31results about How to "Reduce initial resistance" patented technology

The invention provides a metal-film filtering screen and an air purifying device, and relates to the field of air purification. The metal-film filtering screen is mounted in an air filtering device; the air filtering device is provided with an air inlet and an air outlet; the metal-film filtering screen comprises a medium-efficiency filtering screen and a high-efficiency filtering screen. The medium-efficiency filtering screen more approaches the air inlet relative to the high-efficiency filtering screen; the medium-efficiency filtering screen and the high-efficiency filtering screen both comprise multiple layers of filtering plates; a gap exists between two adjacent layers of the filtering plates; the filtering plates are provided with multiple filtering holes; the filtering plates are made from intermetallic compounds. As the filtering screen is made from a special intermetallic compound, the purification effect is good; a material is quite environment-friendly; moreover, the metal-film filtering screen can be circularly rinsed and repeatedly used; after a client purchases a fresh air ventilator with the filtering-screen material, no any consumable-material expenses exist. In this way, the fussy consumable material replacing action is virtually decreased for the client; meanwhile, the cost is also greatly saved for the client.

The invention relates to a dust absorption device, which is especially suitable for absorbing the dust of electric welding soot with the grain diameter less than 15 millimeters. The device comprises a plurality of layers of flatbed typed filter screens or/and rippled filter screens with different meshes that are placed inside the frame in an overlapped way and made of stainless material; the periphery of each layer of flatbed typed filter screens or/and rippled filter screens are mutually overlapped via a U-shaped connecting component; a pressure frame is arranged between an upper frame and the U-shaped connecting component, and the pressure frame tightly presses the U-shaped connecting component via a plurality of adjustment bolts arranged on the upper frame; wherein, the outer layers of the plurality of layers of filtration screens are provided with strengthened filtration screens respectively. The multilayered overlapped combination of 400 to 1200 meshes forms larger spacing, which enlarges the filtration area and reduces the initial resistance of the device. The invention has the advantages of simple structure, large dust absorption amount within average area and high purification efficiency. Meanwhile, the filtration screens are made of stainless material, which has the advantages of anticorrosion, easy cleaning and maintenance and long service life, so that the operating cost is low, the energy consumption is low and the effect of energy conservation is remarkable.

The application discloses an antistatic composite filter material and a preparation method thereof, comprising a first filter layer, a second filter layer and stainless steel wire, and the two filter layers are respectively a G5 non-glue filter layer and a G3 non-glue filter layer, The overall structure is formed by two press-fits, and the stainless steel wire needle-punched hook is connected. The present invention improves the filtration efficiency, has a certain flame-retardant effect and anti-static effect, and is not easy to deform, and increases the strength and oxidation resistance of the filter material. Has a long service life.

The invention relates to a transformer immersion oil filter paper. The transformer immersion oil filter paper comprises an outer filter bag, a solid waste filtering layer and a water absorbing layer are arranged in the outer filter bag, and the solid waste filtering layer is arranged above the water absorbing layer. The transformer immersion oil filter paper has a large filtering area, a low initial resistance, a high waste scrap capacity and a long service life. Solids in old transformer oil undergo three-stage filtration by a scrap accommodating layer, a transition layer and a fine filter layer, so solid impurities can be removed, the filtration efficiency is high, and the filtration effect is good; and water in the old transformer oil can be adsorbed by the water absorbing layer to complete dewatering work, and the filtering work and the dewatering work are simultaneously completed, so the operation is simplified, manpower and material resources are saved, and the implementing effect is good.

Provided is a non-aqueous electrolytic solution for a lithium ion secondary cell that can reduce the initial resistance of the lithium ion secondary cell and can suppress the increase in resistance when the lithium ion secondary cell is allowed to stand at high temperature. The non-aqueous electrolytic solution for a lithium ion secondary cell disclosed herein includes a light metal salt represented by the following formula (I) and a silyl sulfate compound represented by the following formula (II). The content of the light metal salt in the non-aqueous electrolytic solution for a lithium ion secondary cell is 0.1% by mass or more and 1.5% by mass or less. The content of the silyl sulfate compound in the non-aqueous electrolytic solution for a lithium ion secondary cell is 0.1% by mass or more and 5.0% by mass or less (each symbol in the formulas is as defined in the specification).

