Abstract: A composition for use in making a structural assembly board, a structural assembly made from the composition, and a method of making the structural assembly board is provided. The composition includes magnesium oxide having purity of 94-98 wt %; magnesium chloride; fly ash; and water. The magnesium oxide has at least two different particles sizes. The composition and method of making the structural assembly board promote formation of 5MgO·MgCl2·8H2O to improve structural qualities of the structural assembly board.

Abstract: An environmentally acceptable leak sealant comprising lava rock aggregate (scoria) for sealing leaks in dams, holding ponds or other water-containing structures. The aggregate is selected and graded for particle size and density. Particles of different sizes cooperate to engage walls of the leak and interlock with each other to form a seal within a leak opening. The particles must sink at a suitable rate, and become entrained in water flow through the leak. Beneficially larger particles have a generally higher sink rate than smaller particles, and so arrive first at the leak to staunch a major part of the flow; intermediate and smaller particles follow to form an effective seal. Applications include sealing sluice gates, stop logs at hydroelectric dams to reduce water wastage for increased electricity productivity, for maintenance requiring de-watering of the turbine; or for sealing leaks in cracks in bedrock or concrete structures associated with dams.

Abstract: Despite the excellent properties associated with Magnesium OxyChloride (Sorel) based cements and Magnesium OxySulfate based cements, water and corrosion resistance has been limiting factors for achieving greater commercial applications. Such issues can be addressed by incorporating various alkali metal phosphates, such as Magnesium mono- or dihydrogen phosphate (MgHPO4 or MgH2PO4) with alkali metal fatty acids; such as Magnesium Stearate; and metal or alkali metal sulfates such as Aluminum Sulfate or Magnesium Sulfate. Water resistance is further enhanced by either pre-carbonating the mix water or the liquid magnesium chloride phase of the cements, or by adding a carbonate into the powder phase. Accelerated cure of this system has also been obtained by using various inorganic metal oxides. Additionally, improved corrosion resistance is achieved through the use of certain phosphates, zeolites, nitrites and other novel additives.

Abstract: Despite the excellent properties associated with Magnesium OxyChloride (Sorel) based cements and Magnesium OxySulfate based cements, water and corrosion resistance has been limiting factors for achieving greater commercial applications. Such issues can be addressed by incorporating various alkali metal phosphates, such as Magnesium mono- or dihydrogen phosphate (MgHPO4 or MgH2PO4) with alkali metal fatty acids; such as Magnesium Stearate; and metal or alkali metal sulfates such as Aluminum Sulfate or Magnesium Sulfate. Water resistance is further enhanced by either pre-carbonating the mix water or the liquid magnesium chloride phase of the cements, or by adding a carbonate into the powder phase. Accelerated cure of this system has also been obtained by using various inorganic metal oxides. Additionally, improved corrosion resistance is achieved through the use of certain phosphates, zeolites, nitrites and other novel additives.

Abstract: A magnesium oxychloride cement (MOC) composition comprising: caustic calcined magnesia magnesium chloride phosphoric acids or corresponding salts exfoliated vermiculite.

Abstract: A magnesium oxychloride cement (MOC) composition comprising: caustic calcined magnesia magnesium chloride phosphoric acids or corresponding salts exfoliated vermiculite.

Abstract: A slurry composition comprising an alkaline metal oxide, a chloride or phosphate salt, water, glass beads and a foaming agent. A foamed slurry comprising magnesium oxide, water, a chloride or phosphate salt, and glass beads, wherein the slurry has a density of from about 4 to about 12 pounds per gallon. A foamed slurry comprising magnesium oxide, water, a chloride or phosphate salt, and beads, wherein the slurry has a density of from about 4 to about 12 pounds per gallon and the set slurry is acid soluble.

Abstract: Magnesium oxychloride cement is formed by mixing a magnesium chloride (MgCl2) brine solution with a magnesium oxide (MgO) composition in a selected stoichiometric ratio of MgCl2, MgO, and H2O that forms the 5 phase magnesium oxychloride cement composition. Although Sorel cements formed from the mixture of MgCl2, MgO can form a variety of compounds, the inventive systems and methods provide for controlling the cement kinetics to form the five phase magnesium oxychloride cement composition and results in an improved and stable cement composition. Various fillers can be optionally added to form preferred cement materials for uses as diverse such as road stripping, fire-proofing, fire barriers, cement repair, and mortar.

Abstract: Magnesium oxychloride cement is formed by mixing a magnesium chloride (MgCl2) brine solution with a magnesium oxide (MgO) composition in a selected stoichiometric ratio of MgCl2, MgO, and H2O that forms the 5 phase magnesium oxychloride cement composition. Although Sorel cements formed from the mixture of MgCl2, MgO can form a variety of compounds, the inventive systems and methods provide for controlling the cement kinetics to form the five phase magnesium oxychloride cement composition and results in an improved and stable cement composition. Various fillers can be optionally added to form preferred cement materials for uses as diverse such as road stripping, fire-proofing, fire barriers, cement repair, and mortar.

