D. H. Everett

Bio: D. H. Everett is an academic researcher. The author has contributed to research in topics: Adsorption & BET theory. The author has an hindex of 5, co-authored 6 publications receiving 4083 citations.

Recommendations for the characterization of porous solids (Technical Report)

Abstract: These recommendations aim to be a tool for the selection and appraisal of the methods of characterization of porous solids, and to also give the warnings and guidelines on which the experts generally agree. For this purpose, they successively consider the description of a porous solid (definitions, terminology), the principal methods available (stereology , radiation scattering, pycnometry, adsorption, intrusion, suction, maximum buble pressure, fluid flow, immersion or adsorption calorimetry, thermoporometry , size exclusion chromatography, Xenon NMR and ultrasonic methods) and finally the general principles which are worth being followed in the selection of the appropriate method.

Reporting Physisorption Data for Gas/Solid Systems

Abstract: The sections in this article are Introduction General Definitions and Terminology Methodology Methods for the Determination of Adsorption Isotherms Operational Definitions of Adsorption Experimental Procedures Outgassing the Adsorbent Determination of the Adsorption Isotherm Evaluation of Adsorption Data Presentation of Primary Data Classification of Adsorption Isotherms Adsorption Hysteresis Determination of Surface Area Application of the BET Method Empirical Procedures for Isotherm Analysis Assessment of Mesoporosity Properties of Porous Materials Application of the Kelvin Equation Computation of Mesopore Size Distribution Assessment of Microporosity Terminology Concept of Surface Area Assessment of Micropore Volume General Conclusions and Recommendations Keywords: physisorption data; IUPAC; adsorption isotherms; surface area; BET isotherm

Guidelines for the Characterization of Porous Solids

Abstract: The aim of this paper is to give an impression of the work of the recently disbanded IUPAC Sub-Committee on the Characterization of Porous Solids. It provides a brief description of the development, content and philosophy of the Recommendations of the Sub-Committee, to be published in Pure and Applied Chemistry. An outline is given of the terminology required to define a porous solid and of the proposed general guidelines for the selection of the most appropriate methods of characterization.

The SCI/IUPAC/NPL project on surface area standards

Abstract: Values of the nitrogen BET specific surface areas calculated from data supplied by many laboratories on four currently available surface area standards are presented and compared. Analytical data, representative adsorption isotherms and typical BET plots are given. Various factors affecting the accuracy of nitrogen BET surface area measurements are summarised.

Gas adsorption characterization of ordered organic-inorganic nanocomposite materials

Abstract: A critical review of adsorption methods that are currently used in the characterization of ordered organic−inorganic nanocomposite materials is presented, and the adsorption methodology that is potentially useful for this characterization, but has not yet been applied, is discussed. The ordered organic−inorganic nanocomposites include surface-functionalized ordered mesoporous materials (OMMs) with siliceous frameworks (synthesized either via postsynthesis surface modification or via direct co-condensation method), periodic mesoporous organosilicas, and surfactant-containing OMMs. This review covers the methods for determination of the specific surface area and pore volume. The available methods for mesopore size analysis are critically compared and evaluated, with special emphasis on the recent developments related to the application of advanced computational methods for studying adsorption in porous media and to the direct modeling of adsorption using highly ordered surface-functionalized OMMs as model a...

The structural and luminescence properties of porous silicon

Abstract: A large amount of work world-wide has been directed towards obtaining an understanding of the fundamental characteristics of porous Si. Much progress has been made following the demonstration in 1990 that highly porous material could emit very efficient visible photoluminescence at room temperature. Since that time, all features of the structural, optical and electronic properties of the material have been subjected to in-depth scrutiny. It is the purpose of the present review to survey the work which has been carried out and to detail the level of understanding which has been attained. The key importance of crystalline Si nanostructures in determining the behaviour of porous Si is highlighted. The fabrication of solid-state electroluminescent devices is a prominent goal of many studies and the impressive progress in this area is described.

Spectrum of pore types and networks in mudrocks and a descriptive classification for matrix-related mudrock pores

Abstract: Matrix-related pore networks in mudrocks are composed of nanometer- to micrometer-size pores. In shale-gas systems, these pores, along with natural fractures, form the flow-path (permeability) network that allows flow of gas from the mudrock to induced fractures during production. A pore classification consisting of three major matrix-related pore types is presented that can be used to quantify matrix-related pores and relate them to pore networks. Two pore types are associated with the mineral matrix; the third pore type is associated with organic matter (OM). Fracture pores are not controlled by individual matrix particles and are not part of this classification. Pores associated with mineral particles can be subdivided into interparticle (interP) pores that are found between particles and crystals and intraparticle (intraP) pores that are located within particles. Organic-matter pores are intraP pores located within OM. Interparticle mineral pores have a higher probability of being part of an effective pore network than intraP mineral pores because they are more likely to be interconnected. Although they are intraP, OM pores are also likely to be part of an interconnected network because of the interconnectivity of OM particles. In unlithifed near-surface muds, pores consist of interP and intraP pores, and as the muds are buried, they compact and lithify. During the compaction process, a large number of interP and intraP pores are destroyed, especially in ductile grain-rich muds. Compaction can decrease the pore volume up to 88% by several kilometers of burial. At the onset of hydrocarbon thermal maturation, OM pores are created in kerogen. At depth, dissolution of chemically unstable particles can create additional moldic intraP pores.