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: This in vitro study compares a self-etch primer (SEP) to an etch-and-rinse (EaR) for bonding sapphire brackets by evaluation of the enamel etch-pattern, shear bond strength, amount of remnant adhesive and enamel surface damage following thermal and fatigue cyclic loading. Material and Methods: Ceramic (sapphire) brackets were bonded to 80 extracted human premolars using two enamel etching protocols: conventional EaR using 37% phosphoric acid (PA) gel (control), and a SEP (Transbond Plus). Each group was subdivided into two subgroups (n=20 teeth) according to the time of bracket debonding: after 24 h water storage or following 5000 thermo-cycles plus 5000 cycles fatigue loading, to determine the shear bond strength (SBS), adhesiv
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A numerical simulation is made on the thermal lensing effect in an laser diode end-pumped Nd:YAG laser rod. Based on finite element method (FEM), the laser rod temperature distribution is calculated and the focal length is deduced for a Gaussian and super-Gaussian pump beam profiles.
At the pump power of 20W, the highest temperature located at the center of end-pumped face was 345K, and the thermal lens focal length was 81.4mm along the x-z axis.
The results indicate that the thermal lensing effect sensitively depend on the pump power, waist radius of the pump beam and the pump distribution in a laser rod geometry.
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Triticale is a hybrid of wheat and rye grown for use as animal feed. In Florida, due to its soft coat, triticale is highly vulnerable to Sitophilus oryzae L. (rice weevil) and there is interest in development of methods to detect early-instar larvae so that infestations can be targeted before they become economically damaging. The objective of this study was to develop prediction models of the infestation degree for triticale seed infested with rice weevils of different growth stages. Spectral signatures were tested as a method to detect rice weevils in triticale seed. Groups of seeds at 11 different levels (degrees) of infestation, 0–62%, were obtained by combining different ratios of infested and uninfested seeds. A spectrophotometer wa
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1,3,4-oxadizole and pyrazole derivatives are very important scaffolds for medicinal chemistry. A literature survey revealed that they possess a wide spectrum of biological activities including anti-inflammatory and antitumor effects.
To describe the synthesis and evaluation of two classes of new niflumic acid (NF) derivatives, the 1,3,4-oxadizole derivatives (compounds 3 and (4A-E) and pyrazole derivatives (compounds 5 and 6), as EGFR tyrosine kinase inhibitors in silico and in vitro.
The designed compounds were synthesized using convent
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An experimental study was carried out for an evaporative cooling system in order to investigate the effect of using an aluminum pad coated with fabric polyester. In the present work, it was considered to use a new different type of cooling medium and test its performance during the change in the wet-bulb temperature and dry-bulb temperature of the supply air outside of the pad, the relative humidity of the supply air, the amount of air supplied (300-600) CFM and also the change of the amount of circulated water (1.75, 2.5, 4.5) liter per minute. A decrease in the WBT of the air was obtained, whereas the WBT of the air entering the pad was 26.5 . In contrast, the WBT of the outside air had reached 23 even though eva
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Background. Material tribology has widely expanded in scope and depth and is extended from the mechanical field to the biomedical field. The present study aimed to characterize the nanocoating of highly pure (99.9%) niobium (Nb), tantalum (Ta), and vanadium (V) deposited on 316L stainless steel (SS) substrates which considered the most widely used alloys in the manufacturing of SS orthodontic components. To date, the coating of SS orthodontic archwires with Nb, Ta, and V using a plasma sputtering method has never been reported. Nanodeposition was performed using a DC plasma sputtering system with three different sputtering times (1, 2, and 3 hours). Results. Structural and elemental analyses were conducted on the deposited coating
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This work concerns the thermal and sound insulation as well as the mechanical properties of polymer matrix composite reinforced with glass fibers. These fibers may have dangerous effect during handling, for example the glass fibers might cause some damage to the eyes, lungs and even skin. For this reason the present work, investigates the behavior of polymer composite reinforced with natural fibers (Plant fibers) as replacement to glass fibers. Unsaturated Polyester resin was used as matrix material reinforced with two types of fibers, one of them is artificial (Glass fibers) and the other type is natural (Jute, Fronds Palm and Reed Fibers) by hand lay-up technique. All fibers are untreated with any chemical solvent. The Percentage of mi
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A study of Zooplankton community has been carried out at four selected sites on Dukan Lake. Samples of water and zooplankton were collected monthly for the period from July 2015 to February 2016. Some physical and chemical properties of water were studied and the results showed that the air temperature were ranged from 0 to 36.16 °C, water temperature ranged from 2.83 to 34.66 °C, hydrogen ion concentration of studied sites were found to lie in alkaline side, it was ranged between 6.87 to 8.57, electrical conductivity ranged from 190.79 to 850.08 µs.cm¹, turbidity ranged from 0.9-7.7 NTU, and dissolved oxygen from 3.3 to 6.8 mg.l-¹ while BOD5 were ranged from 0.53 to 34.66 mg.l-¹. Concerning to the zooplankton, 37 species were ident
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