Measuring Attitude toward Chemistry, Biology, and Math at a Hispanic-Serving Institution.

This work describes the evaluation of the Attitude toward the Subject of Chemistry Inventory (ASCI), as well as two modifications (one for measuring attitude toward math and one for measuring attitude toward biology), for college students at a Hispanic Serving Institution. Instrument reliability was tested via multiple administrations of the instruments, and confirmatory factor analysis supported a two-factor structure similar to an existing model of a revised version of the ASCI for all three instruments. The similar factor structure of the three instruments, coupled with interviews with students, provide validity evidence for the instruments and support an interpretation that one of the subscales aligns with a cognitive aspect of attitude while the other subscale aligns with an affective aspect. The results of these instruments indicate that students have a more positive attitude toward biology than either chemistry or math, and more positive affective attitude than cognitive attitude for all three subjects, although student attitudes show little change with respect to biology, chemistry, or math during a typical semester. However, major perturbations, such as switching to remote instruction midsemester, can lead to small but significant increases and decreases in attitude.

Computational and experimental characterization of a pyrrolidinium-based ionic liquid for electrolyte applications.

The development of Li-ion batteries for energy storage has received significant attention. The synthesis and characterization of electrolytes in these batteries are an important component of this development. Ionic liquids (ILs) have been proposed as possible electrolytes in these devices. Thus, the accurate determination of thermophysical properties for these solvents becomes important for determining their applicability as electrolytes. In this contribution, we present the synthesis and experimental/computational characterization of thermodynamic and transport properties of a pyrrolidinium based ionic liquid as a first step to investigate the possible applicability of this class of ILs for Li-ion batteries. A quantum mechanical-based force field with many-body polarizable interactions has been developed for the simulation of spirocyclic pyrrolidinium, [sPyr+], with BF4- and Li+. Molecular dynamics calculations employing intra-molecular polarization predicted larger heat of vaporization and self-diffusion coefficients and smaller densities in comparison with the model without intra-molecular polarization, indicating that the inclusion of this term can significantly effect the inter-ionic interactions. The calculated properties are in good agreement with available experimental data for similar IL pairs and isothermal titration calorimetry data for [sPyr+][BF4-].

If you are learner-centered and you know it, raise your hand: Perspectives on and implementation of pedagogical changes by science instructors during the COVID-19 pandemic.

Students at Minority-Serving Institutions (MSIs) faced significant hardships while trying to learn through emergency remote teaching (ERT) during the COVID-19 pandemic. Our research aims to investigate if science, technology, engineering, and mathematics (STEM) instructors thought about and enacted more learner-centered teaching practices to alleviate some of this stress encountered by their students. Using semi-structured interviews and classroom observations, we utilized inductive and deductive qualitative research methods to examine two questions: (1) To what extent were STEM instructor's perceived pedagogical changes learner-centered during ERT?; and (2) To what extent were STEM instructor's teaching behaviors and discourse practices learner-centered during ERT? Our findings revealed that during ERT, STEM instructors described using a variety of pedagogical changes that we identified as learner-centered under the Weimer framework, including ideas such as enacting flexible late policies and increased usage of formative assessment. Interestingly, we found that many of these learned-centered changes were happening outside of the classroom. Classroom observations assessing instructor behaviors and discourse demonstrated that STEM instructors enacted practices that aligned with Weimer's five constructs of learner-centered teaching. Our research highlights implications of learner-centered teaching practices for STEM instructors as well as researchers.

Increasing Student Engagement through Course Attributes, Community, and Classroom Technology: Lessons from the Pandemic.

While many STEM (science, technology, engineering, and mathematics) instructors returned to in-person instruction in fall 2021, others found themselves continuing to teach via online, hybrid, or hybrid flexible (i.e., hyflex) formats. Regardless of one's instructional modality, the findings from our own and other studies provided insight into effective strategies for increasing student engagement and decreasing cognitive overload. As part of this perspective, we included data from undergraduate students, many of whom are first generation and low income and from marginalized backgrounds, to identify instructional practices that helped them thrive and succeed during the recent COVID-19 pandemic. More specifically, we explored the various pedagogies and technologies utilized during emergency remote teaching to identify best practices as we considered the future of teaching. In sharing best practices at our institution, we aimed to provide a framework for deep reflection among the readers and the identification of practices to start, stop, and/or continue at their own institutions.

I will teach you here or there, I will try to teach you anywhere: perceived supports and barriers for emergency remote teaching during the COVID-19 pandemic.

