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201.
A. R. Moghadassi S. Masoud Hosseini D. Henneke A. Elkamel 《Journal of Thermal Analysis and Calorimetry》2009,96(1):81-84
Thermal conductivity is an important parameter in the field of nanofluid heat transfer. This article presents a novel model
for the prediction of the effective thermal conductivity of nanofluids based on dimensionless groups. The model expresses
the thermal conductivity of a nanofluid as a function of the thermal conductivity of the solid and liquid, their volume fractions,
particle size and interfacial shell properties. According to this model, thermal conductivity changes nonlinearly with nanoparticle
loading. The results are in good agreement with the experimental data of alumina-water and alumina-ethylene glycol based nanofluids. 相似文献
202.
Masoud Salavati-Niasari Seyed Nezamoddin Mirsattari Mehdi Bazarganipour 《Polyhedron》2008,27(18):3653-3661
The chemical modification of multi-wall carbon nanotubes (MWNTs) is an emerging area in material science. In the present study, an hydroxyl functionalized manganese(II) Schiff-base has been covalently anchored on modified MWNTs. The new modified MWNTs have been characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron (XPS), thermal analysis, UV–Vis, diffuse reflectance (DRS), FT-IR spectroscopy and elemental analysis. The results suggest that the symmetrical Schiff-base; N,N-bis(4-hydroxysalicylidene)-ethylene-1,2-diamine; H2[(OH)2-salen]; is a bivalent anion with tetradentate N2O2 donors derived from the phenolic oxygens and azomethine nitrogens. The formulae was found to be [Mn((OH)2-salen)] for the 1:1 non-electrolytic complex. The multi-wall carbon nanotubes covalently anchored manganese(II) complex ([Mn((OH)2-salen)]@MWNTs) catalyze the oxidation of cyclohexene with TBHP. Oxidation of cyclohexene catalyzed by this complex gave 2-cyclohexene-1-ol, 2-cyclohexene-1-one and 1-(tert-butylperoxy)-2-cyclohexene as the major products. The manganese(II) complex covalently anchored on MWNTs shows significantly higher catalytic activity than [Mn((OH)2-salen)]. The activity of the immobilized catalyst remains nearly the same after three cycles, suggesting the true heterogeneous nature of the catalyst. This catalyst is more selective towards 2-cyclohexene-1-one. 相似文献
203.
Mehdi Adib MohammadHosein Sayahi SomayehAali Koloogani Peiman Mirzaei 《Helvetica chimica acta》2006,89(2):299-303
The reactive 1 : 1 zwitterionic intermediates generated in situ from the reaction between a series of isocyanides and diaroylacetylenes were trapped by pyridine carbaldehydes to yield highly functionalized 5‐pyridylfuran‐2‐amines in good yields (82–93%). 相似文献
204.
Ali Sharifi Mehdi Barazandeh M. Saeed Abaee Mojtaba Mirzaei 《Journal of heterocyclic chemistry》2012,49(4):933-938
A medium consisting of K2CO3 and H2O in [omim][BF4] ionic liquid (IL) was used to synthesize N‐substituted 2H‐benzo[b][1,4]oxazin‐3(4H)‐one derivatives from their corresponding o‐aminophenols and 2‐bromoalkanoates. As a result, chemoselective formation of benzoxazinones in high yields has been observed at room temperature. After the reactions and separation of the products, the IL was recovered and successfully reused in subsequent reactions without significant loss of activity. 相似文献
205.
206.
In this investigation, a facile sonochemical route has been developed for the preparation of silver vanadium oxide (SVO) micro/nanorods by using silver salicylate and ammonium metavanadate as silver and vanadate precursor, respectively. Here, silver salicylate, [Ag(HSal)], is introduced as a new silver precursor to fabricate AgVO3 nanorods. The effect of numerous solvents and surfactants on the morphology and sonochemical formation mechanism of AgVO3 nanorods was studied. AgVO3 nanorods were characterized by SEM and TEM images, XRD patterns, FT-IR, XPS, and EDS spectroscopy. SEM, TEM, and XRD results showed that AgO nanoparticles were formed onto AgVO3 nanorods in the presence of ethanol, cyclohexanol, dimethylsulfoxide (DMSO), and acetone. By using polyethylene glycol (PEG-6000) and N,N-dimethylformamide (DMF) as organic additives, the thickness of AgVO3 nanorods decreased. 相似文献
207.
