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  • 1.
    Babu, NB Karthik
    et al.
    Department of Mechanical Engineering, Assam Energy Institute, A Centre of Rajiv Gandhi Institute of Petroleum Technology, Sivasagar, India.
    Mensah, Rhoda Afriyie
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Shanmugam, Vigneshwaran
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Rashedi, Ahmad
    School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore, Singapore.
    Athimoolam, Pugazhenthi
    Department of Mechanical Engineering, University College of Engineering Dindigul, Dindigul, India.
    Aseer, J. Ronald
    Department of Mechanical Engineering, National Institute of Technology Puducherry, Karaikal, India.
    Das, Oisik
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Self‐reinforced polymer composites: An opportunity to recycle plastic wastes and their future trends2022Inngår i: Journal of Applied Polymer Science, ISSN 0021-8995, E-ISSN 1097-4628, Vol. 139, nr 46, artikkel-id e53143Artikkel, forskningsoversikt (Fagfellevurdert)
    Abstract [en]

    Polymers and their composites have played an important role in industrial development. Polymer composites are becoming much stronger and more competitive than other materials as a result of ongoing research and development. This was made possible by newly developed techniques that could alter the physical and chemical properties of constituents. One of them is the self-reinforcement technique, which allows for the fabrication of high-strength thermoplastic polymer composites with reserved degradability, which is not possible with glass fiber/carbon fiber reinforcement. A self-reinforced polymer composite is made of a single polymeric material, which serves as both the matrix and the reinforcement. This review article discusses the use of self-reinforcement in various polymers and its impact on mechanical, thermal, and fire properties. Furthermore, the effects of process parameters (such as temperature and time, an), reinforcement structure, and mechanical property variation on the structure of self-reinforced composites are reviewed and presented in detail. In addition, the effect of foreign filler addition (such as flame retardants, inorganic particles, natural fibers, etc.) on self-reinforced composites is highlighted. In the end, the need for future research and its scope is presented.

  • 2.
    Birdsong, Björn K.
    et al.
    Department of Fiber and Polymer Technology, School of Chemical Science and Engineering, KTH Royal Institute of Technology, SE-100 44 Stockholm, Sweden.
    Wu, Qiong
    Department of Fiber and Polymer Technology, School of Chemical Science and Engineering, KTH Royal Institute of Technology, SE-100 44 Stockholm, Sweden.
    Hedenqvist, Mikael S.
    Department of Fiber and Polymer Technology, School of Chemical Science and Engineering, KTH Royal Institute of Technology, SE-100 44 Stockholm, Sweden.
    Capezza, Antonio J.
    Department of Fiber and Polymer Technology, School of Chemical Science and Engineering, KTH Royal Institute of Technology, SE-100 44 Stockholm, Sweden.
    Andersson, Richard L.
    Department of Fiber and Polymer Technology, School of Chemical Science and Engineering, KTH Royal Institute of Technology, SE-100 44 Stockholm, Sweden.
    Svagan, Anna J.
    Department of Fiber and Polymer Technology, School of Chemical Science and Engineering, KTH Royal Institute of Technology, SE-100 44 Stockholm, Sweden.
    Das, Oisik
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Mensah, Rhoda Afriyie
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Olsson, Richard T.
    Department of Fiber and Polymer Technology, School of Chemical Science and Engineering, KTH Royal Institute of Technology, SE-100 44 Stockholm, Sweden.
    Flexible and fire-retardant silica/cellulose aerogel using bacterial cellulose nanofibrils as template material2024Inngår i: Materials Advances, E-ISSN 2633-5409Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This study explores the possibility of using various silsesquioxane precursors such as (3-aminopropyl) triethoxysilane (APTES), methyltrimethoxysilane (MTMS), and tetraethyl orthosilicate (TEOS) to produce silsesquioxane-bacterial cellulose nanofibre (bCNF) aerogels. Each precursor allowed to customize the aerogel properties, leading to unique properties suitable for various applications requiring lightweight insulative materials. When utilizing APTES as the silsesquioxane precursor, an aerogel capable of over 90% recovery after compression was formed, making them suitable for flexible applications. When MTMS was used as the precursor, the aerogel retained some compression recovery (80%) but had the added property of superhydrophobicity with a contact angle over 160° due to the presence of CH3 functional groups, enabling water-repellence. Finally, TEOS allowed for excellent thermal insulative properties with a low Peak Heat Release Rate (PHRR), making it a promising candidate for fire-resistant applications. The customization of these aerogel materials was attributed to a combination of the chemical composition of the silsesquioxane precursors and the morphology of the coated bacterial cellulose nanofibres (bCNF), such as CH3 groups found in MTMS enabled for superhydrophobicity. Differences in morphology, such as uniform and smooth silsesquioxane coatings when using APTES or a “pearl-necklace” morphology using TEOS, enabled either compression recovery and flexibility or low thermal conduction. This investigation of silsesquioxane-bCNF provides a good understanding of the importance of the choice of precursor effect on insulating aerogel properties.

    Fulltekst (pdf)
    fulltext
  • 3.
    Das, Oisik
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Mensah, Rhoda Afriyie
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Balasubramanian, Karthik Babu Nilagiri
    Department of Mechanical Engineering, Assam Energy Institute, Centre of Rajiv Gandhi Institute of Petroleum Technology, 785697, Sivasagar, Assam, India.
    Shanmugam, Vigneshwaran
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Försth, Michael
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Hedenqvist, Mikael S
    Department of Fibre and Polymer Technology, KTH Royal Institute of Technology, SE-100 44 Stockholm, Sweden.
    Rantuch, Peter
    Faculty of Materials Science and Technology in Trnava, Slovak University of Technology in Bratislava, Jana Bottu 2781/25, 917 24 Trnava, Slovakia.
    Martinka, Jozef
    Faculty of Materials Science and Technology in Trnava, Slovak University of Technology in Bratislava, Jana Bottu 2781/25, 917 24 Trnava, Slovakia.
    Jiang, Lin
    School of Mechanical Engineering, Nanjing University of Science and Technology, 210094, Nanjing, China.
    Xu, Qiang
    School of Mechanical Engineering, Nanjing University of Science and Technology, 210094, Nanjing, China.
    Neisiany, Rasoul Esmaeely
    Department of Materials and Polymer Engineering, Faculty of Engineering, Hakim Sabzevari University, Sabzevar 9617976487, Iran.
    Lin, Chia-Feng
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Träteknik.
    Mohanty, Amar
    School of Engineering, University of Guelph, Albert A. Thornbrough Building, 80 South Ring Road East, ON N1G 2W1, Guelph, Canada.
    Misra, Manjusri
    School of Engineering, University of Guelph, Albert A. Thornbrough Building, 80 South Ring Road East, ON N1G 2W1, Guelph, Canada.
    Functionalised biochar in biocomposites: The effect of fire retardants, bioplastics and processing methods2023Inngår i: Composites Part C: Open Access, E-ISSN 2666-6820, Vol. 11, artikkel-id 100368Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Fire retardants, although can impart fire-safety in polymeric composites, are detrimental to the mechanical properties. Biochar can be used, in conjunction with fire retardants, to create a balance between fire-safety and mechanical performance. It is possible to thermally dope fire retardants into the pores of biochar to make it functionalised. Thus, the current work is intended in identifying a composite having the combination of the most desirable fire retardant, bioplastic, and a suitable processing method. A comparison was made between two fire retardants (lanosol and ammonium polyphosphate), bioplastics (wheat gluten and polyamide 11), and composite processing methods (compression and injection moulding). It was found that wheat gluten containing ammonium polyphosphate-doped biochar made by compression moulding had the best fire-safety properties with the lowest peak heat release rate (186 kW/m2), the highest fire performance index (0.6 m2s/kW), and the lowest fire growth index (1.6 kW/ms) with acceptable mechanical properties compared to the corresponding neat bioplastic. Thus, for gluten-based polymers, the use of ammonium polyphosphate thermally doped into biochar processed by compression moulding is recommended to both simultaneously improve fire-safety and conserve the mechanical strength of the resulting biocomposites.

