Dr Madeleine Bussemaker


Lecturer in Chemical Engineering
BSc (Hon), PhD, AMIChemE, PGCE HE

Academic and research departments

Department of Chemical and Process Engineering.

Biography

Research

Research interests

Research projects

Research collaborations

My teaching

Supervision

Postgraduate research supervision

My publications

Publications

Bussemaker Madeleine, Trokanas N, Cecelja Franjo (2017) An Ontological Approach to Chemical Engineering Curriculum Development, Computers and Chemical Engineering 106 pp. 927-941 Elsevier
Continuous reflection and evolution of curricula in chemical engineering is beneficial for adaptation to evolving industries and technologies and for improving student experience. To this end it was necessary to develop a method to enable a holistic reflection on the curriculum and to examine potential areas of improvement and change. The curriculum was modelled using knowledge modelling through the development of an ontology, Chemical Engineering Education Ontology (ChEEdO) in the Protégé 3.5 environment. ChEEdO models topics, taught modules and the learning outcomes of the modules within the domain of chemical engineering. The learning outcomes were related to the topics using verb properties from Bloom?s taxonomy and the context of each learning outcome. The functionality of semantic reasoning via the ontology was demonstrated with a case study. The modelling results showed that the ontology could be successfully utilised for curriculum development, horizontal and vertical integration and to identify appropriate pre-requisite learning.
Bussemaker MJ, Mu X, Zhang D (2013) Ultrasonic pretreatment of wheat straw in oxidative and nonoxidative conditions aided with microwave heating, Industrial and Engineering Chemistry Research 52 (35) pp. 12514-12522 American Chemical Society
Ultrasound was shown to enhance pretreatment of lignocellulose for biofuel and biorefinery applications and can augment oxidative processes, yet few studies have combined ultrasound with an oxidative environment for the pretreatment of lignocellulose. In the present contribution, pretreatment of a wheat straw using a combination of ultrasound with two oxidative pretreatments, peracetic acid and hydrogen peroxide, as well as water and acetic acid was tested. The experimentation was conducted in an ultrasonic-microwave reactor with a comparison to silent pretreatment with microwave heating alone. In addition, thermal heating was compared to microwave heating for the water pretreatment. Ultrasound produced a higher purity solid residue for all chemical pretreatments. However, ultrasound pretreatment reduced the delignification efficacy by up to 50%, attributed to lignin condensation. The chemical treatments were affected by sonolysis reactions and altered the recoverability of the solubilized carbohydrates. © 2013 American Chemical Society.
Pearce MP, Bussemaker MJ, Cooper PD, Lapere KM, Wild DA, McKinley AJ (2012) Formation of methanol from methane and water in an electrical discharge., Phys Chem Chem Phys 14 (10) pp. 3444-3449
Matrix isolation FTIR experiments have shown that methanol is a major product when argon gas doped with water and methane is exposed to an electrical discharge and condensed to a solid matrix at 11 K. Experiments with (2)H, (17)O and (18)O-labeled isotopologues show the mechanism for the methanol production is likely to be insertion of an excited oxygen atom in the (1)D state into a C-H bond of a methane molecule. In light of these experiments, the possibility of oxygen atom insertion into methane should be considered as a possible mechanism for the production of methanol in interstellar ices.
Trokanas N, Bussemaker M, Velliou E, Tokos H, Cecelja F (2015) BiOnto: An Ontology for Biomass and Biorefining Technologies,
Sonochemical activity is dependent on flow patterns within the reactor and either no affect or a decrease in activity was observed at 376, 995, and 1179 kHz from overhead stirring. The interaction of fluid flow with ultrasound was further investigated in this study with circulatory flow. The effect of fluid circulation on radical production was investigated at two circulation speeds, with and without surface stabilisation. The sonochemical activity was determined by the yield of hydrogen peroxide, measured by iodide dosimetry. The sonochemically active region was pictured using sonochemiluminescence imaging and the flow fields were visualised with dyed flow videos. At 376 and 995 kHz, an increase in sonochemical activity was observed with the slower flow rate; however at 1179 kHz, the sonochemical activity was either not affected or decreased. The observed changes in sonochemical activity were attributed to an increase in asymmetry of the bubble collapse brought about by fluid motion. © 2013 Elsevier B.V. All rights reserved.
