Combined calcium looping and chemical looping combustion for post‐combustion carbon dioxide capture: process simulation and sensitivity analysis

In this work, a combined calcium looping and chemical looping combustion (CaL--CLC) technology is simulated at thermodynamic equilibrium conditions and the results in terms of efficiency, power production, and solids circulation rates are compared with the case of using CaL alone. In addition, a new solids looping configuration in the CaL--CLC process is proposed with the purpose of mitigating the loss of calcium oxide conversion after high cycle numbers. Simulations show an improved process efficiency of the CaL--CLC method compared with CaL alone (34.2 vs. 31.2 % higher heat value) and an increased power output (136 vs. 110 MWe additional power) due to the higher energy requirement to preheat the reactants. A sensitivity analysis of the process operating parameters highlights the particular importance of the temperature difference between reactors, which has a strong impact on the required mass of solids circulating in the loops. Finally, partial carbon dioxide capture scenarios are considered and indicate that lower capture levels are suitable to match regulation targets

Simulation of a calcium looping CO2 capture process for pressurized fluidized bed combustion

The Canadian regulations on carbon dioxide emissions from power plants aim to lower the emissions from coal‐fired units down to those of natural gas combined cycle (NGCC) units. Since coal is significantly more carbon intensive than natural gas, coal‐fired plants must operate at higher net efficiencies and implement carbon capture to meet the new regulations. Calcium looping (CaL) is a promising post‐combustion carbon capture (PCC) technology that, unlike other capture processes, generates additional power. By capturing carbon dioxide at elevated temperatures, the energy penalty that carbon capture technologies inherently impose on power plant efficiencies is significantly reduced. In this work, the CO2 capture performance of a calcium‐based sorbent is determined via thermogravimetric analysis under relatively high carbonation and low calcination temperatures. The results are used in an aspenONE™ simulation of a CaL process applied to a pressurized fluidized bed combustion (PFBC) system at thermodynamic equilibrium. The combustion of both natural gas and coal are considered for sorbent calcination in the CaL process. A sensitivity analysis on several process parameters, including sorbent feed rate and carbonator operating pressure, is undertaken. The energy penalty associated with the capture process ranges from 6.8 –11.8 percentage points depending on fuel selection and operating conditions. The use of natural gas results in lower energy penalties and solids circulation rates, while operating the carbonator at 202 kPa(a) results in the lowest penalties and drops the solids circulations rates to below 1000 kg/s

Recycling oriented vertical vibratory separation of copper and polypropylene particles

Vibration has been employed in various engineering processes for material handling. The famous Brazil nut effect, large particles tend to rise to the top under vibration, initiates various research about vibration induced particle segregation. Particle size and density are two determining factors for their behaviour under vibration. Previous research in University of Nottingham proves vertical vibratory separation to be a promising environmental friendly mechanical separation method for recycling metallic fraction from shredded Waste Electric and Electronic Equipment (WEEE) stream. A pilot scale thin cell vibratory separator has been developed to investigate the potential for WEEE recycling applications. Shredded copper and polypropylene particles have been chosen to mimic metallic and non-metallic fractions in WEEE. Vibratory separation experiment with controlled environment and addition of solid lubricant are presented in this paper. The result demonstrates the effect of relative humidity and solid lubricant on improving flowability of granular system hence successful vibratory separation. The proposed mechanisms for the presence of moisture and solid lubricant are lubricant effect and elimination of static electricity

An Energy Efficient Coverage Method for Clustered Wireless Sensor Networks

An important issue in WSN is the regional covering A coverage algorithm should be able to solve this issue by considering the power consumption to improve the network lifetime This requires employing the lowest number of sensors A solution is just to turn on a subset of nodes This subset should be chosen in such a way to cover the entire region This can be achieved by partitioning the network nodes and considering a representative for each part in a time slice to perform the responsibilities of all the partition members for full coverage This will lead to turn on some of the nodes in a time slice rather than all of them This paper presents a novel algorithm that employs grouping and time scheduling sensor nodes to turn some of them on to cover the entire area In this algorithm the sensing range of the nodes depends on their energy The cluster head denotes the sensing range and also turn on time slice of each node by considering node s remained energy and positio

The beta-amyloid protein of Alzheimer's disease does not bind to the alpha7 nicotinic acetylcholine receptor

Accumulation of the amyloid protein (Aß) in the brain is an important step in the pathogenesis of Alzheimer's disease. However, the mechanism by which Aß exerts its neurotoxic effect is largely unknown. It has been suggested that the peptide can bind to the a7 nicotinic acetylcholine receptor (a7nAChR). In this study, we examined the binding of Aß1-42 to endogenous and recombinantly expressed a7nAChRs. Aß1-42 did neither inhibit the specific binding of a7nAChR ligands to rat brain homogenate or slice preparations, nor did it influence the activity of a7nAChRs expressed in Xenopus oocytes. Similarly, Aß1-42 did not compete for a-bungarotoxin-binding sites on SH-SY5Y cells stably expressing a7nAChRs. The effect of the Aß1-42 on tau phosphorylation was also examined. Although Aß1-42 altered tau phosphorylation in a7nAChR-transfected SH-SY5Y cells, the effect of the peptide was unrelated to a7nAChR expression or activity. Binding studies using surface plasmon resonance indicated that the majority of the Aß bound to membrane lipid, rather than to a protein component. Fluorescence anisotropy experiments indicated that Aß may disrupt membrane lipid structure or fluidity. We conclude that the effects of Aß are unlikely to be mediated by direct binding to the a7nAChR. Instead, we speculate that Aß may exert its effects by altering the packing of lipids within the plasma membrane, which could, in turn, influence the function of a variety of receptors and channels on the cell surface. © 2007 The Author

Tackling Dementia Together via The Australian Dementia Network (ADNeT): A Summary of Initiatives, Progress and Plans

In 2018, the Australian Dementia Network (ADNeT) was established to bring together Australia’s leading dementia researchers, people with living experience and clinicians to transform research and clinical care in the field. To address dementia diagnosis, treatment, and care, ADNeT has established three core initiatives: the Clinical Quality Registry (CQR), Memory Clinics, and Screening for Trials. Collectively, the initiatives have developed an integrated clinical and research community, driving practice excellence in this field, leading to novel innovations in diagnostics, clinical care, professional development, quality and harmonization of healthcare, clinical trials, and translation of research into practice. Australia now has a national Registry for Mild Cognitive Impairment and dementia with 55 participating clinical sites, an extensive map of memory clinic services, national Memory and Cognition Clinic Guidelines and specialized screening for trials sites in five states. This paper provides an overview of ADNeT’s achievements to date and future directions. With the increase in dementia cases expected over coming decades, and with recent advances in plasma biomarkers and amyloid lowering therapies, the nationally coordinated initiatives and partnerships ADNeT has established are critical for increased national prevention efforts, co-ordinated implementation of emerging treatments for Alzheimer’s disease, innovation of early and accurate diagnosis, driving continuous improvements in clinical care and patient outcome and access to post-diagnostic support and clinical trials. For a heterogenous disorder such as dementia, which is now the second leading cause of death in Australia following cardiovascular disease, the case for adequate investment into research and development has grown even more compelling