20 results about "Acid stable" patented technology

The invention provides a method for accurately regulating and controlling pores of an MXene material by utilizing a phosphonic acid ligand, which mainly comprises the following key steps of: directionally removing a main group element (A) layer of an MAX precursor by wet etching to obtain lamellar MXene, and then introducing a protonated quaternary amine compound intercalator to strip the MXene. And finally, carrying out functional modification and conversion by adopting a phosphonic acid ligand, and stably introducing phosphonic acid groups between layers and on the surface of MXene through solvothermal reaction to realize accurate regulation and control of interlayer spacing. The prepared material can realize efficient adsorption of uranyl in an acidic environment, shows high selectivity, high adsorption capacity and good acid stability and regeneration capacity to uranyl, provides a stable and efficient selective adsorption solution for treating high-acidity uranium-containing nuclear wastewater, and has a remarkable industrial application prospect.

The application provides an emulsion thickener with acid recovery stability and a preparation method thereof, and relates to the technical field of thickener.The raw materials of the emulsion thickener include polymerized monomers, emulsifiers, initiators, crosslinking agents, water and structural additives; the polymerized monomers include first monomers and second monomers, the first monomers are alpha, beta-unsaturated acid monomers, the second monomers are alpha, beta-unsaturated ester monomers, and the structural additives are polypeptides including polar amino acid residues.The emulsion thickener with acid recovery stability can quickly recover to the viscosity in the alkaline condition and gradually increase when the system changes from the alkaline condition to the acidic condition, effectively improves the response rate of network reconstruction, and realizes the self-repairing function.The preparation method of the emulsion thickener with acid recovery stability is simple and easy to operate, has good stability, and can be implemented in industrialization.

An analytical process for detecting compounds in a sample suspected of containing a peroxide-based compound, a nitrate-based compound, a nitrotoluene-based compound, or a nitramine-based compound includes treating the sample with a superbase and then contacting the sample with a composition. The composition includes or consists of a Ni-porphyrin and an acid and optionally an acid stable solvent.

The invention provides an analytical process, which preferably is a one-step process, for detecting in a sample peroxide-based explosives, and / or nitrate-based explosives , the process comprising contacting a sample suspected of containing a peroxide-based compound, especially a peroxide-based explosive, or a nitrate salt, especially a nitrate-based explosive, with a composition comprising a Ni-porphyrin, an acid and preferably an acid-stable solvent.

The present invention relates to an improved catalyst on the basis of a shaped catalyst body for hydrogenating carbonyl groups in organic compounds under the effect of acids and water, characterized in that the shaped catalyst body contains copper in an amount of 17.5 to 34.5 wt. %, relative to the shaped catalyst body and the copper is present in the shaped catalyst body to at least 70% in the form of a copper spinel CuAl2O4. The invention also relates to the production of the catalyst an to the use of same in the hydrogenation of carbonyl groups in organic compounds in the presence of acids and / or water.

An elution buffer for eluting one or more predetermined analytes from one or more analyte-specific antibodies or fragments thereof or for eluting one or more predetermined antibodies or fragments from a target antigen, wherein the elution buffer has a pH of 1 to 5; and the elution buffer comprises a predetermined amount of an acid-stable mass spectrum ionization control protein. Use of an elution buffer in the detection and quantification of an analyte (e.g., by mass spectrometry) is also described.

An oligomeric di(monophosphate) acid stabilizer conforming to the structure of formula (II) wherein n is n > 3. And a method for producing the acid stabilizer and a polyurethane prepolymer containing the acid stabilizer.

The invention belongs to the technical field of damaged reverse osmosis membranes with deteriorated separation performance, and provides an acid-resistant repair method for a damaged reverse osmosis membrane based on an intercoordination stability mechanism. The method comprises the following steps: firstly, carrying out hydrogen bond interaction on a natural antioxidant and a polyamide layer of the reverse osmosis membrane to construct a primary repair network; then, the metal ions and the antioxidant form a continuous repairing layer on the membrane surface through coordination, the compactness and stability of the repairing layer are further enhanced, and therefore efficient recovery of the membrane performance is achieved. On the basis of the soft and hard acid-base theory, through the selective coordination effect of hard acid-hard base and soft acid-soft base, the acid stability of a repairing layer is remarkably improved while the damaged site of the reverse osmosis membrane is rapidly repaired, and the service life of the membrane is prolonged; the technology is simple and convenient to operate, can be directly integrated in the off-line cleaning process of the existing membrane system, does not need additional equipment or complex process modification, has the advantages of mild reaction conditions, short repair period and the like, and has good engineering popularization and application values.

