Abstract: A method of making an optically black surface having a low reflectance of electromagnetic radiation, especially in the solar spectrum, a relatively high heat resistance, and a relatively low amount of off-gassing and an optically black surface made by the method which includes the steps of(a) Milling the following mixture of ingredients for up to about 25 minutes:______________________________________ Ingredient Amount (% by weight) ______________________________________ Alkali metal silicate 13-21 Black pigment 17-27 Kaolin 0-5 Mica 0-3 Water 50-70 ______________________________________(b) Coating the surface to be rendered optically black(1) by applying at least four or five coats of an inorganic composition comprised primarily of an alkali metal silicate and pigment, and(2) by spraying at least the last two surface coatings, and having them comprise the above milled mixture, and(c) Drying at least the coats prior to the last two coats, before applying the last two coats.

Abstract: A hydraulic cement mix including hydraulic cement, aggregate, sufficient water to effect hydraulic setting of the cement, and an additive comprising glycerophosphoric acid or its salts, such as calcium, magnesium, potassium and sodium glycerophosphate, wherein the additive is present in an amount sufficient to increase the strength of the mix when hardened, generally in an amount of up to 0.2% by weight, preferably in an amount of between about 0.005% by weight and 0.2% by weight based upon the weight of the cement, with the range 0.01% to 0.1% by weight also being preferred.

Abstract: A hydraulic cement mix including a Portland type cement, aggregate, sufficient water to effect hydraulic setting of the cement, and an additive comprising an alkali or alkaline earth fluotitanate, wherein the additive is present in an amount sufficient to retard beneficially the setting and hardening of the mix. The additive is preferably selected from the group comprising calcium, potassium and sodium fluotitanate and is present in an amount of between about 0.005% by weight and 1.0% by weight based upon the weight of the cement.

Abstract: A hydraulic cement mix including hydraulic cement, aggregate, sufficient water to effect hydraulic setting of the cement, and an additive comprising at least one acetic acid ester of glycerin, wherein the additive is present in an amount sufficient to increase the strength of the mix when hardened. The additive is preferably selected from the group comprising monoacetin, diacetin, triacetin, and mixtures thereof and is present generally in an amount of up to 2.0% by weight based upon the weight of the cement, usually between 0.01% and 2.0% by weight.

Abstract: A hydraulic cement mix including hydraulic cement, such as Portland type or high alumina cement, aggregate, sufficient water to effect hydraulic setting of the cement, and an additive comprising the fruit of the carob tree, Ceratonia siliqua, wherein the additive is present in an amount sufficient to increase the compressive strength of the mix when hardened. The additive may take many forms, but is preferably selected from the group comprising raw or roasted, carob pods or beans, extracts of the pods or beans, or combinations thereof and is present in an amount of up to about 0.25% based upon the weight of the cement, preferably between about 0.1% by weight and 0.1% by weight based upon the weight of the cement, with between 0.01% by weight and 0.05% by weight based upon the weight of the cement being an additional preferred range.

Abstract: A process for removing boron contaminant from magnesium halide-containing brine wherein the brine is contacted with active magnesia to precipitate boron-containing magnesium hydrate and to remove at least 50%, and up to at least 95%, by weight of the total boron content of the untreated brine, without reduction of the magnesium halide content of said brine. The active magnesia is employed in an amount of from about 0.1% to about 10% by weight, preferably from about 2% to about 6% by weight, of the untreated brine, which may be heated e.g., from about 140.degree. F to the boiling point thereof, prior to contact with said active magnesia. Subsequently, the treated brine can be used, by reacting it with dolime, to form magnesium hydroxide which, in turn, can be calcined to produce MgO, each of which is a high-purity-low-boron product, i.e., less than 150 ppm boron on an oxide basis, and preferably less than 75 ppm. In addition, the MgO will contain less than 1.

Abstract: High strength Portland cement compositions comprised of Portland cement clinker which has been ground to a specific surface area of between about 4400 cm.sup.2 /g and up to 6000 cm.sup.2 /g, alkali or alkaline earth lignosulfonate in an amount of between about 0.75 and 1.25 percent by weight, sodium bicarbonate in an amount of between about 1.25 and 2.5 percent by weight, and gypsum in an amount of between about 1.5 and 4.0 percent by weight, wherein the lignosulfonate and the bicarbonate are present in a ratio of about one to two and the cement product formed has a porosity of less than about 5 percent by volume voids. The cement compositions have an adequate plastic period of from at least about 90 minutes, as well as adequate and/or improved one and twenty-eight day strengths of in excess of about 5000 psi and 6000 psi, respectively. Sand or sand, crushed rock and/or gravel can be incorporated into the cement mixes or compositions to form mortar and concrete products.