Open Theses & Dissertations

Permanent URI for this collection

https://unbscholar.lib.unb.ca/handle/1882/12778

Browse

Now showing 1 - 20 of 72

A comprehensive CANDU-6 model: Primary side transport of dissolved and particulate radioactive species
(University of New Brunswick, 2017) Palazhchenko, Olga, Yurivna; Lister, Derek
Adsorption of Pb (II) ions from water using magnetically modified biochars obtained from microwave-assisted pyrolysis
(University of New Brunswick, 2020) Godwin, Patrick Muesi; Xiao, Huining; Afzal, Muhammad
In this study, biochars were produced from biomass at pilot scale in a microwave-assisted pyrolysis process. These pyrolyzed biochars were magnetically modified to improve their adsorption performance and facilitate the recovery of the spent biochars from solution. The magnetic chars were investigated as a potential renewable bio-sorbents for removing lead ions from aqueous solution in a batch-mode experiment. The biochar samples from microwave pyrolysis of 1.5 kg hemp stalks and maple wood chips biomass at a temperature range of 500–700 ˚C were first impregnated with H[subscript 2]O[subscript 2] (30%) solution and then magnetized by mixing aqueous Fe[superscript 3+]/Fe[superscript 2+] solution with biochar suspensions, followed by NaOH treatment. The synthesized magnetic adsorbents were characterized. The effects of temperature, pH, dosage, contact time and initial concentration of Pb (II) solution on adsorption were examined. Adsorption kinetics and isotherm of the modified biochars were modelled and their adsorption performance after 5 regeneration cycles quantified. The adsorbents recovery from solution with a low magnetic field was investigated. The prepared magnetic biochars demonstrated a potential as renewable adsorbents in treating lead ions-contaminated water. Keywords: Microwave-pyrolysis; Magnetic biochar; hemp; maple; adsorbent; water treatment; heavy metal ions.
An engineering and economic viability assessment of converting municipal sewage sludge to biocrude via hydrothermal liquefaction (HTL) and catalytic hydrothermal gasification (CHG)
(University of New Brunswick, 2019) Mergl, Andrew; Cook, William
The economic feasibility of a combined hydrothermal liquefaction (HTL) and catalytic hydrothermal gasification (CHG) process using municipal sewage sludge (MSS) as a feedstock was investigated. A predictive economic model was prepared to determine the areas within the process with the largest economic influence of the design. Laboratory experiments were focused on varying the temperature (280-320°C), residence time (10-40 minutes), and feedstock solids content (5-20wt%) of a batch HTL reaction using local MSS samples. Data from the experiments were input into the model to provide Chief Defense Contractors Inc. an engineering assessment of the proposed process. Economic results indicate that with sufficient feedstock/product flow there exists several scenarios with positive net present values. Experimental data suggests that higher operating temperatures and feedstock solids contents are favourable towards the conversion of carbon from MSS to biocrude.
An investigation of iron concentration effects and modelling of flow accelerated corrosion
(University of New Brunswick, 2017) Alexander Briggs, Michael; Lister, Derek
Flow accelerated corrosion (FAC) is an aggressive form of degradation in power plant piping that leads to substantial wall thinning and sudden failures. An interaction of a complex series of mechanisms, FAC is difficult to detect, requiring predictive tools to identify susceptible components and guide the deployment of mitigating measures. An experimental investigation has been carried out examining the e↵ect of changes in iron concentration on the rate of FAC. A sampling system and process were developed to measure bulk iron concentration in concert with measured FAC rates in an experimental probe at temperature. The UNB mechanistic model has been updated to provide an improved response to variations in bulk iron concentration. The model has also been updated to respond more e↵ectively to mass transfer variations in order to model complex geometry and highly turbulent flow.
An OpenMC model for the analysis of a 100 MWe sodium fast reactor with gas expansion modules for additional passive safety
(University of New Brunswick, 2024-08) Hartery, Noah; Cook, William
Sodium fast reactors (SFR) have a rich history in North America and are still prevalent in advanced reactor designs such as the ARC-100, a Canadian design planned for construction at Point Lepreau, New Brunswick. A 100 MWe SFR was modeled in OpenMC to investigate the incorporation of gas expansion modules (GEMs) for additional passive safety and potential for medical isotope production. It was found that 12 GEM assemblies located on the periphery of the core introduce -4.8 ± 0.06 mk of reactivity, equivalent to -75 ± 1 cents. The fuel temperature coefficient of reactivity was found to be -0.022 ± 0.003 mk⋅K -1, while the coolant and structural materials do not noticeably influence reactivity. As expected, decreases in assembly and pin diameters increase reactivity by increasing power density. The passive safety characteristics of sodium fast reactors were affirmed, and GEMs were shown to be an effective mechanism for introducing negative reactivity.
