Mesoporous nanostructured γ-Al2O3 powders were synthesized through multi- step precipitation procedures using the pH-swing technique. Structural and morphological characteristics in addition to the thermal behavior of the procured samples were characterized via X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), fourier transform infrared (FT-IR) ...

Mesoporous nanostructured γ-Al2O3 powders were synthesized through multi- step precipitation procedures using the pH-swing technique. Structural and morphological characteristics in addition to the thermal behavior of the procured samples were characterized via X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), fourier transform infrared (FT-IR) ...

in this work, a tracer study on pore initiation in anodic alumina in oxalic acid was performed. effects of some experimental parameters such as applied electrical potential, electrolyte composition and heat pretreatment were evaluated. electrochemical and morphological experiments were performed using potentiostatic anodizing and scanning electron microscopy (sem) techniques, respectively. effe...

Signal-mediated nuclear transport is a gated process that occurs through a central transporter element located within the pore complex. The purpose of this investigation was to identify the region of the transporter that functions as the gate; i.e. the region that restricts passive diffusion of macromolecules through the pores. To accomplish this, small gold particles coated with polyethylene g...

In this study, in situ strength of concrete was determined through compression test of cores drilled out from laboratory cast beams. The apparent porosity and pore size distribution of the same concrete were determined through mercury intrusion porosimetry, performed on small-drilled cores. The normal-strength concrete mixes used in the experimental investigation were designed to exhibit a wide...

Reconstructing a pore size distribution of porous materials is valuable for applications in materials sciences, oil well logging, biology, and medicine. The major drawback of NMR based methods is an intrinsic limitation in the reconstruction which arises from the ill-conditioned nature of the pore size distribution problem. Consequently, while estimation of the average pore size was already dem...

Due to its excellent mechanical properties and ultra-lightweight, Al-based foam with homogeneous small pore-structures has wide applicational prospects in many industrial fields. However, during the foaming process of molten Al, it is difficult manipulate pore structures by means ALPORAS© production route due violent gas-releasing performance TiH2 as a traditional agent. Herein, we developed me...

The critical Rayleigh number for convective flow of pore water through a permeable spherical body is derived. The result affords constraints on carbonaceous chondrite planetesimal sizes and rates of heat production. If the chemical compositions of carbonaceous chondrites are taken as evidence against flow of pore water, then the present calculations suggest that the parent bodies were less than...

We report on the fabrication and electrical characterization of functionalized solid-state nanopores in low stress silicon nitride membranes. First, a pore of approximately 50 nm diameter was drilled using a focused ion beam technique, followed by the local deposition of silicon dioxide. A low-energy electron beam induced the decomposition of adsorbed tetraethyl orthosilicate resulting in site-...

s-doped and bare mesoporous tio2 were prepared using titanium tetraisopropoxide and thiocarbamide as raw materials. prepared materials were characterized by means of fourier transform infrared spectroscopy ft-ir, thermogravimetry-differential scanning calorimetry (tg-dsc), x-ray diffraction (xrd), uv–vis absorption spectroscopy, brunauer–emmett–teller (bet) specific surface area and barrett–joy...