142results about How to "Not easy to float" patented technology

The invention discloses a self-propelled inverted arch template construction method for a tunnel, which comprises the following construction steps of: setting out a control line for an inverted arch digging section and a longitudinal construction joint according to the design requirement; performing smooth-wall blasting digging on an inverted arch of the tunnel; moving an inverted arch trestle in place; conveying inverted arch stone slag out of the tunnel by using an excavator and a conveying device and abandoning the stone slag in a slag field, and cleaning an inverted arch base; assembling an inverted arch end template; laying steel rails, and moving the inverted arch template to longitudinally move in place per se; starting a hydraulic device to lower the inverted arch template, and supporting the template firmly by using a screw jack; pouring inverted arch concrete; and curing the concrete with equal strength, folding the screw jack, withdrawing a hydraulic cylinder, and releasing a die. The construction method has low cost, is convenient to operate, and improves the construction efficiency; and the longitudinal construction joint is vibrated densely compared with common template construction, and has positive effect of improving the construction quality of tunnel engineering.

The invention discloses a lightweight aggregate high-performance concrete and a preparation method thereof. The lightweight aggregate high-performance concrete contains the following raw materials: 180-310 parts of cement, 580-650 parts of ceramsite, 420-500 parts of pottery sand, 0-80 parts of sand regenerated from construction waste, 100-130 parts of coal ash, 100-210 parts of mineral powder, 130-160 parts of water, 4.5-6.5 parts of water reducer, 1-1.5 parts of enhanced modified material and 0.45-0.60 part of anti-separation material. The lightweight aggregate high-performance concrete has the advantages of light unit weight (1450-1550kg / m3), high 28-day strength (40-50MPa), separation resistance, capability of being pumped, slump of 190-250mm, divergence of 400-550mm, no aggregate floating, simple preparation method, high operability and low cost.

Relating to sewage treatment devices and sewage treatment methods, the invention provides an integrated sewage treatment device of a membrane bioreactor and a sewage treatment method. The invention aims to solve the problems of large land occupation area, high operation cost, complex operation management, unstable effluent quality and the like in existing sewage treatment technologies and devices. In the invention, a three-phase separator component is arranged inside a membrane bioreactor, and by means of bottom aeration and the separation effect of the separator, an integrated device with ananoxic upper part and an aerobic lower part can be formed. Sewage enters from the upper anoxic area of the reactor, and then enters the lower aerobic area through a slit of the three-phase separator.Meanwhile, a mixed solution backflow device is disposed to return a mixed solution in the aerobic area to the anoxic area, thus finishing nitrogen removal treatment of the sewage. The sewage treatment device and method provided in the invention can realize synchronous nitrogen removal and decarbonization, and have the advantages of small land occupation area, saving of sewage treatment required alkalinity and engineering cost, as well as simple operation management. And the sewage treatment device and method of the invention can be applied in treatment of urban sewage or nitrogen-containing industrial wastewater.

The invention relates to an anaerobic ammoxidation sludge embedding immobilization method belonging to the field of sewage treatment, and particularly provides a method for performing embedding immobilization on anaerobic ammoxidation sludge by adding magnetic powder and powdered activated carbon. The method comprises the following steps: preparing an embedding agent, mixing anaerobic ammoxidation sludge with the embedding agent, preparing immobilized anaerobic ammoxidation balls, activating the immobilized anaerobic ammoxidation balls and the like. The preparation of the embedding agent comprises the following steps: weighing polyvinyl alcohol (PVA), sodium alginate (SA), powdered activated carbon and magnetic powder, and preparing into a solution, wherein on the basis of percentage in mass, the concentration of the PVA is 6-10wt%, the concentration of the SA is 2-3wt%, the concentration of the powdered activated carbon is 1-2wt%, and the concentration of the magnetic powder is 2-4wt%; and uniformly stirring, thus preparing the mixed embedding agent. The method is simple in preparation process, easy to operate and low in preparation cost; and the prepared embedding immobilization anaerobic ammoxidation balls are high in activity, favorable in stability and suitable for industrial production, and can achieve favorable economic and environmental benefits.

