Transition metal complexes of Y(III), La(III) and Rh(III) with azo dye 2,4-dimethyl-6(4-nitro-phenylazo)-phenol derived from 4-nitroaniline and 2,4-dimethylphenol were synthesized. Characterization of these compounds has been done on the basis of elemental analysis, electronic data, FT-IR,UV-Vis and 1HNMR, as well as conductivity measurements. The nature of the complexes formed were studies following the mole ratio and continuous variation methods, Beer's law obeyed over a concentration range (1x10-4- 3x10-4). High molar absorbtivity of the complex solutions were observed. From the analytical data, the stoichiomerty of the complexes has been found to be 1:3 (Metal:ligand). On the basis of Physicochemical data octahedral geometries were assigned for the complexes.
Erbium, as optical probe, doped silicate sol-gel glass with
different Er concentrations was formed by wet chemical synthesis
method using ethanol, water and tetraethaylorthosilicate
[Si(OC2H5)4] precursor. Erbium ions were incorporated into silica
sol-gel matrix via dissolution of Erbium chloride solution into the
initial Si(OC2H5)4 precursor sol. Aluminum (Al) as a co-dopant was
added to the final precursor in the form of Aluminum chloride
(AlCl3) solution. The prepared samples were analyzed using atomic
absorption analysis, X-ray diffraction and spectroscopic tests. The
experimental results concerned with the transmission spectra suggest
that the final samples have a good transparency and homogeneity.
A
A new Turbidimetric method characterized by simplicity, accuracy and speed for determination of iron(III) in drug samples by continuous flow injection analysis. The method was based on the formation of complex for iron(III) with 8-hydroxyquinoline in presence of ammonium acetate as a medium for the formation of deep green precipitate and this precipitate was determined using homemade Linear Array Ayah-5SX1-T-1D continuous flow injection analyser. The optimum parameters were 2.6 mL.min-1 flow rate using H2O as a carrier, 1.9 mL.min-1 (14 mmol.L-1) ammonium acetate, 2.4 mL.min-1 (14 mmol.L-1) 8-hydroxyquinoline, 60 L sample volume and open valve for the purge of the sample segment. Data treatment shows that linear range 0.1-8.0 mmol.L-1
... Show MoreSulfamethoxazole (SMX) was added to P-N,N-dimethyl amino benzaldehyde (PDAB) by condensation reaction in acidic medium to form, a yellow colored dye compound which exhibits maximum absorption (λmax) at 450.5 nm. The concentration of (SMX) was determined spectrophotometrically. The optimum reaction conditions and other analytical parameters were evaluated. In addition to classical univariate optimization, design of experiment method has been applied in optimization of the variables affecting the color producing reaction. Beer’s law obeyed in the concentration range of 0.1-10 μg.mL-1 with molar absorptivity of 5.7950×104 L.mol-1.cm-1. The limit of detection and Sandell's sensitivity value were 0.078 μ
... Show MoreEssentiellement, la critique est l’âme de tous les domaines: artistique, scientifique, historique, … et littéraire. C’est la critique qui leur garantit l’existence et la continuité ; une telle puissance mérite d’être étudiée. La critique que nous allons aborder a pour objet l’étude de l’art littéraire. Cet art qui n’est que le recuit des faits et des expériences humains : Le critique à contempler ces expériences par une vision profonde susceptible de toucher les motifs les plus secrets ; il a à lire tout ce qui n’est pas écrit et à y ajouter sa culture pour en faire l’oeuvre critique.
Ainsi, critiquer, ce n’est pas attaquer, invectiver ni punir, mais c’est comprendre et analyser les oeuvre litté
Two derivatives of Iimidazolidin 4-one (IMID4) and Oxazolidin 5-one (OXAZ5), were investigated as corrosion inhibitors of corrosion carbon steel in sea water by employing the theoretical and experimental methods. The results revealed that they inhibit the corrosion process and their %IE followed the order: IMID4 (89.093%) > OXAZ5 (80.179%). The %IE obtained via theoretical and experimental methods were in a good agreement with each other. The thermodynamic parameters obtained by potentiometric polarization measurements have supported a physical adsorption mechanism which followed Langmuir adsorption isotherm. Quantum mechanical method of Density Functional Theory (DFT) of B3LYP with a level of 6-311++G (2d, 2p) were used to calculate
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Schiff base ligand (H2CANPT) was prepared by two steps: first, by the condensation of curcumin with 4-amino antipyrin produces4,4'-(((1E,3Z,5Z,6E)-1,7-bis(4-hydroxy-3- methoxyphenyl)hepta-1,6-diene-3,5-diylidene)bis(azanylylidene))bis(1,5-dimethyl-2-phenyl- 1,2-dihydro-3H-pyrazol-3-one) (CANP). Second, by the condensation of (CANP) with L-tyrosine produces2,2'-(((3Z,3'Z)-(((1E,3Z,5Z,6E)-1,7-bis(4-hydroxy-3-methoxyphenyl)hepta 1,6-diene-3,5-diylidene)bis(azanylylidene))bis(1,5-dimethyl-2-phenyl-1,2-dihydro-3-H-pyrazole- 4-yl-3-ylidene))bis(azanylylidene))bis(3-(4-hydroxyphenyl)propanoic acid) (H2CANPT). The resulted Schiff comported as hexadentate coordinated with (N4O2) atoms, then it was treated with some transition and non-transaction met
... Show MoreA new compounds of 2,4-substituted-1,3- thiazole containing amines [I] and [II], Schiff bases [IV] and [V], amides [VI]-[X],esters [XI] - [XIII], thiazolidinones [XIV]-[XVIII] and 1,3-oxazepines [XIX]-[XXV] were Synthesized and characterized by melting points, FTIR spectroscopy, elemental analysis, 1HNMR,13CNMR, dept135and Mass spectroscopy. The liquid crystalline properties of the synthesized compounds were verified by using hot-stage polarizing optical microscopy (POM) and differential scanning calorimeter (DSC). The compound [I] was found to be nematic textures (N). The first series of this study [II]n display only enantiotropic nematic phase when n=1-5 while the compounds with n =6-8 display two mesophasese smectic C(SmC) and nematic ph
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New thermally stable aromatic poly(amide-imide)s ( PAI1- PAI4 ) were synthesized from direct polycondensation reaction of Terephthalic acid and Phthalic acid with two new different diamine monomers derivatives of 1,2,4,5-tetracarboxilic benzene dianhydride as a second diacides in a medium consisting of triphenyl phosphite (TPP) in N-methyl-2pyrrolidone (NMP) / pyridine solution containing dissolved calcium chloride CaCl2. The polymerization reaction produced a series of novel poly(amide-imide) in high yield. The new monomers were characterized by FTIR, 1H-NMR spectroscopy. The resulting polymers were typically characterized by means of FT-IR, 1H-NMR spectroscopy, and solubility tests. Thermal properties of the poly(amide-imide)s were als
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