505 results about "Double network" patented technology

A material that can be applied as implants designed to artificially replace or augment the cornea, such as an artificial cornea, corneal onlay, or corneal inlay (intrastromal lens) is provided. The artificial corneal implant has a double network hydrogel with a first network interpenetrated with a second network. The first network and the second network are based on biocompatible polymers. At least one of the network polymers is based on a hydrophilic polymer. The artificial cornea or implant has epithelialization promoting biomolecules that are covalently linked to the surface of the double network hydrogel using an azide-active-ester chemical linker. Corneal epithelial cells or cornea-derived cells are adhered to the biomolecules. The double network has a physiologic diffusion coefficient to allow passage of nutrients to the adhered cells.

The invention discloses a preparing method for infrared response high-strength hydrogel for cartilago articularis repair. The preparing method mainly includes the operation steps that polysaccharide or protein is modified in a double bond forming mode through methacrylic acid, methacrylic anhydride and methacrylate substances, so that the polysaccharide or the protein has a double-bond group in a side chain and is capable of being polymerized to form the hydrogel. Under the action of an initiator and a cross-linking agent, N-isopropyl acrylamide and the polysaccharide or the protein modified in the double bond forming mode form the double-network high-strength hydrogel through in-situ polymerization. The prepared infrared response high-strength hydrogel is high in biocompatibility and excellent in mechanical property and has good application prospects in the field of cartilago articularis repair.

The invention discloses a method for updating and using a secret key in a power grid SSL VPN. The method conducts double network combination on a quantum secret key distribution network and a power system dispatching data network, and aims to apply an unconditionally secure quantum secret key to a power grid in a double network combination mode, and the safety of power data transmission is guaranteed. The specific method that the two networks are combined is provided, three modes that the quantum secret key is applied to the power grid SSL VPN are achieved, and specific communication processes in the network after combination are achieved. The method for updating and using the secret key in the power grid SSL VPN has the advantages of being convenient and practical, saving in cost, and meanwhile capable of enhancing the safety of transmitting data.

The invention discloses a preparation method of hydrogel for cartilage repair and with tissue inductivity. The preparation method comprises the following main steps: A, polysaccharide or protein double bonding, B, hydrogel preparation, and C, adsorption of growth factors. According to the preparation method, double bonded natural polysaccharide/protein and methacrylamide dopamine which are completely degradable are used as the main components, and hydrogel adopting a double network structure can be formed through free radical polymerization of two materials of double bonded polysaccharide/protein and methacrylamide dopamine. Then hydrogel adsorbs biological activity growth factors through the dehydration and reswelling functions, and the growth factors are fixed into hydrogel throguh the dopamine component. The hydrogel obtained according to the preparation method is excellent in biological degradability and cell/tissue affinity, high in activity of the loaded growth factors and good in slow release performance, and can better induce cartilage regeneration and promote cartilage repair.

The invention provides switching methods for transmitting antennas and terminal equipment. A method comprises the steps of obtaining network architecture of wireless networks in which the terminal equipment is located when the terminal equipment is in a double-network connection state; determining a first priority of a first network for transmitting control plane data and a second priority of a second network for transmitting user plane data, according to the network architecture; and switching the transmitting antennas according to the first priority and the second priority, wherein the double-network connection state indicates that the terminal equipment is connected with the first network and the second network at the same time, and the first priority is higher than the second priority.According to the methods provided by the invention, when the transmitting antennas employed by the first network and the second network need to be switched, the transmitting antennas can be switchedaccording to the determined priorities, conflict of the first network and the second network in a transmitting antenna switching process can be effectively controlled, and communication quality is improved.

The invention discloses a method for preparing a high-strength double-network hydrogel stent by virtue of 3D printing. The method comprises the following steps of adding a polymer monomer N, N-dimethyl acrylamide, an initiator, a crosslinking agent and sodium alginate (SA) into deionized water to form a solution and adding inorganic powder hydroxyapatite to obtain a sol; controlling and extruding the sol by a robot dispenser, and carrying out 3D printing molding to obtain a sol stent; placing the sol stent under ultraviolet light so that the monomer in the stent is subjected to photopolymerization and chemical cross-linking reaction to form a layer of chemically cross-linked network pre-molded hydrogel stent; immersing the pre-molded hydrogel stent into a CaCl2 aqueous solution so that SA in the stent is subjected to physical crosslinking to form a second layer of physically cross-linked network so as to obtain the hydrogel stent having physically and chemically cross-linked double-network. The hydrogel stent prepared by the method has higher mechanical strength and fine internal structure, and the three-dimensional morphology of the stent can be conveniently regulated and controlled to adapt to the complex application requirements of tissue engineering materials.

