Professor James Njuguna's Outputs (121)

Structural and thermal degradation behaviour of reclaimed clay nano-reinforced low density polyethylene nanocomposites. (2019)
Journal Article
SIDDIQUE, S., SMITH, G.D., YATES, K., MISHRA, A.K., MATTHEWS, K., CSETENYI, L.J. and NJUGUNA, J. 2019. Structural and thermal degradation behaviour of reclaimed clay nano-reinforced low-density polyethylene nanocomposites. Journal of polymer research [online], 26, article ID 154. Available from: https://doi.org/10.1007/s10965-019-1802-9

In this study, a novel reclaimed clay nanofiller used to manufacture low-density polyethylene (LDPE)/Oil based mud fillers (OBMFs) nanocomposites by a melt compounding process. The mechanical testing samples were manufactured using injection mouldin... Read More about Structural and thermal degradation behaviour of reclaimed clay nano-reinforced low density polyethylene nanocomposites..

Influence of reduced graphene oxide on epoxy/carbon fibre-reinforced hybrid composite: flexural and shear properties under varying temperature conditions. (2019)
Journal Article
JENKINS, P., SIDDIQUE, S., KHAN, S., USMAN, A., STAROST, K., MACPHERSON, A., BARI, P., MISHRA, S. and NJUGUNA, J. 2019. Influence of reduced graphene oxide on epoxy/carbon fibre-reinforced hybrid composite: flexural and shear properties under varying temperature conditions. Advanced engineering materials [online], 21(6), article ID 1800614. Available from: https://doi.org/10.1002/adem.201800614

This study investigated the effectiveness of reduced graphene oxide as nanofiller in enhancing epoxy/carbon fibre-reinforced composite at varying temperature conditions. The graphene oxide was synthesised using modified Hummer’s method and then chemi... Read More about Influence of reduced graphene oxide on epoxy/carbon fibre-reinforced hybrid composite: flexural and shear properties under varying temperature conditions..

The crystallinity and thermal degradation behaviour of polyamide 6/oil based mud fillers (PA6/OBMFs) nanocomposites. (2018)
Journal Article
SIDDIQUE, S., KWOFFIE, L., ADDAE-AFOAKWA, K., YATES, K. and NJUGUNA, J. 2019. The crystallinity and thermal degradation behaviour of polyamide 6/oil based mud fillers (PA6/OBMFs) nanocomposites. Polymer degradation and stability [online], 159, pages 139-152. Available from: https://doi.org/10.1016/j.polymdegradstab.2018.11.004

The crystallinity and thermal degradation behaviours of Polyamide 6/Oil Based Mud Fillers (PA6/OBMFs) nanocomposites have been investigated using DSC and TGA. TGA indicates the onset decomposition temperature of D1/2 (half-decomposition) is 16º C hig... Read More about The crystallinity and thermal degradation behaviour of polyamide 6/oil based mud fillers (PA6/OBMFs) nanocomposites..

Sustainable energy for emerging nations development: a case study on Togo renewable energy. (2018)
Presentation / Conference Contribution
KANSONGUE, N., NJUGUNA, J. and VERTIGANS, S. 2018. Sustainable energy for emerging nations development: a case study on Togo renewable energy. In Proceedings of the Institute of Electrical and Electronics Engineers (IEEE) Power and Energy Society (PES) and Industrial Applications Society (IAS) PowerAfrica 2018 conference, 26-29 June 2018, Cape Town, South Africa. Piscataway, NJ: IEEE [online], pages 137-141. Available from: https://doi.org/10.1109/PowerAfrica.2018.8521054

This paper explores the need for an appropriate energy delivery, placing emphasis on the role of the indigenous people in developing their future needs. The case study is based on Togo renewable energy sustainability and employs qualitative and quant... Read More about Sustainable energy for emerging nations development: a case study on Togo renewable energy..

Characterisation of oil based mud waste to explore the possibility in transforming waste into a value added product. (2018)
Presentation / Conference Contribution
SIDDIQUE, S., YATES, K. and NJUGUNA, J. 2018. Characterisation of oil based mud waste to explore the possibility in transforming waste into a value added product. Presented at the 6th International conference on sustainable solid waste management (NAXOS 2018), 13-16 June 2018, Naxos, Greece. Athens: National Technical University of Athens [online], paper number 45. Available from: http://uest.ntua.gr/naxos2018/proceedings/pdf/45_NAXOS2018_Siddique_etal.pdf

Waste characterisation is an essential factor in designing sustainable waste management plan. However, waste composition profile is underestimated in oil and gas exploration and production (E&P) industries in the United Kingdom. A three years long in... Read More about Characterisation of oil based mud waste to explore the possibility in transforming waste into a value added product..

