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Selva Onder Mithat Celebi Melda Altikatoglu Arzu Hatipoglu Huriye Kuzu 《Applied biochemistry and biotechnology》2011,163(3):433-443
This study evaluates the potential of the enzyme horseradish peroxidase in the decolorization of one common industrial azo
dye, naphthol blue black. Studies are carried out to understand the process parameters such as pH, temperature and reaction
time. The enzymatic decolorization of the dye was examined by UV-Vis spectrophotometer and LC-MS measurements. Temperature
and pH conditions were optimized for obtaining high azo-dye decolorization. Azo-dye removal at a pH range 4-6 was found to
be the highest for all temperatures. After 5 minutes of treatment, the color removal of dye was ca. 80-90%. The LC-MS and
spectrophotometric analyses indicated that the decolorization of the azo dye with enzyme was due to the reduction of the azo
bonds. This study verifies the viability of the use of the horseradish peroxidase in the decolorization of naphthol blue black. 相似文献
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Unsal M 《Physical review letters》2008,100(3):032005
We analyze the vacuum structure of SU(2) QCD with multiple massless adjoint representation fermions formulated on a small spatial S(1) x R(3). The absence of thermal fluctuations, and the fact that quantum fluctuations favor the vacuum with unbroken center symmetry in a weakly coupled regime, renders the interesting dynamics of these theories analytically calculable. Confinement and the generation of the mass gap in the gluonic sector are shown analytically. In this regime, theory exhibits confinement without continuous chiral-symmetry breaking. However, a flavor singlet chiral condensate (which breaks a discrete chiral symmetry) persists at arbitrarily small S(1). Under certain reasonable assumptions, we show that the theory exhibits a zero temperature chiral phase transition in the absence of any change in spatial center symmetry realizations. 相似文献
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Mithat Celebi Zafer Omer Ozdemir Emre Eroglu Melda Altikatoglu Ibrahim Guney 《光谱学与光谱分析》2015,(2):340-345
Synthetic dyes are very important for textile dyeing,paper printing,color photography and petroleum products.Traditional methods of dye removal include biodegradation,precipitation,adsorption,chemical degradation,photo degradation,and chemical coagulation.Dye decolorization with enzymatic reaction is an important issue for several research field(chemistry,environment)In this study,minimum decolorization time of Remazol Brilliant Blue R dye with Horseradish peroxidase enzyme was calculated using with mathematical equation depending on experimental data.Dye decolorization was determined by monitoring the absorbance decrease at the specific maximum wavelength for dye.All experiments were carried out with different initial dye concentrations of Remazol Brilliant Blue R at 25 ℃ constant temperature for 30 minutes.The development of the least squares estimators for a nonlinear model brings about complications not encountered in the case of the linear model.Decolorization times for completely removal of dye were calculated according to equation.It was shown that mathematical equation was conformed exponential curve for dye degradation. 相似文献
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Mo(CO)6 was reacted with the Schiff base ligand obtained by condensation reaction of 2‐acetyl‐ or benzoylpyridine with poly(propylene glycol)bis(2‐aminopropyl ether) to obtain polymeric, dinuclear metal tetracarbonyl compounds. The long‐chain Schiff base complexes are highly soluble even in non‐polar solvents such as petroleum ether, diethyl ether and n‐hexane. These complexes, as free‐radical initiators, afforded methyl methacrylate polymerization in chlorinated solvents. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
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Mithat Celebi Mehmet Arif Kaya Melda Altikatoglu Huseyin Yildirim 《Applied biochemistry and biotechnology》2013,171(3):716-730
In this study, covalent immobilization of the horseradish peroxidase (HRP) onto various polysulfone supports was investigated. For this purpose, different polysulfones were methacrylated with methacryloyl chloride, and then, nonwoven fabric samples were coated by using solutions of these methacrylated polysulfones. Finally, support materials were immersed into aquatic solution of HRP enzyme for covalent immobilization. Structural analysis of enzyme immobilization onto various polysulfones was confirmed with Fourier transform infrared spectroscopy, atomic force microscopy, and proton nuclear magnetic resonance spectroscopy. Decolorization of textile diazo (Acid Black 1) and anthraquinone (Reactive Blue 19) dyes was investigated by UV–visible spectrophotometer. Covalently immobilized enzyme has been used seven times in freshly prepared dye solutions through 63 days. Dye decolorization performance of the immobilized systems was observed that still remained high (70 %) after reusing three times. Enzyme activities of immobilized systems were determined and compared to free enzyme activity at different conditions (pH, temperature, thermal stability, storage stability). Enzyme activities of immobilized systems and free enzyme were also investigated at the different temperatures and effects of temperature and thermal resistance for different incubation time at 50 °C. In addition, storage activity of free and immobilized enzymes was determined at 4 °C at different incubation days. 相似文献
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An explicit expression of the high-frequency surface current excited on a perfectly conducting spherical cap by the edge-diffraction of an obliquely incident wave is derived. The result is given in the GTD terminology and shows the influence of the incidence angles on the transfer functions. To this end the real (physical) space is embedded into a twofold extended abstract space in which an equivalent canonical problem is established. This latter yields a system of dual integral equations whose kernels were not previously treated. By inverting these new kernels, the system of dual equations is reduced to two independent Wiener-Hopf problems. From the asymptotic solutions of these problems, one derives the expression of the edge-excited current along with the known geometrical optics term. The resutlt can be used directly in practical applications. If the incident ray becomes normal to the edge, then the resulting expressions are reduced to the already known expressions. The basic idea and general formulas used here can also be used to solve other diffraction problems with similar geometry. 相似文献
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An important class of electromagnetic structures involves metallic sheets on the surface of a curved dielectric interface. At high frequencies, the behavior of such structures can be analyzed by the geometrical theory of diffraction (GTD) provided that the various wave and ray species excited by a single edge are known. This problem is addressed here by determining the line source Green's function for a thin perfectly conduvting half plane wrapped around a dielectric cylinder in an infinitely extended (nonperiodic) angular space. The formally exact solution is evaluated asymptotically to yield the GTD field in various ray-optical domains, with emphasis on those wave and ray species (creeping waves, whispering gallery modes, edge scattered fields, etc.) attributed to the presence of the edge. When the dielectric contrast is reduced to zero, all expressions are found to agree with those known for a curved sheet in a homogeneous medium. 相似文献
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Hakan Pekey Mithat Bakoğlu Beyhan Pekey 《International journal of environmental analytical chemistry》2013,93(14):1025-1036
The study aimed to examine source apportionment of heavy metals of the surface sediments in the <63?µm size fraction. The sediment samples collected from 34 sites at the Western Bay of Izmit were subjected to a total digestion technique and analysed for major (total organic carbon, Al, Fe, Mg, and S) and trace (As, Cd, Co, Cr, Cu, Mn, Ni, Pb, Sn, V, and Zn) elements by inductively coupled plasma-atomic emission spectrometry. The results were compared with the marine sediment quality standards, as well as literature values reported to assess the pollution status of the sediments. A factor analysis/multiple regression (FA/MR) multivariate receptor modelling technique was used for quantitative source apportionment to estimate the contributions from each source of contamination. Source fingerprints were obtained from the literature. A varimax rotated factor analysis was applied to the whole data set, and four probable source types were identified as the iron and steel industry, paint industry, crustal and sewage for heavy metals, explaining about 84% of the total variance. Source apportionment results derived from the FA and FA/MR methods agree well with each other. 相似文献
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