118results about How to "Strength has" patented technology

The invention discloses a high oil absorbing resin, and a process for preparation comprises utilizing short-chain ester of (metyl group) acrylic acid, long-chain ester of acrylic acid and styrene monomer to be monomers, adding dispersing agent and surface active agent, and getting through suspension polymerization and random copolymerization under the condition of the existence of cross linker and initiating agent. The process for synthesizing has lithe time consumption, which can be industrialized, and high oil absorbing resin which is got has high oil absorbing efficiency, fast oil absorbing speed, and which can be recycled to be repeatedly used.

The invention discloses a dendritic organic-inorganic hybrid water-borne nano polyurethane-epoxy anticorrosive coating and a preparation method thereof. Compositions of the coating mainly comprise dendritic organic-inorganic hybrid water-borne nano polyurethane-epoxy emulsion, anticorrosive pigment and filler, pigment dispersing agent, a film forming aid, a water-based additive, a cross-linking curing agent and deionized water, wherein the dendritic organic-inorganic hybrid water-borne nano polyurethane-epoxy emulsion is prepared by the following steps: prepolymerizing a polyurethane hydrophilic branch; preparing a dendritic polyurethane intermediate product by adopting hyperbranched synthesis technology; inoculating organic-inorganic hybrid into a nano material by adopting a in-situ polymerization; and simultaneously grafting epoxy resin with hydroxyl; and the prepared emulsion is compounded with the anticorrosive pigment and filler and the like to prepare the anticorrosive coating. The anticorrosive coating radically solves the VOC pollution problem of solvent-type anticorrosive coating, and simultaneously solves a series of problems such as poor roughness, weatherability, ageing resistance, alkali resistance and solvent resistance of the conventional water-borne anticorrosive coating.

The invention relates to a manufacturing technique of stereoscopic underglaze multicolor ceramic, which comprises the following steps: carrying out ball milling on a selected ceramic raw material, screening, slurrying, carrying out injection forming on a mold to obtain a required shape, preparing a blank, and carrying out bisque firing to obtain a biscuit; carving out a stereoscopic multilayer plain color picture on the biscuit with a carving tool; dipping a drawing tool into underglaze multicolor pigments, and drawing and decorating on the stereoscopic picture of the biscuit to obtain a colored biscuit; carrying out color depth gradation treatment on the picture of the colored biscuit by using a special brush; and covering a glaze layer on the surface of the colored biscuit subjected to color treatment; and firing the glaze-covered colored biscuit in a kiln again to obtain the finished product. The technique adopts the two modes of biscuit carving and mold carving. The ceramic article prepared by the technique has the advantages of strong stereoscopic effect, abundant colors, high color layering effect and glossy and bright glaze.

The invention discloses a novel sponge body double-waste pervious concrete pavement. The pavement comprises the following layers in order: a surface layer, a connecting layer, a base and a cushion. The connecting layer is sponge body garden waste mortar; the base is novel sponge body double-waste pervious concrete; the sponge body garden waste mortar comprises cement, sand and garden waste; the novel sponge body double-waste pervious concrete comprises cement, sand, garden waste, regenerated stones and a brightener. The sponge body double-waste pervious concrete pavement solves the city garden waste pollution problem, changes waste into valuables, and is good for environmental protection; the pavement has the advantages of water imbibition, water penetration, water storage, permeability and higher strength; the garden waste can be collected conveniently, and concrete, mortar and other materials are saved, so that the pavement is economical.

The invention relates to the casting field, and especially relates to a preparation method for a U-shaped hole in casting. Molding is carried out according to a designed casting structure. A U-shaped hole core is prepared from fibers with high temperature resistance and a metal skeleton, or painting for casting is painted uniformly on a metal skeleton to prepare a U-shaped hole core. The size of the U-shaped hole core is the same as the size of the shaped hole. The U-shaped hole core is placed in the mold during the pouring process. After the casting is taken out, the U-shaped hole core is drawn out, and a U-shaped hole meeting the curvature radius of design requirements can be obtained. The preparation method is advantageous in that, the problem that a U-shaped hole cannot be cast through a conventional casting method is solved.

