81 results about "Calcium ion binding" patented technology

A bond is created between a gypsum matrix and titanium or zirconium based coupling coating applied onto a glass fiber during gypsum board cure. The commercially available titanium or zirconium based coupling has a generic formula of the type [RO-}-nTi—[—OXR′Y]4-n or [RO-}-nZr—[—OXR′Y]4-n. These coupling compositions chemically bond to glass fibers by replacing the —OH groups present on the glass fibers in aqueous solutions with Ti—O or Zr—O bonds. In order to bond with calcium ions in hydrated gypsum crystals, the X functionality is selected to be a phosphate or pyrophosphato group. The bond between the glass fiber and the titanium or zirconium based coupling composition is due to the formation of a monolayer, while the bond between the hydrated gypsum crystal and the coupling composition is intermittent due the acicular structure of gypsum crystals. The titanium or zirconium based coupling composition coating on glass fibers bonded to the gypsum matrix results in load transfer between the gypsum matrix and the glass fibers, resulting in improved flexure strength and nail pullout resistance. The Titanate/Zirconate can also be used as a board mechanical properties enhancing agent without addition of glass fiber.

A method for increasing the concentration of calcium carbonate in a geomaterial that contains indigenous microorganisms capable of hydrolyzing urea to ammonia, which method includes enriching the geomaterial with a source of nutrients, adding urea to the geomaterial which is hydrolyzed to ammonia and which raises the pH of the geomaterial, and adding a source of calcium ions to the geomaterial. Carbonate ions obtained by the hydrolysis of the urea combine with calcium ions to form calcium carbonate.

The invention discloses an organic composite reinforced concrete rust inhibitor and a preparation method thereof. According to the invention, the rust inhibitor is prepared from well-mixed materials of, by weight: 30-40% of alcohol amine carboxylate, 5-10% of sodium monofluorophosphate, 0.1-0.5% of an anionic surfactant, and balance of water. The rust inhibitor has a good diffusion performance inconcrete, and can simultaneously acts upon the cathodes and the anodes of steel bars. The trust inhibitor forms stable chelate rings with the steel bars, and has an excellent rust inhibiting performance. Also, the anions in the rust inhibitor can be combined with calcium ions in the concrete, such that precipitates are formed. With the precipitates, capillary pores in the concrete can be obstructed, and the chloride ion penetration resistance of the concrete can be improved.

The invention discloses a method for synergistically enhancing the strength of a recycled concrete aggregate by composite microorganisms. The method comprises: A, hydrolyzing urea through Bacillus pasteurii to obtain carbonate, hydrolyzing an organic phosphate monoester through bacillus subtilis to obtain phosphate ions and preparing a microorganism composite bacterial solution a from the two solutions, B, immersing a recycled concrete aggregate in the composite bacterial solution a, C, adding equimolar calcium ions into the solution for a reaction to obtain a calcium carbonate-hydroxyapatitecomposite gel material, and D, mixing the composite bacterial solution a, the equimolar calcium ions and cement mortar and mixing the mixture and the recycled concrete aggregate. After mixing of the composite bacterial solution a, the produced hydroxyapatite and calcium carbonate fill gaps of the recycled concrete aggregate. In the growth and reproduction of Bacillus pasteurii, urease is producedand fast hydrolyzes the urea into carbonate and ammonium ions and the ions are bonded to calcium ions so that calcium carbonate gel is produced. The bacillus subtilis produces alkaline phosphatase inthe growth and reproduction and the alkaline phosphatase hydrolyzes the organic phosphate monoester so that phosphate ions are obtained. The method can effectively strengthen the recycled concrete aggregate.

The invention discloses a method for co-producing calcium sulphate and magnesium hydrate by ammonia alkali waste liquid and concentrated seawater. The method comprises the technical steps of ammonia alkali waste liquid purification, calcium hydroxide dissolving, crystallization reaction, kettle bottom slurry liquid separation washing and overflowing slurry liquid filtering washing. The calcium sulphate is dissolved in the purified ammonia alkali waste liquid, formed mixed solution and the concentrated seawater are respectively and continuously added into a crystallization reactor, the circulation mixing is carried out under the effect of a circulation lifting device arranged in the crystallization reactor, sulfate ions and calcium ions are combined to form large-grain-diameter calcium sulfate crystals to be settled to the bottom of the crystallization reactor, magnesium ions and hydroxyl ions are combined to form magnesium hydrate with smaller grain diameter, and the magnesium hydrate is lifted in the crystallization reactor through the circulation lifting device and overflows from an overflowing opening. The method has the characteristics of simple work procedure, high separation efficiency and the like, and the comprehensive utilization of resources is further realized.