    Fulltekst (pdf)
    fulltext
  • 4.
    Gao, Zihe
    et al.
    School of Civil Engineering, Zhengzhou University, Zhengzhou, Henan, China.
    Cai, Jiajun
    School of Civil Engineering, Zhengzhou University, Zhengzhou, Henan, China.
    Jiang, Lin
    Department of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing, China.
    Mensah, Rhoda Afriyie
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Fan, Chuangang
    School of Civil Engineering, Central South University, Changsha, Hunan, China.
    Investigation on the natural smoke exhaust performance by vertical shaft in tunnel fires under different ambient pressures2024Inngår i: Indoor + Built Environment, ISSN 1420-326X, E-ISSN 1423-0070Artikkel i tidsskrift (Fagfellevurdert)
  • 5.
    Gawusu, Sidique
    et al.
    Whiting School of Engineering, Johns Hopkins University, Baltimore, MD 21211, USA.
    Jamatutu, Seidu Abdulai
    School of Economics and Management, Nanjing University of Science and Technology, Nanjing, China.
    Zhang, Xiaobing
    School of Energy and Power and Engineering, Nanjing University of Science and Technology, Nanjing, China.
    Moomin, Solahudeen Tando
    Global Development Institute, School of Environment, Education and Development, University of Manchester, Manchester, UK.
    Ahmed, Abubakari
    Department of Urban Design and Infrastructure Studies, Faculty of Planning and Land Management, SD Dombo University of Business and Integrated Development Studies, Bamahu-Wa, Ghana.
    Mensah, Rhoda Afriyie
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Das, Oisik
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Ackah, Ishmael
    Department of Economics, School of Liberal Arts and Social Science, Ghana Institute of Management and Public Administration, Accra, Ghana.
    Spatial analysis and predictive modeling of energy poverty: insights for policy implementation2024Inngår i: Environment, Development and Sustainability, ISSN 1387-585X, E-ISSN 1573-2975Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Understanding and alleviating energy poverty is critical for sustainable development. This study harnesses a suite of Machine Learning (ML) algorithms to predict Multidimensional Energy Poverty Index (MEPI) and to highlight the spatial distribution of energy poverty. We assess the predictive accuracy of Random Forest (RF), Support Vector Machine (SVM), Artificial Neural Network (ANN), Multiple Linear Regression (MLR), and XGBoost models. The RF model outperforms others, achieving an R2 value of 0.92 and a Pearson Correlation Coefficient (PCC) of 0.97 on the testing dataset, indicative of a highly accurate prediction capability. XGBoost also demonstrates strong predictive power with corresponding values of 0.88 and 0.94, respectively. Our spatial analysis, revealing significant clustering of energy poverty with a Global Moran’s I value of 150.39, indicates that energy poverty is not only geographically concentrated but also intricately linked to socio-economic factors such as income levels, access to education, and nutritional status. These insights underscore the necessity of region-specific and socio-economically informed policy interventions. The results inform targeted interventions, particularly highlighting the critical roles of education and nutrition in mitigating energy poverty. The RF model’s accuracy rate of 92% on the testing set suggests that improvements in these sectors could significantly influence MEPI scores. The integration of ML and spatial analysis offers a nuanced and actionable understanding of energy poverty, paving the way for targeted, evidence-based policy formulation aimed at achieving SDG7: ensuring access to affordable, reliable, sustainable, and modern energy for all.

  • 6.
    Gawusu, Sidique
    et al.
    School of Energy and Power Engineering, Nanjing University of Science & Technology, Nanjing, China.
    Mensah, Rhoda Afriyie
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Das, Oisik
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Exploring distributed energy generation for sustainable development: A data mining approach2022Inngår i: Journal of Energy Storage, ISSN 2352-152X, E-ISSN 2352-1538, Vol. 48, artikkel-id 104018Artikkel, forskningsoversikt (Fagfellevurdert)
    Abstract [en]

    This study explores how data mining may be used to uncover patterns and trends in the area of distributed generation (DG). It employs the usage of the bibliometric approach. Bibliometric analysis is an increasingly common and rigorous approach for analysing huge datasets in the scientific community. It explains the evolution of a given discipline while highlighting new developments in the sector. To this purpose, this research examines the link between publishing patterns and the underlying technology trends and advances that influence these trends. Also included are key advances in the most recent findings in DG's research. The review finds that past research on system performance and optimization has built a solid conceptual framework for this research domain. The incorporation of new technologies, and the consideration of sustainability issues, are additional areas of concern. The overall strategy and methodologies utilized in this study may be applied to a wide range of research disciplines. Researchers will benefit from this study as a guide for future studies on DG integrating concerns.

  • 7.
    Gawusu, Sidique
    et al.
    Whiting School of Engineering, Johns Hopkins University, Baltimore, MD 21211, United States.
    Tando, Moomin Solahudeen
    Global Development Institute, School of Environment, Education and Development, The University of Manchester, United Kingdom.
    Ahmed, Abubakari
    Department of Urban Design and Infrastructure Studies, Faculty of Planning and Land Management, SD Dombo, University of Business and Integrated Development Studies, Bamahu-Wa, Ghana.
    Jamatutu, Seidu Abdulai
    School of Economics and Management, Nanjing University of Science and Technology, Nanjing, China.
    Mensah, Rhoda Afriyie
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Das, Oisik
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Mohammed, Abdul-Latif
    Department of Management, Newcastle Business School, The University of Newcastle, Australia.
    Yakubu, Ibrahim Nandom
    Department of Business and Education, School of Business, University for Development Studies, Tamale, Ghana.
    Ackah, Ishmael
    Department of Economics, School of Liberal Arts and Social Science, Ghana Institute of Management and Public Administration, Accra, Ghana.
    Decentralized energy systems and blockchain technology: Implications for alleviating energy poverty2024Inngår i: Sustainable Energy Technologies and Assessments, ISSN 2213-1388, E-ISSN 2213-1396, Vol. 65, artikkel-id 103795Artikkel, forskningsoversikt (Fagfellevurdert)
  • 8.
    Lin, Chia-Feng
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Träteknik.
    Karlsson, Olov
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Träteknik.
    Das, Oisik
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Mensah, Rhoda Afriyie
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Mantanis, George I.
    Laboratory of Wood Science and Technology, Department of Forestry, Wood Sciences and Design, University of Thessaly, GR-431 00 Karditsa, Greece.
    Jones, Dennis
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Träteknik. Department of Wood Processing and Biomaterials, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Praha 6-Suchdol, CZ-16521 Prague, Czech Republic.
    Antzutkin, Oleg N.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Kemiteknik.
    Försth, Michael
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Sandberg, Dick
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Träteknik. Department of Wood Processing and Biomaterials, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Praha 6-Suchdol, CZ-16521 Prague, Czech Republic.
    High Leach-Resistant Fire-Retardant Modified Pine Wood (Pinus sylvestris L.) by In Situ Phosphorylation and Carbamylation2023Inngår i: ACS Omega, E-ISSN 2470-1343, Vol. 8, nr 12, s. 11381-11396Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The exterior application of fire-retardant (FR) timber necessitates it to have high durability because of the possibility to be exposed to rainfall. In this study, water-leaching resistance of FR wood has been imparted by grafting phosphate and carbamate groups of the water-soluble FR additives ammonium dihydrogen phosphate (ADP)/urea onto the hydroxyl groups of wood polymers via vacuum-pressure impregnation, followed by drying/heating in hot air. A darker and more reddish wood surface was observed after the modification. Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, solid-state 13C cross-polarization magic-angle-spinning nuclear magnetic resonance (13C CP-MAS NMR), and direct-excitation 31P MAS NMR suggested the formation of C–O–P covalent bonds and urethane chemical bridges. Scanning electron microscopy/energy-dispersive X-ray spectrometry suggested the diffusion of ADP/urea into the cell wall. The gas evolution analyzed by thermogravimetric analysis coupled with quadrupole mass spectrometry revealed a potential grafting reaction mechanism starting with the thermal decomposition of urea. Thermal behavior showed that the FR-modified wood lowered the main decomposition temperature and promoted the formation of char residues at elevated temperatures. The FR activity was preserved even after an extensive water-leaching test, confirmed by the limiting oxygen index (LOI) and cone calorimetry. The reduction of fire hazards was achieved through the increase of the LOI to above 80%, reduction of 30% of the peak heat release rate (pHRR2), reduction of smoke production, and a longer ignition time. The modulus of elasticity of FR-modified wood increased by 40% without significantly decreasing the modulus of rupture.

