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Use of nanomaterials for photocatalysis faces challenges such as complex synthesis, high cost, low scalability, and dependance on UV radiation for initiating the photocatalytic activity. We recently demonstrated scalable, one-pot syntheses of one-dimensional (1D) lepidocrocite-based nanofilaments (NFs), 1DL NFs, that have the potential to overcome some of the challenges. 1DL NFs are exceptionally stable in water, have a large surface to volume ratio, and sub-square-nanometer cross sections. Initial reports show the semiconducting nature of this material, with an indirect band gap energy of 4.0 eV, one of the highest ever reported for a titania material. In this work, we present a study of the electronic and optical properties of these newly discovered 1DL NFs using ultrafast transient optical absorption. We show that despite the large band gap of this material, sub-gap states can be accessed with visible light illumination only, and photoexcited species reveal decay times in the nanosecond scale. Long lived photoexcitations in the visible range, without assistance by UV illumination, pave the way for possible application in photocatalysis. 

Enabling the build-up of continental crust is a vital step in the stabilization of cratonic lithosphere. However, these initial crustal nuclei are commonly either destroyed by recycling or buried by younger rocks. In the Fennoscandian Shield, the oldest rocks are ca. 3.5 Ga, but ca. 3.7 Ga inherited and detrital zircons suggest the presence of an older, unexposed crustal substrate. We present U-Pb, O, and Hf isotope data from detrital zircons of three major Finnish rivers as well as zircon O and Hf isotope data from previously dated rocks of the Archean Suomujärvi and Pudasjärvi complexes, central Finland. Combined, these data indicate a previously unidentified ca. 3.75 Ga crustal nucleus in the Fennoscandian Shield. This adds to the growing number of Eoarchean nuclei recognized in Archean terranes around the globe, highlighting the importance of such nuclei in enabling the growth of continental crust. The isotope signatures of the Fennoscandian nucleus correlate with equivalent-aged rocks in Greenland, consistent with a common Eoarchean evolution for Fennoscandia and the North Atlantic craton.

 

It is well established that access to social supports is essential for engineering students’ persistence and yet access to supports varies across groups. Understanding the differential supports inherent in students’ social networks and then working to provide additional needed supports can help the field of engineering education become more inclusive of all students. Our work contributes to this effort by examing the reliability and fairness of a social capital instrument, the Undergraduate Supports Survey (USS). We examined the extent to which two scales were reliable across ability levels (level of social capital), gender groups and year-in-school. We conducted two item response theory (IRT) models using a graded response model and performed differential item functioning (DIF) tests to detect item differences in gender and year-in-school. Our results indicate that most items have acceptable to good item discrimination and difficulty. DIF analysis shows that multiple items report DIF across gender groups in the Expressive Support scale in favor of women and nonbinary engineering students. DIF analysis shows that year-in-school has little to no effect on items, with only one DIF item. Therefore, engineering educators can use the USS confidently to examine expressive and instrumental social capital in undergraduates across year-in-school. Our work can be used by the engineering education research community to identify and address differences in students’ access to support. We recommend that the engineering education community works to be explicit in their expressive and instrumental support. Future work will explore the measurement invariance in Expressive Support items across gender. 

Key static and dynamic properties of matter — from creation in the Big Bang to evolution into subatomic and astrophysical environments — arise from the underlying fundamental quantum fields of the standard model and their effective descriptions. However, the simulation of these properties lies beyond the capabilities of classical computation alone. Advances in quantum technologies have improved control over quantum entanglement and coherence to the point at which robust simulations of quantum fields are anticipated in the foreseeable future. In this Perspective article, we discuss the emerging area of quantum simulations of standard-model physics, outlining the challenges and opportunities for progress in the context of nuclear and high-energy physics. 

This work-in-progress (WIP) paper aims to elucidate how students have developed professional skills since the onset of the COVID-19 pandemic and who are the people who have provided skill development opportunities. Because of the way social distancing affected engineering education during the pandemic, developing professional skills may have been a challenge for engineering students. While online courses and virtual meetings allowed students to remain in contact with faculty and each other, the opportunities to continue having deep relationships (i.e., strong ties) were sparse. Our paper presents an early look at findings from the qualitative phase of an explanatory mixed methods study conducted with 1,234 undergraduates from 13 schools in the US. Our ongoing thematic qualitative analysis reveals that the changes that accompanied social distancing and periods of emergency remote teaching caused by COVID-19 have reinforced different opportunities to develop professional skills than prior to the pandemic. While some students expressed they had fewer opportunities to develop professional skills, participants also identified opportunities to (1) hone written communication skills when inperson discussions were reduced and (2) leverage knowledge from family members to continue developing professionally. Our next steps include finishing the qualitative analysis phase of the project and mixing the qualitative and quantitative data to develop overarching findings that the engineering education community can use to understand how students’ professional skills develop and how to promote that development even during times of educational disruption.