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 annealing temperature (200–500 °C) effects of optical frequency response on the dielectric functions of sol–gel derived CuCoO
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Web application protection lies on two levels: the first is the responsibility of the server management, and the second is the responsibility of the programmer of the site (this is the scope of the research). This research suggests developing a secure web application site based on three-tier architecture (client, server, and database). The security of this system described as follows: using multilevel access by authorization, which means allowing access to pages depending on authorized level; password encrypted using Message Digest Five (MD5) and salt. Secure Socket Layer (SSL) protocol authentication used. Writing PHP code according to set of rules to hide source code to ensure that it cannot be stolen, verification of input before it is s
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Background: Dental implant considers a unique treatment option for the replacement of missing dentition. The new trend of implants is looking for materials which accelerate bone formation in bone implant interface and enhance osseointegration to provide immediate loading directly after placement and decrease the time period which is disturbs patients and uncomfortable. The aim of the study was to evaluate the effect of nano zirconium oxide (ZrO2) and nano hydroxyapatite (Hap) mixture coating of screw shaped commercially pure titanium (cpTi) implants on bond strength at the bone implant interface with torque removal test and histological analysis in comparison with non coated implants. Materials and methods: Forty screws were machined from c
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This study was carried out at the Dept. Hortic. and Land.Gard., Coll. Agric. Eng.Sci., University of Baghdad during fall season of 2019-2020, in order to evaluate the effect of nutrient solution type under hydroponic system (NFT) on growth, yield and quality of broccoli Brassica oleracea var.italica. Two experiments were carried out which were the standard solution experiment (Cooper) and the alternative solution experiment (ABEER) prepared from fertilizers. Results revealed that the type of solution used in the hydroponics system had non significant effect on the leaves content of N,K, Mg, Fe, Cu, B, Chlorophyll, leaves number, root length, weight of the main heads, number of side heads were not significantly affected. 13nt, refl
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This study attempts to address the importance of communicative digitization in the field of various arts for the sake of continuity of shopping and aesthetic, artistic and intellectual appreciation of artistic achievements by the recipient on various places of their residence in light of the COVID 19 crisis, and to highlight the importance of the plastic arts of the Iraqi painter exclusively and how it expresses in a contemporary way the environment or life reality in Iraq in light of this crisis. With all its implications affecting the life reality from various aspects and methods of its negative and positive employment. As for the research procedures, the researcher reviewed the research methodology represented by the descriptive ana
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