4 results about "Lead tetraoxide" patented technology

The invention discloses a PTC ceramic material and a preparation method thereof, and relates to the technical field of PTC, and the PTC ceramic material is prepared from the following components: 50-65 parts of barium titanate, 12-16 parts of lead tetraoxide, 0.1-0.3 part of yttrium oxide, 0.1-0.3 part of lanthanum oxide, 6-15 parts of modified silicon boride, 4-10 parts of aluminum oxide, 1-3 parts of ammonium polyacrylate, and 3-6 parts of polyvinyl alcohol. Through synergistic cooperation of a barium titanate main body and functional fillers such as modified silicon boride, leap-type improvement of the comprehensive performance of the PTC ceramic material is realized, on the basis of maintaining excellent PTC characteristics, the heat conductivity coefficient and the breaking strength of the material are effectively improved, the thermal shock resistance and the mechanical reliability are remarkably enhanced, and the PTC ceramic material has good application prospects. The method is especially suitable for the high-end application fields of automotive electronics, industrial control, high-power LED driving and the like.

The invention belongs to the technical field of chemical engineering, and relates to a composition for a detonation sound agent, the detonation sound agent and a preparation method and application of the detonation sound agent. The technical problems that in the prior art, pyrotechnic composition and aluminum magnesium alloy powder serve as raw materials, potential safety hazards exist in the preparation and storage process, sulfur dioxide generated after combustion easily forms acid rain, and the detonation sound value does not reach the standard are solved. The invention provides a composition for a detonation sound agent, which comprises the following raw materials: 75-85 wt% of lead tetraoxide, 10-15 wt% of aluminum-silicon alloy powder and 5-10 wt% of nitrocellulose gum solution, and has the effects of high detonation sound value, high stability and safety, and suitability for large-scale industrial production and use. The invention further provides a detonation sound agent and a preparation method of the detonation sound agent. Meanwhile, the invention further provides application of the detonation sound agent in preparation of the bird repelling bomb, when the explosive quantity is 300 mg, the set-off sound level value at the position 2 m away from the acting position can reach 120 dB or above, and the good high-altitude bird repelling effect is achieved.

The utility model discloses an X-ray emitter. The X-ray emitter is characterized in that an open window is formed in the peripheral wall of an X-ray shielding barrel in a penetrating manner; the X-ray tube is mounted in the X-ray shielding barrel; the separator is provided with a first window in a penetrating manner, a mounting table is arranged at the bottom of the separator, and the separator is made of a lead tetraoxide material; the beryllium window is mounted on the mounting table; wherein the isolation piece is installed on the open window, the beryllium window penetrates through the open window to be embedded into the X-ray shielding barrel, and a ray emitting port of the X-ray tube, the beryllium window and the first window are in one-to-one correspondence in position to form a ray emitting window. The isolation piece made of the lead tetraoxide material is designed, the X-ray emission window is manufactured in a rubber sealing gasket mode, the ray shielding requirement is met, the oil sealing function is achieved, insulativity is good, and installation is easy. And meanwhile, the end cover mounting structure made of the lead tetraoxide material is adopted, so that the X-ray tube is convenient to assemble, and an insulation design is also adopted.

This application relates to the field of ceramic materials technology, specifically disclosing a ceramic material for PTC thermistors and its preparation method. The ceramic material for PTC thermistors includes the following raw materials: barium titanate, silane-modified alumina-coated lead tetroxide-silicon boride in-situ composite powder, rare earth oxides, alumina, ammonium polyacrylate, and polyvinyl alcohol. This application adds the silane-modified alumina-coated lead tetroxide-silicon boride in-situ composite powder to the ceramic material. The alumina directionally coats the lead tetroxide, effectively suppressing the volatilization of lead vapor during high-temperature sintering and improving the environmental friendliness of the ceramic material. Simultaneously, the in-situ composite bonding of lead tetroxide and silicon boride, combined with silane modification, improves the interfacial bonding ability between the composite powder and the barium titanate matrix, reducing internal stress during ceramic sintering and improving the mechanical properties of the ceramic material.