The invention relates to an HP-CLC energy-saving embedded type light inside and outside wall board and a manufacturing method of the wall board. The wall board is prepared from 30-60 parts by weight of inorganic gel material, 30-45 parts by weight of inorganic low-gel material, 15-30 parts by weight of inorganic heavy framework material, 0.3-0.4 part by weight of toughening fiber, 1-1.5 parts by weight of high-performance activating agent, 0.1-0.3 part of macromolecule initiating agent and 40-50 parts by weight of water. The physical foaming principle is adopted, namely, hollow foams formed by high polymer material are stirred and homogenized into slurry of the inorganic gel material, and the gas is not generated by chemical foaming, so that the produced concrete product has the characteristics of being diversified in varieties, high in yield, stable in performances and durable in weather fastness, having the rate of finished products reaching up to 100%, etc. Furthermore, all the raw materials used in the product can be directly used without additionally processing and grinding, thus having no limitation; and therefore, the cost is saved, and the defects such as environmental pollution and the like can be overcome.

The invention discloses a method for quickly constructing a water gate wall, which comprises five steps of constructing a temporary water barrier, constructing an entity temporary water battier, constructing a filling section, constructing a main water gate wall and constructing an external tunnel of the main water gate wall. Barrel-shaped building blocks are used as the aggregate, water can be got at the construction site, and only barrel bodies and little coacervated single-liquid material are needed to be transported, so that the labor intensity and the transportation volume are both greatly reduced, the construction speed is improved, and plenty of time is saved for rescue construction; the coacervated single-liquid grouting material reacts in the presence of water to generate gel, and the generated gel has certain strength and steady performance, is not decomposable and corrosion resistant, and cannot absorb water; two sides of each barrel body are provided with iron hoops, and the iron hoops of neighboring barrel bodies are fixed through bolts to form a net structure; the barrel bodies are connected with anchor rods on the two sides, the top and the bottom plate of the tunnel, so that the water gate wall can resist the impact of water pressure, the construction quality is effectively ensured, and fast construction for constructing the water gate wall is implemented.

The invention discloses an efficient flame retardant cable sheath material which comprises the following raw materials in parts by weight: 80-100 parts of methyl vinyl silicone rubber, 16-23 parts of fumed silica, 11-17 parts of precipitated white carbon black, 1.3-2.2 parts of octamethylcyclotetrasiloxane, 30-40 parts of diatomite, 2-3 parts of titanium dioxide, 1.5-2.5 parts of titanium dioxide, 0.13-0.25 part of ferric oxide, 0.3-1 part of peroxidized bi(2, 4-dicholorbenzoyl), 0.5-0.9 part of 2, 5-dimethyl-2, 5-bi(tertiary butyl peroxy) hexane, 0.0015-0.002 part of platinum flame retardant, 15-20 parts of aluminum hydroxide, 20-30 parts of magnesium hydrate, 1-1.5 parts of dioctahedron alkaline aluminum silicate and 0.4-0.7 part of trioctahedron alkaline aluminum silicate. The efficient flame retardant cable sheath material disclosed by the invention is free from pollution, excellent in flame retardant effect and good in high-temperature self-extinguishing effect, and has certain strength and supporting capacity after combustion.

Canvas for a canoe comprises gray fabric, an inner coating and an outer coating, wherein the gray fabric is filament woven plain cloth, the inner coating is prepared from, by weight, 25-35% of polyvinyl chloride paste resin, 10-30% of dioctyl phthalate, 10-20% of dioctyl adipate, 8-10% of polyester type plasticizer, 20-35% of light calcium carbonate, 2-5% of lead oxide phosphite hydrate, 1-3% of titanium dioxide, 0.1-1.5% of preservative, 0.5-3% of flame retardant and 1-2% of pigment, and the inner coating is 0.5-1 mm thick; the outer coating is a polypropylene calendering film and is prepared from, by weight, 60-70% of polypropylene resin, 0.3-0.8% of ultraviolet light absorber, 15-30% of flame retardant, 10-15% of glass fiber and 0.6-1% of pigment, and a polyamide film which is purchased from market and 0.2-0.4 mm thick can also be adopted. A method for preparing the canvas mainly comprises the steps of padding and sizing, plasticizing in an oven, surface flattening and cooling into coils.

