Degradation of azo dyes by environmental microorganisms and helminths

Energy Technology Data Exchange (ETDEWEB)

Kingthom Chung; Stevens, S.E. Jr. (Memphis State Univ., TN (United States). Dept. of Biology)

1993-11-01

The degradation of azo dyes by environmental microorganisms, fungi, and helminths is reviewed. Azo dyes are used in a wide variety of products and can be found in the effluent of most sewage treatment facilities. Substantial quantities of these dyes have been deposited in the environment, particularly in streams and rivers. Azo dyes were shown to affect microbial activities and microbial population sizes in the sediments and in the water columns of aquatic habitats. Only a few aerobic bacteria have been found to reduce azo dyes under aerobic conditions, and little is known about the process. A substantial number of anaerobic bacteria capable of azo dye reduction have been reported. The enzyme responsible for azo dye reduction has been partially purified, and characterization of the enzyme is proceeding. The nematode Ascaris lumbricoides and the cestode Moniezia expanza have been reported to reduce azo dyes anaerobically. Recently the fungus Phanerochaete chrysoporium was reported to mineralize azo dyes via a peroxidation-mediated pathway. A possible degradation pathway for the mineralization of azo dye is proposed and future research needs are discussed.

The structural and electro-optical characteristics of AZO/Cr:Cu/AZO transparent conductive film

International Nuclear Information System (INIS)

Lin, Tien-Chai; Huang, Wen-Chang; Tsai, Fu-Chun

2015-01-01

A novel triple-layered transparent conductive film, AZO/Cr:Cu/AZO (ACCA), was presented in the paper. The structural and electro-optical properties of the ACCA film were discussed. The thickness of the middle metal layer was constant and those of the AZO layers were varied. The ACCA film shows an obvious ZnO (002) c-axis preferential growth. No diffraction peaks related to Cr and Cu were observed through x-ray diffraction analysis. The middle Cr:Cu layer showed a thickness of 8.16 nm with a continuous and amorphous structure by the observation of a high-resolution transmission electron microscopy (HR-TEM). For the electro-optical characteristic, a best figure of merit (FOM) value of 3.54 × 10 −3 Ω −1 with a corresponding transmittance of 85% was obtained at the thickness of 116 nm of ACCA film. The high FOM value of the film is due to the improvement of conductivity and small sacrifices of transparency. - Highlights: • A novel triple-layered transparent conductive film, AZO/Cr:Cu/AZO is developed. • Chromium is added to copper to reduce the oxidation–reduction reaction. • The film has a FOM of 3.54 × 10 −3 Ω −1 with a corresponding transmittance of 85%. • The Cr:Cu layer shows a continuous and amorphous structure

The structural and electro-optical characteristics of AZO/Cr:Cu/AZO transparent conductive film

Energy Technology Data Exchange (ETDEWEB)

Lin, Tien-Chai [Department of Electrical Engineering, Kun Shan University, No. 195, Kun-Da Road, Yung-Kang Dist., Tainan 71003, Taiwan, ROC (China); Huang, Wen-Chang, E-mail: wchuang@mail.ksu.edu.tw [Department of Electro-Optical Engineering, Kun Shan University, No. 195, Kun-Da Road, Yung-Kang Dist., Tainan 71003, Taiwan, ROC (China); Tsai, Fu-Chun [Department of Electro-Optical Engineering, Kun Shan University, No. 195, Kun-Da Road, Yung-Kang Dist., Tainan 71003, Taiwan, ROC (China)

2015-08-31

A novel triple-layered transparent conductive film, AZO/Cr:Cu/AZO (ACCA), was presented in the paper. The structural and electro-optical properties of the ACCA film were discussed. The thickness of the middle metal layer was constant and those of the AZO layers were varied. The ACCA film shows an obvious ZnO (002) c-axis preferential growth. No diffraction peaks related to Cr and Cu were observed through x-ray diffraction analysis. The middle Cr:Cu layer showed a thickness of 8.16 nm with a continuous and amorphous structure by the observation of a high-resolution transmission electron microscopy (HR-TEM). For the electro-optical characteristic, a best figure of merit (FOM) value of 3.54 × 10{sup −3} Ω{sup −1} with a corresponding transmittance of 85% was obtained at the thickness of 116 nm of ACCA film. The high FOM value of the film is due to the improvement of conductivity and small sacrifices of transparency. - Highlights: • A novel triple-layered transparent conductive film, AZO/Cr:Cu/AZO is developed. • Chromium is added to copper to reduce the oxidation–reduction reaction. • The film has a FOM of 3.54 × 10{sup −3} Ω{sup −1} with a corresponding transmittance of 85%. • The Cr:Cu layer shows a continuous and amorphous structure.

Electrical circuit model of ITO/AZO/Ge photodetector.

Science.gov (United States)

Patel, Malkeshkumar; Kim, Joondong

2017-10-01

In this data article, ITO/AZO/Ge photodetector was investigated for electrical circuit model. Due to the double (ITO and AZO) transparent metal-oxide films (DOI:10.1016/j.mssp.2016.03.007) (Yun et al., 2016) [1], the Ge heterojunction device has a better interface quality due to the AZO layer with a low electrical resistance due to the ITO layer (Yun et al., 2015) [2]. The electrical and interfacial benefitted ITO/AZO/Ge heterojunction shows the quality Schottky junction. In order to investigate the device, the ITO/AZO/Ge heterojunction was analyzed by R-C circuit model using the impedance spectroscopy.

Trans-Planckian wimpzillas

CERN Document Server

Kolb, E W; Tkachev, I I

2007-01-01

Two previously proposed conjectures--gravitational trans-Planckian particle creation in the expanding universe, and the existence of ultra-heavy stable particles with masses up to the Planck scale (wimpzillas)--are combined in a proposal for trans-Planckian particle creation of wimpzillas. It is shown that the trans-Planckian particle creation parameter should be rather small to avoid overproduction of such particles. This ensures that wimpzillas are mainly created at the end of primordial inflation. Conditions under which trans-Planckian wimpzillas can constitute the present dark matter are determined.

Inhibition of nuclear T3 binding by fatty acids: dependence on chain length, unsaturated bonds, cis-trans configuration and esterification

NARCIS (Netherlands)

Wiersinga, W. M.; Platvoet-ter Schiphorst, M.

1990-01-01

1. Fatty acids have the capacity for inhibition of nuclear T3 binding (INB). The present studies were undertaken to describe the INB-activity of fatty acids as a function of chain length, unsaturated bonds, cis-trans configuration, and esterification. 2. Isolated rat liver nuclei were incubated with

Electrical circuit model of ITO/AZO/Ge photodetector

Directory of Open Access Journals (Sweden)

Malkeshkumar Patel

2017-10-01

Full Text Available In this data article, ITO/AZO/Ge photodetector was investigated for electrical circuit model. Due to the double (ITO and AZO transparent metal-oxide films (DOI:10.1016/j.mssp.2016.03.007 (Yun et al., 2016 [1], the Ge heterojunction device has a better interface quality due to the AZO layer with a low electrical resistance due to the ITO layer (Yun et al., 2015 [2]. The electrical and interfacial benefitted ITO/AZO/Ge heterojunction shows the quality Schottky junction. In order to investigate the device, the ITO/AZO/Ge heterojunction was analyzed by R–C circuit model using the impedance spectroscopy.

Liposome fusion and lipid exchange on ultraviolet irradiation of liposomes containing a photochromic phospholipid

International Nuclear Information System (INIS)

Morgan, C.G.; Sandhu, S.S.; Mitchell, A.C.

1995-01-01

A photochromic phospholipid, 1,2-bis[4-n-butylphenylazo)phenylbutyroyl]phosphatidylcholine (Bis-Azo PC) has been incorporated inot liposomes of gel- and liquid-crystalline-phase phospholipids. Liposomes of gel-phase phospholipid are stable in the presence of the trans photostationary state Bis-Az0 PC and can encapsulate fluorescent marker dye. On photoisomerization to the cis photostationary state, trapped marker is rapidly released. Liposomes containing Bis-Azo PC can rapidly fuse together after UV isomerization, this process continuing in the dark. Exposure to white light causes reversion of Bis-Azo PC to the trans form and halts dye leakage and vesicle fusion. Both unilamellar and multilamellar liposomes are able to fuse together on UV exposure. On UV photolysis, liposomes containing Bis-Azo PC do not fuse with a large excess of unlabeled liposomes, but transfer of Bis-Azo PC can be demonstrated spectrophotometrically. Vesicles of pure gel-phase lipid containing trapped marker dye but initially no Bis-Azo PC become leaky as a result of this lipid transfer. Liposomes composed of liquid-crystalline-phase phosphatidylcholine-containing Bis-Azo PC neither leak trapped marker nor fuse together on photolysis, nor do liquid-crystalline-phase liposomes, fuse with gel-phase liposomes under these conditions. (Author)

Evidence for significantly enhancing reduction of Azo dyes in Escherichia coli by expressed cytoplasmic Azoreductase (AzoA) of Enterococcus faecalis.

Science.gov (United States)

Feng, J; Heinze, T M; Xu, H; Cerniglia, C E; Chen, H

2010-05-01

Although cytoplasmic azoreductases have been purified and characterized from various bacteria, little evidence demonstrating that these azoreductases are directly involved in azo dye reduction in vivo is known. In order to evaluate the contribution of the enzyme to azo dye reduction in vivo, experiments were conducted to determine the effect of a recombinant cytoplasmic azoreductase (AzoA) from Enterococcus faecalis expressed in Escherichia coli on the rate of metabolism of Methyl Red, Ponceau BS and Orange II. The intact cells that contained IPTG induced AzoA had a higher rate of dye reduction with increases of 2 (Methyl Red), 4 (Ponceau BS) and 2.6 (Orange II)-fold compared to noninduced cells, respectively. Metabolites of Methyl Red isolated from induced cultures were identified as N,N-dimethyl-p-phenylenediamine and 2-aminobenzoic acid through liquid chromatography electrospray ionization tandem mass spectrometry (LC/ESI-MS/MS) analyses. In conclusion, our data demonstrate that AzoA from Ent. faecalis is capable of increasing the reduction of azo dyes in intact E. coli cells and that cytoplasmic azoreductase is involved in bacterial dye degradation in vivo.

The Hydractinia echinata Test-System. III: Structure-Toxicity Relationship Study of Some Azo-, Azo-Anilide, and Diazonium Salt Derivatives

Directory of Open Access Journals (Sweden)

Sergiu Adrian Chicu

2014-07-01

Full Text Available Structure-toxicity relationships for a series of 75 azo and azo-anilide dyes and five diazonium salts were developed using Hydractinia echinata (H. echinata as model species. In addition, based on these relationships, predictions for 58 other azo-dyes were made. The experimental results showed that the measured effectiveness Mlog(1/MRC50 does not depend on the number of azo groups or the ones corresponding to metobolites, but it is influenced by the number of anilide groups, as well as by the substituents’ positions within molecules. The conformational analysis pointed out the intramolecular hydrogen bonds, especially the simple tautomerization of quinoidic (STOH or aminoidic (STNH2 type. The effectiveness is strongly influenced by the “push-pull” electronic effect, specific to two hydroxy or amino groups separated by an azo moiety (double alternate tautomery, (DAT, to the –COOH or –SO3H groups which are located in ortho or para position with respect to the azo group. The levels of the lipophylic/hydrophilic, electronic and steric equilibriums, pointed out by the Mlog(1/MRC50 values, enabled the calculation of their average values Clog(1/MRC50 (“Köln model”, characteristic to one derivative class (class isotoxicity. The azo group reduction and the hydrolysis of the amido/peptidic group are two concurrent enzymatic reactions, which occur with different reaction rates and mechanisms. The products of the partial biodegradation are aromatic amines. No additive or synergic effects are noticed among them.

The mechanism and kinetics of the electrochemical cleavage of azo bond of 2-hydroxy-5-sulfophenyl-azo-benzoic acids

International Nuclear Information System (INIS)

Mandic, Zoran; Nigovic, Biljana; Simunic, Branimir

2004-01-01

The electrochemical reduction of 2-hydroxy-5-[(4-sulfophenyl)azo]benzoic acid, 2-hydroxy-5-[(3-sulfophenyl)azo]benzoic acid, 2-hydroxy-5-[(2-sulfophenyl)azo]benzoic acid and 2-hydroxy-5-azo-benzoic acid has been carried out in aqueous solutions at glassy carbon electrode using cyclic voltammetry and chronoamperometry. The position of sulfo substituent relative to azo bridge as well as pH of the solution have significant impact on the electrochemical behavior of these compounds. It has been proposed that these compounds are reduced predominantly as hydrazone tautomers resulting in corresponding hydrazo compounds. The overall electrochemical reduction follows DISP2 mechanism, ultimately leading to the 5-amino salicylic acid and sulfanilic acid. The rate determining step is the homogenous redox reaction between intermediate hydrazo compound and 5-amino salicylic acid quinoneimine. The mechanism is proposed in which activated complex of 5-amino salicylic acid quinoneimine and intermediate hydrazo compound is formed with the simultaneous loss of one proton

Aerobic decolourization of two reactive azo dyes under varying ...

African Journals Online (AJOL)

STORAGESEVER

2010-02-01

Feb 1, 2010 ... Azo dyes generally resist aerobic microbial degra- dation, only organisms with specialized azo dye reducing enzymes were found to degrade azo dyes under fully aerobic ... textile mill, in sterile plastic bottles. Isolation of ...

Characterization of AZO and Ag based films prepared by RF magnetron sputtering

International Nuclear Information System (INIS)

Miao, Dagang; Jiang, Shouxiang; Zhao, Hongmei; Shang, Songmin; Chen, Zhuoming

2014-01-01

Highlights: • Highly infrared reflective AZO and Ag based films were prepared. • Ag showed better crystallization on AZO film than on glass substrate. • Infrared reflection rate was inversely proportional to the film sheet resistance. • Film with infrared reflection of 97% in FIR region was acquired. - Abstract: Ag, AZO/Ag, Ag/AZO and AZO/Ag/AZO films were prepared on glass substrates by radio frequency (RF) magnetron sputtering technology. The prepared films were systematically investigated by X-ray Diffraction (XRD), Atomic Force Microscopy (AFM), UV–visible spectrophotometer, a four-point probe system and Fourier Transform Infrared Spectroscopy. The results indicated that Ag inner layer starts forming a continuous film at the thickness of 10 nm and Ag layer presents superior crystallization on AZO substrate than that on glass substrate. The continuous Ag inner layer film provided the highest average visible transmittance of 85.4% (AZO/Ag/AZO). The lowest sheet resistance of 3.21 Ω/sq and the highest infrared reflection rate of 97% in FIR region can be obtained on AZO/Ag (15 nm)/AZO film. The high infrared reflection property of the AZO/Ag/AZO coating makes it a promising candidate for solar control films

Comparison of carrier transport mechanism under UV/Vis illumination in an AZO photodetector and an AZO/p-Si heterojunction photodiode produced by spray pyrolysis

International Nuclear Information System (INIS)

Shasti, M.; Mortezaali, A.; Dariani, R. S.

2015-01-01

In this study, Aluminum doped Zinc Oxide (AZO) layer is deposited on p-type silicon (p-Si) by spray pyrolysis method to fabricate ultraviolet-visible (UV/Vis) photodetector as Al doping process can have positive effect on the photodetector performance. Morphology, crystalline structure, and Al concentration of AZO layer are investigated by SEM, XRD, and EDX. The goal of this study is to analyze the mechanism of carrier transport by means of current-voltage characteristics under UV/Vis illumination in two cases: (a) electrodes connected to the surface of AZO layer and (b) electrodes connected to cross section of heterojunction (AZO/p-Si). Measurements indicate that the AZO/p-Si photodiode exhibits a higher photocurrent and lower photoresponse time under visible illumination with respect to AZO photodetector; while under UV illumination, the above result is inversed. Besides, the internal junction field of AZO/p-Si heterojunction plays an important role on this mechanism

Comparison of carrier transport mechanism under UV/Vis illumination in an AZO photodetector and an AZO/p-Si heterojunction photodiode produced by spray pyrolysis

Energy Technology Data Exchange (ETDEWEB)

Shasti, M.; Mortezaali, A., E-mail: mortezaali@alzahra.ac.ir; Dariani, R. S. [Department of Physics, Alzahra University, Tehran 1993893973 (Iran, Islamic Republic of)

2015-01-14

In this study, Aluminum doped Zinc Oxide (AZO) layer is deposited on p-type silicon (p-Si) by spray pyrolysis method to fabricate ultraviolet-visible (UV/Vis) photodetector as Al doping process can have positive effect on the photodetector performance. Morphology, crystalline structure, and Al concentration of AZO layer are investigated by SEM, XRD, and EDX. The goal of this study is to analyze the mechanism of carrier transport by means of current-voltage characteristics under UV/Vis illumination in two cases: (a) electrodes connected to the surface of AZO layer and (b) electrodes connected to cross section of heterojunction (AZO/p-Si). Measurements indicate that the AZO/p-Si photodiode exhibits a higher photocurrent and lower photoresponse time under visible illumination with respect to AZO photodetector; while under UV illumination, the above result is inversed. Besides, the internal junction field of AZO/p-Si heterojunction plays an important role on this mechanism.

An Improved Method for Removal of Azo Dye Orange II from Textile Effluent Using Albumin as Sorbent

Directory of Open Access Journals (Sweden)

Tadashi Ohashi

2012-11-01

Full Text Available Azo dyes are generally resistant to biodegradation due to their complex structures. Acid orange II is one of the most widely used dyes in the textile industry. The influence of bovine serum albumin (BSA in different concentrations, pH, and time of contact on Orange II was investigated using kinetics and adsorption-isotherm experiments. The results showed that the maximum colour removed from dye/albumin was 99.50% and that a stable dye-protein complex had been formed at pH 3.5 and in a proportion of 1:3 (v/v, respectively. The synthetic effluent did not show toxicity to the microcrustacean Artemia salina, and showed a CL50 equal to 97 µg/mL to azo dye orange II. Additionally, the methodology was effective in removing the maximum of orange II using BSA by adsorption at pH 3.5 which mainly attracted ions to the azo dye during the adsorption process. This suggests that this form of treatment is economical and easy to use which potentially could lead to bovine serum albumin being used as a sorbent for azo dyes.

Highly transparent conductive AZO/Zr50Cu50/AZO films in wide range of visible and near infrared wavelength grown by pulsed laser deposition

Directory of Open Access Journals (Sweden)

Jingyun Cheng

Full Text Available Novel AZO/Zr50Cu50/AZO tri-layer transparent conductive films with excellent transmittance in both visible and near infrared region were successfully prepared by pulsed laser deposition on glass substrates. The electrical and optical properties were investigated at various Zr50Cu50 thicknesses. As the AZO thickness was fixed at 50 nm and Zr50Cu50 thickness was varied between 1 and 18 nm, it was found that AZO (50 nm/Zr50Cu50/AZO (50 nm tri-layer films exhibited good conductivity and high transmittance in both visible and near infrared wavelength. Additionally, both the electrical and optical properties of AZO (50 nm/Zr50Cu50 (2 nm/AZO (50 nm tri-layer films were found to be sensitive to the growth temperature. In this work, the lowest sheet resistance (43 Ω/□ and relatively high transmittance (∼80% in the range of 400–2000 nm were achieved while the growth temperature was 350 °C. Furthermore, the AZO (50 nm/Zr50Cu50 (2 nm/AZO (50 nm thin film deposited at 350 °C exhibits the highest figure of merit of 1.42 × 10−3 Ω−1, indicating that the multilayer is promising for coated glasses and thin film solar cells. Keywords: Transparent conductive oxide, AZO, Zr50Cu50, Electrical and optical properties, Visible and near infrared transmittance

Modification of azo dyes by lactic acid bacteria.

Science.gov (United States)

Pérez-Díaz, I M; McFeeters, R F

2009-08-01

The ability of Lactobacillus casei and Lactobacillus paracasei to modify the azo dye, tartrazine, was recently documented as the result of the investigation on red coloured spoilage in acidified cucumbers. Fourteen other lactic acid bacteria (LAB) were screened for their capability to modify the food colouring tartrazine and other azo dyes of relevance for the textile industry. Most LAB modified tartrazine under anaerobic conditions, but not under aerobic conditions in modified chemically defined media. Microbial growth was not affected by the presence of the azo dyes in the culture medium. The product of the tartrazine modification by LAB was identified as a molecule 111 daltons larger than its precursor by liquid chromatography-mass spectrometry. This product had a purple colour under aerobic conditions and was colourless under anaerobic conditions. It absorbed light at 361 and 553 nm. LAB are capable of anabolizing azo dyes only under anaerobic conditions. IMPACT AND SIGNIFICANCE OF THE STUDY: Although micro-organisms capable of reducing the azo bond on multiple dyes have been known for decades, this is the first report of anabolism of azo dyes by food related micro-organisms, such as LAB.

Linearly and circularly polarized laser photoinduced molecular order in azo dye doped polymer films

Directory of Open Access Journals (Sweden)

Saad Bendaoud

2017-01-01

Full Text Available Photo-induced behavior of Azo Disperse one (AZD1 doped Poly(Methyl MethAcrylate (PMMA using both linear and circular polarized light is studied. The anisotropy is not erased by the circular polarization light. The circular polarization light combined with relatively long lifetime of the cis state in azo dye doped polymers activate all transverse directions of the angular hole burning through the spot in the film inducing anisotropy. Under circular polarized light, there is no orientation perpendicularly to the helex described by the rotating electric field vector, trans molecules reorients in the propagation direction of the pump beam. The polarization state of the probe beam after propagation through the pumped spot depends strongly on the angle of incidence of both pump and probe beams on the input face. In the case where circular polarized pump and probe beams are under the same angle of incidence, the probe beam “sees” anisotropic film as if it is isotropic. Results of this work shows the possibility to reorient azobenzene-type molecules in two orthogonal directions using alternately linearly and circularly polarized beams.

Integrated and sequential anaerobic/aerobic biodegradation of azo dyes

NARCIS (Netherlands)

Tan, N.G.C.

2001-01-01

Azo dyes constitute a major class of environmental pollutants accounting for 60 to 70% of all dyes and pigments used. These compounds are characterized by aromatic moieties linked together with azo groups (-N=N-). The release of azo dyes into the environment is a concern due to coloration

Preparation and Properties of Flexible AZO@C Nanofibers

Directory of Open Access Journals (Sweden)

MA Hui

2018-01-01

Full Text Available A new type of environmental-friendly flexible nanofibers of aluminum doped zinc oxide (AZO coated carbon (AZO@C was successfully prepared by using polyvinyl alcohol (PVA as raw materials. The as-spun PVA nanofibers were prepared via electrospinning and its water resistance was greatly improved after heat-treatment. Then, the PVA nanofibers with a layer of zinc aluminum hydroxide on the surface were synthesized by hydrothermal method. Thereafter, new AZO@C composite nanofibers was produced after sintering at 500℃ to the carbonization of PVA nanofibers and the dehydration of zinc aluminum hydroxide to form AZO nanoparticles. The structure and properties of the samples were characterized by Fourier-transform infrared spectrometer (FT-IR, thermal gravimetric analyzer (TGA and scanning electron microscope (SEM. The average diameter of the AZO@C nanofibers is (320±45nm. The photocatalytic property of the resultant composite fibers is demonstrated by degrading methyl orange under solar light.

Characteristics of indium-free GZO/Ag/GZO and AZO/Ag/AZO multilayer electrode grown by dual target DC sputtering at room temperature for low-cost organic photovoltaics

Energy Technology Data Exchange (ETDEWEB)

Park, Ho-Kyun; Kim, Han-Ki [Department of Display Materials Research Center, Materials Research Center for Information Displays (MRCID), Kyung Hee University, 1 Seocheon-dong, Youngin-si, Gyeonggi-do 446-701 (Korea); Kang, Jae-Wook [Department of Material Processing, Korea Institute of Materials Science(KIMS), 66 Sangnam-dong, Changwon-si, Gyeongnam 641-831 (Korea); Na, Seok-In; Kim, Don-Yu. [Heeger Center for Advanced Materials, Department of Materials Science and Engineering, Gwangju Institute of Science and Technology, 1 Oryoung-dong, Gwangju 500-712 (Korea)

2009-11-15

We compared the electrical, optical, structural and surface properties of indium-free Ga-doped ZnO (GZO)/Ag/GZO and Al-doped ZnO (AZO)/Ag/AZO multilayer electrodes deposited by dual target direct current sputtering at room temperature for low-cost organic photovoltaics. It was shown that the electrical and optical properties of the GZO/Ag/GZO and AZO/Ag/AZO multilayer electrodes could be improved by the insertion of an Ag layer with optimized thickness between oxide layers, due to its very low resistivity and surface plasmon effect. In addition, the Auger electron spectroscopy depth profile results for the GZO/Ag/GZO and AZO/Ag/AZO multilayer electrodes showed no interfacial reaction between the Ag layer and GZO or AZO layer, due to the low preparation temperature and the stability of the Ag layer. Moreover, the bulk heterojunction organic solar cell fabricated on the multilayer electrodes exhibited higher power conversion efficiency than the organic solar cells fabricated on the single GZO or AZO layer, due to much lower sheet resistance of the multilayer electrode. This indicates that indium-free GZO/Ag/GZO and AZO/Ag/AZO multilayer electrodes are a promising low-cost and low-temperature processing electrode scheme for low-cost organic photovoltaics. (author)

Dendritic azo compounds as a new type amorphous molecular material with quick photoinduced surface-relief-grating formation ability

Science.gov (United States)

He, Yaning; Gu, Xinyu; Guo, Miaocai; Wang, Xiaogong

2008-09-01

A series of dendritic azobenzene-containing compounds have been synthesized as a new type amorphous molecular material, which can show quick surface-relief-grating (SRG) formation ability upon light irradiation. For the synthesis, the dendritic precursor tris(2-(ethyl(phenyl)amino)ethyl)benzene-1,3,5-tricarboxylate and tris(3,5-bis(2-(ethyl(phenyl)amino)ethoxy)benzyl)benzene-1,3,5-tricarboxylate were prepared by esterification reactions between 1,3,5-benzenetricarbonyl chloride and N-ethyl- N-hydroxyethyl-aniline and 3,5-bis[2-( N-ethylanilino)ethoxy] benzylalcohol. The precursors were, respectively reacted with the diazonium salts of 4-nitroaniline, 4-aminobenzoic acid, and 4-aminobenzonitrile to introduce different types of donor-acceptor azo chromophores at the peripheral positions. The structure and properties of the dendritic azo compounds were characterized by the spectroscopic methods and thermal analysis. The surface-relief-grating (SRG) formation behavior of the dendritic azo compounds was studied by exposing the spin-coated thin films to an interference pattern of laser beams (532 nm) at modest intensity (100 mW/cm 2). The results show that the azo compounds can form stable amorphous glasses in a broad temperature range. The glass transition temperatures ( Tgs) depend on the backbone structures and the type of the peripheral azo chromophors. The type of the electron withdrawing groups in the p-positions of the terminal azobenzene units shows a significant influence on the SRG inscription rate. For the compounds containing the same type azo chromophores, the SRG inscription rate is also affected by the backbone structure.

Structural evolution, electrical and optical properties of AZO films ...

Indian Academy of Sciences (India)

Administrator

Aluminum-doped zinc oxide (AZO) target was fabricated using AZO ... All AZO films show c-axis preferred orientation and hexagonal structure. With increasing film thick- ness from 153 to 1404 nm, the crystallinity was improved and the angle of (002) peak was close to ... For observing grain boundary and size, the target was.

Azo dye decolorization assisted by chemical and biogenic sulfide

Energy Technology Data Exchange (ETDEWEB)

Prato-Garcia, Dorian [Laboratory for Research on Advanced Processes for Water Treatment, Unidad Académica Juriquilla, Instituto de Ingeniería, Universidad Nacional Autónoma de México, Blvd. Juriquilla 3001, Querétaro 76230 (Mexico); Cervantes, Francisco J. [División de Ciencias Ambientales, Instituto Potosino de Investigación Científica y Tecnológica, Camino a la Presa de San José 2055, San Luis Potosí 78216 (Mexico); Buitrón, Germán, E-mail: gbuitronm@ii.unam.mx [Laboratory for Research on Advanced Processes for Water Treatment, Unidad Académica Juriquilla, Instituto de Ingeniería, Universidad Nacional Autónoma de México, Blvd. Juriquilla 3001, Querétaro 76230 (Mexico)

2013-04-15

Highlights: ► Azo dyes were reduced efficiently by chemical and biogenic sulfide. ► Biogenic sulfide was more efficient than chemical sulfide. ► There was no competition between dyes and sulfate for reducing equivalents. ► Aromatic amines barely affected the sulfate-reducing process. -- Abstract: The effectiveness of chemical and biogenic sulfide in decolorizing three sulfonated azo dyes and the robustness of a sulfate-reducing process for simultaneous decolorization and sulfate removal were evaluated. The results demonstrated that decolorization of azo dyes assisted by chemical sulfide and anthraquinone-2,6-disulfonate (AQDS) was effective. In the absence of AQDS, biogenic sulfide was more efficient than chemical sulfide for decolorizing the azo dyes. The performance of sulfate-reducing bacteria in attached-growth sequencing batch reactors suggested the absence of competition between the studied azo dyes and the sulfate-reducing process for the reducing equivalents. Additionally, the presence of chemical reduction by-products had an almost negligible effect on the sulfate removal rate, which was nearly constant (94%) after azo dye injection.

Ion irradiation of AZO thin films for flexible electronics

Energy Technology Data Exchange (ETDEWEB)

Boscarino, Stefano; Torrisi, Giacomo; Crupi, Isodiana [IMM-CNR and Dipartimento di Fisica e Astronomia, Università di Catania, via S. Sofia 64, 95123 Catania (Italy); Alberti, Alessandra [CNR-IMM, via Strada VIII 5, 95121 Catania (Italy); Mirabella, Salvatore; Ruffino, Francesco [IMM-CNR and Dipartimento di Fisica e Astronomia, Università di Catania, via S. Sofia 64, 95123 Catania (Italy); Terrasi, Antonio, E-mail: antonio.terrasi@ct.infn.it [IMM-CNR and Dipartimento di Fisica e Astronomia, Università di Catania, via S. Sofia 64, 95123 Catania (Italy)

2017-02-01

Highlights: • Evidence of electrical good quality AZO ultra thin films without thermal annealing. • Evidence of the main role of Oxygen vs. structural parameters in controlling the electrical performances of AZO. • Evidence of the role of the ion irradiation in improving the electrical properties of AZO ultra thin films. • Synthesis of AZO thin films on flexible/plastic substrates with good electrical properties without thermal processes. - Abstract: Aluminum doped Zinc oxide (AZO) is a promising transparent conductor for solar cells, displays and touch-screen technologies. The resistivity of AZO is typically improved by thermal annealing at temperatures not suitable for plastic substrates. Here we present a non-thermal route to improve the electrical and structural properties of AZO by irradiating the TCO films with O{sup +} or Ar{sup +} ion beams (30–350 keV, 3 × 10{sup 15}–3 × 10{sup 16} ions/cm{sup 2}) after the deposition on glass and flexible polyethylene naphthalate (PEN). X-ray diffraction, optical absorption, electrical measurements, Rutherford Backscattering Spectrometry and Atomic Force Microscopy evidenced an increase of the crystalline grain size and a complete relief of the lattice strain upon ion beam irradiation. Indeed, the resistivity of thin AZO films irradiated at room temperature decreased of two orders of magnitude, similarly to a thermal annealing at 400 °C. We also show that the improvement of the electrical properties does not simply depend on the strain or polycrystalline domain size, as often stated in the literature.

Synthesis, spectroscopic, and molecular structure characterizations of some azo derivatives of 2-hydroxyacetophenone

Science.gov (United States)

Albayrak, Çiğdem; Gümrükçüoğlu, İsmail E.; Odabaşoğlu, Mustafa; İskeleli, Nazan Ocak; Ağar, Erbil

2009-08-01

Some novel azo compounds were prepared by the reaction of 2-hydroxyacetophenone with aniline and its substituted derivatives. The structures of synthesized azo compounds were determined by IR, UV-Vis, 1H NMR and 13C NMR spectroscopic techniques and the structures of some of these compounds were also determined by X-ray diffraction studies. Structural analysis using IR in solid state shows that the azo form is favoured in the azo compounds whereas UV-Vis analysis of the azo compounds in solution has shown that there is a azo and ionic form. The azo compounds in the basic solvents dimethylformamide (DMF) and dimethylsulfoxide (DMSO) are both azo and ionic form while these compounds in ethyl alcohol (EtOH) and chloroform (CHCl 3) are only azo form.

Azo polymers with electronical push and pull structures prepared via RAFT polymerization and its photoinduced birefringence behavior

Directory of Open Access Journals (Sweden)

2008-08-01

Full Text Available Two methacrylate monomers containing azo and electronical push and pull structure, e.g. 2-Methyl-acrylic-acid-2-{[4-(4-cyano-phenylazo-3-methyl-phenyl]-ethyl-amino-ethyl ester (MACP with cyano substituted and 2-Methylacrylic-acid-2-{ethyl-[4-(4-methoxy-phenylazo-3-methyl-phenyl]-amino}-ethyl ester (MAMP with methoxy substituted, were synthesized and polymerized using 2-cyanoprop-2-yl dithiobenzoate (CPDB as chain transfer agent and 2,2'-azobisisobutyronitrile (AIBN as initiator. The results showed that the polymerization displayed characteristics of ‘living’/controlled free radical polymerization. Thus, the obtained polymers, polyMACP (pMACP and polyMAMP (pMAMP, had controlled molecular weights and narrow molecular weights distribution. The chain extension experiments of pMACP and pMAMP using styrene as the second monomer were successfully carried out. The photo-induced trans-cis-trans isomerization kinetic of pMACP and pMAMP in chloroform solution were described. Marked differences in rate for the trans-cis and cis-trans isomerization of pMACP and pMAMP were observed in chloroform solution due to the different electronic effects in these two polymers. Photoinduced birefringence and surface relief grating (SRG of the pMACP and pMAMP were investigated in thin film state.

Understanding effects of chemical structure on azo dye decolorization characteristics by Aeromonas hydrophila

Energy Technology Data Exchange (ETDEWEB)

Hsueh, Chung-Chuan [Department of Chemical and Materials Engineering, National I-Lan University, I-Lan 260, Taiwan (China); Chen, Bor-Yann, E-mail: bychen@niu.edu.tw [Department of Chemical and Materials Engineering, National I-Lan University, I-Lan 260, Taiwan (China); Yen, Chia-Yi [Department of Chemical and Materials Engineering, National I-Lan University, I-Lan 260, Taiwan (China)

2009-08-15

This novel comparative study tended to disclose how the molecular structures present in seven azo dyes including two types of azo dyes (i.e., naphthol type azo dyes - Reactive Black 5 (RB 5), Reactive Blue 171 (RB 171), Reactive Green 19 (RG19), Reactive Red 198 (RR198), Reactive Red 141 (RR141) and non-naphthol type azo dyes - Direct Yellow 86 (DY86), Reactive Yellow 84 (RY84)) affected color removal capability of Aeromonas hydrophila. Generally speaking, the decolorization rate of naphthol type azo dye with hydroxyl group at ortho to azo bond was faster than that of non-naphthol type azo dye without hydroxyl group, except of RG19. The azo dyes with electron-withdrawing groups (e.g., sulfo group in RR198, RB5 and RR141) would be easier to be decolorized than the azo dyes with the electron-releasing groups (e.g., -NH-triazine in RB171 and RG19). In addition, the azo dyes containing more electron-withdrawing groups (e.g., RR198, RB5 and RR141) showed significantly faster rate of decolorization. The azo dyes with electron-withdrawing groups (e.g., sulfo group) at para and ortho to azo bond (e.g., RR198, RB5 and RR141) could be more preferred for color removal than those at meta (e.g., DY86 and RY84). The former azo dyes with para and ortho sulfo group provided more effective resonance effects to withdraw electrons from azo bond, causing azo dyes to be highly electrophilic for faster rates of reductive biodecolorization. However, since the ortho substituent caused steric hindrance near azo linkage(s), azo dyes with para substituent could be more favorable (e.g., SO{sub 2}(CH{sub 2}){sub 2}SO{sub 4}{sup -} in RR198 and RB5) than those with ortho substituent (e.g., sulfo group at RR141) for decolorization. Thus, the ranking of the position for the electron-withdrawing substituent in azo dyes to escalate decolorization was para > ortho > meta. This study suggested that both the positions of substituents on the aromatic ring and the electronic characteristics of

Changes in H-Reflex Recruitment After Trans-Spinal Direct Current Stimulation With Multiple Electrode Configurations

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Alexander Kuck

2018-03-01

Full Text Available Trans-spinal direct current stimulation (tsDCS is an electro-modulatory tool with possible application in the rehabilitation of spinal cord injury. TsDCS generates a small electric field, aiming to induce lasting, functional neuromodulation in the targeted neuronal networks. Earlier studies have shown significant modulatory effects after application of lumbar tsDCS. However, for clinical application, a better understanding of application specific factors is required. Our goal was to investigate the effect of different electrode configurations using lumbar spinal tsDCS on spinal excitability. We applied tsDCS (2.5 mA, 15 min in 10 healthy subjects with three different electrode configurations: (1 Anode and cathode placed over vertebra T11, and the posterior left shoulder respectively (LSC-S (one polarity, and (2 Both electrodes placed in equal distance (ED (7 cm above and below vertebra T11, investigated for two polarities (ED-Anodal/Cathodal. The soleus H-Reflex is measured before, during and after tsDCS in either electrode configuration or a sham condition. To account for genetic predispositions in response to direct current stimulation, subject BDNF genotype was assessed. Stimulation in configuration ED-Cathodal induced an amplitude reduction of the H-reflex, 30 min after tsDCS with respect to baseline, whereas none of the other configurations led to significant post intervention effects. BDNF genotype did not correlate with post intervention effects. Furthermore, we failed to replicate effects shown by a previous study, which highlights the need for a better understanding of methodological and subject specific influences on tsDCS outcome. The H-reflex depression after tsDCS (Config. ED-Cathodal provides new insights and may foster our understanding of the working mechanism of tsDCS.

Effects of reduction products of ortho-hydroxyl substituted azo dyes on biodecolorization of azo dyes

International Nuclear Information System (INIS)

Liu Guangfei; Wang Jing; Lu Hong; Jin Ruofei; Zhou Jiti; Zhang Long

2009-01-01

The mediated effects of reduction products of some ortho-hydroxyl substituted azo dyes on biodecolorization were investigated. The results indicated that the addition of reduction products could effectively accelerate dye decolorization by Shigella sp. QRZ-1. The best accelerating effect was obtained with the addition of reduction products of Acid Red 14 (AR14), resulting in an over 3-fold increase in decolorization efficiency of many azo dyes. In sequencing batch reactor experiments, the accelerating effect of reduction products of AR14 was more obvious (1.5-fold) during the startup of the system. When the dye concentration was increased to 500 mg L -1 , the accelerated decolorization efficiency was still maintained around 95%. The presence of AR14 in the feed enhanced the decolorization performance of anaerobic sludge, indicating that the strategy may be beneficial for practical application. 1-Naphthol-2-amino-4-sulfonic acid, which is one of the reduction products of AR14, may function as redox mediator to speed up azo dye biodecolorization.

2,3-trans-3,4-trans-3,4-Dihydroxy-L-proline: An amino acid in toxic peptides of Amanita virosa mushrooms

Science.gov (United States)

Buku, A.; Faulstich, H.; Wieland, T.; Dabrowski, J.

1980-01-01

Among the four possible stereoisomers of 3,4-dihydroxy-L-proline,2,3-trans-3,4-trans-3,4-dihydroxy-L-proline (IV) had not been found in nature previously. It has now been detected as a component of virotoxins, toxic peptides of Amanita virosa mushrooms. Because periodate failed to effect an oxidative glycol splitting reaction, the two hydroxyl groups in positions 3 and 4 were expected to be in a trans configuration. Furthermore, the formation of a 4-lactone on treatment with acids pointed to the carboxyl group and the hydroxyl group at position 4 being in a cis configuration. These results are in agreement with structure IV only. Final proof for structure IV was given by NMR spectroscopy and direct comparison with the 2,3-cis-3,4-trans-3,4-dihydroxy-L-proline isomer. PMID:16592813

Biological wastewater treatment of azo dyes

Energy Technology Data Exchange (ETDEWEB)

Shaul, G.M.; Dempsey, C.R.; Dostal, K.A. (Environmental Protection Agency, Cincinnati, OH (USA))

1988-09-01

EPA Water Engineering Research Laboratory, Office of Research and Development, undertook a study to determine the fate of specific water soluble azo dye compounds in the activated sludge process (ASP). The study was approached by dosing the feed to the pilot ASP systems with various water soluble azo dyes and by monitoring each dye compound through the system, analyzing both liquid and sludge samples. The fate of the parent dye compound was assessed via mass balance calculations. These data could determine if the compound was removed by adsorption, apparent biodegradation, or not removed at all. The paper presents results for 18 dye compounds tested from June 1985 through August 1987. The study was conducted at EPAs Test and Evaluation Facility in Cincinnati, Ohio. The objective of this study was to determine the partitioning of water soluble azo dyes in the ASP.

Effects of reduction products of ortho-hydroxyl substituted azo dyes on biodecolorization of azo dyes

Energy Technology Data Exchange (ETDEWEB)

Liu Guangfei [Key Laboratory of Industrial Ecology and Environmental Engineering, Ministry of Education, School of Environmental and Biological Science and Technology, Dalian University of Technology, Linggong Road No. 2, Dalian 116024 (China); Wang Jing, E-mail: wangjingbio@yahoo.cn [Key Laboratory of Industrial Ecology and Environmental Engineering, Ministry of Education, School of Environmental and Biological Science and Technology, Dalian University of Technology, Linggong Road No. 2, Dalian 116024 (China); Lu Hong; Jin Ruofei; Zhou Jiti; Zhang Long [Key Laboratory of Industrial Ecology and Environmental Engineering, Ministry of Education, School of Environmental and Biological Science and Technology, Dalian University of Technology, Linggong Road No. 2, Dalian 116024 (China)

2009-11-15

The mediated effects of reduction products of some ortho-hydroxyl substituted azo dyes on biodecolorization were investigated. The results indicated that the addition of reduction products could effectively accelerate dye decolorization by Shigella sp. QRZ-1. The best accelerating effect was obtained with the addition of reduction products of Acid Red 14 (AR14), resulting in an over 3-fold increase in decolorization efficiency of many azo dyes. In sequencing batch reactor experiments, the accelerating effect of reduction products of AR14 was more obvious (1.5-fold) during the startup of the system. When the dye concentration was increased to 500 mg L{sup -1}, the accelerated decolorization efficiency was still maintained around 95%. The presence of AR14 in the feed enhanced the decolorization performance of anaerobic sludge, indicating that the strategy may be beneficial for practical application. 1-Naphthol-2-amino-4-sulfonic acid, which is one of the reduction products of AR14, may function as redox mediator to speed up azo dye biodecolorization.

Fullerene-catalyzed reduction of azo derivatives in water under UV irradiation

KAUST Repository

Guo, Yong; Li, Wengang; Yan, Jingjing; Moosa, Basem; Amad, Maan H.; Werth, Charles; Khashab, Niveen M.

2012-01-01

Metal-free fullerene (C60) was found to be an effective catalyst for the reduction of azo groups in basic aqueous solution under UV irradiation in the presence of NaBH4. Use of NaBH4 by itself is not sufficient to reduce the azo dyes without the assistance of a metal catalyst such as Pd and Ag. Experimental and theoretical results suggest that C 60 catalyzes this reaction by using its vacant orbital to accept the electron in the bonding orbital of azo dyes, which leads to the activation of the N=N bond. UV irradiation increases the ability of C60 to interact with electron-donor moieties in azo dyes. Filling a vacancy: Experimental and theoretical methods have been combined to show that C60-catalyzed reductions of azo compounds form aromatic amines under UV irradiation (see scheme). The obtained results show that C60 acts as an electron acceptor to catalyze the reduction of azo compounds, and the role of UV irradiation is to increase the ability of C60 to interact with electron-donor moieties in azo compounds. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Fullerene-catalyzed reduction of azo derivatives in water under UV irradiation

KAUST Repository

Guo, Yong

2012-09-27

Metal-free fullerene (C60) was found to be an effective catalyst for the reduction of azo groups in basic aqueous solution under UV irradiation in the presence of NaBH4. Use of NaBH4 by itself is not sufficient to reduce the azo dyes without the assistance of a metal catalyst such as Pd and Ag. Experimental and theoretical results suggest that C 60 catalyzes this reaction by using its vacant orbital to accept the electron in the bonding orbital of azo dyes, which leads to the activation of the N=N bond. UV irradiation increases the ability of C60 to interact with electron-donor moieties in azo dyes. Filling a vacancy: Experimental and theoretical methods have been combined to show that C60-catalyzed reductions of azo compounds form aromatic amines under UV irradiation (see scheme). The obtained results show that C60 acts as an electron acceptor to catalyze the reduction of azo compounds, and the role of UV irradiation is to increase the ability of C60 to interact with electron-donor moieties in azo compounds. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

40 CFR 721.2097 - Azo chromium complex dyestuff preparation (generic name).

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Azo chromium complex dyestuff... New Uses for Specific Chemical Substances § 721.2097 Azo chromium complex dyestuff preparation... substance identified generically as an azo chromium complex dyestuff preparation (PMN P-95-240) is subject...

High-Quality AZO/Au/AZO Sandwich Film with Ultralow Optical Loss and Resistivity for Transparent Flexible Electrodes.

Science.gov (United States)

Zhou, Hua; Xie, Jing; Mai, Manfang; Wang, Jing; Shen, Xiangqian; Wang, Shuying; Zhang, Lihua; Kisslinger, Kim; Wang, Hui-Qiong; Zhang, Jinxing; Li, Yu; Deng, Junhong; Ke, Shanming; Zeng, Xierong

2018-05-09

Transparent flexible electrodes are in ever-growing demand for modern stretchable optoelectronic devices, such as display technologies, solar cells, and smart windows. Such sandwich-film-electrodes deposited on polymer substrates are unattainable because of the low quality of the films, inducing a relatively large optical loss and resistivity as well as a difficulty in elucidating the interference behavior of light. In this article, we report a high-quality AZO/Au/AZO sandwich film with excellent optoelectronic performance, e.g., an average transmittance of about 81.7% (including the substrate contribution) over the visible range, a sheet resistance of 5 Ω/sq, and a figure-of-merit (FoM) factor of ∼55.1. These values are well ahead of those previously reported for sandwich-film-electrodes. Additionally, the interference behaviors of light modulated by the coat and metal layers have been explored with the employment of transmittance spectra and numerical simulations. In particular, a heater device based on an AZO/Au/AZO sandwich film exhibits high performance such as short response time (∼5 s) and uniform temperature field. This work provides a deep insight into the improvement of the film quality of the sandwich electrodes and the design of high-performance transparent flexible devices by the application of a flexible substrate with an atomically smooth surface.

cis–trans Isomerization of silybins A and B

Directory of Open Access Journals (Sweden)

Michaela Novotná

2014-05-01

Full Text Available Methods were developed and optimized for the preparation of the 2,3-cis- and the 10,11-cis-isomers of silybin by the Lewis acid catalyzed (BF3∙OEt2 isomerization of silybins A (1a and B (1b (trans-isomers. The absolute configuration of all optically pure compounds was determined by using NMR and comparing their electronic circular dichroism data with model compounds of known absolute configurations. Mechanisms for cis–trans-isomerization of silybin are proposed and supported by quantum mechanical calculations.

Light sensitive polymer obtained by dispersion of azo-functionalized POSS nanoparticles

Energy Technology Data Exchange (ETDEWEB)

Miniewicz, A., E-mail: andrzej.miniewicz@pwr.edu.pl [Advanced Materials Engineering and Modelling, Faculty of Chemistry, Wroclaw University of Technology, Wybrzeze Wyspianskiego 27, 50-370 Wroclaw (Poland); Tomkowicz, M.; Karpinski, P.; Sznitko, L. [Advanced Materials Engineering and Modelling, Faculty of Chemistry, Wroclaw University of Technology, Wybrzeze Wyspianskiego 27, 50-370 Wroclaw (Poland); Mossety-Leszczak, B. [Faculty of Chemistry, Rzeszow University of Technology, Al. Powstancow Warszawy 12, 35-959 Rzeszow (Poland); Dutkiewicz, M. [Faculty of Chemistry, Adam Mickiewicz University of Poznan, Umultowska 89 B, 61-614 Poznan (Poland)

2015-07-29

Highlights: • Nanocomposite material PMMA containing azo-functionalized POSS has been prepared. • Surface topographies of prepared films are porous and dependent on azo-POSS content. • Photo-induced optical anisotropies both static and dynamic have been characterized. - Abstract: Hybrid inorganic–organic nanoparticles based on cubic siloxane cage (RSiO{sub 3/2}){sub 8}, known as polyhedral oligosilsesquioxane (POSS), have been functionalized by eight groups of azo-benzene mesogens and dispersed in poly(methyl methacrylate) PMMA matrix. Presence of azo-benzene units adds an important light-driven functionality to the system due to their photoisomerization resulting in refractive index and/or absorption changes of the whole system. The polymer films containing various concentrations of azo-POSS nanoparticles show remarkable changes of surface morphology being either transparent (at low POSS concentration) or highly scattering (at high POSS concentration) for visible light. Surface structures were examined by optical microscopy as well as by atomic force microscopy (AFM). Results of photoinduced alignment are discussed in the framework of light-induced modification of the aliphatic chains containing azo-benzene photoisomerizing moieties and self-organization process.

Light sensitive polymer obtained by dispersion of azo-functionalized POSS nanoparticles

International Nuclear Information System (INIS)

Miniewicz, A.; Tomkowicz, M.; Karpinski, P.; Sznitko, L.; Mossety-Leszczak, B.; Dutkiewicz, M.

2015-01-01

Highlights: • Nanocomposite material PMMA containing azo-functionalized POSS has been prepared. • Surface topographies of prepared films are porous and dependent on azo-POSS content. • Photo-induced optical anisotropies both static and dynamic have been characterized. - Abstract: Hybrid inorganic–organic nanoparticles based on cubic siloxane cage (RSiO 3/2 ) 8 , known as polyhedral oligosilsesquioxane (POSS), have been functionalized by eight groups of azo-benzene mesogens and dispersed in poly(methyl methacrylate) PMMA matrix. Presence of azo-benzene units adds an important light-driven functionality to the system due to their photoisomerization resulting in refractive index and/or absorption changes of the whole system. The polymer films containing various concentrations of azo-POSS nanoparticles show remarkable changes of surface morphology being either transparent (at low POSS concentration) or highly scattering (at high POSS concentration) for visible light. Surface structures were examined by optical microscopy as well as by atomic force microscopy (AFM). Results of photoinduced alignment are discussed in the framework of light-induced modification of the aliphatic chains containing azo-benzene photoisomerizing moieties and self-organization process

Fabrication of AZO TCO Films by RF-sputtering and Their Physical Properties

Directory of Open Access Journals (Sweden)

Jang T.S.

2016-01-01

Full Text Available We report on the fabrication of Al-doped ZnO (AZO transparent-conductive oxide (TCO films on glass substrates by RF-sputtering, their physical properties, and the effect of thermal annealing on the AZO TCO films. The AZO films on glass substrates have a preferred orientation of the c-axis, irrespective of deposition conditions, which means that the AZO films have textured structures along the c-axis. The film thickness and surface roughness in the AZO films are proportional to plasma power and deposition time, while they are inverse-proportional to working gas ratio and working pressure. The AZO films have the optical transmittance over 80 % in the wavelength range of 400 – 1000 nm, irrespective of deposition conditions. The plasma power and the deposition time relatively give a large influence on the optical transmittance, compared to the working gas ratio and the working pressure. The AZO films deposited at room temperature have poor electrical properties, while the thermal annealing under Ar ambient significantly improves the electrical conductivity of the AZO films: an as-deposited sample has an electrical resistivity of 87 Wcm and an electron concentration of 1.3´1017 cm−3, while the annealed sample has an electrical resistivity of 3.7´10-2 Wcm and an electron concentration of 1.2´1020 cm−3.

Degradação redutiva de azo-corantes utilizando-se ferro metálico Reductive degradation of azo-dyes by metallic iron

Directory of Open Access Journals (Sweden)

Cláudio Lima de Souza

2006-03-01

Full Text Available Corantes azo são extensivamente utilizados em processos de tingimento de fibras têxteis, sendo caracterizados por elevada resistência frente a processos aeróbios de biodegradação e, por conseqüência, persistência nos processos convencionais de tratamento de resíduos. Neste trabalho reporta-se a degradação redutiva de corantes azo, utilizando-se ferro metálico. Em condições experimentais otimizadas (pH 7 e 10 g de lã de aço comercial a completa descoloração do corante modelo (preto reativo 5 foi conseguida em um sistema contínuo, operando com tempos de retenção de 6 min. Nestas condições, o ferro solubilizado alcança concentrações compatíveis com os limites impostos pela atual legislação brasileira (12 mg L-1. Trata-se de um resultado bastante promissor, principalmente levando-se em consideração o caráter recalcitrante dos azo corantes e a simplicidade do sistema proposto.Azo dyes are extensively used in textile dying processes and are characterized by extreme resistance to biodegradation and consequently persistence during conventional wastewater treatment processes. In this work the reductive degradation of azo dyes was studied using zero-valent iron. At optimized experimental conditions (pH 7 and 10 g of commercial iron wool complete decolorization of the model dye (reactive black 5 was afforded in a continuous system operating with hydraulic retention time of 6 min. At these conditions the released total soluble iron reaches a concentration compatible with the limits imposed by the current Brazilian legislation (12 mg L-1. That is a very promising result, mainly taking into account the high recalcitrant character of azo dyes and the simplicity of the proposed system.

Azo biphenyl polyurethane: Preparation, characterization and application for optical waveguide switch

Science.gov (United States)

Jiang, Yan; Da, Zulin; Qiu, Fengxian; Yang, Dongya; Guan, Yijun; Cao, Guorong

2018-01-01

Azo waveguide polymers are of particular interest in the design of materials for applications in optical switch. The aim of this contribution was the synthesis and thermo-optic waveguide switch properties of azo biphenyl polyurethanes. A series of monomers and azo biphenyl polyurethanes (Azo BPU1 and Azo BPU2) were synthesized and characterized by FT-IR, UV-Vis spectroscopy and 1H NMR. The physical and mechanical properties of thin polymer films were measured. The refractive index and thermo-optic coefficient (dn/dT) of polymer films were investigated for TE (transversal electric) polarizations by ATR technique. The transmission loss of film was measured using the Charge Coupled Device digital imaging devices. The results showed the Azo BPU2 containing chiral azobenzene chromophore had higher dn/dT and lower transmission loss. Subsequently, a 1 × 2 Y-branch and 2 × 2 Mach-Zehnder optical switches based on the prepared polymers were designed and simulated. The results showed that the power consumption of all switches was less than 1.0 mW. Compared with 1 × 2 Y-branch optical switch, the 2 × 2 Mach-Zehnder optical switches based on the same polymer have the faster response time, which were about only 1.2 and 2.0 ms, respectively.

Defining a stable water isotope framework for isotope hydrology application in a large trans-boundary watershed (Russian Federation/Ukraine).

Science.gov (United States)

Vystavna, Yuliya; Diadin, Dmytro; Huneau, Frédéric

2018-05-01

Stable isotopes of hydrogen ( 2 H) and oxygen ( 18 O) of the water molecule were used to assess the relationship between precipitation, surface water and groundwater in a large Russia/Ukraine trans-boundary river basin. Precipitation was sampled from November 2013 to February 2015, and surface water and groundwater were sampled during high and low flow in 2014. A local meteoric water line was defined for the Ukrainian part of the basin. The isotopic seasonality in precipitation was evident with depletion in heavy isotopes in November-March and an enrichment in April-October, indicating continental and temperature effects. Surface water was enriched in stable water isotopes from upstream to downstream sites due to progressive evaporation. Stable water isotopes in groundwater indicated that recharge occurs mainly during winter and spring. A one-year data set is probably not sufficient to report the seasonality of groundwater recharge, but this survey can be used to identify the stable water isotopes framework in a weakly gauged basin for further hydrological and geochemical studies.

Synthesis, Characterization and Photoinduction of Optical Anisotropy in Liquid Crystalline Diblock Azo-Copolymers

DEFF Research Database (Denmark)

Forcén, P; Oriol, L; Sánchez, C

2007-01-01

Diblock copolymers with polymethyl methacrylate and side chain liquid crystalline WC) azopolymethacrylate blocks were synthesized by atom transfer radical polymerization (ATRP). The azobeazene content in these copolymers ranges from 52 to 7 wt %. For an azo conteat dowri to 20% they exhibit a LC...... anisotropy induced in these films by illumination with linearly polarized 488 nm light was studied and the resuits compared with those of the azo homopolymer and of a random copolymer with a similar composition. The formation of azo aggregates inside the azo blocks is strongly reduced in going from...... the homopolymer to the copolymers. Photoinduced azo orientation perpendicular to the 488 nm light polarization was found in aH the polymers. The orientational order parameter is very similar in the homopolymer and in the block copolymers with an azo content down to 20 wt %, while it is much lower in the random...

The influence of target erosion grade in the optoelectronic properties of AZO coatings growth by magnetron sputtering

Science.gov (United States)

Zubizarreta, C.; G-Berasategui, E.; Ciarsolo, I.; Barriga, J.; Gaspar, D.; Martins, R.; Fortunato, E.

2016-09-01

Aluminum-doped zinc oxide (AZO) transparent conductor coating has emerged as promising substitute to tin-doped indium oxide (ITO) as electrode in optoelectronic applications such as photovoltaics or light emitting diodes (LEDs). Besides its high transmission in the visible spectral region and low resistivity, AZO presents a main advantage over other candidates such as graphene, carbon nanotubes or silver nanowires; it can be deposited using the technology industrially implemented to manufacture ITO layers, the magnetron sputtering (MS). This is a productive, reliable and green manufacturing technique. But to guarantee the robustness, reproducibility and reliability of the process there are still some issues to be addressed, such as the effect and control of the target state. In this paper a thorough study of the influence of the target erosion grade in developed coatings has been performed. AZO films have been deposited from a ceramic target by RF MS. Structure, optical transmittance and electrical properties of the produced coatings have been analyzed as function of the target erosion grade. No noticeable differences have been found neither in optoelectronic properties nor in the structure of the coatings, indicating that the RF MS is a stable and consistent process through the whole life of the target.

Ion irradiation of AZO thin films for flexible electronics

Science.gov (United States)

Boscarino, Stefano; Torrisi, Giacomo; Crupi, Isodiana; Alberti, Alessandra; Mirabella, Salvatore; Ruffino, Francesco; Terrasi, Antonio

2017-02-01

Aluminum doped Zinc oxide (AZO) is a promising transparent conductor for solar cells, displays and touch-screen technologies. The resistivity of AZO is typically improved by thermal annealing at temperatures not suitable for plastic substrates. Here we present a non-thermal route to improve the electrical and structural properties of AZO by irradiating the TCO films with O+ or Ar+ ion beams (30-350 keV, 3 × 1015-3 × 1016 ions/cm2) after the deposition on glass and flexible polyethylene naphthalate (PEN). X-ray diffraction, optical absorption, electrical measurements, Rutherford Backscattering Spectrometry and Atomic Force Microscopy evidenced an increase of the crystalline grain size and a complete relief of the lattice strain upon ion beam irradiation. Indeed, the resistivity of thin AZO films irradiated at room temperature decreased of two orders of magnitude, similarly to a thermal annealing at 400 °C. We also show that the improvement of the electrical properties does not simply depend on the strain or polycrystalline domain size, as often stated in the literature.

Relative Stability of cis- and trans-Hydrindanones

Directory of Open Access Journals (Sweden)

Motoo Tori

2015-01-01

Full Text Available The relative stabilities of several cis- and trans-hydrindanones were compared using both isomerization experiments and MM2 calculations. The generally believed rule that cis-hydrindanones are more stable than trans-isomers is applicable, but is not always true. This review introduces examples, mainly from studies in our laboratory, to explain these facts.

Low-temperature, solution-processed aluminum-doped zinc oxide as electron transport layer for stable efficient polymer solar cells

Energy Technology Data Exchange (ETDEWEB)

Zhu, Qianqian [College of Materials Science and Engineering, Qingdao University of Science and Technology, Qingdao 266042 (China); Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101 (China); Bao, Xichang, E-mail: baoxc@qibebt.ac.cn [Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101 (China); Yu, Jianhua [College of Materials Science and Engineering, Qingdao University of Science and Technology, Qingdao 266042 (China); Zhu, Dangqiang [Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101 (China); Zhang, Qian [College of Materials Science and Engineering, Qingdao University of Science and Technology, Qingdao 266042 (China); Gu, Chuantao [Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101 (China); Dong, Hongzhou [College of Materials Science and Engineering, Qingdao University of Science and Technology, Qingdao 266042 (China); Yang, Renqiang [Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101 (China); Dong, Lifeng, E-mail: DongLifeng@qust.edu.cn [College of Materials Science and Engineering, Qingdao University of Science and Technology, Qingdao 266042 (China); Department of Physics, Hamline University, St. Paul, MN 55104 (United States)

2016-04-30

A simple low-temperature solution-processed zinc oxide (ZnO) and aluminum-doped ZnO (AZO) were synthesized and investigated as an electron transport layer (ETL) for inverted polymer solar cells. A solar cell with a blend of poly(4,8-bis-alkyloxy-benzo[1,2-b:4,5-b′] dithiophene-alt-alkylcarbonyl-thieno [3,4-b] thiophene) and (6,6)-phenyl-C71-butyric acid methyl ester as an active layer and AZO as ETL demonstrates a high power conversion efficiency (PCE) of 7.36% under the illumination of AM 1.5G, 100 mW/cm{sup 2}. Compared to the cells with ZnO ETL (PCE of 6.85%), the PCE is improved by 7.45% with the introduction of an AZO layer. The improved PCE is ascribed to the enhanced short circuit current density, which results from the electron transport property of the AZO layer. Moreover, AZO is a more stable interfacial layer than ZnO. The PCE of the solar cells with AZO as ETL retain 85% of their original value after storage for 120 days, superior to the 39% of cells with ZnO ETL. The results above indicate that a simple low-temperature solution-processed AZO film is an efficient and economical ETL for high-performance inverted polymer solar cells. Due to its environmental friendliness, good electrical properties, and simple preparation approach, AZO has the potential to be applied in high-performance, large-scale industrialization of solar cells and other electronic devices. - Highlights: • ZnO and AZO were synthesized by a simple low-temperature solution-processed method. • AZO films show high transmittance and conductivity. • The photovoltaic performance can be improved with AZO as ETL. • AZO-based devices demonstrate excellent stability, with 85% retained after 120 days.

Enhanced optical and electrical properties of Ni inserted ITO/Ni/AZO tri-layer structure for photoelectric applications

Energy Technology Data Exchange (ETDEWEB)

Kumar, M. Melvin David; Kim, Hyunki [Department of Electrical Engineering, Incheon National University, Incheon 406772 (Korea, Republic of); Park, Yun Chang [Measurement and Analysis Division, National Nanofab Center (NNFC), Daejeon 305-806 (Korea, Republic of); Kim, Joondong, E-mail: joonkim@incheon.ac.kr [Department of Electrical Engineering, Incheon National University, Incheon 406772 (Korea, Republic of)

2015-05-15

Highlights: • Ni-embedding transparent conductor effectively reduces the resistivity. • Ni insertion improves the carrier mobility and collection efficiencies. • ITO/Ni/AZO is effective to improve photo-responses compared to ITO/AZO. - Abstract: A thin Ni layer of 5 nm thickness was deposited in between indium-tin-oxide (ITO) and aluminum-doped-zinc oxide (AZO) layers of 50 nm thickness each. The Ni inserting tri-layer structure (ITO/Ni/AZO) showed lower resistivity of 5.51 × 10{sup −4} Ωcm which is nearly 20 times lesser than 97.9 × 10{sup −4} Ωcm of bilayer structure (ITO/AZO). A thin Ni layer in between ITO and AZO enhanced the carrier concentration, mobility and photoresponse behaviors so that figure of merit (FOM) value of ITO/Ni/AZO device was greater than that of ITO/AZO device. ITO/Ni/AZO structure showed improved quantum efficiencies over a broad range of wavelengths (∼350–950 nm) compared to that of ITO/AZO bilayer structure, resulting in enhanced photoresponses. These results show that the optical, electrical and photoresponse properties of ITO/AZO structure could be enhanced by inserting Ni layer of 5 nm thickness in between ITO and AZO layers.

Density functional theory study of adsorption geometries and electronic structures of azo-dye-based molecules on anatase TiO2 surface for dye-sensitized solar cell applications.

Science.gov (United States)

Prajongtat, Pongthep; Suramitr, Songwut; Nokbin, Somkiat; Nakajima, Koichi; Mitsuke, Koichiro; Hannongbua, Supa

2017-09-01

Structural and electronic properties of eight isolated azo dyes (ArNNAr', where Ar and Ar' denote the aryl groups containing benzene and naphthalene skeletons, respectively) were investigated by density functional theory (DFT) based on the B3LYP/6-31G(d,p) and TD-B3LYP/6-311G(d,p) methods The effect of methanol solvent on the structural and electronic properties of the azo dyes was elucidated by employing a polarizable continuum model (PCM). Then, the azo dyes adsorbed onto the anatase TiO 2 (101) slab surface through a carboxyl group. The geometries and electronic structures of the adsorption complexes were determined using periodic DFT based on the PWC/DNP method. The calculated adsorption energies indicate that the adsorbed dyes preferentially take configuration of the bidentate bridging rather than chelating or monodentate ester-type geometries. Furthermore, the azo compounds having two carboxyl groups are coordinated to the TiO 2 surface more preferentially through the carboxyl group connecting to the benzene skeleton than through that connecting to the naphthalene skeleton. The dihedral angles (Φ B-N ) between the benzene- and naphthalene-skeleton moieties are smaller than 10° for the adsorbed azo compounds containing one carboxyl group. In contrast, Φ B-N > 30° are obtained for the adsorbed azo compounds containing two carboxyl groups. The almost planar conformations of the former appear to strengthen both π-electrons conjugation and electronic coupling between low-lying unoccupied molecular orbitals of the azo dyes and the conduction band of TiO 2 . On the other hand, such coupling is very weak for the latter, leading to a shift of the Fermi level of TiO 2 in the lower-energy direction. The obtained results are useful to the design and synthesize novel azo-dye-based molecules that give rise to higher photovoltaic performances of the dye-sensitized solar cells. Copyright © 2017 Elsevier Inc. All rights reserved.

BF3.SiO2: an efficient catalyst for the synthesis of azo dyes at room temperature

Directory of Open Access Journals (Sweden)

Bi Bi Fatemeh Mirjalili

2012-07-01

Full Text Available A rapid one-pot method has been developed for the synthesis of azo dyes via ‎sequential diazotization–diazo coupling of aromatic amines with coupling agents at room ‎temperature in the presence of BF3.SiO2 as acidic catalyst. The obtained aryl diazonium salts bearing silica supported boron tri-flouride counter ion‎ was sufficiently stable to be kept at room ‎temperature in the dry state.‎

Organic heterostructures deposited by MAPLE on AZO substrate

Science.gov (United States)

Socol, M.; Preda, N.; Stanculescu, A.; Breazu, C.; Florica, C.; Stanculescu, F.; Iftimie, S.; Girtan, M.; Popescu-Pelin, G.; Socol, G.

2017-09-01

Organic heterostructures based on poly(3-hexylthiophene) (P3HT) and fullerene (C60) as blends or multilayer were deposited on Al:ZnO (AZO) by Matrix-Assisted Pulsed Laser Evaporation (MAPLE) technique. The AZO layers were obtained by Pulsed Laser Deposition (PLD) on glass substrate, the high quality of the films being reflected by the calculated figure of merit. The organic heterostructures were investigated from morphological, optical and electrical point of view by atomic force microscopy (AFM), UV-vis spectroscopy, photoluminescence (PL) and current-voltage (I-V) measurements, respectively. The increase of the C60 content in the blend heterostructure has as result a high roughness. Compared with the multilayer heterostructure, those based on blends present an improvement in the electrical properties. Under illumination, the highest current value was recorded for the heterostructure based on the blend with the higher C60 amount. The obtained results showed that MAPLE is a useful technique for the deposition of the organic heterostructures on AZO as transparent conductor electrode.

Reversible Redox Chemistry of Azo Compounds for Sodium-Ion Batteries.

