This contribution reports a comprehensive investigation into the structural, electronic and thermal properties of bulk and surface terbium dioxide (TbO2); a material that enjoys wide spectra of catalytic and optical applications. Our calculated lattice dimension of 5.36 Å agrees well with the corresponding experimental value at 5.22 Å. Density of states configuration of the bulk structure exhibits a semiconducting nature. Thermo-mechanical properties of bulk TbO2 were obtained based on the quasi-harmonic approximation formalism. Heat capacities, thermal expansions and bulk modulus of the bulk TbO2 were obtained under a wide range of temperatures and pressures. The dependency of these properties on operational pressure is very evident. Cleaving bulk terbium dioxide affords six distinct terminations. Bader's charge distribution analysis for the bulk and the surfaces portrays an ionic character for Tb-O bonds. In an analogy to the well-established finding pertinent to stoichiometric CeO2 surfaces, the (111):Tb surface appears to be the thermodynamically most stable configuration in the nearness of the lean-limit of the oxygen chemical potential. For the corresponding non-stoichiometric structures, we find that, the (111):O + 1VO surface is the most stable configuration across all values of accessible oxygen chemical potentials. The presence of an oxygen vacant site in this surface is expected to enable potent catalytic-assisted reactions, most notably production of hydrogen from water
Ethylenediamine was reacted in the first step with 2,5 – hexandion to produce the precursor [A] , then [A] was reacted with diethylmalonate to give the new tetradentate macrocyclic Ligand [H2L].This Ligand was reacted with some metal ions in ethanol to give a series of new metal complexes of the general formula [M(HnL)X]m ( where : M= CrIII , n = 0 , X= Cl2 , m= -1 ; M = MnII , FeII , NiII , CuII , n = 1 , X= Cl2 , m = -1 ; M = CoII , n = 0 , X = Cl , m = -1 ; M = PdII , n = 0 , X=0 , m = 0 ; M = CdII , n = 2 , X = 0 , m = +2 . All compounds were characterize
... Show MoreGhrelin and leptin are hunger hormones related to type 2 diabetes mellitus (T2DM), and the pathogenesis of T2DM is the abnormality in insulin secretion and insulin resistance (IR). The aim of this study is to evaluate ghrelin and leptin concentrations in blood and to specify the relationship of these hormones as dependent variables with some biochemical and clinical measurements in T2DM patients. In this study, forty one T2DM and forty three non-diabetes mellitus (non-DM) subjects, aged between 40-60 years and with normal weight, were enrolled. Fasting serum ghrelin and leptin were estimated by enzyme-linked immunosorbent assay (ELISA). In our results ghrelin was significantly increased, and leptin was significantly decreased, in T2DM pa
... Show MoreThe aim of the current research is to know the degree to which middle school teachers and female teachers in the southern border schools use electronic educational alternatives in the field of education from their point of view and its relationship to some variables, and to achieve this goal, a random sample of (200) teachers was selected in southern border schools, and a questionnaire was prepared to collect The data, as well as the descriptive approach was used to achieve this goal. T-test and analysis of variance were used for the statistical treatment. The results concluded that the educational courses provided to male and female teachers are not sufficient. It has also been concluded that the use of electronic educational alternativ
... Show MoreA detailed experimental study was devoted to the anodic oxidation of oxalic acid using manganese dioxide rotating cylinder anode with the objective to evaluate in a systematic way the effect on the oxalic acid oxidation process of several relevant parameters, including the presence of sodium chloride, the current density (J), the rotation speed, the temperature, and the initial concentration of oxalic acid. Thin manganese dioxide film on graphite substrate has been prepared by electrochemical oxidation from MnSO4-H2SO4 electrolyte. The morphology of this electrode was investigated by XRD, SEM, EDS and AFM techniques. The results show that a firm γ-structure of MnO2 film on graphite rod can be obtained successfully. The results indicate tha
... Show MoreThe synthesis , characterization and mesomorphic behaviour of new Nacyl , thiourea and imidazole derivatives which derived from corresponding Schiff bases are reported. All the synthesized compounds which contain flexible methylene group in the centre of the molecule did not show any liquid crystalline properties . The derivatives of N- acyl [III]e and thiourea [VI]e which contain biphenyl and all compounds with one phenyl in the centre of the molecule display liquid crystalline behaviour .While the imidazoles did not show any liquid crystalline properties except [V]b [V]e with biphenyl in the centre of the molecule . All th
... Show MoreComplexes of (Co2+, Ni2+, Cu2+, Zn2+, Cd2+ and Hg2+) with the ligand Ethyl cyano (2-methyl carboxylate phenyl azo acetate) (ECA) have been prepared and characterized by FTIR, (UV-Visible), Atomic absorption spectroscopy, Molar conductivity measurements and magnetic moments measurements. The following general formula has been suggested for the prepared complexes [M(ECA)2]Cl2 where M = (Co2+, Ni2+, Cu2+ ,Zn2+, Cd2+, Hg2+) and the geometry is octahedral.
In this study a new ligand ,(potassium 2-carbomethoxy amino-5-trithiocarbonate 1,3,4-thiadiazole) (L) has been prepared from 2-carbomethoxy amino-5-mercapto 1,3,4-thiadiazole with CS2 in alkali media . The product has been isolated and characterized by appropriate physical measurements, vibrational and electronic spectroscopy. The ligand was used to prepare a number of complexes with some metal ions Co(II), Ni(II) and Cu(II). These complexes have been characterized by FT-IR, UV-Vis spectra, molar conductivity, magnetic susceptibility, melting points and atomic absorption measurements. The nickel and copper complexes have an octahedral geometry while cobalt complex has a tetrahedral geometry. The nature of bonding between the metal ion
... Show MoreBackground: Chronic hyperglycemia is the most frequent diabetes-related metabolic disorder because of faulty insulin action or production. According to the WHO, osteoporosis is a progressive systemic skeletal disorder that decreases bone mass and micro architecture bone tissue, increasing bone fragility and fracture risk. Nervosa damage determines how much a diabetic's body is damaged. Objective: The current work aimed to examines age, BMI, HbA1c, fasting blood glucose, sclerostin, and lipid profiles (TC, TG, HDL-C, VLDL-C, and LDL-C) in Iraqi T2DM menopausal women with /without osteoporosis to detect biomarkers in such condition. Subjects and Methods: 120 subjects were included in this study. They were divided into 3 groups; Group 1 (N = 4
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