In this study, several ionanofluids (INFs) were prepared in order to study their efficiency as a cooling medium at 25 °C. The two-step technique is used to prepare ionanofluid (INF) by dispersing multi-walled carbon nanotubes (MWCNTs) in two concentrations 0.5 and 1 wt% in ionic liquid (IL). Two types of ionic liquids (ILs) were used: hydrophilic represented by 1-ethyl-3-methylimidazolium tetrafluoroborate [EMIM][BF4] and hydrophobic represented by 1-hexyl-3-methylimidazolium hexafluorophosphate [HMIM][PF6]. The thermophysical properties of the prepared INFs including thermal conductivity (TC), density and viscosity were measured experimentally. The TC measurement showed an enhancement of about 3% for INF and of 1% MWCNT in [EMIM][BF4] at a temperature of 298.15 K: the TC was 0.186 W/m.K, the kinematic viscosity was 100 centistokes (cSt), and the density was 1.283 g.cm−3. On the other hand, the TC of 1% MWCNT in [HMIM][PF6] INF enhanced by 5%. In this case, at a temperature of 298.15 K, the TC was 0.158 W/m, the kinematic viscosity was 1200 cSt, and the density was 1.294 g.cm−3. Furthermore, the stability of the prepared INFs was measured using the zeta potential method after 28 days of preparation. The results show very good dispersion of the nanoparticles in the ILs for all the prepared INFs. The zeta potential was -69.30 mV and - 45.34 mV for 0.5% and 1% MWCNT in [EMIM][BF4], respectively. On the other hand, zeta potential was -51.78 and -46.67 mV for 0.5% and 1% MWCNT in [HMIM][PF6], respectively. According to the obtained results, the preferable INFs to use as a cooling medium at 25 °C was the INF of 1 wt% MWCNT in [EMIM][BF4], since it provides better thermophysical properties than the other prepared INFs.
Number of new polyester and polyamide are prepared as derivatives from 5,5`-(1,4-phenylene)-bis-(1,3,4-thiadiazole-2-amine) [C1], three series of heterocyclic compounds were synthesized.The first series includes the Schiff base [C2] prepared from the reaction between compound [C1] with p-hydroxy benzaldehyde in presence of acetic acid and absolute ethanol , then these derivatives have reaction with maleic anhydride , phthalic anhydride and sodium azide, respectively to obtain the compounds [C3-5] contaning (oxazepine and tetrazole) rings.The third series of compounds [C1-5] has transformed to their polymers [C6-15] by reaction with adipoyl chloride and glutroyl chloride , respectively. The reaction was followed by T.L.C and ident
... Show MoreA new ligand [N-(4-chlorobenzoyl amino) -thioxomethyl] valine (cbv) is synthesized by reaction of 4- chloro benzoyl iso thio cyanate with valine acid. The ligand is Characterized by elemental analysis ,FT-IR, and 13C 1H NMR spectra, some transition metals complex of this ligand were prepared and Characterized by FTIR , UV-Visible spectra , conductivity measurement's ,magnetic susceptibility , atomic absorption and determination of molar ratio (M:L), from results obtained , the following formula [M(cbv)2] where M+2 =Mn, Fe ,Co , Ni , Cu,Zn,Cd, and Hg and the proposed molecular structure for these complexes as tetrahedral geometry, except copper complex is have square planer geometry
A new ligand ( 4- methoxy benzoyl ) carbamothioyl ) Glycine (MCG) is synthesized by reaction of (4- methoxy benzoyl isothiocyanate) with Glycine(1:1). It is characterized by micro elemental analysis (C.H.N.S.), FT-IR, (UV-Vis) and 1H and 13CNMR spectra. Some metals ions complexes of this ligand were prepared and characterized byFT-IR,UV-Visible spectra, conductivity measurements, magnetic susceptibility and atomic absorption. From results obtained, the following formula [M(MCG)2] where M2+ = Mn, Co, Ni, Cu, Zn, , Cd and Hg, the proposed molecular structure for these complexes as tetrahedral geometry, except copper complex is has square planer geometry.
