This thesis focuses on analyzing Cross Laminated Timber manufacture and use for the purpose of suggesting ways to enrich involved technology through the further application of digital fabrication techniques. Framed within the context of making and craft, product and processes are explored to search for opportunities where reevaluating current production methods may arise. It is also in this context that concepts of embodied/ embedded information and emergence are employed to suggest ideas for rethinking CLT, its fabrication and use. Based on research findings, new CLT panel types are prototyped and their required fabrication approaches proposed. The results are applied to a building design for a site in St. John’s, Newfoundland and Labrador.

Materials are a significant aspect of architectural design, the construction components are selected for their availability, location, cultural meaning, physical characteristics and properties. The construction components are defined by their processes of fabrication and making. This thesis investigates processes of making utilizing local materials. It focuses on the relationship between raw material, fabrication, building application and spatial experiences. The proposed site is the former brickyard located outside Bridgetown, Nova Scotia, Canada. Material excavation, fabrication, and construction will all take place on-site. Through material studies, site strategies, and phased program development, it is hoped that an architectural language has been generated that successfully represents the potentials of developing underutilized locally sources material.

The introduction of artificial illumination has brought extensive benefits to mankind, and during the last years we have seen a tremendous progress in this field with the introduction of the energy-efficient light-emitting diode (LED) and the high-contrast organic LED display. These high-end technologies are, however, produced using costly and complex processes, and it is anticipated that the next big thing in the field will be the advent of a low-cost and “green” illumination technology, which can be fabricated in a cost- and material-efficient manner using non-toxic and abundant raw materials, and which features attractive form factors such as flexibility, robustness and light-weight. The light-emitting electrochemical cell (LEC) is a newly invented illumination technology, and in this thesis we present results that imply that it can turn the above vision into reality. The thin-film LEC comprises an active material sandwiched between a cathode and an anode as its key constituent parts. With the aid of a handheld air-brush, we show that functional large-area LECs can be fabricated by simply spraying three layers of solution -- forming the anode, active material, and cathode -- on top of a substrate. We also demonstrate that such “spray-sintered” LECs can feature multicolored emission patterns, and be fabricated directly on complex-shaped surfaces, with one notable example being the realization of a light-emission fork! Almost all LECs up-to-date have been fabricated on glass substrates, but for a flexible and light-weight emissive device, it is obviously relevant to identify more appropriate substrate materials. For this end, we show that it is possible to spray-coat the entire LEC directly on conventional copy paper, and that such paper-LECs feature uniform light-emission even under heavy bending and flexing. We have further looked into the fundamental aspects of the LEC operation and demonstrated that the in-situ doping formation, which is a characteristic and heralded feature of LECs, can bring problems in the form of doping-induced self-absorption. By quantitatively analyzing this phenomenon, we provided straightforward guidelines on how future efficiency-optimized LEC devices should be designed. The in-situ doping formation process brings the important advantage that LECs can be fabricated from solely air-stabile materials, but during light emission the device needs to be protected from the ambient air. We have therefore developed a functional glass/epoxy encapsulation procedure for the attainment of LEC devices that feature a record-long ambient-air operational lifetime of 5600 h. For the light-emission device of the future, it is however critical that the encapsulation is flexible, and in our last study, we show that the use of multi-layer barrier can result in high-performance flexible LECs.

Hybrid plasmonic-photonic structures were introduced as novel platforms for on-chip biochemical sensing and spectroscopy. By appropriate coupling of photonic and plasmonic modes, a hybrid architecture was realized that can benefit from the advantages of integrated photonics such as the low propagation loss, ultra-high Q modes, and robustness, as well as the advantages of nanoplasmonics such as extreme light localization, large sensitivities, and ultra-high field enhancements to bring about unique performance advantages for efficient on-chip sensing. These structures are highly sensitive and can effectively interact with the target biological and chemical molecules. It was shown that interrogation of single plasmonic nanoparticles is possible using a hybrid waveguide and microresonator-based structure, in which light is efficiently coupled from photonic structures to the integrated plasmonic structures. The design, implementation, and experimental demonstration of hybrid plasmonic-photonic structures for lab-on-chip biochemical sensing applications were discussed. The design goal was to achieve novel, robust, highly efficient, and high-throughput devices for on-chip sensing. The sensing scenarios of interest were label-free refractive index sensing and SERS. Nanofabrication processes were developed to realize the hybrid plasmonic-photonic structures. Silicon nitride was used as the material platform to realize the integrated photonic structure, and gold was used to realize plasmonic nanostructures. Special optical characterization setups were designed and implemented to test the performance of these nanoplasmonic and nanophotonic structures. The integration of the hybrid plasmonic-photonic structures with microfluidics was also optimized and demonstrated. The hybrid plasmonic-photonic-fluidic structures were used to detect different analytes at different concentrations. A complete course of research from design, fabrication, and characterization to demonstration of sensing applications was conducted to realize nanoplasmonic and integrated photonic structures. The novel structures developed in this research can open up new potentials for biochemical sensors with advanced on-chip functionalities and enhanced performances.

