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In this study the simple rapid method for the preparation of benzimidazole and benzothiazole by the condensationof an o-phenylene diamine with the aromatic aldehyde in presence of the ZnS nanoparticles derived from Trigonella foenum-graecum. Plant. ZnS as a catalyst was prepared by using the waste stem of the Trigonella foenum-graecum plant. The preparation of benzimidazole and benzothiazole derivative reaction carried under the mild condition with very high excellent yield. The method is used with aromatic, unsaturated and hetroaromatic aldehyde. the main advantage of this method as a very short reaction time, solvent-free reaction condition, reusable catalyst, milder reaction, easy workup, a waste stem of the plant was used. [ABSTRACT FROM AUTHOR]

Present work describes the synthesis and characterization of a Schiff base N-Benzylidene-N'-pyridin-4-ylmethylene-benzene-1,4-diamine and its reduced form N-Benzyl-N'-pyridin-4-ylmethyl-benzene-1,4-diamine (R1). Reduced Schiff base N-Benzyl-N'-pyridin-4-ylmethyl-benzene-1,4-diamine (R1) is documented to be colorimetric and fluorometric chemosensor for fluoride anions. R1 binds F-selectively with a large binding constant (3.49 x 105). [ABSTRACT FROM AUTHOR]

The benzimidazole derivatives (1-9) were prepared from the reaction of the compound 4-methylorthophenylenediamine with two moles of different aldehydes when ammonium chloride is used as a catalyst, using a home microwave device. The prepared compounds were diagnosed using the infrared spectrum (FT-IR) and the proton nuclear magnetic resonance (1H-NMR1) spectrum, and thin layer chromatography (TLC) was used to follow the course of the reactions. The effect of some prepared compounds on the growth of one type of fungi was studied. The yeast class is Candida and a type of bacterial isolate from the class Bacillus is Bacillus Puimilus, and the standard anti-fungi (Nystatin) and the standard antibiotic (neomycin sulfate) for bacteria were used, and the results indicate that the synthesized compounds have the ability to inhibit against the fungi and bacteria. [ABSTRACT FROM AUTHOR]

The influence of the solvent nature on the direction of the aminoalkylation reaction of asymmetric diamines under the conditions of basic catalysis is studied. A general mechanism of the process is proposed, including intermediate stages of formation of two types of quaternary ammonium centers (QAC), which have different reactivity in the subsequent stage of destruction. It is established that the ratio of the yields of the final reaction products, secondary triamines and triamines with a quaternary nitrogen atom, is determined by the degree of stabilizing effect of the solvent on the reaction center of QAC of different structures R1R2R3N+ and R1R2HN+. [ABSTRACT FROM AUTHOR]

A simple and efficient microwave irradiated synthesis of bis(α-aminophosphonates) has been developed by the reaction of 1,2-diphenylethane-1,2-diamine, aromatic aldehydes, and dimethyl phosphite in the presence of calcium bromide as catalyst under neat conditions at room temperature. All the title compounds were screened for their anticoagulant activity using blockasol as standard. The compounds containing thio group exhibited promising anticoagulant activity when compared to blockasol. [ABSTRACT FROM AUTHOR]

The biaxial stretching film of polyamide 6 (PA6) is widely used for food and industrial products packaging, because it has good physical properties, such as high toughness and gas barrier properties. It is expected to improve film formability and performance for a larger market. So, in this research, both the stretching methods and PA6 blends were investigated in terms of dynamics and structure development for biaxial stretching films. There are three different stretching methods which can produce polyamide 6 films, namely the simultaneous biaxial stretching, the sequential biaxial stretching, and the double bubble tubular process. There are no reports which describe the difference among the three stretching methods and film properties, so it was not clarified why the films have big differences in their properties. For this reason, the higher order structure and stretching behaviours of the three stretching methods were studied. As a result, the sequential biaxial stretching shows strong stretched effect and molecular orientation in the transverse direction. In the simultaneous biaxial stretching, the molecule orientation was equal both in the machine direction and in the transverse direction of the stretched plane. The double bubble tubular process produced well balanced film and equal orientation in any directions, in terms of the phase difference in the plane of film. Blends of PA6 to meta-Xylene diamine (MXD6) improved the properties of easy straight line cut and high barrier, but did not have good stretchability. For this reason, they were also studied to develop the biaxial stretching film of polyamide which improved stretchability and physical properties. Furthermore, blend effects of MXD6 to PA6 and dynamics analyses were investigated. [ABSTRACT FROM AUTHOR]

Insoluble fullerene-diamine adduct thin-films consisting of C60 and 1,2-diaminoethane were easily fabricated on an electrode by an alternate immersion process. Formation of the C60-diamine adduct films were confirmed using transmission absorption spectroscopy and atomic force microscopy. An inverted-type organic solar cells were fabricated by using the C60-diamine adduct film as the electron transport layer. The resultant photoelectric conversation performance of the solar cells suggested that photocurrent is generated via the photoexcitation of polythiophene. The result suggests that the present insoluble fullerene-diamine adduct films worked as buffer layer for organic thin-film solar cells. [ABSTRACT FROM AUTHOR]