The invention discloses a method for machining a round-section polytetrafluoroethylene filament by virtue of a cutting-hot melting shaping method. The method comprises the following steps: mixing polytetrafluoroethylene dispersion resin powder with a liquid lubricant, and carrying out processes including material mixing, blank pressing, calendaring, longitudinal drawing, cutting, hot melting shaping and the like, thereby machining the polytetrafluoroethylene filament. The method is simple and is low in cost; the section of the prepared polytetrafluoroethylene filament is approximately round, the strength of the polytetrafluoroethylene filament is 4.3-3.2 cN / dtex, and the damage to the filament in acupuncture and spunlace machining processes can be greatly reduced; the filament can be widely applied to high-temperature tail gas treatment in waste incineration treatment plants, coal-fired power plants, industries of cement and the like and has remarkable economic and social benefits.

The invention relates to a pure-natural pollution-free dry-mixed floor mortar, which is prepared from the following raw materials in parts by weight: 200 to 250 parts of cement, 710 to 750 parts of yellow sand, 40 to 70 parts of pulverized fuel ash, 0.5 to 2 parts of additive, and 20 to 30 parts of natural thickening agent, wherein the additive is hydroxypropyl methyl cellulose; the natural thickening agent is a mixture prepared from the raw materials in parts by weight: 20 to 30 parts of glutinous rice flour, 15 to 35 parts of egg white powder, 25 to 30 parts of clay soil powder and 15 to 30 parts of straw meal. The pure-natural pollution-free dry-mixed floor mortar has the advantages that the natural thickening agent is adopted, so that on one hand, the overall viscosity of the mortar added with water can be improved, and a series of problems of shrinkage crack, water seepage, sand strip, peeling deformation, low strength level and the like of a surface layer of a floor at the later stage are prevented; on the other hand, the mortar is pollution-free to a human body, and the problem that straw stalks cannot be utilized can be effectively solved; the materials can be effectively smashed through a rotary cutter disc, and a filter effect of a filter box is effectively improved through horizontally swinging the filter box in a reciprocating way.

The invention relates to a heat preservation wall slab for a rear wall of a greenhouse. The heat preservation wall slab adopts a 5-layer structure, wherein the middle layer is a center slab layer that is 5-10 mm in thickness; the two layers above and below the center slab layer are heat preservation layers that are 10-20 mm in thickness; and the two layers above and below the heat preservation layers are antiflaming layers that are 5-10 in thickness. The center slab layer is pressed at one time by using aluminum alloy, wood plastic, aluminum plastic and polyphenyl foam particles; each heat preservation layer is formed in such a manner that two plastic foam slabs are bound together by a binding material layer; and each antiflaming layer consists of magnesium chloride, magnesium oxide, expanded vermiculite, binding agent and emulsifier. The heat preservation wall slab for the rear wall of the greenhouse has the advantages that the manufacturing is simple, the wall is high in strength, the heat preservation effect is good, and the flame resistance is high.

The invention relates to a municipal drainage pipeline construction method, and relates to the technical field of municipal pipeline installation. The municipal drainage pipeline construction method includes the following steps of S1, surveying and setting out, S2, pile base positioning, S3, stirring pile formation, S4, repeated stirring and lifting, S5, trench excavation, S6, heel block laying, S7, drainage pipeline installation, S8, concrete cushion pouring, and S9, soil backfilling. Before trench excavation, mutually-engaged stirring piles are formed on the two sides of a trench, thus the stirring piles can reinforce and support the side walls of the trench and can prevent water on the outer side of the trench from permeating into the trench to affect drainage pipeline installation, sloping and support of the trench during trench excavation are avoided, and the occupied area during trench excavation is decreased.

The invention provides a compound type concrete foaming agent, a preparation method and an application thereof. The compound type concrete foaming agent is prepared by compounding a component A and acomponent B, wherein the component A comprises 10-20 parts of polyvinyl alcohol, 15-25 parts of colophony, 1.5-2.5 parts of anhydrous sodium carbonate, 3.5-4.5 parts of industrial sodium hydroxide, 3-5 parts of triethanolamine, 0.2-0.5 parts of industrial grade hydrochloric acid and 53.5-55.8 parts of water; and the component B comprises 0.2-0.5 parts of triethanolamine, 8-10 parts of sodium sulfate, 12-15 parts of sodium nitrite, 10-25 parts of calcium chloride and 54.7-64.5 parts of water. The compound type concrete foaming agent not only can increase the doped quantity of the foaming agentbut also can compensate the concrete strength and the solidification time; the compound type concrete foaming agent can be used for manufacturing foam concrete with super-low capacity, also utilize alarge amount of waste residues, such as industrial and architectural rubbish and the like, to produce light foamed concrete.

