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Sandinge, A., Fredriksson, H. & Blomqvist, P. (2023). Evaluation of smoke gas toxicity and smoke density of bus interior materials. Fire and Materials, 47(2), 270
Open this publication in new window or tab >>Evaluation of smoke gas toxicity and smoke density of bus interior materials
2023 (English)In: Fire and Materials, ISSN 0308-0501, E-ISSN 1099-1018, Vol. 47, no 2, p. 270-Article in journal (Refereed) Published
Abstract [en]

Materials used for interior parts in buses are today fire classified according to UNECE Regulation 118, evaluating the horizontal and vertical burning rates and the melting behaviour. However, in recent accidents, the smoke has been identified as the critical parameter for deaths. An evaluation has been made of six materials used as interior parts in busses and is presented in this paper. Fire testing was conducted according to UNECE R 118 and smoke production including smoke gas toxicity was further evaluated with the smoke chamber test, EN ISO 5659-2 and EN 17084. All six tested materials fulfilled the requirements of UNECE R 118; however, most materials showed fire properties which are not desirable, such as dark smoke and melting of large burning pieces. The tests with the smoke chamber showed that all materials gave a very high smoke production, in fact a smoke density value of the highest possible for the equipment to measure. This occurred only after a few minutes of test time. Thus, it can be concluded that this high smoke production will, in case of fire in a bus, reduce the visibility, and limit the ability of the passengers to safely evacuate. In addition, several toxic gases were detected in the smoke, both irritants and suffocating gases. © 2022 The Authors.

Place, publisher, year, edition, pages
John Wiley and Sons Ltd, 2023
Keywords
bus, fire, interior materials, regulation 118, smoke chamber, smoke density, smoke toxicity, Buses, Fires, Melting, Toxicity, Burning rate, Chamber tests, Classifieds, Melting behavior, Smoke production, Smoke
National Category
Human Geography
Identifiers
urn:nbn:se:ri:diva-60067 (URN)10.1002/fam.3095 (DOI)2-s2.0-85135531894 (Scopus ID)
Note

 Funding details: Ministry of Science, ICT and Future Planning, MSIP, NRF-2020R1A2C1009041, NRF-2020R1A5A1016518, NRF2021R1A2C1005359; Funding details: National Research Foundation of Korea, NRF; Funding text 1: This research was supported by the National Research Foundation of Korea (NRF) grant funded by the Korean government (MSIP) (NRF-2020R1A2C1009041, NRF2021R1A2C1005359, and NRF-2020R1A5A1016518).

Available from: 2022-09-21 Created: 2022-09-21 Last updated: 2024-03-03Bibliographically approved
Sandinge, A., Blomqvist, P. & Fredriksson, H. (2023). Fire safe bus interior materials – flame retardants and the effect on smoke production and smoke gas toxicity. In: Proceedings of Seventh International Conference on Fires in Vehicles: . Paper presented at Seventh International Conference on Fires in Vehicles, Stavanger, Norway, April 24-25, 2023. RISE Research Institutes of Sweden
Open this publication in new window or tab >>Fire safe bus interior materials – flame retardants and the effect on smoke production and smoke gas toxicity
2023 (English)In: Proceedings of Seventh International Conference on Fires in Vehicles, RISE Research Institutes of Sweden , 2023Conference paper, Published paper (Refereed)
Abstract [en]

The demands on bus interior products have increased with increasing sustainability, circularity and a reduction of harmful substances, today’s materials must be improved with regards of additives, such as flame retardants. A comprehensive study was made to evaluate the possibility to use phosphorous flame retardants (FRs) instead of the commonly used halogenated FRs compounded with ABS. The study showed that the fire performance could be improved with phosphorous FRs regarding heat release and smoke production. However, it was noted that the smoke production still was high, and that the smoke density was highest possible, i.e., no visibility through the smoke layer. Further testing of today’s bus interior materials showed that the high smoke density was achieved already after a few minutes of test time. Thus, it can be concluded that, in case of a fire, the visibility in the bus will be reduced and limit the ability of the passengers to safely evacuate. In addition, several toxic gases were detected in the smoke, both irritants and suffocating gases. The bus fire regulation R118 for interior materials basically deals with burning rate and melting through a fine mesh. Critical fire parameters such as smoke production and smoke toxicity is not dealt with. The R118 regulation need to be improved with these critical parameters in order to have fire safe materials inside the bus.