Insoluble fullerene-diamine adduct thin-films consisting of C60 and 1,2-diaminoethane were easily fabricated on an electrode by an alternate immersion process. Formation of the C60-diamine adduct films were confirmed using transmission absorption spectroscopy and atomic force microscopy. An inverted-type organic solar cells were fabricated by using the C60-diamine adduct film as the electron transport layer. The resultant photoelectric conversation performance of the solar cells suggested that photocurrent is generated via the photoexcitation of polythiophene. The result suggests that the present insoluble fullerene-diamine adduct films worked as buffer layer for organic thin-film solar cells. [ABSTRACT FROM AUTHOR]

Renewable alternatives to petroleum derived thermosetting polymers have elicited increasing interest due to potential positive economic and ecological impacts. New materials should mimic the rigid phenyl structures of high-performance commercial thermosetting resins. Furans derived from cellulose and hemicellulose are promising candidates for replacing phenyl incumbents, and a direct property comparison of thermosetting polymers prepared using furanyl and phenyl diepoxy monomers is warranted. In this work, thermosetting polymers were prepared using furanyl and phenyl diepoxy monomer analogs cured with a cycloaliphatic diamine hardener, 4, 4'-methylene biscyclohexanamine. The structure-property study shows that furanyl-based polymers possess superior mechanical properties and high-temperature char yield compared with their phenyl analogs. An epoxy-amine cure kinetics study highlights differences in cure behavior that could be responsible for the superior mechanical characteristics of furanyl-based polymers. [ABSTRACT FROM AUTHOR]

Bio-functionalization or surface modification is an important technique to obtain biocompatibility in semiconductor nanoparticles for biomedical applications. In this study semiconductor core/shell quantum dots of CdSe/ZnS have been prepared by chemical reduction method and then further PEGylated using Poly(ethylene glycol) diamine of Mw 2000. They were characterized by UV-vis spectroscopy & Fourier transform infrared spectroscopy. The results reveals the successful PEGylation of CdSe/ZnS quantum dots. [ABSTRACT FROM AUTHOR]

'SimOLED' simulator is used in this work to investigate the efficiency of the mixed-host organic light emitting devices (MH-OLEDs). Tris-(8-hydroxyquinoline) aluminum(3) (Alq3) and N,N-diphenyl-N,N-Bis(3-methylphenyl)-1,1-diphenyl-4,4-diamine (TPD) are used as the electron transport layer (ETL) material and hole transport layer (HTL) material respectively, and the indium-doped tin oxide (ITO) and aluminum (Al) as anode and cathode. Three MH-OLEDs, A, B and C with the same structure of ITO/HTM (15 nm)/Mixed host (70 nm)/ETM (10 nm)/Al, are stimulated with ratios TPD:Alq3 of 3:5, 5:5, and 5:3 respectively. The Poole-Frenkel model for electron and hole mobilities is employed to compute the current density-applied voltage-luminance characteristics, distribution of the electric field, carrier concentrations and recombination rate. [ABSTRACT FROM AUTHOR]

Based on experimental and theoretical research during the last decade, giant optical nonlinearities found in Mott-Hubbard insulators like Sr2CuO3,Ca2CuO3, Nickel halides ([Ni(chxn)2X]X2 where X = Br, Cl and 'chxn' refers to cyclohexanediamine) are presented. These materials are reported to be potential materials for all optical switching devices. The occurrence of nearly degenerate lowest one- and two-photon states, strong Coulomb correlation and strong dipole coupling between the one- and two-photon states are believed to be the reason for such colossal optical nonlinearities in these systems. In some of these materials (at least), the two photon state is below the one-photon state. This leads to the possibility that such material can be excited to the lowest optical state by shinning laser of suitable wavelength, the populations thus generated decays to the two-photon state at ultrafast short time. Thus nonlinear measurements can be made from an excited state (we call as excited state nonlinear optical properties). One dimensional strongly correlated materials are predicted to have several orders-of-magnitude larger excited state optical non-linearities in comparison to that from the ground state, in the wavelength region suitable for terahertz communications. A large number of measurable nonlinear optical properties like Two Photon absorption, Photo induced absorption, Third Harmonic generation, Stimulated Raman Scattering are obtained theoretically and compared with available experimental observations. Then a large number excited state nonlinear optical properties are predicted which are experimentally measurable. We emphasize that the mechanism of nonlinear optics in one dimensional Mott-Hubbard insulators is different from that of the π-conjugated polymers - in the former spin excitation play an important role. We argue from detailed understanding of nonlinear optics of π-conjugated systems that some features in the Third Harmonic Generation susceptibility measurements are perhaps finger print of gapless spin excitations of Mott-Hubbard insulators. [ABSTRACT FROM AUTHOR]

In this paper, Ibuprofen, a water insoluble drug was covalently attached to PEGylated nanoparticles. Firstly, Surface functionalization of water dispersed core/shell nanoparticles had been done using hydrophilic polymer PEG-diamine. Therefore, PEGylated nanoparticles contain NH2 groups over the surface of nanoparticles and can be used for the further attachment of biomolecules. Ibuprofen was covalently loaded on the PEGylated core/shell nanoparticles using carbodiimide reaction. The synthesis had been carried out under two different pH environments, as the solubility of Ibuprofen is pH dependent. The resultant samples were characterized using UV-Vis absorption and FT-IR spectroscopy. The results strongly suggest the successful chemical conjugation of Ibuprofen to PEGylated nanoparticles in aqueous media and they could be further used for drug delivery applications. [ABSTRACT FROM AUTHOR]