General principles for describing electronic and proton multiple scattering processes in solids

Abstract Analytical solution for the reflected light ions Pass Length Distribution Function (PLDF) equation is obtained. Reflected ions energy spectra calculated on the basis of the developed method shows satisfactory agreement with experimental data. The effectiveness of the developed methodology in the procedure for verifying the stopping power value is indicated.

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Experimental demonstration of negative refraction with 3D locally resonant acoustic metafluids

Scientific Reports ◽

10.1038/s41598-021-84018-x ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Benoit Tallon ◽

Artem Kovalenko ◽

Olivier Poncelet ◽

Christophe Aristégui ◽

Olivier Mondain-Monval ◽

...

Keyword(s):

Experimental Data ◽

Yield Stress ◽

Multiple Scattering ◽

Silicone Rubber ◽

Acoustic Waves ◽

Scattering Theory ◽

Negative Refraction ◽

Volume Fraction ◽

Experimental Demonstration ◽

Acoustic Beam

AbstractNegative refraction of acoustic waves is demonstrated through underwater experiments conducted at ultrasonic frequencies on a 3D locally resonant acoustic metafluid made of soft porous silicone-rubber micro-beads suspended in a yield-stress fluid. By measuring the refracted angle of the acoustic beam transmitted through this metafluid shaped as a prism, we determine the acoustic index to water according to Snell’s law. These experimental data are then compared with an excellent agreement to calculations performed in the framework of Multiple Scattering Theory showing that the emergence of negative refraction depends on the volume fraction $$\Phi$$ Φ of the resonant micro-beads. For diluted metafluid ($$\Phi =3\%$$ Φ = 3 % ), only positive refraction occurs whereas negative refraction is demonstrated over a broad frequency band with concentrated metafluid ($$\Phi =17\%$$ Φ = 17 % ).

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Analytical solution of the PELDOR inverse problem using the integral Mellin transform

Physical Chemistry Chemical Physics ◽

10.1039/c7cp04059h ◽

2017 ◽

Vol 19 (48) ◽

pp. 32381-32388 ◽

Cited By ~ 5

Author(s):

Anna G. Matveeva ◽

Vyacheslav M. Nekrasov ◽

Alexander G. Maryasov

Keyword(s):

Inverse Problem ◽

Distribution Function ◽

Analytical Solution ◽

Short Distance ◽

Mellin Transform ◽

Distance Distribution ◽

Distance Distribution Function ◽

Distance Range ◽

Model Free ◽

Model Free Approach

The model-free approach used does not introduce systematic distortions in the computed distance distribution function between two spins and appears to result in noise grouping in the short distance range.

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SEMIEMPIRICAL SCF–LCAO–MO TREATMENT OF THIOPHENE, FURAN, AND PYRROLE

Canadian Journal of Chemistry ◽

10.1139/v65-208 ◽

1965 ◽

Vol 43 (5) ◽

pp. 1569-1576 ◽

Cited By ~ 61

Author(s):

N. Solony ◽

F. W. Birss ◽

John B. Greenshields

Keyword(s):

Experimental Data ◽

Satisfactory Agreement ◽

Electronic Structures ◽

Spectroscopic Data ◽

Variable Parameter ◽

Coulomb Repulsion ◽

Resonance Integral ◽

Electronic Transitions ◽

The Core ◽

Lcao Mo

The semiempirical SCF–LCAO–MO method of Pariser–Parr–Pople is utilized in the study of the π-electronic structures of thiophene, furan, and pyrrole. The core Hamiltonian expansion contains a Uz++ term, the potential due to the ionized hetero-atom contributing two electrons to the π-system. The γzz, one-center coulomb repulsion integral for the hetero-atom is evaluated from the experimental spectroscopic data only. With the resonance integral βczc as the only variable parameter, the calculated π*–π electronic transitions are in a satisfactory agreement with the experimental data.

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Mono-energetic ions from collisionless expansion of spherical multi-species clusters

Laser and Particle Beams ◽

10.1017/s0263034609000421 ◽

2009 ◽

Vol 27 (2) ◽

pp. 321-326 ◽

Cited By ~ 10

Author(s):

K.I. Popov ◽

V.Yu. Bychenkov ◽

W. Rozmus ◽

V.F. Kovalev ◽

R.D. Sydora

Keyword(s):

Electron Temperature ◽

Time Evolution ◽

Hot Electrons ◽

Ion Concentration ◽

Energy Spectra ◽

Plasma Expansion ◽

Energetic Ions ◽

Spherical Cluster ◽

Light Ions ◽

Unified Description

AbstractKinetic collisionless expansion of a spherical cluster composed of light and heavy cold ions and hot electrons is studied for arbitrary electron temperature. A wide set of regimes of plasma expansion, from nearly quasi-neutral to Coulomb explosion, is described from a unified description. The time evolution of the velocity, density, and energy spectra for accelerated ions is studied. The study demonstrates that an optimum light ion concentration from few percent to few tens percent, depending on the electron temperature, leads to a quasi-monoenergetic spectra with numbers as high as 70–80% of the total number of light ions.

