38results about How to "Little change in composition" patented technology

Provided are: a working medium for a heat cycle, said working medium containing 1,2-difluoroethylene and exhibiting high stability, reduced environmental impact, and cycle performance that can replace that of R410A (a pseudo-azeotropic mixed refrigerant including difluoromethane and pentafluoroethane at a mass ratio of 1:1) and 1,1,1,2-tetrafluoroethane; a composition for heat cycle system, said composition using the medium; and a heat cycle system using the composition. The working medium for a heat cycle is characterized by the inclusion of 1,2-difluoroethylene and at least two types of hydrofluorocarbon selected from the group of hydrofluorocarbons that include a carbon-carbon double bond other than a saturated hydrofluorocarbon and 1,2-difluoroethylene.

The present invention is a continuous founding-type melt ingot manufacturing process in which used is a plasma arc melting furnace in which a plasma arc column is formed between an electrode torch disposed inside and at an upper part of a vacuum chamber and a water-cooled copper crucible which is provided with a cavity having a cross sectional area S1 and which is disposed inside and at a lower part of the chamber. While the end portion of a raw material rod formed of a platinum group alloy is inserted into the plasma arc column and melted, the melted material is caused to drip onto a base material inside of the water-cooled copper crucible and form a molten pool. While the height of the liquid surface of the molten pool is maintained at a constant height by lowering the base material, the bottom portion of the molten pool is caused to solidify. The horizontal cross-sectional area S (mm2) and the length L (mm) of the melt ingot satisfy S1>=S>500, L>4 radical sign (S / Pi), the internal pressure of the chamber at the time of melting is at least 0.8atm, and the lowering speed is no more than 10mm / min.

The invention provides a preparation method of gradient zirconium boride ultrahigh-temperature ceramic. The preparation method is characterized by comprising the following steps of: 1) preparing casting sheets with different components respectively by a casting method, namely adding a binder and a plasticizer into a solvent to stir uniformly, adding zirconium boride ceramic powder respectively tostir uniformly to form casting materials, and performing casting forming; 2) slicing; 3) overlapping the slices sequentially according to the component size of the zirconium boride, placing the slices into a graphite grinding apparatus, and then performing vacuum degreasing, wherein the layer number is more than 15; the mass percentage of the zirconium boride in the zirconium boride ceramic powder of each layer of casting slice is reduced sequentially; the mass percentage of silicon carbide is not changed or is reduced; the mass percentage of zirconium oxide is increased sequentially; and themass percentage sum of three components in the zirconium boride ceramic powder of each casting slice is 100 percent; and 4) performing hot pressed sintering to prepare the gradient zirconium boride ultrahigh-temperature ceramic with a heat insulation function. The preparation process is simple and the cost is low. By the preparation method, an ultrathin ceramic part can be prepared and has fracture toughness of up to 8 MPa.m1 / 2.

This invention relates to a changeover method for continuously manufacturing propylene by C4+ alkenes catalytic cracking. The method adopts a reactor with a set of parallel fixed beds. Each fixed bed is operated according to a certain interval, and the products of all fixed bed are mixed and sent to the next process so that the reactant of the next process has stable composition. The method solves the problems of low catalyst activity and large change of product composition at the beginning and end of reaction, which leads to difficulties in stable quality and next process. The method can be used in propylene industrial manufacture by C4+ alkenes catalytic cracking.

A preparation method for a vertical anisotropy iron-base soft-magnetic film is to prepare an iron-base soft-magnetic film on a chip with a RF magnet-control spraying method then to anneal it under spraying method then to anneal it under suitable temperature after the preparation and to cool it without extra outer magnetic field or in the outer magnetic field vertical to the film face to get a vertical anisotropy iron-base soft-magnetic film, among which, the chip is a carrier chip or a silicon chip and the target material is an iron -base soft magnetic alloy.

The present invention provides a kind of etchant, it contains hydrofluoric acid (A), ammonium fluoride (B), by the acid (C1) that has higher pKa than hydrofluoric acid (pKa=3.17) and has higher than ammonia ( The salt (C) and water (D) obtained from the base (C2) of pKa (pKa=9.24) have little change in composition due to the evaporation of the chemical solution, and the exchange frequency of the chemical solution is low, and can be uniform even over a long period of time. to etch the silicon oxide film.

The invention provides a polysulfone dialysis membrane, and a production method and an application thereof. A polysulfone-polyethylene glycol block copolymer in the production method is used as a pore forming agent. The production method comprises the following steps: dissolving 10-25 parts by weight of polysulfone and 1-25 parts by weight of the polysulfone-polyethylene glycol block copolymer in 60-100 parts by weight of an organic solvent, and mixing above materials and the organic solvent to prepare a membrane casting solution; and cooling and defoaming the membrane casting solution, pouring the obtained solution onto a substrate, scraping a membrane, volatilizing the organic solvent in the membrane casting solution, placing the volatilized solution, solidifying the solution to form a membrane, and immersing the formed membrane in water to completely displace the organic solvent in the membrane in order to obtain the polysulfone dialysis membrane. The polysulfone-polyethylene glycol block copolymer used as the pore forming agent promotes the formation of membrane pores, so the pore forming agent is firmly anchored to the surface of the polysulfone base membrane, the loss problem of a hydrophilic pore forming agent is solved, and the membrane is endowed with a permanent hydrophilic property; and the polysulfone dialysis membrane also has the advantages of high membrane flux, high flux recovery rate and good stability.