chloroform-cyclohexane system with 5% polyisobutylene (PIB) in cyclohexane, and microcapsules obtained were evaluated by particle size analysis, scanning electron microscopy (SEM), drug release and drug stability test. With PIB as a coacervation inducing agent, smooth and tight microcapsules with less aggregation were obtained. Below 1 : 0.3 core-wall ratio, it was possible to coat individual particle. Variation of production conditions showed that increasing the proportion of wall material, particle size and wall thickness of microcapsules and the concentration of paraffin wax in cyclohexane as a sealant sustained drug release rates effectively. SEM confirmed that larger microcapsules after drug release did not rupture into smaller particles but contained a few small pores on the surface. Aspirin release from Eudragit $RS^{\circledR}$ coated microcapsules was independent of the pH of medium, and the mechanism of drug release from non-sealed and sealed microcapsules appeared to fit Higuchi matrix model kinetics. Aspirin in the mixture of aspirin microcapsules and sodium bicarbonate was by far more stable than that in the mixture of pure aspirin and sodium bicarbonate.

• Journal of Microbiology and Biotechnology
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• 제22권7호
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• pp.967-974
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• 2012

Cultivation of Spirulina platensis using ammonium salts or wastewater containing ammonium as alternative nitrogen sources is considered as a commercial way to reduce the production cost. In this research, by analyzing the relationship between biomass production and ammonium-N consumption in the fed-batch culture of Spirulina platensis using ammonium bicarbonate as a nitrogen nutrient source, an online adaptive control strategy based on optical density (OD) measurements for controlling ammonium feeding was presented. The ammonium concentration was successfully controlled between the cell growth inhibitory and limiting concentrations using this OD-based feedback feeding method. As a result, the maximum biomass concentration (2.98 g/l), productivity (0.237 g/l d), nitrogen-to-cell conversion factor (7.32 gX/gN), and contents of protein (64.1%) and chlorophyll (13.4mg/g) obtained by using the OD-based feedback feeding method were higher than those using the constant and variable feeding methods. The OD-based feedback feeding method could be recognized as an applicable way to control ammonium feeding and a benefit for Spirulina platensis cultivations.

• 한국동물위생학회지
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• 제25권3호
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• pp.299-308
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• 2002

The purposes of this study were to characterize the disposition of sulfathiazole(ST) and to investigate the effects of sodium bicarbonate on the disposition of ST in broiler chicks(2.5～3.0kg). Animals were given ST acutely(10～80mg/kg, PO), and plasma, kidney, muscle, heart, liver and spleen samples were collected and analyzed for ST by high performance liquid chromatography. The plasma and tissue data was consistent with a one-compartment pharmacokinetic model. The drug is rapidly but incompletely(2.5～3.87%) absorbed with peak plasma and tissue levels being achieved within one hour after dosing. The plasma and tissue levels depended on drug dosage, and the descending order in concentration of ST was kidney > plasma > heart > muscle $\geq$ spleen $\geq$ liver from animals sacrificed at one hour after dosing. Moreover, significant positive correlations(r>0.9) existed between plasma and tissue levels of ST. In addition, sodium bicarbonate pretreatment decreased plasma level, indicating that an alkalinization stimulate the excretion of ST. Results of this study suggest that oral application of ST was rapidly absorbed and eliminated, and confirmed that tissue residues of ST can be estimated from plasma drug concentration in broiler chicks.

• 근관절건강학회지
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• 제28권1호
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• pp.41-49
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• 2021

Purpose: This study aimed to compare the effects of the Difflam spray 0.3% with the sodium bicarbonate-normal saline spray on oral care for postoperative patients. Methods: The participants were randomly allocated to either the Difflam (n=22) group or the saline solution (n=23) group. The data were collected at the 1-, 4-, 7-, and 10-hour marks after returning to the ward post operation using the Beck's subjective oral discomfort scale, Visual Analogue Scale for sore throat, and portable halitosis detector. Results: The sore throat (F=7.25, p=.001) score significantly decreased after oral care using the Difflam spray 0.3%. However, the difference in the scores of oral comfort (F=0.34, p=.797) and halitosis (F=0.91, p=.443) between the two groups was not statistically significant. Conclusion: These findings suggest that the Difflam spray 0.3% is effective in improving postoperative sore throat. A further study that explores the effect of various oral solutions for postoperative patients is needed to present systemic and effective evidence-based oral care guidelines.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제27권2호
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• pp.88-94
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• 2024