The invention discloses a method for inhibiting release of substrate sludge nutritive salt of a eutrophic water body, which belongs to the field of controlling substrate sludge pollution. Ferric salt passivating agent, magnesium salt or magnesium hydroxide emulsion, calcium nitrate and flocculating agent are injected into the substrate sludge within 10 centimeters away from the surface layer according to the following amount respectively. The invention further adopts the technical scheme that the method comprises the following steps: extracting the substrate sludge within about 10 centimeters away from the surface layer into a container, stirring the substrate sludge during injecting the passivating agent into the substrate sludge, and spraying the substrate sludge added with the passivating agent to the extracted substrate sludge surface layer. The release amount of ammonia nitrogen in the substrate sludge to the water body is reduced by 60 to 80 percent, the release amount of total P is reduced by 70 to 85 percent, the water stable aggregates reach over 80 percent, and the passivating agent is stable and is not easy to float. By using substrate sludge extracting mixed method, the passivating agent and the substrate sludge can be fully mixed, the treatment cost is low, and large-scale application is easy to realize. The method can be applied to nutritive salt passivating treatment of the substrate sludge of the non-drinking water bodies of seriously polluted lake regions, black and smelly rivers, landscapes and the like.

The invention discloses an air flow drying oven for drying the coating of a radiate material and a blast nozzle part thereof. The blast nozzle part is a case, the lower part of which is provided with an air inlet. The middle of the upper part of the case is provided with a guide roller groove, and the case is provided with an inner cavity at the lower part and a left air duct and a right air duct which are positioned at the left side and the right side of the upper part and directly communicated with the inner cavity. An air outlet of the left air duct is a left parallel air flow blast nozzle which inclines towards the left, and the air outlet of the right air duct is a right parallel air flow blast nozzle which inclines towards the right. When the blast nozzle part is used in the drying oven, the left and right blast nozzles accelerate the flow flowing to the left and right sides of the blast nozzle part, and a left horizontal supporting plate and a right horizontal supporting plate lead the air flow to form parallel wind which is parallel to the radiate material, thus increasing the direct contact area between the wind and the radiate material, leading the radiate material surface to be heated evenly and the heat exchange between the parallel hot wind and the radiate material to be more sufficient, improving the heat exchange efficiency and having better drying quality due to even heating.

The invention discloses high pumping LC15 ceramsite concrete and a preparation method thereof. The high pumping LC15 ceramsite concrete comprises the following components: cement, sand, ceramsite, mixing water, fly ash, an additive, ore slag powder, a pumping agent and aqueous polyurethane emulsion; the additive is a polycarboxylate superplasticizer, and the pumping agent is compounded by the following components: modified starch ether, polyacrylamide, sodium carboxymethyl cellulose, a retarder, epoxy resin and water. The high pumping LC15 ceramsite concrete enables the ceramsite to fully absorb water, and then through the aqueous polyurethane emulsion and the pumping agent, the bonding of the ceramsite with cementing materials such as the cement, the fly ash and the like is promoted, thecohesiveness and water retention of the ceramsite concrete are increased, and the ceramsite is not easy to float up, delaminate and segregate; and the aqueous polyurethane emulsion is used to adhere an inorganic heat preservation modifier to the ceramsite, and the weight of the ceramsite is increased, so that the ceramsite is not easy to float up, delaminate and segregate, and the heat preservation performance of the ceramsite concrete is improved.

The invention discloses a preparation method for yogurt lump. The method comprises the steps of fermenting, acidization, curdling, whey discharging, water washing, storing, forming, sealing, after-ripening and packaging by adopting special lactic acid bacteria to inoculate milk or goat milk which is standardized and pasteurized. The invention can not only lead the traditional yogurt lump product to be safer and more sanitary with stable quality, subtle taste and modest hardness. And since the step of the after-ripening is controlled appropriately, the prepared yogurt lump is of fuller flavor with little cream precipitated, high yielding rate and can meet popular taste and be used for producing yogurt lump with different water content, tastes and textural quality, which has more market competitiveness and can greatly enrich the processing technology and flavor of traditional yogurt lump.

