198results about How to "Short diffusion path" patented technology

LiFePO₄ flakes for a Li-ion battery and a method for manufacturing the same are disclosed. The LiFePO₄ flakes of the present invention have a thickness of 5 nm-200 nm, and the angle between the flat surface normal of the flake and the Li-ion diffusion channel is 0°-80°. In addition, according to the present invention, the LiFePO₄ flakes with short Li ion diffusion path can be prepared through a simple process. Hence, not only the charge-discharge efficiency of the Li-ion battery can be improved by use of the LiFePO₄ flakes of the present invention, but also the cost of the Li-ion battery can be further reduced.

A stent includes a stent body having a circumference and struts disposed helically about the circumference. Each of the struts has a strut length and a ratio of a number of the struts around the circumference to the strut length is greater than 800 per inch, in particular, over 1000 per inch. A method for manufacturing a helical stent includes the steps of providing a stent body with struts disposed about the circumference thereof in turns and with bridges connecting the struts in adjacent turns. The stent body is expanded and, thereafter, some of the bridges, in particular, sacrificial bridges, are removed.

The invention discloses a hierarchical pore ZSM-5 molecular sieve and a synthetic method thereof. The hierarchical pore ZSM-5 molecular sieve is formed by the accumulation of crystalline grains with order nano-layered structures and is integrally structured. The synthetic method comprises the following steps of: with quaternary ammonium salt as a structure-directing agent (SDA), tetraethoxysilane (TEOS) as a silicon source, aluminium isopropoxide (AIP) as an aluminum source, and potassium hydroxide (KOH) as an alkali source, adding a cationic surface active agent (CSF) to prepare a synthetic liquid with the molar ratio of (20-100) SiO2: (1-3) Al2O3: (10-30) SDA: (10-50) KOH: (1,000-3,000) H2O: (1-10) CSF; adding 10 to 20% of Silicalite-1 molecular sieve seed crystal gel; performing hydrothermal crystallization according to the conventional method; processing a product by washing, drying and roasting to obtain the ZSM-5 molecular sieve. The molecular sieve is an agglomeration which is formed by the self-assembly under mutual effect of CSF, seed crystal gel and an inorganic species and is of a lamella and hierarchical zeolite structure; the molecular sieve is relatively high in specific surface area, relatively short in a diffusion path and relatively high in stability. The preparation method also has the advantages of high degree of crystallinity, high yield and simple operation steps, and is easy to separate.

A stent includes a stent body with a diameter of between approximately 4 and 12 mm and a length of between approximately 10 and 250 mm. S-shaped struts are disposed helically about the circumference along helical turns. The struts have straight portions and curved portions connecting respectively adjacent ones of the straight portions. Bridges connect the struts in adjacent ones of the turns. The bridges include connecting bridges and a given number of sacrificial bridges before being expanded, and the connecting bridges and less than the given number of the sacrificial bridges after being at least partially expanded. A method for manufacturing a helical stent includes the steps of providing a stent body with struts disposed about the circumference thereof in turns and with bridges connecting the struts in adjacent turns. The stent body is expanded and, thereafter, some of the bridges, in particular, sacrificial bridges, are removed.

A positive electrode active material includes a layered lithium-manganese oxide represented by the general formula Li_2-xMn_1-yO_3-p, where 0≦x≦2/3, 0≦y≦1/3, and 0≦p≦1, the lithium-manganese oxide having a full width half maximum of a peak of the (001) crystal plane, as determined by an X-ray diffraction analysis, of 0.22° or greater, and an average particle size of 130 nm or less.

The invention discloses a hierarchical pore ZSM-5 molecular sieve with a nanosheet layer structure and a synthesis method thereof; the hierarchical pore ZSM-5 molecular sieve with the nanosheet layer structure is formed by cluster stacking of nanosheet layers with the thickness of 30 to 50 nm; an amphiphilic cationic surfactant is used as a structure directing agent, potassium hydroxide or sodium hydroxide is used as an alkali source, a synthesis solution with the molar ratio of (20-100)SiO2:(0.4-3)Al2O3:(10-50)ROH:(1000-3000)H2O:(1-10)SDA is prepared and then is subjected to hydrothermal crystallization according to a conventional method, and the product is washed, dried and roasted to obtain the ZSM-5 molecular sieve. The molecular sieve is the hierarchical pore ZSM-5 molecular sieve having the nanosheet layer structure and formed by self assembly of the amphiphilic cationic surfactant and an inorganic species through interaction, has the characteristics of large specific surface area, short diffusion path and good stability; and the preparation method has the advantages of high degree of crystallinity and simple operation.