Science.gov (United States)

Luo, Chao; Xu, Gui-Liang; Ji, Xiao; Hou, Singyuk; Chen, Long; Wang, Fei; Jiang, Jianjun; Chen, Zonghai; Ren, Yang; Amine, Khalil; Wang, Chunsheng

2018-03-05

Sustainable sodium-ion batteries (SSIBs) using renewable organic electrodes are promising alternatives to lithium-ion batteries for the large-scale renewable energy storage. However, the lack of high-performance anode material impedes the development of SSIBs. Herein, we report a new type of organic anode material based on azo group for SSIBs. Azobenzene-4,4'-dicarboxylic acid sodium salt is used as a model to investigate the electrochemical behaviors and reaction mechanism of azo compound. It exhibits a reversible capacity of 170 mAh g -1 at 0.2C. When current density is increased to 20C, the reversible capacities of 98 mAh g -1 can be retained for 2000 cycles, demonstrating excellent cycling stability and high rate capability. The detailed characterizations reveal that azo group acts as an electrochemical active site to reversibly bond with Na + . The reversible redox chemistry between azo compound and Na ions offer opportunities for developing long-cycle-life and high-rate SSIBs. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Reversible photocontrol of molecular assemblies of metal complex containing azo-amphiphiles

International Nuclear Information System (INIS)

Einaga, Yasuaki; Mikami, Rie; Akitsu, Takashiro; Li, Guangming

2005-01-01

Photo-controllable molecular systems, [M(en) 2 ][Pt(en) 2 Cl 2 ](1) 4 (M 2+ =Pt 2+ , Pd 2+ and en=ethylenediamine), have been designed by the self-assembly of chloride-bridged platinum/palladium complexes and photochromic amphiphiles of the azobenzene derivative, 4-[4-(N-methyl-N-n-dodecylamino)phenylazo]benzene sulfonic acid (designated as compound 1). Reversible structural changes caused by cis-trans photoisomerization of azo groups in compound 1 were observed by alternating illumination of UV and visible light. Visible illumination resulted in the formation of the plate-like structures, whereas UV illumination resulted in fragmentation of the assembling structures. Reversible changes were observed in the electronic states of the chloride-bridged platinum/palladium complexes; the plate-like structures exhibited charge transfer absorption of chloride-bridged platinum complexes and delocalized Pt(II)/Pt(IV) states, while the fragments of the separated complexes exhibited no charge transfer bands. As a consequence, we have discovered that the reversible structural changes in this system could be controlled by photoillumination

Re-evaluation of azo dyes as food additives

DEFF Research Database (Denmark)

Pratt, Iona; Larsen, John Christian; Mortensen, Alicja

2013-01-01

additives to be assessed by the Scientific Committee on Food, many years ago, (ii) because of concern regarding possible health effects of artificial colours arising since the original evaluations.Concerns includedbehavioural effects in children, allergic reactions, genotoxicity and possible carcinogenicity......Aryl azo compounds are widely used as colorants (azo dyes) in a wide range of products including textiles, leather, paper, cosmetics, pharmaceuticals and food.As part of its systematic re-evaluation of food additives, the European Food Safety Authority (EFSA) has carried out new risk assessments...

Ordered ZnO/AZO/PAM nanowire arrays prepared by seed-layer-assisted electrochemical deposition

International Nuclear Information System (INIS)

Shen, Yu-Min; Pan, Chih-Huang; Wang, Sheng-Chang; Huang, Jow-Lay

2011-01-01

An Al-doped ZnO (AZO) seed layer is prepared on the back side of a porous alumina membrane (PAM) substrate by spin coating followed by annealing in a vacuum at 400 °C. Zinc oxide in ordered arrays mediated by a high aspect ratio and an ordered pore array of AZO/PAM is synthesized. The ZnO nanowire array is prepared via a 3-electrode electrochemical deposition process using ZnSO 4 and H 2 O 2 solutions at a potential of − 1 V (versus saturated calomel electrode) and temperatures of 65 and 80 °C. The microstructure and chemical composition of the AZO seed layer and ZnO/AZO/PAM nanowire arrays are characterized by field emission scanning electron microscopy (FE-SEM), high-resolution transmission electron microscopy (HR-TEM), and energy-dispersive X-ray spectroscopy (EDS). Results indicate that the ZnO/AZO/PAM nanowire arrays were assembled in the nanochannel of the porous alumina template with diameters of 110–140 nm. The crystallinity of the ZnO nanowires depends on the AZO seed layer during the annealing process. The nucleation and growth process of ZnO/AZO/PAM nanowires are interpreted by the seed-layer-assisted growth mechanism.

Rigid nonproteinogenic cyclic amino acids as ligands for glutamate receptors: trans-tris(homoglutamic) acids

DEFF Research Database (Denmark)

Meyer, Udo; Bisel, Philippe; Bräuner-Osborne, Hans

2005-01-01

The second-generation asymmetric synthesis of the trans-tris(homoglutamic) acids reported herein proceeds via Strecker reaction of chiral ketimines, obtained from condensation of racemic 2-ethoxycarbonylmethylcyclopentanone and commercially available (S)- and (R)-1-phenylethylamine, respectively......) yielded diastereomeric mixtures of secondary alpha-amino amido-esters, which after separation were hydrogenolyzed and hydrolyzed each to the enantiomeric trans-1-amino-2-carboxymethylcyclopentanecarboxylic acids. Their configuration was completely established by NMR methods, CD spectra, and X-ray analysis...... of the trans-1S,2R-configured secondary alpha-amino amido-ester. In receptor binding assays and functional tests, trans-1S,2R-1-amino-2-carboxymethylcyclopentanecarboxylic acid hydrochloride was found to behave as a selective mGluR(2)-antagonist without relevant binding properties at iGluRs....

Trans-Z-source Neutral Point Clamped inverter

DEFF Research Database (Denmark)

Mo, W.; Loh, P. C.; Li, D.

2012-01-01

Transformer based Z-source (trans-Z-source) inverters are recently proposed by extending the traditional Z-source inverter with higher buck-boost capability as well as reducing the passive components at the same time. Multi-Level Z-source inverters are single-stage topological solutions used...... for buck-boost energy conversion with all the favourable advantages of multi-level switching retained. This paper presents three-level trans-Z-source Neutral Point Clamped (NPC) inverter topology, which achieves both the advantages of trans-Z-source and three-level NPC inverter configuration. With proper...... modulation scheme, the three-level trans-Z-source inverter can function with minimum of six device commutations per half carrier cycle (same as the traditional buck NPC inverter), while maintaining to produce the designed volt-sec average and inductive voltage boosting at ac output terminals. The designed...

Azo compounds as a family of organic electrode materials for alkali-ion batteries.

Science.gov (United States)

Luo, Chao; Borodin, Oleg; Ji, Xiao; Hou, Singyuk; Gaskell, Karen J; Fan, Xiulin; Chen, Ji; Deng, Tao; Wang, Ruixing; Jiang, Jianjun; Wang, Chunsheng

2018-02-27

Organic compounds are desirable for sustainable Li-ion batteries (LIBs), but the poor cycle stability and low power density limit their large-scale application. Here we report a family of organic compounds containing azo group (N=N) for reversible lithiation/delithiation. Azobenzene-4,4'-dicarboxylic acid lithium salt (ADALS) with an azo group in the center of the conjugated structure is used as a model azo compound to investigate the electrochemical behaviors and reaction mechanism of azo compounds. In LIBs, ADALS can provide a capacity of 190 mAh g -1 at 0.5 C (corresponding to current density of 95 mA g -1 ) and still retain 90%, 71%, and 56% of the capacity when the current density is increased to 2 C, 10 C, and 20 C, respectively. Moreover, ADALS retains 89% of initial capacity after 5,000 cycles at 20 C with a slow capacity decay rate of 0.0023% per cycle, representing one of the best performances in all organic compounds. Superior electrochemical behavior of ADALS is also observed in Na-ion batteries, demonstrating that azo compounds are universal electrode materials for alkali-ion batteries. The highly reversible redox chemistry of azo compounds to alkali ions was confirmed by density-functional theory (DFT) calculations. It provides opportunities for developing sustainable batteries.

Decolourization and degradation of azo Dye, Synozol Red HF6BN ...

African Journals Online (AJOL)

Decolourization and degradation of azo Dye, Synozol Red HF6BN, by Pleurotus ostreatus. Sidra Ilyas, Skinder Sultan Sultan, Abdul Rehman. Abstract. The present paper focuses on the use of fungus, Pleurotus ostreatus, to decolorize and degrade azo dye, Synazol Red HF6BN. Decolorization study showed that P.

Syntheses of Azo-Imine Derivatives from Vanillin as an Acid Base Indicator

Directory of Open Access Journals (Sweden)

Bambang Purwono

2013-05-01

Full Text Available Preparations of azo, imine and azo-imine derivatives from vanillin as an indicator of acid-base titration have been carried out. The azo derivative of 4-hydroxy-3-methoxy-5-(phenylazobenzaldehyde 2 was produced by diazotitation reaction of vanillin in 37.04% yield. The azo product was then refluxed with aniline in ethanol to yield azo-imine derivatives, 2-methoxy-6-(phenylazo-4-((phenyliminomethylphenol 1 in 82.21% yield. The imine derivative, 2-methoxy-4-((phenyliminomethyl-phenol 3 was obtained by refluxing of vanillin and aniline mixture in ethanol solvent and produced 82.17% yield. The imine product was then reacted with benzenediazonium chloride salt. However, the products indicated hydrolyzed product of 4-hydroxy-3-methoxy-5-(phenylazobenzaldehyde 2 in 22.15% yield. The 2-methoxy-4-((phenyliminomethylphenol 2 could be used as an indicator for titration of NaOH by H2C2O4 with maximum concentration of H2C2O4 0.1 M while the target compound 1 could be used as titration indicator for titration of NaOH with H2C2O4 with same result using phenolphthalein indicator.

Evaluation of biodecolorization of the textile azo dye by halophilic archaea

Directory of Open Access Journals (Sweden)

Masoomeh Selseleh Hassan-Kiadehi

2017-09-01

Discussion and conclusion: In conclusion, our results indicate that halophilic archaea have very high potential to decolorize azo dyes. Regarding high amounts of salts in textile wastewaters, using such microorganisms which can tolerate the harsh environment in order to decolorize azo dyes, could be a new approach in this field.

Analysis of Trans Fat in Edible Oils with Cooking Process

Science.gov (United States)

Song, Juhee; Park, Joohyeok; Jung, Jinyeong; Lee, Chankyu; Gim, Seo Yeoung; Ka, HyeJung; Yi, BoRa; Kim, Mi-Ja; Kim, Cho-il

2015-01-01

Trans fat is a unsaturated fatty acid with trans configuration and separated double bonds. Analytical methods have been introduced to analyze trans fat content in foods including infrared (IR) spectroscopy, gas chromatography (GC), Fourier transform-infrared (FT-IR) spectroscopy, reverses-phase silver ion high performance liquid chromatography, and silver nitrate thin layer chromatography. Currently, FT-IR spectroscopy and GC are mostly used methods. Trans fat content in 6 vegetable oils were analyzed and processing effects including baking, stir-frying, pan-frying, and frying on the formation of trans fat in corn oil was evaluated by GC. Among tested vegetable oils, corn oil has 0.25 g trans fat/100 g, whereas other oils including rapeseed, soybean, olive, perilla, and sesame oils did not have detectable amount of trans fat content. Among cooking methods, stir-frying increased trans fat in corn oil whereas baking, pan-frying, and frying procedures did not make changes in trans fat content compared to untreated corn oils. However, the trans fat content was so low and food label can be declared as ‘0’ trans based on the regulation of Ministry of Food ad Drug Safety (MFDS) (edible oil). PMID:26483890

Effect of AZO on GO-NO-GO radiation indicator

International Nuclear Information System (INIS)

Hasan Sham; Taiman Kadni; Noriah Mod Ali

2002-01-01

The purpose of the study is to evaluate the effect of Azo group dyes as an radiation indicator. Dimethyl Yellow, Alizarin Red, Congo Red, Methyl Violet and Bromophenol Blue dyes were used to compare the capability of each dye to change colour in response to radiation. Sensitivity of single and incorporated dyes were identified by exposing them to 5-50 kGy gamma radiation. The result shows that the Azo group is more sensitive to radiation compare to other groups. (Author)

A novel ITO/AZO/SiO2/p-Si frame SIS heterojunction fabricated by magnetron sputtering

International Nuclear Information System (INIS)

He, Bo; Wang, HongZhi; Li, YaoGang; Ma, ZhongQuan; Xu, Jing; Zhang, QingHong; Wang, ChunRui; Xing, HuaiZhong; Zhao, Lei; Rui, YiChuan

2013-01-01

Highlights: •Because the ITO/AZO double films lead to a great decrease of the lateral resistance. •The photon current can easily flow through top film entering the Cu front contact. •High photocurrent is obtained under a reverse bias. -- Abstract: The novel ITO/AZO/SiO 2 /p-Si SIS heterojunction has been fabricated by low temperature thermal oxidation an ultrathin silicon dioxide and RF sputtering deposition ITO/AZO double films on p-Si (1 0 0) polished substrate. The microstructural, optical and electrical properties of the ITO/AZO antireflection films were characterized by XRD, SEM, UV–VIS spectrophotometer, four point probe and Hall effect measurement, respectively. The results show that ITO/AZO films are of good quality. And XPS was carried out on the ultrathin SiO 2 film. The heterojunction shows strong rectifying behavior under a dark condition, which reveals that formation of a diode between AZO and p-Si. The ideality factor and the saturation current of this diode is 2.7 and 8.68 × 10 −5 A, respectively. High photocurrent is obtained under a reverse bias when the crystalline quality of ITO/AZO double films is good enough to transmit the light into p-Si. We can see that under reverse bias conditions the photocurrent of ITO/AZO/SiO 2 /p-Si SIS heterojunction is much higher than the photocurrent of AZO/SiO 2 /p-Si SIS heterojunction. Because the high quality crystallite and the good conductivity of ITO film which prepared by magnetron-sputtering on AZO film lead to a great decrease of the lateral resistance. The photon induced current can easily flow through ITO layer entering the Cu front contact. Thus, high photocurrent is obtained under a reverse bias

SYNTHESIS OF AZO COMPOUNDS DERIVATIVE FROM EUGENOL AND ITS APPLICATION AS A TITRATION INDICATOR

Directory of Open Access Journals (Sweden)

Bambang Purwono

2010-06-01

Full Text Available The synthesis of azo compounds from eugenol has been carried out by diazotation reaction. The diazonium salt was produced by reaction of aniline and sodium nitrite in acid condition at 0-5 °C temperature to yield benzenediazonium chloride salt. The salt was then reacted with eugenol to produce the azo derivatives. The azo product was analyzed by IR, 1H-NMR, dan GC-MS spectrometer. The results showed that the reaction of benzenediazonium chloride with eugenol gave 4-allyl-2-methoxy-6-hydroxyazobenzene in 34.27% yield for 30 minutes reaction. The derivative of azo compound was dissolved in ethanol and then the color changing was observed in range of pH 9.8-11.1 from yellow to red. Application for titration indicator for acetic acid titrated with sodium hydroxide showed error less than 3.20% compared with phenol phtaline indicator.   Keywords: Eugenol, Azo compound, titration indicator

Structure and reactivity of thiazolium azo dyes: UV-visible, resonance Raman, NMR, and computational studies of the reaction mechanism in alkaline solution.

Science.gov (United States)

Abbott, Laurence C; Batchelor, Stephen N; Moore, John N

2013-03-07

UV-visible absorption, resonance Raman, and (1)H NMR spectroscopy, allied with density functional theory (DFT) calculations, have been used to study the structure, bonding, and alkaline hydrolysis mechanism of the cationic thiazloium azo dye, 2-[2-[4-(diethylamino)phenyl]diazenyl]-3-methyl-thiazolium (1a), along with a series of six related dyes with different 4-dialkylamino groups and/or other phenyl ring substituents (2a-c, 3a-c) and the related isothiazolium azo dye, 5-[2-[4-(dimethylamino)phenyl]diazenyl]-2-methyl-isothiazolium (4). These diazahemicyanine dyes are calculated to have a similar low-energy structure that is cis, trans at the (iso)thiazolium-azo group, and for which the calculated Raman spectra provide a good match with the experimental data; the calculations on these structures are used to assign and discuss the transitions giving rise to the experimental spectra, and to consider the bonding and its variation between the dyes. UV-visible, Raman, and NMR spectra recorded from minutes to several weeks after raising the pH of an aqueous solution of 1a to ca. 11.5 show that the dominant initial step in the reaction is loss of diethylamine to produce a quinonimine (ca. hours), with subsequent reactions occurring on longer time scales (ca. days to weeks); kinetic analyses give a rate constant of 2.6 × 10(-2) dm(3) mol(-1) s(-1) for reaction of 1a with OH(-). UV-visible spectra recorded on raising the pH of the other dyes in solution show similar changes that are attributed to the same general reaction mechanism, but with different rate constants for which the dependence on structure is discussed.

Synthesis of azo pyridone dyes

Directory of Open Access Journals (Sweden)

Mijin Dušan Ž.

2011-01-01

Full Text Available Over 50% of all colorants which are used nowdays are azo dyes and pigments, and among them arylazo pyridone dyes (and pigments have became of interest in last several decades due to the high molar extinction coefficient, and the medium to high light and wet fastness properties. They find application generally as disperse dyes. The importance of disperse dyes increased in the 1970s and 1980s due to the use of polyester and nylon as the main synthetic fibers. Also, disperse dyes were used rapidly since 1970 in inks for the heat-transfer printing of polyester. The main synthetic route for the preparation of azo dyes is coupling reaction between an aromatic diazo compound and a coupling component. Of all dyes manufactured, about 60% are produced by this reaction. Arylazo pyridone dyes can be prepared from pyridone moiety as a coupling component, where substituent can be on nitrogen, and diazonim salts which can be derived from different substituted anilines or other heterocyclic derivatives. In addition, arylazo dyes containing pyridone ring can be prepared from arylazo diketones or arylazo ketoesters (obtained by coupling β-diketones or β-ketoesters with diazonim salts by condensation with cyanoacetamide. Disazo dyes can be prepared by tetrazotizing a dianiline and coupling it with a pyridone or by diazotizing aniline and coupling it with a dipyridone. Trisazo dyes can be also prepared by diazotizing of aniline and coupling it with a tripyridone or by hexazotizing a trianiline and coupling it with a pyridone. The main goal of this paper is to give a brief review on the synthesis of arylazo pyridone dyes due to the lack of such reviews. In addition, some properties of arylazo pyridone dyes as light fastness and azo-hydrazon tautomerism are disccused.

Acid-Base Properties of Azo Dyes in Solution Studied Using Spectrophotometry and Colorimetry

Science.gov (United States)

Snigur, D. V.; Chebotarev, A. N.; Bevziuk, K. V.

2018-03-01

Colorimetry and spectrophotometry with chemometric data processing were used to study the acid-base properties of azo dyes in aqueous solution. The capabilities of both methods were compared. Ionization constants of all the functional groups of the azo compounds studied could be determined relative to the change in the specific color difference depending on the acidity of the medium. The colorimetric functions of ion-molecular forms of azo compounds used as an analytical signal allow us to obtain complete information on the acid-base equilibrium in a wide acidity range.

The effect of dioctyl sodium sulphosuccinate on tartrazine azo reduction by intestinal bacteria.

Science.gov (United States)

Allan, R J; Roxon, J J

1977-03-01

1. Washed whole-cell suspensions of Proteus vulgaris and micro-organisms from rat faeces, reductively cleave the azo bond of the food dye tartrazine under anaerobic conditions. 2. Dioctyl sodium sulphosuccinate, a common faecal softening laxative, when added to incubations in vitro at concentrations greater than 0.005%, increases tartrazine azo reduction in P. vulgaris whole-cell suspensions. 3. By contrast, concentrations of dioctyl sodium sulphosuccinate greater than 0.005% when added to incubations in vitro of rat faecal preparations, resulted in an inhibition of tartrazine azo reduction.

Synthesis and Characterization of a New Heterocyclic Azo Pigment

International Nuclear Information System (INIS)

Asniza, M.; Issam, A.M.; Khalil, H.P.S.A.

2011-01-01

A new heterocyclic coupling agent has been produced from the reaction of maleic anhydride and p-aminophenol, namely N-(4-hexahydrophenol)maleimide. The coupling agent underwent azo coupling reaction with aromatic amine, which is p-aminophenol to produce a new heterocyclic azo pigment. The pigment was then subjected to solubility, hiding power and light fastness test. Fourier Transform Infrared Spectroscopy (FTIR), Ultraviolet/ Visible (UV/Vis) Spectroscopy, and Nuclear Magnetic Resonance Spectroscopy ( 1 H-NMR, 13 C-NMR) were used to obtain the characteristics and structural features of the pigment. (author)

[The decolorization and biodegrading metabolism of azo dyes by Pseudomonas S-42].

Science.gov (United States)

Liu, Z P; Yang, H F

1989-12-01

Pseudomonas S-42 was capable of decolorizing azo dyes such as Diamira Brilliant Orange RR(DBO-RR), Direct Brown M (DBM), Eriochrome Brown R(EBR) and so on. The cell suspension, cell-free extract and purified enzyme of Pseud. S-42 could decolorize azo dyes under similar conditions: the optimum pH and temperature laid 7.0 and 37 degrees C respectively. The efficiencies of decolorizing of DBO-RR, DBM, EBR by intact cells stood more than 90%. When the cell concentration was 15 mg(wet)/ml and the reaction time was 5 hours, the decolorizing activity for above three azo dyes by intact cells were 1.75, 2.4, 0.95 micrograms dye/mg cell, respectively. Cell-free extract and purified enzyme could well express the decolorizing activity only under the anaerobic condition and added NADH. Purified enzyme belongs to azoreductase, its molecular weight is about 34,000-2000 daltons, and its Vmax and Km for DBO-RR are 13 mumol.mg protein-1.min-1 and 54 mumol/L. The results of the detection of the biodegrading products of DBO-RR by spectrophotometric and NaNO2 reactional methods showed that the biodegradation of azo dyes was initiated by the reduction cleavage of azo bonds. It was hypothesized that biodegrading metabolism pathway of DBO-RR by Pseudomonas S-42.

Ruminant and industrially produced trans fatty acids

DEFF Research Database (Denmark)

Stender, Steen; Astrup, Arne; Dyerberg, Jørn

2008-01-01

% of the fatty acids in trans form compared to the content in ruminant fat which generally does not exceed 6%. In Western Europe, including Scandinavia, the average daily intake of IP-TFA has decreased during the recent decade due to societal pressure and a legislative ban, whereas the intake of RP-TFA has......Fatty acids of trans configuration in our food come from two different sources - industrially produced partially hydrogenated fat (IP-TFA) used in frying oils, margarines, spreads, and in bakery products, and ruminant fat in dairy and meat products (RP-TFA). The first source may contain up to 60...

Chlorine disinfection of dye wastewater: Implications for a commercial azo dye mixture

International Nuclear Information System (INIS)

Vacchi, Francine Inforçato; Albuquerque, Anjaina Fernandes; Vendemiatti, Josiane Aparecida; Morales, Daniel Alexandre; Ormond, Alexandra B.; Freeman, Harold S.; Zocolo, Guilherme Julião; Zanoni, Maria Valnice Boldrin; Umbuzeiro, Gisela

2013-01-01

Azo dyes, the most widely used family of synthetic dyes, are often employed as colorants in areas such as textiles, plastics, foods/drugs/cosmetics, and electronics. Following their use in industrial applications, azo dyes have been found in effluents and various receiving waters. Chemical treatment of effluents containing azo dyes includes disinfection using chlorine, which can generate compounds of varying eco/genotoxicity. Among the widely known commercial azo dyes for synthetic fibers is C.I. Disperse Red 1. While this dye is known to exist as a complex mixture, reports of eco/genotoxicity involve the purified form. Bearing in mind the potential for adverse synergistic effects arising from exposures to chemical mixtures, the aim of the present study was to characterize the components of commercial Disperse Red 1 and its chlorine-mediated decoloration products and to evaluate their ecotoxicity and mutagenicity. In conducting the present study, Disperse Red 1 was treated with chlorine gas, and the solution obtained was analyzed with the aid of LC–ESI-MS/MS to identify the components present, and then evaluated for ecotoxicity and mutagenicity, using Daphnia similis and Salmonella/microsome assays, respectively. The results of this study indicated that chlorination of Disperse Red 1 produced four chlorinated aromatic compounds as the main products and that the degradation products were more ecotoxic than the parent dye. These results suggest that a disinfection process using chlorine should be avoided for effluents containing hydrophobic azo dyes such commercial Disperse Red 1. -- Highlights: ► Aqueous solutions of Disperse Red 1 were treated with chlorine. ► The chlorination products of Disperse Red 1 were identified using LC–ESI-MS/MS. ► Daphnia and Salmonella/microsome were employed for eco/genotoxicity testing. ► The chlorinated dye was more mutagenic than the dye itself. ► Chlorination should be avoided in effluents containing azo-dyes.

High Fidelity Modeling of Field-Reversed Configuration (FRC) Thrusters (Briefing Charts)

Science.gov (United States)

2017-05-24

THRUSTERS (Briefing Charts) Robert Martin , Eder Sousa, Jonathan Tran Air Force Research Laboratory (AFMC) AFRL/RQRS 1 Ara Drive Edwards AFB, CA 93524... Martin N/A HIGH FIDELITY MODELING OF FIELD-REVERSED CONFIGURATION (FRC) THRUSTERS Robert Martin1, Eder Sousa2, Jonathan Tran2 1AIR FORCE RESEARCH...Distribution is unlimited. PA Clearance No. 17314 MARTIN , SOUSA, TRAN (AFRL/RQRS) DISTRIBUTION A - APPROVED FOR PUBLIC RELEASE; DISTRIBUTION UNLIMITED. PA

Ohmic contacts on n-type β-Ga2O3 using AZO/Ti/Au

Directory of Open Access Journals (Sweden)

Patrick H. Carey IV

2017-09-01

Full Text Available AZO interlayers between n-Ga2O3 and Ti/Au metallization significantly enhance Ohmic contact formation after annealing at ≥ 300°C. Without the presence of the AZO, similar anneals produce only rectifying current-voltage characteristics. Transmission Line Measurements of the Au/Ti/AZO/Ga2O3 stacks showed the specific contact resistance and transfer resistance decreased sharply from as-deposited values with annealing. The minimum contact resistance and specific contact resistance of 0.42 Ω-mm and 2.82 × 10-5 Ω-cm2 were achieved after a relatively low temperature 400°C annealing. The conduction band offset between AZO and Ga2O3 is 0.79 eV and provides a favorable pathway for improved electron transport across this interface.

Ohmic contacts on n-type β-Ga2O3 using AZO/Ti/Au

Science.gov (United States)

Carey, Patrick H.; Yang, Jiancheng; Ren, F.; Hays, David C.; Pearton, S. J.; Jang, Soohwan; Kuramata, Akito; Kravchenko, Ivan I.

2017-09-01

AZO interlayers between n-Ga2O3 and Ti/Au metallization significantly enhance Ohmic contact formation after annealing at ≥ 30 0°C. Without the presence of the AZO, similar anneals produce only rectifying current-voltage characteristics. Transmission Line Measurements of the Au/Ti/AZO/Ga2O3 stacks showed the specific contact resistance and transfer resistance decreased sharply from as-deposited values with annealing. The minimum contact resistance and specific contact resistance of 0.42 Ω-mm and 2.82 × 10-5 Ω-cm2 were achieved after a relatively low temperature 40 0°C annealing. The conduction band offset between AZO and Ga2O3 is 0.79 eV and provides a favorable pathway for improved electron transport across this interface.

Reduction of azo dyes by flavin reductase from Citrobacter freundii A1

Directory of Open Access Journals (Sweden)

Mohd Firdaus Abdul-Wahab

2012-12-01

Full Text Available Citrobacter freundii A1 isolated from a sewage treatment facility was demonstrated to be able to effectively decolorize azo dyes as pure and mixed culture. This study reports on the investigation on the enzymatic systems involved. An assay performed suggested the possible involvement of flavin reductase (Fre as an azo reductase. A heterologouslyexpressed recombinant Fre from C. freundii A1 was used to investigate its involvement in the azo reduction process. Three model dyes were used, namely Acid Red 27 (AR27, Direct Blue 15 (DB15 and Reactive Black 5 (RB5. AR27 was found to be reduced the fastest by Fre, followed by RB5, and lastly DB15. Redox mediators nicotinamide adenine dinucleotide (NADH and riboflavin enhance the reduction, suggesting the redox activity of the enzyme. The rate and extent of reduction of the model dyes correlate well with the reduction potentials (Ep. The data presented here strongly suggest that Fre is one of the enzymes responsible for azo reduction in C. freundii A1, acting via an oxidation-reduction reaction.

Metabolism of azo dyes by human skin microbiota.

Science.gov (United States)

Stingley, Robin L; Zou, Wen; Heinze, Thomas M; Chen, Huizhong; Cerniglia, Carl E

2010-01-01

Reduction of Methyl Red (MR) and Orange II (Or II) by 26 human skin bacterial species was monitored by a rapid spectrophotometric assay. The analysis indicated that skin bacteria, representing the genera Staphylococcus, Corynebacterium, Micrococcus, Dermacoccus and Kocuria, were able to reduce MR by 74-100 % in 24 h, with only three species unable to reduce completely the dye in that time. Among the species tested, only Corynebacterium xerosis was unable to reduce Or II to any degree by 24 h, and only Staphylococcus delphini, Staphylococcus sciuri subsp. sciuri and Pseudomonas aeruginosa were able to reduce completely this dye within 24 h. MR reduction started with early-exponential growth in Staphylococcus aureus and Staphylococcus epidermidis, and around late-exponential/early-stationary growth in P. aeruginosa. Reduction of Or II, Ponceau S and Ponceau BS started during late-exponential/early-stationary growth for all three species. Using liquid chromatography/electrospray ionization mass spectrometry analyses, MR metabolites produced by Staph. aureus, Staph. epidermidis and P. aeruginosa were identified as N,N-dimethyl-p-phenylenediamine and 2-aminobenzoic acid. Searches of available genomic and proteomic data revealed that at least four of the staphylococci in this study, Staphylococcus haemolyticus, Staph. epidermidis, Staphylococcus cohnii and Staphylococcus saprophyticus, have hypothetical genes with 77, 76, 75 and 74 % sequence identity to azo1 encoding an azoreductase from Staph. aureus and hypothetical proteins with 82, 80, 72 and 74 % identity to Azo1, respectively. In addition, Staphylococcus capitis has a protein with 79 % identity to Azo1. Western analysis detected proteins similar to Azo1 in all the staphylococci tested, except Staph. delphini, Staph. sciuri subsp. sciuri and Staphylococcus auricularis. The data presented in this report will be useful in the risk assessment process for evaluation of public exposure to products containing these dyes.

Low resistance and transparent Ag/AZO ohmic contact to p-GaN

International Nuclear Information System (INIS)

Han, T.; Wang, T.; Gan, X. W.; Wu, H.; Shi, Y.; Liu, C.

2014-01-01

Silver (Ag)/ aluminum-doped zinc oxide (AZO) films were deposited on p-GaN by using electron beam evaporation. After the annealing process, current -voltage (I-V) measurements were carried out to determine the characteristic of the contacts. The Ag/AZO films annealed at 600 .deg. C were found to present an ohmic contact behavior. The specific contact resistance was calculated to be 9.76 x 10 -4 Ωcm 2 and the transmittance was over 80% for visibly light. The atomic force microscope was used to measure the aggregation of Ag grains which may have been the main factor in the formation of the Ag/AZO ohmic contact to p-GaN.

Chromophore Structure of Photochromic Fluorescent Protein Dronpa: Acid-Base Equilibrium of Two Cis Configurations.

Science.gov (United States)

Higashino, Asuka; Mizuno, Misao; Mizutani, Yasuhisa

2016-04-07

Dronpa is a novel photochromic fluorescent protein that exhibits fast response to light. The present article is the first report of the resonance and preresonance Raman spectra of Dronpa. We used the intensity and frequency of Raman bands to determine the structure of the Dronpa chromophore in two thermally stable photochromic states. The acid-base equilibrium in one photochromic state was observed by spectroscopic pH titration. The Raman spectra revealed that the chromophore in this state shows a protonation/deprotonation transition with a pKa of 5.2 ± 0.3 and maintains the cis configuration. The observed resonance Raman bands showed that the other photochromic state of the chromophore is in a trans configuration. The results demonstrate that Raman bands selectively enhanced for the chromophore yield valuable information on the molecular structure of the chromophore in photochromic fluorescent proteins after careful elimination of the fluorescence background.

Chemometric analysis of mass spectra of cis and trans fatty acid picolinyl esters

DEFF Research Database (Denmark)

Leth, Torben

1997-01-01

and trans fatty acids of C16:1, C18:1,n-9, C18:1,n-12, C18:2 and C22:1 in two- and three-dimensional score plots. With Soft Independent Modelling of Class Analogy (SIMCA), it is possible to calculate models that can predict from the mass spectra of unknown fatty acids whether they are of the cis or trans...... configuration, which is demonstrated for C18:1 trans from hardened margarine and butter....

Enhanced performance of a-IGZO thin-film transistors by forming AZO/IGZO heterojunction source/drain contacts

International Nuclear Information System (INIS)

Zou, Xiao; Fang, Guojia; Wan, Jiawei; Liu, Nishuang; Long, Hao; Wang, Haolin; Zhao, Xingzhong

2011-01-01

A low-cost Al-doped ZnO (AZO) thin film was deposited by radio-frequency magnetron sputtering with different Ar/O 2 flow ratios. The optical and electrical properties of an AZO film were investigated. A highly conductive AZO film was inserted between the amorphous InGaZnO (a-IGZO) channel and the metal Al electrode to form a heterojunction source/drain contact, and bottom-gate amorphous a-IGZO thin-film transistors (TFTs) with a high κ HfON gate dielectric were fabricated. The AZO film reduced the source/drain contact resistivity down to 79 Ω cm. Enhanced device performance of a-IGZO TFT with Al/AZO bi-layer S/D electrodes (W/L = 500/40 µm) was achieved with a saturation mobility of 13.7 cm 2 V −1 s −1 , a threshold voltage of 0.6 V, an on-off current ratio of 4.7 × 10 6 , and a subthreshold gate voltage swing of 0.25 V dec −1 . It demonstrated the potential application of the AZO film as a promising S/D contact material for the fabrication of the high performance TFTs

Strong guided mode resonant local field enhanced visible harmonic generation in an azo-polymer resonant waveguide grating.

Science.gov (United States)

Lin, Jian Hung; Tseng, Chun-Yen; Lee, Ching-Ting; Young, Jeff F; Kan, Hung-Chih; Hsu, Chia Chen

2014-02-10

Guided mode resonance (GMR) enhanced second- and third-harmonic generation (SHG and THG) is demonstrated in an azo-polymer resonant waveguide grating (RWG), comprised of a poled azo-polymer layer on top of a textured SU8 substrate with a thin intervening layer of TiO2. Strong SHG and THG outputs are observed by matching either in-coming fundamental- or out-going harmonic-wavelength to the GMR wavelengths of the azo-polymer RWG. Without the azo-polymer coating, pure TiO2 RWGs, do not generate any detectable SHG using a fundamental beam peak intensity of 2 MW/cm(2). Without the textured TiO2 layer, a planar poled azo-polymer layer results in 3650 times less SHG than the full nonlinear RWG structure under identical excitation conditions. Rigorous coupled-wave analysis calculations confirm that this enhancement of the nonlinear conversion is due to strong local electric fields that are generated at the interfaces of the TiO2 and azo-polymer layers when the RWG is excited at resonant wavelengths associated with both SHG and THG conversion processes.

AZO/Ag/AZO anode for resonant cavity red, blue, and yellow organic light emitting diodes

Energy Technology Data Exchange (ETDEWEB)

Gentle, A. R., E-mail: angus.gentle@uts.edu.au; Smith, G. B. [School of Mathematical and Physical Sciences and Institute of Nanoscale Technology, University of Technology Sydney, P.O. Box 123, Broadway, New South Wales 2007 (Australia); Yambem, S. D.; Burn, P. L.; Meredith, P. [Centre for Organic Photonics and Electronics, School of Chemistry and Molecular Biosciences and School of Mathematics and Physics, The University of Queensland, St Lucia, Queensland 4072 (Australia)

2016-06-28

Indium tin oxide (ITO) is the transparent electrode of choice for organic light-emitting diodes (OLEDs). Replacing ITO for cost and performance reasons is a major drive across optoelectronics. In this work, we show that changing the transparent electrode on red, blue, and yellow OLEDs from ITO to a multilayer buffered aluminium zinc oxide/silver/aluminium zinc oxide (AZO/Ag/AZO) substantially enhances total output intensity, with better control of colour, its constancy, and intensity over the full exit hemisphere. The thin Ag containing layer induces a resonant cavity optical response of the complete device. This is tuned to the emission spectra of the emissive material while minimizing internally trapped light. A complete set of spectral intensity data is presented across the full exit hemisphere for each electrode type and each OLED colour. Emission zone modelling of output spectra at a wide range of exit angles to the normal was in excellent agreement with the experimental data and hence could, in principle, be used to check and adjust production settings. These multilayer transparent electrodes show significant potential for both eliminating indium from OLEDs and spectrally shaping the emission.

The in situ generation and reactive quench of diazonium compounds in the synthesis of azo compounds in microreactors

OpenAIRE

Faith M. Akwi; Paul Watts

2016-01-01

Summary In this paper, a micro-fluidic optimized process for the continuous flow synthesis of azo compounds is presented. The continuous flow synthesis of Sudan II azo dye was used as a model reaction for the study. At found optimal azo coupling reaction temperature and pH an investigation of the optimum flow rates of the reactants for the diazotization and azo coupling reactions in Little Things Factory-MS microreactors was performed. A conversion of 98% was achieved in approximately 2.4 min...

(E-2-Acetyl-4-[(3-methylphenyldiazenyl]phenol: an X-ray and DFT study

Directory of Open Access Journals (Sweden)

Orhan Büyükgüngör

2010-03-01

Full Text Available The title compound, C15H14N2O2, an azo dye, displays a trans configuration with respect to the N=N bridge. The dihedral angle between the aromatic rings is 0.18 (14°. There is a strong intramolecular O—H...O hydrogen bond. Geometrical parameters, determined using X-ray diffraction techniques, are compared with those calculated by density functional theory (DFT, using hybrid exchange–correlation functional, B3LYP and semi-empirical (PM3 methods.

Experimental Study on Fabrication of AZO Transparent Electrode for Organic Solar Cell Using Selective Low-Temperature Atomic Layer Deposition

International Nuclear Information System (INIS)

Kim, Kicheol; Song, Gensoo; Kim, Hyungtae; Yoo, Kyunghoon; Kang, Jeongjin; Hwang, Junyoung; Lee, Sangho; Kang, Kyungtae; Kang, Heuiseok; Cho, Youngjune

2013-01-01

AZO (aluminum-doped zinc oxide) is one of the best candidate materials to replace Into (indium tin oxide) for TKOs (transparent conductive oxides) used in flat panel displays, organic light-emitting diodes (OLDS), and organic solar cells (OCSS). In the present study, to apply an AZO thin film to the transparent electrode of an organic solar cell, a low temperature selective atomic layer deposition (ALD) process was adopted to deposit an AZO thin film on a flexible polyethylene-naphthanate (Pen) substrate. The reactive gases for the ALD process were di-ethyl-zinc (De) and tri-methylaluminum (Tma) as precursors and H 2 O as an oxidant. The structural, electrical, and optical characteristics of the AZO thin film were evaluated. From the measured results of the electrical and optical characteristics of the AZO thin films deposited on the Pen substrates by Ald, it was shown that the Azo thin film appeared to be comparable to a commercially used Into thin film, which confirmed the feasibility of AZO as a TCO for flexible organic solar cells in the near future

Chlorine disinfection of dye wastewater: Implications for a commercial azo dye mixture

Energy Technology Data Exchange (ETDEWEB)

Vacchi, Francine Inforcato; Albuquerque, Anjaina Fernandes; Vendemiatti, Josiane Aparecida; Morales, Daniel Alexandre [Faculdade de Tecnologia, Universidade Estadual de Campinas, Limeira, SP, 13484-332 (Brazil); Ormond, Alexandra B.; Freeman, Harold S. [Department of Textile Engineering, Chemistry, and Science, North Carolina State University, Raleigh, NC 27695-8301 (United States); Zocolo, Guilherme Juliao; Zanoni, Maria Valnice Boldrin [Departamento de Quimica Analitica, Universidade Estadual Paulista Julio de Mesquita Filho, Instituto de Quimica de Araraquara, Araraquara, SP 14801-970 (Brazil); Umbuzeiro, Gisela, E-mail: giselau@ft.unicamp.br [Faculdade de Tecnologia, Universidade Estadual de Campinas, Limeira, SP, 13484-332 (Brazil)

2013-01-01

Azo dyes, the most widely used family of synthetic dyes, are often employed as colorants in areas such as textiles, plastics, foods/drugs/cosmetics, and electronics. Following their use in industrial applications, azo dyes have been found in effluents and various receiving waters. Chemical treatment of effluents containing azo dyes includes disinfection using chlorine, which can generate compounds of varying eco/genotoxicity. Among the widely known commercial azo dyes for synthetic fibers is C.I. Disperse Red 1. While this dye is known to exist as a complex mixture, reports of eco/genotoxicity involve the purified form. Bearing in mind the potential for adverse synergistic effects arising from exposures to chemical mixtures, the aim of the present study was to characterize the components of commercial Disperse Red 1 and its chlorine-mediated decoloration products and to evaluate their ecotoxicity and mutagenicity. In conducting the present study, Disperse Red 1 was treated with chlorine gas, and the solution obtained was analyzed with the aid of LC-ESI-MS/MS to identify the components present, and then evaluated for ecotoxicity and mutagenicity, using Daphnia similis and Salmonella/microsome assays, respectively. The results of this study indicated that chlorination of Disperse Red 1 produced four chlorinated aromatic compounds as the main products and that the degradation products were more ecotoxic than the parent dye. These results suggest that a disinfection process using chlorine should be avoided for effluents containing hydrophobic azo dyes such commercial Disperse Red 1. -- Highlights: Black-Right-Pointing-Pointer Aqueous solutions of Disperse Red 1 were treated with chlorine. Black-Right-Pointing-Pointer The chlorination products of Disperse Red 1 were identified using LC-ESI-MS/MS. Black-Right-Pointing-Pointer Daphnia and Salmonella/microsome were employed for eco/genotoxicity testing. Black-Right-Pointing-Pointer The chlorinated dye was more mutagenic

Optimization of AZO films prepared on flexible substrates

Indian Academy of Sciences (India)

Administrator

grey relational analysis, the optimization of these deposition process parameters for AZO thin films with multiple characteristics ... bias voltage, annealing temperature and plasma treatment deposition time (Pei et ... water and dried in nitrogen.

Transparent conducting AZO and ITO films produced by pulsed laser ablation at 355 nm

DEFF Research Database (Denmark)

Thestrup, B.; Schou, Jørgen

1999-01-01

Thin films of aluminium-doped zinc oxide (AZO) and indium tin oxide (ITO) were deposited on glass substrates by laser ablation in an oxygen environment. The electrical and optical properties of films grown at various oxygen pressures were compared. With no substrate heating, highly transparent...... and conducting films were obtained with oxygen pressures between 15 and 23 mTorr for both materials. We obtained a specific resistivity of 1.8 x 10(-3) Omega cm for AZO and 1.1 x 10(-3) Omega cm for ITO. By heating the substrate to 160 degrees C or 200 degrees C, the resistivity was further reduced to 1.1 x 10......(-3) Omega cm for AZO and 3.9 x 10(-4) Omega cm for ITO. The average transmission of visible light (450-750 MI) was between 82% and 98% in most cases. The results suggest that AZO is a promising alternative to ITO....

Computational models for structure-hydrophobicity relationships of 4-carboxyl-2,6-dinitrophenyl azo hydroxynaphthalenes.

Science.gov (United States)

Idowu, Olakunle S; Adegoke, Olajire A; Idowu, Abiola; Olaniyi, Ajibola A

2007-01-01

Some phenyl azo hydroxynaphthalene dyes (e.g., sunset yellow) are certified as approved colorants for food, cosmetics, and drug formulations. The hydrophobicity of 4 newly synthesized azo dyes of the phenyl azo hydroxynaphthalene class was investigated, as a training set, with the goal of developing models for quantitative structure-property relationships (QSPR). Retention behavior of the molecules reversed-phase thin-layer chromatography (RPTLC) was investigated using liquid paraffin-coated silica gel as the stationary phase. Mobile phases consisted of aqueous mixtures of methanol, acetone, and dimethylformamide (DMF). Basic hydrophobicity parameter (Rmw), specific hydrophobic surface area (S), and isocratic chromatographic hydrophobicity index (phio) were computed from the chromatographic data. The hydrophobicity index (Rm) decreased linearly with increasing concentration of organic modifiers. Extrapolated Rmw values obtained by using DMF and acetone differ significantly from the value obtained by using methanol as organic modifier [P dyes and may also play useful roles in computer-assisted molecular discovery of nontoxic azo dyes.

Influence of various thickness metallic interlayers on opto-electric and mechanical properties of AZO thin films on PET substrates

Science.gov (United States)

Chang, R. C.; Li, T. C.; Lin, C. W.

2012-02-01

Various thickness metallic interlayers to improve the opto-electric and mechanical properties of aluminum-doped zinc oxide (AZO) thin films deposited on flexible polyethylene terephtalate (PET) substrates are studied. The effects of the interlayers on the resistance and transmittance of the AZO thin films are discussed. The result shows that the metallic interlayers effectively improve the electric resistance but reduce the optical transmittance of the AZO thin films. These phenomena become more obvious as the interlayer thickness increases. However, the AZO with an aluminum interlayer still behaves an acceptable transmittance. Moreover, mechanical tests indicate that the aluminum interlayer increases the hardness and modulus, and reduce the residual stress of the AZO thin films. In contrast, the silver and copper interlayers decrease the AZO's mechanical properties. Comparing to those without any interlayer, the results show that the best interlayer is the 6 nm thick aluminum film.

Studies on Dyeing Performance of Novel Acid Azo Dyes and Mordent Acid Azo Dyes Based on 2,4-Dihydroxybenzophenone

Directory of Open Access Journals (Sweden)

Bharat C. Dixit

2009-01-01

Full Text Available Novel acid azo and mordent acid azo dyes have been prepared by the coupling of diazo solution of different aminonaphthol sulphonic acids and aromatic amino acids with 2,4-dihydroxybenzophenone. The resultant dyes were characterized by elemental analysis as well as IR and 1H NMR spectral studies. The UV-visible spectral data have also been discussed in terms of structure property relationship. The dyeing assessments of all the dyes were evaluated on wool and silk textile fibers. The dyeing of chrome pretreated wool and silk have also been monitored. The result shows that better hue was obtained on mordented fiber. Results of bactericidal studies of chrome pretreated fibers revealed that the toxicity of mordented dyes against bacteria is fairly good. Dyeing on wool and silk fibers resulted in yellowish pink to reddish brown colourations having excellent light fastness and washing fastness.

(azo anils and oxalate ion) copper(ii)

African Journals Online (AJOL)

B. S. Chandravanshi

transition metal complexes compared to corresponding free ligands may be attributed to structural symmetry of ... C H, N contents in synthesized azo anils ligands and in Cu(II) complexes were found using. CHNS technique (Costech international-4100). Metal contents in synthesized complexes were. Compounds. Color.

The in situ generation and reactive quench of diazonium compounds in the synthesis of azo compounds in microreactors.

Science.gov (United States)

Akwi, Faith M; Watts, Paul

2016-01-01

In this paper, a micro-fluidic optimized process for the continuous flow synthesis of azo compounds is presented. The continuous flow synthesis of Sudan II azo dye was used as a model reaction for the study. At found optimal azo coupling reaction temperature and pH an investigation of the optimum flow rates of the reactants for the diazotization and azo coupling reactions in Little Things Factory-MS microreactors was performed. A conversion of 98% was achieved in approximately 2.4 minutes and a small library of azo compounds was thus generated under these reaction conditions from couplers with aminated or hydroxylated aromatic systems. The scaled up synthesis of these compounds in PTFE tubing (i.d. 1.5 mm) was also investigated, where good reaction conversions ranging between 66-91% were attained.

Preparation and morphological and optical characterization of azo-polymer-based SiO2 sonogel hybrid composites

International Nuclear Information System (INIS)

Morales-Saavedra, Omar G; Ontiveros-Barrera, Fernando G; Torres-Zúñiga, Vicente; Guadalupe-Bañuelos, José; Ortega-Martínez, Roberto; Rivera, Ernesto; García, Tonatiuh

2009-01-01

The well-established catalyst-free sonogel route was successfully implemented to fabricate highly pure, optically active, solid state polymeric azo- dye/SiO 2 -based hybrid composites. Bulk samples exhibit controllable geometrical shapes and monolithic structure with variable dopant concentrations. Since the implemented azo-dye chromophores exhibit a push–pull structure, hybrid film samples were spin-coated on ITO-covered glass substrates; molecular alignment was then performed via electrical poling in order to explore the quadratic nonlinear optical performance of this kind of composite. Comprehensive morphological, spectroscopic and optical characterization of the samples were performed with several experimental techniques: atomic force microscopy, x-ray diffraction and infrared, Raman, photoluminescent and ultraviolet–visible spectroscopies. The linear refractive indices of both bulk and thin film samples were measured according to the Brewster angle technique and a numerical analysis of the transmission spectral data, respectively. Regardless of the low glass transition temperatures of the studied polymers, some hybrid film samples were able to display stable nonlinear optical activity such as second harmonic generation. Results show that the chromophores were satisfactorily embedded into the highly pure SiO 2 sonogel network without significant guest–host molecular interactions, thus preserving their optical properties and producing sol–gel hybrid glasses suitable for optical applications

Effect of dye structure and redox mediators on anaerobic azo and anthraquinone dye reduction

Directory of Open Access Journals (Sweden)

Mayara Carantino Costa

2012-01-01

Full Text Available We investigated the biological decolourisation of dyes with different molecular structures. The kinetic constant values (k1 achieved with azo dye Reactive Red 120 were 7.6 and 10.1 times higher in the presence of RM (redox mediators AQDS and riboflavin, respectively, than the assays lacking RM. The kinetic constant achieved with the azo dye Congo Red was 42 times higher than that obtained with the anthraquinone dye Reactive Blue 4. The effect of RM on dye reduction was more evident for azo dyes resistant to reductive processes, and ineffective for anthraquinone dyes because of the structural stability of the latter.

Acid azo dye remediation in anoxic-aerobic-anoxic microenvironment under periodic discontinuous batch operation: bio-electro kinetics and microbial inventory.

Science.gov (United States)

Venkata Mohan, S; Suresh Babu, P; Naresh, K; Velvizhi, G; Madamwar, Datta

2012-09-01

Functional behavior of anoxic-aerobic-anoxic microenvironment on azo dye (C.I. Acid black 10B) degradation was evaluated in a periodic discontinuous batch mode operation for 26 cycles. Dye removal efficiency and azo-reductase activity (30.50 ± 1 U) increased with each feeding event until 13th cycle and further stabilized. Dehydrogenase activity also increased gradually and stabilized (2.0 ± 0.2 μg/ml) indicating the stable proton shuttling between metabolic intermediates providing higher number of reducing equivalents towards dye degradation. Voltammetric profiles showed drop in redox catalytic currents during stabilized phase also supports the consumption of reducing equivalents towards dye removal. Change in Tafel slopes, polarization resistance and other bioprocess parameters correlated well with the observed dye removal and biocatalyst behavior. Microbial community analysis documented the involvement of specific organism pertaining to aerobic and facultative functions with heterotrophic and autotrophic metabolism. Integrating anoxic microenvironment with aerobic operation might have facilitated effective dye mineralization due to the possibility of combining redox functions. Copyright © 2012 Elsevier Ltd. All rights reserved.

Acetylcholinesterase Inhibition and Antioxidant Activity of N-trans-Caffeoyldopamine and N-trans-Feruloyldopamine

Directory of Open Access Journals (Sweden)

Muamer Dizdar

2018-04-01

Full Text Available Phenolic acids and their derivatives found in nature are well-known for their potential biological activity. In this study, two amides derived from trans-caffeic/ferulic acid and dopamine were synthesized and characterized by Fourier-transform infrared spectroscopy (FTIR, mass spectrometry, proton and carbon-13 nuclear magnetic resonance spectroscopy. The compounds were tested for the inhibition of acetylcholinesterase (AChE from Electrophorus electricus and for antioxidant activity by scavenging 2,2-diphenyl-1-pycrylhydrazyl free radical (DPPH• and 2,2′-azinobis(3-ethylbenzothiazoline-6-sulphonic acid radical cation (ABTS•+, reducing ferric ions, and ferrous ions chelation. N-trans-Feruloyldopamine displayed the highest inhibitory effect on AChE with half-maximal inhibitory concentration (IC50 values of 8.52 μM. In addition, an in silico study was done to determine the most favorable AChE cluster with the synthesized compounds. Further, these clusters were investigated for binding positions at the lowest free binding energy. Both synthesized hydroxycinnamates were found to be better antioxidants than the parent acids in in vitro tests applied. N-trans-Caffeoyldopamine showed the best antioxidant activity in the three tested methods—against non-biological stable free radicals IC50 5.95 μM for DPPH•, 0.24 μM for the ABTS•+ method, and for reducing power (ascorbic acid equivalent (AAE 822.45 μmol/mmol—while for chelation activity against Fe2+ ions N-trans-feruloyldopamine had slightly better antioxidant activity (IC50 3.17 mM.

The in situ generation and reactive quench of diazonium compounds in the synthesis of azo compounds in microreactors

Directory of Open Access Journals (Sweden)

Faith M. Akwi

2016-09-01

Full Text Available In this paper, a micro-fluidic optimized process for the continuous flow synthesis of azo compounds is presented. The continuous flow synthesis of Sudan II azo dye was used as a model reaction for the study. At found optimal azo coupling reaction temperature and pH an investigation of the optimum flow rates of the reactants for the diazotization and azo coupling reactions in Little Things Factory-MS microreactors was performed. A conversion of 98% was achieved in approximately 2.4 minutes and a small library of azo compounds was thus generated under these reaction conditions from couplers with aminated or hydroxylated aromatic systems. The scaled up synthesis of these compounds in PTFE tubing (i.d. 1.5 mm was also investigated, where good reaction conversions ranging between 66–91% were attained.

Electroluminescence enhancement for near-ultraviolet light emitting diodes with graphene/AZO-based current spreading layers

DEFF Research Database (Denmark)

Lin, Li; Ou, Yiyu; Zhu, Xiaolong

LEDs) have attracted significant research interest due to their intensive applications in various areas where indium tin oxide (ITO) is one of the most widely employed transparent conductive materials for NUV LEDs. Compared to ITO, indium-free aluminum-doped zinc oxide (AZO) has similar electrical......Near-ultraviolet light emitting diodes with different aluminum-doped zinc oxide-based current spreading layers were fabricated and electroluminescence (EL) was compared. A 170% EL enhancement was achieved by using a graphene-based interlayer. GaN-based near-ultraviolet light emitting diodes (NUV...... with a new type of current spreading layer (CSL) which combines AZO and a single-layer graphene (SLG) as an effective transparent CSL [1]. In the present work, LEDs with solo AZO CSL in Fig.1(a) and SLG/Ni/AZO-based CSL in Fig.1(b) were both fabricated for EL comparison. Standard mesa fabrication including...

Use of Titanium Dioxide Photocatalysis on the Remediation of Model Textile Wastewaters Containing Azo Dyes

Directory of Open Access Journals (Sweden)

Josino Costa Moreira

2011-12-01

Full Text Available The photocatalytic degradation of two commercial textile azo dyes, namely C.I Reactive Black 5 and C.I Reactive Red 239, has been studied. TiO2 P25 Degussa was used as catalyst and photodegradation was carried out in aqueous solution under artificial irradiation with a 125 W mercury vapor lamp. The effects of the amount of TiO2 used, UV-light irradiation time, pH of the solution under treatment, initial concentration of the azo dye and addition of different concentrations of hydrogen peroxide were investigated. The effect of the simultaneous photodegradation of the two azo dyes was also investigated and we observed that the degradation rates achieved in mono and bi-component systems were identical. The repeatability of photocatalytic activity of the photocatalyst was also tested. After five cycles of TiO2 reuse the rate of colour lost was still 77% of the initial rate. The degradation was followed monitoring the change of azo dye concentration by UV-Vis spectroscopy. Results show that the use of an efficient photocatalyst and the adequate selection of optimal operational parameters may easily lead to a complete decolorization of the aqueous solutions of both azo dyes.

Azo compound degradation kinetics and halonitromethane formation kinetics during chlorination.

Science.gov (United States)

Fu, Jing; Wang, Xiaomao; Bai, Weiliang; Yang, Hongwei; Xie, Yuefeng F

2017-05-01

The chlorination of azo compounds can produce halonitromethanes (HNMs), which have attracted increasing concern due to their high genotoxicity. By impacting the speciation of chlorine and azo compounds, pH impacts apparent second-order rate constants of Methyl Orange (MO, 27.5-1.4 × 10 3  M -1  s -1 ), Acid Orange II (AO, 16.7-99.3 M -1  s -1 ), and Acid Red 1 (AR 1, 3.7-72.5 M -1  s -1 ) (pH range 6.3-9.0). The two-compartment first-order model successfully described the chloropicrin (TCNM) formation kinetics, suggesting that both fast- and slow-reacting precursors of TCNM are generated from the chlorination of azo compounds. The ratios between fast and slow formation rate constants for MO and AO were 15.6-5.4 × 10 2 , while that of AR 1 was 9.8-19.4 (pH range 6.5-9.0). The fraction of the fast-reacting TCNM precursors decreased with increasing pH for MO and AO; while that for AR 1 decreased when pH increased from 6.5 to 8.0, and then increased when pH increased from 8.0 to 9.0. The impact of pH on TCNM formation was also precursor-specific. The highest molar yields of TCNM predicted from the model in this study were 2.4%, 2.5%, and 1.5% for MO, AO, and AR 1, respectively. The study demonstrates that azo compounds are important HNM precursors, and pose a potential threat to drinking water safety. Copyright © 2017 Elsevier Ltd. All rights reserved.

Comparative study on reaction selectivity of azo dye decolorization by Pseudomonas luteola

International Nuclear Information System (INIS)

Hsueh, C.-C.; Chen, B.-Y.

2007-01-01

This study is to inspect how the variation of molecular structures and functional groups present in our model azo dyes (i.e., Congo red, Eriochrome black T (EBT), methyl orange, and methyl red) affects biodecolorization capability of Pseudomonas luteola. The most viable decolorization was found at pH 7-9 and the optimal cellular age for the most effective decolorization was 7 days after static incubation in dye-free cultures. In decolorization, the maximal absorption wavelength in UV-vis spectra for the different dye-containing cultures shifted from visible light range towards the ultraviolet visible range. Methyl red was not decolorized in contrast to methyl orange, Congo red, and Eriochrome black T. The sulfonic group para to azo bond (-N=N-) in methyl orange was a strong electron-withdrawing group through resonance to cause an enhancement of color removal to be easily biodecolorized. As a charged carboxyl group on methyl red is at ortho position (i.e., in the proximity) to azo bond, this led to a complete inhibition to decolorization. However, decolorization of Congo red and EBT in the absence of charged group (e.g., hydroxy or amino group) near azo bond was not completely repressed like methyl red. Thus, the presence of electron-withdrawing groups as the substituents on azo dyes enhanced decolorization capability for biodegradability. In addition, Monod kinetic model provided better predictions to all dye decolorization at initial short periods of time due to negligible intermediate formed at initial short time duration, but significant intermediate accumulation took place at longer period of time. In contrast, the decolorization performances of methyl orange at 400 ppm and EBT at 230 ppm were significantly less than those predicted from the Monod kinetic model likely due to accumulated intermediates exceeding the threshold levels for feedback inhibition

Effect of silver nanoparticles on photo-induced reorientation of azo groups in polymer films

International Nuclear Information System (INIS)

Zhou Jingli; Yang Jianjun; Sun Youyi; Zhang Douguo; Shen Jing; Zhang Qijin; Wang Keyi

2007-01-01

A series of polymer films containing azo groups and silver nanoparticles were prepared. Photo-induced reorientation of the film was conducted under irradiation of polarized light with wavelength at 365 nm, 442 nm and 532 nm, respectively. The influence of the concentration of dopant silver on the reorientation of the azo groups was studied. An enhancement of about 50% for the reorientation rate and about 70% for the reorientation amplitude was achieved. From a comparison of the enhancement obtained by irradiating with three different light sources, it was realized that the mechanism for enhancement of reorientation of azo groups is due to plasmon resonance of silver nanoparticles doped in the polymer films

Impact of self-assembled monolayer assisted surface dipole modulation of PET substrate on the quality of RF-sputtered AZO film

Energy Technology Data Exchange (ETDEWEB)

Vo, Thieu Thi Tien [Department of Chemical Engineering, National Taiwan University of Science and Technology, Taipei 10607, Taiwan (China); Faculty of Chemical Engineering and Food Technology, Ba Ria-Vung Tau University, Vung Tau (Viet Nam); Mahesh, K.P.O. [Department of Chemical Engineering, National Taiwan University of Science and Technology, Taipei 10607, Taiwan (China); Lin, Pao-Hung [Department of Electronic and Computer Engineering, National Taiwan University of Science and Technology, Taipei 10607, Taiwan (China); Tai, Yian, E-mail: ytai@mail.ntust.edu.tw [Department of Chemical Engineering, National Taiwan University of Science and Technology, Taipei 10607, Taiwan (China)

2017-05-01

Highlights: • We use SAMs functionalizing the PET substrates to generate different surface dipoles. • We deposited AZO film on pristine and SAMs-modified PET substrate. • The positive dipole moment of PET surface promotes the crystallinity of AZO film. • The negative dipole moment of PET surface deteriorates the crystallinity of AZO film. • The electrical properties of AZO/PET changes upon the variation of the crystallinity. - Abstract: In this study, we fabricated the electron donating/withdrawing group functionalized organosilane self-assembled monolayers (SAMs) on transparent polyethylene terephthalate (PET) flexible substrate followed by the deposition of aluminum doped zinc oxide (AZO) using RF magnetron sputtering at room temperature. The effect of different SAMs on transparent PET substrates and AZO films were studied by contact angle (CA), X-ray photoelectron spectroscopy (XPS), Atomic force microscopy (AFM), X-ray diffraction (XRD), Field-Emission scanning electron microscope (FE-SEM), Hall measurement and UV–vis spectroscopy (UV–vis). The results presented that the surface dipole (i.e. electron-donating/withdrawing) of different SAMs functionalized PET substrates affected the quality of the AZO films which deposited on top of them. The crystallinity, the charge mobility, and the carrier concentration of the AZO improved when the film was deposited on the PET functionalized with electron donating group, which was possibly due to favored interaction between electron donating group and Al ions.

Impact of self-assembled monolayer assisted surface dipole modulation of PET substrate on the quality of RF-sputtered AZO film

International Nuclear Information System (INIS)

Vo, Thieu Thi Tien; Mahesh, K.P.O.; Lin, Pao-Hung; Tai, Yian

2017-01-01

Highlights: • We use SAMs functionalizing the PET substrates to generate different surface dipoles. • We deposited AZO film on pristine and SAMs-modified PET substrate. • The positive dipole moment of PET surface promotes the crystallinity of AZO film. • The negative dipole moment of PET surface deteriorates the crystallinity of AZO film. • The electrical properties of AZO/PET changes upon the variation of the crystallinity. - Abstract: In this study, we fabricated the electron donating/withdrawing group functionalized organosilane self-assembled monolayers (SAMs) on transparent polyethylene terephthalate (PET) flexible substrate followed by the deposition of aluminum doped zinc oxide (AZO) using RF magnetron sputtering at room temperature. The effect of different SAMs on transparent PET substrates and AZO films were studied by contact angle (CA), X-ray photoelectron spectroscopy (XPS), Atomic force microscopy (AFM), X-ray diffraction (XRD), Field-Emission scanning electron microscope (FE-SEM), Hall measurement and UV–vis spectroscopy (UV–vis). The results presented that the surface dipole (i.e. electron-donating/withdrawing) of different SAMs functionalized PET substrates affected the quality of the AZO films which deposited on top of them. The crystallinity, the charge mobility, and the carrier concentration of the AZO improved when the film was deposited on the PET functionalized with electron donating group, which was possibly due to favored interaction between electron donating group and Al ions.

Using chemical wet-etching methods of textured AZO films on a-Si:H solar cells for efficient light trapping

Energy Technology Data Exchange (ETDEWEB)

Lin, Guo-Sheng; Li, Chien-Yu; Huang, Kuo-Chan; Houng, Mau-Phon, E-mail: mphoung@eembox.ncku.edu.tw

2015-06-15

In this paper, Al-doped ZnO (AZO) films are deposited on glasses substrate by RF magnetron sputtering. The optical, electrical and morphological properties of AZO films textured by wet-etching with different etchants, H{sub 3}PO{sub 4}, HCl, and HNO{sub 3} are studied. It is found that the textured structure could enhance the light scattering and light trapping ability of amorphous silicon solar cells. The textured AZO film etched with HNO{sub 3} exhibits optimized optical properties (T% ≧ 80% over entire wavelength, haze ratio > 40% at 550 nm wavelength) and excellent electrical properties (ρ = 5.86 × 10{sup −4} Ωcm). Scanning electron microscopy and Atomic force microscopy are used to observe surface morphology and average roughness of each textured AZO films. Finally, the textured AZO films etched by H{sub 3}PO{sub 4}, HCl and HNO{sub 3} were applied to front electrode layer for p–i–n amorphous silicon solar cells. The highest conversion efficiency of amorphous silicon solar cell fabricated on HNO{sub 3}-etched AZO film was 7.08% with open-circuit voltage, short-circuit current density and fill factor of 895 mV, 14.92 mA/cm{sup 2} and 0.56, respectively. It shows a significantly enhancement in the short-circuit current density and conversion efficiency by 16.2% and 20.2%, respectively, compared with the solar cell fabricated on as-grown AZO film. - Highlights: • The textured surface enhances light scattering and light trapping ability. • The HNO{sub 3}-etched AZO film exhibits excellent optical and electrical properties. • The efficiency of a-Si:H solar cell fabricated on HNO{sub 3}-etched AZO film was 7.08%. • The short-circuit current density enhances to 16.2%. • The conversion efficiency enhances to 20.2%.

Using chemical wet-etching methods of textured AZO films on a-Si:H solar cells for efficient light trapping

International Nuclear Information System (INIS)

Lin, Guo-Sheng; Li, Chien-Yu; Huang, Kuo-Chan; Houng, Mau-Phon

2015-01-01

In this paper, Al-doped ZnO (AZO) films are deposited on glasses substrate by RF magnetron sputtering. The optical, electrical and morphological properties of AZO films textured by wet-etching with different etchants, H 3 PO 4 , HCl, and HNO 3 are studied. It is found that the textured structure could enhance the light scattering and light trapping ability of amorphous silicon solar cells. The textured AZO film etched with HNO 3 exhibits optimized optical properties (T% ≧ 80% over entire wavelength, haze ratio > 40% at 550 nm wavelength) and excellent electrical properties (ρ = 5.86 × 10 −4 Ωcm). Scanning electron microscopy and Atomic force microscopy are used to observe surface morphology and average roughness of each textured AZO films. Finally, the textured AZO films etched by H 3 PO 4 , HCl and HNO 3 were applied to front electrode layer for p–i–n amorphous silicon solar cells. The highest conversion efficiency of amorphous silicon solar cell fabricated on HNO 3 -etched AZO film was 7.08% with open-circuit voltage, short-circuit current density and fill factor of 895 mV, 14.92 mA/cm 2 and 0.56, respectively. It shows a significantly enhancement in the short-circuit current density and conversion efficiency by 16.2% and 20.2%, respectively, compared with the solar cell fabricated on as-grown AZO film. - Highlights: • The textured surface enhances light scattering and light trapping ability. • The HNO 3 -etched AZO film exhibits excellent optical and electrical properties. • The efficiency of a-Si:H solar cell fabricated on HNO 3 -etched AZO film was 7.08%. • The short-circuit current density enhances to 16.2%. • The conversion efficiency enhances to 20.2%

Effect of Reactive Black 5 azo dye on soil processes related to C and N cycling

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Khadeeja Rehman

2018-05-01

Full Text Available Azo dyes are one of the largest classes of synthetic dyes being used in textile industries. It has been reported that 15–50% of these dyes find their way into wastewater that is often used for irrigation purpose in developing countries. The effect of azo dyes contamination on soil nitrogen (N has been studied previously. However, how does the azo dye contamination affect soil carbon (C cycling is unknown. Therefore, we assessed the effect of azo dye contamination (Reactive Black 5, 30 mg kg−1 dry soil, bacteria that decolorize this dye and dye + bacteria in the presence or absence of maize leaf litter on soil respiration, soil inorganic N and microbial biomass. We found that dye contamination did not induce any change in soil respiration, soil microbial biomass or soil inorganic N availability (P > 0.05. Litter evidently increased soil respiration. Our study concludes that the Reactive Black 5 azo dye (applied in low amount, i.e., 30 mg kg−1 dry soil contamination did not modify organic matter decomposition, N mineralization and microbial biomass in a silty loam soil.