The invention relates to chitosan double-network quick response-type injectable hydrogel and a preparation method thereof. The injectable hydrogel is prepared from chitosan or derivatives of the chitosan and sodium glycerophosphate serving as raw materials, and dialdehyde compounds or diepoxy compounds serving as crosslinking agents, wherein the mass ratio of the chitosan to the sodium glycerophosphate is 1:(0.5-10); the mass ratio of the crosslinking agents to the chitosan is (0.01-1):1. The method comprises the following steps: evenly mixing a hydrochloric acid aqueous solution of the chitosan with a sodium glycerophosphate solution in the environment at -1 to 5 DEG C, so as to obtain a solution of which the pH is 7-7.2, and evenly mixing the solution with a crosslinking solution at 35-37 DEG C. Transformation from a sol state to a gel state can be quickly finished under a specific condition, the process is irreversible, and the transition time is controllable. The chitosan double-network quick response-type injectable hydrogel has the advantages of simple reaction condition, short response time, good thermal stability of gel, high mechanical strength, good biocompatibility and the like. The chitosan double-network quick response-type injectable hydrogel is applied to the fields such as tissue filling and repairing, biological scaffolds, scar resistance and anti-adhesion, biogel, and quickly molding or three-dimensional printing materials and the like.

The invention provides chitosan-based double-network hydrogel. The hydrogel is of a double-network structure. A first network is chitosan graft hydrogel, and the chitosan graft hydrogel is formed by chitosan liquid, an initiator, a first single body and a cross-linking agent through grafting reaction. A second network is inserted inside the first network, and the second network is hydrogel which is formed by polymerization of a second single body, a cross-linking agent and a photo-initiator under the radiation of ultraviolet light and has high compression strength and tensile strength. Due to the introduction of chitosan, the biocompatibility of the hydrogel is improved. Thus, application of the double-network hydrogel in the fields such as biological medicine, the construction industry, the chemical industry and the mining industry is improved. The invention further provides a preparation method for preparing the chitosan-based double-network hydrogel. The method is simple in technology and enables industrialization to be easy.

The invention provides graphene oxide/chitosan grafted type double-network hydrogel. The graphene oxide/chitosan grafted type double-network hydrogel is of a double-network structure, wherein the first network is graphene oxide/chitosan grafted hydrogel which is formed by a graphene oxide solution, a chitosan solution, an initiator, a first monomer and a cross-linking agent through grafting reaction, the second network is inserted in the first network in a penetrating mode, and the second network is hydrogel which is formed by a second monomer, a cross-linking agent and a photo-initiator through polymerization under ultraviolet irradiation. The graphene oxide/chitosan grafted type double-network hydrogel has high compression strength and tensile strength. Due to the fact that the chitosan is introduced, biocompatibility of the hydrogel is improved, and then the double-network hydrogel can be better applied to the fields of biological medicine, construction industry, chemical industry, mining industry and the like. The invention further provides a preparation method for preparing the graphene oxide/chitosan grafted type double-network hydrogel. The method is simple in process, and industrialization can be easily achieved.

The invention provides a a design strategy of a novel adhesive hydrogel material and obtains a high-extension, self-healing, and high-adhesion biocompatible hydrogel material. Based on a double network structure design principle, polymerizable polyethylene glycol-based high polymer constitutes a first covalent crosslinked network, and hydrophilic high polymer with ultra-high molecular weight forms a second noncovalent crosslinked network through entanglement. A mesh size of a first network is larger than a molecular effective size of second network high polymer, and molecular weigh of high polymer forming a second network should be larger than a critical entanglement molecular weight thereof, so that effective molecular entanglement is formed, high-extension, self-healing, and high-adhesion characteristics are given to double network hydrogel. The novel hydrogel can rapidly and repeatedly form stable adhesion with surfaces of various materials. Damaged by an external force, the hydrogel can rapidly and repeatedly perform self healing. The material can be used as a cell cultivating carrier, a sewing-free novel dressing, and can be applied to wearble sensors.