Abstract book for the proceedings of the 4th International conference on structural nano composites (NANOSTRUC 2018), 23-24 May 2018, Berlin, Germany. (2018)
Presentation / Conference Contribution
NJUGUNA, J. and NGO, H.-D. (eds.) 2018. Abstract book for the proceedings of the 4th International conference on structural nano composites (NANOSTRUC 2018), 23-24 May 2018, Berlin, Germany [online]. Available from: https://www.nanostruc.info/nanostruc-conference.html

The purpose of The 4th International Conference on Structural Nano Composites (NANOSTRUC2018) is to promote activities in various areas of materials and structures by providing a forum for exchange of ideas, presentation of technical achievements and... Read More about Abstract book for the proceedings of the 4th International conference on structural nano composites (NANOSTRUC 2018), 23-24 May 2018, Berlin, Germany..

Mechanical, thermal, and flammability behaviour of low density polyethylene - oil based mud fillers nanocomposites. (2018)
Presentation / Conference Contribution
SIDDIQUE, S., SMITH, G.D., YATES, K. and NJUGUNA, J. 2018. Mechanical, thermal, and flammability behaviour of low density polyethylene - oil based mud fillers nanocomposites. Presented at the 4th International conference on structural nano composites (NANOSTRUC 2018), 23-24 May 2018, Berlin, Germany.

Novel low density polyethylene (LDPE)/Oil based mud fillers (OBMF) nanocomposites were manufactured by a melt compounding process. Fourier Transform Infrared (FTIR) Spectroscopy was used to characterise the structure of the nanocomposites. The result... Read More about Mechanical, thermal, and flammability behaviour of low density polyethylene - oil based mud fillers nanocomposites..

Cross sensitivity analysis of optical fibre-based sensing for high pressure, high temperature measurement in oil and gas applications. (2018)
Thesis
AMOS, S.U. 2018. Cross sensitivity analysis of optical fibre-based sensing for high pressure, high temperature measurement in oil and gas applications. Robert Gordon University, PhD thesis.

Measurements of physical parameters like pressure, temperature, flow rate, vibrations and displacement in harsh environment are often desired in the oil and gas industry. Pressure and temperature are the most important parameters among them. Changes... Read More about Cross sensitivity analysis of optical fibre-based sensing for high pressure, high temperature measurement in oil and gas applications..

Mechanical structural design of a MEMS-based piezoresistive accelerometer for head injuries monitoring: a computational analysis by increments of the sensor mass moment of inertia. (2018)
Journal Article
MESSINA, M., NJUGUNA, J. and PALAS, C. 2018. Mechanical structural design of a MEMS-based piezoresistive accelerometer for head injuries monitoring: a computational analysis by increments of the sensor mass moment of inertia. Sensors [online], 18(1), article number 289. Available from: https://doi.org/10.3390/s18010289

This work focuses on the proof-mass mechanical structural design improvement of a tri-axial piezoresistive accelerometer specifically designed for head injuries monitoring where medium-G impacts are common; for example, in sports such as racing cars... Read More about Mechanical structural design of a MEMS-based piezoresistive accelerometer for head injuries monitoring: a computational analysis by increments of the sensor mass moment of inertia..

Removal of lead (II) from aqeouos waste using (CD-PCL-TiO2) bio-nanocomposites. (2017)
Journal Article
SEEMA, K.M., MAMBA, B.B., NJUGUNA, J., BAKHTIZIN, R.Z. and MISHRA, A.K. 2018. Removal of lead (II) from aqeouos waste using (CD-PCL-TiO2) bio-nanocomposites. International journal of biological macromolecules [online], 109, pages 136-142. Available from: https://doi.org/10.1016/j.ijbiomac.2017.12.046

Lead (Pb) pollution is our water system is a major concern, as this metal is toxic even at low concentration. This study aim to fabricate a bio-nanocomposite (cyclodextrin-polycaprolactone titanium dioxide) that will be used as an adsorbent for the r... Read More about Removal of lead (II) from aqeouos waste using (CD-PCL-TiO2) bio-nanocomposites..