    Fulltekst (pdf)
    fulltext
  • 9.
    Lin, Chia-Feng
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Träteknik.
    Karlsson, Olov
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Träteknik.
    Kim, Injeong
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Träteknik.
    Myronycheva, Olena
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Träteknik.
    Mensah, Rhoda Afriyie
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Försth, Michael
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Das, Oisik
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Mantanis, George I.
    Laboratory of Wood Science and Technology, Faculty of Forestry, Wood Sciences and Design, University of Thessaly, GR-431 00 Karditsa, Greece.
    Jones, Dennis
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Träteknik. Department of Wood Processing and Biomaterials, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Praha 6-Suchdol, CZ-16521 Prague, Czech Republic.
    Sandberg, Dick
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Träteknik. Department of Wood Processing and Biomaterials, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Praha 6-Suchdol, CZ-16521 Prague, Czech Republic.
    Fire Retardancy and Leaching Resistance of Furfurylated Pine Wood (Pinus sylvestris L.) Treated with Guanyl-Urea Phosphate2022Inngår i: Polymers, E-ISSN 2073-4360, Vol. 14, nr 9, artikkel-id 1829Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Guanyl-urea phosphate (GUP) was introduced into furfurylated wood in order to improve fire retardancy. Modified wood was produced via vacuum-pressure impregnation of the GUP–furfuryl alcohol (FA) aqueous solution, which was then polymerized at elevated temperature. The water leaching resistance of the treated wood was tested according to European standard EN 84, while the leached water was analyzed using ultra-performance liquid chromatography (UPLC) and inductively coupled plasma–sector field mass spectrometry (ICP-SFMS). This new type of furfurylated wood was further characterized in the laboratory by evaluating its morphology and elemental composition using optical microscopy and electron microscopy coupled with energy-dispersive X-ray spectrometry (SEM-EDX). The chemical functionality was detected using infrared spectroscopy (FTIR), and the fire resistance was tested using cone calorimetry. The dimensional stability was evaluated in wet–dry soaking cycle tests, along with the mechanical properties, such as the Brinell hardness and bending strength. The fire retardancy of the modified furfurylated wood indicated that the flammability of wood can be depressed to some extent by introducing GUP. This was reflected in an observed reduction in heat release rate (HRR2) from 454.8 to 264.9 kW/m2, without a reduction in the material properties. In addition, this leaching-resistant furfurylated wood exhibited higher fire retardancy compared to conventional furfurylated wood. A potential method for producing fire-retardant treated furfurylated wood stable to water exposure has been suggested.

    Fulltekst (pdf)
    fulltext
  • 10.
    Liu, Dongyun
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Wang, Chao
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Gonzalez, Jaime
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Mensah, Rhoda Afriyie
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Försth, Michael
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Das, Oisik
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Sas, Gabriel
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Elfgren, Lennart
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Tu, Yongming
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand. School of Civil Engineering, Southeast University, Nanjing, 211189, China.
    Correlation between early- and later-age performance indices of early frost-damaged concrete2022Inngår i: IABSE Symposium Prague 2022: Challenges for Existing and Oncoming Structures - Report, International Association for Bridge and Structural Engineering / [ed] František Wald, Pavel Ryjáček, International Association for Bridge and Structural Engineering, 2022, s. 934-941Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Freeze‐thaw cycles can lead to serious damage of early‐age concrete and influence its behaviour at later ages. In this study, the later‐age compressive strength, resistance to chloride penetration and resistance to freeze‐thaw of early frost‐damaged concrete were experimentally studied and the relationship between its early‐ (i.e., strength and resistivity) and later‐age (i.e., strength, chloride ion electric flux and freeze‐thaw durability factor) performance indices were analysed. Results show that the later‐age performance of the concrete subjected to freeze‐thaw cycles at early age was generally worse than that of the control samples, which had not undergone early frost damage. This was especially significant for the concrete subjected to freeze‐thaw cycles before the age of 24 h. The compressive strength after early frost action had a higher linear correlation with the later‐age indices of the concrete than the compressive strength before early frost action. Results also showed that the early‐age resistivity is a good indicator for the later‐age performance of early frost‐damaged concrete if the pre‐curing time before frosting is at least 24 h. 

  • 11.
    Liu, Hao
    et al.
    School of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing, 210094, China.
    Li, Mi
    School of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing, 210094, China.
    Zhao, Shuna
    School of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing, 210094, China.
    Mensah, Rhoda Afriyie
    School of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing, 210094, China.
    Das, Oisik
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Jiang, Lin
    School of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing, 210094, China.
    Xu, Qiang
    School of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing, 210094, China.
    Insights into wood species and aging effects on pyrolysis characteristics and combustion model by multi kinetics methods and model constructions2023Inngår i: Renewable energy, ISSN 0960-1481, E-ISSN 1879-0682, Vol. 206, s. 784-794Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Considering the extensive application of wood materials in the construction and manufacturing, waste wood has potential of converting into new natural energy sources. In this study, cypress, pine and fir woods commonly used in China, as well as old samples for above each species (more than 200 years old) have been used to study the aging and species effects on their thermal stability and combustion models. To obtain the kinetic triplets of the pyrolysis process, all samples have been heated in a nitrogen atmosphere with heating rates of 5, 10, 15, and 20 K min−1. The kinetics parameters of pyrolysis throughout the conversion process were then calculated using isoconversional method, Coats-Redfern (CR), and masterplots methods. The reconstructed theoretical models have been then adjusted using the accommodation functions. The results of this study contribute to an increased understanding of the fire mechanism of waste woods, and implications concerning to provide scientific theoretical guidance for its feasibility as a new energy fuel more efficiently.

  • 12.
    Mensah, Rhoda Afriyie
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Edström, David Aronsson
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Lundberg, Oskar
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Shanmugam, Vigneshwaran
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Jiang, Lin
    School of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing, 210094, China.
    Qiang, Xu
    School of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing, 210094, China.
    Försth, Michael
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Sas, Gabriel
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Hedenqvist, Mikael
    Department of Fibre and Polymer Technology, Polymeric Materials Division, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, Stockholm, 100 44, Sweden.
    Das, Oisik
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    The effect of infill density on the fire properties of polylactic acid 3D printed parts: A short communication2022Inngår i: Polymer testing, ISSN 0142-9418, E-ISSN 1873-2348, Vol. 111, artikkel-id 107594Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The use of 3D printing technology for manufacturing construction materials is gaining popularity, however, only a few studies have reported the fire behavior of such parts. In this research, the fire properties of 3D printed polylactide acid (PLA) parts with varying infill densities along with the tensile properties were analysed. The results from the fire tests showed that increasing the infill density increased the fuel load, which sustained combustion. Hence, the peak heat release rate and total heat release increased with an increment in infill density percentage. It was also observed that the increasing infill density had no effect on the flammability rating of the parts due to the constant shell thickness used for all the parts. In addition, the tensile strength and ductility of the parts increased with density as a porous part is more susceptible to failure than a solid homogeneous part.

