Synthesis, spectral, thermal and biological studies of Co(III) and binuclear Ni(II) complexes with a novel amine-imine-oxime ligand

Two different metal complexes of [Co(HL)(L)(Ac)₂]·4H₂O (I) and [Ni₂(L)₂(Ac)₂]·4H₂O (II), have been synthesized with newly prepared amine-imine-oxime ligand [HL = 3-(4′-aminobiphenyl-4-ylimino)-butan-2-one oxime, Ac = CH₃COO⁻]. This ligand HL was prepared by the condensation of diacetylmonoxime with benzidine. The structure of the ligand and complexes have been proposed by elemental analyses, IR, ¹H, and ¹³C NMR, electronic spectra, magnetic susceptibility measurements, mass spectra, molar conductivity and thermo gravimetric analysis. The molar conductance measurements of the complexes in DMF solution correspond to non electrolytic nature for the complexes. Octahedral and tetrahedral geometries have been determined to the complexes of Co(III) and binuclear Ni(II) respectively. The ligand and its metal complexes were tested in vitro for their biological effects. Their activities against two gram-positive (Bacillus subtilis and Staphylococcus aureus) and one fungal specie (Candida albicans) were found. They were inactive against tested gram negative bacteria. The text was submitted by authors in English.     

Synthesis of cationic N‐[3‐(dimethylamino)propyl]methacrylamide brushes on silicon wafer via surface‐initiated RAFT polymerization

Surface‐initiated reversible addition‐fragmentation chain transfer (SI‐RAFT) polymerization of N‐[3‐(dimethylamino)propyl]methacrylamide (DMAPMA) on the silicon wafer was conducted in attempt to create controllable cationic polymer films. The RAFT agent‐immobilized substrate was prepared by the silanization of hydroxyl groups on silicon wafer with 3‐aminopropylthriethoxysilane (APTS) and by the amide reaction of amine groups of APTS with ester groups of 4‐cyano‐4‐((thiobenzoyl) sulfanyl) pentanoic succinimide ester (CPSE); followed by the RAFT polymerization of DMAPMA using a “free” RAFT agent, that is, 4‐cyanopentanoic acid dithiobenzoate (CPAD) and an initiator, that is, 4,4′‐azobis‐4‐cyanopentanoic acid (CPA). The formation of homogeneous tethered poly(N‐[3‐(dimethylamino)propyl]methacrylamide) [poly(DMAPMA)] brushes, whose thickness can be tuned by reaction time varying, is evidenced by using the combination of grazing angle attenuated total reflectance‐Fourier transform infrared spectroscopy, X‐ray photoelectron spectroscopy, atomic force microscopy, and water contact‐angle measurements. The calculation of grafting parameters from the number‐average molecular weight, M _n (g/mol) and ellipsometric thickness, h (nm) values indicated the synthesis of densely grafted poly(DMAPMA) films and allowed us to predict a polymerization time for forming a “brush‐like” conformation for the chains. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011     

Determination of K shell fluorescence cross-section and Kβ/Kα intensity ratios for Fe,Se, Te,FeSe, FeTe and TeSe

The fluorescence cross-sections (σ_Ki) and the intensity ratios K_β/K_α for pure Fe, Se, Te elements and FeSe, FeTe, TeSe complexes have been investigated. The samples were excited by 59.5 keV γ-rays from ²⁴¹Am annular radioactive source and emitted X-rays. They were counted by an Ultra-LEGe detector with resolution of 150 eV at 5.9 keV. For pure elements results have been compared with the theoretical calculated values. According to our results band length and mutual interaction of atoms affected the results. We claimed that these effects would help researchers who study on superconductors, especially determining which compound can be show the superconductor properties.     

A theory of high frequency vibrations of piezoelectric cyrstal bars

This paper presents a higher order, linear theory of piezoelectric crystal bars as in the same spirit as that of Mindlin. First, a power series representation in aerial coordinates is employed for both the mechanical displacement and electric potential fields. Next, with the help of a variational theorem deduced from Hamilton's principle, together with these series, the theory is established consistently. A hierarchy of 1-dimensional approximate equations of motion, charge equations of electrostatics, initial and boundary conditions, strain-displacement and electric field-electric potential relations, and macroscopic constitutive equations constitutes the theory, and it governs all the types of motions of piezoelectric crystal bars of uniform cross-section. Further, special cases of interest are pointed out. The solutions of the initial mixed boundary-value problems defined by this theory are proven to be unique.     

