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Venture Design Research: Description and Illustration
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The field of Information Systems (IS) has evolved significantly over the past three decades, driven by rapid advancements in information technology and research methodologies. Established methods like Action Research, Design Research, and Action Design Research have provided frameworks for research in connection to artifact development. However, there remains a pressing need for more engaged and impactful research approaches. In response, we propose Venture Design Research—a novel method emphasizing deep, long-term collaboration with practitioners, rooted in a combination of action design research and entrepreneurship theory. This approach positions IS researchers as active participants in societal innovation, expanding action design research from its early phases with explicit pursuit for arteracts with market impact in parallel with large-scale research programs. We describe and illustrate this method through an eight-year collaborative initiative with Swedish software developers focused on public sector digital transformation. The case study demonstrates how action design research can intersect and expand with entrepreneurial activities to address societal challenges, reshaping the researcher-practitioner relationship. We call for a rethinking of IS research, encouraging researchers to be both creators of knowledge and agents of programmatic technological- and organizational change, fostering a more engaged and impactful IS scholarship.Abstract
The field of Information Systems (IS) has evolved significantly over the past three decades, driven by rapid advancements in information technology and research methodologies. Established methods like Action Research, Design Research, and Action Design Research have provided frameworks for research in connection to artifact development. However, there remains a pressing need for more engaged and impactful research approaches. In response, we propose Venture Design Research—a novel method emphasizing deep, long-term collaboration with practitioners, rooted in a combination of action design research and entrepreneurship theory. This approach positions IS researchers as active participants in societal innovation, expanding action design research from its early phases with explicit pursuit for arteracts with market impact in parallel with large-scale research programs. We describe and illustrate this method through an eight-year collaborative initiative with Swedish software developers focused on public sector digital transformation. The case study demonstrates how action design research can intersect and expand with entrepreneurial activities to address societal challenges, reshaping the researcher-practitioner relationship. We call for a rethinking of IS research, encouraging researchers to be both creators of knowledge and agents of programmatic technological- and organizational change, fostering a more engaged and impactful IS scholarship
Youth, Imagination, and the Postdigital: Reflections from Participatory Speculative Design Activities
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Children and youth are growing up in a highly digitized world, where ongoing technological advancements create new forms of emotion, relationships, and agency, blurring the lines between physical and digital realms. In this study we explore futures imagined by youth, informed by theoretical contributions from interconnected fields of participatory speculative technology design and critical postdigital pedagogies, reliant as they are on imagination in support of emancipation. Through our reflections, we articulate some of the shared elements across these domains, aiming to more effectively interweave a transdisciplinary tapestry of postdigital imagination. Firstly, we emphasize the importance of creating safe spaces for youth to explore and critically examine their postdigital identities. We draw on participatory design traditions and suggest that participatory speculative design is effective for fostering critical discussions with youth about their postdigital experiences, hopes, and fears in a secure environment. Secondly, we align participatory speculative design with critical pedagogy concepts like critical consciousness, introducing the idea of socio-technical consciousness to encourage critical reflection and action on socio-technical issues. Lastly, we note that artefacts produced by young people through speculative design processes embody postdigital imaginaries, which can be used as a basis for engaging youth in discussion about underlying values and narratives. This process helps them envision more just futures within the complexities of a postdigital reality.Abstract
Children and youth are growing up in a highly digitized world, where ongoing technological advancements create new forms of emotion, relationships, and agency, blurring the lines between physical and digital realms. In this study we explore futures imagined by youth, informed by theoretical contributions from interconnected fields of participatory speculative technology design and critical postdigital pedagogies, reliant as they are on imagination in support of emancipation. Through our reflections, we articulate some of the shared elements across these domains, aiming to more effectively interweave a transdisciplinary tapestry of postdigital imagination. Firstly, we emphasize the importance of creating safe spaces for youth to explore and critically examine their postdigital identities. We draw on participatory design traditions and suggest that participatory speculative design is effective for fostering critical discussions with youth about their postdigital experiences, hopes, and fears in a secure environment. Secondly, we align participatory speculative design with critical pedagogy concepts like critical consciousness, introducing the idea of socio-technical consciousness to encourage critical reflection and action on socio-technical issues. Lastly, we note that artefacts produced by young people through speculative design processes embody postdigital imaginaries, which can be used as a basis for engaging youth in discussion about underlying values and narratives. This process helps them envision more just futures within the complexities of a postdigital reality
