Densities ρ and viscosities η for several concentrations of amino acids (Serine, Cysteine and Threonine) at different temperatures (298.15, 303.15 and 308.15K) have been measured. On the basis of these data, the apparent molal volumes v , partial molal volumes at infinite dilution v , slope Sv , Gibbs free energy of activation for viscous flow of solution ∆G1,2 and Jones – Dole Bcoefficients were calculated the nature of solute-solvent and solute-solute interactions have been discussed in terms of the values of v , v , Sv and B-coefficents

Background: The PMMA polymer denture base materials are low mechanical properties, adaptation of the denture base to underlying tissue is important for retention and stability of denture. The aim of the study was toevaluate the effect of mixtureZrO2-Al2O3 nanoparticles on impact strength, transverse strength, hardness, roughness, denture base adaptation of heat cured acrylic resin denture base material. Materials and methods: One hundred (100) specimens were prepared, the specimens were divided into five groups (20 specimens to each) according to the test type, each group was subdivided in to two subgroups (control and experimental) each subgroup consist of 10 specimens, the experimental group included mixture of 2% (ZrO2-Al2O3ratio2:1) b

In this work lactone (1) was prepared from the reaction of p-nitro phenyl hydrazine with ethylacetoacetate, which upon treatment with benzoyl chloride afforded the lactame (2). The reaction of (2) with 2-amino phenol produced a new Schiff base (L) in good yield. Complexes of V(IV), Zr(IV), Rh(III), Pd(II), Cd(II) and Hg(II) with the new Schiff base (L) have been prepared. The compounds (1, 2) were characterized by FT-IR and UV spectroscopy, as well as characterizing ligand (L) by the same techniques with elemental analysis (C.H.N) and (1H-NMR). The prepared complexes were identified and their structural geometries were suggested by using elemental analysis (C.H.N), flame atomic absorption technique, FT-IR and UV-Vis spectroscopy, in additio

Inthis study new derivatives of Schiff bases and nucleoside analogues have been synthesized from the starting material D-glucose after a series of reactions. Derivative 1 was prepared from D-glucose then react with P-bromoacetophenone gave derivative 2 was reacted with dimethyl sulfoxide and acetic anhydride for dehydration a molecule of water gave 3. The spiro ring was prepared at 3-position from the reaction of 3 derivative with 1-phenyl-2–thioureagave 4. The protection group at 1 position was removed by using acetic acid fllowed by periodate oxidation to obtain 6. Reaction of 6 with hydrazide derivative at once and dtriazole derivative at another gave 8 and 9 respectively. Compound 6 was reduced to gave derivative 7. The 1-hydroxylgrou

Sulfamethoxazole (SMX) is the most significant antibiotic in the sulfonamide family. It was chosen as the representative of this category because of its widespread use. Starting with sulfamethoxazole, a new series of 2-Azetidinone (M1-M6) was synthesized, the structure of these new derivatives was confirmed using spectral methods, starting with the synthesis of Schiff’s bases by reflux of different aromatic benzaldehydes, separately, with Sulfamethoxazole in ethanol with few drops of acetic acid. The final compounds were obtained by ketene-imine synthesis of β-lactam using chloroacetyl chloride. The designed chemicals’ synthesis has been completed successfully. Physical parameters (melting points and Rf values), Fourier transfo

This work involved the successful synthesis of three new Schiff base complexes, including Ni(II), Mn(II), and Cu(II) complexes. The Schiff base ligand was created by reacting the malonyldihydrazide molecule with naphthaldehyde, and the final step involved reacting the ligand with the corresponding metallic chloride yielding pure target complexes. FTIR, 1 H NMR, 13 C NMR, mass, and UV/Vis spectroscopies were used to comprehensively characterize the produced complexes. These substances have been employed in this study to photo-stabilize polystyrene (PS) and lessen the photo-degradation of its polymeric chains. Several methods, including FTIR, weight loss, viscosity average molecular weight, light and atomic force microscopy, and energy disper