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Dr GEORGIOS DIMITRAKIS's Outputs (44)

Dynamic Superficial Dielectric Constant Models and Void Fraction Prediction by Microwave Resonant Cavity for Gas Liquid Flow (2025)
Journal Article
Yang, Y., Liu, M., Liu, J., Xu, Y., Ma, H., Liu, Y., Yuan, C., Hewakandamby, B., & Dimitrakis, G. (in press). Dynamic Superficial Dielectric Constant Models and Void Fraction Prediction by Microwave Resonant Cavity for Gas Liquid Flow. IEEE Transactions on Instrumentation and Measurement,

In the investigation of non-uniform flow measurement utilizing microwave technologies, both the dielectric properties and phase fraction of the flow are crucial factors. This study introduces a new concept of dynamic superficial dielectric constant (... Read More about Dynamic Superficial Dielectric Constant Models and Void Fraction Prediction by Microwave Resonant Cavity for Gas Liquid Flow.

A novel method for fast and efficient numerical simulation of microwave heating in liquids during mixing (2024)
Journal Article
Singh, B., Hefford, S., Sanchez-Perez, E., Barter, M., Slocombe, D. R., Cussen, S. A., & Dimitrakis, G. (2025). A novel method for fast and efficient numerical simulation of microwave heating in liquids during mixing. International Journal of Heat and Mass Transfer, 237, Article 126425. https://doi.org/10.1016/j.ijheatmasstransfer.2024.126425

Microwave-assisted chemical reactions present potentially more sustainable routes for process intensification compared with traditional approaches, due to the reduction of reaction times, temperatures, and side reactions. Despite the common misconcep... Read More about A novel method for fast and efficient numerical simulation of microwave heating in liquids during mixing.

State-of-the-art in microwave processing of metals, metal powders and alloys (2024)
Journal Article
Hossain, F., Turner, J. V., Wilson, R., Chen, L., de Looze, G., Kingman, S. W., Dodds, C., & Dimitrakis, G. (2024). State-of-the-art in microwave processing of metals, metal powders and alloys. Renewable and Sustainable Energy Reviews, 202, Article 114650. https://doi.org/10.1016/j.rser.2024.114650

Discovery of the capacity of microwave energy to heat materials was a major milestone in the history of technology and scientific research. This discovery led to the development of many devices and processes that have replaced conventional heating me... Read More about State-of-the-art in microwave processing of metals, metal powders and alloys.

Coaxial Dielectric Spectroscopy as an In-Line Process Analytical Technique for Reaction Monitoring (2023)
Journal Article
Dalligos, D. M., Pilling, M. J., Dimitrakis, G., & Ball, L. T. (2023). Coaxial Dielectric Spectroscopy as an In-Line Process Analytical Technique for Reaction Monitoring. Organic Process Research and Development, 27(6), 1094-1103. https://doi.org/10.1021/acs.oprd.3c00081

The suitability of broadband dielectric spectroscopy (DS) as a tool for in-line (in situ) reaction monitoring is demonstrated. Using the esterification of 4-nitrophenol as a test-case, we show that multivariate analysis of time-resolved DS data – col... Read More about Coaxial Dielectric Spectroscopy as an In-Line Process Analytical Technique for Reaction Monitoring.

Ring opening polymerisation of ɛ-caprolactone with novel microwave magnetic heating and cyto-compatible catalyst (2023)
Journal Article
Wang, K., Ni, M., Dundas, A. A., Dimitrakis, G., & Irvine, D. J. (2023). Ring opening polymerisation of ɛ-caprolactone with novel microwave magnetic heating and cyto-compatible catalyst. Frontiers in Bioengineering and Biotechnology, 11, Article 1123477. https://doi.org/10.3389/fbioe.2023.1123477

We report on the ring-opening polymerization of ɛ-caprolactone incorporated with a magnetic susceptible catalyst, FeCl3, via the use of microwave magnetic heating (HH) which primarily heats the bulk with a magnetic field (H-field) from an electromagn... Read More about Ring opening polymerisation of ɛ-caprolactone with novel microwave magnetic heating and cyto-compatible catalyst.

