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131.
ABSTRACTIn this paper some new classes of two-variable orthogonal functions by using Fourier transforms of two-variable orthogonal polynomials are introduced. Orthogonality relations are obtained by using the Parseval identity. Recurrence relations for new families of orthogonal functions are also presented. 相似文献
132.
Sehrish Malik Adnan Jahangir 《Mathematical and Computer Modelling of Dynamical Systems: Methods, Tools and Applications in Engineering and Related Sciences》2020,26(4):344-356
ABSTRACT In this article, we explore the three-dimensional boundary-layer flow over an exponentially stretching surface in two parallel ways. Constitutive equations of a second-grade fluid are used. Instead of classical Fourier’s law, Cattaneo–Christov heat flux model is employed for the formulation of the energy equation. This model can predict the effects of thermal relaxation time on the boundary layer. The resulting partial differential equations are reduced into ordinary differential equations by similarity transformations. Homotopy Analysis Method (HAM) is employed to solve the non-linear problem. Physical impact of emerging parameters on the momentum and thermal boundary-layer thickness are studied. 相似文献
133.
Muhammad Asim Farooq Md Aquib Sana Ghayas Rabia Bushra Daulat Haleem Khan Amna Parveen Bo Wang 《先进技术聚合物》2019,30(9):2183-2191
Natural polymers have been extensively utilized in the past decades due to their outstanding features. Among these natural excipients, protein‐based polymers have superb features owing to their high drug binding capacity and biodegradability. Whey protein is a versatile protein‐based vehicle for drug delivery systems. It has been shown to be nontoxic, biocompatible, and biodegradable. Therefore, it has been considered as an ideal biomaterial for the design of advanced drug delivery systems. Protein‐based cargo acts as synthetic polymers counterpart for innovative delivery systems. The current review is mainly focused on application of whey proteins as an emerging carrier in drug delivery systems, achieved during the past. 相似文献
134.
The three possible isomeric structures of the sabandin coumarin were published by Reyes and Gonzalez in 1970. We have isolated two of these isomers sabandins A and B from Artemisia scoparia (Asteraceae) and distinguished by NOE difference NMR measurements. 相似文献
135.
M.?SharifEmail author Rabia?Saleem Sidra?Mohsaneen 《International Journal of Theoretical Physics》2016,55(7):3260-3273
In this work, we study the effects of generalized dissipative coefficient on the slow-roll inflation driven by non-Abelian gauge field minimally coupled to gravity. The dynamics of warm intermediate and logamediate inflationary models during weak and strong dissipative regimes is analyzed. In both cases, we explore effective scalar potential, slow-roll parameters, scalar and tensor power spectra, scalar spectral index and tensor to scalar ratio under slow-roll conditions. We conclude that our gauge-flationary model with generalized dissipative coefficient remains consistent with the recent data for dissipative parameter m = 3 and m = 1 for weak and strong dissipative eras, respectively. 相似文献
136.
3-Substituted N-Boc-1,2-dihydroisoquinolines 2 can be functionalized at the 1-position via lithiation and subsequent electrophilic trapping. The resulting products 3 can be deprotected and oxidized to afford the corresponding 1,3-disubstituted isoquinolines 5 . Deprotection of dihydroisoquinoline 3k followed by sodium borohydride reduction affords the cis-1,3-disubstituted tetrahydroisoquinoline 11 . The 1,3-disubstituted N-Boc-1,2-dihydroisoquinoline 3g is efficiently alkylated at the 1-position to give 1,1,3-trisubstituted analogs 12 . 相似文献
137.
Mostafa K. M. Rabia 《Monatshefte für Chemie / Chemical Monthly》1992,123(11):977-982
The voltammetric reduction mechanism of 2-(4-dimethylaminostyryl)-1-ethyl pyridinium iodide at the hanging dropping mercury electrode has been studied in N,N-dimethylformamide solution containing 0.1 mol dm–3 tetraethylammonium perchlorate. The depolarizer is reduced via a single diffusion-controlled irreversible two-electron cyclic voltammetric wave. The wave is attributed to the reduction of the azomethine bond of the pyridinium nucleus. Cyclic voltammetric studies indicate that the cv wave follows an ECE mechanism. The chemical reaction is proposed to be a protonation.
Voltammetrische Reduktion von 2-(4-N,N-Dimethylaminostyryl)-1-ethyl-pyridiniumjodid inDMF
Zusammenfassung Es wurde der voltammetrische Reduktionsmechanismus von 2-(4-N,N-Dimethylaminostyryl)-1-ethyl-pyridiniumjodid in Dimethylformamid-Lösung mit einem Tetraethylammoniumperchlorat-Gehalt von 0.1 mol dm–3 an der tropfenden Quecksilberelektrode untersucht. Der Depolarisator wird über eine einzige diffusionskontrollierte irreversible Zweielektronenwelle reduziert. Diese Welle wird der Reduktion der Azomethinbindung des Pyridinium-Kerns zugeordnet. Cyclische voltammetrische Untersuchungen zeigen, daß die CV-Welle einem ECE-Mechanismus folgt. Als chemische Reaktion tritt Protonierung ein.相似文献
138.
Liza Saher Malika Makhloufi-Chebli Leila Dermeche Samia Dermeche Baya Boutemeur-Khedis Cherifa Rabia Maamar Hamdi Artur M.S. Silva 《Tetrahedron》2018,74(8):872-879
A series of novel 10-(4-hydroxy-6-methyl-2-oxo-2H-pyran-3-yl)-3-methyl-1H,10H-pyrano[4,3-b]chromen-1-ones were synthesized by a pseudo-three-component reaction of 4-hydroxy-6-methyl-2-oxo-2H-pyran-2-one (TAL) with 2-hydroxyarylaldehydes using different acids as catalysts and solvents. The approach relies on a regioselective cascade reaction involving two molar equiv of the TAL iteratively acting as active methylene in a Knoevenagel condensation and in a Michael addition. The antioxidant activity of the synthesized compounds were determined using the DPPH scavenging assay, being the results dependent on the nature and number of chromone substituents. The compound bearing an ortho-dihydroxy (catechol) moiety showed excellent activity at lower concentrations, while derivatives bearing alkoxy groups as substituents present pro-oxidant activity. 相似文献
139.
POLAG computer programme was employed for processing convoluted-deconvoluted cyclic voltammetric data to study cadmium(II)-L-histidinate system. This was performed in 0.1 mol/dm(3) NAClO(4) aqueous solution at different pH's at 298K. The results show that the reduction of cadmium(II) and its complexes proceeds via a reversible and diffusion-controlled wave of two electrons at the entire range of pH. The system was studied at two ranges of pH (6.73-7.44 and 8.53-8.92). It was evident that the system at the first range of pH is well described by the presence of a mixture of binary complexes, [Cd(HisO.H)], [Cd(HisO.H(2))(2)] and a ternary one [Cd(HisO.H)(HisO.H(2))]. For the second pH range, it was revealed that the most likely model corresponds to the presence of a mixture of [Cd(HisO)(2)] and [Cd(OH)] species. The overall stability constants were computed. The structure of the detected complexes was discussed on the basis of ligating sites of histidine. 相似文献
140.
Naeem Nida Khoja Asif Hussain Butt Faaz Ahmed Arfan Muhammad Liaquat Rabia Hasnat Amin Ul 《Research on Chemical Intermediates》2022,48(5):2007-2034
Research on Chemical Intermediates - In this study, biomass fly ash (BFA)-supported Ni/CaO catalyst was synthesized, characterized and evaluated for partial oxidation of methane (POM) in a fixed... 相似文献