Insulating polymer nanocomposites for high thermal conduction and fire retarding applications. (2017)
Presentation / Conference Contribution
GUPTA, R., HUO, D., PANCHOLI, M., NJUGUNA, J. and PANCHOLI, K. 2017. Insulating polymer nanocomposites for high thermal conduction and fire retarding applications. Presented at the 3rd Defence and security doctoral symposium, 14-15 November 2017, Swindon, UK [online]. Available from: https://doi.org/10.17862/cranfield.rd.5675281.v1

The possibility of combining the flexibility and light - weight of polymers with the highest insulation of ceramics, drives the field of nanocomposites for potential commercial application. The inclusion of nano-sized insulating particles in the poly... Read More about Insulating polymer nanocomposites for high thermal conduction and fire retarding applications..

Computational analysis and optimization of a MEMS-based piezoresistive accelerometer for head injuries monitoring. (2017)
Presentation / Conference Contribution
MESSINA, M., NJUGUNA, J. and PALAS, C. 2017. Computational analysis and optimization of a MEMS-based piezoresistive accelerometer for head injuries monitoring. In Proceedings of the 2017 IEEE sensors conference, 29 October - 1 November 2017, Glasgow, UK. New York: IEEE [online], article number 8233897, pages 91-93. Available from: https://doi.org/10.1109/ICSENS.2017.8233897

This work focuses on the design improvement of a tri-axial piezoresistive accelerometer specifically designed for head injuries monitoring where medium-G impacts are common, for example in sports such as racing cars. The device requires the highest s... Read More about Computational analysis and optimization of a MEMS-based piezoresistive accelerometer for head injuries monitoring..

Computational analysis and optimization of a MEMS-based piezoresistive accelerometer for head injuries monitoring. (2017)
Presentation / Conference Contribution
MESSINA, M., NJUGUNA, J. and PALAS, C. 2017. Computational analysis and optimization of a MEMS-based piezoresistive accelerometer for head injuries monitoring. Presented at the 2017 IEEE sensors conference, 29 October - 1 November 2017, Glasgow, UK.

This work focuses on the design improvement of a tri-axial piezoresistive accelerometer specifically designed for head injuries monitoring where medium-G impacts are common, for example in sports such as racing cars. The device requires the highest s... Read More about Computational analysis and optimization of a MEMS-based piezoresistive accelerometer for head injuries monitoring..

Assessment of nanoparticles release into the environment during drilling of carbon nanotubes/epoxy and carbon nanofibres/epoxy nanocomposites. (2017)
Journal Article
STAROST, K., FRIJNS, E., VAN LAER, J., FAISAL, N., EGIZABAL, A., ELIZEXTEA, C., BLAZQUEZ, M., NELISSEN, I. and NJUGUNA, J. 2017. Assessment of nanoparticles release into the environment during drilling of carbon nanotubes/epoxy and carbon nanofibres/epoxy nanocomposites. Journal of hazardous materials [online], 340, pages 57-66. Available from: https://doi.org/10.1016/j.jhazmat.2017.06.057

The risk assessment, exposure and understanding of the release of embedded carbon nanotubes (CNTs) and carbon nanofibers (CNFs) from commercial high performance composites during machining processes is yet to be fully evaluated and quantified. In thi... Read More about Assessment of nanoparticles release into the environment during drilling of carbon nanotubes/epoxy and carbon nanofibres/epoxy nanocomposites..

Theoretical design and analysis of a sensing system for high pressure and temperature measurement in subsea underwater applications. (2017)
Presentation / Conference Contribution
AMOS, S., PRABHU, R. and NJUGUNA, J. 2017. Theoretical design and analysis of a sensing system for high pressure and temperature measurement in subsea underwater applications. In Proceedings of OCEANS 2017, 19-22 June 2017, Aberdeen, UK. New York: IEEE [online], article number 8085023, pages 2680-2686. Available from: https://doi.org/10.1109/OCEANSE.2017.8085023

The theoretical design and analysis of a metal coated hybrid sensing system of Fibre Bragg Grating (FBG) and Extrinsic Fabry-Perot Interferometer (EFPI) cavity for high pressure high temperature (HPHT) measurement in subsea underwater applications is... Read More about Theoretical design and analysis of a sensing system for high pressure and temperature measurement in subsea underwater applications..

