A comparison of lithium-ion cell performance across three different cell formats

To investigate the influence of cell formats during a cell development programme, lithium-ion cells have been prepared in three different formats. Coin cells, single layer pouch cells, and stacked pouch cells gave a range of scales of almost three orders of magnitude. The cells used the same electrode coatings, electrolyte and separator. The performance of the different formats was compared in long term cycling tests and in measurements of resistance and discharge capacities at different rates. Some test results were common to all three formats. However, the stacked pouch cells had higher discharge capacities at higher rates. During cycling tests, there were indications of differences in the predominant degradation mechanism between the stacked cells and the other two cell formats. The stacked cells showed faster resistance increases, whereas the coin cells showed faster capacity loss. The difference in degradation mechanism can be linked to the different thermal and mechanical environments in the three cell formats. The correlation in the electrochemical performance between coin cells, single layer pouch cells, and stacked pouch cells shows that developments within a single cell format are likely to lead to improvements across all cell formats

Does predation control the diapausing stock of Calanus finmarchicus in the Gulf of Maine?

© The Author(s), 2022. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Wiebe, P., Baumgartner, M., Copley, N., Lawson, G., Davis, C., Ji, R., & Greene, C. Does predation control the diapausing stock of Calanus finmarchicus in the Gulf of Maine? Progress In Oceanography, 206, (2022): 102861, https://doi.org/10.1016/j.pocean.2022.102861.The variability of zooplankton populations is controlled by external and internal forcing, with the former being principally large-scale changes in circulation, and the latter being driven by in situ growth, competition, and predation. Assessing the relative importance of these forcings is challenging and requires analyses of multifaceted observational data. As part of the U.S. GLOBEC Georges Bank program, a series of cruises were conducted in fall 1997, 1998, and 1999 to survey diapausing populations of Calanus finmarchicus and their predators in Wilkinson, Jordan, and Georges Basins of the Gulf of Maine. Station and underway sampling were conducted using net (1 m2 MOCNESS) and bioacoustic (BIOMAPER-II) systems, respectively, to acquire vertically stratified data for zooplankton biomass, taxonomic, size, and life-stage composition, together with associated environmental data. The results show that the autumn diapausing C. finmarchicus abundance was much lower in 1998 than in 1997 or 1999, even though the overall zooplankton biomass levels were comparable between the three years. The size frequency distribution of the diapausing individuals had a bi-modal pattern in 1997 and 1999, but a single mode in 1998, indicating the demise of an early cohort of the diapausing stock. The relative biomass and computed energy demand of potential invertebrate predators (euphausiids, decapods, medusae, and siphonophores) was found to be higher in 1998 and could account for the missing C. finmarchicus cohort. Evidence collected from this study supports the hypothesis that local predation has the potential to control the diapausing stock of C. finmarchicus in the Gulf of Maine.RJ received support from the Northeast US Shelf Long Term Ecological Research (NES-LTER) project (NSF OCE-1655686) and the US MBON Gulf of Maine project to NERACOOS (NOPP award NA19NOS0120197 and BOEMUMaine Cooperative Agreement M19AC00022) for analyzing the size data and working on the manuscript. Research support was provided by the US GLOBEC Georges Bank Program through the CILER Cooperative Agreement NA-67RJO148 (NOAA Coastal Ocean Program)

SP742 Camphor Shot Borer: A New Nursery and Landscape Pest in Tennessee

Tennessee State University/UT Extension joint publicatio

Determining dominant scatterers of sound in mixed zooplankton populations

Author Posting. © Acoustical Society of America, 2007. This article is posted here by permission of Acoustical Society of America for personal use, not for redistribution. The definitive version was published in Journal of the Acoustical Society of America 122 (2007): 3304-3326, doi:10.1121/1.2793613.High-frequency acoustic scattering techniques have been used to investigate dominant scatterers in mixed zooplankton populations. Volume backscattering was measured in the Gulf of Maine at 43, 120, 200, and 420 kHz. Zooplankton composition and size were determined using net and video sampling techniques, and water properties were determined using conductivity, temperature, and depth sensors. Dominant scatterers have been identified using recently developed scattering models for zooplankton and microstructure. Microstructure generally did not contribute to the scattering. At certain locations, gas-bearing zooplankton, that account for a small fraction of the total abundance and biomass, dominated the scattering at all frequencies. At these locations, acoustically inferred size agreed well with size determined from the net samples. Significant differences between the acoustic, net, and video estimates of abundance for these zooplankton are most likely due to limitations of the net and video techniques. No other type of biological scatterer ever dominated the scattering at all frequencies. Copepods, fluid-like zooplankton that account for most of the abundance and biomass, dominated at select locations only at the highest frequencies. At these locations, acoustically inferred abundance agreed well with net and video estimates. A general approach for the difficult problem of interpreting high-frequency acoustic scattering in mixed zooplankton populations is described.This research was supported in part by the U.S. GLOBEC program, NOAA (Grant nos. NA17RJ1223 and NA67RJ0148), the James S. Cole and Cecily C. Selby Endowed Funds, the Penzance Endowed Fund for Support of Assistant Scientists, and the Adams Chair at the Woods Hole Oceanographic Institution. A selected number of focused experiments were also funded by the ONR (Grant No. N00014-98-1-0362)