Small Bubbles Formation and Contribution to the Overall Gas Holdup in Large Diameter Columns of Very High Viscosity Oil (2022)
Journal Article
Mohammed, S. K., Hasan, A. H., Dimitrakis, G., & Azzopardi, B. J. (2022). Small Bubbles Formation and Contribution to the Overall Gas Holdup in Large Diameter Columns of Very High Viscosity Oil. International Journal of Multiphase Flow, 152, Article 104104. https://doi.org/10.1016/j.ijmultiphaseflow.2022.104104

A limited number of studies are available in literature on the small bubbles which create from gas-very high viscosity oils interaction and its contribution to the gas holdup in the system. The rate of small bubble formation has an important impact o... Read More about Small Bubbles Formation and Contribution to the Overall Gas Holdup in Large Diameter Columns of Very High Viscosity Oil.

An experimental study on the effect of gas injection configuration on flow characteristics in high viscosity oil columns (2021)
Journal Article
Mohammed, S. K., Hasan, A. H., Ibrahim, A., & Dimitrakis, G. (2021). An experimental study on the effect of gas injection configuration on flow characteristics in high viscosity oil columns. Canadian Journal of Chemical Engineering, 100(10), 3015-3029. https://doi.org/10.1002/cjce.24312

Gas-viscous liquid bubbly and slug flow are very common in petroleum, chemical, bioengineering, polymer, and food processing. However, there is a major knowledge gap in two-phase flow research in the design of gas injectors/distributers in very high... Read More about An experimental study on the effect of gas injection configuration on flow characteristics in high viscosity oil columns.

Evaluation of Microwave Applicator Design on Electromagnetic Field Distribution and Heating Pattern of Cooked Peeled Shrimp (2021)
Journal Article
Siguemoto, É. S., Gut, J. A. W., Dimitrakis, G., Curet, S., & Boillereaux, L. (2021). Evaluation of Microwave Applicator Design on Electromagnetic Field Distribution and Heating Pattern of Cooked Peeled Shrimp. Foods, 10(8), Article 1903. https://doi.org/10.3390/foods10081903

Non-uniform temperature distribution within solid food is a major problem associated with microwave heating, which limits industrial applications. Therefore, an experimentally validated 3D model was proposed to study the effect of microwave applicato... Read More about Evaluation of Microwave Applicator Design on Electromagnetic Field Distribution and Heating Pattern of Cooked Peeled Shrimp.

Effects of the heating source on the regeneration performance of different adsorbents under post-combustion carbon capture cyclic operations. A comparative analysis (2021)
Journal Article
Yassin, M., Anderson, J., Dimitrakis, G., & Martín, C. (2021). Effects of the heating source on the regeneration performance of different adsorbents under post-combustion carbon capture cyclic operations. A comparative analysis. Separation and Purification Technology, 276, Article 119326. https://doi.org/10.1016/j.seppur.2021.119326

This work presents a comparative study of microwave and conventional (conductive) heating for adsorbent regeneration. A binary gas mixture representative of pre-dried flue gas from coal-fired power plants (15% v/v CO2 in N2) was passed through a rota... Read More about Effects of the heating source on the regeneration performance of different adsorbents under post-combustion carbon capture cyclic operations. A comparative analysis.

Microstructure and tensile properties of additive manufactured Ti-6Al-4V with refined prior-β grain structure obtained by rapid heat treatment (2021)
Journal Article
Zou, Z., Simonelli, M., Katrib, J., Dimitrakis, G., & Hague, R. (2021). Microstructure and tensile properties of additive manufactured Ti-6Al-4V with refined prior-β grain structure obtained by rapid heat treatment. Materials Science and Engineering: A, 814, Article 141271. https://doi.org/10.1016/j.msea.2021.141271

Heat treatments tailored for additive manufactured Ti-6Al-4V can be used to attain desirable microstructures associated with superior mechanical properties. Rapid heat treatments, for example, can be used to recrystallise the microstructure of laser... Read More about Microstructure and tensile properties of additive manufactured Ti-6Al-4V with refined prior-β grain structure obtained by rapid heat treatment.