  • 13.
    Mensah, Rhoda Afriyie
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Shanmugam, Vigneshwaran
    Department of Mechanical Engineering, Saveetha School of Engineering, Saveetha Institute of Medical and Technical Sciences, Chennai 602105, Tamil Nadu, India.
    Narayanan, Sreenivasan
    Department of Mechanical Engineering, Adishankara Institute of Engineering and Technology, Kalady Kerala 683574, India.
    Razavi, Seyed Mohammad Javad
    Department of Mechanical and Industrial Engineering, Norwegian University of Science and Technology (NTNU), 7491 Trondheim, Norway.
    Ulfberg, Adrian
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Blanksvärd, Thomas
    Skanska Sweden, Warfvinges Väg 25, 11274 Stockholm, Sweden.
    Sayahi, Faez
    Luossavaara-Kiirunavaara Aktiebolag (LKAB), 97437 Luleå, Sweden.
    Simonsson, Peter
    Industriellt Anläggningsbyggande, Broar och Byggnadsverk, LCC, 97187 Luleå, Sweden.
    Reinke, Benjamin
    NovoCarbo GmbH, 56281 Dörth, Germany.
    Försth, Michael
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Sas, Gabriel
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Sas, Daria
    Luleå tekniska universitet, Institutionen för ekonomi, teknik, konst och samhälle, Industriell ekonomi.
    Das, Oisik
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Biochar-Added Cementitious Materials—A Review on Mechanical, Thermal, and Environmental Properties2021Inngår i: Sustainability, E-ISSN 2071-1050, Vol. 13, nr 16, artikkel-id 9336Artikkel, forskningsoversikt (Fagfellevurdert)
    Abstract [en]

    The enhanced carbon footprint of the construction sector has created the need for CO2 emission control and mitigation. CO2 emissions in the construction sector are influenced by a variety of factors, including raw material preparation, cement production, and, most notably, the construction process. Thus, using biobased constituents in cement could reduce CO2 emissions. However, biobased constituents can degrade and have a negative impact on cement performance. Recently, carbonised biomass known as biochar has been found to be an effective partial replacement for cement. Various studies have reported improved mechanical strength and thermal properties with the inclusion of biochar in concrete. To comprehend the properties of biochar-added cementitious materials, the properties of biochar and their effect on concrete need to be examined. This review provides a critical examination of the mechanical and thermal properties of biochar and biochar-added cementitious materials. The study also covers biochar’s life cycle assessment and economic benefits. Overall, the purpose of this review article is to provide a means for researchers in the relevant field to gain a deeper understanding of the innate properties of biochar imparted into biochar-added cementitious materials for property enhancement and reduction of CO2 emissions.

  • 14.
    Mensah, Rhoda Afriyie
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Shanmugam, Vigneshwaran
    Department of Mechanical Engineering, Saveetha School of Engineering, Saveetha Institute of Medical and Technical Sciences, Chennai, 602105, Tamil Nadu, India.
    Narayanan, Sreenivasan
    Department of Mechanical Engineering, Adishankara Institute of Engineering and Technology, Kalady, Kerala, 683574, India.
    Renner, Juliana Sally
    School of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing, 210094, China.
    Babu, Karthik
    Department of Mechanical Engineering, Assam Energy Institute Sivasagar, A Center of Rajiv Gandhi Institute of Petroleum Technology, Assam, India.
    Neisiany, Rasoul Esmaeely
    Department of Materials and Polymer Engineering, Faculty of Engineering, Hakim Sabzevari University, Sabzevar, 9617976487, Iran.
    Försth, Michael
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Sas, Gabriel
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Das, Oisik
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    A review of sustainable and environment-friendly flame retardants used in plastics2022Inngår i: Polymer testing, ISSN 0142-9418, E-ISSN 1873-2348, Vol. 108, artikkel-id 107511Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The progressive transition from conventional structural designs to lightweight and more complex structures has led to the increase in the quantity of plastic materials in buildings. However, plastics have a major flaw: their low fire performance characterised by shorter ignition times and higher heat release rates. This has necessitated the incorporation of flame retardants (FRs) in plastics. Nevertheless, not all FRs are environmentally safe, hence, there is an urgent need for the development of sustainable biobased FRs that reduce environmental footprints while simultaneously improving the fire performance of plastics. This article addresses the negative connotation of FRs and reviews the most extensively used biobased FRs in plastics, their preparation (synthesis) and mode of application, performance evaluation as well as the leaching of FRs, and environmental fate. Some interesting observations in the review are the reduction of ignition times of plastics by the addition of FRs due to the rapid volatilisation of samples. In addition, the leaching rate of FRs is found to be higher in finer particles (micro and nanoparticles) compared to larger-sized ones and has the potential to dissolve in humic matter hence endangering the lives of humans and animals.

  • 15.
    Mensah, Rhoda Afriyie
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Vennström, Alva
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Shanmugam, Vigneshwaran
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Försth, Michael
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Li, Zhiwei
    National & Local Joint Engineering Research Center for Applied Technology of Hybrid Nanomaterials, Henan University, China.
    Restas, Agoston
    Department of Fire Protection and Rescue Control, National University of Public Service, Budapest, 1011, Hungary.
    Neisiany, Rasoul Esmaeely
    Department of Materials and Polymer Engineering, Faculty of Engineering, Hakim Sabzevari University, Sabzevar, 9617976487, Iran.
    Sokol, Denis
    Department of Inorganic Chemistry, Vilnius University, Naugarduko 24, Vilnius, LT-03225, Lithuania.
    Misra, Manjusri
    School of Engineering, University of Guelph, Albert A. Thornbrough Building, 80 South Ring Road East, Guelph, ON N1G 2W1, Canada.
    Mohanty, Amar
    School of Engineering, University of Guelph, Albert A. Thornbrough Building, 80 South Ring Road East, Guelph, ON N1G 2W1, Canada.
    Hedenqvist, Mikael
    Department of Fibre and Polymer Technology, Polymeric Materials Division, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, Stockholm, 100 44, Sweden.
    Das, Oisik
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Influence of biochar and flame retardant on mechanical, thermal, and flammability properties of wheat gluten composites2022Inngår i: Composites Part C: Open Access, ISSN 2666-6820, Vol. 9, artikkel-id 100332Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The use of environmentally friendly materials such as bio-sourced plastics is being driven by increased awareness of environmental issues caused by synthetic plastics. However, bio-sourced plastics have poor fire behaviour that limits their application. The addition of a flame retardant to these plastics is one effective way to increase the fire resistance property; however, the flame retardant should not interfere with the mechanical performance of the plastic. Most flame retardants act as stress concentration points, reducing tensile strength. Hence, to create a balance between tensile strength and fire resistance, biochar (to conserve strength) and lanosol (to improve fire resistance) were added to wheat gluten bioplastic in various ratios and the optimal ratio was identified. Wheat gluten composites were fabricated using compression moulding at four different concentrations of lanosol (2, 4, 6, and 8 wt.%) and biochar (2, 4, 6, and 8 wt.%). From the test results, the composite with 4 wt.% lanosol and 6 wt.% biochar exhibited a good balance between the mechanical and fire properties; it conserved the strength and improved the fire properties (39 % reduction in peak heat release rate).

  • 16.
    Mensah, Rhoda Afriyie
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Wang, Dong
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Shanmugam, Vigneshwaran
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Sas, Gabriel
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Försth, Michael
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Das, Oisik
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Fire behaviour of biochar-based cementitious composites2024Inngår i: Composites Part C: Open Access, ISSN 2666-6820, Vol. 14, artikkel-id 100471Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The study aimed to test the hypothesis that biochar's unique properties, such as its microporous structure, can enhance concrete's resilience to high temperatures. Despite expectations of reduced crack formation and enhanced fire resistance, the experimental results revealed a limited impact on concrete's fire behaviour. The investigation involved the use of two biochar types, fine and coarse biochar as replacements for cement and aggregates, respectively. Fine biochar exhibited higher water absorption and Young's modulus than coarse biochar, but both resisted ignition at 35 kW/m2 radiative heat flux and had peak heat release rates below 40 kW/m2. Incorporating these biochars at varying weight percentages (10, 15, and 20 wt.%) into concrete led to a gradual decline in compressive and tensile strength due to reduced binding ability with increased biochar content. Exposure to 1000 °C compromised mechanical properties across all the samples. However, the biochar concrete maintained compressive strength (compared to the control) with up to 20 wt.% biochar as a fine aggregate substitute after exposure to 600 °C, and as a cement replacement after exposure to 200 °C. This substitution also yielded a significant reduction in CO2 emissions (50 % reduction as the biochar loading amount doubled) from concrete manufacturing, showcasing biochar's potential for sustainable construction practices. Despite not fully supporting the initial hypothesis, the study demonstrated biochar's viability in reducing carbon footprint while maintaining concrete strength under certain fire conditions.