The invention discloses a technological method of employing foamed ceramics for auxiliary production of foamed aluminum. The method includes: making foamed ceramic particles with certain size, density and porosity, at the same time mixing the foamed ceramic particles with TiH2 foaming agent powder for foamed aluminum, and letting the powder fully integrate into the pores of the foamed ceramics. In the production process of foamed aluminum, the ceramic particles stuck with foaming agent powder and the foaming agent powder are added into an aluminum solution simultaneously to better improve the foaming process. The method proposed by the invention utilizes the characteristics of high strength and high melting point of foamed ceramics serving as the additive, and improves the mechanical properties of the foamed aluminum material itself. At the same time, the foaming agent in the foam ceramic particles relies on the ceramic particles to produce gas outward, the ceramic particles have rough outsides and also have certain gravity in it-self, thus being difficult to float and driving small air bubbles around not easy to float. The method provided by the invention solves the problem of uneven porosity caused by bubble floating in traditional processes of producing foamed aluminum by melt foaming.

The invention discloses a device and a method for processing C / N urban household wastewater by an A2O-BAF (Biological Aerated Filter) process. The device comprises a water inlet tank, an A2O reactor, a secondary sedimentation tank, an intermediate water tank, a BAF reactor and a water outlet tank connected in sequence. Raw water and return sludge are pumped from the water inlet tank to an anaerobic zone; mixed liquor in the anaerobic zone and nitration liquor enter in the anaerobic zone; the mixed liquor in the anaerobic zone then enters in an aerobic zone; mixed liquor from the A2O enters in the intermediate water tank; supernate is pumped from the intermediate water tank to the BAF; sludge in the secondary sedimentation tank reflows to the anaerobic zone; the separated supernate enters in the BAF in which effluents water enters in the water outlet tank; and part of water in the water outlet tank reflows to an anoxic zone and the other part is discharged. The invention reduces the aeration amount, saves carbon sources, effectively improves the nitration and prolongs the backwashing time of the BAF.

The invention discloses a swimming pool water treatment system. The swimming pool water treatment system comprises a swimming pool, a balance pool, a hair collector, a circulating pump, a high-efficiency filter, a lifting pump, an ozone generator, an ozone reaction tank, an active carbon adsorption tank, heat exchange equipment and a chemical dosing device, which are connected in sequence, wherein the heat exchange equipment is connected with the swimming pool; the swimming pool water treatment system further comprises a cosmetic treatment device, a urea treatment device and a photocatalytic sterilization device which are connected between the active carbon adsorption tank and the heat exchange equipment. According to the swimming pool water treatment system disclosed by the invention, hairs in swimming pool water are filtered through the hair collector; the high-efficiency filter is used for filtering particle impurities in the swimming pool water; the cosmetic treatment device is used for treating components including glycerol, alcohol and the like in the swimming pool water; the urea treatment device is used for adsorbing urea in the swimming pool water; the photocatalytic sterilization device is used for decomposing bacteria and microorganisms in the swimming pool water; finally, the water body quality of the swimming pool water is improved.

The invention provides an intelligent new textile material cutting device for spinning, belongs to the technical field of textile cutting devices, and aims to solve the problem that when a new textilematerial is cut by the cutting device, the middle of the new textile material is still wrinkled during cutting, so that the cutting quality of the cutting device during cutting is reduced. The cutting device comprises a base; a C-shaped support is fixedly connected to the middle of the upper end face of the base; and a lifting mechanism is arranged at the top of the inner side of the C-shaped support. Through the arrangement of pressing mechanisms, in the cutting process, when a circular cutting blade makes contact with the new textile material, and pressing belts on the two pressing mechanisms make close contact with the upper surface of the new textile material, so that a cutting area of the new textile material is effectively pressed; and when the circular cutting blade moves leftwardsand rightwards, the pressing belts can be driven on the peripheral surfaces of pressing rollers, so that the new textile material cannot be wrinkled during cutting, and the cutting quality of the cutting device during cutting is improved.