The effect of nanosilica (SiO2) and nanoalumina (Al2O3) reinforced polyester nanocomposites on aerosol nanoparticle emissions into the environment during automated drilling. (2017)
Journal Article
STAROST, K., FRIJNS, E., VAN LAER, J., FAISAL, N., EGIZABAL, A., ELIZEXTEA, C., NEILSSEN, I., BALZQUEZ, M. and NJUGUNA, J. 2017. The effect of nanosilica (SiO2) and nanoalumina (Al2O3) reinforced polyester nanocomposites on aerosol nanoparticle emissions into the environment during automated drilling. Aerosol science and technology [online], 51(9), pages 1035-1046. Available from: https://doi.org/10.1080/02786826.2017.1330535

The aim of this study is to investigate the effect nanosilica and nanoalumina has on nanoparticle release from industrial nanocomposites due to drilling for hazard reduction whilst simultaneously obtaining the necessary mechanical performance. This s... Read More about The effect of nanosilica (SiO2) and nanoalumina (Al2O3) reinforced polyester nanocomposites on aerosol nanoparticle emissions into the environment during automated drilling..

Elaboration of properties of graphene oxide reinforced epoxy nanocomposites. (2017)
Journal Article
BARI, P., KHAN, S., NJUGUNA, J. and MISHRA, S. 2017. Elaboration of properties of graphene oxide reinforced epoxy nanocomposites. International journal of plastics technology [online], 21(1), pages 194-208. Available from: https://doi.org/10.1007/s12588-017-9180-9

In this research work, properties of graphene oxide (GO) based epoxy nanocomposites, prepared via the solution blending method, are elaborated. Different loadings (0.1-0.5 wt%) of GO were added into epoxy resin, and their effects were studied on thei... Read More about Elaboration of properties of graphene oxide reinforced epoxy nanocomposites..

Oil based drilling fluid waste: an overview on environmentally persistent pollutants. (2017)
Presentation / Conference Contribution
SIDDIQUE, S., KWOFFIE, L., ADDAE-AFOAKWA, K., YATES, K. and NJUGUNA, J. 2016. Oil based drilling fluid waste: an overview on environmentally persistent pollutants. IOP conference series: materials science and engineering [online], 195: proceedings of the 3rd International conference on structural nano composites (NANOSTRUC 2016), 12-16 September 2016, Aberdeen, UK, article number 012008. Available from: https://doi.org/10.1088/1757-899X/195/1/012008

Operational discharges of spent drilling fluid, produced water, and accumulated drill cuttings from oil and gas industry are a continuous point source of environmental pollution. To meet the strict environmental standard for waste disposal, oil and g... Read More about Oil based drilling fluid waste: an overview on environmentally persistent pollutants..

Tensile and flexural properties of hybrid graphene oxide/epoxy carbon fibre reinforced composites. (2017)
Presentation / Conference Contribution
WATSON, G., STAROST, K., BARI, P., FAISAL, N., MISHRA, S. and NJUGUNA, J. 2016. Tensile and flexural properties of hybrid graphene oxide/epoxy carbon fibre reinforced composites. IOP conference series: materials science and engineering [online], 195: proceedings of the 3rd International conference on structural nano composites (NANOSTRUC 2016), 12-16 September 2016, Aberdeen, UK, article number 012009. Available from: https://doi.org/10.1088/1757-899X/195/1/012009

In this study, nano-sized graphene oxide sheets were homogenously dispersed via sonication methods in epoxy followed by vacuum resin infusion for the fabrication of the epoxy, graphene oxide (GO) and micro-sized carbon fibre reinforced nanocomposites... Read More about Tensile and flexural properties of hybrid graphene oxide/epoxy carbon fibre reinforced composites..

Environmental particle emissions due to automated drilling of polypropylene composites and nanocomposites reinforced with talc, montmorillonite and wollastonite. (2017)
Presentation / Conference Contribution
STAROST, K., FRIJNS, E., LAER, J.V., FAISAL, N., EGIZABAL, A., ELIZEXTEA, C., NELISSEN, I., BLAZQUEZ, M. and NJUGUNA, J. 2016. Environmental particle emissions due to automated drilling of polypropylene composites and nanocomposites reinforced with talc, montmorillonite and wollastonite. IOP conference series: materials science and engineering [online], 195: proceedings of the 3rd International conference on structural nano composites (NANOSTRUC 2016), 12-16 September 2016, Aberdeen, UK, article number 012011. Available from: https://doi.org/10.1088/1757-899X/195/1/012011

In this study, the effect on nanoparticle emissions due to drilling on Polypropylene (PP) reinforced with 20% talc, 5% montmorillonite (MMT) and 5% Wollastonite (WO) is investigated. The study is the first to explore the nanoparticle release from WO... Read More about Environmental particle emissions due to automated drilling of polypropylene composites and nanocomposites reinforced with talc, montmorillonite and wollastonite..