Undergraduate laboratory classes are being reviewed and in some cases scaled back because they are expensive to run compared to the learning outcomes for students. We believe that practical experience is essential and should remain an important part of undergraduate chemistry courses. However significant adaptations should be made to broaden the skills that students can take from these classes. We proposed to make changes which increased the value of laboratories as a tool for educating new scientists without increasing the workload for staff or students. The assessment tasks were altered to focus on learning outcomes and resources were improved and made available online and in hardcopy for students and teachers. Worksheets were introduced for each laboratory experiment and the number of full laboratory report assessments halved. The provision of worksheets placed an emphasis on the key chemical concepts and aided students in their understanding of scientific writing conventions. Students were provided with an explicit guide to writing laboratory reports and given feedback on their writing technique. The submission system was moved to the online student platform WebCT to increase flexibility and improve the quality and speed of feedback. These changes were met favorably by students, and the subsequent improvement in quality of student work was noted by the assessors. The study highlighted the importance of demonstrators as teaching staff and the need to provide them with adequate training and resources. While we acknowledge that further development is required we believe that by broadening the focus of assessment beyond chemical theory the needs of cross discipline students were met while still providing chemistry majors with a solid laboratory background.
Mitchell J, Prescott M, Lee J, Velliou E, Bussemaker MJ (2016) Ultrasound-Enhanced Treatment of Pancreatic Cancer,
Bussemaker MJ, Day K, Drage G, Cecelja F (2015) A Value Chain Optimisation Model for a Biorefinery with Feedstock and Product Choices, 12TH INTERNATIONAL SYMPOSIUM ON PROCESS SYSTEMS ENGINEERING AND 25TH EUROPEAN SYMPOSIUM ON COMPUTER AIDED PROCESS ENGINEERING, PT C 37 pp. 1883-1888 ELSEVIER SCIENCE BV
Bussemaker MJ, Day K, Drage G, Cecelja Franjo (2014) Value Chain Optimization Model for a Softwood Biorefinery Based in Scotland,
There is a push towards sourcing chemicals and materials from renewable feedstock such as lignocellulosic biomass. Value chain assessment is used to evaluate the feasibility of the use of a certain technology and feedstock to produce various chemical sources in a given location. In this work an optimisation model for the value chain assessment of a lignocellulosic biorefinery was developed using mixed integer linear programing. The model allows for a comparison of two product sources which undergo mechanical and/or chemical pretreatment prior to processing by the biorefinery into three product streams, delivered to the customer. Optimisation identifies the optimal source or sources of feedstock and the locations of intermediate storages, pretreatments, biorefinery(ies) and customers with respect to maximising profit. The model was verified based on a case study detailed in Scotland. The case study evaluates the use of felled softwood and/or to the use of sawmill by-products with the production of hemicellulose, lignin and cellulose. The results and implications of the optimisation of the scenario are discussed with respect to costs of transport, processing and product values.
Bussemaker M, Day K, Drage G, Cecelja F (2015) A Value Chain Optimisation Model for a Biorefinery with Feedstock and Product Choices,
The effect of flow in an ultrasonic reactor is an important consideration for practical applications and for the scale-up of ultrasonic processing. Previous literature on the influence of flow on sonochemical activity has reported conflicting results. Therefore, this work examined the effect of overhead stirring at four different frequencies, 40, 376, 995 and 1179 kHz, in two different reactor configurations. Comparable power settings were utilised to elucidate the underlying mechanisms of interactions between the flow and sonochemical activity. The sonochemical activity was determined by the yield of hydrogen peroxide, measured by iodide dosimetry, and the active region was visualised with sonochemiluminescence imaging. The overhead stirring in the low frequency reactor altered the yield of hydrogen peroxide so it produced the maximum yield out of the four frequencies. The increase in hydrogen peroxide yield was attributed to a reduction in coalescence at 40 kHz. However at the higher frequencies, coalescence was not found to be the main reason behind the observed reductions in sonochemical yield. Rather the prevention of wave propagation and the reduction of the standing wave portion of the field were considered.
Bussemaker MJ, Xu F, Zhang D (2013) Manipulation of ultrasonic effects on lignocellulose by varying the frequency, particle size, loading and stirring., Bioresource Technology 148 pp. 15-23 Elsevier
The parameters, including ultrasonic frequency, still versus stirring, biomass particle size and biomass loading were concurrently investigated for the ultrasonic treatment of wheat straw. Experiments were conducted at three different frequencies; 40, 376, and 995kHz using three different solid to liquid ratios, 1/50, 1/20, and 1/15(g/ml), with and without mechanical stirring. Additional treatments in different particle size ranges, 0-0.5, 0.5-1, and 1-2mm were performed at the solid to liquid ratio of 1/20(g/ml). Fractionation was improved at 40 and 995kHz via different mechanisms. Delignification was favored at the ultrasonic treatment frequency of 40kHz, biomass loading 1/20(g/ml) with stirring and particle size range of 0.5-1mm. However at 995kHz carbohydrate solubilization was favored, especially in the particle size range of
