• Journal of Pharmaceutical Investigation
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• 제15권3호
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• pp.151-159
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• 1985

For the determination of aliphatic carbamates, the quantitative analysis of carisoprodol was investigated by gab chromatography (GC) and spectrophotometry. All the methods studied were found to be very quantitative. The minimum experimental amounts of GC method, spectrophotometric method I and II were approximately $10^{-9},\;10^{-5}$ and $10^{-8}$ mole, respectively. The obtained results showed that GC method I was much more sensitive and rapid than spectrophotometric method II.

• 대한화학회지
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• 제12권2호
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• pp.51-54
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• 1968

Rapid flame spectrophotometric method is developed to determine a small amount of sodium in zircon frit and high purity zirconium compounds. The instrumental characteristics and the optimum conditions are studied and a comparison between calibration curve method and standard addition method is made.

• 대한화학회지
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• 제68권1호
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• pp.20-24
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• 2024

This article presents the advantages of utilizing gossypol and its derivatives as reagents for iron (III) (Fe (III)) ions. A novel spectrophotometric method has been developed for the determination of Fe (III) using gossypol derivatives in the presence of a universal buffer solution. Optimal conditions have been identified, and the composition and stability constants of the Fe (III) complex with gossypolacetic acid have been determined.

• 한국토양비료학회지
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• 제32권3호
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• pp.268-273
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• 1999

토지이용 유형과 유효인산 함량이 다양한 56개 토양을 대상으로 범용 분광광도계를 사용한 Lancaster법과 분석과정 및 측정과정을 간편화시킨 Soiltek$^{(R)}$ KA-1에서 제시하는 방법으로 측정한 유효인산함량에 대하여 정확도 및 정밀도를 비교 분석하였다. 두 방법으로 분석된 인산함량은 고도의 유의성 있는 정의상관 ($r=0.998^{***}$)을 보였으며, 기울기는 0.97로 거의 일치하여 두 방법간의 정확성은 차이가 없었다. 또한, 두 방법으로 측정된 인산함량 분석결과의 표준편차, CV, 상대정밀도(RS)는 거의 차이가 없으므로 정밀도에서도 차이가 없었다. 따라서, 분석과정 및 기기조작의 편리성 및 신속성을 고려한다면 Soiltek$^{(R)}$ KA-1에서 제시하는 방법으로 유효인산 함량을 측정하는 것도 유용한 방법이라고 생각된다.

• Restorative Dentistry and Endodontics
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• 제47권1호
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• pp.8.1-8.9
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• 2022

Objectives: The aim of this study was to compare the color change of the Giomer resin composite (Beautifil-Bulk) by using photographs obtained with a smartphone (iPhone 6S) associated with Adobe Photoshop software (digital method), with the spectrophotometric method (Vita Easyshade) after immersion in different pigment solutions. Materials and Methods: Twenty resin composite samples with a diameter of 15.0 mm and thickness of 1.0 mm were confectioned in A2 color (n = 5). Photographs and initial color readings were performed with a smartphone and spectrophotometer, respectively. Then, samples were randomly divided and subjected to cycles of immersion in distilled water (control), açai, Coke, and tomato sauce, 3 times a day, 20 minutes for 7 days. Later, new photographs and color readings were taken. Results: The analysis (2-way analysis of variance, Holm-Sidak, p < 0.05) demonstrated no statistical difference (p < 0.005) between the methods in all groups. Similar color changes were observed for all pigment solutions when using the spectrophotometric method. For the digital method, all color changes were clinically unacceptable, with distilled water and tomato sauce similar to each other and with statistical differences (p < 0.005) for Coke and açai. Conclusions: Only the tomato sauce produced a color change above the acceptability threshold using both methods of color assessment. The spectrophotometric and digital methods produce different patterns of color change. According to our results, the spectrophotometric method is more recommended in color change assessment.

• 생약학회지
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• 제33권3호통권130호
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• pp.182-186
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• 2002

The Coptidis rhizoma is known for containing protoberberine alkaloids. Berberine, coptisine and palmatine are the major constituents of protoberberine alkaloids. The alkaloids were isolated and determined by forming complex compounds from Coptidis rhizoma in preparation I(Sam-Hwang-Sa-Sim-Tang) and II(Hwang-Ryen-Tang). For the determination of these alkaloids, a new spectrophotometric method was developed with a simple and selective sample clean-up using thiocyanatocobaltate[II] complex compound ion. The absorbance of alkaloidal complex compounds in l.2-dichloroethane solution was measured at 625 nm. Calibration curve for the alkaloids isolated from Coptidis rhizoma was linear over the concentration range of 0.2-0.3 mg/ml. The method was proved to be rapid, simple and reliable for the isolation and the determination of the alkaloids in Coptidis rhizoma preparation I and II.

