• Korean Journal of Food Science and Technology
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• v.37 no.4
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• pp.513-518
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• 2005

Capillary electrophoresis (CE) method was developed to determine (+)-catechin and (-)-epicatechin contents in grape seed ethanol extract. CE separation was achieved using 100 mM phosphate and borate buffer at pH 6.0 as background electrolyte and fused silica capillary with 50 microns x 375 microns O.D. (effective length 20.0cm) maintained at $25^{\circ}C$. The applied voltage was 10kV, and detection was performed by DAD at 210 nm, Two catechins were well separated within 6 min with repeatability of <0.8% RSD for migration time and <2.0% RSD for peak area, and correlation coefficients higher than 0.994 were obtained from 58.0 to 174.0 mg/L with detection limit of 0.035 mg/L. Separated compounds were successfully determined. CE method was easy to handle and showed good reproducibility. CE method was compared with conventional coloring and HPLC methods, and main advantages of CE method were low amount of sample required, simple pre-sample treatment, good recovery rate, and short analysis time.

• The Journal of Internal Korean Medicine
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• v.14 no.1
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• pp.26-34
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• 1993

• YAKHAK HOEJI
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• v.21 no.1
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• pp.27-29
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• 1977

Amoxicillin formed blue color when heated with phophomolybdic acid in adequate condition, and the color showed maximal absorbance at 760nm. Effect of pH, concentration of phosphomolybdic acid and reating time were studied. And a new colorimetric method of determination of amoxicillin was developed.

• Korean Journal of Food Science and Technology
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• v.6 no.2
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• pp.56-60
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• 1974

A survey of the available methods for the determination of piperine was made, and a new method, developed based upon alkaline hydrolysis at about $140^{\circ}C$ followed by colorimetric determination of the liberated piperidine. Piperidine on treatment with p-nitrophenyl diazonium fluoborate reagent gives a red colored complex which has an adsorption maximum at 530nm. The method measures the total pungency in pepper and applicaple to piperine of black pepper and oleoresin of black pepper. The advantage of the present method is that the pungent compounds can be determined in micro samples.

• Korean Journal of Food Science and Technology
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• v.13 no.2
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• pp.142-145
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• 1981

A modified hydroxamate method was developed for determination of fat content in milk. Fat globules in milk were destroyed by adding ethanol and diethyl ether, and a homogeneous reaction system was obtained. The homogenate was reacted with hydroxylamine, milk fat formed ferric hydroxamate chelates which had red-purple color, and the ferric hydroxamate chelates was analyzed colorimetrically. This method was simpler than original hydroxamate method and comparable with the Babcock method in accuracy.

• Restorative Dentistry and Endodontics
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• v.35 no.5
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• pp.387-394
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• 2010

Objectives: The purpose of this study was to evaluate the whitening efficacy and longevity of home bleaching. Materials and Methods: A total of 28 patients were divided into either experimental group (Opalescence F; 15% carbamide peroxide) or control group randomly. The patients in experimental group were instructed to wear individual trays applied with bleaching gel for 2 hours a day for 4 weeks. Any treatments weren't applied to the patients in control group. The color measurements of central incisors, lateral incisors & canines of upper and lower arch were recorded at base line, immediately after the finishment of treatmemt (4 weeks), 8 weeks and 12 weeks using Colorimeter (Chroma Meter, 2600d Konica Minolta co.) and Vitapan classical shade guide (Vita Zahnfabrik). Results: A significantly stronger color change was observed for overall teeth samples in experimental group immediately after treatment (at 4 weeks) compared to ones in control group (p < 0.05). There was also a significant difference between baseline and 8 weeks or 12 weeks separately though color rebouncing phenomenon occurred as time went by (p < 0.05). Conclusions: The clinical effecacy and longevity of home bleaching without combined application of in-office bleaching was observed through this experiment.

• Journal of the korean academy of Pediatric Dentistry
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• v.42 no.1
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• pp.30-37
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• 2015

A new colorimetric test ($Cariview^{(R)}$) using a new type of pH indicator can reflect the acidogenic potential of plaque bacteria. The objective of this study was to evaluate the correlation between $Cariview^{(R)}$ and the caries experience (measured through the dmft index) of children, and to compare $Cariview^{(R)}$ with Dentocult $SM^{(R)}$. Having obtained informed consent, 135 children less than 6 years old participated in the study. We examined their dmft index, and performed two caries activity tests ($Cariview^{(R)}$ and Dentocult $SM^{(R)}$) according to the manufacturers' instructions. In the results, $Cariview^{(R)}$ showed a moderate correlation with the dmft index (r = 0.43, p < 0.01). $Cariview^{(R)}$ showed a sensitivity of 68.8%, a specificity of 69.2%, and an area under curve of 0.686 in the ROC curve analysis. $Cariview^{(R)}$ had a significant correlation with the children's caries experience and had a slightly better explanatory ability than Dentocult $SM^{(R)}$. Furthermore, $Cariview^{(R)}$ was convenient and easy to use on uncooperative children, and also had an educational effect with its visual colors. It is suggested that $Cariview^{(R)}$ could be used clinically to identify the children susceptible to develop caries and to establish a preventive strategy.

• Journal of the korean academy of Pediatric Dentistry
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• v.45 no.2
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• pp.162-169
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• 2018

The purpose of this study was to compare the validity of $Cariview^{(R)}$, a new colorimetric caries activity test, with $CRT^{(R)}$ bacteria, a conventional bacterial culture method. In addition, this study assesses the correlation between the dental caries experience and activity between mothers and their children. 34 pairs of mothers and their children under the age of 6 years participated in this study with informed consent. After filling out a questionnaire and oral examination, the two caries activity tests above were performed on each subject. In the results, $Cariview^{(R)}$ scores were statistically significant with children's caries experience (r = 0.598, p < 0.01) and showed higher correlation than $CRT^{(R)}$ bacteria scores. $Cariview^{(R)}$ scores showed statistically significant correlation with the number of decayed teeth in both mothers and children (p < 0.05). In both $Cariview^{(R)}$ and $CRT^{(R)}$ bacteria tests, there was no statistically significant correlation between caries experience and caries activity (p > 0.05). $Cariview^{(R)}$ colorimetric test will be clinically useful for predicting future caries risk and establishing a preventative strategy in pediatric dentistry.

• Korean Journal of Soil Science and Fertilizer
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• v.33 no.5
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• pp.369-375
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• 2000

To find a quick test procedure for soil nitrate concentration, two methods, i.e. "Nitracheck 404" reflectometer (Eijkelkamp, Netherlands) with nitrate test strip and a portable colorimeter "Hanna Ion Specific meter(USA) with a color development reagent, were tested for twenty soils with different nitrate contents ranged between from $10mg\;kg^{-1}$ to $340mg\;kg^{-1}$. The standard deviation, coefficient of variability, and recovery from these quick test procedures were compared with those measured by conventional Kjeldahl distillation method and nitrate ion electrode method. The nitrate concentration measured by portable colorimeter method was higher in soils with low concentration and lower in soils with high concentration than those measured by conventional methods. However, concentrations measured by test strip reflectometer method was showed the similar coefficient of variability and recovery as those by conventional methods for all soil samples. From the experimental results in this study, the test strip reflectometer method was thought to be recommendable one revealed the satisfied results for accuracy, quickness, and simplicity for field test of soil nitrate concentration.

• Journal of the korean veterinary medical association
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• v.19 no.1
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• pp.54-61
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• 1983

The present paper describes a simple colorimetric determination method of serum or plasma free fatty acids in various animal for those who are in the laboratories unequiped with high-cost newer analysing equipments and for those clinicians with low-cost a