• Title/Summary/Keyword: Colorimetric Properties

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Estimating dehalogenation reactivity of nanoscale zero-valent iron by simple colorimetric assay by way of 4-chlorophenol reduction

  • Mines, Paul D.;Kaarsholm, Kamilla M.S.;Droumpali, Ariadni;Andersen, Henrik R.;Hwang, Yuhoon
    • Environmental Engineering Research
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    • v.25 no.2
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    • pp.197-204
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    • 2020
  • A number of different nanoscale zero-valent iron (nZVI) materials have been prepared and compared depending on the desired properties for the particular application, but different physicochemical properties of this prepared nZVI make it difficult to universally compare and standardize them to the same scale. In this study, we aimed to demonstrate a simple microplate-based colorimetric assay using 4-chlorophenol as an indicator with respect to the remediation of real treatment targets, such as trichloroethylene (TCE), 1,1,1-trichloroethane (TCA), and atrazine. Effect of nickel contents on 4-chlorophenol reduction was successfully investigated by the miniaturized colorimetric assay. In the same manner, the effect of nickel contents on dehalogenation of TCE, TCA, and atrazine was investigated and the pseudo-first-order kinetic constants were compared with the results for 4-chlorophenol. The similar pattern could be observed between 4-chlorophenol reduction obtained by colorimetric assay and TCE, TCA, atrazine reduction obtained by a traditional chromatographic method. The reaction kinetics does not match perfectly, but the degree of reaction can be estimated. Therefore, the colorimetric assay can be a useful and simple screening tool to determine nZVI reactivity toward halogenated organics before it is applied to a particular remediation site.

Application of Colorimetric Method for Evaluation of Apparent Chloride Diffusion Coefficient of Concrete (콘크리트 중 겉보기 염소이온 확산계수 추정을 위한 비색법의 적용)

  • 문한영;김홍삼;최두선;오세민
    • Proceedings of the Korea Concrete Institute Conference
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    • 2003.11a
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    • pp.541-544
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    • 2003
  • Chloride diffusivity is one of the important properties of concrete affecting the durability of a structure. The diffusivity for porous materials is determined conventionally by immersion in a solution. However, this method is complicate and time-consuming, often requiring months or years to obtain results. Thus, the application of colorimetric method to estimate the apparent diffusivity of chloride ion was verified in this study. The result reveals that the apparent diffusivity of chloride ion can be predicted to use colorimetric method. Additionally the colorimetric method is capable to predict the profile of chloride ion.

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Effects of Colorimetric Properties and Color Sensibility Factors on Color Preferences for Green Yellow Natural Dyed Silk Fabrics: Focused on Combination Dyeing with Indigo and Japanese Pagoda Tree (연두색 천연염색 견직물의 색채특성과 감성요인이 선호도에 미치는 영향: 쪽과 괴화의 복합염색을 중심으로)

  • Shin, Judong;Kim, Yeowon;Choi, Jongmyoung
    • Science of Emotion and Sensibility
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    • v.21 no.1
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    • pp.143-154
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    • 2018
  • This study was performed in order to suggest useful data for color planning of eco-friendly and sensible fashion products. Silk fabrics were dyed in combination with natural indigo and Japanese pagoda tree and were treated with four kinds of mordants after combination dyeing. Then, their colorimetric properties were evaluated. From these composite-dyed silk fabrics, color sensibilities and color preferences of green yellow (GY) color were evaluated among the female university students, and thus, the influences of colorimetric properties and color sensibilities on color preferences were analyzed. When the silk fabrics were dyed in the combination of natural indigo and Japanese pagoda tree and were treated without mordants, they turned green color when indigo 10 g/L was used, and blue-green when indigo 20 g/L was added. And when they were dyed in combination of natural indigo and Japanese pagoda tree and were treated with four kind of mordants after combination dyeing, they turned GY color in almost all cases. The color sensibilities of the GY silk fabrics with the combination dyeing of indigo and Japanese pagoda tree, were classified into three factors: pleasantness, gracefulness, and comfort. Color sensibility factors showed significant differences according to the concentration of indigo and the kinds of mordants. There were almost significant relationships between colorimetric properties and color sensibilities factors of compositely dyed GY silk fabrics. The color preferences of the GY fabrics, which were dyed in the combination of using natural indigo and Japanese pagoda tree and four kinds of mordants, were found to be predicted by the color sensibility in a regression model.

APPLICATION OF TIN ION-PLATING TO THE ORTHODONTIC APPLIANCE (교정용 장치물에 대한 TiN Ion Plating의 응용)

  • Kwon, Oh-Won;Kim, Kyo-Han
    • The korean journal of orthodontics
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    • v.21 no.1 s.33
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    • pp.7-16
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    • 1991
  • To estimate the possibility of the application of TiN ion-plating to the orthodontic appliance, colorimetric properties, and characteristics of ion-plated film as well as adhesive strength of TiN film to the substrate and mechanical properties of ion-plated orthodontic appliance were investigated. The obtained results were as follows: 1) TiN ion-plated film had the colorimetric properties which were the hue of about 2.5 Y, the brightness of about 6, and the chroma of about 4 by the standard color chip of JIS. 2) TiN ion-plated film was $2{\mu}m$ in thickness and its deposition pattern was rather irregular. 3) TiN phase was confirmed on the X-ray diffraction pattern. 4) Critical load for delamination of ion-plated film from stainless steel band was 10N. 5) Tensile and yield strength of ion-plated specimen was increased about 10Kg $f/mm^2$, while elongation was decreased $1\%$ compairing to the values of the non ion-plated specimen.