Place, publisher, year, edition, pages
RISE Research Institutes of Sweden, 2023
National Category
Civil Engineering
Identifiers
urn:nbn:se:ri:diva-71490 (URN)
Conference
Seventh International Conference on Fires in Vehicles, Stavanger, Norway, April 24-25, 2023
Note

The study was supported by the Swedish Centre for Chemical Substitution as well as Sweden’s strategicvehicle research and innovation partnership programme (FFI), via grant agreement 2019-03121.

Available from: 2024-01-26 Created: 2024-01-26 Last updated: 2024-03-03Bibliographically approved
El Houssami, M., Försth, M., Fredriksson, H., Drean, V., Guillaume, E., Hofmann-Böllinghaus, A. & Sandinge, A. (2023). Fire safety of interior materials of buses. Fire and Materials, 47(7), 910
Open this publication in new window or tab >>Fire safety of interior materials of buses
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2023 (English)In: Fire and Materials, ISSN 0308-0501, E-ISSN 1099-1018, Vol. 47, no 7, p. 910-Article in journal (Refereed) Published
Abstract [en]

This study provides an analysis on the fire safety of passengers and the fire protection of coaches and buses. A brief review of major bus fire incidents, an overview of current regulations in Europe, and their limitations are presented. The study finds that the current small-scale fire test methods described in UN ECE Reg No. 118 need to be replaced by test methods that can assess the reaction to fire of materials when exposed to ignition sources of varying sizes. To address these shortcomings, the study proposed an expert recommendation to update the material fire safety requirements and testing for buses. Additional measures are proposed, derived from objectives and strategies applied in other transport sectors, and can be tested through existing European and international standards, which are widely used by several industries. These measures aim to extend the time with tenable conditions for a safe evacuation in case of fire, reduce the degree of damage to buses, reduce the risk for fast and excessive thermal exposure on modern energy carriers needed for a more sustainable transport sector. © 2023 The Authors. 

Place, publisher, year, edition, pages
John Wiley and Sons Ltd, 2023
Keywords
Fire extinguishers, Fire protection, Risk assessment, Safety testing, 'current, Coach, Current regulations, Fire safety, Interior materials, Regulation, Small scale, Test method, Testing method, Transport sectors, Fires, bus, testing methods
National Category
Civil Engineering
Identifiers
urn:nbn:se:ri:diva-64227 (URN)10.1002/fam.3134 (DOI)2-s2.0-85149227479 (Scopus ID)
Note

 Correspondence Address:  M. Försth, RISE, Sweden; 

Available from: 2023-03-20 Created: 2023-03-20 Last updated: 2024-05-27Bibliographically approved
Haubold, T., Wolter, N., Sandinge, A., Blomqvist, P., Mayer, B. & Koschek, K. (2023). How Phosphorous Flame Retardant Additives Affect Benzoxazine-Based Monomer and Polymer Properties. Macromolecular materials and engineering, 308(11), Article ID 2300132.
Open this publication in new window or tab >>How Phosphorous Flame Retardant Additives Affect Benzoxazine-Based Monomer and Polymer Properties
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2023 (English)In: Macromolecular materials and engineering, ISSN 1438-7492, E-ISSN 1439-2054, Vol. 308, no 11, article id 2300132Article in journal (Refereed) Published
Abstract [en]

The phosphorous-based flame retardant additives poly(m-phenylene methylphosphonate) (PMP) and resorcinol bis(diphenyl phosphate) (RDP) are reacted with bisphenol F and aniline–based benzoxazine (BF-a). DSC, rheological analysis, FT-IR, and soxhlet extraction reveal the covalent incorporation of both FR additives—initiating phenols in PMP structure as well as free phenols generated via transesterification reaction in the case of RDP. In contrast to PMP, RDP elongates the processing window but decreases the thermo–mechanical properties. Both additives increase the resistance in reactions against small flames with solely a phosphorous loading of 0.3 wt%, resulting in a V-0 rating and an improvement in the OI value by up to 2% for RDP and 4% for PMP. Both FRs reduce the heat release rate but increase the smoke production and the smoke toxicity in the case of RDP. 

