Loose particulate materials can be problematic in various aspects. For example, loose particulate materials may generate dust or be difficult to consolidate together. Fines in loose particulate materials may also be an issue. Coated particulates may alleviate some of the foregoing issues. Suitable coated particulates may comprise a particulate material comprising sand or a ceramic, and a polysaccharide composition coated upon the particulate material, the polysaccharide composition comprising a functionalized polysaccharide. Other particulate materials such as wood chips and animal litter particulates may be coated with functionalized polysaccharides to achieve similar advantages.

A cubic boron nitride particle population having highly-etched surfaces and a high toughness index is produced by blending a reactive metal powder with a plurality of cubic boron nitride particles to form a blended mixture. The blended mixture is compressed to form a compressed mixture. The compressed mixture is subjected to a temperature and a pressure, where the temperature is controlled to cause etching of the plurality of cubic boron nitride particles by reaction of cubic boron nitride with the reactive metal powder, thereby forming a plurality of etched cubic boron nitride particles. Also, the temperature and pressure are controlled to cause boron nitride to remain in a cubic boron nitride phase. Afterwards, the plurality of etched cubic boron nitride particles is recovered from the compressed mixture to form the particle population. Preferably, the particle population contains no hexagonal boron nitride.

A cubic boron nitride particle population having highly-etched surfaces and a high toughness index is produced by blending a reactive metal powder with a plurality of cubic boron nitride particles to form a blended mixture. The blended mixture is compressed to form a compressed mixture. The compressed mixture is subjected to a temperature and a pressure, where the temperature is controlled to cause etching of the plurality of cubic boron nitride particles by reaction of cubic boron nitride with the reactive metal powder, thereby forming a plurality of etched cubic boron nitride particles. Also, the temperature and pressure are controlled to cause boron nitride to remain in a cubic boron nitride phase. Afterwards, the plurality of etched cubic boron nitride particles is recovered from the compressed mixture to form the particle population. Preferably, the particle population contains no hexagonal boron nitride.

Disclosed herein are coated gemstones, coatings for gemstones, methods of coating gemstones, and methods of using coatings on gemstones to avoid blemishes on gemstones. In some embodiments, diamonds are functionalized with anchor molecules that bind hydrophilic cyclodextrin molecules to confer hydrophilicity on the diamond. In some embodiments, the diamonds resist dirt and grime build-up.

A gas turbine engine article includes a substrate and a silicate-resistant barrier coating disposed on the substrate. The silicate-resistant barrier coating has an engineered microstructure that includes a refractory matrix formed of grains and calcium aluminosilicate additive (CAS additive) dispersed in grain boundaries between the grains.

A gas turbine engine article includes a substrate and a silicate-resistant barrier coating disposed on the substrate. The silicate-resistant barrier coating has an engineered microstructure that includes a refractory matrix formed of grains and calcium aluminosilicate additive (CAS additive) dispersed in grain boundaries between the grains.

A reaction-bonded silicon carbide (SiC) body is produced by: providing a preform including ceramic elements and carbon, and one or more surface features; providing a powder which includes diamond particles and carbon; locating the powder in the surface feature(s); and infiltrating the preform and the powder with molten silicon (Si) to form reaction-bonded SiC in the preform, and to form reaction-bonded SiC coatings on the diamond particles. The present disclosure also relates to a device/component which includes: a main body portion and discrete elements located at least partially within the main body portion. The main body portion may include reaction-bonded SiC and Si, but not diamond, while the discrete elements include diamond particles, reaction-bonded SiC coatings surrounding the diamond particles, and Si. According to the present disclosure, diamond may be advantageously located only where it is needed.

An article may include a substrate including a ceramic or a ceramic matrix composite. The substrate defines a hot side surface configured to face a heated gas environment and a cool side surface opposite the hot side surface. The article also includes a cool side coating on the cool side surface. The cool side coating comprises at least one material having a flow temperature equal to or slightly less than a temperature of the heated gas environment.

The present disclosure provides systems and methods for forming a composite structure comprising rotating a base layer of an apparatus for forming the composite structure about an axis of rotation, transferring carbon short fibers from a first vibratory feed ramp onto the base layer in order to form a plurality of fibrous layers in the composite structure, and vibrating the first vibratory feed ramp during the transferring the carbon short fibers. The base layer may comprise an annular shape.

The present disclosure relates to an apparatus for fluidised-bed chemical vapour deposition from a gaseous phase allowing the temperature of the fluidised bed to be stabilised during the deposition and also to an associated method for its implementation, the apparatus being characterised in that it comprises a porous thermal insulator present in an inlet zone and configured to be passed through by the gaseous phase, said porous thermal insulator having an effective thermal conductivity at 20° C. less than or equal to 3.5 W.Math.m-1.Math.K-1.