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The crystallization of poly(ethylene-vinyl acetate) and linear low-density polyethylene (LLDPE) films spun-cast from the polymer/toluene solutions with as-cast thickness from 460 to 10 nm was studied. The lamellar thickness was measured using small-angle X-ray scattering (SAXS) and found to increase from 14 to 21 nm for films thinner than 100 nm. The morphology of LLDPE measured by scanning probe microscopy (SPM) showed an edge-on lamellae for the films thicker than 30 nm and flaton lamellae for the films thinner than 15 nm. A pseudo-"shish-kebab" tiny crystal structure was observed in between the larger lamellae. Crystallinity was confirmed using attenuated total reflectance-Fourier transformed infrared spectroscopy (ATR-FTIR) and near-edge X-ray absorption fine structure (NEXAFS) spectroscopy. The shear modulation force microscopy technique (SMFM) was used to measure the melting point, T m, which was found to decrease for films thinner than 100 nm. The rate of decrease was a function of the annealing protocol, but in all cases for films approximately 20 nm thick Tm was depressed by 35-40 °C. This large value cannot be predicted from the classical Gibbs-Thomson relation, unless a change in the effective heat of fusion is assumed due to surface interactions.

We present three STEVE (strong thermal emission velocity enhancement) events in conjunction with Time History of Events and Macroscale Interactions (THEMIS) in the magnetosphere and Defense Meteorological Satellite Program (DMSP) and Swarm in the ionosphere, for determining equatorial and interhemispheric signatures of the STEVE purple/mauve arc and picket fence. Both types of STEVE emissions are associated with subauroral ion drifts (SAID), electron heating, and plasma waves. The magnetosphere observations show structured electrons and flows and waves (likely kinetic Alfven, magnetosonic, or lower‐hybrid waves) just outside the plasmasphere. Interestingly, the event with the picket fence had a >~1 keV electron structure detached from the electron plasma sheet, upward field‐aligned currents (FACs), and ultraviolet emissions in the conjugate hemisphere, while the event with only the mauve arc did not have precipitation or ultraviolet emission. We suggest that the electron precipitation drives the picket fence, and heating drives the mauve as thermal emission.

A consistent and accurate ab initio parametrization of density functional dispersion correction (DFT-D) for the 94 elements H

Strong dependence of the crystal orientation, morphology, and melting temperature (Tm) on the substrate is observed in the semicrystalline polyethylene thin films. The Tm decreases with the film thickness decrease when the film is thinner than a certain critical thickness, and the magnitude of the depression increases with increasing surface interaction. We attribute the large Tm depression to the decrease in the overall free energy on melting, which is caused by the substrate attraction force to the chains that competes against the interchain force which drives the chains to crystallization.

This paper reviews our current understanding of auroral features that appear poleward of the main auroral oval within the polar cap, especially those that are known as Sunaligned arcs, transpolar arcs, or theta auroras. They tend to appear predominantly during periods of quiet geomagnetic activity or northwards directed interplanetary magnetic field (IMF). We also introduce polar rain aurora which has been considered as a phenomenon on open field lines. We describe the morphology of such auroras, their development and Auroral Physics Edited by 15 Page 2 of 44 K. Hosokawa et al.dynamics in response to solar wind-magnetosphere coupling processes, and the models that have been developed to explain them.

We present unique coordinated observations of the dayside auroral oval, polar cap, and nightside auroral oval by three all-sky imagers, two Super Dual Auroral Radar Network (SuperDARN) radars, and Defense Meteorological Satellite Program (DMSP)-17. This data set revealed that a dayside poleward moving auroral form (PMAF) evolved into a polar cap airglow patch that propagated across the polar cap and then nightside poleward boundary intensifications (PBIs). SuperDARN observations detected fast antisunward flows associated with the PMAF, and the DMSP satellite, whose conjunction occurred within a few minutes after the PMAF initiation, measured enhanced low-latitude boundary layer precipitation and enhanced plasma density with a strong antisunward flow burst. The polar cap patch was spatially and temporally coincident with a localized antisunward flow channel. The propagation across the polar cap and the subsequent PBIs suggests that the flow channel originated from dayside reconnection and then reached the nightside open-closed boundary, triggering localized nightside reconnection and flow bursts within the plasma sheet.

We present high-resolution C 1s and O 1s photoemission results of different NTCDA monolayer states adsorbed on a Ag(111) substrate (NTCDA ) 1,4,5,8-naphthalene-tetracarboxylic acid dianhydride). The comparison of mono-and multilayer data clearly proves the chemisorptive character of the bonding of this planar aromatic molecule to the metal substrate. The rich fine structures of the monolayer spectra exhibit large differences for the three distinct monolayer states observed, leading to the conclusion of significant differences in their bonding. The fine structures are interpreted in detail on the basis of a thorough peak-fit analysis which allows a consistent assignment of the various photoemission main and satellite lines. As a result, the binding energies of the 1s levels of all C and O atoms and the relative intensities of the most significant satellite lines are extracted, the latter providing important information on the bonding and the dynamic screening process.