Photo orientation of azo dye molecules in glassy o-terphenyl

A new developed sequencing batch process for the purification of residual water containing concentrated azo dye was investigated. Within a treatment cycle the biological anoxic decolorization, followed by an aerobic mineralization of organic metabolites in combination with the biodegradability-achieving partial oxidation with ozone are carried out sequentially. The split flow can be destructively purified to 90% with respect to the parameter DOC. It was decolorized to an extent of 98% and the toxicity measured by the bioluminescence test decreased up to 99%. With an unspecific facultative anaerobic bacterial mixed culture anoxic decolorization of the residual liquor (20 gdye/L) without addition of an external auxiliary substrate was observed. In the first phase of the treatment cycle, the azo dye-molecules are cleft at the azo bond by biochemical reduction which leads to the corresponding sulfonated aromatic amines. In the following aerobic phase the cleft products were mineralized by the same microorganisms in the same reactor. Because of the recalcitrant and respectively toxic character of a part of the remaining metabolites, further aerobic mineralization was initialized by partial oxidation with ozone. The recursive ozonization in a recircled stream with biological post-treatment of the transformed substances led to an increased reaction selectivity and lower consumption of ozone. The results have shown that the chosen sequencing batch reactor with the ozonization bypass is suitable for an effective treatment of high concentrated dyehouse liquors.

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Photocatalytic activity of reticulated ZnO porous ceramics in degradation of azo dye molecules

Journal of the European Ceramic Society ◽

10.1016/j.jeurceramsoc.2015.03.042 ◽

2015 ◽

Vol 35 (10) ◽

pp. 2845-2853 ◽

Cited By ~ 17

Author(s):

Alphan Kocakuşakoğlu ◽

Memnune Dağlar ◽

Mehmet Konyar ◽

H. Cengiz Yatmaz ◽

Koray Öztürk

Keyword(s):

Photocatalytic Activity ◽

Azo Dye ◽

Porous Ceramics ◽

Dye Molecules ◽

Degradation Of Azo Dye

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Orientation of azo-dye molecules and optical nonlinearity in azo-dye-doped polymeric waveguides

10.1117/12.475925 ◽

2002 ◽

Author(s):

A. V. Tomov ◽

Alexander V. Khomchenko ◽

E. P. Kalutskaya

Keyword(s):

Azo Dye ◽

Optical Nonlinearity ◽

Dye Molecules

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Patterned Photoalignment in Thin Films: Physics and Applications

Crystals ◽

10.3390/cryst11020084 ◽

2021 ◽

Vol 11 (2) ◽

pp. 84

Author(s):

Vladimir Chigrinov ◽

Aleksey Kudreyko ◽

Qi Guo

Keyword(s):

Liquid Crystals ◽

Azo Dye ◽

Rotational Diffusion ◽

Incident Light ◽

Polarized Light ◽

Photonic Devices ◽

Dye Molecules ◽

Ferroelectric Liquid Crystals ◽

Dependent Change ◽

Alignment Process

Photoalignment of liquid crystals by using azo dye molecules is a commonly proposed alternative to traditional rubbing alignment methods. Photoalignment mechanism can be well described in terms of rotational diffusion of azo dye molecules exposed by ultraviolet polarized light. A specific feature of the irradiated light is the intensity dependent change of azimuthal anchoring of liquid crystals. While there are various mechanisms of azo dye photoalignment, photo-reorientation occurs when dye molecules orient themselves perpendicular to the polarization of incident light. In this review, we describe both recent achievements in applications of photoaligned liquid crystal cells and its simulation. A variety of display and photonic devices with azo dye aligned nematic and ferroelectric liquid crystals are presented: q-plates, optically rewritable flexible e-paper (monochromatic and color), and Dammann gratings. Some theoretical aspects of the alignment process and display simulation are also considered.

