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  1. This study focuses on the effectiveness of learning transfer-focused or transfer-focused lab report writing instructional modules on engineering undergraduates’ lab report writing in entry-level engineering laboratory courses. The modules are novel due to their shared language to describe and reinforce foundational writing terms used by the writing faculty and are ready for immediate use by engineering lab instructors. Three different universities, consisting of a polytechnical university, a liberal arts-anchored private university, and a branch campus of a research-one land grant university, participated. Student lab report samples from six various sophomore-level engineering courses were collected. For the control group, none of the participating lab instructors accessed the transfer-focused modules (academic years of 2019-2020 and 2020-2021); sixty-four control group lab report samples were collected (n = 64). In the academic year 2021-2022, the lab instructors had access to the transfer-focused modules via the web to be encouraged to update their lab instructions; the experimental group lab report samples were collected from forty-two students (n = 42). Using defined writing outcomes, a panel of engineering lab instructors assessed the participating students’ early (one of the first reports in the class) and late lab reports (written near the end of the course). The lab report assessment analysis indicates that only 30% of the control group students could write their early lab reports at a satisfactory level, while 60% of the experimental group students reached a satisfactory level in their early labs. For both early and late lab reports, the experimental group students outperformed most outcomes over the control group. The notably improved outcomes were related to audience awareness, data presentation, data analysis, and data interpretation. The transfer-focused lab report writing pedagogy enhanced engineering undergraduates’ ability to engage in critical thinking practices, including analysis, interpretation, and evaluation of their lab data/products. Additionally, students appeared to improve their awareness of a technical audience, expecting engineering language, styles, and conventions commonly shared by writers in engineering. 
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  2. Graphene layers placed on SrTiO3 single-crystal substrates, i.e., templates for remote epitaxy of functional oxide membranes, were investigated using temperature-dependent confocal Raman spectroscopy. This approach successfully resolved distinct Raman modes of graphene that are often untraceable in conventional measurements with non-confocal optics due to the strong Raman scattering background of SrTiO3. Information on defects and strain states was obtained for a few graphene/SrTiO3 samples that were synthesized by different techniques. This confocal Raman spectroscopic approach can shed light on the investigation of not only this graphene/SrTiO3 system but also various two-dimensional layered materials whose Raman modes interfere with their substrates.

     
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  3. The quantum efficiency and mean transverse energy of electrons emitted from a cathode determine the quality of beams generated from photoinjectors. The nitrogen-incorporated ultrananocrystalline diamond, (N)UNCD, is a new class of robust semiconductor photocathodes, which has been considered in photoinjectors for high peak current extraction. In this work, we measure the spectral response in quantum efficiency, photoemission energy spectra, and mean transverse energy of the (N)UNCD photocathode using a photoemission electron microscope. The observed quantum efficiency was comparable to that of copper photocathodes. Photoemission spectra showed the evidence of scattering of electrons before emission. This relaxation of electrons due to scattering is also observed in the spectral response of the mean transverse energy. The mean transverse energy is limited to ∼70 meV at the threshold. We attribute this to the physical and chemical roughness of the (N)UNCD photocathode and, hence, smoother films will be required to further reduce the mean transverse energy obtained from the (N)UNCD photocathode.

     
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  4. ABSTRACT

    We present the results of high-resolution adaptive optics imaging observations of four kinematically identified recoiling supermassive black hole (rSMBH) candidates. Ellipse fitting was carried out to measure the spatial offset between the active galactic nucleus (AGN) and the centre of the host galaxy. Two rSMBH candidates (J1713 + 3523 and J2054 + 0049) are found to be offset AGN. However, the Very Long Baseline Array 1.5 GHz continuum imaging observation and spectral decomposition of the [O iii]5007 line suggest that J1713 + 3523 is a dual AGN and its spatial offset is not due to a recoil event. The spatial offset between the AGN and the centre of the host galaxy in J2054 + 0049 is 0.06 ± 0.01 arcsec (201 ± 22 pc). Spectral decomposition of J2054 + 0049 also suggests that it could be a dual AGN system and the measured spatial offset may not be due to a recoil event.

     
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  5. Abstract There has been considerable recent interest in the high-pressure behavior of silicon carbide, a potential major constituent of carbon-rich exoplanets. In this work, the atomic-level structure of SiC was determined through in situ X-ray diffraction under laser-driven ramp compression up to 1.5 TPa; stresses more than seven times greater than previous static and shock data. Here we show that the B1-type structure persists over this stress range and we have constrained its equation of state (EOS). Using this data we have determined the first experimentally based mass-radius curves for a hypothetical pure SiC planet. Interior structure models are constructed for planets consisting of a SiC-rich mantle and iron-rich core. Carbide planets are found to be ~10% less dense than corresponding terrestrial planets. 
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  6. Ethics and social responsibility are often viewed as key areas of concern for many engineering educators and professional engineers. Thus, it is important to consider how students and professionals understand and navigate ethical issues, explore how such perceptions and abilities change over time, and investigate if certain types of interventions and experiences (e.g., coursework, training, service activities, etc.) impact individual participants. The breadth of engineering as a profession also raises questions about how ethics and social responsibility are understood across a wide range of disciplines, subfields, and industry sectors. Recognizing a need for more empirical research to address such questions, our research team carried out a five year, longitudinal, mixed-methods study to explore students’ perceptions of ethics and social responsibility. This study relied on repeated use of quantitative measures related to ethics, along with qualitative interviews to explore how students’ perceptions of these issues change across time, between institutions, and in response to participation in certain experiences. Additionally, we are now initiating a follow-on study where we will collect survey and interview data from our previous participants now that most of them are in full-time job roles and/or pursuing graduate degrees, as well as from a new group of early career engineers to enlarge our sample. In this paper, we first give an overview of key research findings from our ongoing research that have been published or are under review. The second major part of this paper delves into some specific theoretical and methodological questions and challenges associated with our research. This paper will likely be of interest to educators and researchers who are involved with developing and/or evaluating ethical capabilities among engineering students. 
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  7. We present our experimental results on generating photon pairs entangled in a transverse-mode Bell state in few-mode optical fiber by controlling the transverse mode of the pump to selectively excite spontaneous four-wave mixing processes.

     
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