Place, publisher, year, edition, pages
John Wiley and Sons Inc, 2023
Keywords
benzoxazine polymerization, fire retardants, flammability, mechanical properties, phosphorous, Additives, Aniline, Esters, Flame retardants, Phosphorus, Polymerization, Smoke, Benzoxazine, Bisphenol F, Flame-retardant additives, Methylphosphonates, Polymer properties, Rheological analysis, Soxhlet extraction, Transesterification reaction, Phenols
National Category
Engineering and Technology
Identifiers
urn:nbn:se:ri:diva-65738 (URN)10.1002/mame.202300132 (DOI)2-s2.0-85163380918 (Scopus ID)
Note

The authors gratefully acknowledge the support of the Shift2Rail Joint Undertaking under the European Union's Horizon 2020 research and innovation program (Mat4Rail with the grant agreement number 777595), and of the Federal Ministry for Economic Affairs and Climate Action (GreenLight, 03SX515E)

Available from: 2023-08-08 Created: 2023-08-08 Last updated: 2024-06-10Bibliographically approved
Sandinge, A., Blomqvist, P. & Rahm, M. (2022). A modified specimen holder for cone calorimeter testing of composite materials to reduce influence from specimen edges. Fire and Materials, 46(1), 80
Open this publication in new window or tab >>A modified specimen holder for cone calorimeter testing of composite materials to reduce influence from specimen edges
2022 (English)In: Fire and Materials, ISSN 0308-0501, E-ISSN 1099-1018, Vol. 46, no 1, p. 80-Article in journal (Refereed) Published
Abstract [en]

ISO 5660-1 specifies the cone calorimeter method for characterizing the ignition and surface burning behavior of materials. The specimen is irradiated through a square opening in the frame of the specimen holder. The frame is intended to protect the edges of the specimen from irradiation but covers the edges with only a few mm. In tests with products such as composite laminates and sandwich wall panels, the production of pyrolysis gases from the edges and, in many cases, burning have been observed. Early contribution from the edges in the test is not representative for surface burning. A modified specimen holder was developed with a larger specimen size to allow better protection of the edges. The opening for exposure to irradiance of the retainer frame is circular and of the same area as that of the original frame. The distance between the exposed surface and the specimen edges is larger in order to prevent early exposure of edges. Tests using the standard specimen holder resulted in pyrolysis and burning from edges that took place outside of the specimen holder. Comparative tests using the modified specimen holder showed that it prevented the exposure and pyrolysis from edges for an extended time. However, the influence on ignition time and peak heat release due to the increased size of the modified specimen holder has not been characterized fully, and test results should not be used for direct comparison with those of the standard holder.

Place, publisher, year, edition, pages
John Wiley and Sons Ltd, 2022
Keywords
composite laminates, cone calorimeter, edge burning, heat release rate, specimen holder, Calorimeters, Laminated composites, Pyrolysis, Burning behavior, Comparative tests, Composite laminate, Exposed surfaces, Sandwich wall panels, Square openings, Standard specimens, Testing
National Category
Composite Science and Engineering
Identifiers
urn:nbn:se:ri:diva-52907 (URN)10.1002/fam.2949 (DOI)2-s2.0-85101490331 (Scopus ID)
Note

Funding details: Seventh Framework Programme, FP7, 246037; Funding details: Seventh Framework Programme, FP7; Funding details: Horizon 2020, 723246; Funding text 1: The research reported here was conducted within the EU project FIRE‐RESIST which received funding from the European Community's Seventh Framework Programme (FP7/2007‐2013) under grant agreement No. 246037. The research is also a part of the RAMSSES project which has received funding under the European Union's Horizon 2020 research and innovation programme under the grant agreement No 723246.

