477results about How to "Lower working temperature" patented technology

The invention discloses a fast manufacturing method of three-beam laser compound scanning. The method comprises the following steps of: firstly utilizing long-wavelength laser (CO2 laser) for preheating the metal powder, then utilizing short-wavelength laser (YAG or optical fiber laser) for fusing the metal powder and finally utilizing long-wavelength laser (CO2 laser) to carry out heat treatment to the frozen metal. The fast manufacturing method uses the three beams of laser to carry out compound scanning, namely uses long-wavelength laser to preheat, short-wavelength laser to fuse and then long-wavelength laser to carry out heat treatment, can realize the compound process of preheating, fusion and heat treatment of the metal powder. The three beams of laser compound scanning mode can reduce internal stress of the metal part, avoid warping and cracking, improve organization and improve performance.

The invention discloses handheld cleaning equipment. The handheld cleaning equipment comprises an outer casing, a suction pipeline, a separation device, a dust cylinder, a power source, a filtering device, an airflow generator, a motor, an air outlet, a handle and a switch; the rear end of the outer casing is provided with the handle; the center at the front end of the outer casing is provided with the suction pipeline; the separation device is arranged behind the suction pipeline; the dust cylinder is arranged below the separation device; the filtering device is arranged above the separation device; the rear end of the filtering device is provided with the airflow generator; the rear end of the airflow generator is provided with the motor coaxially; the rear end of the motor is provided with the air outlet; the power source is arranged between the handle and the dust cylinder; the handle is provided with the switch. The handheld cleaning equipment has the advantages of being high in reliability, compact in structure, small and exquisite in size, strong in suction, good in filtering performance, low in working temperature, light in weight and convenient to use and having a wide market prospect in a dust collector market.

The invention discloses a printed circuit board embedded runner liquid cooling heat exchange device. The heat exchange device comprises a top PCB layer, a middle PCB layer and a bottom PCB layer, wherein a runner is laid on the middle PCB layer, and an embedded runner is formed after the runner is sealed by the top PCB layer and the bottom PCB layer. An inlet and an outlet of the runner are formed in the top PCB layer or the bottom PCB layer simultaneously, or positioned in the top PCB layer and the bottom PCB layer respectively. A plurality of metal conduction holes are formed in the top PCB layer or the bottom PCB layer provided with a heating device, the metal conduction holes are positioned under the installation position of the heating device and filled with a conductive material, and the conductive material is a good conductor of heat simultaneously. The printed circuit board embedded runner liquid cooling heat exchange device disclosed by the invention is capable of effectively solving the problem of heat dissipation of a high-power device in a printed circuit board, and is smaller in volume and higher in integration and reliability.

The invention belongs to the field of metal surface treatment, relating to a zinc phosphating solution of aluminium and aluminium alloy. The invention is mainly used for zinc phosphating treatment of the aluminium and aluminium alloy in the industries of home appliances, automobiles, hardware, building materials and railway locomotives. The zinc phosphating solution is composed of 8-25g/l of PO4<-3>, 6-16g/l of NO3<-1>, 1.6-8.0g/l of Zn<+2>, 0.12-0.38g/l of F<-1>, 0.6-8.0g/l of Fe<+2>, 0.01-1.5g/l of Ni<+2>, 0.0002-0.0006g/l of accelerating agent, 0.001-1.2g/l of organic complexing agent and the balance of water. When the phosphating solution of the invention is used for processing the aluminium and aluminium alloy, the obtained phosphating film has favourable matching capability with the coating, and the griding test of the paint film can reach 0 grade. The phosphating solution of the invention does not use toxic chromium, and the phosphating film does not contain chromium so as to solve the problems of environment pollution and toxic hazard on the human body when the chromium is used for processing the aluminium and aluminium alloy, and lower treatment cost.

