de Haas-van Alphen effect investigation of the electronic structure of Al substituted MgB_2

We report a de Haas-van Alphen (dHvA) study of the electronic structure of Al doped crystals of MgB$_2$. We have measured crystals with $\sim 7.5$% Al which have a $T_c$ of 33.6 K, ($\sim 14$% lower than pure MgB$_2$). dHvA frequencies for the $\sigma$ tube orbits in the doped samples are lower than in pure MgB$_2$, implying a $16\pm2$ reduction in the number of holes in this sheet of Fermi surface. The mass of the quasiparticles on the larger $\sigma$ orbit is lighter than the pure case indicating a reduction in electron-phonon coupling constant $\lambda$. These observations are compared with band structure calculations, and found to be in excellent agreement.Comment: 4 pages with figure

Correlation between TcT_c and anisotropic scattering in Tl2_2Ba2_2CuO6+δ_{6+\delta}

Angle-dependent magnetoresistance measurements are used to determine the isotropic and anisotropic components of the transport scattering rate in overdoped Tl$_2$Ba$_2$CuO$_{6+\delta}$ for a range of $T_c$ values between 15K and 35K. The size of the anisotropic scattering term is found to scale linearly with $T_c$, establishing a link between the superconducting and normal state physics. Comparison with results from angle resolved photoemission spectroscopy indicates that the transport and quasiparticle lifetimes are distinct.Comment: 5 pages, 3 figures, accepted for publication in Physical Review Letter

Iodido(N-phenyl­thio­urea)bis­(triphenyl­phosphine)copper(I)

The coordination geometry of the Cu atom in the title compound, [CuI(C7H8N2S)(C18H15P)2], is distorted tetra­hedral; it is coordinated by two triphenyl­phosphine P atoms, one S atom from N-phenyl­thio­urea (ptu) and one I atom. The crystal structure is stabilized by intra- and inter­molecular N—H⋯I and N—H⋯S inter­actions

Critical skills needs and challenges for STEM/STEAM graduates increased employability and entrepreneurship in the solar energy sector

© 2023 The Authors. This is an open access article available under a Creative Commons licence. The published version can be accessed at the following link on the publisher’s website: https://doi.org/10.1016/j.rser.2023.113776Energy produced by photovoltaic module (PVM) is poised to deliver the UN Sustainable Development Goal 7 (SDG-7) by 2030 and Net-Zero by 2050 but not until ample graduates with adequate Solar Energy Technology (SET) skills are produced by Higher education institutions (HEIs). Although PVM has witnessed significant penetration globally, the sustainability of the growth of the sector is challenged by attendant monotonic skilled labour shortages. The evolving growth imbalance is critical in the European Union (EU), limits her global competitiveness and necessitates the need to create wider awareness on the green technology to stimulate more production of solar energy sector (SES) specific skills graduates. Discussing the mismatch between the skills Europe needs and has in the SES, the study outlines key critical skills Science, Technology, Engineering and Mathematics (STEM) cum Arts (STEAM) graduates ought to possess to secure sector employment and the challenges limiting them from acquiring the competencies. The review is conducted via extensive study of relevant literature, analysis of interviews and observations. Academic, industrial, and entrepreneurial skills are identified as critical SES needs. Designing and running educational modules/curricula that embed the identified solar technology specialist skills on students and learners are proposed as vehicle to increase their employability and entrepreneurship. This study profiles trends and developments in the SES for stakeholders’ increased awareness while presenting the specialist skills in-demand for employment in the sector. The adoption of SET Training (SETechTra) curricula/modules by the EIs will substantially increase the production of industry-ready graduates whilst decreasing the SES skills gap.The authors acknowledge the European Union for funding the project entitled “Solar Energy Technology Training (SETechTra) Module for STEM Undergraduates” which produced this article under the Erasmus + Programme of the European Union. Project detail include: €392, 000.00 total grant; 36 months duration and agreement no.: 2020-1-UK01-KA203-079236. Innovate UK is also acknowledged for supporting the development of the mobile solar power system, project No. 83383.Published versio

Tunable Porous Organic Crystals: Structural Scope and Adsorption Properties of Nanoporous Steroidal Ureas

Previous work has shown that certain steroidal bis-(N-phenyl)ureas, derived from cholic acid, form crystals in the P61 space group with unusually wide unidimensional pores. A key feature of the nanoporous steroidal urea (NPSU) structure is that groups at either end of the steroid are directed into the channels and may in principle be altered without disturbing the crystal packing. Herein we report an expanded study of this system, which increases the structural variety of NPSUs and also examines their inclusion properties. Nineteen new NPSU crystal structures are described, to add to the six which were previously reported. The materials show wide variations in channel size, shape, and chemical nature. Minimum pore diameters vary from ∼0 up to 13.1 Å, while some of the interior surfaces are markedly corrugated. Several variants possess functional groups positioned in the channels with potential to interact with guest molecules. Inclusion studies were performed using a relatively accessible tris-(N-phenyl)urea. Solvent removal was possible without crystal degradation, and gas adsorption could be demonstrated. Organic molecules ranging from simple aromatics (e.g., aniline and chlorobenzene) to the much larger squalene (Mw = 411) could be adsorbed from the liquid state, while several dyes were taken up from solutions in ether. Some dyes gave dichroic complexes, implying alignment of the chromophores in the NPSU channels. Notably, these complexes were formed by direct adsorption rather than cocrystallization, emphasizing the unusually robust nature of these organic molecular hosts