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Ultrasonic enhancement of ion transfer and lithium-ion battery properties during fast charging
No full textThe research reported in this thesis has explored the adoption of ultrasonic stimulation to stir the liquid electrolyte in lithium-ion (Li-ion) batteries through acoustic streaming. Electrolyte stimulation is understood to improve ion diffusion and mass transport, suppresses unwanted reactions and overpotentials, and reduces heat generation. This results in a safer and more efficient battery, extending its lifetime by minimising or avoiding lithium dendrite formation during fast charging. Such factors are critical to enhancing the performance of electric vehicle (EV) batteries and meeting future demands. Although ultrasonic stimulation is promising, the mechanisms have not yet been fully understood, limiting its optimisation and use in broader applications. This study addresses such gaps by investigating the influence of ultrasonic stimulation on induced liquid electrolytes and ion flow (ILEIF).A novelty of this work is the focus on reducing internal heat generated in the battery, which has been largely overlooked in the EV research field to date. Contrary to traditional external thermal management systems approaches, this work has investigated non-invasive strategies such as ultrasound ILEIF to achieve this, improving battery lifetimes, especially while fast charging. This work validates, both through simulations and experiments, that ultrasonic waves can permeate through the outer casing of a Li-ion battery and excite the electrolyte inside. Furthermore, varied ultrasound frequencies have been studied to find optimal parameters through the fluid motion within the battery cell. Experiments using micron scale particle image velocimetry (PIV) were employed to visualise fluid flow and measure induced velocities, revealing the impact of specific ultrasound parameters on fluid dynamics and validating numerical flow simulation. Comparisons were made with other thermal management reduction concepts (TMRCs), including extreme heat and rotating magnetic fields, in an application-specific environment to demonstrate that ultrasound is the most effective in improving ion deposition and minimising electrical resistance. The ultrasound parameters were optimised further during a series of electroplating experiments in a dummy battery cell rig, and their effects on ion mass transfer enhancement and distribution across electrode surfaces were demonstrated.Finally, testing on Li-ion battery cells confirmed that ultrasound stimulation effectively reduces battery cell impedance, lowering cell charge transfer resistance and enabling faster charging. It was shown that careful consideration must be given to ultrasound power level, transducer placement, and transducer size and shape to minimise internal structural deterioration while maximising performance gains. Thus, this research advances our understanding of ultrasonic stimulation by demonstrating its ability to enhance ion movement and distribution through acoustic mixing within the cell. As a non-invasive method, ultrasonic electrolyte stimulation offers a promising approach for improving battery performance and health, supporting faster charging capabilities, and developing more efficient and reliable EVs.</p
Sustainability orientation and entrepreneurial performance in resource-constrained contexts
No full textThis study examines how sustainability orientation shapes entrepreneurial performance in bottom-of-the-pyramid (BoP) markets by theorizing responsible entrepreneurship as a central mechanism and BoP orientation as a contextual contingency. Using survey data from 283 small and medium-sized enterprises (SMEs) in Ghana, we integrate perspectives from sustainability, entrepreneurship, and inclusive-market research to explain how firms pursuing sustainability create economic and social value under severe resource constraints. Our findings show that sustainability orientation promotes responsible entrepreneurship, and that this behavioral pathway translates into stronger entrepreneurial performance. This mediating effect highlights responsible entrepreneurship as a key strategic channel through which sustainability-driven firms realize superior outcomes. We also find that BoP orientation attenuates the performance benefits associated with responsible entrepreneurship. This moderating effect suggests a tension between deep social inclusivity and financial returns in low-income contexts. Implications for theory and practice are discussed.</p
The mental health challenges and impacts on physiotherapists working in male professional Norwegian football
No full textOur study investigated the mental health experiences of physiotherapists working in male professional Norwegian football. Semi-structured interviews with 16 male participants from 14 different football clubs in Norway’s top two divisions for men were conducted. The interviews revealed that the overall experience of working in football was positive. However, participants revealed several concerns regarding their role in professional football. Following a thematic analysis four themes were constructed: “In the firing line”, “Injuries that hurt both ways”, “Always on call – Often off balance”, and “Sidelining family for football.” These themes represented the most challenging aspects of being a physiotherapist in professional Norwegian football, how it affected the physiotherapists mental health, and the coping strategies they used when faced with these challenges. Areas for improvement are highlighted, including the need for increased social-support from governing bodies and clubs, improved work-life balance, improved communication, and more opportunities for professional development.</p
Rethinking the socio-economic nexus: judicial sense-making at the intersection of international economic law and the Colombian Constitution
