79results about How to "Prevent structural collapse" patented technology

The invention provides devices that can be used to deliver a therapeutic agent to a treatment site within the vessel of a patient at increased pressure, while limiting the contact with and pressure placed on the vessel walls. Devices according to the invention include an expandable structure arranged around and on a tube having a lumen. The expandable structure may include a sealing ring that makes contact with the interior surface of a vessel to prevent or decrease fluid flow during delivery of a therapeutic agent. This allows delivery of a therapeutic agent with decreased risk of injury to the treatment site. The invention also provides for large lumen diameters, preventing shearing stress on therapeutic agents such as cell slurries.

The invention discloses a new method for on-site synthesis of a lithium ion conductive protection film for preventing poly-sulfide-ions diffusion on a surface of a lithium sulfur battery positive electrode, and an application therefor. The method is carried out by the steps of reducing the initial discharge voltage lower limit of a lithium sulfur battery taking a carbon sulfur composite as the positive electrode material to be lower than the normal working voltage 1.5V to generate the lithium ion conductive protection film; the film is quite high in the lithium ion conductivity and capable of preventing the poly-sulfide-ions from being dissolved in an electrolyte to enable the lithium sulfur battery to realize and maintain higher cycle performance, rate capability, coulombic efficiency and lower self discharge performance, so that the service life of the lithium sulfur battery is prolonged, and the use cost of the lithium sulfur battery is reduced; meanwhile, porous carbon with hierarchical pores used as the supporting material can accommodate the poly-sulfide-ions and lithium sulfide generated in charging and discharging processes of sulphur and the lithium sulfur battery; and the sulphur content in the carbon-sulfur composite material made from the porous carbon with the hierarchical pores is high, so that the comprehensive specific capacity of the carbon-sulfur composite product can be improved so as to further increase the overall energy density of the battery.

The invention belongs to the technical field of catalyst preparation, and particularly relates to a mesoporous and microporous MFI type nano molecular sieve with flaky pastry-shaped morphology and a preparation method and application thereof. The specific synthesis method is as follows: silicon source, aluminium source, mesoporous template, microporous template and water are mixed according to a proportion, the mixture is put into a reaction kettle and crystallized, the crystallized product is washed, dried and roasted and undergoes ion exchange, and thereby the mesoporous and microporous MFItype nano molecular sieve is obtained. The invention adopts Bola type tetra-head-group quaternary ammonium surfactant as the mesoporous template and tetrapropylammonium hydroxide as the microporous template, the guiding microporous structure can be assumed as a column, preventing the structural collapse of the roasted molecular sieve, consequently, the structural stability of the molecular sieve is remarkably enhanced, and the degree of crystallinity is high; the introduction of mesopores shortens the delivery path of micropores within unit volume, and decreases the mass transfer resistance ofmacromolecular catalytic reaction; and moreover, when applied in alkylation reaction (such as the heterogeneous reaction between sym-trimethylbenzene and phenylcarbinol), the mesoporous and microporous MFI type nanoscale molecular sieve has a good catalytic effect.

The invention provides a metal vanadate compound co-doped high-nickel ternary precursor and a preparation method thereof. A metal vanadate compound is doped in the coprecipitation reaction process, sothat one or two or more metals are synergistically doped to modify a nickel, cobalt and manganese or aluminum ternary precursor material; in the preparation process, a complexing agent solution and ametal solution are equally divided into an upper liquid inlet pipe and a lower liquid inlet pipe, and added into a reaction kettle; different regulation and control modes and growth process parameters are adopted in different stages of precursor growth; the ternary precursor with special primary particle morphology such as a flower sheet shape, a slender spindle shape, a thick and short rod shapeand the like or loose, porous, dense, hollow and other section morphology inside can be prepared, and the requirements of lithium batteries with different properties on precursors with different physical properties can be met.

The invention relates to a composite cathode material, comprising a base cathode material and a magnesium aluminate material MgAl2O4 coating the surface of the base cathode material. Preferably, the base cathode material is a nickel-cobalt-manganese ternary cathode material LiNixCoyMnzO2 or a nickel-cobalt-aluminum ternary cathode material LiNixCoyAlzO2, wherein x+y+z=1, 0 (x, y, z (1. The invention also relates to a preparation method of the composite cathode material and a lithium ion battery. The MgAl2O4 on the surface of the cathode material can protect the cathode material in the inner layer, improve the thermal stability of the cathode material, and thus improve the cycle stability and safety of the battery.

Method and apparatus for preventing collapse of a structure due to an earthquake by using a construction with a water chamber whose outside contacts a receiving area, provided to the earth's surface, and balance cables each connected to a plurality of weights and variable weights lighter than a predetermined weight. The water chamber is separated from the receiving area and raised form the earth's surface by draining off the water in the water chamber during an earthquake, and returns to its original position by increasing the weight of the water chamber once the earthquake completely stops.