X-ray structure of {[μ-N,N′-Bis(salicylidene)-1, 3-propane-diamine] (dimethylformamide) zinc(II)} dibromo cadmium(ii)

The title compound, forms crystals which are the orthorhombic system, space group P2 ₁2₁2₁, with unit cell dimensions a = 10.3928(12) Å, b = 14.6298(13) Å, c = 15.9514(11) Å, V = 2425.3(4) ų. The cell contains four molecules. The structure is a heteronuclear dimeric complex with Zn^II and Cd^II ions. The coordination around the Zn^II ion is distorted square–pyramid and the Cd^II ion is distorted tetrahedral coordination. The Zn·sCd distance is 3.3594(7) Å.     

Deconvolution of continuous internal bremsstrahlung spectra of 32P, 85Kr and 143Pr

An efficient method of deconvolution of the internal bremsstrahlung (IB) spectra accompanying the β‐decay in ³²P, ⁸⁵Kr and ¹⁴³Pr is presented. Experimental data is taken from the literature. The usual experimental values are folded with the response matrix of the detector system, and the Gold iteration technique is employed to deconvolve the detector response function for the continuous IB photon spectra. The response function of the detector is calculated using the peak to total ratio and the energy resolution of the detector. The results of the deconvolved IB spectra along with the theoretical calculations are presented. Copyright © 2007 John Wiley & Sons, Ltd.     

Crystal structure of [2,6-bis(3,5-dimethyl-N-pyrazolyl)pyridine]-(azido)(chloro)copper(II).

In the title compound, the coordination around the Cu atom is a distorted square-pyramid involving three N atoms from the ligand and one N atom from the azido group at the basal plane. The Cl atom is located at the apical position. The Cu atom is 0.32(5)A above the basal plane. There are three intramolecular and four weak intermolecular hydrogen bonds in the structure. IR spectra confirm the asymmetric N3 stretching vibrations of the terminal azide group.     

Copolymers of 2‐[(5‐Methylisoxazol‐3‐yl)amino]‐2‐oxo‐ethyl Methacrylate with Ethyl Methacrylate: Monomer Reactivity Ratios,Thermal Properties and Antimicrobial Activity

We report the monomer reactivity ratios for copolymers of ethyl methacrylate (EMA) and a reactive monomer, 2‐[(5‐methylisoxazol‐3‐yl)amino]‐2‐oxo‐ethyl methacrylate (IAOEMA), using the Fineman‐Ross, Kelen‐Tüdös, and a nonlinear error invariable model method using a computer program RREVM. Copolymers were obtained by radical polymerization initiated by α,α'‐azobisisobutyronitrile in 1,4‐dioxane solution and were analyzed by FTIR, ¹H‐NMR, and gel permeation chromatography. Elemental analysis was used to determine the molar fractions of EMA and IAOEMA in the copolymers. The reactivity ratios indicated a tendency toward ideal copolymerization. The polydispersity indices of the polymers determined using gel permeation chromatography suggest a strong tendency for chain termination by disproportionation. Thermal behaviors of copolymers with various compositions were investigated by differential scanning calorimetry and thermogravimetric analysis. It was observed that glass transition temperature of copolymers increased with increasing of IAOEMA content in copolymers. Also, the apparent thermal decomposition activation energies (ΔE_d) were calculated by Ozawa method using the SETARAM Labsys TGA thermobalance. The homo‐ and copolymers were tested for their antimicrobial properties against selected microorganisms. All the products show moderate activity against different strains of bacteria, fungi and yeast.     

Use of silane coupling agents to improve epoxy-rubber interface

Scrap car tyre particles can be used as filler or toughening agent in rigid epoxy matrices if the resultant interface is adequate. The objective of this work was to investigate the effects of use of different silane coupling agents (SCAs) to improve the interface between the epoxy resin and recycled rubber particles. For this purpose, seven different SCA were used to modify surfaces of the rubber particles. After the preparation of epoxy-rubber specimens, tensile Charpy impact and plane-strain fracture toughness tests were conducted. Mechanical tests and fractographic studies revealed that some of the SCA can improve of the interface between the epoxy matrix and the rubber particles leading to increases in strength while slight decreases in toughness of the samples.