The invention discloses a preparing method of a novel reinforced bar type ultra-high-performance concrete pipeline. An adopted pipeline forming mold comprises a steel outer mold and an inner mold. The method comprises the following steps that (1) a steel bar framework is welded, a longitudinal bar of the framework is unchanged, and an annular bar is processed into an oval shape; (2) the mold is assembled, a steel bar framework is fixed, a pumping machine is connected with the mold, and the sealing performance is checked; (3) an ultra-high-performance concrete mixture is prepared; (4) the ultra-high-performance concrete mixture is added into the pumping machine, and a pumping jacking process is adopted for forming a pipeline; (5) after the pumping is completed, a closed grouting opening of the mold is sealed in time; (6) a pipeline with the mold is subjected to integral maintenance; (7) the mold is dismounted; (8) hydrothermal maintenance or natural maintenance is carried out after the pipeline mold dismounting. The invention also discloses the novel reinforced bar type ultra-high-performance concrete pipeline. The pipeline annular bar prepared by the method provided by the invention is in an oval shape, so that the strength of a reinforced bar is effectively utilized, and the pipeline strength is improved.

The invention discloses a dam with pile groups and a permeable frame and a construction method of the dam. The construction method includes: piling vertical dam piles in a to-be-constructed river, arranging a mesh between each two adjacent vertical dam piles so that the vertical dam piles and the meshes form a closed block, casting the permeable frame in the mashes to form a permeable frame unit, and casting other permeable frames into the meshes so that the permeable frame units form the dam with the pile groups and the permeable frames. The dam has the advantages of stability in structure, long engineering life cycle, eco-environment protection, convenience in construction and the like.

A micron / nanometer metallurgical addition agent is prepared as the following steps: evenly mixing micron powder, nano powder and metal powder by ball milling, wherein the metal powder serves as an adhesive and is briquetted, the weight ratio of the metal powder and micron powder to nano powder is (4-10):1, and the micron powder and nano powder utilize metal oxides such as Al2O3 powder, ZrO2 powder, CaCO3 powder, CaO powder and the like, or metal nitrides such as TiN powder, AlN powder and the like, or metal powder carbides such as WC powder, SiC powder and the like, or metal power such as Ca powder, Al powder, Mg powder and the like or alloy powder, or micro / nano carbon powder, fiber powder, etc. The metal powder serving as the adhesive comprises components which are the same as or similar to the components of a product matrix, does not pollute melt and only plays a carrier role. The addition agent is rushed into melt by high temperature melt and is evenly dispersed by the impact and stirring functions of the melt, and the addition agent also can be added in the melt by an injection method or an insertion method.

The invention provides a flexible circuit board and a liquid crystal display applying the same. The flexible circuit board comprises a main body circuit board, a light bar circuit board and a connecting circuit board. The light bar circuit board comprises a plurality of light-emitting elements. The connecting circuit board is connected with the main body circuit board and the light bar circuit board. The connecting circuit board comprises a plurality of penetrating holes, and vertical projection of each light-emitting element at the connecting position of the connecting circuit board and the light bar circuit board is overlapped with at least a part of vertical projection of at least one penetrating hole at the connecting position of the connecting circuit board and the light bar circuit board. By adopting the flexible circuit board and the liquid crystal display, the penetrating holes are arranged on the connecting circuit board to decrease elastic force produced by the flexible circuit board in bending. Furthermore, due to the fact that positions of the penetrating holes correspond to the positions of the light-emitting elements, the elastic force of a part of connecting circuit board corresponding to the light-emitting elements is not smaller than that produced by other portions even if the flexible circuit board produces the elastic force, and the light-emitting elements do not easily float from the liquid crystal display.