The invention relates to the field of semiconductor electronic materials, and in particular relates to a silver nanowire doped conductive silver colloid and a preparation method thereof. The raw materials of the silver nanowire doped conductive silver colloid provided by the invention comprise the following components in percentage by weight: 25-60% of micrometer silver powder, 5-30% of silver nanowires, 20-50% of epoxy resin, 1.6-4% of curing agent, 5.8-9.2% of dissolvent, 0.4-1.6% of accelerant, 0.04-0.16% of toughening agent and 0.8-2.4% of additive. The conductive silver colloid is prepared by mixing and doping single-crystal silver nanowires and silver granules, thus, the total silver doping amount is reduced to 35-45%, and the conductive silver colloid has a favorable conductive effect, high shear strength, low working temperature and good ageing-resistant performance, and the cost of the conductive silver colloid is reduced. The silver nanowire doped conductive silver colloid can be widely applied to the fields of solar cell (film, crystal silicon) conductive colloids, conductive colloid LED (Light-Emitting Diode) package and the like.

The invention discloses a variable-gradient fractal lattice sandwiched reinforcement phase change heat sink and aims to provide an efficient phase change heat sink which is high in heat exchange efficiency, has certain universality and can be developed in a serialization mode. The variable-gradient fractal lattice sandwiched reinforcement phase change heat sink is realized according to the following technical scheme: reinforcement heat transfer structures are distributed in a phase change heat sink shell in an array; each variable-gradient fractal lattice sandwiched unit takes a variable-gradient V structure as a first-stage reinforcement heat transfer structure (4) according to the heat transfer and heat exchange characteristics of the phase change heat sink; on this basis, at variable-gradient V-shaped ends of the first-stage reinforcement heat transfer structures, the variable-gradient V structures in the same shape are gradually increased to form multiple stages of reinforcement heat transfer structures, and the specific surface areas of the multiple stages of reinforcement heat transfer structures are multiplied in sequence; the first-stage reinforcement heat transfer structures can transfer heat to an area far away from a heat radiation bottom plate rapidly in a reinforcement mode, and the second-stage reinforcement heat transfer structures (5) and the third-stage reinforcement heat transfer structures can transfer heat to phase change material far away from the heat radiation bottom plate rapidly to complete heat exchange.

The invention discloses a process for growing phi 8'' solar-grade Czochralski silicon monocrystalline by using an 18-inch thermal field. By adopting the 18-inch thermal-shielding thermal field and an upper-shaft magnetic fluid sealing device with a cooling system and combining the optimized parameter conditions of crystal-pulling processes, the invention enables the thermal field to have good heat preservation and obviously reduced energy consumption, enables gas to smoothly flow to be beneficial for the exhaustion of volatile matter, stabilizes crystallization, prolongs the service life of equipment and reduces the production cost; and in addition, the invention reduces magnet demagnetization and the evaporation of a magnetic fluid to avoid the air leakage and the slag dropping of the sealing of the magnetic fluid affecting the growth of the Czochralski silicon monocrystalline, improves the sealing performance and prolongs the service life, thereby ensuring the crystal-pulling processes of crystal leading, diameter equalization, shoulder rotation and the like to be stable and improving production efficiency and yield.

A magnetic rheological soft starter is used in mechanical transmission. In order to eliminate impact of clutch during starting, new material magnetic rheological fluid (MRF) is introduced as the power transmission medium, and magnetic field electromagnetic winding produces is used in altering the rheological characteristic and controlling transmitted torque to reach the aim of smooth starting. For small structure, great torque and reduced heat produced during operation, the present invention makes driving part in cavity holding driven part, adopts two electromagnetic windings to control the rheological characteristic of MRF in radial and axial work gap, and mounts heat pipe to the end cap of the driving part to lower its temperature. The present invention is used mainly in soft starting of mechanical unit, power transmission, speed regulation and overload protection.