The invention discloses a diglycol amide compound with a tripod structure as well as a synthesis method and application thereof, and relates to the field of amide compounds, and the chemical name of the diglycol amide compound is 2, 2 ', 2' '-(((((nitroso tris (methylene)) tris (benzene-2, 1-diyl)) tris (nitrogen diyl)) tris (2-oxoethane-2, 1-diyl)) tris (oxy)) tris (N, N-dioctyl acetamide). The compound is constructed by taking tris (2-aminobenzyl) amine as a core skeleton and grafting three N, N, N ', N'-tetraoctyl diglycol amide chelating units. The Trapan-DGA compound disclosed by the invention shows excellent performance in the field of nuclide separation: in a 5.0 M nitric acid medium, the distribution ratio to Th (IV) reaches 12.4, and the separation factor to Th (IV) / U (VI) reaches up to 34.4. The compound has excellent acid stability, the extraction performance is stable in the nitric acid concentration range of 1.0-5.0 M, and the extraction equilibrium time is only 5 minutes. Meanwhile, the compound has good solubility in non-polar diluent kerosene, and effective extraction can be realized without adding an alcohol modifier.

The present invention discloses an acid-resistant α-amylase mutant and a preparation method thereof, and is effective in inhibiting the growth of Bacillus velezinis ( Bacillus from Velez ) α-amylase from source is subjected to site-directed mutagenesis, and the mutation is at least one of S242E, N569E, and N605D. The α-amylase mutant provided by the present invention has good acid stability, and at pH 1.9-4.0, the ability of the α-amylase mutant catalyzing starch hydrolysis provided by the present invention is significantly improved, and the availability of α-amylase under wider pH conditions is increased, and the problem of limited application caused by the poor acid resistance of existing α-amylase is solved. The present invention has a remarkable effect on improving the raw material utilization and product quality in starch processing industry and reducing production costs, meets the demand for acid-resistant α-amylase in the fields of energy, food and feed, has important social and economic benefits, and has broad application prospects.

The present invention relates to genetic engineering technology, and discloses a chitosanase, its encoding gene, recombinant vector, recombinant strain, fermenting agent and enzyme preparation, as well as their applications. The pure enzyme activity of this chitosanase is high, and it has obvious acid stability. When stored overnight under the condition that the optimal pH is 5.0, the enzyme activity only decreases by 8%. When stored overnight in the pH range of 3.0 - 6.0, the remaining enzyme activity is above 60%. It has high acid resistance and a large acid-resistant range, and has great application potential in the industrial production of chito-oligosaccharide. The recombinant strain provided by the present invention can efficiently produce chitosanase through high-density fermentation, and has prospects for industrial application.

The present invention discloses an immobilization method and application for effectively improving the acid stability of zearalenone lactone hydrolase, belonging to the field of biotechnology. The present invention uses an injection gel method to encapsulate ZEN hydrolase in hydrogel beads based on potassium carrageenan, and the acid stability of the enzyme is improved by co-encapsulation with an alkaline buffer Mg(OH)2. The Mg(OH)2 buffer obtained by the present invention is insoluble under neutral conditions, but dissolves when hydrogen ions diffuse into the hydrogel beads, thereby ensuring a neutral internal pH value. The use of a hydrogel bead co-encapsulation system containing a Mg(OH)2 buffer improves the stability of ZEN hydrolase in an acidic environment, and is suitable for a food-grade delivery system of ZEN hydrolase for acid-sensitive enzymes, with potential for industrial application.

The present invention relates to an improved chromium-free Cu-Al catalyst for the hydrogenation of carbonyl groups in organic compounds, characterized in that the catalyst contains a proportion of zirconium in an amount of 0.5% to 30.0% by weight. The present invention additionally also relates to the preparation of the catalyst and to the use thereof in the hydrogenation of carbonyl groups in organic compounds.

The invention belongs to the field of molecular sieve preparation, and provides a method for realizing stable migration of Lewis acid into a molecular sieve framework under the assistance of B atoms and application of the Lewis acid, and the method comprises the following steps: adopting a post-treatment method, taking a B-containing molecular sieve as a silicon source, adding a zirconium source, a structure-directing agent and water, uniformly mixing, performing hydrothermal crystallization, centrifuging, washing, drying and calcining to obtain a Zr-G molecular sieve; the preparation method comprises the following steps: fully treating a Zr-G molecular sieve in an acid solution at 100 DEG C by adopting an acid treatment method, centrifuging, washing, drying and calcining to obtain the Zr-M molecular sieve. According to the invention, efficient introduction of Lewis acid in a molecular sieve framework is realized, the problems that weak acidic surface bonded species are mainly formed in post-synthesis construction of L acid sites, agglomeration and loss are easy to occur, confinement effect is lacked and the like are solved, and a new way is developed for comprehensive application of the Lewis acid molecular sieve in sustainable catalysis.