Impact of Initial Surface Roughness on Oxidation and Pickling Response of AISI 304L and 430
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This study examined the influence of surface roughness on oxide layer formation during annealing in an atmospheric controlled isothermal tube furnace for austenitic AISI 304L and ferritic AISI 430 as well as the pickling efficiency of neutral electrolyte pickling. Surface pretreatment prior to annealing consisted of electropolishing, mechanical polishing, and grinding. Annealing was performed at 1,150 °C/3 min and 1,050 °C/3 min for the austenitic and ferritic stainless steels, respectively. The pickling conditions were kept constant to evaluate the residual oxide layers after descaling between the different surface conditions. Surface roughness was measured as the surface average Ra. Oxide layer characterization was performed with FESEM–EDS and GDOES. Pickled sample surfaces were analyzed using 8-bit grayscale image processing to evaluate pickling efficiency from FESEM images taken from the descaled areas. The results showed that the progression of the oxide layer and its composition formed during annealing are influenced by the surface conditions of the stainless steels. The higher Ra on both materials increased the breakaway oxidation by increasing the formation of Fe-rich oxides on the surface. Pickling efficiency was also affected by surface conditions, and the best results were achieved from the lower Ra.Abstract
This study examined the influence of surface roughness on oxide layer formation during annealing in an atmospheric controlled isothermal tube furnace for austenitic AISI 304L and ferritic AISI 430 as well as the pickling efficiency of neutral electrolyte pickling. Surface pretreatment prior to annealing consisted of electropolishing, mechanical polishing, and grinding. Annealing was performed at 1,150 °C/3 min and 1,050 °C/3 min for the austenitic and ferritic stainless steels, respectively. The pickling conditions were kept constant to evaluate the residual oxide layers after descaling between the different surface conditions. Surface roughness was measured as the surface average Ra. Oxide layer characterization was performed with FESEM–EDS and GDOES. Pickled sample surfaces were analyzed using 8-bit grayscale image processing to evaluate pickling efficiency from FESEM images taken from the descaled areas. The results showed that the progression of the oxide layer and its composition formed during annealing are influenced by the surface conditions of the stainless steels. The higher Ra on both materials increased the breakaway oxidation by increasing the formation of Fe-rich oxides on the surface. Pickling efficiency was also affected by surface conditions, and the best results were achieved from the lower Ra
The Use of Artificial Reality in Road Safety: A Systematic Review
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Over the past decade, the use of artificial reality in road safety research has gained extensive research interest. However, summaries of the current state, challenges, and future directions of artificial reality in road safety are limited, and this poses a challenge to the successful advancement of the domain. This study conducted a systematic review to summarize trends in existing studies that used artificial reality to address road safety issues. Based on predefined search and selection criteria, 57 out of 1237 studies were selected and analyzed. The findings indicate that existing studies were focused on road safety education, attitude, and behavior change of road users, and examination of road traffic safety concepts. Less emphasis was placed on pedestrian safety and cognitive skills testing, especially among children and individuals with disabilities. This review revealed that virtual reality (VR) is the most used form of artificial reality studies, and most studies focus on testing the appropriateness of VR technology compared to real-world scenarios without adequately considering its effectiveness. Concepts related to presence and immersion are thus far largely ignored in road safety artificial reality research.Abstract
Over the past decade, the use of artificial reality in road safety research has gained extensive research interest. However, summaries of the current state, challenges, and future directions of artificial reality in road safety are limited, and this poses a challenge to the successful advancement of the domain. This study conducted a systematic review to summarize trends in existing studies that used artificial reality to address road safety issues. Based on predefined search and selection criteria, 57 out of 1237 studies were selected and analyzed. The findings indicate that existing studies were focused on road safety education, attitude, and behavior change of road users, and examination of road traffic safety concepts. Less emphasis was placed on pedestrian safety and cognitive skills testing, especially among children and individuals with disabilities. This review revealed that virtual reality (VR) is the most used form of artificial reality studies, and most studies focus on testing the appropriateness of VR technology compared to real-world scenarios without adequately considering its effectiveness. Concepts related to presence and immersion are thus far largely ignored in road safety artificial reality research
Thermodynamic properties of aqueous solutions of vanadate salts
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Vanadium is an important metal in modern society, predominantly used as an alloying element in steels to enhance mechanical strength. Other important applications can be found in various sectors, including batteries, catalysts, ceramics and even medicine. It is increasingly produced from secondary raw materials, such as slags from the metal industry, through processes combining pyro- and hydrometallurgy.
