135results about How to "Good electromagnetic properties" patented technology

A magnetic recording medium includes, in the following order: a backcoat layer; a nonmagnetic support; a nonmagnetic layer containing a nonmagnetic powder and a binder; and a magnetic layer containing a ferromagnetic powder and a binder, wherein the backcoat layer contains particles having an average primary particle size D50 of from 0.05 to 1.0 μm and forming substantially no aggregates nor agglomerates in the backcoat layer.

The magnetic tape has a magnetic layer and a backcoat layer, wherein, each of the magnetic layer and backcoat layer contains a fatty acid ester, the Ra measured on the magnetic layer side surface is less than or equal to 2.8 nm, the difference between the spacing measured by optical interferometry on the magnetic layer side surface after and before vacuum heating is greater than 0 nm but less than or equal to 8.0 nm, the FWHMbefore on the backcoat layer side surface is greater than 0 nm but less than or equal to 10.0 nm, the FWHMafter on the backcoat layer side surface is greater than 0 nm but less than or equal to 10.0 nm; and the difference between the spacing measured on the backcoat layer side surface after and before vacuum heating is greater than 0 nm but less than or equal to 8.0 nm.

The magnetic tape has a magnetic layer containing ferromagnetic powder, abrasive, and binder on a nonmagnetic support, wherein the centerline average surface roughness Ra measured on the surface of the magnetic layer is less than or equal to 1.8 nm, the contact angle for 1-bromonaphthalene that is measured on the surface of the magnetic layer falls within a range of 45.0° to 60.0°, and the coefficient of friction that is measured on the base portion of the surface of the magnetic layer is less than or equal to 0.35.

The magnetic tape has a magnetic layer containing ferromagnetic powder and binder on a nonmagnetic support, wherein the centerline average surface roughness Ra as measured on the surface on the magnetic layer side of the magnetic tape is less than or equal to 1.8 nm, and the logarithmic decrement as determined by a pendulum viscoelasticity test on the surface on the magnetic layer side of the magnetic tape is less than or equal to 0.050.

The magnetic tape has a magnetic layer containing ferromagnetic powder and binder on a nonmagnetic support, wherein the centerline average surface roughness Ra as measured on the surface on the magnetic layer side of the magnetic tape is less than or equal to 1.8 nm, and the logarithmic decrement as determined by a pendulum viscoelasticity test on the surface on the magnetic layer side of the magnetic tape is less than or equal to 0.050.

The present invention relates to a magnetic recording medium comprising a nonmagnetic layer comprising a nonmagnetic powder and a binder and a magnetic layer comprising a ferromagnetic powder and a binder in this order on a nonmagnetic support. The magnetic layer has a thickness ranging from 30 to 130 nm, and a glossiness of the magnetic layer surface ranges from 155 to 270 percent.

A magnetic recording medium is disclosed, which comprises a support having thereon a magnetic layer comprising a binder and a ferromagnetic powder dispersed therein, wherein said binder comprises a polyurethane resin having at least one cyclic hydrocarbon group and at least one ether linkage, and said ferromagnetic powder is a ferromagnetic metallic powder which comprises Fe and has a mean major-axis length of from 0.05 to 0.19 .mu.m and a crystallite size of from 100 to 230 .ANG.; and further a magnetic recording medium is disclosed, comprising a support having thereon in succession an undercoat layer comprising a binder U and an inorganic powder dispersed therein and a magnetic layer comprising a binder M and a ferromagnetic powder dispersed therein, wherein at least either of the binder U or M comprises a polyurethane resin having at least one cyclic hydrocarbon group and at least one ether linkage and said ferromagnetic powder is a ferromagnetic metallic powder which comprises Fe and has a mean major-axis length of from 0.05 to 0.19 .mu.m and a crystallite size of from 100 to 230 .ANG..

The invention relates to a nested type Koch fractal Beidou dual-frequency micro-strip antenna which comprises a high dielectric constant dielectric substrate, a good conductor grounding reflection plate and an N type or sma national standard joint, a structural mode of copper axis feed is adopted, metal good conductors are coated on two faces of the high dielectric constant dielectric substrate, a nested type ring outer Koch fractal paster and a nested type ring inner Koch fractal paster are arranged on the upper surface of the high dielectric constant dielectric substrate, and a gap groove structure is arranged between the ring outer Koch fractal paster and the ring inner Koch fractal paster. A low-frequency stage feed hole is formed in the ring outer Koch fractal paster, a high-frequency stage feed hole is formed in the ring inner Koch fractal paster, and four gap grooves are formed in the good conductor grounding reflection plate. The nested type Koch fractal Beidou dual-frequency micro-strip antenna has the advantages of being novel in structure, small in size, good in radiation characteristic, small in effect of environment factor, low in cost, easy to integrate and the like, and can meet the requirement of a Beidou satellite communication system for an antenna.

