The filling of halloysite nanotubes with active compounds solubilized in aqueous solvent was investigated theoretically and experimentally. Based on Knudsen thermogravimetric data, we demonstrated the water confinement within the cavity of halloysite. This process is crucial to properly describe...

Halloysite and its heating products demand attention due to its multiple technological applications, and in particular for its natural nanostructure. The purpose of this paper is to present a structural characterization of these materials and its firing products up to mullite. To achieve this ob...

Lithium disilicate glass-ceramic in the Li2O–SiO2–Al2O3–K2O–P2O5 system has been investigated by incorporation of ZrO2. The influence of ZrO2 on phase formation, microstructure, biaxial flexural strength and translucency were determined. Investigations were carried out by means of differenti...

The objective of the study was to analyze the nucleation, primary phase formation and solid state reaction to form lithium disilicate glass–ceramics derived from the SiO2–Li2O–Al2O3–K2O–ZrO2–P2O5 system. The concentration of P2O5 was increased from zero up to 3.2 wt%. Thermal analysis, sca...

The purpose of this study was the synthesis of lithium disilicate glass-ceramics in the system SiO2–Al2O3–K2O–Li2O. A total of 8 compositions from three series were prepared. The starting glass compositions 1 and 2 were selected in the leucite–lithium disilicate system with leucite/lithium d...

In the present study, the crystallization principles and phenomena of base glasses from the system of SiO2-Li2O-P2O5-Al2O3-K2O-Nb2O5 or Ta2O5 were investigated. Annealing parameters such as temperature and time were varied. Annealing the base glasses 10 min at temperatures

In order to improve the mechanical properties, a traditional physical strengthening process was applied to a lithium disilicate (LD) glass-ceramic with a dual-phase microstructure consisting of a glassy matrix and LD crystals. The strengthening process was based on the transformation behavior of...

Potassium disilicate (K2Si2O5) glasses substituted with additions of Ca2+ and Al3+ have been prepared, characterized and tested as diesel soot oxidation catalysts. Ca and Al modify the silicate glass network, resulting in improved stability for catalyzing oxidation of diesel soot. TGA and water ...

Post-crystallization annealing above the Tg was applied to a lithium disilicate glass-ceramic with microstructure consisting of glassy matrix and rod-like lithium disilicate crystals, effect of the annealing on the mechanical behavior was investigated. Flexural strength and VIF toughness of the ...

A calcium-magnesium aluminosilicate (CMAS) glass was prepared by melting a sample of desert sand to evaluate the high-temperature interactions between molten CMAS and yttrium disilicate (Y2Si2O7), an environmental barrier coating (EBC) candidate material. Cold-pressed pellets of 80 wt% Y2Si2O7 p...

Statement of problemLittle information is available for the strength of bonding between zirconia and lithium disilicate as affected by surface pretreatment methods.

This study aimed to evaluate the mechanical and bioactive performances of lithium disilicate glass-ceramic mixtures produced from the SiO2-Li2O-ZrO2-K2O-P2O5-Al2O3 system by sol-gel and melting methods. The microstructure and constituent of the samples were characterized by XRD, FTIR, SEM and ED...

To solve the conundrum of percolative dielectric composites, namely, large dielectric loss caused by direct contact between conductive fillers near the percolation threshold, researchers introduced a general method of coating an insulative shell on the conductive fillers. In this work, a core–s...

The chromatographic characteristics of amino acids, peprides, amino sugars, aliphatic mono- and polyamines on ready-for-use plates of RP-18 and SIL C18-50 untreated or impregnated with dodecylbenzensulphonic acid and on layers of ammonium and tetramethylammonium tungstophosphate have been invest...

RP-HPLC coupled with 16-channel coulometric electrode array detection was used to monitor the decomposition of five amino acid o-phthalaldehyde (OPA)3̄sulfite derivatives (Ala, Arg, Glu, Ser, Tyr) and their methyl ester derivatives as well. At fixed OPA and sulfite concentrations inclusion of me...

Composite sodium p-toluenesulfonate/polypyrrole/TiO2 nanotubes/Ti was designed and synthesized for sodium ion battery anode via facile electrochemical methods. The obtained composite sodium p-toluenesulfonate/polypyrrole/TiO2 nanotubes/Ti (TsONa/PPy/TiO2NT/Ti) electrode was investigated in terms...

A 12-phosphotungstic acid (PTA)-based esterification catalyst was prepared by modifying PTA with 1,2,3-trizaole-4,5-dicarboxylic acid (TDA). The obtained TDA-PTA sample was characterized with XRD, IR, SEM, TG and potentiometric titration techniques, and its catalytic properties for esterificatio...

Extractive-catalytic oxidative desulfurization (ECOD) technology is a potential industrial application for attaining low-sulfur fuel oils. In this research, novel graphene oxide (GO)-based heterogeneous catalysts were synthesized by immobilization of different amounts of phosphotungstic acid H3P...

MnFe2O4@SiO2@NHPhNH2–phosphotungstic acid was synthesized by the reaction of diamine-modified silica coated manganese ferrite nanoparticles with H3PW12O40, the Keggin-type heteropoly acid. This is the first time that H3PW12O40 supported on diamine functionalized MnFe2O4 nanoparticles has been r...

This article proposes a novel strategy for producing highly dispersed H3PW12O40 (HPW) on metal-organic frameworks (MOFs) via the anchoring action of amino groups originating from 2-amino terephthalic acid (APTA) in the MOF ligand. Under this method, amino groups are introduced into the linker of...