Understanding the aqueous chemistry of vanadium is important for developing greener production routes, improving existing processes, and evaluating the environmental impacts of vanadium pollution. The aim of this thesis was to develop a basis for modelling the thermodynamic properties of aqueous solutions of vanadate salts, focusing on the key binary systems NaVO3 – H2O and NH4VO3 – H2O.
Solubility and freezing point depression data for the above systems were experimentally determined and used with other literature data to develop and validate a model for the computation of various thermodynamic properties, including osmotic and activity coefficients, enthalpy changes, solubility and freezing point depression. The model was based on spectroscopic observations reported in the literature, and the non-ideality of the solution phase was modelled with the Pitzer equation. The extension of the model to ternary systems was investigated by modelling vanadate salt solubility in two such systems. Furthermore, the model was applied to estimate the level of saturation of ammonium vanadate in laboratory-scale vanadium recovery experiments performed with authentic materials.
The results obtained in this thesis extend the database of physical properties of aqueous vanadate salt solutions and enable the thermodynamically consistent calculation of various properties of these systems. This thesis also shows that spectroscopically determined equilibrium constants offer a useful starting point for the thermodynamic modelling of aqueous vanadate salt solutions. Original papers Manninen, M. A. E., Vielma, T. J., & Lassi, U. M. (2023). A Closer Look into Solubility in the Binary NaVO3 –H2O and NH4VO3 –H2O Systems from 298.15 to 333.15 K and 0.1 MPa. Journal of Chemical & Engineering Data, 68(9), 2500–2511. https://doi.org/10.1021/acs.jced.3c00367 https://doi.org/10.1021/acs.jced.3c00367 Self-archived version Kokko, M., Manninen, M., Hu, T., Lassi, U., Vielma, T., & Pesonen, J. (2024). Hydrometallurgical recovery of vanadium and calcium from electric arc furnace slag in hydrogen based steelmaking. Minerals Engineering, 217, 108966. https://doi.org/10.1016/j.mineng.2024.108966 https://doi.org/10.1016/j.mineng.2024.108966 Self-archived version Manninen, M. A. E., Vielma, T. J., & Lassi, U. M. (2025). Freezing point depression in the binary NaVO3 –H2O and NH4VO3 –H2O Systems at p = 0.1 MPa. The Journal of Chemical Thermodynamics, 207, 107491. https://doi.org/10.1016/j.jct.2025.107491 https://doi.org/10.1016/j.jct.2025.107491 Self-archived version Manninen, M. A. E., Vielma, T. J., & Lassi, U. M. (2025). A thermodynamic model for the NaVO3–H2O and NH4VO3–H2O systems in the temperature range from 272 to 350 K at atmospheric pressure. Journal of Molecular Liquids, 437, 128291. https://doi.org/10.1016/j.molliq.2025.128291 https://doi.org/10.1016/j.molliq.2025.128291 Self-archived version Tiivistelmä
Vanadiini on nyky-yhteiskunnalle tärkeä metalli, jonka merkittävin käyttötarkoitus on seostaminen teräksiin lujuusominaisuuksien parantamiseksi. Muita tärkeitä sovellusalueita ovat akku-, katalyytti-, keramiikka- ja lääketeollisuus. Sitä tuotetaan kasvavissa määrin sekundääriraaka-aineista, kuten metalliteollisuuden kuonista, pyro- ja hydrometallurgiaa yhdistävillä prosesseilla.
Vanadiinin vesiliuoskemian ymmärtäminen on tärkeää vihreämpien tuotantoreittien kehittämiseksi, nykyisten prosessien tehostamiseksi sekä vanadiinipäästöjen ympäristövaikutusten arvioimiseksi ja minimoimiseksi. Tämän väitöstyön tavoitteena oli kehittää perusta vanadaattisuolojen vesiliuosten termodynaamisten ominaisuuksien mallintamiselle, keskittyen kahteen keskeiseen binäärisysteemiin NaVO3 – H2O ja NH4VO3 – H2O.