Bussemaker MJ, Cecelja Franjo (2015) Value Chain Optimisation for a Variable Scenario,
Trokanas N, Bussemaker M, Day K, Drage G, Cecelja F (2015) VCAP: A Software Platform for the Assessment of Biorefinery Value Chains,
Trokanas Nikolaos, Bussemaker Madeleine, Velliou Eirini, Tokos H, Cecelja Franjo (2015) BiOnto: An Ontology for Biomass and Biorefining Technologies, Computer Aided Chemical Engineering 37 pp. 959-964 Elsevier
This paper presents design and implementation of the BiOnto ontology in the domain of biorefining. The ontology models both biomass types and composition and biorefining processing technologies. The designed ontology is verified by a case study in the domain of Industrial Symbiosis.
Bussemaker MJ, Zhang D (2013) Effect of ultrasound on lignocellulosic biomass as a pretreatment for biorefinery and biofuel applications, Industrial and Engineering Chemistry Research 52 (10) pp. 3563-3580 American Chemical Society
The conversion of lignocellulosic biomass for biofuels and biorefinery applications is limited due to the cost of pretreatment to separate or access the biomass's three main usable components, cellulose, hemicellulose, and lignin. After pretreatment, each component may be utilized via chemical conversion, hydrolysis, and/or fermentation. In this review we aim first, to identify the current status-quo of knowledge of the parametric effects of ultrasound, second, to evaluate the potential of ultrasound as a pretreatment and fractionation method of lignocellulose, and last, to identify the challenges that this technology faces. Ultrasound produces chemical and physical effects which were both found to augment the pretreatment of lignocellulose via delignification and surface erosion. The magnitudes of these effects are altered when the ultrasonic field is influenced by parameters such as solvent, ultrasonic frequency, and reactor geometry and type. Therefore, the implementation of ultrasound for the pretreatment of lignocellulose must consider the variation of ultrasonic influences to capitalize on the key effects of ultrasound. Currently the literature is dominated by low frequency ultrasonic treatment, coupled with alkaline solutions. High frequency ultrasound, oxidizing solutions, and use of combined alternative augmentation techniques show promise for the reduction of energy consumed and synergistic enhancement of ultrasonic treatment. Furthermore, feedstock characteristics, reactor configuration, kinetics, and the ultrasonic environment should be considered. © 2013 American Chemical Society.
Prescott M, Mitchell J, Totti S, Lee J, Velliou E, Bussemaker M (2017) Sonodynamic therapy combined with novel anti-cancer agents, sanguinarine
and ginger root extract: Synergistic increase in toxicity in the presence of
PANC-1 cells in vitro.,
Ultrasonics Sonochemistry 40 (B) pp. 72-80 Elsevier
The presence of ultrasound-induced cavitation in sonodynamic therapy (SDT) treatments
has previously enhanced the activity and delivery of certain sonosensitisers in biological
systems. The purpose of this work was to investigate the potential for two novel anti-cancer
agents from natural derivatives, sanguinarine and ginger root extract (GRE), as
sonosensitisers in an SDT treatment with in vitro PANC-1 cells. Both anti-cancer compounds
had a dose-dependent cytotoxicity in the presence of PANC-1 cells. A range of six discreet
ultrasound power-frequency configurations were tested and it was found that the cell death
caused directly by ultrasound was likely due to the sonomechanical effects of cavitation.
Combined treatment used dosages of 100 ¼M sanguinarine or 1mM of GRE with 15 s
sonication at 500 kHz and 10 W. The sanguinarine-SDT and GRE-SDT treatments showed a
6% and 17% synergistic increase in observed cell death, respectively. Therefore both
sangunarine and GRE were found to be effective sonosensitisers and warrant further
development for SDT, with a view to maximising the magnitude of synergistic increase in
toxicity.
Wood R, Lee J, Bussemaker M (2017) A parametric review of sonochemistry: control and augmentation of sonochemical activity in aqueous solutions, Ultrasonics Sonochemistry 38 pp. 351-370 Elsevier
In this review the phenomenon of ultrasonic cavitation and associated sonochemistry is presented through system parameters. Primary parameters are defined and considered, namely; pressure amplitude, frequency and reactor design; including transducer type, signal type, vessel-transducer ratio, liquid flow, liquid height, liquid temperature and the presence of a reflective plate. Secondary parameters are similarly characterised and involve the use of gas and liquid additives to influence the chemical and physical environments. Each of the parameters are considered in terms of their effect on bubble characteristics and subsequent impact on sonochemical activity. Evidence suggests that via parametric variation, the reaction products and efficiency may be controlled. This is hypothesised to occur through manipulation of the structural stability of the bubble.
Bussemaker Madeleine, Trokanas Nikolaos, Cecelja Franjo (2016) An Ontological Approach to Chemical Engineering Curriculum Development, 26th European Symposium on Computer Aided Process Engineering 38 (A & B) pp. 2331-2336 Elsevier