The magnetic tape has a magnetic layer containing ferromagnetic powder and binder on a nonmagnetic support, wherein a timing based servo pattern is present on the magnetic layer, the centerline average surface roughness Ra that is measured on the surface of the magnetic layer is less than or equal to 1.8 nm, and the coefficient of friction that is measured on the base portion of the surface of the magnetic layer is less than or equal to 0.35.

The invention discloses a double-frame and notched four-bridge bridging microstrip antenna applied to a compass system, and relates to a microstrip patch antenna. The double-frame and notched four-bridge bridging microstrip antenna applied to the compass system is low in return loss, high in gain, small in interference, high in symmetrical characteristic, high in integration density and small in size, has a directed radiation characteristic and is compatible with a compass frequency range satellite positioning system. The double-frame and notched four-bridge bridging microstrip antenna comprises a base plate. Metal layers are coated on the two surfaces of the base plate, wherein one metal layer on one surface is machined to an outer frame and double frames of an internal radiation paster, wherein the outer frame is provided with cut corners, rectangular notches are arranged on the inner edge of the outer frame, and a symmetrical structure of the inner radiation paster and an external radiation paster is formed by a four-bridge bridging manner inside and outside. The other metal layer on the other surface is an earth plate. Further miniaturization of the antenna is achieved, and requirements of a compass satellite communication system can be well met by using of the notched four-bridge bridging microstrip patch antenna structure and applying of a distribution loading technique to a radiation element and through comprehensive optimization of serial technologies.

Provided is a magnetic recording medium having excellent surface smoothness and coating durability. The magnetic recording medium comprises an undercoating layer comprising a radiation-curing resin as a main component and a magnetic layer comprising a ferromagnetic powder and a binder in this order on a nonmagnetic support. The undercoating layer comprises no particulate matter, and the magnetic layer comprises a diamond powder.

The invention discloses a sendust magnetic powder core. Magnetic powder adopted for the sendust magnetic powder core comprises, by weight, 9-10% of Si, 5-6% of Al, and the balance Fe. Based on the ratio, the sendust magnetic powder core is prepared through powder pre-annealing, screening, passivation, insulation coating, compression moulding forming and heat treatment. According to the sendust magnetic powder core, the sendust magnetic powder core preparing technology is optimized, each preparation step is controlled, and excellent comprehensive performance is realized through the cooperation of all the steps.

The present invention relates to a magnetic recording medium comprising a magnetic layer comprising a hexagonal ferrite powder and a binder on one surface of a nonmagnetic support and a backcoat layer on the other surface of the nonmagnetic support. A power spectrum density at a pitch of 10 micrometers ranges from 800 to 10,000 nm3 on the magnetic layer surface, a power spectrum density at a pitch of 10 micrometers ranges from 20,000 to 80,000 nm3 on the backcoat layer surface, the magnetic layer has a center surface average surface roughness Ra, as measured by an atomic force microscope, ranging from 0.5 to 2.5 nm, and the hexagonal ferrite powder has an average plate diameter ranging from 10 to 40 nm.

The invention discloses a quadruple spiral distribution loading oscillator microstrip antenna applied to a Beidou system and relates to a microstrip patch antenna. The quadruple spiral distribution loading oscillator microstrip antenna applied to the Beidou system is low in echo loss, low in interference, high in gain, high in symmetry, high in integration level and miniature and has the directed radiation characteristics. The quadruple spiral distribution loading oscillator microstrip antenna applied to the Beidou system is provided with a substrate, wherein copper is coated on two sides of the substrate; the upper surface of the substrate is provided with a quadruple spiral oscillator arm structure; the sides of the quadruple spiral oscillator arm structure form a spiral oscillator in a rewinding form; a loading hole and a feed hole are formed in the spiral oscillator; the quadruple spiral oscillator arm structure is rewound by 720 degrees towards the center of each side; the lower surface of the substrate is provided with a grounding plate; the grounding plate is connected with an outer core of a feed copper axis; and the loading hole is connected with an inner core of the feed copper axis.

Disclosed is a magnetic recording medium comprising a magnetic layer on a surface of a flexible support and a backcoat layer on the opposite surface, characterized in that the backcoat layer comprises a granulated oxide consisting of titanium oxide, alpha-iron oxide or a mixture thereof and carbon black in the weight ratio ranging from 60 / 40 to 90 / 10, and further comprises a binder in an amount ranging from 10 to 40 parts by weight with respect to 100 parts by weight of the total amount of the granulated oxide and carbon black. The magnetic recording medium of the present invention is characterized in that both the running durability and electromagnetic characteristics are excellent.