Beeswax emulsions and microcapsules for hydrophobic modification of cellulose fiber networks
(University of New Brunswick, 2012) Xu, Ji Xiao; Xiao, Huining
Various beeswax emulsions and beeswax-based microcapsules were developed in an attempt to reduce the water vapor transmission rate (WVTR) of cellulose fiber networks of paper products which are of great importance for green-based packaging materials. Four different systems were established and investigated: the block polymer (PE-b-PEG) stabilized beeswax emulsion, cationic starch-stabilized beeswax emulsion, nanobentonite-stabilized beeswax emulsion, and starch microcapsules loaded with beeswax. Each emulsion system or latex was applied to paper handsheets via wet-end addition, surface coating or the combination of wet-end addition and coating. The resulting paper products were well characterized with particular attention paid to WVTR measurements. According to the ASTM E-96, a wet-cup method was developed to quantify the WVTR values at the condition of 38°C and 90% relative humidity (RH). The results indicated that the hydrophobic modification of fiber networks increased the hydrophobicity of paper substantially and reduced the WVTR by 70%. The combination of wet-end addition and surface coating creates the synergy in lowering WVTR.
Bio-nanocomposites for enhancing water vapor barrier of cellulose-based packaging materials
(University of New Brunswick, 2016) Farmahini-Farahani, Madjid; Xiao, Huining
The use of renewable materials within the packaging industry has gained increasing interest in recent years. Cellulose fiber is the most abundant biopolymer on planet earth due to it is sustainable, biodegradable and environmental friendly nature, it is widely utilized in many fields. However, the barrier properties of porous and hydrophilic cellulose fiber network products are inadequate for most barrier applications. In order to improve its barrier properties and widen its applications, extensive studies have been carried out in the current thesis work. In the first section, two biopolymers, poly lactic acid (PLA), poly (3-hydroxybutyrate-co-4-hydroxybutyrate), (PHBV) and their nanocomposites with different nanoclays and with various clay contents were coated on paper. Moreover, various coating methods were also used to control the hydrophilic surface and cover the porous structure of paper in an attempt to improve the water vapor resistance of paper products. It was found that the coating method and clay exfoliation were the most important factors affecting water vapor permeability. The papers coated with exfoliated PHBV nanocomposites drastically improved the water vapor barrier of the paper by lowering the water vapor transmission rate (WVTR) to a level that is similar to those of polypropylene (PP) and low density polyethylene (LDPE). In the second section, a simple route was used to produce regenerated cellulose and regenerated cellulose nanocomposites with sodium-montmorillonite (Na-MMT). A series of novel modified montmorillonites were prepared via solution blending in aqueous alkaline/urea solvent at low temperatures, followed by regeneration of films. The effect of nanoclays loading on the mechanical, crystallinity and water vapor transmission properties of the nanocomposites was investigated. Generally, nanoclays loading improved the mechanical and water vapor barrier properties of the cellulose films. Although, the WVTR values of the resulted nanoclay-cellulose films was much lower than regular paper, but the WVTR values remain much higher than most of the fossil-based polymers.
Bioremediation of lubricant oil-contaminated sand using vermicompost tea and biopolymer
(University of New Brunswick, 2024-08) Rakhodaei, Mohammad; Romero de Zerón, Laura; Hassan, Ikrema; Rogers, Kyle
Bioremediation methods have garnered interest as environmental problems continue to rise. In the past decade, vermicomposting has become more important because it is intrinsically environmentally friendly. This study investigated the effectiveness of vermicompost tea and a biopolymer as flushing agents. Waste lubricant oil (WLO), which was the petrochemical hydrocarbon pollutant evaluated, was injected into a sand pack. Five displacement experiments were conducted. Vermicompost tea/biopolymer and tap water/biopolymer (baseline experiment) were injected into the contaminated sand pack following a pre-established injection sequence. The results showed that remediation using vermicompost tea/biopolymer removed 98% of the pollutant, while the baseline experiment removed a maximum of 81% of the contamination. Germination tests supported the positive effects of the sand reclaimed using vermicompost tea/biopolymer as flushing agent. Overall, this study demonstrated the effectiveness of vermicompost tea/biopolymer as a bio-flushing agent for the remediation of sand contaminated with a hydrocarbon derived pollutant.