• 대한화장품학회지
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• 제22권1호
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• pp.84-101
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• 1996

동물시험을 최소화 하고, 동물시험에 사용되는 노력과 비용을 줄이기 위해 동일한 동물에서 광독성과 광알러지성을 함께 보는 새로운 방법을 제안하고, in vitro alternatives로서 photostability와 spectrophotometric carbonyl assay의 유용성을 검토하였다. Modified photosensitization model에서는 Ichikawa 방법과는 달리 동물수, 휴식 기간, 첩포 횟수를 단순히하고 폐쇄 첩포를 추가하였다. 방법의 유용성을 보기 위해 Benzocaine, 6-methyl coumarine을 Ichikawa 방법 및 본 시험 방법으로 결과를 비교한 결과 macroscopic, histologic examination에서 비슷한 결과를 얻었다. Photostability 시험에서는 pbotoreactive agent 들이 모두 20%이상의 흡광도 감소를 보여 pbotosensitization potential을 측정하기 위한 전 단계 실험으로서의 가능성을 보여주었고, spectrophotometric carbonyl assay에서는 salmonella를 이용한 광독성 실험에서는 나타나지 않았던 저농도의 Amthracene, Hematoporphyrin에서 조차도 phtotoxic prtential을 보여주어 in vitro alternatives로서의 가능성을 보여주었다.

• Journal of Periodontal and Implant Science
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• 제53권4호
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• pp.295-305
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• 2023

Purpose: Various methods have been proposed to achieve the nearly complete decontamination of the surface of implants affected by peri-implantitis. We investigated the in vitro debridement efficiency of multiple decontamination methods (Gracey curettes [GC], glycine air-polishing [G-Air], erythritol air-polishing [E-Air] and titanium brushes [TiB]) using a novel spectrophotometric ink-model in 3 different bone defect settings (30°, 60°, and 90°). Methods: Forty-five dental implants were stained with indelible ink and mounted in resin models, which simulated standardised peri-implantitis defects with different bone defect angulations (30°, 60°, and 90°). After each run of instrumentation, the implants were removed from the resin model, and the ink was dissolved in ethanol (97%). A spectrophotometric analysis was performed to detect colour remnants in order to measure the cumulative uncleaned surface area of the implants. Scanning electron microscopy images were taken to assess micromorphological surface changes. Results: Generally, the 60° bone defects were the easiest to debride, and the 30° defects were the most difficult (ink absorption peak: 0.26±0.04 for 60° defects; 0.32±0.06 for 30° defects; 0.27±0.04 for 90° defects). The most effective debridement method was TiB, independently of the bone defect type (TiB vs. GC: P<0.0001; TiB vs. G-Air: P=0.0017; TiB vs. GE-Air: P=0.0007). GE-Air appeared to be the least efficient method for biofilm debridement. Conclusions: T-brushes seem to be a promising decontamination method compared to the other techniques, whereas G-Air was less aggressive on the implant surface. The use of a spectrophotometric model was shown to be a novel but promising assessment method for in vitro ink studies.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2001년도 학술발표회 발표논문집
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• pp.421-425
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• 2001

Among the many parameters describing water quality, total nitrogen content(TN) is regarded as important one in relation to water quality management of the waterbodies for its role in eutrophication process. This study evaluated for accuracy, convenience and promptness of nitrogen analysis methods : (1)UV spectrophotometric method, (2)summation method, (3)cadmium reduction method. And, the detection limit of each method was calculated using EPA method. The UV spectrophotometric method after oxidation appears to be more convenient and accurate in determination of the TN contents than the summation method and cadmium reduction method. The summation method is necessary to separate determinations of the organic nitrogen, ammonia, nitrite, and nitrate. And, because summation method has many other methods for each contents, it can be detected for wide range of concentration.

• 한국해양학회지:바다
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• 제25권4호
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• pp.81-96
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• 2020

해수 중 용존 암모늄 분석에는 Berthlot's 반응의 분광광도법이 일반적으로 사용되었으나, 최근에는 OPA (orthophthaldialdehyde-sulfite) 형광시약을 이용한 형광법이 국제적으로 활발하게 사용되고 있다. 본 연구에서는 2017년도 호주연구선 Investigator에서 수행된 국제 영양염 선상 상호비교 실험에서 두 기관(KIOST(분광광도법, 1차 선형 회귀식 기울기만 사용), 호주CSIRO(형광법, 2차 비선형 회귀식 사용))간의 영양염 표준물질과 현장 해수시료의 용존 암모늄 농도값 차이(약 0.31 𝜇M)의 원인을 이해하기 위해 분석방법 간 검출한계, 분광광도법에 내재된 시약 굴절률, 검량선식 등에 의한 영향을 고찰하였다. 본 연구에서 측정된 분광광도법의 방법검출한계(0.063 𝜇M)와 시약 굴절률 바탕값(0.054 𝜇M)은 두 기관의 용존 암모늄 농도값 차이를 각각 20%, 17% 정도 설명할 수 있었다. 그러나 분광광도법의 검량선을 형광법과 동일한 2차식 또는 선형회기식의 기울기와 절편으로 농도를 계산할 경우, 두 기관 간의 용존 암모늄 농도값 차이는 현장에서 측정된 분광광도법의 방법검출한계 이하로 줄었다. 따라서 국제 영양염 선상 상호비교 실험에서 영양염 표준물질과 해수 현장시료에서 나타난 두 기관 간의 용존 암모늄 농도값 차이는 분광광도법과 형광법의 분석방법 차이에 의한 영향보다는 두 방법에 사용된 상이한 검량선식 영향인 것으로 판단된다. 향후 해수시료의 용존 암모늄 자료를 비교할 때 분석방법의 차이보다는 분석에 사용된 기저선, 표준용액열 개수, 검량선식 등에 대한 정보에 유의할 것을 권장한다.