scholarly journals ADVANCING THE FUNDAMENTAL UNDERSTANDING AND SCALE-UP OF TRISO FUEL COATERS VIA ADVANCED MEASUREMENT AND COMPUTATIONAL TECHNIQUES

2012 ◽  
Author(s):  
Pratim Biswas ◽  
Muthanna Al-Dahhan
Keyword(s):  
Scale Up ◽  
Computational Techniques ◽  
Triso Fuel ◽  
Fundamental Understanding

scholarly journals Mining Process and Product Information From Pressure Fluctuations Within a Fuel Particle Coater

2009 ◽  
Vol 132 (1) ◽  
Author(s):  
Douglas W. Marshall ◽  
Charles M. Barnes
Keyword(s):  
Nuclear Power ◽  
Product Information ◽  
Pressure Fluctuations ◽  
Scale Up ◽  
Differential Pressure ◽  
Fuel Particle ◽  
Triso Fuel ◽  
Product And Process ◽  
Operation Pressure ◽  
Particle Bed

The next generation nuclear power/advanced gas reactor (NGNP/AGR) fuel development and qualification program included the design, installation, and testing of a 6-in. diameter nuclear fuel particle coater to demonstrate quality tri-structural isotropic (TRISO) fuel production on a small industrial scale. Scale-up from the laboratory-scale coater faced challenges associated with an increase in the kernel charge mass, kernel diameter, and a redesign of the gas distributor to achieve adequate fluidization throughout the deposition of the four TRISO coating layers. TRISO coatings are applied at very high temperatures in atmospheres of dense particulate clouds, corrosive gases, and hydrogen concentrations over 45% by volume. The severe environment, stringent product and process requirements, and the fragility of partially-formed coatings limit the insertion of probes or instruments into the coater vessel during operation. Pressure instrumentation were installed on the gas inlet line and exhaust line of the 6-in. coater to monitor the bed differential pressure and internal pressure fluctuations emanating from the fuel bed as a result of bed and gas “bubble” movements. These instruments are external to the particle bed and provide a glimpse into the dynamics of fuel particle bed during the coating process and data that could be used to help ascertain the adequacy of fluidization and, potentially, the dominant fluidization regimes. Pressure fluctuation and differential pressure data are not presently useful as process control instruments, but data suggest a link between the pressure signal structure and some measurable product attributes that could be exploited to get an early estimate of the attribute values.

Combinatorial methods in advanced battery materials design

2021 ◽  
Author(s):  
Eric McCalla ◽  
Matthew Parmaklis ◽  
Sarish Rehman ◽  
Ethan Anderson ◽  
Shipeng Jia ◽  
...  
Keyword(s):  
High Throughput ◽  
Electrochemical Impedance ◽  
Scale Up ◽  
Computational Techniques ◽  
Synthesis Methods ◽  
Cyclic Voltammograms ◽  
Data Set ◽  
Battery Materials ◽  
Current Limit ◽  
Li Ion

In the search for better performing battery materials, researchers have increasingly ventured into complex composition spaces, including numerous pseudo-quaternaries, with numerous further substitutions being either explored experimentally or proposed based on computation. Given the vast composition spaces that need exploring, experimental combinatorial science can play an important role in accelerating the development of advanced battery materials and is arguably the best means to obtain a sufficiently large data set to truly bring a high degree of precision to advanced computational techniques such as machine-learning. Herein, we present a robust high-throughput synthesis platform that is currently being used in the McCalla lab at McGill University to study Li-ion cathodes, anodes and solid electrolytes, as well as Na-ion cathodes. The synthesis methods used are presented in detail, as are the high-throughput characterization techniques we utilize regularly (X-ray diffraction, electrochemical testing and electrochemical impedance spectroscopy). We quantitatively determine the high precision and reproducibility achieved by this combinatorial system and also demonstrate its versatility by presenting for the first time combinatorial data for two high-power anodes for Li-ion batteries (TiNb2O7 and W3-Nb14O44) as well as solid state electrolyte Li7La3Zr2O12. Our methods reproduce accurately the results from the literature for bulk samples, indicating that the high-throughput methodology utilizing small mg-scale samples scale up extremely well to the larger sample sizes typically used in both the literature and industry. The throughput of this combinatorial infrastructure has a current limit of 896 XRD patterns and 896 EIS patterns a week, and 448 cyclic voltammograms running simultaneously.

scholarly journals A parallelized strategy for epistasis analysis based on Empirical Bayesian Elastic Net models

2020 ◽  
Vol 36 (12) ◽  
pp. 3803-3810
Author(s):  
Jia Wen ◽  
Colby T Ford ◽  
Daniel Janies ◽  
Xinghua Shi
Keyword(s):  
Genetic Variants ◽  
Computing Time ◽  
Scale Up ◽  
Search Space ◽  
Elastic Net ◽  
Computational Techniques ◽  
Saturated Model ◽  
Empirical Bayesian ◽  
Epistasis Analysis ◽  
Yeast Dataset

