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Results for “circularity”
Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Toward Circular Recycling of Polyurethanes: Depolymerization and Recovery of Isocyanates
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Circular-polarization-selective perfect reflection from chiral superconductors
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A circular polyester platform based on simple gem-disubstituted valerolactones
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Circular dichroism in non-chiral metal halide perovskites
Non-chiral orthorhombic perovskite nanostructures can exhibit chiro-optic effects under off-normal illumination due to the Rashba effect.
Regulating the stereomicrostructure, circularity and functionality of synthetic PHAs
Synthetic poly(3-hydroxyalkanoate)s are empowered by catalyst-controlled stereomicrostructures, monomer-designed melt-processability and chemical recyclability, and pendant-group-regulated functionalities.
Recommendations for life-cycle assessment of recyclable plastics in a circular economy
Life-cycle assessment can better capture the impacts of plastics recycling by expanding beyond greenhouse gases to include fossil carbon balances, net diversion of waste from landfill, and avoided release of plastic pollution to the environment.
Chiral population analysis: a real space visualization of X-ray circular dichroism
The microscopic understanding of probing and controlling molecular chirality is of considerable interest. Numerous spectroscopic techniques are capable of monitoring molecular asymmetry and its consequences, ranging from the infrared to the X-ray regime. Resonant X-rays have long been used to investigate local atomic sites within molecules thanks to the localized nature of core electronic transitions. These techniques can be used to determine the extent to which chirality is a local versus a delocalized property. However, how to systematically partition dichroic contributions from the point of view of electronic structure simulations remains an open question. Here, we introduce the concept of chiral population analysis that connects chirality to the atomic orbital picture. In analogy with Mulliken population analysis, which assigns charges to atomic orbitals, chiral populations allow the dichroic response to be distributed among the participating atomic orbitals. This decomposition can be further visualized in real space by representing it in terms of isosurface plots, providing an intuitive way to connect the dichroic response to its origins. Thus chiral population analysis can be particularly useful to assess the extent to which a given electronic transition is sensitive to chirality as a local or global feature of the molecular geometry.
Multi-layering of SU-8 exhibits distinct geometrical transitions from circular to planarized profiles
The negative tone photoresist SU-8 permits the creation of micrometer-scale structures by optical lithography. It is also the most used photoresist in soft lithography for the fast-prototyping of microfluidic devices. Despite its importance, the effect of capillary forces on SU-8 multi-layering onto topographical features has not been thoroughly studied. In particular, the profile of the added layer has not been examined in detail. The overlaying process exhibits a set of distinct behaviors, or regimes, depending on the relative thickness of the overlay and the underlying rectangular pattern. We demonstrate how capillary effects control the profile of multi-layer microchannels in a predictable manner. We derive a simple static model to describe the evolution of the overlay as a function of dimensionless geometric parameters. Our study provides a critical understanding of the parameters that govern multi-layer spin coating.
Generation of a quasi-static magnetic field by a circularly polarised laser pulse due to tunnelling gas ionisation
We present a theoretical model of the quasi-static magnetic field generation in a laser channel, which is formed behind the front of a short laser pulse that ionises a gas. The generation of a magnetic field is caused by the appearance of the electron pressure anisotropy during tunnelling ionisation of atoms. In the considered case of subrelativistic laser light intensities, the generated magnetic field can reach ∼1 MG with an energy transformation ratio of about 1 %, which paves the way for identifying the proposed mechanism when use is made of a wide class of ultrashort pulse lasers. (interaction of laser radiation with matter. laser plasma)
Interferometric circular dichroism in photoelectron momentum distributions
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Circular attractors as heating mechanism in coherent electron cooling
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Experimental studies of circular attractors in the first rf-based electron cooler
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Giant intrinsic circular dichroism of enantiomorphic flat Chern bands and flatband devices
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Topological resonance in Weyl semimetals in a circularly polarized optical pulse
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Photon correlation spectroscopy with heterodyne mixing based on soft x-ray magnetic circular dichroism
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