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A series of new maleimide monomers substituted with Schiff base moieties were synthesized via acid-catalyzed condensation of 3-(N-maleimidyl)phenyl hydrazide with aromatic aldehydes and ketones. The newly synthesized monomers were introduced in free radical chain growth homopolymerization producing five new polymaleimides with pendent Schiff base moieties .The new monomers were introduced also in free radical chain growth copolymerization with acrylonitrile producing new five copolymaleimides containing pendent Schiff base moieties. The new homopolymers and copolymers are of great importance since incorporation of bulky Schiff base moieties in their repeating units exhibit them better solubility and processing properties which made them
... Show MoreIn this paper, a new third kind Chebyshev wavelets operational matrix of derivative is presented, then the operational matrix of derivative is applied for solving optimal control problems using, third kind Chebyshev wavelets expansions. The proposed method consists of reducing the linear system of optimal control problem into a system of algebraic equations, by expanding the state variables, as a series in terms of third kind Chebyshev wavelets with unknown coefficients. Example to illustrate the effectiveness of the method has been presented.
New, simple and sensitive batch and nFIA spectrophotometric methods for the determination of Vancomycin Hydrochloride in pure form and in pharmaceutical preparations were proposed, These method's were based on diazotization and coupling reaction between Vancomycin Hydrochloride and diazotized O-nitroaniline in alkaline medium to form Orange water-soluble dye that is stable and has a maximum absorbance at 465nm. Acalibration graph shows that aBeer's law is obeyed over the concentration range of 0.8-60 and 5-400 μg.mL-1 of Vancomycin Hydrochloride with detection limit's of 0.16 and 1.666 μg.mL-1 of Vancomycin Hydrochloride for batch and nFIA methods, respectively. The FIA procedure sample throughput was 80 h-1. All different chemicals an
... Show MoreThe effect of White Place Image ( Test Image ) A4 has been studied as a function of luminous intensity using the t tu un ng gs st te en n l la am mpp and web camera enet. It was found that the tungsten lamp gives almost even intensities for the three color band and lighting composite at low voltage .while at high voltage causes a fare from each other . The statistical characteristic(mean and stander deviation ) results for three colors composites RGB and lighting composites L showed that the mean and stander deviation increases with the increase of voltage possibly owing to the increase image resolution, which reflects the value of stander deviation for the blue band
... Show MoreA rapid and sensitive method for analysis of amino acid hydrolysates of nigella sativa L seed has been developed using O-phthaldialehyde(OPA ) as a pre-column derivatizing agent. OPA reagents in the presence of mercaptoethanol react rapidly with primary amino acids ( less than 60 sec.) to form isindole derivatives which easily separated with good selectivity on ODS column. Resolution of amino acid derivatives is carried out with a methanol gradient in 0.01 maqueous sodium acetate. pH 7.1 . The quantitation of amino acid derivatives is reproducible within an average relative deviation of + 1.4% the linearity for most amino acids were more than 0.9993 with detection limit of 0.2 ppm. 15 amino acid were detected in the analysis of
... Show MoreOptical properties of chromium oxide (Cr2O3) thin films which were prepared by pulse laser deposition method, onto glass substrates. Different laser energy (500-900) mJ were used to obtain Cr2O3 thin films with thickness ranging from 177.3 to 372.4 nm were measured using Tolansky method. Then films were annealed at temperature equal to 300 °C. Absorption spectra were used to determine the absorption coefficient of the films, and the effects of the annealing temperature on the absorption coefficient were investigated. The absorption edge shifted to red range of wavelength, and the optical constants of Cr2O3 films increases as the annealing temperature increased to 300 °C. X-ray diffraction (XRD) study reveals that Cr2O3 thin films are a
... Show MoreThis work includes the synthesis of some new five- seven heterocyclic rings derived from benzenesulfonylhydrazide as starting material. Its condensation with 4-methoxy and 4nitro benzaldehyde gives the Schiff bases (1a,b). Schiff bases were reacted with cyclic anhydrides given Oxazepine, Thiazepine derivatives(2,3,4 a,b)(seven membered ring) and with 2-mercapto benzoic acid gives thiazine derivatives (6a,b)(six membered ring) finally with thioglycolic acid give thiazolidine ring(five membered ring) scheme(3). The synthesized compounds have been characterized by melting points,FT-IR, 1H-NMR spectroscopy ,13CNMR and Elemental analysis. some of synthesized compounds were tested for their antibacterial activity
... Show MoreSynthesis of 2-mercaptobenzothiazole (A1) is performed from the reaction of o-aminothiophenol and carbon disulfide CS2 in ethanol under basic condition. Compound (A1) is reacted with chloro acetyl chloride to give compound (A2). Hydrazide acid compound (A3) is obtained from the reaction of compound (A2) with hydrazine hydrate in ethanol under reflux in the presence of glacial acetic acid .The reaction of hydrazide acid compound (A3) with ethyl acetoacetate gives pyrazole compound (A4). The new hydrazone compound (A5) was prepared from the reaction of compound (A3) with benzaldehyde. Reaction of compound
... Show MoreThe cost-effective removal of heavy metal ions represents a significant challenge in environmental science. In this study, we developed a straightforward and efficient reusable adsorbent by amalgamating chitosan and vermiculite (forming the CSVT composite), and comprehensively investigated its selective adsorption mechanism. Different techniques, such as Fourier-transform infrared spectroscopy (FTIR), zeta potential analysis, scanning electron microscopy (SEM), X-ray diffraction (XRD), and Brunauer, Emmett, Teller (BET) analysis were employed for this purpose. The prepared CSVT composite exhibited a larger surface area and higher mesoporosity increasing from 1.9 to 17.24 m2/g compared to pristine chitosan. The adsorption capabilities of the
... Show MoreNew polymers were prepared from a monomer (5-vinyl-1H-tetrazole), which was prepared from acrylonitrile with sodium azide in the presence of ZnCl2.Another monomer (Methyl acrylate) was also used. Co-monomers were polymerized usingBPO as initiator. The second step was the preparation of copoly acid hydrazide from the reaction of compound2 with hydrazine hydrate, followed by the reaction with carbon disulphide in the presence of KOH to obtain copoly (5-subs.-2-mercapto-1,3,4-thiadiazole). Next,compound4 was reacted with chloroacetyl chloride to yield compound4 5 which was reacted with (hydrazine hydrate , phenyl hydrazine and 2,4-di nitro phenyl hydrazine) as shown in scheme(1). Physical properties of all the prepared copolymers were chara
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