    Fulltekst (pdf)
    fulltext
  • 17.
    Paladugu, Sri Ram Murthy
    et al.
    VIT AP Univ, Sch Mech Engn, Amaravati 522337, India.
    Sreekanth, P. S. Rama
    VIT AP Univ, Sch Mech Engn, Amaravati 522337, India.
    Sahu, Santosh Kumar
    VIT AP Univ, Sch Mech Engn, Amaravati 522337, India.
    Naresh, K.
    Univ Southern Calif, Dept Chem Engn & Mat Sci, Los Angeles, CA 90089 USA.
    Karthick, S. Arun
    Sri Sivasubramaniya Nadar Coll Engn, Dept Biomed Engn, Feynman Nano Lab, Chennai 603110, India.
    Venkateshwaran, N.
    Rajalakshmi Engn Coll, Dept Mech Engn, Chennai 600125, India.
    Ramoni, Monsuru
    Navajo Tech Univ, Sch Engn Math & Technol, Crownpoint, NM 87313 USA.
    Mensah, Rhoda Afriyie
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Das, Oisik
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Shanmugam, Ragavanantham
    Navajo Tech Univ, Sch Engn Math & Technol, Crownpoint, NM 87313 USA.
    A Comprehensive Review of Self-Healing Polymer, Metal, and Ceramic Matrix Composites and Their Modeling Aspects for Aerospace Applications2022Inngår i: Materials, ISSN 1996-1944, E-ISSN 1996-1944, Vol. 15, nr 23, artikkel-id 8521Artikkel, forskningsoversikt (Fagfellevurdert)
    Abstract [en]

    Composites can be divided into three groups based on their matrix materials, namely polymer, metal and ceramic. Composite materials fail due to micro cracks. Repairing is complex and almost impossible if cracks appear on the surface and interior, which minimizes reliability and material life. In order to save the material from failure and prolong its lifetime without compromising mechanical properties, self-healing is one of the emerging and best techniques. The studies to address the advantages and challenges of self-healing properties of different matrix materials are very limited; however, this review addresses all three different groups of composites. Self-healing composites are fabricated to heal cracks, prevent any obstructed failure, and improve the lifetime of structures. They can self-diagnose their structure after being affected by external forces and repair damages and cracks to a certain degree. This review aims to provide information on the recent developments and prospects of self-healing composites and their applications in various fields such as aerospace, automobiles etc. Fabrication and characterization techniques as well as intrinsic and extrinsic self-healing techniques are discussed based on the latest achievements, including microcapsule embedment, fibers embedment, and vascular networks self-healing.

    Fulltekst (pdf)
    fulltext
  • 18.
    Panahi, Parisa
    et al.
    Department of Chemical Engineering, Isfahan University of Technology, Isfahan 84156-83111, Iran.
    Khorasani, Saied Nouri
    Department of Chemical Engineering, Isfahan University of Technology, Isfahan 84156-83111, Iran.
    Mensah, Rhoda Afriyie
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Das, Oisik
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Neisiany, Rasoul Esmaeely
    Department of Polymer Engineering, Hakim Sabzevari University, Sabzevar 9617976487, Iran; Biotechnology Centre, Silesian University of Technology, Krzywoustego 8, 44-100 Gliwice, Poland.
    A review of the characterization methods for self-healing assessment in polymeric coatings2024Inngår i: Progress in organic coatings, ISSN 0300-9440, E-ISSN 1873-331X, Vol. 186, artikkel-id 108055Artikkel, forskningsoversikt (Fagfellevurdert)
  • 19.
    Perroud, Théo
    et al.
    Department of Fibre and Polymer Technology, Polymeric Materials Division, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, Stockholm 100 44, Sweden.
    Shanmugam, Vigneshwaran
    Department of Mechanical Engineering, Saveetha School of Engineering, Saveetha Institute of Medical and Technical Sciences, Chennai, 602105, India.
    Mensah, Rhoda Afriyie
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Jiang, Lin
    School of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing, 210094, China.
    Xu, Qiang
    School of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing, 210094, China.
    Neisiany, Rasoul Esmaeely
    Department of Materials and Polymer Engineering, Faculty of Engineering, Hakim Sabzevari University, Sabzevar, 9617976487, Iran.
    Sas, Gabriel
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Försth, Michael
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Kim, Nam Kyeun
    Centre for Advanced Composite Materials, Mechanical Engineering Department, University of Auckland, 1142, New Zealand.
    Hedenqvist, Mikael S.
    Department of Fibre and Polymer Technology, Polymeric Materials Division, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, Stockholm 100 44, Sweden.
    Das, Oisik
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Testing bioplastic containing functionalised biochar2022Inngår i: Polymer testing, ISSN 0142-9418, E-ISSN 1873-2348, Vol. 113, artikkel-id 107657Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Although flame retardants are very effective in reducing the fire hazard of polymeric materials, their presence may be detrimental to mechanical strength. Hence, in order to have a holistic improvement of performance properties, a new approach has been developed wherein biochar is used to host a naturally-occurring flame retardant (lanosol). The issue of loss in mechanical strength of a polymer host is alleviated by the use of biochar. Three different doping procedures were investigated, namely, dry mixing, and chemical and thermal-based doping, to integrate lanosol into the biochar pores. The doped biochar was used to develop wheat gluten-based blends. The mechanical and flammability properties of the blends were assessed. It was found that thermal doping was the most effective in introducing significant amounts of lanosol particles inside the biochar pores. The bioplastic containing chemically, and thermally doped biochar had equal tensile strength (5.2 MPa), which was comparable to that of the unmodified material (5.4 MPa). The thermally doped biochar displayed the lowest cone calorimeter peak heat release rate (636 kW m−2) for combustion and the highest apparent activation energy (32.4 kJ mol−1) for decomposition. Thus, for flame retarding protein-based matrices, the use of additives thermally doped into biochar is recommended to both simultaneously improve fire-resistance and conserve mechanical strength.

  • 20.
    Raja, Pradeep
    et al.
    Department of Mechanical Engineering, National Institute of Technology, Tiruchirappalli, Tamil Nadu, 620015, India.
    Murugan, Vignesh
    Department of Civil Engineering, Oriental University, Indore, Madhya Pradesh, 453555, India.
    Ravichandran, Sindhu
    Department of Civil Engineering, Karpagam Academy of Higher Education, Salem – Kochi Hwy, Eachanari, Tamil Nadu, 641021, India.
    Behera, Laxmidhar
    Department of Civil Engineering, Centurion University of Technology and Management, Odisha, 761211, India.
    Mensah, Rhoda Afriyie
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Mani, Satthiyaraju
    Department of Mechanical Engineering, Kathir College of Engineering, Neelambur, Coimbatore, Tamil Nadu, 641062, India.
    Kasi, AnanthaKumar
    Department of Mechanical Engineering, Karpagam College of Engineering, Coimbatore, Tamil Nadu, 641032, India.
    Balasubramanian, Karthik Babu Nilagiri
    Department of Mechanical Engineering, Assam Energy Institute, A Centre of RGIPT, Sivasagar, Assam, 785640, India.
    Sas, Gabriel
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Vahabi, Henri
    University of Lorraine, Centrale Supélec, Laboratoire MOPS E.A. 4423, Metz, F-57070, France.
    Das, Oisik
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    A Review of Sustainable Bio-Based Insulation Materials for Energy-Efficient Buildings2023Inngår i: Macromolecular materials and engineering, ISSN 1438-7492, E-ISSN 1439-2054, Vol. 308, nr 10, artikkel-id 2300086Artikkel, forskningsoversikt (Fagfellevurdert)
    Abstract [en]

    The surge towards a sustainable future in the construction industry requires the use of bio-based insulation materials as an alternative to conventional ones for improving energy efficiency in structures. In this article, the features of bio-based insulation materials, including their thermal conductivities, moisture buffering value, fire performance, and life cycle evaluations are examined. It is clear from the review that pre- and post-treatment of the bio-based materials used for insulation materials optimize their properties. The life cycle analysis reveals a significant reduction in global warming potential (GWP) compared to conventional foams. In addition, it is envisaged that producing bio-based insulation materials on a larger scale will further decrease the net GWP. The article, therefore, proposes the implementation of policies that will promote the commercialization of bio-based insulation materials.