BACKGROUND: Due to the COVID-19 pandemic, many universities moved to emergency remote teaching (ERT). This allowed institutions to continue their instruction despite not being in person. However, ERT is not without consequences. For example, students may have inadequate technological supports, such as reliable internet and computers. Students may also have poor learning environments at home and may need to find added employment to support their families. In addition, there are consequences to faculty. It has been shown that female instructors are more disproportionately impacted in terms of mental health issues and increased domestic labor. This research aims to investigate instructors' and students' perceptions of their transition to ERT. Specifically, during the transition to ERT at a research-intensive, Minority-Serving Institution (MSI), we wanted to: (1) Identify supports and barriers experienced by instructors and students. (2) Compare instructors' experiences with the students' experiences. (3) Explore these supports and barriers within the context of social presence, teaching presence, and/or cognitive presence as well as how these supports and barriers relate to scaffolding in STEM courses. RESULTS: Instructors identified twice as many barriers as supports in their teaching during the transition to ERT and identified casual and formal conversations with colleagues as valuable supports. Emerging categories for barriers consisted of academic integrity concerns as well as technological difficulties. Similarly, students identified more barriers than supports in their learning during the transition to ERT. More specifically, students described pre-existing course structure, classroom technology, and community as best supporting their learning. Barriers that challenged student learning included classroom environment, student availability, and student emotion and comfort. CONCLUSIONS: Together, this research will help us understand supports and barriers to teaching and learning during the transition to ERT. This understanding can help us better plan and prepare for future emergencies, particularly at MSIs, where improved communication and increased access to resources for both students and instructors are key. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s40594-022-00335-1.

Correction to: I will teach you here or there, I will try to teach you anywhere: perceived supports and barriers for emergency remote teaching during the COVID-19 pandemic.

[This corrects the article DOI: 10.1186/s40594-022-00335-1.].

Comparing Computational Predictions and Experimental Results for Aluminum Triflate in Tetrahydrofuran.

Exploring reliable electrolytes for aluminum ion batteries requires an in-depth understanding of the behavior of aluminum ions in ethereal-organic solvents. Electrolytes comprised of aluminum trifluoromethanesulfonate (Al-triflate) in tetrahydrofuran (THF) were investigated computationally and experimentally. Optimized geometries, redox potentials, and vibrational frequencies of species likely to be present in the electrolyte were calculated by density functional theory and then measured spectroscopically and electrochemically. Aluminum appears to be electrochemically active in THF with a reduction onset near 0 V versus Al/Al3+. Spectroscopic measurements reveal explicit evidence for the presence of two concentration-dependent ionic environments for the triflate anions, namely, outer-shell ligands and Al-bound triflates. Additionally, ionic conductivities of ∼2.5 mS/cm were measured for these electrolytes ∼0.8M.

A Combined Experimental and Computational Study of an Aluminum Triflate/Diglyme Electrolyte.

The physicochemical properties of aluminum trifluoromethanesulfonate in diglyme have been investigated. The spectroscopic and electrochemical properties have been examined to determine speciation, conductivity, and electrochemical stability. Gaussian calculations provide optimized molecular geometries and offer insight into the electrochemical behavior of the solutions. The ions in solution appear to exhibit very straightforward behavior, with contact ion pairs forming at very low concentrations. In addition, the electrochemical window of the electrolyte initially decreases with increasing salt concentration to a minimum value of approximately 5.5 V around 1 M and then steadily rises to a maximum value above 8 V.

High-density gold nanowire arrays by lithographically patterned nanowire electrodeposition.

Here we describe a new method for preparing multiple arrays of parallel gold nanowires with dimensions and separation down to 50 nm. This method uses photolithography to prepare an electrode consisting of a patterned nickel film on glass, onto which a gold and nickel nanowire array is sequentially electrodeposited. After the electrodeposition, the nickel is stripped away, leaving behind a gold nanowire array, with dimensions governed by the gold electrodeposition parameters, spacing determined by the nickel electrodeposition parameters, and overall placement and shape dictated by the photolithography.

Protection of lithium metal surfaces using chlorosilanes.

In this paper, we present a new approach for protecting metallic lithium surfaces based on a reaction between the thin native layer of lithium hydroxide present on the surface and various chlorosilane derivatives. The chemical composition of the resulting layer and the chemistry involved in layer formation were analyzed by polarization modulated infrared reflection absorption spectroscopy (PM-IRRAS), X-ray photoelectron spectroscopy (XPS), and energy dispersive X-ray analysis (EDX). Spectroscopy shows the disappearance of surface hydroxide groups and the appearance of silicon and chloride on the lithium surface. Differential scanning calorimetry (DSC) and electrochemical impedance spectroscopy (EIS) show that this surface treatment protects the lithium from certain gas-phase reactions and is ionically conductive.