The invention provides a non-woven needle of fabric. The non-woven needle comprises a needle rod segment, a work segment and a needle point segment. The work segment and the needle point segment longitudinally extend in the first direction in sequence. The work segment is a triangular spiral body and is provided with a plurality of hook tooth sets, each hook tooth set comprises three hook teeth located on the same horizontal plane, and the hook teeth in the hook tooth sets are located on the edges of the work segment and are gradually enlarged in the second direction opposite to the first direction. The hook tooth sets gradually enlarged in equal proportion are arranged on the spiral edges of the work segment of the non-woven needle of the fabric, so that the probability that the hook teeth hook fabric fibers is reduced, initial puncture resistance of the non-woven needle is reduced, and therefore work efficiency is improved, and the phenomenon of needle breakage is reduced.

The present disclosure relates to a cathode active material for a lithium secondary battery, a preparation method therefor, and a lithium secondary battery comprising same, and the cathode active material includes a lithium nickel cobalt manganese-based oxide represented by Chemical Formula 1 including secondary particles obtained by agglomerating at least one primary particle, and a metal oxide particles having a nano-sized average diameter (D50) and disposed inside the secondary particles.

Li_a[Ni_xCo_yMn_z]_tM_1-tO_2-pX_p.  [Chemical Formula 1]

The invention discloses a high-dust-holding medium-efficiency trapezoidal filter bag in the technical field of medium-efficiency bag filters, which comprises a filter bag body with a trapezoidal vertical section and a mounting part mounted on the bottom wall of the filter bag body, and the area of the cross section of the filter bag body is gradually increased from bottom to top. According to the medium-efficiency trapezoidal bag type filter, the filter material is formed by compounding hardened hot air cotton, two-component melt-blown fibers, large-diameter melt-blown fibers and the anti-sticking layer, and automatic trapezoidal sewing is performed through customized and developed ultrasonic equipment, so that the filter material is high in structural strength and good in filling power; the efficiency of the bag type filter is guaranteed, the initial resistance of the filter is reduced, and the dust holding capacity is greatly improved due to the fact that the filter material has enough bulkiness.

The invention provides a non-woven needle which comprises a needle bar section, a work section and a needle point section, wherein the work section and the needle point section sequentially extend along a first direction; the work section comprises a first local section, a second local section and a first reducing cone for connecting the first local section with the second local section; a plurality of first hook teeth are annularly distributed on the surface of the first local section; a plurality of second hook teeth are annularly distributed on the surface of the second local section; the diameter of the first local section is greater than that of the second local section; and the depths of the first hook teeth are greater than the depths of the second hook teeth. According to the non-woven needle disclosed by the invention, the work section of the non-woven needle is arranged into the first local section and the second local section of which the diameters are gradually reduced; and the first hook teeth and the second hook teeth are spirally and annularly arranged on the surfaces of the first local section and the second local section. Due to the adoption of the structure, the probability that fabric fibers are hooked by the hook teeth on the surface of the non-woven needle is remarkably improved, the initial resistance of needling is reduced and the production efficiency is increased.

The present invention provides a positive electrode material for lithium secondary batteries, having: a positive electrode active material containing Li; and a cover disposed on the positive electrode active material, and containing Li and F, and further containing one or two or more cover elements from among Al, Ti, Zr, Ta and Nb. With a Point a as an arbitrary point of the cover in contact with the positive electrode active material, a Point c as a point on the surface of the cover at a shortest distance from the Point a, and a Point b as a midpoint between the Point a and the Point c, an analysis of the Point a, the Point b and the Point c by X-ray photoelectron spectroscopy yields a ratio of Li concentration at the Point a with respect to the Li concentration at the Point b is 1.1 or higher and lower than 10.8, and a ratio of F concentration at the Point c with respect to F concentration at the Point b is 1.1 or higher and lower than 51.1.

The invention relates to impermeable self-compacting concrete and a preparation method thereof, and belongs to the technical field of concrete preparation. The preparation method comprises the following steps: firstly, taking aluminum sulfate as an aluminum source, urea as a precipitator and methyl amyl alcohol as a dispersing agent, preparing superfine spherical aluminum oxide with the particle size of 200nm, high dispersity and good spherical roundness through an auxiliary homogeneous precipitation method, then preparing porous silicon carbide, adhering tetraethoxysilane into the porous silicon carbide, and performing packaging with paraffin to prepare a self-made dense filler. The two self-made additives are used for improving the compactness and the impermeability of the final concrete material, and the concrete has a wide application prospect.