The invention provides a preparation method of a ternary precursor, and belongs to the technical field of lithium ion battery materials. A technology combining intermittent concentration with a separation kettle is adopted to stably control the reaction condition of each step. The growth of secondary particles of a precursor is controlled by gradually reducing the pH in the reaction process, and the structure of the precursor is gradually changed from loose to dense by setting a precise clearing amount. The solid content of a slurry in a kettle is adjusted through the separation kettle to makethe precursor have a multilayer core-shell design with a loose-compact structure. The precursor prepared in the invention has the advantages of narrow particle size distribution, good sphericity degree and uniform size, has the multilayer core-shell with the loose-compact structure, and has enough space during circulation and crystal form mutation to avoid structural collapse and ensure the circularity, stability and safety of the precursor. Compared with precursors with internal complete voids, the ternary precursor of the invention has the advantages of compact and stable structure, high energy density, and solving of the problems of poor circularity, stability and safety of common ternary precursors.

The invention discloses a steel structure fire protection design method based on fire heat release rate measurement. The method includes the steps of 1, determining design parameters; 2, measuring heat release rate; 3, calculating the temperature of the outer surface, which plumes rise to, of a fire protective layer of a steel structural member, to be specific, 301, correcting the heat release rate, 302, calculating the temperature of a fire source place, and 303, calculating the temperature of the outer surface of the fire protective layer of the steel structural member; 4, calculating a test section-material comprehensive coefficient; 5, calculating an actual section-material comprehensive coefficient, to be specific, calculating the actual section-material comprehensive coefficient Alpha't according to a similarity relation; and 6, determining a minimum design thickness of the fire protective layer of the steel structural member. The method has the advantages that the steps are simple, the design is reasonable, implementing is convenient, effect is good, and well solved are such problems of the existing methods of calculating thickness of the protective layer of the steel structure that the process includes many steps, calculating time is long, iteration errors are unavoidable, and the influence of an actual fire upon the fire tolerance of the steel structure is not truly reflected.

The invention discloses a production method of an alumina carrier. The method comprises the following processes: (1) conducting excess volume impregnation of pseudo-boehmite by aqueous solution of ammonium salt; (2) filtering and drying the pseudo-boehmite impregnated with aqueous solution of ammonium salt in the step (1); and (3) using the pseudo-boehmite obtained in the step (2) as a raw material and forming, drying and roasting the raw material to obtain the alumina carrier. The alumina carrier produced by the method has the advantages of concentrated pore distribution, high specific surface area and high mechanical strength.

The invention relates to microporous carbon aerogel and a preparation method thereof. The microporous carbon aerogel is prepared by adding mixed eutectic molten salt composed of LiNO3, KNO3 and K2SO4 in a step of preparing organic wet gel; parameters include that specific surface area is 850-1350m2/g, pore size distribution is 1-2nm, pore volume is 0.38-0.43cm3/g, and adsorption amount of CO2 at normal temperature and normal pressure is 3.2-3.8mmol/g. The microporous carbon aerogel prepared by the method is high in specific surface area, narrow in pore size distribution range, large in pore volume and high in ability of adsorbing carbon dioxide. The preparation method is simple in steps, convenient to operate, low in production cost, short in process time and environment-friendly.

The invention provides a positive electrode material preparation method, which comprises the steps of A, performing mixing treatment and sintering treatment on a first lithium source and a doped cobalt source to obtain a material A; B, performing mixing treatment and sintering treatment on a second lithium source, a nickel-manganese-cobalt ternary precursor and nickel oxide to obtain a material B;C, performing mixing treatment and sintering treatment on the material A, the material B and a coating agent, wherein doping elements for doping the cobalt source comprise at least one of Mg, Al, Tiand Zr and Sb, and the coating agent comprises at least one of aluminum oxide, lanthanum oxide and yttrium oxide and nickel oxide. The positive electrode material prepared according to the positive electrode material preparation method has the advantages of high specific capacity, good cycle performance, small high-temperature storage thickness expansion rate, high energy density and the like, andcan meet the requirements of the market on the positive electrode material for the high-capacity high-performance lithium ion battery.