The invention belongs to the field of biomedical materials and particularly relates to a preparation method of a co-crosslinked double-network hydrogel support for promoting cartilage repair and growth. The method comprises the following steps of (1) preparation of GelMA; (2) preparation of a photo-crosslinked polypeptide; and (3) preparation of a hydrogel support, namely preparing the hydrogel support from the GelMA and the photo-crosslinked HSNGLPL under the action of a photoinitiator. The prepared hydrogel support has an obvious effect of promoting new cartilage generation and cartilage defect healing, and is capable of regulating cartilage matrix secretion of normal chondrocytes around the injured tissue, mesenchymal stem cell migration to the injured part and cartilage differentiation; by virtue of a porous structure of the hydrogel support, the HSNGLPL can be crosslinked to the surface of a porous support, endogenous TFG-beta is effectively adsorbed, the concentration of local TFG-beta beta1 is improved and the effects of the biological support in the orthopedics fields, such as a cartilage defect and a cartilage injury are achieved.

The present invention provides an artificial corneal implant having an optically clear central core and a porous, hydrophilic, biocompatible skirt peripheral to the central core. In one embodiment, the central core is made of an interpenetrating double network hydrogel and the skirt is made of poly(2-hydroxyethyl acrylate) (PHEA). In another embodiment, both the central core and the skirt are made of interpenetrating double network hydrogels. The artificial corneal implant may also have an interdiffusion zone in which the skirt component is interpenetrated with the core component, or vice versa. In a preferred embodiment, biomolecules are linked to the skirt, central core or both. These biomolecules may be any type of biomolecule, but are preferably biomolecules that support epithelial and/or fibroblast cell survival and growth. Preferably, the biomolecules are linked in a spatially selective manner. The present invention also provides a method of making an artificial corneal implant using photolithography.

The invention discloses dynamic crosslinking double-network water gel as well as a preparation method and application thereof. The dynamic crosslinking double-network water gel is formed by a main network and a sub network through the penetration insertion winding and tying in a aqueous medium; the main network is dynamic covalent bond crosslinked polymers; the sub network is ion bond crosslinkedpolymers; the covalent bond crosslinked polymers are formed by polymers A and polymers B through covalent bond crosslinking; the ion bond crosslinked polymers are formed by polymers C and ion compounds through ion bonds. The preparation method is simple; the in-situ injection shaping can be realized; the fast in-situ formation of the water gel after the compounding of several kinds of ingredientsof the composite gel can be performed; the operation can be performed at the normal temperature. The water gel prepared by the method can fast form the required shape in required positions; the modelpreparation in advance is not needed; the speed is high; convenience is realized; meanwhile, the excellent mechanical performance of the water gel is considered, so that wide application prospects arerealized in the tissue restoration.

The invention relates to a rapid switching method and device for redundant double network cards, and belongs to the technical field of networks. The method comprises the following steps that: networkterminal equipment inquires the physical state of double network cards after initializing the redundant double network cards, activates a first network card with high priority, and simultaneously, thenetwork terminal equipment and a switch respectively start a GRRP protocol; judging whether to use attribute information interaction of a GRRP protocol between the network terminal equipment and theswitch to detect a communication link state or not according to a query result of the physical state of the double network cards, and judging whether the activated first network card works normally ornot according to a detection result; if it is judged that the activated first network card works abnormally, switching to a second network card, and updating the binding relationship between the MACaddress and the IP address; otherwise, not switching the network cards, and continuously inquiring the physical states of the double network cards. According to the invention, the defects of redundantdouble network card switching in aspects of fault detection completeness, real-time performance, accuracy and universality in the prior art are overcome.

The invention relates to a preparation method of alginate-graphene compound double-network gel beads. The preparation method comprises the following steps: (1) adding graphene oxide into an aqueous solution and carrying out ultrasonic treatment to prepare a uniform graphene oxide aqueous solution; (2) adding alginate into the graphene oxide aqueous solution and mechanically stirring to prepare a uniform mixed solution; (3) preparing a bivalent salt ion solution with a certain concentration and dropwise adding a peristaltic pump mixed solution into the bivalent salt ion solution at 0-100 DEG C to prepare alginate single-network gel beads loaded with the graphene oxide; (4) adding the single-network gel beads into an aqueous solution containing a reducing agent and carrying out water bath heat treatment to prepare the alginate-graphene compound double-network gel beads. Compared with the prior art, the preparation method is simple in process and liable to popularize; the prepared alginate-graphene compound double-network gel beads are excellent in resistance to salt and alkali, large in specific surface area and high in adsorbability.

The invention discloses double-network ionic gel with stimulation responsiveness and self repairability. Ionic liquid serves as a substrate, P(VDF-co-HFP) is used as a physical cross-linking network,dynamic covalent bond cross-linked PMA (polymethacrylate) copolymer serves as a chemical cross-linking network, and the two polymer cross-linking networks penetrate mutually to form a double network.Under synergistic effects of the double network, the ionic gel is excellent in mechanical performance, thermal stability and ionic conductivity. In addition, due to containing of reversible dynamic covalent bonds, self repairability under stimulation of light, thermal and the like can be realized. The ionic gel can be widely applied to lithium ion battery solid-state polyelectrolyte materials, gasseparation membranes, flexible electric devices, electrochemical sensors and the like.

