The purpose of my thesis is to prepare four new ligands (L1-L4) that have been used to prepare a series of metal complexes by reacting them with metal ions: M=(Mn(II), Co(II), Ni(II), Cu(II), Zn(II), Cd(II), Hg(II) Where succinyl chloride was used as a raw material for the preparation of bi-dented ligands (L1-L4) by reacting it with potassium thiocyanate as a first step and then reacting with (2-aminobenzothiazole, Benzylamine, 4-aminoantipyrine, Sulfamethoxazole) respectively as a second step with the use of dry acetone as a solvent, the chemical formula of the four ligands prepared in succession: N1,N4-bis(benzo[d]thiazol-2-ylcarbamothioyl)succinamide (L1) N1,N4-bis(benzylcarbamothioyl)succinamide (L2) N1,N4-bis((1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4-yl) carbamothioyl)succinamide (L3) N1,N4-bis((4-(N-(5-methylisoxazol-3-yl)sulfamoyl) phenyl) carbamo thioyl) succinamide (L4) The new ligands were identified using spectroscopic measurements that included (FT-IR spectra, UV-Vis spectra, and nuclear magnetic resonance (1H, 13CNMR) spectra, mass spectra, elemental analysis (C.H.N.S), and thermal analysis (TGA&DSC), as the results of the measurements proved to be identical to the proposed molecular formula for these ligands. A series of metal complexes for ligands was also prepared, which included seven complexes for each ligand, by adding each of the metal ions to the four ligands prepared in succession to produce the following molecular formulas: - [M2(L)Cl4] , L= L1, L2, L3, L4 (M= Mn(II), Co(II), Ni(II), Cu(II), Zn(II), Cd(II), Hg(II)) The prepared complexes were diagnosed by several techniques, including the study of the infrared spectra of the prepared complexes, and when comparing those spectra with the spectra of each of the four ligands prepared in the free form, these gave clear changes, including the emergence of a new band within the fingerprint area. It was not originally present in the spectra of ligands in their free form, and this is due to the occurrence of coordination between the metal ions under study and the donor atoms, which are the oxygen atom of the (C=O) group, and the sulfur atom of the (C=S) group in the ligands. (L1-L4), while other distinct bands were obtained with clear changes in shape, intensity, and location, and this is an indication of the occurrence of a coordination process between the metal ions under study and the four prepared ligands. The percentage of metal ions in the prepared complexes was determined by flame atomic absorption spectrometry, where it was shown from the careful analysis of the elements the great agreement between the percentages calculated theoretically and obtained practically. The magnetic sensitivity results showed that some of the prepared metallic complexes have paramagnetic properties. The measurements of the molar conductivity of the prepared complexes dissolved in DMSO at a concentration of 1×10-3 M and at the laboratory temperature showed that they are of a non-electrolytic nature. The prepared complexes were also studied through solubility, melting point, and ultraviolet-visible techniques, and through the data of all the aforementioned techniques, structural formulas were proposed for the prepared complexes, through which it was found that the prepared ligands are bivalve chelating ligands that lead to their participation as ligand into complexes with a tetrahedral geometric shape for all metallic complexes under study. The research included a study evaluating the antioxidant activity of some selected metal complexes by studying the amount of radical scavenging of DPPH* compared to ascorbic acid as an antioxidant reference agent. The zinc complex showed higher activity than the nickel complex compared to standard ascorbic acid. The [Cu2(L1)Cl4] and [Co2(L1)Cl4] complexes were also tested as antibodies to inhibit the breast cancer cell line (MCF-7) and compared with the normal cell line (HdFn), where the copper complex showed the ability to inhibit the cancerous cell line compared with the cobalt complex. The molecular binding of ligands (L3) and (L4) was also studied, and their possibility of using them as drugs in the treatment of some diseases, where the ligand L3 showed better association with the active site of the enzyme than the ligand L4, and is expected to highest antimicrobial effect. Finally, the biological effect of the prepared ligands and some of their complexes on the growth of two types of bacteria, Escherichia coli and Staphylococcus aureus, was studied using DMSO solvent, where the complexes showed greater activity than the ligands against the selected types of bacteria.
