This work describes the enhancement of phenol red decolorization through immobilizing of laccase in chitosan and enzyme recycling. Commercial laccase from white rot fungus, Trametesversicolor (Tvlac), was immobilizedin to freshly prepared chitosan beads by using glutaraldehyde as a cross linker. Characterization of prepared chitosan was confirmed by FTIR and scanning electron microscope (SEM). Tvlac (46.2 U/mL) immobilized into chitosan beads at 0.8 % glutaraldehyde (v/v) within 24 hrs. Synthetic (HBT) and natural (vanillin) mediators were used to enhance dye decolorizoation. It was found that 89 % of phenol red was decolorized by chitosan beads within 180 min. in the absence of enzyme and mediator, while decolorization percentage of the dye was completed (100%) at 120 min. when chitosan immobilizedlaccase was applied. Moreover, the decolorization was completed within 25 and 50 min. in the presence of chitosan immobilized laccase and of HBT or vanillin respectively. On the other hand, the recycling of chitosan immobilized laccase was still decolorize phenol red and continued up to ninth cycle to reach 70% of dye decolorization .
In this research, some robust non-parametric methods were used to estimate the semi-parametric regression model, and then these methods were compared using the MSE comparison criterion, different sample sizes, levels of variance, pollution rates, and three different models were used. These methods are S-LLS S-Estimation -local smoothing, (M-LLS)M- Estimation -local smoothing, (S-NW) S-Estimation-NadaryaWatson Smoothing, and (M-NW) M-Estimation-Nadarya-Watson Smoothing.
The results in the first model proved that the (S-LLS) method was the best in the case of large sample sizes, and small sample sizes showed that the
... Show MoreIndium Antimonide (InSb) thin films were grown onto well cleaned glass substrates at substrate temperatures (473 K) by flash evaporation. X-ray diffraction studies confirm the polycrystalline of the films and the films show preferential orientation along the (111) plane .The particle size increases with the increase of annealing time .The transmission spectra of prepared samples were found to be in the range (400-5000 cm-1 ) from FTIR study . This indicates that the crystallinity is improved in the films deposited at higher annealing time.
This study examines the monthly mean diurnal variations of the ionospheric sporadic E (Es) layer’s critical frequency (
Abstract: The use of indirect, all-ceramic restorations has grown in popularity among dentists. Studies have demonstrated that for indirect ceramic restorations to be effective over time, cement and ceramic must be bonded in a stable manner. Chemical, mechanical, and laser irradiation are among the methods used to precondition ceramic surfaces in order to increase bond strength.The objective of the study: This study was performed to investigate the roughness values and surface topography of lithium disilicate glass-ceramic treated with conventional methods and different Er,Cr:YSGG, and fractional CO2 laser conditioning parameters.Material and methods:<
... Show MoreThe Hubble telescope is characterized by the accuracy of the image formed in it, as a result of the fact that the surrounding environment is free of optical pollutants. Such as atmospheric gases and dust, in addition to light pollution emanating from industrial and natural light sources on the earth's surface. The Hubble telescope has a relatively large objective lens that provides appropriate light to enter the telescope to get a good image. Because of the nature of astronomical observation, which requires sufficient light intensity emanating from celestial objects (galaxies, stars, planets, etc.). The Hubble telescope is classified as type of the Cassegrain reflecting telescopes, which gives it the advantage of eliminating chromat
... Show MoreChina is moving towards building the largest economic power in the world, so what does this mean economically and politically for Europe, America, the Middle East and the Arab world? This project is called the expansionist Chinese Marshall Plan which is a revival of the old Silk Road in a new way. It represents the aspirations of the Chinese people and their president, Xi Jinping, to build a transport route from Asia to Europe and a railway plan to transport goods. The purpose of this is to develop the economic growth model, expand into new markets, promote the Chinese currency, and expand economic and political influence in the areas covered by the Chinese initiative. Equal opportunities in distributing investments to these countries, a
... Show MorePyridine-2, 6-dicarbohydrazide comp (2) was synthesized from ethanolic solution of diethyl pyridine-2, 6- dicarboxylate comp (1) with excess of hydrazine hydrate. Newly five polymers (P1-P5) were synthesized from reaction of pyridine-2, 6-dicarbohydrazide comp (2) with five different di carboxylic acid in the presence of poly phosphoric acid (PPA). The antibacterial activity of the synthesized polymers was screened against some gram positive and gram negative bacteria. Antifungal activity of these polymers was evaluated in vitro against some yeast like fungi such as albicans (candida albicans). Polymers P3, P4 and P5 exhibited highest antibacterial and antifungal against all microorganisms under test.