This research discloses the synthesis of various polyester resins, the polyesters containing homoring aromatic and others heterocyclic were synthesized by the condensation polymerization of suitable monomers (which are containing variety function groups in different structures) with phthalic anhydride. The main objective is synthesis of new polyester with keeping a reasonable electrical insulating behavior. The structural of polymer was characterized by Fourier Transform infra-red spectroscopy FTIR and HNMR. The dielectric constant (real ε' and imaginary parts ε") and AC conductivity (σAC) for all the polyester samples are studied by varying the frequency (30, 50, 70, 90, 120, 300, 500Hz and 1KHZ) at 25⁰ C. Indeed, study of the electrical behavior of various polyesters revealed that the cross-linked polyesters presents higher insulating behavior at room temperature than linear polymers. Thermo gravimetric analysis (TGA) and differential scanning calorimetry (DSC) were employed to study the thermal stability for these polymers.
الخلاصة لقد شكل المحافظون الجدد وهم بالأساس نخبة من المثقفين ومن السياسيين الأمريكيين كتلة ضغط كبيرة التأثير على الإدارة في عهد الجمهوريين. حمل هؤلاء المحافظون مشروعاً إيديولوجياً البسوه لسلطة الجمهوريين وهو يهدف إلى جعل أمريكا سيدة العالم من دون منازع خاصة بعد انهيار الاتحاد السوفييتي ونهاية الحرب الباردة. واكب هذا الحدث التاريخي الكثير من الأفكار ومنها (نهاية التاريخ)، وصراع الحضارات، وكذ
... Show MoreOil from Brassca campestris (local variety) was extracted with hexane using Soxhlet. The extracted oil was characterized and its antimicrobial activity was determined as well. The content of extracted oil was 40% with 0.5% of volatile oil .Oil was immiscible with polar solvent such as ethanol, acetone and water, while it was easily miscible with chloroform due to its hydrophobicity. The result of organoleptic tests revealed that the oil is clear yellow in color and odorless with acceptable taste. The oil was stable at 4 -25 C? for a month. Refractive index (RI) of oil was 1.4723 with density of 0.914, [both at 4-25 C?]. Boiling point 386 C?. Infra red spectroscopy (IR) indicated the presence of different chemical groups (C=C
... Show More.Curcumin (Cur) and L phenylalanine (Phy) compounds were used to prepare two mixed ligand complexes with Cr (III) and Fe (III) ions. The synthesized complexes are characterized by using conductivity measurement and different spectral methods like FT-IR and UV- Vis .Molar conductance and analytical studies confirmed that the complexes exhibit octahedral geometry., suggest that the complexes are formed in 1: 1 :2 [ L : Metal : 2phe ] ratio and they proposed to have the general formulae [M(Cur)(phe)2] Cl (M= Cr (III) and Fe (III) The compound dyeing method was studied and applied to acrylic fabric.The antibacterial activity of curcumin, phenylalanine and their mixed ligand complexes were examined on pathogenic bacterial strains and showed good
... Show MoreThe fabrication of Solid and Hollow silver nanoparticles (Ag NPs) has been achieved and their characterization was performed using transmission electron microscopy (TEM), zeta potential, UV–VIS spectroscopy, and X-ray diffraction (XRD). A TEM image revealed a quasispherical form for both Solid and Hollow Ag NPs. The measurement of surface charge revealed that although Hollow Ag NPs have a zeta potential of -43 mV, Solid Ag NPs have a zeta potential of -33 mV. According to UV-VIS spectroscopy measurement Solid and Hollow Ag NPs both showed absorption peaks at wavelengths of 436 nm and 412 nm, respectively. XRD pattern demonstrates that the samples' crystal structure is cubic, similar to that of the bulk materials, with
... Show MoreSome physical and chemical characteristics of Jurf Al- Sakar drinking water plant in Babylon governorate have been studied. Seven locations for this plant were selected. These were the drinking water treatment plant source on Euphrates River before entering the plant, precipitation, filtration and collection tanks, and also after leaving the plant at distances of one meter, 4 and 8 km. The samples were collected bimonthly from October, 2002 to August, 2003. Some results match with the national and international standard characters while the other characters (Turbidity, total hardness, calcium, nitrate, phosphate and the biological oxygen demand values) were not match. The present study showed that drinking water treatment plant is undrinka
... Show MoreA study were conducted to examinate the effect of organic and aqueous (Hot, Cold) Extracts from leaves of Duranta repens on the growth and activities of the following types of Bacteria:- Staphylococcus aureus,Streptococcus pyogens ,Escherichia coli,Klebsilla pneumonia, in addition to the yeast Candida albicans and the fungi Aspergullis niger ,Aspergulls flavus.The result showed that gram Positive Bacteria is more sensitive to the extracts than gram negative bacteria with Minimum inhibitory concentration (MIC) value (50,25,50,100)% and Minimum Bactericidal Concentration (MBC) value (100,50,200,100)% for all types Bacteria respectively . The most active extract against A.niger ,A,flavus was cold and hot aqueous extract from the leaves with d
... Show MoreThis study aimed at some of the criteria used to determine the form of the river basins, and exposed the need to modify some of its limitations. In which, the generalization of the elongation and roundness ratio coefficient criterion was modified, which was set in a range between (0-1). This range goes beyond determining the form of the basin, which gives it an elongated or rounded feature, and the ratio has been modified by making it more detailed and accurate in giving the basin a specific form, not only a general characteristic. So, we reached a standard for each of the basins' forms regarding the results of the elongation and circularity ratios. Thus, circular is (1-0.8), and square is (between 0.8-0.6), the blade or oval form is (0.6-0
... Show MoreGallium arsenide diamondoids structural and vibrational properties are investigated using density functional theory at the PBE/6-31(d) level and basis including polarization functions. Variation of energy gap as these diamondoids increase in size is seen to follow confinement theory for diamondoids having nearly equiaxed dimensions. Density of energy states transforms from nearly single levels to band structure as we reach larger diamondoids. Bonds of surface hydrogen with As atoms are relatively localized and shorter than that bonded to Ga atoms. Ga-As bonds have a distribution range of values due to surface reconstruction and effect of bonding to hydrogen atoms. Experimental bulk Ga-As bond length (2.45 Å) is within this distribu
... Show MoreBackground: Many materials were proposed as root canal obturating materials but the biocompatibility issue remains to be a critical one. Propolis has been used as a therapeutic agent since the time of Hippocrates. It is known that propolis exhibits some pharmacological activities, such as antibacterial, antiviral, antifungal and anti inflammatory activity. Materials and methods: Eighteen albino rats were used in the study and divided randomly into three groups of 6 animals for each group. Each group was scheduled to be sacrificed at different time periods, which were three days, one week and three weeks. Propolis and ZOE sealer implants of 4mm in diameter and 0.5 gm in weight were implanted in the dorsal side of the rats. At the end of the
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