A double-sided adhesive sheet (1) is provided with: an adhesive laminated body, that is provided with a base material (20), a first adhesive layer (21) laminated on one surface of the base material (20), and a second adhesive layer (22) laminated on the other surface of the base material (1); a first peeling sheet (31) laminated on the first adhesive layer (21) surface on the reverse side of the base material (20); and a second peeling sheet (32) laminated on the second adhesive layer (21) surface on the reverse side of the base material (20). In the double-sided adhesive sheet (1), the thickness of the base material (20) is 1-5 Mum, the thicknesses of the first adhesive layer (21) and the second adhesive layer (22) are 1-5 Mum, respectively, peeling forces of the first peeling sheet (31) and the second peeling sheet (32) are 10-30 mN / 25 mm, respectively, and a difference between the peeling force of the first peeling sheet (31) and the peeling force of the second peeling sheet (32) is equal to or less than 5 mN / 25 mm.

The invention relates to a rubber asphalt, preparation and application thereof. The preparation method includes: mixing rubber powder, a stabilizer and an assistant at 20-100DEG C; extruding and devolatilizing the mixture by an extruder for reclaimed rubber desulfurization production at 180-250DEG C, making the extruded devolatilized material into desulfurized devolatilized particles by die surface grain cutting equipment; adding the mixture of the desulfurized devolatilized particles and a crosslinking agent into asphalt, and conducting shearing at 120-160DEG C for 10-30min. The weight ratio of the asphalt / desulfurized devolatilized particles is 70-80:30-20; the stabilizer is a copolymerized elastomer of ethylene and alpha olefin, and accounts for 10-30% of the weight of the rubber powder. The assistant is furfural extract oil, and accounts for 3-20% of the weight of the rubber powder. The crosslinking agent is sulfur, and accounts for 0.2-5% of the desulfurized devolatilized particles. The rubber asphalt has the characteristics of environment-friendly processing process, high temperature storage stability and high elastic recovery, and can be used for stress absorbing layers, asphalt mixtures, waterproof bonding layers and caulking materials.

The invention discloses a metalized safety film layer stacked-type pulse capacitor, and the capacitor comprises a capacitor packet, a leading-out soldering lug, a plastic housing, and filling resin. The capacitor packet is disposed in the plastic housing, and the interior of the plastic housing is provided with the filling resin. One end of the leading-out soldering lug is connected with the capacitor packet, and the other end of the leading-out soldering lug is located outside the housing. The capacitor also comprises plastic glue for fixing the capacitor packet in the plastic housing. The capacitor packet is formed by the stacking of a metalized film, and the metalized film comprises a central film substrate, a first metal coating layer, a second metal coating layer, and a laminated film medium. The first and second metal coating layers respectively comprise a plurality of square blocks, and the positions of the square blocks of the first and second metal coating layers are corresponding to each other. The capacitor can reduce the size and increase the capacity, is stable at a large-current state, is not liable to be damaged by arcing and breakdown.

The invention discloses high-water-loss plugging agent solid-phase plugging particles for a drilling fluid. The high-water-loss plugging agent solid-phase plugging particles are prepared from the following raw materials in parts by weight: 50-60 parts of bisphenol A epoxy resin, 10-20 parts of an auxiliary agent, 50-60 parts of a fiber material and 16-20 parts of a curing agent; a fiber material is added in the preparation process, so that the strength, the hardness, the fullness and the stability of the solid-phase plugging particles are enhanced; the fiber material is small in size and can be used for filling gaps in the solid-phase plugging particles, so that the solid-phase plugging particles become more compact and are not easy to deform due to change of external conditions. An auxiliary agent is also added in the preparation process; azo diamide and sodium bicarbonate in the auxiliary agent have a foaming effect, so that a microporous structure is formed in the generated solid-phase plugging particles, the drilling fluid can quickly lose water on the plug surface, the influence caused by overlarge pressure due to quick water loss is reduced, and meanwhile, small-particle-sizeparticles can be effectively blocked.

