• Title/Summary/Keyword: developing reagent

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Evaluation of developing efficiency on latent fingerprint (잠재지문 현출효율 평가에 대한 연구)

  • Kim, Man-Ki;Park, Sung-Woo;Ohgami, Yusuke
    • Analytical Science and Technology
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    • v.22 no.2
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    • pp.166-171
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    • 2009
  • Powder method is simple and very effective method for developing latent finger and palm print in crime scene. This technique has been actively studied to enhance effectiveness. In general, the evaluation for developing powder is mainly performed by the subjective opinion of researcher from comparison of the results obtained with existing and new one to develope finger and palm deposition. The purpose of this work is to present objective method of powder-treated latent fingerprint for evaluating method by developing efficiency. We indicated three evaluating methods of objective developing efficiency, which are measuring the number of minutiae in same sections on print, scattering level of developing reagent and contrast between developing reagent and background materials.

A Study on the Optimum Composition of Rose Bengal Reagent using Phase Transfer Catalyst (상이동 촉매 기법(phase transfer catalyst)을 이용한 rose bengal 시약의 최적 조성에 관한 연구)

  • Oh, Soo-Jin;Cha, Won-Jin;Choi, Da-Woon;Hong, Sung-Wook
    • The Journal of the Korea Contents Association
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    • v.18 no.7
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    • pp.245-252
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    • 2018
  • The rose bengal reagent, based on the phase transfer catalysis technique, is a calcium-targeting reagent that forms an insoluble salt that does not dissolve in a neutral or basic solution. It is expected to be effective in developing a latent fingerprint in a wet sample. However, many previous studies did not observe the fluorescence of the developed fingerprints, nor were the proposed methods of producing the reagents the optimal develop conditions. The aim of this study was to investigate the optimum reagent composition of rose bengal by varying the concentration of rose bengal dye and phase transfer catalyst based on maximum emission fluorescence of rose bengal. As a result, it was confirmed that rose bengal and surfactant concentration were the most effective when 0.01M: 0.008M, respectively.

Dual-purpose Reagent for Separating Paper with Tape and Developing Fingerprints on the Paper Simultaneously (종이에 부착된 테이프를 박리하는 동시에 지문을 현출하는 이중목적시약(dual-purpose)에 관한 연구)

  • Seo, Youn-Hee;Kim, Yeon-Ji;Shin, Min-Seop;Yu, Je-Seol
    • The Journal of the Korea Contents Association
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    • v.19 no.1
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    • pp.463-471
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    • 2019
  • Tapes are usually used in violent crimes and may contain important evidence. Separating adhesive side should be preceded to collect these evidence. In this study, we researched a novel dual-purpose reagent that can separate the tape without damaging and develop the fingerprints on porous surface when the tape is attached to A4 paper. As a result, the reagent of 1:2 ratio of 1,2-IND stock solution and HFE-7100 can separate without damaging the adhesive surface and develop fingerprints on separated A4 paper.

The Spectrophotometric Determination of Reducing Sugar in the Tobacco Leaves by losing a Color Developing Reagent, Blue Tetrazolium Chloride. (발색시약 Blue Tetrazolium Chloride를 이용한 잎담배중 환원당의 비색법적 정량.)

  • Lee, Mun-Su;Kim, Sin-Il
    • Journal of the Korean Society of Tobacco Science
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    • v.2 no.2
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    • pp.38-43
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    • 1980
  • The spectrophotometric determination oi reducing sugar in the tobacco leaves was carried out by employing blue tetrazolium chloride as a color developing reagent. The absorption maximum of formazan dye which is the product of the reaction between blue tetrazolium chloride and fructose was shown to be $530^{nm}$. In the fructose concentration range of 0.02mg/ml-0.14mg/ml the calibration curve was well coincided to the law of Beer-Lambert. In order to take a look at the accuracy and/or recovery rate of fructose determination, the standard fructose was added to the tobacco leaves and the concentration of this standard fructose was estimated. A tittle lower concentration of the standard fructose compared with the pure one in solution was observed. However, an excellent analytical recovery was revealed under the -2% of relative error limit. When we carried out the quantitative determination of this reducing sugar by the method of visual read-out (without using the spectrophotometer), the relative error was obtained to be $\pm$10%.