Discrete logarithms are applied in many cryptographic problems . For instance , in public key . and for construction of sets with disti nct sums of k-clcments. The purpose o r this paper
is to modify the method ol' informationl1·iding using discrete logarithms , introduce new properties of St - sets , uscdthe direct product of groups to construct cyclic group and finally, present modified method for knapsack &
... Show MoreThe study is based on the selective binding ability of the drug compound procaine (PRO) on a surface imprinted with nylon 6 (N6) polymer. Physical characterization of the polymer template was performed by X-ray diffraction and DSC thermal analysis. The imprinted polymer showed a high adsorption capacity to trap procaine (237 µg/g) and excellent recognition ability with an imprinted factor equal to 3.2. The method was applied to an extraction column simulating a solid-phase extraction to separate the drug compound in the presence of tinoxicam and nucleosimide separately and in a mixture of them with a recovery rate more than the presence of tinoxicam and nucleosimide separately and in a mixture of them with a recovery rate of more t
... Show MoreBackground: Acute appendicitis is a common surgical
problem that is associated with an acute-phase reaction.
Previous studies have shown that cytokines and acutephase proteins are activated and may serve as indicators for
appendicitis.
Objective: The aim of this study was to evaluate of serum
levels of interleukin-6 (IL-6) in correlation to the severity
to acute appendicitis.
Methods: This is a prospective study from December 2008
to March 2009 of patients who had appendectomy in
Department of Surgery, Al-Kindy Teaching Hospital -
Baghdad/Iraq. Serum for estimating levels of interleukin-6
(IL-6) was taken pre-operatively. Depending on the
macroscopic evidence during the operation and the
histopathol
A simple, rapid and sensitive spectrophotometric method has been proposed for the determination of La (III) using 3-hydroxy -4-(2-hydroxy-phenyl azo) naphthalene -1- sulfonic acid as a chromogenic reagent. This method is based on the formation of a red-pink colored complex, upon the reaction of La(III) with the reagent in an alkaline medium (pH= 9.50), having a maximum absorbance at 459 nm. Beer's law is valid in the concentration range 0.512 µg.ml-1 with a Sandell's sensitivity value of 0.0188 µg.cm-2 and molar absorptivity of 7376.12 L.mol-1.cm-1. The stoichiometric composition of the chelate is 1:3. The effect of the presence of different cations as interferants in the determination of La(III) under the given optimum conditions
... Show MoreFour Co(II), (C1); Ni(II), (C2); Cu(II), (C3) and Zn(II), (C4) chelates have been synthesized with 1-(4-((2-amino- 5‑methoxy)diazenyl)phenyl)ethanone ligand (L). The produced compounds have been identified by using spectral studies, elemental analysis (C.H.N.O), conductivity and magnetic properties. The produced metal chelates were studied using molar ratio as well as sequences contrast types. Rate of concentration (1 ×10 4 - 3 ×10 4 Mol/L) sequence Beer’s law. Compound solutions have been noticed height molar absorptivity. The free of ligand and metal chelates had been applied as disperse dyes on cotton fabrics. Furthermore, the antibacterial activity of the produced compounds against various bacteria had been investigated. F
... Show MoreFour Co(II), (C1); Ni(II), (C2); Cu(II), (C3) and Zn(II), (C4) chelates have been synthesized with 1-(4-((2-amino- 5‑methoxy)diazenyl)phenyl)ethanone ligand (L). The produced compounds have been identified by using spectral studies, elemental analysis (C.H.N.O), conductivity and magnetic properties. The produced metal chelates were studied using molar ratio as well as sequences contrast types. Rate of concentration (1 ×10 4 - 3 ×10 4 Mol/L) sequence Beer’s law. Compound solutions have been noticed height molar absorptivity. The free of ligand and metal chelates had been applied as disperse dyes on cotton fabrics. Furthermore, the antibacterial activity of the produced compounds against various bacteria had been investigated. F
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