The invention discloses an ecological sinking bed for deep polluted river treatment and in-situ remediation and a method thereof, and belongs to the field of environmental protection devices. The ecological sinking bed comprises a frame body, and the frame body is divided into plant planting areas located on the two sides and a filling area located in the middle. The plant planting area is used for planting aquatic plants, and the filling area is sequentially filled with zeolite, a solidified microorganism filler and a three-dimensional elastic filler from bottom to top in a layered mode. Theecological sinking bed is characterized in that the water body is purified in multiple modes by combining the physical adsorption and microbial degradation effects of the filler and the zeolite surface and the purification function of plants such as reeds, and a knife edge is designed for cutting the reeds, so that the problems of unfavorable conditions of easy damage, short tolerance time and thelike of floating beds due to large rain water flow speed and sun exposure and difficult recovery caused by rooting of the reeds are solved. The ecological settling bed is nontoxic and harmless in material, is not easy to damage, is durable, is convenient to recycle and reuse after finishing, and does not generate secondary pollution.

The invention discloses a hydrophobic water guiding device for foundation pit construction, and relates to the technical field of foundation pit construction. According to the technical scheme, the hydrophobic water guiding device is characterized by comprising drainage ditches, water collecting wells, a water pumping pump and water pumping pipes, the drainage ditches are arranged at the bottom ofa foundation pit, protective walls are arranged on the well wall of each water collecting well, a water filtering layer is arranged at the bottom of each water collecting well, the water pumping pipeare connected with the water pumping pump and stretch into the water collecting wells, and each filtering device comprises a box body and a filtering part; and the top of each box body is provided with a connecting hole for extending into the corresponding water pumping pipe, the side walls are provided with a large amount of water entering holes for supplying water to the interior, and the filtering parts are arranged inside the box bodies and sleeves the outer sides of the water pumping pipes. The water flows into the water collecting wells along the drainage ditches and flows into the boxbodies, sediment is removed through the filtering parts, and the water is extracted from the water pumping pipes. After the sediment is blocked by the filtering parts, the sediment naturally drops tothe bottoms of the box bodies, and does not accumulate on the surface of an outer ring net, so that the hydrophobic water guiding efficiency is ensured.

The invention discloses a method for increasing a sulfur-gold recovery rate in tailings of an old tailing pond. The method comprises the following steps: preparing flotation pulp, inflating and stirring in an oxidation and reduction system, floating sulfur-gold ores and the like. According to the method disclosed by the invention, an ore pulp preparation method adopting a wetting and soaking mode is adopted, so that poor flotation effect due to the fact that a sample and water are not mixed uniformly is avoided; by adopting an inflating and strong-stirring method of the oxidation and reduction system, so that surfaces of ores are reduced in the oxidation and reduction system formed after sodium sulfide inflation; and by virtue of strong stirring, ore grains scrub with one another to expose fresh surfaces of sulfur-gold ores, so that the problem that the sulfur-gold recovery rate in tailings of the old tailing pond is low due to the fact that the sulfur-gold ores are not liable to float in a direct flotation or activation flotation method is effectively solved, and therefore, the recovery rate for sulfur-gold in tailings of the old tailing pond is greatly increased, reagent cost is reduced and resources are saved.

The invention belongs to the field of building materials, and concretely relates to a high-strength lightweight aggregate concrete based on an arch shell-shaped interface region and a preparation method thereof. The high-strength lightweight aggregate concrete is prepared from the components: 400 to 500 kg / m<3> of cement, 40 to 80 kg / m<3> of pulverized fuel ash, 10 to 60 kg / m<3> of silica fume, 520 to 640 kg / m<3> of lightweight aggregate, 600 to 800 kg / m<3> of river sand, 6 to 8 kg / m<3> of high-efficient water reducer, 0.2 to 0.3 kg / m<3> of tackifier, 18 to 24 g / m<3> of air entraining agent, and 140 to 170 kg / m<3> of water. The high-strength lightweight aggregate concrete provided by the invention mainly adopts a spheroidal lightweight aggregate as an aggregate, and an internal curing effect and an arch shell interface effect of a prewet spheroidal lightweight aggregate are utilized, so that the lightweight aggregate concrete has performances of light weight, high strength, impermeability and corrosion resistance, the workability of the high-strength lightweight aggregate concrete is better, the lightweight aggregate is not easy to float upwards, and the concrete is high in strength, good in endurance quality and not easy to crack.

