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Purpose The paper aims to focus on modeling of combined mixed convection and volumetric radiation within a vertical channel using a hybrid thermal lattice Boltzmann method (LBM). The multiple relaxation time LBM (MRT-LBM) is used to compute the dynamical field. The thermal field is determined by a finite difference method (FDM), and the simple relaxation time-LBM (SRT-LBM) serves to calculate the radiative part. The geometry considered concerns a vertical channel defined by two diffuse and isothermal walls. The active fluid represents a gray gas participating in absorption, emission and isotropically scattering. The parametrical study conducted aims to highlight the effect of Richardson number (Ri), Planck number (Pl) and the optical thickness (τ) on dynamical and thermal fields. It is found that radiation affects greatly heat transfer.Design/methodology/approach MRT-LBM is used to compute the dynamical field. The thermal field is determined by FDM, and SRT-LBM serves to calculate the radiative part.Findings This study has shown the strong capability of this approach to simulate similar problems. The Planck number largely affects the streamlines and isotherms distribution. Also, it causes disappearance of reversal flow, undesirable in most industrial applications, for low Planck numbers. The optical thickness causes the disappearance of reversal flow, in the case in which it appears, for lower opacity. However, for higher opacity it leads to a recurrence of reversed flow.Originality/value The use of a new original method composed of MRT-LBM to solve the fluid velocity, FDM to handle the temperature equation and extended SRT-LBM to compute the radiative part of the energy equation. [ABSTRACT FROM AUTHOR]

New research from the University of California San Diego (UCSD) describes the synthesis and characterization of self-assembled metalorganic framework monolayers (SAMMs) using polymer-coated particles. Metal-organic frameworks (MOFs) are materials with potential applications in fields such as gas adsorption and separation, catalysis, and biomedicine. By grafting polymers to the external surface of MOFs, issues of incompatibility between polymers and MOFs can be overcome, allowing for the formation of SAMMs. The methods presented in this research are expected to make the preparation of SAMMs more accessible to the research community and expand their potential use as a MOF-polymer composite. [Extracted from the article]

A report from the Chinese Academy of Sciences discusses the use of infrared multispectral imaging technology for the detection of target gases. The researchers propose an inversion method for gas column concentration based on this technology, which allows for the quantitative detection of gas concentration in complex environments. Experiments were conducted in different environments, and the results showed an average relative error of 4.84% in the inversion of gas column concentration. This research provides valuable insights into the application of imaging technology in the fields of dangerous-gas detection and environmental monitoring. [Extracted from the article]

An abstract of the article "Physisorption of gases, with special reference area to the evaluation of surface area and pore size distribution" by Matthias Thommes and colleagues is presented.