No full textThis paper reframes Latin American debates about the limited potential of Constitutions to redistribute resources and power more equitably throughout society. It does so by exploring how the Colombian Constitutional Court has made sense of the role that constitutional law, interacting with international economic law, plays in the promotion of wealth and well-being. We argue that this sense-making constrains the radical potential of the Constitution by contributing to a particular articulation of the economy-society nexus, one that is underpinned by colonial and racial capitalist logics that obfuscate the exploitation and appropriation by capital of the wealth generated by our earth and labour, and their consequent immiseration. This is done through an analysis of four rulings which illustrate the Court’s production of a legal imaginary where social ‘goods’ like environmental protection and socio-economic rights are conceived of as positive externalities deriving from (trade-led) growth and development. Shedding light on the extractivist qualities of this legal sense-making matters because it exposes the constraining effects that the positing of a particular economic rationality as a universal truth (i.e. trade for growth leading to environmental protection and the amelioration of socio-economic inequalities) has on the possibility of thinking about different socio-legal-economic systems.</p
Multi-scale 3D printing of negative electrodes: A pathway to enhanced lithium-ion battery performance
No full textThis study introduces a multi-scale, multi-modal approach to the design and 3D printing of high-performance negative electrodes for lithium-ion batteries. Two types of printable inks were formulated using either alginate or carboxymethyl cellulose (CMC) as the primary binder, combined with styrene-butadiene rubber (SBR) and modified with a secondary fluid, 1-octanol. Rheological studies confirm that inks with secondary fluids exhibit higher viscosity and shear-thinning behaviour together with a yield stress of 20 Pa, compared to 14 Pa for non-modified formulations, enabling smooth extrusion and stable patterning in the direct ink writing (DIW) process. Cryo-SEM analysis confirmed the formation of well-aligned capillary networks that significantly reduced through-plane tortuosity from 6.3 to 4.5, enhancing ionic conductivity. Electrochemical testing revealed that 3D-printed electrodes outperformed traditional draw-down coated counterparts across multiple metrics. The dual-binder 3D-printed electrode demonstrated a 95 % discharge capacity retention at 5C, compared to 73 % for single-binder with octanol and only 19 % for alginate-based draw- down electrodes. Charge transfer resistance was reduced by over 40 % in printed structures. These results validate that ink-level and structural optimisation through a multi-scale design strategy can significantly improve battery performance, offering a viable route towards scalable, energy-dense, and high-power Li-ion technologies.</p
The transfer of employment practices across borders in multinational companies: from context to actors
No full textThis chapter addresses the issue of how multinational companies transfer expertise that was developed in one country to their operations around the world. It explores why multinationals seek to do this and the strategic roles that individuals play in the transfer process.</p
Vat photopolymerisation for additive manufacturing of zirconia and titanium
No full textVat photopolymerisation for additive manufacturing of zirconia and titanium</p
Centimanes v. Titans: right-wing populist governments’ treatment of foreign multinationals in East Central Europe
No full textThe treatment of foreign multinational enterprises (MNEs) by populist right-wing governments presents a puzzle: At times, these governments support, at times they take aggressive action against foreign MNEs. Allegorically speaking, rather than using their one hundred hands to slay the Titans like the Centimanes of Greek mythology, right-wing populist governments seem to use fifty hands of the state to support and fifty others to handicap foreign MNEs.
How can we explain the ambiguity of populist international business policy adopted by governments that adhere to economically nationalist rhetoric, ideologies, and goals? Our article contributes to these debates by theorizing the factors that determine right-wing populist governments’ multi-handed approach to MNEs. We empirically discuss these factors based on a mixed methods design by comparing host country cases (Hungary, Poland), home country cases (China/Russia vs. Western countries), and industry cases (finance, manufacturing). We demonstrate that the common denominator of the multi-handed approach by right-wing populist governments is their desire to decrease the presence of foreign multinationals in politically valuable sectors, but that this desire is tempered by political and economic restrictions, notably including their electoral fragility, the need for technology transfer, and limited alternative sources of foreign direct investment (FDI).</p
Views and downloads by geographical location via the Figshare API and Postman
No full textThis tutorial shows how Figshare administrators can use Postman and the Figshare Stats API to get the geographic location of view, downloads and shares.© the author</p
Lesion-specific design and oversizing as strategies for TAVI optimization: A patient-specific finite element study
No full textTranscatheter aortic valve implantation (TAVI) is a revolutionary intervention for aortic stenosis, yet complications such as paravalvular leakage (PVL) and excessive tissue stress remain prevalent, particularly in anatomies with elliptical aortic roots. This study develops geometric optimization strategies—specifically stent oversizing and lesion-specific design—to enhance sealing performance and reduce adverse mechanical interactions. A patient-specific finite element model of the aortic root was developed from CT imaging, and various stent designs were simulated, including alterations in strut thickness, width, and length. The evaluation compared conventional and modified stent configurations under standardized deployment conditions, including the effect of oversizing. Key metrics such as stress distribution, annulus gap area, and stent–aorta contact were particularly analyzed to assess device performance. A correlation analysis was conducted to identify interdependencies among the structural stiffness of the stents and deployment behaviors. Findings highlight the trade-offs between expansion, sealing, and mechanical response, emphasizing that tailored stent designs—particularly those with localized strut modifications—can achieve improved balance in anatomically challenging cases. The computational framework established in this study supports future TAVI optimization by linking stent design to patient-specific deployment outcomes.</p