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Transesterification in the presence of aluminum chloride with long chain alcohols provides good yields of esters from the 2-ethylhexyl esters of 4-dimethylaminobenzoic and 4-methoxycinnamic acids. 相似文献
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We construct the inhomogeneous quantum groups with continuous parameters which leave the boson and fermion algebras of field
theory invariant. 相似文献
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Sami Ullah Humbul Suleman Muhammad Suleman Tahir Muhammad Sagir Shabbir Muhammad Abdullah G. Al-Sehemi Masood-ur-Rauf Zafar Firas A. Abdul Kareem Abdulhalim Shah Maulud Mohamad Azmi Bustam 《国际化学动力学杂志》2019,51(4):291-298
In this study, a new pressure drop method has been used to investigate the kinetics of carbon dioxide reaction with aqueous blend of 2-amino-2-ethyl-1,3-propanediol (AEPD) with piperazine (PZ). The blending of a small amount of PZ with AEPD has a significant effect on the observed rate constant, kobs. It was observed that kobs values of the blend increased more than twice than the summation of kobs values of individual alkanolamines. The reaction kinetics in this study were modeled by assuming a termolecular mechanism. The addition of 0.1 mol/L of PZ to 1 mol/L AEPD exhibited an observed rate constant, kobs of 8824.1 s−1, which is comparable to other alkanolamine mixtures. Hence, PZ/AEPD mixtures can be potentially used for rapid carbon dioxide capture. 相似文献
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Normawati M. Yunus M.I. Abdul Mutalib Zakaria Man Mohamad Azmi Bustam T. Murugesan 《The Journal of chemical thermodynamics》2010,42(4):491-495
The thermophysical properties of 1-alkylpyridinium bis(trifluoromethylsulfonyl)imide, [Cnpy][Tf2N] ionic liquids where n = 4, 8, 10, or 12 have been determined. Density ρ, and dynamic viscosity η, were determined at T = (293.15 to 353.15) K and refractive index nD, was measured at T = (293.15 to 333.15) K. Empirical correlations are proposed to represent the present experimental results. The values of the coefficient of thermal expansion were calculated from the experimental density values. The thermal decomposition temperature, Td was also determined using thermogravimetric analyzer (TGA) at a heating rate of (10 and 20) K · min?1. 相似文献
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Siti Nuurul Fatimah Hasim Muhammad Azmi Abdul Hamid Roslinda Shamsudin Azman Jalar 《Journal of Physics and Chemistry of Solids》2009,70(12):1501-1504
ZnO thin films have been successfully synthesized by thermal evaporation of pure zinc at 900 °C under the flow of different percentages of argon and oxygen gases. The films were characterized by X-ray diffraction (XRD), variable pressure scanning electron microscopy (VPSEM), energy dispersive X-ray spectroscopy (EDS) and UV–vis spectroscopy. The aim of this paper is to study the influence of the oxygen percentage on the structural and morphological properties of the ZnO films. VPSEM results show that very thick needle structures were produced at high oxygen percentages. EDS results revealed that only Zn and O are present in the sample, indicating a composition of pure ZnO. XRD results showed that the ZnO synthesized under different quantities of oxygen were crystalline with the hexagonal wurtzite structure. UV–vis spectroscopy results indicated that the optical band gap energies from the transmission spectrum are between 3.62 and 3.69 eV for ZnO thin films. 相似文献
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A kinetic spectrophotometric method has been described for the determination of metoprolol tartrate in commercial dosage forms. The procedure is based on the reaction of the drug with 1‐chloro‐2, 4‐dinitrobenzene (CDNB) in dimethylsulfoxide (DMSO) at 100 ± 1 °C. The reaction is investigated by measuring the change in absorbance with time at 420 nm. Fixed‐time (ΔA) and equilibrium methods are chosen for obtaining the calibration curves. Both calibration curves were found to be linear over the concentration range of 5‐60 μg mL?1. The regression analysis of calibration data resulted in the linear regression equations of ΔA = ?1.608 × 10?4 + 3.96 × 10?3 C and A = 7.31 × 10?4 + 1.90 × 10?2 C for fixed time (ΔA) and equilibrium methods, respectively. The limit of detection (LOD) for fixed time and equilibrium methods are 1.16 and 0.415 μg mL?1, respectively. The method has been successfully applied to the quantitation of metoprolol tartrate in commercial dosage forms. Statistical comparison of the results shows that there is no significant difference between the proposed methods and El‐Ries's spectrophotometric method. 相似文献
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Azmi Hanna 《Archiv der Mathematik》1974,25(1):39-39
Ohne ZusammenfassungDer Autor ist Humboldt-Stipendiat zur Zeit am Mathematischen Institut der Universität Heidelberg. 相似文献