Available from: 2021-04-08 Created: 2021-04-08 Last updated: 2023-06-05Bibliographically approved
Sjögren, P., Sandinge, A. & Li, Z. (2022). Kompositer för en hållbar sjöfart. Trafikverket
Open this publication in new window or tab >>Kompositer för en hållbar sjöfart
2022 (Swedish)Report (Other academic)
Abstract [en]

This pre-study “Composites for sustainable shipping” was carried out as a response to the lightweight industry's desire to map the remaining barriers that still prevent more and larger applications of composite materials in shipping. Ever since the first-generation Visby corvettes were launched in the early 2000s, the industry has shown that it is possible to manufacture large composite ships with good strength and seaworthiness with low maintenance requirements. Despite this, the potential of modern lightweight materials for shipping is underutilized. Essentially, the stumbling blocks can be divided into three areas: Fire properties, competence, and economy. To this can be added uncertainty during operation in cold climates (ice properties) and recycling issues, as obstacles to more widespread use of composites. Within the framework of this study, ice calculations were carried out to demonstrate new methods of optimising composite hulls, and the results of an earlier preliminary study were supplemented with fire tests for new fire protections at the request of the industry. Furthermore, the results of the preliminary study show that composites have a given place in future shipping in several and new ways. With the rise of electric powertrains, just as for the aviation and automotive industries, light weight is a prerequisite to be able to go from a fuel with a high energy density to one with a lower. Lightweight is an enabler for an electric fleet. Electric operation and fossilfree energy carriers also mean direct innovation opportunities linked to material selection. Structural batteries, airframe technology, thermally and electrically conductive lightweight materials are areas we see emerging in the wake of the progress of electric operation.

Abstract [sv]

Förstudien ”Kompositer för en hållbar sjöfart” genomfördes som ett svar på lättviktsindustrins vilja att kartlägga de stötestenar som fortfarande hindrar fler och större tillämpningar av kompositmaterial inom sjöfarten. Allt sedan den första generationens Visby-korvetter sjösattes under tidigt 2000-tal har industrin visat att det går att tillverka stora fartyg i komposit med goda hållfasthets- och sjöegenskaper med låga underhållskrav. Trots detta så är potentialen i moderna lättviktsmaterial för sjöfarten underutnyttjad. I huvudsak kan stötestenarna delas upp i tre områden: brandegenskaper, kompetens och ekonomi. Därtill kan läggas osäkerhet vid drift i kalla klimat (isegenskaper) och återvinningsfrågor, som hinder för mer utbrett nyttjande av kompositer. Inom ramen för studien genomfördes isberäkningar för att visa på nya metoder att optimera kompositskrov och en tidigare förstudies resultat kompletterades med brandprover för nya brandskydd på begäran från industrin. Samtidigt visar förstudiens resultat att kompositer har en given plats i framtidens sjöfart på flera och nya sätt. Med framväxten av elektriska drivlinor är, precis som för flyg- och bilindustri, lättvikt en förutsättning för att kunna gå från ett bränsle med hög energidensitet till ett med lägre. Lättvikt är en möjliggörare för en eldriven flotta. Eldrift och fossilfria energibärare innebär också direkta innovationsmöjligheter kopplade till materialval. Strukturella batterier, bärplansteknik, termiskt och elektriskt ledande lättviktsmaterial är områden vi ser växa fram i kölvattnet av eldriftens framfart.

Place, publisher, year, edition, pages
Trafikverket, 2022. p. 58
Series
Lighthouse Reports
National Category
Composite Science and Engineering
Identifiers
urn:nbn:se:ri:diva-61183 (URN)
Note

I samarbete med: FMV, Green City Ferries,  SAAB, Kockums, Swede Ship Composite AB, Poseidon Konsult AB, BPAB samt Teknos. Detta projekt har genomförts inom Trafikverkets branschprogram Hållbar sjöfart, som drivs av Lighthouse. 

Available from: 2022-11-21 Created: 2022-11-21 Last updated: 2023-05-09Bibliographically approved
Sandinge, A., Ukaj, K. & Sjögren, A. (2022). Kompositlösningar inom sjöfarten - KOMPIS.
Open this publication in new window or tab >>Kompositlösningar inom sjöfarten - KOMPIS
2022 (Swedish)Report (Other academic)
Abstract [en]

Composite solutions for marine applications - KOMPIS. Extensive research has been devoted to improving commercial shipping’s environmental footprint by focusing on lightweight constructions during the past decade. The biggest challenge to replacing steel structures with fibre-reinforced polymer (FRP) is ensuring fire safety at sea. Ongoing electrification and its dependence on weight reduction has further increased the demand for lightweight solutions, and in particular composite solutions that provide satisfactory fire safety. The purpose of this study was to inform regional actors concerning the feasibility of FRP composite in ship structures to respond to the growing demand for fire-safe composite materials, and as a step towards more environmentally friendly vessels. Within the project, a comprehensive literature study was conducted to find available components for a composite laminate on the market. A comprehensive list with polymers, fibres and additives was compiled. A hybrid composite laminate consisting of fenol/glass and vinylester/glass was manufactured and protected with an intumescent coating. The composite laminate was evaluated with regards to fire performance and mechanical properties. The results showed no ignition in the fire testing and good mechanical performance.