Abstract Motivation Epistasis reflects the distortion on a particular trait or phenotype resulting from the combinatorial effect of two or more genes or genetic variants. Epistasis is an important genetic foundation underlying quantitative traits in many organisms as well as in complex human diseases. However, there are two major barriers in identifying epistasis using large genomic datasets. One is that epistasis analysis will induce over-fitting of an over-saturated model with the high-dimensionality of a genomic dataset. Therefore, the problem of identifying epistasis demands efficient statistical methods. The second barrier comes from the intensive computing time for epistasis analysis, even when the appropriate model and data are specified. Results In this study, we combine statistical techniques and computational techniques to scale up epistasis analysis using Empirical Bayesian Elastic Net (EBEN) models. Specifically, we first apply a matrix manipulation strategy for pre-computing the correlation matrix and pre-filter to narrow down the search space for epistasis analysis. We then develop a parallelized approach to further accelerate the modeling process. Our experiments on synthetic and empirical genomic data demonstrate that our parallelized methods offer tens of fold speed up in comparison with the classical EBEN method which runs in a sequential manner. We applied our parallelized approach to a yeast dataset, and we were able to identify both main and epistatic effects of genetic variants associated with traits such as fitness. Availability and implementation The software is available at github.com/shilab/parEBEN.

scholarly journals Mining Process and Product Information From Pressure Fluctuations Within a Fuel Particle Coater

2008 ◽  
Author(s):  
Douglas W. Marshall ◽  
Charles M. Barnes
Keyword(s):  
Nuclear Power ◽  
Product Information ◽  
Pressure Fluctuations ◽  
Scale Up ◽  
Differential Pressure ◽  
Fuel Particle ◽  
Triso Fuel ◽  
Product And Process ◽  
Operation Pressure ◽  
Particle Bed

The Next Generation Nuclear Power/Advanced Gas Reactor (NGNP/AGR) Fuel Development and Qualification Program included the design, installation, and testing of a 6-inch diameter nuclear fuel particle coater to demonstrate quality TRISO fuel production on a small industrial scale. Scale-up from the laboratory-scale coater faced challenges associated with an increase in the kernel charge mass, kernel diameter, and a redesign of the gas distributor to achieve adequate fluidization throughout the deposition of the four TRISO coating layers. TRISO coatings are applied at very high temperatures in atmospheres of dense particulate clouds, corrosive gases, and hydrogen concentrations over 45% by volume. The severe environment, stringent product and process requirements, and the fragility of partially-formed coatings limit the insertion of probes or instruments into the coater vessel during operation. Pressure instrumentation were installed on the gas inlet line and exhaust line of the 6-inch coater to monitor the bed differential pressure and internal pressure fluctuations emanating from the fuel bed as a result of bed and gas “bubble” movement. These instruments are external to the particle bed and provide a glimpse into the dynamics of fuel particle bed during the coating process and data that could be used to help ascertain the adequacy of fluidization and, potentially, the dominant fluidization regimes. Pressure fluctuation and differential pressure data are not presently useful as process control instruments, but data suggest a link between the pressure signal structure and some measurable product attributes that could be exploited to get an early estimate of the attribute values.

Mass Transfer Considerations in the Design of Vapor-Phase photocatalytic Reactors

1998 ◽  
Vol 3 (2) ◽  
Author(s):  
Ali Τ- Raissi ◽  
Eric D. Martin ◽  
Sivakumar Jaganathan
Keyword(s):  
Fluid Dynamics ◽  
Experimental Data ◽  
Mass Transfer ◽  
Computational Fluid Dynamics ◽  
Flow Field ◽  
Vapor Phase ◽  
Flow Reactor ◽  
Scale Up ◽  
Computational Techniques ◽  
Photocatalytic Reactors

AbstractAs the bench-scale photoreactors are upscaled to progressively larger units, heat and mass transfer considerations become increasingly important. Powerful analytical and computational techniques are available to augment experimental data and aid process optimization and scale up. In this paper, the analytical and computational techniques available for the design of vapor-phase photocatalytic reactors are discussed. First, the Graetz- Nusselt-Leveque problem in annuli is analyzed and its application to the design of the photocatalytic reactors described. Then, the analytical predications are compared to experimental flow reactor data. Finally, results from a Computational Fluid Dynamics program simulating a flow field within an annular baffled photoreactor are given and discussed. These techniques are particularly useful as they simplify the design and scale-up of vapor-phase photocatalytic reactors.

scholarly journals Computational Tools to Rationalize and Predict the Self-Assembly Behavior of Supramolecular Gels

