7results about How to "Increase negative charge" patented technology

A microbial self-healing cement-based material based on surface-modified basalt fiber and a preparation method thereof, which belongs to the field of building materials. The present invention aims to solve the problem that the existing basalt fiber and bacteria are used in microbial self-healing concrete, the basalt fiber is not conducive to the attachment and deposition of bacteria on the surface of the basalt fiber, and the performance still needs to be improved. The microbial self-healing cement-based material is composed of water, calcium lactate, a water reducer, cement, a microbial self-healing agent, surface-modified basalt fiber and standard sand. Methods: 1. Preparation of microbial self-healing agent; 2. Surface modification of basalt fiber; 3. Mixing and curing of mortar. The present invention is used for a microbial self-healing cement-based material based on surface-modified basalt fiber and its preparation.

The invention discloses a charge-modified polyether sulfone hollow fiber membrane with a variable-diameter pore structure and a preparation method thereof. The preparation method comprises the following steps: (1) mixing polyether sulfone resin, sulfonated polyether sulfone, a pore-forming agent, polyethylene glycol and an organic solvent to prepare a membrane casting solution; (2) extruding the membrane casting liquid and the core liquid from a single-layer spinneret plate from outside to inside, immersing the membrane casting liquid and the core liquid into a coagulating bath through an air gap to generate primary membrane filaments, introducing the primary membrane filaments into a rinsing bath for rinsing through a filament guide roller, winding and collecting the primary membrane filaments through a filament collecting roller, and then soaking the collected membrane filaments in pure water to obtain a sulfonated polyethersulfone modified hollow fiber membrane; and (3) soaking the sulfonated polyethersulfone modified hollow fiber membrane in a sulfomethyl water-soluble phenolic resin aqueous solution, and cleaning with pure water. The polyethersulfone hollow fiber membrane obtained by the invention comprises the compact layer and the microporous layer from inside to outside, and has the advantages of higher protein yield, excellent pure water flux and high filtering efficiency.

The application discloses a salt-resistant water-non-dispersible material for oil well cement and a preparation method thereof. The salt-resistant water-non-dispersible material for oil well cement comprises the following components in the form of weight parts: 100 parts of N,N-dimethyl acrylamide, 3-6 parts of acrylic acid, 10-20 parts of 2-acrylamide-2-methylpropanesulfonic acid, 5-15 parts of a cyclic monomer, 0.1-0.4 parts of a branching agent, 5-15 parts of a cationic monomer, 0.3-3 parts of a crosslinking agent and 400-500 parts of water. The salt-resistant water-non-dispersible material prepared by the application has good salt resistance, can significantly improve the anti-dispersion performance of the cement slurry when used in a salt water and sea water cement slurry system with a NaCl content of 18 wt% or less, and has excellent rheological performance.

The invention relates to the technical field of biological detection, in particular to a method for simultaneously detecting multiple membrane proteins on the surface of extracellular vesicles. On the basis of a biosensor, the invention provides an'electrical sandwich 'determination method, negative charges of the antibodies are increased by independently coupling the antibodies of the second to-be-detected membrane protein to the nth to-be-detected membrane protein with the single-chain DNA with negative charges, so that the electrical response of the antibodies when the antibodies are combined with the extracellular vesicle surface membrane protein is enhanced; the method can be used for detecting sEVs subtypes simultaneously containing various extracellular vesicle surface film proteins, and has important significance in the field of biological detection.

The invention relates to a method for preparing a nanofiltration membrane by using sodium p-styrenesulfonate as a water phase additive. Infiltrating the support membrane in a water phase solution containing sodium p-styrenesulfonate and piperazine so that the support membrane is fully infiltrated by the water phase solution; coating the surface of the membrane with the oil-phase solution, and carrying out interfacial polymerization reaction to form an aromatic polyamide separation layer; and placing the membrane in an oven at 70-90 DEG C for heat treatment to prepare the aromatic polyamide composite nanofiltration membrane. Sodium p-styrenesulfonate can reduce the interfacial tension of a water / oil phase in the interfacial polymerization process, promote diffusion and uniform distribution of piperazine, strengthen the interfacial polymerization reaction and improve the cross-linking degree of a separation layer. The aromatic polyamide composite nanofiltration membrane prepared by the method has the characteristics of high flux and high selectivity at the same time. The method has the advantages of being simple in preparation process, low in cost and easy to implement. In addition, reference can be provided for preparation of other high-performance interfacial polymerization nanofiltration membranes.

The invention belongs to the technical field of adsorbent preparation, and provides a kind of efficient adsorbent and preparation method thereof for uremia, the preparation method of the efficient adsorbent comprises the following steps: (1) modified chitosan is dispersed in deionized water, 1,2-dichloroethane is added, ultrasonic 20-40min, adsorbent material is added, stirring 10-15h, and reactant is obtained; (2) modified carboxymethyl cellulose, sodium hydroxide, deionized water are mixed, stirring 1-3h, reactant and epichlorohydrin obtained in step (1) are added, heated to 50-70℃, heat preservation reaction 2-4h, washing, drying, and efficient adsorbent is obtained. The efficient adsorbent of the present invention has fast adsorption rate and high adsorption capacity for uremic toxins, and has good biocompatibility and blood compatibility, and has good market prospects in the field of wearable artificial kidney.

The present invention relates to the technical field of high-efficiency phosphate fertilizers, and specifically discloses a high-efficiency phosphate fertilizer for inhibiting cadmium absorption and a preparation method thereof. The method comprises the following steps: S1: a click chemical reaction occurs between thiolated nano-hydroxyapatite and 1-vinyl imidazole under ultraviolet irradiation to obtain modified nano-hydroxyapatite; S2: the modified nano-hydroxyapatite is added to deionized water to obtain a mixed solution A; diammonium citrate, ferrous sulfate heptahydrate, manganese phosphate, and zinc phosphate are added to deionized water and uniformly mixed to obtain a mixed solution B; at a rotation speed of 500 to 600 rpm, the mixed solution A is added dropwise to the mixed solution B, the stirring is continued, the mixture is allowed to stand at room temperature, and the mixture is purified to obtain a composite material; S3: the composite material and the passivator are used as a high-efficiency phosphate fertilizer for inhibiting cadmium absorption; when used, the mixture is sequentially used in the soil.