The zeolite's textural properties have a significant effect on zeolite's effectiveness in the different industrial processes. This research aimed to study the textual properties of the NaX and FeX zeolites using the nitrogen adsorption-desorption technique at a constant low temperature. According to the International Union of Pure and Applied Chemistry, the adsorption-desorption isotherm showed that the studied materials were mixed kinds I/II isotherms and H3 type hysteresis. The Brunauer-Emmett-Teller isotherm was the best model to describe the nitrogen adsorption-desorption better than the Langmuir and Freundlich isotherms. The obtained adsorption capacity and Brunauer-Emmett-Teller surface area values for NaX were greater than FeX. According to the Kelvin equation, Barrett, Joyner, and Halenda model was used to determine pore size distribution, diameter, and average pore volume for the selected zeolites. The pore size distribution for NaX was wider than FeX zeolites, the pore diameter for NaX was less than FeX, and the average pore volume for FeX was greater than the value of NaX average pore volume. The comparative study was carried out with the previous studies, and the comparison showed that the textual properties of the modified zeolites agreed with other studies.
The modern steer-by-wire (SBW) systems represent a revolutionary departure from traditional automotive designs, replacing mechanical linkages with electronic control mechanisms. However, the integration of such cutting-edge technologies is not without its challenges, and one critical aspect that demands thorough consideration is the presence of nonlinear dynamics and communication network time delays. Therefore, to handle the tracking error caused by the challenge of time delays and to overcome the parameter uncertainties and external perturbations, a robust fast finite-time composite controller (FFTCC) is proposed for improving the performance and safety of the SBW systems in the present article. By lumping the uncertainties, parameter var
... Show MoreIn this paper, an adaptive active disturbance rejection control is newly designed for precise angular steering position tracking of the uncertain and nonlinear SBW system with time delay communications. The proposed adaptive active disturbance rejection control comprises the following two elements: (1) An adaptive extended state observer and (2) an adaptive state error feedback controller. The adaptive extended state observer with adaptive gains is employed for estimating the unmeasured velocity, acceleration, and compound disturbance which consists of system parameter uncertainties, nonlinearities, exterior disturbances, and time delay in which the observer gains are dynamically adjusted based on the estimation error to enhance est
... Show MoreM(II) Ions using amino acid L- proline as a primary ligand and either Nicotinamide or 8- hydroxyqinoline as secondary ligand, respectively: a. The mixed ligand complexes of composition,[M(pro)2(na)2]. b. The mixed ligand complexes of composition , Na[M(pro)2(Q)]. Where proline (C5H9NO2) symbolized as pro H , Nicotinamide (C6H6N2O) symbolized as (NA) , 8- hydroxyqinoline, (C9H7NO2) symbolized as (8-HQ). The ligands and the metal chlorides were brought into reaction at room temperature (37ºc) in ethanol as solvent .The reaction required the following molar ratios [(1:2:2) metal:2NA:2pro-] and [(1:1:2) metal:Q:2pro-] with M+2 ions, where M = [Mn (II), Co(II), Ni(II), Cu(II), Zn(II), Cd(II) and pd(II)]. Products were found to be solid crystall
... Show MoreProduction and characterization of methionine γ- lyase from Pseudomonas putida and its effect on cancer cell lines
The work involves synthesis of new Schiff bases ([V] a, b and [VI] a, b), pyrazoles [VII] a, b and pyrazolines [VIII] a, b derivatives containing isoxazoline unit starting with chalcones. 4-bromoacetophenone was reacted with 4-hydroxybenzaldehyde or 4-hydroxyacetophenone was reacted with 4-bromobenzaldehyde in basic medium to give chalcone by Claisen-Schemidt reaction. The chalcons [I] a, b was reacted with hydroxylamine hydrochloride to form isoxazolines [II] a, b. which were reacted with ethyl chloro acetate in basic medium to get ester compounds [III] a, b. The condensation new ester [III] a, b with hydrazine hydrate80% yieldedacid hydrazide [IV] a, b. The later compound refluxing with 4-substituted benzaldehyde in dry benzene to give Sc
... Show MoreNew metal complexes of some transition metal ions Co(II), Cu(II) , Cd(II) and Zn(II) were prepared by their reaction with previously prepared ligands HLI= (P-methyl anilino) phenyl acetonitrile and HLII = (P-methyl anilino) –P– chloro phenyl acetonitrile . The two ligands were prepared by Strecker’s procedure which includ the reaction of p- toluidine with benzaldehyde and P- chlorobenzaldehyde respectively. Structures were proposed depending on atomic absorption , i.r. and u.v.visible spectra in addition to magnetic susceptibility and electrical conductivity measurements.
The article presents the synthesis and liquid crystalline properties of some of new bent and linear core compounds containing a 1,3,4-oxadiazole, piperazine and thiazolidin-4-one rings as a central core. The new synthesized compounds were characterized by elemental analysis and FTIR, ¹HNMR and mass spectroscopy). The liquid crystalline properties were studied by polarized optical microscopy and differential scanning calorimetry. All Schiff bases compounds with 1,3,4-oxadiazole and piprzaine ring in central core presented liquid crystalline properties. The liquid crystallinity of compounds containing 1,3,4-oxadiazole and thiazolidin-4-one rings as a central core were found depending on the type of terminal substituents.
Six membered heterocyclic derivatives (dihydroquinazoline-4-one and 1,3-benzothiazine-4-one (6–15)) were synthesized by cyclization reaction of Schiff bases (1–5) with anthranilic acid and o-mercaptobenzoic acid in oily bath. Prepared compounds was characterized by FTIR, 1H NMR, 13C NMR, mass spectroscopy and elemental analysis to confirm structure of synthesized derivatives. Heterocyclic compounds are of interest for scientific research due to important antioxidant properties; Compounds 10, 12, and 15 appeared good results by scavenging free radicals. Investigation of microbial activity to synthesized compounds 6–15 showed that compounds 6, 10, and 11 demonstrate the highest inhibition zone.