152results about How to "High phase transition temperature" patented technology

A RE zirconate coating material for preparing high-temp heat barrier layer has a chemical formula: A2B2O7, where A is chosen from La, Nd, Sm, Gd, Dy, Er and Yb and B is Zr. It is prepared through ball grinding of raw materials, baking, die pressing, and reaction in air at 1550-1650 deg.C. It has low heat conductivity and high high-temp stability.

The invention relates to a method for preparing a graphene and inorganic salt high-temperature phase change composite material. The method comprises the following steps of: (1) preparing graphene sol; (2) preparing an inorganic salt solution, adding a surfactant, and mixing uniformly; (3) adding the graphene sol into the inorganic salt solution, and stirring until the graphene sol and the inorganic salt solution are mixed uniformly to obtain a composite material preform; (4) putting the composite material preform into an ultra-low-temperature freezer, quickly freezing to form a solid and taking out; (5) putting the solid-state composite material preform into a vacuum freezing dispersion drying instrument and drying; and (6) taking out after the drying of the composite material preform is finished, and calcining until the moisture is completely removed to obtain a grapheme/inorganic salt phase change composite material. Compared with the prior art, the method has the advantages that: the process is reasonable, easy to operate and low in cost; and the prepared grapheme/inorganic salt phase change composite material has the advantages of high coefficient of heat conductivity, high energy storage density and the like, has excellent performance, can meet different application requirements, and is suitable for industrialized production.

The invention relates to a device for heat shaping of thin-walled titanium alloy parts. A first pressing mechanism is fixed at one end of a body, and a second pressing mechanism is fixed at the other end of the body. Two clamping mechanisms are mounted in the middle of the body. Two clamping plates of a lateral ejection mechanism are fixed on two lateral surfaces of the body respectively and located between the first pressing mechanism and the clamping mechanisms. A width inner-supporting mechanism is located between the two clamping plates of the lateral ejection mechanism, one end of the width inner-supporting mechanism is mounted in a to-be-shaped part, and cavity inner-supporting mechanisms are mounted on the upper surface and the lower surface of the width inner-supporting mechanism. One ends of the cavity inner-supporting mechanisms are mounted in the clamping mechanisms, so that a support body with a wedge-shaped inner cavity is formed in the to-be-shaped part. By the device, utilization rate of a heat treatment furnace is increased, and cost of vacuum heat shaping is lowered. Since the to-be-shaped parts are clamped symmetrically, main stresses of a tooling are symmetric in direction and offset each other, stress state of the tooling is improved, and deformation resistance of the tooling is enhanced indirectly.

The invention belongs to the technical field of 4D printing additive manufacturing, and discloses a 4D printing method of a nickel-titanium-based ternary shape memory alloy. The 4D printing method ischaracterized in that a selective laser melting technology is adopted for printing gas atomized prefabricated NiTiZr ternary alloy powder, and a component obtained through printing has the shape memory function; and the laser energy density is changed by changing the technological parameters adopted in the selective laser melting technology, and therefore the changes of the structure and performance of the printed piece are regulated and controlled. According to the 4D printing method, the ternary component Zr is introduced into an existing nickel-titanium binary alloy, the martensite phase transformation temperature is obviously increased, the selective laser melting technology is adopted for forming, and complex parts uniform in structure and high in density can be obtained while the excellent shape memory performance and mechanical performance are guaranteed.

The invention provides a movable heat storage and discharge device based on pulsating heat pipes and a heat storage and discharge method thereof. The heat storage and discharge device comprises a shell, a heating chamber, a phase-change material chamber, a cooling chamber and the pulsating heat pipes, wherein the heating chamber, the phase-change material chamber, the cooling chamber and the pulsating heat pipe are all arranged in the shell; the heating chamber, the phase-change material chamber and the cooling chamber are separated by stainless steel partitions; at least one group of pulsating heat pipes pass through the partitions and are arranged in the shell; the parts, which are arranged in the heating chamber and the cooling chamber, of the pulsating heat pipes include straight pipe sections and elbows, and the parts, which are arranged in the phase-change material chamber, of the pulsating heat pipes are straight pipe sections; the parts, which are arranged in the heating chamber, of the pulsating heat pipes are evaporating sections, the parts, which are arranged in the phase-change material chamber, of the pulsating heat pipes are insulation sections, and the parts, which are arranged in the cooling chamber, of the pulsating heat pipes are condensation sections; and fluid inlets and outlets are formed in one end of the cooling chamber and the heating chamber. Phase-change heat transfer of working media in the pulsating heat pipes and phase-change heat storage of phase-change materials are used, so that waste heat is absorbed, stored, transferred and released, thereby effectively recycling the waste heat.

