The activity coefficient of aqueous silica was determined at 800 C and 12 kbar by measuring the concentration of total dissolved aqueous silica (SiO2(t)) in H2O in equilibrium with four buffering mineral assemblages: quartz (Q), kyanite–corundum (KC), enstatite–forsterite (EF), and forsterite–rutile–geikielite (FRG). SiO2(t) concentrations were determined by reversed equilibration of synthetic ...

A silica-supported copper (Cu/SiO2) catalyst containing highly dispersed Cu nanoparticles was prepared via a crown-ether-assisted impregnation method. 12-crown-4-ether-assisted Cu/SiO2 outperformed several catalysts with various organic additives in the dehydrogenation of 2,3- and 1,4-butanediol. It found that catalytic activity, i.e., formation rate acetoin from 2,3-butanediol γ-butyrolactone ...

Shape-preserving conversion offers a promising strategy to transform self-assembled structures into advanced functional components with customizable composition and shape. Specifically, the assembly of barium carbonate nanocrystals amorphous silica nanocomposites (BaCO3/SiO2) plethora programmable three-dimensional (3D) microscopic geometries, can subsequently be converted chemical compositions...

Sericin-derived oligopeptides obtained from silk cocoons were investigated for the in vivo hypotensive effect and investigated for the underlying mechanism involved in vasodilation in isolated rat thoracic aorta. In normotensive anesthetized rats, oligopeptides induced an immediate and transient hypotensive activity. In rat aortic rings, oligopeptides induced a concentration-dependent vasorelax...

Zwitterionic phosphocholine (PC) lipids are highly biocompatible, representing a major component of the cell membrane. A simple mixing of PC liposomes and silica (SiO2) surface results in liposome fusion with the surface and formation of supported lipid bilayers. However, the stability of this bilayer is relatively low because adsorption is based mainly on weak van der Waals force. PC lipids st...

Copper catalysts supported on silica or silica-alumina are used to promote the insertion of carbenes, coming from methyl phenyldiazoacetate and ethyl diazoacetate, into one C-H bond of THF, constituting the first example of this reaction promoted by a purely inorganic catalyst. Cu/SiO2-Al2O3 leads to better results, regarding yield and catalyst recovery, than with Cu/SiO2. With the former catal...

Hierarchical porous silica-supported nickel catalysts modified with different amounts of lanthanum (La) were synthesized via “one-pot” method using cetyltrimethylammonium bromide as template, urea precipitant, and tetraethyl orthosilicate silica source. Their catalytic performances evaluated in dry reforming methane under conditions (La loading, reaction temperature, time on stream). The spent ...

TiO2/SiO2 nanocomposite with molar ratio 1:1 was synthesized by a free calcination sol-gel method using titanium tetra chloride and tetraethylorthosilicate as raw materials. In the composite, TiO2 nanocrystals are highly dispersed in the amorphous SiO2 matrix and the mater showed size quantization effect arising from the presence of extremely small titanium oxide species having a low coordinati...

This paper describes the low temperature synthesis of belite (β-C2S) from silica fume. Mixtures of lime, BaCl2, and silica fume with the ratio of (Ca + Ba)/Si = 2 were hydrothermally treated in stainless steel capsule at 110-150°C for 2-5 hours, calcined at 600-700°C for 3 hours, and analyzed by FTIR, XRD, TGA/DTA, and SEM techniques. Dicalcium silicate hydrate (hillebrandite) was prepared by h...

Development of efficient catalysts for the direct hydrogenation CO2 to methanol is essential valorization this abundant feedstock. Here we show that a silica-supported Cu/Mo2CTx (MXene) catalyst achieves higher intrinsic formation rate per mass Cu than reference Cu/SiO2 with similar loading. The interface can be engineered due affinity partially reduced MXene surface (in preference SiO2 surface...