Liukoisuutta ja jäätymispisteen alenemaa näissä systeemeissä mitattiin kokeellisesti, ja saatua dataa käytettiin muun kirjallisuusdatan ohella termodynaamisten ominaisuuksien, kuten osmoottisten- ja aktiivisuuskerrointen, entalpiamuutosten, liukoisuuden sekä jäätymispisteen laskentaan soveltuvan mallin kehittämisessä ja validoimisessa. Mallin perustana käytettiin kirjallisuudessa raportoituja spektroskooppisia havaintoja ja liuosfaasin epäideaalisuutta kuvattiin Pitzerin yhtälöllä. Mallin laajentamista kolmen komponentin systeemien kuvaukseen tutkittiin tarkastelemalla vandaattisuolojen liukoisuuksia kahdessa tällaisessa systeemissä. Kehitettyä mallia sovellettiin arvioimalla ammoniumvanadaatin kylläisyysastetta autenttisilla materiaaleilla suoritetuissa laboratoriomittakaavan vanadiinin talteenottokokeissa.
Väitöstutkimuksen tulokset laajentavat vanadaattisuolojen vesiliuosten fysikaalisten ominaisuuksien tietokantaa ja mahdollistavat useiden ominaisuuksien termodynaamisesti johdonmukaisen laskennan näissä systeemeissä. Lisäksi väitöstutkimus osoittaa, että spektroskooppisesti määritetyt tasapainovakiot tarjoavat käyttökelpoisen lähtökohdan vanadaattisuolojen vesiliuosten termodynaamisten ominaisuuksien mallintamiselle. Osajulkaisut Manninen, M. A. E., Vielma, T. J., & Lassi, U. M. (2023). A Closer Look into Solubility in the Binary NaVO3 –H2O and NH4VO3 –H2O Systems from 298.15 to 333.15 K and 0.1 MPa. Journal of Chemical & Engineering Data, 68(9), 2500–2511. https://doi.org/10.1021/acs.jced.3c00367 https://doi.org/10.1021/acs.jced.3c00367 Rinnakkaistallennettu versio Kokko, M., Manninen, M., Hu, T., Lassi, U., Vielma, T., & Pesonen, J. (2024). Hydrometallurgical recovery of vanadium and calcium from electric arc furnace slag in hydrogen based steelmaking. Minerals Engineering, 217, 108966. https://doi.org/10.1016/j.mineng.2024.108966 https://doi.org/10.1016/j.mineng.2024.108966 Rinnakkaistallennettu versio Manninen, M. A. E., Vielma, T. J., & Lassi, U. M. (2025). Freezing point depression in the binary NaVO3 –H2O and NH4VO3 –H2O Systems at p = 0.1 MPa. The Journal of Chemical Thermodynamics, 207, 107491. https://doi.org/10.1016/j.jct.2025.107491 https://doi.org/10.1016/j.jct.2025.107491 Rinnakkaistallennettu versio Manninen, M. A. E., Vielma, T. J., & Lassi, U. M. (2025). A thermodynamic model for the NaVO3–H2O and NH4VO3–H2O systems in the temperature range from 272 to 350 K at atmospheric pressure. Journal of Molecular Liquids, 437, 128291. https://doi.org/10.1016/j.molliq.2025.128291 https://doi.org/10.1016/j.molliq.2025.128291 Rinnakkaistallennettu versio Academic dissertation to be presented with the assent of the Doctoral Programme Committee of Technology and Natural Sciences of the University of Oulu for public defence in the Oulun Puhelin auditorium (L5), Linnanmaa, on 20 January 2026, at 9 a.m.Abstract
Vanadium is an important metal in modern society, predominantly used as an alloying element in steels to enhance mechanical strength. Other important applications can be found in various sectors, including batteries, catalysts, ceramics and even medicine. It is increasingly produced from secondary raw materials, such as slags from the metal industry, through processes combining pyro- and hydrometallurgy.