Abstract: Novel hydraulic cements are disclosed that include reactive magnesium oxide prepared by low temperature calcination. The cements can be formulated to suit a large number of applications with various setting times, strength and levels of sustainability either by adding iron salts such as ferrous sulfate or blending with other compatible faster setting hydraulic cements such as Portland cement or by using both methods. The compositions are able to incorporate relatively large amounts of low cost pozzolans such as fly ash to advantage as well as wastes. Many excellent properties are exhibited and in particular good comprehensive strength and resistance to sulfates is able to be achieved.

Abstract: A two-layer coating for the outer surface of the display screen of a color cathode ray tube (CRT) includes an inner carbon black-based layer and an outer silica-based layer. The inner layer is antistatic, while the outer layer is antireflective. To compensate for the increased absorption of blue light by the carbon black particles, which results in a color video image having a yellowish tint, a blue additive, such as a pigment or dye, is added to the coating to adjust its light absorbance characteristics and provide uniform light absorbance over the entire visible spectrum of 400-700 nm for improved color video image presentation.

Abstract: Corrugated abrasive discs such as grinding wheels are treated by applying a water-resistant coating to the interiors of the corrugations before the corrugations are plugged. Discs having water-sensitive matrices such as magnesium oxychloride cement are thus protected against water or water vapor seepage from aqueous-based plug fill material.

Abstract: A cementitious material having improved resistance to water, increased strength, increased resistance to deteriorating processes and which is toxic to certain microorganisms and repellent to certain roach species, said material comprising on a dry mix basis, in % by weight, about 2% to 5% copper oxide, about 1% to 5% condensed silica fume, about 1.5% siloxane coated calcium hydroxide, about 53.5% to 60.5% dolomitic limestone and effective amounts of pigments and fillers.

Abstract: There are here disclosed carbon fibers for reinforcement of cement which are obtained by applying, onto the surfaces of carbon fibers, esters of oleic acid and aliphatic monovalent alcohols, esters of oleyl alcohol and monovalent fatty acids, polyoxyalkylene bisphenol ethers or polyether esters as sizing agents, and a cement composite material having a bending strength of 300 kgf/cm.sup.2 or more which contains cut carbon fibers having a fiber length of 10 to 50 mm at a mixing volume ratio of the cut carbon fibers to the cement matrix in the range of 1 to 5%. According to the present invention, there are provided the carbon fibers for reinforcement of cement which have excellent adhesive properties to the cement, good process passage properties through a direct spray gun and good bundling properties and which are suitable for a direct spray method, and the cement composite material using the carbon fibers and having high bending strength.

Abstract: In order to be able to produce formed elements or building elements with a significantly increased strength with a building material or structural material, it is suggested to provide the material with a largely uniform fine pore structure or a microcellular structure. These fine pores preferably have a diameter in the range of approx. 0.01.mu. to approx. 5.mu. and are self-contained. The material contains a reactive binding agent or a reactive matrix material, which can be a cement/water mixture or also a synthetic resin, for example polyurethane, epoxy resin, etc.

Abstract: Magnesium oxychloride cement bonds are improved by incorporation of graphite. The graphite not only contributes to cooler dry grinding with abrasive tools based on the magnesium oxychloride bond, but unexpectedly also improves heat strength of the bond.

Abstract: The structural part is used in an electolytic cell for production of aluminum and comes into contact with the gas atmosphere in the electrolytic reduction cell. The structural part is made completely from, or is a metal part which is coated with, a concrete composition of 15-30% by weight of a hydraulic cement, 5-10% by weight of microsilica and 65-85% by weight of a refractory filler material.

Abstract: Magnesite bonds reinforced with selected fibers have improved resistance to cracking and disintegration in use. Particular embodiments include fiber-reinforced abrasive tools based on magnesite bonds which have improved bond integrity in dry-grinding applications.

Abstract: Magnesium oxychloride cement bonds are improved by incorporation of graphite. The graphite not only contributes to cooler dry grinding with abrasive tools based on the magnesium oxychloride bond, but unexpectedly also improves heat strength of the bond.

Abstract: A process for producing a hard material from a cementitious mixture, the process including the steps of blending together a cement constituent and a filler constituent whilst in a dry condition to provide a compactable homogeneous mixture containing a predetermined volume of voids defined between filler particles up to a predetermined size, laying the dry mixture onto a substrate, sparingly applying water to the surface of the mixture to dampen the surface layer of the mixture for causing setting of the cement in said surface layer and subsequently applying more water for causing setting and hardening of the remainder of the cement.

