914 research outputs found
Fatigue Behavior of a Cross-Ply Ceramic Matrix Composite at Elevated Temperature under Tension-Tension Loading
This study investigated the fatigue behavior and damage mechanisms of a [0-90]4s SiC-MAS ceramic matrix composite under tension-tension loading at two elevated temperatures and two frequencies. Stress and strain hystereses, maximum and minimum strain, and modulus of elasticity were evaluated to characterize the material behavior. Microscopy and fractography were used to evaluate damage progression and mechanisms. Fatigue life was independent of frequency at both temperatures
Matching-stimulus-interval affects the N2 and the P3: a principal components analysis
Abstract presented at the 23rd Australasian Society for Psychophysiology Conference, 20-22 Nov 2013, Wollongong, Australi
Sequential Processing and the Matching-Stimulus Interval Effect in ERP Components: An Exploration of the Mechanism Using Multiple Regression
In oddball tasks, increasing the time between stimuli within a particular condition (target-to-target interval, TTI; nontarget-to-nontarget interval, NNI) systematically enhances N1, P2, and P300 event-related potential (ERP) component amplitudes. This study examined the mechanism underpinning these effects in ERP components recorded from 28 adults who completed a conventional three-tone oddball task. Bivariate correlations, partial correlations and multiple regression explored component changes due to preceding ERP component amplitudes and intervals found within the stimulus series, rather than constraining the task with experimentally constructed intervals, which has been adequately explored in prior studies. Multiple regression showed that for targets, N1 and TTI predicted N2, TTI predicted P3a and P3b, and Processing Negativity (PN), P3b, and TTI predicted reaction time. For rare nontargets, P1 predicted N1, NNI predicted N2, and N1 predicted Slow Wave (SW). Findings show that the mechanism is operating on separate stages of stimulus-processing, suggestive of either increased activation within a number of stimulus-specific pathways, or very long component generator recovery cycles. These results demonstrate the extent to which matching-stimulus intervals influence ERP component amplitudes and behavior in a three-tone oddball task, and should be taken into account when designing similar studies
1980 Missouri commercial strawberry spray schedule
"MP 266, 1/80, 1.5M
Polyanionic Ligand Platforms for Methyl- and Dimethylaluminum Arrays
Trimethylaluminum
finds widespread applications in chemical and materials synthesis,
most prominently in its partially hydrolyzed form of methylalumoxane
(MAO), which is used as a cocatalyst in the polymerization of olefins.
This work investigates the sequential reactions of trimethylaluminum
with hexaprotic phosphazenes (RNH)6P3N3 (=XH6) equipped with substituents R of varied
steric bulk including tert-butyl (1H6), cyclohexyl (2H6), isopropyl (3H6), isobutyl (4H6), ethyl
(5H6), propyl (6H6), methyl (7H6), and benzyl (8H6). Similar to MAO, the resulting complexes of polyanionic
phosphazenates [XHn]n−6 accommodate multinuclear arrays
of [AlMe2]+ and [AlMe]2+. Reactions
were monitored by 31P NMR spectroscopy, and structures
were determined by single-crystal X-ray diffraction. They included 1H4(AlMe2)2, 1H3(AlMe2)3, 2H3(AlMe2)3, 3(AlMe2)4AlMe, 4HÂ(AlMe2)5, 4(AlMe2)6, {5HÂ(AlMe2)4}2AlMe, 5(AlMe2)6, 6(AlMe2)6, {7(AlMe2)4AlMe}2, and 8(AlMe2)6. The study shows that subtle
variations of the steric properties of the R groups influence the
reaction pathways, levels of aggregation, and fluxional behavior.
While [AlMe2]+ is the primary product of the
metalation, [AlMe]2+ is utilized to alleviate overcrowding
or to aid aggregation. At the later stages of metalation, [AlMe2]+ groups start to scramble around congested sites.
The ligands proved to be very robust and extremely flexible, offering
a unique platform to study complex multinuclear metal arrangements
1975 commercial grape spray schedule
"MP 263, 2/75/1.5M"PRE-BLOOM SPRAYS -- BLOOM SPRAYS -- POST-BLOOM SPRAYS -- SUMMER SPRAYSBy W.R. Enns and W.S. Craig (Department of Entomology), A.E. Gaus (Department of Horticulture) and P.W. Steiner, H.W. Shaffer, and E.W. Palm (Department of Plant Pathology
From Forbidden Coronal Lines to Meaningful Coronal Magnetic Fields
We review methods to measure magnetic fields within the corona using the
polarized light in magnetic-dipole (M1) lines. We are particularly interested
in both the global magnetic-field evolution over a solar cycle, and the local
storage of magnetic free energy within coronal plasmas. We address commonly
held skepticisms concerning angular ambiguities and line-of-sight confusion. We
argue that ambiguities are in principle no worse than more familiar remotely
sensed photospheric vector-fields, and that the diagnosis of M1 line data would
benefit from simultaneous observations of EUV lines. Based on calculations and
data from eclipses, we discuss the most promising lines and different
approaches that might be used. We point to the S-like [Fe {\sc XI}] line (J=2
to J=1) at 789.2nm as a prime target line (for ATST for example) to augment the
hotter 1074.7 and 1079.8 nm Si-like lines of [Fe {\sc XIII}] currently observed
by the Coronal Multi-channel Polarimeter (CoMP). Significant breakthroughs will
be made possible with the new generation of coronagraphs, in three distinct
ways: (i) through single point inversions (which encompasses also the analysis
of MHD wave modes), (ii) using direct comparisons of synthetic MHD or
force-free models with polarization data, and (iii) using tomographic
techniques.Comment: Accepted by Solar Physics, April 201
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