Mathematical modelling of dielectric properties of food with respect to moisture content using adapted water activity equations (2021)
Journal Article
Renshaw, R. C., Dimitrakis, G. A., & Robinson, J. P. (2021). Mathematical modelling of dielectric properties of food with respect to moisture content using adapted water activity equations. Journal of Food Engineering, 300, Article 110538. https://doi.org/10.1016/j.jfoodeng.2021.110538

There is currently no recognised equation, or set of equations, that can be used to adequately describe moisture dependant dielectrics. This study addresses this issue so that moisture dependant dielectric properties can be directly input into drying... Read More about Mathematical modelling of dielectric properties of food with respect to moisture content using adapted water activity equations.

A new approach for the vitrification of municipal solid waste incinerator bottom ash by microwave irradiation (2020)
Journal Article
Flesoura, G., Dilissen, N., Dimitrakis, G., Vleugels, J., & Pontikes, Y. (2021). A new approach for the vitrification of municipal solid waste incinerator bottom ash by microwave irradiation. Journal of Cleaner Production, 284, Article 124787. https://doi.org/10.1016/j.jclepro.2020.124787

Encouraging the transition to a circular economy, the valorization of municipal solid waste incinerator (MSWI) bottom ash (BA) has received considerable attention in many processes. In the present work, flash microwave vitrification was effectively r... Read More about A new approach for the vitrification of municipal solid waste incinerator bottom ash by microwave irradiation.

Microwave assisted sintering of Na-β’’-Al2O3 in single mode cavities: Insights in the use of 2450 MHz frequency and preliminary experiments at 5800 MHz (2020)
Journal Article
Mortalò, C., Rosa, R., Veronesi, P., Fasolin, S., Zin, V., Deambrosis, S. M., Miorin, E., Dimitrakis, G., Fabrizio, M., & Leonelli, C. (2020). Microwave assisted sintering of Na-β’’-Al2O3 in single mode cavities: Insights in the use of 2450 MHz frequency and preliminary experiments at 5800 MHz. Ceramics International, 46(18, Part A), 28767-28777. https://doi.org/10.1016/j.ceramint.2020.08.039

Microwave assisted sintering of Na-beta’’-Al2O3 in single mode cavities was accurately investigated. The use of single mode cavity allowed monitoring the parameters affecting the sintering process, like the forward power, together with the temperatur... Read More about Microwave assisted sintering of Na-β’’-Al2O3 in single mode cavities: Insights in the use of 2450 MHz frequency and preliminary experiments at 5800 MHz.

Refinement of the grain structure of additive manufactured titanium alloys via epitaxial recrystallization enabled by rapid heat treatment (2020)
Journal Article
Zou, Z., Simonelli, M., Katrib, J., Dimitrakis, G., & Hague, R. (2020). Refinement of the grain structure of additive manufactured titanium alloys via epitaxial recrystallization enabled by rapid heat treatment. Scripta Materialia, 180, 66-70. https://doi.org/10.1016/j.scriptamat.2020.01.027

The coarse prior-β grain structure in titanium alloys produced by additive manufacturing is associated to mechanical anisotropy and limited fatigue life. Here we report a novel methodology to refine such structure by rapid heat treatment of Ti-6Al-4V... Read More about Refinement of the grain structure of additive manufactured titanium alloys via epitaxial recrystallization enabled by rapid heat treatment.