A prepared two-component quick-hardening early-strength liquid soil stabilizer is suitable for premixed flow-state solidified soil construction and comprises a curing agent component A and a curing agent component B. The curing agent component B is a liquid quick-hardening early-strength auxiliary agent, has a coagulation-promoting early-strength excitation effect and is used for preparing quick-hardening early-strength solidified soil. The stabilizer has the advantages of short setting time, high early strength, good fluidity, no need of whole-course paving, strong adaptability to foundationsoil and the like.

The invention discloses an ultra-light-weight composite environment-friendly fiber board and a preparing method of the ultra-light-weight composite environment-friendly fiber board, and belongs to the technical field of an ultra-light-weight fiber board. The ultra-light-weight composite environment-friendly fiber board is characterized by comprising an upper flame-retardant wood fiber layer, a lower flame-retardant wood fiber layer and a wood fiber and expanded perlite mixing layer arranged between the upper and lower flame-retardant wood fiber layers. The invention also discloses the preparing method of the ultra-light-weight composite environment-friendly fiber board. The ultra-light-weight composite environment-friendly fiber board has a series of advantages that the supporting capacity of a high-rise building partition wall is effectively reduced; the strength of the wall surface is enhanced; the properties such as the impact-resistant property, the folding-resistant property and the nail holding force are good; the heat insulation function, the fireproof function, the sound isolation function, the anti-seismic function and the aging-resistant effect are achieved; the secondary wall surface decoration is convenient; and the attaching force of a decoration surface is strong, and the like.

The invention discloses a pre-paved expansive self-enclosed particulate matter for a waterproof roll and a preparation method of the particulate matter. The particulate matter is prepared by the following steps: uniformly mixing sodium bentonite and a high water-absorbing polymer so as to obtain a mixture; and adhering and granulating the mixture with a polyvinyl alcohol aqueous solution, and coating by using an alkaline soluble polymer, rubber and an organic solvent, thereby obtaining the particulate matter. The particles in delayed high expansion are adopted after concrete grouting and curing; because materials in the cement can separate out the calcium hydroxide component, the cement is partially alkalized, and the coating material on the particle surface is swelling and permeable, so that the particles are rapidly expanded, the gap between the roll and the concrete is filled, waterproof colloid is formed, the lower surface of the concrete is completely enclosed, infiltration of underground water is avoided, and an effect of completely preventing water is achieved; and moreover, the waterproof roll is short in construction period and can remain a certain strength when meeting water, the performance of the material is guaranteed, and the problem that the basement pre-paved roll is complicated and difficult to seal is solved.

The invention provides a load bearing board and a degreasing technology of a zirconia ceramic injection molding blank and application thereof, and relates to the technical field of production and preparation of zirconia ceramic products. The load bearing board comprises a substrate. A load bearing platform used for placing the zirconia ceramic injection molding blank is arranged on the surface ofthe substrate. The load bearing platform protrudes from the surface of the substrate. By using the load bearing board, the problem that existing load bearing boards in the prior art are easy to causelarge deformation, cracking, insufficient glue discharge or unstable shrinkage of the injection molding blank during degreasing of the zirconia ceramic injection molding blank can be alleviated.

An insulated wire includes a conductor, a foundation layer covering the conductor, and an insulated layer formed on the foundation layer. The foundation layer is configured with a hardening body of a resin composition including a heat curing resin having an epoxy resin, and a reactive functional group. The heat curing resin includes 1 to 10 parts by mass with respect to 100 parts by mass of the epoxy resin. Further, the heat curing resin preferably includes 5 to 30 parts by moss of blocked isocyanate with respect to 100 parts by mass of the epoxy resin.

The invention provides fast qualitative filter paper. A three-layer structure is formed from the inflow surface to the outflow surface of the filter paper. A middle layer of the three-layer structure comprises, by weight, 20-40 pats of viscose and 30-80 parts of alkali treated cotton linter pulp. An inflow surface layer comprises, by weight, 10-30 parts of cellulose acetate fiber and 30-60 parts of linen fiber. An outflow surface layer comprises, by weight, 10-30 parts of polypropylene fiber and 40-80 parts of bamboo fiber. The fast qualitative filter paper has the advantages of being high in filtration absorption performance, long in service life, high in wet strength and high in compressive strength.