Continuous reflection and evolution of curricula in chemical engineering is beneficial for adaptation to evolving industry requirements, novel technologies and enhances student experience by being up to date and inclusive of effective teaching strategies. To this end it was necessary to develop a method to enable a holistic reflection on the curriculum and to examine the effect and potential areas of improvement and change. The curriculum was modelled using semantic knowledge modelling through the development of an Ontology, ChEEdO in the Protégé 3.5 environment. ChEEdo models topics within the domain of chemical engineering, modules taught in chemical engineering courses and the learning outcomes of these modules. The learning outcomes were related to the topics using verb properties from Bloom?s taxonomy and using the context of each learning outcome. The functionality of semantic reasoning via the ontology was demonstrated with a case study based on curriculum development. The output of the modelling results demonstrated that the ontology could be successfully utilised for curriculum development and this is discussed in relation to practicality and future direction.
Trokanas Nikolaos, Bussemaker Madeleine, Cecelja Franjo (2016) Utilising Semantics for Improved Decision Making in Bio-refinery Value Chains, Computer-Aided Chemical Engineering 38 pp. 2097-2102 Elsevier
This paper presents an effort to utilise semantics to improve the decision making process in biorefinery value chains. In more detail, an ontology describing biomass and biorefineries is used to facilitate the identification of the best options for the population of the optimisation problem. In addition to that, the reasoning capabilities of ontologies are used to enhance search of information. The approach has been verified with a case study for biomass available in Scotland.
Bussemaker Madeleine, Day Kenneth, Drage Geoffrey, Cecelja Franjo (2017) Supply chain optimisation for an ultrasound-organosolv lignocellulosic biorefinery: Impact of technology choices, Waste and Biomass Valorization 8 (7) pp. 2247-2261 Springer Verlag
Conversion of lignocellulose to value-added products is normally focussed on fuel production via ethanol or heat. In this work, a techno-economic assessment of a biorefinery with three product streams, cellulose, hemicellulose and lignin is presented. Moreover, the techno-economic assessment is evaluated in the context of the supply chain through optimisation. A mixed integer linear program was developed to allow for flexible scenarios in order to determine effects of technological and pre-processing variations on the supply chain. The techno-economic and optimisation model integration was demonstrated on a case study in Scotland using woody biomass, either as sawnlogs or sawmill chips. It was established that sawmill chips is the preferred option, however sawnlogs became competitive once passive drying to 30% moisture content (wet basis) was considered. The flexibility of the modelling approach allowed for consideration of technology savings in the context of the supply chain, which can impact development choices.
Bussemaker Madeleine, Trokanas Nikolaos, Koo Linsey, Cecelja Franjo (2018) Ontology Modelling for Lignocellulosic Biomass: Composition and Conversion. Comput-Aided Chemical Engineering, 43, pp 1565-70, Computer Aided Chemical Engineering: 28th European Symposium on Computer Aided Process Engineering 43 pp. 1565-1570 Elsevier
This paper presents an expansion of an already developed ontology BiOnto (Trokanas, Bussemaker, Velliou, Tokos, & Cecelja, 2015) and processing technology eSymbiosis ontology (Raafat, Trokanas, Cecelja, & Bimi, 2013) towards valorisation of lignocellulosic biomass. The ontology provides a reference model interpretable by humans and computers by further classifying and characterizing lignocellulosic biomass (LCB) in several ways, such as: lignin, hemicellulose and cellulose content, C5 and C6 composition, elemental composition, and heat value. Similarly, LCB processing technologies are classified and characterised based on the input of LCB components, with related conversion rates of specific components. The combination of these classifications can elucidate additional information to assist in decision making for the ontology user. For example, the theoretical conversion rates of C5 and C6 polymeric sugars to ethanol are 0.5987 and 0.5679, then by employing the inference capabilities of the knowledge model, the user can gain insights into theoretical ethanol yields for various biomass types based on their C5 and C6 polymeric composition. This can also be applied to theoretical and actual yields of technologies modelled within the ontology, providing a useful reference tool for biorefinery development.
Costello Katie, Gutierrez-Merino J, Bussemaker Madeleine, Ramaiolia M, Baka M, Van Impe J, Velliou Eirini (2018) Modelling the microbial dynamics and antimicrobial resistance development of Listeria in viscoelastic food model systems of various structural complexities, International Journal of Food Microbiology 286 pp. 15-30 Elsevier
Minimal processing for microbial decontamination, such as the use of natural antimicrobials, is gaining interest in the food industry as these methods are generally milder than conventional processing, therefore better maintaining the nutritional content and sensory characteristics of food products.

