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91.
Didik Prasetyoko Zainab Ramli Salasiah Endud Hadi Nur 《Reaction Kinetics and Catalysis Letters》2005,86(1):83-89
Summary Titanosilicalite-1 (TS-1) in combination with sulfated zirconia efficiently catalyzes the epoxidation of 1-octene with aqueous hydrogen peroxide. The presence of both octahedral zirconium and sulfate species in the catalysts enhances the epoxidation rates. 相似文献
92.
93.
Mohammadhassan Vasheghani Ehsan Marzbanrad Cyrus Zamani Mohamed Aminy Babak Raissi Toraj Ebadzadeh Hadi Barzegar-Bafrooei 《Heat and Mass Transfer》2011,47(11):1401-1405
Thermal conductivity of α-Al2O3 was measured using hot wire method. α-Al2O3 (20 nm in size) was synthesized by microwave method for which, the results were compared with commercially available γ-Al2O3. Thermal conductivity of nanofluids was investigated considering, it is dependency on Al2O3 phase. It was observed that by adding 3 wt% of nano γ-Al2O3 and α-Al2O3 to the engine oil, thermal conductivity increases by 37 and 31%, respectively. The corresponding viscosity increase for the
same amount of nano γ-Al2O3 and α-Al2O3 were 36 and 38%, respectively. It was concluded that the differences in thermal conductivity originate from higher specific
surface area of γ-Al2O3 compared to the α-Al2O3 which is the result of porosity difference, obtained during the synthesis process. 相似文献
94.
A carbon-paste electrode modified with 2,7-bis(ferrocenyl ethyl)fluoren-9-one (2,7-BF) and carbon nanotubes (CNTs) was used for the sensitive and selective voltammetric determination of N-acetylcysteine (NAC). The mediated oxidation of NAC at the modified electrode was investigated by cyclic voltammetry (CV). Also, the values of catalytic rate constant (k), and diffusion coefficient (D) for NAC were calculated. Differential pulse voltammetry (DPV) of NAC at the modified electrode exhibited two linear dynamic ranges with a detection limit (3σ) of 52.0 nmol L−1. DPV was used for simultaneous determination of NAC and acetaminophen (AC) at the modified electrode, and quantitation of NAC and AC in some real samples by the standard addition method. 相似文献
95.
Boron nitride nanotubes (BNNTs) are semiconductors with a wide band gap. In comparison with carbon nanotubes (CNTs), BNNTs have higher chemical stability, excellent mechanical properties and higher thermal conductivity. In this paper, we study the effect of diameters and substituting B and N atoms of various zigzag BNNTs with Al, on structural and electronic properties of BNNTs in solid state using the density functional theory method. The results of calculations of density of states and band structure (band) showed that the band gap between the valence and conduction level increases as a result of the enhancement of tube diameter of BNNTs. Finally, the results showed that the electronic properties of the pristine BNNTs can be improved by doping Al atom in the zigzag configuration of tubes. 相似文献
96.
The electrooxidation of hydrochlorothiazide (HCT) at the surface of a benzoylferrocene modified multi-walled carbon nanotube paste electrode was studied using electrochemical approaches. Under the optimized conditions (pH 7.0), the square wave voltammetric peak current of HCT increased linearly with HCT concentration in the ranges of 6.0?×?10?7 to 3.0?×?10?4 M. The detection limit was 9.0?×?10?8 M HCT. The diffusion coefficient (D?=?1.75?×?10?5 cm2/s) and electron transfer coefficient (α?=?0.45) for HCT oxidation were also determined. The proposed sensor was successfully applied for the determination of HCT in human urine and tablet samples. 相似文献
97.
Muhammad Abbas Amanda M. Maceda Hamid R. Firouzi Zhifeng Xiao Hadi D. Arman Yanshu Shi Hong-Cai Zhou Kenneth J. Balkus Jr 《Chemical science》2022,13(48):14285
A new rare earth based two-dimensional coordination network and a three-dimensional metal–organic framework (MOF) have been synthesized using bicinchoninic acid (BCA) and yttrium(iii) ions. Yttrium dimer nodes are formed in the absence of a modulator, resulting in a 2D layered coordination network (Y–BCA-2D). The presence of fluorinating agents, e.g., 2-fluorobenzoic acid (2-FBA), 2,6-difluorobenzoic acid (2,6-DFBA), and perfluorohexanoic acid (PFHxA) result in μ3-F bridged metal hexaclusters (Y6F8) that form a three-dimensional MOF (Y–BCA-3D). It was found that Y3+ can break highly stable C–F bonds in aromatic and aliphatic fluorinated compounds. Single-crystal X-ray diffraction (SC-XRD) shows the presence of fluorine in the metal cluster which was confirmed by energy dispersive X-ray spectroscopy (EDS). High resolution X-ray photoelectron spectroscopy (XPS) and 19F Nuclear Magnetic Resonance (NMR) also verify the presence of metal–fluorine bonds in the cluster. The Y–BCA-3D MOF selectively adsorbs CO2 but not N2.The reaction of yttrium(iii) and linker makes a 2D metal–organic framework. The addition of fluorinated modulators result in fluorine extraction from modulators and makes a 3D-MOF. 相似文献
98.
Stelios Bekiros Samaneh Soradi-Zeid Jun Mou Amin Yousefpour Ernesto Zambrano-Serrano Hadi Jahanshahi 《Entropy (Basel, Switzerland)》2022,24(8)
This article is devoted to the determination of numerical solutions for the two-dimensional time–spacefractional Schrödinger equation. To do this, the unknown parameters are obtained using the Laguerre wavelet approach. We discretize the problem by using this technique. Then, we solve the discretized nonlinear problem by means of a collocation method. The method was proven to give very accurate results. The given numerical examples support this claim. 相似文献
99.
Lin Jiang Pauline M.G.van Deursen Hadi Arjmandi-Tash Liubov A.Belyaeva Haoyuan Qi Jiao He Vincent Kofman Longfei Wu Valery Muravev Ute Kaiser Harold Linnartz Emiel J.M.Hensen Jan P.Hofmann Grégory F.Schneider 《中国科学:化学(英文版)》2021,(6):1047-1056
Graphene as a two-dimensional material is prone to hydrocarbon contaminations,which can significantly alter its intrinsic electrical properties.Herein,we implem... 相似文献
100.
Reza Azadbakht Hassan Keypour Hadi Amiri Rudbari Ali Hossein Mohammad Zaheri Saeid Menati 《Journal of luminescence》2012,132(8):1860-1866
Two new macrocyclic systems (L1, L2) containing two emissive naphthalene were synthesized and characterized. The macrocycles were studied by 1H NMR, 13C NMR, COSY, HMQC, DEPT, microanalysis and mass spectroscopy. The influence of metal cations Na+, Cr3+, Mn2+, Fe3+, Co2+, Ni2+, Cu2+, Zn2+, Cd2+, and Hg2+ on the spectroscopic properties of the macrocyclic systems in acetonitrile/DMF 9:1 (v/v) mixtures were investigated by means of absorption and emission spectrophotometry. The macrocycle L1 was found to be as an effective fluorescence sensor for Zn2+ ions. Zn2+ and Cd2+ ions show the most effects on the fluorescence intensity of L2. 相似文献