The soft magnetic structural steel plate with excellent welding performance has very low C content, Si content of 1.45-1.65 wt%, medium Mn content, alloyed Ni and Cr, Ti content of 0.008-0.016 wt%, N content controlled to be lower than 0.0055 wt%, Ca or RE treatment, and optimized rolling and post-treatment process. It has excellent mechanical performance, good electromagnetic performance, excellent welding performance, excellent low temperature impact toughness, and capacity of being used in cold area.

The present invention relates to soft magnetic structural steel, and is especially one kind of soft magnetic structural steel resisting salt fog and its making process. The present invention solves the technological problem of raising the salt fog corrosion resistance of soft magnetic structural steel. The soft magnetic structural steel consists of C 0.020-0.040 wt%, Si 1.40-1.60 wt%, Mn 0.40-0.80 wt%, P not more than 0.015 wt%, S not more than 0.005 wt%, Als 0.040-0.060 wt%, Cu 0.20-0.50 wt%, Ti 0.035-0.055 wt%, N not more than 0.0035 wt%, Ni 0.80- 1.20 wt%, and Ca or REM 10-60ppm, except Fe and inevitable impurities. Its making process includes continuous casting, re-crystallization controlling rolling, accelerated cooling or intermittent direct quenching, and subsequent slow cooling step. The present invention is especially suitable for use as side guide plate in magnetic suspension train track beam in high salt fog area.

The present invention provides a magnetic recording medium comprising an undercoating layer comprising a radiation-curable compound that has been cured by irradiation with radiation, a nonmagnetic layer comprising a nonmagnetic powder and a binder, and a magnetic layer comprising a ferromagnetic powder and a binder in this order on a nonmagnetic support, wherein the magnetic layer and / or the nonmagnetic layer comprise a carbonic ester denoted by general formula (1), and the undercoating layer has an indentation hardness lower than that of the nonmagnetic support.In general formula (1), each of R1 and R2 independently denotes a saturated hydrocarbon group, with a total number of carbon atoms in R1 and R2 being equal to or higher than 12 but equal to or lower than 50.

A magnetic recording medium comprising a magnetic layer, a support and a backing layer in this order, wherein the backing layer comprises a binder and an inorganic powder having a surface covered with an electrically conductive substance.

The invention discloses a slice omnidirectional broadband surface conformal antenna, which is formed by an antenna (1), a coaxial feeding joint (3), an A resistance (4) and a B resistance (5), wherein the structure of the A resistance (4) is same with the structure of the B resistance (5), the sensitive end of a probe (35) in the coaxial feeding joint (3) is welded on the feeding end (1a) of the bottom end of the antenna (1), the coaxial feeding joint (3) is mounted on the lower plate surface (2b) of a mounting plate (2), the A resistance (4) is mounted between the bottom of a right antenna wing (12) of the antenna (1) and the upper plate surface (2a) of the mounting plate (2), and the B resistance (5) is mounted between the bottom of a left antenna wing (13) of the antenna (1) and the upper plate surface (2a) of the mounting plate (2). The slice omnidirectional broadband surface conformal antenna simultaneously adopts bottom-end two-side resistance loading and a bottom-end conical gradation structures which lead the band width of the slice omnidirectional broadband surface conformal antenna to be widened. Compared with the bowed antennas which are used at present, the surface conformal antenna with a slice structure can reduce the negative influence to platform pneumatic property, the installation position is flexible, and a place which is convenient for antennas to play efficiency is chosen to mount.

Provided is a magnetic recording medium having excellent dispersibility, smoothness and electromagnetic characteristics. The magnetic recording medium comprises at least one magnetic layer comprising a ferromagnetic powder and a binder on a nonmagnetic support. Said ferromagnetic powder is a ferromagnetic metal powder having an average major axis length of 10 to 80 nm and a crystallite size of 8 to 18 nm, or a ferromagnetic hexagonal ferrite powder having an average plate diameter of 5 to 40 nm, and said binder comprises 0.2 to 0.7 meq / g of at least one polar group selected from —SO3M, —OSO3M, —PO(OM)2, —OPO(OM)2 and —COOM (where M denotes a hydrogen atom, alkali metal or ammonium salt), and / or 0.5 to 5 meq / g of at least one polar group selected from —CONR1R2, —NR1R2 and —NR1R2R3+ (where R1, R2 and R3 independently denote hydrogen atoms or alkyl groups).

