Synthesis and X-ray structure analysis of benzoic acid [1-(6-methyl-2,4-dioxo-3,4-dihydro-2H-pyran-3-yl)eth-(E)-ylidene]-hydrazide with a water molecule (C15H14N2O4?H2O)

The crystal structure of the title compound has been determined by X-ray diffraction methods. It crystallizes in the monoclinic space group P2₁/n with cell parameters a = 7.097(1) Å, b = 19.257(1) Å, c = 10.893(1) Å, = 106.17(2), V = 1429.8(3) ų and Z = 4. The final reliability index is 0.059 for 2419 observed reflections. The molecule comprises of two six- membered rings which are abridged together through a network of C–N, N–N and C–N bonds. There are three keto functional groups and two methyl groups at various locations of the molecule. The C9 atom of methyl group and O2 of the keto group are deviated significantly from the mean plane of the molecule. Both the six-membered rings are planar and it is evident from the magnitude of their exocyclic torsion angles. The molecular structure is stabilized by few intra and intermolecular hydrogen bonds.     

Blind and Secured Adaptive Digital Image Watermarking Approach for High Imperceptibility and Robustness

In the past decade, rapid development in digital communication has led to prevalent use of digital images. More importantly, confidentiality issues have also come up recently due to the increase in digital image transmission across the Internet. Therefore, it is necessary to provide high imperceptibility and security to digitally transmitted images. In this paper, a novel blind digital image watermarking scheme is introduced tackling secured transmission of digital images, which provides a higher quality regarding both imperceptibility and robustness parameters. A block based hybrid IWT- SVD transform is implemented for robust transmission of digital images. To ensure high watermark security, the watermark is encrypted using a Pseudo random key which is generated adaptively from cover and watermark images. An encrypted watermark is embedded in randomly selected low entropy blocks to increase the security as well as imperceptibility. Embedding positions within the block are identified adaptively using a Blum–Blum–Shub Pseudo random generator. To ensure higher visual quality, Initial Scaling Factor (ISF) is chosen adaptively from a cover image using image range characteristics. ISF can be optimized using Nature Inspired Optimization (NIO) techniques for higher imperceptibility and robustness. Specifically, the ISF parameter is optimized by using three well-known and novel NIO-based algorithms such as Genetic Algorithms (GA), Artificial Bee Colony (ABC), and Firefly Optimization algorithm. Experiments were conducted for the proposed scheme in terms of imperceptibility, robustness, security, embedding rate, and computational time. Experimental results support higher effectiveness of the proposed scheme. Furthermore, performance comparison has been done with some of the existing state-of-the-art schemes which substantiates the improved performance of the proposed scheme.     

Solvation thermodynamics of xylitol in water and in aqueous amino acids at 298.15 K

The scaled particle theory has been applied to calculate the free energy, ΔG_solv, enthalpy, ΔH_solv, and entropy, ΔS_solv of solvation for xylitol in water and in aqueous amino acids (glycine, alanine and valine) at 298.15 K. The solvation energy, enthalpy and entropy of xylitol are expressed in terms of their various ingredients. The results show that the interaction terms contribute favorably to the process of solvation. The results suggest that the cavity formation for accommodation of xylitol molecules in aqueous amino acids is an enthalpy‐dominated process. Furthermore, the investigated parameters indicate that xylitol–amino acid interactions follow the sequence: glycine alanine valine water. The findings of the present work may help to throw light on the role that xylitol can play to stabilize macromolecules like proteins in aqueous solutions. Copyright © 2012 John Wiley & Sons, Ltd.     

Synthesis and Electroluminescence properties of Tris [ 5-choloro- 8- hydroxyquinoline] Aluminium Al(5-Clq)3

A new electroluminescent material tris-[5-choloro-8-hydroxyquinoline] aluminum has been synthesized and characterized. Solution of this material Al(5-Clq)₃ in toluene showed absorption maxima at 385 nm which was attributed to the moderate energy (π-π^*) transitions of the aromatic rings. The photoluminescence spectrum of Al(5-Clq)₃ in toluene solution showed a peak at 522 nm. This material shows thermal stability up to 400 ℃. The structure of the device is ITO/0.4 wt%F4-TCNQ doped α-NPD (35 nm) / Al(5-Clq)₃(30 nm)/ BCP (6 nm)/ Alq₃(30 nm)/ LiF (1 nm)/Al(150 nm). This device exhibited a luminescence peak at 585 nm (CIE coordinates, x= 0.39, y= 0.50). The maximum luminescence of the device was 920 Cd/m² at 25 V. The maximum current efficiency of OLED was 0.27 Cd/A at 20 V and maximum power efficiency was 0.04 lm/W at 18 V.     

用于吖内酯合成的二氧化钛纳米晶体材料PriyankaAnandgaonker,GaneshKulkarni,SureshGaikwad,AnjaliRajbhoj简

Titanium dioxide nanoparticles were prepared by a electrochemical reduction method using parameters such as current density, solvent polarity, distance between electrodes, and concentration of stabilizers to control the size of the nanoparticles. The nanoparticles were characterized by UV-Vis spectroscopy, X-ray diffraction, scanning electron microscopy and transmission electron microscopy, and their catalytic performance was tested for the synthesis of a series of 4-aryldiene-2-phenyl-5(4)-oxazolones from the cyclodehydration and condensation of the respective aldehyde, hippuric acid and acetic anhydride. Easy availability, reusability and eco-friendliness were some prominent features of the nanocrystalline titanium dioxide catalyst.     

Outcoupling efficiency enhancement in organic light emitting diodes via nano-structured indium tin oxide and nano-phosphors

Nanostructures of indium tin oxide (NSITO) deposited using glancing angle deposition (GLAD) technique are used to enhance the outcoupling efficiency of blue and green OLEDs. The enhancement was found to be angle independent. The efficiency of device has increased by about 2.1 times by the use of NSITO at glass/air interface and ITO/glass interface. Similarly nano-phosphor particles were used to recover the glass modes by depositing them on the backside of the substrates. Both these methods were found to be effective for outcoupling efficiency enhancement.     

Synthesis of TiO2 nanoparticles by electrochemical method and their antibacterial application

Titanium dioxide nanoparticles were successfully prepared by electrochemical method. The tetra propyl ammonium bromide salt was used as stabilizing agent in an organic medium viz. tetra hydro furan (THF) and acetonitrile (ACN) in 4:1 ratio by optimizing current density. The parameters such as current density, solvent polarity, distance between electrodes and concentration of stabilizers were used to control the size of nanoparticles. The synthesized titanium dioxide nanoparticles were characterized by using UV–Visible spectroscopy, X-ray diffraction, scanning electron microscopy (SEM), energy dispersive spectrophotometer (EDS) and transmission electron microscopy (TEM) analysis techniques. TEM analysis proved a nearly tetragonal structure with size of 25–30 nm which was in agreement with the result calculated from the XRD analysis. EDS analysis revealed the presence of Ti and O element. The nanoparticles were screened for their in vitro antibacterial activity against human pathogens such as gram negative Escherichia coli (E. coli), and gram positive Staphylococcus aureus strains and which proved excellent results.     

Norm inequalities related to the matrix geometric mean

Inequalities for norms of different versions of the geometric mean of two positive definite matrices are presented.