• Journal of Electrochemical Science and Technology
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• v.3 no.1
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• pp.44-49
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• 2012

Electrochemical and photochemical techniques have been proved to be effective for the removal of organic pollutants in textile wastewater. The present study deals with degradation of synthetic textile effluents containing reactive dyes and assisting chemicals, using electro oxidation and photo catalytic treatment. The influence of various operating parameters such as dye concentration, current density, supporting electrolyte concentration and lamp intensity on TOC removal has been determined. From the present investigation it has been observed that nearly 70% of TOC removal has been recorded for electrooxidation treatment with current density 5 mA/$dm^2$, supporting electrolyte concentration of 3 g/L and in photocatalytic treatment with 250 V as optimum lamp intensity nearly 67% of TOC removal was observed. The result indicates that electro oxidation treatment is more efficient than photocatalytic treatment for dye degradation.

• Carbon letters
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• v.22
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• pp.1-13
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• 2017

Porous materials play a vital role in science and technology. The ability to control their pore structures at the atomic, molecular, and nanometer scales enable interactions with atoms, ions and molecules to occur throughout the bulk of the material, for practical applications. Three-dimensional (3D) porous carbon-based materials (e.g., graphene aerogels/hydrogels, sponges and foams) made of graphene or graphene oxide-based networks have attracted considerable attention because they offer low density, high porosity, large surface area, excellent electrical conductivity and stable mechanical properties. Water pollution and associated environmental issues have become a hot topic in recent years. Rapid industrialization has led to a massive increase in the amount of wastewater that industries discharge into the environment. Water pollution is caused by oil spills, heavy metals, dyes, and organic compounds released by industry, as well as via unpredictable accidents. In addition, water pollution is also caused by radionuclides released by nuclear disasters or leakage. This review presents an overview of the state-of-the-art synthesis methodologies of 3D porous graphene materials and highlights their synthesis for environmental applications. The various synthetic methods used to prepare these 3D materials are discussed, particularly template-free self-assembly methods, and template-directed methods. Some key results are summarized, where 3D graphene materials have been used for the adsorption of dyes, heavy metals, and radioactive materials from polluted environments.

• Textile Coloration and Finishing
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• v.20 no.2
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• pp.53-58
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• 2008

New dyeable PP fiber and several products from it has been developed through dispersing polyester copolymer into PP resin by a Korean synthetic fiber manufacturer and its colleagues. The dyeing properties of PET/dyeable PP double knit fabric were examined with three different types of disperse dye in this study. It was found that the disperse dye, exhausted on dyeable PP at early stage of dyeing, migrated to PET at elevated dyeing temperature when two fibers were dyed in the same dye bath. The ratios of dye distribution between two substrates dyed at $120^{\circ}C$ and $130^{\circ}C$ showed no difference. S type disperse dyes showed good build-up properties and acceptable color fastness while high light fastness type exhibited the lowest amounts of exhaustion but excellent color fastness. It might be concluded that the most appropriate dye for PET/dyeable PP double knit fabric was S type, and that some color difference between PET side and dyeable PP side was unvoidable.

• Journal of Microbiology and Biotechnology
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• v.12 no.4
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• pp.544-552
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• 2002

Several microorganisms from rat and human feces and lumen fluid of cows were screened for their ability to decolorize the synthetic dyes. Consequently, a novel dye-degrading strain AB&J was isolated. Taxonomic identification including 165 rDNA sequencing and phylogenetic analysis indicated that the isolate had 99.9% homology in its 165 rDNA base sequence with Clostridium perfringens. After 27 h Incubation with the strain, brilliant blue R, bromophenol blue, crystal violet, malachite green, methyl green, and methyl orange were decolorized by about 69.3%, 97.7%, 96.3%, 97.9%, 75.1%, and 97.2%, respectively. The triphenlmethane dye, bromophenol blue, was decolorized extensively by growing Clostridium perfringens AB&J cells in liquid cultures under anaerobic condition, although their growth was strongly inhibited in the initial stage of incubation. This group of dyes is toxic, depending on the concentration used. The dye was significantly decolorized at a relatively lower concentration of below 50 $\mu g \;ml^{-1}$, however, the growth of the cells was mostly suppressed at a dye concentration of 100 $\mu g \;ml^{-1}$. The decolorization activity in cell-free extracts was much higher in cytoplasm than in periplasm and cytoplasmic membrane. Therefore, the enzyme related uptake of bromophenol blue seemed to be localized in cytoplasm. The optimal pH and temperature of bromophenol blue uptake fur decolorization activities were 7.0 and 4$0^{\circ}C$, respectively.

