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The environmental concerns of C02 emissions resulting from the increasing consumption of fossil fuels over the past decades has called for greater utilisation of renewable energy resources such as solar energy, wind power and biomass energy. Currently, biomass combustion is the dominant conversion technology that is used to extract energy from biomass feedstock at all scales. However, biomass combustion can lead to significant amounts of gaseous (e.g. NOx, CO) and particulate matter (PM) emissions, which is a particular concern for simple and small scale biomass combustion stoves and boilers. The present PhD work aims to achieve low emissions of NOx, CO and PM with a 50kW commercial boiler burning different woody and non-woody biomass pellets by the use of combustion modifications and a particulate removal unit. The combustion performance and emissions of NOx, CO and PM of the boiler were experimentally investigated with three different types of woody and non-woody biomass fuels. Different operating conditions for the minimisation of NOx and CO emissions, including the 'air staging' method and the novel 'reverse flame box' system, have been studied. An innovative particulate filter unit was installed in the flue path of the boiler as a means to reduce PM emissions. CFD modelling of the tested boiler has been carried out and the simulation results have been presented and discussed in this thesis. The experimental results showed that the modified biomass boiler could handle woody biomass pellets while maintaining low levels of CO and NOx emissions. It could also handle non-woody biomass pellets if appropriate additives are added. An approximate 40% NOx reduction was achieved when the boiler was incorporated with a novel low emissions strategy termed as a 'reverse flame box', compared to the original boiler design. With the use of the innovative particulate filter unit, the PM emissions were reduced to about 1 mg/m3, which shows the particulate filter unit reduces PM emissions by over 98%. For the CFD simulation, the modelling results showed the correct trends, although it did not predict adequately the degree to which the boiler configurations affect the emissions.

Robotics has markedly extended the reach of human beings in sensing, manipulating, and transforming the world around us. One of the most inspiring challenges in science and technology is to extend our capacity with tiny robots towards operations at the micro/nanoscales, a dimension where we can directly interact with fundamental biological building blocks. This thesis is devoted to advancing micro/nanorobotics to extend human being’s capacities in following three themes, with a special focus being given to biomedical applications. The first theme focuses on design and fabrication of bio-inspired un-tethered nanorobots with efficient locomotion, adaptive operation, collective regulation, and eventually biological function towards operation in whole blood. The second theme explores the versatility of functional micro/nanorobots to perform diverse tasks including writing (nanolithography), reading (superresolution imaging), destroying (warfare agents), and repairing (surface cracks), all at the micro/nanoscale. The third theme employs self-propelling microrobot as an active delivery technique that autonomously and precisely transports the therapeutic agents inside live animal’s gastrointestinal tract, improving therapeutic efficacy for bacterial infection treatment. This technique opens the door for micro/nanorobots as an active delivery platform for medical treatment and is promising for a wide range of personalized diagnostic and therapeutic applications. Ultimately, micro/nanorobots has the potential to change the game of science, engineering, and medicine by extending our capacity at the micro/nanoscale. The novel applications presented in this thesis are just a few examples showing the power of micro/nanorobots, with countless more avenues waiting to be explored towards living and active matter, and eventually artificial intelligence and synthetic life at the micro/nanoscale.