Understanding the aqueous chemistry of vanadium is important for developing greener production routes, improving existing processes, and evaluating the environmental impacts of vanadium pollution. The aim of this thesis was to develop a basis for modelling the thermodynamic properties of aqueous solutions of vanadate salts, focusing on the key binary systems NaVO3 – H2O and NH4VO3 – H2O.
Solubility and freezing point depression data for the above systems were experimentally determined and used with other literature data to develop and validate a model for the computation of various thermodynamic properties, including osmotic and activity coefficients, enthalpy changes, solubility and freezing point depression. The model was based on spectroscopic observations reported in the literature, and the non-ideality of the solution phase was modelled with the Pitzer equation. The extension of the model to ternary systems was investigated by modelling vanadate salt solubility in two such systems. Furthermore, the model was applied to estimate the level of saturation of ammonium vanadate in laboratory-scale vanadium recovery experiments performed with authentic materials.
The results obtained in this thesis extend the database of physical properties of aqueous vanadate salt solutions and enable the thermodynamically consistent calculation of various properties of these systems. This thesis also shows that spectroscopically determined equilibrium constants offer a useful starting point for the thermodynamic modelling of aqueous vanadate salt solutions.Tiivistelmä
Vanadiini on nyky-yhteiskunnalle tärkeä metalli, jonka merkittävin käyttötarkoitus on seostaminen teräksiin lujuusominaisuuksien parantamiseksi. Muita tärkeitä sovellusalueita ovat akku-, katalyytti-, keramiikka- ja lääketeollisuus. Sitä tuotetaan kasvavissa määrin sekundääriraaka-aineista, kuten metalliteollisuuden kuonista, pyro- ja hydrometallurgiaa yhdistävillä prosesseilla.
Vanadiinin vesiliuoskemian ymmärtäminen on tärkeää vihreämpien tuotantoreittien kehittämiseksi, nykyisten prosessien tehostamiseksi sekä vanadiinipäästöjen ympäristövaikutusten arvioimiseksi ja minimoimiseksi. Tämän väitöstyön tavoitteena oli kehittää perusta vanadaattisuolojen vesiliuosten termodynaamisten ominaisuuksien mallintamiselle, keskittyen kahteen keskeiseen binäärisysteemiin NaVO3 – H2O ja NH4VO3 – H2O.
Liukoisuutta ja jäätymispisteen alenemaa näissä systeemeissä mitattiin kokeellisesti, ja saatua dataa käytettiin muun kirjallisuusdatan ohella termodynaamisten ominaisuuksien, kuten osmoottisten- ja aktiivisuuskerrointen, entalpiamuutosten, liukoisuuden sekä jäätymispisteen laskentaan soveltuvan mallin kehittämisessä ja validoimisessa. Mallin perustana käytettiin kirjallisuudessa raportoituja spektroskooppisia havaintoja ja liuosfaasin epäideaalisuutta kuvattiin Pitzerin yhtälöllä. Mallin laajentamista kolmen komponentin systeemien kuvaukseen tutkittiin tarkastelemalla vandaattisuolojen liukoisuuksia kahdessa tällaisessa systeemissä. Kehitettyä mallia sovellettiin arvioimalla ammoniumvanadaatin kylläisyysastetta autenttisilla materiaaleilla suoritetuissa laboratoriomittakaavan vanadiinin talteenottokokeissa.
