NMR investigation of contextuality in a quantum harmonic oscillator via pseudospin mapping

Physical potentials are routinely approximated to harmonic potentials so as to analytically solve the system dynamics. Often it is important to know when a quantum harmonic oscillator (QHO) behaves quantum mechanically and when classically. Recently Su et. al. [Phys. Rev. A {\bf 85}, 052126 (2012)] have theoretically shown that QHO exhibits quantum contextuality (QC) for a certain set of pseudospin observables. In this work, we encode the four eigenstates of a QHO onto four Zeeman product states of a pair of spin-1/2 nuclei. Using the techniques of NMR quantum information processing, we then demonstrate the violation of a state-dependent inequality arising from the noncontextual hidden variable model, under specific experimental arrangements. We also experimentally demonstrate the violation of a state-independent inequality by thermal equilibrium states of nuclear spins, thereby assessing their quantumness.Comment: 5 Pages, 3 Figures, context dependency illustrated, error below eq. 5 correcte

Scaling up graphene PET nano-composites for industry applications

Graphene nanocomposites have offered promise to benefit manufactured goods and their packaging materials for over a decade. The promise includes improving thermal properties for processing, increased specific strength, enhanced barrier properties, and electrical conductivity. Often such improvements have a potential for implementation with very little change in industry standard processing equipment. As commodity and energy costs rise, efficient product design becomes increasingly important. Shipping and material costs have risen to a larger, and often leading, fraction of manufacturer’s total costs. Simply using less material means less weight, which both reduces raw material and transportation costs. However, this is only possible if the new design performance meets or exceeds market needs. An additional benefit of material reduction is a reduced impact on the environment. Some specific examples of environmental impact reduction from the use of graphene based nanocomposites were recently measured at 30%. In that case, the thermal properties provided the most significant benefit, allowing processing using less energy. There also appears to be benefit in recycling graphene-PET nano-composites over other additives in the recycle stream. Mechanical property enhancement from graphene nanocomposites remains the most important benefit for manufacturing. The promise of graphene nanocomposites to provide the lightweight high performance alternative to 20th century materials still stands. However, adaptation of nanocomposites in day-to-day applications outside the laboratory at industrial scale are lagging due to limitations with dispersing the nano-phase. A new approach of dosing nano-phase materials dispersed in a liquid medium during industry compatible molding processes can deliver the intended level of property improvements. This new method and resulting property improvements are discussed with examples including: improved thermal conductivity from graphene dispersed through melt mixing and liquid dosing; exfoliated graphene obtained through liquid dispersion improving the elastic modulus without impacting film clarity; and methods to track dosing consistency or quantifying dispersion level. These all indicate an effective exfoliation fraction exists which improves the composite properties

PET – A semi-crystalline nanocomposite

Polymer nanocomposites sparked significant interest due to unprecedented material properties and property combinations. While most polymer nanocomposites are multi-phase materials with distinctive chemical structure for each phase, it is possible to make a reinforcement with the same chemistry. Such composites have been demonstrated in metals and polymers. Reinforcement with the same base chemistry (self-reinforcing) has advantages in compatibility, load transfer, and processing ability. Composite research continues on interface properties and their optimization. This is often complicated by poor surface chemistry interactions. Polyethylene terephthalate (PET), a widely known semi-crystalline polymer, possess a unique micro-structure that can be engineered through process history. Bi-axial stretching near the glass transition temperature yields a semi-crystalline microstructure in PET controlled by a function of temperature and strain rate where, in many cases, the crystalline phase can be kept small and acts as a nano-scale reinforcement. Please click Additional Files below to see the full abstract

Computational Study of a Generic T-tail Transport

This paper presents a computational study on the static and dynamic stability characteristics of a generic transport T-tail configuration under a NASA research program to improve stall models for civil transports. The NASA Tetrahedral Unstructured Software System (TetrUSS) was used to obtain both static and periodic dynamic solutions at low speed conditions for three Reynolds number conditions up to 60 deg angle of attack. The computational results are compared to experimental data. The dominant effects of Reynolds number for the static conditions were found to occur in the stall region. The pitch and roll damping coefficients compared well to experimental results up to up to 40 deg angle of attack whereas yaw damping coefficient agreed only up to 20 deg angle of attack