Background: Women with previous two or
more caesarean deliveries are usually
managed by elective cesarean section to avoid
the possible risks of labor.
Objective: To compare the relative risks of
maternal and fetal outcomes in emergency
versus elective previous two or more
caesarean deliveries
Design: Randomized prospective clinical
study
Setting: Al-Elweya Maternity Teaching
Hospital, from 1st of March to 31st of
September 2008.
Methods: The study groups, those who had
previous two or more caesarean deliveries,
were included from the hospital admissions.
The 1st group (102 women) presented in labor
and was managed by caesarean delivery as
soon as it was possible. The second group (7
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Rutting has a significant impact on the pavements' performance. Rutting depth is often used as a parameter to assess the quality of pavements. The Asphalt Institute (AI) design method prescribes a maximum allowable rutting depth of 13mm, whereas the AASHTO design method stipulates a critical serviceability index of 2.5 which is equivalent to an average rutting depth of 15mm. In this research, static and repeated compression tests were performed to evaluate the permanent strain based on (1) the relationship between mix properties (asphalt content and type), and (2) testing temperature. The results indicated that the accumulated plastic strain was higher during the repeated load test than that during the static load tests. Notably, temperatur
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This paper proposes a new encryption method. It combines two cipher algorithms, i.e., DES and AES, to generate hybrid keys. This combination strengthens the proposed W-method by generating high randomized keys. Two points can represent the reliability of any encryption technique. Firstly, is the key generation; therefore, our approach merges 64 bits of DES with 64 bits of AES to produce 128 bits as a root key for all remaining keys that are 15. This complexity increases the level of the ciphering process. Moreover, it shifts the operation one bit only to the right. Secondly is the nature of the encryption process. It includes two keys and mixes one round of DES with one round of AES to reduce the performance time. The W-method deals with
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The study aims at knowing the relationship between retirement problems and psychological flexibility, besides identifying the difference of retirement problems and psychological flexibility due to the wok place variable and sex variable.
The study sample consists of 250 registered retirees in both associations of the government and the UNRWA. The researcher had prepared and used a retirement problems scale and a psychological flexibility scale. The study findings show the following:
- The economic problems were greatly common by a relative weight of 76.3 %.
- The psychological compatibility was the most widespread domain in the psychological fl
The present work is an attempt to develop design data for an Iraqi roof and wall constructions using the latest ASHRAE Radiant Time Series (RTS) cooling load calculation method. The work involves calculation of cooling load theoretically by introducing the design data for Iraq, and verifies the results experimentally by field measurements. Technical specifications of Iraqi construction materials are used to derive the conduction time factors that needed in RTS method calculations. Special software published by Oklahoma state university is used to extract the conduction factors according to the technical specifications of Iraqi construction materials. Good agreement between the average theoretical and measured cooli
... Show MoreConcerns about the environment, the cost of energy, and safety mean that low-energy cold-mix asphalt materials are very interesting as a potential replacement for present-day hot mix asphalt. The main disadvantage of cold bituminous emulsion mixtures is their poor early life strength, meaning they require a long time to achieve mature strength. This research work aims to study the protentional utilization of waste and by-product materials as a filler in cold emulsion mixtures with mechanical properties comparable to those of traditional hot mix asphalt. Accordingly, cold mix asphalt was prepared to utilize paper sludge ash (PSA) and cement kiln dust (CKD) as a substitution for conventional mineral filler with percentages ranging fro
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Finding communities of connected individuals in complex networks is challenging, yet crucial for understanding different real-world societies and their interactions. Recently attention has turned to discover the dynamics of such communities. However, detecting accurate community structures that evolve over time adds additional challenges. Almost all the state-of-the-art algorithms are designed based on seemingly the same principle while treating the problem as a coupled optimization model to simultaneously identify community structures and their evolution over time. Unlike all these studies, the current work aims to individually consider this three measures, i.e. intra-community score, inter-community score, and evolution of community over
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