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Photoisomerization and photoorientation of brilliant yellow in the thin film state

Doklady of the National Academy of Sciences of Belarus ◽

10.29235/1561-8323-2019-63-2-169-174 ◽

2019 ◽

Vol 63 (2) ◽

pp. 169-174

Author(s):

S. N. Lemiashonak ◽

Zh. D. Chaplanova ◽

V. E. Agabekov ◽

N. A. Ivanova ◽

I. N. Kukhta

Keyword(s):

Thin Film ◽

Azo Dye ◽

Order Reaction ◽

Dye Molecules ◽

Brilliant Yellow ◽

Reaction Equation ◽

First Order ◽

Ultra High Pressure ◽

Linearly Polarized ◽

Film State

The features of photoisomerization and photoorientation of azo dye brilliant yellow (BY) in the thin film state are studied. The trans-cis-isomerization of the dye molecules is established to proceed upon irradiation of the films based on BY with a full light of an ultra-high pressure lamp DRT-1000 (UV / VID light), this reaction is described by the first-order reaction equation. Under the action of linearly polarized blue light (λ = 457 nm), an optical anisotropy arises in films of BY. Optically anisotropic films of BY with a high dichroic ratio (>10) are shown to be formed using N-methylpyrrolidone and N, N-dimethylformamide as solvents and cellulose acetate as the polymer matrix.

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SORPTION OF RED FOOD COLORING POLYMERS WITH MOLECULAR IMPRINTS

IZVESTIYA VYSSHIKH UCHEBNYKH ZAVEDENIY KHIMIYA KHIMICHESKAYA TEKHNOLOGIYA ◽

10.6060/tcct.2017607.5595 ◽

2017 ◽

Vol 60 (7) ◽

pp. 42 ◽

Cited By ~ 1

Author(s):

Alexander N. Zyablov ◽

Svetlana A. Khalzova ◽

Vladimir F. Selemenev

Keyword(s):

Azo Dye ◽

Polymeric Materials ◽

Distribution Coefficients ◽

Hydroxyl Group ◽

Synthetic Dyes ◽

Dye Molecules ◽

Maximum Sorption Capacity ◽

Sorption Ability ◽

Molecular Imprint ◽

Dye Molecule

Polymers with molecular imprints are used as modifiers of the surface of piezoelectric sensors, so it is necessary to study their sorption properties. Isotherms of sorption of synthetic dyes with polymers with molecular imprint and their comparison polymers are obtained. The type of sorption isotherm is characteristic for polymeric materials with micro- and mesopores. The maximum sorption capacity of polymers in relation to dyes is determined, the areas of the projection of the dye molecules on the surface of the sorbent are estimated. With the sorption of multiply charged anionic dye particles, the surface of the sorbent acquires a partial negative charge, which makes it difficult to sorbate as the surface concentration of the sorbate increases. The efficiency of sorption of azo dyes by polymers with molecular imprint from aqueous solutions depends on the amount of ionized sulfo groups in the azo dye molecule, their location in the benzene ring, the symmetry of the dye molecule. Sorption of azo dye by polymers with molecular prints is mainly due to the formation of hydrogen bonds between the sulphonic group of the dye and the hydroxyl group of the sorbent. The area of the projections of molecules on the surface of the modified polymer for all the dyes does not exceed the calculated values of the areas of the molecules, which indicates a loose filling of the sorbent surface and it is probable that the orientation of the dye molecules in the adsorption layer is close to perpendicular to the surface of the sorbent. The values of extraction rates and distribution coefficients are determined, the imprinting factor is calculated. The highest imprinting factor was obtained for the azo dye Ponso 4R. It has been established that polymers with molecular imprinting based on polyimide have better sorption ability with respect to target molecules than their comparison polymers.Forcitation:Zyablov A.N., Khalzova S.A., Selemenev V.F. Sorption of red food coloring polymers with molecular imprints. Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol. 2017. V. 60. N 7. P. 42-47.

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