Decolorization of azo dyes (Direct Blue 151 and Direct Red 31 by moderately alkaliphilic bacterial consortium

Directory of Open Access Journals (Sweden)

Sylvine Lalnunhlimi

2016-03-01

Full Text Available Abstract Removal of synthetic dyes is one of the main challenges before releasing the wastes discharged by textile industries. Biodegradation of azo dyes by alkaliphilic bacterial consortium is one of the environmental-friendly methods used for the removal of dyes from textile effluents. Hence, this study presents isolation of a bacterial consortium from soil samples of saline environment and its use for the decolorization of azo dyes, Direct Blue 151 (DB 151 and Direct Red 31 (DR 31. The decolorization of azo dyes was studied at various concentrations (100–300 mg/L. The bacterial consortium, when subjected to an application of 200 mg/L of the dyes, decolorized DB 151 and DR 31 by 97.57% and 95.25% respectively, within 5 days. The growth of the bacterial consortium was optimized with pH, temperature, and carbon and nitrogen sources; and decolorization of azo dyes was analyzed. In this study, the decolorization efficiency of mixed dyes was improved with yeast extract and sucrose, which were used as nitrogen and carbon sources, respectively. Such an alkaliphilic bacterial consortium can be used in the removal of azo dyes from contaminated saline environment.

Novel bio-electro-Fenton technology for azo dye wastewater treatment using microbial reverse-electrodialysis electrolysis cell

DEFF Research Database (Denmark)

Li, Xiaohu; Jin, Xiangdan; Zhao, Nannan

2017-01-01

Development of sustanaible technologies for treatment of azo dyes containing wastewaters has long been of great interest. In this study, we proposed an innovative concept of using microbial reverse-electrodialysis electrolysis cell (MREC) based Fenton process to treat azo dye wastewater. In such ......Development of sustanaible technologies for treatment of azo dyes containing wastewaters has long been of great interest. In this study, we proposed an innovative concept of using microbial reverse-electrodialysis electrolysis cell (MREC) based Fenton process to treat azo dye wastewater....... In such MREC-Fenton integrated process, the production of H2O2 which is the key reactant of fenton-reaction was driven by the electrons harvested from the exoelectrogens and salinity-gradient between sea water and fresh water in MREC. Complete decolorization and mineralization of 400 mg L-1 Orange G...

Photocontrol of Voltage-Gated Ion Channel Activity by Azobenzene Trimethylammonium Bromide in Neonatal Rat Cardiomyocytes.

Directory of Open Access Journals (Sweden)

Sheyda R Frolova

Full Text Available The ability of azobenzene trimethylammonium bromide (azoTAB to sensitize cardiac tissue excitability to light was recently reported. The dark, thermally relaxed trans- isomer of azoTAB suppressed spontaneous activity and excitation propagation speed, whereas the cis- isomer had no detectable effect on the electrical properties of cardiomyocyte monolayers. As the membrane potential of cardiac cells is mainly controlled by activity of voltage-gated ion channels, this study examined whether the sensitization effect of azoTAB was exerted primarily via the modulation of voltage-gated ion channel activity. The effects of trans- and cis- isomers of azoTAB on voltage-dependent sodium (INav, calcium (ICav, and potassium (IKv currents in isolated neonatal rat cardiomyocytes were investigated using the whole-cell patch-clamp technique. The experiments showed that azoTAB modulated ion currents, causing suppression of sodium (Na+ and calcium (Ca2+ currents and potentiation of net potassium (K+ currents. This finding confirms that azoTAB-effect on cardiac tissue excitability do indeed result from modulation of voltage-gated ion channels responsible for action potential.

Novel colorimetric sensors for cyanide based on azo-hydrazone tautomeric skeletons.

Science.gov (United States)

Adegoke, Olajire A; Adesuji, Temitope E; Thomas, Olusegun E

2014-07-15

The monoazo dyes, 4-carboxyl-2, 6-dinitrophenylazohydroxynaphthalenes dyes (AZ-01, AZ-03 and AZ-04), were evaluated as a highly selective colorimetric chemosensor for cyanide ion. The recognition of cyanide ion gave an obvious colour change from light yellow to brownish red and upon dilution with acetone produced a purple to lilac colour. Optimum conditions for the reaction between the azo dyes and cyanide ion were established at 30°C for 5 min, and different variables affecting the reaction were carefully studied and optimised. Under the optimum conditions, linear relationships between the CN(-) concentrations and light absorption were established. Using these azo-hydrazone molecular switch entities, excellent selectivity towards the detection of CN(-) in aqueous solution over miscellaneous competitive anions was observed. Such selectivity mainly results from the possibility of nucleophilic attack on the azo-hydrazone chemosensors by cyanide anions in aqueous system, which is not afforded by other competing anions. The cyanide chemosensor method described here should have potential application as a new family probes for detecting cyanide in aqueous solution. Copyright © 2014 Elsevier B.V. All rights reserved.

ADSORPSI-DESORPSI ZAT WARNA AZO JENIS REMAZOL BLACK B MENGGUNAKAN MEMBRAN POLIELEKTROLIT (PEC KITOSAN-PEKTIN

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Ni Putu Sri Ayuni

2016-08-01

Full Text Available Abstrak Sekitar 2-50% dari zat warna azo yang digunakan selama proses pencelupan ini tidak mengikat serat dan langsung dilepaskan ke lingkungan melalui instalasi pengolahan limbah. Hal ini perlu dilakukan pengolahan limbah cair yang mengandung zat warna azo jenis Remazol Black B sebelum dibuang ke lingkungan. Penelitian ini bertujuan untuk mengetahui kondisi optimum membran PEC kitosan-pektin yang dapat digunakan untuk mengadsorpsi zat warna azo jenis Remazol Black B .Untuk memperoleh kondisi optimum akan dilakukan adsorpsi zat warna azo jenis Remazol Black B dengan variasi waktu kontak (5-150 menit, pH (5-9 dan konsentrasi larutan zat warna azo jenis Remazol Black B (5, 10, 15, 20, dan 25 mg/L. Untuk mengetahui karakteristik zat warna jenis Remazol Black B oleh membran PEC kitosan-pektin di analisis dengan persamaan isoterm adsorpsi Langmuir dan isoterm adsorpsi Freundlich sedangkan daya adsorpsi maksimum dari membran PEC kitosan pektin ditentukan dari kurva berdasarkan karakteristik membran yang diperoleh. Hasil penelitian menunjukkan bahwa adsorpsi zat warna azo jenis Remazol Black B terjadi pada kondisi optimum dengan pH 5, waktu 120 menit dan konsentrasi larutan zat warna azo jenis Remazol Black B 10 mg/L (62,75 %. Pola adsorpsi mengikuti pola adsorpsi isoterm Freundlich dengan daya adsorpsi maksimum 0,02 (mg/g. Untuk efisiensi desorpsi maksimal diperoleh pada larutan NaCl 1 M (11,17 % Kata Kunci: adsorpsi, membran polielektrolit kitosan pektin, Remazol Black B Abstract Azo dyes produced approximately 2-50% from dying process were thrown through effluent to the environment without any treatment. The objective of this research were to know the optimum condition of PEC chitosan pectin membrane using to adsorp Remazol Black B with various contact time (5-150 min, pH (5-9 and Remazol Black B concentration (5, 10, 15, 20, dan 25 mg/L. Adsorption charactheristic of Remazol Black B by PEC chitosan pectin membrane were determined by Langmuir and

Atomic-Layer-Deposited AZO Outperforms ITO in High-Efficiency Polymer Solar Cells

KAUST Repository

Kan, Zhipeng

2018-05-11

Tin-doped indium oxide (ITO) transparent conducting electrodes are widely used across the display industry, and are currently the cornerstone of photovoltaic device developments, taking a substantial share in the manufacturing cost of large-area modules. However, cost and supply considerations are set to limit the extensive use of indium for optoelectronic device applications and, in turn, alternative transparent conducting oxide (TCO) materials are required. In this report, we show that aluminum-doped zinc oxide (AZO) thin films grown by atomic layer deposition (ALD) are sufficiently conductive and transparent to outperform ITO as the cathode in inverted polymer solar cells. Reference polymer solar cells made with atomic-layer-deposited AZO cathodes, PCE10 as the polymer donor and PC71BM as the fullerene acceptor (model systems), reach power conversion efficiencies of ca. 10% (compared to ca. 9% with ITO-coated glass), without compromising other figures of merit. These ALD-grown AZO electrodes are promising for a wide range of optoelectronic device applications relying on TCOs.

Atomic-Layer-Deposited AZO Outperforms ITO in High-Efficiency Polymer Solar Cells

KAUST Repository

Kan, Zhipeng; Wang, Zhenwei; Firdaus, Yuliar; Babics, Maxime; Alshareef, Husam N.; Beaujuge, Pierre

2018-01-01

Tin-doped indium oxide (ITO) transparent conducting electrodes are widely used across the display industry, and are currently the cornerstone of photovoltaic device developments, taking a substantial share in the manufacturing cost of large-area modules. However, cost and supply considerations are set to limit the extensive use of indium for optoelectronic device applications and, in turn, alternative transparent conducting oxide (TCO) materials are required. In this report, we show that aluminum-doped zinc oxide (AZO) thin films grown by atomic layer deposition (ALD) are sufficiently conductive and transparent to outperform ITO as the cathode in inverted polymer solar cells. Reference polymer solar cells made with atomic-layer-deposited AZO cathodes, PCE10 as the polymer donor and PC71BM as the fullerene acceptor (model systems), reach power conversion efficiencies of ca. 10% (compared to ca. 9% with ITO-coated glass), without compromising other figures of merit. These ALD-grown AZO electrodes are promising for a wide range of optoelectronic device applications relying on TCOs.

Solar photoassisted advanced oxidation process of azo dyes.

Science.gov (United States)

Prato-Garcia, D; Buitrón, G

2009-01-01

Advanced oxidation processes assisted with natural solar radiation in CPC type reactors (parabolic collector compound), was applied for the degradation of three azo dyes: acid orange (AO7), acid red 151 (AR151) and acid blue 113 (AB113). Fenton, Fenton like and ferrioxalate-type complexes showed to be effective for degrade the azo linkage and moieties in different extensions. Initially, the best dose of reagents (Fe(3 + )-H(2)O(2)) was determined through a factorial experimental design, next, using response surface methodologies, the reagent consumption was reduced up to 40%, maintaining in all cases high decolourisation percentages (>98%) after 60 min. of phototreatment. In this work, it was also studied the effect of concentration changes of the influent between 100-300 mg/L and the operation of the photocatalytic process near neutral conditions (pH 6.0-6.5) by using ferrioxalate type complex (FeOx).

TiO2/beads as a photocatalyst for the degradation of X3B azo dye

Institute of Scientific and Technical Information of China (English)

无

2003-01-01

The feasibility of photocatalytic degradation of X3B azo dye by TiO2/beads photocatalyst was studied. The effects of parameters such as the amount of TiO2/beads, airflow, as well as the concentrations of H2O2, Fe3+, Mg2+ and Na+ on the photocatalytic degradation of X3B azo dye were also studied. The results showed that 25 mg/dm3 X3B azo dye can be photocatalytically degraded completely by 30 min illumination with a 375W medium pressure mercury lamp. Adding a small amount of H2O2 or Fe3+, the efficiencies of photocatalytic degradation of X3B azo dye were increased rapidly. The mechanisms of the reaction and the role of the additives were also investigated. After 120 hours TiO2/beads showed no significant loss of the photocatalytic activity.

Ozonation of azo dyes (Orange II and Acid Red 27) in saline media

International Nuclear Information System (INIS)

Silva, Alessandra C.; Pic, Jean Stephane; Sant'Anna, Geraldo L.; Dezotti, Marcia

2009-01-01

Ozonation of two azo dyes was investigated in a monitored bench scale bubble column reactor (8.5-L), varying liquid media salt content (0, 1, 40 and 100 g L -1 , NaCl). In experiments with Orange II pH was varied (5, 7.5 and 9) but ozonation of Acid Red 27 was performed at pH 7.5. Ozone self-decomposition rate-constant increased with salt concentration. Color removal was very effective and fast achieved under all experimental conditions. For the two azo dyes tested, more than 98% of color intensity was removed in 30-min ozonation assays. However, only partial mineralization of azo dyes (45%-Orange II; 20%-Acid Red 27) was attained in such experiments. The degree of mineralization (TOC removal) was negatively affected by salt concentration. Biodegradation assays conducted by respirometry revealed the inhibitory effect of dye degradation products formed during ozonation.

Methods for the analysis of azo dyes employed in food industry--A review.

Science.gov (United States)

Yamjala, Karthik; Nainar, Meyyanathan Subramania; Ramisetti, Nageswara Rao

2016-02-01

A wide variety of azo dyes are generally added for coloring food products not only to make them visually aesthetic but also to reinstate the original appearance lost during the production process. However, many countries in the world have banned the use of most of the azo dyes in food and their usage is highly regulated by domestic and export food supplies. The regulatory authorities and food analysts adopt highly sensitive and selective analytical methods for monitoring as well as assuring the quality and safety of food products. The present manuscript presents a comprehensive review of various analytical techniques used in the analysis of azo dyes employed in food industries of different parts of the world. A brief description on the use of different extraction methods such as liquid-liquid, solid phase and membrane extraction has also been presented. Copyright © 2015 Elsevier Ltd. All rights reserved.

Triphenyl{(E-4-[4-(phenyldiazenylphenyl]-4H-1,2,4-triazol-1-yl}boron

Directory of Open Access Journals (Sweden)

Daisuke Urakami

2009-10-01

Full Text Available In the title compound, C32H26BN5 or [(C14H11N5B(C6H53], the B atom is approximately tetrahedrally coordinated. The diazo unit is in a trans conformation, which is generally more stable than a cis one for aromatic azo compounds. The crystal structure features very weak C—H...π interactions. The dihedral angles between the central benzene ring and the terminal rings in the heterocycle are 62.64, 73.54 and 61.60°.

Role of brown-rot fungi in the bioremoval of azo dyes under different conditions

Directory of Open Access Journals (Sweden)

Naeem Ali

2010-12-01

Full Text Available The present study is vital to the understanding of bioremediation of structurally different azo dyes by some unusual Brown-rot fungi. Bioremoval of each dye (20 mg l-1 was tested in two different culture media under static and shaking conditions by taking inocula from different fungi. Fungal strains showed varying dyes removal abilities, though considerable high in case of Acid Red (AR 151(di-azo as compared to Orange (Or II (mono-azo. With an exception of Aspergillus tereus SA3, all the fungal isolates showed higher removal of dyes in SDB. Under static condition, the maximum decolorizing fungal strains were; Aspergillus flavus SA2 (67% and Alternaria spp. SA4 (57% in AR 151, while Penicillium spp. (34 and 33 % in Orange II, in SDB and STE, respectively. Bioremoval of dyes was considerably increased when experiments were shifted from static to shaking mode. It was specifically increased (% in; AR 151 (255 with Penicillium spp., Or II with A. flavus SA2 (112 and Alternaria spp. (111. The primary mechanism of dyes removal proved to be fungal biosorption. However, reduction of dyes (onto fungal with formation of their products (α. naphthol, sulphalinic acid and aniline furthermore revealed that dyes (specifically azo were actually biodegraded.

Microbial dynamics during azo dye degradation in a UASB reactor supplied with yeast extract.

Science.gov (United States)

Silva, S Q; Silva, D C; Lanna, M C S; Baeta, B E L; Aquino, S F

2014-01-01

The present work aimed to investigate the microbial dynamics during the anaerobic treatment of the azo dye blue HRFL in bench scale upflow anaerobic sludge bed (UASB) reactor operated at ambient temperature. Sludge samples were collected under distinct operational phases, when the reactor were stable (low variation of color removal), to assess the effect of glucose and yeast extract as source of carbon and redox mediators, respectively. Reactors performance was evaluated based on COD (chemical oxygen demand) and color removal. The microbial dynamics were investigated by PCR-DGGE (Polimerase Chain Reaction - Denaturing Gradient of Gel Electrophoresis) technique by comparing the 16S rDNA profiles among samples. The results suggest that the composition of microorganisms changed from the beginning to the end of the reactor operation, probably in response to the presence of azo dye and/or its degradation byproducts. Despite the highest efficiency of color removal was observed in the presence of 500 mg/L of yeast extract (up to 93%), there were no differences regarding the microbial profiles that could indicate a microbial selection by the yeast extract addition. On the other hand Methosarcina barkeri was detected only in the end of operation when the best efficiencies on color removal occurred. Nevertheless the biomass selection observed in the last stages of UASB operation is probably a result of the washout of the sludge in response of accumulation of aromatic amines which led to tolerant and very active biomass that contributed to high efficiencies on color removal.

Biodegradation of azo dyes in cocultures of anaerobic granular sludge with aerobic aromatic amine degrading enrichment cultures

NARCIS (Netherlands)

Tan, N.C.G.; Prenefeta-Boldú, F.X.; Opsteeg, J.L.; Lettinga, G.; Field, J.A.

1999-01-01

A prerequisite for the mineralization (complete biodegradation) of many azo dyes is a combination of reductive and oxidative steps. In this study, the biodegradation of two azo dyes, 4-phenylazophenol (4-PAP) and Mordant Yellow 10 (4-sulfophenylazo-salicylic acid; MY10), was evaluated in batch

trans-Caryophyllene, a Natural Sesquiterpene, Causes Tracheal Smooth Muscle Relaxation through Blockade of Voltage-Dependent Ca2+ Channels

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Jader Santos Cruz

2012-10-01

Full Text Available trans-Caryophyllene is a major component in the essential oils of various species of medicinal plants used in popular medicine in Brazil. It belongs to the chemical class of the sesquiterpenes and has been the subject of a number of studies. Here, we evaluated the effects of this compound in airway smooth muscle. The biological activities of trans-caryophyllene were examined in isolated bath organs to investigate the effect in basal tonus. Electromechanical and pharmacomechanical couplings were evaluated through the responses to K+ depolarization and exposure to acetylcholine (ACh, respectively. Isolated cells of rat tracheal smooth muscle were used to investigate trans-caryophyllene effects on voltage-dependent Ca2+ channels by using the whole-cell voltage-clamp configuration of the patch-clamp technique. trans-Caryophyllene showed more efficiency in the blockade of electromechanical excitation-contraction coupling while it has only minor inhibitory effect on pharmacomechanical coupling. Epithelium removal does not modify tracheal smooth muscle response elicited by trans-caryophyllene in the pharmacomechanical coupling. Under Ca2+-free conditions, pre-exposure to trans-caryophyllene did not reduce the contraction induced by ACh in isolated rat tracheal smooth muscle, regardless of the presence of intact epithelium. In the whole-cell configuration, trans-caryophyllene (3 mM, inhibited the inward Ba2+ current (IBa to approximately 50% of control levels. Altogether, our results demonstrate that trans-caryophyllene has anti-spasmodic activity on rat tracheal smooth muscle which could be explained, at least in part, by the voltage-dependent Ca2+ channels blockade.

Synthesis, biological activity and computational studies of novel azo-compounds

International Nuclear Information System (INIS)

Ashraf, J.; Murtaza, S.; Mughal, E.U.; Sadiq, A.

2017-01-01

In the present protocol, we report the synthesis and characterization of some novel azo-compounds starting from 4-methoxyaniline and 4-aminophenazone, which were diazotized at low temperature. 4-nitrophenol, 2-aminobenzoic acid, benzamide, 4-aminobenzoic acid, resorcinol, o-bromonitrobenzene and 2-nitroaniline were used as active aromatic coupling compounds for the second step. The synthesized compounds were investigated for their potential antibacterial activities by using disc diffusion method against Escherichia coli, Shigellasonnei, Streptococcus pyrogenes, Staphylococcus aureus and Neisseria gonorrhoeae strains. They were also subjected to antioxidant activities by using DPPH method. Results revealed that the compounds of 4-methoxyaniline and 4-aminophenazone showed good antibacterial activity against all strains, where as some azo-compounds have moderate to good antioxidant activities. Furthermore, these compounds were studied by computational analysis. (author)

Thermal stability and degradation behavior of novel wholly aromatic azo polyamide-hydrazides

International Nuclear Information System (INIS)

Al-Ghamdia, R.F.; Fahmib, M.M.; Mohamed, N.A.

2005-01-01

Thermal stability and degradation behavior of a series of novel wholly aromatic azo polyamide-hydrazides have been investigated in nitrogen and in air atmospheres using differential scanning ealorimetry, thermogravimetry, infrared spectroscopy and elemental analysis. The influences of controlled structural variations and molecular weight on the thermal stability and degradation behavior of this series of polymers have also been studied. The structural differences were achieved by varying the content of para- and meta substituted phenylene rings incorporated within this series. The polymers were prepared by a low temperature solution polycondensation reaction of p aminosalicylic acid hydrazide and an equimolar amount of 4,4-azo dibenzoyl chloride [4,4 ADBC] or 3,3-azo dibenzoyl chloride [3,3ADBC] or mixtures of various molar ratios of 4,4ADBC and 3,3ADBC in anhydrous N,N- dimethyl acetamide [DMAc] containing lithium chloride as a solvent at -10 degree C. The results clearly reveal that these polymers are characterized by high thermal stability. Their weight loss occurred in three distinctive steps. The first was small and assigned to the evaporation of absorbed moisture. The second was appreciable and was attributed to the cyclo dehydration reaction of the hydrazide groups into 1,3,4-oxadiazole rings by losing water, combined with elimination of azo groups by losing molecular nitrogen. This is not a true degradation but rather a thermo-chemical transformation reaction of the azo polyamide-hydrasdes into the corresponding polyamide-l,3,4-oxadiazoles. The third was relatively severe and sharp, particularly in air, and corresponded to the decomposition of the resulting polyamide-l, 3,4-oxadiazoles. In both degradation atmospheres, the improved resistance to high temperatures was always associated with increased content of para- phenylene moieties of the investigated polymer. Further, with exception of 160-200 degree C temperature range, where the lower molecular weight

Comparison study of transparent RF-sputtered ITO/AZO and ITO/ZnO bilayers for near UV-OLED applications

Science.gov (United States)

Rezaie, Mahdiyar Nouri; Manavizadeh, Negin; Abadi, Ehsan Mohammadi Nasr; Nadimi, Ebrahim; Boroumand, Farhad Akbari

2017-01-01

Hybrid inorganic/organic light-emitting diodes have attracted much attention in the field of luminescent electronics due to the desired incorporation of high optoelectronic features of inorganic materials with the processability and variety of organic polymers. To generate and emit a near ultraviolet (N-UV) ray, wide band gap semiconductors can be applied in the organic light-emitting diodes (OLEDs). In this paper, zinc oxide (ZnO) and aluminum-doped ZnO (AZO) thin films are deposited by radio frequency (RF) sputtering above the ITO electrode and poly [2-methoxy-5-(2-ethyl-hexyloxy)-1,4-phenylene-vinylene] (MEH-PPV) conjugated polymer is utilized as a complementary p-type semiconductor in OLED structure. The impact of ZnO and AZO thickness on the structural, electrical, optical and morphological properties of ITO/AZO and ITO/ZnO bilayers are scrutinized and compared. Results show that with the enlargement of both ZnO and AZO film thickness, the physical properties are gradually improved resulting in the better quality of transparent conducting thin film. The average electrical resistivity of 8.4 × 10-4 and 1.1 × 10-3 Ω-cm, average sheet resistance of 32.9 and 42.3 Ω/sq, average transmittance of 88.3 and 87.3% and average FOM of 1.0 × 104 and 7.4 × 103 (Ω-cm)-1 are obtained for ITO/AZO and ITO/ZnO bilayers, respectively. Moreover, comparing the results indicates that the strain and the stress within the ITO/AZO bilayer are decreased nearly 19% with respect to ITO/ZnO bilayer which yield higher quality of crystal. Consequently, the physical properties of ITO/AZO bilayer is found to be superior regarding ITO/ZnO bilayer. For fabricated UV-OLEDs, the turn-on voltages, the characteristic energy (Et) and the total concentration of traps (Nt) for the devices with the structures of ITO/ZnO/MEH-PPV/Al and ITO/AZO/MEH-PPV/Al are obtained 12 and 14 V, 0.108 and 0.191 eV, 9.33 × 1016 and 5.22 × 1016 cm-3, respectively. Furthermore, according to the electroluminescence

trans-Double Bond-Containing Liposomes as Potential Carriers for Drug Delivery

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Giorgia Giacometti

2017-11-01

Full Text Available The use of liposomes has been crucial for investigations in biomimetic chemical biology as a membrane model and in medicinal chemistry for drug delivery. Liposomes are made of phospholipids whose biophysical characteristics strongly depend on the type of fatty acid moiety, where natural unsaturated lipids always have the double bond geometry in the cis configuration. The influence of lipid double bond configuration had not been considered so far with respect to the competence of liposomes in delivery. We were interested in evaluating possible changes in the molecular properties induced by the conversion of the double bond from cis to trans geometry. Here we report on the effects of the addition of trans-phospholipids supplied in different amounts to other liposome constituents (cholesterol, neutral phospholipids and cationic surfactants, on the size, ζ-potential and stability of liposomal formulations and on their ability to encapsulate two dyes such as rhodamine B and fluorescein. From a biotechnological point of view, trans-containing liposomes proved to have different characteristics from those containing the cis analogues, and to influence the incorporation and release of the dyes. These results open new perspectives in the use of the unnatural lipid geometry, for the purpose of changing liposome behavior and/or of obtaining molecular interferences, also in view of synergic effects of cell toxicity, especially in antitumoral strategies.

Lightlike Hypersurfaces in Indefinite Trans-Sasakian Manifolds

International Nuclear Information System (INIS)

Massamba, Fortune

2010-07-01

This paper deals with lightlike hypersurfaces of indefinite trans-Sasakian manifolds of type (α, β), tangent to the structure vector field. Characterization Theorems on parallel vector fields, integrable distributions, minimal distributions, Ricci-semi symmetric, geodesibility of lightlike hypersurfaces are obtained. The geometric configuration of lightlike hypersurfaces is established. We prove, under some conditions, that there are no parallel and totally contact umbilical lightlike hypersurfaces of trans-Sasakian space forms, tangent to the structure vector field. We show that there exists a totally umbilical distribution in an Einstein parallel lightlike hypersurface which does not contain the structure vector field. We characterize the normal bundle along any totally contact umbilical leaf of an integrable screen distribution. We finally prove that the geometry of any leaf of an integrable distribution is closely related to the geometry of a normal bundle and its image under φ-bar. (author)

Low-temperature-fabricated ZnO, AZO, and SnO{sub 2} nanoparticle-based dye-sensitized solar cells

Energy Technology Data Exchange (ETDEWEB)

Kim, Hong Hee; Park, Cheolmin; Choi, Wonkook; Cho, Sungjae; Moon, Byungjoon; Son, Dongick [Korea Institute of Science and Technology, Seoul (Korea, Republic of); Yonsei University, Seoul (Korea, Republic of)

2014-11-15

The authors investigated the microstructural and the electrical properties of ZnO, AZO, and SnO{sub 2} based dye-sensitized solar cells (DSSCs) fabricated using a low-temperature-processed (200 .deg. C) dyesensitized ZnO, AZO, and SnO{sub 2} nanoparticle thin film and a Pt catalyst deposited on ITO/glass by RF magnetron sputtering. A hydropolymer containing PEG (poly ethylene glycol) and PEO (poly ethylene oxide) is used to make uniformly-distributed ZnO, AZO, and SnO{sub 2} nanoparticle layer which forms a nano porous ZnO, AZO, and SnO{sub 2} network after heat treatment. The layer is then dye sensitized and sandwiched between two electrodes in an electrolyte to make a DSSC device. The highest measured parameters, the short-circuit current density (J{sub sc}), the open circuit potential (V{sub oc}), the fill factor (FF), and power conversion efficiency (η), of the DSSC fabricated wander optimized conditions were observed to be 5.10 mA/cm{sup 2}, 0.61 V, 0.46, and 1.43%, respectively.

Azo dye reduction by mesophilic and thermophilic anaerobic consortia

NARCIS (Netherlands)

Santos, dos A.B.; Madrid, de M.P.; Stams, A.J.M.; Lier, van J.B.; Cervantes, F.J.

2005-01-01

The reduction of the azo dye model compounds Reactive Red 2 (RR2) and Reactive Orange 14 (RO14) by mesophilic (30 C) and thermophilic (55 C) anaerobic consortia was studied in batch assays. The contribution of fermentative and methanogenic microorganisms in both temperatures was evaluated in the

UV durable colour pigment doped SmA liquid crystal composites for outdoor trans-reflective bi-stable displays

Science.gov (United States)

Xu, H.; Davey, A. B.; Crossland, W. A.; Chu, D. P.

2012-10-01

High brightness trans-reflective bi-stable displays based on smectic A (SmA) liquid crystals (LCs) can have nearly perfect transparency in the clear state and very high reflection in the scattered state. Because the LC material in use is stable under UV radiation, this kind of displays can stand for strong day-light and therefore be ideal for outdoor applications from e-books to public signage and advertisement. However, the colour application has been limited because the traditional colourants in use are conventional dyes which are lack of UV stability and that their colours are easily photo bleached. Here we present a colour SmA display demonstrator using pigments as colourant. Mixing pigments with SmA LCs and maintain the desirable optical switching performance is not straightforward. We show here how it can be done, including how to obtain fine sized pigment nano-particles, the effects of particle size and size distribution on the display performance. Our optimized pigments/SmA compositions can be driven by a low frequency waveform (~101Hz) to a scattered state to exhibit colour while by a high frequency waveform (~103Hz) to a cleared state showing no colour. Finally, we will present its excellent UV life-time (at least <7.2 years) in comparison with that of dye composition (~2.4 years). The complex interaction of pigment nano-particles with LC molecules and the resulting effects on the LC electro-optical performances are still to be fully understood. We hope this work will not only demonstrate a new and practical approach for outdoor reflective colour displays but also provide a new material system for fundamental liquid crystal colloid research work.

Structural, optical and nonlinear optical studies of AZO thin film prepared by SILAR method for electro-optic applications

Science.gov (United States)

Edison, D. Joseph; Nirmala, W.; Kumar, K. Deva Arun; Valanarasu, S.; Ganesh, V.; Shkir, Mohd.; AlFaify, S.

2017-10-01

Aluminium doped (i.e. 3 at%) zinc oxide (AZO) thin films were prepared by simple successive ionic layer adsorption and reaction (SILAR) method with different dipping cycles. The structural and surface morphology of AZO thin films were studied by using X-ray diffraction (XRD) and scanning electron microscopy (SEM). The optical parameters such as, transmittance, band gap, refractive index, extinction coefficient, dielectric constant and nonlinear optical properties of AZO films were investigated. XRD pattern revealed the formation of hexagonal phase ZnO and the intensity of the film was found to increase with increasing dipping cycle. The crystallite size was found to be in the range of 29-37 nm. Scanning Electron Microscope (SEM) images show the presence of small sized grains, revealing that the smoothest surface was obtained at all the films. The EDAX spectrum of AZO conforms the presence of Zn, O and Al. The optical transmittance in the visible region is high 87% and the band gap value is 3.23 eV. The optical transmittance is decreased with respect to dipping cycles. The room temperature PL studies revealed that the AZO films prepared at (30 cycles) has good film quality with lesser defect density. The third order nonlinear optical parameters were also studied using Z-scan technique to know the applications of deposited films in nonlinear devices. The third order nonlinear susceptibility value is found to be 1.69 × 10-7, 3.34 × 10-8, 1.33 × 10-7and 2.52 × 10-7 for AZO films deposited after 15, 20, 25 and 30 dipping cycles.

Voltammetric determination of zirconium using azo compounds

International Nuclear Information System (INIS)

Orshulyak, O.O.; Levitskaya, G.D.

2008-01-01

The optimum conditions for zirconium complexation with azo compounds are found. The applicability of Eriochrome Red B, Calcon, and Calcion to the voltammetric determination of zirconium, total Zr(IV) and Hf(IV), and Zr(IV) in the presence of Zn(II), Cu(II), Cd(II), Ni(II), or Ti(IV) is demonstrated. The developed procedures are used to determine zirconium in a terbium alloy and in an alloy for airplane wheel drums [ru

Kinetics of molybdenum(6) complexation with o,o'-dihydroxyazo compounds or heterocyclic azo compounds in the presence of hydroxylamine

International Nuclear Information System (INIS)

Kochelaeva, G.A.; Degtyarev, M.Yu.; Ivanov, V.M.; Prokhorova, G.V.; Figurovskaya, V.N.

1999-01-01

The kinetics of complexation in the system molybdenum(6)-azo compound-hydroxylamine was studied. Azo compounds of the types o,o'-dihydroxyazo compounds, such as Lyumogallion IREA and Magneson IREA, and heterocyclic azo compounds, such as 4-(2-pyridylazo)resorcinol and 2-(5-bromo-2-pyridylazo)-5-diethylaminophenol, were studied. The formation of mixed-ligand complexes with the ratio of component 1 : 1 : 1 was detected. Rate constants, activation energies, and stability constants of the forming compounds were evaluated. It was concluded that the reagents under study are promising for the analytical chemistry of molybdenum [ru

Influence of mass transfer and chemical reaction on ozonation of azo dyes

Energy Technology Data Exchange (ETDEWEB)

Choi, I.S.; Wiesmann, U. [Dept. of Environmental Engineering, Technical Univ. of Berlin, Berlin (Germany)

2003-07-01

Azo dyes can be only mineralised by chemical oxidation. In this paper the oxidation of reactive black 5 (RB 5) and reactive orange 96 (RO 96) with concentrations between 35 and 5700 mgL{sup -1} (RB 5) and between 20 and 2050 mgL{sup -1} (RO 96) is investigated. A lab scale bubble column was used, which was gassed by a mixture of O{sub 2} and O{sub 3}. The oxidation rate was influenced by mass transfer for all dye concentrations used. For lower dye concentrations mass transfer alone was decisive for reaction rate showing an enhancement factor of E {approx} 1. However, in the region of higher dye concentrations, the slope of the decreasing ozone concentration inside the liquid boundary layer increases more and more with increasing dye concentration as a result of a chemical oxidation. Therefore, the enhancement factor depends on the kind and concentration of the azo dyes. For RB 5 as an diazo dye an enhancement factor of E = 9 was observed for 3800 mgL{sup -1}, RO 96 as a mono azo dye with a remarkable higher chemical oxidation rate shows an E = 17 already for 2050 mgL{sup -1}. (orig.)

Electrochemical characterization of azo dye (E)-1-(4-((4-(phenylamino)phenyl)diazenyl)phenyl)ethanone (DPA)

International Nuclear Information System (INIS)

Surucu, Ozge; Abaci, Serdar; Seferoğlu, Zeynel

2016-01-01

Highlights: • Electrochemical characterization of azo dye DPA was performed. • Pencil graphite electrode was used as working electrode. • Cyclic voltammetry was used to determine the effect of scan rate and pH. • Chronoamperometry was used to determine diffusion constant. • Square wave voltammetry verified the results of cyclic voltammetry. - Abstract: An enormous range of possible dyes are available, especially as the starting molecules are readily available and cheap. As other dye classes become less viable from either an environmental or economic reasons, azo dyes come to the forefront. Therefore, electrochemical characterization of a novel synthesized azo dye (E)-1-(4-((4-(phenylamino) phenyl)diazenyl)phenyl)ethanone was achieved for the first time. Cyclic voltammetry, chronoamperometry and square wave voltammetry techniques were used to investigate the electrochemical behavior and electrocatalytic effect of azo dye (E)-1-(4-((4-(phenylamino) phenyl)diazenyl)phenyl)ethanone at pencil graphite electrode. Cyclic voltammograms were utilized to determine the effect of scan rate and pH on the peak current and peak potential. Chronoamperometry technique was used to determine diffusion constant, D and the type of adsorption isotherms. The kinetics parameters which were the apparent electron transfer rate constant, k s and charge transfer coefficient, α were calculated. Square wave voltammetry was used to verify responses of cyclic voltammetry technique.

Growth of KOH etched AZO nanorods and investigation of its back scattering effect in thin film a-Si solar cell

Science.gov (United States)

Sharma, Jayasree Roy; Mitra, Suchismita; Ghosh, Hemanta; Das, Gourab; Bose, Sukanta; Mandal, Sourav; Mukhopadhyay, Sumita; Saha, Hiranmay; Barua, A. K.

2018-02-01

In order to increase the stabilized efficiencies of thin film silicon (TFS) solar cells it is necessary to use better light management techniques. Texturization by etching of sputtered aluminum doped zinc oxide (Al:ZnO or AZO) films has opened up a variety of promises to optimize light trapping schemes. RF sputtered AZO film has been etched by potassium hydroxide (KOH). A systematic study of etching conditions such as etchant concentration, etching time, temperature management etc. have been performed in search of improved electrical and optical performances of the films. The change in etching conditions has exhibited a noticeable effect on the structure of AZO films for which the light trapping effect differs. After optimizing the etching conditions, nanorods have been found on the substrate. Hence, nanorods have been developed only by chemical etching, rather than the conventional development method (hydrothermal method, sol-gel method, electrolysis method etc.). The optimized etched substrate has 82% transmittance, moderate haze in the visible range and sheet resistance ∼13 (Ω/□). The developed nanorods (optimized etched substrate) provide better light trapping within the cell as the optical path length has been increased by using the nanorods. This provides an effect on carrier collection as well as the efficiency in a-Si solar cells. Finite difference time domain (FDTD) simulations have been performed to observe the light trapping by AZO nanorods formed on sputtered AZO films. For a p-i-n solar cell developed on AZO nanorods coated with sputtered AZO films, it has been found through simulations that, the incident light is back scattered into the absorbing layer, leading to an increase in photogenerated current and hence higher efficiency. It has been found that, the light that passes through the nanorods is not getting absorbed and maximum amount of light is back scattered towards the solar cell.

Research on Synthesis of New Azo Calix[4]arene and its Dyeing Properties

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Tang Jun

2015-01-01

Full Text Available With the raw materials of calix[4]arene, benzocaine, tricaine and procaine hydrochloride, three new azo calix[4]arene derivatives—6a, 6b and 6c are synthesized by diazotization–coupling reaction of an aromatic amine, with its yield of 83%, 81% and 83% respectively. The structural characterization is in a way of IR, 1H NMR and elemental analysis. This paper investigates the spectral properties of azo calix[4]arene derivatives under different solution pH conditions through the UV–visible spectroscopy, and researches the dyeing properties through the dyeing curve, color yield test and fastness test. The results show that, with the increase of pH value, the azo calix[4]arene derivatives—6a, 6b and 6c form azo–hydrazone tautomeric isomers with the maximum absorption peak redshift; the dyeing effect of the compound is good, of which the dye–uptake rate of the compound 6a is as high as 78%; the surface depth of color yield is 2.798, and the dry and wet rubbing fastness and the soaping fastness are respectively 4, which is a better disperse dye.

Isolation and screening of azo dye decolorizing bacterial isolates from dye-contaminated textile wastewater

Directory of Open Access Journals (Sweden)

Shahid Mahmood

2011-04-01

Full Text Available Azo dyes are released into wastewater streams without any pretreatment and pollute water and soilenvironments. To prevent contamination of our vulnerable resources, removal of these dye pollutants is of greatimportance. For this purpose, wastewater samples were collected from dye-contaminated sites of Faisalabad. About200 bacterial isolates were isolated through enrichment and then tested for their potential to remove RemazolBlack-B azo dye in liquid medium. Five bacterial isolates capable of degrading Remazol Black-B azo dye efficientlywere screened through experimentation on modified mineral salt medium. Isolate SS1 (collected from wastewater ofSupreme Textile Industry was able to completely remove the Remazol Black-B dye from the liquid medium in 18 h.Further, the isolate showed the best performance at the dye concentration of 100 mg L-1 medium (pH 7 and attemperature 35oC. Similarly, yeast extract proved to be the best carbon source for decolorization purpose. Theresults imply that the isolate SS1 could be used for the removal of the reactive dyes from textile effluents.

Equilibrium contact angle or the most-stable contact angle?

Science.gov (United States)

Montes Ruiz-Cabello, F J; Rodríguez-Valverde, M A; Cabrerizo-Vílchez, M A

2014-04-01

It is well-established that the equilibrium contact angle in a thermodynamic framework is an "unattainable" contact angle. Instead, the most-stable contact angle obtained from mechanical stimuli of the system is indeed experimentally accessible. Monitoring the susceptibility of a sessile drop to a mechanical stimulus enables to identify the most stable drop configuration within the practical range of contact angle hysteresis. Two different stimuli may be used with sessile drops: mechanical vibration and tilting. The most stable drop against vibration should reveal the changeless contact angle but against the gravity force, it should reveal the highest resistance to slide down. After the corresponding mechanical stimulus, once the excited drop configuration is examined, the focus will be on the contact angle of the initial drop configuration. This methodology needs to map significantly the static drop configurations with different stable contact angles. The most-stable contact angle, together with the advancing and receding contact angles, completes the description of physically realizable configurations of a solid-liquid system. Since the most-stable contact angle is energetically significant, it may be used in the Wenzel, Cassie or Cassie-Baxter equations accordingly or for the surface energy evaluation. © 2013 Elsevier B.V. All rights reserved.

All-fiber maskless lithographic technology to form microcircular interference pattern on Azo polymer film

Science.gov (United States)

Kim, Junki; Jung, Yongmin; Oh, Kyunghwan; Chun, Chaemin; Hong, Jeachul; Kim, Dongyu

2005-03-01

We report a novel all-fiber, maskless lithograpic technology to form various concentric grating patterns for micro zone plate on azo polymer film. The proposed technology is based on the interference pattern out of the cleaved end of a coreless silica fiber (CSF)-single mode fiber (SMF) composite. The light guided along SMF expands into the CSF segment to generate various circular interference patterns depending on the length of CSF. Interference patterns are experimentally observed when the CSF length is over a certain length and the finer spacing between the concentric rings are obtained for a longer CSF. By using beam propagation method (BPM) package, we could further investigated the concentric interference patterns in terms of intensity distribution and fringe spacing as a function of CSF length. These intereference patterns are directly projected over azo polymer film and their intensity distrubution formed surface relief grating (SRG) patterns. Compared to photoresist films azo polymer layers produce surface relief grating (SRG), where the actual mass of layer is modulated rather than refractive index. The geometric parameters of the CSF length as well as diameter and the spacing between the cleaved end of a CSF and azo polymer film, were found to play a major role to generate various concentric structures. With the demonstration of the circular SRG patterns, we confirmed that the proposed technique do have an ample potential to fabricate micro fresnel zone plate, that could find applications in lens arrays for optical beam formings as well as compact photonic devices.

Influence of chemical structures on biodegradation of azo dyes by ...

African Journals Online (AJOL)

Influence of chemical structures on biodegradation of azo dyes by Pseudomonas sp. NA Oranusi, CJ Ogugbue. Abstract. No Abstract. Global Journal of Environmental Sciences Vol. 5(1) 2006: 19-25. Full Text: EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT.

Influence of Ag doping on structural, optical, and photoluminescence properties of nanostructured AZO films by sol–gel technique

International Nuclear Information System (INIS)

Khan, Firoz; Baek, Seong-Ho; Kim, Jae Hyun

2014-01-01

Graphical abstract: The optical band gap of the Ag–AZO film first decreased to a value of ∼3.31 eV for a 1% Ag/Zn atomic ratio from a value of ∼3.69 for undoped AZO film. For higher values (beyond a 1% Ag/Zn atomic ratio) of Ag doping, the values of Eg started to increase and finally attained a value of ∼3.66 eV for an Ag/Zn 3% atomic ratio. The photoluminescence (PL) studies showed that the relative PL intensity of the Ag–AZO films in blue (IB) and green (IG) regions increased with Ag doping. The PL positions of these peaks were blue shifted with increased Ag content up to an Ag/Zn atomic ratio of 3%. The increase in IB and IG is due to the charge difference between Ag + and Zn 2+ , whereas shifting of the PL positions is due to the size of Ag + and Zn 2+ ions. -- Highlights: • The optical band gap of the Ag–AZO film is tuned with Ag doping. • The PL intensity of the Ag–AZO film in visible region is increased with Ag doping. • The PL positions of these peaks were blue shifted with increased Ag content. • The increase in I B and I G is due to the charge difference between Ag + and Zn 2+ . • The shifting of the PL positions is due to the size of Ag + and Zn 2+ ions. -- Abstract: The effects of Ag doping on the structural, electrical, optical, and photoluminescence properties of sol-gel derived Al rich zinc oxide (Ag–AZO) films are studied. The Al/Zn atomic ratio was constant (∼20%) in all the films, whereas the Ag/Zn atomic ratio varied from 0% to 3%. All the films were highly transparent in the 400–1200 nm wavelength range. The XRD results and surface morphologies of the films confirmed that the grain size increased with Ag doping. The optical band gap (E g ) of the Ag–AZO film first decreased to a value of ∼3.31 eV for a 1% Ag/Zn atomic ratio from a value of ∼3.69 for undoped AZO film. For higher values (beyond a 1% Ag/Zn atomic ratio) of Ag doping, the values of E g started to increase and finally attained a value of ∼3.66 e

Synthesis, characterization and dyeing assessment of novel acid azo dyes and mordent acid azo dyes based on 2-hydroxy-4-methoxybenzophenone on wool and silk fabrics

Directory of Open Access Journals (Sweden)

DHIRUBHAI J. DESAI

2010-05-01

Full Text Available Novel acid mono azo and mordent acid mono azo dyes were synthesised by the coupling of diazonium salt solution of different aromatic amines with 2-hydroxy-4-methoxybenzophenone. The resulting dyes were characterized by spectral techniques, i.e., elemental analysis, IR, 1H-NMR and UV–visible spectroscopy. The dyeing performance of all the dyes was evaluated on wool and silk fabrics. The dyeing of chrome pre-treated wool and silk fabrics showed better hues on mordented fabrics. Dyeing of wool and silk fabrics resulted in pinkish blue to red shades with very good depth and levelness. The dyed fabrics showed excellent to very good light, washing, perspiration, sublimation and rubbing fastness. The results of antibacterial studies of chrome pre-treated fabrics revealed that the toxicity of mordented dyes against Escherichia coli, Staphylococcus aureus, Salmonella typhi, Bacillus subtilis bacteria was fairly good.

Potential energy profile, structural, vibrational and reactivity descriptors of trans-2-methoxycinnamic acid by FTIR, FT-Raman and quantum chemical studies

Science.gov (United States)

Arjunan, V.; Anitha, R.; Thenmozhi, S.; Marchewka, M. K.; Mohan, S.

2016-06-01

The stable conformers of trans-2-methoxycinnamic acid (trans-2MCA) are determined by potential energy profile analysis. The energies of the s-cis and s-trans conformers of trans-2MCA determined by B3LYP/cc-pVTZ method are -612.9788331 Hartrees and -612.9780953 Hartrees, respectively. The vibrational and electronic investigations of the stable s-cis and s-trans conformers of trans-2-methoxycinnamic acid have been carried out extensively with FTIR and FT-Raman spectral techniques. The s-cis conformer (I) with a (C16-C17-C18-O19) dihedral angle equal to 0° is found to be more favoured relative to the one s-trans (II) with (C16-C17-C18-O19) = 180°, possibly due to delocalization, hydrogen bonding and steric repulsion effects between the methoxy and acrylic acid groups. The DFT studies are performed with B3LYP method by utilizing 6-311++G** and cc-pVTZ basis sets to determine the structure, thermodynamic properties, vibrational characteristics and chemical shifts of the compound. The total dipole moments of the conformers determined by B3LYP/cc-pVTZ method are 3.35 D and 4.87 D for s-cis and s-trans, respectively. It reveals the higher polarity of s-trans conformer of trans-2MCA molecule. The electronic and steric influence of the methoxy group on the skeletal frequencies has been analysed. The energies of the frontier molecular orbitals and the LUMO-HOMO energy gap have been determined. The MEP of s-cis conformer lie in the range +1.374e × 10-2 to -1.374e × 10-2 while for s-trans it is +1.591e × 10-2 to -1.591e × 10-2. The total electron density of s-cis conformer lie in the range +5.273e × 10-2 to -5.273e × 10-2 while for s-trans it is +5.403e × 10-2 to -5.403e × 10-2. The MEP and total electron density shows that the s-cis conformer is less polar, less reactive and more stable than the s-trans conformer. All the reactivity descriptors of the molecule have been discussed. Intramolecular electronic interactions and their stabilisation energies have analysed

Interfacial electronic structure of C{sub 60}/ZnPc/AZO on photoemission spectroscopy for organic photovoltaic applications

Energy Technology Data Exchange (ETDEWEB)

Heo, Nari; Kim, Yoonsu; Jung, Yunwoo; Cheon, Suyoung; Cho, Soohaeng [Department of Physics, Yonsei University, Wonju 220-710 (Korea, Republic of); Cho, Sang Wan, E-mail: dio8027@yonsei.ac.kr [Department of Physics, Yonsei University, Wonju 220-710 (Korea, Republic of); Park, Soohyung; Yi, Yeonjin [Institute of Physics and Applied Physics, Yonsei University, Seoul 120-749 (Korea, Republic of); Smith, Kevin E. [Department of Physics, Boston University, 590 Commonwealth Ave, Boston, MA 02215 (United States)

2016-10-20

Highlights: • The electronic structure of a bilayer on AZO has been evaluated by UPS and XPS. • The energy difference between the ZnPc HOMO and the C{sub 60} LUMO was determined. • The result is discussed in terms of the work function and resistivity of each TCO. - Abstract: The interfacial electronic structure of a bilayer of fullerene (C{sub 60}) and zinc phthalocyanine (ZnPc) grown on aluminum-doped zinc oxide (AZO) substrates has been evaluated by X-ray and ultraviolet photoemission spectroscopy. The energy difference between the highest occupied molecular orbital (HOMO) level of the ZnPc layer and the lowest unoccupied molecular orbital (LUMO) level of the C{sub 60} layer (E{sup D}{sub HOMO} − E{sup A}{sub LUMO}) was determined and compared to that grown on an indium tin oxide (ITO) substrate. The E{sup D}{sub HOMO} − E{sup A}{sub LUMO} value of the heterojunction on AZO was 1.4 eV, while that on ITO was 1.1 eV. This result is discussed in terms of the differences of the work function and resistivity of each transparent conductive oxide. We also obtained complete energy level diagrams of C{sub 60}/ZnPc/AZO and C{sub 60}/ZnPc/ITO.

Influence of a Crosslinker Containing an Azo Group on the Actuation Properties of a Photoactuating LCE System

Directory of Open Access Journals (Sweden)

Lukas B. Braun

2016-12-01

Full Text Available Photoactuating liquid crystalline elastomers (LCE are promising candidates for an application as artificial muscles in microdevices. In this work, we demonstrate that by optimizing (1 the illumination conditions and (2 the mixture of azo monomer and azo crosslinker, thick films of an all-azo LCE can be prepared, which show a strong length change without bending during photoactuation. This becomes possible by working with white light (about 440 nm, whose absorption is low, leading to a large penetration depth. By adding an azo crosslinker to a previously prepared system, several improvements of the actuation properties—like a stronger photoactuation at lower operational temperatures—could be achieved. In addition, films of different crosslinker concentrations and thicknesses were produced by photopolymerization at varying temperatures within a magnetic field, and their thermo- and photoresponsive behavior was investigated. An extraordinarily strong maximal thermal actuation of 46% and—by exposure to white light at 70 °C—a photoresponsive change in length of up to 40% in just about 13 s could be obtained. Even densely crosslinked samples were still able to photoactuate remarkably. Isothermal back-deformation could either be achieved by irradiation with red light (7 min or by keeping the film in the dark (13 min.

ZnO nanorods/AZO photoanode for perovskite solar cells fabricated in ambient air

Science.gov (United States)

La Ferrara, Vera; De Maria, Antonella; Rametta, Gabriella; Della Noce, Marco; Vittoria Mercaldo, Lucia; Borriello, Carmela; Bruno, Annalisa; Delli Veneri, Paola

2017-08-01

ZnO nanorods are a good candidate for replacing standard photoanodes, such as TiO2, in perovskite solar cells and in principle superseding the high performances already obtained. This is possible because ZnO nanorods have a fast electron transport rate due to their large surface area. An array of ZnO nanorods is grown by chemical bath deposition starting from Al-doped ZnO (AZO) used both as a seed layer and as an efficient transparent anode in the visible spectral range. In particular, in this work we fabricate methylammonium lead iodide (CH3NH3PbI3) perovskite solar cells using glass/AZO/ZnO nanorods/perovskite/Spiro-OMeTAD/Au as the architecture. The growth of ZnO nanorods has been optimized by varying the precursor concentrations, growth time and solution temperature. All the fabrication process and photovoltaic characterizations have been carried out in ambient air and the devices have not been encapsulated. Power conversion efficiency as high as 7.0% has been obtained with a good stability over 20 d. This is the highest reported value to the best of our knowledge and it is a promising result for the development of perovskite solar cells based on ZnO nanorods and AZO.

Aerobic decolourization of two reactive azo dyes under varying ...

African Journals Online (AJOL)

Bacillus cereus isolated from dye industrial waste, that is, effluent and soil samples was screened for its ability to decolourize two reactive azo dye – cibacron black PSG and cibacron red P4B under aerobic conditions at pH 7 and incubated at 35°C over a five day period. Different carbon and nitrogen sources were used for ...

Reductive decolourisation of azo dyes by mesophilic and thermophilic methanogenic consortia

NARCIS (Netherlands)

Cervantes, F.J.; Santos, dos A.B.; Madrid, de M.P.; Stams, A.J.M.; Lier, van J.B.

2005-01-01

The contribution of acidogenic bacteria and methanogenic archaea on the reductive decolourisation of azo dyes was assessed in anaerobic granular sludge. Acidogenic bacteria appeared to play an important role in the decolourising processes when glucose was provided as an electron donor; whereas

Efeitos dos parâmetros operacionais na fotodegradação do azo corante direct red 23 na interface dióxido de titânio/água Effects of operational parameters on the photodegradation of direct red 23 azo dye at the titanium dioxide/water interface

Directory of Open Access Journals (Sweden)

Débora Nobile Clausen

2007-01-01

Full Text Available The decolorization and degradation of direct red 23 azo dye have been investigated in aqueous suspension of titanium dioxide under artificial irradiation. The effects of some operational parameters such as azo dye concentration, catalyst loading, and solution pH were investigated at 30.0 ºC and optimized values were obtained. The first-order kinetic model was used to discuss the results. The UV-Vis spectra changes showed that the azo dye sample, collected after 6 h irradiation, was 98% decolorized while the residual total carbon was 97.9% degraded, indicating simultaneous photodecolorization and degradation.

Optothermal Switching of Cholesteric Liquid Crystals: A Study of Azobenzene Derivatives and Laser Wavelengths

Directory of Open Access Journals (Sweden)

Tai-Chieh Huang

2015-09-01

Full Text Available The laser-initiated thermal (optothermal switching of cholesteric liquid crystals (CLCs is characterized by using different azobenzene (Azo derivatives and laser wavelengths. Under 405-nm laser irradiation, Azo-doped CLCs undergo phase transition from cholesteric to isotropic. No cis-to-trans photoisomerization occurs when the 405-nm laser irradiation is blocked because only a single laser is used. The fast response of Azo-doped CLCs under the on–off switching of the 405-nm laser occurs because of the optothermal effect of the system. The 660-nm laser, which cannot be used as irradiation to generate the trans–cis photoisomerization of Azo, is used in Anthraquinone (AQ-Azo-doped CLCs to examine the optothermal effect of doped Azo. The results show that the LC-like Azo derivative bearing two methyl groups ortho to the Azo moiety (A4 can greatly lower the clearing temperature and generate large amount of heat in AQ-A4-doped CLCs.

Synthesis and characterization of 5-amino-2-((3-hydroxy-4-((3-hydroxyphenyl phenyl diazenyl phenol and its Cu(II complex – a strategy toward developing azo complexes for reduction of cytotoxicity

Directory of Open Access Journals (Sweden)

Durba Ganguly

2014-12-01

Full Text Available A major drawback of azo compounds is their associated toxicity, often carcinogenic, which is related to the reduction of the azo bond. This study intends to re-investigate this behavior by studying 5-amino-2-((3-hydroxy-4-((3-hydroxyphenyl phenyl diazenyl phenol (AHPD, a compound containing two azo bonds. Interaction of AHPD and its dimeric Cu(II complex with bacterial strains Escherichia coli and Staphylococcus aureus revealed the complex was less toxic. Reductive cleavage of the azo bond in AHPD and the complex followed using cytochrome c reductase (a model azo-reductase as well as azo-reductase enzymes obtained from bacterial cell extracts. Degradation of the azo bond was less in the complex allowing us to correlate the observed cytotoxicity. Cyclic voltammetry on AHPD and the complex support observations of enzyme assay experiments. These were particularly useful in realizing the formation of amines as an outcome of the reductive cleavage of azo bonds in AHPD that could not be identified through an enzyme assay. Results suggest that complex formation of azo compounds could be a means to control the formation of amines responsible for cytotoxicity. Studies carried out on bacterial cells for mere simplicity bear significance for multicellular organisms and could be important for human beings involved with the preparation and utilization of azo dyes.

Aerobic Biodegradation Characteristic of Different Water-Soluble Azo Dyes

Directory of Open Access Journals (Sweden)

Shixiong Sheng

2017-12-01

Full Text Available This study investigated the biodegradation performance and characteristics of Sudan I and Acid Orange 7 (AO7 to improve the biological dye removal efficiency in wastewater and optimize the treatment process. The dyes with different water-solubility and similar molecular structure were biologically treated under aerobic condition in parallel continuous-flow mixed stirred reactors. The biophase analysis using microscopic examination suggested that the removal process of the two azo dyes is different. Removal of Sudan I was through biosorption, since it easily assembled and adsorbed on the surface of zoogloea due to its insolubility, while AO7 was biodegraded incompletely and bioconverted, the AO7 molecule was decomposed to benzene series and inorganic ions, since it could reach the interior area of zoogloea due to the low oxidation-reduction potential conditions and corresponding anaerobic microorganisms. The transformation of NH3-N, SO42− together with the presence of tryptophan-like components confirm that AO7 can be decomposed to non-toxic products in an aerobic bioreactor. This study provides a theoretical basis for the use of biosorption or biodegradation mechanisms for the treatment of different azo dyes in wastewater.

Self-assembled graphene/azo polyelectrolyte multilayer film and its application in electrochemical energy storage device.

Science.gov (United States)

Wang, Dongrui; Wang, Xiaogong

2011-03-01

Graphene/azo polyelectrolyte multilayer films were fabricated through electrostatic layer-by-layer (LbL) self-assembly, and their performance as electrochemical capacitor electrode was investigated. Cationic azo polyelectrolyte (QP4VP-co-PCN) was synthesized through radical polymerization, postpolymerization azo coupling reaction, and quaternization. Negatively charged graphene nanosheets were prepared by a chemically modified method. The LbL films were obtained by alternately dipping a piece of the pretreated substrates in the QP4VP-co-PCN and nanosheet solutions. The processes were repeated until the films with required numbers of bilayers were obtained. The self-assembly and multilayer surface morphology were characterized by UV-vis spectroscopy, AFM, SEM, and TEM. The performance of the LbL films as electrochemical capacitor electrode was estimated using cyclic voltammetry. Results show that the graphene nanosheets are densely packed in the multilayers and form random graphene network. The azo polyelectrolyte cohesively interacts with the nanosheets in the multilayer structure, which prevents agglomeration of graphene nanosheets. The sheet resistance of the LbL films decreases with the increase of the layer numbers and reaches the stationary value of 1.0 × 10(6) Ω/square for the film with 15 bilayers. At a scanning rate of 50 mV/s, the LbL film with 9 bilayers shows a gravimetric specific capacitance of 49 F/g in 1.0 M Na(2)SO(4) solution. The LbL films developed in this work could be a promising type of the electrode materials for electric energy storage devices.

An autonomic self-healing organogel with a photo-mediated modulus

KAUST Repository

Xiong, Yubing

2016-11-15

A new method is described for fabricating autonomic, self-healing, deformable organogels. We combined imidazolium-based poly(ionic liquid) (PIL) and azobenzene-grafted poly(carboxylic acid) (PAA-Azo) in N,N-dimethyl formamide. Further, complexing PIL with unirradiated (trans) or irradiated (cis) PAA-Azo tuned the elastic modulus of the organogel. © 2016 The Royal Society of Chemistry.

An autonomic self-healing organogel with a photo-mediated modulus

KAUST Repository

Xiong, Yubing; Chen, Zhijun; Wang, Hong; Ackermann, Lisa Maria; Klapper, Markus; Butt, Hans Jü rgen; Wu, Si

2016-01-01

A new method is described for fabricating autonomic, self-healing, deformable organogels. We combined imidazolium-based poly(ionic liquid) (PIL) and azobenzene-grafted poly(carboxylic acid) (PAA-Azo) in N,N-dimethyl formamide. Further, complexing PIL with unirradiated (trans) or irradiated (cis) PAA-Azo tuned the elastic modulus of the organogel. © 2016 The Royal Society of Chemistry.

AZO Thin Films by Sol-Gel Process for Integrated Optics

Directory of Open Access Journals (Sweden)

Azzedine Boudrioua

2013-07-01

Full Text Available Undoped and aluminum-doped zinc oxide (AZO thin films are prepared by the sol-gel process. Zinc acetate dihydrate, ethanol, and monoethanolamine are used as precursor, solvent, and stabilizer, respectively. In the case of AZO, aluminum nitrate nonahydrate is added to the precursor solution with an atomic percentage equal to 1 and 2 at.% Al. The multi thin layers are deposited by spin-coating onto glass substrates, and are transformed into ZnO upon annealing at 550 °C. Films display a strong preferential orientation, with high values for the Texture Coefficients (TC of the (002 direction (TC(002 ≈ 3. The structural, morphological, and optical properties of the thin films as a function of aluminum content have been investigated using X-Ray Diffraction (XRD, Atomic Force Microscopy (AFM, and Scanning Electronic Microscopy (SEM. Waveguiding properties of the thin films have been also studied using m-lines spectroscopy. The results indicate that the films are monomodes at 632.8 nm with optical propagation optical losses estimated around 1.6 decibel per cm (dB/cm.

Radiation degradation and hemolytic toxicity evaluation of mono azo reactive dyes

International Nuclear Information System (INIS)

Saeed, Q.U.; Bhatti, I.A.; Ashraf, A.

2017-01-01

Monoazo reactive dyes have been synthesized and subjected to degradation before their application. Advanced oxidation process has been recognized as a promising radiation technology for the remediation of hazardous organic compounds. Radiation induced degradation of two mono azo reactive dyes have been tried at different absorbed dose, 5 kGy,10 kGy and 15 kGy. Aqueous solutions of these dyes were treated with gamma radiation using Cs 137 radiation source at Nuclear Institute of Agriculture and Biology (NIAB) Faisalabad. Dyes were evaluated spectrophotometrically by UV-visible and fourier transform infra red (FT-IR) spectroscopic techniques before and after irradiation to analyse their percentage decolorization and degradation. Maximum percentage decolorization of 93% and 63% was achieved for mono azo dyes D1 and D2 at 15 kGy absorbed dose. Toxicity study of these dyes was also tested by haemolytic activity assay. Percentage haemolytic activity of untreated dyes was found within permissible limit showing non toxicity of dye solutions. (author)

Simultaneous detection and removal of radioisotopes with modified alginate beads containing an azo-based probe using RGB coordinates

International Nuclear Information System (INIS)

Jo, Ara; Jang, Geunseok; Namgung, Ho; Kim, Choongho; Kim, Daigeun; Kim, Yujun; Kim, Jongho; Lee, Taek Seung

2015-01-01

Highlights: • Modified alginate with azo-based probe (ABO) was synthesized by a reaction between sodium alginate and azo-based probe (BO2). • BO2 was found to be a good probe molecule for radioisotopes using colorimetric analysis. • Detection of Co 2+ and Sr 2+ was mainly carried out via interaction between BO2 and metal ions. • Simultaneous removal of radioisotopes was assessed by the ion-exchange of carboxylate groups in sodium alginate. • The alginate beads with dual functions of detection and removal of metal ions are successfully accomplished. - Abstract: We prepared alginate beads that were modified with an azo-based probe molecule to monitor simultaneously the removal (by alginate) and probing (by the azo-probe molecule) of radioisotopes such as cobalt, strontium, and cesium ions. As an azo-probe molecule, Basic Orange 2 (BO2) was immobilized to the alginate bead. The BO2 in aqueous solution exhibited a slight red shift in absorption with a change in color from orange to dark orange upon addition of cobalt and strontium ions. In contrast, the color of BO2 did not change upon exposure to cesium ions. Thus, the covalently embedded BO2 in alginate beads could adsorb cobalt and strontium ions resulting in recognizable color change of the beads, which was induced by the formation of a complex between BO2 and metal ions. The color changes of the beads in the presence of metal ions were determined quantitatively using RGB color coordinate values. In addition to effectively removing metal ions, the colorimetric coordinate method provides a convenient and simple sensing technique for naked-eye metal ion detection.

Picric acid sensing and capture by a sterically encumbered azo ...

Indian Academy of Sciences (India)

Dhananjayan Kaleeswaran

2018-01-25

Jan 25, 2018 ... above observations in mind, here we demonstrate how the presence of bulky ... can affect the azo-polymerization process, PNACs sens- ing ability and CO2 uptake ... on a JEOL model JSM-7600F electron microscope, operat- ing at the .... i PrTAPB is flanked by two isopropyl groups and hence results in a ...

Transport behaviors of anionic azo dyes at interface between surfactant-modified flax shives and aqueous solution: Synchrotron infrared and adsorption studies

Energy Technology Data Exchange (ETDEWEB)

Wang, Wenxia [MOE Key Laboratory of Resources and Environmental Systems Optimization, Institute for Energy, Environment and Sustainability Research, UR-NCEPU, North China Electric Power University, Beijing, 102206 (China); Huang, Guohe, E-mail: huang@iseis.org [MOE Key Laboratory of Resources and Environmental Systems Optimization, Institute for Energy, Environment and Sustainability Research, UR-NCEPU, North China Electric Power University, Beijing, 102206 (China); An, Chunjiang; Xin, Xiaying [Institute for Energy, Environment and Sustainable Communities, University of Regina, Regina, S4S 0A2 (Canada); Zhang, Yan [MOE Key Laboratory of Resources and Environmental Systems Optimization, Institute for Energy, Environment and Sustainability Research, UR-NCEPU, North China Electric Power University, Beijing, 102206 (China); Liu, Xia [Canadian Light Source, Saskatoon, S7N 2V3 (Canada)

2017-05-31

Highlights: • Surfactant modified flax shives for removing anionic azo dyes. • The equilibrium and kinetic studies for the adsorption of anionic azo dyes. • The migration patterns of dye pollutants at flax shive-water interface. • New insights from synchrotron infrared-assisted characterization. • Potential as biomass adsorbent for the removal of dyes from wastewater. - Abstract: From the viewpoint of sustainability, biomass adsorbent has a high potential in pollution control and there is an emerging interest to investigate the behaviors of pollutants at the interface between biomass adsorbent and solution. This study investigated the performance of cetyltrimethylammonium bromide surfactant-modified flax shives (MFS) for removal of anionic azo dyes from aqueous solution. The equilibrium and kinetic analysis for the adsorption of Acid Orange 7 (AO-7), Acid Red 18 (AR-18) and Acid Black 1 (AB-1) on MFS were conducted. The surface of MFS was characterized by synchrotron infrared and SEM analysis. The absorbed amount of three anionic azo dyes varied with the change of adsorbent dosage, pH and ionic strength. The adsorption isotherm data well fit to the Langmuir model. The adsorption process followed the pseudo-second-order kinetics and the liquid film diffusion models. Thermodynamic studies indicated that the adsorption of three anionic azo dyes was spontaneous. The adsorption of AR-18 and AB-1 onto MFS was endothermic while the adsorption of AO-7 was exothermic. The results can help better understand the behaviors of organic pollutants at biomass adsorbent-water interface. They also present the potential of using MFS as a suitable adsorbent for the removal of anionic azo dyes from wastewater.