The invention discloses a production method for manganous/magnesium silicate of chargeable magnesium battery positive pole material, which is the manganous/magnesium silicate of chargeable magnesium battery positive pole material using molten salts as reaction medium and having the characteristics of quickening up reaction speed, shortening reaction cycle, simplifying synthesis course, reducing synthesis cost, small synthesis particle size and symmetrical distribution of the particles. The material exhibits remarkable electrochemical charge and discharge effects, the steady discharge platform works up to 1.6V and 1.1V(vs.Mg/Mg<2+>); on the charge and discharge conditions of C/20 current density, the discharge capacitance can reach 289.3mAh*g<-1>(theoretical capacitance is 92%). In contrast to the relatively ideal positive pole material Mo3S4 of the current chargeable magnesium battery, the manganous/magnesium silicate positive pole material produced by the molten salt process has the advantages of simple production, large capacitance, high discharge voltage platform and the like.

The present invention discloses novel methods for producing highly porous ceramic and/or metal aerogel monolithic objects that are hard, sturdy, and resistant to high temperatures. These methods comprise preparing nanoparticulate oxides of metals and/or metalloids via a step of vigorous stirring to prevent gelation, preparing polymer-modified xerogel powder compositions by reacting said nanoparticulate oxides with one or more polyfunctional monomers, compressing said polymer-modified xerogel powder compositions into shaped compacts, and carbothermal conversion of the shaped xerogel compacts via pyrolysis to provide the highly porous ceramic and/or metal aerogel monolithic objects that have the same shapes as to their corresponding xerogel compact precursors. Representative of the highly porous ceramic and/or metal aerogel monolithic objects of the invention are ceramic and/or metal aerogels of Si, Zr, Hf, Ti, Cr, Fe, Co, Ni, Cu, Ru, Au, and the like. Examples include sturdy, shaped, highly porous silicon carbide (SiC), silicon nitride (Si₃N₄), zirconium carbide (ZrC), hafnium carbide (HfC), chromium carbide (Cr₃C₂), titanium carbide (TiC), zirconium boride (ZrB₂), hafnium boride (HfB₂), and metallic aerogels of iron (Fe), nickel (Ni), cobalt (Co), copper (Cu), ruthenium (Ru), gold (Au), and the like. Said aerogel monolithic objects have utility in various applications such as, illustratively, in abrasives, in cutting tools, as catalyst support materials such as in reformers and converters, as filters such as for molten metals and hot gasses, in bio-medical tissue engineering such as bone replacement materials, in applications requiring strong lightweight materials such as in automotive and aircraft structural components, in ultra-high temperature ceramics, and the like.

A preparation method for a magnetic MOFs solid-phase extractant comprises the following steps: 1, employing a coprecipitation process to prepare a magnetic Fe3O4 nanosphere with the particle size of 10-20 nm; 2, employing Stober silica gel coupling process to prepare Fe3O4@SiO2 with a shell-core structure; 3, employing an in-situ precipitation process to prepare Fe3O4@SiO2@Cu(OH)2; 4, employing an in-situ conversion manner to synthesize Fe3O4@SiO2@HKUST-1; and 5, performing post-functionalization on Fe3O4@SiO2@HKUST-1 synthesized in the step 4 to synthesize the Bi-I modified magnetic MOFs solid-phase extractant. The advantages comprise that the provided method is simple, convenient, low in cost and friendly to environment. The prepared magnetic MOFs solid-phase extractant has the advantages of rapid adsorption speed, large adsorption capacity, high removal efficiency and the like, and efficient removal of low-concentration Hg<2+> can be realized.

The invention relates to a catalyst for hydrogen selective oxidation reaction during phenyl ethylene production, and mainly solves the problems of low using efficiency and short service life of the catalyst, and high raw material loss in the prior art. The catalyst for the hydrogen selective oxidation reaction during the phenyl ethylene production comprises a kernel of an inert carrier and a layered composite carrier which is combined on the kernel and consists of an outer layer of a porous coating material, wherein the outer layer of the layered composite carrier is loaded with at least one platinum series metal selected from ruthenium, rhodium, palladium, osmium, iridium and platinum, at least one dressing agent selected from alkali metals and alkaline-earth metals, and an assistant catalyst selected from one of IVA compounds and at least one of lanthanide series compounds. The technical proposal solves the problems well, and the catalyst can be applied in the industrial production of the hydrogen selective oxidation reaction in a process of producing phenyl alkene by ethylbenzene dehydrogenation.

The invention discloses a ZSM-5 molecular sieve with a nanosheet layer structure and a synthesis method thereof; the ZSM-5 molecular sieve with the nanosheet layer structure is formed by cluster stacking of nanosheet layers with the thickness of 10 to 30 nm; an organic quaternary ammonium salt and an amphiphilic cationic surfactant are used as structure directing agents and template agents, potassium hydroxide or sodium hydroxide is used as an alkali source, a synthesis solution with the molar ratio of (20-100)SiO2:(0.4-3)Al2O3:(10-30)TPA:(10-50)ROH:(1000-3000)H2O:(1-10)SDA is prepared through a conventional hydrothermal crystallization method, and the product is washed, dried and roasted to obtain the ZSM-5 molecular sieve with the nanosheet layer structure. The molecular sieve is an MFI type molecular sieve having the sheet layers and multi-level pore channel structure and has the characteristics of relatively large specific surface area, relatively short diffusion path and relatively good stability.