The invention provides a high-strength white porcelain glaze ceramic product and a preparation method thereof, the high-strength white porcelain glaze ceramic product comprises a body material and glaze, the body material comprises the following raw materials: kaolin, potassium feldspar, limestone, a fluxing agent, zircon and ceramic micropowder; and the glaze comprises the following raw materials: albite, limestone, montmorillonite, quartz, magnesium oxide, iron oxide, aluminum oxide, plant ash and zircon. The preparation method of the high-strength white porcelain glaze ceramic product comprises the following steps: 1, preparing raw materials; 2, performing biscuit firing of the green body; 3, preparing glaze water; and 4, glazing and firing. The ceramic product manufactured by adopting the raw materials and the manufacturing process provided by the invention is smooth and bright in color and luster, is milky white like congealed fat, shows pink or milky white in glaze under illumination, and has the characteristics of high glaze brightness, fine porcelain, firmness, durability, easiness in cleaning and difficulty in breaking.

The invention discloses a composite containing polyhydroxybutyrate copolymer and polylactic acid used for the foaming material. The composite contains polyhydroxybutyrate copolymer P (3HB-co-4HB), polylactic acid and foaming agent, has a certain tensile strength, elongation at break and expansion ratio, has thorough biological degradation and can be widely used in the packaging field.

The invention relates to a preparation method for a natural fiber-containing modified car trim. The preparation method includes the following steps: (1) preparation of materials; (2) preparation of biomass powder: Natural fiber-containing biomass is milled into powder by a ball mill, the powder is dried, and thereby biomass powder is obtained; (3) modification of biomass powder: The biomass powder prepared in step (2) is poured into a high-speed mixer, meanwhile, an additive and ore powder are added in, premixing is carried out, heating is carried out for drying, the heating temperature is 70 DEG C to 170 DEG C, the heating time is 10 to 15 minutes, and thereby modified biomass powder is obtained; (4) mixing and pelletization: The obtained modified biomass powder and polypropylene (PP) are mixed and pelletized in pelletization equipment, and the pelletization temperature is 165 DEG C to 250 DEG C; (5) injection molding: The obtained biomass-modified PP material and a PP injection-molding production material are mixed and added with an additive, injection molding and product preparation are carried out, and thereby the biomass-containing modified plastic car trim is obtained.

The present invention discloses an electrode materials of composite rare-earth iridium alloy that is a noble metal alloy containing Ir. The noble metal alloy contains 99.5-99.9 wt% Ir and 0.10-0.50 wt% X; the X is one or a mixture of some of the La, Nd, Pr, Y, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Ce; the noble metal alloy can also contains Th and Al added at the same time. The invention also discloses a sparking plug of composite rare-earth iridium alloy, includes a center electrode and at least a lateral electrode, ignition tip of the center electrode and / or the lateral electrode is the noble metal alloy. The invention provided electrode materials has advantage of high-temperature resistance, strong high-temperature corrosion resistance and excellent performance price ratio; sparking plug of using the electrode materials can provide strong spark on time even the motor is in high-speed, high-temperature high-pressure condition.

The invention provides medium-speed qualitative filter paper. The medium-speed qualitative filter paper is of a three-layer structure from an inflow face to an outflow face of the filter paper, wherein a middle layer of the three-layer structure contains the ingredients in parts by weight: 20-40 parts of softwood pulp and 30-80 parts of alkali-treated cotton linter pulp; the inflow face contains the ingredients in parts by weight: 10-30 parts of acetate fibers and 30-60 parts of flax fibers; the outflow face contains the ingredients in parts by weight: 10-30 parts of polypropylene fibers and 40-80 parts of bamboo fibers. The medium-speed qualitative filter paper has the characteristics of good filtering and absorbing performance, long service life, good wet strength and high compressive strength.

