The aim of the thesis is to develop a numerical model based on first principles for the simulation of change of size of soil pores during drying of soft soil. This model is suitable for the type of soil consisting of clay with layered structure, such as Montmorillonite. In this study, the geometry of the soil pore is idealized by a triangle consisting of three sand grains and clay fabrics conne...

For the case of flame thickness being of the order of the pore linear dimension, the flame structure and speed in adiabatic, premixed methane-air combustion in porous media are examined. The local, volume-averaged conservation equations that assume a local thermal equilibrium between the solid and the gas phases (i.e. the single-medium treatment) or allow for a thermal nonequilibrium (i.e. the ...

Mesoporous calcium-silicon xerogels with a pore size of 15 nm (MCS-15) and pore volume of 1.43 cm(3)/g were synthesized by using 1,3,5-mesitylene (TMB) as the pore-expanding agent. The MCS-15 exhibited good degradability with the weight loss of 50 wt% after soaking in Tris-HCl solution for 56 days, which was higher than the 30 wt% loss shown by mesoporous calcium-silicon xerogels with a pore si...

Compression and mercury intrusion porosimetry (MIP) tests were conducted to analyze the effect of municipal solid waste incineration fly ash (MSWIFA) content on mechanical performance pore structure geopolymer mortar. The MSWIFA weight contents 0%, 5%, 15%, 25%, 35% diameter distribution, specific surface area, volume considered assess mortars. popular fractal model was used investigate feature...

Mesoporous  MgO  microstructures  were  synthesized  using magnesium  acetate  tetrahydrate,  ammonium  oxalate  monohydrate and  Pluronic  F127  via  heating  at  40  °C  for  24  h  and  subsequent calcination. The mesoporous structure of magnesium oxide with the specific  surface  area  of  47m2 /g,  pore  volume  0.30  cm3 /g  and  the average pore size 24 nm is produced. According to ...

The carbon aerogels prepared by a new method through gelation and supercritical drying in isopropanol were characterized by X-ray photoelectron spectroscopy (XPS), scanning electron microscopy, and a surface area analyzer. Their chemical structure, morphology, and pore structure are discussed. We found that all of these carbon aerogel (CA-IPA) samples have almost the same carbon and oxygen elem...

The results of the interaction between coal failure and mining pressure field evolution during mining are presented. Not only the mechanical model of stope and its relative structure division, but also the failure and behavior characteristic of coal body under different mining stages are built and demonstrated. Namely, the breaking arch and stress arch which influence the mining area are quanti...

A nanopore is the ultimate analytical tool. It can be used to detect DNA, RNA, oligonucleotides, and proteins with submolecular sensitivity. This extreme sensitivity is derived from the electric signal associated with the occlusion that develops during the translocation of the analyte across a membrane through a pore immersed in electrolyte. A larger occluded volume results in an improvement in...

In polymer chromatography, chain molecules are separated by molecular weight, size, and chemical composition due to adsorption and exclusion in nanoporous substrates. Three regimes of separation are distinguished depending on the adsorption strength and the pore size. In the regime of size exclusion chromatography, the adsorption energy is weak and the separation is entropy-driven with larger m...