Väitöstutkimuksen tulokset laajentavat vanadaattisuolojen vesiliuosten fysikaalisten ominaisuuksien tietokantaa ja mahdollistavat useiden ominaisuuksien termodynaamisesti johdonmukaisen laskennan näissä systeemeissä. Lisäksi väitöstutkimus osoittaa, että spektroskooppisesti määritetyt tasapainovakiot tarjoavat käyttökelpoisen lähtökohdan vanadaattisuolojen vesiliuosten termodynaamisten ominaisuuksien mallintamiselle
Analysis of capacitance: multiple questions to one topic versus multiple solutions to one question
No full textAbstract
University physics, a core element of STEM education, increasingly integrates remote and in-person instruction, calling for more effective approaches to teaching challenging topics such as capacitance. This paper presents a structured problem-solving framework that combines multiple questions on a single topic with diverse solution strategies. Centered on capacitance problems involving various dielectric configurations, the framework progresses from fundamental to advanced cases to deepen students’ conceptual understanding, enhance analytical thinking, and promote flexible problem-solving. Designed to support learners with diverse backgrounds, the approach serves as a reference for developing similar problem-based tasks in physics education and provides a foundation for future studies on its impact in improving student engagement and comprehension in electromagnetism.Abstract
University physics, a core element of STEM education, increasingly integrates remote and in-person instruction, calling for more effective approaches to teaching challenging topics such as capacitance. This paper presents a structured problem-solving framework that combines multiple questions on a single topic with diverse solution strategies. Centered on capacitance problems involving various dielectric configurations, the framework progresses from fundamental to advanced cases to deepen students’ conceptual understanding, enhance analytical thinking, and promote flexible problem-solving. Designed to support learners with diverse backgrounds, the approach serves as a reference for developing similar problem-based tasks in physics education and provides a foundation for future studies on its impact in improving student engagement and comprehension in electromagnetism
Recent progress in understanding the regulation of fruit ripening in bilberry (Vaccinium myrtillus)
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Fruit ripening is a highly coordinated and complex process determining a wide range of characteristics affecting the fruit quality, such as flavour, nutritional value, shelf-life, and processing properties. The fruit set occurs after fertilization, followed by first an active cell division and a later cell expansion phase leading to ripening, which coincides with seed maturation. The ripening phase is regulated by a signalling network of thousands of genes that orchestrate the softening, and the accumulation of the secondary compounds and sugars in ripe fruits. Plant hormones, especially ethylene and abscisic acid (ABA) have major roles in the control of the ripening processes. Based on the burst of respiration rate and ethylene production and/or the peak in ABA production at the onset of ripening, fruits are classified as climacteric or non-climacteric fruits, respectively. We have studied the regulation of ripening in bilberry (Vaccinium myrtillus L.), traditionally classified as non-climacteric fruits, by analysing the role of the plant hormones, transcription factors, and the structural genes controlling the anthocyanin accumulation and the cell wall softening during the berry ripening. Our results have identified some upstream regulators of fruit ripening in bilberry and provided new knowledge on the R2R3 MYB and basic helix-loop-helix (bHLH) transcription factors, which are the key regulators of anthocyanin biosynthesis. Moreover, we have shown evidence of the role of ABA in controlling the ripening related anthocyanin accumulation in bilberry. Our recent results on metabolomic and proteomic profiling of bilberry indicate an increase in ethylene biosynthesis during bilberry fruit development coinciding with the ABA peak, raising a need for further studies and clearer determination between the classification of climacteric and non-climacteric fruits.Abstract
Fruit ripening is a highly coordinated and complex process determining a wide range of characteristics affecting the fruit quality, such as flavour, nutritional value, shelf-life, and processing properties. The fruit set occurs after fertilization, followed by first an active cell division and a later cell expansion phase leading to ripening, which coincides with seed maturation. The ripening phase is regulated by a signalling network of thousands of genes that orchestrate the softening, and the accumulation of the secondary compounds and sugars in ripe fruits. Plant hormones, especially ethylene and abscisic acid (ABA) have major roles in the control of the ripening processes. Based on the burst of respiration rate and ethylene production and/or the peak in ABA production at the onset of ripening, fruits are classified as climacteric or non-climacteric fruits, respectively. We have studied the regulation of ripening in bilberry (Vaccinium myrtillus L.), traditionally classified as non-climacteric fruits, by analysing the role of the plant hormones, transcription factors, and the structural genes controlling the anthocyanin accumulation and the cell wall softening during the berry ripening. Our results have identified some upstream regulators of fruit ripening in bilberry and provided new knowledge on the R2R3 MYB and basic helix-loop-helix (bHLH) transcription factors, which are the key regulators of anthocyanin biosynthesis. Moreover, we have shown evidence of the role of ABA in controlling the ripening related anthocyanin accumulation in bilberry. Our recent results on metabolomic and proteomic profiling of bilberry indicate an increase in ethylene biosynthesis during bilberry fruit development coinciding with the ABA peak, raising a need for further studies and clearer determination between the classification of climacteric and non-climacteric fruits
