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Abstract In this paper, we investigate distributed thermal-electrochemical modeling of a Lithium-Ion battery cell to include the effect of temperature distribution across the thickness of the cell as a first step to study the module level temperature distribution at high charging rates. Most recent works have focused on lumped thermal models for a Li-Ion cell which ignore any temperature differential across cell thickness. However, even a small temperature differential across cell thickness at the cell level can contribute to significant temperature differential in the thickness direction of stacked-up Li-Ion cells at the module level. Such temperature differential can potentially impact the battery charging control system, especially at high charging rates. Here, the thermal-electrochemical partial differential and algebraic equations for a Li-ion cell are solved via a spatial finite difference method. Simulation results show that the temperature differentials over the cell thickness at the cell level are not insignificant, particularly at high charging rates.

Experimental research of photocatalytical oxidation (PCO) of aqueous solutions of de‐icing agents (ethylene glycol and ethylene glycol monoethyl ether) and methyl tert‐butyl ether (MTBE) was undertaken. These chemicals are water‐soluble components of jet and motor fuels accidentally disposed to the environment. Titanium dioxide (Degussa P25) under near‐UV irradiation was selected as a photocatalyst. A slightly acidic medium was preferable for the process efficiency for MTBE, whereas a neutral medium was beneficial for de‐icing agents and jet fuel aqueous extracts. TiO2 suspension fractional composition was found to be dependent on pH and the presence of organic admixtures: the minimum size of TiO2 particles at their maximum uniformity was established in an acidic medium, where the efficiency of PCO of de‐icing agents was the poorest. On the other hand, neutral and slightly acidic media, beneficial for PCO efficiency, were favourable for particle agglomeration, which indicates a minimal role for photocatalyst particle size in PCO efficiency. PCO efficiency increased with increasing MTBE and icing inhibitor concentration. The biodegradability of aqueous solutions of oxygenated additives increased as PCO proceeded. The influence of mineral additives—sulphate, calcium, ferric and manganese ions—on the process efficiency was found to be complex. Special attention was paid to energy‐saving PCO with a photocatalyst attached to buoyant glass micro‐spheres and reduced intensity of stirring of the slurry.

The Arrhenius temperature integral is typically used in non-isothermal kinetic analysis, which is widely applied in gas–solid reactions in separation processes. In previous studies, researchers provided various methods to solve the temperature integral, but the error usually became significant when the value of x (x = Ea/RT) was too large or too small. In this paper, we present a new series method and design a computer program to calculate the temperature integral. According to the precise calculation of the temperature integral, we first reveal the relationship among the integral, the temperature, and the activation energy, and we find an interesting phenomenon in which the 3-D image of the temperature integral is of self-similarity according to fractal theory. The work is useful for mechanism and theoretical studies of non-isothermal kinetics.

A model for pressurised steam/O2-blown fluidised-bed gasification of biomass with catalytic reforming of hydrocarbons and tars was developed using Aspen Plus simulation software. Seven main blocks were used to model the fluidised-bed gasifier and two for the catalytic reformer. Modelling blocks were complemented with FORTRAN subroutines to simulate the observed non-equilibrium behaviour of the process. The model was fitted with experimental data derived from a 0.5 MW scale test rig operated with crushed wood pellets and forest residues and was shown to be capable of predicting product gas composition from gasification of clean wood. A parametric analysis indicated that a significant improvement in the syngas efficiency could be achieved by rising the filtration temperature and reformer conversions. Other improvement possibilities include fuel drying and lower reforming temperature.

In recent years, sustainability concerns have gained increasing attention among countries and stakeholders worldwide. Towards the transition to sustainable rural development, the rural web framework (RWF) has become a consistent tool. Indicators from the RWF have been used to explore sustainable rural development for decision-making tasks, which improves the social, economic, and environmental performance of rural regions. However, the application of the RWF in studies is on the decline. Furthermore, there is a lack of literature reviews on the importance of the RWF and its relationship with different facets of sustainable development. We conducted a systematic literature review (SLR) (a) to explore how studies have used the RWF in the context of sustainable development and (b) to identify areas for further research. This study found that the RWF has mostly been used in developed countries, with fewer applications in developing countries. We suggest that there should be increased application of the RWF, particularly in developing countries, to broaden the rural web–sustainable development discourse and its relevance. This paper presents several areas where the indicators of the RWF can be applied to illustrate their relevance for policy decisions towards the achievement of the sustainable development goals (SDGs).

A Wireless Sensor Network (WSN) is comprised of a number of sensor nodes (SNs) that are randomly placed in an open, harsh environment for many applications. Due to the resource-constrained nature of SNs and hostile deployment environments, energy efficiency and security are considered two key factors in designing WSN routing protocols. This paper proposes an Energy Efficient Secure Multipath (EESM) routing protocol to securely construct efficient routes and transmit data packets between SNs and the base station (BS). EESM achieves energy efficiency through minimal task allocation among SNs whereas all computation-intensive tasks such as network information collection, routing table generation, and network maintenance are performed by the BS. The proposed protocol incorporates lightweight security mechanisms including a one-way hash chain, message authentication code, encryption, and clique-based coordinator selection and monitoring schemes to defend against numerous security attacks. Simulation results show that EESM can successfully detect and protect the network against various security attacks such as replay attacks, sybil attacks, sinkhole attacks, spoofing attacks, compromised node attacks, and so on. In terms of energy efficiency, the proposed protocol achieves an up to 37% increase in network lifetime and a 6% increase in throughput over Secure and Energy Efficient Multipath (SEEM) routing, Secure and Reliable Multipath Routing (SRMR), and Reliable and Multipath Encounter Routing (RMER) protocols. The paper implements the protocol in a real environment using Arduino motes to analyze security overheads and network setup time.

Abstract This paper presents a numerical study of the particle cluster behavior in a riser/downer reactor by means of combined computational fluid dynamics (CFD) and discrete element method (DEM), in which the motion of discrete particles is obtained by solving Newton's equations of motion and the flow of continuum gas by the Navier–Stokes equations. It is shown that the existence of particle clusters, unique to the solid flow behavior in such a reactor, can be predicted from this first principle approach. The results demonstrate that there are two types of clusters in a riser and downer: one is in the near wall region where the velocities of particles are low; the other is in the center region where the velocities of particles are high. While the extent of particle aggregation appears to be similar, the duration time for the first type in a downer is shorter than in a riser. Furthermore, it is demonstrated that the formation of clusters is affected by a range of variables related to operational conditions, particle properties, and bed properties and geometry. The increase of solid volume fraction, sliding and rolling friction between particles or between particles and wall, or damping coefficient can enhance the formation of clusters. The use of multi-sized particles can also promote the formation of clusters. But the increase of gas velocity or use of a wider bed can suppress the formation of clusters. The van der Waals force may enhance the formation of clusters when solid concentration is high but suppress the formation of clusters near the wall region when solid concentration is low.