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: One of the drawbacks of vital teeth bleaching is color stability. The aim of the present study was to evaluate the effects of tea and tomato sauce on the color stability of bleached enamel in association with the application of MI Paste Plus (CPP-ACPF). Materials and Methods: Sixty enamel samples were bleached with 10% carbamide peroxide for two weeks then divided into three groups (A, B and C) of 20 samples each. After bleaching, the samples of each group were subdivided into two subgroups (n=10). While subgroups A1, B1 and C1 were kept in distilled water, A2, B2, and C2 were treated with MI Paste Plus. Then, the samples were immersed in different solutions as follow: A1 and A2 in distilled water (control); B1 and B2 in black
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Background: The aim of this study was to evaluate the shear bond strength (SBS) and adhesive remnant index (ARI) of different orthodontic adhesive systems after exposure to aging media (water storage and acid challenge). Materials and methods: Eighty human upper premolar teeth were extracted for orthodontic purposes and randomly divided into two groups (40 teeth each): the first group in which the bonded teeth were stored in distilled water for 30 days at 37°C, and the second group in which the bonded teeth were subjected to acid challenge. Each group was further subdivided into four subgroups (10 teeth each) according to the type of adhesive system that would be bonded to metal brackets: either non-fluoride releasing adhesive (NFRA),
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ABSTRACT Background: Color changes that are detectable to human eye can affect the esthetic appearance of ceramic veneers. The purpose of this study was to evaluate and compare the effect of artificial accelerated aging on the color of ceramic veneers cemented with different resin cements. Materials and Methods: Sixty discs were prepared with 0.5 mm thickness, 30 discs made from IPS e.max press (Ivoclar Vivadent) and 30 discs were made from VITA Enamic (VITA Zahnfabrik). The discs were cemented with three resin cements: Variolink Veneer MV 0 shade (Ivoclar Vivadent), Rely X veneer Translucent shade (3M ESPE) and NX3 Nexus Clear shade (Kerr Corporation) with 0.1 mm thickness. The spectrophotometer Easyshade Advance was used to measure the co
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Density functional theory (DFT) with B3LYP level and 6-311G[Formula: see text] basis sets for light atoms like N and O and SDD basis sets for heavy atoms like Sn is used to examine the interaction of tin dioxide nanocrystals with nitrogen dioxide as a function of temperature from 273[Formula: see text]K to 373[Formula: see text]K through a Gaussian 09W software program. Gibbs free energy, enthalpy, and entropy of activation and reaction are calculated. The situation of transition of SnO2 clusters toward nitrogen dioxide is investigated. According to the findings, the activation energy of SnO2 clusters with nitrogen dioxide increases as the temperature rises (in negative value). Gauss view 0
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Focused research aims to provide a framework cognitive analytical nature of real estate investments and how they evaluated in the light of the assessment tools of modern theory of real options, and the possibility to rely on that theory in the detection of the true value of projects, real estate investments that would maximize the value of the investment decision taken, and the analysis of those projects that arise in the real estate markets and environments is the organization, which she was to make sure cases and high-risk, compared with entrances techniques, discounted cash flow (net present value). Based on the assumption lies in the possibility of the application of the implic
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The main aim of this study is to investigate the ability of four local entomopathogenic isolates Beauveria bassiana (Bals.) and Metarhizium anisopliae (Met.) to control the mosquito larvae in the lab. The results revealed that the isolate (MARD48) B .bassiana reduced the survival rate of the mosquito larvae to (80%) followed by the isolate M. anisopliae (MARD10) to (90%) in the first two days of treatment, and 60 and 66% respectively in the third day. The results also showed that the isolate B. bassiana (MARD48) killed 50% of the population (LC50) with the concentration 1×104 conidia/ml compared to 1×107 conidia/ml for the isolates B. bassiana (MARD14) and M. anisopliae (MARD10), and 1×108 conidia/ml for the isolate B .bassiana (MARD76).
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The search aims to clarify pollution to negative effects on environment and to an increasing in the dangerous polluted materials that discharged out these factories. To make active procedures in order to limit the environmental pollution.
The search problem came from an assumption which has the researched factory is suffering from the lack of applying the international specification ( ISO 14004 ). The research problem assimilated by these questions:
- What is the level or organization in thinking of environmental system according to ISO 14004 .
- What are the requirements used in researched factor
Isolation of fungi was performed from February to July, 2019. One hundred clinical specimens were collected from King Abdullah Hospital (KAH) Bisha, Saudi Arabia. Samples were collected from twenty patients of different ages (30 - 70 years old) ten males and ten females. The samples were collected from patients with the two types of diabetics. Specimens included blood, hair, nail, oral swabs and skin. Specimens were inoculated on Sabourauds Dextrose agar containing chloramphenicol. Thirteen fungal species were isolated and identified. The isolated species were: Aspergillus flavus, A. niger, A. terrus, A. nidulans, A. fumigatus, Candida albicans, C. krusei, C. parapsilosis, C. Tropicalis, Curvularia lunata, Fusarium solani, Penicill
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The effect of different doses of gamma rays that emitted from 60Co on the development of different stages of lesser grain borer Rhyzopertha dominica (Fab.) was investigated . The results showed that the eggs in both early (1-3 days) and late (7-9) old were very sensitive to gamma rays and its hatch was zero at 10 Gy for both ages in comparison with 83.3% for the control group. Furthermore, the results illustrated that the larval stage in its two old ages were different in the radiosensitivity, the percent of its death were 100% & 96.6% when they exposed to 100 & 120 Gy, respectively. Moreover, the results showed that the sensitivity of pupal stage at age of 1-3 days was increased with increasing the doses of gamma rays, the percent of no
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