• Bulletin of the Korean Chemical Society
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• 제30권3호
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• pp.556-560
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• 2009

Aggregation behavior of three kinds of benzindocarbocyanine dyes in aqueous methanol solution was studied by UV-Vis absorption spectrum. The results indicated that the three dyes all existed monomer-dimer equilibrium in aqueous methanol solution (concentration range $10^{−5}\;to\;10^{−6}$ M) at 25.0$\sim$41.0 ${^{\circ}C}$ for Dye 1, 28.0$\sim$49.0 ${^{\circ}C}$ for Dye 2 and 26.0$\sim$47.0 ${^{\circ}C}$ for Dye 3. The fundamental property of the three dyes as the dimeric association constant KD, the dimeric free energy ${\Delta$}G_D, the dimeric entropy ${\Delta$}S_D, and the dimeric enthalpy ${\Delta$}H_D were determined. The ${\Delta$}H_D of three dyes: Dye 1, Dye 2 and Dye 3 was -42.5, -15.1 and -18.9 kJ/mol, respectively. The experimental observations were the subject of a theoretical study including the ground-state geometries which were fully optimized using DFT at B3LYP/6-31G level. The effect of dye molecule structure on ${\Delta$}H_D was discussed by theoretical calculations.

• Bulletin of the Korean Chemical Society
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• 제34권7호
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• pp.2093-2098
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• 2013

Density functional theory (DFT) was used to determine the ground state geometries of indigo and new design dyes (IM-Dye-1 IM-Dye-2 and IM-Dye-3). The time dependant density functional theory (TDDFT) was used to calculate the excitation energies. All the calculations were performed in both gas and solvent phase. The LUMO energies of all the dyes were above the conduction band of $TiO_2$, while the HOMOs were below the redox couple (except IM-Dye-3). The HOMO-LUMO energy gaps of new design dyes were smaller as compared to indigo. All new design dyes were strongly red shifted as compared to indigo. The improved light harvesting efficiency (LHE) and free energy change of electron injection ${\Delta}G^{inject}$ of new designed sensitizers revealed that these materials would be excellent sensitizers. The broken coplanarity between the benzene near anchoring group having LUMO and the last benzene attached to TPA unit in all new design dyes consequently would hamper the recombination reaction. This theoretical designing will the pave way for experimentalists to synthesize the efficient sensitizers for solar cells.

• Membrane and Water Treatment
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• 제7권1호
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• pp.23-38
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• 2016

Batch adsorption of methyl orange (MO) from aqueous solution using three kinds of anion exchange membranes BI, BIII and DF-120B having different ion exchange capacities (IECs) and water uptakes ($W_R$) was investigated at room temperature. The FTIR spectra of anion exchange membranes was analysed before and after the adsorption of MO dye to investigate the intractions between dye molecules and anion exchange membranes. The effect of various parameters such as contact time, initial dye concentration and molarity of NaCl on the adsorption capacity was studied. The adsorption capacity found to be increased with contact time and initial dye concentration but decreased with ionic strength. The adsorption of MO on BI, BIII and DF-120B followed pseudo-first-order kinetics and the nonlinear forms of Freundlich and Langmuir were used to predict the isotherm parameters. This study demonstrates that anion exchange membranes could be used as useful adsorbents for removal of MO dye from wastewater.

• 한국염색가공학회지
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• 제19권2호
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• pp.32-35
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• 2007

Cyclodextrin is a cyclic oligosaccharid material which shows an ability to incorporate organic guest molecules inside their cavity area. Thus, this ${\beta}-cyclodextrin$ treatment on fiber substrates may provide the changed surface characteristics of the substrates such as solubility, chemical reactivity and spectral property. In this context, the aim of this present work is to make a bridge connection using hetero-bi-functional reactive dye between fiber substrates and ${\beta}-cyclodextrin$. In addition, the corresponding Berberine inclusion behaviors into the inner cavity of ${\beta}-cyclodextrin$ was examined. The %exhaustion of Berberine inclusion as a guest molecule within the ${\beta}-cyclodextrin$ was measured using UV-Vis spectrophotometer. The findings showed that the %exhaustion of Berberine inclusion increased with increasing the prepared dye bridge compound and ${\beta}-cyclodextrin$ host material.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 춘계학술대회 초록집
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• pp.57.1-57.1
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• 2010

Development of low cost hybrid functional nano-structured materials has great interest to enhance sensitivity of dye-sensitized solar cells and reduction of the production cost. In this talk we will discuss about using different processes to modify functional characteristics of photoelectrode and investigate effects of chemical modification without significant structural variation on to enhance performance of DSSCs. Efficient electron transportation between dye molecules and photoelectrode has been obtained by appropriate chemical modification and efficiency of DSSC has been significantly improved. A comparative analysis on effects of surface functional and electron states of photoelectrode on VOC and JSC has been also carried out to discuss effects of composite materials on physical structure and electronic properties to correlate enhanced performance of these devices.

