Cooperative origin of proton pair diffusivity in yttrium substituted barium zirconate

Abstract Proton conduction is an important property for fuel cell electrolytes. The search for molecular details on proton transport is an ongoing quest. Here, we show that in hydrated yttrium doped barium zirconate using X-ray and neutron diffraction that protons tend to localize near the dopant yttrium as a conjugated superstructure. The proton jump time measured using quasi-elastic neutron scattering follows the Holstein-Samgin polaron model, revealing that proton hopping is weakly coupled to the high-frequency O-H stretching motion, but strongly coupled to low-frequency lattice phonons. The ratio of the proton polaron effective mass, m*, and the proton mass is m*/m = 2, when coupled to the Zr-O stretching mode, giving experimental evidence of proton pairing in perovskites, as a result of proton-phonon coupling. Possible pathways of a proton pair are provided through Nudge Elastic Band calculations. The pairing of protons, when jumping, is discussed in context of a cooperative protonic charge transport process.

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CFT unitarity and the AdS Cutkosky rules

Journal of High Energy Physics ◽

10.1007/jhep11(2020)073 ◽

2020 ◽

Vol 2020 (11) ◽

Author(s):

David Meltzer ◽

Allic Sivaramakrishnan

Keyword(s):

Flat Space ◽

Tree Level ◽

Optical Theorem ◽

Conformal Field Theories ◽

Strongly Coupled ◽

Conformal Field ◽

Weakly Coupled ◽

S Matrix ◽

Space Limit ◽

Diagrammatic Method

Abstract We derive the Cutkosky rules for conformal field theories (CFTs) at weak and strong coupling. These rules give a simple, diagrammatic method to compute the double-commutator that appears in the Lorentzian inversion formula. We first revisit weakly-coupled CFTs in flat space, where the cuts are performed on Feynman diagrams. We then generalize these rules to strongly-coupled holographic CFTs, where the cuts are performed on the Witten diagrams of the dual theory. In both cases, Cutkosky rules factorize loop diagrams into on-shell sub-diagrams and generalize the standard S-matrix cutting rules. These rules are naturally formulated and derived in Lorentzian momentum space, where the double-commutator is manifestly related to the CFT optical theorem. Finally, we study the AdS cutting rules in explicit examples at tree level and one loop. In these examples, we confirm that the rules are consistent with the OPE limit and that we recover the S-matrix optical theorem in the flat space limit. The AdS cutting rules and the CFT dispersion formula together form a holographic unitarity method to reconstruct Witten diagrams from their cuts.

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Prandtl Number in Classical Hard-Sphere and One-Component Plasma Fluids

Molecules ◽

10.3390/molecules26040821 ◽

2021 ◽

Vol 26 (4) ◽

pp. 821

Author(s):

Sergey Khrapak ◽

Alexey Khrapak

Keyword(s):

Prandtl Number ◽

Hard Sphere ◽

Solid Phase ◽

Freezing Point ◽

Three Dimensional ◽

Order Unity ◽

Strongly Coupled ◽

Dielectric Fluids ◽

Weakly Coupled ◽

Component Plasma

The Prandtl number is evaluated for the three-dimensional hard-sphere and one-component plasma fluids, from the dilute weakly coupled regime up to a dense strongly coupled regime near the fluid-solid phase transition. In both cases, numerical values of order unity are obtained. The Prandtl number increases on approaching the freezing point, where it reaches a quasi-universal value for simple dielectric fluids of about ≃1.7. Relations to two-dimensional fluids are briefly discussed.

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Modelling approach for low-frequency strongly coupled magnetic resonance wireless power transfer system

2016 Argentine Conference of Micro-Nanoelectronics, Technology and Applications (CAMTA) ◽

10.1109/camta.2016.7574084 ◽

2016 ◽

Cited By ~ 1

Author(s):

Agustin Rodriguez-Esteva ◽

Ma. Sofia Perez Casulo ◽

Bruno Serra Laborde ◽

Pablo Perez-Nicoli ◽

Fernando Silveira

Keyword(s):