Catalytic co-conversion of glycerol and proton-donor species to gasoline-range aromatics over alumina
(University of New Brunswick, 2016) Shahnazari, Arian; Zheng, Ying
Glycerol is the main by-product of the biodiesel production process. Saturation of this by-product in the market would negatively affect the growth of biodiesel production industry. Due to complexities in the purification processes of crude-glycerol, less costly chemical conversion of glycerol to value-added products and feedstocks such as propenal and aromatics has gained more attention recently. In this work, the influence of co-feeding proton-donor and olefin-donor species on the catalytic conversion of glycerol over alumina catalyst to gasoline-range aromatics is studied. During the individual catalytic conversion of glycerol over alumina, because of the shortage of proton-donor intermediates in the process and high activity of glycerol on alumina at 470℃, glycerol mostly leads to form high carbon deposit content and aqueous phase stream, but less liquid organic production. Introducing methanol and ethanol as compound models of alcohols, and dodecane and hexadecane as compound models of long-chain alkanes next to glycerol remarkably decreases the formation of undesired stream, while selectivity to aromatics substantially increases. In terms of liquid aromatics generation and restricting the excessive carbonization on the catalyst surface, co-feeding 25 wt.% hexadecane with 75 wt.% glycerol has the highest efficiency among the selected compound models; with increasing the liquid aromatics selectivity from 17.7% to 42.5%. Additionally, Co-processing the latter compound model, noticeably shifts the distribution of produced aromatics from heavy undesired aromatics range to the gasoline-range aromatics such as xylenes and toluene. The potential influence of hexadecane on the glycerol to aromatics reaction pathway over alumina catalyst is also proposed, and the effective reactions between glycerol and hexadecane intermediates are discussed. It is also found that selecting a very high or low operational temperature would inversely affect the optimization of aromatics formation through the co-processing runs of glycerol and hexadecane.
Characterization of a flexible nanocomposite material for tactile sensing
(University of New Brunswick, 2014) Körmendy, Árpád; Chibante, L.P. Felipe
This project investigates a new soft, flexible piezoresistive composite material, fabricated from Sylgard® 184 silicone elastomer and generic carbon nanotubes (CNTs). This explorative project specifically investigates the overall material production procedure and measurement methods in an attempt to understand and characterize the material properties. The material production method will show that employing sonication mixing of CNTs in chloroform solvent overcomes the characteristic clumping behaviour that prevents uniform dispersion of the filler in solution. This study explores the importance of the heat curing process and demonstrates the difficulties in the fabrication process. The bulk resistance of the material is measured using both ASTM standards and by a custom created 20-point uniformity measurement device. A selection of electrode materials are tested and compared to see the effect of surface resistance in attempt to measure the uniformity of the bulk resistance. This study reports the creation of a pressure sensitive composite material following a developed material recipe, demonstrates the effectiveness of CNT dispersion in Sylgard by means of sonication, that the average bulk resistance is best measured using the ASTM standard method and demonstrating that the developed 20-Point test method is a viable means of measuring resistive uniformity under dynamic force loading.
Characterization of oxide films grown by flow-accelerated corrosion using scanning electron microscope (SEM) and focused ion beam (FIB) techniques
(University of New Brunswick, 2020) MacLennan, Cale; Lister, Derek
Flow-Accelerated corrosion (FAC) has remained an issue in steam raising power plants with FAC being the cause of enhanced degradation of plant piping and if the degradation continues it can develop into unexpected pipe wall failure. Therefore understanding the mechanisms of FAC is necessary in order to predict where it will occur and what can be done to mitigate it. To this end a morphology study was conducted on probes corroded by FAC in various conditions. By observing the changes in oxide layer morphology in response to changes in system conditions more information about the mechanisms of FAC can be inferred. The information gained from the morphology study was then used to update the UNB mechanistic model to improve the accuracy of its predictions. After updating the model, it was able to predict FAC rates and oxide thicknesses quite well in both neutral and ammoniated conditions for two different compositions of steel.