The invention relates to a Ge2Sb2Te5/Ga30Sb70 nanometer multi-layer composite phase-change film for a multilevel storage phase-change memory. A monolayer Ge2Sb2Te5 film and a monolayer Ga30Sb70 film in the Ge2Sb2Te5/Ga30Sb70 nanometer multi-layer composite phase-change film material are alternately ranged to form a multi-layer film structure, the thickness of the monolayer Ge2Sb2Te5 film and the thickness of the monolayer Ga30Sb70 film are respectively 10-133nm, and the total thickness of the Ge2Sb2Te5/Ga30Sb70 nanometer multi-layer composite phase-change film material is 90-200nm. When the Ge2Sb2Te5/Ga30Sb70 nanometer multi-layer composite phase-change film provided by the invention is applied to the phase-change memory, multilevel storage can be realized; and simultaneously, the Ge2Sb2Te5/Ga30Sb70 nanometer multi-layer composite phase-change film has higher heat stability and stronger data retention performance.

The invention relates to a diesel vehicle oxidized form catalyst having low temperature activity and a preparation method thereof.The catalyst comprises a carrier and a coating applied to the carrier, the coating is loaded with noble metal, the coating comprises tungsten-aluminum silicon composite oxide and molecular sieves, the noble metal is one of Pt and Pd or a mixture of the two types of substances, the coated weight of the coating is 80-180 grams/liter, and the coated weight of the noble metal is 0.5-4.5 grams/liter.The preparation method comprises the steps of firstly, preparing the tungsten-aluminum silicon composite oxide through an equivalent-volume impregnation method, then making slurry with the molecular sieves and the tungsten-aluminum silicon composite oxide according to the mass ratio of 1: (2-10), adding the noble metal Pt and Pd, finally immersing the carrier into the slurry, and conducting drying and sintering, so that the diesel vehicle oxidized form catalyst is obtained.The preparation method of the catalyst is simple, the steps are easy to operate, the prepared diesel vehicle oxidized form catalyst is low in combustion temperature, high in conversion rate and good in thermal stability, good capability for oxidizing HC and CO in tail gas of a diesel vehicle is achieved, and good sulfur resistance is achieved.

The invention provides a manganese-based oxide catalyst. The catalyst is characterized in that the catalyst is a mullite oxide having a general formula of RMn2O5, wherein R is Pr, Nd, Eu, Gd, Tb, Dy,Ho, Er, Tm, Yb, Lu, Y or Bi. The catalyst can effectively catalytically oxidize nitrogen monoxide into nitrogen dioxide at a low temperature, has good aging resistance and good durability, and can effectively remove nitrogen oxides from automobile exhaust gas. A method for preparing the oxide has the advantages of few raw materials, simple steps, and convenience in operation. The hydrothermal synthesis method effectively reduces the preparation temperature of mullite to greatly save energy, and also has the characteristics of short preparation period, low device requirements and easiness in promotion.

The invention relates to a preparation method for a magnetic shape memory alloy, in particular to a preparation method for a high strength Ni50Mn34In16 magnetic memory alloy. The high strength Ni50Mn34In16 is prepared according to the following steps of material taking according to the atomic percent, mixing, forming, degreasing and sintering, and then the high strength Ni50Mn34In16 is obtained. The Ni50Mn34In16 alloy prepared by the method has higher fracture strength and fracture strain, the grain size of the magnetic shape memory alloy is tiny so as to drive the threshold value of a magnetic field to be reduced, the excellent magnetic property is achieved, and the train of thought is expanded for application of the high temperature and high plasticity shape memory alloy.

The invention provides a rare-earth magnetic material with high magnetocrystalline anisotropy and large magnetoelastic strain and a preparation method thereof. The material has high magnetocrystalline anisotropy, and can provide large magnetocrystalline anisotropy under the action of an external magnetic field, so that the material is subjected to twin crystal rearrangement under the martensite state, so as to generate large magnetoelastic strain. The chemical formula of the alloy is CoxNiyAlzErj, wherein x is smaller than or equal to 42 and greater than or equal to 28; y is smaller than or equal to 32 and greater than or equal to 25; z is smaller than or equal to 35 and greater than or equal to 23; j is smaller than or equal to 10 and greater than or equal to 0.5; x+y+z+j is 100; x, y, z and j represent the mole percentage content. Compared with the existing alloy, the high-temperature magnetic shape memory alloy CoxNiyAlzErj disclosed by the invention has high magnetocrystalline anisotropy, high magnetoelastic strain and good mechanical property, and has important application in the fields of an actuator, a magnetosensitive element and a miniature electromechanical system.

The invention discloses an Sr and Mg doped amorphous apatite material and crystalline apatite material, belonging to the field of biomedical materials. The different concentrations of Sr and Mg doped amorphous apatite material is rapidly prepared by using Ca(NO3)2, Mg(NO3)2, Sr(NO3)2, (NH4)2HPO4 and ammonia-water as raw materials and then is transformed to the different concentrations of Sr and Mg doped nano calcium-deficient hydroxyapatite or nano tricalcium phosphate material through heat treatment. Compared with traditional hydroxyapatite crystalline materials, the amorphous material has higher solubility. The amorphous apatite material and the crystalline apatite material have the beneficial effects that after Sr and Mg doping, Sr can achieve the effects of promoting new bone formation, reducing reabsorption of bone, adjusting calcium metabolism and reducing the activity of osteoclast, and Mg can achieve the effects of affecting early growth of bone substances and regulating growth and remodelling of the bone substances; therefore the synthesized amorphous apatite and the crystallized product thereof have important roles in the fields of bone repair and bone transplantation.