A new class of electrodes with nanometer-scale contact spacing can be produced at the edge of patterned metal/insulator/metal this film structures. A key challenge is to produce insulator layers with low leakage current and have pristine metal contacts for controlled molecular contacts. Atomic layer deposition of high quality Al2O3 thin films onto Au electrodes was enabled by surface modification with a self-assembled monolayer of -OH groups that react with a monolayer of trimethylaluminum gas source. Ar ion milling was then used to expose the edge of the Au/dielectric/Au structure for molecular electrode contacts. The junctions are characterized by atomic force microscope and tunnel current properties. The Au/self-assembled monolayer/Al2O3/Au tunnel junction, with a very thin oxide insulator layer (15.4 Å), is stable and has a small tunneling current density of about 0.20 ~ 0.75 A/cm2 at 0.5 V. Organometalic cluster molecules were attached to bridge the electrodes. Through tunnel current modeling, low temperature and photo current measurements, molecular current was found to be consistent with direct tunneling through the organic tethers to available states at the metal center. This novel electrode was also used to study the efficiency of organic conducting thin films where the photovoltaic efficiency can be improved when the electrode separation distance is below the exciton diffusion length. Copper (II) phthalocyanine (CuPc) was thermally evaporated between the nano-gap electrodes formed by Au/Al2O3/Au tunnel junctions. A large photocurrent enhancement over 50 times that of bulk CuPc film was observed when the electrode gap distance approached 10 nm. CuPc diffusion length is seen to be 10 nm consistent with literature reports. All devices show diode I-V properties due to a large Schottky barrier contact resistance between the small top Au electrode and the CuPc film. To add another dimension of nm-scale patterning, nanowires can be used as line-of-sight shadowmasks provided that nanowire location and diameter can be controlled. Lateral ZnO nanowires were selectively grown from the edge of a Si/Al2O3/Si multi-layer structure for potential integration into devices utilizing Si processing technology. Microstructural studies demonstrate a 2-step growth process in which the tip region, with a diameter ~ 10 nm, rapidly grew from the Al2O3 surface. Later a base growth with a diameter ~ 22 nm overgrew the existing narrow ZnO nanowire halting further tip growth. Kinetics studies showed surface diffusion on the alumina seed surface determined ZnO nanowire growth rate.

Interest in controlling the synthesis of silver nanoparticles in colloidal solutions has increased during the last two decades. There is also growing interest in forming layers of silver nanoparticles on substrates, particularly for surface-enhanced Raman spectroscopy applications. However, methods to grow silver nanoparticles directly on substrates have not been studied extensively, and there are few techniques for controlling the size, shape, density, and location of the particles. This work presents a simple and reliable method to photodeposit silver nanoparticles onto transparent substrates. The size, shape and deposition density of the nanoparticles are influenced by the precursor solution, light intensity, and surface modification of the substrate. This allows control of the optical and electrical properties of the nanoparticle films. Furthermore, the particles can be patterned using direct laser exposure, scanning probe methods, and electron-beam lithography. Applications and advantages of this deposition method are proposed and explored.