Selecting hybrid pine clones for deployment - The pointy end of wood quality improvement

A clonal forestry research programme on Pinus elliottii Engelm. (slash pine) x P. caribaea Morelet var. hondurensis Barrett & Golfari (Caribbean pine) hybrids commenced in Queensland in 1986. Each cycle of clonal tests covered about 5 calendar years from field planting, and studies of wood quality variation have so far been used in selecting superior clones from the first three series of tests for commercial plantation deployment. Experience from the Series III clonal selection round is used to highlight the difficulties of ranking elite clones given a large number of growth, form, and wood property traits. Three to six ramets were felled from the best 32 clones in the Series III trials at age 6.8 years and a 3-m butt log from each was sawn into 70 × 35-mm structural boards. The clones sawn were ranked for routine deployment using data on growth, form, and wood traits. All recovered boards were assessed for distortion and tested for modulus of elasticity and modulus of rupture. Various non-destructive wood evaluation methods were used to estimate modulus of elasticity (wood stiffness) in these trees. Standing tree acoustic velocity assessed with an ST300 tool was slightly less strongly correlated phenotypically with the average modulus of elasticity of the recovered boards (r = 0.88**) than with predictions of modulus of elasticity from resonance vibration test samples and SilviScan estimates (both r = 0.89**). Moderate phenotypic relationships were found for individual tree means between average twist of the sawn boards and the average spiral grain angle of growth rings 2, 3, and 4 (r = 0.70**) assessed using a breast-height 12-mm increment core, and between average bow in the boards and average microfibril angle (r = 0.64**) from SilviScan assessments of core samples

Machine learning for investigating the relative importance of electrodes’ N:P areal capacity ratio in the manufacturing of lithium-ion battery cells

This work studies the impact of the ratio between the areal capacity of Graphite anode to NMC622 cathode for Lithium-ion batteries compared to the electrode characteristics of thickness, mass loading and cathode areal capacity, on their electrochemical properties. The influence of factors on energy capacity and gravimetric capacity at various Crates starting from C/20 up to 10C is quantified by combining experiments obtained via design of experiment techniques, machine learning modelling and explanation techniques. The results highlight that the performance at all Crates is highly affected by all features however their relative importance, and the linearity and nonlinearity of the dependencies is quite unique for each Crate capacity. N:P ratio is showing a relatively smaller effect on electrochemical performance compared to thickness, mass loading of active material and cathode areal capacity. It is also concluded that while the impact of N:P ratio is almost linear at lower Crates, it is nonlinear with a local optimum at medium and high Crates. This study offers a methodology for smart selection of a ratio between anode and cathode aerial capacity for a balanced performance of cells at all Crates

Cross-sectional analysis of lithium ion electrodes using spatial autocorrelation techniques

Join counting, a standard technique in spatial autocorrelation analysis, has been used to quantify the clustering of carbon, fluorine and sodium in cross-sectioned anode and cathode samples. The sample preparation and EDS mapping steps are sufficiently fast for every coating from two Design of Experiment (DoE) test matrices to be characterised. The results show two types of heterogeneity in material distribution; gradients across the coating from the current collector to the surface, and clustering. In the cathode samples, the carbon is more clustered than the fluorine, implying that the conductive carbon component is less well distributed than the binder. The results are correlated with input parameters systematically varied in the DoE e.g. coating blade gap, coating speed, and other output parameters e.g. coat weight, and electrochemical resistance

Patient experiences with oily skin: The qualitative development of content for two new patient reported outcome questionnaires

<p>Abstract</p> <p>Objective</p> <p>To develop the content for two new patient reported outcome (PRO) measures to: a) assess the severity of symptoms; and b) the impact of facial skin oiliness on emotional wellbeing using qualitative data from face to face, and internet focus groups in Germany and the US.</p> <p>Methods</p> <p>Using input from initial treatment satisfaction focus groups (n = 42), a review of relevant literature and expert clinicians (n = 3), a discussion guide was developed to guide qualitative inquiry using Internet focus groups (IFGs). IFGs were conducted with German (n = 26) and US (n = 28) sufferers of oily skin. Questionnaire items were generated using coded transcript data from the focus groups. Cognitive debriefing was conducted online with 42 participants and face to face with an additional five participants to assess the comprehension of the items.</p> <p>Results</p> <p>There were equal numbers of male and female participants; mean age was 35.4 (SD 9.3) years. On average, participants had had oily skin for 15.2 years, and 74% (n = 40) reported having mild-moderate acne. Participants reported using visual, tactile and sensory (feel without touching their face) methods to evaluate the severity of facial oiliness. Oily facial skin had both an emotional and social impact, and was associated with feelings of unattractiveness, self-consciousness, embarrassment, irritation and frustration. Items were generated for a measure of oily skin severity (Oily Skin Self-Assessment Scale) and a measure of the impact of oily skin on emotional well-being (Oily Skin Impact Scale). Cognitive debriefing resulted in minor changes to the draft items and confirmed their face and content validity.</p> <p>Conclusion</p> <p>The research provides insight into the experience of having oily skin and illustrates significant difficulties associated with the condition. Item content was developed for early versions of two PRO measures of the symptoms and emotional impact of oily facial skin. The psychometric validation of these measures reported elsewhere.</p