Effect of Functionalized Magnetite Nanoparticles and Diaminoxanthone on the Curing,Thermal Degradation Kinetic and Corrosion Property of Diglycidyl Ether of Bisphenol A-Based Epoxy Resin

To prepare a high-performance epoxy resin with excellent thermal, chemical and corrosion stability, diaminoxanthone（DAX） was used to cure diglycidylether of bisphenol-A（DGEBA）-based epoxy resin and blend of DGEBA with functionalized Fe3O4 nanoparticles. Kinetic parameters of curing and thermal degradation of epoxy resin systems were estimated by differential scanning calorimetry（DSC） and thermogravimetric analysis（TGA）, respectively. The 10% weight loss temperature has been increased from 340 °C to 366 °C and there was an increase in the char yield from 32.6% to 45.3% for the above systems. The corrosion performance of epoxy coated carbon steel was examined by potentiodynamic polarization, along with immersion test in 1.0 mol/L HCl solution. The results showed that epoxy resins cured with DAX had low tendency to corrosion. In addition, the cured epoxy resin containing 10% Fe3O4 had higher anticorrosion activity than bare DGEBA system. The results showed that functionalized Fe3O4 nanoparticles enhanced char formation and improved the thermal stability as well as anticorrosion activity of the resin.     

Crystallization of polylactic acid under in situ deformation during nonsolvent‐induced phase separation

In this study, we investigate polylactic acid (PLA) crystallization under in situ biaxial extension in a nonsolvent‐induced phase separation foaming process. Our ternary system consists of PLA, dichloromethane (DCM) as solvent and hexane as nonsolvent. For the first time, the formation of a shish‐kebab crystalline morphology is observed in such a solution‐based foaming process in certain solid–liquid phase separated systems. The formation of shish‐kebabs is described based on the coil‐stretch transition concept. The rapid biaxial deformation caused by macropore growth uniaxially stretches the long chains that are tied with at least two single crystals which eventually leads to the formation of shish structures throughout the polymer‐rich phase. The kebab lamellae then form perpendicularly on the shish cores. The scanning electron microscopy (SEM) observations and our interpretation of the crystallization phenomena are confirmed by differential scanning calorimetry (DSC) analysis. The observation of various crystalline morphologies, particularly shish‐kebabs, and the elucidation of their formation mechanisms contribute to the understanding of phase separation and pore growth as well as crystallization in such polymer–solvent–nonsolvent systems. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2017 , 55, 1055–1062     

Synthesis,crystal structure,antibacterial, cytotoxic,and anticancer activities of new Pd(II) complexes of tri-p-tolyl phosphine with thiones

Russian Journal of General Chemistry - Four Pd(II) complexes of general formula [Pd(L1)2(L2)2], where L1 = pyridine-2(1H)-thione, pyrimidine-2(1H)-thione, pyridine-4(1H)-thione, and...     

A novel construction of substitution box using a combination of chaotic maps with improved chaotic range

The influential application of substitution boxes in secure communication and multimedia security attracted researchers to construct more robust substitution boxes. The advantage of using chaos in the secure communication is to get additional unpredictability and randomness in data. In this paper, substitution boxes are constructed with the help of chaotic system and linear fractional transformation. The 256 distinct values of each substitution box are then checked with the help of different available algebraic and statistical analyses. These tests evaluate the strength and application of substitution boxes in different encryption techniques. The results indicate the strength of anticipated technique.

     

Visible light induced catalytic properties of CdSe-graphene nanocomposites and study of its bactericidal effect

A novel composite, CdSe-graphene, was synthesized using facile hydrothermal method. The structural characteristics studies of the synthesized composites were investigated by X-ray diffraction （XRD）, scanning electron microscope （SEM）, transmission electron microscope （TEM）, Brunauer, Emmett, Teller specific surface area （BET） and X-ray photoelectron spectroscopy （XPS）. The photocatalytic activity was investigated by the degradation of methylene blue as standard dye. The degradation of M8 was calculated based on the decrease in concentration of the dye with respect to regular time intervals. The reusability tests were done to investigate the stability of the used catalysts. Additionally the antibacterial activity of CdSe-graphene was also investigated using bacterium Streptococcus aureus （S. aureus）.