Membrane process including microfiltration (MF), ultrafiltration (UF), nanofiltration (NF) and reverse osmosis (RO) have provided numerous successful applications ranging from drinking water purification, wastewater treatment, to material recovery. The addition of functional moiety in the membranes pores allows such membranes to be used in challenging areas including tunable separations, toxic metal capture, and catalysis. In this work, polyvinylidene fluoride (PVDF) MF membrane was functionalized with temperature responsive (poly(N-isopropylacrylamide), PNIPAAm) and pH responsive (polyacrylic acid, PAA) polymers. It’s revealed that the permeation of various molecules (water, salt and dextran) through the membrane can be thermally or pH controlled. The introduction of PAA as a polyelectrolyte offers an excellent platform for the immobilization of metal nanoparticles (NPs) applied for degradation of toxic chlorinated organics with significantly increased longevity and stability. The advantage of using temperature and pH responsive polymers/hydrogels also includes the high reactivity and effectiveness in dechlorination. Further advancement on the PVDF functionalization involved the alkaline treatment to create partially defluorinated membrane (Def-PVDF) with conjugated double bounds allowing for the covalent attachment of different polymers. The PAA-Def-PVDF membrane shows pH responsive behavior on both the hydraulic permeability and solute retention. The sponge-like PVDF (SPVDF) membranes by phase inversion were developed through casting PVDF solution on polyester backing. The SPVDF membrane was demonstrated to have 4 times more surface area than commercial PVDF MF membrane, allowing for enhanced nanoparticles loading for chloro-organics degradation. The advanced functionalization method and process were also validated to be able to be scaled-up through the evaluation of full-scale functionalized membrane provided by Ultura Inc. California, USA. Nanofiltration (NF) between UF and RO presents selectivity controlled by both steric and electrostatic repulsions, which are widely used to reject charged species, particularly multivalent ions. In this work, selective permeation of CaCl2 and high sucrose retention are obtained through the modification of nanofiltration membranes with lower charge compared to commercial nanofiltration membrane. The membrane module also shows high stability with constant water permeability in a long-term (two months) test. Extended Nernst-Planck equation were further used to evaluate the experimental results and it fits well.

Microfluidic devices have found applications in a number of areas, such as medical analysis, chemical synthesis, biological study, and drug delivery. Because of the small channel dimensions used in these systems, most microchannels exhibit laminar flow due to their low Reynold’s number, making mixing of fluids very challenging. Mixing at this size scale is diffusion-limited, so inducing chaotic flow patterns can increase the interface surface area between two fluids, thereby decreasing overall mixing time. One method to create a chaotic flow within the channel is through the introduction of internal protrusions into the channel. In such an application protrusions that create a rotational flow within the channel are preferred due to their effectiveness in folding the two fluids over one another. The novel mixer outlined in this paper uses a Ti-Ni shape memory alloy for the creation of protrusions that can be turned controlled through material temperature. Controllability of the alloy allows users to turn the chaotic flow created by the protrusions off and on by varying the temperature of the mixer. This ability contributes to the idea of a continuous microfluidic system that can be turned on only when necessary as well as recycle unmixed fluids while turned off.

This thesis is based on promising computing paradigm of reversible logic which generates unique outputs out of the inputs and. Reversible logic circuits maintain one-to-one mapping inside of the inputs and the outputs. Compared to the traditional irreversible computation, reversible logic circuit has the advantage that it successfully avoids the information loss during computations. Also, reversible logic is useful to design ultra-low-power nanocomputing circuits, circuits for quantum computing, and the nanocircuits that are testable in nature. Reversible computing circuits require the ancilla inputs and the garbage outputs. Ancilla input is the constant input in reversible circuits. Garbage output is the output for maintaining the reversibility of the reversible logic but is not any of the primary inputs nor a useful bit. An efficient reversible circuit will have the minimal number of garbage and ancilla bits. Barrel shifter is one of main computing systems having applications in high speed digital signal processing, oating-point arithmetic, FPGA, and Center Processing Unit (CPU). It can operate the function of shifting or rotation for multiple bits in only one clock cycle. The goal of this thesis is to design barrel shifters based on the reversible computing that are optimized in terms of the number of ancilla and garbage bits. In order to achieve this goal, a new Super Conservative Reversible Logic Gate (SCRL gate) has been used. The SCRL gate has 1 control input depending on the value of which it can swap any two n-1 data inputs. We proved that the SCRL gate is superior to the existing conservative reversible Fredkin gate. This thesis develops 5 design methodologies for reversible barrel shifters using SCRL gates that are primarily optimized with the criteria of the number of ancilla and garbage bits. The five proposed methodologies consist of reversible right rotator, reversible logical right shifter, reversible arithmetic right shifter, reversible universal right shifter and reversible universal bidirectional shifter. The proposed reversible barrel shifter design is compared with the existing works in literature and have shown improvement ranging from 8.5% to 92% by the number of garbage and ancilla bits. The SCRL gate and design methodologies of reversible barrel shifter are mapped in Quantum Dot Cellular Automata (QCA) computing. It is illustrated that the SCRL-based designs of reversible barrel shifters have less QCA cost (cost in terms of number of inverters and majority voters) compared to the Fredkin gate- based designs of reversible barrel shifters.

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