435results about How to "Reduced compressive strength" patented technology

The invention relates to a method of manufacturing a composite acoustic panel employed in an inlet passage of a gas turbine engine (1). The acoustic panel comprises a permeable face-layer (8), an impermeable backing sheet (9) and a sound absorbing layer (10) disposed therebetween. The method comprises a double polymerisation process for the face-layer and the remainder of the acoustic panel and finally a perforation step to perforate the face-layer according to a pre-determined perforation distribution (11.1, 11.2, 11.3, 11.4, 11.5).

A coal gangue-fly ash foam concrete relates to lightweight foam concrete. The invention is composed of coal gangue, fly ash, cement, lime, gypsum, filler and foaming agent. The invention utilizes coal gangue and fly ash industrial waste, which not only reduces product cost but also saves natural resources, and its product also has low cost, high strength, low thermal conductivity, good heat insulation performance, and can be directly plastered after masonry, etc. features. Therefore, the product of the present invention can be widely used in the single thermal insulation wall body (body of wall self-insulation and heat insulation) of outer wall, the internal and external partition wall of frame structure, the rear board wall of large closet; Inner wall of cold storage; thermal insulation layer of floor and roof; thermal insulation board.

Energy absorbing structure disposed beneath the cargo area of an aircraft provides maximum energy absorption and structural strength using carbon fiber reinforced epoxy composites. The energy absorbing structure uses laminated stanchions having ply drop-offs to produce stable, progressive crushing of the stanchions during a wheels-up crash landing. Integrally formed flanges on the stanchions allow direct mounting of the stanchions on the structural members of the aircraft, without the need for specialized fittings.

The invention provides a high-ductility cement-based composite material. The high-ductility cement-based composite material is prepared with the following raw materials by weight: 71.8-85 parts of base material, 12.9-25.2 parts of water, 0.89-2.67 parts of fiber and 0.11-1.23 parts of admixture, wherein the fiber is composed of two or more of polypropylene fiber, polyvinyl alcohol fiber, polyethylene fiber, aromatic polyamide fiber and glass fiber; the weight ratio between the polypropylene fiber, the polyvinyl alcohol fiber, the polyethylene fiber, the aromatic polyamide fiber and the glass fiber, and the total fiber is 15-89.5%, 0-68.4%, 0-75.6%, 0-73.5%, and 0-56.4% respectively. The high-ductility cement based composite material is high in compressive strength and low in preparation cost; the compressive strength can be up to higher than 50.5 MPa; the preparation cost is reduced to 15-50% of that of the prior art. The invention further provides a preparation method of the high-ductility cement based composite material.

Polyurethane foams which are highly flame resistant are described, as well as the production of such polyurethane foams by the reaction between a natural polyol, such as sucrose or a blend of mono- or disaccharides in place of the standard hydrocarbon-based polyol component, a polyisocyanate and water in the presence of a suitable polyurethane forming catalyst and a flame retardant, and optionally one or more components such as surfactants and/or emulsifiers. The resultant polyurethane foam has a bio-based solid content ranging from about 17% to 30%, may be formulated in a variety of foam densities for a variety of applications, and exhibits a high degree of fire and burn resistance, as exhibited by the flame spread index and the smoke spread values.

The invention pertains to the technical field of rare earth magnetically hard material, in particular to a multi-main-phase Nd-Fe-B type permanent magnet with high crack resistance and high coercive force and a preparation method thereof.A final magnet contains multiple differently-sized hard-magnetic main-phase particles having different anisotropic fields HA. Different main-phase particles account for different volume fractions and are differently distributed, wherein Nd denotes a red earth element having the most content based on the mass percent. According to mass percent, the chemical formula of the permanent magnet is expressed as (Dd, Re) aFe100-a-b-cBbTmc. By respective selection, different types of main-phase materials such as (Nd, Pr)-Fe-B, (PR, La, Ce)-Fe-B, (Dy, Tb, Ho, Gd, Er)-Fe-B in the ratio of 2:14:1 in order to prepare corresponding coarse magnetic powder, thin magnetic powder and magnetic nanocrystalline powder. Power is utilized for absorbing hydrogen and controlling oxygen. Liquid-phase sintering technology on the pressurized condition at low temperature is adopted for preparation. The multi-main-phase Nd-Fe-B type permanent magnet with high crack resistance and high coercive force and the preparation method thereof have following beneficial effects: a large piece of magnet does not easily have crack; crack resistance of the magnet is improved; high coercive force and high magnetic energy product are obtained; and the preparation technology is suitable for scale production in engineering.

