This study involved preparation of Graphene oxide (GO) and reduced graphene oxide (RGO) using Hummer method and chemical method respectively. These carbon nanomaterials were used as starting material to make novel functionalize with thiocarbohydrazide (TCH) which was prepared by reacting CS2 with hydrazine to form GO or RGO- 4-amino,5-substituted 1H,1,2,4 Triazole 5(4H) thion (ASTT) ,(GOT) and( RGOT) respectively via cyclocondensation reaction. Also MnO2 nanorod was prepared to form hybridized with GOT and RGOT. A commercial multiwall carbon nanotube (MWCNT) and functionalization with carboxylic groups' (f-MWCNT) and its nanocomposite with GOT were also prepared. All carbon nanomaterials were characterized with different techniques such as Fourier transform infrared (FT-IR), X-ray diffraction (XRD), atomic force microscope (AFM) scanning electron microscope (SEM) and elemental analysis. XRD showed presence diffraction peak at 11.95 for GO and this diffraction disappeared for RGO. Diffraction peak of crystal planes for MnO2 matched well with standard data. The diameter of MnO2 nanotubes was determined using Debye scherrer equation and found to be 11.6nm corresponding with AFM image. The AFM images proves the growth of MnO2 nanotubes from the MnO2 nano spherical shape these images are very rare in the scientific literature. The real permittivity (ε'), imaginary permittivity (ε") and a.c conductivity (S.m-1) of all nanomaterials were measured by LCR meter at frequencies ranging from 100Hz to 100 KHz. The result showed the values of the real permittivity for RGO higher than GO at all frequencies while RGOTM have lower values of real permittivity at low frequency due to presence of MnO2 nanorods which affected the accumulation of charges. The imaginary permittivity of f-MWCNT-GOT and RGO were at low frequency higher than the real values due to their high conductivity. Also imaginary permittivity of f-MWCNT-GOT nanocomposites at all frequencies higher than real which have negative values at frequencies in range 400 to 4KHz .a.c conductivity for RGO and f-MWCNT-GOT nanocomposite have higher values compared with all prepared nanomaterial, at the same time the modified WE with f-MWCNT-GOT nanocomposite show the best detection limits in comparison with other prepared modified WE. Also the prepared nanomaterials were used to study novel sensing system and develop electrochemical sensor capable of detecting some of antibiotics such as Ampicillin (AMP), Amoxilline (AMOX) which have β-lactam ring and Tetracycline (TET) which contains four hydrocarbon rings using cyclic voltammetry (CV) technique via modification of the working electrode of the SPCE with the prepared nanomaterial by deposition process. f-MWCNT-GOT/SPCE nanocomposite showed higher electrochemical reaction response and lower limit of detection. The working electrodes surfaces were studied with AFM and SEM techniques. The value of apparent heterogeneous electron transfer rate constant (ks) was determined using the value of electron transfer coefficient (α) and the result showed that f-MWCNT-GOT/SPCE showed higher (ks).
The aim of the work is the synthesis and characterization of the tridentate Schiff base (HL) containing (N and O) as donor atoms type (ONO). The ligand is: (HL) phenyl 2-(2-hydroxybenzylidenamino)benzoate . This ligand was prepared by the reaction of (phenyl 2-aminobenzoate) with salicylaldehyde under reflux in ethanol and few drops of glacial acetic acid which gave the ligand (HL). The prepared ligand was characterized by (FT IR,UV–Vis) spectroscopy, Elemental analysis of carbon, hydrogen and nitrogen (C.H.N.) and melting point. The ligand was reacted with some metal ions under reflux in ethanol with (1 metal :2 ligand )mole ratio which gave complexes of the general formula: [M(L)2]Cl , M = Cr III La III and , Pr III Products were found
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Epoxy resins were modified by some thermosetting materials using unsaturated polyesters which were cured with styrene , MMA ,and MA . When unsaturated Polyester ( as thermosetting material ) was used , and cured with styrene showed better results than acrylic monomers . Thermal stability rised on modification of epoxy resins with unsaturated polyester . The new formulation had converted the epoxy resin from hard brittle material to hard and tough material .
Thermal analysis were studied using ( DSC ) and physicomechanical characteristics were measured .