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COLLOIDAL PROPERTIES OF HOLLOW LATICES AND THEIR ROLES IN CONTROLLING COLORIMETRIC PARAMETERS OF COATED PAPER SURFACE

  • Hitomi HAMADA;Yoko SAITO
    • Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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    • 1999.04b
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    • pp.309-314
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    • 1999
  • With a view to seek the influence of hollow sphere pigments of latex upon the printed color on coated paper surface, the hollow sphere pigments were compared with filled ones in a variety of experimental approaches. Colloidal properties of latices were determined by measuring zeta potential and particle size distribution. For the amphoteric filled sphere pigment of latex, the polarity was reversed from the negative side to the positive side with decreasing pH. An extraordinarily high peak in the particle size distribution of the amphoteric filled evidenced aggregation between latex particles near the isoelectric point, depending on the electrolyte concentration and pH of the suspending medium. Coated papers containing the hollow sphere pigment in their coating improved optical properties like gloss and brightness. Optical parameters solely of the coating could account for this finding. An equation derived from the Kubelka-Munk equation calculated them fro twice measurements of reflectance of a coated paper over two substrates of different reflectances. This method permitted to predict brightness of coated paper of which coat weight would be different fro the actual one. The colorimetric parameters of solid-printed surfaces of the coated papers closely related to optical and structural properties of the coated papers. The color of the printed surfaces was dominated by the brightness and the smoothness of the coated papers. The hollow sphere pigments were proved to improve optical properties of coated paper and to control minutely colorimetric parameters of printed surfaces.

Teaching a Known Molecule New Tricks: Optical Cyanide Recognition by 2-[(9-Ethyl-9H-carbazol-3-yl)methylene]propanedinitrile in Aqueous Solution

  • Tang, Lijun;Zhao, Guoyou;Wang, Nannan
    • Bulletin of the Korean Chemical Society
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    • v.33 no.11
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    • pp.3696-3700
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    • 2012
  • The colorimetric and fluorescent cyanide recognition properties of 2-[(9-ethyl-9H-carbazol-3-yl)methylene]-propanedinitrile (1) in $CH_3CN-H_2O$ (2/1, v/v, HEPES 10 mM, pH = 7.0) solution were evaluated. The optical recognition process of probe 1 exhibited high sensitivity and selectivity to cyanide ion with the detection limit of $2.04{\times}10^{-6}$ M and barely interfered by other coexisting anions. The sensing mechanism of probe 1 is speculated to undergo a nucleophilic addition of cyanide to dicyanovinyl group present in compound 1. The colorimetric and fluorescent dual-modal response to cyanide makes probe 1 has a potential utility in cyanide detection.

Determination of Cholesterol by a Diode Laser/Fiber Optic Colorimetric Spectrometer

  • Kim, Seong Ho;Nam, Seong Man;Byeon, Sang Gil;Yun, Sin Yeong;Hong, Seong Sik
    • Bulletin of the Korean Chemical Society
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    • v.21 no.4
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    • pp.389-392
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    • 2000
  • A simple and inexpensive colorimetric spectrometer for determining total cholesterol has been developed,comprising a diode laser as the light sourcoptical fibers for the light guide and a photodiode as the detector.The stabilty and performance of the new system was investigated by obtaining the calibration curve for stan-dard cholesterol solutions. The total cholesterol in humanserum was also measured by the analyzer and com-pared with the value obtained by a conventional spectrometer. The results showed that the developed spectrometer was useful for the determination of cholesterol levels. The visible diodelaser used in the study exhibited good spectroscopic and operational properties for colorimetric absorption spectrometry and could be a key component for the development of a simple and economical analyzer.

Colorimetric Determination of pH Values using Silver Nanoparticles Conjugated with Cytochrome c

  • Park, Jun-Su;Choi, In-Hee;Kim, Young-Hun;Yi, Jong-Heop
    • Bulletin of the Korean Chemical Society
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    • v.32 no.9
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    • pp.3433-3436
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    • 2011
  • Some of metal nanoparticles have the potential for use as colorimetric assays for estimating solution properties, such as pH and temperature due to localized surface plasmon (LSP) phenomena. This report describes the use of silver nanoparticles (AgNP) conjugated with cytochrome c (Cyt c) for the colorimetric determination of solution pHs. When the pH of a solution decreases, the Cyt c immobilized on the AgNP undergoes a conformational change, leading to a decrease in the interparticle distance between Cyt c-AgNP probes and consequent red-shift in LSP. As a result, the color of the Cyt c-AgNP probe solution changes from yellow to red and finally to a grayish blue in the pH range from 11 to 3. This gradual color change can be used to determine the pH of a solution over a wide pH range, compared to other colorimetric methods that use gold nanoparticles.