Nitrogen Adsorption of Solvent-exchanged Wood Cellulose Fibers: Indications of “Total” Surface Area and Pore Size Distribution

The objective of this work was to examine the influence of carbonation on the microstructure of cement materials. Different materials, which were CEM I mortar and paste, CEM II mortar and paste, were carbonated at 20°C, 65% relative humidity and 20% of CO2 concentration. The specific surface area and pore size distribution were determined from the method of nitrogen adsorption. The results showed that the materials based on CEM II seemed to be more sensible to a creation of mesoporosity after carbonation than the CEM I based materials. The results of this study also helped to explain why observations in the literature diverge greatly on the influence of carbonation on specific surface area.

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

10.26434/chemrxiv.7970402.v1 ◽

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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Air filtration improvement of konjac glucomannan-based aerogel air filters through physical structure design

International Journal of Low-Carbon Technologies ◽

10.1093/ijlct/ctab011 ◽

2021 ◽

Author(s):

Hong Qian ◽

Ying Fang ◽

Kao Wu ◽

Hao Wang ◽

Bin Li ◽

...

Keyword(s):

Pore Size Distribution ◽

Pore Size ◽

Size Distribution ◽

Surface Area ◽

Physical Structure ◽

Structure Design ◽

Air Filtration ◽

Air Filters ◽

Air Filter ◽

Purification Time

Abstract This study presents two methods to improve the air filtration performance of konjac glucomannan (KGM)-based aerogel air filters through physical structure design by changing the pore-size distribution and the surface area, using an air purifier. Results indicated that KGM-based aerogels had a comparable filtration effect with the commercial air filter with a longer purification time. This purification time could be shortened by over 50%, by changing the pore-size distribution from large size to small size or increase the surface area with the fold structure. This should boost the development of polysaccharide-based aerogel used as the air filter.

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The relationship between geotechnical index properties and the pore-size distribution of compacted clayey silts

Science and Engineering of Composite Materials ◽

10.1515/secm-2013-0302 ◽

2015 ◽

Vol 22 (6) ◽

Author(s):

Nazile Ural

Keyword(s):

Specific Surface ◽

Pore Size Distribution ◽

Pore Size ◽

Size Distribution ◽

Surface Area ◽

Specific Surface Area ◽

Pore Volume ◽

Correlation Coefficients ◽

Liquid Limit ◽

Index Properties

AbstractIn this study, the relationships between geotechnical index properties and the pore-size distribution of compacted natural silt and artificial soil mixtures, namely, silt with two different clays and three different clay percentages (10%, 20%, and 40%), were examined and compared. Atterberg’s limit tests, standard compaction tests, mercury intrusion porosimetry, X-ray diffraction, scanning electron microscopy (SEM) analysis, and Brunauer-Emmett-Teller specific surface analysis were conducted. The results show that the liquid limit, the cumulative pore volume, and specific surface area of artificially mixed soils increase with an increase in the percentage of clay. The cumulative pore volume and specific surface area with geotechnical index properties were compared. High correlation coefficients were observed between the specific areas and both the liquid limit and the plasticity index, as well as between the cumulative pore volume and both the clay percentage and the

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ChemInform Abstract: The Use of Adsorption Methods for the Assessment of the Surface Area and Pore Size Distribution on Heterogeneous Catalysts

ChemInform ◽

10.1002/chin.199412340 ◽

2010 ◽

Vol 25 (12) ◽

pp. no-no

Author(s):

J. J. F. SCHOLTEN

Keyword(s):

Pore Size Distribution ◽

Pore Size ◽

Size Distribution ◽

Surface Area ◽

Heterogeneous Catalysts

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Characterisation of Low-K Dielectric Films by Ellipsometric Porosimetry

MRS Proceedings ◽

10.1557/proc-612-d4.2.1 ◽

2000 ◽

Vol 612 ◽

Cited By ~ 13

Author(s):

M.R. Baklanov ◽

K.P. Mogilnikov

Keyword(s):

Pore Size Distribution ◽

Pore Size ◽

Size Distribution ◽

Surface Area ◽

Average Pore Size ◽

Dielectric Films ◽

Swelling Properties ◽

Small Surface ◽

Ellipsometric Porosimetry ◽

Low K

AbstractEllipsometric porosimetry (EP) is a simple and effective method for the characterization of the porosity (volume of both open and close pores), average pore size, specific surface area and pore size distribution (PSD) in thin porous films deposited on top of any smooth solid substrat e. Because a laser probe is used, small surface area can be analyzed. Therefore, EP can be used on patterned wafers and it is compatible with microelectronic technology. This method is a new version of adsorption (BET) porosimetry. In situ ellipsometry is used to determine the amount of adsorptive which adsorbed/condensed in the film. Change in refractive index is used to calculate of the quantity of adsorptive present in the film. EP also allows the study of thermal stability, adsorption and swelling properties of low-K dielectric films. Room temperature EP based on the adsorption of vapor of some suitable organic solvents and method of calculation of porosity and PSD is discussed. Examination of the validity of Gurvitsch rule for various organic adsorptives (toluene, heptane, carbon tetrachloride and isopropyl alcohol) has been carried out to assess the reliability of measurements of pore size distribution by the ellipsometric porosimetry.

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