Controlled surfactant adsorption and release within oil formations for enhanced oil recovery
(University of New Brunswick, 2014) Alhassawi, Hassan Mahdi; Romero-Zerόn, Laura
The adsorption of surfactants onto solid surfaces is a major issue during chemical enhanced oil recovery (EOR) applications. Surfactant adsorption reduces the performance of the chemical injection slug and makes the process uneconomical. In this research, a new surfactant delivery system SDS:-CD inclusion complex, was evaluated as an approach to decrease surfactant adsorption. The effectiveness of this system on the surfactant adsorptive behavior was determined through static and dynamic adsorption tests. Likewise, the performance of this approach during EOR surfactant flooding was investigated through sandpack displacement tests under simulated oil reservoir conditions. The research outcomes indicate that this new technology is greatly efficient in reducing the adsorption of surfactant onto solid surfaces. Sandpack testing demonstrated that the surfactant is released at the oil saturation zones within the sandpack and higher incremental oil was recovered in comparison with the conventional EOR surfactant flooding. This technology has great potential for EOR applications.
Density functional theory studies of furfural hydrodeoxygenations on various catalysts
(University of New Brunswick, 2019) Dong, He; Zheng, Ying
Furfural conversions via hydrodeoxygenation pathways were thoroughly investigated by using density functional theory (DFT) calculations on the Ru/Co3O4 surface, Re/Pt bimetallic system, and Ni2P (0001) surface, respectively. On the Ru/Co3O4 surface, it was found that an oxygen vacancy was necessary to be generated in the form of water for the subsequent hydrodeoxygenation of furfural. In order to generate 2-methylfuran, the reaction initiated from hydrogenation of furfural into furyl–CH2O alkoxide intermediate, followed by C–O bond cleavage, and finally the hydrogenation of the unsaturated furyl–CH2 species. This reaction pathway was both kinetically and thermodynamically facile. Comparing with the group X metals and ruthenium, the decarbonylation pathway to produce furan and carbon monoxide was inhibited on Ru/Co3O4 surface by the adsorption geometry. In the Re/Pt bimetallic system, it was found that the kinetically favoured product was furfuryl alcohol, while the 2-methylfuran and water were the thermodynamically favoured products. Based on the calculations, the hydrodeoxygenation product 2-methylfuran was achievable via the hydrogenation of furfural into hydroxyalkyl species, followed by C–OH bond cleavage, and successive hydrogenations of the furyl–CH intermediate. However, the production of 2-methylfuran was prohibited as the oxidised Re surface cannot accept further oxygen deposition, because the removal of oxygen in the form of water via hydrogenations was difficult at the experimental condition. Comparing the results from the Re/Pt system with those on a monometallic flat Pt surface, we were able to demonstrate that incorporation of the oxophilic metals to active hydrogenation metals could promote the hydrodeoxygenation route by reducing the barrier of C–O bond cleavage. As the Ni3P2-termination was more stable than the Ni3P1-termination in Ni2P (0001) surface, it was mainly focused in the calculations. The generation of 2-methylfuran was favoured via hydrogenation to hydroxyalkyl species, followed by the cleavage of C-OH bond and successive hydrogenations, which indicated that the furfuryl alcohol was not a necessary intermediate for the 2-methylfuran formation. During the further conversion of 2-methylfuran, the ring-hydrogenation pathway to generate 2-methyltetrahydrofuran was kinetically favoured than the ring-opening pathway to produce 2-pentanone. The formation of difurfuryl ether could not be achieved without the participation of phosphorus. The adsorption geometry of furfural was the main factor which inhibited the decarbonylation reaction to generate furan on Ni3P2-termination. Based on the comparisons of these three systems for the hydrodeoxygenation of furfural, Ru/Co3O4 system was the best choice which led to a high selectivity of the desire product 2-methylfuran while inhibited the by-products formation.