M. R. Ganjali Tahereh Poursaberi Fatemeh Basiripour Masoud Salavati-Niassari Mohammad Yousefi Mojtaba Shamsipur 《Analytical and bioanalytical chemistry》2001,370(8):1091-1095
A PVC membrane electrode based on a cadmium–salen (N,N′-bis-salicylidene-1,2ethylenediamine) complex as an anion carrier is described. The electrode has an anti-Hofmeister selectivity
sequence with a preference for thiocyanate at pH 1.5–11.0. It has a linear response to thiocyanate from 1.0 × 10–6 to 1.0 × 10–1 mol L–1 with a slope of 59.1 ± 0.2 mV per decade, and a detection limit of 7 × 10–7 mol L–1. This electrode has high selectivity for thiocyanate relative to many common organic and inorganic anions. The proposed sensor
has a fast response time of approximately 15 s. It was applied to the determination of thiocyanate in a milk sample.
Received: 1 December 2000 / Revised: 19 April 2001 / Accepted: 30 April 2001 相似文献
208.
Mohammad Hossein Keshavarz Sahar Belyani Seyyed Mohammad Reza Darbani Masoud Kavosh Tehrani 《无机化学与普通化学杂志》2019,645(16):1057-1061
Laser Induced Breakdown Spectroscopy (LIBS) method is introduced as a novel approach in this work to study catalyst deactivation of V2O5/γ‐‐Al2O3 for gas‐phase dehydration of glycerol and producing acrolein. The LIBS results of V2O5/γ‐Al2O3 samples are compared with those data that are obtained by Inductively Coupled Plasma Optical Emission Spectrometry (ICP‐OES). Experimental data of LIBS data specify that line intensities of vanadium are decreased by deactivation of V2O5/γ‐Al2O3 catalyst. A comparison between the results of LIBS test as well as ICP‐OES analysis shows that the amount of vanadium is decreased in the catalyst. Moreover, coke formation changes the surface of the catalyst. The results of deactivation of V2O5/γ‐Al2O3 are also compared with Pd/C catalyst deactivation. 相似文献
209.
Let R be a commutative ring with \(1\ne 0\) and the additive group \(R^+\). Several graphs on R have been introduced by many authors, among zero-divisor graph \(\Gamma _1(R)\), co-maximal graph \(\Gamma _2(R)\), annihilator graph AG(R), total graph \( T(\Gamma (R))\), cozero-divisors graph \(\Gamma _\mathrm{c}(R)\), equivalence classes graph \(\Gamma _\mathrm{E}(R)\) and the Cayley graph \(\mathrm{Cay}(R^+ ,Z^*(R))\). Shekarriz et al. (J. Commun. Algebra, 40 (2012) 2798–2807) gave some conditions under which total graph is isomorphic to \(\mathrm{Cay}(R^+ ,Z^*(R))\). Badawi (J. Commun. Algebra, 42 (2014) 108–121) showed that when R is a reduced ring, the annihilator graph is identical to the zero-divisor graph if and only if R has exactly two minimal prime ideals. The purpose of this paper is comparison of graphs associated to a commutative Artinian ring. Among the results, we prove that for a commutative finite ring R with \(|\mathrm{Max}(R)|=n \ge 3\), \( \Gamma _1(R) \simeq \Gamma _2(R)\) if and only if \(R\simeq \mathbb {Z}^n_2\); if and only if \(\Gamma _1(R) \simeq \Gamma _\mathrm{E}(R)\). Also the annihilator graph is identical to the cozero-divisor graph if and only if R is a Frobenius ring. 相似文献
210.
Molecular Diversity - This study describes the use of 3-aminotriazole, different aldehydes and N-methyl-1-(methylthio)-2-nitroethenamine as a ketene N,S-acetal in a three-component condensation for... 相似文献