    Fulltekst (pdf)
    fulltext
  • 21.
    Renner, Juliana Sally
    et al.
    School of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing 210094, China.
    Mensah, Rhoda Afriyie
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Jiang, Lin
    School of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing 210094, China.
    Xu, Qiang
    School of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing 210094, China.
    Das, Oisik
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Berto, Filippo
    Department of Mechanical and Industrial Engineering, Norwegian University of Science and Technology (NTNU), 7491 Trondheim, Norway.
    Fire behavior of wood-based composite materials2021Inngår i: Polymers, E-ISSN 2073-4360, Vol. 13, nr 24, artikkel-id 4352Artikkel, forskningsoversikt (Fagfellevurdert)
    Abstract [en]

    Wood-based composites such as wood plastic composites (WPC) are emerging as a sustainable and excellent performance materials consisting of wood reinforced with polymer matrix with a variety of applications in construction industries. In this context, wood-based composite materials used in construction industries have witnessed a vigorous growth, leading to a great production activity. However, the main setbacks are their high flammability during fires. To address this issue, flame retardants are utilized to improve the performance of fire properties as well as the flame retardancy of WPC material. In this review, flame retardants employed during manufacturing process with their mechanical properties designed to achieve an enhanced flame retardancy were examined. The addition of flame retardants and manufacturing techniques applied were found to be an optimum condition to improve fire resistance and mechanical properties. The review focuses on the manufacturing techniques, applications, mechanical properties and flammability studies of wood fiber/flour polymer/plastics composites materials. Various flame retardant of WPCs and summary of future prospects were also highlighted.

  • 22.
    Rodrigues, Quentin
    et al.
    Université Clermont Auvergne, Clermont Auvergne INP, Institut Pascal, F-63000 Clermont-Ferrand, France.
    Huber, Johannes Albert Josef
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Träteknik.
    Hansson, Lars
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Träteknik.
    Mensah, Rhoda Afriyie
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Moutou Pitti, Rostand
    IRT, Libreville, Gabon.
    Using X-Ray Computed Tomography To Measure Fire Degradation Of A Timber Connection2023Inngår i: World Conference on Timber Engineering (WCTE 2023): Timber for a Livable Future / [ed] Nyrud, A. Q.; Malo, K. A.; Nore, K., Oslo: World Conference on Timber Engineering 2023 (WCTE 2023) , 2023, s. 1519-1525Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The charring behaviour of timber elements under fire is well understood, however, the effects of fire and heat on connections are not equally well known. Timber connections often use steel fasteners, like screws or angle brackets, which conduct heat much better than wood. Moreover, these fasteners lose their mechanical resistance and capacity under elevated temperatures. X-ray computed tomography (CT) can be used to reconstruct the internal structure of wood non-destructively. It should therefore be possible to use this technology to also study the progressive degradation due to fire of a timber connection. The goal of the present study is to investigate how CT can be used to analyse the degradation of a timber connection due to fire. Samples of Norway spruce with self-tapping screws were scanned before and after a fire exposure, and mechanical tests were performed. The results indicate that the degradation due to fire in a timber connection can be observed in CT scans, but that certain measures need to be taken to minimise the effects of image artefacts due to X-ray scattering and photon starvation.

    Fulltekst (pdf)
    fulltext
  • 23.
    Sanned, Ellinor
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Mensah, Rhoda A.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Försth, Michael
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Das, Oisik
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Response to the comments made by Vytenis Babrauskas on “the curious case of the second/end peak in the heat release rate of wood: A cone calorimeter investigation”2023Inngår i: Fire and Materials, ISSN 0308-0501, E-ISSN 1099-1018, Vol. 47, nr 5, s. 735-735Artikkel i tidsskrift (Annet vitenskapelig)
    Fulltekst (pdf)
    fulltext
  • 24.
    Sanned, Ellinor
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Mensah, Rhoda Afriyie
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Försth, Michael
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Das, Oisik
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    The curious case of the second/end peak in the heat release rate of wood: A cone calorimeter investigation2023Inngår i: Fire and Materials, ISSN 0308-0501, E-ISSN 1099-1018, Vol. 47, nr 4, s. 498-513Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The reasons behind the occurrence of a second/end peak heat release rate (PHRR) during wood combustion under radiative heating were determined. Effects of the type of rear material, wood thickness, char progression, and its microstructure, as well as moisture content/transport in spruce wood, were studied. Rear materials used were insulating Kaowool, conducting steel, and the same wood but physically separated from test specimen by aluminium foil. The intensity of the second/end PHRR with Kaowool was almost 50% more than that of the sample with steel. Thus, the second/end peak is governed by the boundary condition defined by the rear material, which determines the heat losses at the rear side of the specimen and consequently the temperature of the specimen. Higher specimen temperature enhances the pyrolysis rate, thereby causing the second/end PHRR. The appearance times and values of the second/end PHRR for 30, 20, and 10 mm wood were 1740 s/78 kWm−2, 685 s/134 kWm−2, and 450 s/160 kWm−2, respectively. Char progressed to the rear of the samples even with a thin (8 mm) conductive steel substrate. Cracks in char grew almost three times wider during the second/end PHRR compared to the sample with no second/end peak. Char cracking had no significance on the time of occurrence of the second/end PHRR but affected the overall heat release. High moisture content reduced the charring rate and delayed the time of occurrence of the second/end PHRR as more water was needed to undergo a phase change, requiring a higher amount of energy.

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  • 25.
    Shankar, Adith Narayan
    et al.
    Materials Science and Engineering, Cornell University, Ithaca, New York 14853, USA.
    Netravali, Anil Narayan
    Human Centered Design, Cornell University, Ithaca, New York 14853, USA.
    Mensah, Rhoda Afriyie
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Das, Oisik
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Microscale combustion calorimetry assessment of green composites made with chicken feather-modified soy protein resins and jute fabric2023Inngår i: Composites Part C: Open Access, E-ISSN 2666-6820, Vol. 12, artikkel-id 100394Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Biodegradable, and sustainably produced, ‘green’ plastics are actively being researched to replace conventional, environmentally harmful petroleum-based plastics. However, before these green plastics get adopted, they must match the properties of their conventional counterparts. In many applications, fire-safety can be a key parameter where naturally derived green materials could potentially outcompete petroleum-based plastics. In the present research, green resins and composites were fabricated using soy protein isolate (SPI), waste chicken feather fibers (CFF), jute fabric (JF), and glutaraldehyde (GA), and evaluated for their critical fire-safety parameters through Microscale Cone Calorimetry (MCC) characterization. The loading of CFF from 0 to 30 wt% increased the specific peak heat release rate (pHRR) from 101 to 120 W/g for CFF/SPI resins without GA and from 94.5 to 114 W/g for GA crosslinked CFF/SPI resins. GA was thus shown to improve fire-safety for CFF/SPI resins. However, for JF/(CFF/SPI) composites, CFF did not show a proportional relationship with fire-safety. Rather, at 20 wt% CFF, the pHRR was minimized to 81.1 W/g for JF/(CFF/SPI) composites without GA and to 86.0 W/g for GA-crosslinked JF/(CFF/SPI) composites. This demonstrated that the addition of JF improved fire-safety despite its known combustibility, and even removed the need of the toxic crosslinker GA. Results also indicated that all variations of the fabricated CFF/SPI resins and JF/(CFF/SPI) composites had lower specific pHRR than typical petroleum-based plastics, clearly demonstrating the benefits of switching to SPI based green resins and composites. These green composites would be suitable for many applications including housing and transportation where fire-safety can be critical.

