Additional file 1: of Mathematical modelling of interacting mechanisms for hypoxia mediated cell cycle commitment for mesenchymal stromal cells

Parameter values and initial conditions. (DOCX 23 kb

Additional file 3: of Mathematical modelling of interacting mechanisms for hypoxia mediated cell cycle commitment for mesenchymal stromal cells

Compiled hypoxic MSCs growth data. (DOCX 23 kb

Additional file 2: of Mathematical modelling of interacting mechanisms for hypoxia mediated cell cycle commitment for mesenchymal stromal cells

The effect of initial conditions on steady state E2F concentration. (DOCX 42 kb

Impact of Bioenergy Production on Ecosystem Dynamics and ServicesA Case Study on U.K. Heathlands

For sustainability’s sake, the establishment of bioenergy production can no longer overlook the interactions between ecosystem and technological processes, to ensure the preservation of ecosystem functions that provide energy and other goods and services to the human being. In this paper, a bioenergy production system based on heathland biomass is investigated with the aim to explore how a system dynamics approach can help to analyze the impact of bioenergy production on ecosystem dynamics and services and vice versa. The effect of biomass harvesting on the heathland dynamics, ecosystem services such as biomass production and carbon capture, and its capacity to balance nitrogen inputs from atmospheric deposition and nitrogen recycling were analyzed. Harvesting was found to be beneficial for the maintenance of the heathland ecosystem if the biomass cut fraction is higher than 0.2 but lower than 0.6, but this will depend on the specific conditions of nitrogen deposition and nitrogen recycling. With 95% recycling of nitrogen, biomass production was increased by up to 25% for a cut fraction of 0.4, but at the expense of higher nitrogen accumulation and the system being less capable to withstand high atmospheric nitrogen deposition

Comparative Assessment of Gasification Based Coal Power Plants with Various CO₂ Capture Technologies Producing Electricity and Hydrogen

Seven different types of gasification-based coal conversion processes for producing mainly electricity and in some cases hydrogen (H₂), with and without carbon dioxide (CO₂) capture, were compared on a consistent basis through simulation studies. The flowsheet for each process was developed in a chemical process simulation tool “Aspen Plus”. The pressure swing adsorption (PSA), physical absorption (Selexol), and chemical looping combustion (CLC) technologies were separately analyzed for processes with CO₂ capture. The performances of the above three capture technologies were compared with respect to energetic and exergetic efficiencies, and the level of CO₂ emission. The effect of air separation unit (ASU) and gas turbine (GT) integration on the power output of all the CO₂ capture cases is assessed. Sensitivity analysis was carried out for the CLC process (electricity-only case) to examine the effect of temperature and water-cooling of the air reactor on the overall efficiency of the process. The results show that, when only electricity production in considered, the case using CLC technology has an electrical efficiency 1.3% and 2.3% higher than the PSA and Selexol based cases, respectively. The CLC based process achieves an overall CO₂ capture efficiency of 99.9% in contrast to 89.9% for PSA and 93.5% for Selexol based processes. The overall efficiency of the CLC case for combined electricity and H₂ production is marginally higher (by 0.3%) than Selexol and lower (by 0.6%) than PSA cases. The integration between the ASU and GT units benefits all three technologies in terms of electrical efficiency. Furthermore, our results suggest that it is favorable to operate the air reactor of the CLC process at higher temperatures with excess air supply in order to achieve higher power efficiency

Modeling and upscaling analysis of gas diffusion electrode-based electrochemical carbon dioxide reduction systems

As an emerging technology for CO2 utilization, electrochemical CO2 reduction reaction (ECO2RR) systems incorporating gas diffusion electrodes (GDE) have the potential to transform CO2 to valuable products efficiently and environment-friendly. In this work, a two-dimensional multiphase model capturing the details of the catalyst layer in a GDE that produces formate with byproducts is established and quantitatively validated against experimental data. This model is capable of describing the mixture gas and aqueous species transportation, electron conduction processes, and a series of interrelated chemical and electrochemical reactions. Specific electrical energy consumption (SEEC) and product yield (PY) have been introduced and used to examine the GDE scalability and evaluate the system performance. The results predict the optimal values for applied cathode potential and catalyst loading and porosity. The effect of inlet gas composition and velocity is also evaluated. Moreover, this study predicts that the GDE is scalable as it retains a stable performance as its geometrical surface area varies. This model together with the simulation findings contributes to the improved understanding of GDE-based CO2 conversion as needed for the future development toward successful industrial applications