Transport behaviors of anionic azo dyes at interface between surfactant-modified flax shives and aqueous solution: Synchrotron infrared and adsorption studies

International Nuclear Information System (INIS)

Wang, Wenxia; Huang, Guohe; An, Chunjiang; Xin, Xiaying; Zhang, Yan; Liu, Xia

2017-01-01

Highlights: • Surfactant modified flax shives for removing anionic azo dyes. • The equilibrium and kinetic studies for the adsorption of anionic azo dyes. • The migration patterns of dye pollutants at flax shive-water interface. • New insights from synchrotron infrared-assisted characterization. • Potential as biomass adsorbent for the removal of dyes from wastewater. - Abstract: From the viewpoint of sustainability, biomass adsorbent has a high potential in pollution control and there is an emerging interest to investigate the behaviors of pollutants at the interface between biomass adsorbent and solution. This study investigated the performance of cetyltrimethylammonium bromide surfactant-modified flax shives (MFS) for removal of anionic azo dyes from aqueous solution. The equilibrium and kinetic analysis for the adsorption of Acid Orange 7 (AO-7), Acid Red 18 (AR-18) and Acid Black 1 (AB-1) on MFS were conducted. The surface of MFS was characterized by synchrotron infrared and SEM analysis. The absorbed amount of three anionic azo dyes varied with the change of adsorbent dosage, pH and ionic strength. The adsorption isotherm data well fit to the Langmuir model. The adsorption process followed the pseudo-second-order kinetics and the liquid film diffusion models. Thermodynamic studies indicated that the adsorption of three anionic azo dyes was spontaneous. The adsorption of AR-18 and AB-1 onto MFS was endothermic while the adsorption of AO-7 was exothermic. The results can help better understand the behaviors of organic pollutants at biomass adsorbent-water interface. They also present the potential of using MFS as a suitable adsorbent for the removal of anionic azo dyes from wastewater.

Decolorization of two azo dyes using marine Lysobacter sp. T312D9

Directory of Open Access Journals (Sweden)

Khouloud M. I. B.

2013-01-01

Full Text Available Aims: Novel azo dye-degrading bacterium T312D9 strain has been isolated from Abou Quir Gulf, Alexandria, Egypt. Methodology and Results: The identification of the isolate by 16S rRNA gene sequencing revealed to be Lysobacter sp. This marine ecofriendly isolate was exploited for its ability to degrade two synthetic azo dyes considered as detrimental pollutants from industrial effluents: congo red and methyl red. Using different dye concentrations showed the highest metabolic activity for complete degradation obtained from 100 to 500 mg/L within 30 h under static condition, also, sustaining higher dye loading of 1 g/L was carried out. The significant induction of enzymes NADH - 2,6-dichloroindophenol (NADH-DCIP reductase and tyrosinaseindicated their prominent role in dye degradation. The biodegradation of two azo dyes were analyzed by gas chromatographicmass spectrum analysis (GC-MS and Fourier transform infrared spectroscopy (FTIR before and after treatment. Toxicity study revealed the much less toxic nature of the metabolites produced after complete decolorization. Conclusion, significance and impact of study: Lysobacter sp T312D9 represent an inexpensive and promising marine bacteria for removal of both methyl and congo red. High sustainable metabolic activity for biodegradation under static condition. NADHDCIPreductase and tyrosinase were significantly induced during biodegradation of dyes. The obtained metabolites revealed to beless toxic in nature which offers a practical biological treatment.

Trans fatty acid isomers and the trans-9/trans-11 index in fat containing foods

Science.gov (United States)

Kuhnt, Katrin; Baehr, Melanie; Rohrer, Carsten; Jahreis, Gerhard

2011-01-01

To determine trans fatty acid (TFA) distribution of contemporary foods, especially regarding individual trans octadecenoic acids (trans C18:1), 339 German foods of six categories (semi-solid fats, deep-fried potato products, bakery products, confectioneries, instant products and butter) were analysed using two GC methods. Results showed a high variation of TFA content between and within the categories containing between 0 and 40.5% of FAME except in butter, which is a source of natural TFA. The mean TFA values were below 2.0% of FAME, however, bakery products contained 4.5% and butter fat 3.2%, respectively. In addition, the distribution of individual trans C18:1 differed. In samples containing ruminant fat (butter and various confectioneries), vaccenic acid (t11-C18:1, t11) predominated, while in foods containing industrially hydrogenated fats, elaidic acid (trans-9, t9-) and t10-C18:1 were the major trans isomers.. This was reflected by a low t9/t11 index of 0.3 and 0.5 in butter and ruminant fat containing confectioneries, respectively, whilst the highest index was observed in shortenings and deep-fried potato products at 5.2 and 6.8, respectively. In conclusion, the TFA content of foods available on the German market is generally declining, but substantial variations are present. The t9/t11 index could be used as an indicator to determine ruminant fat. Practical applications: A number of studies provide evidence that a high TFA intake, particularly of industrial origin, adversely affects human health. The TFA content of foods could be reduced due to the introduction of several mandatory regulations and modifications regarding the hydrogenation process of oils. The most abundant dietary TFA are the isomers of trans C18:1. Unfortunately, the differentiation of these isomers is not yet very common, though the trans C18:1 profile differs depending on its origin (bacterial hydrogenation in the rumen or industrial hydrogenation). To date, data for TFA content

Spectroscopic and theoretical study of the "azo"-dye E124 in condensate phase: evidence of a dominant hydrazo form.

Science.gov (United States)

Almeida, Mariana R; Stephani, Rodrigo; Dos Santos, Hélio F; de Oliveira, Luiz Fernando C

2010-01-14

Spectroscopic techniques, including Raman, IR, UV/vis, and NMR were used to characterize the samples of the azo dye Ponceau 4R (also known as E124, New Coccine; Cochineal Red; C.I. no. 16255; Food Red No. 102), which is 1,3-naphthalenedisulfonic acid, 7-hydroxy-8-[(4-sulfo-1-naphthalenyl) azo] trisodium salt in aqueous solution and solid state. In addition, first principle calculations were carried out for the azo (OH) and hydrazo (NH) tautomers in order to assist in the assignment of the experimental data. The two intense bands observed in the UV/vis spectrum, centered at 332 and 507 nm, can be compared to the calculated values at 296 and 474 nm for azo and 315 and 500 nm for hydrazo isomer, with the latter in closer agreement to the experiment. The Raman spectrum is quite sensitive to tautomeric equilibrium; in solid state and aqueous solution, three bands were observed around 1574, 1515, and 1364 cm(-1), assigned to mixed modes including deltaNH + betaCH + nuCC, deltaNH + nuC horizontal lineO + nuC horizontal lineN + betaCH and nuCC vibrations, respectively. These assignments are predicted only for the NH species centered at 1606, 1554, and 1375 cm(-1). The calculated Raman spectrum for the azo (OH) tautomer showed two strong bands at 1468 (nuN = N + deltaOH) and 1324 cm(-1) (nuCC + nuC-N), which were not obtained experimentally. The (13)C NMR spectrum showed a very characteristic peak at 192 ppm assigned to the carbon bound to oxygen in the naphthol ring; the predicted values were 165 ppm for OH and 187 for NH isomer, supporting once again the predominance of NH species in solution. Therefore, all of the experimental and theoretical results strongly suggest the food dye Ponceau 4R or E124 has a major contribution of the hydrazo structure instead of the azo form as the most abundant in condensate phase.

Oxygen configurations in silica

International Nuclear Information System (INIS)

Chelikowsky, James R.; Chadi, D. J.; Binggeli, N.

2000-01-01

We propose a transition state for oxygen in silica. This state is produced by the insertion of an oxygen molecule into the Si-O-Si bond, i.e., it consists of producing a Si-O-O-O-Si bond. This state allows molecular oxygen diffusion in silica without breaking the molecular O 2 bond and it is energetically more stable than a peroxy configuration. This configuration may allow for exchange of molecular oxygen with the oxygen in the silica framework. (c) 2000 The American Physical Society

Effect of Trans, Trans-Farnesol on Pseudogymnoascus destructans and Several Closely Related Species.

Science.gov (United States)

Raudabaugh, Daniel B; Miller, Andrew N

2015-12-01

Bat white-nose syndrome, caused by the psychrophilic fungus Pseudogymnoascus destructans, has dramatically reduced the populations of many hibernating North American bat species. The search for effective biological control agents targeting P. destructans is of great importance. We report that the sesquiterpene trans, trans-farnesol, which is also a Candida albicans quorum sensing compound, prevented in vitro conidial germination for at least 14 days and inhibited growth of preexisting hyphae of five P. destructans isolates in filtered potato dextrose broth at 10 °C. Depending on the inoculation concentrations, both spore and hyphal inhibition occurred upon exposure to concentrations as low as 15-20 µM trans, trans-farnesol. In contrast, most North American Pseudogymnoascus isolates were more tolerant to the exposure of trans, trans-farnesol. Our results suggest that some Candida isolates may have the potential to inhibit the growth of P. destructans and that the sesquiterpene trans, trans-farnesol has the potential to be utilized as a biological control agent.

trans-[Pt(BCat')Me(PCy3)2]: an experimental case study of reductive elimination processes in Pt-Boryls through associative mechanisms.

Science.gov (United States)

Braunschweig, Holger; Bertermann, Rüdiger; Brenner, Peter; Burzler, Michael; Dewhurst, Rian D; Radacki, Krzysztof; Seeler, Fabian

2011-10-10

A stable trans-(alkyl)(boryl) platinum complex trans-[Pt(BCat')Me(PCy(3))(2)] (Cat'=Cat-4-tBu; Cy=cyclohexyl=C(6)H(11)) was synthesised by salt metathesis reaction of trans-[Pt(BCat')Br(PCy(3))(2)] with LiMe and was fully characterised. Investigation of the reactivity of the title compound showed complete reductive elimination of Cat'BMe at 80 °C within four weeks. This process may be accelerated by the addition of a variety of alkynes, thereby leading to the formation of the corresponding η(2) -alkyne platinum complexes, of which [Pt(η(2)-MeCCMe)(PCy(3))(2)] was characterised by X-ray crystallography. Conversion of the trans-configured title compound to a cis derivative remained unsuccessful due to an instantaneous reductive elimination process during the reaction with chelating phosphines. Treatment of trans-[Pt(BCat')Me(PCy(3))(2)] with Cat(2)B(2) led to the formation of CatBMe and Cat'BMe. In the course of further investigations into this reaction, indications for two indistinguishable reaction mechanisms were found: 1) associative formation of a six-coordinate platinum centre prior to reductive elimination and 2) σ-bond metathesis of B-B and C-Pt bonds. Mechanism 1 provides a straightforward explanation for the formation of both methylboranes. Scrambling of diboranes(4) Cat(2)B(2) and Cat'(2)B(2) in the presence of [Pt(PCy(3))(2)], fully reductive elimination of CatBMe or Cat'BMe from trans-[Pt(BCat')Me(PCy(3))(2)] in the presence of sub-stoichiometric amounts of Cat(2)B(2), and evidence for the reversibility of the oxidative addition of Cat(2)B(2) to [Pt(PCy(3))(2)] all support mechanism 2, which consists of sequential equilibria reactions. Furthermore, the solid-state molecular structure of cis-[Pt(BCat)(2)(PCy(3))(2)] and cis-[Pt(BCat')(2)(PCy(3))(2)] were investigated. The remarkably short B-B separations in both bis(boryl) complexes suggest that the two boryl ligands in each case are more loosely bound to the Pt(II) centre than in related bis

Analytical procedures for the determination of disperse azo dyes

Energy Technology Data Exchange (ETDEWEB)

Betowski, L.D.; Jones, T.L. (Environmental Protection Agency, Las Vegas, NV (USA)); Munslow, W.; Nunn, N.J. (Lockheed Engineering and Management Services Co., Las Vegas, NV (USA))

1988-09-01

Disperse Blue 79 is the most widely-used azo dye in the US. Its economic importance for the dye industry and textile industry is very great. Because of its use and potential for degradation to aromatic amines, this compound has been chosen for testing by the Interagency Testing Committee. The authors laboratory has been developing methods for the analytical determination of Disperse Blue 79 and any possible degradation products in wastewater. This work has been taking place in conjunction with the study of the fate of azo dyes in the wastewater treatment processes by the Water Engineering Research Laboratory of the US EPA in Cincinnati. There were various phases for this analytical development. The first step involved purifying the commercial material or presscake to obtain a standard for quantitative determination. A combination of HPLC, TLC and mass spectrometric methods was used to determine purity after extraction and column cleanup. Phase two involved the extraction of the dye from the matrices involved. The third phase was the actual testing of Disperse Blue 79 in the waste activated sludge system and anaerobic digester. Recovery of the dye and any degradation products at each sampling point (e.g., secondary effluent, waste activated sludge) was the goal of this phase.

Abatement of Azo Dye from Wastewater Using Bimetal-Chitosan

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Ghorban Asgari

2013-01-01

Full Text Available We introduce a new adsorbent, bimetallic chitosan particle (BCP that is successfully synthesized and applied to remove the orange II dye from wastewater. The effects of pH, BCP quantity, and contact time are initially verified on the basis of the percentage of orange II removed from the wastewater. Experimental data reveal that the Cu/Mg bimetal and chitosan have a synergistic effect on the adsorption process of the adsorbate, where the dye adsorption by Cu/Mg bimetal, chitosan alone, and bimetal-chitosan is 10, 49, and 99.5%, respectively. The time required for the complete decolorization of orange II by 1 mg/L of BCP is 10 min. The Langmuir model is the best fit for the experimental data, which attains a maximum adsorption capacity of 384.6 mg/g. The consideration of the kinetic behavior indicates that the adsorption of orange II onto the BCP fits best with the pseudo-second-order and Elovich models. Further, the simulated azo dye wastewater can be effectively treated using a relatively low quantity of the adsorbent, 1 mg/L, within a short reaction time of 20 min. Overall, the use of BCP can be considered a promising method for eliminating the azo dye from wastewater effectively.

Photoinduced critical opalescence and reversible all-optical switching in photosensitive liquid crystals

International Nuclear Information System (INIS)

Tabiryan, Nelson V.; Serak, Svetlana V.; Grozhik, Vladimir A.

2003-01-01

We present the results of a study of the critical opalescence that is observed as a result of reversible trans-cis photoisomerization in the vicinity of photoinduced isothermal phase transitions in azobenzene liquid crystals (azo LCs). The opalescence is caused by the generation of randomly oriented microdomains and microdroplets of isotropic phase in the illuminated area of the azo LC. Transformations between the strongly light-scattering nematic phase and the transparent isotropic phase of the azo LC are induced all-optically by combination of green (λ=532 nm) and violet (λ=409 nm) laser beams

Photoinduced critical opalescence and reversible all-optical switching in photosensitive liquid crystals

Science.gov (United States)

Tabiryan, Nelson V.; Serak, Svetlana V.; Grozhik, Vladimir A.

2003-03-01

We present the results of a study of the critical opalescence that is observed as a result of reversible trans-cis photoisomerization in the vicinity of photoinduced isothermal phase transitions in azobenzene liquid crystals (azo LCs). The opalescence is caused by the generation of randomly oriented microdomains and microdroplets of isotropic phase in the illuminated area of the azo LC. Transformations between the strongly light-scattering nematic phase and the transparent isotropic phase of the azo LC are induced all-optically by combination of green (λ=532 nm) and violet (λ=409 nm) laser beams.

Separation of thorium, uranium and rare-earth elements with 2-[(2-arsenophenyl)-azo]-1,8-dihydroxy-7-[(2,4,6-tribromophenyl)azo]-naphthalene-3,6-disulfonic acid by capillary electrophoresis

International Nuclear Information System (INIS)

Liu, Bi-feng; Liu, Liang-bin; Cheng, Jie-ke

1998-01-01

The separation of thorium, uranium and rare-earth elements (RE) as their 2-[(2-arsenophenyl)-azo]-1,8-dihydroxy-7-[(2,4,6-tribromophenyl)azo]-naphthalene-3,6-disulfonic acid complexes by capillary electrophoresis with direct UV-Vis detection is presented in this paper. The influences of pH value and concentration of electrolyte, voltage and surfactant on separation were investigated and optimized. Under the selected conditions (30mM NaAc-HCl buffer containing 0.5mM cetyltrimethylammonium bromide and 0.2mM chelating reagent, pH 4.30, 12KV, 635nm as detection wavelength), the coexisted ions were separated within 4min, and limits of detection of 37, 39, 199μgl -1 for RE, thorium, uranium with a linear dynamic range of over 2 orders of magnitude were achieved, respectively

Studies on photofading and stable free radical formation in reactive dyed cellulosic systems under their exposure to light

International Nuclear Information System (INIS)

Remi, E.; Horvath, O.; Vig, A.; Aranyosi, P.; Rusznak, I.

1996-01-01

In light exposed systems of cotton and C.I. Reactive Red 3, C.I. Reactive Black 5 and C.I. Direct Blue 78 azo dyes respectively, generated stable free radicals could be detected. The observed hyperfine splitting of ESR spectra suggest the free radical are formed in the chromophore. Based upon the calculated g-values the location of the generated unpaired electron could be assumed on one of the C atoms of the dye molecule. (author)

Evaluation of the structural, optical and electrical properties of AZO thin films prepared by chemical bath deposition for optoelectronics

Science.gov (United States)

Kumar, K. Deva Arun; Valanarasu, S.; Rosario, S. Rex; Ganesh, V.; Shkir, Mohd.; Sreelatha, C. J.; AlFaify, S.

2018-04-01

Aluminum doped zinc oxide (AZO) thin films for electrode applications were deposited on glass substrates using chemical bath deposition (CBD) method. The influence of deposition time on the structural, morphological, and opto-electrical properties of AZO films were investigated. Structural studies confirmed that all the deposited films were hexagonal wurtzite structure with polycrystalline nature and exhibited (002) preferential orientation. There is no other impurity phases were detected for different deposition time. Surface morphological images shows the spherically shaped grains are uniformly arranged on to the entire film surface. The EDS spectrum confirms the presence of Zn, O and Al elements in deposited AZO film. The observed optical transmittance is high (87%) in the visible region, and the calculated band gap value is 3.27 eV. In this study, the transmittance value is decreased with increasing deposition time. The room temperature PL spectrum exposed that AZO thin film deposited at (60 min) has good optical quality with less defect density. The minimum electrical resistivity and maximum carrier concentration values were observed as 8.53 × 10-3(Ω cm) and 3.53 × 1018 cm-3 for 60 min deposited film, respectively. The obtained figure of merit (ϕ) value 3.05 × 10-3(Ω/sq)- 1 is suggested for an optoelectronic device.

Tunable Cascade Reaction of Aryl Diazonium Salts and Trialkylamine: Synthesis of Monofluorinated Arylhydrazones and gem-Difluorinated Azo Compounds.

Science.gov (United States)

Guo, Rui; Zhang, Zhengjuan; Shi, Feng; Tang, Pingping

2016-03-04

The first example of a mild and tunable cascade reaction of aryl diazonium salts and trialkylamine in the presence of Selectfluor to prepare monofluorinated arylhydrazones and gem-difluorinated azo compounds without metal has been explored. In the presence of H2O, the monofluorinated arylhydrazones were observed in moderate to good yield. In the absence of H2O, the gem-difluorinated azo compounds were obtained. The fluorinated arylhydrazones were utilized to synthesize fluorinated pyrazoles and other nitrogen-containing compounds.

Synthesis, characterization and biological profile of metal and azo-metal complexes of embelin

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R. Aravindhan

2014-12-01

Full Text Available The present study emphasizes synthesis and bioprofiling of embelin, embelin-metal (EM and embelin-azo-metal (EAM complexes in detail. EM complexes were prepared using pure embelin and d-block transition elements, namely Mn, Fe, Co, Ni, Cu, and Zn. Similarly, EAM complexes were synthesized using phenyl azo-embelin with the said transition metals. Embelin, EM, and EAM complexes were subjected to ultra violet visible spectroscopy, Fourier transform infrared spectroscopy, nuclear magnetic resonance, electrospray ionization mass spectrometry, thermogravimetric analysis, carbon hydrogen nitrogen sulfur analysis. With regard to bioprofiling, the test complexes were studied for the antioxidant and antimicrobial activities. Results revealed that the prepared EM and EAM complexes form octahedral complexes with embelin with the yield in the range of 45–75%. All the instrumental analyses authenticate the interaction of metals with bidentate embelin through its enolic and quinonic oxygen atoms as [M(Emb2(H2O2]H2O and [M(Emb-Azo2(H2O2]. The antioxidant profile studies suggested that upon complexation with metals, the free radical scavenging activity of embelin reduced significantly. But, with regard to antimicrobial activity, cobalt and nickel embelin complexes displayed>80% growth inhibition in comparison with embelin alone. The hemolytic activity studies suggested that both embelin and the metal complexes are non-hemolytic. The reason for the reduction in antioxidant and an increase in antimicrobial activities were discussed in detail.

Photocatalytic oxidation of a reactive azo dye and evaluation of the ...

African Journals Online (AJOL)

The purpose of this study was to investigate the photocatalytic oxidation of a reactive azo dye and determine the improvement in the biodegradability when photocatalytic oxidation was used as a pretreatment step prior to biological treatment. The results obtained from the experiments adding H2O2/TiO2 show that the ...

Decolorization of Remazol Black-B azo dye in soil by fungi

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Azeem Khalid*, Sadia Batool, Muhammad Tariq Siddique, Zilli Huma Nazli, Riffat Bibi, Shahid Mahmood and Muhammad Arshad

2011-04-01

Full Text Available Textile industry is known to release huge amount of dyes in the water and soil environments during the dyeingprocess. The present study was planned with the aim to remove azo dye toxicants from the soil using fungal strains.The fungi were isolated by using Remazol Black-B azo dye as the sole source of C and N. Ten isolates were initiallyselected for testing their decolorization potential in the liquid medium. Three most effective strains were used tostudy the decolorization of Remazol Black-B in soil. The strain S4 was found to be very effective in removing thedye Remazol Black-B from liquid medium as well as in soil suspension. More than 95% decolorization by the strainS4 was observed in soil under optimal incubation conditions. Overall, the dye decolorization was maximum at 100mg dye kg-1 soil at pH 7-8 under static conditions. Glucose, moisture and aeration also affected the decolorizationefficacy of the fungal strain in soil. This study implies that fungi could be used for bioremediation of dyecontaminatedsites.

Digital photocontrol of the network of live excitable cells

Science.gov (United States)

Erofeev, I. S.; Magome, N.; Agladze, K. I.

2011-11-01

Recent development of tissue engineering techniques allows creating and maintaining almost indefinitely networks of excitable cells with desired architecture. We coupled the network of live excitable cardiac cells with a common computer by sensitizing them to light, projecting a light pattern on the layer of cells, and monitoring excitation with the aid of fluorescent probes (optical mapping). As a sensitizing substance we used azobenzene trimethylammonium bromide (AzoTAB). This substance undergoes cis-trans-photoisomerization and trans-isomer of AzoTAB inhibits excitation in the cardiac cells, while cis-isomer does not. AzoTAB-mediated sensitization allows, thus, reversible and dynamic control of the excitation waves through the entire cardiomyocyte network either uniformly, or in a preferred spatial pattern. Technically, it was achieved by coupling a common digital projector with a macroview microscope and using computer graphic software for creating the projected pattern of conducting pathways. This approach allows real time interactive photocontrol of the heart tissue.

Perspectives d'amélioration du conseil prévisionnel de fertilisation azotée à la parcelle en Wallonie par l'utilisation du logiciel AzoFert®

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Abras, M.

2013-01-01

Full Text Available Prospects for improving the provisional nitrogen fertilization recommendation at field scale in Wallonia using the AzoFert® software. The French software AzoFert® for nitrogen fertilization recommendation is currently under adaptation and validation for soil and climatic conditions in Wallonia by the CRA-W within the INTERREG IV project "SUN" (Sustainable Use of Nitrogen. This adaptation has raised the need for a change of values in the parameter tables and catalogs relating to meadow residues, crop residues, catch crop practices, crops, organic amendments and soil type. Data from 25 trials of increasing nitrogen fertilizer rates conducted by CRA-W between 1996 and 2011 in cereal, potato and vegetable crops located on loam and sandy loam soil were used to validate the AzoFert® software adapted for Wallonia. The difference between nitrogen rates recommended on the one hand by AzoFert® or Azobil® (software currently used in the reference lab for Nitrate [Requasud] at CRA-W and the optimal dose of nitrogen fertilizer assessed in each trial on the other hand shows that, in most cases, AzoFert® gives a recommendation closer to the optimum than Azobil®. The nitrogen uptake measured in the plants collected in the unfertilized control plot also shows a higher correlation with nitrogen supply from the soil assessed by AzoFert® than for plants assessed by Azobil®. The more accurate estimate of the mineralization of organic sources, probably linked to the dynamic soil nitrogen supply approach integrated into AzoFert®, may explain the gain in the greater accuracy of the AzoFert® recommendation in comparison with that of Azobil®.

FACILE SYNTHESIS OF 1-NAPHTHOL AZO DYES WITH NANO ...

African Journals Online (AJOL)

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a highly efficient and one pot synthesis of azo dyes based on 1-naphthol under ... known and were identified by comparison of their physical and spectroscopic data with those of ... δ: 16.15 (s, 1H), 8.41 (d, J = 7.6 Hz, 1 H), 8.33 (d, J = 8.8 Hz, 2H), 7.8 (d, .... 86. 81. 77. 70. 65. N2. + IO4. -. O2N. 2d. 96. 93. 90. 85. 79. 73. 69.

Green synthesis of palladium nanoparticles with carboxymethyl cellulose for degradation of azo-dyes

Energy Technology Data Exchange (ETDEWEB)

Li, Gang; Li, Yun; Wang, Zhengdong; Liu, Huihong, E-mail: huihongliu@126.com

2017-02-01

Palladium nanoparticles (PdNPs) were synthesized through friendly environmental method using PdCl{sub 2} and carboxymethyl cellulose (CMC) in an aqueous solution (pH 6) at controlled water bath (80 °C) for 30 min. CMC functioned as both reducing and stabilizing agent. The characterization through high resolution-transmission electron microscopic (HRTEM) and X-ray Fluorescence Spectrometry (XRF) inferred that the as-synthesized PdNPs were spherical in shape with a face cubic crystal (FCC) structure. The results from dynamic light scattering (DLS) suggested the PdNPs had the narrow size distribution with an average size of 2.5 nm. The negative zeta potential (−52.6 mV) kept the as-synthesized PdNPs stable more than one year. The PdNPs showed the excellent catalytic activity by reducing degradation of azo-dyes, such as p-Aminoazobenzene, acid red 66, acid orange 7, scarlet 3G and reactive yellow 179, in the present of sodium borohydride. - Highlights: • Green synthesis of palladium nanoparticles using carboxymethyl cellulose. • The synthesis of palladium nanoparticles were performed easily. • Carboxymethyl cellulose acts as both reducing and stabilization agents. • The as-synthesized palladium nanoparticles show excellent catalytic activity.

Effect of light and sweeteners on color in an amaretto-type liqueur.

Science.gov (United States)

Castañeda-Olivares, F; Pless, R C; González-Jasso, E

2010-01-01

Studies on the color loss in an amaretto-type liqueur under controlled light conditions showed a clear dependence of the decoloration rate on the light intensity, and complete color stability in the absence of light. The principal sweetener used in the preparation of the liqueur strongly affected the rate of color loss under irradiation, color stability being much greater for the formulations containing sucrose or no added sweetener instead of fructose 42. These differences were more pronounced in experiments conducted with chemically well-defined mixtures that contained either of the 2 azo dyes used in the coloration of the amaretto, tartrazine, and Allura Red, and various alternative sweeteners, in 28% (v/v) ethanol solution: D-fructose and, to a lesser extent, D-glucose, at concentrations of 14% (w/v), were effective in bringing about photodecoloration, while no color loss was detected in the presence of sucrose, or in the absence of any added sugar. The results are interpreted in terms of a redox reaction of reducing sugars with the diarylazo compounds, the function of the light being the conversion of the azo compound from the predominant trans configuration to the cis configuration, which on geometric grounds lends itself better to a concerted, cyclical redox reaction with the reducing sugar. © 2010 Institute of Food Technologists®

Fighting for Trans* Kids: Academic Parent Activism in the 21st Century

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Kimberley Manning

2015-12-01

Full Text Available In this article we explore some of the affective and ethical dimensions that we have faced as parent academic-activists seeking to understand and undo some of the structural transphobia that currently exists in Canadian society.  Informed by critical feminist, critical race and black feminist thought, trans* scholarship, queer theory, and anti-oppression analysis, we discuss how our academic-activism assumes complex configurations of privilege and vulnerability.

A New Nano Silica Gel Supported by Thionyl Chloride as a Solid Acid for the Efficient Diazotization of Aniline Derivatives: Application and Synthesis of Azo Dyes

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Mohammad Mirjalili

2012-01-01

Full Text Available A new nano silicagel supported by thionyl chloride as a solid acid was synthesized and used as a increasing the production yield of dye to affect the efficient diazotization of arylamines. The diazonium salts thus obtained were coupled, using standard experimental procedures, to anilines and naphthols to afford the requisite azo dyes in good yield. The diazotization and subsequent azo-coupling generated the related azo dyes at low temperature in short reaction times with a simple experimental procedure.

Trans-Cultural, Trans-Language Practices: Potentialities for Rethinking Doctoral Education Pedagogies

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Sarojni Choy

2017-01-01

Full Text Available Over the last decade, there has been a rapid increase in doctoral enrolments of Asian international students in Australian universities. While policies have been developed to meet the needs of these students, there seems to be some confusion around the terms internationalisation, globalisation, bi-cultural, inter-cultural, multi-cultural, and trans-cultural within these policies. In this paper, we define these terms and advocate for a policy position which orients to a futurist definition of culture. We then review the work of Michael Singh and his research team at Western Sydney University who have responded to this rapid increase in Asian international student doctoral enrolments in Australian universities by developing pedagogic principles around notions of trans-language and trans-cultural practices. In the final section of the paper, we then draw on our own experiences of doctoral supervision in Australian universities to reflect on our positioning within the pedagogic principles around trans-language and trans-cultural practices.

Synthesis, Structural Characterization and Antimicrobial Activity of Cu(II and Fe(III Complexes Incorporating Azo-Azomethine Ligand

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Mohammad Azam

2018-04-01

Full Text Available We are reporting a novel azo-azomethine ligand, HL and its complexes with Cu(II and Fe(III ions. The ligand and its complexes are characterized by various physico-chemical techniques using C,H,N analyses, FT-IR, 1H-NMR, ESI-MS and UV-Vis studies. TGA analyses reveal complexes are sufficiently stable and undergo two-step degradation processes. The redox behavior of the complexes was evaluated by cyclic voltammetry. Furthermore, the ligand and its complexes were tested for antimicrobial activity against bacterial and fungal strains by determining inhibition zone, minimal inhibitory concentration (MIC and minimal bactericidal concentration (MBC. The complexes showed moderate antimicrobial activity when tested against Gram +ve and Gram −ve bacterial strains. To obtain insights into the structure of ligand, DFT studies are recorded. The results obtained are quite close to the experimental results. In addition, the energy gap, chemical hardness, softness, electronegativity, electrophilic index and chemical potential were calculated using HOMO, LUMO energy value of ligand.

Synthesis and evaluation of mutual azo prodrug of 5-aminosalicylic acid linked to 2-phenylbenzoxazole-2-yl-5-acetic acid in ulcerative colitis

Directory of Open Access Journals (Sweden)

Jilani JA

2013-07-01

Full Text Available Jamal A Jilani,1 Maha Shomaf,2 Karem H Alzoubi3 1Department of Medicinal Chemistry and Pharmacognosy, Jordan University of Science and Technology, Irbid, Jordan; 2Department of Pathology, Jordan University, Amman, Jordan; 3Department of Clinical Pharmacy, Jordan University of Science and Technology, Irbid, Jordan Abstract: In this study, the syntheses of 4-aminophenylbenzoxazol-2-yl-5-acetic acid, (an analogue of a known nonsteroidal anti-inflammatory drug [NSAID] and 5-[4-(benzoxazol-2-yl-5-acetic acidphenylazo]-2-hydroxybenzoic acid (a novel mutual azo prodrug of 5-aminosalicylic acid [5-ASA] are reported. The structures of the synthesized compounds were confirmed using infrared (IR, hydrogen-1 nuclear magnetic resonance (1H NMR, and mass spectrometry (MS spectroscopy. Incubation of the azo compound with rat cecal contents demonstrated the susceptibility of the prepared azo prodrug to bacterial azoreductase enzyme. The azo compound and the 4-aminophenylbenzoxazol-2-yl-5-acetic acid were evaluated for inflammatory bowel diseases, in trinitrobenzenesulfonic acid (TNB-induced colitis in rats. The synthesized diazo compound and the 4-aminophenylbenzoxazol-2-yl-5-acetic acid were found to be as effective as 5-aminosalicylic acid for ulcerative colitis. The results of this work suggest that the 4-aminophenylbenzoxazol-2-yl-5-acetic acid may represent a new lead for treatment of ulcerative colitis. Keywords: benzoxazole acetic acid, azo prodrug, colon drug delivery

Electrochemical characteriztion of the bioanode during simultaneous azo dye decolorization and bioelectricity generation in an air-cathode single chambered microbial fuel cell

International Nuclear Information System (INIS)

Sun Jian; Hu Yongyou; Hou Bin

2011-01-01

To achieve high power output based on simultaneously azo dye decolorization using microbial fuel cell (MFC), the bioanode responses during decolorization of a representative azo dye, Congo red, were investigated in an air-cathode single chambered MFC using representative electrochemical techniques. It has been found that the maximum stable voltage output was delayed due to slowly developed anode potential during Congo red decolorization, indicating that the electrons recovered from co-substrate are preferentially transferred to Congo red rather than the bioanode of the MFC and Congo red decolorization is prior to electricity generation. Addition of Congo red had a negligible effect on the Ohmic resistance (R ohm ) of the bioanode, but the charge-transfer resistance (R c ) and the diffusion resistance (R d ) were significantly influenced. The R c and R d firstly decreased then increased with increase of Congo red concentration, probably due to the fact that the Congo red and its decolorization products can act as electron shuttle for conveniently electrons transfer from bacteria to the anode at low concentration, but result in accelerated consumption of electrons at high concentration. Cyclic voltammetry results suggested that Congo red was a more favorable electron acceptor than the bioanode of the MFC. Congo red decolorization did not result in a noticeable decrease in peak catalytic current until Congo red concentration up to 900 mg l -1 . Long-term decolorization of Congo red resulted in change in catalytic active site of anode biofilm.

Trans* Leadership.

Science.gov (United States)

Jourian, T J; Simmons, Symone L

2017-06-01

Focusing on emerging literature on trans* and gender-nonconforming students and their leadership, this chapter outlines the ways trans* students are engaged in leadership in educational institutions and outside of them and discusses implications for staff and faculty regarding how to support and engage these students and their leadership. © 2017 Wiley Periodicals, Inc., A Wiley Company.

Synthesis, characterization and photoinduction of optical anisotropy in liquid crystalline diblock azo-copolymers

NARCIS (Netherlands)

Forcen, P.; Oriol, L.; Sanchez, S.; Alcala, R.; Hvilsted, S.; Jankova, K.; Loos, J.

2007-01-01

Diblock copolymers with polymethyl methacrylate and side chain liquid crystalline (LC) azopolymethacrylate blocks were synthesized by atom transfer radical polymerization (ATRP). The azobenzene content in these copolymers ranges from 52 to 7 wt %. For an azo content down to 20% they exhibit a LC

Synthesis and characterization of Mg-based amorphous alloys and their use for decolorization of Azo dyes

International Nuclear Information System (INIS)

Iqbal, M; Wang, W H

2014-01-01

Mg-based alloys are light weight and have wide range of applications in the automotive industry. These alloys are widely used because of their very attractive physical and mechanical properties and corrosion resistance. The properties and applications can be further improved by changing the nature of materials from crystalline to amorphous. In this study, melt spun ribbons (MSRs) of Mg 70 Zn 25 Ca 5 Mg 68 Zn 27 Ca 5 alloys were prepared by melt spinning technique by using 3-4N pure metals. Characterization of the samples was done by X-ray diffraction (XRD), differential scanning calorimetry (DSC) and energy dispersive x-ray analyzer (EDAX). Microstructural investigations were conducted by using scanning electron microscopy (SEM), atomic force microscopy (AFM) as well as optical and stereo scan microscopy techniques. DSC results showed multistage crystallization. Activation energy was found to be 225 kJ/mol by Kissinger method indicating good thermal stability against crystallization. XRD, DSC, SEM and EDS (energy dispersive spectroscopy) results are agreed very well. In order to study decolorization, the MSRs of Mg 70 Zn 25 Ca 5 Mg 68 Zn 27 Ca 5 alloys were treated repeatedly with various azo dyes at room temperature. In order to compare the results, MSRs of amorphous Zr- and Ni-based metallic glasses were also treated. Reaction of MSRs with azo dyes results in their decolorization in a few hours. Decolorization of azo dyes takes place by introducing amorphous MSRs which results in breaking the -N=N- bonds that exist in dye contents. It is concluded that Mg-based alloys are useful for paint and dye industries and will be beneficial to control water pollution. Comparison of results showed that Mg-based alloys are more efficient than Zr- and Ni-based amorphous alloys for decolorization of azo dyes

The oxidation of acid azo dye AY 36 by a manganese oxide containing mine waste

International Nuclear Information System (INIS)

Clarke, Catherine E.; Kielar, Filip; Johnson, Karen L.

2013-01-01

Highlights: ► This study looks at the oxidative breakdown of the amine containing dye acid yellow 36 by a Mn oxide containing mine waste. ► The oxidation proceeds by successive one electron transfers between the dye molecule and the Mn oxide minerals. ► The initial decolorization of the dye is rapid, but does not involve the cleavage of the azo bond. -- Abstract: The oxidative breakdown of acid azo dye acid yellow 36 (AY 36) by a Mn oxide containing mine tailings is demonstrated. The oxidation reaction is pH dependent with the rate of decolorization increasing with decreasing pH. The oxidation reaction mechanism is initiated at the amino moiety and proceeds via successive, one electron transfers from the dye to the Mn oxide minerals. The reaction pathway involves the formation of a number of colorless intermediate products, some of which hydrolyze in a Mn oxide-independent step. Decolorization of the dye is rapid and is observed before the cleavage of the azo-bond, which is a slower process. The terminal oxidation products were observed to be p-benzoquinone and 3-hydroxybenzenesulfonate. The reaction order of the initial decolorization was determined to be pseudo fractional order with respect to pH and pseudo first order with respect to dye concentration and Mn tailings’ surface area

Biotransformation of trans-1-chloro-3,3,3-trifluoropropene (trans-HCFO-1233zd)

International Nuclear Information System (INIS)

Schmidt, Tobias; Bertermann, Rüdiger; Rusch, George M.; Tveit, Ann; Dekant, Wolfgang

2013-01-01

trans-1-Chloro-3,3,3-trifluoropropene (trans-HCFO-1233zd) is a novel foam blowing and precision cleaning agent with a very low impact for global warming and ozone depletion. trans-HCFO-1233zd also has a low potential for toxicity in rodents and is negative in genotoxicity testing. The biotransformation of trans-HCFO-1233zd and kinetics of metabolite excretion with urine were assessed in vitro and in animals after inhalation exposures. For in vitro characterization, liver microsomes from rats, rabbits and humans were incubated with trans-HCFO-1233zd. Male Sprague Dawley rats and female New Zealand White rabbits were exposed to 2,000, 5,000 and 10,000 ppm for 6 h and urine was collected for 48 h after the end of the exposure. Study specimens were analyzed for metabolites using 19 F NMR, LC-MS/MS and GC/MS. S-(3,3,3-trifluoro-trans-propenyl)-glutathione was identified as predominant metabolite of trans-HCFO-1233zd in all microsomal incubation experiments in the presence of glutathione. Products of the oxidative biotransformation of trans-HCFO-1233zd were only minor metabolites when glutathione was present. In rats, both 3,3,3-trifluorolactic acid and N-acetyl-(3,3,3-trifluoro-trans-propenyl)-L-cysteine were observed as major urinary metabolites. 3,3,3-Trifluorolactic acid was not detected in the urine of rabbits. Quantitation showed rapid excretion of both metabolites in both species (t 1/2 1/2 < 6 h). ► Glutathione adduct as predominant in vitro metabolite in all tested species. ► Toxic metabolites could not be detected in any great extent

Biotransformation of trans-1-chloro-3,3,3-trifluoropropene (trans-HCFO-1233zd)

Energy Technology Data Exchange (ETDEWEB)

Schmidt, Tobias [Institut für Toxikologie, Universität Würzburg, Versbacher Str. 9, 97078 Würzburg (Germany); Bertermann, Rüdiger [Institut für Anorganische Chemie, Universität Würzburg, Am Hubland, 97074 Würzburg (Germany); Rusch, George M.; Tveit, Ann [Honeywell, P.O. Box 1057, Morristown, NJ 07962-1057 (United States); Dekant, Wolfgang, E-mail: dekant@toxi.uni-wuerzburg.de [Institut für Toxikologie, Universität Würzburg, Versbacher Str. 9, 97078 Würzburg (Germany)

2013-05-01

trans-1-Chloro-3,3,3-trifluoropropene (trans-HCFO-1233zd) is a novel foam blowing and precision cleaning agent with a very low impact for global warming and ozone depletion. trans-HCFO-1233zd also has a low potential for toxicity in rodents and is negative in genotoxicity testing. The biotransformation of trans-HCFO-1233zd and kinetics of metabolite excretion with urine were assessed in vitro and in animals after inhalation exposures. For in vitro characterization, liver microsomes from rats, rabbits and humans were incubated with trans-HCFO-1233zd. Male Sprague Dawley rats and female New Zealand White rabbits were exposed to 2,000, 5,000 and 10,000 ppm for 6 h and urine was collected for 48 h after the end of the exposure. Study specimens were analyzed for metabolites using {sup 19}F NMR, LC-MS/MS and GC/MS. S-(3,3,3-trifluoro-trans-propenyl)-glutathione was identified as predominant metabolite of trans-HCFO-1233zd in all microsomal incubation experiments in the presence of glutathione. Products of the oxidative biotransformation of trans-HCFO-1233zd were only minor metabolites when glutathione was present. In rats, both 3,3,3-trifluorolactic acid and N-acetyl-(3,3,3-trifluoro-trans-propenyl)-L-cysteine were observed as major urinary metabolites. 3,3,3-Trifluorolactic acid was not detected in the urine of rabbits. Quantitation showed rapid excretion of both metabolites in both species (t{sub 1/2} < 6 h) and the extent of biotransformation of trans-HCFO-1233zd was determined as approximately 0.01% of received dose in rabbits and approximately 0.002% in rats. trans-HCFO-1233zd undergoes both oxidative biotransformation and glutathione conjugation at very low rates. The low extent of biotransformation and the rapid excretion of metabolites formed are consistent with the very low potential for toxicity of trans-HCFO-1233zd in mammals. - Highlights: ► No lethality and clinical signs were observed. ► Glutathione S-transferase and cytochrome P-450 dependent

Total aerobic destruction of azo contaminants with nanoscale zero-valent copper at neutral pH: promotion effect of in-situ generated carbon center radicals.

Science.gov (United States)

Dong, Guohui; Ai, Zhihui; Zhang, Lizhi

2014-12-01

In this study, nanoscale zero-valent copper (nZVC) was synthesized with a facile solvothermal method and used for the aerobic removal of azo contaminants at neutral pH for the first time. We found that both Cu(I) and OH generated during the nZVC induced molecular oxygen activation process accounted for the rapid total destruction of azo contaminants in the nZVC/Air system, where nZVC could activate molecular oxygen to produce H2O2, and also release Cu(I) to break the -NN- bond of azo contaminants via the sandmeyer reaction for the generation of carbon center radicals. The in-situ generated carbon center radicals would then react with OH produced by the Cu(I) catalyzed decomposition of H2O2, resulting in the generation of low molecular weight organic acids and their subsequent mineralization. The indispensible role of Cu(I) catalyzed sandmeyer reaction and the promotion effect of in-situ generated carbon center radicals on the rapid total destruction of azo contaminants in the nZVC/Air system were confirmed by gas chromatography-mass spectrometry analysis. This study can deepen our understanding on the degradation of organic pollutant with molecular oxygen activated by zero valent metal, and also provide a new method to remove azo contaminants at neutral pH. Copyright © 2014 Elsevier Ltd. All rights reserved.

Powdered activated carbon adsorption of two fishy odorants in water: Trans,trans-2,4-heptadienal and trans,trans-2,4-decadienal.

Science.gov (United States)

Li, Xin; Wang, Jun; Zhang, Xiaojian; Chen, Chao

2015-06-01

Powdered activated carbon (PAC) adsorption of two fishy odorants, trans,trans-2,4-heptadienal (HDE) and trans,trans-2,4-decadienal (DDE), was investigated. Both the pseudo first-order and the pseudo second-order kinetic models well described the kinetics curves, and DDE was more readily removed by PAC. In isotherm tests, both Freundlich and Modified Freundlich isotherms fitted the experimental data well. PAC exhibited a higher adsorption capacity for DDE than for HDE, which could be ascribed to the difference in their hydrophobicity. The calculated thermodynamic parameters (ΔG0, ΔH0, and ΔS0) indicated an exothermic and spontaneous adsorption process. PAC dosage, pH, and natural organic matter (NOM) presence were found to influence the adsorption process. With increasing PAC dosage, the pseudo first-order and pseudo second-order rate constants both increased. The value of pH had little influence on HDE or DDE molecules but altered the surface charge of PAC, and the maximum adsorption capacity occurred at pH9. The presence of NOM, especially the fraction with molecular weight less than 1k Dalton, hindered the adsorption. The study showed that preloaded NOM impaired the adsorption capacity of HDE or DDE more severely than simultaneously fed NOM did. Copyright © 2015. Published by Elsevier B.V.

Heterogeneous fenton degradation of azo dyes catalyzed by modified polyacrylonitrile fiber fe complexes: QSPR (quantitative structure peorperty relationship) study.

Science.gov (United States)

Li, Bing; Dong, Yongchun; Ding, Zhizhong

2013-07-01

The amidoximated polyacrylonitrile (PAN) fiber Fe complexes were prepared and used as the heterogeneous Fenton catalysts for the degradation of 28 anionic water soluble azo dyes in water under visible irradiation. The multiple linear regression (MLR) method was employed to develop the quantitative structure property relationship (QSPR) model equations for the decoloration and mineralization of azo dyes. Moreover, the predictive ability of the QSPR model equations was assessed using Leave-one-out (LOO) and cross-validation (CV) methods. Additionally, the effect of Fe content of catalyst and the sodium chloride in water on QSPR model equations were also investigated. The results indicated that the heterogeneous photo-Fenton degradation of the azo dyes with different structures was conducted in the presence of the amidoximated PAN fiber Fe complex. The QSPR model equations for the dye decoloration and mineralization were successfully developed using MLR technique. MW/S (molecular weight divided by the number of sulphonate groups) and NN=N (the number of azo linkage) are considered as the most important determining factor for the dye degradation and mineralization, and there is a significant negative correlation between MW/S or NN=N and degradation percentage or total organic carbon (TOC) removal. Moreover, LOO and CV analysis suggested that the obtained QSPR model equations have the better prediction ability. The variation in Fe content of catalyst and the addition of sodium chloride did not alter the nature of the QSPR model equations.

Synthesis and spectral studies of some novel coumarin based disperse azo dyes

International Nuclear Information System (INIS)

Amjad, R.; Khan, S.R.; Naeem, M.

2009-01-01

Synthesis of some novel coumarin based azo dyes was carried out by diazotization of heterocyclic amines using nitrosyl sulphuric acid and then coupling them with 7-hydroxy-4-methyl Coumarin. The synthesized dyes when applied on polyester fibers showed moderate to good light fastness and very good to excellent fastness to washing, rubbing, perspiration and sublimation. (author)

Preparation, spectral, X-ray powder diffraction and computational studies and genotoxic properties of new azo-azomethine metal chelates

Science.gov (United States)

Bitmez, Şirin; Sayin, Koray; Avar, Bariş; Köse, Muhammet; Kayraldız, Ahmet; Kurtoğlu, Mükerrem

2014-11-01

A new tridentate azo-azomethine ligand, N‧-[{2-hydroxy-5-[(4-nitrophenyl)diazenyl]phenyl}methylidene]benzohydrazidemonohydrate, (sbH·H2O) (1), is prepared by condensation of benzohydrazide and 2-hydroxy-5-[(4-nitrophenyl)diazenyl]benzaldehyde (a) with treatment of a solution of diazonium salt of p-nitroaniline and 2-hydroxybenzaldehyde in EtOH. The five coordination compounds, [Co(sb)2]·4H2O (2), [Ni(sb)2]·H2O (3), [Cu(sb)2]·4H2O (4), [Zn(sb)2]·H2O (5) and [Cd(sb)2]·H2O (6) are prepared by reacting the Co(II), Ni(II), Cu(II), Zn(II) and Cd(II) ions with the ligand. The structures of the compounds are elucidated from the elemental analyses data and spectroscopic studies. It is found the ligand acts as a tridentate bending through phenolic and carbonyl oxygens and nitrogen atom of the Cdbnd Nsbnd group similar to the most of salicylaldimines. Comparison of the infrared spectra of the ligand and its metal complexes confirm that azo-Schiff base behaves as a monobasic tridentate ligand towards the central metal ion with an ONO donor sequence. Upon complexation with the ligand, the Cd(II), and Zn(II) ions form monoclinic structures, while Co(II), Cu(II) and Ni(II) ions form orthorhombic structures. Quantum chemical calculations are performed on tautomers and its metal chelates by using DFT/B3LYP method. Most stable tautomer is determined as tautomer (1a). The geometrical parameters of its metal chelates are obtained as theoretically. The NLO properties of tautomer (1a) and its metal complexes are investigated. Finally, the ligand and its metal complexes are assessed for their genotoxicity.

Survey of the trans-resveratrol and trans-piceid content of cocoa-containing and chocolate products.

Science.gov (United States)

Hurst, W Jeffrey; Glinski, Jan A; Miller, Kenneth B; Apgar, Joan; Davey, Matthew H; Stuart, David A

2008-09-24

Dietary resveratrol (3,4',5-trihydroxystilbene) has been implicated in the health benefits associated with grapes and red wine, more specifically with potential benefits for metabolic syndrome, energy use, and increased endurance. Levels of trans-resveratrol and its glucoside, trans-piceid, were determined in 19 top selling commercially available cocoa-containing and chocolate products from the U.S. market. Amounts of trans-resveratrol and trans-piceid were closely correlated with the amount of nonfat cocoa solids (NFCS) in the cocoa-containing products. Among these products, trans-resveratrol levels were highest in cocoa powders (1.85 +/- 0.43 microg/g), followed by unsweetened baking chocolates (1.24 +/- 0.22), semisweet chocolate baking chips (0.52 +/- 0.14), dark chocolates (0.35 +/- 0.08), milk chocolates (0.10 +/- 0.05), and chocolate syrups (0.09 +/- 0.02). These cocoa-containing and chocolate products have about 3-5 times more trans-piceid than trans-resveratrol. Levels of trans-piceid were highest in the cocoa powders (7.14 +/- 0.80 microg/g), followed by unsweetened baking chocolates (4.04 +/- 0.14), semisweet chocolate baking chips (2.01 +/- 0.18), dark chocolates (1.82 +/- 0.36), milk chocolates (0.44 +/- 0.06), and chocolate syrups (0.35 +/- 0.06). On an equal weight basis, cocoa powder had about half as much trans-resveratrol as the average California red wine. On a per serving basis, cocoa-containing and chocolate products had less trans-resveratrol than red wine and grape juice but more than roasted peanuts. Overall, these cocoa-containing and chocolate products rank second after red wines and grape juice in foods with the highest levels of total trans-resveratrol in the diet.

Electrodegradation of Ponceau 2R using dimensionally-stable anodes and Ti/Pt

Energy Technology Data Exchange (ETDEWEB)

Ribeiro, Francisco Wirley Paulino; Oliveira, Sameque do Nascimento; Lima-Neto, Pedro de; Correia, Adriana Nunes, E-mail: adriana@ufc.br [Universidade Federal do Ceara, Fortaleza (UFC), CE (Brazil). Centro de Ciencias. Dept. de Quimica Analitica e Fisico-Quimica; Mascaro, Lucia Helena; Matos, Roberto de; Souza, Ernesto Chaves Pereira de [Universidade Federal de Sao Carlos (UFSC), SP (Brazil). Dept. de Quimica; Lanza, Marcos Roberto de Vasconcelos [Universidade de Sao Paulo (USP), Sao Carlos, SP (Brazil). Inst. de Quimica

2013-08-01

This paper reports the electrochemical degradation of the azo dye Ponceau 2R under galvanostatic electrolysis in the 1 to 200 mA cm{sup -2} range at room temperature using dimensionally-stable anodes of oxygen (DSA-O{sub 2}), chlorine (DSA-Cl{sub 2}) and a titanium electrode of platinum coated with platinum oxide (Ti/Pt). The methodology applied was efficient for removing the color of the Ponceau 2R and the highest percentage removal of total organic carbon was obtained at 200 mA cm{sup -2}. Despite not having been observed complete mineralization, approximately 80% removal of aromatic rings was estimated, resulting in drastic reduction of toxicity of the sample. (author)

Radiation resistance of organic azo dyes in aqueous solutions

International Nuclear Information System (INIS)

Khabarov, V.N.; Kozlov, L.L.

1987-01-01

The resistance to the action of the ionizing radiation of aqueous and aqueous-alcoholic solutions of organic mono- and diazo dyes was studied. The radiation chemical yield of decolorization of the dye, determined from the kinetic decolorization curves served as a quantitative criterion of the radiation resistance. The influence of pH, addition of ethanol, hydroquinone, thiourea, glucose and oxygen on the radiation resistance of the azo dyes was studied. An attempt was made to relate the efficiency of radiation decolorization to the chemical nature of the dye

Particle transort in field-reversed configurations

Energy Technology Data Exchange (ETDEWEB)

Tuszewski, M.; Linford, R.K.; Lipson, J.; Sgro, A.G.

1981-01-01

A field reversed configuration (FRC) is a compact toroid that contains no toroidal field. These plasmas are observed to be grossly stable for about 10-100 ..mu..sec. The lifetimes appear limited by an n = 2 rotational instability which may be caused by particle loss. Particle transport is therefore an important issue for these configurations. We investigate particle loss with a steady-state, 1-D model which approximates the experimental observation of elongated FRC equilibrium with about constant separatrix radius.

KINETIC BEHAVIOR OF SOME AZO DYES DECOLORIZATION BY VARIATION OF ZINC OXIDE AND TITANIUM DIOXIDE CONCENTRATIONS

Directory of Open Access Journals (Sweden)

Wallace J. C. da Silva

Full Text Available The decolorization of three monoazo dyes (acid orange 7, direct orange 34, and methyl orange, one diazo dye (direct yellow 86 and one tetraazo dye (direct red 80 were mediated by n-type semiconductors as ZnO and TiO2 under pseudo-first order conditions at 30 ºC. The decolorization rate constants of these azo dyes were determined, varying the semiconductor concentration for the majority of them from 1.0 to 10.0 g L-1. In general, the highest rate constants were displayed for ZnO. This work elucidates that the decolorization capacity depends on the charge, structure, and adsorption of the azo dye on the semiconductor surface as well as the agglomeration of the photocatalyst particles.

Which Parts of a Clinical Process EPR Needs Special Configuration

DEFF Research Database (Denmark)

Barlach, Anders; Simonsen, Jesper

2007-01-01

Subject: Which parts of an electronic patient record (EPR) can initially form a stable standard solution to be used by all clinicians? And which parts of an EPR can we predict needs initial as well as on-going re-configuration to meet the needs from diverse medical specialties. Purpose: To analyze...... which screen types in a clinical process that can be standard configured and which are subject to initial as well as on-going re-configuration. Methods and results: A pilot-project implementing a fully functional clinical process EPR was configured and used at a neurological ward, replacing all paper...... records 24/7. The analysis characterizes the different types of screens, a total of 243 included in the EPR solution. All screens have been extracted from the application and analyzed for changes – in total 222 changes. Discussion and conclusion: Most screens (87%) are very stable. Few (13%) are subjected...

Tautomeric preferences of the cis and trans isomers of axitinib

Science.gov (United States)

Mirzaei, M. Saeed; Taherpour, Avat Arman

2018-05-01

The tautomeric preferences of axitinib, a potent anticancer drug, as tyrosine kinase inhibitor have been investigated using quantum chemical calculations and docking methods. The energy differences between the two tautomers of trans-isomer are around 4 and 3 kcal mol-1 in vacuo and water, respectively, and for its cis-isomer (major photochemical isomerization product) this equilibrium reversed completely in favour of the second tautomer (not considered previously), which is about 7-8 kcal mol-1 more stable in both gas and aqueous media. The results indicate a very high activation energy for proton exchange for both [1,2] and [1,5] H-shift (around 50 kcal mol-1) in the gas phase, but inclusion of protic solvents (e.g. water) decrease this barrier to around 14 and 35 kcal mol-1 for the both hydrogen shift processes, respectively. In order to have better insight about the electronic structure of axitinib tautomers, the NBO, HOMO-LUMO, NICS and molecular electrostatic potential surfaces (MESP) calculations have been carried out. Docking investigations on the two more stable tautomers revealed that binding of the trans isomer of tautomer I to the active site of the receptor is the most favourable in the terms of energy and structure. This more stability could be attributed to the more hydrogen bonding of this tautomer with the protein residues in comparison to the second tautomer.

Simultaneous Decolorization and Biohydrogen Production from Xylose by Klebsiella oxytoca GS-4-08 in the Presence of Azo Dyes with Sulfonate and Carboxyl Groups

Science.gov (United States)

Cao, Ming-yue; Wang, Peng-tao; Wang, Shi; Yue, Ying-rong; Yuan, Wen-duo; Qiao, Wei-chuan; Wang, Fei

2017-01-01

ABSTRACT Biohydrogen production from the pulp and paper effluent containing rich lignocellulosic material could be achieved by the fermentation process. Xylose, an important hemicellulose hydrolysis product, is used less efficiently as a substrate for biohydrogen production. Moreover, azo dyes are usually added to fabricate anticounterfeiting paper, which further increases the complexity of wastewater. This study reports that xylose could serve as the sole carbon source for a pure culture of Klebsiella oxytoca GS-4-08 to achieve simultaneous decolorization and biohydrogen production. With 2 g liter−1 of xylose as the substrate, a maximum xylose utilization rate (URxyl) and a hydrogen molar yield (HMY) of 93.99% and 0.259 mol of H2 mol of xylose−1, respectively, were obtained. Biohydrogen kinetics and electron equivalent (e− equiv) balance calculations indicated that methyl red (MR) penetrates and intracellularly inhibits both the pentose phosphate pathway and pyruvate fermentation pathway, while methyl orange (MO) acted independently of the glycolysis and biohydrogen pathway. The data demonstrate that biohydrogen pathways in the presence of azo dyes with sulfonate and carboxyl groups were different, but the azo dyes could be completely reduced during the biohydrogen production period in the presence of MO or MR. The feasibility of hydrogen production from industrial pulp and paper effluent by the strain if the xylose is sufficient was also proved and was not affected by toxic substances which usually exist in such wastewater, except for chlorophenol. This study offers a promising energy-recycling strategy for treating pulp and paper wastewaters, especially for those containing azo dyes. IMPORTANCE The pulp and paper industry is a major industry in many developing countries, and the global market of pulp and paper wastewater treatment is expected to increase by 60% between 2012 and 2020. Such wastewater contains large amounts of refractory contaminants, such

Study on the enhanced and stable field emission behavior of a novel electrosprayed Al-doped ZnO bilayer film

KAUST Repository

Mahmood, Khalid; Munir, Rahim; Swain, Bhabani Sankar; Han, Gill Sang; Kim, Byeong Jo; Jung, Hyun Suk

2014-01-01

A novel electrosprayed bilayer film composed of an over-layer (L 2) of aluminium-doped ZnO (AZO) nanoflakes (NF-AZO) and a under-layer (L1) of AZO nanocrystallites structure (NC-AZO) named BL:NF/NC-AZO is studied as an excellent field-emitter. The XRD pattern demonstrated that the doped bilayer film has preferential growth along the c-axis with hexagonal wurtzite structure and the (0 0 2) peak shifted toward the larger angle side after doping. The lowest turn-on field of ∼2.8 V μm-1, highest emission current density of 1.95 mA cm-2 is obtained for BL:NF/NC-AZO under the field of 6.8 V μm-1 and as well as the highest field enhancement factor (β) is estimated to be 4370 ± 3, compared to pure ZnO bilayer film (BL:NF/NC-ZnO) and also better than NC-AZO film and possesses the excellent long term stability of emission current. The PL intensity of doped ZnO bilayer film is very much stronger than pure ZnO bilayer structure. The superior field emission properties are attributed to the better morphologies, Al-doping and better crystallinity of bilayer AZO films. © 2014 The Royal Society of Chemistry.

Homologous SV40 RNA trans-splicing: Special case or prime example of viral RNA trans-splicing?

Directory of Open Access Journals (Sweden)

Sushmita Poddar

2014-06-01

Full Text Available To date the Simian Virus 40 (SV40 is the only proven example of a virus that recruits the mechanism of RNA trans-splicing to diversify its sequences and gene products. Thereby, two identical viral transcripts are efficiently joined by homologous trans-splicing triggering the formation of a highly transforming 100 kDa super T antigen. Sequences of other viruses including HIV-1 and the human adenovirus type 5 were reported to be involved in heterologous trans-splicing towards cellular or viral sequences but the meaning of these events remains unclear. We computationally and experimentally investigated molecular features associated with viral RNA trans-splicing and identified a common pattern: Viral RNA trans-splicing occurs between strong cryptic or regular viral splice sites and strong regular or cryptic splice sites of the trans-splice partner sequences. The majority of these splice sites are supported by exonic splice enhancers. Splice sites that could compete with the trans-splicing sites for cis-splice reactions are weaker or inexistent. Finally, all but one of the trans-splice reactions seem to be facilitated by one or more complementary binding domains of 11 to 16 nucleotides in length which, however occur with a statistical probability close to one for the given length of the involved sequences. The chimeric RNAs generated via heterologous viral RNA trans-splicing either did not lead to fusion proteins or led to proteins of unknown function. Our data suggest that distinct viral RNAs are highly susceptible to trans-splicing and that heterologous viral trans-splicing, unlike homologous SV40 trans-splicing, represents a chance event.

DNA compaction by azobenzene-containing surfactant

International Nuclear Information System (INIS)

Zakrevskyy, Yuriy; Kopyshev, Alexey; Lomadze, Nino; Santer, Svetlana; Morozova, Elena; Lysyakova, Ludmila; Kasyanenko, Nina

2011-01-01

We report on the interaction of cationic azobenzene-containing surfactant with DNA investigated by absorption and fluorescence spectroscopy, dynamic light scattering, and atomic force microscopy. The properties of the surfactant can be controlled with light by reversible switching of the azobenzene unit, incorporated into the surfactant tail, between a hydrophobic trans (visible irradiation) and a hydrophilic cis (UV irradiation) configuration. The influence of the trans-cis isomerization of the azobenzene on the compaction process of DNA molecules and the role of both isomers in the formation and colloidal stability of DNA-surfactant complexes is discussed. It is shown that the trans isomer plays a major role in the DNA compaction process. The influence of the cis isomer on the DNA coil configuration is rather small. The construction of a phase diagram of the DNA concentration versus surfactant/DNA charge ratio allows distancing between three major phases: colloidally stable and unstable compacted globules, and extended coil conformation. There is a critical concentration of DNA above which the compacted globules can be hindered from aggregation and precipitation by adding an appropriate amount of the surfactant in the trans configuration. This is because of the compensation of hydrophobicity of the globules with an increasing amount of the surfactant. Below the critical DNA concentration, the compacted globules are colloidally stable and can be reversibly transferred with light to an extended coil state.

"There's no chasing involved": cis/trans relationships, "tranny chasers," and the future of a sex-positive trans politics.

Science.gov (United States)

Tompkins, Avery Brooks

2014-01-01

This article adds to a small, but growing, body of work on trans sexualities and partnerships, and provides a much-needed inquiry into the complex and contested politics of desire when we take trans identities, bodies, and sexualities into account. Using digital ethnographic data from YouTube videos along with in-person observational data from LGBTQ and trans conferences in the U.S., Tompkins argues that a sex-positive trans politics cannot emerge in trans and trans-allied communities if the rhetoric of the "tranny chaser" continues to inform discourses of desire and attraction to trans people.

Synthesis of silver nanoparticles using bacterial exopolysaccharide and its application for degradation of azo-dyes

Directory of Open Access Journals (Sweden)

Chinnashanmugam Saravanan

2017-09-01

Full Text Available In this study, the synthesis and characterization of exopolysaccharide-stabilized sliver nanoparticles (AgNPs was carried out for the degradation of industrial textile dyes. Characterization of AgNPs was done using surface plasmon spectra using UV–Vis spectroscopy, X-ray diffraction (XRD and Raman spectroscopy. The morphological nature of AgNPs was determined through transmission electron microscopy (TEM, scanning electron microscopy (SEM and atomic force microscopy (AFM, which indicated that the AgNPs were spherical in shape, with an average size of 35 nm. The thermal behaviour of AgNPs revealed that it is stable up to 437.1 °C and the required energy is 808.2J/g in TGA-DTA analysis. Ability of EPS stabilized AgNPs for degradation of azo dyes such as Methyl orange (MO and Congo red (CR showed that EPS stabilized AgNPs were found to be efficient in facilitating the degradation process of industrial textile dyes. The electron transfer takes place from reducing agent to dye molecule via nanoparticles, resulting in the destruction of the dye chromophore structure. This makes EPS-AgNPs a suitable, cheap and environment friendly candidate for biodegradation of harmful textile dyes.

Novel zinc(II)phthalocyanines bearing azo-containing schiff base: Determination of pKa values, absorption, emission, enzyme inhibition and photochemical properties

Science.gov (United States)

Kantar, Cihan; Mavi, Vildan; Baltaş, Nimet; İslamoğlu, Fatih; Şaşmaz, Selami

2016-10-01

Azo-containing schiff bases are well known and there are many studies about their various properties in literature. However, phthalocyanines bearing azo-containing schiff bases, their spectral, analytical and biological properties are unknown. Therefore, new zinc (II) phthalocyanines bearing azo-containing schiff base were synthesized and investigated to determine pKa values, absorption, emission, enzyme inhibition and photochemical properties. Emission spectra were reported and large Stokes shift values were determined for all compounds, indicating that all molecules exhibit excited state intramolecular proton transfer. These phthalocyanines were the first examples of phthalocyanine showing excited state intramolecular proton transfer. Singlet oxygen quantum yields of zinc (II) phthalocyanines were determined. pKa values and indicator properties of all compounds were investigated by potentiometry. All compounds were assayed for inhibitory activity against bovine milk xanthine oxidase and acetylcholinesterase enzyme in vitro. Compound 2 showed the high inhibitory effect against xanthine oxidase (IC50 = 0.24 ± 0.01 μM). However, phthalocyanine compounds did not show enzyme inhibitor behavior.

Quantum tunneling in real space: Tautomerization of single porphycene molecules on the (111) surface of Cu, Ag, and Au

Science.gov (United States)

Kumagai, Takashi; Ladenthin, Janina N.; Litman, Yair; Rossi, Mariana; Grill, Leonhard; Gawinkowski, Sylwester; Waluk, Jacek; Persson, Mats

2018-03-01

Tautomerization in single porphycene molecules is investigated on Cu(111), Ag(111), and Au(111) surfaces by a combination of low-temperature scanning tunneling microscopy (STM) experiments and density functional theory (DFT) calculations. It is revealed that the trans configuration is the thermodynamically stable form of porphycene on Cu(111) and Ag(111), whereas the cis configuration occurs as a meta-stable form. The trans → cis or cis → trans conversion on Cu(111) can be induced in an unidirectional fashion by injecting tunneling electrons from the STM tip or heating the surface, respectively. We find that the cis ↔ cis tautomerization on Cu(111) occurs spontaneously via tunneling, verified by the negligible temperature dependence of the tautomerization rate below ˜23 K. Van der Waals corrected DFT calculations are used to characterize the adsorption structures of porphycene and to map the potential energy surface of the tautomerization on Cu(111). The calculated barriers are too high to be thermally overcome at cryogenic temperatures used in the experiment and zero-point energy corrections do not change this picture, leaving tunneling as the most likely mechanism. On Ag(111), the reversible trans ↔ cis conversion occurs spontaneously at 5 K and the cis ↔ cis tautomerization rate is much higher than on Cu(111), indicating a significantly smaller tautomerization barrier on Ag(111) due to the weaker interaction between porphycene and the surface compared to Cu(111). Additionally, the STM experiments and DFT calculations reveal that tautomerization on Cu(111) and Ag(111) occurs with migration of porphycene along the surface; thus, the translational motion couples with the tautomerization coordinate. On the other hand, the trans and cis configurations are not discernible in the STM image and no tautomerization is observed for porphycene on Au(111). The weak interaction of porphycene with Au(111) is closest to the gas-phase limit and therefore the absence

TransAlta: More than a utility

International Nuclear Information System (INIS)

Mikalson, D.A.