The embodiment of the invention provides a technology and production system for producing aluminum acid calcium powder by using aluminum ash. The technology comprises the steps that after being brokenand screened, the aluminum ash is evenly mixed with limestone in a predetermined proportion, and a mixed raw material is obtained; the mixed raw material is subjected to ball milling to obtain mixedraw material powder; the mixed raw material powder is subjected to preheating decomposition to obtain a decomposed mixed raw material; the decomposed mixed raw material is sintered to obtain sinteredblocks; the sintered blocks are cooled, ground and screened in sequence to obtain the aluminum acid calcium powder. The production system for producing the aluminum acid calcium powder by using the aluminum ash comprises a raw material preparation device, a raw material calcination device and a clinker processing device. Fluorides, nitrides and other harmful substances in the aluminum ash are bound with calcium ions by using the processing technology and the production system to be prepared into harmless substances, the aluminum ash can be processed into the harmless substances to protect theenvironment, moreover, the aluminum acid calcium powder produced by using the method is a main raw material for preparing an efficient water treatment agent, and the economic and environmental benefits are significant.

The invention relates to a water-soluble calcium nitrate production method, and especially relates to a method for producing water-soluble calcium nitrate dihydrate and phosphoric acid by decomposing phosphorite through nitric acid. The method comprises the following steps: decomposing phosphorite by nitric acid to prepare an acidolysis liquid, carrying out freezing crystallization of the acidolysis liquid to separate a calcium nitrate crystal and phosphoric acid, dissolving the calcium nitrate crystal, carrying out deep impurity removal of the obtained calcium nitrate solution, carrying out evaporative concentration of the calcium nitrate solution, removing water from the obtained crystal, and carrying out ammonium nitrate wrapping granulation to prepare calcium nitrate dihydrate having a water solubility of not less than 99.9%. The method avoids the insufficient utilization of sulfate radicals residual in phosphogypsum of sulfuric acid methods when wet phosphoric acid is simultaneously produced, and the production of the high-added-value calcium nitrate dihydrate through the combination of nitrate radicals with calcium ions has the advantages of widening of the product chains of phosphoric acid or nitric phosphate enterprises, economic utilization of the nitrogen element in nitric acid, and improvement of the competition advantages of the enterprises.

Methods for extending light-emitting time of a solution of a calcium-binding photoprotein that instantaneously emits light by binding to calcium ions are provided. In the light-emitting reaction system of a solution of a calcium-binding photoprotein, a light-emitting reaction is performed in the presence of an anion capable of binding to the calcium ion or the cation that can be substituted for the calcium ion and/or a cation that can bind to the calcium-binding site of the calcium-binding photoprotein with a lower affinity than the calcium ion or the cation that can be substituted for the calcium ion without activating the calcium-binding photoprotein.

The invention specifically relates to a shell nacre-like recombinant protein CSCa and a method for regulating and preparing calcium carbonate by using the same, belonging to the field of material preparation. The recombinant protein CSCa is composed of a chitin binding domain, a silk protein repetitive sequence and a calcium ion binding domain. The method for regulating and preparing calcium carbonate by using the same comprises the following steps: uniformly mixing chitin with a recombinant protein CSCa solution; adding a NaHCO3 solution when chitin and recombinant protein CSCa are fully combined together and carrying out uniform mixing under stirring; then adjusting a pH value to 8.5 to 9.5 and adding a CaCl2.2H2O solution; and carrying out a mineralization reaction under the condition of stirring so as to obtain mineralized calcium carbonate. Vaterite-phase calcium carbonate can be prepared by using the method provided by the invention and can be stably maintained for a period of time under the action of the recombinant protein CSCa, which is an unusual phenomenon in the process of mineralization and is of great promotion significance to deeper understanding of the mechanism of mineralization.

The invention relates to heavy metal ion filter paper and a preparation method thereof. The preparation method disclosed by the invention comprises the following steps: fully beating, splitting and brooming wood pulp cellulose in a beating machine; by taking calcium salt as a calcium source, taking ethyl orthosilicate as a silicon source, and taking the wood pulp cellulose as the support and reaction zone, hydrolyzing the ethyl orthosilicate to produce silicate under alkaline conditions, binding with calcium ions to produce calcium silicate to be loaded onto the fibers in situ; mixing softwoodpulp and hardwood pulp loaded with porous calcium silicate according to a certain ratio, adding a wet strength agent, homogenizing and making filter paper. The defect that a template agent generallyneeds to be added during synthesis of porous calcium silicate or synthesis is performed under ultrasonic conditions is overcome, and the produced calcium silicate can be highly dispersed and firmly bound onto the fibers, so that the stability of the cellulose-supported porous calcium silicate filter material is improved. The made filter paper has ability of adsorbing and intercepting heavy metal ions in wastewater, the heavy metals in the wastewater can be removed by virtue of common filtration, and the heavy metal ion filter paper has wide popularization and application value.

