• Title/Summary/Keyword: Low-dye

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Facile Fabrication of $TiO_2$ Photoelectrodes Using Intense Pulsed Light for Dye-Sensitized Solar Cells

  • Jin, Hwa-Yeong;Yu, Gi-Cheon;Lee, Jin-A;Im, Jeong-A;Kim, Ji-Hyeon;Go, Min-Jae
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.02a
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    • pp.228-228
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    • 2013
  • Dye-Sensitized Solar Cells (DSSCs) have attracted great interests as they offer high energyconversion efficiencies at low cost. For the conventional fabrication of DSSCs, high temperature sintering is required for the construction of interconnect $TiO_2$. However, more simplified process which can be applicable to large-sized solar cells module, is strongly necessary for the commercialization of DSSCs. In this work, we developed novel sintering method using Intense Pulsed Light (IPL), which can replace the conventional high temperature sintering methods. The photovoltaic properties of DSSCs utilizing IPL methods will be reported.

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Natural Dyeing with Walnut Hull(II) - Dyeing Properties of Cotton - (호도외피를 이용한 천연염색(II) - 면섬유의 염색성 -)

  • Shin, Youn-Sook
    • Korean Journal of Human Ecology
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    • v.9 no.3
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    • pp.63-68
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    • 2006
  • Walnut colorants were extracted from walnut hull and their dyeing properties on cotton were investigated. Effect of dyeing conditions on dye uptake and effect of mordanting on dye uptake, color change and colorfastness were explored. Walnut colorants showed low affinity to cotton compared with wool and its isotherm adsorption curve was Freundlich type. It was considered that hydrogen bonding and van der Waal's force were involved in the adsorption of walnut colorants onto cotton. The dyed cotton showed YR color and there was no significant color change as pH changed. The dyed cotton showed generally high colorfastness except fastness to washing and light. Mordanting did not improve dye uptake and colorfastness, and not affect color of the dyed cotton significantly.

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Study of Dyeing Properties by Swelling Agent on meta-aramid Fiber with Cationic Dyes (Swelling agent에 따른 메타계 아라미드 섬유의 Cationic dye 염색특성)

  • Kim, Eun-Mi;Park, Chung-Won;Choi, Jae-Hong
    • Textile Coloration and Finishing
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    • v.24 no.1
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    • pp.1-7
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    • 2012
  • Dyeing and fastness characteristics of 100% meta-aramid fiber were investigated with cationic dyes and swelling agents under various dyeing conditions such as dyeing temperature and pH of dye bath. Dye exhaustion started at around $80^{\circ}C$ and settled down at $130^{\circ}C$. Among swelling agents used, N-methyl formanilide showed comparatively higher K/S values comparing to 1-phenoxypropan-2-ol. Under weak acidic conditions in the range pH 5 to 7, the exhaustion of cationic dyes could be enhanced leading to higher adsorption and stability of colorimetric property. Wash and rubbing fastness were generally good but low light fastness found can be attributable to the poor photo-stability of the cationic dyes.

AN EXPERIMENTAL STUDY ON THE APICAL MARGINAL LEAKAGE OF DIFFERENT OBTURATION METHODS (근관충전 방법에 따른 치근단부 근관의 변연 누출에 관한 연구)

  • Cho, Yong-Bum;Hong, Chan-Ui
    • Restorative Dentistry and Endodontics
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    • v.15 no.1
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    • pp.81-87
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    • 1990
  • The purpose of this study was to evaluate the apical seal produced by low temperature($70^{\circ}C$) injection gutta percha technique(ULTRAFIL) with & without sealer, warm latero-vertical cindensation technique (ENDOTEC) with & without sealer, and the lateral condensation technique with sealer. 100 extracted, single rooted human teeth were divided into 5 groups and root canals were enlarged & obturated according to the purpose of this study. Obturated teeth were immersed in 2.5% methylene blue for 48hrs. at $37^{\circ}C$ incubator and split. The apical sealing ability was evaluated by measuring the degree of dye penetration into the canal. The results were as follows: 1. All group showed varying depth of dye penetration. 2. There were no significant difference among Group I (lateral condensation), Group II (ULTRAFIL with sealer) & Group IV (ENDOTEC with sealer) (P>0.05). 3. There were less dye penetration when used in conjunction with sealer (P<0.001).

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Influence of a TiCl4 Treatment Condition on Dye-Sensitized Solar Cells

  • Kim, Jung-Kyu;Shin, Ka-Hee;Lee, Kun-Seok;Park, Jong-Hyeok
    • Journal of Electrochemical Science and Technology
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    • v.1 no.2
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    • pp.81-84
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    • 2010
  • In dye-sensitized solar cells (DSSCs), the back transfer of photo-generated electrons from FTO glass to triiodide ions in an electrolyte is an important loss mechanism, which leads to low cell efficiency. Recently, this back electron transfer was greatly suppressed by the introduction of a compact $TiO_2$ blocking layer, which was prepared by the treatment of $TiCl_4$ solution. In the present work, more detailed $TiCl_4$ treated surface conditions on FTO substrate were investigated and DSSC performances were correlated with the surface morphology as well as dark current behavior.

The modification of materials for flexible Dye-Sensitized Solar Cells

  • Kim, Chang-Ho;Han, In-Young;Kim, Jae-Hoon
    • 한국정보디스플레이학회:학술대회논문집
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    • 2009.10a
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    • pp.1560-1563
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    • 2009
  • We fabricated Dye-Sensitized Solar Cells(DSSCs) which are modified by using liquid crystals(LCs) and electro-deposition on cathode electrode in order to apply to flexible DSSCs. We deposited Pt metal layers on ITO electrode through the method of electro-deposition process during low-temperature. We could expect the long-term stability by using ionic liquid(IL) and liquid crystals(LCs). We can also see the enhancement of efficiency through orientation of LCs in gel-state electrolyte using liquid crystals at the DSSCs.