• Journal of Microbiology and Biotechnology
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• v.27 no.6
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• pp.1120-1127
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• 2017

Marasmius scorodonius secretes an extracellular laccase in potato dextrose broth, and this enzyme was purified up to 206-fold using $(NH_4)_2SO_4$ precipitation and a Hi-trap Q Sepharose column. The molecular mass of the purified laccase was estimated to be ~67 kDa by SDS-PAGE. The UV/vis spectrum of the enzyme was nontypical for laccases, and metal content analysis revealed that the enzyme contains 1 mole of Fe and Zn and 2 moles of Cu per mole of protein. The optimal pH for the enzymatic activity was 3.4, 4.0, and 4.6 with 2,2'-azino-bis(3-ethylbenzothazoline-6-sulfonate) (ABTS), guaiacol, and 2,6-dimethoxy phenol as the substrate, respectively. The optimal temperature of the enzyme was $75^{\circ}C$ with ABTS as the substrate. The enzyme was stable in the presence of some metal ions such as $Ca^{2+}$, $Cu^{2+}$, $Ni^{2+}$, $Mg^{2+}$, $Mn^{2+}$, $Ba^{2+}$, $Co^{2+}$, and $Zn^{2+}$ at a low concentration (1 mM), whereas $Fe^{2+}$ completely inhibited the enzymatic activity. The enzymatic reaction was strongly inhibited by metal chelators and thiol compounds except for EDTA. This enzyme directly decolorized Congo red, Malachite green, Crystal violet, and Methylene green dyes at various decolorization rates of 63-90%. In the presence of 1-hydroxybenzotriazole as a redox mediator, the decolorization of Reactive orange 16 and Remazol brilliant blue R was also achieved.

• Tribology and Lubricants
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• v.32 no.5
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• pp.141-146
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• 2016

The diketopyrrolopyrrole (DPP) pigment is a bicyclic 8-π-electron system containing two lactam units. Typical DPP derivative pigments have melting points of over 350°C and very low solubility in most solvents, and show absorption in the visible region with a molar extinction coefficient of 33,000 dm²mol⁻¹ and strong photoluminescence with maxima in the range 500–600 nm. X-ray structure analyses of DPP show that the whole molecule is almost in one plane. The phenyl rings are twisted out of the heterocyclic plane and the intermolecular hydrogen bonding between neighboring lactam NH and carbonyl units influences the structure of the DPP pigment in the solid state. In this study, mono-N-alkylation and mono-N-arylation were undertaken for Pigment Red 264 or Pigment Orange 73 with alkyl halide and aryl halide, respectively, in the presence of sodium tert-butoxide as a base catalyst to improve the solubility of DPP pigments and their application as CO₂ indicators. The synthetic yield was in the range 11–88%. The indicator dyes are highly soluble in organic solvents and shows pH-dependent absorption (λ_max 501 and 572 nm for the protonated and deprotonated forms, respectively) and emission (λ_max 524 and 605 nm for the protonated and deprotonated forms, respectively) spectra. The mono-N-alkylated and mono-N-arylated DPP pigment was identified by ¹H-NMR (¹H-Nuclear Magnetic Resonance Spectrometer), FT-IR (Fourier Transform Infrared Spectroscopy), and MS (Mass Spectrometry). According to the results of color and hue properties obtained by a color matching analyzer, the synthesized DPP pigment material can be used as a CO₂ indicator.

• Biomolecules & Therapeutics
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• v.26 no.5
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• pp.481-486
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• 2018

Cosmetics are primarily applied to the skin; therefore, the association of cosmetic dyes with skin diseases or inflammation is a topic of great interest. Thymic stromal lymphopoietin (TSLP) is an interleukin 7-like cytokine that activates dendritic cells to promote Th2 inflammatory immune responses. TSLP is highly expressed in keratinocytes under inflammatory conditions, which suggests that it may play a critical role in the development of skin diseases, such as atopic dermatitis. Therefore, we investigated whether cosmetic dyes influenced the production of TSLP by keratinocytes. Phloxine O, also known as D&C Red No.27, is one of the most common red synthetic pigments and is widely used in colored cosmetics. Our results showed that Phloxine O downregulated phorbol 12-myristate 13-acetate-induced production of TSLP in a murine keratinocyte cell line (PAM212). Phloxine O also suppressed TSLP expression in KCMH-1 cells, which are mouse keratinocytes that constitutively produce high levels of TSLP. To investigate the in vivo effects of Phloxine O, we induced TSLP expression in mouse ear skin by topically applying MC903, a vitamin D3 analogue that is a well-known inducer of atopic dermatitis-like symptoms. Topical application of Phloxine O prevented MC903-induced TSLP production in mouse ear skin, attenuated the acute dermatitis-like symptoms and decreased serum IgE and histamine levels in mice. Suppression of TSLP expression by Phloxine O correlated with reduced expression of OX40 ligand and Th2 cytokines in mouse ear skin. Our results showed that Phloxine O may be beneficial to prevent dermatitis by suppressing the expression of TSLP and Th2 cytokines in skin.