Deradation behavior of compatibilized poly(butylene adipate-co-terephthalate)/thermoplastic starch blends
(University of New Brunswick, 2012) Tian, Shaojuan; Bendrich, Guida; Xiao, Huining
Nowadays, there is increasing research effort to develop bio-polymers for packaging from renewable sources. This development has caused a need to evaluate the properties of these polymers in different aspects. The current thesis work mainly focuses on the characterization of degradation behavior of poly(butylene adipate-co-terephthalate) (PBAT)/thermoplastic starch (TPS)/Talc composites. In the first part of this study, PBAT/TPS/Talc composites with potato starch in 20, 40, 50, and 60 wt% were prepared in a twin-screw extruder using modified PBAT (PBAT-g-GMA) as a compatibilizer. It was found that the mechanical properties of PGTPS composites were improved remarkably after the addition of talc. At a high strain rate, the tensile strength of all the samples increased significantly whereas the elongation at the break decreased. The second part of this study investigated the biodegradation of PGTPS composites in natural and controlled soil environment. For the biodegradation test in natural soil environment, the surface morphology, weight loss and mechanical properties of the composites were observed every month for 3 months. Results showed that the pure PBAT films almost did not lose weight, while the tensile strength and elongation at the break only changed slightly, which indicated that biodegradability of pure PBAT films was very limited. With increasing starch content in the blends, the tensile strength, and elongation at the break of PGTPS composites were reduced along with the increase of weight loss. More holes and cracks appeared on the surface of the PGTPS composites with prolonging the burial time. The biodegradation of PGTPS composites in controlled environment was evaluated by determining the CO2 released from the bioreactors for 72 days. Result showed that the presence of starch in composites promoted the biodegradation in terms of CO2 evolution. In the third part, the photo-degradation from the ultraviolet (UV) exposure was studied. The changes in the structure of the blends were determined using transform infrared spectroscopy (FT-IR). The main chain scission was found to be responsible for the UV degradation. The starch and talc components did not show any influence on the chemical structure of PGTPS composites in the UV degradation test.
Design of a 3-phase AC Plasma Reactor for Solvent-free Fullerene Synthesis
(University of New Brunswick, 2019-04) Sarawagi, Anshuman R.; Chibante, L.P. Felipe
Fullerenes are spherical carbon molecules with unique chemical and physical properties. A particularly distinctive one is that these molecules have a vapor pressure and can directly sublime from a solid phase to vapor. Since their discovery in 1985, hundreds of articles have been published on numerous synthesis methods. However, a process which is environmentally friendly, continuous, scalable and efficient has yet to be achieved. We propose a system for continuous production of solvent-free manufacture of fullerenes using a novel 3-phase thermal plasma reactor. It is scalable, self-stabilizing, low maintenance and efficient. Helium is used as plasma carrier gas with temperatures >5000°C allowing for vaporization of any carbon feedstock. Fullerene yields of up to ~7 wt% at 1 bar absolute were measured, a higher yield than any other known process. Once the fullerenes are produced, they are then separated using a hot gas sublimation at >600°C which allows for solvent-free separation of fullerenes, resulting in an ultrapure product. Economic analysis of a small pilot reactor indicated a net annual profit of 0.75 million CAD at the pilot scale with a capital investment of 2 million CAD. The cost of sublimed fullerene per gram is estimated to be about ~ 7.8 CAD/g which is substantially lower than its current selling price of 24-102 CAD/g. These results validate the efficiency, scalability, economic feasibility and viability of the process. Hence, the route to environmentally friendly production of solvent-free fullerenes on a commercial scale at affordable prices is soon realizable.
Design of a liquid sodium test loop: For sodium-cooled fast reactor materials and chemistry research
(University of New Brunswick, 2023-04) McNally, Nathan James; Cook, William G.; Palazhchenko, Olga Y.
One promising advanced nuclear reactor technology is the sodium-cooled fast reactor, including ARC Clean Technology’s ARC-100 reactor planned for deployment in New Brunswick. In this work, a liquid sodium test loop is designed to provide research capacity focusing on the corrosion of advanced materials, mass transport, chemistry, and model and instrumentation development. The test loop will simulate non-isothermal sodium heat transport loops operating between a cold leg up to 400°C and a hot leg up to 625°C. Liquid sodium will circulate through a main loop with test vessels and test sections including: fuel pin simulators for cladding testing under heat flux and high velocity flow; a sodium-sodium heat exchanger with a removable tube bundle to simulate intermediate temperature conditions; and, test pots for the insertion of material specimens and instrumentation in liquid sodium. The main sodium loop will be supported by a flexible secondary loop for purification and chemistry diagnostics.