The invention relates to a control method for a camera synchronous LED flash and fill-in light, which comprises the following steps: a width parameter of an optical pulse is calculated according to a shutter parameter; whether the calculation is completed or not is detected; if yes, the pulse width is set up according to the shutter parameter; whether the setting is finished is detected; if yes, a phase position parameter is obtained by searching a table according to the pulse width; whether the table search is finished is detected; if yes, the phase position is set up according to the phase parameter. Compare with the prior art, in the invention, LED light source flash pulse and shutter are synchronous, thus providing light source with high speed flash for a camera and reducing the energy consumption in the premise of guaranteeing light filling; by this means, the working temperature of the LED is reduced and the service life of the LED is prolonged. When a person faces the camera and feels the illumination of the light source is lower in the premise of guaranteeing image quality, the person to be shot has no lighting glaring sense, thus behaving natural in the shooting process.

The invention discloses a flower-like nano-WO3/graphene composite gas-sensitive material and a preparation method and an application thereof. According to the invention, oxidized graphene and soluble tungsten salt are compounded by a microwave-stirring hydrothermal method so as to prepare the flower-like nano-WO3/graphene composite gas-sensitive material. The content of graphene in the nano-WO3/graphene composite gas-sensitive material is 0.1-1.0%. The nano-WO3/graphene composite gas-sensitive material provided by the invention has unique and uniform morphology, has high sensitivity to aniline gas and has good selectivity. Operating temperature is as low as 80 DEG C. The preparation method adopts microwave heating and stirring. The technology is advanced, reaction time is short and cost is low.

The invention relates to a dual-damping and dual-power-generating combined damping device comprising a magnetorheological damping temperature difference power generating type damper and an electromagnetic damping temperature difference power generating type damper which are spaced by a magnetic isolating material and a sealing material to form working spaces independent from each other. The magnetorheological damping temperature difference power generating type damper and an electromagnetic damping temperature difference power generating type damper form a synergistic dual-damping damping and synergistic dual-power-generating working mode. The device is of a novel device structure formed by integration, the objective of optimizing and improving comprehensive performance of the device is achieved, and the device is applicable to damping of automobiles, trains, ships, tanks, airplanes, machinery, projects and bridges and vibrating energy recycling for power generation.

The invention relates to a low-temperature halogen-free lead-free solder paste. The solder paste is mixed by Sn-Ag-Bi-based lead-free solder powder added with P or rare earth elements and a rosin-based soldering flux. The soldering flux is basically composed of, by weight, 30-45% of rosin resin, 2-10% of an organic acid activator, 3-5% of a thixotropic agent, 2-5% of a corrosion inhibitor, 3-5% of a surfactant and the balance solvents. The solder paste has the advantages that the welding temperature is low, slag is reduced, and the solder paste is suitable for manual welding and printing welding with poor thermal shock resistance.

The invention relates to a dual-redundancy electro hydraulic servo actuator which comprises a double-outlet rod hydraulic cylinder and a single-outlet rod hydraulic cylinder which are connected in series, wherein one end of the double-outlet rod hydraulic cylinder extends outward, and is connected with load; the rodless cavity side of the single-outlet rod hydraulic cylinder is connected with a displacement sensor; and one end of the double-outlet rod hydraulic cylinder and the rodless cavity side of the single-outlet rod hydraulic cylinder are respectively controlled by a hydraulic control system. According to the invention, the double-outlet rod hydraulic cylinder and the single-outlet rod hydraulic cylinder are adopted to form the dual-redundancy electro hydraulic servo actuator, so that the defect of large occupied space for a dual-redundancy electro hydraulic servo actuator which is composed of two double-outlet rod hydraulic cylinders in series is overcome, thus the structure is more compact, because the control on a single-outlet rod return circuit has a cold and hot oil exchange process, the system working temperature is reduced, and the system works more stably.

