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), adhesive
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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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At atmospheric pressure and at a frequency of 9.1 kHz, a constructed magnetically stabilized tornado gliding arc discharge (MSGAD) system was utilized in this study to generate a non-thermal plasma with an alternating voltage source from 2,4,6,8 to 10 kV. Argon gas was used to generate the arc plasma with an adjustable flow rate using a flow meter regulator to stabilize the gas flow rate to 2 L/min. A gliding plasma discharge is achieved by a magnetic field for the purpose of a planned investigation. The influence of the magnetically stabilized tornado gliding arc discharge parameters such as magnetic field and applied voltage on microscopic tornado plasma parameters was studied. The electron temperature1was measured using a Boltzmann plot
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In this paper, a construction microwave induced plasma jet(MIPJ) system was used to produce a non-thermal plasma jet at atmospheric pressure, at standard frequency of 2.45 GHz and microwave power of 800 W. The working gas Argon (Ar) was supplied to flow through the torch with adjustable flow rate using flow meter regulator. The influence of the MIPJ parameters such as applied voltage and argon gas flow rate on macroscopic microwave plasma parameters were studied. The macroscopic parameters results show increasing of microwave plasma jet length with increasing of applied voltage, argon gas flow rate where the plasma jet length exceed 12 cm as maximum value. While the increasing of argon gas flow rate will cause increasing into the ar
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Spatial data observed on a group of areal units is common in scientific applications. The usual hierarchical approach for modeling this kind of dataset is to introduce a spatial random effect with an autoregressive prior. However, the usual Markov chain Monte Carlo scheme for this hierarchical framework requires the spatial effects to be sampled from their full conditional posteriors one-by-one resulting in poor mixing. More importantly, it makes the model computationally inefficient for datasets with large number of units. In this article, we propose a Bayesian approach that uses the spectral structure of the adjacency to construct a low-rank expansion for modeling spatial dependence. We propose a pair of computationally efficient estimati
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The lowest layer of the atmosphere is called the atmospheric mixed layer, characterized by small-scale, irregular air motions defined by winds that change in speed and direction. Aerosol radiative effects impact the atmospheric boundary layer (ABL), which holds most aerosols in the lower atmosphere. Aerosol absorption and scattering both lower the quantity of solar energy that reaches the ground, which has an impact on the spectral signature of the land coverings. In this study, 51 locations in downtown Baghdad were chosen for four different types of land cover (water bodies, farms, open areas, and residential areas) for Sentinel 2 satellite imagery, and the time the pictures were taken was 8:00 am ( 22 March, 22 June, 20 September,
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Healthcare professionals routinely use audio signals, generated by the human body, to help diagnose disease or assess its progression. With new technologies, it is now possible to collect human-generated sounds, such as coughing. Audio-based machine learning technologies can be adopted for automatic analysis of collected data. Valuable and rich information can be obtained from the cough signal and extracting effective characteristics from a finite duration time interval that changes as a function of time. This article presents a proposed approach to the detection and diagnosis of COVID-19 through the processing of cough collected from patients suffering from the most common symptoms of this pandemic. The proposed method is based on adopt
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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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The research deals with the concept of a New Urbanism as an urban development strategy in the suburbs of cities or in its centers that are affected by pedestrian-oriented design and the possibility of walking, as well as integrating economic classes through the diversity of housing and its costs, and this works to facilitate access to jobs and services while providing more diverse neighborhoods and reducing the use of cars , As designing separate houses in the suburbs and increasing car trips poses a threat to the environment and the quality of urban life, and thus the new urban provides a good strategy for developing
... Show MoreA 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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