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Abstract This research aims at developing a new approach able to simulate 3-D heat and moisture transfer coupled with the mechanical behaviour of a wood during drying process. From the moisture content and temperature profiles, a 3-D formulation and a relevant constitutive model are used to calculate the stress/strain evolution within the board due to shrinkage and external mechanical loading. This allows a fast, comprehensive and realistic model to be implemented. The mechanical model takes into account the hydrous, thermal, mechano-sorptive and elastic deformations, as well as the changes of wood properties, caused by these processes, e.g. porosity, permeability, stress–strain relation, etc. The mathematical model describing simultaneous unsteady heat and moisture transfer between a gas phase and a solid phase during heat treatment has been developed. The conservation equations for the wood sample are obtained using diffusion equation and the 3-D incompressible Navier–Stokes equations have been solved for the flow field. The constitutive equations are discussed in some detail. ANSYS-CFX10 commercial code was used to solve the hygro-thermal problem and FESh++ for the mechanical behaviour. Experimental results obtained regarding temperature, moisture content and deformation profiles during industrial drying of black spruce wood are compared with the numerical results. Satisfactory agreement is obtained over a range of drying air temperatures.

Abstract Films of ruthenium oxide (RuO 2 ) exhibit large, almost constant capacitance, over a potential range of ~ 1.4 V in aqueous acid solutions. This behaviour has led to their development as supercapacitor materials giving many Farads per gram. Applications of electrochemical capacitors require minimum self-discharge rates. In the present paper, the self-discharge kinetics of charged RuO 2 electrodes are studied and a remarkable phenomenon of successive potential recovery after sequential discharge transients is reported. The self-discharge and potential-recovery behaviour is analysed in terms of a process of diffusion of oxidation state involving proton and electron hopping, treated in a model of the RuO 2 film structure having three regions between which redistribution of oxidation states in the oxide film takes place on self-discharge and recovery.

Selenium-dependent glutathione peroxidase activity was assessed in the liver, kidney, lung and blood of mice from seven strains (129/ReJ, BALB/c, C3H/HeSnJ, C3H/S, C57BL/6J, Csb, and S.W.) at five ages (newborn, 21, 70, 175 and +500 days old). Activity was highest in the liver (0.25 U/mg protein) followed by blood hemolysate (0.16 U/mg protein) with kidney and lung displaying similar, comparatively lower levels of activity (0.14 and 0.12 U/mg protein respectively). Although activity was shown by statistical analysis to be not significantly different among the strains (p = 0.05), age-associated, strain-specific changes in enzyme activity were noted to be highly significant (p = 0.001). Also, ethanol administered in drinking water resulted in a marked reduction in selenium-dependent glutathione peroxidase activity during both short- (1-2 weeks) and long- (5-6 weeks) term treatment periods. Changes in this enzyme due to aging and after exposure to xenobiotics such as ethanol may have serious ramifications given the importance of this enzyme in the detoxification of reactive oxygen metabolites.

Abstract Conjugate heat transfer of liquid-gas fin and tube heat exchangers is widely used in industry. However, heat transfer characteristics of such system is difficult to predict as the limiting heat rate can be from either side. This paper aims to quantify the conjugate heat transfer performance of fin and tube heat exchangers via mathematical modeling. Three-dimensional conjugate fluid flow and heat transfer model is developed and validated against the state-of-the-art experimental data and existing analytical correlations. Turbulent k-e model has been employed for the fluid flow and heat transfer modeling. Statistical method, i.e. data reduction and multivariate nonlinear regression techniques, is implemented to analyse the results and to quantify the interaction between parameters. Wide range of parametric studies and simulations is further carried out to evaluate the significance of design, geometrical and operating parameters. According to the results of the study, larger fin length factor and fin pitch and the smaller tube diameter are in favor of fin and tube heat exchangers within the Reynolds number range of 3000–12,000. Finally, a novel conjugate heat transfer correlation for liquid-gas finned tube heat exchangers is proposed to assist engineers for practical designs and applications. The results suggest that our new correlation gives rise to a more accurate conjugate heat transfer prediction as compared to that of traditional non-conjugate counterpart.

