The acoustic properties of granular materials with pore size distribution close to log-normal

2001 ◽  
Vol 110 (5) ◽  
pp. 2371-2378 ◽  
Author(s):  
K. V. Horoshenkov ◽  
M. J. Swift
Keyword(s):  
Pore Size Distribution ◽  
Pore Size ◽  
Size Distribution ◽  
Granular Materials ◽  
Acoustic Properties ◽  
Log Normal

Effect of pore size distribution of ultrafiltration membranes on virus rejection in crossflow conditions

1994 ◽  
Vol 30 (9) ◽  
pp. 199-208 ◽  
Author(s):  
Taro Urase ◽  
Kazuo Yamamoto ◽  
Shinichiro Ohgaki
Keyword(s):  
Drinking Water ◽  
Pore Size Distribution ◽  
Pore Size ◽  
Size Distribution ◽  
Wastewater Reuse ◽  
Distribution Model ◽  
Water Supplies ◽  
Ultrafiltration Membranes ◽  
Molecular Weight Cutoff ◽  
Log Normal

The ultrafiltration process is successfully used in wastewater reuse systems. It will also be used widely in drinking water supplies. In wastewater reuse and for safer drinking water supplies the potential for virus rejection by membrane processes is advantageous. Rejection of viruses was examined experimentally by using coliphage Qβ as a tracer. Several types of ultrafiltration membranes with molecular weight cutoff size of 20,000-40,000 were tested. All of these membranes leaked phages to some extent, contrary to the expectation from nominal cutoff size. Penetration of virus through ultrafiltration membranes was theoretically examined by taking pore size distribution of the membranes into account. Modified pore theory and a log-normal pore size distribution model gave an unsatisfactory explanation of the results. The presence of abnormally large pores which are not included in the main distribution was indicated.

scholarly journals Fitting approach to liquid–liquid displacement porosimetry based on the log-normal pore size distribution

2014 ◽  
Vol 470 ◽  
pp. 219-228 ◽  
Author(s):  
Enrique Antón ◽  
José Ignacio Calvo ◽  
José R. Álvarez ◽  
Antonio Hernández ◽  
Susana Luque
Keyword(s):  
Pore Size Distribution ◽  
Pore Size ◽  
Size Distribution ◽  
Log Normal ◽  
Liquid Displacement

scholarly journals SWRC fit – a nonlinear fitting program with a water retention curve for soils having unimodal and bimodal pore structure

2007 ◽  
Vol 4 (1) ◽  
pp. 407-437 ◽  
Author(s):  
K. Seki
Keyword(s):  
Pore Size Distribution ◽  
Pore Size ◽  
Size Distribution ◽  
Soil Water ◽  
Water Retention ◽  
Distribution Model ◽  
Soil Water Retention ◽  
Nonlinear Fitting ◽  
Soil Hydraulic ◽  
Log Normal

Abstract. The soil hydraulic parameters for analyzing soil water movement can be determined by fitting a soil water retention curve to a certain function, i.e., a soil hydraulic model. For this purpose, the program "SWRC Fit," which performs nonlinear fitting of soil water retention curves to 5 models by Levenberg-Marquardt method, was developed. The five models are the Brooks and Corey model, the van Genuchten model, Kosugi's log-normal pore-size distribution model, Durner's bimodal pore-size distribution model, and a bimodal log-normal pore-size distribution model propose in this study. This program automatically determines all the necessary conditions for the nonlinear fitting, such as the initial estimate of the parameters, and, therefore, users can simply input the soil water retention data to obtain the necessary parameters. The program can be executed directly from a web page at http://purl.org/net/swrc/; a client version of the software written in numeric calculation language GNU Octave is included in the electronic supplement of this paper. The program was used for determining the soil hydraulic parameters of 420 soils in UNSODA database. After comparing the root mean square error of the unimodal models, the van Genuchten and Kosugi's models were better than the Brooks and Corey model. The bimodal log-normal pore-size distribution model had similar fitting performance to Durner's bimodal pore-size distribution model.

pyGAPS: A Python-Based Framework for Adsorption Isotherm Processing and Material Characterisation

2019 ◽  
Author(s):  
Paul Iacomi ◽  
Philip L. Llewellyn
Keyword(s):  
Pore Size Distribution ◽  
Pore Size ◽  
Size Distribution ◽  
Surface Area ◽  
Isosteric Heat ◽  
Material Characterisation ◽  
Mixture Adsorption ◽  
Surface Energetics ◽  
Adsorption Processing ◽  
User Friendly

Material characterisation through adsorption is a widely-used laboratory technique. The isotherms obtained through volumetric or gravimetric experiments impart insight through their features but can also be analysed to determine material characteristics such as specific surface area, pore size distribution, surface energetics, or used for predicting mixture adsorption. The pyGAPS (python General Adsorption Processing Suite) framework was developed to address the need for high-throughput processing of such adsorption data, independent of the origin, while also being capable of presenting individual results in a user-friendly manner. It contains many common characterisation methods such as: BET and Langmuir surface area, t and α plots, pore size distribution calculations (BJH, Dollimore-Heal, Horvath-Kawazoe, DFT/NLDFT kernel fitting), isosteric heat calculations, IAST calculations, isotherm modelling and more, as well as the ability to import and store data from Excel, CSV, JSON and sqlite databases. In this work, a description of the capabilities of pyGAPS is presented. The code is then be used in two case studies: a routine characterisation of a UiO-66(Zr) sample and in the processing of an adsorption dataset of a commercial carbon (Takeda 5A) for applications in gas separation.

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