• YAKHAK HOEJI
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• v.7 no.2_3
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• pp.67-71
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• 1963

Studies the reaction mechanism and optimal reaction condition of the process of preparing sodium isocyanate, by means of heating of sodium carbonate and urea. Proposing, at the sametime, the quantitative analyzing method of sodium isocyanate in the presence of impurities of $Na_{2}CO_{3}$, urea and biuret. 1. Sodium isocyanate could be prepared by means of heating reaction of sodium carbonate and urea. 2. Adding urea into the heated sodium carbonate is reasonable. 3. Quantitative analysis of sodium isocyanate in the presence of impurities, $Na_{2}CO_{3}$, urea and biuret could be done by the following method:-adding nitrobarite solution into sample solution in order to remove $CO_{3}"$ and neutralize the solution, filtering off $BaCO_{3}$, and then precipitating isocyanate as a silver salt, filtering off AgNCO, and then, titrating remaining $AgNO_{3}$ with $NH_{4}SCN$, (indicator $FeNH_{4}(SO_{4})_{2})$/TEX>

• Bulletin of the Korean Chemical Society
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• v.23 no.11
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• pp.1507-1508
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• 2002

• Analytical Science and Technology
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• v.37 no.2
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• pp.114-122
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• 2024

A transmission Raman spectroscopy-based quantitative model, which can analyze the content of a drug product containing naproxen sodium as its active pharmaceutical ingredient (API), was developed. Compared with the existing analytical method, i.e., high-performance liquid chromatography (HPLC), Raman spectroscopy exhibits high test efficiency owing to its shorter sample pre-treatment and measurement time. Raman spectroscopy is environmentally friendly since samples can be tested rapidly via a nondestructive method without sample preparation using solvent. Through this analysis method, rapid on-site analysis was possible and it could prevent the production of defective tablets with potency problems. The developed method was applied to the assays of the naproxen sodium of coated tablets that were manufactured in commercial scale and the content of naproxen sodium was accurately predicted by Raman spectroscopy and compared with the reference analytical method such as HPLC. The method validation of the new approach was also performed. Further, the specificity, linearity, accuracy, precision, and robustness tests were conducted, and all the results were within the criteria. The standard error of cross-validation and standard error of prediction values were determined as 0.949 % and 0.724 %, respectively.

• Bulletin of the Korean Chemical Society
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• v.28 no.10
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• pp.1635-1636
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• 2007

• Korean journal of food and cookery science
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• v.27 no.5
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• pp.497-505
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• 2011

The purpose of this study was to apply molecular gastronomy and spherification methodology to persimmon deserts. We prepared 'persimmon calcium alginate beads' and investigated their physical and sensory characteristics by adding different concentrations of sodium alginate (0.4, 0.6, 0.8, and 1.0%). Lightness and yellowness decreased significantly as the concentration of sodium alginate increased. However hardness, springiness, chewiness, cohesiveness, and resilience but not adhesiveness tended to increase as the concentration of sodium alginate increased. The thickness of the beads increased as the concentration of sodium alginate increased. In contrast, the thickness of the membrane decreased as the concentration of alginate increased from 0.8 to 1.0% suggesting that the amount of sodium alginate had reached a critical point. Quantitative descriptive analysis showed that voluminosity, springiness, hardness, chewiness, and residue tended to increase as the concentration of sodium alginate increased. Overall preference reached a peak at 0.4% sodium alginate.

• Nutrition Research and Practice
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• v.17 no.2
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• pp.175-191
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• 2023

BACKGROUND/OBJECTIVES: The scientific evidence of a sodium-obesity association is limited by sodium intake assessments. Our specific aim is to synthesize the association between dietary sodium intake and obesity across the sodium intake assessments as evidenced by systematic reviews in adults. SUBJECTS/METHODS: A systematic search identified systematic reviews comparing the association of dietary sodium intakes with obesity-related outcomes such as body mass index (BMI), body weight, waist circumference, and risk of (abdominal) obesity. We searched PubMed on October 24, 2022. To assess the Risk of Bias in Systematic Reviews (ROBIS), we employed the ROBIS tool. RESULTS: This review included 3 systematic reviews, consisting of 39 unique observational studies (35 cross-sectional studies and 4 longitudinal studies) and 15 randomized controlled trials (RCTs). We found consistently positive associations between dietary sodium intake and obesity-related outcomes in cross-sectional studies. Studies that used 24-h urine collection indicated a greater BMI for those with higher sodium intake (mean difference = 2.27 kg/m²; 95% confidence interval [CI], 1.59-2.51; P < 0.001; I² = 77%) compared to studies that used spot urine (mean difference = 1.34 kg/m²; 95% CI, 1.13-1.55; P < 0.001; I² = 95%) and dietary methods (mean difference = 0.85 kg/m²; 95% CI, 0.1-1.51; P < 0.05; I² = 95%). CONCLUSIONS: Quantitative synthesis of the systematic reviews has shown that cross-sectional associations between dietary sodium intake and obesity outcomes were substantially different across the sodium intake assessments. We need more high-quality prospective cohort studies and RCTs using 24-h urine collection to examine the causal effects of sodium intake on obesity.

