In this research, the seasonal Optimal Reliable Frequency (ORF) variations between different transmitter/receiver stations have been determined. Mosul, Baghdad, and Basra have been chosen as tested transmitting stations that located in the northern, center, and southern of Iraqi zone. In this research, the minimum and maximum years (2009 and 2014) of solar cycle 24 have been chosen to examine the effect of solar activity on the determined seasonal ORF parameter. Mathematical model has been proposed which leads to generate the Optimal Reliable Frequency that can maintain the seasonal connection links for different path lengths and bearings. The suggested ORF parameter represented by a different orders polynomial equation. The polynom

This article includes designed and synthesized for bent-shaped liquid crystal molecules starting from 5,5-diethylpyrimidine-2,4,6(1H,3H,5H)-trione and two moles of chloroacetylchloride in N, N-dimethyl formamide (DMF) and triethylamine (TEA) to product compound [I] ,then reacted the later compound with two moles of 4-hydroxybenzonitrile to yield nitrile compound [II]. Likewise, reaction 5,5-diethylpyrimidine-2,4,6(1H,3H,5H)-trione and two moles of ethylchloroacetate with fused sodium acetate in ethanol to create an ester compound [III], and then the later compound was reacted with two moles of hydrazine hydrate in ethanol to obtained hydrazide acid compound [IV]. After that, the compound [IV] reacted with two moles of ethyl acetoacetate in

A set newly complexes with the general formula [M(L)Cl2] are resulting from the reaction of a new schiff base ligand [Ethyl (6R,7R)-7-((E)-2-((2-ethoxy-2- oxoethoxy)imino)-2-(2-(((E)-4-nitrobenzylidene) amino) thiazol -4- yl) acetamido) -8- oxo -3- vinyl -5- thia -1-aza bicyclo [4. 2.0] oct -2- ene -2- carboxylate] (L). This ligand was derived from the reaction of the two substances 4-nitrobenzaldehyde and precursor (P). Reaction the ligand with metal ions M= Mn(II), Co(II), Ni(II), Cu(II) and Cd(II) afforded new complexes which are characterized by FT-IR and Electronic Spectra. These measurements indicate that the complexes have a tetrahedral geometry. The Penicillin-Binding Protein 3 (PBP3) of Staphylococcus aureus and the target protein

The purpose of the study is to synthesize and characterize a new polytriazole derivative from polyacryloyl chloried, first reaction of polyacryloyl chloride with hydrazine hydrate in the presence of DMF as a solvent to obtained acid hydrazide (1) than reacted with different amide to give poly 1,2,4-triazole derivatives(1a-1c). Newly synthesized compounds were characterized by spectral methods [13C-NMR, 1H-NMR, and FTIR] and calculated some of its physical properties. Also, we worked theoretical study involving calculated the geometric configurations, total energy, dipole moment etc..,. In addition, the inhibition effect of the synthesized compounds (1a-1c) on corrosion of stainless steel in 1M HCl were studied by method of weight lo

The compound azobenzen-p,p'-di(2-amine-1,3,4-thiadiazol-5-yl) (A) was formed by reacting 4,4'-(diazene-1,2-diyl)-dibenzoyl chloride with thiosemicarbazide. Ten substituted amino derivatives of azobenzen-p,p'-di(2- amine-1,3,4-thiadiazol-5-yl) were synthesized by reaction of compound (A) with formaldehyde and acetaldehyde to give Schiff base. The compound (A) reaction with sodiumcyanat and potassiumisothiocyanat gave uredo and thiouredo-1,3,4-thiadizol-5-yl. However, its reaction with benzenesulphonyl chloride and 4-methyl benzene sulphonyl chloride gave sulphonamido compounds, while its reaction with acetylchloride and benzoyl chloride gave acetamido and benzamido derivatives. Its reaction with succinic and glutaric acid gave succinamido an

The interest of many companies has become dealing with the tools and methods that reduce the costs as one of the most important factors of successful companies, and became the subject of the attention of many economic units because of the impact on the profits of company, and since the nineties of the last century the researchers and writers gave great attention to this subject, especially in light of the large competition and rapid developments in cost management techniques, as well as the wide and significant change in production methods that have been directed towards achieving customer satisfaction, all this and more driven by economic units in all sectors whether it is service or productivity to find methods that would reduc

Abstract

The research aims to investigate the private sector attitudes toward operational contracting in special education schools. The research adopted the qualitative approach by using personal interviews with a sample of (45) private school owners and managers in Oman. The results of the research revealed that there is an agreement among the majority of respondents on the ability of the private sector to manage special education schools, the advantages of the partnership, as well as the need for guarantees to support this partnership. The government should fully assume it. The role of the private sector remains to raise the operational efficiency of schools. Opinions vary about the level of powers granted to t