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Comparison of anti-oxidant activities of seventy herbs that have been used in Korean traditional medicine

  • Ko, Seong-Hee;Choi, Seong-Won;Ye, Sang-Kyu;Yoo, Sang-Ho;Kim, Hyun-Sook;Chung, Myung-Hee
    • Nutrition Research and Practice
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    • v.2 no.3
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    • pp.143-151
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    • 2008
  • Many herbs have been used as therapeutics in Korean traditional medicine. In view of their clinical indications, anti-oxidant activity may contribute to their pharmacological effects. However, anti-oxidant information on these plants has not been available. In this study, seventy herbs which have been used in Korean traditional medicine were selected and screened for anti-oxidant activity using their water extracts. The anti-oxidant activity was assessed by their ability to inhibit three oxidation reactions; luminol/Fenton reagent, 2, 7-dichlorodihydrofluorescein(DCHF)/Fenton reagent and DCHF/peroxynitrite. In each assay, 70 herbs were divided into two groups; anti-oxidant group which inhibited the respective oxidation reaction and was majority(about 60 herbs), and pro-oxidant group which enhanced the oxidation reaction but was minority(more or less 10 herbs). When the herbs were listed in the order of their anti-oxidant strength, the orders obtained from each assay were found to be quite similar. The upper top rankers(more or less 10 herbs) in each assay showed strong activity compared to the others. The uppermost rankers in each assay were Rubus coreanus Miquel/Rubus schizostylus(覆盆子), Schisandra chinensis Baillon/Schizandra chinensis(五味子) and Terminalia chebula Retziusl Terminalia chebula(訶子). Of the pro-oxidant herbs, about 4-5 herbs were strongly pro-oxidant, which enhanced the control oxidation reactions to 150-300%. But the meaning of this observation is not known since few of them in one assay were also anti-oxidant in other assays. The results obtained in the present study may serve as information for understanding pharmacological effects of these herbs and developing new drugs from them.

Comparison of Color-developing Methods for Phosphorus Analysis in Various Extractants for Soil Phosphorus (몇가지 토양인산(土壤燐酸) 추출용액(抽出溶液)의 인산(燐酸) 발색방법(發色方法) 비교(比較))

  • Yoon, Jung-Hui;Park, Baeg-Gyoon;Hwang, Ki-Sung
    • Korean Journal of Soil Science and Fertilizer
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    • v.31 no.2
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    • pp.114-119
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    • 1998
  • Intensity and stability of the blue color of phospho-molybdate complex in P analysis are known to be influenced by the matrix, reducing regent and acidity of the extractants. Objective of this research was to compare the efficiency of the color-developing reagents for P concentrations in distilled water and extracts of Lancaster, Mehlich II, and Mehlich III methods. Efficiencies on which to base this study were evaluated by the optimum ranges of P, reproducibility of calibration curve and stability of the developed color. Color-developing reagents employed were ammonium molybdate-1,2,4- aminonaphtholsulfonic acid (ANS), ammonium molybdate-ascorbic acid-bismuth subcarbonate (AB), and ammonium molybdate-ascorbic acid-antimony potassium tartarate (AA). The ANS revealed the lowest sensitivity but the widest ranges for P concentrations in color development. On the other hand, the AA bore the narrowest color-developing ranges and its sensitivity was similar to AB. However, at P concentrations lower than $0.5mg\;L^{-1}$, AA was more sensitive than AB. Based on the data on the ranges of calibration curve, stability of color and reproducibility of analytical data. AA reagent was considered to be suitable for the determination of P in distilled water and AB reagent was practically recommendable for soil P analysis in extracts by Lancaster, Mehlich II, and Mehlich III procedures.

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Vanillin의 신미량검출법 (제1보)

  • 이상섭;김용덕
    • YAKHAK HOEJI
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    • v.3 no.1
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    • pp.48-50
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    • 1957
  • The micro-assay methods of vanillin have been shown quite few, though several methods have been introduced for determination. A new sensitive micro-determination of vanillin, applying the yellow color reaction of vanillin and anillin, is shown in this paper. The absorption maximum of the yellow coloring matter, 4-Oxy-3-methoxy-henzal aniline, was 435 mu. The one dimensional ascending paper chromatographic method is applyed for isolation of vanillin from the mixed sample. The microdetection of vanillin is studied only in this paper. Vanillin was detected by the yellow spot on paper trip by the coloring reagent of aniline after several hours paper strip chromatographic at the following condition; paper strip ................ 2.5 X 35cm Whatman Filter Paper No.2 developing Solvent ......... petroleum-benzene-methanol n-butanol-water coloring agent ............. aniline. The Rf-value on petroleum benzene and methanol was 0.63 and that on n-butanol and water was 0.90. The minimum detectable amount of vanillin by this method was 10 micrograms. It is recommendable, if interference substances as aromatic aldehydes present, that the application of this aniline reaction and Foline Denis reaction on the same paper chromatogram is appreciable.