The invention discloses a mothproof fabric and a preparation method thereof. The preparation method of the mothproof fabric comprises the following steps: weaving natural fibers into an inner layer, synthetic multifilament yarn into a surface course, and polypropylene fiber filament or polyethylene fiber filament fabric into a lapping layer, wherein the inner layer and the surface course are in grid shape; dying in dying liquid at a temperature of 60-105 DEG C for 10-120 minutes; washing with water; drying; and forming, wherein the dying liquid is a missible-oil aqueous solution, missible oil is formed by mixing pyrethroid and ether solvent in a mass ratio of 1:5 to 1:20; the mass ratio of the fabric to the dying liquid is 1:7 to 1:20; and the amount of the missible oil is 5-10% of the fabric weight. The method has short production flows, convenient operation, small consumption of a pyrethroid pesticide and low requirements for fiber material by adopting dying and the additional pyrethroid pesticide; and the fabric prepared by the method has favorable permeability, strong capability of resisting insect invasion and long anti-mosquito effect.

The invention provides browning treatment liquid for a printed circuit board. 1 L of the browning treatment liquid is prepared from 70 g/L-100 g/L of H2SO4, 20 g/L-60 g/L of H2O2, 15 mg/L-100 mg/L of NaCl, 30 mg/L-200 mg/L of CusO4.5H2O, 3 g/L-6 g/L of water-soluble methoxy polyethylene glycol, 4 g/L-12 g/L of a corrosion inhibitor, 2 g/L-3 g/L of 3, 5-dimethyl-2-mercapto benzimidazole, 0.01 g/L-0.5 g/L of polyquaternium-39 and the balance deionized water. The browning treatment liquid has high copper loading capacity, no black brown sediment is generated in a solution, the reactivity of the solution can still be kept even under the discontinuous production condition, and the performance of the solution does not need to be replaced. In addition, the browning treatment liquid is low in work temperature, short in work time, long in service life and suitable for high temperature. The circuit board manufactured through the browning treatment liquid is good in tearing strength, wet resistance and acid resistance, and no pink ring is generated.

The invention discloses a water-cooled magnetorheological soft start device, and belongs to the technical field of mechanical power transmission. The device comprises a drive rotator structure and a driven rotator structure, wherein a plurality of drive cylinders and driven cylinders are respectively plugged on drive cylinder sleeves and driven cylinder sleeves at intervals; the drive cylinder sleeves and the driven cylinder sleeves are respectively connected with left magnet-conducting shaft sleeves, right left magnet-conducting shaft sleeves, drive shafts and driven shafts through bolts; a sealing measure is arranged at each connection position; left magnetic yokes and right magnetic yokes are fixed with a magnet-conducting shell; magnet exciting coils and magnetic isolation discs are arranged in the left magnetic yokes and the left magnetic yokes; left bearing seats and right bearing seats are respectively fixed on outer sides of the left magnetic yokes and the left magnetic yokes;left bearings and right bearings used for bearing the drive shafts and the driven shafts are respectively arranged in the left bearing seats and the right bearing seats; a water inlet, a water outlet, a groove, a liquid injecting opening and a liquid discharging opening are formed in the magnet-conducting shell; a liquid injecting plug screw and a liquid discharging plug screw are arranged on theliquid injecting opening and the liquid discharging opening; and a plurality of groups of rotating sealing rings are arranged in the groove. The water-cooled magnetorheological soft start device has the advantages of compact structure, large transmission torque, high radiating performance, high slip frequency power and wide slip frequency range.

The invention discloses a packaging method for white light LED surface light source module, which insists of processing steps such as making circuit boards, fixing crystal, bonding, packaging basic bond line and so on. The invention adopts steps: distributing multiparticulate miniwatt LED chips on a circuit board and packaging integrally to form a high power LED light source, dispersing the heat source, reducing heat productivity on a unit area, reducing heat dispersion requirement standard. Adopting white colloid as solid crystal glue can improve more than 70% of back face emergent light utilance. The basic bond line packaging makes microcosmic light source points distribute uniformly on a bigger area, reduce luminous intensity on a unit area. The light flux on a unit area of traditional LED light source is more than 100 lm/cm<2> generally, while light flux on a unit area of the invention is less than 51 lm/cm<2> generally, thereby glaring is overcame.

