9results about How to "High shielding efficiency" patented technology

The application belongs to the field of new materials, and discloses a lead-free perovskite X-ray shielding composite material and a preparation method and application thereof, and comprises the following steps: mixing ANF / DMSO dispersion liquid with ethanol to obtain re-protonated ANF dispersion liquid; mixing the re-protonated ANF dispersion liquid, CsI powder and ethanol, and stirring to obtain two portions of the same CsI / ANF dispersion liquid; mixing re-protonated ANF, Cs3Bi2I9 powder and ethanol, and stirring to obtain Cs3Bi2I9 / ANF dispersion liquid; sequentially filtering the first portion of CsI / ANF dispersion liquid, the Cs3Bi2I9 / ANF dispersion liquid and the second portion of CsI / ANF dispersion liquid by using a gel-gel method, and vacuum hot-pressing to obtain a composite gradient film with a biomimetic symmetrical structure, which is used as a lead-free perovskite X-ray shielding composite material; and the application realizes continuous and efficient X-ray shielding effect, and can improve the mechanical flexibility and thermal stability of the material.

The invention provides an X-ray composite radiation shielding material and a preparation method and application thereof, and belongs to the technical field of radiation protection. The photoelectric effect and the scattering effect of X-rays in the material are remarkably enhanced by using high atomic number elements contained in the metal oxide, so that the transmittance of the X-rays is effectively reduced. Meanwhile, the oxide material has good chemical stability and environmental friendliness, and the toxicity and aging problems caused by a traditional lead-based shielding material can be avoided. The prepared composite radiation shielding material has the advantages of being low in cost, light in weight, easy to process, good in flexibility, non-toxic, environmentally friendly and the like, the shielding efficiency of an X-ray shielding coating reaches up to 70% or above when the X-ray photon energy is 70 kV or below, and the generated secondary reflectance can be reduced by 35-80% compared with lead.

The utility model relates to the technical field of electromagnetic shielding materials, and provides a bondable electromagnetic shielding composite foam board and a navigation model. The bondable electromagnetic shielding composite foam board comprises a release paper layer, an epoxy resin layer and a polyurethane foam shielding layer, and the polyurethane foam shielding layer is made by a foaming technology; wherein the epoxy resin layer is clamped between the polyurethane foam shielding layer and the release paper layer, and the release paper layer is attached to the lower surface of the epoxy resin layer. According to the bondable electromagnetic shielding composite foam board and the navigation model, the density of the material can be further reduced by adopting the foaming polyurethane and introducing the foam holes, the shielding performance is improved through multiple reflection and absorption of the foam holes to electromagnetic waves, and the potential application field of the electromagnetic shielding material is widened.

The utility model relates to a cable, and specifically relates to a dynamic network Category 6 cable for a mechanical arm. The utility model aims to provide the dynamic network category 6 + cable for the mechanical arm, and the cable still has the advantages of low attenuation, high transmission rate and high-frequency support under the working condition of high-intensity movement, and has the characteristics of high flexibility, torsion resistance, tensile resistance and stable signal transmission. According to the technical scheme, the dynamic network Category 6 + cable for the mechanical arm is characterized by comprising a cable core, and an outer shielding layer, a belting layer and an outer protection layer which are sequentially coated outside the cable core from inside to outside, the cable core comprises a plurality of twisted pairs which are arranged in parallel along the length direction of the cable and are coated with inner shielding layers; the twisted pair wires adopt different twist pitches so as to reduce electromagnetic crosstalk between the twisted pair wires. The twisted pair wire comprises two twisted wires, and each wire comprises a conductor, and a first insulating layer, a second insulating layer and a third insulating layer which are sequentially coated on the conductor from inside to outside.

The application discloses an electrical equipment and belongs to the technical field of electrical equipment. The electrical equipment comprises a circuit board, a cover body, a first conductive piece group and a second conductive piece group, the circuit board is provided with a device to be shielded; the cover body is covered outside the device to be shielded; the first conductive piece group is arranged on the circuit board and located outside the cover body, the first conductive piece group comprises a plurality of first conductive pieces which are spaced apart; the second conductive piece group is arranged on the circuit board and located inside the cover body, the second conductive piece group comprises a plurality of second conductive pieces which are spaced apart, and the first conductive pieces and the second conductive pieces are staggered. By arranging the first conductive pieces and the second conductive pieces which are staggered on the outside and the inside of the cover body respectively, the shielding effect can be enhanced, and the manufacturing and maintenance costs can be reduced.