    Fulltekst (pdf)
    fulltext
  • 26.
    Shanmugam, Vigneshwaran
    et al.
    Department of Mechanical Engineering, Saveetha School of Engineering, Saveetha Institute of Medical and Technical Sciences, Chennai, Tamil Nadu 602105, India.
    Mensah, Rhoda Afriyie
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Babu, Karthik
    Department of Mechanical Engineering, Assam Energy Institute, Sivasagar, A Center of Rajiv Gandhi Institute of Petroleum Technology, Assam 785697, India.
    Gawusu, Sidique
    School of Energy and Power Engineering, Nanjing University of Science & Technology, Nanjing 210094, P. R. China.
    Chanda, Avishek
    Composite Materials and Engineering Center, Washington State University, 2001 East Grimes Way, Pullman, WA 99164, USA.
    Tu, Yongming
    School of Civil Engineering, Southeast University, Nanjing 211189, P. R. China; National Engineering Research Center for Prestressing Technology, Southeast University, Nanjing 211189, P. R. China.
    Neisiany, Rasoul Esmaeely
    Department of Materials and Polymer Engineering, Faculty of Engineering, Hakim Sabzevari University, Sabzevar 9617976487, Iran.
    Försth, Michael
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Sas, Gabriel
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Das, Oisik
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    A Review of the Synthesis, Properties, and Applications of 2D Materials2022Inngår i: Particle & particle systems characterization, ISSN 0934-0866, E-ISSN 1521-4117, Vol. 39, nr 6, artikkel-id 2200031Artikkel, forskningsoversikt (Fagfellevurdert)
    Abstract [en]

    In the modern age of nanotechnology, the discovery of graphene has opened up the way to study and develop of several novel 2D materials. The unique physical and chemical properties of 2D materials have enhanced their research, making them superior to the commercial bulk materials used in various applications. Efforts have been made in the current study to present an overview of the intrinsic properties of these materials. Furthermore, synthesis and applications are also reviewed and discussed. Finally, the future outlook of 2D materials is discussed to enhance the research and performance of these materials, which can result in broader applications benefitting the electrical and electronics industries and society. Intensive research into 2D materials is expected to lead to the discovery of new materials with enhanced properties that will benefit the industry and society at large.

  • 27.
    Shanmugam, Vigneshwaran
    et al.
    Department of Mechanical Engineering, Saveetha Institute of Medical and Technical Sciences, Chennai, Tamil Nadu, India.
    Mensah, Rhoda Afriyie
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Karthik Babu, N. B.
    Department of Mechanical Engineering, Assam Energy Institute, A Center of Rajiv Gandhi Institute of Petroleum Technology, Sivasagar, Assam, India.
    Pradeep Raja, C.
    Department of Mechanical Engineering, National Institute of Technology, Puducherry, India.
    Ronald Aseer, J.
    Department of Mechanical Engineering, National Institute of Technology, Puducherry, India.
    Pugazhenthi, A.
    Department of Mechanical Engineering, University College of Engineering, Dindigul, Tamil Nadu, India.
    Satish Kumar, D.
    Department of Mechanical Engineering, Saveetha Institute of Medical and Technical Sciences, Chennai, Tamil Nadu, India.
    Das, Oisik
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Introduction to lightweight materials2022Inngår i: Materials for Lightweight Constructions / [ed] S. Thirumalai Kumaran, Tae Jo Ko, S. Suresh Kumar, Temel Varol, CRC Press , 2022, 1, s. 1-15Kapittel i bok, del av antologi (Annet vitenskapelig)
  • 28.
    Shanmugam, Vigneshwaran
    et al.
    Department of Mechanical Engineering, Saveetha School of Engineering, Saveetha Institute of Medical and Technical Sciences, Chennai 602 105, Tamilnadu, India.
    Sreenivasan, S.N.
    Department of Mechanical Engineering, Adishankara Institute of Engineering and Technology, Kalady Kerala – 683574, India.
    Mensah, Rhoda Afriyie
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Försth, Michael
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Sas, Gabriel
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Hedenqvist, Mikael S
    Department of Fibre and Polymer Technology, Polymeric Materials Division, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, Stockholm 100 44, Sweden.
    Neisiany, Rasoul Esmaeely
    Department of Materials and Polymer Engineering, Faculty of Engineering, Hakim Sabzevari University, Sabzevar, 9617976487, Iran.
    Tu, Yongming
    Department of Mechanical and Industrial Engineering, Norwegian University of Science and Technology NTNU, S.P. Andersens Veg 3, Trondheim, 7031, Norway; School of Civil Engineering, Southeast University, Nanjing 211189, China.
    Das, Oisik
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    A Review on Combustion and Mechanical Behaviour of Pyrolysis Biochar2022Inngår i: Materials Today Communications, ISSN 2352-4928, Vol. 31, artikkel-id 103629Artikkel, forskningsoversikt (Fagfellevurdert)
    Abstract [en]

    Biochar has unique physical and chemical properties, making it a viable and sustainable future generation material for a variety of applications. The applications include power generation, composite production, construction (as a reinforcement), and soil amendment. The inherent good mechanical and combustion (or fire) resistance properties of biochar are attractive, however, there are limited reports, despite its effects on bulk material properties being well-documented. Comprehending these innate properties of biochar is critical for tailoring the mechanical and fire properties of biochar-based materials and structures. Therefore, an attempt has been made in this article to garner and analyse literatures reported on the mechanical and combustion properties of biochar without being integrated with a material or structural system (e.g. composite). Biochar produced at high pyrolysis temperatures (>500 ℃) showed high fire resistance property, because of the absence of the volatile matters and development of strong C-C covalent bonds. The mechanical and combustion properties of biocharcan be controlled by varying the biochar size, porus nature, and pyrolysis temperature. The information presented in this article is crucial and can be used as a guide to develop biochar-based materials and structures for mechanical and fire resistance applications.

  • 29.
    Vijaybabu, T. R.
    et al.
    Department of Mechanical Engineering, GMR Institute of Technology, Rajam, Andra Pradesh, 532127, India.
    Ramesh, T.
    Department of Mechanical Engineering, National Institute of Technology, Tiruchirappalli, Tamil Nadu, 620015, India.
    Pandipati, Suman
    Deparment of Mechanical Engineering, Aditya Institute of technology and management, Tekkali, Andhra Pradesh, 532203, India.
    Mishra, Sujit
    Department of Mechanical Engineering, Centurion University of Technology and Management, Paralakhemundi, Odisha, 761211, India.
    Sridevi, G.
    Department of Mechanical Engineering, Centurion University of Technology and Management, Paralakhemundi, Odisha, 761211, India.
    Raja, C Pradeep
    Department of Mechanical Engineering, National Institute of Technology, Tiruchirappalli, Tamil Nadu, 620015, India.
    Mensah, Rhoda Afriyie
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Das, Oisik
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Misra, Manjusri
    School of Engineering, University of Guelph, Albert A. Thornbrough Building, 80 South Ring Road East, Guelph, ON N1G 2W1, Canada.
    Mohanty, Amar
    School of Engineering, University of Guelph, Albert A. Thornbrough Building, 80 South Ring Road East, Guelph, ON N1G 2W1, Canada.
    Karthik Babu, N. B.
    Department of Mechanical Engineering, Assam Energy Institute, A centre of Rajiv Gandhi Institute of Petroleum Technology, Sivasagar, Assam, 785697, India.
    High Thermal Conductivity Polymer Composites Fabrication through Conventional and 3D Printing Processes: State-of-the-Art and Future Trends2023Inngår i: Macromolecular materials and engineering, ISSN 1438-7492, E-ISSN 1439-2054, Vol. 308, nr 7, artikkel-id 2300001Artikkel, forskningsoversikt (Fagfellevurdert)
    Abstract [en]

    The lifespan and the performance of flexible electronic devices and components are affected by the large accumulation of heat, and this problem must be addressed by thermally conductive polymer composite films. Therefore, the need for the development of high thermal conductivity nanocomposites has a strong role in various applications. In this article, the effect of different particle reinforcements such as single and hybrid form, coated and uncoated particles, and chemically treated particles on the thermal conductivity of various polymers are reviewed and the mechanism behind the improvement of the required properties are discussed. Furthermore, the role of manufacturing processes such as injection molding, compression molding, and 3D printing techniques in the production of high thermal conductivity polymer composites is detailed. Finally, the potential for future research is discussed, which can help researchers to work on the thermal properties enhancement for polymeric materials.