A pulsating heat pipe active thermal protection structure coupled with ablative resistant materials comprises a thermal grooming device and ablative resistant materials, wherein the ablative resistantmaterials are coated on the periphery of the thermal grooming device and comprise an inner layer and an outer layer; the inner layer is a flexible foam, and the outer layer is a high thermal conductivity carbon/carbon material; the thermal grooming device comprises a cooling panel, a pulsating heat pipe group and a phase change cold storage box; the cooling panel is bonded with the ablative resistant materials; the pulsating heat pipe group is welded with the cooling panel; the phase change cold storage box is welded with the cooling panel and fixed with the end frame of the aircraft; and thepulsating heat pipe extends into the phase change cold storage box. The pulsating heat pipe active thermal protection structure coupled with ablative resistant materials combine ablation-resistant material with the thermal grooming device. By means of the active thermal protection structure of the sharp lead edge of the aircraft, ablation is reduced or no ablation occur, and the aerodynamic shapeof the aircraft is changed little, and the aerodynamic characteristic of the aircraft with high lift-to-drag ratio is maintained, and the problem of material failure caused by the local high heat ofthe aircraft is solved, and the extreme distribution of temperature is avoided, and the long-time heat insulation is realized.

The invention relates to phosphor doping type nano titanium dioxide having efficient sunlight catalytic capability and a preparation method thereof. The average grain size of the phosphor doping type nano titanium dioxide is no more than15nm, and the specific surface of the nano titanium dioxide is 126.9m<2>/g. The preparation method is: taking tetrabutyl titanate as titanium source and phosphoric acid as phosphorus source, and using sol-gel method to synthesize phosphor doping type nano titanium dioxide grains; and grinding the obtained solid to be fine, and calcining at 400-900 DEG C to obtain P doping nano titanium dioxide grains. The best calcination temperature is 500 DEG C. The invention only requires to add phosphoric acid in alcoholic solution of tetrabutyl titanate to obtain phosphor doping nano titanium dioxide grains. When the nano grains are used for performing photocatalytic degradation on dye rhodamine B, sunlight can be directly adopted as the light source, and under the same conditions, the efficiency of photocatalytic degradation can exceed the commercial P25.

A light condensation solar water heater device based on phase-change heat accumulation comprises a cylindrical lens light condenser, a vacuum heat collecting pipe, a phase-change medium, two aluminum slot walls, a water heat substrate, a heat exchanging pipe, an aluminum alloy outer frame, reinforcing ribs, a small platform, a cold water main pipe, and a hot water main pipe. The cylindrical lens light condenser covers the uppermost of the vacuum heat collecting pipe. The light rays entering the cylindrical lens light condenser are condensed to form a light focal strip. The lower portion of the cylindrical lens light condenser is connected with the aluminum slot walls of the water heater substrate. The two aluminum slot walls form two plane mirrors in angled opposition. Parts of the light rays refracted by the light condenser is condensed to the vacuum heat collecting pipe, and the other parts, do not project to the vacuum heat collecting pipe, of the light rays are reflected by the two aluminum slot wall plane mirrors and projected to the vacuum heat collecting pipe. The phase-change medium and the U-shaped heat exchanging pipe are disposed inside the vacuum heat collecting pipe. The vacuum heat collecting pipe is fixedly clamped into a clamp groove formed in the water heat substrate.

The invention provides a nematic liquid crystal composition, which comprises 5 to 50 weight percent of nematic liquid crystal composition represented by a formula I, wherein R1 is an alkyl having 1 to 12 carbon atoms or an group formed by substituting a -CH=CH- for one or two nonadjacent groups of the alkyl; and L1, L2, L3 and L4 are Hs or Fs independent from one another; M is F, -CN, -OCF3 or -OCHF2. The composition of the invention has excellent performance and extremely short total response time (ttot=ton+toff), particularly excellent response in a low temperature state, such as 30 DEG C below zero. In addition, the composition has high phase-transition temperature, a clearing point up to 12 DEG C and excellent temperature dependence and can be used in 16 channels at a working temperature of between 40 and 80 DEG C below zero and TN-LCDs at a temperature of below 40 and 80 DEG C below zero.

The present invention relates to a liquid crystal composition having a high-speed response property and a liquid crystal display using the same, more particularly to a liquid crystal composition, wherein the liquid crystal has a high phase transition temperature, large birefringence index and modulus of elasticity, and a wide operable nematic temperature range, so that a high-speed response can be obtained to be useful for many liquid crystal devices including LCDs, and a liquid crystal display using the same.