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).
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Abstract: Two different shapes of offset optical fiber was studied based on coreless fiber for refractive index (RI)/concentration (con.) measurement, and compare them. These shapes are U and S-shapes, both shapes structures were formed by one segment of coreless fiber (CF) was joined between two single mode (SMF) lead in /lead out with the same displacement (12.268µm) at both sides, the results shows the high sensitive was achieved in a novel S-shape equal 98.768nm/RIU, to our knowledge, no one has ever mentioned or experienced it, it’s the best shape rather than the U-shape which equal 85.628nm/RIU. In this research, it was proved that the offset form has a significant effect on the sensitivity of the sensor. Addi
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The present investigation is concerned for the purification of impure zinc oxide (80-85 wt %) by using petroleum coke
(carbon content is 76 wt %) as reducing agent for the impure zinc oxide to provide pure zinc vapor, which will be
oxidized later by air to the pure zinc oxide.
The operating conditions of the reaction were studied in detail which are, reaction time within the range (10 to 30 min),
reaction temperature (900 to 1100 oC), air flow rate (0.2 to 1 l/min) and weight percentage of the reducing agent
(petroleum coke) in the feed (14 to 30 wt %).
The best operating conditions were (30 min) for the reaction time, (1100 oC) for the reaction temperature, (1 l/min) for
the air flow rate, and (30 wt %) of reducing
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Background: Polymethyl methacrylate (PMMA) resin is extensively utilized in prosthodontics and orthodontics, particularly in fabricating artificial teeth, provisional crowns, denture bases, and orthodontic retainers. Aims: This study aimed to evaluate the effects of incorporating cerium oxide and polyether ether ketone nanoparticle (CP) composite into PMMA resin on transverse strength, impact strength, surface hardness, and denture base adaptation. Materials and Methods: A total of 120 PMMA specimens were divided into three groups based on the concentration of CP composite added to PMMA resin, with each group consisting of 40 specimens: a control group without fillers, group (A) containing 1% wt. of composite filler with a ratio of
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The present work involved synthesis of new thiozolidinone derivatives,These derivatives could be divided into three type of compounds; quinolin-2-one[V]a,b ,Schiff bases[VI]a,b and imide compounds[VII]a-d. The reaction p-Hydroxyacetophenone with thiosemicarbazide led to formation thiosemicarbazon compound [II], the reacted of thiosemicarbazone with chloro acetic acid in CH3CO2Na led to yield 4- thiazelidinone compound[III] in addition, thiosemicarbazide was POCl3 to [III] give [IV] compound used intermediates to synthesis new compounds of reacted with two type of coumarin in glacial acetic acid to give quinolin-2-one[V]a,b, The later compound refluxing with different benzaldehyde in dry benzene and glacial acetic acid give Schiff bases[VI]a
... Show MoreIn contrast to the classical antibacterial sulfa drugs that are unsubstituted or monosubstituted, our newly synthesized analogs were designed to obtain sulfonamide moiety containing disubstituted hetero nitrogen atom. These compounds were formed successfully by chlorosulfonation of acetanilide and the product was treated with different cyclic amines and finally amide hydrolysis was necessary to get agents that were analyzed for IR, UV, CHN, melting points and solubility. At last, we studied their antibacterial activity on certain types of bacteria and we noticed the inactivity due to possible steric factor. Principly, this means these products have no inhibiting action against the used microbes.