The invention relates to a gas sensor, in particular to a quartz crystal resonator which is sensitive to ethanol, and preparation and application thereof, comprising an AT-cut quartz wafer and a gold electrode fixed on the quartz wafer, wherein, the outer surface of the gold electrode and/or the quartz wafer is coated with an ionic liquid membrane. The resonator is applied to a conventional QCM sensor to prepare a QCM ethanol gas sensor, and the operation principle is the quartz crystal microbalance technology; the response frequency of the sensor is reduced with the fractional increase of the surface quality of the resonator caused by the absorption of the ethanol gas on the surface of a sensitive membrane of the quartz resonator, and the reduced value of the frequency and the concentration of the ethanol gas are linear. The gas sensor has the advantages of simple structure, small size, fast and real-time response, high sensitivity, good selectivity, no need of analog to digital conversion for the output of frequency signals, convenient batch production and the like, and is particularly suitable for measuring the concentration of the ethanol gas in the air in real time.

The present invention provides an organic aluminum plating method for a neodymium iron boron permanent magnetic material. The method comprises the following steps: (1) carrying out chamfering and polishing; (2) carrying out degreasing and deoiling; (3) carrying out pickling and derusting; (4) carrying out organic aluminum plating: adopting an aluminum plating solution to carry out aluminum layer plating on the surface of the neodymium iron boron permanent magnetic material under the protection of inert gas, wherein the aluminum plating solution comprises AlCl3, LiAlH4 and tetrahydrofuran; (5) passivating the aluminum plating layer. With the organic aluminum plating method of the present invention, the neodymium iron boron permanent magnetic material can have the excellent corrosion resistance.

The invention discloses a solar photovoltaic waste heat-joule heat gradient utilization seawater desalination system, and belongs to the field of renewable energy source utilization. The system mainlycomprises a high-transmittance glass cover plate, a solar photovoltaic cell, heat conduction silica gel, a heat conduction aluminum plate, a seawater flow channel, an electric heating layer, a hydrophobic film layer, a condensate flow channel, aheat preservation and insulation layer a seawater storage tank, a condensate collecting tank, a washing tank and an efficient fin radiator. The system iscomposed of multiple layers of seawater desalination devices. The desalination devicesare arranged in the heat preservation and insulation layer, the high-transmittance glass cover plate, the solar photovoltaic cell, the heat conduction silica gel, the heat conduction aluminum plate, the electric heating layer, the hydrophobic film layer, the seawater flow channel, the seawater storage tank and the condensed water collection tank are sequentially arranged in the heat preservation and insulation layer from top to bottom. Waste heat and electric energy generated by power generation of the solarphotovoltaic cell are utilized, energy is utilized in situ or in a gradient mode to participate in sea water desalination, solar energy is utilized to the maximum extent, and meanwhile the evaporationefficiency and the sea water desalination capacity of the system are greatly improved.

The invention relates to a submersed marine fishing lamp with a high-power blue-green LED as a luminous source. The existing auxiliary equipment used in the luring and fishing of fishes mainly adopts a metal halide lamp which has wide light source wavelength range, after filtration in the sea, the remaining blue-ray component is little and the other colors are all absorbed by the seawater, thus causing great waste of energy resource. The purpose of the invention is to provide the submersed high-power blue-green LED marine fishing lamp. The structure of the invention consists of a high-power blue-green LED arranged on a lamp body; in the lamp body, an upper shell is fixed on the upper end of a main shell which is sequentially fixed with a circulating water insulated tube, a lower shell, a glass cover and a protecting cage from inside to outside; both the external surfaces of the lower shell and a lower baffle are fixed with a high-power blue light LED, the cable plywood used in the upper shell is fixed and connected with a power board. The application of the lamp is that the fishes in the sea are gathered by the blue-green light with the wavelength from 465nm to 490nm given out by a light source module, thus achieving the purposes of saving energy and improving the efficiency of fishing.