1991-01-01

TransAlta Utilities Corporation is Canada's largest privately owned utility and is also a major coal mining company. In 1989, TransAlta produced 20.9% of all coal mined in Canada. A brief history of TransAlta is presented along with TransAlta's present coal operations and plans for the next three years. An overview is presented of how TransAlta Fuel Supply is organized to utilize contracted mining operation, engineering and environmental services and in-house capabilities. Recent strategic initiatives to improve organizational efficiency and the mining operations are discussed. These range from developing a common departmental vision to modifying major mining equipment. TransAlta's proactive role in clean coal combustion such as low NOx-SOx burner, integrated combined cycle gasification, and other energy research projects is reviewed. A summary is provided of recent participation of TransAlta in environmental management initiatives. Recent successes of TransAlta's unregulated subsidiary in the development of cogeneration facilities and the future of this area of business are discussed. 8 refs., 4 figs

Analysis of electrode microbial communities in an up-flow bioelectrochemical system treating azo dye wastewater

International Nuclear Information System (INIS)

Cui, Min-Hua; Cui, Dan; Gao, Lei; Cheng, Hao-Yi; Wang, Ai-Jie

2016-01-01

Bioelectrochemical system (BES) is a rapidly developing technology covering contamination remediation, resource recovery and power generation. Electrode biofilms play a key role in BES operation. In this work, a single chamber up-flow bioelectrochemical system (UBES) was assembled with two preinoculated anodes and two raw cathodes for azo dye wastewater treatment. Microbial community structures of these electrodes after long-term operation (more than 200 days) were carried out by high-throughput Illumina 16S rRNA gene MiSeq sequencing platform. Microorganisms belonging to Enterobacter, Desulfovibrio and Enterococcus, which are capable of bidirectional extracellular electron transfer, were found to be the dominant members in all biofilms. Neither the polarity nor the position of the electrodes obviously altered the microbial community structures. This study provides a feasible strategy to build electrode active biofilms in a BES for azo dye wastewater treatment and gives great inspirations to bring this technology closer to application.

Electrode configuration effects on the electrification and voltage variation in an electrostatic inkjet printing head

International Nuclear Information System (INIS)

Choi, Kyung Hyun; Ali, Adnan; Rahman, Ahsan; Malik Mohammad, Nauman; Rahman, Khalid; Khan, Arshad; Khan, Saleem; Kim, D S

2010-01-01

The electrode configuration of an electrostatic inkjet printing head is under study. This paper introduces the development of a new electrostatic inkjet head with an improved electrode configuration as compared to the conventional configuration. Two tungsten electrodes, connected in parallel, are inserted into the electrostatic print head at a certain angle from opposite sides. The aim of this double-side inserted angular electrodes (DSIAEs) head is to intensify the electrification of the fluid inside the head at minimum suitable exposure of the electrode, which results in maximizing surface charge density. The main advantage of the DSIAEs head is to get a very stable meniscus at low applied voltage for printing. This stable meniscus is transformed to a very stable jet by increasing the applied voltage. Therefore, printed patterns obtained with this DSIAEs head are more uniform because of a more stable meniscus and jet as compared to a conventional electrostatic vertically inserted single electrode head. Also, with this DSIAEs configuration, the life of the electrostatic inkjet printing head is increased.

Stable configurations of graphene on silicon

Energy Technology Data Exchange (ETDEWEB)

Javvaji, Brahmanandam; Shenoy, Bhamy Maithry [Department of Aerospace Engineering, Indian Institute of Science, Bangalore 560012 (India); Mahapatra, D. Roy, E-mail: droymahapatra@aero.iisc.ernet.in [Department of Aerospace Engineering, Indian Institute of Science, Bangalore 560012 (India); Ravikumar, Abhilash [Department of Metallurgical and Materials Engineering, National Institute of Technology Karnataka, Surathkal 575025 (India); Hegde, G.M. [Center for Nano Science and Engineering, Indian Institute of Science, Bangalore 560012 (India); Rizwan, M.R. [Department of Metallurgical and Materials Engineering, National Institute of Technology Karnataka, Surathkal 575025 (India)

2017-08-31

Highlights: • Simulations of epitaxial growth process for silicon–graphene system is performed. • Identified the most favourable orientation of graphene sheet on silicon substrate. • Atomic local strain due to the silicon–carbon bond formation is analyzed. - Abstract: Integration of graphene on silicon-based nanostructures is crucial in advancing graphene based nanoelectronic device technologies. The present paper provides a new insight on the combined effect of graphene structure and silicon (001) substrate on their two-dimensional anisotropic interface. Molecular dynamics simulations involving the sub-nanoscale interface reveal a most favourable set of temperature independent orientations of the monolayer graphene sheet with an angle of ∽15° between its armchair direction and [010] axis of the silicon substrate. While computing the favorable stable orientations, both the translation and the rotational vibrations of graphene are included. The possible interactions between the graphene atoms and the silicon atoms are identified from their coordination. Graphene sheet shows maximum bonding density with bond length 0.195 nm and minimum bond energy when interfaced with silicon substrate at 15° orientation. Local deformation analysis reveals probability distribution with maximum strain levels of 0.134, 0.047 and 0.029 for 900 K, 300 K and 100 K, respectively in silicon surface for 15° oriented graphene whereas the maximum probable strain in graphene is about 0.041 irrespective of temperature. Silicon–silicon dimer formation is changed due to silicon–carbon bonding. These results may help further in band structure engineering of silicon–graphene lattice.

Fundamentals of the LISA stable flight formation

International Nuclear Information System (INIS)

Dhurandhar, S V; Nayak, K Rajesh; Koshti, S; Vinet, J-Y

2005-01-01

The joint NASA-ESA mission, LISA, relies crucially on the stability of the three-spacecraft constellation. Each of the spacecraft is in heliocentric orbit forming a stable triangle. In this paper we explicitly show with the help of the Clohessy-Wiltshire equations that any configuration of spacecraft lying in the planes making angles of ±60 0 with the ecliptic and given suitable initial velocities within the plane, can be made stable in the sense that the inter-spacecraft distances remain constant to first order in the dimensions of the configuration compared with the distance to the Sun. Such analysis would be useful in order to carry out theoretical studies on the optical links, simulators, etc

Photo-induced refractive index and topographical surface gratings in functionalized nanocarbon solid film

Energy Technology Data Exchange (ETDEWEB)

McGee, David J.; Ferrie, John; Plachy, Aljoscha [Department of Physics, The College of New Jersey, Ewing, New Jersey 08628 (United States); Joo, Yongho; Choi, Jonathan; Kanimozhi, Catherine; Gopalan, Padma, E-mail: pgopalan@cae.wisc.edu [Department of Materials Science and Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706 (United States)

2015-11-02

We demonstrate that a single-walled carbon nanotube network noncovalently coupled with a pyrene-modified azo-benzene chromophore functions as a host matrix for a broad range of photo-orientation and photomechanical effects. The chromophore could be efficiently reoriented through repeated trans-cis-trans isomerization under linearly polarized 480 nm light, with Δn of 0.012 at 650 nm and fast characteristic rise-times of 0.12 s. Erasable phase diffraction gratings could also be written, with permanent surface relief gratings forming at sufficiently long irradiation times. In addition to demonstrating a mechanism for photo-manipulation of single-walled carbon nanotubes, these results show photo-orientation of chromophores in azo-functionalized single-walled carbon nanotube networks as a path towards the photosensitive tuning of the electrostatic environment of the nanotube.

Photo-induced refractive index and topographical surface gratings in functionalized nanocarbon solid film

International Nuclear Information System (INIS)

McGee, David J.; Ferrie, John; Plachy, Aljoscha; Joo, Yongho; Choi, Jonathan; Kanimozhi, Catherine; Gopalan, Padma

2015-01-01

We demonstrate that a single-walled carbon nanotube network noncovalently coupled with a pyrene-modified azo-benzene chromophore functions as a host matrix for a broad range of photo-orientation and photomechanical effects. The chromophore could be efficiently reoriented through repeated trans-cis-trans isomerization under linearly polarized 480 nm light, with Δn of 0.012 at 650 nm and fast characteristic rise-times of 0.12 s. Erasable phase diffraction gratings could also be written, with permanent surface relief gratings forming at sufficiently long irradiation times. In addition to demonstrating a mechanism for photo-manipulation of single-walled carbon nanotubes, these results show photo-orientation of chromophores in azo-functionalized single-walled carbon nanotube networks as a path towards the photosensitive tuning of the electrostatic environment of the nanotube

Isolation and Characterization of Paracoccus sp. GSM2 Capable of Degrading Textile Azo Dye Reactive Violet 5

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Mallikarjun C. Bheemaraddi

2014-01-01

Full Text Available A potential bacterial strain GSM2, capable of degrading an azo dye Reactive Violet 5 as a sole source of carbon, was isolated from textile mill effluent from Solapur, India. The 16S rDNA sequence and phenotypic characteristics indicated an isolated organism as Paracoccus sp. GSM2. This strain exhibited complete decolorization of Reactive Violet 5 (100 mg/L within 16 h, while maximally it could decolorize 800 mg/L of dye within 38 h with 73% decolorization under static condition. For color removal, the most suitable pH and temperature were pH 6.0–9.0 and 25–40°C, respectively. The isolate was able to decolorize more than 70% of five structurally different azo dyes within 38 h. The isolate is salt tolerant as it can bring out more than 90% decolorization up to a salt concentration of 2% (w/v. UV-Visible absorption spectra before and after decolorization suggested that decolorization was due to biodegradation and was further confirmed by FT-IR spectroscopy. Overall results indicate the effectiveness of the strain GSM2 explored for the treatment of textile industry effluents containing various azo dyes. To our knowledge, this could be the first report on biodegradation of Reactive Violet 5 by Paracoccus sp. GSM2.

'It was like I had to fit into a category': Care-seekers' experiences of gender regulation in the Swedish trans-specific healthcare.

Science.gov (United States)

Linander, Ida; Alm, Erika; Goicolea, Isabel; Harryson, Lisa

2017-05-01

The few previous studies investigating regulation of gender in trans-specific healthcare are mainly based on text material and interviews with care-providers or consist solely of theoretical analyses. There is a lack of studies analysing how the regulation of gender is expressed in the care-seeker's own experiences, especially in a Nordic context. The aim of this study is to analyse narratives of individuals with trans experiences (sometimes called transgender people) to examine how gender performances can be regulated in trans-specific care in Sweden. The conceptual framework is inspired by trans studies, a Foucauldian analysis of power, queer phenomenology and the concept of cisnormativity. Fourteen interviews with people with trans experiences are analysed with constructivist grounded theory. The participants' experiences indicate that gender is constructed as norm-conforming, binary and stable in trans-specific healthcare. This gendered position is resisted, negotiated and embraced by the care-seekers. Norms and discourses both inside and outside trans-specific care contribute to the regulation and limit the room for action for care-users. We conclude that a trans-specific care that has a confirming approach to its care-users, instead of the current focus on gender norm conformity, has the potential to increase the self-determination of gender performance and increase the quality of care.

Direct determination of absolute configuration: a vibrational circular dichroism study on dimethyl-substituted phenyloxiranes synthesized by Shi epoxidation

DEFF Research Database (Denmark)

Fristrup, Peter; Lassen, Peter Rygaard; Tanner, David Ackland

2008-01-01

obtained using DFT/B3LYP calculations, and the differences between experiment and theory are discussed. The absolute configuration at the benzylic position was established as being (R), (S) and (R) for the cis, trans and geminal dimethylsubstituted phenyloxiranes, respectively. In all three cases...

Three-vortex configurations in trapped Bose-Einstein condensates

International Nuclear Information System (INIS)

Seman, J. A.; Henn, E. A. L.; Shiozaki, R. F.; Ramos, E. R. F.; Caracanhas, M.; Castilho, P.; Castelo Branco, C.; Tavares, P. E. S.; Poveda-Cuevas, F. J.; Magalhaes, K. M. F.; Bagnato, V. S.; Haque, M.; Roati, G.

2010-01-01

We report on the creation of three-vortex clusters in a 87 Rb Bose-Einstein condensate by oscillatory excitation of the condensate. This procedure can create vortices of both circulations, so that we are able to create several types of vortex clusters using the same mechanism. The three-vortex configurations are dominated by two types, namely, an equilateral-triangle arrangement and a linear arrangement. We interpret these most stable configurations respectively as three vortices with the same circulation and as a vortex-antivortex-vortex cluster. The linear configurations are very likely experimental signatures of predicted stationary vortex clusters.

Stable hydrostatic equilibrium configurations of the galaxy and implications for its halo

International Nuclear Information System (INIS)

Bloemen, J.B.G.M.

1987-01-01

Using a variety of observations, it is shown that the gaseous, magnetic field, and cosmic-ray components in the local region of the Galaxy may be in a large-scale hydrostatic equilibrium that is stable against Parker-type instabilities. Lower limits for the density of the halo are derived as a function of its scale height. The temperature of the hot medium in the disk and at large distances from the plane is found to be typically about a million K in a stable equilibrium, whereas around z roughly 1-3 kpc the temperature could be only 200,000-300,000 K. The scale height of the sum of cosmic-ray and magnetic field pressures in a stable hydrostatic equilibrium state is found to be only weakly dependent on the scale height of the gaseous halo. 109 references

Facts about trans fats

Science.gov (United States)

Trans fat is a type of dietary fat . Of all the fats, trans fat is the worst for your health. Too much ... from solid margarine to soft margarine. Ask what type of fats foods are cooked in when you eat out ...

UV-visible-DAD and 1H-NMR spectroscopy data fusion for studying the photodegradation process of azo-dyes using MCR-ALS.

Science.gov (United States)

Fernández, Cristina; Pilar Callao, M; Larrechi, M Soledad

2013-12-15

The photodegradation process of three azo-dyes - Acid Orange 61, Acid Red 97 and Acid Brown 425 - was monitored simultaneously by ultraviolet-visible spectroscopy with diode array detector (UV-vis-DAD) and (1)H-nuclear magnetic resonance ((1)H-NMR). Multivariate curve resolution-alternating least squares (MCR-ALS) was applied to obtain the concentration and spectral profile of the chemical compounds involved in the process. The analysis of the H-NMR data suggests there are more intermediate compounds than those obtained with the UV-vis-DAD data. The fusion of UV-vis-DAD and the (1)H-NMR signal before the multivariate analysis provides better results than when only one of the two detector signals was used. It was concluded that three degradation products were present in the medium when the three azo-dyes had practically degraded. This study is the first application of UV-vis-DAD and (1)H-NMR spectroscopy data fusion in this field and illustrates its potential as a quick method for evaluating the evolution of the azo-dye photodegradation process. © 2013 Elsevier B.V. All rights reserved.

Exploración estocástica de las superficies de energía potencial de dímeros cis-trans y trans-trans del ácido fórmico

Directory of Open Access Journals (Sweden)

Said F. Figueredo

2014-01-01

Full Text Available Potential energy surface (PES of cis-trans and trans-trans formic acid dimers were sampled using a stochastic method, and the geometries, energies, and vibrational frequencies were computed at B3LYP/6-311++G(3df,2p level of theory. The results show that molar free energy of dimerization deviated up to 108.4% when basis set superposition error (BSSE and zero-point energy (ZPE were not considered. For cis-trans dimers, C=O and O - H bond weakened, whereas C - O bonds strengthened due to dimerization. Also, trans-trans FA dimers did not show a trend regarding strengthening or weakening of the C=O, O - H and C - O bonds.

Descoloração redutiva de corantes azo e o efeito de mediadores redox na presença do aceptor de elétrons sulfato Reductive decolourisation of azo dyes and the effect of redox mediators in the presence of the electron acceptor sulfate

Directory of Open Access Journals (Sweden)

Mayara Carantino Costa

2010-01-01

Full Text Available We investigated the impact of sulphate and the redox mediator Anthraquinone-2,6-disulfonate (AQDS on the decolorization of the azo dyes Congo Red (CR and Reactive Black 5 (RB5. In anaerobic reactors free of extra sulphate dosage, the color removal efficiency decreased drastically when the external electron donor ethanol was removed. In presence of an extra dosage of sulphate, CR decolourisations were 47.8% (free of AQDS and 96.5% (supplemented with AQDS. The decolourisations achieved in both reactors with RB5 were lower than the ones found with CR. Finally, the biogenic sulphide contribution on azo dye reduction was negligiable.

Decolorization of direct poly azo dye with nanophotocatalytic UV/NiO process

Directory of Open Access Journals (Sweden)

Ali Assadi

2012-01-01

Full Text Available Aims: The aim of the present study is to investigate the efficiency of ultraviolet/ nickel oxide (UV/NiO system as one form of advanced oxidation processes (AOP for decolorization of red poly azo. Materials and Methods: This study was conducted as a laboratory scale in a batch mode. Ultraviolet radiation was provided by a low pressure (11 W UV lamp. Effects of various factors including pH, different irradiation durations, different concentration of nickel oxide, and initial dye concentration were evaluated. Results: The results of the UV/NiO system′s assessment showed that UV light alone cannot remove DR 80 dye. Nickel oxide is an effective catalyst in the decolorization of dye with the nanophotocatalytic process. The decolorization efficiency increases with decreasing pH value and the optimum pH value is 4. Fainally, the highest removal efficiency achieved by UV/NiO process for DR 80 dye with concentrations of 25 mg/l and 50 mg/l was 94.3% and 82.2%, respectively. UV/NiO-based decolorization process follows pseudo-second-order reaction kinetics. Conclusions: From the findings of the present study, it can be concluded that UV/NiO process is an effective technique for decolorization of poly azo dye, DR 80, in aqueous solutions.

New complex product introduction by means of product configuration

DEFF Research Database (Denmark)

Bonev, Martin; Korell, Manuel; Hvam, Lars

-uct innovation can effectively been supported. Es-pecially for engineering companies moving to-wards Mass Customization, compared to mass pro-ducers the challenges caused by the complexity of their products and by the highly uncertain markets are much higher. This study develops and validates a framework which....... Traditional research has thereby either focused on defining modelling techniques for the configuration model of stable products, on improved configura-tion algorithms, or on the impact of configurators on companies’ operations. However, little attention has yet been paid how the growing need for prod...

Adsorption configurations of two nitrogen atoms on graphene

International Nuclear Information System (INIS)

Rani, Babita; Jindal, V. K.; Dharamvir, Keya

2014-01-01

We present calculations for different possible configurations of two nitrogen adatoms on graphene using the code VASP, based on Density Functional Theory (DFT). Two N atoms adsorbed on the graphene sheet can share a bond in two ways. They take positions either just above two adjacent carbon atoms or they form a bridge across opposite bonds of a hexagon in the graphene sheet. Both these configurations result into structural distortion of the sheet. Another stable configuration involving two N atoms consists of an N 2 molecule which is physisorbed at a distance 3.69 Å on the graphene sheet. Two N atoms can also be adsorbed on alternate bridge sites of neighbouring hexagons of graphene. This configuration again leads to distortion of the sheet in perpendicular direction

Adsorption of the reactive azo dyes onto NH4Cl-induced activated carbon

Directory of Open Access Journals (Sweden)

Sakine Shekoohiyan

2016-03-01

Full Text Available Background: The efficacy of NH4Cl-induced activated carbon (NAC was examined in order to adsorb RR198, an azo reactive model dye, from an aqueous solution. Methods: The effects of pH (3 to 10, adsorbent dose (0.1 to 1.2 g/L, dye concentration and contact time on the adsorption efficiency were investigated. Results: The results showed that the removal of dye was highest at a solution pH of 7 and a powder dose of 1.1 g/L. The 85.9%, 72.6% and 65.4% removal of RR198 was obtained for a concentration of 25, 50 and 100 mg/L, respectively, at a relatively short contact time of 30 minutes, and at optimum pH and NAC concentrations of 1 g/L. The experimental data for kinetic analysis illustrated a best fit to the pseudo-second-order model. The study data on equilibrium were modeled using Langmuir, Freundlich and Dubinin–Radushkevich models; the Langmuir equation provided the best fit for the data. Conclusion: Therefore, the NAC appears to be an efficient and appropriate adsorbent for the removal of reactive azo dyes from waste streams.

Square and bow-tie configurations in the cyclic evasion problem

Science.gov (United States)

Arnold, M. D.; Golich, M.; Grim, A.; Vargas, L.; Zharnitsky, V.

2017-05-01

Cyclic evasion of four agents on the plane is considered. There are two stationary shapes of configurations: square and degenerate bow-tie. The bow-tie is asymptotically attracting while the square is of focus-center type. Normal form analysis shows that square is nonlinearly unstable. The stable manifold consists of parallelograms that all converge to the square configuration. Based on these observations and numerical simulations, it is conjectured that any non-parallelogram non-degenerate configuration converges to the bow-tie.

Cis By Trans

OpenAIRE

Rodovalho,Amara Moira

2017-01-01

Cis, trans: above all, metaphors. Cisjordan, region skirting the Jordan River. Cisplatin, Uruguay’s ancient name, region occupying one of the banks of the Prata River. Trans- Amazonian, that which crosses the Amazon; transatlantic, that which crosses the Atlantic. Cisalpine, transalpine. The geometric isomerism of Organic Chemistry, where “cis” are atoms that, when molecules are divided in half, remain on the same side, and “trans” those remaining on opposite sides. Ev...

Treatment of a non-azo dye aqueous solution by CWAO in continuous reactor using a Ni catalyst derived from hydrotalcite-like precursor

International Nuclear Information System (INIS)

Vallet, Ana; Besson, Michèle; Ovejero, Gabriel; García, Juan

2012-01-01

Highlights: ► Ni supported over hydrotalcite calcined precursors as catalyst. ► Catalytic wet air oxidation in trickle bed reactor for Basic Yellow 11 removal. ► Dye removal depends on temperature, initial dye concentration and flow rate. ► The catalyst proved to be stable and efficient for the dye degradation. - Abstract: Catalytic wet air oxidation (CWAO) of a Basic Yellow 11 (BY11) aqueous solution, chosen as a model of a hardly biodegradable non-azo dye was carried out in a continuous-flow trickle-bed reactor, using nickel supported over hydrotalcite precursor calcined at 550 °C. An increase in the reaction temperature (120–180 °C), and a decrease in dye concentration (1000–3000 ppm) or liquid flow rate (0.1–0.7 mL min −1 ) enhanced the CWAO performance in a 30 and 19% for the variation of the temperature and concentration respectively. After a small leaching observed within the first hours, the catalyst proved to be very stable during the 65-day reaction. The CWAO process was found to be very efficient, achieving BY11 conversion up to 95% and TOC conversion up to 85% at 0.1 mL min −1 and 180 °C under 5 MPa air.

Crystallinity and the effect of ionizing radiation in polyethylene. V. Distribution of trans-vinylene and trans, trans conjugated double bonds in linear polyethylene

International Nuclear Information System (INIS)

Patel, G.N.

1975-01-01

Freeze-dried chain folded single crystals and the single crystals without amorphous surface layers (crystalline cores) of different thicknesses of linear polyethylene were irradiated with 60 Co γ-rays up to 600 Mrad. Concentration of trans-vinylene double bonds and conjugated diene produced during irradiation of the crystals was measured by infrared. Concentrations of trans-vinylene and of the conjugated diene were independent of thickness of crystalline core which suggest that the double bonds were randomly distributed in the crystalline parts of the crystals. Concentrations of trans-vinylene and of conjugated double bonds were lower in chain-folded crystals than in the crystalline cores and this suggests that the folds (amorphous surface layers) are less preferential sites for formation of the double bonds. The zero-order growth and first-order decay kinetics of trans-vinylene double bonds was studied by the equation derived by Dole et al. The equation is strictly obeyed up to 300 Mrad and the results then deviate. Since there is the decay of trans-vinylene double bonds and though there are no crosslinks in the crystalline cores, it has been suggested that the decay of the double bond does not result in the crosslinks

PUTAS Y TRANS. ¿ESTÁN LAS MUJERES TRANS EN LAS NARRATIVAS SOBRE LA PROSTITUCIÓN?

Directory of Open Access Journals (Sweden)

Liza García Reyes

2015-06-01

Full Text Available Este artículo evidencia los principales resultados de la investigación cualitativa titulada: Putas y trans. Narrativas sobre mujeres trans en España –desarrollada en 2010–, la cual estudió su presencia en textos académicos sobre prostitución en España, producidos entre los años 2000-2009. El análisis de contenido de 34 narrativas evidenció que las referencias a mujeres trans resulta escasa en ellas, aun siendo ellas quienes tienen mayor presencia en la prostitución, en proporción con las mujeres biológicas. Solo nueve textos mencionan la experiencia trans al interior de la prostitución y, entre estos, el asunto solo aparece asertivamente descrito cuando son las propias mujeres trans quienes escriben. AbstractThis paper shows the results of a qualitative research entitled: Hookers and Trans Women: Narratives about trans women in Spain. This study was developed in 2010 and it is based on presence of trans women in the academic texts of prostitution in Spain produced between 2000 and 2009. The content analysis of thirty four narratives showed that the references to in transsexual women in these texts were few, although they have more presence into prostitution, in relation to the biological women. Only nine texts show an experience of prostitution and among these, transexperience only is described assertively when transsexual women write the texts themselves.

Clinical research on high myopia treatments using AMARIS trans-epithelial PRK

Directory of Open Access Journals (Sweden)

Wu-Qiang Shan

2015-12-01

Full Text Available AIM:To evaluate the efficiency and safety of high myopia treatments using AMARIS trans-epithelial photorefractive keratectomy(PRK.METHODS:One hundred and thirty six eyes in 68 patients with high myopic were treated using Amaris trans-epithelial PRK during December 2012～December 2013. Post-operative pain, haze, visual acuity, refraction and intraocular pressure(IOPwere analyzed during 12mo follow-up post-operatively.RESULTS:One hundred and eight eyes in 54 patients felt no discomfort at all, while 28 eyes in 14 patients reported dry eye, slight pain and foreign body sensation. UCVA between the two groups showed statistically different at 3, 6mo and 1a(t=2.04, P=0.047. UCVA at 3mo was the best compared with those at other time pionts, and became stable at 6mo. UCVA of all patients were above 0.8 at 12mo,and had no difference with that before operations(t=1.508, P=0.1670. Haze were hardly seen, and most of them were between grade 0～1. The patients' satisfaction was over 85% according to the survey about night vision, dry eye and asthenopia.CONCLUSION:Because of the great advantages of no-touch, fast recovery and less side effects, trans-epithelial PRK has great efficiency, safety and satisfaction. It now is the most ideal method of surface ablation for high myopia treatments.

Cost of Oil and Biomass Supply Shocks under Different Biofuel Supply Chain Configurations

Energy Technology Data Exchange (ETDEWEB)

Uria Martinez, Rocio [ORNL; Leiby, Paul Newsome [ORNL; Brown, Maxwell L. [National Renewable Energy Laboratory (NREL)

2018-04-01

This analysis estimates the cost of selected oil and biomass supply shocks for producers and consumers in the light-duty vehicle fuel market under various supply chain configurations using a mathematical programing model, BioTrans. The supply chain configurations differ by whether they include selected flexibility levers: multi-feedstock biorefineries; advanced biomass logistics; and the ability to adjust ethanol content of low-ethanol fuel blends, from E10 to E15 or E05. The simulated scenarios explore market responses to supply shocks including substitution between gasoline and ethanol, substitution between different sources of ethanol supply, biorefinery capacity additions or idling, and price adjustments. Welfare effects for the various market participants represented in BioTrans are summarized into a net shock cost measure. As oil accounts for a larger fraction of fuel by volume, its supply shocks are costlier than biomass supply shocks. Corn availability and the high cost of adding biorefinery capacity limit increases in ethanol use during gasoline price spikes. During shocks that imply sudden decreases in the price of gasoline, the renewable fuel standard (RFS) biofuel blending mandate limits the extent to which flexibility can be exercised to reduce ethanol use. The selected flexibility levers are most useful in response to cellulosic biomass supply shocks.

An investigation on the effect of bleaching environment on pitting corrosion and trans-passive dissolution of 316 stainless steel

International Nuclear Information System (INIS)

Moayed, M.H.; Golestanipour, M.

2004-01-01

Pitting corrosion and trans-passive dissolution of 316 stainless steel in solution containing five percent of commercial bleaching liquid was investigated by employing potentiodynamic polarization method and recording corrosion potential during immersion. Today commercial bleaching liquids are widely used as cleaner additives, therefore, those house appliances made from stainless steels are in contact with aqueous solution containing bleaching liquid. This may cause sever localized corrosion and trans-passive dissolution. In order to investigate the possibility of trans-passive dissolution of stainless steel by bleaching liquid, potentiodynamic polarization and recording variation of corrosion potential of specimens were carried out in 0.2 M Na 2 SO 4 solution containing 5 %wt. commercial bleaching liquid. A 500 mV drop in trans-passive potential and also instantaneously ennobling corrosion potential revealed the possibility of trans-passive dissolution due to oxidizing effect of the species such as free chlorine and its derivatives in bleaching liquid. Evaluation of the occurrence of localized corrosion at the presence of Cl - and bleaching liquid was investigated by similar electrochemical experiments in 0.2 M Na 2 SO 4 + 0.4M NaCl containing 5%wt. bleaching solution. Initiation of stable pitting at potentials lower than trans-passive potential as well as sharp increasing of corrosion potential in this environment demonstrates the possibility of pitting corrosion. (authors)

Radical feminists & trans activists truce

OpenAIRE

Mackay, F.

2014-01-01

#GenderWeek: Truce! When radical feminists and trans feminists empathise\\ud Feminist Times\\ud By Finn Mackay \\ud read all #GenderWeek articles.\\ud We wanted to explore the ground between the polarised, entrenched positions in the so-called “TERF-war”. Radical feminists on one pole, trans-inclusionary feminists and trans activists on the other. The disputed territory being women-only space, language and the ever changing legal framework surrounding gender.\\ud Entrenchment leads to stalemate. S...

The contribution of fermentative bacteria and methanogenic archaea to azo dye reduction by a thermophilic anaerobic consortium

NARCIS (Netherlands)

Santos, dos A.B.; Cervantes, F.J.; Madrid, de M.P.; Bok, de F.A.M.; Stams, A.J.M.; Lier, van J.B.

2006-01-01

The contribution of fermentative bacteria and methanogenic archaea to azo dye reduction by a thermophilic anaerobic consortium was studied. Additionally, the effects of different electron-donating substrates and the redox mediator riboflavin on dye reduction were assessed by using either a

Azo dye removal in a membrane-free up-flow biocatalyzed electrolysis reactor coupled with an aerobic bio-contact oxidation reactor

International Nuclear Information System (INIS)

Cui, Dan; Guo, Yu-Qi; Cheng, Hao-Yi; Liang, Bin; Kong, Fan-Ying; Lee, Hyung-Sool; Wang, Ai-Jie

2012-01-01

Highlights: ► A membrane-free up-flow biocatalyzed electrolysis reactor coupled with an aerobic bio-contact oxidation reactor was developed. ► Alizarin Yellow R as the mode of azo dyes was efficiently converted to p-phenylenediamine (PPD) and 5-aminosalicylic acid (5-ASA). ► PPD and 5-ASA were further oxidized in a bio-contact oxidation reactor. ► The mechanism of UBER for azo dye removal was discussed. - Abstract: Azo dyes that consist of a large quantity of dye wastewater are toxic and persistent to biodegradation, while they should be removed before being discharged to water body. In this study, Alizarin Yellow R (AYR) as a model azo dye was decolorized in a combined bio-system of membrane-free, continuous up-flow bio-catalyzed electrolysis reactor (UBER) and subsequent aerobic bio-contact oxidation reactor (ABOR). With the supply of external power source 0.5 V in the UBER, AYR decolorization efficiency increased up to 94.8 ± 1.5%. Products formation efficiencies of p-phenylenediamine (PPD) and 5-aminosalicylic acid (5-ASA) were above 90% and 60%, respectively. Electron recovery efficiency based on AYR removal in cathode zone was nearly 100% at HRTs longer than 6 h. Relatively high concentration of AYR accumulated at higher AYR loading rates (>780 g m −3 d −1 ) likely inhibited acetate oxidation of anode-respiring bacteria on the anode, which decreased current density in the UBER; optimal AYR loading rate for the UBER was 680 g m −3 d −1 (HRT 2.5 h). The subsequent ABOR further improved effluent quality. Overall the Chroma decreased from 320 times to 80 times in the combined bio-system to meet the textile wastewater discharge standard II in China.

Azo dye removal in a membrane-free up-flow biocatalyzed electrolysis reactor coupled with an aerobic bio-contact oxidation reactor

Energy Technology Data Exchange (ETDEWEB)

Cui, Dan; Guo, Yu-Qi; Cheng, Hao-Yi; Liang, Bin; Kong, Fan-Ying [State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, No. 202 Haihe Road, Harbin 150090 (China); Lee, Hyung-Sool [Department of Civil and Environmental Engineering, University of Waterloo, 200 University Avenue West Waterloo, Ontario, Canada N2L 3G1 (Canada); Wang, Ai-Jie, E-mail: waj0578@hit.edu.cn [State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, No. 202 Haihe Road, Harbin 150090 (China)

2012-11-15

Highlights: Black-Right-Pointing-Pointer A membrane-free up-flow biocatalyzed electrolysis reactor coupled with an aerobic bio-contact oxidation reactor was developed. Black-Right-Pointing-Pointer Alizarin Yellow R as the mode of azo dyes was efficiently converted to p-phenylenediamine (PPD) and 5-aminosalicylic acid (5-ASA). Black-Right-Pointing-Pointer PPD and 5-ASA were further oxidized in a bio-contact oxidation reactor. Black-Right-Pointing-Pointer The mechanism of UBER for azo dye removal was discussed. - Abstract: Azo dyes that consist of a large quantity of dye wastewater are toxic and persistent to biodegradation, while they should be removed before being discharged to water body. In this study, Alizarin Yellow R (AYR) as a model azo dye was decolorized in a combined bio-system of membrane-free, continuous up-flow bio-catalyzed electrolysis reactor (UBER) and subsequent aerobic bio-contact oxidation reactor (ABOR). With the supply of external power source 0.5 V in the UBER, AYR decolorization efficiency increased up to 94.8 {+-} 1.5%. Products formation efficiencies of p-phenylenediamine (PPD) and 5-aminosalicylic acid (5-ASA) were above 90% and 60%, respectively. Electron recovery efficiency based on AYR removal in cathode zone was nearly 100% at HRTs longer than 6 h. Relatively high concentration of AYR accumulated at higher AYR loading rates (>780 g m{sup -3} d{sup -1}) likely inhibited acetate oxidation of anode-respiring bacteria on the anode, which decreased current density in the UBER; optimal AYR loading rate for the UBER was 680 g m{sup -3} d{sup -1} (HRT 2.5 h). The subsequent ABOR further improved effluent quality. Overall the Chroma decreased from 320 times to 80 times in the combined bio-system to meet the textile wastewater discharge standard II in China.

Trans advanced surface laser ablation (TransPRK) outcomes using SmartPulseTechnology.

Science.gov (United States)

Aslanides, Ioannis M; Kymionis, George D

2017-02-01

To evaluate early visual rehabilitation, post-operative pain, epithelial healing and haze after transepithelial photorefractive keratectomy (TransPRK) using the SmartPulseTechnology (SPT) of Schwind Amaris (Schwind eye-tech-solutions GmbH, Kleinostheim, Germany). This was a retrospective comparative evaluation of a cohort of myopic patients undergoing TransPRK with SPT (group 1), with one matched control group that underwent conventional TransPRK (group 2). All cases had a 6-month post-operative follow-up including visual acuity and slit-lamp examination. Subjective evaluation of pain was recorded post-operatively. 49 eyes of 25 patients in group 1 and 40 eyes of 20 patients in group 2 were enrolled. The patients' visual rehabilitation was significantly faster in group 1, one day and one week post-operatively (P0.05). TransPRK using SPT provides promising results in the early post-operative period. Visual rehabilitation, re-epithelialization and pain were faster in the early post-operative period in group 1 in comparison with group 2. Haze formation was not significantly different between the two groups; however, it was consistently less in group 1. Copyright © 2016 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.

Trans as Contested Intelligibility

DEFF Research Database (Denmark)

Raun, Tobias

2014-01-01

Denne artikel rejser en række epistemologiske og metodologiske spørgsmål vedrørende læsningen af trans som identitetskategori. Disse spørgsmål er stærkt underbelyste i en skandinavisk akademisk kontekst, om end der el- lers i stigende grad produceres analyser af trans identitetsnarrativer. Artikl...

Synthesis and Evaluation of Changes Induced by Solvent and Substituent in Electronic Absorption Spectra of New Azo Disperse Dyes Containig Barbiturate Ring

Directory of Open Access Journals (Sweden)

Hooshang Hamidian

2013-01-01

Full Text Available Six azo disperse dyes were prepared by diazotizing 4-amino hippuric acid and coupled with barbituric acid and 2-thiobarbituric acid. Then, the products were reacted with aromatic aldehyde, sodium acetate, and acetic anhydride, and oxazolone derivatives were formed. Characterization of the dyes was carried out by using UV-Vis, FT-IR, 1H NMR and 13C NMR, and mass spectroscopic techniques. The solvatochromic behavior of azo disperse dyes was evaluated in various solvents. The effects of substituents of aromatic aldehyde, barbiturate, and thiobarbiturate ring on the color of dyes were investigated.

Degradation of azo dyes by sequential Fenton's oxidation and aerobic biological treatment

International Nuclear Information System (INIS)

Tantak, Nilesh P.; Chaudhari, Sanjeev

2006-01-01

A two stage sequential Fenton's oxidation followed by aerobic biological treatment train was used to achieve decolorization and to enhance mineralization of azo dyes, viz. Reactive Black 5 (RB5), Reactive Blue 13 (RB13), and Acid Orange 7 (AO7). In the first stage, Fenton's oxidation process was used while in the second stage aerobic sequential batch reactors (SBRs) were used as biological process. Study was done to evaluate effect of pH on Fenton's oxidation process. Results reveal that pH 3 was optimum pH for achieving decolorization and dearomatization of dyes by Fenton's process. Degradation of dye was assessed by COD reduction and reduction in aromatic amines (naphthalene chromophores) which was measured by reduction in absorbance at 200 nm. More than 95% of color was removed with Fenton's oxidation process in all dyes. In overall treatment train 81.95, 85.57, and 77.83% of COD reduction was achieved in RB5, RB13, and AO7 dyes, respectively. In the Fenton's oxidation process 56, 24.5, and 80% reduction in naphthalene group was observed in RB5, RB13, and AO7, respectively, which further increased to 81.34, 68.73, and 92% after aerobic treatment. Fenton's oxidation process followed by aerobic SBRs treatment sequence seems to be viable method for achieving significant degradation of azo dye

Treatment of a non-azo dye aqueous solution by CWAO in continuous reactor using a Ni catalyst derived from hydrotalcite-like precursor.

Science.gov (United States)

Vallet, Ana; Besson, Michèle; Ovejero, Gabriel; García, Juan

2012-08-15

Catalytic wet air oxidation (CWAO) of a Basic Yellow 11 (BY11) aqueous solution, chosen as a model of a hardly biodegradable non-azo dye was carried out in a continuous-flow trickle-bed reactor, using nickel supported over hydrotalcite precursor calcined at 550°C. An increase in the reaction temperature (120-180°C), and a decrease in dye concentration (1000-3000 ppm) or liquid flow rate (0.1-0.7 mL min(-1)) enhanced the CWAO performance in a 30 and 19% for the variation of the temperature and concentration respectively. After a small leaching observed within the first hours, the catalyst proved to be very stable during the 65-day reaction. The CWAO process was found to be very efficient, achieving BY11 conversion up to 95% and TOC conversion up to 85% at 0.1 mL min(-1) and 180°C under 5 MPa air. Copyright © 2012 Elsevier B.V. All rights reserved.

Synthesized TiO{sub 2}/ZSM-5 composites used for the photocatalytic degradation of azo dye: Intermediates, reaction pathway, mechanism and bio-toxicity

Energy Technology Data Exchange (ETDEWEB)

Zhou, Kefu; Hu, Xin-Yan [College of the Environment and Ecology, Xiamen University, Xiamen (China); Chen, Bor-Yann; Hsueh, Chung-Chuan [Department of Chemical and Materials Engineering, National I-Lan University, I-Lan, Taiwan (China); Zhang, Qian [Department of Environmental Engineering, National Taiwan University, Taipei, Taiwan (China); Wang, Jiajie; Lin, Yu-Jung [College of the Environment and Ecology, Xiamen University, Xiamen (China); Chang, Chang-Tang, E-mail: ctchang73222@gmail.com [Department of Environmental Engineering, National I-Lan University, I-Lan, Taiwan (China)

2016-10-15

Highlights: • The major photo-catalytic degradation pathway of azo-dye was elaborated according to the identification of by-products from GC–MS and IC analysis. • Comparative assessment on characteristics of abiotic and biotic dye decolorization was analyzed. • EDTA (hole scavengers) and t-BuOH (radical scavengers) were used to determine the main active oxidative species in the system. • The toxicity effects of degradation intermediates of Reactive Black 5 (RB5) on the cellular respiratory activity were assessed. - Abstract: In this study, a one-step solid dispersion method was used to synthesize titanium dioxide (TiO{sub 2})/Zeolite Socony Mobil-5 (ZSM-5) composites with substantially reduced time and energy consumption. A degradation efficiency of more than 95% was achieved within 10 min using 50% PTZ (synthesized TiO{sub 2}/ZSM-5 composites with TiO{sub 2} contents of 50 wt% loaded on ZSM-5) at pH 7 and 25 °C. The possible degradation pathway of azo-dye Reactive Black 5 (RB5) was investigated using gas chromatography–mass spectrometry and ion chromatography (IC). The bonds between the N atoms and naphthalene groups are likely attacked first and cleaved by hydroxyl radicals, ultimately resulting in the decolorization and mineralization of the azo dye. A comparative assessment of the characteristics of abiotic and biotic dye decolorization was completed. In addition, the toxicity effects of the degradation intermediates of azo-dye RB5 on cellular respiratory activity were analyzed. The bio-toxicity results showed that the decay rate constants of CO{sub 2} production from the azo-dye RB5 samples at different degradation times increased initially and subsequently decreased, indicating that intermediates of higher toxicity could adhere to the catalyst surface and gradually destroyed by further photocatalytic oxidation. Additionally, EDTA (hole scavengers) and t-BuOH (radical scavengers) were used to detect the main active oxidative species in the system

Statistical theory of dislocation configurations in a random array of point obstacles

International Nuclear Information System (INIS)

Labusch, R.

1977-01-01

The stable configurations of a dislocation in an infinite random array of point obstacles are analyzed using the mathematical methods of statistical mechanics. The theory provides exact distribution functions of the forces on pinning points and of the link lengths between points on the line. The expected number of stable configurations is a function of the applied stress. This number drops to zero at the critical stress. Due to a degeneracy problem in the line count, the value of the flow stress cannot be determined rigorously, but we can give a good approximation that is very close to the empirical value

The Danish trans-fatty acids ban

DEFF Research Database (Denmark)

Vallgårda, Signild

2017-01-01

In 2003 an executive order was issued banning industrially produced trans-fatty acids above a low level in food items in Denmark. To date, only a few other countries have followed Denmark’s example. The way health consequences of trans fats were translated by the different actors enabled the crea......In 2003 an executive order was issued banning industrially produced trans-fatty acids above a low level in food items in Denmark. To date, only a few other countries have followed Denmark’s example. The way health consequences of trans fats were translated by the different actors enabled...

Biodecolorization of the azo dye Reactive Red 2 by a halotolerant enrichment culture.

Science.gov (United States)

Beydilli, M Inan; Pavlostathis, Spyros G

2007-11-01

The decolorization of the azo dye Reactive Red 2 (RR2) under anoxic conditions was investigated using a mesophilic (35 degrees C) halotolerant enrichment culture capable of growth at 100 g/L sodium chloride (NaCl). Batch decolorization assays were conducted with the unacclimated halotolerant culture, and dye decolorization kinetics were determined as a function of the initial dye, biomass, carbon source, and an externally added oxidation-reduction mediator (anthraquinone-2,6-disulphonic acid) concentrations. The maximum biomass-normalized RR2 decolorization rate by the halotolerant enrichment culture under batch, anoxic incubation conditions was 26.8 mg dye/mg VSSxd. Although RR2 decolorization was inhibited at RR2 concentrations equal to and higher than 300 mg/L, the halotolerant culture achieved a 156-fold higher RR2 decolorization rate compared with a previously reported, biomass-normalized RR2 decolorization rate by a mixed mesophilic (35 degrees C) methanogenic culture in the absence of NaCl. Decolorization kinetics at inhibitory RR2 levels were described based on the Haldane model (Haldane, 1965). Five repetitive dyeing/decolorization cycles performed using the halotolerant culture and the same RR2 dyebath solution demonstrated the feasibility of biological renovation and reuse of commercial-strength spent reactive azo dyebaths.

Impacto dos mediadores redox na remoção de cor de corantes azo e antraquinônico por lodo granular anaeróbio sob condições mesofílicas e termofílicas Impact of redox mediators on colour removal of azo and anthraquinone dyes by anaerobic granular sludge under mesophilic and thermophilic conditions

Directory of Open Access Journals (Sweden)

André Bezerra dos Santos

2007-03-01

Full Text Available Investigou-se o efeito de diferentes mediadores redox (MR na remoção de cor de corantes azo e antraquinônico pelo uso de lodo granular anaeróbio sob condições mesofílicas (30ºC e termofílicas (55ºC. Comprovou-se em experimento em batelada que a adição de concentrações catalíticas de MR pode ter um efeito marcante nas taxas de descoloração do corante azo Reactive Red 2 (RR2, mas o mesmo comportamento não pode ser obtido com o corante antraquinônico Reactive Blue 5 (RB5. Entretanto, com ambos os corantes, o simples aumento da temperatura de incubação para condições termofílicas fez acelerar consideravelmente os processos de descoloração, comparados com condições mesofílicas. Por exemplo, a constante de primeira ordem "k" da redução dos corantes RR2 e RB5, foi aumentada em 6,2 e 11 vezes, respectivamente, à 55ºC quando comparado com 30ºC. Por fim, comprovou-se em experimentos de fluxo contínuo, a boa performance do tratamento termofílico na descoloração redutiva de corantes azo.The effect of different redox mediators (RM on colour removal of azo and anthraquinone dyes was investigated with anaerobic granular sludge under mesophilic (30ºC and thermophilic (55ºC conditions. Batch experiments revealed that an addition of catalytic concentrations of RM provided a remarkable effect on the decolourisation rates of the azo dye Reactive Red 2 (RR2, but the same effect could not be obtained with the anthraquinone dye Reactive Blue 5 (RB5. Nevertheless, for both dyes, the temperature increase to thermophilic conditions was an effective strategy to considerably accelerate the decolourisation process compared to mesophilic conditions. For instance, the first-order rate constant "k" of RR2 and RB5 reduction, was increased in 6.2 and 11-fold, respectively, at 55ºC in comparison with 30ºC. Such an effect of the temperature on the reductive decolourisation of azo dye was also verified in continuous flow experiments.

TransForm: TransAlta 2000 annual report

International Nuclear Information System (INIS)

2001-01-01

Financial information from TransAlta Corp. was presented along with a review of their operations throughout 2000 and a summary of the how the electric utility is doing in terms of power generation, independent power producers, transmission and energy marketing. The utility has changed from a regulated vertically integrated utility into one of Canada's largest non-regulated electric power generators. The utility sold its retail businesses in Alberta and New Zealand and now focuses on coal and hydro generation, gas generation, high-voltage transmission and energy marketing. The newly constructed Centralia, Washington generation facility was brought on line with 1,340 MW in May 2000, on time and on budget. This was the platform to diversify their generation into the United States. The utility reported a solid financial year with $177.9 million in earnings from continuing operations, an 83 per cent increase from 1999, driven mostly by the results of Centralia and power marketing and trading businesses. A financial loss was suffered when the Wabamum power plant in Alberta was shut down for several months to repair a boiler. The utility made excellent progress toward their goal of 15,000 megawatts by 2005 by starting with the construction of what will be one of Canada's largest cogeneration facilities at Sarnia, Ontario. TransAlta also commissioned a 360 MW cogeneration facility at Poplar Creek at Suncor's Fort McMurray oil sand facility. TransAlta also has an excellent track record in developing power generation projects internationally. refs., tabs., figs

TransCanada PipeLines Limited 1998 annual report : TransCanada energy solutions

International Nuclear Information System (INIS)

1999-01-01

Financial information from TransCanada PipeLines Limited and a review of the company's 1998 operations was made available for the benefit of shareholders. TransCanada's pipeline system transports natural gas and crude oil from Western Canada Sedimentary Basin to North America's major energy markets. Net earnings from continuing operations for 1998, before unusual charges, were $575 million ($ 355 million after unusual charges) compared to $522 million for 1997. Solid performances from the energy transmission and international business, when compared to 1997, were more than offset by a decreased contribution from energy processing. TransCanada recorded integration costs of $166 million, after tax, related to the merger with NOVA in 1998, which was the major operational accomplishment during the year, creating a seamless economic energy delivery, processing and marketing system from the wellhead to the market. tabs., figs

Comparative evaluation of capillary electrophoresis and high-performance liquid chromatography for the separation of cis-cis, cis-trans, and trans-trans isomers of atracurium besylate.

Science.gov (United States)

de Moraes, M de L; Polakiewicz, B; Mattua, M F; Tavares, M F

1998-01-01

Atracurium besylate is a highly selective nondepolarizing neuromuscular blocking agent routinely used during anesthetic procedures. The commercial presentation of this drug is a mixture of positional isomers, cis-cis, cis-trans, and trans-trans. Reversed-phase high-performance liquid chromatography has been the technique of choice for the analysis of atracurium besylate formulations at the quality control laboratory of Núcleo de Desenvolvimento Cristália (São Paulo, Brazil), a local pharmaceutical company. HPLC analysis is usually conducted under gradient elution using acetonitrile/0.1 M phosphate buffer eluent mixture as mobile phase and an octadecyl silica (ODS)-packed column. The complete elution of the three isomers takes about 1 hr. In this work, an alternative capillary electrophoresis methodology was developed. The complete resolution of all three isomers was accomplished in about 13 min (+20 kV/72 cm, 211 nm direct detection) using a 60-mM phosphate buffer solution (pH 4) containing 20 mM beta-cyclodextrin and 4 M urea. The isomer ratio was found to be 59.1% cis-cis, 35.9% cis-trans, and 5.02% trans-trans (expected ratio: 59:35:6). Laudanosine, a major metabolite of atracurium besylate, was identified in two commercially available formulations, Tracur (Núcleo de Desenvolvimento Cristália) and Tracrium (Glaxo Wellcome, S.A., Rio de Janeiro, Brazil). Its concentration increases considerably during storage of the product, even if the product is stored at low temperatures.

Effect of the nature of p-substituents in benzene ring of azo compounds based on chromotropic acid on their reactivity

Energy Technology Data Exchange (ETDEWEB)

Savvin, S B; Dedkova, V P; Azarashvili, M A; Likhonina, E A

1988-08-01

Effect of acceptor and donor substituents in a reagent on degree of contrast and selectivity of spectrophotometric beryllium determination as well as other elements was considered taking derivatives of orthanilic-azo-chromotropic acid as an example. The optimal pH region of aminoorthanilic-azo-chromotropic acid interaction with Be 5-6.5; the optimal wavelength is 640 nm. The solution colour changes from violet-red to blue during complex formation. Selectivity increases after addition of masking substances. Be determination on the background of 4-fold Cu and VO/sup 2+/ amounts 8-fold Al amounts, 2-fold Zn amounts is possible in the presence of 5-fold EDTA amounts unsubstituted reagent is characterized by the lowest degree of contrast and selectivity of reactions with metals.

The role of climatic cycles and trans-Saharan migration corridors in species diversification: Biogeography of Psammophis schokari group in North Africa.

Science.gov (United States)

Gonçalves, Duarte Vasconcelos; Martínez-Freiría, Fernando; Crochet, Pierre-André; Geniez, Philippe; Carranza, Salvador; Brito, José Carlos

2018-01-01

Highlands, hydrographic systems and coastal areas have been hypothesised to form corridors across the hyperarid Sahara desert in North Africa, allowing dispersal and gene flow for non-xeric species. Here we aim to provide a genetic test for the trans-Saharan corridor model, and predict the location and stability of ecological-corridors, by combining phylogeography and palaeoclimatic modelling. The model was the Psammophis schokari (Schokari sand racer) group, fast-moving and widely distributed generalist colubrids occurring mostly in arid and semiarid scrublands. We combined dated phylogenies of mitochondrial and nuclear markers with palaeoclimatic modelling. For the phylogeographic analysis, we used 75 samples of P. schokari and P. aegyptius, and Bayesian and Maximum-Likelihood methods. For the ecological models, we used Maxent over the distribution of P. schokari and West African lineages. Models were projected to past conditions (mid Holocene, Last Glacial Maximum and Last Inter-Glacial) to infer climatic stable areas. Climatic stability was predicted to be mostly restricted to coastal areas and not spatially continuous. A putative temporary trans-Saharan corridor was identified in Eastern Sahara, with a more stable one along the Atlantic coast. Six parapatric lineages were identified within P. schokari, four occurring in North Africa. These likely diverged during the Pliocene. The Tamanraset River might have been a vicariant agent. African lineages may have experienced further subsequent diversification during the late Pleistocene. The main P. schokari refugia were probably located along the northern margins of the Sahara, allowing its North-to-South colonization. Trans-Saharan corridors seem to have played a role in P. schokari biogeography, allowing colonization of central Saharan mountains and Sahel. Some might have worked as refugia, and even the most stable corridors may have sections working as filters, depending on each climatic phase. We expect the use

Trans Ova Genetics, L.C.

Science.gov (United States)

The EPA is providing notice of a proposed Administrative Penalty Assessment against Trans Ova Genetics, L.C., a business located at 2938 380th Street Sioux Center, IA 51250, for alleged violations at the Trans Ova Genetics, L.C.’s facility located in 12425

Optimization of extraction of high purity all-trans-lycopene from tomato pulp waste.

Science.gov (United States)

Poojary, Mahesha M; Passamonti, Paolo

2015-12-01

The aim of this work was to optimize the extraction of pure all-trans-lycopene from the pulp fractions of tomato processing waste. A full factorial design (FFD) consisting of four independent variables including extraction temperature (30-50 °C), time (1-60 min), percentage of acetone in n-hexane (25-75%, v/v) and solvent volume (10-30 ml) was used to investigate the effects of process variables on the extraction. The absolute amount of lycopene present in the pulp waste was found to be 0.038 mg/g. The optimal conditions for extraction were as follows: extraction temperature 20 °C, time 40 min, a solvent composition of 25% acetone in n-hexane (v/v) and solvent volume 40 ml. Under these conditions, the maximal recovery of lycopene was 94.7%. The HPLC-DAD analysis demonstrated that, lycopene was obtained in the all-trans-configuration at a very high purity grade of 98.3% while the amount of cis-isomers and other carotenoids were limited. Copyright © 2015 Elsevier Ltd. All rights reserved.

Antiferroelectric phase in liquid crystalline compounds with azo group in their molecular core

Czech Academy of Sciences Publication Activity Database

Kašpar, Miroslav; Novotná, Vladimíra; Hamplová, Věra; Podoliak, Natalia; Nonnenmacher, D.; Giesselmann, F.; Glogarová, Milada

2011-01-01

Roč. 38, č. 3 (2011), s. 309-315 ISSN 0267-8292 R&D Projects: GA AV ČR IAA100100911; GA AV ČR(CZ) GA202/09/0047 Grant - others:German Czech bilateral program(DE) D4-CZ5/2010-2011; GA UK(CZ) SVV-2011-263303 Institutional research plan: CEZ:AV0Z10100520 Keywords : liquid crystals * antiferroelectricity * azo linkage group * photosensitivity Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.858, year: 2011

Density functional theory study of structural and electronic properties of trans and cis structures of thiothixene as a nano-drug.

Science.gov (United States)

Noori Tahneh, Akram; Bagheri Novir, Samaneh; Balali, Ebrahim

2017-11-25

The geometrical structure, electronic and optical properties, electronic absorption spectra, vibrational frequencies, natural charge distribution, MEP analysis and thermodynamic properties of the trans and cis structures of the drug thiothixene were investigated using density functional theory (DFT) and time-dependent DFT (TDDFT) methods with the B3LYP hybrid functional and 6-311 + G(d,p) basis set. The results of the calculations demonstrate that the cis structure of thiothixene has appropriate quantum properties that can act as an active medicine. The relative energies of trans and cis structures of thiothixene shows that the cis structure is more stable than the trans structure, with a small energy difference. TDDFT calculations show that the cis structure of thiothixene has the best absorption properties. The calculated NLO properties show that the NLO properties of the cis structure of thiothixene are higher than the trans structure, and the fact that the chemical hardness of the cis structure is lower than that of the trans structure that indicates that the reactivity and charge transfer of the cis isomer of thiothixene is higher than that of trans thiothixene. The molecular electrostatic potential (MEP) maps of both structures of thiothixene demonstrate that the oxygen atoms of the molecule are appropriate areas for electrophilic reactions. The vibrational frequencies of the two conformations of thiothixene demonstrate that both structures of thiothixene have almost similar modes of vibrations. The calculated thermodynamic parameters show that these quantities increase with enhancing temperature due to the enhancement of molecular vibrational intensities with temperature. Graphical abstract Trans/Cis isomerization of thiothixene drug.

Consumo de ácidos grasos trans y riesgo cardiovascular Consumption of trans fatty acids and cardiovascular risk

Directory of Open Access Journals (Sweden)

Fernando Manzur J

2009-06-01

Full Text Available Los ácidos grasos con configuración trans poco se encuentran en los alimentos de manera natural, sino que se incorporan a éstos como consecuencia de modificaciones principalmente debidas a los procesos industriales de hidrogenación a que se someten los aceites para convertirlos en grasas sólidas. Aún cuando su estructura incluye dobles enlaces, el tipo de configuración permite un comportamiento biológico similar al de los ácidos grasos saturados, con efectos negativos sobre múltiples funciones celulares. La evidencia demuestra que son perjudiciales para la salud, en especial a lo que se refiere a riesgo de enfermedad cardiovascular, razón por la cual es importante disminuir su consumo. Teniendo en consideración la evidencia obtenida de investigaciones sobre las alteraciones del metabolismo producidas por los ácidos grasos trans, es posible plantear una precaución lógica hacia el consumo de dietas ricas en dichos ácidos. Sus efectos deletéreos serían incluso peores en aquellas poblaciones que consumen bajas cantidades de ácidos grasos esenciales. De ahí surge la importancia de iniciar con prontitud políticas sanitarias orientadas a controlar la aterosclerosis en nuestro país. Las mismas deben estar necesariamente sustentadas sobre un conocimiento profundo de las características o condiciones particulares a las que nuestra población se encuentra sometida. Sólo así podrá darse inicio a una intervención efectiva sobre nuestros cuestionados hábitos alimentarios.Trans fatty acids are scarcely found naturally in food; they are incorporated to it as a result of modifications mainly due to hydrogenation industrial processes to which oils are submitted in order to obtain solid fats. Even when its structure includes double bonds, the type of configuration allows a biological behavior similar to that of saturated fatty acids, with negative effects on multiple cellular functions. The evidence shows that they are harmful to health

Radiolysis of organic triphenylmethane, anthraquinone, xanthene, oxazine, thiazine and azo dyes in polymeric films

International Nuclear Information System (INIS)

Khabarov, V.N.; Kozlov, L.L.; Molin, A.A.; Mekhanic, T.V.

1988-01-01

Effect of air oxygen and temperature (77 - 323 K) on decolorization radiation-chemical processes of triphenylmethane, anthraquinone, xanthene, oxazine, thiazine and azo dyes in different polymeric matrices is investigated. Radiation decolorization rate for the majority of dyes increases at the irradiation in O 2 presence, which is, presumably, connected with the dye oxidation by the singlet oxygen. The organic dyes manifest the most radiation resistance in polyethyleneterephthalate and polystyrene films

Properties of transparent and conductive Al:ZnO/Au/Al:ZnO multilayers on flexible PET substrates

International Nuclear Information System (INIS)

Dimopoulos, T.; Bauch, M.; Wibowo, R.A.; Bansal, N.; Hamid, R.; Auer, M.; Jäger, M.; List-Kratochvil, E.J.W.

2015-01-01

Highlights: • Transparent, low resistive AZO/Au/AZO layers were sputtered on PET substrates. • AZO/Au/AZO has higher figure of merit than ITO for specific Au thicknesses. • The resistance of AZO/Au/AZO is stable against repetitive substrate bending. • AZO/Au/AZO electrode performance is comparable to ITO in light emitting diodes. - Abstract: We investigate the structural, electrical and optical properties of transparent electrodes, consisting of Al-doped ZnO (AZO) and ultrathin Au layers, sputtered on polyethylene terephthalate (PET). These electrodes are relevant for optoelectronic devices and thin film photovoltaics. When deposited on AZO, Au films as thin as 3 nm form electrically conductive, meandering structures, whereas uniform Au films are obtained from a thickness of 5 nm. The sheet resistance decreases with Au thickness, reaching 7 Ω for 11 nm-thick Au. AZO/Au/AZO trilayers combine lowest resistance with highest transparency, while their resistance stability against bending fatigue is superior to the Sn-doped In 2 O 3 (ITO) electrode. The figure of merit of AZO/Au/AZO is larger than of ITO for Au thickness equal to or larger than 9 nm. To demonstrate the applicability of the AZO/Au/AZO transparent electrode, simple organic light emitting diodes were fabricated and tested in comparison to PET/ITO standard substrates

Properties of transparent and conductive Al:ZnO/Au/Al:ZnO multilayers on flexible PET substrates

Energy Technology Data Exchange (ETDEWEB)

Dimopoulos, T., E-mail: theodoros.dimopoulos@ait.ac.at [AIT-Austrian Institute of Technology, Energy Department, Photovoltaic Systems, Giefinggasse 2, 1210, Vienna (Austria); Bauch, M.; Wibowo, R.A.; Bansal, N. [AIT-Austrian Institute of Technology, Energy Department, Photovoltaic Systems, Giefinggasse 2, 1210, Vienna (Austria); Hamid, R. [AIT-Austrian Institute of Technology, Mobility Department, Electric Drive Technologies, Giefinggasse 2, 1210, Vienna (Austria); Auer, M.; Jäger, M. [NanoTecCenter Weiz Forschungsgesellschaft mbH, Franz-Pichler Straße 32, A-8160 Weiz (Austria); List-Kratochvil, E.J.W. [NanoTecCenter Weiz Forschungsgesellschaft mbH, Franz-Pichler Straße 32, A-8160 Weiz (Austria); Institute of Solid State Physics, Graz University of Technology, Petersgasse 16, A-8010 Graz (Austria)

2015-10-15

Highlights: • Transparent, low resistive AZO/Au/AZO layers were sputtered on PET substrates. • AZO/Au/AZO has higher figure of merit than ITO for specific Au thicknesses. • The resistance of AZO/Au/AZO is stable against repetitive substrate bending. • AZO/Au/AZO electrode performance is comparable to ITO in light emitting diodes. - Abstract: We investigate the structural, electrical and optical properties of transparent electrodes, consisting of Al-doped ZnO (AZO) and ultrathin Au layers, sputtered on polyethylene terephthalate (PET). These electrodes are relevant for optoelectronic devices and thin film photovoltaics. When deposited on AZO, Au films as thin as 3 nm form electrically conductive, meandering structures, whereas uniform Au films are obtained from a thickness of 5 nm. The sheet resistance decreases with Au thickness, reaching 7 Ω for 11 nm-thick Au. AZO/Au/AZO trilayers combine lowest resistance with highest transparency, while their resistance stability against bending fatigue is superior to the Sn-doped In{sub 2}O{sub 3} (ITO) electrode. The figure of merit of AZO/Au/AZO is larger than of ITO for Au thickness equal to or larger than 9 nm. To demonstrate the applicability of the AZO/Au/AZO transparent electrode, simple organic light emitting diodes were fabricated and tested in comparison to PET/ITO standard substrates.

Spectroscopic and density functional theory studies of trans-3-(trans-4-imidazolyl)acrylic acid.

Science.gov (United States)

Arjunan, V; Remya, P; Sathish, U; Rani, T; Mohan, S

2014-08-14

The structural parameters, thermodynamic properties and vibrational frequencies of the optimised geometry of trans-3-(trans-4-imidazolyl)acrylic acid have been determined from B3LYP methods with 6-311++G(**) and cc-pVTZ basis sets. The effects of substituents (acrylyl group) on the imidazole vibrational frequencies are analysed. The vibrational frequencies of the fundamental modes of trans-3-(trans-4-imidazolyl)acrylic acid have been precisely assigned and analysed and the theoretical results are compared with the experimental vibrations. (1)H and (13)C NMR isotropic chemical shifts are calculated and the assignments made are compared with the experimental values. The energies of important MO's of the compound are also determined from DFT method. The total electron density and electrostatic potential of the compound are determined by natural bond orbital analysis. Various reactivity and selectivity descriptors such as chemical hardness, chemical potential, softness, electrophilicity, nucleophilicity and the appropriate local quantities employing natural population analysis (NPA) are calculated. Copyright © 2014 Elsevier B.V. All rights reserved.

Efficient degradation of Azo dyes by a newly isolated fungus Trichoderma tomentosum under non-sterile conditions.

Science.gov (United States)

He, Xiao-Ling; Song, Chao; Li, Yuan-Yuan; Wang, Ning; Xu, Lei; Han, Xin; Wei, Dong-Sheng

2018-04-15

A fast-growing fungus with remarkable ability to degrade several azo dyes under non-sterile conditions was isolated and identified. This fungus was identified as Trichoderma tomentosum. Textile effluent of ten-fold dilution could be decolorized by 94.9% within 72h before optimization. Acid Red 3R model wastewater with a concentration of 85.5mgL -1 could be decolorized by 99.2% within the same time after optimization. High-level of manganese peroxidase and low-level of lignin peroxidase activities were detected during the process of decolorization from the culture supernatant, indicating the possible involvement of two enzymes in azo dye decolorization. No aromatic amine products were detected from the degradation products of Acid Red 3R by gas chromatography-mass spectrometry (GC/MS) analysis, indicating the possible involvement of a special symmetrical oxidative degradation pathway. Phytotoxicity assay confirmed the lower toxicity toward the test plant seeds of the degradation products when compared to the original dye. Copyright © 2017 Elsevier Inc. All rights reserved.

Efficient azo dye decolorization in a continuous stirred tank reactor (CSTR) with built-in bioelectrochemical system.

Science.gov (United States)

Cui, Min-Hua; Cui, Dan; Gao, Lei; Cheng, Hao-Yi; Wang, Ai-Jie

2016-10-01

A continuous stirred tank reactor with built-in bioelectrochemical system (CSTR-BES) was developed for azo dye Alizarin Yellow R (AYR) containing wastewater treatment. The decolorization efficiency (DE) of the CSTR-BES was 97.04±0.06% for 7h with sludge concentration of 3000mg/L and initial AYR concentration of 100mg/L, which was superior to that of the sole CSTR mode (open circuit: 54.87±4.34%) and the sole BES mode (without sludge addition: 91.37±0.44%). The effects of sludge concentration and sodium acetate (NaAc) concentration on azo dye decolorization were investigated. The highest DE of CSTR-BES for 4h was 87.66±2.93% with sludge concentration of 12,000mg/L, NaAc concentration of 2000mg/L and initial AYR concentration of 100mg/L. The results in this study indicated that CSTR-BES could be a practical strategy for upgrading conventional anaerobic facilities against refractory wastewater treatment. Copyright © 2016 Elsevier Ltd. All rights reserved.

Treatment of a non-azo dye aqueous solution by CWAO in continuous reactor using a Ni catalyst derived from hydrotalcite-like precursor

Energy Technology Data Exchange (ETDEWEB)

Vallet, Ana, E-mail: avallet@quim.ucm.es [Grupo de Catalisis y Procesos de Separacion (CyPS), Departamento de Ingenieria Quimica, Facultad de Ciencias Quimicas, Universidad Complutense de Madrid, Avda. Complutense s/n, 28040 Madrid (Spain); Besson, Michele, E-mail: michele.besson@ircelyon.univ-lyon1.fr [IRCELYON, Institut de recherches sur la catalyse et l' environnement de Lyon, UMR5256 CNRS-Universite Lyon1, 2 Avenue Albert Einstein, F-69626 Villeurbanne Cedex (France); Ovejero, Gabriel; Garcia, Juan [Grupo de Catalisis y Procesos de Separacion (CyPS), Departamento de Ingenieria Quimica, Facultad de Ciencias Quimicas, Universidad Complutense de Madrid, Avda. Complutense s/n, 28040 Madrid (Spain)

2012-08-15

Highlights: Black-Right-Pointing-Pointer Ni supported over hydrotalcite calcined precursors as catalyst. Black-Right-Pointing-Pointer Catalytic wet air oxidation in trickle bed reactor for Basic Yellow 11 removal. Black-Right-Pointing-Pointer Dye removal depends on temperature, initial dye concentration and flow rate. Black-Right-Pointing-Pointer The catalyst proved to be stable and efficient for the dye degradation. - Abstract: Catalytic wet air oxidation (CWAO) of a Basic Yellow 11 (BY11) aqueous solution, chosen as a model of a hardly biodegradable non-azo dye was carried out in a continuous-flow trickle-bed reactor, using nickel supported over hydrotalcite precursor calcined at 550 Degree-Sign C. An increase in the reaction temperature (120-180 Degree-Sign C), and a decrease in dye concentration (1000-3000 ppm) or liquid flow rate (0.1-0.7 mL min{sup -1}) enhanced the CWAO performance in a 30 and 19% for the variation of the temperature and concentration respectively. After a small leaching observed within the first hours, the catalyst proved to be very stable during the 65-day reaction. The CWAO process was found to be very efficient, achieving BY11 conversion up to 95% and TOC conversion up to 85% at 0.1 mL min{sup -1} and 180 Degree-Sign C under 5 MPa air.