The aim of this study was to quantify the impact of (i) structural composition and complexity, (ii) growth location and morphology, and (iii) the natural antimicrobial nisin, on the microbial dynamics of Listeria innocua.

More specifically, viscoelastic food model systems of various compositions and internal structure were developed and characterised, i.e. monophasic Xanthan gum-based and biphasic Xanthan gum/Whey protein-based viscoelastic systems. The microbial dynamics of L. innocua at 10oC, 30oC and 37oC were monitored and compared for planktonic growth in liquid, or in/on (immersed or surface colony growth) the developed viscoelastic systems, with or without a sublethal concentration of nisin. Microscopy imaging was used to determine the bacterial colony size and spatial organisation in/on the viscoelastic systems.

Selective growth of L. innocua on the protein phase of the developed biphasic system was observed for the first time. Additionally, significant differences were observed in the colony size and distribution in the monophasic Xanthan gum-based systems depending on (i) the type of growth (surface/immersed) and (ii) the Xanthan gum concentration. Furthermore, the system viscosity in monophasic Xanthan gum-based systems had a protective role against the effects of nisin for immersed growth, and a further inhibitory effect for surface growth at a suboptimal temperature (10oC).

These findings give a systematic quantitative insight on the impact of nisin as an environmental challenge on the growth and spatial organisation of L. innocua, in viscoelastic food model systems of various structural compositions/complexities. This study highlights the importance of accounting for system structural composition/complexity when designing minimal food processing methods with natural antimicrobials.