Abstract: Low density well cement compositions which set into hard substantially impermeable masses, but which are removable by dissolution in acid, and methods of utilizing such compositions for forming removable cement plugs or seals in subterranean zones are provided. The compositions are comprised of pumpable foamed slurries of magnesium oxychloride cement.

Abstract: Retarded acid soluble well cement compositions which set into hard substantially impermeable masses and methods of using such compositions for forming removable cement plugs or seals in subterranean zones are provided. The compositions are comprised of magnesium oxychloride cement and a set retarder comprised of a water soluble borate and a sugar.

Abstract: Low density well cement compositions which set into hard substantially impermeable masses, but which are removable by dissolution in acid, and methods of utilizing such compositions for forming removable cement plugs or seals in subterranean zones are provided. The compositions are comprised of pumpable foamed slurries of magnesium oxychloride cement.

Abstract: A magnesium concrete which comprises magnesium oxide in about 100 parts; magnesium chloride in a range of about 40 to about 80 parts; mineral aggregates in a range of about 300 to about 500 parts; sublimates of carnallite chlorates in a range of about 20 to about 40 parts; and sodium siliceous-fluoride in a range of about 1 to about 2 parts.

Abstract: Process for making a cement mixture containing fibers wherein a paste is formed by mixing cement and, per 100 parts by weight of cement, approximately 5 to 20 parts by weight of a first pulverized material of which the grains have an average diameter of between 1/5 and 1/10 of the average diameter of the grains of the cement and approximately 20 to 35 parts by weight of water. The paste is then mixed with reinforcing fibers. The paste may also include a second pulverized material the average grain diameter of which is between 1/5 and 1/10 of the average diameter of the first pulverized material. The invention further includes products made from a cement mixture manufactured according to one of the foregoing processes.

Abstract: A discontinuous drawn steel wire fiber for incorporation in a fiber composite, in particular a cement material, the fiber being made from a length of steel wire which is shaped so that the fiber is contained in a plane and, in said plane, is in the configuration of a loop which is convex and closed, wherein it has the configuration of an oblong loop whose ends are delimited by curvilinear wire portions, said curvilinear wire portions being interconnected by rectilinear wire portions, and wherein the two end portions of said length of wire are disposed side by side and in opposite directions, said end portions extending between said curvilinear wire portions to form one of said rectilinear wire portions.

Abstract: A device comprising a solid or powdered concrete admixture contained in a water-soluble container such that when the container and its contents are introduced into a wet mixer and agitated for a period of time, the water-soluble container is dissolved and the contents are released into the wet mixer. A separate water-insoluble receptacle is used to house and store the water-soluble container and its contents. In addition, there is disclosed a method for modifying the properties of a concrete by introducing a pre-weighed amount of solid admixture contained in a water-soluble container into a wet mixer and thereafter agitating the resulting mix.

Abstract: Magnesium oxychloride cement compositions, products, and uses thereof, are provided by mixing magnesium oxide, a magnesium chloride solution, and aggregate particles. The cement compositions are adapted for use in repairing damaged concrete surfaces, casting both functional and decorative forms, and coating surfaces with stucco. The addition of a small amount of acid to the cement composition promotes a more complete cementing reaction. The resulting cement product exhibits substantially increased strength and water resistance. Brine from the Great Salt Lake is a preferable source of the magnesium chloride solution. Brine from the Great Salt Lake results in a cement composition substantially stronger than cement produced from a pure magnesium chloride solution. Use of the Great Salt Lake brine as the gauging solution in lieu of a gauging solution made from magnesium chloride flakes (hexahydrate) reduces manufacturing costs of magnesium oxychloride cement products.

Abstract: A settable magnesium cement composition, useful for floor leveling or for the preparation of molded products, has a two part mix. The first part includes magnesium oxide, while the second part includes magnesium chloride component and a particulate fibrous material compound, ideally a coarse, fibrous long-stranded sawdust, known as green fibrous sawdust, having a moisture content of about 40-50% by weight.

Abstract: Magnesium oxychloride cement compositions, products, and uses thereof, are provided by mixing magnesium oxide, a magnesium chloride solution, and aggregate particles. The cement compositions are adapted for use in repairing damaged concrete surfaces, casting both functional and decorative forms, and coating surfaces with stucco. The addition of a small amount of acid to the cement composition promotes a more complete cementing reaction. The resulting cement product exhibits substantially increased strength and water resistance. Brine from the Great Salt Lake is a preferable source of the magnesium chloride solution. Brine from the Great Salt Lake results in a cement composition substantially stronger than cement produced from a pure magnesium chloride solution. Use of the Great Salt Lake brine as the gauging solution in lieu of a gauging solution made from magnesium chloride flakes (hexahydrate) reduces manufacturing costs of magnesium oxychloride cement products.