The invention belongs to the technical field of denitration, and discloses a composite denitration agent which is mainly prepared from talcum powder, phyllosilicate, ferric oxide, lanthanum oxide, barium oxide, urea, an oxidizing agent, an organic binder, an inorganic binder, carboxymethyl cellulose, a surfactant, a dispersing agent, polyhydric alcohol and other raw materials. The talcum powder and the phyllosilicate are used as carriers of the denitration agent, so that the thermal stability of the denitration agent is higher than that of a denitration agent with TiO2 as a carrier at a high temperature; the potassium oxide is loaded on the carrier, so that the denitration efficiency of the denitration agent can be effectively improved; the ferric oxide, lanthanum oxide, barium oxide and urea are used as denitration active components, so that the compounding effect of the denitration active components is efficiently achieved, and a complex with stable performance is favorably formed; in addition, the organic binder and the inorganic binder are added at the same time, so that the active centers of the active components can be highly dispersed, structural collapse caused by calcination of the denitration agent is prevented, and the high activity and high thermal stability of the denitration agent are further guaranteed. The invention also provides a preparation method of the denitration agent.

The invention relates to a preparation method of three-dimensional MoS2@C composite porous fiber for a lithium ion capacitor negative electrode material. The method comprises the following steps of (1) preparation of a reaction liquid, wherein through stirring, ultrasonic treatment and other modes, a three-dimensional porous carbon nanofiber matrix material is uniformly dispersed in distilled water, and a certain amount of ammonium molybdate and thiourea are added in proportion to prepare the reaction liquid; (2) hydro-thermal synthesis of the three-dimensional MoS2@C composite porous fiber, wherein the reaction liquid is transferred into a hydrothermal reaction kettle, the ammonium molybdate and the thiourea react to generate MoS2 with a flaky nano-flower ball structure, the MoS2 is uniformly filled and grows on a three-dimensional porous carbon nanofiber framework, and after repeated washing, absolute ethyl alcohol washing, suction filtration and vacuum drying are carried out, the three-dimensional MoS2@C composite porous fiber is obtained. The preparation method of the three-dimensional MoS2@C composite porous fiber for the lithium ion capacitor negative electrode material has the advantages that the three-dimensional porous carbon nanofiber framework effectively improves the electrical conductivity of the MoS2, the structural collapse caused by volume expansion in the cyclic process of the MoS2 is avoided, the preparation method is simple and convenient in operation, the controllability and repeatability are good, and the scale production is easy.

The invention discloses a preparation method and application of a self-supporting electrode, and particularly relates to a preparation method of a self-supporting electrode H-M(OH)2CO3/SM, wherein the preparation method is characterized in that rod-shaped transition metal basic carbonate M(OH)2CO3/SM is grown in situ on the surface of a supporting material SM for short, and then ligand organic small molecules of a conductive metal organic framework MOF, including but not limited to HHTP, HOB and HAB, are used for modifying the surface of a loaded M(OH)2CO3 rod-shaped material. Transition metal basic carbonate is modified in situ by using a conductive MOF ligand, so that the charge transfer capacity of the transition metal basic carbonate is improved, the conductivity and catalytic activity of M(OH)2CO3 in the electro-catalysis process are improved, and the comprehensive performance of a corresponding new energy device is improved.

The invention discloses a CC-NiO-CuCoS composite material. The CC-NiO-CuCoS composite material is composed of CC, NiO and CuCo2S4, wherein CC is a base material, the microstructure of CC is of a fibrous structure, and CC is used for providing a substrate, so NiO nanosheets cannot be stacked, and the conductive substrate is beneficial to ultra-high-speed transportation of electrons; the microstructure of NiO is a nanosheet structure, and NiO is loaded on the surface of CC and is used for providing extra pseudocapacitance; and the microstructure of CuCo2S4 is a nano-particle structure, and CuCo2S4 is attached to the surfaces of the CC and NiO nanosheets, and is used for stabilizing the sheet structure of NiO and covering a part of exposed CC. According to the invention, the CC-NiO-CuCoS composite material is prepared from CC, nickel nitrate hexahydrate, ammonium fluoride, urea, cupric acetate monohydrate, cobalt acetate tetrahydrate and thiourea are used as initial raw materials throughtwo-step hydrothermal preparation. The preparation method comprises the following steps of (1) cleaning and activation of CC; (2) preparation of a CC-NiO composite material; and (3) preparation of theCC-NiO-CuCo2S4 composite material. When the composite material is used as a supercapacitor electrode material, specific capacitance is 840 F g<-1>, and cycling stability after 3000 cycles is 100%.

