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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
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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
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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
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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
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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
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Gravity currents are important physical phenomena which have direct implications in a wide range of physical situations including geophysical processes, air conditioning, and building fires where they are responsible for the transport of smoke and hot gases, particularly, along long corridors. Despite recent progress in the field, relatively little is known about the structure of gravity currents under conditions pertinent to building fires. In particular, the impact of heat transfer at boundaries is not well understood. The present investigation is an attempt to address this shortcoming by studying the turbulent structure of gravity currents under both adiabatic and isothermal boundary conditions. For this purpose, a series of experiments was conducted in a rectangular tank with turbulent underflows. Laser Doppler velocimetry was employed to quantify the velocity field and associated turbulence parameters. Experimental results indicated that the mean flow within the head region primarily consisted of an undiluted large single vortex which rapidly mixed with the ambient flow in the wake region. Flows with isothermal wall boundary conditions showed three-dimensional effects whereas those with adiabatic walls exhibited two-dimensional behaviour. Turbulence was found to be highly inhomogeneous and its distribution was governed by the location of large eddies. While all components of turbulence kinetic energy showed minima in the regions where velocity was maximum (i.e. low fluid shear), they reached their maximum in the shear layer at the upper boundary of the flow. 相似文献
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