Superior Strength-Ductility Synergy in Fe-28Mn-8Al-1C Lightweight Steel via Cryogenic Supersonic Fine Particle Bombardment
No full textAbstract
Surface nano-crystallization treatment of Fe-28Mn-8Al-1C lightweight steel are realized by a cryogenic supersonic fine particle bombardment (CSFPB) technique. Optimal processing procedures were obtained by systematically investigating the effects of gas pressure and impact time on the surface integrity, microstructure and mechanical properties. Good surface integrity and small roughness have been obtained due to the low-temperature lubrication effect by liquid nitrogen, compared with room temperature SFPB. A gradient structure, i.e., nanosized grains at the surface, dislocation substructures and twins at subsurface, and undeformed matrix, form in the steel by means of CSFPB. Correspondingly, the microstructure-related microhardness decreases from surface onwards to matrix. Further detailed analysis reveals the deformation is coordinated via slip of dislocation and deformation twins. Deformation layer thickness increases monotonically with increases in gas pressure and impact time. Strengths of the CSFPBed steels are significantly enhanced, and the highest is achieved at 1.0 MPa gas pressure and 90 s impact time. Surface microcracks presenting on the surface due to higher gas pressure of longer impact time reduce the strengths, as these microcracks could act at nucleation sites for cracks that lead to failure. Nevertheless, the excellent plasticity of the steel retains even after CSFPB. The developed CSFPB methodology in this work can be a promising alternative for surface nano-crystallizations of alloys.Abstract
Surface nano-crystallization treatment of Fe-28Mn-8Al-1C lightweight steel are realized by a cryogenic supersonic fine particle bombardment (CSFPB) technique. Optimal processing procedures were obtained by systematically investigating the effects of gas pressure and impact time on the surface integrity, microstructure and mechanical properties. Good surface integrity and small roughness have been obtained due to the low-temperature lubrication effect by liquid nitrogen, compared with room temperature SFPB. A gradient structure, i.e., nanosized grains at the surface, dislocation substructures and twins at subsurface, and undeformed matrix, form in the steel by means of CSFPB. Correspondingly, the microstructure-related microhardness decreases from surface onwards to matrix. Further detailed analysis reveals the deformation is coordinated via slip of dislocation and deformation twins. Deformation layer thickness increases monotonically with increases in gas pressure and impact time. Strengths of the CSFPBed steels are significantly enhanced, and the highest is achieved at 1.0 MPa gas pressure and 90 s impact time. Surface microcracks presenting on the surface due to higher gas pressure of longer impact time reduce the strengths, as these microcracks could act at nucleation sites for cracks that lead to failure. Nevertheless, the excellent plasticity of the steel retains even after CSFPB. The developed CSFPB methodology in this work can be a promising alternative for surface nano-crystallizations of alloys
From the Periphery to a Global Player: Historical Evolution of the Qatari Banking Sector
No full textAbstract
The incredibly rapid and remarkable rise of the banking industry in Qatar contains valuable historical lessons that the extant research has so far overlooked. We rely on the elite interviews with the pivotal players of the banking industry over the last several decades and archival data to present a history of the banking sector in Qatar. Our paper explains the key milestones in Qatar’s banking sector and reveals the changes in Qatar’s economic structure vis-a-vis the evolution of the banking sector. The findings also reveal the vital role of British banks in the early phases of this evolution and how local family businesses played an instrumental role in developing local banks, along with targeted state policies. Thus, our paper distinctly sheds light on the lesser-known period of the 1950s to 1980s of the Qatari economy by analyzing the evolution of its banking sector.Abstract
The incredibly rapid and remarkable rise of the banking industry in Qatar contains valuable historical lessons that the extant research has so far overlooked. We rely on the elite interviews with the pivotal players of the banking industry over the last several decades and archival data to present a history of the banking sector in Qatar. Our paper explains the key milestones in Qatar’s banking sector and reveals the changes in Qatar’s economic structure vis-a-vis the evolution of the banking sector. The findings also reveal the vital role of British banks in the early phases of this evolution and how local family businesses played an instrumental role in developing local banks, along with targeted state policies. Thus, our paper distinctly sheds light on the lesser-known period of the 1950s to 1980s of the Qatari economy by analyzing the evolution of its banking sector