The invention discloses a graphene/molybdenum disulfide compounding-based gas sensitive material and a preparation method thereof, relates to a gas sensitive material and a preparation method thereof, and aims at solving the technical problem that intrinsic graphene gas sensor nanoparticles only have high sensitivity for a few gases. The outer surface of graphene is coated by molybdenum disulfide. The preparation method comprises the following steps: I, cooling concentrated sulfuric acid, adding natural flake graphite and potassium permanganate, stirring, adding a mixed solution formed by hydrogen peroxide and distilled water, centrifuging and cleaning, and dissolving a precipitate in deionized water to obtain a solution; and II, dissolving sodium molybdate, cysteine and sodium hexadecyl benzene sulfonate in distilled water, adding the solution obtained in the step I, placing in a reaction kettle, and carrying out centrifugal cleaning and freeze drying to obtain the graphene/molybdenum disulfide compounding-based gas sensitive material. The composite material is high in selectivity and sensibility. The graphene/molybdenum disulfide compounding-based gas sensitive material and the preparation method thereof belong to the field of preparation of gas sensitive materials.

The invention discloses a bell-less top distributing gear of furnace, belonging to technical field of metallurgical industry. The invention adopts sealed cooling, a water-cooling venturi tube with pipe laying and a water-cooling chassis. A motor drives a chute to rotate and tilt; wherein, the motor drives the nut of the ball screw assembly to rotate and then drives the lead screw and the lifting rotary frame connected with the lead screw to move up and down in order to achieve chute to tilt for Alpha angle. The invention has the advantages of high coaxiality, high transmitting precision, long service life of the critical component, easy manufacture, light weight and low cost. The tilting Alpha angle of the chute and the stationarity of the tilting movement of the chute can be checked during the producing process of the furnace by the invention. The invention can be used in charging operation of furnace roof and also is suitable for shaft furnace or smelting reduction furnace which need to feed from the roof to the closed space and distribute regularly.

The invention discloses a preparation method of an ethanol gas sensor component having an ultrafast response recovery property. In the preparation method, LaFexO3 nano particles in non-stoichiometric ratio prepared through a sol-gel method are employed as a working substance to prepare a beside-heating-type ceramic tube gas sensor component. By means of reduction of a relative element ratio of iron to lanthanum in a precursor, the carrier concentration is increased and the resistance of the component is reduced. By means of selection of a proper La/Fe element ratio, size of crystal grains is reduced and oxygen adsorption capacity is improved, so that the gas sensor is improved in sensitivity on ethanol, is reduced in working temperature and is reduced in response recovery time. A LaFe0.8O3 beside-heating-type ethanol gas sensor prepared in the invention can reach 138 in the sensitivity on ethanol in 1000 ppm at the working temperature of 140 DEG C, wherein the response and recovery times are respectively 1 s and 1.5 s. The gas sensor is less than 22 in all sensitivities on methane, acetone, carbon dioxide and glycerol in 1000 ppm. The gas sensor is high in sensitivity, is low in the working temperature, is ultrafast in response recovery property and is high in selectivity at the same time on ethanol, and is low in cost and is environmental-friendly.

The invention discloses a multi-stage structure nanometer In2O3/graphene composite and a preparation method and application thereof. The composite is of a brick-shaped structure. The preparation method includes the steps of making indium salt capable of being dissolved in ethylene glycol, reduced graphene oxide and precipitator ammonium hydroxide have a chemical reaction under the microwave heating conditions on the gas-liquid interface formed by an ethylene glycol solution and ammonium hydroxide steam, bringing away the reaction product through a rolling ethylene glycol solution, and continuing to generate a new product. The composite has the advantages that original nanometer particles of nanometer In2O3/graphene prepared through a microwave gas-liquid interface method are small and uniform; the brick-shaped nanometer structure is formed with the original nanometer particles through self-assembling, and the multi-stage structure nanometer In2O3/graphene composite has good gas-sensitive performance for nitric oxide gas at the temperature of 100 DEG C and is high in selectivity.