The invention discloses a handle type blade with three pressure sensing holes at the front edge of each element stage. The handle type blade comprises the pressure sensing holes, a pressure guiding channel, a handle, a pressure guiding pipe connector and a low-loss bent pipe. The front edge of the blade is provided with the multiple rows of pressure sensing holes in the blade height direction, each row comprises three pressure sensing holes which are respectively distributed at a front edge point of each element stage, a pressure surface and a suction surface; and the pressure guiding channelis respectively connected with orifices of the pressure sensing holes and the pressure guiding pipe connector, and the low-loss bent pipe is adopted at the bent part. According to the handle type blade, the total pressure, static pressure, deflection angle and Mach number of airflow at an outlet of a compressor rotor in the blade height direction and at the multiple element stage positions can besimultaneously measured, and the handle type blade is suitable for measuring the distribution of two-dimensional flow field parameters at the outlet of the rotor in the blade height direction. The handle type blade has the pneumatic performance and strength of a conventional blade, and importantly has the function of measuring the pneumatic parameters, and compared with a measurement technology ofa conventional probe and a blade type probe, the handle type blade has the advantages of no overhanging probe, no interference with a measured flow field structure, no influence on the pneumatic performance of the blade and high measurement parameter precision.

The invention provides an a luminum-zirconium-carbon sliding plate brick prepared by combining nickel-aluminum alloy-containing organic silicon resin with high-temperature firing. The aluminum-zirconium-carbon sliding plate brick is prepared from the following raw materials in percentage by weight: 50 to 65 percent of corundum, 15 to 30 percent of fused zirconia corundum, 6 to 12 percent of activated aluminum oxide micropowder, 1 to 3 percent of monoclinic zirconium oxide, 1 to 2 percent of metal silicon micropowder, 1 to 3 percent of carbon black, 1 to 2 percent of carbon-containing resin powder and 0.5 to 1 percent of boron carbide. The aluminum-zirconium-carbon sliding plate brick further comprises organic silicon resin accounting for 3-4% of the total amount of the above raw materials and nickel-aluminum alloy powder accounting for 0.2-1% of the total amount of the above raw materials. According to the invention, a nickel-aluminum alloy raw material is introduced, in-situ fibrous nanocarbon is generated between aggregate and a matrix in a high-temperature firing process under the catalytic action of nickel, the bonding strength and toughness between the aggregate and the matrix are improved, and then the thermal shock resistance and other performance of the material are improved; and the prepared aluminum-zirconium-carbon sliding plate brick has the advantages of long service life, stable performance and the like.

The invention relates to a wear-resistant and erosion-resistant rubber liner plate with a layer structure and a preparation method of the rubber liner plate and belongs to rubber materials in the field of polymer materials. The rubber liner plate is formed by hot curing adhesion of a rubber substrate and surface wear-resistant rubber, wherein the surface wear-resistant rubber uses aramid fiber glass fiber and chinlon fiber to constitute a framework, special corrosion-resistant rubber is taken as a base material, and silicon carbide micropowder or zirconium carbide micropowder, aluminum oxide micropowder, silicon oxide micropowder and elemental silicon micropowder are added as admixtures for preparation, so that when the rubber liner plate is applied as a lining material, the rubber liner plate integrates not only certain strength, wear resistance, erosion resistance and puncture resistance, but also certain resilience and flexibility; and compared with a conventional metal liner or a liner poured by an inorganic nonmetallic material, the rubber liner plate has the characteristics of light weight and easiness in mounting and replacement.

The invention provides rapid quantitative filter paper. The rapid quantitative filter paper is of a three-layered structure from a flowing-in surface to a flowing-out surface of the filter paper; a middle layer of the three-layered structure is prepared from the following raw materials in parts by weight: 20 to 40 parts of softwood pulp and 20 to 40 parts of hardwood pulp; the flowing-in surface layer is prepared from the following raw materials in parts by weight: 20 to 40 parts of softwood pulp and 30 to 80 parts of short-staple cotton pulp; the flowing-out surface layer is prepared from the following raw materials in parts by weight: 20 to 40 parts of hardwood pulp and 30 to 80 parts of short-staple cotton pulp; the softwood pulp, the hardwood pulp and the short-staple cotton pulp are immersed with a mixed solution of hydrofluoric acid and hydrochloric acid respectively, then are neutralized with an alkali and are finally washed with ion-exchanged pure water or distilled water to prepare the rapid quantitative filter paper. The rapid quantitative filter paper has the characteristics of good filtering and absorption performances, long service life, good humidity and strength and high compressive strength.