Purpose: Infantile hypertrophic pyloric stenosis (IHPS) is a common gastrointestinal disease in neonates and hypochloremia metabolic alkalosis is a typical laboratory finding in affected patients. This study aimed to analyze the clinical characteristics of infants with IHPS and evaluate the association of clinical and laboratory parameters with ultrasonographic findings. Methods: Infants diagnosed with IHPS between January 2017 and July 2022 were retrospectively evaluated. Results: A total of 67 patients were included in the study. The mean age at diagnosis was 40.5±19.59 days, and the mean symptom duration was 11.97±9.91 days. The mean pyloric muscle thickness and pyloric canal length were 4.87±1.05 mm and 19.6±3.46 mm, respectively. Hyponatremia and metabolic alkalosis were observed in five (7.5%) and 36 (53.7%) patients, respectively. Serum sodium (p=0.011), potassium (p=0.023), and chloride levels (p=0.015) were significantly lower in patients with high bicarbonate levels (≥30 mmol/L). Furthermore, pyloric canal length was significantly higher in patients with high bicarbonate levels (p=0.015). To assess metabolic alkalosis in IHPS patients, the area under the receiver operating characteristic curve of pyloric canal length was 0.910 and the optimal cutoff value of the pyloric canal length was 23.5 mm. Conclusion: We found a close association between laboratory and ultrasonographic findings of IHPS. Clinicians should give special consideration to patients with pyloric lengths exceeding 23.5 mm and appropriate fluid rehydration should be given to these patients.

• Journal of Chest Surgery
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• 제11권4호
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• pp.404-415
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• 1978

The present study was carried out to develop the better measures for safety of open heart surgery under extracorporeal circulation (ECC) with Heart-Lung-Machine by preventing changes in the concentrations of serum electrolytes during and after ECC. For this purpose, the cocentrations of serum electrolytes were measured before, during, and after ECC in 21 patients with congenital and acquired heart diseases who received open heart surger, - under ECC using Heart-Lung-Machine. Also considered was the development of safety measured by which changes in serum electrolyte concentrations were prevented during and after open heart surgery under ECC. The mean values for serum sodium levels were observed to be ; $13.14{\pm}0.47$mEq./L. for the samples obtained before ECC. $139.59{\pm}0.68$mEq./L. for the samples obtained 10 minutes after ECC and $138.0{\pm}0.68$mEq./L. for the samples obt"ined 24 hours after ECC. These results indicate that serum sodium concentrations were \\'ithin normal range during and until 24 hours after ECC. 2) The concentrations of serum chloride were found to be $105.38{\pm}0.70$105.38$\pm$0. 70 mEq./L. for the samples collected before ECC, $105.07{\pm}1.01$mEq./L. for the Simples collected 24 minutes aiter ECC and $101.95{\pm}1.09$mEq./L. for the samples collectect 24 hours afte ECC. As was tile case with serum sodium levels, no significant changes were observed in serum chloride levels during and 24 hours after ECC. 3)With proper provisions of potassium chloride solution during ECC, the concentrations of serum potassium were found to be $4.22{\pm}0.06$mEq./L. for the samples removed before EeC, $4.06{\pm}0.14$mEq./L. for the samples removed 10 minutes after ECC and $4.39{\pm}0.07$ mEq./L. for the samples removed 24 hours after ECC. 4)The concentrations of serum calcium were also maintained within normal during and after ECC; $9.15{\pm}0.14$mg/dl for the serum collected before ECC, $8.36{\pm}0.21$mg/dI for the serum collected 10 minutes after ECC and $8.47{\pm}0.14$mg/dl 21 hours after ECC. The maintenance of serum calcium level within normal throughout ECC was achieved by parenteral administrations of calcium gluconate as frequent as required. 5) As were the cases with serum potassium and calcium, the concentrations of plasma bicarbonate was regulated within normal range during and after ECC, only when sodium bicarbonate solution was admini"tered parenterally as it was required; $23.7{\pm}0.50$mEq./L. for the serum collected before ECC. $22.33{\pm}1.09$mEq.lL. for the serum collected 10 minutes after ECC and $25.3{\pm}0.96$mEq./L. for the serum collected 24 hours after ECC. The above results indicate tha t during and after ECC serum sodium and chloride levels remined unchanged without any provision of normal saline, while serum potassium, calcium, and bicarbonate concentrations were kept within normal limits only when these ealectrolytes were administered through parenteral routes. With these results it can be concluded that serum potassium, calcium, and bicarbonate levels should be determined as often as possible during and after ECC and that in order to maintain serum electrolyte levels within normal these electrolytes in the forms of potassium chloride, calcium gluconate, and sodium bicarbonate shou'd be given parenterally as they were found to be required.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제30권1호
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• pp.22-29
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• 2008

