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 were investigated.
Background: Monocyte chemotactic protein-1 (MCP-1) is a chemokine expressed by inflammatory and endothelial cells. It has a crucial role in initiating, regulating, and mobilizing monocytes to active sites of periodontal inflammation. Its expression is also elevated in response to pro-inflammatory stimuli and tissue injury, both of which are linked to atherosclerotic lesions. Aim of the study: To determine the serum level of MCP-1 in patients with periodontitis and atherosclerotic cardiovascular disease in comparison to healthy control and evaluate the biomarker's correlations with periodontal parameters. methods: This study enrolled 88 subjects, both males and females, ranging in age from 36-66 years old, and divided into four groups: 1<
... Show MoreA new optoelectronic flow injection method is proposed for the determination of ferrous ions (Fe 2+ ) based on thiocyanate complexation to form a deep-red FeSCN 2+ complex.
An electrochemical sensor based on manganese dioxide nanorodMnO2and Graphene oxide (GO) functionalized with 4-amino, 3-substituted 1H, 1, 2, 4 Triazole 5(4H) thion (FGO)/MnO2Nanocompositewas developed for voltammetric determination of Tetracycline (TET).The working electrode WE of SPCE was modified bya drop casting method. X-ray powder diffractometer (XRD), scanning electron microscopy (SEM) and FT-IR were employed to characterize the synthesized FGO/MnO2. The determination of TET at the modified electrode was studied by cyclic voltammetry (CV) and differential pulse voltammetry (DPV) in the phosphate buffer solution (PBS).TET show sharp increase in the oxidation peaks in the pH 2.Voltammetric characteristics of TET (Epa, Ipa) were estimate
... Show MoreNew derivatives of Schiff bases were synthesized from the aldehyde derivative (Ma2) which was produced by reacting the mefenamic acid (Ma) with thionyl chloride to obtain the acid halide derivative (Ma1). Compound (Ma1) was dissolved in DMF and mixed with p-hydroxybenzaldehyde which was previously dissolved with pyridine to obtain the aldehyde derivative (Ma2). In the final step, derivatives of Schiff bases were synthesized by reacting the aldehyde (Ma2) with a number of different aromatic primary amines in the presence of glacial acetic acid to obtain the new derivatives Ma [3-10]. The new prepared compounds were characterized by melting points and with spectral data FT-IR, 13C-NMR and 1H-MNR (some of them). The vital effectiven
... Show MoreAzo-Schiff base compounds (L1 and L2) have been synthesized from the reaction of m-hydroxy benzoic acid with 1,5-dimethyl-3-[2-(5-methyl-1H-indol-3-yl)-ethylimino]-2-phenyl-2,3- dihydro-1H-pyrazol-4-ylamine and with 3-[2-(1H-indol-3-yl)-ethylimino]-1,5-dimethyl-2-phenyl- 2,3-dihydro-1H-pyrazol-4-ylamine. The free ligands and their complexes were characterized based on elemental analysis, determination of metal, molar conductivity, (1H, 13C) NMR, UV–vis, FT-IR, mass spectra and thermal analysis (TGA). The molar conductance data revealed that all the complexes are non-electrolytes. The study of complex formation via molar ratio in DMF solution has been investigated and results were consistent to those found in the solid complexes with a rat
... Show MoreUno de los rasgos más interesantes sobre España es la diversidad de sus lenguas, y aunque la mayoría de los españoles hablan español, pero una gran parte de la población es bilingüe y en algunas ocasiones, trilingüe. Hoy en día estas lenguas se usan y conviven juntas sin grandes problemas, aunque durante mucho tiempo esta convivencia ha sido muy complicada. Asi que el propósito de nuestro trabajo es enfocar la luz sobre la situación linguística actual de España.
Al estudiar la situación linguística de España encontramos que las lenguas son instrumentos vivos y dinámicos, inseparables de su propia historia, dos realidades, su pasado y su presente, que van conformando su propia estructura y su propio dominio lingüísti
Alloys from AgSb(SxSe1-x)2 with different compositions were prepared using quenching from the melt . This was done by put the appropriate amount of Ag, Sb,S and Se in an evaluated quartz ampoule , sealed and left at oven in temperature 1273 for 5 hours. Thin films with different composition were deposited by pulsed deposition technique PLD onto glass substrates at ambient temperature . This paper concerned on the investigate effect of composition on structural morphology, and electrical properties. The structure and morphology of the prepoared thin films were checked using X–ray diffraction and atomic force microscope. The D.C conductivity of the AgSb(SxSe1-x)2thin films with various x content was measured
... Show MoreThe Mannich base ligand was synthesized in an ethanol medium through a condensation reaction of 2-mercaptobenzimidazole and ciprofloxacin at room temperature. Subsequently, several metal complexes of this ligand were prepared. To characterize both the base ligand and the metal complexes, various techniques were employed, including elemental analysis, FT-IR spectroscopy, UV-Vis spectroscopy, molar conductivity measurements, magnetic moment determination, and melting point analysis. The results were shown that the metal complexes formed have the formula [Cr(L)2Cl2] Cl.H2O and [Rh(L)2(H2O)2] Cl3.H2O, where L= mannich base ligand. Based on spectroscopic analytical, coordination with metal ions involves the 'N' donor atom of mannich base
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