Abstract: A tumor radiotherapy planning design method and apparatus, an electronic device, and a computer storage medium are provided, including: obtaining a current optimization parameter vector set, and calculating a current cost function value; randomly correcting the current optimization parameter vector set to generate alternative optimization parameter vector sets; then performing planning parameter optimization, and calculating corresponding total cost function values; determining current optimal or suboptimal alternative optimization parameter vector sets according to the total cost function values, sampling to update the current optimization parameter vector set and the current cost function value according to the total cost function values of the current alternative optimization parameter vector sets, and then performing an iteration repeatedly until a convergence condition is satisfied; and outputting an optimal optimization parameter vector set after the iteration, determining planning parameters, and calcu

Abstract: A composition of heat-expandable microspheres and an application thereof are provided. The composition includes heat-expandable microspheres and a solvent. The particle size of the heat-expandable microspheres is 5 ?m?D?40 ?m, preferably 8 ?m?D?20 ?m. The thickness of the walls of at least 60% of the heat-expandable microspheres is ?5 ?m, preferably the thickness is ?3 ?m. The solvent at least comprises one organic solvent having a boiling point of above 220° C. A thermal expansion coating containing the composition has a stable structure, relatively high resistance to thermal shrinkage, relatively high mechanical strength and adhesion, can be applied in the fixation of high temperature resistant parts, and can maintain the bonding stability thereof when placed long-term in a high temperature environment (140-180° C.).

Abstract: A tumor radiotherapy planning design method and apparatus, an electronic device, and a computer storage medium are provided, including: obtaining a current optimization parameter vector set, and calculating a current cost function value; randomly correcting the current optimization parameter vector set to generate alternative optimization parameter vector sets; then performing planning parameter optimization, and calculating corresponding total cost function values; determining current optimal or suboptimal alternative optimization parameter vector sets according to the total cost function values, sampling to update the current optimization parameter vector set and the current cost function value according to the total cost function values of the current alternative optimization parameter vector sets, and then performing an iteration repeatedly until a convergence condition is satisfied; and outputting an optimal optimization parameter vector set after the iteration, determining planning parameters, and calcu

Abstract: A rare earth permanent magnet, and a preparation method therefor are provided. The rare earth permanent magnet M and the preparation method may effectively improve the grain boundary anisotropy of the magnet, provide more diffusion channels through which a heavy rare earth diffusion source can enter the inside of the magnet, such that the heavy rare earth diffusion source is more effectively diffused into the magnet, the intrinsic coercivity of the magnet is greatly improved, and a magnet N having high intrinsic coercivity is obtained. Using the same amount of a heavy rare earth diffusion source material, the method produces magnet N having high intrinsic coercivity amplification with reduced production costs.

Abstract: The permanent magnet comprises a main phase structure of R2T14B crystal grains, and R is a rare earth element; T comprises at least Mn, Fe, and optionally a transition metal comprising Co; B is boron; the permanent magnet further comprises Mn and heavy rare earth elements which are distributed in a grain boundary in a diffusion mode. The heavy rare earth element is selected from at least one selected from Dy, Ho and Tb. According to the rare earth permanent magnet prepared through the preparation method, more heavy rare earth elements can be diffused into the magnet core along the grain boundary, Hcj distribution of the permanent magnet is improved, and meanwhile the corrosion resistance and the mechanical property of the permanent magnet are improved.

Abstract: The present disclosure discloses a laser radar for meteorological observation, and specifically relates to the field of meteorology. The laser radar comprises a base. According to the present disclosure, air pressure at the bottom of 301 is increased by injecting gas into the interior of 202, so that the 301 falls off from 201, and the disassembly between the stable seat and the connecting sleeve plates is realized; with regard to the disassembly process of the connecting sleeve plates and the base, the magnetic pole of a positioning electromagnet is changed mainly by switching the current direction of an external coil of the positioning electromagnet, so that the positioning electromagnet is separated from the locking magnet, thereby facilitating the detachment of the base and the connecting sleeve plates in combination with the linkage component, and the disassembly process of the whole device.

Abstract: The present disclosure discloses a laser radar for meteorological observation, and specifically relates to the field of meteorology. The laser radar comprises a base. According to the present disclosure, air pressure at the bottom of 301 is increased by injecting gas into the interior of 202, so that the 301 falls off from 201, and the disassembly between the stable seat and the connecting sleeve plates is realized; with regard to the disassembly process of the connecting sleeve plates and the base, the magnetic pole of a positioning electromagnet is changed mainly by switching the current direction of an external coil of the positioning electromagnet, so that the positioning electromagnet is separated from the locking magnet, thereby facilitating the detachment of the base and the connecting sleeve plates in combination with the linkage component, and the disassembly process of the whole device.

Abstract: The present disclosure relates to a field stage lighting, in particular to an LED projection lamp. The LED projection lamp includes an optical lens cover, a first aluminum substrate, a second aluminum substrate, and a first housing. A first glass lens bracket, a glass lens, and a second glass lens bracket are respectively arranged on an upper end of the first aluminum substrate. A water ripple sheet is arranged on a lower end of the first aluminum substrate. Condensing lens is arranged on an upper end of the second aluminum substrate. A motor is arranged on a lower end of the second aluminum substrate. A second housing is arranged on a lower end of the first housing.

Abstract: A method for preparing an R—Fe—B based sintered magnet. The method includes: 1) preparing a R1—Fe—B-M alloy, pulverizing the R1—Fe—B-M alloy to yield a R1—Fe—B-M alloy powder, adding a heavy rare earth powder of R2 or R2X and subsequently adding a lubricant to the R1—Fe—B-M alloy powder and uniformly stirring to form a mixture, where R1 being Nd, Pr, Tb, Dy, La, Gd, Ho, or a mixture thereof; M being Ti, V, Cr, Mn, Co, Ga, Cu, Si, Al, Zr, Nb, W, Mo, or a mixture thereof; R2 being at least one from Tb, Dy, and Ho; X being at least one from O, F, and Cl; 2) pressing the mixture obtained in step 1) to form a compact, and sintering the compact in a pressure sintering device in vacuum or in an inactive gas atmosphere to obtain a magnet; and 3) aging the magnet obtained in step 2).

Abstract: A method for preparing an R—Fe—B based sintered magnet. The method includes: 1) preparing a R1—Fe—B-M alloy, pulverizing the R1—Fe—B-M alloy to yield a R1—Fe—B-M alloy powder, adding a heavy rare earth powder of R2 or R2X and subsequently adding a lubricant to the R1—Fe—B-M alloy powder and uniformly stirring to form a mixture, where R1 being Nd, Pr, Tb, Dy, La, Gd, Ho, or a mixture thereof; M being Ti, V, Cr, Mn, Co, Ga, Cu, Si, Al, Zr, Nb, W, Mo, or a mixture thereof; R2 being at least one from Tb, Dy, and Ho; X being at least one from O, F, and Cl; 2) pressing the mixture obtained in step 1) to form a compact, and sintering the compact in a pressure sintering device in vacuum or in an inactive gas atmosphere to obtain a magnet; and 3) aging the magnet obtained in step 2).