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Laccase Activity and Azo Dye Decolorization Potential of Podoscypha elegans

  • Pramanik, Satadru;Chaudhuri, Sujata
    • Mycobiology
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    • v.46 no.1
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    • pp.79-83
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    • 2018
  • Azo dyes containing effluents from different industries pose threats to the environment. Though there are physico-chemical methods to treat such effluents, bioremediation is considered to be the best eco-compatible technique. In this communication, we discuss the decolorization potentiality of five azo dyes by Podoscypha elegans (G. Mey.) Pat., a macro-fungus, found growing on the leaf-litter layer of Bethuadahari Wildlife Sanctuary in West Bengal, India. The fungus exhibited high laccase and very low manganese peroxidase activities under different culture conditions. Decolorization of five high-molecular weight azo dyes, viz., Orange G, Congo Red, Direct Blue 15, Rose Bengal and Direct Yellow 27 by the fungus was found to be positive in all cases. Maximum and minimum mean decolorization percentages were recorded in Rose Bengal (70.41%) and Direct Blue 15 (24.8%), respectively. This is the first record of lignolytic study and dye decolorization by P. elegans.

Dyeing of Polyvinyl Alcohol Fibers in Filament Yarn Form with Reactive and Vat Dyes

  • Rashad, Mahmood;Kim, Sam-Soo;Huh, Man-Woo;Yoon, Nam-Sik
    • Textile Coloration and Finishing
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    • v.19 no.5
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    • pp.17-23
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    • 2007
  • As polyvinyl alcohol(PVA) filament yarn is commercially used in many fields due to its high strength and modulus properties. This research was carried out to study the dyeing behavior of PVA and to find out appropriate dye for better dyeing. As the dyeing behavior of PVA fiber is similar to cellulose due to the same functional group, reactive and vat dyes were selected for the dyeing. Color strength of PVA fibers treated with vat dyes was found to be better than those with reactive dyes, because of the low fixation of reactive dye on fibers. Most of the reactive dye may became hydrolyzed, and flushed away with water in washing. Colorfastness to laundering was shown to be very high for both of the reactive-dyed and vat-dyed PVA fibers.

Tencel Dyeing by Natural Indigo Prepared from Dyer's Knotweed (천연인디고를 이용한 텐셀직물의 염색)

  • Shin, Youn-Sook;Son, Kyung-Hee;Yoo, Dong-Il
    • Journal of the Korean Society of Clothing and Textiles
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    • v.32 no.12
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    • pp.1963-1970
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    • 2008
  • Natural indigo dye in powder form was prepared by modifying traditional Niram method, using $Ca(OH)_2$ instead of baked oyster powder for precipitating indigo dye. The prepared dye was applied to dyeing Tencel fabrics to investigate the effect of experimental conditions for the optimization of dyeing process. The indigo dye powder contained 15.2%(w/w) of indigo content and 0.757%(w/w) of indirubin content on the basis of HPLC analysis. Maximum dye uptake was obtained at $60^{\circ}C$ for 20min. Almost saturated dye uptake was obtained at 2g/L of sodium hydrosulfite concentration up to 4g/L of indigo dye and then slowly increased for further increase of sodium hydrosulfite. Whereas at higher indigo dye concentration(8g/L) more than 3g/L of reducing agent concentration was required for obtaining the maximum dye uptake. At the same indigo dye and reducing agent concentration, K/S value of the sample dyed without sodium hydroxide(pH 5.75) was 15.19, much higher than one dyed in alkaline condition(K/S 5.76). There was no difference in colorfastness ratings among samples with different color strength. However, more fading was occurred for the sample with low color strength.

Production of Lignin Degrading Enzymes and Decolorization of Various Dye Compounds by Wood-Rot Fungi (목재 부후균의 리그닌 분해효소 활성과 염료 화합물의 탈색)

  • Jang, Tae-Won;Jun, Sang-Cheol;Ahn, Tae-Seok;Kim, Kyu-Joong
    • Korean Journal of Microbiology
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    • v.42 no.1
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    • pp.34-39
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    • 2006
  • Wood-rot fungi produce extracellular lignin-degrading enzymes, the best known of which are lignin peroxidase, Mn-peroxidase and laccase. In this experiment, some of them produced all of three enzymes. Many other wood-rot fungi produced one or two of those enzymes with various combinations. In this experiment, we tried to clarify the relationship between the pattern of enzyme production and degradative activity of several dye compounds. From the 36 strains of 23 species of wood-rot fungi, Mn-peroxidase activity was found in 30 strains of the fungi tested, whereas the activity of lignin peroxidase and laccase was detected in 11 strains and 12 strains of species, repectively, in Kirks low nitrogen media. In relation to the activity of lignin degrading enzymes and degradation of dye compounds, the white-rot fungi with three kinds of enzymes tested showed the best dye decolorizers. The fungi with Mn-peroxidase activity only decolorized poly R-478 and remazol brilliant blue R dye in proportion to the enzyme activity, while methylene blue, bromophenol blue and congo red dye were degraded in regardless of enzyme activity. Those dyes were degraded in relation to the growth rate of mycelium. Brown-rot fungi did not degrade all the dye compounds except bromophenol blue, in spite of moderate growth rate.