Summary Separating edaphic impacts on tree distributions from those of climate and geography is notoriously difficult. Aboveground and belowground factors play important roles, and determining their relative contribution to tree success will greatly assist in refining predictive models and forestry strategies in a changing climate. In a common glasshouse, seedlings of interior Douglas‐fir (Pseudotsuga menziesii var. glauca) from multiple populations were grown in multiple forest soils. Fungicide was applied to half of the seedlings to separate soil fungal and nonfungal impacts on seedling performance. Soils of varying geographic and climatic distance from seed origin were compared, using a transfer function approach. Seedling height and biomass were optimized following seed transfer into drier soils, whereas survival was optimized when elevation transfer was minimised. Fungicide application reduced ectomycorrhizal root colonization by c. 50%, with treated seedlings exhibiting greater survival but reduced biomass. Local adaptation of Douglas‐fir populations to soils was mediated by soil fungi to some extent in 56% of soil origin by response variable combinations. Mediation by edaphic factors in general occurred in 81% of combinations. Soil biota, hitherto unaccounted for in climate models, interacts with biogeography to influence plant ranges in a changing climate.

Modal transformation decomposes three-phase power system voltages or currents into three sets of de-coupled quantities. The symmetrical components transformation is a well-known example of modal transformation. In this paper, the applications and performances of three different modal transformations for determining power system harmonic impedances are investigated. The results show that the symmetrical components transformation is not the best candidate for harmonic impedance calculation. The Clarke and 012 transformations can provide more reliable results. Computer simulation and field measurement results are used to demonstrate the pros and cons of different transformation methods.

When rats are presented with a novel saccharin solution and immediately injected with either morphine or ethanol, they subsequently develop a conditioned taste aversion (CTA) to the saccharin solution which reflects the aversive component of the conditioning drug. The present study provides evidence which suggests that both morphine-induced and ethanol-induced CTAs can be blocked by the specific high-affinity binding opiate antagonist, naloxazone.

In this paper, new optimal power flow (OPF) techniques are proposed based on multiobjective methodologies to optimize active and reactive power dispatch while maximizing voltage security in power systems. The use of interior point methods together with goal programming and linearly combined objective functions as the basic optimization techniques are explained in detail. The effects of minimizing operating costs, minimizing reactive power generation, and/or maximizing loading margins are then compared in both a 57-bus system and a 118-bus system, which are based on IEEE test systems and modeled using standard power flow models. The results obtained using the proposed mixed OPFs are compared and analyzed to suggest possible ways of costing voltage security in power systems.

Abstract The importance of integrating resources criticality assessment into Life Cycle Assessment (LCA) under the Life Cycle Sustainability Assessment (LCSA) framework has been discussed for some time. However, the question how to proceed towards integration remain unclear. Only very few work is published on this issue and to our knowledge only Schneider et al. (2014) have developed one operational model. In this paper we review existing literature critically and explain why integration is important and how it could be done, using knowledge from outside the LCA field. The criticality assessment method proposed by Graedel et al. (2012) is identified as the best starting point. This paper shows based on a critical review why bridging towards such a method could help addressing criticality in LCSA, what are possible options and which research needs exists. It reveals that currently LCA does not adequately cover resource criticality and that methods like Graedel et al. (2012) are inspiring further development of LCA; both approaches have a complementary nature and hence could be developed towards integration within the LCSA framework. Currently resource indicators are not meaningful in LCA, wherefore there is no consensus in LCA community on what to recommend; hence the Area of Protection Natural Resources needs to be rethought. Broadening the scope of LCA towards LCSA provides a conceptual framework to keep LCA relevant for assessing sustainability challenges like access to resources.