Abstract: In the present work, the heat transfer of Nano Aluminum Oxide -NAO- has been studied practically to define the appropriate insulation conditions. This study focuses on finding of the amount of heat transfer through a glass substrate that is coated with nanoalumina doped on PMMA matrix. The optical and thermal properties were systematically investigated. The density of heat flow rate, was calculated in the range values (240-260) W/m2 while the optimum values confine between (250-260) W/m2 at temp. (25-35)Co. The results showed that the thermal insulation of the sample was significantly enhanced at temp. (30-50)Co. The simulated net heat transfer through window decreased linearly with incr
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This research aims to compare Bayesian Method and Full Maximum Likelihood to estimate hierarchical Poisson regression model.
The comparison was done by simulation using different sample sizes (n = 30, 60, 120) and different Frequencies (r = 1000, 5000) for the experiments as was the adoption of the Mean Square Error to compare the preference estimation methods and then choose the best way to appreciate model and concluded that hierarchical Poisson regression model that has been appreciated Full Maximum Likelihood Full Maximum Likelihood with sample size (n = 30) is the best to represent the maternal mortality data after it has been reliance value param
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In this work, porous silicon gas sensor hs been fabricated on n-type crystalline silicon (c-Si) wafers of (100) orientation denoted by n-PS using electrochemical etching (ECE) process at etching time 10 min and etching current density 40 mA/cm2. Deposition of the catalyst (Cu) is done by immersing porous silicon (PS) layer in solution consists of 3ml from (Cu) chloride with 4ml (HF) and 12ml (ethanol) and 1 ml (H2O2). The structural, morphological and gas sensing behavior of porous silicon has been studied. The formation of nanostructured silicon is confirmed by using X-ray diffraction (XRD) measurement as well as it shows the formation of an oxide silicon layer due to chemical reaction. Atomic force microscope for PS illustrates that the p
... Show MoreThe electrochemical polymerization of the monomer sulfanilamide (SAM) in an aqueous solution at room temperature produces polysulfanilamide (PSAM). The Fourier Transform Infrared spectroscopy (FTIR) was used to investigate the properties of the prepared polymer layer that generated on the stainless steel (St.S) surface (working electrode) and Atomic Force Microscope (AFM) was used to characterize the morphology, topology, and detailed surface structure of polymer layer that generated on the surface. The corrosion behavior of uncoated and coated St.S were evaluated by using the electrochemical polarization method in a 0.2 M HCl solution and a temperature range of 293–323 K, the anticorrosion action of the polymer coating on stainless steel
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(4)
A new derivatives of Schiff bases connected with 5H-thiazolo[3,4-b][1,3,4]thiadiazole ring 5a-c were prepared via many reactions starting by treating 1,4-phenylene diamine 1 with chloroacetylchloride to prepared compound 2, then reaction with p-hydroxybenzaldehyde to synthesize compound 3 then, this was reacted with thioglycolic acid and thiosemicarazide to giveN,N-(1.4-phenylene)bis(2-(4-(2-amino-5Hthiazolo[4,3-b][1,3,4]thiadiazol-5-yl)phenoxy)acetamide) 4. Compound 4 was treated with different aromatic aldehydes to give a new derivatives of Schiff bases containing 5H-thiazolo[3,4-b][1,3,4]thiadiazole ring 5a-c. The synthesized compounds were characterized using FTIR spectrophotometer and 1H NMR spectroscopy and the biological activity of
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(2)
In this study, a Hydroxyapatite (HA) coating was prepared on a titanium implant by an electrochemical deposition process. The titanium pre-treatment by anodizing in 1.65 mol/L sulfuric acid with (10V) at room temperature. The deposition was all conducted at a constant voltage of 6.0 V, for 1 h at room temperature. The coatings thus prepared were characterized with Fourier transform infrared spectroscopy (FTIR) and thickness of the coated layer.The electrochemical deposition of HA occurred on the titanium as a cathode. Coated titanium by HA after anodizing revealed a good corrosion protection efficiency even at a temperature ranged (293-323) K in artificial saliva. Activation energy and pre-exponential factor (kinetic parameters) were calcul
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(13)
The concept of TQM is based on one of the concepts that combine administrative and innovative methods. The aim of the research is to demonstrate the dimensions of TQM in enhancing the satisfaction of the taxpayers through a survey of a sample of officials in the General Authority for Taxation and 50 officials. In the collection of data and information, and the results were analyzed using the SPSS program to find the most important compounds and factors in he method of analysis.
The research problem was represented by the non-application of the General Authority for Taxation to the entrances and modern practices in the administrative work. The results of some of the complications that accompany the tax accounting process, which af
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