Magnetic Resonance ◽

Low Frequency ◽

Wireless Power Transfer ◽

Transfer System ◽

Power Transfer ◽

Wireless Power ◽

Strongly Coupled ◽

Wireless Power Transfer System ◽

Modelling Approach

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Article

Canadian Journal of Chemistry ◽

10.1139/v99-157 ◽

1999 ◽

Vol 77 (11) ◽

pp. 1810-1812 ◽

Cited By ~ 7

Author(s):

Alex D Bain

Keyword(s):

Spin System ◽

Coupled System ◽

Coupled Systems ◽

Physical Reason ◽

Strongly Coupled ◽

System Combination ◽

First Order ◽

Weakly Coupled ◽

Quantum Transitions ◽

Weakly Coupled Systems

Strongly coupled spin systems provide many curious and interesting effects in NMR spectra, one of which is the presence of unexpected (from a first-order viewpoint) lines. A physical reason is given for the presence of these combination lines. The X part of the spectrum of an ABX spin system is analysed as an example. For an ABX system, it is well known that the AB nuclei give a spectrum consisting of two AB-type spectra, corresponding to the two orientations of the X nucleus. It can also be shown that the X part of the spectrum corresponds to the X nucleus undergoing a transition in the presence of an AB-like spin system. For weakly coupled systems, the four observed lines correspond to the four different orientations of the A and B nuclei. For a strongly coupled system, two additional lines may appear, the combination lines. The resulting six lines correspond to the four spin orientations, plus the two zero-quantum transitions. It is shown that these six lines are such that there is no net excitation of the AB-like spin system associated with the X transitions. There is no AB coherence created directly by a pulse applied to X. AB coherence is created as the system evolves, and this is responsible for many of the curious effects. This is shown to be true for all spin sub-systems, which are weakly coupled to a strongly coupled sub-system.Key words: NMR, strong coupling, second-order spectra, ABX spin system, combination lines, spectral analysis.

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Low-frequency sound sources in high-speed turbulent jets

Journal of Fluid Mechanics ◽

10.1017/s0022112008004096 ◽

2008 ◽

Vol 617 ◽

pp. 231-253 ◽

Cited By ~ 33

Author(s):

DANIEL J. BODONY ◽

SANJIVA K. LELE

Keyword(s):

High Speed ◽

Low Frequency ◽

Turbulent Jets ◽

Acoustic Analogy ◽

Sound Sources ◽

Strongly Coupled ◽

Eddy Simulation ◽

Phase Cancellation ◽

Jet Velocity ◽

Two Jets

An analysis of the sound radiated by three turbulent, high-speed jets is conducted using Lighthill's acoustic analogy (Proc. R. Soc. Lond. A, vol. 211, 1952, p. 564). Computed by large eddy simulation the three jets operate at different conditions: a Mach 0.9 cold jet, a Mach 2.0 cold jet and a Mach 1.0 heated jet. The last two jets have the same jet velocity and differ only by temperature. None of the jets exhibit Mach wave characteristics. For these jets the comparison between the Lighthill-predicted sound and the directly computed sound is favourable for all jets and for the two angles (30° and 90°, measured from the downstream jet axis) considered. The momentum (ρuiuj) and the so-called entropy [p − p∞ − a∞2(ρ − ρ∞)] contributions are examined in the acoustic far field. It is found that significant phase cancellation exists between the momentum and entropy components. It is observed that for high-speed jets one cannot consider ρuiuj and (p′ − a∞2ρ′)δij as independent sources. In particular the ρ′ūxūx component of ρuiuj is strongly coupled with the entropy term as a consequence of compressibility and the high jet velocity and not because of a linear sound-generation mechanism. Further, in more usefully decoupling the momentum and entropic contributions, the decomposition of Tij due to Lilley (Tech. Rep. AGARD CP-131 1974) is preferred. Connections are made between the present results and the quieting of high-speed jets with heating.