Improved acid stable and high temperature stable oleosome fractions from plant sources for edible applications as or in human consumed foods are described, such as in plant and nut milk and blends, juices and soda beverages, coffee blends, yoghurt products, ice creams, smoothies, and fruit juice popsicles.

The invention provides an imine bond covalent organic framework material as well as a preparation method and application thereof, and belongs to the technical field of new material preparation. The imine bond covalent organic framework material provided by the invention is a polymer as shown in a formula I, and four amino nitrogen groups of N, N, N ', N'-tetra (p-aminophenyl) p-phenylenediamine in the polymer are respectively connected with aldehyde carbon of terephthalaldehyde through C = N bonds. The imine bond covalent organic framework material provided by the invention is a porous crystalline framework material, gold can be adsorbed and recovered from a gold-containing solution through synergistic electrostatic adsorption and reduction effects of protonated tertiary amine and imine, and meanwhile, the material has an appropriate structure, can have excellent selective adsorption on gold, has excellent stability, and can be applied to the field of gold adsorption. The stability of the adsorption performance can be maintained under different pH value conditions, and particularly, the acid stability is remarkable.

The invention provides an emulsion thickener with acid return stability and a preparation method thereof, and relates to the technical field of thickeners. The emulsion thickener comprises the following raw materials: a polymeric monomer, an emulsifier, an initiator, a cross-linking agent, water and a structural additive, the polymeric monomer comprises a first monomer and a second monomer, the first monomer is an alpha, beta-unsaturated acid monomer, the second monomer is an alpha, beta-unsaturated ester monomer, and the structural additive is polypeptide comprising polar amino acid residues. When a system is changed from an alkaline condition to an acidic condition, the emulsion thickener with the acid return stability can quickly recover to the alkaline viscosity and gradually increase the viscosity, so that the response rate of network reconstruction is effectively improved, and a self-repairing function is realized. The preparation method of the emulsion thickening agent with the acid return stability is simple, convenient and easy to implement, good in stability and suitable for industrial implementation.

The present invention discloses a nanoparticle with acid stability, pH responsiveness and targeting Helicobacter pylori, as well as a preparation method and use. The nanoparticle has a core-shell structure; wherein the core structure is an amino-modified mesoporous iron oxide nanoparticle loaded with manganese porphyrin; and the shell structure is a polymer coating targeting Helicobacter pylori. The pH-sensitive nanoparticles prepared by the present invention have acid stability and good mucus permeability. The pH-sensitive nanoparticles can accurately target Helicobacter pylori in the stomach. Magnetic resonance imaging (MRI) based on the particles can provide real-time information on the biodistribution of the drug in the body, guide ultrasonic irradiation when the drug release is maximum, and activate the drug to produce 1 O2 can eliminate Helicobacter pylori, and its inhibitory effect on Helicobacter pylori in vivo is comparable to that of antibiotic-based triple therapy, but it has no obvious mammalian cell toxicity and interference with normal intestinal flora, and has better biosafety.

Provided are certain membranes useful in the filtration of liquids and removal of various contaminants therein. In certain aspects the membranes have as one component a polyamide such as Nylon 11 and / or Nylon 12. Also provided is methodology for manufacturing such membranes and their use in filtration and purification of liquids. Membranes of the disclosure thus prepared exhibit superior acid stability when compared to polyamide membranes prepared from Nylon 6 or Nylon 6,6.

The invention relates to a xylanase mutant with remarkably improved acid stability and a preparation method and application thereof, and belongs to the technical field of xylanase, the site of N75F of xylanase XynASP is mutated, and the amino acid sequence of the obtained mutant is shown as SEQ ID NO.1 or comprises an amino acid sequence which has at least 90% sequence homology with SEQ ID NO.1 and contains N75F mutation. The detection result shows that the optimal pH value of the mutant XynN75F is 3.0 and is reduced to a certain extent compared with that of a wild type, and the mutant XynN75F is closer to an acid environment. Besides, the acid tolerance of the XynN75F is excellent, the residual enzyme activity of the XynN75F under each pH gradient is superior to that of a wild type after heat preservation is carried out for 1 hour under the condition that the pH is 2.0-8.0 and the temperature is 50 DEG C, particularly, the acid tolerance of the XynN75F is more prominent in an acid interval, and it is further proved that the acid resistance of the mutant is remarkably improved.