• Bulletin of the Korean Chemical Society
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• 제34권8호
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• pp.2276-2280
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• 2013

The accurate prediction of vertical excitation energies is very important for the development of new materials in the dye and pigment industry. A time-dependent density functional theory (TD-DFT) approach coupled with 22 different exchange-correlation functionals was used for the prediction of vertical excitation energies in the halogenated copper phthalocyanine molecules in order to find the most appropriate functional and to determine the accuracy of the prediction of the absorption wavelength and observed spectral shifts. Among the tested functional, B3LYP functional provides much more accurate vertical excitation energies and UV-vis spectra. Our results clearly provide a benchmark calibration of the TD-DFT method for phthalocyanine based dyes and pigments used in industry.

• 한국염색가공학회지
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• 제16권2호
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• pp.15-24
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• 2004

The antibiotic reactive dye was synthesized by coupling of reactive chromagen with diazotised silver sulfadiazine for an antibiotic property. The highly reactive MCT(monochlorotriazine) and DCT (dichlorotriazine) type functional groups which have heterocyclic ring and moderately reactive VS-type dye that has good dyeability were used for reactivity. The synthesized antibiotic reactive dye is expected to impart the antibiotic function with high durability on cotton fabric only by one-step dyeing process without further finishing treatment. The synthesis of antibiotic dye was easily proceeded thorough diazotisation of silver sulfadiazine and coupling with suitable chromogen. The dyeability of synthesized dye for cotton fabrics was excellent and the dyed fabrics showed good level of lightfastness, resistance to washing and rubbing. The antibiotic tests revealed that the dyed cotton fabrics with the synthesized dye had very good antibiotic properties.

• 한국염색가공학회지
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• 제30권3호
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• pp.208-215
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• 2018

The objective was to investigate the efficacy of Metasequoia(Metasequoia glyptostroboides) cone colorants as a new functional dye for wool fiber. Effects of dyeing conditions and mordanting on dye uptake, color change, and colorfastness were investigated for wool fiber. Compared with cotton and silk fibers, wool fiber showed better affinity for the Metasequoia cone colorants. Fe and Cu mordants improved dye uptake, and mordanting did not change the color of dyed fabric with YR Munsell color. Colorfastness to rubbing and washing was as good as grade 4, whereas lightfastness of the dyed fabrics was above grade 3. Antimicrobial activity of the colorants was very high 99.3% of reduction rate toward S. aureus. It was confirmed that Metasequoia cone colorants can be utilized as a new functional natural dye for wool fiber. In addition, considering its high antimicrobial functionality it could be applied to cosmetics and food.

• 한국염색가공학회지
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• 제32권1호
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• pp.1-8
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• 2020

The objective was to study the efficiency of Houttuynia cordata extract colorants as eco-friendly and functional dye for wool fabrics. Effects of dyeing conditions and mordanting on dye uptake, color change, and colorfastness were investigated. Also, antimicrobial activity and deodorization performance were evaluated. The Houttuynia cordata colorants showed good affinity to wool fabrics and produced YR Munsell color. The optimum condition of dyeing was 2.0% of colorants concentration(o.w.b.) at 100℃ for 60 minutes under pH 5.3. Regardless of the mordant type and mordanting method, mordants improved dye uptake and the increase in dye uptake by Fe mordant was higher than that of Al mordant. Al post-mordanting and Fe mordanting changed the color of dyed fabrics with Y Munsell color. The colorfastness of un-mordanted and Al post-mordanted fabrics were excellent above grade 4. Bacteria reduction rate(Staphylococcus aureus) of wool fabrics dyed with Houttuynia cordata colorants was excellent at 98.2%. Also, the deodorization was good at 81%. The results show Houttuynia cordata colorants can be used as a functional natural dye for wool fabrics.

• 한국염색가공학회:학술대회논문집
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• 한국염색가공학회 2008년도 제39차 학술발표회
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• pp.15-16
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• 2008

A mixed bi-functional reactive dye has been applied to the cotton and the hemp, their dyeing and fastness were properties compared. Hemp exhibited better dyeability than cotton and this result was explained by the differences in the supramolecular structure of these two fibers.