The transport of gases in porous materials is a crucial component of many important processes in science and technology. In the present work, we demonstrate how magnetic resonance microscopy with continuous flow laser-polarized noble gases makes it possible to "light up" and thereby visualize, with unprecedented sensitivity and resolution, the dynamics of gases in samples of silica aerogels and...

The number and the strength of acid sites in catalysts have paramount importance on their efficiency. In zeolites chemistry, increased content framework Al gives a higher strong sites. Their can be disadvantage catalytic reactions (e.g., methanol to olefins conversion) due undesired secondary coke formation. Here, Faujasite type zeolite with has been used for investigating role defects structur...

NaY zeolites with different framework Si/Al ratios were synthesized via hydrothermal technique. Structural characteristics of the synthesized zeolites were determined by using XRD, XRF, SEM, BET analyses. The effects of operating conditions of hydrothermal dealumination, i.e. time, temperature and partial pressure of water vapor on dealumination of the Y zeolites framework and their structure w...

Nanosized zeolite crystals (nanozeolites) with narrow particlesize distributions and sizes less than 100 nm have received much attention because of their great potential applications in catalysis and adsorption. The decrease in the crystal sizes results in high external surface areas, reduced diffusion path lengths, and more exposed active sites. For example, small Y-type zeolite crystals have ...

A ZSM-5 molecular sieve composite with a wide pore prepared by the solid phase in-situ synthesis method and fluid catalytic cracking, an FCC catalyst additive same for increasing amount of light olefin yield were investigated. The samples characterized XRD, N2 adsorption/desorption, SEM, NH3-TPD, respectively. results showed that structure was pure MFI-type zeolite material. crystallinity 59.8 ...

One-part geopolymers were synthesized from two different silica materials (a silica-rich residue from chlorosilane production and a commercial microsilica) and sodium aluminate at three different SiO2/Al2O3 ratios and a nominal water/solids ratio of 0.5. The degree of reaction of the silica in the cured geopolymers (i.e. the fraction of silica dissolved to form aluminosilicates and minor produc...

(1) Background: The tomato leafminer Tuta absoluta (Lepidoptera: Gelechiidae) is a key tomato insect pest. At present, it is considered to be a serious threat in various countries in Europe, North Africa, and Middle East. The extensive use and the developed resistance of T. absoluta to spinosad causes some concern, which leads to the need for alternative products. (2) Materials and Methods: Sev...

A direct comparison of quasielastic neutron scattering experimental measurements and molecular dynamics computer simulations is carried out for the first time for hydrogen and deuterium confined in the nanostructure of faujasite type zeolites at a temperature of 100 K, in order to investigate the dependence of sorption thermodynamics and sorbate dynamics on the sorbed phase concentration. The c...