Characterisation of terrestrial weathering products in ordinary and CM carbonaceous chondrites

Research investigating the terrestrial weathering experienced by ordinary and CM chondrites at high spatial resolution is sparse, with most published work using either bulk mineralogical or chemical analysis techniques. With asteroid sample return missions, Hayabusa 2 and OSIRIS-REx expected to return samples in near future, understanding the effects of terrestrial contamination and weathering in fine detail is of paramount importance. The research presented here sets out to investigate terrestrial weathering by analysing the alteration products found around Fe,Ni metal grains by coupled chemical and mineralogical analysis for the first time. Analysis is conducted using a suite of high spatial resolution imaging and spectroscopic techniques including EDS spectroscopy and Raman spectroscopy, an approach with very limited previous use in this field. Initially characterisation of the effects of terrestrial weathering on ordinary chondrites, which should have only experienced significant aqueous alteration in the terrestrial environment, is conducted. The effects of weathering in three climates (the Antarctic, Sahara and Western Australia) are investigated to compare the intensity of alteration between typical find environments. The results of ordinary chondrite analysis reveal Cl-bearing akaganeite is the first terrestrial alteration product to form, followed by goethite and a poorly crystallised hydrated iron III oxide or oxyhydroxide. Analysis also reveals that terrestrial weathering was least intense in cold desert environments (Antarctica) and most intense in semi-arid environments (Western Australia). Having characterised the terrestrial weathering products which form around Fe,Ni metal the effects of terrestrial weathering on CM chondrites, which have experienced significant aqueous alteration both terrestrially and on their parent bodies, is investigated. Analysis of the weathering products in CM chondrites revealed the terrestrial alteration products akaganeite and goethite eroding/replacing parent body alteration products tochilinite and magnetite. The work presented here highlights the need for high resolution, chemical and mineralogical analysis of the alteration products found in ordinary and CM chondrites in order to prevent misinterpretation of terrestrially derived alteration products as evidence of parent body alteration

Development of Ferromagnetic Metallic Glasses into Low Loss Power Transformer Cores

Currently, 3% of energy losses in the U.S. electrical grid occur at power transformers. With a transition to Metglas, transformer efficiency could be increased, but is Metglas the best replacement material for power transformers? With this in mind we develop a Fe-based metallic glass for its glass forming ability and soft magnetic properties. During this development we identify a redox reaction of boron oxide by Si during melt fluxing of the Fe-based glass, which promotes an unexpected exchange of Si and B in the alloy. Taking this reaction into account, a unique optimization strategy is implemented, enabling oxide purification of the melt coupled with a significant but predictable shift in composition. This leads to an optimized Fe-based glass demonstrating a global peak in glass forming ability. Following boron oxide fluxing in the high temperature melt, alloy with composition Fe57.5Co20.2Si10.2B2.05P10.05 transforms to Fe57Co19.2Si6.8B7.4P9.6, and increases its critical rod diameter from 1 mm to 5 mm. The alloy also demonstrates excellent soft ferromagnetic performance characterized by a magnetic saturation of 1.53 T. While developing the above alloy, we also analyzed the effect of varying thickness of a Fe68Mo4Ni3Co5Si1P11.5C5B2.5 transformer core as a function of frequency to discover if there was a minimum in the losses. We did not find a single minimum, but found that the optimal thickness exhibits a logarithmic dependency on frequency. This dependence suggests the optimal thickness of a core ranges from 100−400μm, instead of in the &lt; 50μm range currently used. These larger optimal thicknesses are unexpected if anomalous losses are not considered, but the dominance of the anomalous losses at low frequencies, or for thin samples, validates the need for thicker power transformers. While other amorphous metals and casting techniques will yield varying results, the logarithmic dependence on frequency and the 100−400μm optimal thickness range should be broadly applicable.</p

[Memo to Sarah Lawrence Community from President Alice Ilchman, et al, March 1, 1989]

Memo describes an incident on campus surrounding a mural. It also outlines actions taken by College officials regarding the involved and concerned students as well as reaffirming the College\u27s core principles.https://digitalcommons.slc.edu/protest/1015/thumbnail.jp

Public Engagement with Research and Scholarship Evaluation Framework 2023-2028

In 2018, we, the School of Life Sciences Public Engagement team, worked with Evaluation Support Scotland to create an evaluation strategy aligned to our then recently developed Public Engagement with Research Strategy. The result was ‘OurEvaluation Story’ - an evaluation framework .Over the past 5 years, we used the framework to evaluate public engagement work. Starting in 2018, we produced an annual report to look in detail at what we were doing and if it helped the School of Life Sciences community achieve our ‘indicators of success’. Five years on, we have a strong collection of evidence to show how we have achieved some of our aims and objectives and where more work is needed.We revisited the evaluation strategy, with three key questions in mind:• What changes need to be made following its use and review?• Do the outcomes reflect the revised Public Engagement with Research and Scholarship Strategy?• Is the evaluation strategy the best it can be to help measure the impact of the Public Engagement with Research and Scholarship Strategy?This document contains our new evaluation framework and recording forms

Psychological effects of proper scoring rules

Proper scoring rules (PSRs) have been derived to elicit good probability assessments. Because there are so many different kinds of PSRs, this experiment was designed to determine if any particular characteristics contribute to effectiveness. Subjects observed poker chips in jars and bet on the color of the chip to be sampled. On different trials, lists of bets were generated by different PSRs. The type (log, quadratic, or spherical) of PSR used appeared to have essentially no effect on the probability inferred from the bet selected. However, the inferred probability became less extreme with increased steepness in the functions relating score to assessed probability. Also, various suboptimal strategies seemed to be employed when the rule contained both positive and negative scores, so all possible scores should probably be either positive or negative but not both.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/33909/1/0000174.pd