Synthesis of trans-disubstituted alkenes by cobalt-catalyzed reductive coupling of terminal alkynes with activated alkenes.

Science.gov (United States)

Mannathan, Subramaniyan; Cheng, Chien-Hong

2012-09-10

A cobalt-catalyzed reductive coupling of terminal alkynes, RC≡CH, with activated alkenes, R'CH=CH(2), in the presence of zinc and water to give functionalized trans-disubstituted alkenes, RCH=CHCH(2)CH(2)R', is described. A variety of aromatic terminal alkynes underwent reductive coupling with activated alkenes including enones, acrylates, acrylonitrile, and vinyl sulfones in the presence of a CoCl(2)/P(OMe)(3)/Zn catalyst system to afford 1,2-trans-disubstituted alkenes with high regio- and stereoselectivity. Similarly, aliphatic terminal alkynes also efficiently participated in the coupling reaction with acrylates, enones, and vinyl sulfone, in the presence of the CoCl(2)/P(OPh)(3)/Zn system providing a mixture of 1,2-trans- and 1,1-disubstituted functionalized terminal alkene products in high yields. The scope of the reaction was also extended by the coupling of 1,3-enynes and acetylene gas with alkenes. Furthermore, a phosphine-free cobalt-catalyzed reductive coupling of terminal alkynes with enones, affording 1,2-trans-disubstituted alkenes as the major products in a high regioisomeric ratio, is demonstrated. In the reactions, less expensive and air-stable cobalt complexes, a mild reducing agent (Zn) and a simple hydrogen source (water) were used. A possible reaction mechanism involving a cobaltacyclopentene as the key intermediate is proposed. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Photomechanical Deformation of Azobenzene-Functionalized Polyimides Synthesized with Bulky Substituents (Postprint)

Science.gov (United States)

2017-12-06

comparative UV − vis result (Figure S6, Supporting Information) that azoCBODA-BPADA has the lowest absorbance change for its azobenzene trans−cis...or trans−cis−trans reorientation processes upon irradiation of 365 nm UV or blue-green light (440−530 nm), respectively. Exposure of these materials...to UV light induces a trans−cis isomerization, resulting in a length reduction of the molecular axis of azobenzene from 9 Å (trans) to 5.5 Å (cis).10

Nonlinear optical parameters of nanocrystalline AZO thin film measured at different substrate temperatures

Energy Technology Data Exchange (ETDEWEB)

Jilani, Asim, E-mail: asim.jilane@gmail.com [Centre of Nanotechnology, King Abdulaziz University, Jeddah (Saudi Arabia); Abdel-wahab, M.Sh [Centre of Nanotechnology, King Abdulaziz University, Jeddah (Saudi Arabia); Materials Science and Nanotechnology Department, Faculty of Postgraduate Studies for Advanced Sciences, Beni -Suef University, Beni-Suef (Egypt); Al-ghamdi, Attieh A. [Centre of Nanotechnology, King Abdulaziz University, Jeddah (Saudi Arabia); Dahlan, Ammar sadik [Department of architecture, faculty of environmental design, King Abdulaziz University, Jeddah (Saudi Arabia); Yahia, I.S. [Department of Physics, Faculty of Science, King Khalid University, P.O. Box 9004, Abha (Saudi Arabia); Nano-Science & Semiconductor Labs, Department of Physics, Faculty of Education, Ain Shams University, Roxy, 11757 Cairo (Egypt)

2016-01-15

The 2.2 wt% of aluminum (Al)-doped zinc oxide (AZO) transparent and preferential c-axis oriented thin films were prepared by using radio frequency (DC/RF) magnetron sputtering at different substrate temperature ranging from room temperature to 200 °C. For structural analysis, X-ray Diffraction (XRD) and Atomic Force Electron Microscope (AFM) was used for morphological studies. The optical parameters such as, optical energy gap, refractive index, extinction coefficient, dielectric loss, tangent loss, first and third order nonlinear optical properties of transparent films were investigated. High transmittance above 90% and highly homogeneous surface were observed in all samples. The substrate temperature plays an important role to get the best transparent conductive oxide thin films. The substrate temperature at 150 °C showed the growth of highly transparent AZO thin film. Energy gap increased with the increased in substrate temperature of Al doped thin films. Dielectric constant and loss were found to be photon energy dependent with substrate temperature. The change in substrate temperature of Al doped thin films also affect the non-liner optical properties of thin films. The value of χ{sup (3)} was found to be changed with the grain size of the thin films that directly affected by the substrate temperature of the pure and Al doped ZnO thin films.

Epoxidation of the methamphetamine pyrolysis product, trans-phenylpropene, to trans-phenylpropylene oxide by CYP enzymes and stereoselective glutathione adduct formation

International Nuclear Information System (INIS)

Sanga, Madhu; Younis, Islam R.; Tirumalai, Padma S.; Bland, Tina M.; Banaszewska, Monica; Konat, Gregory W.; Tracy, Timothy S.; Gannett, Peter M.; Callery, Patrick S.

2006-01-01

Pyrolytic products of smoked methamphetamine hydrochloride are well established. Among the various degradation products formed, trans-phenylpropene (trans-β-methylstyrene) is structurally similar to styrene analogues known to be bioactivated by CYP enzymes. In human liver microsomes, trans-phenylpropene was converted to the epoxide trans-phenylpropylene oxide (trans-2-methyl-3-phenyloxirane) and cinnamyl alcohol. Incubation of trans-phenylpropene with microsomes in the presence of enzyme-specific P450 enzyme inhibitors indicated the involvement of CYP2E1, CYP1A2, and CYP3A4 enzymes. Both (R,R)-phenylpropylene oxide and (S,S)-phenylpropylene oxide were formed in human liver microsomal preparations. Enantiomers of trans-phenylpropylene oxide were stereoselectively and regioselectively conjugated in a Phase II drug metabolism reaction catalyzed by human liver cytosolic enzymes consisting of conjugation with glutathione. The structure of the phenylpropylene oxide-glutathione adduct is consistent with nucleophilic ring-opening by attack at the benzylic carbon. Exposure of cultured C6 glial cells to (S,S)-phenylpropylene oxide produced a cytotoxic response in a concentration-dependent manner based on cell degeneration and death

Decolorization of azo dyes Orange G using hydrodynamic cavitation coupled with heterogeneous Fenton process.

Science.gov (United States)

Cai, Meiqiang; Su, Jie; Zhu, Yizu; Wei, Xiaoqing; Jin, Micong; Zhang, Haojie; Dong, Chunying; Wei, Zongsu

2016-01-01

The present work demonstrates the application of the combination of hydrodynamic cavitation (HC) and the heterogeneous Fenton process (HF, Fe(0)/H2O2) for the decolorization of azo dye Orange G (OG). The effects of main affecting operation conditions such as the inlet fluid pressure, initial concentration of OG, H2O2 and zero valent iron (ZVI), the fixed position of ZVI, and medium pH on decolorization efficiency were discussed with guidelines for selection of optimum parameters. The results revealed that the acidic conditions are preferred for OG decolorizaiton. The decolorization rate increased with increasing H2O2 and ZVI concentration and decreased with increasing OG initial concentration. Besides, the decolorization rate was strongly dependent on the fixed position of ZVI. The analysis results of degradation products using liquid chromatography-ESI-TOF mass spectrometry revealed that the degradation mechanism of OG proceeds mainly via reductive cleavage of the azo linkage due to the attack of hydroxyl radical. The present work has conclusively established that the combination of HC and HF can be more energy efficient and gives higher decolorization rate of OG as compared with HC and HF alone. Copyright © 2015 Elsevier B.V. All rights reserved.

Ultrasound enhanced activation of peroxydisulfate by activated carbon fiber for decolorization of azo dye.

Science.gov (United States)

Huang, Tianyin; Zhang, Ke; Qian, Yajie; Fang, Cong; Chen, Jiabin

2018-02-20

Activated carbon fiber (ACF) has become an emerging activator for peroxydisulfate (PDS) to generate sulfate radical (SO 4 •- ). However, the relative low activation efficiency and poor contaminant mineralization limited its widespread application. Herein, ultrasound (US) was introduced to the ACF activated PDS system, and the synergistic effect of US and ACF in PDS activation and the enhancement of contaminant mineralization were investigated. The synergistic effect of US and ACF was observed in the PDS activation to decolorize orange G (OG). The decolorization efficiency increased with increasing ACF loading and US power, and PDS/OG ratio from 1 to 40. The activation energy was determined to be 24.065 kJ/mol. The radical-induced decolorization of OG took place on the surface of ACF, and both SO 4 •- and hydroxyl radical ( • OH) contributed to OG decolorization. The azo bond and naphthalene ring on OG were destructed to other aromatic intermediates and finally mineralized to CO 2 and H 2 O. The introduction of US in the ACF/PDS system significantly enhanced the mineralization of OG. The combination of US and PDS was highly efficient to activate PDS to decolorize azo dyes. Moreover, the introduction of US remarkably improved the contaminant mineralization.

A comparison of trans-cranial and trans-sphenoidal approaches for vision improvement due to pitutary adenomas

Directory of Open Access Journals (Sweden)

Fakhr Tabatabai SA

1997-07-01

Full Text Available To improve visual disturbance, optic nerve decompression can be performed via transcranial or tran-sphenoidal approaches. Although the surgical exposure in transcranial approach is favourable, yet the optic nerve's presence in the field may make it vulnerable to damage. Of fighty patients with different types of pituitary adenomas, 35 cases with medium-sized (1-3 cm tumors have been studied in a randomized clinical trial during a three year period, to compare the applicability of these approaches. While short hospital stay with better visual outcome was observed in fifteen trans-sphenoidal cases, in comparison to 20 trans-cranial cases, however the preoperative visual status and underlying disorders were similar in both groups. Decompressing the optic apparatus, trans-sphenoidally, seems beneficial, where there are no contraindications for the procedure in medium-sized pituitary adenomas

Flux loss during the equilibrium phase of field-reversed configurations

International Nuclear Information System (INIS)

Tuszewski, M.; Armstrong, W.T.; Bartsch, R.R.; Chrien, R.E.; Cochrane, J.C. Jr.; Kewish, R.W. Jr.; Klingner, P.; Linford, R.K.; McKenna, K.F.; Rej, D.J.; Sherwood, E.G.; Siemon, R.E.

1982-01-01

Field-reversed configurations are consistently formed at low filling pressures in the FRX-C device, with decay time of the trapped flux after formation much larger than the stable period. This contrasts with previous experimental observations

Flux loss during the equilibrium phase of field-reversed configurations

Energy Technology Data Exchange (ETDEWEB)

Tuszewski, M.; Armstrong, W.T.; Bartsch, R.R.; Chrien, R.E.; Cochrane, J.C. Jr.; Kewish, R.W. Jr.; Klingner, P.; Linford, R.K.; McKenna, K.F.; Rej, D.J.; Sherwood, E.G.; Siemon, R.E.

1982-10-01

Field-reversed configurations are consistently formed at low filling pressures in the FRX-C device, with decay time of the trapped flux after formation much larger than the stable period. This contrasts with previous experimental observations.

Reasons for decision in the matter of Trans Mountain Pipeline Inc. (formerly Terasen Pipelines (Trans Mountain) Inc.) : tariffs

International Nuclear Information System (INIS)

2007-01-01

In 2006 and 2007 Terasen Pipelines (Trans Mountain) Inc. (now Trans Mountain Pipeline Inc.) submitted a series of applications to the National Energy Board for revisions to the Trans Mountain Tariffs. They were filed in response to apportionment concerns on the Trans Mountain pipeline. Four of the applications involved pronounced and contentious changes to the capacity allocation procedures on the pipeline system. For ease of reference, the Board amalgamated its 4 decisions on these applications into a single document. A map of the Trans Mountain pipeline system as a whole was presented along with a detailed map indicating the delivery locations served by the system in the lower mainland of British Columbia and the state of Washington. The issues considered by the Board in each of these decisions included capacity allocation for Westridge Dock; capacity allocations to export destinations; common carriage requirements; and the need for creating a new barge subcategory. Relevant sections of the National Energy Board Act referred to in the decisions were highlighted. This document also listed the Trans Mountain Tariffs that have introduced notable revisions to the capacity allocation procedures on the system since September 2003. 16 refs., 2 figs., 3 appendices

Effect of addition of heavy metal ion on decolouration and degradation of azo dye in aqueous solution by gamma irradiation combined with ozone

International Nuclear Information System (INIS)

Lee, M.J.; Jin, J.H.; Nho, Y.C.; Arai, H.

1998-01-01

In decomposition of azo dyes solution by simultaneous application of gamma-ray and ozone treatment, the effect of addition of heavy metal ion upon decolouration and decomposition was studied. Cupric ion was used as a heavy metal ion. For the aqueous solution with and without addition of cupric ion, the degree of decolouration of 552 nm, the changes of pH, the reduction of TOC and BOD were measured as function of dose under condition of fixed concentration of ozone. It appeared that the addition of cupric ion played a positive role in decomposition of azo dye solution, but played a negative role in decolouration

Axisymmetric MHD stable sloshing ion distributions

International Nuclear Information System (INIS)

Berk, H.L.; Dominguez, N.; Roslyakov, G.V.

1986-07-01

The MHD stability of a sloshing ion distribution is investigated in a symmetric mirror cell. Fokker-Planck calculations show that stable configurations are possible for ion injection energies that are at least 150 times greater than the electron temperture. Special axial magnetic field profiles are suggested to optimize the favorable MHD properties

Micro-Sugar-Snap and -Wire-Cut Cookie Baking with Trans- and Zero-Trans-Fat Shortenings

Science.gov (United States)

The effect of trans- and zero-trans-fat shortenings on cookie-baking performance was evaluated, using the two AACC micro-cookie-baking methods. Regardless of fat type, sugar-snap cookies made with a given flour were larger in diameter, smaller in height, and greater in weight loss during baking tha...

Is HO3 minimum cis or trans? An analytic full-dimensional ab initio isomerization path.

Science.gov (United States)

Varandas, A J C

2011-05-28

The minimum energy path for isomerization of HO(3) has been explored in detail using accurate high-level ab initio methods and techniques for extrapolation to the complete basis set limit. In agreement with other reports, the best estimates from both valence-only and all-electron single-reference methods here utilized predict the minimum of the cis-HO(3) isomer to be deeper than the trans-HO(3) one. They also show that the energy varies by less than 1 kcal mol(-1) or so over the full isomerization path. A similar result is found from valence-only multireference configuration interaction calculations with the size-extensive Davidson correction and a correlation consistent triple-zeta basis, which predict the energy difference between the two isomers to be of only Δ = -0.1 kcal mol(-1). However, single-point multireference calculations carried out at the optimum triple-zeta geometry with basis sets of the correlation consistent family but cardinal numbers up to X = 6 lead upon a dual-level extrapolation to the complete basis set limit of Δ = (0.12 ± 0.05) kcal mol(-1). In turn, extrapolations with the all-electron single-reference coupled-cluster method including the perturbative triples correction yield values of Δ = -0.19 and -0.03 kcal mol(-1) when done from triple-quadruple and quadruple-quintuple zeta pairs with two basis sets of increasing quality, namely cc-cpVXZ and aug-cc-pVXZ. Yet, if added a value of 0.25 kcal mol(-1) that accounts for the effect of triple and perturbative quadruple excitations with the VTZ basis set, one obtains a coupled cluster estimate of Δ = (0.14 ± 0.08) kcal mol(-1). It is then shown for the first time from systematic ab initio calculations that the trans-HO(3) isomer is more stable than the cis one, in agreement with the available experimental evidence. Inclusion of the best reported zero-point energy difference (0.382 kcal mol(-1)) from multireference configuration interaction calculations enhances further the relative

Calculations of the excitation energies of all-trans and 11,12s-dicis retinals using localized molecular orbitals obtained by the elongation method

Science.gov (United States)

Kurihara, Youji; Aoki, Yuriko; Imamura, Akira

1997-09-01

In the present article, the excitation energies of the all-trans and the 11,12s-dicis retinals were calculated by using the elongation method. The geometries of these molecules were optimized with the 4-31G basis set by using the GAUSSIAN 92 program. The wave functions for the calculation of the excitation energies were obtained with CNDO/S approximation by the elongation method, which enables us to analyze electronic structures of aperiodic polymers in terms of the exciton-type local excitation and the charge transfer-type excitation. The excitation energies were calculated by using the single excitation configuration interaction (SECI) on the basis of localized molecular orbitals (LMOs). The LMOs were obtained in the process of the elongation method. The configuration interaction (CI) matrices were diagonalized by Davidson's method. The calculated results were in good agreement with the experimental data for absorption spectra. In order to consider the isomerization path from 11,12s-dicis to all-trans retinals, the barriers to the rotations about C11-C12 double and C12-C13 single bonds were evaluated.

Understanding the complexity of trans fatty acid reduction in the American diet: American Heart Association Trans Fat Conference 2006: report of the Trans Fat Conference Planning Group.

Science.gov (United States)

Eckel, Robert H; Borra, Susan; Lichtenstein, Alice H; Yin-Piazza, Shirley Y

2007-04-24

A 2-day forum was convened to discuss the current status and future implications of reducing trans fatty acids without increasing saturated fats in the food supply while maintaining functionality and consumer acceptance of packaged, processed, and prepared foods. Attendees represented the agriculture and oilseed industry and oil processing, food manufacturing, food service, government, food technology, and health and nutrition disciplines. Presentations included food science behind fatty acid technology, the health science of dietary fatty acids, alternatives to trans fatty acids, and the use of alternatives in food manufacturing and food service. The reduction of trans fatty acids in the food supply is a complex issue involving interdependent and interrelated stakeholders. Actions to reduce trans fatty acids need to carefully consider both intended and unintended consequences related to nutrition and public health. The unintended consequence of greatest concern is that fats and oils high in saturated fats, instead of the healthier unsaturated fats, might be used to replace fats and oils with trans fatty acids. Many different options of alternative oils and fats to replace trans fatty acids are available or in development. Decisions on the use of these alternatives need to consider availability, health effects, research and development investments, reformulated food quality and taste, supply-chain management, operational modifications, consumer acceptance, and cost. The conference demonstrated the value of collaboration between the food industry and health and nutrition professionals, and this conference model should be used to address other food development, processing, and/or technology issues.

Becoming lesbian: Monique Wittig's queer-trans-feminism.

Science.gov (United States)

Henderson, Kevin

2018-04-03

Inspired by Lynne Huffer's queer feminist genealogy, this article explores queer-trans-feminism as a project that would bring together queer, feminist, and transgender theory and politics into a shared critical lineage. I suggest that Monique Wittig is a neglected thinker who could re-enliven connections and debates within queer, feminist, and trans theory and politics. Utilizing recent historiographies of queer and feminist theory, I imagine what it would mean to hold on to the figure of the lesbian as a figure for queer-trans-feminist politics rather than render the lesbian anachronistic. I then explore the implications of Wittig's notion that "lesbians are not women" for a queer-trans-feminism. I argue that Wittig's critique of the language of the social sciences offers queer-trans-feminist scholars a source for contemporary self-critique and coalition.

Trans-Kullo jagatakse tükkideks / Kadrin Karner

Index Scriptorium Estoniae

Karner, Kadrin

2008-01-01

Primos OÜ omanik ja Trans-Kullo osanik Endel Siff ütles, et Trans-Kullo on aktsionäride erinevate ärihuvide tõttu läinud jagunemisele, mis võib lõppeda ettevõtte likvideerimisega. Lisa: Trans-Kullo

Sexual desire in trans persons: associations with sex reassignment treatment.

Science.gov (United States)

Wierckx, Katrien; Elaut, Els; Van Hoorde, Birgit; Heylens, Gunter; De Cuypere, Griet; Monstrey, Stan; Weyers, Steven; Hoebeke, Piet; T'Sjoen, Guy

2014-01-01

Sex steroids and genital surgery are known to affect sexual desire, but little research has focused on the effects of cross-sex hormone therapy and sex reassignment surgery on sexual desire in trans persons. This study aims to explore associations between sex reassignment therapy (SRT) and sexual desire in a large cohort of trans persons. A cross-sectional single specialized center study including 214 trans women (male-to-female trans persons) and 138 trans men (female-to-male trans persons). Questionnaires assessing demographics, medical history, frequency of sexual desire, hypoactive sexual desire disorder (HSDD), and treatment satisfaction. In retrospect, 62.4% of trans women reported a decrease in sexual desire after SRT. Seventy-three percent of trans women never or rarely experienced spontaneous and responsive sexual desire. A third reported associated personal or relational distress resulting in a prevalence of HSDD of 22%. Respondents who had undergone vaginoplasty experienced more spontaneous sexual desire compared with those who planned this surgery but had not yet undergone it (P = 0.03). In retrospect, the majority of trans men (71.0%) reported an increase in sexual desire after SRT. Thirty percent of trans men never or rarely felt sexual desire; 39.7% from time to time, and 30.6% often or always. Five percent of trans men met the criteria for HSDD. Trans men who were less satisfied with the phalloplasty had a higher prevalence of HSDD (P = 0.02). Trans persons who were more satisfied with the hormonal therapy had a lower prevalence of HSDD (P = 0.02). HSDD was more prevalent in trans women compared with trans men. The majority of trans women reported a decrease in sexual desire after SRT, whereas the opposite was observed in trans men. Our results show a significant sexual impact of surgical interventions and both hormonal and surgical treatment satisfaction on the sexual desire in trans persons. © 2013 International Society for Sexual

Properties of ballooning modes in the Heliotron configurations

International Nuclear Information System (INIS)

Nakajima, N.; Hudson, S.R.; Hegna, C.C.

2005-01-01

The stability of ballooning modes is influenced by the local and global magnetic shear and local and global magnetic curvature so significantly that it is fairly difficult to get those general properties in the three dimensional configurations with strong flexibility due to the external coil system. In the case of the planar axis heliotron configurations allowing a large Shafranov shift, like LHD, properties of the high-mode-number ballooning modes have been intensively investigated. It has been analytically shown that the local magnetic shear comes to disappear in the stellarator-like global magnetic shear region, as the Shafranov shift becomes large. Based on this mechanism and the characteristics of the local and global magnetic curvature, it is numerically shown that the destabilized ballooning modes have strong three-dimensional properties (both poloidal and toroidal mode couplings) in the Mercier stable region, and that those are fairly similar to ballooning modes in the axisymmetric system in the Mercier unstable region. As is well known, however, no quantization condition is applicable to the ballooning modes in the three-dimensional system without symmetry, and so the results of the high-mode-number ballooning modes in the covering space had to be confirmed in the real space. Such a confirmation has been done in the Mercier stable region and also in the Mercier unstable region by using three dimensional linearized ideal MHD stability code cas3d. Confirming the relation between high-mode-number ballooning analyses by the global mode analyses, the method of the equilibrium profile variations has been developed in the tree dimensional system, giving dt/dψ - dP/dψ stability diagram corresponding to the s - α diagram in tokamaks. This method of profile variation are very powerful to investigate the second stability of high-mode-number ballooning modes and has been more developed. Recently it has been applied to the plasma in the inward-shifted LHD

Chromatographic methods for determination of metals as chelate compounds with heterocyclic azo reagents

International Nuclear Information System (INIS)

Basova, E.M.; Bol'shova, T.A.; Shpigun, O.A.; Ivanov, V.M.

1993-01-01

Methods for separation and concentration of transition metals as well as cadmium in form of chelates with heterocyclic azo compounds namely, PAN(1-(2-pyridylaso)-2-naphthol), PAR(4-(2-pyridylazo)-resorcin), Br-PAAP (2-(5-bromine-2-pyridylazo)-5-diethyl aminophenol) are considered. The Br-PAAP reagent is the most sensitive and widely-applied one in extraction and highly-efficient liquid chromatography. Methods of sorption concentration with subsequent element determination directly on the sorbent without microelements separation or destruction are the most promissing ones

Styrene and Azo-Styrene Based Colorimetric Sensors for Highly Selective Detection of Cyanide

OpenAIRE

Prestiani, Agustina Eka; Purwono, Bambang

2017-01-01

A novel styrene (1) and azo-styrene (2) based chemosensor from vanillin has been successfully synthesized. Sensor 1 was obtained by one step Knoevenagel condensation of Ultrasound method and sensor 2 by coupling diazo and Knoevenagel condensation reaction. Both of sensors showed high sensitivity and selectivity to detect CN- in aqueous media, even the presence of other anions, such as F-, Cl-, Br-, I-, CO32-, SO42-, H2PO4-, and AcO-. Colorimetric sensing of sensor 1 is inclined to be deproton...

pI-Control in comparative fluorescence gel electrophoresis (CoFGE) using amphoteric azo dyes

Czech Academy of Sciences Publication Activity Database

Hanneken, M.; Šlais, Karel; König, S.

2015-01-01

Roč. 8, SEP (2015), s. 36-39 ISSN 2212-9685 Institutional support: RVO:68081715 Keywords : comparative fluorescence gel * electrophoresis * protein grid * azo dyes Subject RIV: CB - Analytical Chemistry, Separation http://ac.els-cdn.com/S2212968515000094/1-s2.0-S2212968515000094-main.pdf?_tid=7c92fa40-56e6-11e5-b36a-00000aab0f01&acdnat=1441798543_19612c0d7466780944bc4ae22173da92

Radiolysis of organic triphenylmethane, anthraquinone, xanthene, oxazine, thiazine, and azo dyes in polymers films

International Nuclear Information System (INIS)

Khabarov, V.N.; Kozlov, L.L.; Molin, A.A.; Mekhanik, T.V.

1989-01-01

The effect of the oxygen in the air and the temperature on radiochemical processes of decolorization of triphenylmethane, anthraquinone, xanthene, oxazine, thiazine, and azo dyes in polymer matrices of different chemical natures was studied. The rate of radiation decolorization for most of the dyes increases in irradiation in the presence of O 2 , which is hypothetically due to oxidation of the dye by singlet oxygen. The organic dyes exhibit the highest radiation stability in polyethylene terephthalate and polystyrene films

Synthesis, Spectral, Thermogravimetric, XRD, Molecular Modelling and Potential Antibacterial Studies of Dimeric Complexes with Bis Bidentate ON–NO Donor Azo Dye Ligands

Directory of Open Access Journals (Sweden)

Bipin Bihari Mahapatra

2013-01-01

Full Text Available The dimeric complexes of Co(II, Ni(II, Cu(II, Zn(II, Cd(II, and Hg(II with two new symmetrical ON–NO donor bis bidentate (tetradentate azo dye ligands, LH2 = 4,4′-bis(4′-hydroxyquinolinolinylazodiphenylsulphone, and L′H2 = 4,4′-bis(acetoacetanilideazodiphenylsulphone have been synthesized. The metal complexes have been characterised by elemental analytical, conductance, magnetic susceptibility, IR, electronic spectra, ESR, NMR, thermogravimetry, X-ray diffraction (powder pattern spectra, and molecular modelling studies. The Co(II and Ni(II complexes are found to be octahedral, Cu(II complexes are distorted octahedral, and a tetrahedral stereochemistry has been assigned to Zn(II, Cd(II, and Hg(II complexes. The thermogravimetric study indicates that compounds are quite stable. The energy optimized structures are proposed using the semiempirical ZINDO/1 quantum mechanical calculations. The potential antibacterial study of the ligands and some metal complexes has been made with one gram positive bacteria Staphylococcus aureus and one gram negative bacteria E. coli which gives encouraging results. Both the Co(II complexes are found to possess monoclinic crystal system.

Starch plus sunflower oil addition to the diet of dry dairy cows results in a trans-11 to trans-10 shift of biohydrogenation.

Science.gov (United States)

Zened, A; Enjalbert, F; Nicot, M C; Troegeler-Meynadier, A

2013-01-01

Trans fatty acids (FA), exhibit different biological properties. Among them, cis-9,trans-11 conjugated linoleic acid has some interesting putative health properties, whereas trans-10,cis-12 conjugated linoleic acid has negative effects on cow milk fat production and would negatively affect human health. In high-yielding dairy cows, a shift from trans-11 to trans-10 pathway of biohydrogenation (BH) can occur in the rumen of cows receiving high-concentrate diets, especially when the diet is supplemented with unsaturated fat sources. To study this shift, 4 rumen-fistulated nonlactating Holstein cows were assigned to a 4×4 Latin square design with 4 different diets during 4 periods. Cows received 12 kg of dry matter per day of 4 diets based on corn silage during 4 successive periods: a control diet (22% starch, diet supplemented with wheat plus barley (35% starch, diet supplemented with 5% of sunflower oil (20% starch, 7.6% crude fat), and a high-starch plus sunflower oil diet (33% starch, 7.3% crude fat). Five hours after feeding, proportions of trans-11 BH isomers greatly increased in the rumen content with the addition of sunflower oil, without change in ruminal pH compared with the control diet. Addition of starch to the control diet had no effect on BH pathways but decreased ruminal pH. The addition of a large amount of starch in association with sunflower oil increased trans-10 FA at the expense of trans-11 FA in the rumen content, revealing a trans-11 to trans-10 shift. Interestingly, with this latter diet, ruminal pH did not change compared with a single addition of starch. This trans-11 to trans-10 shift occurred progressively, after a decrease in the proportion of trans-11 FA in the rumen, suggesting that this shift could result from a dysbiosis in the rumen in favor of trans-10-producing bacteria at the expense of those producing trans-11 or a modification of bacterial activities. Copyright © 2013 American Dairy Science Association. Published by Elsevier

The Mitochondrial Genome of the Prasinophyte Prasinoderma coloniale Reveals Two Trans-Spliced Group I Introns in the Large Subunit rRNA Gene

Science.gov (United States)

Pombert, Jean-François; Otis, Christian; Turmel, Monique; Lemieux, Claude

2013-01-01

Organelle genes are often interrupted by group I and or group II introns. Splicing of these mobile genetic occurs at the RNA level via serial transesterification steps catalyzed by the introns'own tertiary structures and, sometimes, with the help of external factors. These catalytic ribozymes can be found in cis or trans configuration, and although trans-arrayed group II introns have been known for decades, trans-spliced group I introns have been reported only recently. In the course of sequencing the complete mitochondrial genome of the prasinophyte picoplanktonic green alga Prasinoderma coloniale CCMP 1220 (Prasinococcales, clade VI), we uncovered two additional cases of trans-spliced group I introns. Here, we describe these introns and compare the 54,546 bp-long mitochondrial genome of Prasinoderma with those of four other prasinophytes (clades II, III and V). This comparison underscores the highly variable mitochondrial genome architecture in these ancient chlorophyte lineages. Both Prasinoderma trans-spliced introns reside within the large subunit rRNA gene (rnl) at positions where cis-spliced relatives, often containing homing endonuclease genes, have been found in other organelles. In contrast, all previously reported trans-spliced group I introns occur in different mitochondrial genes (rns or coxI). Each Prasinoderma intron is fragmented into two pieces, forming at the RNA level a secondary structure that resembles those of its cis-spliced counterparts. As observed for other trans-spliced group I introns, the breakpoint of the first intron maps to the variable loop L8, whereas that of the second is uniquely located downstream of P9.1. The breakpoint In each Prasinoderma intron corresponds to the same region where the open reading frame (ORF) occurs when present in cis-spliced orthologs. This correlation between the intron breakpoint and the ORF location in cis-spliced orthologs also holds for other trans-spliced introns; we discuss the possible implications

The mitochondrial genome of the prasinophyte Prasinoderma coloniale reveals two trans-spliced group I introns in the large subunit rRNA gene.

Directory of Open Access Journals (Sweden)

Jean-François Pombert

Full Text Available Organelle genes are often interrupted by group I and or group II introns. Splicing of these mobile genetic occurs at the RNA level via serial transesterification steps catalyzed by the introns'own tertiary structures and, sometimes, with the help of external factors. These catalytic ribozymes can be found in cis or trans configuration, and although trans-arrayed group II introns have been known for decades, trans-spliced group I introns have been reported only recently. In the course of sequencing the complete mitochondrial genome of the prasinophyte picoplanktonic green alga Prasinoderma coloniale CCMP 1220 (Prasinococcales, clade VI, we uncovered two additional cases of trans-spliced group I introns. Here, we describe these introns and compare the 54,546 bp-long mitochondrial genome of Prasinoderma with those of four other prasinophytes (clades II, III and V. This comparison underscores the highly variable mitochondrial genome architecture in these ancient chlorophyte lineages. Both Prasinoderma trans-spliced introns reside within the large subunit rRNA gene (rnl at positions where cis-spliced relatives, often containing homing endonuclease genes, have been found in other organelles. In contrast, all previously reported trans-spliced group I introns occur in different mitochondrial genes (rns or coxI. Each Prasinoderma intron is fragmented into two pieces, forming at the RNA level a secondary structure that resembles those of its cis-spliced counterparts. As observed for other trans-spliced group I introns, the breakpoint of the first intron maps to the variable loop L8, whereas that of the second is uniquely located downstream of P9.1. The breakpoint In each Prasinoderma intron corresponds to the same region where the open reading frame (ORF occurs when present in cis-spliced orthologs. This correlation between the intron breakpoint and the ORF location in cis-spliced orthologs also holds for other trans-spliced introns; we discuss the

Ácidos graxos trans: implicações nutricionais e fontes na dieta Trans fatty acids: nutritional implications and sources in the diet

Directory of Open Access Journals (Sweden)

Clayton Antunes Martin

2004-09-01

Full Text Available Este artigo revisa as principais fontes de ácidos graxos trans na dieta e as implicações nutricionais da ingestão elevada destes isômeros. São apresentados resumidamente os métodos analíticos utilizados na identificação e quantificação dos ácidos graxos trans, sendo abordados as suas vantagens e desvantagens. Os alimentos que empregam gordura parcialmente hidrogenada na sua produção, são fontes importantes de isômeros trans na dieta da maior parte da população em países industrializados. Este estudo compara os níveis de ácidos graxos trans em gorduras hidrogenadas, margarinas e batatas frita, analisados em diversos países, incluindo o Brasil. Esta avaliação indica a presença de níveis elevados de isômeros trans em alimentos produzidos no Brasil.This article review the main sources of trans fatty acids in the diet and nutritional implications of the high intake of these isomers. Analytical methods for the identification and quantification of trans fatty acids are presented briefly with regard to advantages and drawbacks of each method. Foods make with partially hidrogenated fats are important sources of trans isomers in the diets of most people in industrialized countries. It is made a comparison between levels of trans fatty acids in shortenings, margarines and potato chips evaluated in Brazil and in other countries. High levels of trans isomers are noted in Brazilian foods.

Trans-nationalisation Processes in the Ukrainian Economy

OpenAIRE

Bolharova Natalya K.; Panevnyk Tetyana M.

2013-01-01

The article considers main processes of trans-nationalisation of Ukrainian economy, identifies specific features of trans-national production and explains some theoretical aspects of these issues. It provides main stages of theoretical comprehension of activity of trans-national corporations (TNC), specific features of the theory of competitive advantages of TNC and specifies the basic ones of them. The article conducts analysis of flows of direct foreign investments into the Ukrainian econom...

Finding a Trans-Affirmative Provider: Challenges Faced by Trans and Gender Diverse Psychologists and Psychology Trainees.

Science.gov (United States)

Dickey, Lore M; Singh, Anneliese A

2017-08-01

This article explores some of the challenges faced by trans and gender diverse (TGD) individuals who not only are attempting to access trans-affirmative care, but who are also members of the very profession from which they are seeking services. The authors explore challenges related to finding supervision, accessing care for assessment services, and finding a provider for personal counseling. With each example, the authors unpack the challenges and also address the implications for training for all involved. Based on these challenges that TGD psychologists and trainees face in attempting to access care, the authors provide recommendations related to trans-affirmative training for psychologists. © 2017 Wiley Periodicals, Inc.

Opposite photo-induced deformations in azobenzene-containing polymers with different molecular architecture: Molecular dynamics study

International Nuclear Information System (INIS)

Ilnytskyi, Jaroslav M.; Neher, Dieter; Saphiannikova, Marina

2011-01-01

Photo-induced deformations in azobenzene-containing polymers (azo-polymers) are central to a number of applications, such as optical storage and fabrication of diffractive elements. The microscopic nature of the underlying opto-mechanical coupling is yet not clear. In this study, we address the experimental finding that the scenario of the effects depends on molecular architecture of the used azo-polymer. Typically, opposite deformations in respect to the direction of light polarization are observed for liquid crystalline and amorphous azo-polymers. In this study, we undertake molecular dynamics simulations of two different models that mimic these two types of azo-polymers. We employ hybrid force field modeling and consider only trans-isomers of azobenzene, represented as Gay-Berne sites. The effect of illumination on the orientation of the chromophores is considered on the level of orientational hole burning and emphasis is given to the resulting deformation of the polymer matrix. We reproduce deformations of opposite sign for the two models being considered here and discuss the relevant microscopic mechanisms in both cases.

Spectroscopy of odd Z trans-fermium nuclei: the nuclear structure of Md251

International Nuclear Information System (INIS)

Chatillon, A.

2005-10-01

The objective of this thesis was to determine the structure of trans-fermium nuclei (Z 100) with odd proton number, which remained largely unexplored. These nuclei were produced in fusion-evaporation reactions with small cross sections below 1 μb. The experimental methods of Recoil-Tagging and Recoil-Decay-Tagging were used for their identification. In order to identify the active orbitals in this mass region, 255 Lr, 251 M1d and 247 Es nuclei have been studied by decay spectroscopy at the University of Jyvaskyla and at GANIL with the LISE spectrometer and the α-electron detector BEST coupled to four CLover detectors from the EXOGAM array. New states have been observed in each of the isotopes, and their configuration has been proposed. The collective properties were also studied in two experiments using prompt γ and electron spectroscopy, combining the JUROGAM and SACRED arrays, respectively, with the recoil separator RITU and the GREAT spectrometer at its focal plane. A rotational band has been observed for the first time in a proton-odd trans-fermium nucleus. The interpretation of this collective structure is based on the theoretical HFB calculations. (author)

Metabolism of trans, trans-muconaldehyde, a cytotoxic metabolite of benzene, in mouse liver by alcohol dehydrogenase Adh1 and aldehyde reductase AKR1A4

International Nuclear Information System (INIS)

Short, Duncan M.; Lyon, Robert; Watson, David G.; Barski, Oleg A.; McGarvie, Gail; Ellis, Elizabeth M.

2006-01-01

The reductive metabolism of trans, trans-muconaldehyde, a cytotoxic metabolite of benzene, was studied in mouse liver. Using an HPLC-based stopped assay, the primary reduced metabolite was identified as 6-hydroxy-trans, trans-2,4-hexadienal (OH/CHO) and the secondary metabolite as 1,6-dihydroxy-trans, trans-2,4-hexadiene (OH/OH). The main enzymes responsible for the highest levels of reductase activity towards trans, trans-muconaldehyde were purified from mouse liver soluble fraction first by Q-sepharose chromatography followed by either blue or red dye affinity chromatography. In mouse liver, trans, trans-muconaldehyde is predominantly reduced by an NADH-dependent enzyme, which was identified as alcohol dehydrogenase (Adh1). Kinetic constants obtained for trans, trans-muconaldehyde with the native Adh1 enzyme showed a V max of 2141 ± 500 nmol/min/mg and a K m of 11 ± 4 μM. This enzyme was inhibited by pyrazole with a K I of 3.1 ± 0.57 μM. Other fractions were found to contain muconaldehyde reductase activity independent of Adh1, and one enzyme was identified as the NADPH-dependent aldehyde reductase AKR1A4. This showed a V max of 115 nmol/min/mg and a K m of 15 ± 2 μM and was not inhibited by pyrazole

Synthesis of new liquid crystals embedded gold nanoparticles for photoswitching properties.

Science.gov (United States)

Rahman, Md Lutfor; Biswas, Tapan Kumar; Sarkar, Shaheen M; Yusoff, Mashitah Mohd; Yuvaraj, A R; Kumar, Sandeep

2016-09-15

A new series of liquid crystals decorated gold nanoparticles is synthesized whose molecular architecture has azobenzenes moieties as the peripheral units connected to gold nanoparticles (Au NPs) via alkyl groups. The morphology and mesomorphic properties were investigated by field emission scanning electron microscope, high-resolution transmission electron microscopy, differential scanning calorimetry and polarizing optical microscopy. The thiolated ligand molecules (3a-c) showed enantiotropic smectic A phase, whereas gold nanoparticles (5a-c) exhibit nematic and smectic A phase with monotropic nature. HR-TEM measurement showed that the functionalized Au NPs are of the average size of 2nm and they are well dispersed without any aggregation. The trans-form of azo compounds showed a strong band in the UV region at ∼378nm for the π-π(∗) transition, and a weak band in the visible region at ∼472nm due to the n-π(∗) transition. These molecules exhibit attractive photoisomerization behaviour in which trans-cis transition takes about 15s whereas the cis-trans transition requires about 45min for compound 5c. The extent of reversible isomerization did not decay after 10 cycles, which proved that the photo-responsive properties of 5c were stable and repeatable. Therefore, these materials may be suitably exploited in the field of molecular switches and the optical storage devices. Copyright © 2016 Elsevier Inc. All rights reserved.

Trans issues in Liz Lochhead's 'Not Changed'

OpenAIRE

Kaličanin Milena M.

2017-01-01

The paper is divided into four sections. In the first section entitled 'Introducing and Defining Trans (Issues)', the basic terms of transgender, transvestite, and transsexual are defined by relying on Stryker's Transgender History (2008). The second part of the paper, 'Trans Studies: In-Between Feminist and Queer Theory?', places transgender studies into an academic context by referring to the theoretical framework provided by trans theorists Stryker, Stone, and Ranck who unanimously claim t...

Trans fats in New Zealand: time for labelling regulations?

Science.gov (United States)

Gladding, Patrick; Benatar, Jocelyne R

2007-11-09

Trans fats (trans fatty acids) are commonly used for deep frying in restaurants and in the fast food, snack food, fried food, and baked goods industries, often to extend the shelf life of foods. However they are widely considered to be harmful to health. Trans fats were banned in New York City restaurants from 1 July 2007, and there is growing vocal opposition to trans fats in the European Union. Denmark became the first country, in March 2003, to introduce laws regulating the content of trans fats in food (maximum of 2% of edible fats and oils). What are trans fats, what harm do they cause, and should New Zealand also consider imposing mandatory regulations on their use in food? This article explores the issues.

Physics of Trans-Planckian Gravity

CERN Document Server

Dvali, Gia; Germani, Cristiano

2011-01-01

We study aspects of the phenomenon of gravitational UV-self-completeness and its implications for deformations of Einstein gravity. In a ghost-free theory flowing to Einstein gravity in the IR trans-Planckian propagating quantum degrees of freedom cannot exist. The only physical meaning of a trans-Planckian pole is the one of a classical state (Black Hole) which is fully described by the light IR quantum degrees of freedom and gives exponentially-suppressed contributions to virtual processes. In this sense Einstein gravity is UV self-complete, although not Wilsonian. We show that this UV/IR correspondence puts a severe constraint on any attempt of conventional Wilsonian UV-completion of trans-Planckian gravity. In particular, there is no well-defined energy domain in which gravity could become asymptotically weak or safe.

Is there such a thing as Tech Trans?

DEFF Research Database (Denmark)

Helms, Niels Henrik

2009-01-01

This short paper is an attempt to start a discussion on some basic issues within the concept of Tech Trans especially the relationship between flow and structure within the concept. The background to this paper is first of all an academic interest in the relationship between flow and structure...... explores the concept of Tech Trans, show rooms and innovation systems, and it suggests that the notion of Tech Trans should be defined in the fix point of vertical and horizontal innovation. Finally this paper suggests a mathematical formula for evaluating Tech Trans....

New probabilistic risk assessment of ethylhexyl methoxycinnamate: Comparing the genotoxic effects of trans- and cis-EHMC.

Science.gov (United States)

Nečasová, Anežka; Bányiová, Katarína; Literák, Jaromír; Čupr, Pavel

2017-02-01

Ethylhexyl methoxycinnamate (EHMC) is a widely used UV filter present in a large number of personal care products (PCPs). Under normal conditions, EHMC occurs in a mixture of two isomers: trans-EHMC and cis-EHMC in a ratio of 99:1. When exposed to sunlight, the trans isomer is transformed to the less stable cis isomer and the efficiency of the UV filter is reduced. To date, the toxicological effects of the cis-EHMC isomer remain largely unknown. We developed a completely new method for preparing cis-EHMC. An EHMC technical mixture was irradiated using a UV lamp and 98% pure cis-EHMC was isolated from the irradiated solution using column chromatography. The genotoxic effects of the isolated cis-EHMC isomer and the nonirradiated trans-EHMC were subsequently measured using two bioassays (SOS chromotest and UmuC test). In the case of trans-EHMC, significant genotoxicity was observed using both bioassays at the highest concentrations (0.5 - 4 mg mL -1 ). In the case of cis-EHMC, significant genotoxicity was only detected using the UmuC test at concentrations of 0.25 - 1 mg mL -1 . Based on these results, the NOEC was calculated for both cis- and trans-EHMC, 0.038 and 0.064 mg mL -1 , respectively. Risk assessment of dermal, oral and inhalation exposure to PCPs containing EHMC was carried out for a female population using probabilistic simulation and by using Quantitative in vitro to in vivo extrapolation (QIVIVE). The risk of cis-EHMC was found to be ∼1.7 times greater than trans-EHMC. In the case of cis-EHMC, a hazard index of 1 was exceeded in the 92nd percentile. Based on the observed differences between the isomers, EHMC application in PCPs requires detailed reassessment. Further exploration of the toxicological effects and properties of cis-EHMC is needed in order to correctly predict risks posed to humans and the environment. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 569-580, 2017. © 2016 Wiley Periodicals, Inc.

Decolorization of azo dye and generation of electricity by microbial fuel cell with laccase-producing white-rot fungus on cathode

International Nuclear Information System (INIS)

Lai, Chi-Yung; Wu, Chih-Hung; Meng, Chui-Ting; Lin, Chi-Wen

2017-01-01

Highlights: • A laccase-producing fungus on cathode of MFC was used to enhance degradation of azo dye. • Laccase-producing fungal cathodes performed better than laccase-free control cathodes. • A maximum power density of 13.38 mW/m"2 and an >90% decolorization of acid orange 7 were obtained. • Growing a fungal culture with continuous laccase production improved MFC’s electricity generation. - Abstract: Wood-degrading white-rot fungi produce many extracellular enzymes, including the multi-copper oxidative enzyme laccase (EC 1.10.3.2). Laccase uses atmospheric oxygen as the electron acceptor to catalyze a one-electron oxidation reaction of phenolic compounds and therefore has the potential to simultaneously act as a cathode catalyst in a microbial fuel cell (MFC) and degrade azo dye pollutants. In this study, the laccase-producing white-rot fungus Ganoderma lucidum BCRC 36123 was planted on the cathode surface of a single-chamber MFC to degrade the azo dye acid orange 7 (AO7) synergistically with an anaerobic microbial community in the anode chamber. In a batch culture, the fungus used AO7 as the sole carbon source and produced laccase continuously, reaching a maximum activity of 20.3 ± 0.3 U/L on day 19 with a 77% decolorization of the dye (50 mg/L). During MFC operations, AO7 in the anolyte diffused across a layer of polyvinyl alcohol-hydrogel that separated the cathode membrane from the anode chamber, and served as a carbon source to support the growth of, and production of laccase by, the fungal mycelium that was planted on the cathode. In such MFCs, laccase-producing fungal cathodes outperformed laccase-free controls, yielding a maximum open-circuit voltage of 821 mV, a closed-circuit voltage of 394 mV with an external resistance of 1000 Ω, a maximum power density of 13.38 mW/m"2, a maximum current density of 33 mA/m"2, and a >90% decolorization of AO7. This study demonstrates the feasibility of growing a white-rot fungal culture with continuous

Trans issues in Liz Lochhead's 'Not Changed'

Directory of Open Access Journals (Sweden)

Kaličanin Milena M.

2017-01-01

Full Text Available The paper is divided into four sections. In the first section entitled 'Introducing and Defining Trans (Issues', the basic terms of transgender, transvestite, and transsexual are defined by relying on Stryker's Transgender History (2008. The second part of the paper, 'Trans Studies: In-Between Feminist and Queer Theory?', places transgender studies into an academic context by referring to the theoretical framework provided by trans theorists Stryker, Stone, and Ranck who unanimously claim that transgender studies should have a place of its own within the academia and that trans theory should solely be written by transsexuals. These ideas are applied in the interpretation of Lochhead's story 'Not Changed' in the third segment of the paper. The critical insights of Butler (Gender Trouble, 1990; Undoing Gender, 2004 are found to be most helpful in the interpretation of Lochhead's story about Michael who has willingly undergone Hormone Replacement Therapy to become transsexual Michele. Finally, in the concluding remarks, Lochhead's story is viewed as a trans woman manifesto, urging both non-transsexual and transsexual persons to embrace new beginnings in their relationship.

Trans-nationalisation Processes in the Ukrainian Economy

Directory of Open Access Journals (Sweden)

Bolharova Natalya K.

2013-12-01

Full Text Available The article considers main processes of trans-nationalisation of Ukrainian economy, identifies specific features of trans-national production and explains some theoretical aspects of these issues. It provides main stages of theoretical comprehension of activity of trans-national corporations (TNC, specific features of the theory of competitive advantages of TNC and specifies the basic ones of them. The article conducts analysis of flows of direct foreign investments into the Ukrainian economy. It shows distribution of direct foreign investments into Ukraine by main countries-investors, regions-recipients and types of economic activity. It conducts review and analysis of the modern state of trans-national corporations of foreign origin in the Ukrainian market. It considers functioning of domestic TNC in Ukraine and main tendencies of entering of Ukrainian companies into the world environment and also identifies directions of further development of these phenomena. Prospects of further studies in this direction are identification of the degree of trans-nationalisation processes in the Ukrainian economy and identification of the positive effect, in particular, synergy from integration and globalisation.

Crystal structure of {2,2′-[N,N′-bis(pyridin-2-ylmethylcyclohexane-trans-1,2-diyldi(nitrilo]diacetato}cobalt(III hexafluoridophosphate

Directory of Open Access Journals (Sweden)

Craig C. McLauchlan

2015-04-01

Full Text Available The title compound [Co(C22H26N4O4]PF6, commonly known as [Co(bpcd]PF6, where bpcd2− is derived from the historical ligand name N,N′-bis(2-pyridylmethyl-trans-1,2-diaminocyclohexane-N,N′-diacetate, crystallized by slow evaporation of a saturated acetonitrile solution in air. The cation of the hexafluoridophosphate salt has the CoIII atom in a distorted octahedral coordination geometry provided by an N4O2 donor atom set. The acetate groups, which are oriented trans with respect to each other, exhibit monodentate coordination whereas the pyridyl N atoms are coordinating in a cis configuration. The geometry of the cation is compared to the geometries of other diamino diacetate complexes with CoIII.

Formation of trans fats during food preparation.

Science.gov (United States)

Przybylski, Oman; Aladedunye, Felix A

2012-01-01

An investigation was completed to determine how typical cooking procedures used in food preparation, such as baking and stir-frying, affect trans fats formation. Canola oil was used as the main fat ingredient. Zucchini cake and gingersnap cookies were baked at 180o C and 200o C, while stir-fried chicken was prepared at 200o C and 275o C. The lipids from the food were extracted following the Folch procedure, and analyzed for trans fatty acids according to ISO official method 15304. Minimal changes were observed in the amount of trans fats during baking. Application of extreme temperatures during baking, which caused carbonization of the outer layer of products, yielded an insignificant increase in the amount of trans isomers. As with baking, stir-frying did not result in significant isomerization of the fatty acids, even when the oil was heated to 275o C and smoking heavily before the food was placed in it. Irrespective of the cooking procedure, linolenic acid was the most prone to isomerization with the highest amount of trans isomers formation. Baking and stir-frying at normal and/or extreme temperatures do not significantly affect the amounts of trans fats. Likewise, heating oil to the smoking point during stir-frying may decrease the amount of polyunsaturated fatty acids because of oxidative degradation.

Binge-type behavior in rats consuming trans-fat-free shortening.

Science.gov (United States)

Wojnicki, F H E; Charny, G; Corwin, R L W

2008-07-05

Studies from this and another laboratory involving an animal model of binge-type behavior have used vegetable shortening containing trans-fats. Due to reformulations by vegetable shortening manufacturers to remove trans-fats from their products, only trans-fat-free shortenings are now available. The goal of the present study was to assess binge-type behavior in rats with trans-fat and trans-free vegetable shortening. Trans-fat-free shortening was provided to three different groups of non-food-deprived male Sprague Dawley rats on different schedules of access: continuous access (24 h/day-7 days/week), daily access (1 h every day), and intermittent access (1 h on Mondays, Wednesdays, Fridays). Trans-fat shortening was provided to a fourth group on the intermittent access schedule. A fifth group had no shortening access (chow only). Both intermittent groups (trans-fat-free and trans-fat) consumed significantly more shortening during the 1-h period of availability than did the daily group, and there was no difference in shortening intakes between the intermittent groups. These results are identical to previous reports of binge-type behavior in rats using this model. Thus, binge-type behavior in the present behavioral model depends upon the schedule of access, not the presence of trans-fats in the shortening.

Cis-trans photoisomerization of abscisic acid

International Nuclear Information System (INIS)

Brabham, D.E.; Biggs, R.H.

1981-01-01

An important regulator of numerous physiological processes in higher plants is abscisic acid (ABA), which is photoisomerized from the more biologically active cis isomer to the nearly inactive trans isomer by natural sunlight. It is possible that this photoisomerization is a UV control mechanism in functions regulated by ABA. The quantum yields of both the cis to trans and trans to cis photoisomerizations were measured under various conditions of pH and oxygen concentration at room temperature. The yield for photoisomerization of cis-ABA ranged from 0.25 at pH 3.0 to 0.11 at pH 7.0. Oxygen partially quenched the process. The quantum yield varied only slightly with wavelength. The quantum yield of photolysis of cis-ABA was reported for pH 3.0 as 0.06. This yield also varied slightly with wavelength and was relatively insensitive to oxygen. This relatively high yield explains the loss of potency of ABA during UV irradiation. Phosphorescence of cis- and trans-ABA was observed in methanol at 77 K. Onset of the emission was at 350 nm. The emission spectra were the same for both isomers. From these results a mechanism of UV action on plants based on the photoisomerization of the inactive trans-ABA to the biologically active cis isomer is proposed. (author)

[CONTENT OF TRANS FATTY ACIDS IN FOOD PRODUCTS IN SPAIN].

Science.gov (United States)

Robledo de Dios, Teresa; Dal Re Saavedra, M Ángeles; Villar Villalba, Carmen; Pérez-Farinós, Napoleón

2015-09-01

trans fatty acids are associated to several health disorders, as ischemic heart disease or diabetes mellitus. to assess the content of trans fatty acids in products in Spain, and the percentage of trans fatty acids respecting total fatty acids. 443 food products were acquired in Spain, and they were classified into groups. The content in fatty acids was analyzed using gas chromatography. Estimates of central tendency and variability of the content of trans fatty acids in each food group were computed (in g of trans fatty acids/100 g of product). The percentage of trans fatty acids respecting total fatty acids was calculated in each group. 443 products were grouped into 42 groups. Median of trans fatty acids was less than 0.55 g / 100 g of product in all groups except one. 83 % of groups had less than 2 % of trans fatty acids, and 71 % of groups had less than 1 %. the content of trans fatty acids in Spain is low, and it currently doesn't play a public health problem. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.

Dark halos and elliptical galaxies as marginally stable dynamical systems

Energy Technology Data Exchange (ETDEWEB)

El Zant, A. A. [Centre for Theoretical Physics, Zewail City of Science and Technology, Sheikh Zayed, 12588 Giza (Egypt); The British University in Egypt, Sherouk City, Cairo 11837 (Egypt)

2013-12-10

The origin of equilibrium gravitational configurations is sought in terms of the stability of their trajectories, as described by the curvature of their Lagrangian configuration manifold of particle positions—a context in which subtle spurious effects originating from the singularity in the two-body potential become particularly clear. We focus on the case of spherical systems, which support only regular orbits in the collisionless limit, despite the persistence of local exponential instability of N-body trajectories in the anomalous case of discrete point particle representation even as N → ∞. When the singularity in the potential is removed, this apparent contradiction disappears. In the absence of fluctuations, equilibrium configurations generally correspond to positive scalar curvature and thus support stable trajectories. A null scalar curvature is associated with an effective, averaged equation of state describing dynamically relaxed equilibria with marginally stable trajectories. The associated configurations are quite similar to those of observed elliptical galaxies and simulated cosmological halos and are necessarily different from the systems dominated by isothermal cores, expected from entropy maximization in the context of the standard theory of violent relaxation. It is suggested that this is the case because a system starting far from equilibrium does not reach a 'most probable state' via violent relaxation, but that this process comes to an end as the system finds and (settles in) a configuration where it can most efficiently wash out perturbations. We explicitly test this interpretation by means of direct simulations.

Trans-nationalizing the African Public Sphere: What Role for Trans ...

African Journals Online (AJOL)

seriane.camara

2011-03-09

Mar 9, 2011 ... At a time when the notion of 'trans-national public spheres' is gaining .... ple refer specifically to the language and its speakers in Senegal and Mauri- .... of the Pulaar language and the improvement of the social and economic.

Peel Region TransHelp's experience

Energy Technology Data Exchange (ETDEWEB)

NONE

2009-09-15

TransHelp was founded in the Peel Region of Ontario in 1981 to provide paratransit service to individuals unable to use conventional transit. The TransHelp vehicle fleet consists of 40 buses that make over 220,000 one way trips annually. Each vehicle has a typical life span of between 375,000 and 425,000 km. TransHelp vehicles spend much of their time idling in emissions-sensitive areas, such as outside hospitals. In order to reduce fuel costs, TransHelp adopted the use of propane to fuel its vehicles. However, difficulties were experienced with this technology, particularly on V-10 engines where increased maintenance was a problem. SFI Technologies Inc. provided a solution with their SEQUIN System which allows seamless transitioning between gasoline and propane under all conditions without any operator involvement in fuel selection. The technology favours propane as the fuel of choice and automatically switches between propane and gasoline based on the ideal conditions at the time of operation. The technology has received certification from the Environmental Protection Agency in the United States and the Canadian Standards Association. The use of the SEQUIN System has proven to successful for TransHelp. It has allowed the use of propane to be continued, meaning that vehicle emissions are greatly reduced relative to gasoline or diesel fuelled vehicles. TransHelp has realized a fuel savings of 15-20 per cent over gasoline and receives an additional federal transit rebate of 15 per cent for the conversion cost.

Trans Women Doing Sex in San Francisco.

Science.gov (United States)

Williams, Colin J; Weinberg, Martin S; Rosenberger, Joshua G

2016-10-01

This research investigates the sexuality of trans women (individuals who were assigned male status at birth who currently identify as women), by focusing on the "bodily techniques" (Crossley, 2006) they use in "doing" sexuality. The "doing sexuality" framework not only is modeled after the "doing gender" approach of West and Zimmerman (1987), but also utilizes the idea of "sexual embodiment" to emphasize the agency of trans women as they conceptualize and organize their sexuality in a socially recognized way. This is often difficult as they confront discrimination from medical and legal professionals as well as intimate partners who may find it difficult to adapt to the trans woman's atypical body and conception of gender. However, with a study group of 25 trans women from San Francisco, we found the study participants to be adept at overcoming such hurdles and developing techniques to "do" their sexuality. At the same time, we found trans women's agency constrained by the erotic habitus (Green, 2008) of the wider society. The interplay between innovation and cultural tradition provides an opportunity to fashion a more general model of "doing" sexuality.

Repair Activity of trans-Resveratrol toward 2'-Deoxyguanosine Radicals.

Science.gov (United States)

Cheng, Xing; An, Ping; Li, Shujin; Zhou, Liping

2018-04-26

In the present study, the repair activity of trans-resveratrol toward 2'-deoxyguanosine (dGuo) radicals in polar and nonpolar solvents was studied using density functional theory. The hydrogen transfer/proton coupled electron transfer and single electron transfer (SET) mechanisms between trans-resveratrol and dGuo-radicals were considered. Taking into consideration the molar fraction of neutral trans-resveratrol (ROH) and anionic trans-resveratrol (RO - ), the overall rate constants for repairing dGuo-radicals by trans-resveratrol are 9.94 × 10 8 and 2.01 × 10 9 dm 3 mol -1 s -1 in polar and nonpolar solvents, respectively, and the overall rate constant of repairing cation radical (dGuo •+ ) by trans-resveratrol via an SET mechanism is 7.17 × 10 9 dm 3 mol -1 s -1 . The repair activity of RO - toward dGuo-radicals is better than that of ROH, but the repair activity of ROH toward dGuo •+ is better than that of RO - . Unfortunately, neither ROH nor RO - can repair the 2'-deoxyribose radicals of dGuo. It can therefore be concluded that trans-resveratrol is an effective antioxidant for repairing base radicals of dGuo and dGuo •+ . The study can help us understand the repair activity of trans-resveratrol toward dGuo radicals.

FACTS ABOUT TRANS FATTY ACIDS

Directory of Open Access Journals (Sweden)

Sedighe Asgary

2010-12-01

Full Text Available Introduction Fatty acids constitute the main class of lipids in the human diet, being found in nature mainly as glycerol esters that originate triacylglycerols. In the vegetal and animal kingdoms, fatty acids generally have cis unsaturations. In this form, the hydrogens bound to the double bond carbons are on the same side. In another possible configuration, called trans, the hydrogens are bound to un saturations, carbons on opposing sides. Fatty acids with one or more un saturations in the trans configuration are called trans fatty acids (TFAs.1-4      There are two major sources of TFA, those that come from ruminant animals and those that are industrially produced.      The majority of TFAs are found in partially hydrogenated vegetable oils, which contain 10–40% as TFA.5 Hydrogenation is based on the reaction of unsaturated fatty acids of either vegetable or marine oil in the presence of a catalyst, in general nickel. The objective is to increase the oxidative stability of oils by reduction of the concentration of more unsaturated fatty acids and changing their physical properties, thus extending their application. Hydrogenation depends mainly on oil temperature, hydrogen pressure, stirring speed, reaction time, and the catalyst type and concentration. According to the process conditions, hydrogenation is classified as either partial or total and either selective or nonselective.6 It has been estimated that dietary TFAs from partially hydrogenated oils may be responsible for between 30,000 and 100,000 premature coronary deaths per year in the United States.7      The concentration of TFA in meat and milk from ruminants (i.e., cattle, sheep, goats, etc. contain 3 to 8% of total fat.5 It is hypothesized that ruminant TFAs, or certain TFA isomers from ruminant sources, may confer some health benefits; however, since TFA from animal sources accompany saturated fatty acids (SFA, an increase in a single ruminant TFA in the diet is not

The importance of trans-generational effects in Lepidoptera.

Science.gov (United States)

Woestmann, Luisa; Saastamoinen, Marjo

2016-10-01

The importance of trans-generational effects in shaping an individuals' phenotype and fitness, and consequently even impacting population dynamics is increasingly apparent. Most of the research on trans-generational effects still focuses on plants, mammals, and birds. In the past few years, however, increasing number of studies, especially on maternal effects, have highlighted their importance also in many insect systems. Lepidoptera, specifically butterflies, have been used as model systems for studying the role of phenotypic plasticity within generations. As ectotherms, they are highly sensitive to environmental variation, and indeed many butterflies show adaptive phenotypic plasticity in response to environmental conditions. Here, we synthesize what is known about trans-generational effects in Lepidoptera, compile evidence for different environmental cues that are important drivers of trans-generational effects, and point out which offspring traits are mainly impacted. Finally, we emphasize directions for future research that are needed for better understanding of the adaptive nature of trans-generational effects in Lepidoptera in particular, but potentially also in other organisms.

Synthesis of mutual azo prodrugs of anti-inflammatory agents and peptides facilitated by α-aminoisobutyric acid.

Science.gov (United States)

Kennedy, David A; Vembu, Nagarajan; Fronczek, Frank R; Devocelle, Marc

2011-12-02

Reported is the synthesis of azo mutual prodrugs of the nonsteroidal anti-inflammatory agents (NSAIDs) 4-aminophenylacetic acid (4-APAA) or 5-aminosalicylic acid (5-ASA) with peptides, including an antibiotic peptide temporin analogue modified at the amino terminal by an α-aminoisobutyric acid (Aib) residue. These prodrugs are designed for colonic delivery of two agents to treat infection and inflammation by the bacterial pathogen Clostridium difficile . © 2011 American Chemical Society

Iron promotion of the TiO2 photosensitization process towards the photocatalytic oxidation of azo dyes under solar-simulated light irradiation

International Nuclear Information System (INIS)

Castro, Camilo A.; Centeno, Aristobulo; Giraldo, Sonia A.

2011-01-01

Highlights: → Azo dye photooxidation occurs under strict combination of ultraviolet and visible irradiation of Fe-TiO 2 . → Fe 3+ enhances the TiO 2 photooxidation of azo dyes while decreases that of phenol. → UV irradiation leads to a decrease in photooxidation activity of Fe-TiO 2 photocatalysts. - Abstract: The photocatalytic oxidation of the azo dye Orange-II (Or-II) using Fe loaded TiO 2 (Fe-TiO 2 ) was studied under ultraviolet (UV), visible (vis) and simultaneous UV-vis irradiations using a solar light simulator. Photocatalysts were characterized by means of XRD, SEM-EDX, FTIR and DRS. Fe 3+ species, identified in XPS analyses, were responsible of the increased absorption of visible light. Moreover, DRS analyses showed a decrease in the bandgap due to Fe 3+ loading. Photocatalystic tests proved that Fe modification enhanced the TiO 2 photocatalytic activity towards Or-II photodegradation under simultaneous UV-vis irradiation. Even so, the performance of the Fe-TiO 2 samples towards the photodegradation of phenol, under UV irradiation, was lower than TiO 2 suggesting the recombination of the UV photogenerated electron-hole pair. Therefore, results evidence a Fe 3+ promotion of the electron caption in the photosensitization process of TiO 2 by Or-II acting as a sensitizer. Such process leads to the Or-II photooxidation under UV-vis irradiation by losing energy in electron transferring processes to sensitize TiO 2 , and, the formation of reactive oxygen species promoted by the injected electron to the TiO 2 conduction band.

Development of a GAL4-VP16/UAS trans-activation system for tissue specific expression in Medicago truncatula.

Directory of Open Access Journals (Sweden)

Amélie Sevin-Pujol

Full Text Available Promoters with tissue-specific activity are very useful to address cell-autonomous and non cell autonomous functions of candidate genes. Although this strategy is widely used in Arabidopsis thaliana, its use to study tissue-specific regulation of root symbiotic interactions in legumes has only started recently. Moreover, using tissue specific promoter activity to drive a GAL4-VP16 chimeric transcription factor that can bind short upstream activation sequences (UAS is an efficient way to target and enhance the expression of any gene of interest. Here, we developed a collection of promoters with different root cell layers specific activities in Medicago truncatula and tested their abilities to drive the expression of a chimeric GAL4-VP16 transcription factor in a trans-activation UAS: β-Glucuronidase (GUS reporter gene system. By developing a binary vector devoted to modular Golden Gate cloning together with a collection of adapted tissue specific promoters and coding sequences we could test the activity of four of these promoters in trans-activation GAL4/UAS systems and compare them to "classical" promoter GUS fusions. Roots showing high levels of tissue specific expression of the GUS activity could be obtained with this trans-activation system. We therefore provide the legume community with new tools for efficient modular Golden Gate cloning, tissue specific expression and a trans-activation system. This study provides the ground work for future development of stable transgenic lines in Medicago truncatula.

