Dynamic Average Diffusion With Randomized Coordinate Updates

The diffusion behavior of fluid water in nanochannels with hydroxylation of silica gel and silanization of different modified chain lengths was simulated by the equilibrium molecular dynamics method. The diffusion coefficient of fluid water was calculated by the Einstein method and the Green–Kubo method, so as to analyze the change rule between the modification degree of nanochannels and the diffusion coefficient of fluid water. The results showed that the diffusion coefficient of fluid water increased with the length of the modified chain. The average diffusion coefficient of fluid water in the hydroxylated nanochannels was 8.01% of the bulk water diffusion coefficient, and the diffusion coefficients of fluid water in the –(CH2)3CH3, –(CH2)7CH3, and –(CH2)11CH3 nanochannels were 44.10%, 49.72%, and 53.80% of the diffusion coefficients of bulk water, respectively. In the above four wall characteristic models, the diffusion coefficients in the z direction were smaller than those in the other directions. However, with an increase in the silylation degree, the increased self-diffusion coefficient due to the surface effect could basically offset the decreased self-diffusion coefficient owing to the scale effect. In the four nanochannels, when the local diffusion coefficient of fluid water was in the range of 8 Å close to the wall, Dz was greater than Dxy, and beyond the range of 8 Å of the wall, the Dz was smaller than Dxy.

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Local and Average Diffusion of Nanosolutes in Agarose Gel: The Effect of the Gel/Solution Interface Structure

Langmuir ◽

10.1021/la0611155 ◽

2007 ◽

Vol 23 (4) ◽

pp. 2083-2090 ◽

Cited By ~ 25

Author(s):

Jérôme Labille ◽

Nicolas Fatin-Rouge ◽

Jacques Buffle

Keyword(s):

Interface Structure ◽

Agarose Gel ◽

Solution Interface ◽

Average Diffusion

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Molten Slag Structure and Diffusion Coefficients of Cr3+ and Si4+ during Micro-Carbon Cr-Fe Alloy Production

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.79.77 ◽

2011 ◽

Vol 79 ◽

pp. 77-82

Author(s):

Yi Min ◽

Jian Huang ◽

Cheng Jun Liu ◽

Mao Fa Jiang

Keyword(s):

Diffusion Coefficient ◽

Diffusion Coefficients ◽

Molten Slag ◽

Optimization Method ◽

Structure Theory ◽

Average Diffusion Coefficient ◽

Slag Structure ◽

Initial Stage ◽

Silicate Structure ◽

Average Diffusion

Based on the silicate structure theory, the molten slag structure and the existential state of and during micro-carbon Cr-Fe alloy production process were analysised, and then their diffusion coefficients were calculated. The results showed that, during the initial stage, the average diffusion coeffecient of and is close to the , the reaction process is controlled by the diffusion of () and corporately, during the later stage, the diffusion coefficient of is less than average diffusion coefficient of and , the controlling step is the diffusion of . According to the evolution of diffusion coefficient, molten slag composition optimization method was advised to increase the diffusion ability of and for enhancing the reaction efficiency and the recovery rate of chromium.

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Excellent Average Diffusion Lengths of 600 μm of N-Type Multicrystalline Silicon Wafers After the Full Solar Cell Process Including Boron Diffusion

Energy Procedia ◽

10.1016/j.egypro.2013.05.038 ◽

2013 ◽

Vol 33 ◽

pp. 41-49 ◽

Cited By ~ 6

Author(s):

Bernhard Michl ◽

Jan Benick ◽

Armin Richter ◽

Martin Bivour ◽

Jeannie Yong ◽

...

Keyword(s):

Solar Cell ◽

Silicon Wafers ◽

Multicrystalline Silicon ◽

Cell Process ◽

Boron Diffusion ◽

Average Diffusion

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Diffusion of Water in the Wheat Grain: Nuclear Magnetic Resonance and Radioisotopic Methods Provide Complementary Information

Functional Plant Biology ◽

10.1071/pp9900107 ◽

1990 ◽

Vol 17 (2) ◽

pp. 107 ◽

Cited By ~ 6

Author(s):

CF Jenner ◽

GP Jones

Keyword(s):