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Stopping power and multiple scattering of Havar and Kapton for low energy protons

Nuclear Instruments and Methods ◽

10.1016/0029-554x(79)90679-7 ◽

1979 ◽

Vol 159 (2-3) ◽

pp. 513-516 ◽

Cited By ~ 18

Author(s):

F. Foroughi ◽

B. Vuilleumier ◽

E. Bovet

Keyword(s):

Multiple Scattering ◽

Low Energy ◽

Stopping Power

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A Statistical Adaptable Distribution Function Model for Low Probabilities of Failure

10th Biennial Conference on Reliability, Stress Analysis, and Failure Prevention ◽

10.1115/detc1993-0063 ◽

1993 ◽

Author(s):

Suryaji R. Bhonsle ◽

Paul Thompson

Keyword(s):

Experimental Data ◽

Distribution Function ◽

Experimental Results ◽

Function Model ◽

Log Normal ◽

Function Models

Abstract Weibull, log normal, and some other Distribution function models (D.F.M.) have a tendency to deviate from experimental results. This deviation, either exceedingly conservative or nonconservative, is amplified at low probabilities of failure. To remedy such problems a new D.F.M. is derived. It is then used to predict low probabilities of failure. The predictions are consistent with experimental data and are not too conservative or too nonconservative.

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The probe particle scattering cross-section off the many-fermion systems in the impulse approximation

International Journal of Modern Physics E ◽

10.1142/s0218301321501019 ◽

2021 ◽

Author(s):

Yahya Younesizadeh ◽

Fayzollah Younesizadeh

Keyword(s):

Experimental Data ◽

Distribution Function ◽

Spectral Function ◽

Cross Section ◽

Response Function ◽

Momentum Distribution ◽

Impulse Approximation ◽

System Response ◽

Probe Particle ◽

Momentum Distribution Function

In this work, we study the differential scattering cross-section (DSCS) in the first-order Born approximation. It is not difficult to show that the DSCS can be simplified in terms of the system response function. Also, the system response function has this property to be written in terms of the spectral function and the momentum distribution function in the impulse approximation (IA) scheme. Therefore, the DSCS in the IA scheme can be formulated in terms of the spectral function and the momentum distribution function. On the other hand, the DSCS for an electron off the [Formula: see text] and [Formula: see text] nuclei is calculated in the harmonic oscillator shell model. The obtained results are compared with the experimental data, too. The most important result derived from this study is that the calculated DSCS in terms of the spectral function has a high agreement with the experimental data at the low-energy transfer, while the obtained DSCS in terms of the momentum distribution function does not. Therefore, we conclude that the response of a many-fermion system to a probe particle in IA must be written in terms of the spectral function for getting accurate theoretical results in the field of collision. This is another important result of our study.

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Gas transport in a model derived from Hansen-Ampaya anatomical data of the human lung

Journal of Applied Physiology ◽

10.1152/jappl.1976.41.1.115 ◽

1976 ◽

Vol 41 (1) ◽

pp. 115-119 ◽

Cited By ~ 30

Author(s):

M. Paiva ◽

L. M. Lacquet ◽

L. P. van der Linden

Keyword(s):

Experimental Data ◽

Transport Equation ◽

Satisfactory Agreement ◽

Dead Space ◽

Empirical Formula ◽

Molecular Diffusion ◽

Human Lung ◽

Gas Transport ◽

Gas Mixing ◽

Anatomical Data

The anatomical data of the human lung published by Hansen and Ampaya are used in a model of gas transport in the lung. The Bohr dead space is calculated from solutions of a transport equation where diffusivity is given by an empirical formula obtained by Sherer et al. A satisfactory agreement is found with experimental data obtained from simultaneous washouts of H2 and SF6 for respiratory frequencies ranging between 15 and 60 min-1 and tidal volumes between 200 and 1,800 ml. The results support the idea that molecular diffusion is the main but not the only physical phenomenom which intervenes in gas mixing during breathing.

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