Azo dyes degradation using TiO2-Pt/graphene oxide and TiO2-Pt/reduced graphene oxide photocatalysts under UV and natural sunlight irradiation

Science.gov (United States)

Rosu, Marcela-Corina; Coros, Maria; Pogacean, Florina; Magerusan, Lidia; Socaci, Crina; Turza, Alexandru; Pruneanu, Stela

2017-08-01

The photocatalytic degradation of azo dyes with different structures (amaranth, sunset yellow and tartrazine) using TiO2-Pt nanoparticles (TPt), TiO2-Pt/graphene oxide (TPt-GO) and TiO2-Pt/reduced graphene oxide (TPt-rGO) composites were investigated in the presence of UV and natural sunlight irradiation. The composites were prepared by a combined chemical-thermal method and characterized by Transmission Electron Microscopy (TEM), X-ray powder diffraction (XRD), Infrared (FTIR) and UV-Vis spectroscopy. The modification of TiO2-Pt with graphene oxide shifted its optical absorption edge towards the visible region and increased its photocatalytic activity under UV and natural sunlight irradiation. The efficiency of catalysts on azo dyes degradation (in similar conditions) reached high values (above 99%) under sunlight conditions, proving the remarkable photocatalytic activities of obtained composites. TPt-GO nanocomposite exhibited higher photoactivity than TPt or TPt-rGO, demonstrating degradation efficiencies of 99.56% for amaranth, 99.15% for sunset yellow and 96.23% for tartrazine. The dye photodegradation process follows a pseudo-first-order kinetic with respect to the Langmuir-Hinshelwood reaction mechanism. A direct dependence between azo dyes degradation rate and chemical structure of dyes has been observed.

Cancer risk assessment of azo dyes and aromatic amines from tattoo bands, folders of paper, toys, bed clothes, watch straps and ink

NARCIS (Netherlands)

Zeilmaker MJ; van Kranen HJ; van Veen MP; Janus J; LBM

2000-01-01

Dit rapport beschrijft een schatting voor het risico op kanker dat verbonden is aan het gebruik van tatoe bandjes, kinderspeelpapier, speelgoed, beddengoed, lederen horlogebandjes en inkt waarin kankerverwekkende azo kleurstoffen aangetroffen zijn. In genoemde producten zijn benzidine en de

Adaptive Sniping for Volatile and Stable Continuous Double Auction Markets

Science.gov (United States)

Toft, I. E.; Bagnall, A. J.

This paper introduces a new adaptive sniping agent for the Continuous Double Auction. We begin by analysing the performance of the well known Kaplan sniper in two extremes of market conditions. We generate volatile and stable market conditions using the well known Zero Intelligence-Constrained agent and a new zero-intelligence agent Small Increment (SI). ZI-C agents submit random but profitable bids/offers and cause high volatility in prices and individual trader performance. Our new zero-intelligence agent, SI, makes small random adjustments to the outstanding bid/offer and hence is more cautious than ZI-C. We present results for SI in self-play and then analyse Kaplan in volatile and stable markets. We demonstrate that the non-adaptive Kaplan sniper can be configured to suit either market conditions, but no single configuration is performs well across both market types. We believe that in a dynamic auction environment where current or future market conditions cannot be predicted a viable sniping strategy should adapt its behaviour to suit prevailing market conditions. To this end, we propose the Adaptive Sniper (AS) agent for the CDA. AS traders classify sniping opportunities using a statistical model of market activity and adjust their classification thresholds using a Widrow-Hoff adapted search. Our AS agent requires little configuration, and outperforms the original Kaplan sniper in volatile and stable markets, and in a mixed trader type scenario that includes adaptive strategies from the literature.

Photoresponsive smart surface of LC azo-dendrimer: photomanipulation of topological structures and real-time imaging at a nano-scale

Science.gov (United States)

Araoka, Fumito; Eremin, Alexey; Aya, Satoshi; Lee, Guksik; Ito, Atsuki; Nadasi, Hajnalka; Sebastian, Nerea; Ishikawa, Ken; Haba, Osamu; Stannarius, Ralf; Yonetake, Koichiro; Takezoe, Hideo

2017-02-01

In this paper, we review some results on our recent studies on photo-induced phenomena of liquid crystals (LCs) by means of interfaces decorated with a photo-responsive azobenzene dendrimer (azo-dendrimer). The azo-dendrimer molecules doped in a LC are spontaneously segregated from bulk and adsorbed onto substrate/LC or solvent/LC interfaces, and their photo-isomerization can bring about the so-called anchoring transition, i.e. reversible switching between homeotropic and planar alignment states of the bulk LC, when exposed to UV/VIS light. In addition to photoinduced anchoring transition in a LC cell, several interesting photo-induced phenomena through the azo-dendrimerdecorated interfaces have been reported, such as photo-induced transformation of the interior topological structures of nematic, cholesteric and smectic droplets, photo-mechanical motion of the micro particles dispersed in a nematic matrix, and optical assistance of the athermal anchoring transition with the aid of a perfluoropolymer surface. In addition to such phenomena, we also discuss the conditions of such photo-responsive interfaces in terms of the polar anchoring energy at the interface upon photo-isomerization under illumination of UV and/or VIS lights. The anisotropy of the polar anchoring energy was evaluated experimentally by means of Polarization Microscopy (POM), Dielectric Spectroscopy (DS), Second Harmonic Generation (SHG), and Attenuated Total Reflection Fourier Transform Infrared (ATR-IR) Spectroscopy, and theoretically based on the simple Rapini-Papoular model. We also demonstrate the continuous bulk orientation change by the photo-dynamic process through the fine control of the polar anchoring energy. Besides, the state-of-the-art video-rate atomic force microscopy (ν-AFM) was carried out to visualize the dynamics of such interfaces at a nano-meter scale.

Sexualidade e experiências trans: do hospital à alcova Sexuality and trans experiences: from the hospital to the bedroom

Directory of Open Access Journals (Sweden)

Berenice Bento

2012-10-01

Full Text Available Depois dos estudos das masculinidades, não é possível pensar a produção das identidades de gênero sem referenciá-las ao caráter relacional. Esta mudança deveu-se à incorporação da perspectiva relacional nesse campo de estudos e à crítica ao conceito de gênero assentado em uma suposta natureza feminina e masculina para construir as interpretações sobre o lugar dos corpos da ordem de gênero. Os objetivos desse artigo são: 1 apontar como um determinado conceito de gênero pode visibilizar múltiplas expressões de gênero, a exemplo das identidades trans (transexuais, travestis, cross dress, drag queen, drag king, transgêneros ou invisibilizá-las e contribuir para sua patologização. O segundo objetivo será apresentar narrativas de homens trans e de mulheres trans, que nos contarão suas vivências sexuais. Os saberes médicos-psi advogam a inexistência de sexualidade em seus corpos, sendo este um dos indicadores para produção do diagnóstico de transexua­lidade. Tentarei argumentar que a base teórica que sustenta a patologização das identidades trans e a afirmação que as pessoas trans são assexuadas tem como fundamento uma concepção que atrela e condiciona as identidades de gênero às estruturas biológicas.In the aftermath of studies on masculinity, it is impossible to consider the production of gender identities without linking them to the relationship aspect. This change was due to the incorporation of the relationship perspective in this field of study and criticism of the concept of gender founded upon an alleged concept of femininity and masculinity to create interpretations of the place of bodies in the gender order. The objectives of this paper are: 1 to show how a given concept of gender can render multiple expressions of gender visible, like the trans identities (transsexuals, transvestites, cross dressers, drag queens, drag kings, transgenders or sublimate them and contribute to their pathologization

Optical, thermal and combustion properties of self-colored polyamide nanocomposites reinforced with azo dye surface modified ZnO nanoparticles

Science.gov (United States)

Hajibeygi, Mohsen; Shabanian, Meisam; Omidi-Ghallemohamadi, Mehrdad; Khonakdar, Hossein Ali

2017-09-01

New self-colored aromatic-polyamide (PA) nanocomposites containing azo and naphthalene chromophores were prepared with azo-dye surface-modified ZnO nanoparticles (SMZnO) using solution method in dimethylformamide. The X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM) results showed the uniform distribution for ZnO nanoparticles in the PA matrix. The UV-vis spectra of PA/ZnO nanocomposites (PANC) showed a blue shift as well as reduction in absorbance intensities and the photoluminescence studies revealed that the increasing intensities of the violet emission in SMZnO loading. From thermo gravimetric analysis (TGA), the temperature at 10% mass loss (T10) increased from 291.8 °C to 387.6 °C for PANC containing 8 mass% of SMZnO, as well as the char yield enhanced significantly, which was about 23.5% higher than the neat PA. The peak heat release rate resulted from microscale combustion calorimeter (MCC), by 8 mass% loading of SMZnO, decreased about 56.9% lower than the neat PA.

Experimental investigation of undesired stable equilibria in pumpkin shape super-pressure balloon designs

Science.gov (United States)

Schur, W. W.

2004-01-01

Excess in skin material of a pneumatic envelope beyond what is required for minimum enclosure of a gas bubble is a necessary but by no means sufficient condition for the existence of multiple equilibrium configurations for that pneumatic envelope. The very design of structurally efficient super-pressure balloons of the pumpkin shape type requires such excess. Undesired stable equilibria in pumpkin shape balloons have been observed on experimental pumpkin shape balloons. These configurations contain regions with stress levels far higher than those predicted for the cyclically symmetric design configuration under maximum pressurization. Successful designs of pumpkin shape super-pressure balloons do not allow such undesired stable equilibria under full pressurization. This work documents efforts made so far and describes efforts still underway by the National Aeronautics and Space Administration's Balloon Program Office to arrive on guidance on the design of pumpkin shape super-pressure balloons that guarantee full and proper deployment.

Are Fast Food “Trans-Fat” Claims True? An Infraspec VFA-IR Spectrometer Analysis of Trans-fat content in select food items purchased from Long John Silver’s

Directory of Open Access Journals (Sweden)

Sharron Jenkins

2014-10-01

Full Text Available Studies linking high trans-fat diets to coronary heart disease (CHD have prompted the need to regulate, limit, or completely ban trans-fat from all commercial food products, including fast foods. Many U.S. fast food chains now claim that their food items, particularly French fries, have "no trans-fat". In a previous study, our lab tested the validity of trans-fat claims made by several popular fast food restaurants by experimentally determining the %trans-fat in oil extracted from fast food French fries. In some cases, the trans-fat content was nearly twice as high as the amount reported by the restaurant in their literature. Long John Silver's, for example, reported a trans-fat content of 25% for their French fries, while our lab actually found over 40% trans-fat. The purpose of this study is to broaden our study of Long John Silver's trans-fat claims by analyzing a variety of their food items and comparing our findings with the %trans-fat reported by the restaurant literature (nutrition fact tables. Variable Filter Array (VFA IR spectroscopy was used to assess the trans-fat content of oil extracted from food samples. Our preliminary findings suggest that nearly every food item under study contained considerably more trans-fat than the amount reported in the restaurant’s literature.

FIA-Spectrophotometric Method for Determination of Nitrite in Meat Products: An Experiment Exploring Color Reduction of an Azo-Compound

Science.gov (United States)

Penteado, Jose C.; Angnes, Lucio; Masini, Jorge C.; Oliveira, Paulo C. C.

2005-01-01

This article describes the reaction between nitrite and safranine O. This sensitive reaction is based on the disappearance of color of the reddish-orange azo dye, allowing the determination of nitrite at the mg mL-1 level. A factorial optimization of parameters was carried out and the method was applied for the quantification of nitrite in…

Biosurfactant production from Pseudomonas taiwanensis L1011 and its application in accelerating the chemical and biological decolorization of azo dyes.

Science.gov (United States)

Liu, Cong; You, Yanting; Zhao, Ruofei; Sun, Di; Zhang, Peng; Jiang, Jihong; Zhu, Aihua; Liu, Weijie

2017-11-01

Dye dispersion and the interaction efficiency between azoreductases and dye molecules are rate-limiting steps for the decolorization of azo dyes. In this study, a biosurfactant-producing strain, Pseudomonas taiwanensis L1011, was isolated from crude oil. To increase the yield of the biosurfactant BS-L1011 from P. taiwanensis L1011, culture conditions were optimized including temperature, initial pH, carbon source, nitrogen source and C/N ratio. A maximum yield of 1.12g/L of BS-L1011 was obtained using D-mannitol as carbon source and yeast extract/urea as compound nitrogen source with C/N ratio of 10/4, pH 7.0 and 28°C. BS-L1011 exhibited a low critical micelle concentration (CMC) of 10.5mg/L and was able to reduce the surface tension of water to 25.8±0.1 mN/m. BS-L1011 was stable over a wide range of temperatures, pH values and salt concentrations. The biosurfactant is reported for the first time to accelerate chemical decolorization of Congo red by sodium hypochlorite, and biological decolorization of Amaranth by Bacillus circulans BWL1061, thus showing a potential in the treatment of dyeing wastewater. Copyright © 2017 Elsevier Inc. All rights reserved.

Asymmetrically doped one-dimensional trans-polymers

International Nuclear Information System (INIS)

Caldas, Heron

2009-01-01

More than 30 years ago [H. Shirakawa, E.J. Louis, A.G. MacDiarmid, C.K. Chiang, A.J. Heeger, J. Chem. Soc. Chem. Comm. 578 (1977); S. Etemad, A.J. Heeger, Ann. Rev. Phys. Chem. 33 (1982) 443] it was discovered that doped trans-polyacetylene (CH) x , a one-dimensional (1D) conjugated polymer, exhibits electrical conductivity. In this work we show that an asymmetrically doped 1D trans-polymer has non-conventional properties, as compared to symmetrically doped systems. Depending on the level of asymmetry between the chemical potentials of the two involved fermionic species, the polymer can be in a partially or fully spin polarized state. Some possible experimental consequences of doped 1D trans-polymers used as 1D organic polarized conductors are discussed.

Bioavailability of trans-resveratrol from red wine in humans.

Science.gov (United States)

Vitaglione, Paola; Sforza, Stefano; Galaverna, Gianni; Ghidini, Cristiana; Caporaso, Nicola; Vescovi, Pier Paolo; Fogliano, Vincenzo; Marchelli, Rosangela

2005-05-01

Many in vitro studies demonstrated significant biological effects of trans-resveratrol. Thus, understanding the rate of intestinal absorption and metabolization in vivo of trans-resveratrol is the prerequisite to evaluate its potential health impact. Bioavailability studies mainly in animals or in humans using the pure compound at very high doses were performed. In this work, trans-resveratrol bioavailability from a moderate consumption of red wine in 25 healthy humans has been studied by three different experiments. The wine ingestion was associated to three different dietary approaches: fasting, a standard meal, a meal with high and low amount of lipids. Trans-resveratrol 3- and 4'-glucuronides were synthesized, purified, and characterized as pure standards. Bioavailability data were obtained by measuring the concentration of free, 3-glucuronide and 4'-glucuronide trans-resveratrol by high-performance liquid chromatography (HPLC), both with ultraviolet (UV) and mass spectrometry (MS) detection, in serum samples taken at different times after red wine administration. Free trans-resveratrol was found, in trace amounts, only in some serum samples collected 30 min after red wine ingestion while after longer times resveratrol glucuronides predominated. Trans-resveratrol bioavailability was shown to be independent from the meal or its lipid content. The finding in human serum of trans-resveratrol glucuronides, rather than the free form of the compound, with a high interindividual variability, raises some doubts about the health effects of dietary resveratrol consumption and suggests that the benefits associated to red wine consumption could be probably due to the whole antioxidant pool present in red wine.

Synthesis, electrochemical, spectrophotometric and potentiometric studies of two azo-compounds derived from 4-amino-2-methylquinoline in ethanolic-aqueous buffered solutions

Energy Technology Data Exchange (ETDEWEB)

El-Attar, Mona A.; Ghoneim, Mohamed M. [Analytical Chemistry Research Unit, Chemistry Department, Tanta University (Egypt); Ismail, Iqbal M., E-mail: maema.2011@yahoo.com [Chemistry Department, Faculty of Science, King Abdul Aziz University, Jeddah (Saudi Arabia)

2012-08-15

Two azo-compounds, 2-methyl-4-(5-amino-2-hydroxy-phenylazo)-quinoline (2) and 2-methyl-4-(2-hydroxy-5-nitrophenylazo)-quinoline, derived from 4-amino-2-methylquinoline were synthesized. Their chemical structures were characterized and confirmed by means of elemental chemical analysis, infrared (IR) spectroscopy, {sup 1}H nuclear magnetic resonance (NMR) and mass spectrometry (MS). The electrochemical behavior of the starting compound (4-amino-2-methylquinoline) and of the two synthesized azo-derivatives was studied at the mercury electrode in the B-R universal buffer at various pH values (2-11.5) containing 40% (v/v) ethanol using dc-polarography, cyclic voltammetry and controlled-potential coulometry. Their electrode reaction pathways were elucidated and discussed. The dissociation constants (pKa) of the examined compounds, stability constants and stoichiometry of their complexes in solution with some transition metal ions (Co(II), Ni(II), Cu(II), La(III) and UO{sup 2+}{sub 2}) were determined. (author)

Pressure effect on equilibrium configuration of CTCC-2 spheromak

International Nuclear Information System (INIS)

Nishikawa, M.; Kato, Y.; Satomi, N.; Watanabe, K.

1990-01-01

In CTCC-2 experiment, the initial plasma is produced by a magnetized gun and ejected into a metallic aluminum flux conserver (FC) with thickness of 15 mm. The spheromak is formed in the FC during a life time of 1.5 ms, in which the plasma is isolated from any external feeder. A choking-field-generating coil is equipped on the entrance of the spheroidal FC. The choking field is suppressing some leakage of spheromak field along the entrance duct, which is made of thin stainless steel plate (0.8 mm) for rapid penetration of the choking magnetic field. This resistive part acts as an effective plasma current limiter, which produces stable currentless region (flux hole). The flux hole increases magnetic shear without inserting a central conducting pole along the symmetric axis and is controlled to decrease with the choking field strength. Thus, in CTCC-2 spheromak, a stable oblate spheroidal boundary is rigidly fixed by the metal wall of FC and the entrance hole of FC is effectively closed by choking magnetic field, so that it is suitable to investigate precisely a fine structure of configuration. In spheromak configuration whose aspect ratio is near one, the ratio of the magnetic strength at the inner part to that at the outer part on equi-flux surface (mirror ratio) becomes very large in comparison with that of a large aspect ratio. This extreme configuration with a high mirror ratio may be associated with an anisotropic pressure effect even in collisional state like as our experimental condition. They have investigated the pressure effect on spheromak configuration in more detail. The obtained equilibrium profile is grossly explained by a theoretical profile on assuming low beta limit until now. However, the authors observe a systematic discrepancy between a measured poloidal profile and a theoretical one as mentioned

Comparison of the patient radiation exposure during coronary angiography and angioplasty procedures using trans-radial and trans-femoral access

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Ali Tarighatnia

2016-06-01

Conclusion: On the basis of the results obtained in this study, no differences were found in patients’ radiation dose in both access groups, therefore with regard to comparatively more clinical advantages associated with the Trans-radial access technique it might be a good substitute for Trans-femoral access.

The inverse-trans-influence in tetravalent lanthanide and actinide bis(carbene) complexes

Science.gov (United States)

Gregson, Matthew; Lu, Erli; Mills, David P.; Tuna, Floriana; McInnes, Eric J. L.; Hennig, Christoph; Scheinost, Andreas C.; McMaster, Jonathan; Lewis, William; Blake, Alexander J.; Kerridge, Andrew; Liddle, Stephen T.

2017-02-01

Across the periodic table the trans-influence operates, whereby tightly bonded ligands selectively lengthen mutually trans metal-ligand bonds. Conversely, in high oxidation state actinide complexes the inverse-trans-influence operates, where normally cis strongly donating ligands instead reside trans and actually reinforce each other. However, because the inverse-trans-influence is restricted to high-valent actinyls and a few uranium(V/VI) complexes, it has had limited scope in an area with few unifying rules. Here we report tetravalent cerium, uranium and thorium bis(carbene) complexes with trans C=M=C cores where experimental and theoretical data suggest the presence of an inverse-trans-influence. Studies of hypothetical praseodymium(IV) and terbium(IV) analogues suggest the inverse-trans-influence may extend to these ions but it also diminishes significantly as the 4f orbitals are populated. This work suggests that the inverse-trans-influence may occur beyond high oxidation state 5f metals and hence could encompass mid-range oxidation state actinides and lanthanides. Thus, the inverse-trans-influence might be a more general f-block principle.

High-Energy Electron Confinement in a Magnetic Cusp Configuration

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Jaeyoung Park

2015-06-01

Full Text Available We report experimental results validating the concept that plasma confinement is enhanced in a magnetic cusp configuration when β (plasma pressure/magnetic field pressure is of order unity. This enhancement is required for a fusion power reactor based on cusp confinement to be feasible. The magnetic cusp configuration possesses a critical advantage: the plasma is stable to large scale perturbations. However, early work indicated that plasma loss rates in a reactor based on a cusp configuration were too large for net power production. Grad and others theorized that at high β a sharp boundary would form between the plasma and the magnetic field, leading to substantially smaller loss rates. While not able to confirm the details of Grad’s work, the current experiment does validate, for the first time, the conjecture that confinement is substantially improved at high β. This represents critical progress toward an understanding of the plasma dynamics in a high-β cusp system. We hope that these results will stimulate a renewed interest in the cusp configuration as a fusion confinement candidate. In addition, the enhanced high-energy electron confinement resolves a key impediment to progress of the Polywell fusion concept, which combines a high-β cusp configuration with electrostatic fusion for a compact, power-producing nuclear fusion reactor.

Synthesis of Highly Stable Cobalt Nanomaterial Using Gallic Acid and Its Application in Catalysis

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Saba Naz

2014-01-01

Full Text Available We report the room temperature (25–30°C green synthesis of cobalt nanomaterial (CoNM in an aqueous medium using gallic acid as a reducing and stabilizing agent. pH 9.5 was found to favour the formation of well dispersed flower shaped CoNM. The optimization of various parameters in preparation of nanoscale was studied. The AFM, SEM, EDX, and XRD characterization studies provide detailed information about synthesized CoNM which were of 4–9 nm in dimensions. The highly stable CoNM were used to study their catalytic activity for removal of azo dyes by selecting methyl orange as a model compound. The results revealed that 0.4 mg of CoNM has shown 100% removal of dye from 50 μM aqueous solution of methyl orange. The synthesized CoNM can be easily recovered and recycled several times without decrease in their efficiency.

Removal of anionic azo dyes from aqueous solution by functional ionic liquid cross-linked polymer

International Nuclear Information System (INIS)

Gao, Hejun; Kan, Taotao; Zhao, Siyuan; Qian, Yixia; Cheng, Xiyuan; Wu, Wenli; Wang, Xiaodong; Zheng, Liqiang

2013-01-01

Highlights: • Equilibrium, kinetic and thermodynamic of adsorption of dyes onto PDVB-IL was investigated. • PDVB-IL has a high adsorption capacity to treat dyes solution. • Higher adsorption capacity is due to the functional groups of PDVB-IL. • Molecular structure of dyes influences the adsorption capacity. -- Abstract: A novel functional ionic liquid based cross-linked polymer (PDVB-IL) was synthesized from 1-aminoethyl-3-vinylimidazolium chloride and divinylbenzene for use as an adsorbent. The physicochemical properties of PDVB-IL were investigated by Fourier transform infrared spectroscopy, scanning electron microscopy and thermogravimetric analysis. The adsorptive capacity was investigated using anionic azo dyes of orange II, sunset yellow FCF, and amaranth as adsorbates. The maximum adsorption capacity could reach 925.09, 734.62, and 547.17 mg/g for orange II, sunset yellow FCF and amaranth at 25 °C, respectively, which are much better than most of the other adsorbents reported earlier. The effect of pH value was investigated in the range of 1–8. The result shows that a low pH value is found to favor the adsorption of those anionic azo dyes. The adsorption kinetics and isotherms are well fitted by a pseudo second-order model and Langmuir model, respectively. The adsorption process is found to be dominated by physisorption. The introduction of functional ionic liquid moieties into cross-linked poly(divinylbenzene) polymer constitutes a new and efficient kind of adsorbent

Application of factorial design for the ab initio study of cis- and trans-1,2 dihaloethylene stabilities

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Silva João Bosco P. da

2000-01-01

Full Text Available The chemometric technique Two Level Factorial Design was used to evaluate the principal and interaction effects of wave function modifications on calculated energy differences (DE between the cis and trans isomers of 1,2-dihaloethylenes, C2H2X2 (X=F and Cl. The factorial profile of DE is quite different for these systems. The addition of polarization and diffuse functions to the basis set have the largest effects in describing cis 1,2-difluoroethylene as the most stable isomer. In contrast electronic correlation, at the MP2 level, and the inclusion of polarization functions in the basis set have the largest effects in describing the cis form as the most stable one in the 1,2-dichloroethylenes. In both systems the interaction effects are smaller than the principal effects.

Physics of trans-Planckian gravity

International Nuclear Information System (INIS)

Dvali, Gia; Folkerts, Sarah; Germani, Cristiano

2011-01-01

We study the field theoretical description of a generic theory of gravity flowing to Einstein general relativity in IR. We prove that, if ghost-free, in the weakly-coupled regime such a theory can never become weaker than general relativity. Using this fact, as a by-product, we suggest that in a ghost-free theory of gravity trans-Planckian propagating quantum degrees of freedom cannot exist. The only physical meaning of a trans-Planckian pole is the one of a classical state (black hole) which is described by the light IR quantum degrees of freedom and gives exponentially-suppressed contributions to virtual processes. In this picture Einstein gravity is UV self-complete, although not Wilsonian, and sub-Planckian distances are unobservable in any healthy theory of gravity. We then finally show that this UV/IR correspondence puts a severe constraint on any attempt of conventional Wilsonian UV-completion of trans-Planckian gravity. Specifically, there is no well-defined energy domain in which gravity could become asymptotically weak or safe.

Equilibrium and thermodynamics of azo dyes biosorption onto Spirulina platensis

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G. L. Dotto

2013-03-01

Full Text Available The equilibrium and thermodynamics of azo dye (tartrazine and allura red biosorption onto Spirulina platensis biomass were investigated. The equilibrium curves were obtained at 298, 308, 318 and 328 K, and four isotherm models were fitted the experimental data. Biosorption thermodynamic parameters (ΔG, ΔH and ΔS were estimated. The results showed that the biosorption was favored by a temperature decrease. For both dyes, the Sips model was the best to represent the equilibrium experimental data (R²>0.99 and ARE<5.0% and the maximum biosorption capacities were 363.2 and 468.7 mg g-1 for tartrazine and allura red, respectively, obtained at 298 K. The negative values of ΔG and ΔH showed that the biosorption of both dyes was spontaneous, favorable and exothermic. The positive values of ΔS suggested that the system disorder increases during the biosorption process.

Ruminant and industrial trans-fatty acid uptake in the heart.

Science.gov (United States)

Ganguly, Riya; LaVallee, Renee; Maddaford, Thane G; Devaney, Brittany; Bassett, Chantal M C; Edel, Andrea L; Pierce, Grant N

2016-05-01

Dietary trans-fats are strongly associated with heart disease. However, the capacity for the tissues of the body, and specifically the heart, to take up trans-fats is unknown. It is also unknown if different trans-fats have different uptake capacities in the heart and other tissues of the body. Diets of low-density lipoprotein receptor-deficient mice were supplemented for 14weeks with foods that contained 1.5% of the trans-fat elaidic acid or vaccenic acid. Tissues were extracted and frozen in liquid nitrogen, and then lipids were analyzed by gas chromatography for fatty acid content. Isolated cardiomyocytes were also exposed to elaidic or vaccenic acid in cell culture media for 24h. Dietary supplementation with vaccenic or elaidic acid resulted in a 20-fold higher accumulation of these TFAs in fat deposits in the body in comparison to liver. Liver tissue accumulated about twice as much per gram tissue as heart. Similar quantities of both elaidic acid and vaccenic acid were taken up by the tissues. Isolated cardiomyocytes exhibited an unusually large uptake of trans-fat, and this was dependent upon both the concentration and duration of exposure to the trans-fats but not upon the type of trans-fat. Expression levels of CD36 and FATP4 were not significantly changed during dietary interventions or exposure of cells to trans-fats. We conclude that fat, liver and heart (including cardiomyocytes) are all capable of accumulating trans-fat in response to dietary supplementation without changes in fatty acid transport protein expression. Copyright © 2016 Elsevier Inc. All rights reserved.

Cancer risk assessment of azo dyes and aromatic amines from tattoo bands, folders of paper, toys, bed clothes, watch straps and ink

NARCIS (Netherlands)

Zeilmaker MJ; Kranen HJ van; Veen MP van; Janus J; LBM

2000-01-01

A quantitative assessment was performed to estimate the cancer risk to individuals using tattoo bands, folders of paper, toys, bed clothes, watch straps and ink which are coloured with azo dyes. In these products benzidine and the benzidine related amines o-anisidine, 2,4-toluenediamine,

Tandem Rh-Catalyzed Oxidative C-H Olefination and Cyclization of Enantiomerically Enriched Benzo-1,3-Sulfamidates: Stereoselective Synthesis of trans-1,3-Disubstituted Isoindolines.

Science.gov (United States)

Achary, Raghavendra; Jung, In-A; Lee, Hyeon-Kyu

2018-04-06

A tandem process, involving Rh(III)-catalyzed oxidative C-H olefination of enantiomerically enriched 4-aryl-benzo-1,3-sulfamidates and subsequent intramolecular aza-Michael cyclization has been developed. The reaction produces trans-benzosulfamidate-fused-1,3-disubstituted isoindolines as major products, in which the configurational integrity of the stereogenic center in the starting material is preserved. Further transformations of the benzosulfamidate-fused-1,3-disubstituted isoindolines are described.

Trans-Spatial Utopias

Science.gov (United States)

Kramsch, Claire

2018-01-01

The "trans-" perspectives offered in this special issue are heady stuff. Post-structuralism (philosophy) meets the digital age (electronics), meets globalization (economics), and meets translingual practice (linguistics) to create a perfectly utopian or placeless space for future exploration. I want to first add my voice to the…

Enhancing the electrochemical oxidation of acid-yellow 36 azo dye using boron-doped diamond electrodes by addition of ferrous ion

International Nuclear Information System (INIS)

Villanueva-Rodriguez, M.; Hernandez-Ramirez, A.; Peralta-Hernandez, J.M.; Bandala, Erick R.; Quiroz-Alfaro, Marco A.

2009-01-01

This work shows preliminary results on the electrochemical oxidation process (EOP) using boron-doped diamond (BDD) electrode for acidic yellow 36 oxidation, a common azo dye used in textile industry. The study is centred in the synergetic effect of ferrous ions and hydroxyl free radicals for improving discoloration of azo dye. The assays were carried out in a typical glass cell under potentiostatic conditions. On experimental conditions, the EOP was able to partially remove the dye from the reaction mixture. The reaction rate increased significantly by addition of Fe 2+ (1 mM as ferrous sulphate) to the system and by (assumed) generation of ferrate ion [Fe(VI)] over BDD electrode. Ferrate is considered as a highly oxidizing reagent capable of removing the colorant from the reaction mixture, in synergistic action with the hydroxyl radicals produced on the BDD surface. Further increases in the Fe 2+ concentration lead to depletion of the reaction rate probably due to the hydroxyl radical scavenging effect of Fe 2+ excess in the system.

Magnetization configurations and hysteresis loops of small permalloy ellipses

International Nuclear Information System (INIS)

Schneider, M; Liszkowski, J; Rahm, M; Wegscheider, W; Weiss, D; Hoffmann, H; Zweck, J

2003-01-01

We investigated systematically the easy axis magnetization reversal of 20 nm thick permalloy ellipses with a fixed major axis of 1.47 μm and minor axes of 0.22-1.47 μm. Lorentz transmission electron microscopy was used to image the micromagnetic configurations during magnetization reversal. Hysteresis loops of single ellipses were recorded by means of micro-Hall magnetometry and could be traced back to certain reversal mechanisms observed by Lorentz microscopy. In most cases, the magnetization reversal is initiated by the evolution of a magnetization buckling, followed by the formation of a single, a double, or a trapped vortex configuration. For ellipses with high aspect ratio (length-to-width ratio), the magnetization switches in the reversed magnetic field without creation of a stable vortex configuration. Our experiments show that the characteristic field values for vortex creation, single vortex annihilation, and switching strongly depend on the shape anisotropy of the elements

transPLANT Resources for Triticeae Genomic Data

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Manuel Spannagl

2016-03-01

Full Text Available The genome sequences of many important Triticeae species, including bread wheat ( L. and barley ( L., remained uncharacterized for a long time because their high repeat content, large sizes, and polyploidy. As a result of improvements in sequencing technologies and novel analyses strategies, several of these have recently been deciphered. These efforts have generated new insights into Triticeae biology and genome organization and have important implications for downstream usage by breeders, experimental biologists, and comparative genomicists. transPLANT ( is an EU-funded project aimed at constructing hardware, software, and data infrastructure for genome-scale research in the life sciences. Since the Triticeae data are intrinsically complex, heterogenous, and distributed, the transPLANT consortium has undertaken efforts to develop common data formats and tools that enable the exchange and integration of data from distributed resources. Here we present an overview of the individual Triticeae genome resources hosted by transPLANT partners, introduce the objectives of transPLANT, and outline common developments and interfaces supporting integrated data access.

Dietary trans-fatty acids and metabolic syndrome

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Zdzisław Kochan

2010-12-01

Full Text Available Trans-fatty acids (TFAs, products of partial hydrogenation of vegetable oils, have become more prevalent in our diet since the 1960s, when they replaced animal fats. TFAs also occur naturally in meat and dairy products from ruminants. There is growing evidence that dietary trans-fatty acids may increase the risk of metabolic syndrome. Several studies have demonstrated adverse effects of TFAs on plasma lipids and lipoproteins. In dietary trials, trans-fatty acids have been shown to raise the total cholesterol/HDL cholesterol ratio and Lp(a levels in blood. Moreover, a high intake of TFAs has been associated with an increased risk of coronary heart disease. Prospective cohort studies have shown that dietary trans-fatty acids promote abdominal obesity and weight gain. In addition, it appears that TFA consumption may be associated with the development of insulin resistance and type 2 diabetes. The documented adverse health effects of TFAs emphasise the importance of efforts to reduce the content of partially hydrogenated vegetable oils in foods.

The evolutionary landscape of intergenic trans-splicing events in insects

Science.gov (United States)

Kong, Yimeng; Zhou, Hongxia; Yu, Yao; Chen, Longxian; Hao, Pei; Li, Xuan

2015-01-01

To explore the landscape of intergenic trans-splicing events and characterize their functions and evolutionary dynamics, we conduct a mega-data study of a phylogeny containing eight species across five orders of class Insecta, a model system spanning 400 million years of evolution. A total of 1,627 trans-splicing events involving 2,199 genes are identified, accounting for 1.58% of the total genes. Homology analysis reveals that mod(mdg4)-like trans-splicing is the only conserved event that is consistently observed in multiple species across two orders, which represents a unique case of functional diversification involving trans-splicing. Thus, evolutionarily its potential for generating proteins with novel function is not broadly utilized by insects. Furthermore, 146 non-mod trans-spliced transcripts are found to resemble canonical genes from different species. Trans-splicing preserving the function of ‘breakup' genes may serve as a general mechanism for relaxing the constraints on gene structure, with profound implications for the evolution of genes and genomes. PMID:26521696

READING COLONIZATION IN CONRAD'S TRANS-RACIAL LOVE PLOTS

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Sandra Lilyana

2017-07-01

Full Text Available The study is about a close look at Conrad's trans-racial romance related to the Victorian period. Trans-racial love between white men and non-white women becomes a popular theme in the early works of Josep Conrad, a famous writer of the late Victorian period. Using a closely technical reading in the three of Conrad's works Lord Jim, Almayer's Folly, and An Outcast of the Island, we can show that such a trans-racial romance is not merely meant for appreciating equivalence. In turn, the trans-racial romance of Conrad's can be understood as the reflection of the Western colonization on the East where the white men take a role as subjects who had dominately explored while the non-white women as objects who are passively being explored. Key words: colonization, race, romance plot, subject, object, and dominance

Technical aspects of trans reduction in margarines

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Van Duijn Gerrit

2000-01-01

Full Text Available The opinion of nutritional science on the effect of trans fatty acids on blood cholesterol has drastically changed during the last decade. As a reaction to these new findings, the European margarine industry decided in the mid nineties to eliminate trans containing components from their margarine fat phase compositions. This excluded practically the use of partially hydrogenated oils and fats. Trans-free margarines have been introduced with optimised fat crystal structures stabilising a maximum of water in oil emulsion with a minimum of solid fat phase. These fat crystal structures are formed by fat phase components obtained from interesterification and/or fractionation of non-hydrogenated and/or fully hydrogenated feedstocks.

Trans- and cis-2-phenylindole platinum(II) complexes as cytotoxic agents against human breast adenocarcinoma cell lines

Science.gov (United States)

Tomé, Maria; López, Concepción; González, Asensio; Ozay, Bahadir; Quirante, Josefina; Font-Bardía, Mercè; Calvet, Teresa; Calvis, Carme; Messeguer, Ramon; Baldomá, Laura; Badía, Josefa

2013-09-01

The synthesis and characterization of the new 2-phenylindole derivative: C8H3N-2-C6H5-3NOMe-5OMe (3c) and the trans- and cis-isomers of [Pt(3c)Cl2(DMSO)] complexes (4c and 5c, respectively) are described. The crystal structures of 4c·CH2Cl2 and 5c confirm: (a) the existence of a Pt-Nindole bond, (b) the relative arrangement of the Cl- ligands [trans- (in 4c) or cis- (in 5c)] and (c) the anti-(E) configuration of the oxime. The cytotoxic assessment of C8H3N-2-(C6H4-4‧R1)-3NOMe-5R2 [with R1 = R2 = H (3a); R1 = Cl, R2 = H (3b) and R1 = H, R2 = OMe (3c)] and the geometrical isomers of [Pt(L)Cl2(DMSO)] with L = 3a-3c [trans- (4a-4c) and cis- (5a-5c), respectively] against human breast adenocarcinoma cell lines (MDA-MB231 and MCF-7) is also reported and reveals that all the platinum(II) complexes (except 4a) are more cytotoxic than cisplatin in front of the MCF7 cell line. Electrophoretic DNA migration studies of the synthesized compounds in the absence and in the presence of topoisomerase-I have been performed, in order to get further insights into their mechanism of action.

Vibrational quasi-degenerate perturbation theory with optimized coordinates: applications to ethylene and trans-1,3-butadiene.

Science.gov (United States)

Yagi, Kiyoshi; Otaki, Hiroki

2014-02-28

A perturbative extension to optimized coordinate vibrational self-consistent field (oc-VSCF) is proposed based on the quasi-degenerate perturbation theory (QDPT). A scheme to construct the degenerate space (P space) is developed, which incorporates degenerate configurations and alleviates the divergence of perturbative expansion due to localized coordinates in oc-VSCF (e.g., local O-H stretching modes of water). An efficient configuration selection scheme is also implemented, which screens out the Hamiltonian matrix element between the P space configuration (p) and the complementary Q space configuration (q) based on a difference in their quantum numbers (λpq = ∑s|ps - qs|). It is demonstrated that the second-order vibrational QDPT based on optimized coordinates (oc-VQDPT2) smoothly converges with respect to the order of the mode coupling, and outperforms the conventional one based on normal coordinates. Furthermore, an improved, fast algorithm is developed for optimizing the coordinates. First, the minimization of the VSCF energy is conducted in a restricted parameter space, in which only a portion of pairs of coordinates is selectively transformed. A rational index is devised for this purpose, which identifies the important coordinate pairs to mix from others that may remain unchanged based on the magnitude of harmonic coupling induced by the transformation. Second, a cubic force field (CFF) is employed in place of a quartic force field, which bypasses intensive procedures that arise due to the presence of the fourth-order force constants. It is found that oc-VSCF based on CFF together with the pair selection scheme yields the coordinates similar in character to the conventional ones such that the final vibrational energy is affected very little while gaining an order of magnitude acceleration. The proposed method is applied to ethylene and trans-1,3-butadiene. An accurate, multi-resolution potential, which combines the MP2 and coupled-cluster with singles

Vibrational quasi-degenerate perturbation theory with optimized coordinates: Applications to ethylene and trans-1,3-butadiene

Energy Technology Data Exchange (ETDEWEB)

Yagi, Kiyoshi, E-mail: kiyoshi.yagi@riken.jp; Otaki, Hiroki [Theoretical Molecular Science Laboratory, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan)

2014-02-28

A perturbative extension to optimized coordinate vibrational self-consistent field (oc-VSCF) is proposed based on the quasi-degenerate perturbation theory (QDPT). A scheme to construct the degenerate space (P space) is developed, which incorporates degenerate configurations and alleviates the divergence of perturbative expansion due to localized coordinates in oc-VSCF (e.g., local O–H stretching modes of water). An efficient configuration selection scheme is also implemented, which screens out the Hamiltonian matrix element between the P space configuration (p) and the complementary Q space configuration (q) based on a difference in their quantum numbers (λ{sub pq} = ∑{sub s}|p{sub s} − q{sub s}|). It is demonstrated that the second-order vibrational QDPT based on optimized coordinates (oc-VQDPT2) smoothly converges with respect to the order of the mode coupling, and outperforms the conventional one based on normal coordinates. Furthermore, an improved, fast algorithm is developed for optimizing the coordinates. First, the minimization of the VSCF energy is conducted in a restricted parameter space, in which only a portion of pairs of coordinates is selectively transformed. A rational index is devised for this purpose, which identifies the important coordinate pairs to mix from others that may remain unchanged based on the magnitude of harmonic coupling induced by the transformation. Second, a cubic force field (CFF) is employed in place of a quartic force field, which bypasses intensive procedures that arise due to the presence of the fourth-order force constants. It is found that oc-VSCF based on CFF together with the pair selection scheme yields the coordinates similar in character to the conventional ones such that the final vibrational energy is affected very little while gaining an order of magnitude acceleration. The proposed method is applied to ethylene and trans-1,3-butadiene. An accurate, multi-resolution potential, which combines the MP2 and

Unscripting Curriculum: Toward a Critical Trans Pedagogy

Science.gov (United States)

Keenan, Harper Benjamin

2017-01-01

In this essay, Harper B. Keenan draws on his own experience as a white queer and trans educator to consider the meaning of a critical trans pedagogy. Amid dissonant narratives of equal rights and subjection, he explores how his classroom teaching is shaped by his own experience of gender conditioning as well as by the contemporary political…

Structural modification of trans-cinnamic acid using Colletotrichum acutatum

OpenAIRE

Velasco B., Rodrigo; Gil G., Jesús H.; García P., Carlos M.; Durango R., Diego L.

2012-01-01

The biotransformation of trans-cinnamic acid by whole cells of the Colombian native phytopathogenic fungus Colletotrichum acutatum was studied. Initially, fungitoxicity of this compound against C. acutatum was evaluated; trans-cinnamic acid exhibited a moderate to weak toxicity against the microorganism and apparently a detoxification mechanism was present. Then, in order to study such mechanism and explore the capacity of this fungus to biotransform trans-cinnamic acid into value-added produ...

Development and validation of a HPLC method for the determination of trans-resveratrol in spiked human plasma

Directory of Open Access Journals (Sweden)

Gurinder Singh

2012-01-01

Full Text Available A simple, accurate, precise, sensitive, and reproducible high-performance liquid chromatography method was developed for the determination of Resveratrol (trans-3, 4΄,5-trihydroxystilbene in human plasma using liquid-liquid extraction. Caffeine was employed as an internal standard (IS. However, little information is known about its distribution in the organism generally because of the lack of accurate and precise detection methods. The chromatographic separation was achieved on a Phenomenex C18 column (250 mm × 4.6 mm, 5 μm at room temperature in isocratic mode, and the column effluent was monitored by UV detector at 306 nm. The mobile phase used was methanol: phosphate buffer (pH 6.8 adjusted with 0.5% (v/v orthophosphoric acid solution in Milli-Q water (63:37%, v/v at a flow rate of 1.0 ml/min. Nominal retention times of trans-resveratrol and IS were 3.94 and 7.86 minutes, respectively. Limits of detection and Limits of quantification of trans-resveratrol were 0.006 μg/ml and 0.008 μg/ml, respectively. This method was linear over the range of 0.010 to 6.4 μg/ml with regression coefficient greater than 0.9998. The inter- and intra-day precisions in the samples, 0.010, 3.2 and 6.4 μg/ml of trans-resveratrol was in the range 0.63 to 2.12% relative standard deviation (RSD and 0.46 to 1.02% RSD, respectively. Resveratrol was found to be stable for a period of 15 days on storage at -20°C. The method was found to be precise, accurate, and specific during the study.

Effect of atomic layer deposited Al2O3:ZnO alloys on thin-film silicon photovoltaic devices

Science.gov (United States)

Abdul Hadi, Sabina; Dushaq, Ghada; Nayfeh, Ammar

2017-12-01

In this work, we present the effects of the Al2O3:ZnO ratio on the optical and electrical properties of aluminum doped ZnO (AZO) layers deposited by atomic layer deposition, along with AZO application as the anti-reflective coating (ARC) layer and in heterojunction configurations. Here, we report complex refractive indices for AZO layers with different numbers of aluminum atomic cycles (ZnO:Al2O3 = 1:0, 39:1, 19:1, and 9:1) and we confirm their validity by fitting models to experimental data. Furthermore, the most conductive layer (ZnO:Al2O3 = 19:1, conductivity ˜4.6 mΩ cm) is used to fabricate AZO/n+/p-Si thin film solar cells and AZO/p-Si heterojunction devices. The impact of the AZO layer on the photovoltaic properties of these devices is studied by different characterization techniques, resulting in the extraction of recombination and energy band parameters related to the AZO layer. Our results confirm that AZO 19:1 can be used as a low cost and effective conductive ARC layer for solar cells. However, AZO/p-Si heterojunctions suffer from an insufficient depletion region width (˜100 nm) and recombination at the interface states, with an estimated potential barrier of ˜0.6-0.62 eV. The work function of AZO (ZnO:Al2O3 = 19:1) is estimated to be in the range between 4.36 and 4.57 eV. These material properties limit the use of AZO as an emitter in Si solar cells. However, the results imply that AZO based heterojunctions could have applications as low-cost photodetectors or photodiodes, operating under relatively low reverse bias.

TransPlanckian Particles and the Quantization of Time

NARCIS (Netherlands)

Hooft, G. 't

1999-01-01

Trans-Planckian particles are elementary particles accelerated such that their energies surpass the Planck value. There are several reasons to believe that trans-Planckian particles do not represent independent degrees of freedom in Hilbert space, but they are controlled by the cis-Planckian

Low Trans Hydrogenation

Science.gov (United States)

Although hydrogenation has been the technology of choice for fat formulation for many years recent concerns over the health and nutrition of trans fatty acids have had a profound effect on the edible oil industry. Since Jan. 1, 2006, TFA has been required on nutrition labels along with saturated an...

Synthesis, Characterisation and DFT Calculations of Azo-Imine Dyes

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Sevil Özkınalı

2017-11-01

Full Text Available In this study, azo dyes containing an imine group were synthesised by coupling p-hydroxybenzylidene aniline with the diazonium salts of p-toluidine, 4-aminophenol, aniline, p-chloroaniline, p-fluoroaniline, and p-nitroaniline. The compounds were characterised by melting point, elemental, UV-Vis and IR analyses as well as 1H-NMR and 13C-NMR spectroscopies. Moreover, the experimental data were supplemented with density functional theory (DFT calculations. The experimental data on FT-IR and UV–Vis spectra of the compounds were compared with theoretical results. The DFT calculations were performed to obtain the ground state geometries of the compounds using the B3LYP hybrid functional level with 6-311++g(2d,2p basis set. Frontier molecular orbital energies, band gap energies and some chemical reactivity parameters, such as chemical hardness and electronegativity, were calculated and compared with experimental values. A significant correlation was observed between the dipole moment and polarities of the solvents and the absorption wavelength of the compounds.

Evaluation of the Impact of Ruminant Trans Fatty Acids on Human Health: Important Aspects to Consider.

Science.gov (United States)

Kuhnt, Katrin; Degen, Christian; Jahreis, Gerhard

2016-09-09

The definition and evaluation of trans fatty acids (TFA) with regard to foodstuffs and health hazard are not consistent. Based on the current situation, the term should be restricted only to TFA with isolated double bonds in trans-configuration. Conjugated linoleic acids (CLA) should be separately assessed. Ideally, the origin of the consumed fat should be declared, i.e., ruminant TFA (R-TFA) and industrial TFA (non-ruminant; I-TFA). In ruminant fat, more than 50% of R-TFA consists of vaccenic acid (C18:1 t11). In addition, natural CLA, i.e., c9,t11 CLA is also present. Both are elevated in products from organic farming. In contrast to elaidic acid (t9) and t10, which occur mainly in partially hydrogenated industrial fat, t11 is partially metabolized into c9,t11 CLA via Δ9-desaturation. This is the major metabolic criterion used to differentiate between t11 and other trans C18:1. t11 indicates health beneficial effects in several studies. Moreover, CLA in milk fat is associated with the prevention of allergy and asthma. An analysis of the few studies relating to R-TFA alone makes clear that no convincing adverse physiological effect can be attributed to R-TFA. Only extremely high R-TFA intakes cause negative change in blood lipids. In conclusion, in most European countries, the intake of R-TFA is assessed as being low to moderate. Restriction of R-TFA would unjustifiably represent a disadvantage for organic farming of milk.

Decolourisations and biodegradations of model azo dye solutions using a sequence batch reactor, followed by ultrafiltration

DEFF Research Database (Denmark)

Korenak, J.; Ploder, J.; Trček, J.

2018-01-01

RNA gene and ITS1-5.8S rDNA-ITS2 sequence analysis, respectively. Serratia marcescens and Klebsiella oxytoca were the most common bacteria with the highest number present during the aerobic and anaerobic phases of the bioprocess. In addition, a high number of Elizabethkingia miricola, Morganella morganii......, Comamonas testosteroni, Trichosporon sp. and Galactomyces sp. were detected. Taken together, our results demonstrated that the sequencing batch reactor system combined with ultrafiltration is an efficient technique for treatment of wastewater containing azo dye. Moreover, the ultrafiltration effectively...

Perfil nutricional de alimentos com alegação de zero gordura trans Nutritional profile of foods with zero trans fatty acids claim

Directory of Open Access Journals (Sweden)

Ana Carolina Moron Gagliardi

2009-01-01

Full Text Available OBJETIVO: Avaliar a composição de ácidos graxos de alguns alimentos industrializados disponíveis no mercado brasileiro nos quais houve redução da quantidade de ácidos graxos trans. Verificar também se estes alimentos atendem às quantidades recomendadas de consumo de gordura saturada, após redução de gordura trans. MÉTODOS: Alimentos industrializados (margarina cremosa A e B, margarina com fitosterol, biscoito doce recheado, biscoito salgado sem recheio, batata frita e lanche com hambúrguer de fast food multinacional com alegação de 0% de gordura trans foram adquiridos em pontos comerciais e analisados em cromatógrafo gasoso. RESULTADOS: Apesar da redução nas quantidades de ácidos graxos trans, os alimentos analisados contêm grandes quantidades de gorduras saturadas principalmente o ácido palmítico. Além disso, alguns dos alimentos estudados apresentam uma razão n-3/n-6 fora do recomendado para a prevenção da aterosclerose. CONCLUSÃO: O consumo irrestrito desses alimentos tem forte potencial deletério para a saúde. O rótulo de ausência de ácidos graxos trans deve ser visto com cuidado e não significa uma liberação para o consumo irrestrito desses alimentos.OBJECTIVE: To evaluate the composition of fatty acids in some foods available in the Brazilian market in which there was a claimed reduction in the amount of trans fatty acids. Also evaluate whether these foods meet recommended amounts for saturated fat consumption, after reduction of trans fat amounts. METHODS: Industrialized food (creamy margarine A and B, plant sterol margarine, stuffed sweet biscuit, salty biscuit without stuffing, French fried potatoes and a burger lunch from a multinational chain of "fast food" all with the allegation of 0% trans fat content were purchased in commercial points and analyzed by gas chromatography. RESULTS: Despite the reduction in trans fatty acid amounts, analyzed foods contained large concentrations of saturated fats

CYP-450 isoenzymes catalyze the generation of hazardous aromatic amines after reaction with the azo dye Sudan III.

Science.gov (United States)

Zanoni, Thalita Boldrin; Lizier, Thiago M; Assis, Marilda das Dores; Zanoni, Maria Valnice B; de Oliveira, Danielle Palma

2013-07-01

This work describes the mutagenic response of Sudan III, an adulterant food dye, using Salmonella typhimurium assay and the generation of hazardous aromatic amines after different oxidation methods of this azo dye. For that, we used metabolic activation by S9, catalytic oxidation by ironporphyrin and electrochemistry oxidation in order to simulate endogenous oxidation conditions. The oxidation reactions promoted discoloration from 65% to 95% of Sudan III at 1 × 10(-4)molL(-1) and generation of 7.6 × 10(-7)molL(-1) to 0.31 × 10(-4)molL(-1) of aniline, o-anisidine, 2-methoxi-5-methylaniline, 4-aminobiphenyl, 4,4'-oxydianiline; 4,4'-diaminodiphenylmethane and 2,6-dimethylaniline. The results were confirmed by LC-MS-MS experiments. We also correlate the mutagenic effects of Sudan III using S. typhimurium with the strain TA1535 in the presence of exogenous metabolic activation (S9) with the metabolization products of this compound. Our findings clearly indicate that aromatic amines are formed due to oxidative reactions that can be promoted by hepatic cells, after the ingestion of Sudan III. Considering that, the use of azo compounds as food dyestuffs should be carefully controlled. Copyright © 2013 Elsevier Ltd. All rights reserved.

cis- and trans-2,3,3a,4,5,9b-Hexahydro-1H-benz[e]indoles: synthesis and evaluation of dopamine D2, and D3 receptor binding affinity

DEFF Research Database (Denmark)

Song, Xiaodong; Crider, Michael A.; Cruse, Sharon F.

1999-01-01

cis- and trans-2,3,3a,4,5,9b-hexahydro-1H-benz [e]indoles were synthesized as conformationally rigid analogues of 3-phenylpyrrolidine and evaluated for dopamine (DA) D2S and D3 receptor binding affinity. The tricyclic benz[e]indole nucleus was constructed by a previously reported reductive...... configuration. These novel ligands may be useful tools for gaining additional information about the DA D3 receptor. Copyright Elsevier, Paris.dopamine / D2S receptor / D3 receptor / cis- and trans-2,3,3a,4,5,9b-hexahydro-1H-benz[e]indoles / receptor binding affinity....... receptors was shown by compounds substituted with N-n-propyl or N-allyl groups. The cis-(+-)-N-allyl derivative 21e demonstrated a D2S/D3 selectivity of 290. Resolution of cis-(+-)-5 and trans-(+-)- 21c into individual enantiomers showed that in both series the more active isomer had 3aR absolute...

DMol3/COSMO-RS prediction of aqueous solubility and reactivity of selected Azo dyes: Effect of global orbital cut-off and COSMO segment variation

CSIR Research Space (South Africa)

Wahab, OO

2018-01-01

Full Text Available Aqueous solubility and reactivity of four azo dyes were investigated by DMol3/COSMO-RS calculation to examine the effects of global orbital cut-off and COSMO segment variation on the accuracies of theoretical solubility and reactivity. The studied...

Degradation of a mono sulfonated azo dye by an integrated bio sorption and anaerobic system

International Nuclear Information System (INIS)

Goncalves, L. C.; Campos, R.; Pinheiro, H. M.; Lopes, A.; Ferra, M. I.

2009-01-01

A simulated textile effluent containing a mono sulphonated azo dye was fed to an anaerobic bioreactor in which a natural adsorbent, spent brewery grains (SBG), was incorporated. SABG is a by-product of the brewing industry and could act as adsorbent as well an electron shuttle (lignin fraction) in the dye degradation mechanism. Furthermore, it can also work as a conditioner for the anaerobic biomass. The influence of the dye (Acid Orange 7, AO7) concentration (60 and 150 mg/L) and the presence of SBG in the performance of upflow anaerobic sludge blanket reactor (UASB) was evaluated. (Author)

Degradation of a mono sulfonated azo dye by an integrated bio sorption and anaerobic system

Energy Technology Data Exchange (ETDEWEB)

Goncalves, L. C.; Campos, R.; Pinheiro, H. M.; Lopes, A.; Ferra, M. I.

2009-07-01

A simulated textile effluent containing a mono sulphonated azo dye was fed to an anaerobic bioreactor in which a natural adsorbent, spent brewery grains (SBG), was incorporated. SABG is a by-product of the brewing industry and could act as adsorbent as well an electron shuttle (lignin fraction) in the dye degradation mechanism. Furthermore, it can also work as a conditioner for the anaerobic biomass. The influence of the dye (Acid Orange 7, AO7) concentration (60 and 150 mg/L) and the presence of SBG in the performance of upflow anaerobic sludge blanket reactor (UASB) was evaluated. (Author)

Synthesis of a new class of aminocyclitol analogues with the conduramine D-2 configuration

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Latif Kelebekli

2010-02-01

Full Text Available A new class of aminocyclitol derivatives with the bicyclo[4.2.0]octane skeleton was synthesized starting from cyclooctatetraene. Photooxygenation of trans-7,8-diacetoxy- and cis-7,8-dichlorobicyclo[4.2.0]octa-2,4-diene afforded the bicyclic endoperoxides. Reduction of the latter with thiourea followed by a Pd(0 catalyzed ionization/cyclization reaction gave the corresponding oxazolidinone derivatives. Oxidation of the double bond with KMnO4 or OsO4 followed by acetylation gave the acetate derivatives, the exact configuration of which was determined by spectroscopic methods. Hydrolysis of the oxazolidinone rings and removal of the acetate groups furnished the desired aminocyclitols.

Waste Plant Material as a Potential Adsorbent of a Selected Azo Dye

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Tomczak Elwira

2017-06-01

Full Text Available This paper discusses the adsorption of Direct Orange 26 azo dye on sunflower husk - an agricultural waste product. During the study, sorption kinetics and equilibrium as well as sorption capacity of the husk were investigated. The adsorption kinetics was analyzed using pseudo-first and pseudo-second order equations, which indicated a chemical sorption mechanism. The sorption equilibrium was approximated with the two-parameter Freundlich and Langmuir equations and the three-parameter Redlich-Peterson equation. The main experiments were carried out in a laboratory adsorption column under different process conditions. Experimental data were interpreted with the Thomas model, based on the volumetric flow rate, initial composition of the feed solution and mass of the adsorbent. The results of modeling the adsorption equilibrium, adsorption kinetics and adsorption dynamics were evaluated statistically.

Assessment of X-point target divertor configuration for power handling and detachment front control

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M.V. Umansky

2017-08-01

Full Text Available A study of long-legged tokamak divertor configurations is performed with the edge transport code UEDGE (Rognlien et al., J. Nucl. Mater. 196, 347, 1992. The model parameters are based on the ADX tokamak concept design (LaBombard et al., Nucl. Fusion 55, 053020, 2015. Several long-legged divertor configurations are considered, in particular the X-point target configuration proposed for ADX, and compared with a standard divertor. For otherwise identical conditions, a scan of the input power from the core plasma is performed. It is found that as the power is reduced to a threshold value, the plasma in the outer leg transitions to a fully detached state which defines the upper limit on the power for detached divertor operation. Reducing the power further results in the detachment front shifting upstream but remaining stable. At low power the detachment front eventually moves to the primary X-point, which is usually associated with degradation of the core plasma, and this defines the lower limit on the power for the detached divertor operation. For the studied parameters, the operation window for a detached divertor in the standard divertor configuration is very small, or even non-existent; under the same conditions for long-legged divertors the detached operation window is quite large, in particular for the X-point target configuration, allowing a factor of 5–10 variation in the input power. These modeling results point to possibility of stable fully detached divertor operation for a tokamak with extended divertor legs.

Design of Trypanosoma rangeli sialidase mutants with improved trans-sialidase activity.

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Christian Nyffenegger

Full Text Available A sialidase (EC 3.2.1.18 from the non-pathogenic Trypanosoma rangeli, TrSA, has been shown to exert trans-sialidase activity after mutation of five specific amino acids in the active site (M96V, A98P, S120Y, G249Y, Q284P to form the so-called TrSA5mut enzyme. By computational and hypothesis driven approaches additional mutations enhancing the trans-sialidase activity have been suggested. In the present work, we made a systematic combination of these mutations leading to seven new variants of the T. rangeli sialidase, having 6-16 targeted amino acid mutations. The resulting enzyme variants were analyzed via kinetics for their ability to carry out trans-sialidase reaction using CGMP and D-lactose as substrates. The sialidase variants with 15 and 16 mutations, respectively, exhibited significantly improved trans-sialidase activity for D-lactose sialylation. Our results corroborate, that computational studies of trans-glycosylation can be a valuable input in the design of novel trans-glycosidases, but also highlight the importance of experimental validation in order to assess the performance. In conclusion, two of the seven mutants displayed a dramatic switch in specificity from hydrolysis towards trans-sialylation and constitute the most potent trans-sialidase mutants of TrSA described in literature to date.

Interesterificação química: alternativa para obtenção de gorduras zero trans Chemical interresterification: alternative to production of zero trans fats

Directory of Open Access Journals (Sweden)

Ana Paula Badan Ribeiro

2007-10-01

Full Text Available The function of lipids in human nutrition has been intensively debated in the last decade.This context reinforces the concern about controlling the trans fat ingestion, due to its negative implications on health. Interesterification provides an important alternative to modify the consistency of oils and fats without causing formation of trans isomers. This article reports research done towards production of zero trans fats by chemical interesterification, for different industrial purposes. Aspects related to the effect of trans fats on diet, their impact on health and modifications in Brazilian legislation are also covered.

Trans-dinitroglycoluril isomers-A DFT treatment

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Lemi Türker

2017-02-01

Full Text Available Isomers of trans-1,4-Dinitroglycoluril (trans-DINGU and their 1,3-tautomers are considered within the constraints of B3LYP/6-31++G (d,p and B3LYP/CC-PVTZ levels of DFT calculations. Additionally, the interactions of these isomers and proton in vacuum are investigated. The data have revealed that two of the three isomers undergo CH bond cleavage as the result of interaction with proton in vacuum. The total energies, some structural properties, the calculated IR and UV spectra are discussed.

A simplified study of trans-mitral Doppler patterns

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Thomas George

2008-11-01

Full Text Available Abstract Background Trans-mitral Doppler produces complex patterns with a great deal of variability. There are several confusing numerical measures and indices to study these patterns. However trans-mitral Doppler produces readymade data visualization by pattern generation which could be interpreted by pattern analysis. By following a systematic approach we could create an order and use this tool to study cardiac function. Presentation of the hypothesis In this new approach we eliminate the variables and apply pattern recognition as the main criterion of study. Proper terminologies are also devised to avoid confusion. In this way we can get some meaningful information. Testing the hypothesis Trans-mitral Doppler should be seen as patterns rather than the amplitude. The hypothesis can be proven by logical deduction, extrapolation and elimination of variables. Trans-mitral flow is also analyzed vis-à-vis the Starling's Law applied to the left atrium. Implications of the hypothesis Trans-mitral Doppler patterns are not just useful for evaluating diastolic function. They are also useful to evaluate systolic function. By following this schema we could get useful diagnostic information and therapeutic options using simple pattern recognition with minimal measurements. This simplified but practical approach will be useful in day to day clinical practice and help in understanding cardiac function better. This will also standardize research and improve communication.

Synthesis and antibacterial activity of novel Pyrazolo [3, 4-B] quinoline based heterocyclic azo compounds and their dyeing performance

International Nuclear Information System (INIS)

Thaokar, Sanjay F.; Patel, Dinesh M.; Patel, Manish P.; Patel, Ranjan G.

2007-01-01

3-Amino-6-methyl-1H- pyrazolo [3, 4-B] quinoline was synthesized in good yield. Monoazo compounds were prepared using this intermediate as diazo component with various heterocyclic coupling components. All the azo compounds were characterized by their percentage yield, melting point, elemental analysis, UV-visible spectra, IR-spectra and dyeing performance on nylon and polyester fibres and by their antibacterial activity against gram positive and gram negative bacteria. (author)

Trans-sphenoidal excision of craniopharyngiomas.

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Nagpal R

1991-04-01

Full Text Available Craniopharyngiomas have been by and large excised by the transcranial route. Since 1982, 11 patients have been operated by the traus-sphensidal route in the department. The clinical features with which they were presented, diagnostic investigations, details of surgical procedures and follow-up analysis is being presented here. A retrospective study of radiological investigation was done to determine the features that help decide the choice of surgical approach to these lesions. Only lesions that were primarily intrasellar, cystic and those that expanded the sella could be treated by the trans-sphenoidal route. Associated suprasellar extensions could also be removed. Predominantly calcified or firm, fleshy tumours lent themselves poorly to removal by the trans-sphenoidal route.

TransAlta Corporation 1996 annual report : new directions, new opportunities

International Nuclear Information System (INIS)

Anon.

1997-01-01

TransAlta Corp. is an energy management company that operates through two subsidiaries: (1) TransAlta Utilities Corp. which owns and operates electricity generation, transmission and distribution assets in Alberta, and (2) TransAlta Energy Corp. which is in the business of electric and thermal energy supply, gas and electricity distribution, energy services and energy marketing in regions of Canada, New Zealand, Australia, Argentina and the United States. This report presents a summary of operations, and provides consolidated financial statements and common share information for 1996. During the year the corporation advanced three significant initiatives (1) operational effectiveness, as shown by impressive productivity increases, and major investments in three independent power projects, (2) improved strategic direction through a review of plans and options, resulting in a clearer, more focused vision of the future, and (3) realignment of the organizational structure by centralizing marketing and sales functions, and establishing a corporate business development group. Details of operational and financial results were provided for both subsidiaries, i. e. TransAlta Utilities and TransAlta Energy. Sales of electric energy for TransAlta Utilities amounted to 27.8 billion kWh; 4.6 billion kWh for TransAlta Energy. Return on equity was 11.4 per cent, down from 11.8 per cent in 1995. Net earnings per common share were $1.14 per share (including one-time items), the same as in 1995. tabs., figs

Biscoitos recheados: quanto mais baratos maior teor de gordura trans? = Filled cookies: the cheaper the higher trans fat content?

Directory of Open Access Journals (Sweden)

Galdino, Tatiana Pizzato

2010-01-01

Conclusões: quanto maior a quantidade de gorduras trans, menor a quantidade de gordura saturada e menor preço. Sugere-se uma revisão na legislação quanto à inserção da quantidade exata de gorduras trans no rótulo, uma vez que o consumo elevado dessas gorduras está associado a dislipidemias, um fator de risco para doença cardiovascular

Novel acid mono azo dye compound: Synthesis, characterization, vibrational, optical and theoretical investigations of 2-[(E)-(8-hydroxyquinolin-5-yl)-diazenyl]-4,5-dimethoxybenzoic acid

Science.gov (United States)

Saçmacı, Mustafa; Çavuş, Hatice Kanbur; Arı, Hatice; Şahingöz, Recep; Özpozan, Talat

2012-11-01

Novel acid mono azo dye, 2-[(E)-(8-hydroxyquinolin-5yl)-diazenyl]-4,5-dimethoxybenzoic acid (HQD), was synthesized by coupling diazonium salt solution of 2-amino-4,5-dimethoxybenzoic acid (DMA) with 8-hydroxyquinoline (HQ). This dye was characterized by UV-vis, IR & Raman, 1H and 13C NMR spectroscopic techniques and elemental analysis. The normal coordinate analysis of HQD was also performed to assign each band in vibrational spectra. DFT (B3LYP and B3PW91) calculations were employed to optimize the geometry, to interpret NMR spectra, to calculate and to determine the stable tautomeric structure of the compound. Natural Bond Orbital (NBO) analysis was performed to investigate intramolecular interactions. The vibrational spectral data obtained from solid phase IR & Raman spectra were assigned based on the results of the theoretical calculations. UV-vis spectroscopic technique was employed to obtain the optical band gap of HQD. The analysis of the optical absorption data revealed the existence of direct and indirect transitions in the optical band gaps. The optical band gaps of HQD have been found 1.95 and 1.90 eV for direct and indirect transitions, respectively.

Multi-Stable Conductance States in Metallic Double-Walled Carbon Nanotubes

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Ci Lijie

2009-01-01

Full Text Available Abstract Electrical transport properties of individual metallic double-walled carbon nanotubes (DWCNTs were measured down to liquid helium temperature, and multi-stable conductance states were found in DWCNTs. At a certain temperature, DWCNTs can switch continuously between two or more electronic states, but below certain temperature, DWCNTs are stable only at one of them. The temperature for switching is always different from tube to tube, and even different from thermal cycle to cycle for the same tube. In addition to thermal activation, gate voltage scanning can also realize such switching among different electronic states. The multi-stable conductance states in metallic DWCNTs can be attributed to different Fermi level or occasional scattering centers induced by different configurations between their inner and outer tubes.

Mapping Discrimination Experienced by Indonesian Trans* FtM Persons.

Science.gov (United States)

Gordon, Danny; Pratama, Mario Prajna

2017-01-01

This work sought to document how Indonesian trans* FtM persons experienced discrimination across the interlinked domains of social networks, religious and educational institutions, employment and the workplace, and health care institutions. Objectives were (1) to map the discrimination experienced by trans* FtM individuals in Indonesia, and (2) to establish the specific priorities of the Indonesian trans* FtM community. In-depth interviews, focus groups, and participant observation was used involving 14 respondents. Findings revealed that respondents experienced othering through rejection, misidentification, harassment, "correction," and bureaucratic discrimination across the five preestablished domains. Health care and a lack of information emerged as areas of particular concern for respondents. This work calls for health care that is sensitive to the needs of trans* FtM people coupled with high-quality information to alleviate the cycles through which discrimination is sustained.