Alfonso-Muniozguren Pello, Lee Judy, Bussemaker Madeleine, Chadeesingh Ralph, Jones Caryn, Oakley David, Saroj Devendra (2018) A combined activated sludge-filtration-ozonation process for abattoir wastewater treatment, Journal of Water Process Engineering 25 pp. 157-163 Elsevier
Current industrial livestock production has one of the highest consumptions of water, producing up to ten times more polluted (biological oxygen demand, BOD) wastewaters compared to domestic sewage. Additionally, livestock production grows yearly leading to an increase in the generation of wastewater that varies considerably in terms of organic content and microbial population. Therefore, suitable wastewater treatment methods are required to ensure the wastewater quality meets EU regulations before discharge. In the present study, a combined lab scale activated sludge-filtration-ozonation system was used to treat a pre-treated abattoir wastewater. A 24-h hydraulic retention time and a 13-day solid retention time were used for the activated sludge process, followed by filtration (4?7 ¼m) and using ozone as tertiary treatment. Average reductions of 93% and 98% were achieved for chemical oxygen demand (COD) and BOD, respectively, obtaining final values of 128 mg/L COD and 12 mg/L BOD. The total suspended solids (TSS) average reduction reached 99% in the same system, reducing the final value down to 3 mg/L. Furthermore, 98% reduction in phosphorus (P) and a complete inactivation of total coliforms (TC) was obtained after 17 min of ozonation. For total viable counts (TVC), a drastic reduction was observed after 30 min of ozonation (6 log inactivation) at an injected ozone dose of 71 mg/L. The reduction percentages reported in this study are higher than those previously reported in the literature. Overall, the combined process was sufficient to meet discharge requirements without further treatment for the measured parameters (COD, BOD, TSS, P, TC and TVC).
Nalesso Silvia, Bussemaker Madeleine J, Sear Richard P, Hodnett Mark, Lee Judy (2018) Development of sodium chloride crystal size during antisolvent crystallization under different sonication modes, Crystal Growth & Design 19 (1) pp. 141-149 American Chemical Society
This paper reports for the first time the development in the size and shape of sodium chloride crystals during the anti-solvent crystallization in ethanol under different sonication modes. Sonication using 98 kHz and calorimetric power of 6 W was applied either continuously for a range of crystallisation times (5 ? 90 s) or intermittently (5 s pulse). Under silent conditions, crystallization time of 90 s generated crystals with an average size of 73.8 ± 6.9 ¼m, compared to 8.7 ± 2.8 ¼m under 90 s of continuous sonication. However, it was observed that within the first 5 s of sonication at the beginning of the crystallization, the average crystal size was already reduced to 7.0 ± 3.3 ¼m. If the system was left to crystallise further to 90 s without ultrasound, the crystal size grew only slightly to 8.2 ± 1.4 ¼m. When 5 s burst of ultrasound was applied during the crystallization process, a bimodal distribution of small (from sonication) and large crystals (from the silent period) was obtained. These results imply that the major influence of sonication is crystal nucleation rather than fragmentation, and equilibrium is reached with 5 s sonication by precipitating most of the crystals in solution.
Gonzalez V., Wood R., Lee J., Taylor S., Bussemaker M. J. (2018) Ultrasound-Enhanced Hair Dye Application for Natural Dyeing Formulations, Ultrasonics Sonochemistry Elsevier
Advances made in recent years have allowed the application of colorants obtained from natural sources into textile dyeing. The use of ultrasound in the dyeing method is reported to increase dye uptake and decrease dyeing times. The aim of this work is to further extend the knowledge of natural hair dyes considering the use of ultrasound in the dyeing method with commercially available herbal dyes and using goat hair as a model for human hair. Optimal ultrasonic parameters were selected by considering the effects of sonication times (5, 10 and 15 min), frequencies (44, 400 and 1000 kHz) and total dyeing times (30, 60 and 120 min) in the morphology of the dyed hair and the colour intensity. Damage to the hair surface was evaluated by scanning electron microscopy (SEM) images, differences in colour of the dyed hair was obtained by ImageJ analysis and quantification of dye uptake was determined by UV-visible spectroscopy. The evidence from this study suggests an increase in goat hair coloration with the use of ultrasonic energy. Optimal dyeing conditions in consideration of colouration efficacy without hair damage were identified as sonication at 400 kHz for 10 min with a total dyeing time of 60 min.
Nalesso S, Bussemaker Madeleine, Sear R, Hodnett M, Lee JY (2017) Sonocrystallisation: A mystery made of crystals and bubbles,
Koo Linsey, Trokanas Nikolaos, Panteli Anna, Kalemi Edlira, Shah Nilay, Bussemaker Madeleine, Cecelja Franjo (2017) Integration of CAPE Models and Data for the Domain of Biorefining: InterCAPEmodel Ontology Design, Computer Aided Chemical Engineering 40 pp. 2341-2346 Elsevier
design of InterCAPEmodel ontology, which contains a comprehensive description to represent the knowledge of models and data in the biorefining domain, is presented. Primarily, the InterCAPEmodel ontology aims at providing implicit knowledge that reflects process synthesis logic, and explicit knowledge including a complete set of input/output types and the parameters associated with each model and dataset to manage the repository. At present, the InterCAPEmodel ontology supports integration of model and/or data. To fully exploit the potential of providing the description of the model and data to sufficiently support semantic integration, the design of knowledge model is described and the use of ontology that demonstrates its functionality is presented using a case study of a lignocellulosic based biorefining models and data at supply chain level.
Bussemaker Madeleine J, Day Kenneth, Drage Geoffrey, Cecelja Franjo (2017) Supply Chain Optimisation for an Ultrasound-Organosolv Lignocellulosic Biorefinery: Impact of Technology Choices, Waste and Biomass Valorization 8 (7) pp. 2247-2261 Springer
Conversion of lignocellulose to value-added products is normally focussed on fuel production via ethanol or heat. In this work, a techno-economic assessment of a biorefinery with three product streams, cellulose, hemicellulose and lignin is presented. Moreover, the techno-economic assessment is evaluated in the context of the supply chain through optimisation. A mixed integer linear program was developed to allow for flexible scenarios in order to determine effects of technological and pre-processing variations on the supply chain. The techno-economic and optimisation model integration was demonstrated on a case study in Scotland using woody biomass, either as sawnlogs or sawmill chips. It was established that sawmill chips is the preferred option, however sawnlogs became competitive once passive drying to 30% moisture content (wet basis) was considered. The flexibility of the modelling approach allowed for consideration of technology savings in the context of the supply chain, which can impact development choices.
