scholarly journals Intergranular diffusion rates from the analysis of garnet surfaces: Implications for metamorphic equilibration

2017 ◽  
Vol 35 (6) ◽  
pp. 585-600 ◽  
Author(s):  
Tim J. Dempster ◽  
Shona Symon ◽  
Peter Chung
Keyword(s):  
Diffusion Rates ◽  
Intergranular Diffusion

scholarly journals Factors to consider when interrogating 3D culture models with plate readers or automated microscopes

2021 ◽  
Author(s):  
Terry Riss ◽  
O. Joseph Trask
Keyword(s):  
Cell Culture ◽  
Three Dimensional ◽  
3D Culture ◽  
Fluorescent Imaging ◽  
Culture Models ◽  
Assay Methods ◽  
Diffusion Rates ◽  
Cell Culture Models ◽  
Dimensional Cell ◽  
Cells Cultured

AbstractAlong with the increased use of more physiologically relevant three-dimensional cell culture models comes the responsibility of researchers to validate new assay methods that measure events in structures that are physically larger and more complex compared to monolayers of cells. It should not be assumed that assays designed using monolayers of cells will work for cells cultured as larger three-dimensional masses. The size and barriers for penetration of molecules through the layers of cells result in a different microenvironment for the cells in the outer layer compared to the center of three-dimensional structures. Diffusion rates for nutrients and oxygen may limit metabolic activity which is often measured as a marker for cell viability. For assays that lyse cells, the penetration of reagents to achieve uniform cell lysis must be considered. For live cell fluorescent imaging assays, the diffusion of fluorescent probes and penetration of photons of light for probe excitation and fluorescent emission must be considered. This review will provide an overview of factors to consider when implementing assays to interrogate three dimensional cell culture models.

scholarly journals Macro Patterns and Trends of U.S. Consumer Technological Innovation Diffusion Rates

Systems ◽  
2021 ◽  
Vol 9 (1) ◽  
pp. 16
Author(s):  
Albert Joseph Parvin ◽  
Mario G. Beruvides
Keyword(s):  
Innovation Diffusion ◽  
Technological Innovation ◽  
Research Effort ◽  
Decision Makers ◽  
Macro Level ◽  
Technological Innovations ◽  
Exploratory Data ◽  
Diffusion Rates ◽  
Technological Innovation Diffusion ◽  
Aid Decision

Macro-level trends and patterns are commonly used in business, science, finance, and engineering to provide insights and estimates to assist decision-makers. In this research effort, macro-level trends and patterns were explored on the diffusion rates of technological innovations, a component of a sorely under-studied question in technology assessment: When should a technological innovation be abandoned? A quantitative exploratory data analysis (EDA)-based approach was employed to examine diffusion market data of 42 U.S. consumer technological innovations from the early 1900s to the 2010s to extract general macro-level knowledge on technological innovation diffusion rates. A goal of this effort is to grow diffusion rate knowledge to enable the development of general macro-based forecasting tools. Such tools would aid decision-makers in making informed and proactive decisions on when to abandon a technological innovation. This research offers several significant contributions to the macro-level understanding of the boundaries and likelihood of achieving a range of technological innovation diffusion rates. These contributions include the determination that the frequency of diffusion rates are positively skewed when ordered from slowest to fastest, and the identification and ranking of probability density functions that best represent the rates of technological innovation diffusion.

Determination of diffusion rates in acrylamide-based photopolymer material

2006 ◽  
Author(s):  
C. E. Close ◽  
M. R. Gleeson ◽  
J. V. Kelly ◽  
F. T. O'Neill ◽  
D. Mooney ◽  
...  
Keyword(s):  
Diffusion Rates

scholarly journals The roles of vertical advection and eddy diffusion in the equatorial mesospheric semi-annual oscillation (MSAO)

2013 ◽  
Vol 13 (15) ◽  
pp. 7813-7824 ◽  
Author(s):  
R. L. Gattinger ◽  
E. Kyrölä ◽  
C. D. Boone ◽  
W. F. J. Evans ◽  
K. A. Walker ◽  
...  
Keyword(s):  
Driving Forces ◽  
Eddy Diffusion ◽  
Equatorial Region ◽  
Local Times ◽  
Model Simulations ◽  
Vertical Advection ◽  
Diffusion Rates ◽  
D Model ◽  
Vertical Eddy

Abstract. Observations of the mesospheric semi-annual oscillation (MSAO) in the equatorial region have been reported dating back several decades. Seasonal variations in both species densities and airglow emissions are well documented. The extensive observations available offer an excellent case study for comparison with model simulations. A broad range of MSAO measurements is summarised with emphasis on the 80–100 km region. The objective here is not to address directly the complicated driving forces of the MSAO, but rather to employ a combination of observations and model simulations to estimate the limits of some of the underlying dynamical processes. Photochemical model simulations are included for near-equinox and near-solstice conditions, the two times with notable differences in the observed MSAO parameters. Diurnal tides are incorporated in the model to facilitate comparisons of observations made at different local times. The roles of water vapour as the "driver" species and ozone as the "response" species are examined to test for consistency between the model results and observations. The simulations suggest the interactions between vertical eddy diffusion and background vertical advection play a significant role in the MSAO phenomenon. Further, the simulations imply there are rigid limits on vertical advection rates and eddy diffusion rates. For August at the Equator, 90 km altitude, the derived eddy diffusion rate is approximately 1 × 106 cm2 s−1 and the vertical advection is upwards at 0.8 cm s−1. For April the corresponding values are 4 × 105 cm2 s−1 and 0.1 cm s−1. These results from the current 1-D model simulations will need to be verified by a full 3-D simulation. Exactly how vertical advection and eddy diffusion are related to gravity wave momentum as discussed by Dunkerton (1982) three decades ago remains to be addressed.

