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101.
A selective dopamine determination using a nafion-coated clinoptilolite-modified carbon paste electrode in the presence of
ascorbic acid was studied. Both cyclic voltammetry (CV) and differential pulse anodic stripping voltammetry (DPASV) were used
for measurements of dopamine. To improve the selectivity of the clinoptilolite-modified carbon paste electrode in presence
of a high concentration of ascorbic acid, the electrode surface was coated with nafion membrane. Experimental parameters affecting
the determination of dopamine, including the clinoptilolite ratio, nafion membrane thickness, preconcentration time, preconcentration
solution pH, stripping solution pH and interferences are discussed. The developed sensor has a wide linear range, a low detection
limit, and good stability and reproducibility. The sensor offers a good alternative to existing analytical methods for dopamine,
permits a relatively short analysis time, and is simple, selective and inexpensive. 相似文献
102.
Yun Hau Ng Izan Izwan Hadi Nur Mohd Nazlan Mohd Muhid Halimaton Hamdan 《Journal of fluorine chemistry》2007,128(1):12-16
A series of amphiphilic fluorinated zirconia containing titanium was prepared by titanium impregnation followed by fluorination and alkylsilylation of zirconium oxide. Physical properties of the resulting samples were characterized by XRD analysis, UV-vis spectroscopy, BET surface area analysis and EDAX analysis. The effects of fluorine and alkylsilane groups on the samples were studied by the epoxidation of 1-octene with aqueous hydrogen peroxide. The epoxidation of alkenes is one of the most important methods of functionalizing simple hydrocarbons. The amphiphilic fluorinated catalysts were more active and more efficient than the conventional titania-silica and zirconia-silica mixed oxides in linear alkene epoxidation; enhanced by the presence of alkylsilane and fluorine groups in the catalysts. Modification with alkylsilane successfully induces the hydrophobic behavior of zirconia which is hydrophilic in nature; whereas fluorine was chosen for its electron-withdrawing effect which further activates the titanium active sites. 相似文献
103.
104.
Alraqa Shaya Y. Kaya Esra Nur Taşci Neşe Erbahar Dogan Durmuş Mahmut 《Journal of fluorescence》2022,32(5):1801-1813
Journal of Fluorescence - In this current study, the novel bis[4,5-(pyrene-2-yl)-3,6-(hexyloxy)] phthalonitrile (SPN) fluorophore has been successfully synthesized. Structural characterization of... 相似文献
105.
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
106.
We construct the inhomogeneous quantum groups with continuous parameters which leave the boson and fermion algebras of field
theory invariant. 相似文献
107.
Mat Mohamad Nur Hidayat Asmuin Nor Zelawati Md Basir Md Faisal Abbas Tehseen Mohd Kasihmuddin Mohd Shareduwan Goodarzi Marjan 《Journal of Thermal Analysis and Calorimetry》2021,143(3):2343-2354
Journal of Thermal Analysis and Calorimetry - In this paper, a numerical study was performed to examine the effect of divergent nozzle length of single-hose dry ice blasting on the development of... 相似文献
108.
109.
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
110.
Ridhuan Nur Syafinaz Mohamad Nor Noorhashimah Abdul Razak Khairunisak Lockman Zainovia Zakaria Nor Dyana 《Journal of Solid State Electrochemistry》2021,25(3):1065-1072
Journal of Solid State Electrochemistry - This work demonstrated the property enhancement of Pt nanodendrite (PtNDs)-decorated ZnO nanorods (ZnONRs) modified indium tin oxide (ITO) electrode for an... 相似文献