The use of free-space microwave non-destructive techniques: simulation of damage detection in carbon fibre reinforced composites (2019)
Presentation / Conference Contribution
Munalli, D., Dimitrakis, G., Chronopoulos, D., Greedy, S., & Long, A. (2019, November). The use of free-space microwave non-destructive techniques: simulation of damage detection in carbon fibre reinforced composites. Presented at 11th Symposium on NDT in Aerospace, Paris, France

Microwave non-destructive testing (MNDT) methods represent an effective solution in detecting defects within composite structures with relatively low electrical conductivity. They offer the advantage to overcome the problems of traditional NDT techni... Read More about The use of free-space microwave non-destructive techniques: simulation of damage detection in carbon fibre reinforced composites.

Validating a Predictive Structure-Property Relationship by Discovery of Novel Polymers which Reduce Bacterial Biofilm Formation (2019)
Journal Article
Dundas, A. A., Sanni, O., Dubern, J.-F., Dimitrakis, G., Hook, A. L., Irvine, D. J., Williams, P., & Alexander, M. R. (2019). Validating a Predictive Structure-Property Relationship by Discovery of Novel Polymers which Reduce Bacterial Biofilm Formation. Advanced Materials, 31(49), Article 1903513. https://doi.org/10.1002/adma.201903513

ynthetic materials are an everyday component of modern healthcare yet often fail routinely as a consequence of medical‐device‐centered infections. The incidence rate for catheter‐associated urinary tract infections is between 3% and 7% for each day o... Read More about Validating a Predictive Structure-Property Relationship by Discovery of Novel Polymers which Reduce Bacterial Biofilm Formation.

Dynamics of flow transitions from bubbly to churn flow in high viscosity oils and large diameter columns (2019)
Journal Article
Mohammed, S. K., Hasan, A. H., Ibrahim, A., Dimitrakis, G., & Azzopardi, B. J. (2019). Dynamics of flow transitions from bubbly to churn flow in high viscosity oils and large diameter columns. International Journal of Multiphase Flow, 120, Article 103095. https://doi.org/10.1016/j.ijmultiphaseflow.2019.103095

The dynamic behaviour of the gas-liquid two phase flows and in particular the flow pattern stability and transition between the flow regimes are influenced significantly by both the properties of the liquid and gas as well as the pipe diameter. The m... Read More about Dynamics of flow transitions from bubbly to churn flow in high viscosity oils and large diameter columns.

Optimised mode selection in electromagnetic sensors for real time, continuous and in-situ monitoring of water cut in multi-phase flow systems (2019)
Journal Article
Yuan, C., Bowler, A., Davies, J. G., Hewakandamby, B., & Dimitrakis, G. (2019). Optimised mode selection in electromagnetic sensors for real time, continuous and in-situ monitoring of water cut in multi-phase flow systems. Sensors and Actuators B: Chemical, 298, Article 126886. https://doi.org/10.1016/j.snb.2019.126886

Measurements of the composition of multiphase flows, especially water-cut in oil-water flow, is a frequently encountered problem in the petroleum industry. New techniques that can offer improvements towards that are continuously sought and the use of... Read More about Optimised mode selection in electromagnetic sensors for real time, continuous and in-situ monitoring of water cut in multi-phase flow systems.

Methodology for the synthesis of methacrylate monomers using designed single mode microwave applicators (2019)
Journal Article
Dundas, A. A., Hook, A. L., Alexander, M. R., Kingman, S. W., Dimitrakis, G., & Irvine, D. J. (2019). Methodology for the synthesis of methacrylate monomers using designed single mode microwave applicators. Reaction Chemistry and Engineering, 4(8), 1472-1476. https://doi.org/10.1039/c9re00173e

© 2019 The Royal Society of Chemistry. A novel single-well prototype high throughput microwave reactor geometry has been produced and shown to be capable of synthesizing an array of non-commercially available methacrylate monomers. The reactor, which... Read More about Methodology for the synthesis of methacrylate monomers using designed single mode microwave applicators.