Diffusion Coefficient ◽

Tritiated Water ◽

Free Water ◽

Wheat Grain ◽

Freezing And Thawing ◽

Complementary Information ◽

Average Diffusion Coefficient ◽

Average Diffusion ◽

Polymeric Component ◽

Developing Grains

Diffusion of water within developing grains of wheat has been evaluated by two independent methods: by kinetic analysis of the movement of tritiated water (THO) through the grain, and by n.m.r. procedures. Both methods provided different but complementary information. Movement of THO basipetally through grains attached to the ear was faster than diffusion could explain, and a reversal of the gradient of THO at the base of the grain also could not be accounted for by diffusion. These observations are adduced as evidence for recirculation of water within the grain. The average diffusion coefficient measured by both methods indicated that the diffusive motion of water was substantially hindered. Freezing and thawing resulted in an increase in diffusion but did not increase diffusion to values expected of free water. Starch, the major polymeric component of the grain, was not responsible for the residual reduction in diffusion coefficient in frozen and thawed tissue.

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Alternative Microstructural Measures to Complement Diffusion Tensor Imaging in Migraine Studies with Standard MRI Acquisition

Brain Sciences ◽

10.3390/brainsci10100711 ◽

2020 ◽

Vol 10 (10) ◽

pp. 711

Author(s):

Álvaro Planchuelo-Gómez ◽

David García-Azorín ◽

Ángel L. Guerrero ◽

Rodrigo de Luis-García ◽

Margarita Rodríguez ◽

...

Keyword(s):

Diffusion Tensor Imaging ◽

White Matter ◽

Chronic Migraine ◽

Diffusion Tensor ◽

Mean Diffusivity ◽

Episodic Migraine ◽

Healthy Controls ◽

Axial Diffusivity ◽

Average Diffusion ◽

Cerebellar Peduncle

The white matter state in migraine has been investigated using diffusion tensor imaging (DTI) measures, but results using this technique are conflicting. To overcome DTI measures, we employed ensemble average diffusion propagator measures obtained with apparent measures using reduced acquisitions (AMURA). The AMURA measures were return-to-axis (RTAP), return-to-origin (RTOP) and return-to-plane probabilities (RTPP). Tract-based spatial statistics was used to compare fractional anisotropy, mean diffusivity, axial diffusivity and radial diffusivity from DTI, and RTAP, RTOP and RTPP, between healthy controls, episodic migraine and chronic migraine patients. Fifty healthy controls, 54 patients with episodic migraine and 56 with chronic migraine were assessed. Significant differences were found between both types of migraine, with lower axial diffusivity values in 38 white matter regions and higher RTOP values in the middle cerebellar peduncle in patients with a chronic migraine (p < 0.05 family-wise error corrected). Significantly lower RTPP values were found in episodic migraine patients compared to healthy controls in 24 white matter regions (p < 0.05 family-wise error corrected), finding no significant differences using DTI measures. The white matter microstructure is altered in a migraine, and in chronic compared to episodic migraine. AMURA can provide additional results with respect to DTI to uncover white matter alterations in migraine.

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Anisotropic diffusion of fluorescently labeled ATP in rat cardiomyocytes determined by raster image correlation spectroscopy

AJP Cell Physiology ◽

10.1152/ajpcell.00313.2008 ◽

2008 ◽

Vol 295 (5) ◽

pp. C1302-C1315 ◽

Cited By ~ 47

Author(s):

Marko Vendelin ◽

Rikke Birkedal

Keyword(s):

Diffusion Coefficient ◽

Diffusion Coefficients ◽

Anisotropic Diffusion ◽

Correlation Spectroscopy ◽

Image Correlation ◽

Rat Cardiomyocytes ◽

Intracellular Diffusion ◽

Average Diffusion ◽

Image Correlation Spectroscopy ◽

Kinetics Of

A series of experimental data points to the existence of profound diffusion restrictions of ADP/ATP in rat cardiomyocytes. This assumption is required to explain the measurements of kinetics of respiration, sarcoplasmic reticulum loading with calcium, and kinetics of ATP-sensitive potassium channels. To be able to analyze and estimate the role of intracellular diffusion restrictions on bioenergetics, the intracellular diffusion coefficients of metabolites have to be determined. The aim of this work was to develop a practical method for determining diffusion coefficients in anisotropic medium and to estimate the overall diffusion coefficients of fluorescently labeled ATP in rat cardiomyocytes. For that, we have extended raster image correlation spectroscopy (RICS) protocols to be able to discriminate the anisotropy in the diffusion coefficient tensor. Using this extended protocol, we estimated diffusion coefficients of ATP labeled with the fluorescent conjugate Alexa Fluor 647 (Alexa-ATP). In the analysis, we assumed that the diffusion tensor can be described by two values: diffusion coefficient along the myofibril and that across it. The average diffusion coefficients found for Alexa-ATP were as follows: 83 ± 14 μm2/s in the longitudinal and 52 ± 16 μm2/s in the transverse directions ( n = 8, mean ± SD). Those values are ∼2 (longitudinal) and ∼3.5 (transverse) times smaller than the diffusion coefficient value estimated for the surrounding solution. Such uneven reduction of average diffusion coefficient leads to anisotropic diffusion in rat cardiomyocytes. Although the source for such anisotropy is uncertain, we speculate that it may be induced by the ordered pattern of intracellular structures in rat cardiomyocytes.