A method for producing a cage rotor for an asynchronous machine is provided. The method includes providing a rotor body having a conductor bar segment in which conductor bars are provided, producing conductor bar slots in the conductor bar segment, wherein one conductor bar slot is provided for each of the conductor bars and producing short circuit ring recesses for short circuit rings, wherein the conductor bar slots each open into the short circuit ring recesses, pressure die casting cage material in the conductor bar slots, in situ, so that the conductor bars are formed of the conductor bar material in the conductor bar slots and the short circuit rings are formed in the short circuit ring recesses, and generating an area in the conductor bar material and the rotor body material including a metallurgical bond between the conductor bar material and the rotor body material at interfaces between the conductor bars and the rotor body.

The invention provides a preparation method of core-shell magnetic microspheres, and belongs to the technical field of functional material preparation. The preparation method comprises the steps thatfirstly, monodispersed phenolic aldehyde microspheres or monodispersed silicon dioxide phenolic aldehyde core-shell microspheres are synthesized; then the microspheres and ferric salts are dispersed in a mixing solvent containing glycerinum and isopropanol, added into a hydrothermal reaction still for an airtight high-pressure solvothermal reaction, and a phenolic aldehyde microsphere / glycerinum ferric core-shell structure product or a silicon dioxide / phenolic aldehyde / glycerinum ferric core double-shell structure product are correspondingly obtained; and finally, the phenolic aldehyde microsphere / glycerinum ferric core-shell structure product is calcined in an inert atmosphere in a tube furnace to form carbon / ferroferric oxide core-shell magnetic microspheres, and the silicon dioxide / phenolic aldehyde / glycerinum ferric core double-shell structure product is subjected to high-temperature calcination and alkali etching by inert gas to obtain hollow carbon / ferroferric oxide double-shellmicrospheres. The preparation method is simple, magnetic nanosheets and carbon are compounded successfully, the electromagnetic property of the magnetic nanosheets is improved, the nanosheets adoptedon an outer layer can effectively inhibit a skin effect, the prepared products have the excellent electromagnetic property, and the preparation method of the core-shell magnetic microspheres can be used for electromagnetic wave absorption and shielding fields.

This invention discloses an antenna of a book electronic certificate read-write device composed of an upper antenna conductor loop, an upper antenna conductor loop, an impedance match network connected with them, a RF connector connected with the impedance match network, a lower antenna base board and an upper antenna base board, in which, a metal antenna coil starts from the RF connector to circle around one or many times to come back to the connector again, and the impedance match network part is composed of resistors and capacitors, which can read non-contacted IC chips of multiple regions in certificates at the same time and avoids interference among antennas.

The invention provides a better electromagnetic wave lens, a production method and a lens antenna. The electromagnetic wave lens is a rolled body formed by rolling a strip-shaped material; dielectric constants of a dielectric materials are gradually changed in the transverse direction and the longitudinal direction of the strip-shaped material; after the strip-shaped material is rolled into the rolled body, the dielectric material is distributed in at least one predetermined three-dimensional space range in the rolled body, and the rolled body is called a lens body; the part, except the lens body, of the rolled body is called as a non-lens part; the dielectric constant in the lens body is not lower than that of the non-lens part; in the lens body, dielectric constants in all directions from inside to outside are lower and lower, and the directions from inside to outside refer to the direction from the central area of the lens body to the boundary of the lens body. The invention has the advantages of good electromagnetic property, high product consistency, high production efficiency, suitability for wide target sizes, compact and stable structure, and realization of single entity and multiple lenses.

The invention discloses an all-directional wideband antenna which has the same shape with an installation surface structure; the all-directional wideband antenna comprises a coaxial feed joint, a cylindrical back chamber (1), a glass fiber reinforced plastic cover (2), a metal upper cover (3), a metal lower cover (7), a sleeve (8), three groups of short circuit columns and three supporting frames; three groups of short circuit columns are arranged between the metal upper cover (3) and the metal lower cover (7); the three supporting frames are arranged on the internal wall of the sleeve (8) which is welded inside the cylindrical back chamber (1) and is positioned at the jointing of a conical bottom surface (101) and a transition section (103); the glass fiber reinforced plastic cover (2) is arranged on a flange platform (104) of the cylindrical back chamber (1); the frontal disc (35) of the metal upper cover (3) is attached to the glass fiber reinforced plastic cover (2); the frontal disc (35) of the metal upper cover (3) is attached to the glass fiber reinforced plastic cover (2), thus leading the all-directional wideband antenna to be internally embedded into the installation plane of a movable platform so as to form the structural conformality.