Disclosed herein are fire resistant compositions and articles, for example, in the form of boards, insulation, sheeting, blocks, panels and similar materials of construction. Also disclosed are methods of preparing fire resistant compositions and articles and methods of use thereof.

A process is provided for treating raw fly ash used in cementitious material so as to increase the strength of the cementitious material while at the same time providing a near linear strength increase for the material as it cures by processing the raw fly ash, as by milling, and by mixing the processed fly ash with a catalyst such as lithium, with the lithium concentration in the fly ash being between 0.05% and 0.25% by weight. The process applies to Class C fly ash and Class F fly ash when mixed with Class C fly ash. All of the above processes include the use of polycarboxylates.

Embodiments relate to cementing operations and, in certain embodiments, to passivated cement accelerators and methods of using passivated cement accelerators in subterranean formations. An embodiment may comprise a method of cementing comprising: providing a cement composition comprising cement, water, and a passivated cement accelerator; and allowing the cement composition to set.

Embodiments relate to cementing operations and, in certain embodiments, to passivated cement accelerators and methods of using passivated cement accelerators in subterranean formations. An embodiment may comprise a method of cementing comprising: providing a cement composition comprising cement, water, and a passivated cement accelerator; and allowing the cement composition to set.

This disclosure describes formulations and methods for dust control, for example, coal topping, a term which refers to the application of liquid products to the top of coal loads, such as those in open topped coal hopper railcars as commonly used today to transport coal. Disclosed herein are asphalt-based emulsion formulations that accomplish dust control during industrial operations in which dust handling is required.

The invention provides novel methods and compositions that mitigate the occurrence of hazing of products made from carbonatable calcium silicate-based cements. The methods and compositions of the invention may be applied in a variety of cement and concrete components in the infrastructure, construction, pavement and landscaping industries.

A sulfate-resistant cement composition may contain calcium magnesium aluminum oxide silicate, brownmillerite, dolomite, periclase, and calcium aluminum oxide. The composition may contain the calcium aluminum oxide in an amount in the range of 0.01 to 2.0 wt. %. The composition may contain the brownmillerite in an amount of the range of 20 to 30 wt. %.

A precast concrete structure formed of a cementitious mixture is provided, the cementitious mixture comprising a mixture of: (a) cement, (b) silica fume, (c) supplemental material (limestone and/or slag), (d) masonry sand, (e) water and ice (f) plasticizers and (g) workability admixtures. The result is an improved concrete for use in the formation of long span bridge elements that are simple and safe to manufacture and having improved properties. The instant abstract is neither intended to define the invention disclosed in this specification nor intended to limit the scope of the invention in any way.

The present disclosure provides a composite including a nitride sintered body having a porous structure and a semi-cured product of a heat-curable composition impregnated into the nitride sintered body, wherein a dielectric breakdown voltage obtainable after disposing the composite between adherends, heating and pressurizing the composite for 5 minutes under the conditions of 200° C. and 10 MPa, and further heating the composite for 2 hours under the conditions of 200° C. and atmospheric pressure, is greater than 5 kV.

The present disclosure provides a composite including a nitride sintered body having a porous structure and a semi-cured product of a heat-curable composition impregnated into the nitride sintered body, wherein a dielectric breakdown voltage obtainable after disposing the composite between adherends, heating and pressurizing the composite for 5 minutes under the conditions of 200° C. and 10 MPa, and further heating the composite for 2 hours under the conditions of 200° C. and atmospheric pressure, is greater than 5 kV.