MSU-S mesoporous catalyst with [SiO2]/[Al2O3] ratio of 55 was synthesized using tetrapropylammonium hydroxide (TPAOH) as a structure directing agent and hexadecyltrimethylammonium bromide (CTAB) as a surfactant. The catalytic activity of the calcined sample was evaluated for the dehydration of methanol to dimethyl ether (DME) in a vertical fixed bed microreactor...

Nanopore silicalite type membranes were prepared on the outer surface of a porous-mullite tube by in situ liquid phase hydrothermal synthesis. The hydrothermal crystallization was carried out under an autogenously pressure, at a static condition and temperature of 180 °C with tetrapropylammonium bromide (TPABr) as a template agent. The molar composition of the starting gel of silicalite zeolite...

A new polymorph crystalline silica composition having uniform pore dimensions were synthesized by calcining a crystalline hydrated alkyl-ammonium silicate. The pore dimensions approximately were 6 angstrom for silicalite-1 and 11 angstrom for silicalite-2 units. The silicalite-1 was prepared hydrothermally at a pH of about 10 from a reaction mixture consist of water, amorphous silica and a ...

msu-s mesoporous catalyst with [sio2]/[al2o3] ratio of 55 was synthesized using tetrapropylammonium hydroxide (tpaoh) as a structure directing agent and hexadecyltrimethylammonium bromide (ctab) as a surfactant. the catalytic activity of the calcined sample was evaluated for the dehydration of methanol to dimethyl ether (dme) in a vertical fixed bed microreactor at a weight hurly space velocity...

Copolymers of methyl methacrylate and aryl-triazole based anion receptors were quantitatively analyzed. Transfer of structural features (1 : 1 and 2 : 1 complexes) and Cl(-) affinities from the parent receptors was demonstrated. Cl(-)-induced cross-linking changed the polymer's hydrodynamic radius. Extraction of tetrapropylammonium Cl(-) from water to dichloromethane was enhanced over PMMA.

The action of a tetrapropylammonium hydroxide solution on lamellar zeolite precursor MCM-22P produced a stable aqueous colloidal suspension which was shown by X-ray diffraction, small angle X-ray scattering and atomic force microscopy to contain ultrathin two-dimensional (2D) crystallites, including one-unit cell thick (i.e., 2.5 nm) monolayers.

The effects of 0.3-10 nM extracellular protons (pH 9.5-8.0) on ouabain-sensitive rubidium influx were determined in 4,4'-diisocyanostilbene-2, 2'-disulfonate (DIDS)-treated human and rat erythrocytes. This treatment clamps the intracellular H. We found that rubidium binds much better to the protonated pump than the unprotonated pump; 13-fold better in rat and 34-fold better in human erythrocyte...

(27) Al 3Q MAS NMR and UV/Vis spectroscopy with bare Co(II) ions as probes of Al pairs in the zeolite framework were employed to analyze the location of framework Al atoms in the channel system of zeolite ZSM-5. Furthermore, the effect of Na(+) ions together with tetrapropylammonium cation (TPA(+)) in the ZSM-5 synthesis gel on the location of Al in the channel system was investigated. Zeolites...