Bussemaker Madeleine, Trokanas Nikolaos, Cecelja Franjo (2016) An Ontological Approach to Chemical Engineering Curriculum Development, ESCAPE 26 Elsevier
Continuous reflection and evolution of curricula in chemical engineering is beneficial for adaptation to evolving industry requirements, novel technologies and enhances student experience by being up to date and inclusive of effective teaching strategies. To this end it was necessary to develop a method to enable a holistic reflection on the curriculum and to examine the effect and potential areas of improvement and change. The curriculum was modelled using semantic knowledge modelling through the development of an Ontology, ChEEdO in the Protégé 3.5 environment. ChEEdo models topics within the domain of chemical engineering (Topics), modules taught in chemical engineering courses (Modules) and the learning outcomes of these modules (LearningOutcomes). The learning outcomes were related to the topics using verb properties from Bloom?s taxonomy and using the context of each learning outcome. The functionality of semantic reasoning via the ontology was demonstrated with a case study based on curriculum development. The output of the modelling results demonstrated that the ontology could be successfully utilised for this purpose and this is discussed in relation to practicality and future direction.
Elidottir K, Elliot C, Lee J, Gutierrez , Velliou V, Bussemaker Madeleine (2017) The effect of ultrasound on the inactivation of Listeria innocua cells in gel mediums,
Bussemaker Madeleine, Day K, Drage G, Cecelja Franjo (2015) A value chain optimization model for a biorefinery with feedstock and product choices,
Nalesso Silvia, Bussemaker Madeleine J., Sear Richard P., Hodnett Mark, Lee Judy (2019) A Review on Possible Mechanisms of Sonocrystallisation in Solution, Ultrasonics Sonochemistry Elsevier
Sonocrystallisation is the application of ultrasound to the crystallisation process. The benefits obtained by sonication have been widely studied since the beginning of the 20th century and so far it is clear that ultrasound can be a very useful tool for enhancing crystallisation and controlling the properties of the final product. Crystal size, polymorphs, purity, process repeatability and lower induction time are only some of the advantages of sonocrystallisation. Even though the effects of sonication on crystallisation are quite clear, the physical explanation of the phenomena involved is still lacking. Is the presence of cavitation necessary for the process? Or is only the bubbles surface responsible for enhancing crystallisation? Are the strong local increases in pressure and temperature induced by cavitation the main cause of all the observed effects? Or is it the strong turbulence induced in the system, instead? Many questions still remain and can only be appreciated with an understanding of the complexity behind the individual processes of crystallisation and acoustic cavitation. Therefore, this review will first summarise the theories behind crystallisation and acoustic cavitation, followed by a description of all the current proposed sonocrystallisation mechanisms, and conclude with an overview on future prospects of sonocrystallisation applications.
Wood Richard James, Lee Judy, Bussemaker Madeleine J. (2019) Disparities between sonoluminescence, sonochemiluminescence and dosimetry with frequency variation under flow, Ultrasonics Sonochemistry Elsevier
The effects of ultrasound (frequency and pressure amplitude) and external parameters (fluid flow rate and surface stabilisation) on active sonoluminescence (SL) and sonochemical (SC) bubbles were investigated using common characterisation techniques. The SL from water, sonochemiluminescence (SCL) from luminol solutions and iodide dosimetry were studied at flow rates of 0, 24, 228 and 626 mL / min at 44, 300 and 1000 kHz with and without surface stabilisation. An increase in flow, in general, decreased SL, SCL and dosimetry caused by a reduction in collapse intensity. However, all flow rates were also able to increase SL intensity and the highest flow rate (626 mL / min) could also increase SCL and dosimetry. For SL, augmentation with flow was attributed to a reduction in coalescence bubbles which cause growth to inactive size (44 kHz) and enhancement of the standing wave at the surface of solution (300 and 1000 kHz). Where agitation at the solution surface (44 kHz) caused aeration (without stabilisation), flow may have circulated additional cavitation nuclei, increasing SL. Increases in SCL intensity and dosimetry yields were attributed to increased bubble fragmentation which was more influential for the latter process. Disparities between SCL and dosimetry are discussed in terms of gas concentration and reaction energy requirements influenced by the transient nature of the bubbles. SL and SCL had complimentary behaviour when they were located in the same regions i.e. a reduction in SL resulted in an increase in SCL as bubbles moved from stable to transient in nature. The same was not observed when SL and SCL bubbles were located in different regions. The active region for SL / SCL could differ or overlap, depending on the standing to travelling wave proportions at each frequency effecting active regions. In some cases, increased standing wave proportions throughout the reactor (with surface stabilisation) did not facilitate an increase in SL intensity, as was expected. Here, the travelling wave without stabilisation enabled a stronger area of activity toward the surface with a localised standing wave.
Wood Richard James, Lee Judy, Bussemaker Madeleine J. (2019) Combined effects of flow, surface stabilisation and salt concentration in aqueous solution to control and enhance sonoluminescence, Ultrasonics - Sonochemistry Elsevier
Sonoluminescence (SL) intensity can be increased with potassium iodide (KI) concentration, attributed to a reduction in the gas concentration of solution. However, bubble properties and active bubble distributions at different frequencies and powers also influence SL intensities. Hence, to elucidate how salt concentration affects SL intensity, a systematic study with parametric variation was undertaken. SL from KI solutions of 0.1, 1 and 2 M concentration, without flow and in the presence of flow at 24, 228 and 626 mL / min was investigated at 44, 300 and 1000 kHz. At all frequencies an increase in KI concentration caused a change in the active SL distributions. For 44 kHz, localised and standing wave field SL activity could be expanded. Flow at this frequency augmented SL and SL was maximised at the lowest power setting under stabilisation at the highest KI concentration. At 300 and 1000 kHz, attenuation of the sound field was reduced, allowing expansion of activity throughout solution. In this instance, augmentation of SL intensity was only observed under flow conditions at concentrations of 1 M (300 kHz) and 2 M (1000 kHz) under stabilisation. It was theorised that a combination of smaller bubbles at higher KI concentrations and flow effects could reduce bubble clustering and enhance field formations. This was most prevalent where the standing wave was reinforced under stabilised (44 and 300 kHz) or flow (1000 kHz) conditions, here the number of active bubbles in high pressure regions likely increases. Lastly, it was found that in KI solutions flow could localise SL activity beneath and at the flow inlet via reflection and aeration mechanisms.