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Select cytoplasmic and membrane proteins increase the percentage of immobile integrins but do not affect the average diffusion coefficient of mobile integrins

Analytical and Bioanalytical Chemistry ◽

10.1007/s00216-013-7279-1 ◽

2013 ◽

Vol 405 (26) ◽

pp. 8561-8568 ◽

Cited By ~ 3

Author(s):

Dipak Mainali ◽

Emily A. Smith

Keyword(s):

Diffusion Coefficient ◽

Membrane Proteins ◽

Average Diffusion Coefficient ◽

Average Diffusion

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Modeling the Diffusion Mechanism and the Reaction Kinetics for the Photocatalytic Degradation of Acid Red 151 Aqueous Solutions by ZnO: Comparison of Linear and Non-Linear Methods

Journal of Advanced Oxidation Technologies ◽

10.1515/jaots-2007-0234 ◽

2007 ◽

Vol 10 (2) ◽

Author(s):

K. Vasanth Kumar ◽

K. Porkodi

Keyword(s):

Aqueous Solution ◽

Diffusion Coefficient ◽

Aqueous Solutions ◽

Photocatalytic Degradation ◽

Reaction Kinetics ◽

Diffusion Mechanism ◽

Batch Processes ◽

Average Diffusion Coefficient ◽

Diffusion Controlled ◽

Average Diffusion

AbstractBatch processes were carried out for the photocatalytic degradation of Acid Red 151 from its aqueous solution using ZnO catalyst at different initial dye concentrations. The process was found to be diffusion controlled for the first 15-20 minutes (before irradiation) with an average diffusion coefficient of 6.759 × 10

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Monitoring human parvovirus B19 virus-like particles and antibody complexes in solution by fluorescence correlation spectroscopy

Biological Chemistry ◽

10.1515/bc.2004.011 ◽

2004 ◽

Vol 385 (1) ◽

pp. 87-93 ◽

Cited By ~ 3

Author(s):

J. Toivola ◽

P. O. Michel ◽

L. Gilbert ◽

T. Lahtinen ◽

V. Marjomäki ◽

...

Keyword(s):

Diffusion Coefficient ◽

Serum Sample ◽

Acute Phase ◽

Fluorescence Correlation Spectroscopy ◽

Parvovirus B19 ◽

Correlation Spectroscopy ◽

Human Parvovirus B19 ◽

Fluorescence Correlation ◽

Average Diffusion Coefficient ◽

Average Diffusion

AbstractFluorescence correlation spectroscopy (FCS) was used in monitoring human parvovirus B19 virus-like particle (VLP) antibody complexes from acute phase and pastimmunity serum samples. The Oregon Green 488-labeled VLPs gave an average diffusion coefficient of 1.7x10exp-7 cm(2)s(-1) with an apparent hydrodynamic radius of 14 nm. After incubation of the fluorescent VLPs with an acute phase serum sample, the mobility information obtained from the fluorescence intensity fluctuation by autocorrelation analysis showed an average diffusion coefficient of 1.5x10exp-8 cm(2)s(-1), corresponding to an average radius of 157 nm. In contrast, incubation of the fluorescent VLPs with a pastimmunity serum sample gave an average diffusion coefficient of 3.5x10exp-8 cm(2)s(-1) and a radius of 69 nm. A control serum devoid of B19 antibodies caused a change in the diffusion coefficient from 1.7x10exp-7 to 1.6x10exp-7 cm(2)s(-1), which is much smaller than that observed with acute phase or pastimmunity sera. Thus, VLP-antibody complexes with different diffusion coefficients could be identified for the acute phase and pastimmunity sera. FCS measurement of VLPimmune complexes could be useful in distinguishing between antibodies present in acute phase or past-immunity sera as well as in titration of the VLPs.

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