Gels ◽  
2021 ◽  
Vol 7 (3) ◽  
pp. 87
Author(s):  
Ruben Van Lommel ◽  
Wim M. De Borggraeve ◽  
Frank De Proft ◽  
Mercedes Alonso
Keyword(s):  
Self Assembly ◽  
Soft Materials ◽  
The Self ◽  
Computational Techniques ◽  
Computational Tools ◽  
The Past ◽  
Fundamental Understanding ◽  
Supramolecular Gels ◽  
Future Challenges ◽  
Assembly Behavior

Supramolecular gels form a class of soft materials that has been heavily explored by the chemical community in the past 20 years. While a multitude of experimental techniques has demonstrated its usefulness when characterizing these materials, the potential value of computational techniques has received much less attention. This review aims to provide a complete overview of studies that employ computational tools to obtain a better fundamental understanding of the self-assembly behavior of supramolecular gels or to accelerate their development by means of prediction. As such, we hope to stimulate researchers to consider using computational tools when investigating these intriguing materials. In the concluding remarks, we address future challenges faced by the field and formulate our vision on how computational methods could help overcoming them.

NiAl precipitation in Fe-12w/o Cr-5w/o Ni-4w/o Al

1983 ◽  
Vol 41 ◽  
pp. 202-203
Author(s):  
L.E. Murr ◽  
J.S. Dunning ◽  
S. Shankar
Keyword(s):  
Solid Solution ◽  
Stainless Steel ◽  
Stainless Steels ◽  
Alloy Composition ◽  
Chromium Content ◽  
Scale Up ◽  
Optical Metallography ◽  
Property Evaluation ◽  
310 Stainless Steel ◽  
Microstructural Studies

Aluminum additions to conventional 18Cr-8Ni austenitic stainless steel compositions impart excellent resistance to high sulfur environments. However, problems are typically encountered with aluminum additions above about 1% due to embrittlement caused by aluminum in solid solution and the precipitation of NiAl. Consequently, little use has been made of aluminum alloy additions to stainless steels for use in sulfur or H2S environments in the chemical industry, energy conversion or generation, and mineral processing, for example.A research program at the Albany Research Center has concentrated on the development of a wrought alloy composition with as low a chromium content as possible, with the idea of developing a low-chromium substitute for 310 stainless steel (25Cr-20Ni) which is often used in high-sulfur environments. On the basis of workability and microstructural studies involving optical metallography on 100g button ingots soaked at 700°C and air-cooled, a low-alloy composition Fe-12Cr-5Ni-4Al (in wt %) was selected for scale up and property evaluation.

Strain analysis in composite ceramics

1986 ◽  
Vol 44 ◽  
pp. 494-497
Author(s):  
W. M. Kriven
Keyword(s):  
Strain Field ◽  
Strain Analysis ◽  
Processing Temperature ◽  
Transformation Toughening ◽  
Zirconia Ceramics ◽  
Volume Increase ◽  
Analysis Technique ◽  
Fundamental Understanding ◽  
Contrast Analysis ◽  
Elastic Strain Field

Significant progress towards a fundamental understanding of transformation toughening in composite zirconia ceramics was made possible by the application of a TEM contrast analysis technique for imaging elastic strains. Spherical zirconia particles dispersed in a large-grained alumina matrix were examined by 1 MeV HVEM to simulate bulk conditions. A thermal contraction mismatch arose on cooling from the processing temperature of 1500°C to RT. Tetragonal ZrO2 contracted amisotropically with α(ct) = 16 X 10-6/°C and α(at) = 11 X 10-6/°C and faster than Al2O3 which contracted relatively isotropically at α = 8 X 10-6/°C. A volume increase of +4.9% accompanied the transformation to monoclinic symmetry at room temperature. The elastic strain field surrounding a particle before transformation was 3-dimensionally correlated with the internal crystallographic orientation of the particle and with the strain field after transformation. The aim of this paper is to theoretically and experimentally describe this technique using the ZrO2 as an example and thereby to illustrate the experimental requirements Tor such an analysis in other systems.

Progress and perspectives on halide lithium conductors for all-solid-state lithium batteries

2020 ◽  
Vol 13 (5) ◽  
pp. 1429-1461 ◽  
Author(s):  
Xiaona Li ◽  
Jianwen Liang ◽  
Xiaofei Yang ◽  
Keegan R. Adair ◽  
Changhong Wang ◽  
...  
Keyword(s):  
Energy Storage ◽  
Solid State ◽  
Lithium Batteries ◽  
Electrochemical Stability ◽  
Superionic Conductors ◽  
Fundamental Understanding ◽  
Potential Applications ◽  
Synthesis Routes

This review focuses on fundamental understanding, various synthesis routes, chemical/electrochemical stability of halide-based lithium superionic conductors, and their potential applications in energy storage as well as related challenges.

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