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相关论文: Using NMR to Measure Fractal Dimensions

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The magnitude of the relative permittivity of the ferroelectric nematic phase (NF) is under a lively scientific discussion since the phase was recently discovered. Dielectric spectroscopy measurements (DSM) give a huge value of relative…

软凝聚态物质 · 物理学 2024-09-05 Vojko Matko , Ewa Gorecka , Damian Pociecha , Joanna Matraszek , Nataša Vaupotič

Of primary interest in this paper is the numerical approximation of a time dependent fractional, in space, diffusion equation where the domain is assumed to be nonhomogeneous, having different axial diffusion coefficients. This work is…

数值分析 · 数学 2026-05-12 T. Catoe , V. J. Ervin

In analogy to recent results on non-universal roughening in surface growth [Lam and Sander, Phys. Rev. Lett. {\bf 69}, 3338 (1992)], we propose a variant of diffusion-limited aggregation ($DLA$) in which the radii of the particles are…

凝聚态物理 · 物理学 2007-05-23 P. Ossadnik , C. -H. Lam , L. M. Sander

Atomic-scale magnetic field sensors based on nitrogen vacancy (NV) defects in diamonds are an exciting platform for nanoscale nuclear magnetic resonance (NMR) spectroscopy. The detection of NMR signals from a few zeptoliters to single…

A method is described for calculating the approximate fractal dimension from a set of N values y sampled from a waveform between time zero and t. The waveform was subjected to a double linear transformation that maps it into a unit square.

混沌动力学 · 物理学 2010-03-30 Carlos Sevcik

Super-diffusion, characterized by a spreading rate $t^{1/\alpha}$ of the probability density function $p(x,t) = t^{-1/\alpha} p \left( t^{-1/\alpha} x , 1 \right)$, where $t$ is time, may be modeled by space-fractional diffusion equations…

统计力学 · 物理学 2019-02-20 James F. Kelly , Mark M. Meerschaert

Recently, there has been interest in determining the viscoelastic properties of polymeric liquids and other complex fluids by means of Diffusing Wave Spectroscopy (DWS). In this technique, light-scattering spectroscopy is applied to highly…

软凝聚态物质 · 物理学 2024-08-27 George D. J. Phillies

This paper deals with an estimating of the Fractal Dimension of a hydrometeorology variables like an Air temperature or humidity at a different sites in a landscape (and will be further evaluated from the land use point of view). Three…

数据分析、统计与概率 · 物理学 2015-12-04 Jakub Jura , Aleš Antonín Kuběna , Martina Mironovová

Fractals have been at the heart of geophysical and geospatial studies in the recent past. We examine the emergent fractal character of water vapor distributions above the surface of the Earth as a function of both image resolution (number…

斑图形成与孤子 · 物理学 2025-03-24 Anirudha Menon , Banasri Basu

Fractal dimension (D) is an effective parameter to represent the irregularity and fragmental property of a self-affine surface, which is common in physical vapor deposited thin films. D could be evaluated through the scaling performance of…

材料科学 · 物理学 2018-01-30 Feng Feng , Binbin Liu , Xiangsong Zhang , Xiang Qian , Xinghui Li , Timing Qu , Pingfa Feng

If a point particle moves chaotically through a periodic array of scatterers the associated transport coefficients are typically irregular functions under variation of control parameters. For a piecewise linear two-parameter map we analyze…

混沌动力学 · 物理学 2009-11-10 R. Klages , T. Klauss

We present a review of the history and the present state of the fractal approach to the large-scale distribution of galaxies. Angular correlation function was used as a general instrument for the structure analysis. It was realized later…

天体物理学 · 物理学 2007-05-23 Yurij Baryshev , Pekka Teerikorpi

Nuclear magnetic resonance (NMR) experiments are described for two granular-flow systems, the vibrofluidized bed and the gas-fluidized bed. Using pulsed field gradient, magnetic resonance imaging, and hyperpolarized gas NMR, detailed…

软凝聚态物质 · 物理学 2007-05-23 D. Candela , C. Huan , K. Facto , R. Wang , R. W. Mair , R. L. Walsworth

The spatial distribution of unvisited/persistent sites in $d=1$ $A+A\to\emptyset$ model is studied numerically. Over length scales smaller than a cut-off $\xi(t)\sim t^{z}$, the set of unvisited sites is found to be a fractal. The fractal…

统计力学 · 物理学 2007-05-23 G. Manoj , P. Ray

We use Diffusing Wave Spectroscopy (DWS) to perform the first direct space- and time-resolved measurement of the dissipation rate~$\epsilon$ at the boundary of a turbulent flow. We have shown in a previous publication that this technique…

流体动力学 · 物理学 2025-11-06 Enzo Francisco , Julien Lambret , Sébastien Aumaître

$^{1}$H spin-lattice nuclear magnetic resonance (NMR) relaxation experiments have been performed for water dispersions of functionalized silica nanoparticles of diameters of 25 and 45 nm. The experiments have been performed in a broad…

化学物理 · 物理学 2025-01-28 Aleksandra Stankiewicz , Adam Kasparek , Elzbieta Masiewicz , Danuta Kruk

NMR is the technique of election to probe the local properties of materials. Herein we present the results of density functional theory (DFT) \textit{ab initio} calculations of the NMR parameters for fluorapatite (FAp), a calcium…

材料科学 · 物理学 2012-07-27 Barbara Pavan , Davide Ceresoli , Mary M. J. Tecklenburg , Marco Fornari

We report on measurements of self-diffusion coefficients in discrete numerical simulations of steady, homogeneous, collisional shearing flows of nearly identical, frictional, inelastic spheres. We focus on a range of relatively high solid…

软凝聚态物质 · 物理学 2021-04-01 Riccardo Artoni , Michele Larcher , James Jenkins , Patrick Richard

Diffusion is a prominent source of noise affecting nuclear magnetic resonance at the nanometer scale (nano-NMR), preventing high resolution studies of unpolarized liquid samples. Actively managing diffusion noise through, for example,…

量子物理 · 物理学 2025-02-20 Santiago Oviedo Casado , Daniel Cohen , Javier Cerrillo

We study upper estimates of the martingale dimension $d_m$ of diffusion processes associated with strong local Dirichlet forms. By applying a general strategy to self-similar Dirichlet forms on self-similar fractals, we prove that $d_m=1$…

概率论 · 数学 2013-07-30 Masanori Hino