Evolution of cichlid vision via trans-regulatory divergence

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O’Quin Kelly E

2012-12-01

Full Text Available Abstract Background Phenotypic evolution may occur through mutations that affect either the structure or expression of protein-coding genes. Although the evolution of color vision has historically been attributed to structural mutations within the opsin genes, recent research has shown that opsin regulatory mutations can also tune photoreceptor sensitivity and color vision. Visual sensitivity in African cichlid fishes varies as a result of the differential expression of seven opsin genes. We crossed cichlid species that express different opsin gene sets and scanned their genome for expression Quantitative Trait Loci (eQTL responsible for these differences. Our results shed light on the role that different structural, cis-, and trans-regulatory mutations play in the evolution of color vision. Results We identified 11 eQTL that contribute to the divergent expression of five opsin genes. On three linkage groups, several eQTL formed regulatory “hotspots” associated with the expression of multiple opsins. Importantly, however, the majority of the eQTL we identified (8/11 or 73% occur on linkage groups located trans to the opsin genes, suggesting that cichlid color vision has evolved primarily via trans-regulatory divergence. By modeling the impact of just two of these trans-regulatory eQTL, we show that opsin regulatory mutations can alter cichlid photoreceptor sensitivity and color vision at least as much as opsin structural mutations can. Conclusions Combined with previous work, we demonstrate that the evolution of cichlid color vision results from the interplay of structural, cis-, and especially trans-regulatory loci. Although there are numerous examples of structural and cis-regulatory mutations that contribute to phenotypic evolution, our results suggest that trans-regulatory mutations could contribute to phenotypic divergence more commonly than previously expected, especially in systems like color vision, where compensatory changes in the

Effects of cis-9, trans-11 and trans-10, cis-12 conjugated linoleic acid (CLA) isomers on immune function in healthy men

NARCIS (Netherlands)

Albers, R.; Wielen, R.P.J. van der; Brink, E.J.; Hendriks, H.F.J.; Dorovska-Taran, V.N.; Mohede, I.C.M.

2003-01-01

Objectives: To study the effects of two different mixtures of the main conjugated linoleic acid (CLA) isomers cis-9, trans-11 CLA and trans-10, cis-12 CLA on human immune function. Design: Double-blind, randomized, parallel, reference-controlled intervention study. Subjects and intervention:

Structural modification of trans-cinnamic acid using Colletotrichum acutatum

OpenAIRE

Rodrigo Velasco B.; Jesús H. Gil G.; Carlos M. García P.; Diego L. Durango R.

2012-01-01

Se estudió la biotransformación de ácido trans-cinámico mediante células completas del hongo fitopatógeno nativo colombiano Colletotrichum acutatum. Inicialmente, se evaluó la fungitoxicidad de este compuesto contraC. acutatum; el ácido trans-cinámico exhibió una toxicidad moderada a débil contra el microorganismo y aparentemente se presentó un mecanismo de detoxificación. Luego, para estudiar tal mecanismo y explorar la capacidad de este hongo para biotransformar el ácido trans-cinámico en ...

She's always a woman: Butch lesbian trans women in the lesbian community.

Science.gov (United States)

Rossiter, Hannah

2016-01-01

While the visibility and acceptance of trans women have grown globally in recent years, this progress has primarily been within a traditional, heteronormative narrative. But a growing number of trans women identify as butch lesbians and challenge this heteronormative narrative. The existence of butch trans women has created a debate on where they fit within queer and lesbian communities and how their gender performance fits within traditional butch/femme understandings of lesbian or queer relationships. This article seeks to explore the intersections of gender identity and sexual orientation that butch trans women experience when they engage with lesbian and trans communities.

Trans-jugular catheter-directed thrombolysis combined with trans-dorsalis pedis vein thrombolysis for the treatment of deep venous thrombosis of the lower limbs

International Nuclear Information System (INIS)

Qian Jiesheng; Li Zhengran; Jiang Zaibo; Zhu Kangshun; Guan Shouhai; Zhou Bing; Xu Changmou; He Keke; Shang Hong

2009-01-01

Objective: To investigate the feasibility and efficacy of trans-jugular catheter-directed thrombolysis (CDT) together with trans-dorsalis pedis vein thrombolysis for the treatment of deep venous thrombosis (DVT) of the lower limbs. Methods: Jugular vein puncture, indwelling catheter and placement of IVC filter were performed in 18 patients with DVT (study group) followed by continuous trans-jugular CDT together with trans-dorsalis pedis vein thrombolysis. During the corresponding period, 16 patients with DVT (control group) received trans-dorsalis pedis vein thrombolysis only. Results: The thrombolytic time and total dose of urokinase in study group and control group were (6.6 ± 2.3) days, (5.52 ± 2.24) x 106 units and (8.2 ± 1.4) days, (7.00 ± 1.66) x 106 units respectively. The thrombolytic time and total dose of urokinase in study group were significantly lower than that in control group (P < 0.05). After the treatment the thigh circumference and calf circumference in study group showed a reduction of (4.6 ± 2.1) cm and (4.0 ± 2.1) cm respectively, which were (3.2 ± 1.7) cm and (2.7 ± 1.5) cm respectively in control group, the difference between two groups was statistically significant (P < 0.05). The complete patent of the veins was 66.7% in study group and 31.3% in control group, the difference between two groups was significant (P < 0.05). In four cases of the study group, the filters were withdrawn through the original puncture site after the thrombus was completely dissolved. Conclusion: Trans-jugular CDT combined with trans-dorsalis pedis vein thrombolysis is an effective and safe therapeutic technique for the treatment of deep venous thrombosis of the lower extremities, moreover, the filter can be taken back via the original puncture site when the thrombus is completely dissolved. (authors)

New fluorescent azo-Schiff base Cu(II) and Zn(II) metal chelates; spectral, structural, electrochemical, photoluminescence and computational studies

Science.gov (United States)

Purtas, Fatih; Sayin, Koray; Ceyhan, Gokhan; Kose, Muhammet; Kurtoglu, Mukerrem

2017-06-01

A new Schiff base containing azo chromophore group obtained by condensation of 2-hydroxy-4-[(E)-phenyldiazenyl]benzaldehyde with 3,4-dimethylaniline (HL) are used for the syntheses of new copper(II) and zinc(II) chelates, [Cu(L)2], and [Zn(L)2], and characterized by physico-chemical and spectroscopic methods such as 1H and 13C NMR, IR, UV.-Vis. and elemental analyses. The solid state structure of the ligand was characterized by single crystal X-ray diffraction study. X-ray diffraction data was then used to calculate the harmonic oscillator model of aromaticity (HOMA) indexes for the rings so as to investigate of enol-imine and keto-amine tautomeric forms in the solid state. The phenol ring C10-C15 shows a considerable deviation from the aromaticity with HOMA value of 0.837 suggesting the shift towards the keto-amine tautomeric form in the solid state. The analytical data show that the metal to ligand ratio in the chelates was found to be 1:2. Theoretical calculations of the possible isomers of the ligand and two metal complexes are performed by using B3LYP method. Electrochemical and photoluminescence properties of the synthesized azo-Schiff bases were also investigated.

Blue and Black Cloth Targets: Effects of Size, Shape and Color on Stable Fly (L.) (Diptera: Muscidae) Attraction

Science.gov (United States)

Stable fly management has been challenging. Insecticide-treated targets made from blue and black fabric, developed in Africa, were evaluated in Louisiana and Florida to determine if they would attract and kill stable flies. Untreated targets were used to answer questions about configuration, size an...

Diphenyl (4′-(Aryldiazenylbiphenyl-4-ylamino(pyridin-3-ylmethylphosphonates as Azo Disperse Dyes for Dyeing Polyester Fabrics

Directory of Open Access Journals (Sweden)

Mohamed F. Abdel-Megeed

2013-01-01

Full Text Available Diphenyl (4′-aminobiphenyl-4-ylamino(pyridin-3-ylmethylphosphonate (1 was synthesized in 88% yield from reaction of pyridine-3-carboxaldehyde with benzidine and triphenylphosphite in the presence of titanium tetrachloride as a catalyst. Diazotization of 1 gave the corresponding diazonium salt 2 which was coupled with several hydroxyl or amino compounds to give the corresponding azo dyes 3–8 in 82–88% yields after crystallization. The dyes produced were applied to polyesters as disperse dyes and their fastness properties were elevated.

Stability of a pinned magnetic domain wall as a function of its internal configuration

Energy Technology Data Exchange (ETDEWEB)

Montaigne, F.; Duluard, A.; Briones, J.; Lacour, D.; Hehn, M. [Institut Jean Lamour, Université de Lorraine, CNRS, BP 70239, F-54506 Vandoeuvre lès Nancy (France); Childress, J. R. [HGST San Jose Research Center, 3403 Yerba Buena Rd, San Jose, California 95135 (United States)

2015-01-14

It is shown that there are many stable configurations for a domain wall pinned by a notch along a magnetic stripe. The stability of several of these configurations is investigated numerically as a function of the thickness of the magnetic film. The depinning mechanism depends on the structure of the domain wall and on the thickness of the magnetic film. In the case of a spin-valve structure, it appears that the stray fields emerging from the hard layer at the notch location influence the stability of the micromagnetic configuration. Different depinning mechanisms are thus observed for the same film thickness depending on the magnetization orientation of the propagating domain. This conclusion qualitatively explains experimental magnetoresistance measurements.

Design of Trypanosoma rangeli sialidase mutants with improved trans-sialidase activity

DEFF Research Database (Denmark)

Nyffenegger, Christian; Nordvang, Rune Thorbjørn; Jers, Carsten

2017-01-01

were analyzed via kinetics for their ability to carry out trans-sialidase reaction using CGMP and D-lactose as substrates. The sialidase variants with 15 and 16 mutations, respectively, exhibited significantly improved trans-sialidase activity for D-lactose sialylation. Our results corroborate......, that computational studies of trans-glycosylation can be a valuable input in the design of novel trans-glycosidases, but also highlight the importance of experimental validation in order to assess the performance. In conclusion, two of the seven mutants displayed a dramatic switch in specificity from hydrolysis...

Trans-orbital orbitocranial penetrating injury by pointed iron rod

Directory of Open Access Journals (Sweden)

Vinod Kumar Tewari

2015-01-01

Full Text Available Trans-orbital orbitocranial penetrating injury (TOPI by a foreign body is an extremely rare compound head injury having a potential to cause major morbidity and mortality. Preoperative radiological imaging by CT scan is very important for operative guidance, but in remote area where CT scan is not available, the patient is generally referred to tertiary level. Here we present a case which was dealt successfully without CT scan, only on the basis of stable clinical status and X-rays. We present a case of a 35-year-old man who had an accidental injury (fall from height by rod. Immediate X-ray (anteroposterior and lateral views revealed that the pointed end of the foreign body (rod was inside the ipsilateral anterior fossa via basifrontal bone up to frontal vertex, not crossing the midline. CT scan was not available and his vitals with GCS were normal (15/15. He was operated with the help of an ophthalmic surgeon by right frontotemporal craniotomy. The patient was discharged on 10 th day without any neurological deficit except restricted right eyeball movement to superolateral and ptosis. The restricted eyeball movements recovered after third month of follow up with remnant ptosis for 2 years. This case highlights an unusual case, direct visualization and repair of brain structures with higher antibiotics can save the life even in remote areas where CT scan is still not available only on the basis of stable GCS and X-rays.

Teores de ácidos graxos trans de alguns alimentos consumidos no Rio de Janeiro Trans fatty acids of some foods consumed in Rio de Janeiro, Brazil

Directory of Open Access Journals (Sweden)

Vera Lúcia Chiara

2003-06-01

Full Text Available Desconhecem-se os teores de ácidos graxos trans em diversos alimentos. Este estudo analisou os teores de ácidos graxos trans, saturados, monoinsaturados e poliinsaturados em batatas fritas, biscoitos e sorvetes. As batatas fritas foram dos tipos chips e de duas redes de fast food, os sorvetes, de duas marcas comerciais e de duas lojas de fast food, e os biscoitos, de marcas diferentes. As amostras de batatas chips e de biscoitos pertenciam a lotes distintos e foram adquiridas em supermercados da região. Analisaram-se seis amostras por produto, através de cromatografia gasosa. O valor médio dos ácidos trans de batatas fritas de redes de fast food foi de 4,74g/100g, enquanto em batatas chips estes ácidos graxos não foram detectados. Nos sorvetes os valores variaram de 0,041g a 1,41g e em biscoitos, de 2,81g a 5,60g. Biscoitos tipo cream cracker apresentaram teores de ácidos graxos trans mais altos e de insaturados mais baixos. Concluiu-se que alguns produtos apresentaram, em 100g, teores de ácidos graxos trans superiores aos recomendados para ingestão total diária em diversos países.The content of trans fatty acids in most consumed foods in Brazil is unknown. This study assessed trans saturated, monounsaturated and polyunsaturated fatty acids in samples of fried potatoes, cookies and ice cream. The analysis included: potato chips and fried potatoes from two popular fast food restaurants, ice cream of two different trademarks and from two fast food restaurants, and cookies of different trademarks. The samples of potato chips and cookies were acquired in different supermarkets in the city of Rio de Janeiro, and distinct manufacture dates were chosen. Six samples of each product were analyzed through gas chromatography. The average trans fatty acids content in fried potatoes from fast food restaurants was 4.74g/100g; in ice cream the values varied from 0.041g to 1.41g; and in cookies the values varied from 2.81g to 5.60g. No trans fatty

Sodium, saturated fat, and trans fat content per 1,000 kilocalories: temporal trends in fast-food restaurants, United States, 2000-2013.

Science.gov (United States)

Urban, Lorien E; Roberts, Susan B; Fierstein, Jamie L; Gary, Christine E; Lichtenstein, Alice H

2014-12-31

Intakes of sodium, saturated fat, and trans fat remain high despite recommendations to limit these nutrients for cardiometabolic risk reduction. A major contributor to intake of these nutrients is foods prepared outside the home, particularly from fast-food restaurants. We analyzed the nutrient content of frequently ordered items from 3 US national fast-food chains: fried potatoes (large French fries), cheeseburgers (2-oz and 4-oz), and a grilled chicken sandwich. We used an archival website to obtain data on sodium, saturated fat, and trans fat content for these items from 2000 through 2013. The amount of each nutrient per 1,000 kcal was calculated to determine whether there were trends in product reformulation. Sodium content per 1,000 kcal differed widely among the 3 chains by food item, precluding generalizations across chains. During the 14-year period, sodium content per 1,000 kcal for large French fries remained high for all 3 chains, although the range narrowed from 316-2,000 mg per 1,000 kcal in 2000 to 700-1,420 mg per 1,000 kcal in 2013. Among the items assessed, cheeseburgers were the main contributor of saturated fat, and there was little change in content per 1,000 kcal for this item during the 14-year period. In contrast, there was a sharp decline in saturated and trans fat content of large French fries per 1,000 kcal. Post-2009, the major contributor of trans fat per 1,000 kcal was cheeseburgers; trans fat content of this item remained stable during the 14-year period. With the exception of French fries, little evidence was found during the 14-year period of product reformulation by restaurants to become more consistent with dietary guidance to reduce intakes of sodium and saturated fat.

Transparent and flexible heaters based on Al:ZnO degenerate semiconductor

Science.gov (United States)

Roul, Monee K.; Obasogie, Brandon; Kogo, Gilbert; Skuza, J. R.; Mundle, R. M.; Pradhan, A. K.

2017-10-01

We report on high performance transparent Al:ZnO (AZO) thin film heaters on flexible polymer (polyethylene terephthalate) and glass substrates which demonstrate low sheet resistivity. AZO thin films were grown by radio-frequency magnetron sputtering at low Ts (below 200 °C) on flexible, transparent polyethylene terephthalate substrates that show stable and reproducible results by applying low (pain/injury therapy smart windows, automobile window defrosters, and low-cost power electronics.

Biochemical characterization of trans-sialidase TS1 variants from Trypanosoma congolense

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Dietz Frank

2011-07-01

Full Text Available Abstract Background Animal African trypanosomiasis, sleeping sickness in humans and Nagana in cattle, is a resurgent disease in Africa caused by Trypanosoma parasites. Trans-sialidases expressed by trypanosomes play an important role in the infection cycle of insects and mammals. Whereas trans-sialidases of other trypanosomes like the American T. cruzi are well investigated, relatively little research has been done on these enzymes of T. congolense. Results Based on a partial sequence and an open reading frame in the WTSI database, DNA sequences encoding for eleven T. congolense trans-sialidase 1 variants with 96.3% overall amino acid identity were amplified. Trans-sialidase 1 variants were expressed as recombinant proteins, isolated and assayed for trans-sialylation activity. The purified proteins produced α2,3-sialyllactose from lactose by desialylating fetuin, clearly demonstrating their trans-sialidase activity. Using an HPLC-based assay, substrate specificities and kinetic parameters of two variants were characterized in detail indicating differences in substrate specificities for lactose, fetuin and synthetic substrates. Both enzymes were able to sialylate asialofetuin to an extent, which was sufficient to reconstitute binding sites for Siglec-4. A mass spectrometric analysis of the sialylation pattern of glycopeptides from fetuin revealed clear but generally similar changes in the sialylation pattern of the N-glycans on fetuin catalyzed by the trans-sialidases investigated. Conclusions The identification and characterization of a trans-sialidase gene family of the African parasite T. congolense has opened new perspectives for investigating the biological role of these enzymes in Nagana and sleeping sickness. Based on this study it will be interesting to address the expression pattern of these genes and their activities in the different stages of the parasite in its infection cycle. Furthermore, these trans-sialidases have the

TiO2/Ag modified penta-bismuth hepta-oxide nitrate and its adsorption performance for azo dye removal

Institute of Scientific and Technical Information of China (English)

Eshraq Ahmed Abdullah; Abdul Halim Abdullah; Zulkarnain Zainal; Mohd Zobir Hussein; Tan Kar Ban

2012-01-01

A modified hydrophilic penta-bismuth hepta-oxide nitrate (Bi5O7NO3) surface was synthesized via a precipitation method using TiO2 and Ag as modified agents.The synthesized product was characterized by different analytical techniques.The removal efficiency was evaluated using mono- and di-sulphonated azo dyes as model pollutants.Different kinetic,isotherm and diffusion models were chosen to describe the adsorption process.X-ray photoelectron spectroscopy (XPS) results revealed no noticeable differences in the chemical states of modified adsorbent when compared to pure Bi5O7NO3; however,the presence of hydrophilic centres such as TiO2 and Ag developed positively charged surface groups and improved its adsorption performance to a wide range of azo dyes.Dyes removal was found to be a function of adsorbent dosage,initial dye concentration,solution pH and temperature.The reduction of Langrnuir 1,2-mixed order kinetics to the second or first-order kinetics could be successfully used to describe the adsorption of dyes onto the modified adsorbent.Mass transfer can be described by intra-particle diffusion at a certain stage,but it was not the rate limiting step that controlled the adsorption process.Homogenous behavior of adsorbent surface can be explored by applying Langmuir isotherm to fit the adsorption data.

Formation of trans-caffeoyl-CoA from trans-4-coumaroyl-CoA by Zn2+-dependent enzymes in cultured plant cells and its activation by an elicitor-induced pH shift

NARCIS (Netherlands)

Kneusel, R.; Matern, U.; Nicolaij, K.

1989-01-01

A novel hydroxylase activity catalyzing the formation of trans-caffeoyl-CoA from trans-4-coumaroyl-CoA was identified in crude extracts from cultured parsley cells. The extracts were less active (Vmax/Km) in converting trans-4-coumaric to trans-caffeic acid. Optimal hydroxylase activity was found at

Analysis of photoinduced birefringence in azo-dye doped films by a fast imaging technique

International Nuclear Information System (INIS)

Marino, Iari-Gabriel; Lottici, Pier Paolo

2010-01-01

In photo-birefringent films, the relationship ρ(I) between optical retardation ρ and pump irradiance I may be obtained with imaging techniques applied within a pump-probe setup. However, measurement of ρ(I) are reported only at long irradiation times and low time-resolution. In this paper we describe a polariscopic imaging technique with higher sensitivity (by a factor of ∼ 30), where the probe beam is focused on the entrance pupil of the camera ('Maxwellian view'). The technique is applied to an azo-dye doped polymeric film, obtaining the continuous ρ(I) curve after irradiation times from 10 ms to 240 ms. Exponential functions are fitted against the experimental data both as a function of time and irradiance.

Fe{sub 3}O{sub 4}@Nico-Ag magnetically recyclable nanocatalyst for azo dyes reduction

Energy Technology Data Exchange (ETDEWEB)

Kurtan, U., E-mail: ukurtan@fatih.edu.tr; Amir, Md.; Baykal, A.

2016-02-15

Graphical abstract: - Highlights: • Fe{sub 3}O{sub 4}@Nico@Ag magnetic recyclable nanocatalyst (MRC) is more effective for the reduction of azo dyes consisting of MB and MO. • It could be reused several times without significant loss in catalytic activity. • Fe{sub 3}O{sub 4}@Nico@Ag (MRCs) has been successively used for colour reduction of MO, MB, EY, RhB and their mixtures. - Abstract: In this study, we report the successful synthesis of Fe{sub 3}O{sub 4}@Nico-Ag nanocomposite as magnetically recyclable nanocatalyst (MRCs) via reflux process at 80 °C for 5 h followed by reduction of Ag{sup +}. FeCl{sub 3}·6H{sub 2}O, FeCl{sub 2}·4H{sub 2}O, AgNO{sub 3} as starting reactants and nicotinic acid as linker. The structure, morphology, thermal behaviour and magnetic properties of the product were characterized by X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), energy dispersive spectrometry (EDX), thermal gravimetry (TG) and vibrating sample magnetometry (VSM), respectively. The catalytic activity of product for various azo dyes such as methylene blue (MB), methyl orange (MO), Rhodamine B (RhB) and eosin Y (EY) and their double mixtures were studied. It was found that Fe{sub 3}O{sub 4}@Nico-Ag MRCs is an efficient catalyst and can also rapidly separated from the reaction medium using magnet without considerable loss in its catalytic activity and used several times. Fe{sub 3}O{sub 4}@Nico-Ag MRCs has potential for the treatment of industrial dye pollutants.

Synthesis and antitumor evaluation of thiophene based azo dyes incorporating pyrazolone moiety

Directory of Open Access Journals (Sweden)

Moustafa A. Gouda

2016-03-01

Full Text Available A series of thiophene incorporating pyrazolone moieties 5a–f and 6a–c were synthesized via diazo coupling of diazonium salt of 3-substituted-2-amino-4,5,6,7-tetrahydrobenzo[b]thiophenes 1a–c with 3-methyl-1H-pyrazol-5(4H-one, 3-methyl-1-phenyl-1H-pyrazol-5(4H-one or 3-amino-1H-pyrazol-5(4H-one, respectively. Newly synthesized dyes were applied to polyester fabric as disperse dyes in which their color measurements and fastness properties were evaluated. These dyes showed generally red to blue shifted color with high extinction coefficient in comparison with aniline-based azo dyes. The antitumor activity of the synthesized dyes was evaluated. The results showed clearly that most of them exhibited good activity and compounds 5c and 5d exhibited moderate activity.

Sensitive spectrophotometric determination of aceclofenac following azo dye formation with 4-carboxyl-2,6-dinitrobenzene diazonium ion.

Science.gov (United States)

Aderibigbe, Segun A; Adegoke, Olajire A; Idowu, Olakunle S; Olaleye, Sefiu O

2012-01-01

The study is a description of a sensitive spectrophotometric determination of aceclofenac following azo dye formation with 4-carboxyl-2,6-dinitrobenzenediazonium ion (CDNBD). Spot test and thin layer chromatography revealed the formation of a new compound distinct from CDNBD and aceclofenac. Optimization studies established a reaction time of 5 min at 30 degrees C after vortex mixing the drug/CDNBD for 10 s. An absorption maximum of 430 nm was selected as analytical wavelength. A linear response was observed over 1.2-4.8 μg/mL of aceclofenac with a correlation coefficient of 0.9983 and the drug combined with CDNBD at stoichiometric ratio of 2 : 1. The method has a limit of detection of 0.403 μg/mL, limit of quantitation of 1.22 μg/mL and is reproducible over a three day assessment. The method gave Sandell's sensitivity of 3.279 ng/cm2. Intra- and inter-day accuracies (in terms of errors) were less than 6% while precisions were of the order of 0.03-1.89% (RSD). The developed spectrophotometric method is of equivalent accuracy (p > 0.05) with British Pharmacopoeia, 2010 potentiometric method. It has the advantages of speed, simplicity, sensitivity and more affordable instrumentation and could found application as a rapid and sensitive analytical method of aceclofenac. It is the first described method by azo dye derivatization for the analysis of aceclofenac in bulk samples and dosage forms.

Trans-kingdom cross-talk

DEFF Research Database (Denmark)

Knip, Marijn; Constantin, Maria-Ermioni; Thordal-Christensen, Hans

2014-01-01

This review focuses on the mobility of small RNA (sRNA) molecules from the perspective of trans-kingdom gene silencing. Mobility of sRNA molecules within organisms is a well-known phenomenon, facilitating gene silencing between cells and tissues. sRNA signals are also transmitted between organism...

A trans world journey

DEFF Research Database (Denmark)

Stender, Steen; Dyerberg, Jørn; Bysted, Anette

2006-01-01

to a maximum of 2% of fat content from 2004. We assessed the potential exposure of consumers to IP-TFA by analysing popular foods in Denmark, and in 25 other countries. Fifty-five servings of French fries and chicken nuggets, 87 packages of microwave popcorn, and 393 samples of biscuits....../cakes/wafers with "partially hydrogenated vegetable fat" listed high on the food label were bought between November 2004, and February 2006. The content of IP-TFA was analysed by standardized methodology. We defined a "high trans menu" as a large size serving of French fries and nuggets, 100 g of microwave popcorn, and 100 g......A high intake of industrially produced trans fatty acids (IP-TFA) is associated with increased risk of coronary heart disease (CHD), and a daily intake as low as possible is required to minimize health risks. To achieve this at the individual level in Denmark, legislation limited IP-TFA in foods...

Regional Cooperation Towards Trans-country Natural Gas Market

DEFF Research Database (Denmark)

Shukla, P.R.; Dhar, Subash

2009-01-01

India began gas imports since 2004 through liquified natural gas (LNG) route. Imports through trans-country gas pipelines could help in bringing gas directly into the densely populated Northern part of India, which are far from domestic gas resources as well as coastal LNG terminals. The purpose ...... of this paper is to report scenarios, which quantify the impacts for India of regional cooperation to materialize trans-country pipelines. The analysis covers time period from 2005 to 2030.......India began gas imports since 2004 through liquified natural gas (LNG) route. Imports through trans-country gas pipelines could help in bringing gas directly into the densely populated Northern part of India, which are far from domestic gas resources as well as coastal LNG terminals. The purpose...

The effect of lactate unit number in compounds with azo group in the molecular core

Czech Academy of Sciences Publication Activity Database

Novotná, Vladimíra; Hamplová, Věra; Kašpar, Miroslav; Podoliak, Natalia; Bubnov, Alexej; Glogarová, Milada; Nonnenmacher, D.; Giesselmann, F.

2011-01-01

Roč. 38, č. 5 (2011), s. 649-655 ISSN 0267-8292 R&D Projects: GA AV ČR IAA100100911; GA AV ČR(CZ) GA202/09/0047; GA ČR(CZ) GAP204/11/0723 Grant - others:RFASI(RU) 02.740.11.5166; Společný projekt AV ČR-DAAD SNR(CZ) D4-CZ5/2010-2011; GA UK(CZ) SVV-2011-263303 Institutional research plan: CEZ:AV0Z10100520 Keywords : liquid crystals * ferroelectricity * chirality * azo group * antiferroelectricity Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.858, year: 2011 http://dx.doi.org/10.1080/02678292.2011.565426

A REVIEW ON EFFICACIOUS METHODS TO DECOLORIZE REACTIVE AZO DYE

Directory of Open Access Journals (Sweden)

Jagadeesan Vijayaraghavan

2013-01-01

Full Text Available This paper deals with the intensive review of reactive azo dye, Reactive Black 5. Various physicochemical methods namely photo catalysis, electrochemical, adsorption, hydrolysis and biological methods like microbial degradation, biosorption and bioaccumulation have been analyzed thoroughly along with the merits and demerits of each method. Among these various methods, biological treatment methods are found to be the best for decolorization of Reactive Black 5. With respect to dye biosorption, microbial biomass (bacteria, fungi, microalgae, etc, and outperformed macroscopic materials (seaweeds, crab shell, etc. are used for decolorization process. The use of living organisms may not be an option for the continuous treatment of highly toxic organic/inorganic contaminants. Once the toxicant concentration becomes too high or the process operated for a long time, the amount of toxicant accumulated will reach saturation. Beyond this point, an organism's metabolism may be interrupted, resulting in death of the organism. This scenario is not existed in the case of dead biomass, which is flexible to environmental conditions and toxicant concentrations. Thus, owing to its favorable characteristics, biosorption has received much attention in recent years.

Study of the alkaline cations complexation by photo-isomerizable calixarenes; Etude de la complexation de cations alcalins par des calixarenes photoisomerisables

Energy Technology Data Exchange (ETDEWEB)

Reynier, N.

1996-04-25

The first step to reduce the volume and the toxicity of radioactive waste coming from the spent fuel reprocessing is to separate long life radioisotopes from others ones with a shorter period. The aim of this study is to show that the control of the two phenomenons, complexation of the cation by the calixarenes and its de-complexation, can be envisaged by the introduction on the molecule of a chromophore group, azo benzene, able to modify the complexing site structure of the calixarenes with an isomerization trans-cis induced by ultraviolet radiation, and isomerization cis-trans thermally induced by a visible radiation. (N.C.). 112 refs., 78 figs., 23 tabs.

Magneto-hydrodynamically stable axisymmetric mirrorsa)

Science.gov (United States)

Ryutov, D. D.; Berk, H. L.; Cohen, B. I.; Molvik, A. W.; Simonen, T. C.

2011-09-01

Making axisymmetric mirrors magnetohydrodynamically (MHD) stable opens up exciting opportunities for using mirror devices as neutron sources, fusion-fission hybrids, and pure-fusion reactors. This is also of interest from a general physics standpoint (as it seemingly contradicts well-established criteria of curvature-driven instabilities). The axial symmetry allows for much simpler and more reliable designs of mirror-based fusion facilities than the well-known quadrupole mirror configurations. In this tutorial, after a summary of classical results, several techniques for achieving MHD stabilization of the axisymmetric mirrors are considered, in particular: (1) employing the favorable field-line curvature in the end tanks; (2) using the line-tying effect; (3) controlling the radial potential distribution; (4) imposing a divertor configuration on the solenoidal magnetic field; and (5) affecting the plasma dynamics by the ponderomotive force. Some illuminative theoretical approaches for understanding axisymmetric mirror stability are described. The applicability of the various stabilization techniques to axisymmetric mirrors as neutron sources, hybrids, and pure-fusion reactors are discussed; and the constraints on the plasma parameters are formulated.

Magneto-hydrodynamically stable axisymmetric mirrors

Energy Technology Data Exchange (ETDEWEB)

Ryutov, D. D.; Cohen, B. I.; Molvik, A. W. [Lawrence Livermore National Laboratory, Livermore, California 94551 (United States); Berk, H. L. [University of Texas, Austin, Texas 78712 (United States); Simonen, T. C. [University of California, Berkeley, California 94720 (United States)

2011-09-15

Making axisymmetric mirrors magnetohydrodynamically (MHD) stable opens up exciting opportunities for using mirror devices as neutron sources, fusion-fission hybrids, and pure-fusion reactors. This is also of interest from a general physics standpoint (as it seemingly contradicts well-established criteria of curvature-driven instabilities). The axial symmetry allows for much simpler and more reliable designs of mirror-based fusion facilities than the well-known quadrupole mirror configurations. In this tutorial, after a summary of classical results, several techniques for achieving MHD stabilization of the axisymmetric mirrors are considered, in particular: (1) employing the favorable field-line curvature in the end tanks; (2) using the line-tying effect; (3) controlling the radial potential distribution; (4) imposing a divertor configuration on the solenoidal magnetic field; and (5) affecting the plasma dynamics by the ponderomotive force. Some illuminative theoretical approaches for understanding axisymmetric mirror stability are described. The applicability of the various stabilization techniques to axisymmetric mirrors as neutron sources, hybrids, and pure-fusion reactors are discussed; and the constraints on the plasma parameters are formulated.

Thiyl radical-induced cis-trans-isomerization of arachidonic acid inhibits prostaglandin metabolism

International Nuclear Information System (INIS)

Kratzsch, S.; Droessler, K.; Sprinz, H.; Brede, O.

2002-01-01

Complete text of publication follows. Thiyl radicals radiolytically generated from thiophenol in methanolic solution are known to isomerise double bonds of poly-unsaturated fatty acids (PUFA). γ-irradiating of such a system containing all-cis 5,8,11,14 eicosatetraenoic acid (arachidonic acid, AA) with low doses (0.1-0.8 kGy) results in a mixture of 8 to 32% mono-trans-isomers. Here we report about the influence of mono-trans-AA on the primary steps of AA-metabolism and prostaglandin synthesis, catalysed by cyclooxygenase (COX). In the cell-free model system the reaction of COX-1 with AA was analysed by controlling the oxygen level during the enzymatic reaction. As an example, a mixture of a low quantity of mono-trans-isomerized AA (10%) and 90% all-cis-isomer exhibits a marked reduced oxygen consumption by 45%. As further proofs - the yield of reactive oxygen species (ROS) generated by the COX-coupled peroxidase reaction was detected, - and the COX-1 activity in presence of different amounts of trans-AA was characterized using a photometric assay based on the oxidation of TMPD. All these methods indicated semiquantitatively a reduced activity of COX-1, depending on the trans-isomer yield. Therefore, an inhibition of COX-1 activity by only one trans-double-bond in AA could be concluded. Furthermore, in vitro cell-line experiments were performed analysing the influence of mono-trans-isomerized AA on the activity of the cell-own COX-2. Hence, VD 3 -differentiated and LPS-stimulated monocyte-like cells were incubated with mono-trans-AA and ROS-production was detected by the chemiluminescence measurements mentioned above. Compared to the reaction with all-cis-AA we found a considerable lowered formation of ROS. Likewise, we obtained a reduced PGE 2 -expression between 15 and 40% for cells treated with 8 to 29% trans-AA. The model as well as in vivo experiments demonstrate an inhibition effect of mono-trans-AA and give rise for postulating an enzyme blocking mechanism

Disintegration of aerobic granules induced by trans-2-decenoic acid.

Science.gov (United States)

Cai, Pei-Jie; Xiao, Xiang; He, Yan-Rong; Li, Wen-Wei; Yu, Lei; Yu, Han-Qing

2013-01-01

One current major hurdle to practical implementation of aerobic granule technology is the frequent occurrence of granule disintegration during long-term operation. However, the mechanism behind this is largely unclear today. Here, 2-decenoic acid, which has been previously demonstrated to be released by Pseudomonas aeruginosa and disperse biofilms, was found to also induce the disintegration of aerobic granules. A comparison of the solution compositions from samples of only trans-2-decenoic acid, only aerobic granules, and granules added with trans-2-decenoic acid shows that bacteria and extracellular polymeric substances (EPS) were stripped from granule surface upon trans-2-decenoic acid dosing. Due to the possible toxicity of trans-2-decenoic acid at a saturation concentration, the disintegrated granules and the milky suspension in the disintegration test showed a significantly lower oxygen uptake rate than the un-integrated granules. This work suggests that trans-2-decenoic acid released by microbes might play a critical role in regulating the disintegration of aerobic granules. Copyright © 2012 Elsevier Ltd. All rights reserved.

Identification of isomers in the gas phase and as adsorbates by near-edge X-ray absorption fine structure spectroscopy: Cis- and trans-stilbene

International Nuclear Information System (INIS)

Püttner, Ralph; Schmidt-Weber, Philipp; Kampen, Thorsten; Kolczewski, Christine; Hermann, Klaus; Horn, Karsten

2017-01-01

Highlights: • NEXAFS spectra of the cis- and trans-isomer of stilbene reveal distinct differences by which the isomers can be distinguished. • DFT calculations using the transition potential approach assign specific transitions that are different in the two isomers. • On Si(100), these differences in NEXAFS are also observed, suggesting that their conformations survive in the bonding situation. • NEXAFS is thus shown to be a sensitive tool to distinguish isomers in adsorbed species. - Abstract: Near-edge x-ray absorption fine structure spectra of the cis- and trans-isomers of stilbene in the gas phase reveal clear differences, which are analyzed by results from density-functional theory calculations using the transition potential approach. The differences between the two species also occur in stilbene adsorbed on Si(100), opening the way towards studying structural changes in molecules in different surface environments, and configurational switching in organic molecules on surfaces in particular.

Identification of isomers in the gas phase and as adsorbates by near-edge X-ray absorption fine structure spectroscopy: Cis- and trans-stilbene

Energy Technology Data Exchange (ETDEWEB)

Püttner, Ralph [Department of Physics, Freie Universität Berlin, 14195 Berlin (Germany); Schmidt-Weber, Philipp [Fritz Haber Institute of the Max Planck Society, 14195 Berlin (Germany); Kampen, Thorsten [SPECS Surface Nano Analysis GmbH, 13355 Berlin (Germany); Kolczewski, Christine [Deutsches Museum München, 80538 Munich (Germany); Hermann, Klaus [Fritz Haber Institute of the Max Planck Society, 14195 Berlin (Germany); Horn, Karsten, E-mail: horn@fhi-berlin.mpg.de [Fritz Haber Institute of the Max Planck Society, 14195 Berlin (Germany)

2017-02-15

Highlights: • NEXAFS spectra of the cis- and trans-isomer of stilbene reveal distinct differences by which the isomers can be distinguished. • DFT calculations using the transition potential approach assign specific transitions that are different in the two isomers. • On Si(100), these differences in NEXAFS are also observed, suggesting that their conformations survive in the bonding situation. • NEXAFS is thus shown to be a sensitive tool to distinguish isomers in adsorbed species. - Abstract: Near-edge x-ray absorption fine structure spectra of the cis- and trans-isomers of stilbene in the gas phase reveal clear differences, which are analyzed by results from density-functional theory calculations using the transition potential approach. The differences between the two species also occur in stilbene adsorbed on Si(100), opening the way towards studying structural changes in molecules in different surface environments, and configurational switching in organic molecules on surfaces in particular.

Shifting Paradigms: Moving beyond "Trans 101" in Sexuality Education

Science.gov (United States)

Green, Eli R.

2010-01-01

Trans-inclusive sexuality education can be complex, confusing, and outright intimidating for even the most seasoned sexuality educator to teach. Historically, standalone "Trans 101" sessions have successfully raised awareness about the highly marginalized transgender community. However, their potential success has been limited by being taught in…

Illela border market: origin and contributions to trans-border ...

African Journals Online (AJOL)

Illela border market: origin and contributions to trans-border relations between Nigeria and Niger republic. ... cordial relations between her and her immediate neighbours and thus stem the scourge of smuggling and other trans-border crimes which have negatively affected the Nigerian economy and her international image.

Oxygen atom transfer from a trans-dioxoruthenium(VI) complex to nitric oxide.

Science.gov (United States)

Man, Wai-Lun; Lam, William W Y; Ng, Siu-Mui; Tsang, Wenny Y K; Lau, Tai-Chu

2012-01-02

In aqueous acidic solutions trans-[Ru(VI)(L)(O)(2)](2+) (L=1,12-dimethyl-3,4:9,10-dibenzo-1,12-diaza-5,8-dioxacyclopentadecane) is rapidly reduced by excess NO to give trans-[Ru(L)(NO)(OH)](2+). When ≤1 mol equiv NO is used, the intermediate Ru(IV) species, trans-[Ru(IV)(L)(O)(OH(2))](2+), can be detected. The reaction of [Ru(VI)(L)(O)(2)](2+) with NO is first order with respect to [Ru(VI)] and [NO], k(2)=(4.13±0.21)×10(1) M(-1) s(-1) at 298.0 K. ΔH(≠) and ΔS(≠) are (12.0±0.3) kcal mol(-1) and -(11±1) cal mol(-1) K(-1), respectively. In CH(3)CN, ΔH(≠) and ΔS(≠) have the same values as in H(2)O; this suggests that the mechanism is the same in both solvents. In CH(3)CN, the reaction of [Ru(VI)(L)(O)(2)](2+) with NO produces a blue-green species with λ(max) at approximately 650 nm, which is characteristic of N(2)O(3). N(2)O(3) is formed by coupling of NO(2) with excess NO; it is relatively stable in CH(3)CN, but undergoes rapid hydrolysis in H(2)O. A mechanism that involves oxygen atom transfer from [Ru(VI)(L)(O)(2)](2+) to NO to produce NO(2) is proposed. The kinetics of the reaction of [Ru(IV)(L)(O)(OH(2))](2+) with NO has also been investigated. In this case, the data are consistent with initial one-electron O(-) transfer from Ru(IV) to NO to produce the nitrito species [Ru(III)(L)(ONO)(OH(2))](2+) (k(2)>10(6) M(-1) s(-1)), followed by a reaction with another molecule of NO to give [Ru(L)(NO)(OH)](2+) and NO(2)(-) (k(2)=54.7 M(-1) s(-1)). Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Metabolism of all-trans-retinoic acid and all-trans-retinyl acetate. Demonstration of common physiological metabolites in rat small intestinal mucosa and circulation

International Nuclear Information System (INIS)

Cullum, M.E.; Zile, M.H.

1985-01-01

The kinetics and metabolism of physiological doses of all-trans-retinoic acid were examined in blood and small intestinal mucosa of vitamin A-depleted rats. A major portion of intrajugularly injected retinoic acid is rapidly (within 2 min) sequestered by tissues; subsequently 13-cis-retinoic acid and polar metabolites are released into circulation. All-trans-retinoic acid appears in small intestinal epithelium within 2 min after dosing and is the major radioactive compound there for at least 2 h. Retinoyl glucuronide and 13-cis-retinoic acid are early metabolites of all-trans-retinoic acid in the small intestine of bile duct-cannulated rats. Retinoyl glucuronide, the major metabolite of retinoic acid intestinal epithelium, in contrast to other polar metabolites, was not detected in circulation. An examination of [ 3 H]retinyl acetate metabolites under steady state conditions in vitamin A-repleted rats demonstrates the occurrence of all-trans-retinoic acid and 13-cis-retinoic acid in circulation and in intestinal epithelium, in a pattern similar to that found after injection of retinoic acid into vitamin A-depleted rats. These data establish that all-trans-retinoic acid, 13-cis-retinoic acid, and retinoyl glucuronide are physiological metabolites of vitamin A in target tissues, and therefore are important candidates as mediators of the biological effect of the vitamin

Nonhydrogenated cottonseed oil can be used as a deep fat frying medium to reduce trans-fatty acid content in french fries.

Science.gov (United States)

Daniel, Darla R; Thompson, Leslie D; Shriver, Brent J; Wu, Chih-Kang; Hoover, Linda C

2005-12-01

The purpose of this research study was to evaluate the fatty acid profile, in particular trans-fatty acids, of french fries fried in nonhydrogenated cottonseed oil as compared with french fries fried in partially hydrogenated canola oil and french fries fried in partially hydrogenated soybean oil. Cottonseed oil, partially hydrogenated canola oil, and partially hydrogenated soybean oil were subjected to a temperature of 177 degrees C for 8 hours per day, and six batches of french fries were fried per day for 5 consecutive days. French fries were weighed before frying, cooked for 5 minutes, allowed to drain, and reweighed. Oil was not replenished and was filtered once per day. Both the oil and the french fries were evaluated to determine fatty acid profiles, trans-fatty acids, and crude fat. A randomized block design with split plot was used to analyze the data collected. Least-squares difference was used as the means separation test. No significant differences were found between fries prepared in the three oil types for crude fat. Fatty acid profiles for the french fries remained stable. The french fries prepared in cottonseed oil were significantly lower in trans-fatty acids. The combined total of the trans-fatty acid content and saturated fatty acid content were lower in french fries prepared in cottonseed oil. Because deep fat frying remains a popular cooking technique, health professionals should educate the public and the food service industry on the benefits of using nonhydrogenated cottonseed oil as an alternative to the commonly used hydrogenated oils.

A stable high-speed rotational transmission system based on nanotubes

International Nuclear Information System (INIS)

Cai, Kun; Yin, Hang; Wei, Ning; Chen, Zhen; Shi, Jiao

2015-01-01

A stable rotational transmission system is designed with a single-walled carbon nanotube (SWCNT)-based motor and double-walled carbon nanotubes (DWCNTs)-based bearing. The system response is investigated using molecular dynamics (MD) simulation. It is found that the rotating motor can actuate the rotation of the inner tube in bearing because of the attraction between the two adjacent coaxial ends of motor and rotor (the inner tube in bearing). To have a stable nanostructure, each carbon atom on the adjacent ends of motor and rotor is bonded with a hydrogen atom. To obtain a stable high-speed rotational transmission system, both an armchair and a zigzag model are used in MD simulation. In each model, the motor with different diameters and rotational speeds is employed to examine the rotational transmission of corresponding DWCNTs. It is demonstrated that the long range van der Waals interaction between the adjacent ends of motor and rotor leads to a stable configuration of the adjacent ends, and further leads to a stable rotation of rotor when driven by a high-speed motor. As compared with the armchair model, the rotor in the zigzag model could reach a stable rotation mode much easier

Reprogramming the Dynamin 2 mRNA by Spliceosome-mediated RNA Trans-splicing

Directory of Open Access Journals (Sweden)

Delphine Trochet

2016-01-01

Full Text Available Dynamin 2 (DNM2 is a large GTPase, ubiquitously expressed, involved in membrane trafficking and regulation of actin and microtubule cytoskeletons. DNM2 mutations cause autosomal dominant centronuclear myopathy which is a rare congenital myopathy characterized by skeletal muscle weakness and histopathological features including nuclear centralization in absence of regeneration. No curative treatment is currently available for the DNM2-related autosomal dominant centronuclear myopathy. In order to develop therapeutic strategy, we evaluated here the potential of Spliceosome-Mediated RNA Trans-splicing technology to reprogram the Dnm2-mRNA in vitro and in vivo in mice. We show that classical 3′-trans-splicing strategy cannot be considered as accurate therapeutic strategy regarding toxicity of the pre-trans-splicing molecules leading to low rate of trans-splicing in vivo. Thus, we tested alternative strategies devoted to prevent this toxicity and enhance frequency of trans-splicing events. We succeeded to overcome the toxicity through a 5′-trans-splicing strategy which also allows detection of trans-splicing events at mRNA and protein levels in vitro and in vivo. These results suggest that the Spliceosome-Mediated RNA Trans-splicing strategy may be used to reprogram mutated Dnm2-mRNA but highlight the potential toxicity linked to the molecular tools which have to be carefully investigated during preclinical development.

Trans-dissemination of exosomes from HIV-1-infected cells fosters both HIV-1 trans-infection in resting CD4+ T lymphocytes and reactivation of the HIV-1 reservoir.

Science.gov (United States)

Chiozzini, Chiara; Arenaccio, Claudia; Olivetta, Eleonora; Anticoli, Simona; Manfredi, Francesco; Ferrantelli, Flavia; d'Ettorre, Gabriella; Schietroma, Ivan; Andreotti, Mauro; Federico, Maurizio

2017-09-01

Intact HIV-1 and exosomes can be internalized by dendritic cells (DCs) through a common pathway leading to their transmission to CD4 + T lymphocytes by means of mechanisms defined as trans-infection and trans-dissemination, respectively. We previously reported that exosomes from HIV-1-infected cells activate both uninfected quiescent CD4 + T lymphocytes, which become permissive to HIV-1, and latently infected cells, with release of HIV-1 particles. However, nothing is known about the effects of trans-dissemination of exosomes produced by HIV-1-infected cells on uninfected or latently HIV-1-infected CD4 + T lymphocytes. Here, we report that trans-dissemination of exosomes from HIV-1-infected cells induces cell activation in resting CD4 + T lymphocytes, which appears stronger with mature than immature DCs. Using purified preparations of both HIV-1 and exosomes, we observed that mDC-mediated trans-dissemination of exosomes from HIV-1-infected cells to resting CD4 + T lymphocytes induces efficient trans-infection and HIV-1 expression in target cells. Most relevant, when both mDCs and CD4 + T lymphocytes were isolated from combination anti-retroviral therapy (ART)-treated HIV-1-infected patients, trans-dissemination of exosomes from HIV-1-infected cells led to HIV-1 reactivation from the viral reservoir. In sum, our data suggest a role of exosome trans-dissemination in both HIV-1 spread in the infected host and reactivation of the HIV-1 reservoir.

Phosphorus K4 Crystal: A New Stable Allotrope

OpenAIRE

Jie Liu; Shunhong Zhang; Yaguang Guo; Qian Wang

2016-01-01

The intriguing properties of phosphorene motivate scientists to further explore the structures and properties of phosphorus materials. Here, we report a new allotrope named K 4 phosphorus composed of three-coordinated phosphorus atoms in non-layered structure which is not only dynamically and mechanically stable, but also possesses thermal stability comparable to that of the orthorhombic black phosphorus (A17). Due to its unique configuration, K 4 phosphorus exhibits exceptional properties: i...

Hollow Palladium Nanoparticles Facilitated Biodegradation of an Azo Dye by Electrically Active Biofilms

KAUST Repository

Kalathil, Shafeer; Chaudhuri, Rajib Ghosh

2016-01-01

Dye wastewater severely threatens the environment due to its hazardous and toxic effects. Although many methods are available to degrade dyes, most of them are far from satisfactory. The proposed research provides a green and sustainable approach to degrade an azo dye, methyl orange, by electrically active biofilms (EABs) in the presence of solid and hollow palladium (Pd) nanoparticles. The EABs acted as the electron generator while nanoparticles functioned as the electron carrier agents to enhance degradation rate of the dye by breaking the kinetic barrier. The hollow Pd nanoparticles showed better performance than the solid Pd nanoparticles on the dye degradation, possibly due to high specific surface area and cage effect. The hollow cavities provided by the nanoparticles acted as the reaction centers for the dye degradation.

Hollow Palladium Nanoparticles Facilitated Biodegradation of an Azo Dye by Electrically Active Biofilms

KAUST Repository

Kalathil, Shafeer

2016-08-04

Dye wastewater severely threatens the environment due to its hazardous and toxic effects. Although many methods are available to degrade dyes, most of them are far from satisfactory. The proposed research provides a green and sustainable approach to degrade an azo dye, methyl orange, by electrically active biofilms (EABs) in the presence of solid and hollow palladium (Pd) nanoparticles. The EABs acted as the electron generator while nanoparticles functioned as the electron carrier agents to enhance degradation rate of the dye by breaking the kinetic barrier. The hollow Pd nanoparticles showed better performance than the solid Pd nanoparticles on the dye degradation, possibly due to high specific surface area and cage effect. The hollow cavities provided by the nanoparticles acted as the reaction centers for the dye degradation.

Hollow Palladium Nanoparticles Facilitated Biodegradation of an Azo Dye by Electrically Active Biofilms

Directory of Open Access Journals (Sweden)

Shafeer Kalathil

2016-08-01

Full Text Available Dye wastewater severely threatens the environment due to its hazardous and toxic effects. Although many methods are available to degrade dyes, most of them are far from satisfactory. The proposed research provides a green and sustainable approach to degrade an azo dye, methyl orange, by electrically active biofilms (EABs in the presence of solid and hollow palladium (Pd nanoparticles. The EABs acted as the electron generator while nanoparticles functioned as the electron carrier agents to enhance degradation rate of the dye by breaking the kinetic barrier. The hollow Pd nanoparticles showed better performance than the solid Pd nanoparticles on the dye degradation, possibly due to high specific surface area and cage effect. The hollow cavities provided by the nanoparticles acted as the reaction centers for the dye degradation.

After runaway: The trans-Hill stage of planetesimal growth

International Nuclear Information System (INIS)

Lithwick, Yoram

2014-01-01

When planetesimals begin to grow by coagulation, they first enter an epoch of runaway, during which the biggest bodies grow faster than all the others. The questions of how runaway ends and what comes next have not been answered satisfactorily. We show that runaway is followed by a new stage—the 'trans-Hill stage'—that commences when the bodies that dominate viscous stirring ('big bodies') become trans-Hill, i.e., when their Hill velocity matches the random speed of the small bodies they accrete. Subsequently, the small bodies' random speed grows in lockstep with the big bodies' sizes, such that the system remains in the trans-Hill state. Trans-Hill growth is crucial for determining the efficiency of growing big bodies, as well as their growth timescale and size spectrum. Trans-Hill growth has two sub-stages. In the earlier one, which occurs while the stirring bodies remain sufficiently small, the evolution is collisionless, i.e., collisional cooling among all bodies is irrelevant. The efficiency of forming big bodies in this collisionless sub-stage is very low, ∼10α << 1, where α ∼ 0.005(a/AU) –1 is the ratio between the physical size of a body and its Hill radius. Furthermore, the size spectrum is flat (equal mass per size decade, i.e., q = 4). This collisionless trans-Hill solution explains results from previous coagulation simulations for both the Kuiper Belt and the asteroid belt. The second trans-Hill sub-stage commences once the stirring bodies grow big enough (>α –1 × the size of the accreted small bodies). After that time, collisional cooling among small bodies controls the evolution. The efficiency of forming big bodies rises and the size spectrum becomes more top heavy. Trans-Hill growth can terminate in one of two ways, depending on the sizes of the small bodies. First, mutual accretion of big bodies can become significant and conglomeration proceeds until half of the total mass is converted into big bodies

Homological stability for unordered configuration spaces

DEFF Research Database (Denmark)

Randal-Williams, Oscar

2013-01-01

This paper consists of two related parts. In the first part we give a self-contained proof of homological stability for the spaces C_n(M;X) of configurations of n unordered points in a connected open manifold M with labels in a path-connected space X, with the best possible integral stability range...... of the spaces C_n(M) can be considered stable when M is a closed manifold. In this case there are no stabilisation maps, but one may still ask if the dimensions of the homology groups over some field stabilise with n. We prove that this is true when M is odd-dimensional, or when the field is F_2 or Q...

A highly versatile and easily configurable system for plant electrophysiology.

Science.gov (United States)

Gunsé, Benet; Poschenrieder, Charlotte; Rankl, Simone; Schröeder, Peter; Rodrigo-Moreno, Ana; Barceló, Juan

2016-01-01

In this study we present a highly versatile and easily configurable system for measuring plant electrophysiological parameters and ionic flow rates, connected to a computer-controlled highly accurate positioning device. The modular software used allows easy customizable configurations for the measurement of electrophysiological parameters. Both the operational tests and the experiments already performed have been fully successful and rendered a low noise and highly stable signal. Assembly, programming and configuration examples are discussed. The system is a powerful technique that not only gives precise measuring of plant electrophysiological status, but also allows easy development of ad hoc configurations that are not constrained to plant studies. •We developed a highly modular system for electrophysiology measurements that can be used either in organs or cells and performs either steady or dynamic intra- and extracellular measurements that takes advantage of the easiness of visual object-oriented programming.•High precision accuracy in data acquisition under electrical noisy environments that allows it to run even in a laboratory close to electrical equipment that produce electrical noise.•The system makes an improvement of the currently used systems for monitoring and controlling high precision measurements and micromanipulation systems providing an open and customizable environment for multiple experimental needs.

Monoclonal antibodies to DNA modified with cis- or trans-diamminedichloroplatinum(II)

International Nuclear Information System (INIS)

Sundquist, W.I.; Lippard, S.J.; Stollar, B.D.

1987-01-01

Murine monoclonal antibodies that bind selectively to adducts formed on DNA by the antitumor drug cis-diamminedichloroplatinum(II), cis-DDP, or to the chemothrapeutically inactive trans isomer trans-DDP were elicited by immunization with calf thymus DNA modified with either cis- or trans-DDP at ratios of bound platinum per nucleotide, (D/N)/sub b/, of 0.06-0.08. The binding of two monoclonal antibodies to cis-DDP-modified DNA was competitively inhibited in an enzyme-linked immunosorbent assay (ELISA) by 4-6 nM concentrations of cis-DDP bound to DNA. Adducts formed by cis-DDP on other synthetic DNA polymers did not inhibit antibody binding to cis-DDP-DNA. The biologically active compounds [Pt(en)Cl 2 ], [Pt(dach)Cl 2 ], and [Pt(NH 3 ) 2 (cbdca)] (carboplatin) all formed antibody-detectable adducts on DNA, whereas the inactive platinum complexes trans-DDP and [Pt(dien)Cl]Cl (dien, diethylenetriamine) did not. The monoclonal antibodies therefore recognize a bifunctional Pt-DNA adduct with cis stereochemistry in which platinum is coordinated by two adjacent guanines or, to a lesser degree, by adjacent adenine and guanine. A monoclonal antibody raised against trans-DDP-DNA was competitively inhibited in an ELISA by 40 nM trans-DDP bound to DNA. This antibody crossreacted with unmodified, denatured DNA. The recognition of cis- or trans-DDP-modified DNAs by monoclonal antibodies thus parallels the known modes of DNA binding of these compounds and may correlate with their biological activities

Conceptualizing Embedded Configuration

DEFF Research Database (Denmark)

Oddsson, Gudmundur Valur; Hvam, Lars; Lysgaard, Ole

2006-01-01

and services. The general idea can be named embedded configuration. In this article we intend to conceptualize embedded configuration, what it is and is not. The difference between embedded configuration, sales configuration and embedded software is explained. We will look at what is needed to make embedded...... configuration systems. That will include requirements to product modelling techniques. An example with consumer electronics will illuminate the elements of embedded configuration in settings that most can relate to. The question of where embedded configuration would be relevant is discussed, and the current...

Trans people's experiences with assisted reproduction services: a qualitative study.

Science.gov (United States)

James-Abra, S; Tarasoff, L A; Green, D; Epstein, R; Anderson, S; Marvel, S; Steele, L S; Ross, L E

2015-06-01

What are the experiences of trans persons (i.e. those whose gender identity does not match the gender assigned to them at birth) who sought or accessed assisted reproduction (AR) services in Ontario, Canada, between 2007 and 2010? The majority of trans persons report negative experiences with AR service providers. Apart from research examining desire to have children among trans people, most of the literature on this topic has debated the ethics of assisting trans persons to become parents. To-date, all of the published research concerning trans persons' experiences with AR services is solely from the perspective of service providers; no studies have examined the experiences of trans people themselves. Secondary qualitative research study of data from nine trans-identified people and their partners (total n = 11) collected as part of a community-based study of access to AR services for sexual and gender minority people between 2010 and 2012. Trans-identified volunteers (and their partners, when applicable) who had used or attempted to access AR services since 2007 from across Ontario, Canada, participated in a 60-90 minute, semi-structured qualitative interview. Qualitative analysis was performed using a descriptive phenomenological approach. Emerging themes were continually checked against the data as part of an iterative process. The data highlight barriers to accessing AR services for trans people. Participant recommendations for improving AR service provision to better meet the needs of this population are presented. These recommendations address the following areas: (i) AR service provider education and training; (ii) service provider and clinic practices and (iii) clinic environment. The majority of study participants were trans people who identified as men and who resided in major urban areas; those living in smaller communities may have different experiences that were not adequately captured in this analysis. While existing literature debates the ethics of

The importance of trans-generational effects in Lepidoptera

OpenAIRE

Woestmann, Luisa; Saastamoinen, Marjo

2016-01-01

The importance of trans-generational effects in shaping an individuals' phenotype and fitness, and consequently even impacting population dynamics is increasingly apparent. Most of the research on trans-generational effects still focuses on plants, mammals, and birds. In the past few years, however, increasing number of studies, especially on maternal effects, have highlighted their importance also in many insect systems. Lepidoptera, specifically butterflies, have been used as model systems ...

Experimental evaluation of the pure configurational stress assumption in the flow dynamics of entangled polymer melts

DEFF Research Database (Denmark)

Rasmussen, Henrik K.; Bejenariu, Anca Gabriela; Hassager, Ole

2010-01-01

to the flow in the non-linear flow regime. This has allowed highly elastic measurements within the limit of pure orientational stress, as the time of the flow was considerably smaller than the Rouse time. A Doi-Edwards [J. Chem. Soc., Faraday Trans. 2 74, 1818-1832 (1978)] type of constitutive model...... with the assumption of pure configurational stress was accurately able to predict the startup as well as the reversed flow behavior. This confirms that this commonly used theoretical picture for the flow of polymeric liquids is a correct physical principle to apply. c 2010 The Society of Rheology. [DOI: 10.1122/1.3496378]...

Science and trans-science in standard setting

International Nuclear Information System (INIS)

Majone, G.

1984-01-01

Standard-setting is a blending of scientific, trans-scientific, and political elements which result in a number of consequences. Health standards, for example, are influenced by biological and philosophical assumptions and scientific traditions, with the dose-response function treated as a trans-scientific question because of scientific uncertainties. Costs and benefits and other values besides health, safety, or environment also enter into the balancing of regulatory decisions and keep regulations from a purely scientific knowledge is desirable. Recommendations that industry be self-regulatory reflect a shift in emphasis from legal enforcement to information-based compliance

TransAlta 2003 annual report

International Nuclear Information System (INIS)

2004-01-01

This annual report presents financial information from TransAlta Corp., along with a review of its operations throughout 2003 and a summary of the how the electric utility has performed in terms of power generation, independent power producers, transmission and energy marketing. TransAlta is one of the largest non-regulated power generation and wholesale marketing companies in Canada. It's assets include coal-fired, gas-fired, hydro and renewable generation facilities in Canada, the United States, Mexico and Australia. Reported earnings in 2003 were $1.26 per share compared to $1.17 in 2002. The strong first quarter was followed by harsh market conditions, low water levels which affected hydro production, and pricing restrictions in Ontario that reduced contribution from the Sarnia plant. This report outlines the utility's progress in increasing revenue and producing more power. In 2003, unplanned outages were reduced by 7 per cent and injury frequency rate was reduced by 27 per cent. The installation of 114 wind turbines in Fort Macleod, Alberta, increased TransAlta's renewable energy capacity to 3.7 per cent in 2003. The wind farm produces 75 MW of electricity, enough to power more than 32,500 homes annually. This report summarized the company's energy resource activities and presented an operations review as well as consolidated financial statements and common share information. This included the utility's assets, liabilities, revenues, expenses and cash flows. Revenue and expenditure statements were summarized by source. refs., tabs., figs

DFT Study of the Structure, Reactivity, Natural Bond Orbital and Hyperpolarizability of Thiazole Azo Dyes

Directory of Open Access Journals (Sweden)

Osman I. Osman

2017-02-01

Full Text Available The structure, reactivity, natural bond orbital (NBO, linear and nonlinear optical (NLO properties of three thiazole azo dyes (A, B and C were monitored by applying B3LYP, CAM-B3LYP and ωB97XD functionals with 6-311++G** and aug-cc-pvdz basis sets. The geometrical parameters,dipolemoments,HOMO-LUMO(highest occupied molecular orbital,lowest unoccupied molecular orbital energy gaps, absorption wavelengths and total hyperpolarizabilities were investigated in carbon tetrachloride (CCl4 chloroform (CHCl3, dichloromethane (CH2Cl2 and dimethlysulphoxide (DMSO. The donor methoxyphenyl group deviates from planarity with the thiazole azo moiety by ca. 38◦; while the acceptor dicyanovinyl, indandione and dicyanovinylindanone groups diverge by ca. 6◦. The HOMOs for the three dyes are identical. They spread over the methoxyphenyl donor moiety, the thiazole and benzene rings as π-bonding orbitals. The LUMOs are shaped up by the nature of the acceptor moieties. The LUMOs of the A, B and C dyes extend over the indandione, malononitrile and dicyanovinylindanone acceptor moieties, respectively, as π-antibonding orbitals. The HOMO-LUMO splittings showed that Dye C is much more reactive than dyes A and B. Compared to dyes A and B, Dye C yielded a longer maximum absorption wavelength because of the stabilization of its LUMOs relative to those of the other two. The three dyes show solvatochromism accompanied by significant increases in hyperpolarizability. The enhancement of the total hyperpolarizability of C compared to those of A and B is due to the cumulative action of the long π-conjugation of the indanone ring and the stronger electron-withdrawing ability of the dicyanovinyl moiety that form the dicyanovinylindanone acceptor group. These findings are facilitated by a natural bond orbital (NBO technique. The very high total hyperpolarizabilities of the three dyes define their potent nonlinear optical (NLO behaviour.

Strange Bedfellows: Anachronisms, Identity Politics, and the Queer Case of Trans.

Science.gov (United States)

Gailey, Nerissa

2017-01-01

This article explores trans identities, as articulated within a few historical texts. From early literary depictions of gender difference, to medicalized conceptions of transsexualism, to a proliferation of trans and queer identities represented by an ever-expanding "alphabet soup" of identity labels, our understandings of identities, sexualities, and queer community-building continue to change. I use the notion of "kind-making," as elaborated on in the work of Ian Hacking, to illustrate that some queer and trans identifications are affiliative, whereas others are contrastive or oppositional in nature, and these structural differences have important implications with respect to understanding identity and sexuality, and also trans inclusion within LGBT communities and activist efforts.

Differential effect of corn oil-based low trans structured fat on the plasma and hepatic lipid profile in an atherogenic mouse model: comparison to hydrogenated trans fat

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Kim Hye-Jin

2011-01-01

Full Text Available Abstract Background Trans fat are not desirable in many aspects on health maintenance. Low trans structured fats have been reported to be relatively more safe than trans fats. Methods We examined the effects of low trans structured fat from corn oil (LC, compared with high trans fat shortening, on cholesterol and fatty acid metabolism in apo E deficient mice which is an atherogenic animal model. The animals were fed a high trans fat (10% fat: commercial shortening (CS or a low trans fat (LC diet for 12 weeks. Results LC decreased apo B and hepatic cholesterol and triglyceride concentration compared to the CS group but significantly increased plasma total cholesterol and triglyceride concentration and fecal lipids with a simultaneous increase in HDL-cholesterol level, apo A-I, and the ratio of HDL-cholesterol to total cholesterol (HTR. Reduction of hepatic lipid levels by inclusion of LC intake was observed alongside modulation of hepatic enzyme activities related to cholesterol esterification, fatty acid metabolism and fecal lipids level compared to the CS group. The differential effects of LC intake on the plasma and hepatic lipid profile seemed to be partly due to the fatty acid composition of LC which contains higher MUFA, PUFA and SFA content as well as lower content of trans fatty acids compared to CS. Conclusions We suggest that LC may exert a dual effect on plasma and hepatic lipid metabolism in an atherogenic animal model. Accordingly, LC, supplemented at 10% in diet, had an anti-atherogenic effect on these apo E-/- mice, and increased fecal lipids, decreased hepatic steatosis, but elevated plasma lipids. Further studies are needed to verify the exact mode of action regarding the complex physiological changes and alteration in lipid metabolism caused by LC.

Differential effect of corn oil-based low trans structured fat on the plasma and hepatic lipid profile in an atherogenic mouse model: comparison to hydrogenated trans fat

Science.gov (United States)

2011-01-01

Background Trans fat are not desirable in many aspects on health maintenance. Low trans structured fats have been reported to be relatively more safe than trans fats. Methods We examined the effects of low trans structured fat from corn oil (LC), compared with high trans fat shortening, on cholesterol and fatty acid metabolism in apo E deficient mice which is an atherogenic animal model. The animals were fed a high trans fat (10% fat: commercial shortening (CS)) or a low trans fat (LC) diet for 12 weeks. Results LC decreased apo B and hepatic cholesterol and triglyceride concentration compared to the CS group but significantly increased plasma total cholesterol and triglyceride concentration and fecal lipids with a simultaneous increase in HDL-cholesterol level, apo A-I, and the ratio of HDL-cholesterol to total cholesterol (HTR). Reduction of hepatic lipid levels by inclusion of LC intake was observed alongside modulation of hepatic enzyme activities related to cholesterol esterification, fatty acid metabolism and fecal lipids level compared to the CS group. The differential effects of LC intake on the plasma and hepatic lipid profile seemed to be partly due to the fatty acid composition of LC which contains higher MUFA, PUFA and SFA content as well as lower content of trans fatty acids compared to CS. Conclusions We suggest that LC may exert a dual effect on plasma and hepatic lipid metabolism in an atherogenic animal model. Accordingly, LC, supplemented at 10% in diet, had an anti-atherogenic effect on these apo E-/- mice, and increased fecal lipids, decreased hepatic steatosis, but elevated plasma lipids. Further studies are needed to verify the exact mode of action regarding the complex physiological changes and alteration in lipid metabolism caused by LC. PMID:21247503