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1.
Elham Doroodchi Thomas Michael Evans Behdad Moghtaderi 《Journal of nanoparticle research》2009,11(6):1501-1507
This article provides critical examinations of two mathematical models that have been developed in recent years to describe
the impact of nano-layering on the enhancement of the effective thermal conductivity of nanofluids. Discrepancy between the
two models is found to be an artefact of an incorrect derivation used in one of the models. With correct formulation, both
models predict effective thermal conductivity enhancements that are not significantly greater than those predicted by classical
Maxwell theory. This study indicates that nano-layering by itself is unable to account for the effective thermal conductivity
enhancements observed in nanofluids. 相似文献
2.
Dr. Behdad Aghelnejad Prof. Geoffrey Bodenhausen Dr. Philippe Pelupessy 《Chemphyschem》2022,23(3):e202100786
Diffusion processes can be followed directly by recording one-dimensional images of a selected slice at variable intervals after selective inversion of the magnetization. The resulting diffusion coefficients of H2O and DMSO are consistent with earlier studies at different temperatures, obtained by monitoring the attenuation of NMR signals as a function of the gradient amplitude in gradient echo sequences. 相似文献
3.
Dissolution dynamic nuclear polarization (D-DNP) probes are usually designed for one or at most two specific nuclei. Investigation of multiple nuclei usually requires manufacturing a number of costly probes. In addition, changing the probe is a time-consuming process since a system that works at low temperature (usually between 1.2 and 4.2 K) must be warmed up, thus increasing the risks of contamination. Here, an efficient apparatus is described for D-DNP designed not only for microwave-enhanced direct observation of a wide range of nuclei S such as 1H, 13C, 2H, 23Na, and 17O, but also for cross-polarization (CP) from I=1H to such S nuclei. Unlike most conventional designs, the tuning and matching circuits are partly immersed in superfluid helium at temperatures down to 1.2 K. Intense radio-frequency (RF) fields with amplitudes on the order of 50 kHz or better can be applied simultaneously to both nuclei I and S using RF amplifiers with powers on the order of 90 and 80 W, respectively, without significant losses of liquid helium. The system can operate at temperatures over a wide range between 1.2 and 300 K. 相似文献
4.
Strezov V. Moghtaderi B. Lucas J. A. 《Journal of Thermal Analysis and Calorimetry》2003,72(3):1041-1048
Fears of climate change and increasing concern over the global warming have prompted a search for new, cleaner methods for
electricity power generation. Technologies based on utilising biomass are attracting much attention because biomass is considered
to be CO2 neutral. Co-firing of biomass fuels with coal, for example, is presently being considered as a mean for reducing the global
CO2 emissions. Biomass is also applied in thermal conversion processes to produce fuels with higher calorific values and adsorbents.
In any case, thermal decomposition is essential stage where volatiles and tars are evolved followed by consequent heats of
reactions. In this work sawdust biomass samples were selected in order to study their thermal conversion behaviour. Heats
of decomposition for each sample were measured during continuous heating at a prescribed heating rate under inert atmospheric
conditions. The decomposition generally commenced in all samples at 150°C and was completed at 460°C in a series of endo and
exothermic reactions influenced by its lignin and cellulosic content. Single biomass sample was subjected to heating rates
ranging from 10 to 1000°C min-1 and the effect of heating rate on decomposition was studied. The origin of reactions for each thermal sequence is herein
discussed in detail.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
5.
Tom M. Evans Elham Doroodchi Behdad Moghtaderi 《Journal of nanoparticle research》2011,13(9):4395-4396
This brief communication provides a response to Murshed et al. (J Nanopart Res 12:2007–2010, 2010). We acknowledge that three of the equations in our original article (Doroodchi et al. J Nanopart Res 11:1501–1507, 2009) contained minor typographical errors. However, we confirm that these misprinted equations have no bearing on the results
presented within that article. In addition, we would like to clarify that we do not challenge the methodology of Leong et
al. (J Nanopart Res 8:245–254, 2006). Instead, we repeated their analysis using a more general form for the temperature field with continuity imposed across
the particle–nanolayer–liquid interfaces and found that the solution reduces to the Renovated-Maxwell model. 相似文献
6.
Formation of benzofuran and chlorobenzofuran from 1,3‐dichloropropene: A quantum chemical investigation 下载免费PDF全文
Nwakamma Ahubelem Kalpit Shah Behdad Moghtaderi Alister J. Page 《International journal of quantum chemistry》2015,115(24):1739-1745
We present a quantum chemical investigation of benzofuran and cholorobenzofuran formation mechanisms during the combustion of 1,3‐dichloropropene. Density functional theory and Gaussian‐n thermochemical methods are used to propose detailed mechanistic reaction pathways. These calculations indicate that oxidation of phenylvinyl radical intermediates and subsequent ring closure are key mechanistic pathways in the formation of benzofuran and chlorobenzofuran. Thermochemical and kinetic parameters presented herein will assist in further elucidation of dioxin formation mechanisms from thermolyses of hydrocarbon moieties. © 2015 Wiley Periodicals, Inc. 相似文献
7.
8.
A.S. Dmitrichev V.I. Nekorkin R. Behdad S. Binczak J.-M. Bilbault 《The European physical journal. Special topics》2013,222(10):2633-2646
Space-time dynamics of the network system modeling collective behavior of electrically coupled nonlinear cells is investigated. The dynamics of a local cell is described by the dimensionless Morris–Lecar system. It is shown that such a system yields a special class of traveling localized collective activity so called “anti-phase wave patterns”. The mechanisms of formation of the patterns are discussed and the region of their existence is obtained by using the weakly coupled oscillators theory. 相似文献
9.
Wilfried A. Knig Christiane Fricke Yücel Saritas Behdad Momeni Gerhard Hohenfeld 《Journal of separation science》1997,20(2):55-61
The potential of enantioselective capillary gas chromatography with modified cyclodextrins as chiral stationary phases for authenticity control is demonstrated for a selection of economically important essential oils. Adulteration can be easily detected in cases where enantiomerically pure constituents are present in natural oils. In cases of (naturally) varying enantiomeric compositions of chiral constituents, enantioselective gas chromatography may prove insufficient. 相似文献
10.
Behdad Moghtaderi Iman Shames L. Djenidi 《International Journal of Heat and Fluid Flow》2006,27(6):1069-1077
As part of a larger project aiming at development of a miniaturized hydrogen generator for small mobile/onboard fuel cell applications, a series of experiments was conducted on a novel micro-reactor to examine the effectiveness of its design in promoting the mixing of reactant agents. The reactor is essentially a tubular vessel fitted with a multi-holed baffle plate mounted on a central tube. The mixing phenomenon within the micro-reactor was studied using the micro-PIV (micro-particle image velocimetry) flow visualization technique. Experiments were conducted on a 1:1 scale replica of the reactor. Results indicate that the application of the multi-holed baffle plate considerably improves the mixing performance of the reactor when compared with a simpler co-axial jet tubular reactor. However, the geometrical characteristics of the baffle plate and central tube are found to have dramatic impacts upon the flow structure and mixing patterns within the reactor. Hence, the optimization of the reactor geometry is required to achieve the desirable mixing performance. For the range of Reynolds numbers studied here, the optimum reactor geometry is achieved when the central tube and baffle holes are of similar diameters and baffle holes are located half way between the stream-wise axis and the reactor wall. 相似文献