• Journal of Korean Society on Water Environment
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• v.24 no.5
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• pp.537-542
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• 2008

Textile industry has been recognized as an important pollution source due to its consumption of large volumes of water and chemicals. Textile wastewater contains very diverse chemicals in types and composition, among them the presence of dyes is highly visible and undesirable. In spite of these problems, there has not been a proper control for the wastewater because many dyes are difficult to be degraded or decolorized due to their complex structure and synthetic characteristics. This study has been progressed to evaluate more easily the potential decolorization of advanced treatment processes. It has been surveyed with the Y textile complex wastewater treatment plant, the raw wastewater has appeared very difficult biodegradability by 4.7 of $CODcr/BOD_5$ and 1,158.9 degree of color. In view of CODcr fractions, biodegradable COD portion was 46.4%, colloidal COD and real soluble COD was 45.3% and 31.5% each others. From research on unit processes, the degradable coefficient (k) became from 0.065 to $0.125d^{-1}$ by the processes, the decolorization appeared best efficiency by 30.1% (458.4 degree) in pre-ozone process. On the effluent from the biological process, the filterable CODcr became 129.3 mg/L, the biodegradable portion appeared 64.7% (83.6 mg/L), and the fixed dissolved solid (FDS), non-reactivity (NR), appeared very heavy portion by 80.5% (1,659.0 mg/L).

• Fashion & Textile Research Journal
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• v.20 no.6
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• pp.752-758
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• 2018

Due to environmental pollution and human hazards of some synthetic dyes, the global fashion companies are increasingly interested in eco-friendly products, especially natural dye. For the globalization of natural dyeing industry based on this concern, however, there are some deficiencies of standardization, specification, and conformity assessment on natural dyestuffs as well as natural dyeing process. These obstacles should be not only studied but also defined for a commercial transaction. Accordingly, a study for conformity assessment on commercialized natural dyestuffs (red) was conducted by HPLC analysis in this study. As the results of HPLC analysis, alizarin and purpurin, representative index ingredients, were detected in most of the samples, but the index ingredient content in each sample was different. In addition, some samples showed the variety of peaks including the index ingredients and others. It was inferred that the representative index ingredients could be used on the traceability of natural sourced dyestuffs. These results are related to the index ingredient consistency, standardization, and reproducibility of natural dyed products including such as yarns, fabrics, garments, and so on. Therefore, the present study was demonstrated that in order to determine the conformity assessment system for the satisfaction of all stakeholders, the offering of information on the origin, manufacturing process, and index ingredient content of natural dyes should be prioritized.

• KSBB Journal
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• v.22 no.5
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• pp.271-277
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• 2007

Natural pigments have many applications like colouring agent, pigments, food additives, and antiseptics. At present, instead of synthetic pigments that have contributed to the development of industry, many kinds of natural pigments have been developed. The constituents of gardenia fruits, Gardenia jasminoides ELLIS, are traditionally known as herb medicine and natural dyes/pigments due to the customer is needs. The fruits produce yellow carotenoid pigments and iridoid compounds. The two main components in the yellow pigments are called crocin and crocetin. The extraction mode of yellow pigment from Gardenia is depended upon the extraction time, temperature, and volume of solvent. Red pigments or blue pigments formed from geniposide and amino acids have been reported a lot. Geniposide, the principal iridoid glucoside contained in gardenia fruit, was hydrolyzed to genipinic acid or genipin as a precursor for the pigment by enzymatic or chemical reaction. These red or blue pigments prepared with materials hydrolyzed of geniposide and amino acid and had properties governed by the electrostatic character of the amino acid. The pigments showed good stability to heat and pH but were gradually bleached by light while the other natural pigments are unstable in light, heat, acid, and base solution. The safety of the pigments was considered to be of little virulences in comparison to synthetic pigments.