• Bulletin of the Korean Chemical Society
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• v.24 no.9
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• pp.1319-1323
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• 2003

This paper presents a successful demonstration of the on-line coupling of MEKC (micellar electrokinetic chromatography) to ESIMS (electrospray ionization mass spectrometry) for the quantitative analysis of seven s-triazine herbicides. The on-line MEKC-ESIMS was used to determine the structure of CE-separated peaks of seven triazine herbicides. The mixture of triazine herbicides was separated in a 20 mM sodium borate buffer (pH 8.5) containing 15 mM sodium dodecylsulfate (SDS) by using a bare fused-silica capillary. Electrospray ionization mass spectrometer was operated in the positive-ion mode when the mass spectra of seven triazine herbicides were observed from each peak, and the solution of water-methanol-formic acid (50/49/1 v/v/v) was used as a sheath liquid. The effects of SDS concentration, the run buffer pH, and the electric field on the separation of seven s-triazine herbicides were investigated. The MEKC-ESIMS detection showed 5 to 10 times higher sensitivity compared to the MEKC-UV detection. In addition, it did not need any pretreatment step.

• Nutrition Research and Practice
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• v.14 no.1
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• pp.32-44
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• 2020

BACKGROUND/OBJECTIVE: We have previously designed the anti-cancer food scoring model (ACFS) 1.0, an evidence-based quantitative tool analyzing the anti-cancer or carcinogenic potential of diets. Analysis was performed using simple quantitative indexes divided into 6 categories (S, A, B, C, D, and E). In this study, we applied this scoring model to wider recipes and evaluated its nutritional relevance. MATERIALS/METHODS: National or known regional databases were searched for recipes from 6 categories: Korean out-dining, Korean home-dining, Western, Chinese, Mediterranean, and vegetarian. These recipes were scored using the ACFS formula and the nutrition profiles were analyzed. RESULTS: Eighty-eight international recipes were analyzed. All S-graded recipes were from vegetarian or Mediterranean categories. The median code values of each category were B (Korean home-dining), C (Korean out-dining), B (Chinese), A (Mediterranean), S (vegetarian), and D (Western). The following profiles were correlated (P < 0.05) with ACFS grades in the univariate trend analysis: total calories, total fat, animal fat, animal protein, total protein, vitamin D, riboflavin, niacin, vitamin B₁₂, pantothenic acid, sodium, animal iron, zinc, selenium, and cholesterol (negative trends), and carbohydrate rate, fiber, water-soluble fiber, vitamin K, vitamin C, and plant calcium (positive trends). Multivariate analysis revealed that animal fat, animal iron, and niacin (negative trends) and animal protein, fiber, and vitamin C (positive trends) were statistically significant. Pantothenic acid and sodium showed non-significant negative trends (P < 0.1), and vitamin B₁₂ showed a non-significant positive trend. CONCLUSION: This study provided a nutritional basis and extended the utility of ACFS, which is a bridgehead for future cancer-preventive clinical trials using ACFS.

• Analytical Science and Technology
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• v.8 no.4
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• pp.881-886
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• 1995

Several forms of gangliosides have been separated from various types of biological matrices using cyclodextrin-modified capillary zone electrophoresis (CZE). Quantitative analysis of phospholipids from biological fluids was achieved by micellar electrokinetic capillary chromatography (MECC) using 35mM sodium dodecyl sulfate. Phosphorylation, one of the most important post-translational modifications of proteins at serine, threonine and tyrosine residues in small peptides were identified and quantitative analyses of phosphopeptides were performed. Seven different neuropeptides which are relative the pain reachanism in the vertebrate central nervons system were also separated by CZE.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.31 no.4
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• pp.169-190
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• 2020

The purpose of this paper is to analyze academic papers published by North Korean scientists, to uncover major areas of research in North Korean science and technology, and to uncover the intellectual structures that underlie these science and technology. Through quantitative analysis, it is to find out who the main research actors are, what research areas are being dealt with, which research areas last a long time, which areas have been discontinued, and which research areas are receiving new attention. In order to detect major research areas and intellectual bases in North Korean science and technology, North Korean scientists' articles were collected from WoS (SCIE). CiteSpace, a scientific quantitative analysis tool, was used to identify major research areas based on author simultaneous citation analysis. The main research areas in North Korea are found to be material properties, vibration analysis, incline matrice, sodium cointercalation, and external magnetic field.