Detoxification of C5 rich prehydrolysate from FPInnovations modified TMP-Bio process for lactic acid fermentation
(University of New Brunswick, 2019) Hiew, Kalian; Ni, Yonghao
This work studied a combination of methods for detoxifying prehydrolysate produced by FPInnovations’ modified TMP-Bio process from hard wood chips for fermentation based bio-refining. The optimal conditions for pH adjustment based removal of fermentation inhibiting compounds was investigated as well as the results of further refining overlimed pressate by membrane filtration in order to remove additional inhibitors. Initial pH adjustment to 11 with continual stirring in a 25°C water bath removed between 14-19% of the total phenols detected in the pressate (in vanillin equivalents), while reducing the concentration of xylose by 25-28%. Samples were subsequently passed through membrane filtration at 200Da, removing up to 28% of the acetic acid detected after overliming. Dilute pressate samples treated with this combination of detoxification steps was fermentable by Bacillus coagulans, consuming 97% or greater of the available xylose within 24 hours.
Development of a high temperature lithium-ion sensor and reference electrode for application in nuclear reactor systems
(University of New Brunswick, 2018) Manley, Maggie; Cook, William
Chemistry control and corrosion mitigation are critical aspects for nuclear and fossil power plant operations in order to ensure efficient operation, reduce maintenance costs, and prevent equipment degradation. High temperature electrochemical sensors may be used for chemistry monitoring and corrosion measurements but can be costly to construct and typically suffer from short life spans in the aggressive, high temperature and pressure systems. A novel concept of combining the corrosion products existing on the power plant piping and the chemistry control regime in CANDU power plants is presented. A lithiated-iron-oxide, lithium ferrite (LiFe5O8), was synthesized, characterized and electrochemically tested as a solid-state high-temperature electrode up to 230°C using a platinum-based reversible hydrogen electrode for verification. Lithiated-hematite (LixFe2O3) and magnetite (Fe3O4) were confirmed as reaction products involved in the redox mechanism. Lithium-ion retention in hematite decreased with temperature as the mobility of the ion was increased; the stoichiometric coefficient x varied from 0.9 to 0.3 between 100°C to 230°C, respectively. The activity of the lithium ion in the redox process suggests potential high-temperature lithium-ion sensing capability for this electrode. An average entropy of reaction in this solid-state redox mechanism was found to be 2.92 kJ/mol/K over the 100°C to 230°C temperature range and the Gibbs Free Energy of formation of the various lithium-inserted hematites were determined as a function of temperature and lithium concentration in solution.
Development of a supervisory control for a kraft pulp mill steam and power system using PCA and PLS
(University of New Brunswick, 2016) Wasson, Richard; Ni, Yonghao
Steam and power systems in kraft pulp mills can be complex and difficult to optimize. Supervisory controls can facilitate the optimization if the appropriate weightings and time delays are applied. The focus of this thesis is to: create models of the steam and power systems of a kraft pulp mill, to evaluate the models, and to develop a control system based on those models. A system involving a kraft recovery boiler, two turbo generators, a batch cooking plant and multiple process users is examined. Partial Least Squares (PLS) and Principal Component Analysis (PCA) are used to develop models that are utilized to develop factors that will be employed in the supervisory controls. Mass and energy balances are completed to validate measurements. A thorough understanding of the system, including the delays associated with changes to the variables, is required to ensure that the supervisory controls improve the responses. As a result, these objectives were satisfied resulting in an increase of 2.2 MWh (21%) of hog fueled power produced, no interruption of process steam users, and statistically significant reductions in steam venting.
Development of an inventory tracking and monitoring system for chemicals using conductive paper -based passive radio frequency identification technology
(University of New Brunswick, 2019) Liu, Xuesi; Ni, Yonghao
Laboratory safety has always been a concern for many institutions and companies. New safety protocols are always being implemented in order to ensure the safety of employees working in potentially hazardous chemical environments. A central chemical database through Radio Frequency Identification (RFID) readers of which the antennas are positioned at the entrance and exit of the chemical storage room was built to achieve automatic inventory management, real-time monitoring and enhanced safety functions. The results show that the chemical inventory system can update automatically without any manual input, the system can alert potential risks including expired chemicals and incompatible chemicals. RFID is a wireless method that utilizes radio-frequency electromagnetic fields to transfer information and identify objects. A passive RFID tag consists of substrate, a chip and antenna. Whereas most RFID tags exploit a classical metallic conductor as the antenna, this project aims to develop and characterize a carbon-based one, which is more environmentally friendly. A RFID antenna was prepared using cellulose nanofibrils (CNF), polyvinyl alcohol (PVA) and reduced graphene oxide (rGO) as raw materials. An antenna with high conductivity and mechanical properties was obtained.

Browse

Browsing Open Theses & Dissertations by Subject "Chemical Engineering"

Results Per Page

Sort Options