New thermally stable aromatic poly(amide-imide)s ( PAI1- PAI4 ) were synthesized from direct polycondensation reaction of Terephthalic acid and Phthalic acid with two new different diamine monomers derivatives of 1,2,4,5-tetracarboxilic benzene dianhydride as a second diacides in a medium consisting of triphenyl phosphite (TPP) in N-methyl-2pyrrolidone (NMP) / pyridine solution containing dissolved calcium chloride CaCl2. The polymerization reaction produced a series of novel poly(amide-imide) in high yield. The new monomers were characterized by FTIR, 1H-NMR spectroscopy. The resulting polymers were typically characterized by means of FT-IR, 1H-NMR spectroscopy, and solubility tests. Thermal properties of the poly(amide-imide)s were also investigated using differential scanning calorimetry (DSC). Data obtained by thermal analysis revealed that these polymers showed very good thermal stability. These polymers were readily soluble in various organic solvents.
Abstract
A series of new 4(3H)-quinazolinone derivatives (S1-S4) were synthesized and characterized by FTIR,1HNMR and 13CNMR .Their cytotoxic activity against a set of human cancer cell lines MCF-7 (breast) and A549 (lung) was evaluated using MTT assay. To detect their selectivity toward cancer cells, the compounds were also tested against epithelial cells derived from normal human fibroblast (NHF). Methotrexate (MTX) was used as a reference for comparison . All the tested compounds exhibited toxicity against the normal cells lower than cancer cells. All the tested compounds displayed higher cytotoxicity against lung cancer cell line (A549) than MTX with the most
... Show MoreThis paper deals with the mathematical method for extracting the Exponential Rayleighh distribution based on mixed between the cumulative distribution function of Exponential distribution and the cumulative distribution function of Rayleigh distribution using an application (maximum), as well as derived different statistical properties for distribution, and present a structure of a new distribution based on a modified weighted version of Azzalini’s (1985) named Modified Weighted Exponential Rayleigh distribution such that this new distribution is generalization of the distribution and provide some special models of the distribution, as well as derived different statistical properties for distribution
New, simple and sensitive batch and Flow-injecton spectrophotometric methods for the determination of Thymol in pure form and in mouth wash preparations have been proposed in this study. These methods were based on a diazotization and coupling reaction between Thymol and diazotized procaine HCl in alkaline medium to form an intense orange-red water-soluble dye that is stable and has a maximum absorption at 474 nm. A graphs of absorbance versus concentration show that Beer’s law is obeyed over the concentration range of 0.4-4.8 and 4-80 µg.ml-1 of Thymol, with detection limits of 0.072 and 1.807 µg.ml-1 of Thymol for batch and FIA methods respectively. The FIA procedure sample throughput was 80 h-1. All different chemical and physical e
... Show MoreAn abstract is a brief summary of a research article, thesis, Schiff base ligand (L) was prepared by the reaction of 4-aminantipyrine with o-phenylenediamine, the prepared ligand characterized by Micro elemental Analysis, FT. IR, UV-Vis, and 1H,13C-NMR spectroscopy.complexes of Mn(II), Co(II), Ni(II), Cu(II) and Hg(II) with Schiff base and 1,10-phenanthroline (Phen) have been investigated in aqueous ethanol with (1:1:1) (M:L:Phen). The prepared complexes were characterized using flame atomic absorption, (C. H. N) Analysis, FT. IR and UV-Vis spectroscopic methods as well as magnetic susceptibility and conductivity measurements. From the obtained data the octahedral structure was suggested for all complexes. The biological screening effects o
... Show MorePolyaniline nanofibers (PAni-NFs) have been synthesized under various concentrations (0.12, 0.16, and 0.2 g/l) of aniline and different times (2h and 3 h) by hydrothermal method at 90°C. Was conducted with the use of X-ray diffraction (XRD), Fourier Transform Infrared spectra (FTIR), Ultraviolet-Visible (UV-VIS) absorption spectra, Thermogravimetric Analysis (TGA), and Field Emission-Scanning Electron Microscopy (FE-SEM). The X-ray diffraction patterns revealed the amorphous nature of all the produced samples. FE-SEM demonstrated that Polyaniline has a nanofiber-like structure. The observed typical peaks of PAni were (1580, 1300-1240, and 821 cm-1 ), analyzed by the chemical bonding of the formed PAni through FTIR spectroscopy. Also, tests
... Show MoreBackground: Behçet’s disease (BD) is a disorder of systemic inflammatory condition. Its important features are represented by recurrent oral, genital ulcerations and eye lesions. Aims. The purpose of the current study was to evaluate and compare cytological changes using morphometric analysis of the exfoliated buccal mucosal cells in Behçet’s disease patients and healthy controls, and to evaluate the clinical characteristics of Behçet’s disease. Methods. Twenty five Behçet’s disease patients have been compared to 25 healthy volunteers as a control group. Papanicolaou stain was used for staining the smears taken from buccal epithelial cells to be analyzed cytomorphometrically. The image analysis sof
... Show MoreIn this paper, the Monte-Carlo simulation method was used to compare the robust circular S estimator with the circular Least squares method in the case of no outlier data and in the case of the presence of an outlier in the data through two trends, the first is contaminant with high inflection points that represents contaminant in the circular independent variable, and the second the contaminant in the vertical variable that represents the circular dependent variable using three comparison criteria, the median standard error (Median SE), the median of the mean squares of error (Median MSE), and the median of the mean cosines of the circular residuals (Median A(k)). It was concluded that the method of least squares is better than the
... Show Moreoptical properties of pure poly(vinyl Alcohol) films and poly(vinyl Alcohol) doped with methyl red were study, different percentage prepared with constant thickness using casting technique. Absorption, Transmission spectra have been recorded in order to study the optical parameters such as absorption coefficient, energy gap, refractive index, Extinction coefficient and dispersion parameters were measured in the wavelength range (200-800)nm. This study reveals that the optical properties of PVA affect by increasing the impurity concentration.
A sensitive film was manufactured Holokravaa using plastic materials the a Akougl substantive Amaid with poly alcohol Funnell addition to sensitive material Daakromat ammonium were obtained registry Qakma to diffraction efficiency of 83%
The present study introduces description of a new species of leafhopper of genus Assuita Lindberg; 1969. This study includes external morphological characters and the spotting patterns and photos of vertex face pronotum, mesonotum, fore wing, hind wing and the shape of male abdominal abodeme, also aedeagus, connective, genital style and genital plate.