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Mechanical Properties and Microstructure of Ni-0.9wt%P Electroformed Layer (Ni-0.9wt%P 전주층의 기계적 특성 및 미세조직)

  • 정현규;서무홍;김정수;천병선;김승호
    • Journal of the Korean institute of surface engineering
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    • v.34 no.4
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    • pp.289-296
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    • 2001
  • Ni-P electroformed layers were investigated for developing a steam generator tube repair technology in PWRs. The effects of an additive, RPP (Reagent over Pitting Protection) and agitation on mechanical properties and microstructure of the layer were evaluated. The addition of the RPP showed to inhibit the formation of pores, to refine the grain size, and to increase the residual stress in the layer. However, the agitation of the solution during electroforming was observed to increase pores in local regions of the electroformed layer, resulting in decreasing its mechanical properties. The heat treatment of the layer at $343^{\circ}C$ for 1 hr. precipitated the very fine particles of Ni3P in the layer, which inhibited grain growth and increased microhardness.

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The Removal of Silver in the Fixer Wastewater of X-ray Film Using Manganese Dioxide (이산화망간을 이용한 x-ray 필름 정착폐액중의 은 제거)

  • 박정호;오성훈;전용보;임찬섭;박승조
    • Resources Recycling
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    • v.6 no.4
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    • pp.11-16
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    • 1997
  • The wastewater resulted from the process of developing and fuing for x-ray film manufachlring contains a lot of silvercomponent. The average concentation of silver-component is about 1,500 mgA. The wastewater contained silver-component is toxic when it is discharged to the natural ecosystem. So that we must to do pretreatment of wastewater prior to discharge. There are electrolysis. chemical precipitation, and metallic replacement as conventional lreabent proccss of fixer wastewater of x-ray film. Adsorption of silver-component in x-ray fkcr wastewater was carricd out this study. 'Ille manganese dioxide (MDO) reagent and the recovered manganese dioxide (RMDO) from the waste dry-cell were used for adsarbents. Adsorption of silvercomponent was wrried out at the batch and continuous type experimental equipment. The adsorption experiment results were obtained bom silver-component have some diifcrences according to adsorhents. The adsorption results of manganese dioxide reagent (MDO) were better ihan those of waste dry-ccU (RMDO), but the manganese dloxide recovered fmm waste dry-cell (RMDO) will be able la recognized as good adsorbent too.

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Enhancement of fingerprint in blood deposited on the surface of thermal paper by using the mixture of polyvinylpyrrolidone and 1,2-indanedione (Polyvinylpyrrolidone과 1,2-indanedione 혼합물을 이용한 감열지에 부착된 혈흔지문의 증강)

  • Kim, Dongman;Ryu, Heayeon;Jeong, Seunghoon;Joo, Inseon;Hong, Sungwook
    • Analytical Science and Technology
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    • v.34 no.3
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    • pp.122-127
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    • 2021
  • A mixture of polyvinylpyrrolidone and 1,2-indanedione (PVP-IND) is known to be the best reagent for developing latent fingerprints deposited on the surface of a thermal paper. However, no study has evaluated whether PVP-IND could enhance fingerprints in blood deposited on the surface of thermal paper. Therefore, in this study, the ability of PVP-IND to enhance the fingerprints in blood was investigated. Furthermore, aqueous amido black solution, which is known to be the best reagent for enhancing fingerprints in blood deposited on the surface of thermal paper, was used for comparison with PVP-IND. Therefore, while enhancing the fingerprints in diluted blood, PVP-IND enhanced the quality of fingerprints compared to aqueous amido black solution. The ridge diffused when the undiluted fingerprints in blood were enhanced with PVP-IND because PVP reacted with amino acids in blood; however, amido black solution yielded better results. When treated with PVP-IND, it is presumed that the ridge diffused due to the reaction of PVP and amino acids contained in the blood.