Publisher
p. 59
Series
RISE Rapport ; 2022:04
Keywords
composite material, FRP, laminate, reaction-to-fire, ISO 5660-1, Part 5, mechanical performance
National Category
Materials Engineering
Identifiers
urn:nbn:se:ri:diva-57532 (URN)978-91-89561-19-9 (ISBN)
Note

Projektet KOMPIS – Kompositlösningar inom sjöfarten, har erhållit finansiering från Västra Götalandsregionen enligt diarienummer RUN 2010-00520.

Available from: 2022-01-07 Created: 2022-01-07 Last updated: 2023-05-09Bibliographically approved
Bachinger, A., Sandinge, A., Lindqvist, K., Strid, A. & Gong, G. (2022). Systematic evaluation of bromine-free flame-retardant systems in acrylonitrile-butadiene-styrene. Paper presented at 2021/11/15. Journal of Applied Polymer Science, 139(13), Article ID 51861.
Open this publication in new window or tab >>Systematic evaluation of bromine-free flame-retardant systems in acrylonitrile-butadiene-styrene
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2022 (English)In: Journal of Applied Polymer Science, ISSN 0021-8995, E-ISSN 1097-4628, Vol. 139, no 13, article id 51861Article in journal (Refereed) Published
Abstract [en]

A systematic investigation of phosphorus-based flame-retardant (PFR) systems in acrylonitrile-butadiene-styrene (ABS) is presented. The effect of various PFRs, combinations thereof and influence of different synergists is studied in terms of fire and mechanical performance, as well as toxicity of resulting ABS. Sustainable flame-retardant systems with a promising effect on the fire-retardant properties of ABS are identified: A combination of aluminum diethylphosphinate and ammonium polyphosphate is shown to exhibit superior flame-retardant properties in ABS compared to other studied PFRs and PFR combinations. Among a variety of studied potential synergists for this system, a grade of expandable graphite with a high-initiation temperature and a molybdenum-based smoke suppressant show the most promising effect, leading to a significant reduction of the peak heat release rate as well as the smoke production rate. Compared to current state-of-the-art brominated flame-retardant for ABS, the identified flame-retardant systems reduce the maximum smoke production rate by 70% and the peak heat release rate by 40%. However, a significant reduction of the impact performance of the resulting ABS is identified, which requires further investigation.

Place, publisher, year, edition, pages
John Wiley & Sons, Ltd, 2022
Keywords
blends, flame retardance, mechanical properties, thermal properties, thermoplastics
National Category
Textile, Rubber and Polymeric Materials
Identifiers
urn:nbn:se:ri:diva-56830 (URN)10.1002/app.51861 (DOI)2-s2.0-85118746839 (Scopus ID)
Conference
2021/11/15
Available from: 2021-11-15 Created: 2021-11-15 Last updated: 2023-05-23Bibliographically approved
Sandinge, A., Blomqvist, P., Sørensen, L. & Dederichs, A. (2022). The Effect of Accelerated Ageing on Reaction-to-Fire Properties–Composite Materials. Fire technology, 58(3), 1305-1332
Open this publication in new window or tab >>The Effect of Accelerated Ageing on Reaction-to-Fire Properties–Composite Materials
2022 (English)In: Fire technology, ISSN 0015-2684, E-ISSN 1572-8099, Vol. 58, no 3, p. 1305-1332Article in journal (Refereed) Published
Abstract [en]