The invention relates to a preparation method of a three-dimensional hollow ultralight structure carbon material and magnetic carbon composite material, which relates to a preparation method of a carbon material and magnetic carbon composite material, and is used for solving the technical problem that a material structure is likely to collapse after a template is removed when a porous material is prepared by taking polyurethane as the template. The preparation method comprises the following steps of: 1, preparing a polyacrylic acid grafted polyurethane sponge; and 2, immersing and soaking the polyacrylic acid grafted polyurethane sponge in an electrolyte solution, and then sintering the polyacrylic acid grafted polyurethane sponge taken out of the solution to obtain the three-dimensional hollow ultralight structure carbon material and magnetic carbon composite material. According to the preparation method provided by the invention, the problem that the material structure is likely to collapse after the template is removed when the porous material is prepared by taking the polyurethane as the template is avoided. The three-dimensional hollow ultralight structure carbon material and magnetic carbon composite material prepared by the preparation method is low in apparent density, and the minimum density of the material can reach 3.2mg/cm<3>. Raw materials adopted in the preparation method are low in cost and toxicity and easily available, and the preparation method is simple and easy to operate. The three-dimensional hollow ultralight structure carbon material and magnetic carbon composite material prepared by the preparation method has a multi-scale structure of nanometer, micrometer, millimeter and above. The preparation method belongs to the field of preparation methods of carbon material and magnetic carbon composite materials.

The invention discloses a photonic crystal infrared stealth material and a preparation method thereof, and belongs to the technical field of stealth materials. The photonic crystal infrared stealth material is prepared through the steps of substrate hydrophilic treatment, colloidal microsphere dispersion liquid preparation, colloidal self-assembly process, heat treatment process and the like. According to the photonic crystal infrared stealth material and the preparation method thereof, the infrared stealth performance of the material is slightly influenced by the angle of incident light, the stealth effect of infrared detection wavebands (3-5 microns and 8-12 microns) and the radiation heat dissipation performance of other wavebands can be achieved by adjusting the substance types and sizes of assembly elements, and meanwhile radar stealth of the waveband of 2-18 GHz is compatible.

The invention provides a buffering energy absorption structure capable of being stably deformed based on a shape memory alloy, relates to the technical field of energy absorption, and aims to solve the technical problems that in the deformation process of an existing energy absorption structure, a local deformation zone and structural collapse are likely to occur, thorough uniform steady-state deformation cannot be achieved, and consequently damage resistance is low, and deformation is uncontrollable. The buffering energy absorption structure capable of being stably deformed based on the shape memory alloy comprises a plurality of unit cell parts, wherein each unit cell part is provided with at least one hole; the plurality of unit cell parts are mutually connected to form a porous structure; and the unit cell parts are made of nickel-titanium memory alloy or iron-based memory alloy. The energy absorption structure can achieve uniform steady-state deformation after being loaded, formation of a local deformation zone is restrained, structural collapse is avoided, and damage resistance, robustness and controllability of the energy absorption structure are improved.

The invention relates to a composite lithium vanadium phosphate positive material, and a preparation method and applications thereof. The composite lithium vanadium phosphate positive material can beprepared by adopting two kinds of different carbon sources through two steps of in-situ coating; ion doping can be performed on a lithium vanadium phosphate positive material by doping an oxygen-containing compound; and through the utilization of a synergistic effect formed between a coating layer and an adulterant, the electrochemical performance of a lithium vanadium phosphate material can be further improved. The obtained composite lithium vanadium phosphate positive material has a mesoporous structure; the discharge specific capacity of the composite positive material is greater than 150 mAh/g at 5C multiplying power; capacity retention rate is greater than 91% after 1,000 cycles; and therefore, the composite lithium vanadium phosphate positive material has excellent specific capacity,rate performance and cyclic stability, and is suitable for large-scale popularization and application.

The invention discloses a lithium ion battery composite positive electrode material. The surface of the composite positive electrode material is coated with cerium and zirconium doped mesoporous aluminum phosphate and a graphene layer. The invention also discloses a preparation method of the material. The preparation method comprises the following steps of: adding 52-54% by mass of phosphoric acidinto an aluminum isopropoxide ethanol solution, adding a solution with zirconium and cerium concentrations of 0.1 mol/L and a surfactant, uniformly mixing, and regulating the PH value to 8.0-8.5 by using an alkaline complexing agent to prepare sol, and carrying out a hydrothermal reaction on the sol to obtain a precipitate, drying the precipitate, and carrying out heat preservation at 450-650 DEGC for 5-7 h to obtain the cerium and zirconium doped mesoporous aluminum phosphate powder. The lithium ion battery positive electrode material, the cerium and zirconium doped mesoporous aluminum phosphate powder, graphene, polyethylene glycol and N-methyl pyrrolidone according to a mass ratio of (40-100): (0.5-10): (0.1-10): (0.1-10): (50-200) are mixed uniformly, and the temperature of 450-550 DEG C in nitrogen for 3-5 hours is kept. The surface of the lithium ion battery composite material is coated with cerium and zirconium doped mesoporous aluminum phosphate, and the lithium ion battery composite material has good conductivity, stability and cycle performance.