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.
The research aims to determine the role of training strategy dimensions of (trainers، curriculum training programs، trainees and their desire for training، administrative and supervisory services and their impact on the success of the training program) in the entrepreneurial performance of the organization dimensions of (pre-planning، renovation and modernization، efficiency، effectiveness)، so search ranks of great importance because it addresses an important and modern issue in performance entrepreneurial، and strategy training، aware of the importance of the subject and expected outcomes (General company for electrical Industries - motor plant) surveyed، was an analysis of data obtained through field visits in addition to the q
... Show More The reaction of L-ascorbic acid with the tirchloroacetic acid in the presence of potassium hydroxide gave new product Bis[O,O-2,3;O,O-5,6(chlorocarboxylicmethyliden)]Lascorbic acid (H2L) which was isolated and characterized by 1H,13C-NMR, elemental analysis (C,H,N), UV-Visible and Fourier Transform Infrared (FTIR). The complexes of the ligand (H2L) with metal ions, M+2= (Cu, Co, Ni, Cd and Hg) were synthesized and characterized by FTIR, UV-Visible, molar conductance, atomic absorption, magnetic susceptibility and the molar ratio. The analysis evidence showed the binding of the metal ions with (H2L) through the bicarboxylato group manner resulting in six-coordinated metal ion. The TLC for (H2L) and complexes showed one spot for eac
... Show MoreThe modern industrial projects and complexes that adopt ecological systems, and renewable, clean and environmentally friendly energy, not only contribute to the development of an environmentally friendly production method but can achieve long-term economic and industrial development by preserving environmental resources. The ecological industrial systems and modern industrial technologies are the ideal solutions to rationalize excessive use and preserve the elements of the environment and natural resources, the most important of which is the existence of several methods and programs for the development of industrial sites, and there is important to adopt mechanisms and programs to sol
The largest use of x-ray in medical by dentists, employers or persons that needed by patients with specific conditions, lead to higher exposure of x-ray that may cause many diseases. In the present work radiography films have been used in evaluating the efficiency of using unsaturated polyester polymer reinforced with lead oxide (PbO) as shield material for medical x-ray devices, many parameters studied like concentration and thickness that they are increasing the attenuation of x-ray in them. The results show that the attenuation of X-ray increasing with concentration of reinforced material and with thickness, and the optical density decreases with increasing concentration from 0% to 50%, we chose 30% as suitable concentration to increase
... Show Morehis study aims to determine most stable isobar from some isobaric elements with mass number (A= 50-65 & 180-195). This aim achieved by, firstly: plot mass parabolas for these isobaric family, second: calculated the atomic number for most stable isobar (ZA) value. To plot the mass parabola, the binding energy (B.E) calculated from semi empirical formula for these isobars. The mass number (A) plotted as a function to the (ZA) for each range; we get a linear relationship between them. An empirical formula for the most stable isobar has been developed from this linear dependence. From the results, we can see that mass parabolas for isobaric elements with odd mass number (A) are different from the mass parabolas of even mass number (A) isobars,
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