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A New Method for Displacement Analysis of Multi-Loop Spatial Linkages Based on Ordered Simple-Opened-Chains

Volume 2B: 24th Biennial Mechanisms Conference ◽

10.1115/96-detc/mech-1552 ◽

1996 ◽

Author(s):

Xian-Wen Kong ◽

Ting-Li Yang

Keyword(s):

Continuation Method ◽

The Other ◽

New Method ◽

New Approach ◽

Strongly Coupled ◽

Displacement Analysis ◽

Cpu Time ◽

Base Points ◽

Weakly Coupled ◽

Spatial Linkages

Abstract This paper presents systematically a new method for the displacement analysis (DA) of multi-loop spatial linkages (MLSLs) based on ordered simple-opened-chains (SOCs). In performing DA, a MLSL is converted into not a set of base points, a set of isolated links or a tree with/without isolated links in common use, but a weakly coupled MLSL in this paper. The characteristics of the proposed method are: (a) The number of unknowns in the set of equations for displacement analysis (EDA) of a MLSL is reduced to the minimum; (b) All the possible configurations corresponding to a given set of inputs of a weakly coupled MLSL or a strongly coupled MLSL with the coupled degree k = 1 can be obtained quickly. As compared with the other two methods available to find all the solutions to the DA in the case of MLSL with k = 1, the proposed method is superior to the resultant method in that it is applicable to more complex MLSLs and superior to the continuation method in that it takes much less CPU time to find all the solutions; (c) The set of EDA can be formulated and solved automatically; and (d) The new approach makes it possible to perform the kinematic and kineto-static analyses in a unified and simplified way.

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A Reusable 3D Printed Cavity Resonator for Liquid Sample Characterization

International Symposium on Microelectronics ◽

10.4071/2380-4505-2018.1.000389 ◽

2018 ◽

Vol 2018 (1) ◽

pp. 000389-000392

Author(s):

Saranraj Karuppuswami ◽

Saikat Mondal ◽

Mohd Ifwat Mohd Ghazali ◽

Premjeet Chahal

Keyword(s):

Dielectric Constant ◽

Cavity Resonator ◽

Dielectric Constants ◽

Sample Holder ◽

Strongly Coupled ◽

Weakly Coupled ◽

Sample Characterization ◽

3D Printed ◽

Standard Values ◽

High Dielectric

Abstract In this paper, additive manufacturing (3D printing) is used to fabricate and demonstrate a reusable microfluidic coupled rectangular cavity resonator for characterizing liquids in small volumes. The designed cavity operates in the fundamental TE101 mode and resonates at 4.12 GHz. The resonance of the cavity is perturbed by the sample placed in a small volume sample holder through a slot in the top cover. Two different perturbation configurations are investigated: i) strongly coupled (liquids with low to medium dielectric constants), and ii) weakly coupled (liquids with medium to high dielectric constant). The sample holder is loaded with different solvents and the shift in the resonance frequency is monitored. Based on these changes, the dielectric constant of the solvent is theoretically estimated and compared to standard values. The reusable liquid sensor holds significant potential in identifying and quantifying unknown liquid samples in the supply chain.

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Nonlinear matter terms in general scalar–tensor braneworld cosmology

International Journal of Modern Physics D ◽

10.1142/s0218271819501384 ◽

2019 ◽

Vol 28 (11) ◽

pp. 1950138

Author(s):

Kevin F. S. Pardede ◽

Agus Suroso ◽

Freddy P. Zen

Keyword(s):

Big Bang ◽

Accelerated Expansion ◽

Big Bang Nucleosynthesis ◽

Braneworld Cosmology ◽

Strongly Coupled ◽

Weakly Coupled ◽

General Scalar ◽

Bulk Scalar Field ◽

The Big Bang ◽

Correction Terms

A five-dimensional braneworld cosmological model in general scalar–tensor action that is comprised of various Horndeski Lagrangians is considered. The Friedmann equations in the case of strongly and weakly coupled [Formula: see text] Horndeski Lagrangians have been obtained. The strongly coupled [Formula: see text] model produces the Cardassian term [Formula: see text] with [Formula: see text], which can serve as an alternative explanation for the accelerated expansion phase of the universe. Furthermore, the latest combined observational facts from BAO, CMB, SNIa, [Formula: see text] and [Formula: see text] value observation suggest that the [Formula: see text] term lies quite close to the constrained value. On the other hand, the weakly coupled [Formula: see text] case has several new correction terms which are omitted in the braneworld Einstein–Hilbert model, e.g. the cubic [Formula: see text] and the dark radiation–matter interaction term [Formula: see text]. Furthermore, this model provides a cosmological constant constructed from the bulk scalar field, requires no brane tension and supports the big bang nucleosynthesis (BBN) constraint naturally.

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