The invention discloses a modeling method of excitation and contraction processes of fast muscle fibers of skeletal muscle. The method includes the steps of (1) adopting half sarcomere as a unit and building an electrophysiologic mathematic model of fast muscle sarcolemma of the skeletal muscle; (2) adopting the half sarcomere as a unit and building a geometric model of calcium ions circulation; (3) building a mathematic model of a release process of calcium ions from a RyR channel on terminal pond; (4) building a mathematic model of combining calcium ions and magnesium ions with ATP and parvalbumin separately; (5) building a methematic model of cross-bridge power and a mathematic model of combination of the calcium ions and troponin; (6) building a sarcolemma fatigue model and a metabolism fatigue model during the excitation and contraction processes of the fast muscle fibers of the skeletal muscle. The modeling method of the excitation and contraction processes of the fast muscle fibers of the skeletal muscle is based on the biologic structure of the skeletal muscle, and can achieve building of mathematic models in each link, more precise analysis, simulation and prediction of the excitation and contraction processes of the sarcolemma of the skeletal muscle, and provide theoretical guidance for disease diagnoses and rehabilitation therapies of the skeletal muscle.

The invention discloses natural moringa organic calcium and a preparation method thereof. Moringa leaves are taken as main raw materials of the natural moringa organic calcium; and staged mixed-microorganism fermentation is adopted so as to degrade the moringa components during the fermentation process so as to extract natural water-soluble calcium from the moringa leaves, wherein the mixed microorganisms comprise lactic acid bacteria and yeast. Synergistic effects and fermentation characteristics of different microorganisms in fermentation are utilized so that high-molecular proteins and saccharides in the moringa leaves are further degraded so as to obtain polypeptides, amino acids, organic acids and so on; and carboxyl groups and amino groups on polypeptide molecule chains can combine with calcium ions so as to change chemical form of the moringa calcium, and thus, intestinal absorption rate of the moringa calcium is increased so as to improve bioavailability of the moringa calciumand increase bone density. A freeze-drying technology is adopted so as to preserve biological activities of the polypeptide, the amino acids and so on to the maximum extent; and the prepared freeze-dried moringa powder is uniformly mixed with auxiliary materials, including natural sweet orange powder, aspartame, xylitol, soybean lecithin and so on, so as to prepare the moringa organic calcium products.

The invention provides a mutant of cyclodextrin glycosyltransferase (CGT enzyme for short) with capability for high-yield of beta-cyclodextrin and mutating method thereof, and belongs to the fields of gene engineering and enzyme engineering. The invention employs a site-directed mutagenesis method for improving beta-cyclodextrin production capability of CGT enzyme, and provides a mutating scheme for improving beta-cyclodextrin production capability of Bacillus circulans STB01CGT, that is alanine at the 315th position of the calcium ion binding site in CGT enzyme is changed into arginine (Arg) or aspartic acid (Asp), and the mutants A315R and A315D are obtained. Compared with the wild CGT enzyme, the two mutants have higher beta-cyclodextrin production capability, and are suitable for industrial production of beta-cyclodextrin.

The invention relates to an improved technological method for preparing 2, 3, 4, 5-tetrachloride phthalic anhydride. The improved technological method includes bonding 3, 4, 5, 6-tetrafluorophthalic acid and calcium ions in water phases to generate 3, 4, 5, 6-calcium tetrafluorophthalic acid; filtering out solid, then removing single-molecule calcium carbonate in water environments under the catalytic effect of specific strong acid and strong alkali salts to generate 2, 3, 4, 5-tetrachloride phthalic anhydride; continuing to carry out reaction on the generated 2, 3, 4, 5-tetrachloride phthalicanhydride and calcium carbonate to generate corresponding salt and releasing carbon dioxide; regulating pH (potential of hydrogen) values of water phases after the reaction is completely carried out;cooling and filtering the generated 2, 3, 4, 5-tetrachloride phthalic anhydride to obtain final finished products. The 3, 4, 5, 6-tetrafluorophthalic acid is used as a starting material. The improvedtechnological method has the advantages that the improved technological method is high in decarboxylation reaction yield and suitable for industrialization production, organic solvents can be omitted, waste gas, wastewater and industrial residues are easy to treat, and the like.

