416 research outputs found
Domain and stripe formation between hexagonal and square ordered fillings of colloidal particles on periodic pinning substrates
Using large scale numerical simulations, we examine the ordering of colloidal particles on square periodic
two-dimensional muffin-tin substrates consisting of a flat surface with localized pinning sites. We show
that when there are four particles per pinning site, the particles adopt a hexagonal ordering, while for
five particles per pinning site, a square ordering appears. For fillings between four and five particles per
pinning site, we identify a rich variety of distinct ordering regimes, including disordered grain
boundaries, crystalline stripe structures, superlattice orderings, and disordered patchy arrangements. We
characterize the different regimes using Voronoi analysis, energy dispersion, and ordering of the
domains. We show that many of the boundary formation features we observe occur for a wide range of
other fillings. Our results demonstrate that grain boundary tailoring can be achieved with muffin-tin
periodic pinning substrates
Low velocity opposed-flow frame spread in a transport-controlled environment DARTFire
The overall objectives of the DARTFire project are to uncover the underlying physics and increase understanding of the mechanisms that cause flames to propagate over solid fuels against a low velocity of oxidizer flow in a low-gravity environment. Specific objectives are (1) to analyze experimentally observed flame shapes, measured gas-phase field variables, spread rates, radiative characteristics, and solid-phase regression rates for comparison with previously developed model prediction capability that will be continually extended, and (2) to investigate the transition from ignition to either flame propagation or extinction in order to determine the characteristics of those environments that lead to flame evolution. To meet the objectives, a series of sounding rocket experiments has been designed to exercise several of the dimensional, controllable variables that affect the flame spread process over PMMA in microgravity, i.e., the opposing flow velocity (1-20 cm/s), the external radiant flux directed to the fuel surface (0-2 W/cm(exp 2)), and the oxygen concentration of the environment (35-70%). Because radiative heat transfer is critical to these microgravity flame spread experiments, radiant heating is imposed, and radiant heat loss will be measured. These are the first attempts at such an experimental control and measurement in microgravity. Other firsts associated with the experiment are (1) the control of the low velocity, opposed flow, which is of the same order as diffusive velocities and Stefan flows; (2) state-of-the-art quantitative flame imaging for species-specific emissions (both infrared and ultraviolet) in addition to novel intensified array imaging to obtain a color image of the very dim, low-gravity flames
Wheat streak mosaic, High Plains disease, and Triticum mosaic: Three virus diseases of wheat in Oklahoma
The Oklahoma Cooperative Extension Service periodically issues revisions to its publications. The most current edition is made available. For access to an earlier edition, if available for this title, please contact the Oklahoma State University Library Archives by email at [email protected] or by phone at 405-744-6311
2010 YCAP Needs Assessment Report
This report outlines the Yamhill Community Action Partnership (YCAP) areas of need, strength, and improvement. Low income and unemployed individuals receive significant support through YCAP programs, including transportation, housing, and bill pay assistance. YCAP programs were assessed during the spring of 2010 through a client survey
Reproducibility of ambulatory blood pressure changes from the initial values on two different days
OBJECTIVE: We tested the reproducibility of changes in the ambulatory blood pressure (BP) from the initial values, an indicator of BP reactivity and cardiovascular health outcomes, in young, healthy adults. METHOD: The subjects wore an ambulatory BP monitor attached by the same investigator at the same time of day until the next morning on two different days (day 1 and day 2) separated by a week. We compared the ambulatory BP change from the initial values at hourly intervals over 24 waking and sleeping hours on days 1 and 2 using linear regression and repeated measures analysis of covariance. RESULTS: The subjects comprised 88 men and 57 women (mean age±SE 22.4±0.3 years) with normal BP (118.3±0.9/69.7±0.6 mmHg). For the total sample, the correlation between the ambulatory BP change on day 1 vs. day 2 over 24, waking, and sleeping hours ranged from 0.37-0.61; among women, the correlation was 0.38-0.71, and among men, it was 0.24-0.52. Among women, the ambulatory systolic/diastolic BP change was greater by 3.1±1.0/2.4±0.8 mmHg over 24 hours and by 3.0±1.1/2.4±0.8 mmHg over waking hours on day 1 than on day 2. The diastolic ambulatory BP change during sleeping hours was greater by 2.2±0.9 mmHg on day 1 than on day 2, but the systolic ambulatory BP change during sleeping hours on days 1 and 2 did not differ. Among men, the ambulatory BP change on days 1 and 2 did not differ. CONCLUSION: Our primary findings were that the ambulatory BP change from the initial values was moderately reproducible; however, it was more reproducible in men than in women. These results suggest that women, but not men, may experience an alerting reaction to initially wearing the ambulatory BP monitor
Banner News
https://openspace.dmacc.edu/banner_news/1416/thumbnail.jp
- …