The invention relates to the technical field of existing building anti-floating, and discloses an existing building anti-floating system based on embedded self-propelled anchor rods and a construction method thereof. The existing building anti-floating system comprises an anchor rod group applied to an existing building anti-floating bottom plate, the anchor rod group comprises a plurality of self-propelled anti-floating anchor rods applied at 40-75 degrees, the self-propelled anti-floating anchor rods in the anchor rod group are oppositely arranged in a matrix mode, design requirements can be greatly met, horizontal disturbance can be resisted, and the displacement of the building in the horizontal direction is reduced; meanwhile, an anti-floating treatment mode of combining the self-propelled anti-floating anchor rods and a pressure relief device is adopted, so that the anti-floating plate can be effectively reinforced, the damaged part of the anti-floating plate can be effectively recovered, and cavities and gaps below the anti-floating plate can be effectively filled; and when the distribution density of the self-propelled anti-floating anchor rods is designed, the pressure relief effect of the pressure relief device is fully considered, so that the use amount of the self-propelled anti-floating anchor rods can be reduced while the floating problem of the existing building is effectively solved.

The invention provides a wax-free polishing method for an ultrathin semiconductor wafer, which comprises the following steps: (1) a gallium arsenide wafer to be polished with the diameter of D is placed on an adsorption pad mold A to be subjected to back rough polishing; the adsorption pad mold A is provided with a round hole A; the depth of the round hole A is 150-180 mu m; (2) the workpiece is placed on an adsorption pad mold B for front rough polishing; a round hole B is formed in an adsorption pad mold B; the depth of the round hole B ranges from 120 micrometers to 150 micrometers; (3) the gallium arsenide wafer processed in the step (2) is placed on an adsorption pad mold C to be subjected to back face fine polishing; the adsorption pad mold C is provided with a round hole C; the depth of the round hole C ranges from 80 micrometers to 120 micrometers; (4) placing the gallium arsenide wafer treated in the step (3) on the adsorption pad mold C for front fine polishing; and (5) washing. The wax-free polishing method for the ultrathin semiconductor wafer has the advantages that the breakage rate is lower; the percent of pass of the wax-free polishing double-polishing ultrathin gallium arsenide wafer processing technology is increased; and the production cost is reduced.

The invention relates to a copper-separating process of high-sulfur copper ore containing higher silicate minerals of speckstone and the like. The process comprises the following steps of: using solvent naphtha No. 200 and aerofloat sodium as a collector, oil No. 2 as a foaming agent and sodium sulfite as an inhibitor; carrying out bulk floatation on chalcopyrite and easily-floating silicate minerals; adding aluminum sulfate and ferrous sulfate for inhibiting the obtained copper-silicon mixed concentrate ; and re-separating and recovering the chalcopyrite by using a shaker. By the provided copper-separating process, copper ore in ore can be effectively recovered, the easily-floating silicate minerals are floated in the copper-separating process, and the influence of the silicate minerals of speckstone and the like on the subsequent floatation and recovery of sulfurous iron ore is eliminated.

The invention discloses a modular artificial fish spawning nest system and an installation method thereof, and belongs to the technical field of aquatic resource restoration. The upper portion of thefish spawning nest system is provided with a sinker and an egg sticky matrix A, the lower portion of the fish spawning nest system is provided with a floater and an egg sticky matrix B, and the fish spawning nest system comprises a plurality of fish spawning nests connected detachably. A bundle of Myriophyllum spicatum L., a bundle of hornwort, a bundle of potamogeton cristatus, a bundle of club moss or a bundle of Schoenoplectus wallichii are bound and fixed on the top of the fish spawning nest system, so that fishes with sticky eggs can lay eggs and breed, and a habitat is provided for growth of juvenile fishes. Polyethylene fiber wire balls are bound and fixed on the bottom of the fish spawning nest system, so that fishes with sticky eggs can lay eggs and breed, and a habitat is provided for growth of juvenile fishes, and the polyethylene fiber wire balls can be repeatedly used. The egg sticky matrix A and the egg sticky matrix B are fixed on the fish spawning nests, and are not easy to float greatly, so that fish eggs can be attached to the egg sticky matrix A or the egg sticky matrix B.