As material age, the durability, strength, and other mechanical properties are impacted. The lifespan of a material generally decreases when exposed to weathering conditions such as wind, temperature, humidity, and light. It is important to have knowledge of how materials age and how the material properties are affected. Regarding materials´ fire behaviour and the effect of ageing on these properties, the knowledge is limited. The research questions of the current work are: Are the fire properties of composite materials affected by ageing? And if so, how is it affected? The study is on material at Technology Readiness Level 9 (TRL). In this study, three composite fibre laminates developed for marine applications were exposed to accelerated ageing. Two different ageing conditions were selected, thermal ageing with an increased temperature of 90°C and moisture ageing in a moderately increased temperature of 40°C and a relative humidity of 90%. Samples were collected after one, two and four weeks of ageing. The reaction-to-fire properties after ageing was evaluated using the ISO 5660–1 cone calorimeter and the EN ISO 5659–2 smoke chamber with FTIR gas analysis. The test results showed that the fire behaviour was affected. Two of the composite laminates, both phenolic/basalt composites, showed a deteriorated fire behaviour from the thermal ageing and the third composite laminate, a PFA/glass fibre composite, showed an improved fire behaviour both for thermal and moisture ageing. The smoke toxicity was affected by the accelerated ageing, especially for the PFA/glass fibre composite that showed a higher production of CO and HCN, both for the thermal aged and the moisture aged samples. © 2021, The Author(s).

Place, publisher, year, edition, pages
Springer, 2022
Keywords
Accelerated ageing, Composite laminates, Cone calorimeter, Moisture exposure, Reaction-to-fire, Smoke density, Thermal exposure, Toxicity, Durability, Fires, Laminated composites, Marine applications, Smoke, %moisture, Composite laminate, Fire behaviour, Fire properties, Reaction to fire, Moisture
National Category
Composite Science and Engineering
Identifiers
urn:nbn:se:ri:diva-57366 (URN)10.1007/s10694-021-01197-9 (DOI)2-s2.0-85119970365 (Scopus ID)
Note

Funding details: Horizon 2020 Framework Programme, H2020, 723246; Funding text 1: The research presented is a part of the RAMSSES project which has received funding under the European Union’s Horizon 2020 research and innovation programme under the grant agreement No 723246.

Available from: 2021-12-17 Created: 2021-12-17 Last updated: 2023-06-05Bibliographically approved
Blomqvist, P. & Sandinge, A. (2021). An experimental evaluation of the equivalence ratios in tests apparatus used for fire effluent toxicity studies. Fire and Materials, 45(8), 1085-1095
Open this publication in new window or tab >>An experimental evaluation of the equivalence ratios in tests apparatus used for fire effluent toxicity studies
2021 (English)In: Fire and Materials, ISSN 0308-0501, E-ISSN 1099-1018, Vol. 45, no 8, p. 1085-1095Article in journal (Refereed) Published
Abstract [en]

An experimental evaluation was conducted on the bench-scale test methods most commonly applied for generating data for fire toxicity assessments. The test methods evaluated were ISO/TS 19700, ISO 5660-1 with the controlled atmosphere box, and ISO 5659-2. Toxic gases were quantitatively analyzed using Fourier transfer infrared spectroscopy. Tests were made with 11 different insulation materials and polymethylmethacrylate as a reference material. The evaluation made was on the combustion conditions in the test apparatus, not generally on the precise yields measured. The evaluation focused on the ventilation conditions created in flaming combustion tests. It was seen that ISO/TS 19700 currently offers the best means among the three test methods evaluated for conducting tests at pre-determined and controlled equivalence ratios. The controlled-atmosphere cone calorimeter does not give a prolonged steady flaming combustion period for most materials and the influence of vitiation was difficult to predict and limiting in achieving higher equivalence ratios, with the test settings applied. ISO 5659-2 generally accumulates a mixture of gases from periods of both flaming and nonflaming combustion in a test, and the yields measured do not, in those cases, represent any specific combustion stage. For materials not showing flaming combustion, for example, mineral fiber products, the influence on the test conditions regarding oxygen consumption and heat generation from the material itself is limited compared to burning materials. However, there were specific properties and limitations of the different test methods observed that are important to consider. 

Place, publisher, year, edition, pages
John Wiley and Sons Ltd, 2021
Keywords
bench-scale test methods, combustion conditions, fire toxicity
National Category
Building Technologies
Identifiers
urn:nbn:se:ri:diva-53528 (URN)10.1002/fam.2995 (DOI)2-s2.0-85107348995 (Scopus ID)
Available from: 2021-06-17 Created: 2021-06-17 Last updated: 2023-06-05Bibliographically approved
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0002-7001-9757

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