scholarly journals MgFeSiO4 as a potential cathode material for magnesium batteries: ion diffusion rates and voltage trends

2017 ◽  
Vol 5 (25) ◽  
pp. 13161-13167 ◽  
Author(s):  
Jennifer Heath ◽  
Hungru Chen ◽  
M. Saiful Islam
Keyword(s):  
Energy Density ◽  
Cathode Material ◽  
Lithium Ion Batteries ◽  
Lithium Ion ◽  
Ion Diffusion ◽  
Diffusion Rates ◽  
Magnesium Batteries ◽  
Rechargeable Magnesium Batteries

Developing rechargeable magnesium batteries has become an area of growing interest as an alternative to lithium-ion batteries largely due to their potential to offer increased energy density from the divalent charge of the Mg ion.

An Overview of the Interdiffusion Studies in Mo-Si and W-Si Systems

2014 ◽  
Vol 354 ◽  
pp. 79-83
Author(s):  
Soumitra Roy ◽  
Soma Prasad ◽  
Aloke Paul
Keyword(s):  
Crystal Structures ◽  
Atomic Number ◽  
Diffusion Coefficients ◽  
Relative Increase ◽  
The Other ◽  
Reactive Diffusion ◽  
Refractory Elements ◽  
Other Hand ◽  
Two Systems ◽  
Diffusion Rates

The growth of phases by reactive diffusion in Mo-Si and W-Si systems are compared. The crystal structures of MSi2 and M5Si3 phases (M = Mo, W) are similar in these two systems. However, the diffusion rates of the components change systematically with a change in the atomic number. Integrated diffusion coefficients in both phases increase with an increasing atomic number of refractory elements i.e. from Mo to W. On the other hand, the ratio of diffusivities of the components decreases. This indicates a relative increase in the diffusion rates of the metal components with increasing atomic number and a difference in defects concentrations in these two systems.

Variations of the earthquake diffusion rates in the Western Gulf of Corinth (Greece)

2021 ◽  
Author(s):  
Georgios Michas ◽  
Vasilis Kapetanidis ◽  
George Kaviris ◽  
Filippos Vallianatos
Keyword(s):  
Fluid Pressure ◽  
Stress Transfer ◽  
The European Union ◽  
Triggering Mechanism ◽  
Development Education ◽  
Seismic Sequences ◽  
Gulf Of Corinth ◽  
Aftershock Sequences ◽  
Triggering Mechanisms ◽  
Diffusion Rates

<p>Earthquake diffusion is frequently observed in the spatiotemporal evolution of seismic clusters and regional seismicity, a characteristic that is attributed to a triggering mechanism, such as fluid flow, aseismic creep and/or stress transfer effects. In this work, we study the earthquake diffusion properties in the Western Gulf of Corinth (central Greece), an area that presents high extension rates, moderate to large magnitude earthquakes, intense microseismicity and frequent seismic swarms. We focus on the period 2013–2014 that is characterized by intense background microseismic activity along with significant seismic sequences. More specifically, the latter include the 2013 Helike swarm, the 2014 seismic sequence between Nafpaktos and Psathopyrgos, which culminated with an Mw 4.9 event on 21 September 2014, as well as moderate magnitude events that were followed by aftershock sequences. In the herein analysis, we employ a relocated earthquake catalogue of ~9000 events which delineates the activated areas during the study period in high-resolution. We consider the most significant seismic sequences and calculate their respective spatial correlation histograms and the evolution of the mean squared distance of the hypocenters with time, in order to study the earthquake diffusion rates and possible variations that might be related to the triggering mechanisms of seismicity. Our results demonstrate a weak earthquake diffusion process, analogous to subdiffusion within a stochastic framework, for the seismic sequences under consideration, providing further evidence for slow earthquake diffusion in regional and global seismicity. In addition, the earthquake diffusion rates exhibit variations that can be associated with the triggering mechanism. In particular, seismic sequences which are related with pore-fluid pressure diffusion present considerably higher diffusion rates than mainshock/aftershock sequences or the background activity. Such results may provide novel constraints on the triggering mechanisms of clustered seismic activity based on the study of the earthquake diffusion rates. </p><p><strong>Acknowledgements</strong></p><p>We would like to thank the personnel of the Hellenic Unified Seismological Network (http://eida.gein.noa.gr/) and the Corinth Rift Laboratory Network (https://doi.org/10.15778/RESIF.CL) for the installation and operation of the stations used in the current article. The present research is co-financed by Greece and the European Union (European Social Fund- ESF) through the Operational Programme «Human Resources Development, Education and Lifelong Learning 2014-2020» in the context of the project “The role of fluids in the seismicity of the Western Gulf of Corinth (Greece)” (MIS 5048127).</p>

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