A tread (B) provided with a tread pattern formed of a plurality of elements in relief (1, 10) which are defined by grooves and/or incisions (2), this tread pattern comprising on each of its edges, that is to say axially furthest to the outside of the tread, an edge rib (1) of circumferential orientation defined axially to the inside by a groove (2) of the same general orientation and of depth H, this tread furthermore comprising, axially to the outside of each edge rib (1), a rib (3) offset relative to the outer contact surface (11) of the neighboring edge rib (1) by a distance d other than zero, this offset rib (3) being separated from the edge rib (1) by a groove (4) of a depth identical or close to the depth H of the groove (2) defining the edge rib (1), wherein the tread comprises, on either side where a sacrificed rib (3) is formed, a plurality of channels (5) opening on to the lateral faces of the tread, these channels (5) being extended in the tread until they open into the groove (4) between the offset rib (3) and the neighboring edge rib (1).

A heat pump device 20 includes an air conditioning control device 22 configured to switch the heat pump device 20 among a plurality of operation modes including an air-heating operation mode in which an indoor heat exchanger 32 serves as a radiator and an outdoor heat exchanger 33 serves as a heat absorber, and an air-cooling operation mode in which the indoor heat exchanger 32 serves as a heat absorber and the outdoor heat exchanger 33 serves as a radiator. The air conditioning control device 22 switch a refrigerant pipe such that refrigerant is, in the air-cooling operation mode, supplied to part of the outdoor heat exchanger 33 serving as a refrigerant inlet in the air-heating operation mode.

The invention discloses a phenolic lignin-based modified foaming phenolic resin, foamed plastic and a preparation method of the phenolic lignin-based modified foaming phenolic resin. The foaming phenolic resin comprises phenol, lignin, an acid catalyst, aldehydes, a base catalyst and an acid neutralizer. Compared with the existing lignin-based phenolic resin and the foamed plastic of the lignin-based phenolic resin, the phenolic lignin-based modified foaming phenolic resin has the beneficial effects that a high-activity lignin phenolized liquid is directly adopted to replace phenol for preparing the foaming phenolic resin, so that the foaming phenolic resin has less free formaldehyde (with the content of less than or equal to 0.15%), and has the advantages of being lower in production cost, rapider in curing speed and the like; and compared with the traditional phenolic resin foamed plastic, the foamed plastic prepared by the phenolic lignin-based modified foaming phenolic resin has the advantages of lower coefficient of heat conductivity and higher compression strength.

The present invention relates to a cement-free alkali activated binder in which alkaline inorganic materials are appropriately added to an industrial waste such as blast furnace slag, fly ash, meta kaolin and the like, a method for producing mortar using the same and a method for producing cement-free alkali activated reinforcement mortar. Specifically, the present invention relates to a cement-free alkali activated binder that is not only environmentally friendly as being capable of dramatically reducing the carbon dioxide emission, which has been remained as a problem for producing Portlandcement, but also has an excellent property, a method for producing mortar using the same and a method for producing cement-free alkali activated reinforcement mortar.

The invention belongs to construction material,Which provides material components and weight percentage rate of a baking-free brick with red mud and flyash are: 22-40 of the red mud, 20-35 of the flyash, 20-40 of aggregate, 8-12 of lime and 1-3 of plaster.With the aim of realizing the largest utilization quantity of the red mud and economizing the cost, through the researches and experiments, the invention uses the red mud and the flyash as main material and uses grit and friable rubbles as the aggregate so as to facilitate compressive strength of the products; the lime and the plaster is added to improve plasticity of the blank material, strength of a semi-finished blank brick and the compressive strength of the products. The invention can satisfy the utilization performance of the products and at the same time completely can meet the national standard requirement, thus solving the problem of the environmental pollution caused by the discharge of the red mud in larger sense.

The invention provides a polyurethane semi-rigid foam composition which is formed by the following components in parts by weight: 100 parts of premixed polyether A and 120-170 parts of isocyanate B. The invention also provides a preparation method of the polyurethane semi-rigid foam composition. The polyurethane semi-rigid foam composition provided by the invention has excellent sound absorption effect and low VOC (Volatile Organic Compounds) content and is especially suitable for automobile roofs.

A method of making cement from tailings or rock fines containing silicate or siliceous compounds includes grinding the tailings or rock fines to a size in the range of from about -250 to about 425 mesh to produce ground pozzolan. The ground pozzolan is mixed with Type 1 normal Portland cement or Type 3 high early strength Portland cement in a ratio of at least about 0.1:1 by weight to produce a blended cement.