The invention discloses building antifouling coating. The building antifouling coating mainly comprises polyacrylate, light calcium carbonate, titanium dioxide powder, infrared ceramic powder, hollowceramic micro-spheres, a nanometer-sized antifouling auxiliary, dispersing agents, antifreezing agents, thickening agents, wetting agents, defoaming agents, coalescing agents, film formation catalystsand water. Inorganic modified graphene oxide is used as the antifouling auxiliary. The building antifouling coating has the main advantages that metal ions are attached to the surfaces of the graphene oxide, are treated by polycarboxylic acid type efficient water reducers and then are no longer bonded with calcium ions generated after the light calcium carbonate in the building antifouling coating is dissolved, good dispersion effects can be realized, trace titanium dioxide P25 is attached to the surfaces of the graphene oxide, and accordingly excellent self-cleaning effects can be realized;the added trace film formation catalysts act with organosilicon compounds and the polyacrylate, and accordingly the film formation properties can be obviously improved; the building antifouling coating does not contain harmful organic solvents or other toxic and harmful substances and is an environment-friendly product.

The invention relates to the technical field of road surfaces, and provides an asphalt concrete road surface construction method to aim at the problem that a structure is prone to damage after long-time using. According to the technical scheme, the asphalt concrete road surface construction method includes the following steps that S1, a foundation pit is excavated; S2, the bottom of the foundationpit is compacted; S3, substrate filling is carried out; S4, the road surface is poured, specifically, asphalt concrete is poured on a substrate to form a road surface layer; and S5, the road surfacelayer is compacted. The asphalt concrete is prepared from the following components in percentage by mass: 100 parts of asphalt, 15 to 20 parts of silicate cement, 20 to 25 parts of water, 30 to 40 parts of sand, 40 to 50 parts of stone, 5 to 6 parts of acrylic emulsion, 2 to 3 parts of casein, and 0.5 to 1 part of fatty alcohol polyethenoxy ether. The casein is added into the asphalt concrete andused for combining with calcium ions in the silicate cement to form a cross-linking network between molecules, thus molecular movement is further obstructed, so that compression resistance strength ofthe asphalt concrete is improved, and structural stability of the asphalt concrete is improved.

The invention relates to a nanometer bone repairing material and a preparation method thereof, and belongs to the technical field of biomedical materials. Bovine bone powder is calcined at high temperature to produce biphasic calcium phosphate in a beta-tricalcium phosphate crystal form, and with the biphasic calcium phosphate as a framework, pearl protein and fish maw collagen are crosslinked andfilled into a porous structure of the biphasic calcium phosphate, so that the brittleness and mechanical properties of the nanometer bone repairing material are improved; in the process of guiding tissue regeneration, the degradation rate of the nanometer bone repairing material is adapted to tissue growth, so that the spatial capacity of a bone defect position is maintained to prevent a fibroustissue from entering a bone defect area, and a degraded product is prevented from quickly entering a body to affect the tissue regeneration at the bone defect position; in addition, the pearl proteinis used for regulating the deposition rate and the surface morphology of CaCO3, a calcium ion binding condition is adjusted, nucleation of calcium carbonate crystals is accelerated, the alkaline phosphatase activity is promoted, osteoblast differentiation is induced, formation of mineralized nodules is promoted, osteoclast differentiation and bone tissue absorption are inhibited, and bone repair is effectively promoted.

The invention relates to a cellulose-loaded porous calcium silicate filter material for heavy metal ion filtration and a preparation method thereof. The preparation method comprises fully beating, devillicating and brooming wood pulp fibers through a beater, hydrolyzing tetraethoxysilane through a calcium salt as a calcium source, tetraethoxysilane as a silicon source and the wood pulp fibers as support and reaction places under alkaline conditions to obtain silicate which is bonded to calcium ions to form calcium silicate loaded by the cellulose in situ. The preparation method solves the problem that the porous calcium silicate synthesis method needs a template agent or ultrasonic conditions, realizes high dispersion of the produced calcium silicate and firm bonding of the calcium silicate to fibers, and improves the stability of the cellulose-loaded porous calcium silicate filter material and the ability to adsorb heavy metal ions. The product can be used as a heavy metal wastewateradsorbing material and a filter column filling material, has good treatment effects and is suitable for treatment on wastewater containing various heavy metals. The preparation method has simple processes, is carried out under mild conditions and has a wide promotion range and a large use value.