Structural system and method are disclosed for building a simpler and more efficient double layer reticulated frame structure. The double layer reticulated frame structure includes an internal network that has a lower strut frequency than the external network. The lower strut frequency helps reduce the overall weight, cost, and construction time of the structure. Diagonal struts space apart and connect the internal and external networks. The diagonal struts are connected in an alternating manner such that no more than two diagonal struts are connected together at any point.

The invention discloses a novel high-strength hydrogel which is prepared by the following steps: synthesizing a first network hydrogel from a polyelectrolyte (such as hyaluronate, polyglutamic acid, chondroitin sulfate or polylysine); and after soaking the hydrogel in a double-bond functional polyethyleneglycol water solution for some time, taking out, and crosslinking to obtain the high-strength double-network hydrogel. The synthesized high-strength hydrogel has favorable biocompatibility, can be used as a tissue engineering/repair scaffold material or the like, and has wide applicability in the field of biomedical materials.

A method of forming a hybrid physically and chemically cross-linked double-network hydrogel with highly recoverable and mechanical properties in a single-pot synthesis is provided. The method comprises the steps of combining the hydrogel precursor reactants into a single pot. The hydrogel precursor reactants include water; a polysaccharide; a methacrylate monomer; an ultraviolet initiator; and a chemical crosslinker. Next the hydrogel precursor reactants are heated to a temperature higher than the melting point of the polysaccharide and this temperature is retained until the polysaccharide is in a sol state. Then the single-pot is cooled to a temperature lower than the gelation point of the polysaccharide and this temperature is retained to form a first network. Thereafter, photo-initiated polymerization of the methacrylate monomer occurs via the ultraviolet initiator to form the second network.

The invention relates to a remote video monitoring system and a remote video monitoring method based on public switched telephone network-Internet protocol (PSTN-IP) double-network cooperation. The system comprises a plurality of multimedia telephone terminals and one or more network video camera devices communicating with at least one of the terminals, wherein the terminals are in audio/non-audio communication with one another respectively through the PSTN/IP network; the non-audio communication is triggered by PSTN telephone dialing; telephone numbers are used as positioning identifiers of the terminals; IP addressing among the terminals is finished by using a mapping relation between a telephone number maintained in an IP network server and an IP address, so that the non-audio communication connection based on the IP network is established; and a calling terminal sends a control instruction to the network video camera device connected to a called terminal through the non-audio communication connection and acquires video data acquired by the network camera device. By the system and the method, the requirement of family remote video monitoring can be met better; furthermore, the system and the method have flexibility and security, are convenient to operate and are convenient for realizing server network management.

The invention provides a polymer composite material with a double-network structure and a preparation method thereof. The composite material contains fillers A and fillers B, wherein the size of the fillers A is 30 to 500 microns and the size of the fillers B is 1.0 to 20 microns; the size ratio of the fillers A to the fillers B is at least 20; the fillers A and the fillers B are uniformly distributed in a polymer base material, are in mutual overlap joint and penetrate through to form a conductive and heat-conducting access with a staggered network structure; the fillers B with the smaller size are distributed in grids of a loose network structure formed by the fillers A with the large size and are in mutual overlap joint to form a relatively dense network, and the inner part of the obtained composite material has a double-network structure which is good for moving electrons and reducing interface heat resistance, so that the conductive and heat-conducting performances are greatly improved at the same time. A method for constructing double networks by using the size difference of the two types of fillers has an ingenious concept and an operation method is simple; existing high molecular material modified machining equipment is used for realizing production; the method has low cost and is easy to popularize and apply.

The invention discloses a rail transit wireless communication system based on TD-LTE. The rail transit wireless communication system adopts flat network architecture based on IP and comprises two groups of network transmission subsystems A and B for providing communication channels for service terminals of an application layer, wherein the two groups of network transmission subsystems A and B work in a double-network simultaneous redundant bearing mode; each network transmission subsystem comprises a TD-LTE core network module EPC and a network management system located on a core layer, a distributed base station eNB located on an access layer, and a vehicular access terminal TAU located on a terminal layer. The system has perfect TD-LTE network interconnection and intercommunication interface and function, has access bearing capability of a plurality of services, and can provide reliable and redundant transparent transmission channels that can be flexibly reconfigured for service application systems.