Underground rocks usually have complex pore system with a variety of pore types and a wide range of pore size. The effects of pore structure on elastic wave attenuation cannot be neglected. We investigated the pore structure effects on P-wave scattering attenuation in dry rocks by pore-scale modeling based on the wave theory and the similarity principle. Our modeling results indicate that pore ...

Nanoporous silicon powder was produced via efficient magnesiothermic reduction. In this work, the thermal effect and reduction process time were investigated on the porous silicon structure. The nanoporous silicon powders were characterized by  X-ray diffraction analysis and field emission scanning electron microscopy. The results demonstrate that porous structure was changed to homogeneous and...

Voltage-gated K+ channels contain a central pore domain and four surrounding voltage-sensing domains. How and where changes in the structure of the voltage-sensing domains couple to the pore domain so as to gate ion conduction is not understood. The crystal structure of KcsA, a bacterial K+ channel homologous to the pore domain of voltage-gated K+ channels, provides a starting point for address...

Supported catalysts synthesized via the interaction of Mg(OEt)2 with TiCl4 in the presence or absence of an internal stereoregulating donor (di-n-butyl phthalate), with different solvents (chlorobenzene, n-undecane, n-heptane) at different titanation temperatures have been studied by a set of physicochemical methods. Data on the chemical composition, X-ray structure and pore structure of these ...

the molecular sieves are selective adsorbents. they can adsorb some kind of molecules that are different in size or shape from the others. in separation of n-paraffins from iso-paraffins and aromatics, sa molecular sieve is the suitable adsorbent, and can adsorb n-paraffins to separate them from other hydrocarbons. in this paper equilibrium isotherms of n-cs, n-c6 and n-c7 from an inert solvent...

Powder activated carbon surface (AC) was grinded and modified and altered procedure thorough a facile and easy chemical reaction to appearance of 2-((3silylpropylimino)1-methyl) phenol (AC- (SPIMP)). Subsequently, this novel sorbent efficiently applied for the extraction and preconcentration of some metal ions from real samples. Preliminary the influences of variables such as pH, amounts of rea...

Bamboo-structured carbon nanotubes are grown on Co-Mo/MCM-41 catalyst in the temperature range of 873-973 K by thermal chemical vapor deposition of acetylene. This study shows that the purified carbon nanotubes have open tips and the metals of the catalyst are not encapsulated. Thus, the bamboo-structure seems to grow from the base. Pore size distribution of the product is quite narrow and ...

In this study, Santa Barbara Amorphous (SBA-15) mesoporous silica has been functionalized with aminopropyl groups that were converted to propargyl-bearing moieties through the reaction with propargyl bromide. The material then underwent an efficient Cu(I)-catalyzed azide alkyne click reaction with sodium azide in order to obtain the corresponding triazole products. The covalent modification of ...

Continuous filtration of fine particles involves filter cake formation and removal of surface moisture by drawing air through the pore structure network. Conventional network theory can be use to study the phenomena of flow through a porous structure by treating the pores as discrete volumes and connecting these with pore throats as resistances of zero volume. In this regard, analysis of the po...