Purpose: The purpose of this study is to test the efficacy of various methods of fat harvesting in animal model by viability comparison with assay including cell counting, MTT assay, and histologic evaluation. Materials and methods: New Zealand white rabbits experiments were used. Groin fat pads were subjected to different harvest method varying ingredients of solution(Experiment 1: T1 solution= lidocaine 1000mg/L, epinephrine 1mg/L, sodium bicarbonate 10mgEq/L, Triamcinolone 10mgEq/L; T2 solution=lidocaine 1000mg/L, epinephrine 1mg/L, sodium bicarbonate 0mgEq/L, Triamcinolone 0mgEq/L) and pressure exerted on harvesting with Luer-Lock syringe connected to suction cannula.(Experiment 2: P1 group=3cc intermittent pressure; P2 group=10cc sustained pressure) Fat cell viability was assessed with cell counting with a hemocytometer, MTT assay, and histologic evaluation. Results: Experiment 1 Cell count: T1=2.4/3.4/4.2, T2=9.6/8.4/7.2($\times10^5$ per mL); MTT assay: T1=0.516/0.41/0.453/0.412/0.421, T2=0.925/0.765/0.54/0.634/0.614 in 21 days(absorbance); Histology: T1 showed elongated and, different in size and shape, and ruptured adipocytes with only a few normal adipocytes whereas T2 showed central core of fat with almost intact fat cells Experiment 2 Cell count: P1=1.2/3.2/4.2, P2=1.2/2.4/3.8($\times10^5$ per mL); MTT assay:P1=0.256/0.245/0.258/0.21/0.264, P2=0.12/0.231/0.245/0.313/0.281 in 21 days(absorbance); Histology: P1 showed somewhat evenly distributed normal-looking fat cells and P2 showed relatively irregular shape of fat cells with small blood vessel amongst adiopocytes. Conclusion: Viability was higher in ‘modified tumescent solution’without sodium bicarbonate and triamcinolone and we also found no significantly different viability between using intermittent pressure and using sustained pressure. But in terms of initial viability of fat cell, we can assume that lower intermittent pressure would make better clinical results.

• 자원환경지질
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• 제31권1호
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• pp.11-20
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• 1998

카올리나이트에 의한 세슘-137 및 스트론튬-90 흡착에 대한 지하수의 주요 양이온 ($Ca^{2+}$, $Mg^{2+}$, $K^+$, $Na^+$ 및 음이온 ($SO_4{^{2-}}$, $HCO_3{^-}$)의 영향을 그리고 pH의 영향을 뱃치실험을 통하여 알아보았다. 세슘 및 스트론튬 흡착에 대한 지하수 양이온들의 농도, 전하, 이온반경사이의 상대적인 영향을 알아보기 위하여 통계적 방법으로 디자인된 3차원적인 Kd 모델링 방법이 시도되었다. 모델링결과 흡착에 미치는 정도는 양이온의 수화반경이 가장 큰 영향을 미치며, 그다음 이온들의 전하, 농도의 순서임이 밝혀졌다. pH변화에 따른 카올리나이트의 제타전위를 측정하고 amphoteric 반응측면에서 Cs, Sr 흡착 특성을 설명하였다. 카올리나이트의 Cs 및 Sr 흡착에 대한 경쟁양이온들의 이온강도가 pH 보다는 더 큰 영향을 미친다. 탄산수소이온의 농도는 스트론튬의 흡착거동에 상당한 영향을 미친다. 이는 탄산수소이온 ($HCO_3{^-}$)의 농도변화에 다른 pH의 변화에 기인하는 것 뿐만아니라, WATWQ4F 프로그램을 이용한 열역학적 계산에 의하면 Strontianite ($SrCO_3$)의 침전에 의한 것으로 해석된다.