The present invention provides a LED street lamp having high heat dispersion, including a LED source and its driving circuit, the LED source and its driving circuit are fixed on the aluminum base circuit wafer, characterized in that the aluminum base circuit wafer is fixed on the metallic lamp case, being integrity with radiator and lamp. The LED street lamp of the invention greatly enhances the radiating performance of the LED circuit wafer, reduces working temperature of LED directional light, enhances working life of LED source.

The invention discloses leadless ZnO-Sb2O3-P2O5 system low melting point glass, which mainly comprises the following components in percentage by mass: 30 to 60 percent of P2O5, 10 to 30 percent of ZnO, 5 to 30 percent of Sb2O3, 2 to 15 percent of Li2O, Na2O and K2O, 5 to 20 percent of MgO, CaO, SrO and BaO, and 1 to 10 percent of MnO and MnO2. The glass also comprises the following components in percentage by mass: 0 to 5 percent of SiO2, 0 to 10 percent of B2O3, and 0 to 15 percent of Al2O3. The working temperature of the phosphate glass is not more than 500 DEG C, the chemical stability is high, and the swelling coefficient is moderate, so the phosphate glass can be widely applied in the fields of middle and low temperature sealing of electronic products, manufacturing of high-temperature resistant paints, inflaming retarding when filled with a polymer material, and the like.

The invention discloses a coated aluminum substrate for drilling a PCB (Printed Circuit Board) and a preparation method of the coated aluminum substrate. The method comprises the following steps: taking 40-50 parts by weight of two or more of polyurethane, acrylic ester, aqueous phenolic resin and aqueous epoxy resin to form a component A1, then taking 40-55 parts by weight of two or more of polyoxyethylene, polyethylene glycol, glycerin, vinyl acetate and polyving akohol to form a component A2, taking 5-8 parts by weight of accessory ingredient, mixing the component A1, the component A2 and the accessory ingredient to obtain emulsion, coating the surface of an aluminum foil with the emulsion in a roller coating manner to prepare finished product. By using the characteristics of the surface layer resin of the aluminum foil of low hardness, low melting point, strong cohesive property and excellent water solubility, the coated aluminum substrate for drilling the PCB is capable of improving the drilling precision of a drill point in the drilling process, effectively reducing the working temperature of the drill point, prolonging the service life of the drill point and improving the hole wall quality of the drill hole.

The invention discloses a method for preparing Li-Mg-N-H hydrogen storage material. The mixture of the nitride or amino-compound of Li and Mg, the nitride or amino-compound of Mg is loaded in a stainless steel tank and evenly blended by a mechanical mixing or mechanical ball milling way; the evenly blended mixture is loaded in a sintering furnace, the sintering furnace is vacuumized or charged with inert gases and is heated to the temperature range from 250 to 350 DEG C for heat preservation and then the Li-Mg-N-H hydrogen storage material is obtained; the Li-Mg-N-H hydrogen storage material is loaded into a ball milling tank and undergoes ball milling process on a ball mill, and the grain diameter of the sample powder processed with ball milling is smaller than 100nm. The preparation method has simple operation, easy control and low cost. The Li-Mg-N-H prepared and processed by the invention has high hydrogen storage capacity, low working temperature and high speed of hydrogen absorbing and discharging and good reversibility, thus being the hydrogen storage material with excellent performance and being suitable for the storage and transportation of hydrogen.

A silica gel absorbent with nano pores is prepared through immersing inorganic fibrous paper in water glass for 10-24 hr, drying for 10-24 hr, immersing in aquous solution of precipitant for 12-24 hr, drying in air, immersing in acid for 12-24 hr, water washing until it become neutral, drying in air, and program heating. It can be used as demoistening core of air conditioner. Its advantages are high adsorptive power, and low energy consumption and regenerating temp.