In general, bubble surface instabilities (herein known as bubble transience), increase sonochemical (SC) processes and decrease processes, such as sonoluminescence (SL), that require higher collapse intensities. However, there is a limited understanding of how SL and SC processes are impacted by bubble transience in a practical sense. Thus, research and experimentation was based on the variation of parameters that would affect transience which, in turn, would determine ultrasound process outcomes.

Firstly, the ultrasonic system was characterised using SL, and the SC processes of sonochemiluminescence (SCL) and potassium iodide (KI) dosimetry. Frequencies of 20 kHz (ultrasonic horn) and 44, 300 and 1000 kHz (ultrasonic plates) were used with applied flow rates of 0, 24, 228 and 626 mL / min. These frequency and flow settings were used throughout the work unless otherwise specified. The SCL and dosimetry showed disparities throughout, attributed to changes in the energy of collapse, fragmentation and oxygen concentration / solvated electrons. At low frequency, SCL and dosimetry increased under more transient collapse conditions, as measured by the minimisation of the more pyrolytic process of SL. Here, it was theorised that bubble fragmentation and radical transfer to solution, favoured dosimetry over SCL. Further, where SL and SCL activity overlapped they showed the expected reciprocal relationship of decrease / increase with bubble transience, but where activity differed there was poor correlation.

Then, the impact of bubble transience on the intensity of collapse on SL from KI solutions (0.1, 1 and 2 M) under fluid flow and stabilised conditions were studied. At 20 kHz (horn) and 44 kHz (plate), flow reduced bubble coalescence and clustering, increasing SL intensity. However, for the 44 kHz system, at higher flow rates, bubble transience could also reduce SL. With an increase in KI concentration, at low frequency (44 kHz), localised activity could be expanded, then at higher frequencies (300 and 1000 kHz), SL activity increased towards the transducer. This indicated reduced attenuation of the sound field, attributed to a reduction in bubble size / clustering with the salt. An increase in standing wave formations (plate) or activity at the horn tip, with power (20 kHz), stabilisation (44 and 300 kHz) or flow (1000 kHz), allowed flow and salt concentration to reduce bubble coalescence / clustering in those regions. This effect could negate a decrease in SL, with increase in KI concentration at low frequency, as previously observed by other authors.

To understand how bubble transience affected SC and SL processes, the degradation of phenol and SL from phenol under fluid flow (and stabilised) conditions was investigated. Flow could augment phenol degradation at all frequencies. For the 20 kHz (horn) and 300 kHz systems, phenol degradation correlated with iodide dosimetry which suggested an oxidative process, however, 44 and 1000 kHz showed poor correlation. At 44 kHz, degradation was hypothesised to occur inside the bubbles under transient (flow) bubble conditions, as indicated by SL quenching when degradation was maximised. This was theorised to occur via nanodroplet / rectified diffusion mechanisms. At 1000 kHz the disparity between phenol degradation and iodide dosimetry was attributed to a reduction in collapse intensity and fragmentation which affected the reaction schemes. Here, the fragmentation conditions with flow were not sufficient to increase the dosimetry, whereas for degradation, fragmentation was less influential. SL analysis for higher concentrations of phenol (horn and plate transducers) showed that intensity could be increased with flow / stabilisation. This was attributed a reduction in coalescence / clustering by both flow and the surface properties of the phenol.

The methods of SC and SL characterisation were then applied to further understand the ultrasonic degradation of