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    fulltext
  • 30.
    Wang, Dong
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand. Xiang Tan University College of Civil Engineering, Hunan Province, Yang Gu Tang Street, 411105, Xiang Tan, China.
    Luo, Baifu
    Xiang Tan University College of Civil Engineering, Hunan Province, Yang Gu Tang Street, 411105, Xiang Tan, China.
    Deng, Junjie
    Xiang Tan University College of Civil Engineering, Hunan Province, Yang Gu Tang Street, 411105, Xiang Tan, China.
    Feng, Qinqin
    Xiang Tan University College of Civil Engineering, Hunan Province, Yang Gu Tang Street, 411105, Xiang Tan, China.
    Zhang, Wei
    Xiang Tan University College of Civil Engineering, Hunan Province, Yang Gu Tang Street, 411105, Xiang Tan, China.
    Deng, Chengwei
    Xiang Tan University College of Civil Engineering, Hunan Province, Yang Gu Tang Street, 411105, Xiang Tan, China.
    Mensah, Rhoda Afriyie
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Restas, Agoston
    Institute of Disaster Management, Ludovika University of Public Service, Ludovika Tér 2, 1083, Budapest, Hungary.
    Racz, Sandor
    Institute of Disaster Management, Ludovika University of Public Service, Ludovika Tér 2, 1083, Budapest, Hungary.
    Rauscher, Judit
    Institute of Disaster Management, Ludovika University of Public Service, Ludovika Tér 2, 1083, Budapest, Hungary.
    Das, Oisik
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Optimized fire resistance of alkali-activated high-performance concrete by steel fiber2024Inngår i: Journal of thermal analysis and calorimetry (Print), ISSN 1388-6150, E-ISSN 1588-2926Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The behavior of alkali-activated ultra-high-performance concrete (A-UHPC) at elevated temperatures is unknown. This study addresses this gap by investigating the behavior of A-UHPC under varying temperatures with steel fiber additions (1%, 2%, and 3%), and considering target temperatures (20 °C, 200 °C, 400 °C, 600 °C, and 800 °C) as design variables. As the results, A-UHPC with steel fibers showed improved fire resistance, suffering less compressive strength loss at 800 °C than fiber-free A-UHPC. High temperatures initially optimized A-UHPC’s microstructure at 200 °C but later caused damage through microstructure propagation. Steel fibers enhanced A-UHPC’s ductility, resulting in ductile failure even at 800 °C. A-UHPC exhibited a unique mechanical degradation pattern under elevated temperatures, distinct from ordinary cement-based concrete. Empirical models accurately predicted its behavior, offering valuable insights for engineers dealing with heavy loads and high temperatures.

  • 31.
    Xu, Qiang
    et al.
    School of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing 210014, China.
    Jiang, Lin
    School of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing 210014, China.
    Majlingova, Andrea
    Faculty of Wood Science and Technology, Technical University in Zvolen, 96053 Zvolen, Slovakia.
    Ulbrikova, Nikoleta
    Faculty of Wood Science and Technology, Technical University in Zvolen, 96053 Zvolen, Slovakia.
    Mensah, Rhoda Afriyie
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Das, Oisik
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Berto, Filippo
    Department of Mechanical and Industrial Engineering, Norwegian University of Science and Technology (NTNU), NO-7491 Trondheim, Norway.
    Wood Dust Flammability Analysis by Microscale Combustion Calorimetry2022Inngår i: Polymers, E-ISSN 2073-4360, Vol. 14, nr 1, artikkel-id 45Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    To study the practicability of a micro combustion calorimeter to analyze the calorimetry kinetics of wood, a micro combustion calorimeter with 13 heating rates from 0.1 to 5.5 K/s was used to perform the analysis of 10 kinds of common hardwood and softwood samples. As a microscale combustion measurement method, MCC (microscale combustion calorimetry) can be used to judge the flammability of materials. However, there are two methods for measuring MCC: Method A and Method B. However, there is no uniform standard for the application of combustible MCC methods. In this study, the two MCC standard measurement Methods A and B were employed to check their practicability. With Method A, the maximum specific heat release rate, heat release temperature, and specific heat release of the samples were obtained at different heating rates, while for Method B, the maximum specific combustion rate, combustion temperature and net calorific values of the samples were obtained at different heating rates. The ignition capacity and heat release capacity were then derived and evaluated for all the common hardwood and softwood samples. The results obtained by the two methods have significant differences in the shape of the specific heat release rate curves and the amplitude of the characteristic parameters, which lead to the differences of the derived parameters. A comparison of the specific heat release and the net calorific heat of combustion with the gross caloric values and heating values obtained by bomb calorimetry was also made. The results show that Method B has the potentiality to evaluate the amount of combustion heat release of materials.

  • 32.
    Zhao, Shu-Na
    et al.
    School of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing 210094, Jiangsu, China.
    Han, Zhong-Xuan
    School of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing 210094, Jiangsu, China.
    Li, Mi
    School of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing 210094, Jiangsu, China.
    Liu, Hao
    School of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing 210094, Jiangsu, China.
    Mensah, Rhoda Afriyie
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Das, Oisik
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Jiang, Lin
    School of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing 210094, Jiangsu, China.
    Insights into thermochemistry, kinetics, and pyrolysis behavior of green gas generator 5- aminotetrazole by experiment and theoretical methods2023Inngår i: Case Studies in Thermal Engineering, ISSN 2214-157X, Vol. 49, artikkel-id 103217Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Green gas generator 5-aminotetrazole(5-AT) has been widely used as a kind of energetic material with excellent properties, and it is crucial to understand its pyrolysis process and mechanism. The present study comprehensively investigated the thermochemistry, kinetics, and pyrolysis mechanism of green gas generator 5-AT, using a combination of experimental analysis and theoretical calculation. Thermogravimetric analysis (TGA) and fourier transform infrared spectroscopy (FTIR) were used to investigate the pyrolysis behavior of 5AT and energy barriers of transition states for different pyrolysis paths of three isomers of 5AT were also calculated at a high and reliable level of theory CCSD(T)/cc-pvtz. The results showed that the pyrolysis of 5-AT had five reaction stages and kinetic parameters in each stage were determined by Kissinger method and Criado method. Furthermore, the elimination of N2 from the tetrazole ring occurred before that of HN3, and N2 elimination had lower energy than HN3 elimination for 1-hydrogen-5-aminotetrazole and 2-hydrogen-5-aminotetrazole, but HN3 elimination had lower energy for 5-iminotetrazole. The results of the study provide useful insights into the pyrolysis mechanism and kinetics of 5-AT and could contribute to its efficient utilization in various applications.

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    fulltext
  • 33.
    Öhrn, Olina
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Sykam, Kesavarao
    Polymers & Functional Materials Division, Indian Institute of Chemical Technology, Uppal Road, Tarnaka, Hyderabad, 500007, Telangana, India.
    Gawusu, Sidique
    Whiting School of Engineering, Johns Hopkins University, Baltimore, MD 21218, United States.
    Mensah, Rhoda Afriyie
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Försth, Michael
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Shanmugam, Vigneshwaran
    Department of Mechanical Engineering, Saveetha School of Engineering, Saveetha Institute of Medical and Technical Sciences, Chennai 602 105, Tamilnadu, India.
    Karthik Babu, N. B.
    Department of Mechanical Engineering, Assam Energy, Institute, A Centre of Rajiv Gandhi Institute of Petroleum Technology, Sivasagar 785697, India.
    Sas, Gabriel
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Jiang, Lin
    School of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing, 210094, China.
    Xu, Qiang
    School of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing, 210094, China.
    Restás, Ágoston
    Department of Fire Protection and Rescue Control, National University of Public Service, 1011, Budapest, Hungary.
    Das, Oisik
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand.
    Surface coated ZnO powder as flame retardant for wood: A short communication2023Inngår i: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 897, artikkel-id 165290Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In the present study, the ability of a coating of zinc oxide (ZnO) powder to improve the fire-safety of wood exposed to radiative heat flux was examined, focusing on the ignition time of the wood. To test ZnO's efficiency on the wood substrate, two different amounts of ZnO (0.5 and 1 g ZnO per dm2) were applied to the wood surface and exposed to radiative heat from a cone calorimeter wherein a pristine piece of wood with no ZnO treatment was taken as control. The experiments were conducted at three different irradiation levels i.e., 20, 35, and 50 kWm−2. The results showed that applying ZnO on the surface of the wood significantly increased the ignition time (TTI). For the three different heat fluxes, using 0.5 g ZnO per dm2 coating on the wood surface increased the TTI by 26–33 %. Furthermore, the application of 1 g of ZnO per dm2 generated a TTI increment of 37–40 %. All three irradiation levels showed similar trends in TTI. The micrographs taken before and after combustion showed no significant disparity in the morphology of ZnO. The agglomerated ZnO particles on the wood surface remained intact after combustion. This study demonstrates a facile method of using ZnO to delay the ignition of wood. This could potentially impart fire-safety to wooden structures/façades in wildland-urban interfaces and elsewhere by reducing flame spread.

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