The invention belongs to the technical field of inorganic materials, and in particular relates to a preparation method of a nano-rod-shaped ZSM-48 molecular sieve. The method comprises the following steps: mixing a silicon source, an aluminum source, an alkali source, an organic template and a water phase by virtue of adopting a hydro-thermal synthesis method, and stirring into a gel-like mixture used as a raw material for synthesizing the ZSM-48 molecular sieve. The chemical composition of the nano ZSM-48 molecular sieve with high degree of crystallinity is TO2:aY2O3:bM2/nO, wherein T represents at least one quadrivalent element, Y represents at least one trivalent element, M represents at least one alkaline metal (or) alkaline-earth metal element of which the valence state is n. Prepared ZSM-48 disclosed by the invention not only has neat appearance, relatively short diffusion process, ultra-high degree of crystallinity and relatively rich specific surface area, but also can be used for improving the whole catalytic utilization efficiency of the molecular sieves.

The invention discloses a hydrogenation catalyst using BYD hydrogenation to prepare BDO and a method using BYD hydrogenation to prepare BDO. The method includes: preparing metal alloy particles; using alkali liquor to activate the metal alloy particles; using deionized water to wash the activated metal alloy particles; using a molybdenum salt aqueous solution to perform subsequent impregnation modification on the washed metal alloy particles; using deionized water to wash the impregnated and modified metal alloy particles to obtain the granular Raney nickel catalyst; using the granular Raney nickel catalyst to perform catalytic hydrogenation reaction on BYD in a fixed bed reactor. The method has the advantages that the method is simple in process, promising in application prospect and huge in economic benefit, and the hydrogenation effect is improved evidently.

The invention discloses a rechargeable magnesium cell anode material and a preparation method thereof. The anode material is magnesium ferrosilite which has the chemical structural formula of MgxFeySiO4, wherein x is higher than and equal to 1 and lower than or equal to 1.2, and y is more than or equal to 0.8 and less than or equal to 1. Nanometer silica dioxide is taken as a silicone source; and the magnesium ferrosilite which is the rechargeable magnesium cell anode material obtained through a molten salt method shows the good electrochemical charge and discharge behavior. In the electrolyte of 0.25mol.L<-1>Mg(AlCl2BuEt) 2/THF and with the discharge rate of 0.2C, the discharge platform reaches 1.5V(vs.Mg/Mg<2+>) and the discharge capacity reaches 151.7mAhg<-1>. In the electrolyte of 0.4mol.L<-1> [Mg2Cl3] + [AlPh2Cl2] -THF and with the discharge rate of 0.4C, the discharge platform reaches 1.2V(vs. Mg/Mg2+) and the discharge capacity reaches 148.5mAhg-1.

The invention relates to a Mn2P2O7 anode material of a core-shell structured lithium ion battery and a preparation method thereof. The Mn2P2O7 is prepared according to the following steps of: (1) dissolving an organic manganese source and a phosphorus source in deionized water to obtain a mixed solution; (2) adjusting a pH value to be 3 to 8; (3) placing the solution in a water bath at 60 to 90 DEG C, and stirring the solution for 10 to 30 hours to form uniform gel; (4) drying the gel for 4 to 15 hours at 60 to 110 DEG C to obtain a Mn2P2O7 precursor; and (5) placing the Mn2P2O7 precursor in a non-oxidizing atmosphere, sintering the Mn2P2O7 precursor at 350 to 700 DEG C for 4 to 14 hours, and cooling the product to the room temperature, thereby obtaining the Mn2P2O7 anode material of the core-shell structured lithium ion battery. The nanometer rod of the Mn2P2O7 is of a core-shell structure and has high specific area, thereby being favorable for ion transmission and infiltration of an electrolyte to an electrode material; and moreover, the conductivity of the nanometer rod is greatly improved due to uniformly-coated amorphous carbon, and the electrochemical performance of the material is excellent.

The invention discloses a preparation method of a membrane electrode of a fuel cell. The method comprises the steps of coating a transfer medium with a substrate layer; carrying out in-situ reduction-deposition of platinum nanoparticles on the substrate layer and then coating the platinum nanoparticles with a layer of proton conducting polymer to form an electrode catalyst layer; and finally transferring the catalyst layer to a proton exchange membrane by adopting a heat transfer process to prepare a membrane electrode. The invention further discloses the membrane electrode of the fuel cell and an application of the membrane electrode on a cathode or an anode of a proton exchange membrane fuel cell. The problem of contradiction between reduction time and electrochemical active area in thein-situ deposition process of platinum is relatively well solved and the yield of heat transfer is improved. The membrane electrode has the beneficial effects of high catalyst activity and utilizationrate, large electrochemical active area, low gas transmission impedance in the catalyst layer and the like, and is low in production cost, simple and fast in process and high in yield, and massive production is easy to implement.