The invention belongs to the technical field of nuclear magnetic resonance logging, and discloses a nuclear magnetic resonance logging instrument probe. Comprising a center support, a magnet assembly, a magnet protection shell, a magnetic core assembly and a magnetic core protection shell. The central support is provided with a mounting shaft and radial limiting parts at two ends. The magnet assembly is mounted on the mounting shaft, is positioned between the two limiting parts, comprises a first semi-cylinder group formed by splicing a plurality of small magnets on the upper side and a second semi-cylinder group formed by splicing a plurality of large magnets on the lower side, and is used for generating a radially enhanced static magnetic field. And the magnet protection shell is formed by buckling an upper shell and a lower shell which respectively cover the first semi-cylinder group and the second semi-cylinder group. The arc-shaped magnetic core assembly is attached to the periphery of the upper shell to guide a magnetic circuit and enhance a radio frequency magnetic field, and the outer side of the arc-shaped magnetic core assembly is coated with a magnetic core protection shell connected with the magnet protection shell. The magnetizing directions of the large and small magnets are tangentially arranged along the circumference of the probe; and the lower shell is made of a magnetic conductive material to form a magnetic shielding structure for shielding a stray magnetic field at the bottom. The probe can significantly increase the detection distance.

The utility model belongs to the technical field of beam limiting devices, and particularly relates to a shielding assembly for a speed limiter and an adjustable shielding device. The fixed lead window comprises a fixed bracket and a rounded rectangular lead window, and a rectangular opening is formed in the lead window; the aperture adjusting part comprises a base and a pressing ring, an annular groove is formed in the base, a rotatable rotating disc is arranged in the annular groove, the pressing ring is used for abutting the rotating disc into the annular groove, a plurality of radial sliding grooves are formed in the rotating disc, and a plurality of shielding blades stacked layer by layer are arranged between the rotating disc and the base. The upper ends and the lower ends of the shielding blades are hinged to the rotating disc and the base through upper pin shafts and lower pin shafts respectively, the upper pin shafts are slidably installed in the radial sliding grooves, the rotating disc is rotated so that the upper pin shafts can slide in the radial sliding grooves in the direction close to or away from the center of the rotating disc, and the upper ends of the shielding blades are driven to be close to or away from each other. The shielding range of the shielding blade is adjusted; the shielding efficiency, the shielding utilization rate and the imaging quality of the beam limiting device are improved.

The utility model discloses a flexible combination cable for a mobile system, which comprises two signal core wires and two control core wires, the signal core wires and the control core wires are twisted into a cable, the center and the outer side of the cable are filled with filling ropes, the signal core wires and the control core wires of the cable are wrapped by a wrapping tape, and a sheath is extruded on the wrapping tape; each signal core wire comprises a signal conductor, the signal conductor is formed by twisting a plurality of Category 6 + copper wires of phi 0.05 mm, a signal insulating layer is extruded on the signal conductor, a winding shielding layer is wound on the signal insulating layer, and the winding directions of the winding shielding layers in the two signal units are opposite; the control core wire comprises a control conductor, the control conductor is formed by twisting a plurality of Category 6 + copper wires of phi 0.05 mm, and a control insulating layer is extruded on the control conductor; the twisting direction of the signal conductors, the twisting direction of the control conductors and the twisting direction during cabling are consistent. The flexible cable is not only good in flexibility, but also excellent in electrical performance.

A zirconium hydride-based moderation shielding material containing gadolinium oxide / samarium oxide / europium oxide, its preparation method, and its application belong to the field of radiation shielding technology. It solves the problems of hydrogen loss, cracking, and poor thermal stability inherent in existing zirconium hydride materials. The material of this invention has a density of 5.58–5.71 g / cm³. 3 The hydrogen content is 1.6wt%~1.83wt%. The mass proportions of each substance in the total amount of ZrH2, Gd2O3, Sm2O3 and Eu2O3 are: 99%≤ZrH2<100%, 0%≤Gd2O3≤1%, 0%≤Sm2O3≤1%, 0%≤Eu2O3≤1%, 0%<Gd2O3+Sm2O3+Eu2O3≤1%. The hydrogen release initiation temperature is ≥557℃. Utilizing multi-element synergistic absorption, the shielding efficiency for 1MeV fast neutrons is ≥97.5%, and the thermal neutron proportion is reduced by ≥80%. It is suitable for small nuclear power reactors below 600℃.