277 results about "Transverse magnetic field" patented technology

This invention features a combined radio frequency (RF) and Hall Effect ion source and plasma accelerator system including a plasma accelerator having an anode and a discharge zone, the plasma accelerator for providing plasma discharge. A gas distributor introduces a gas into the plasma accelerator. A cathode emits electrons attracted to the anode for ionizing the gas and neutralizing ion flux emitted from the plasma accelerator. An electrical circuit coupled between the anode and the cathode having a DC power source provides DC voltage. A magnetic circuit structure including a magnetic field source establishes a transverse magnetic field in the plasma accelerator that creates an impedance to the flow of the electrons toward the anode to enhance ionization of the gas to create plasma and which in combination with the electric circuit establishes an axial electric field in the plasma accelerator. An RF power source provides RF power to at least one electrode disposed about and / or inside the plasma accelerator that induces current for ionizing the gas to create the plasma such that the axial electric field accelerates ions through the plasma accelerator to provide ion flux.

A permanent magnet in which the magnetization direction varies with location to optimize or restrict a magnetic field property in a selected direction at a selected point. The magnetic field property may be, for example, the transverse magnetic field, axial magnetic field, axial gradient of the transverse magnetic field, transverse gradient of the transverse magnetic field, axis gradient of the axial magnetic field, transverse gradient of the axial magnetic field, the product of the transverse magnetic field and the transverse gradient of the transverse magnetic field, the product of the transverse magnetic field and the axial gradient of the transverse magnetic field, the product of the axial magnetic field and the transverse gradient of the axial magnetic field, or the product of the axial magnetic field and the axial gradient of the axial magnetic field. The magnet may be formed of one or more segments in which the magnetization direction varies smoothly and continuously, or the magnet may be formed of a plurality of segments in which the magnetization direction is constant. A method of making and using such magnets is also disclosed.

A measurement-while-drilling or logging while drilling method and apparatus for determining the azimuth of providing magnetic field in a remote formation layer in the vicinity of a down hole resistivity tool. A cross-component magnetic field with substantially orthogonal transmitter and receiver coils is provided. The coil planes are either substantially orthogonal (coaxial coils) or parallel (transverse coils) with respect to, the longitudinal axis of the tool body. The coils are placed on the tool body having a external surface and a plurality of grooves are cut in the external surface of the tool body and oriented substantially horizontally with respect to the longitudinal axis of the tool body for the coils and oriented vertically with respect to the longitudinal axis of the tool body for the coaxial coils. A transverse and coaxial coil are placed in the grooves for transmission or reception of a cross-component transverse magnetic field. Ferrite materials may be inserted in the grooves in between the coil wire and the bottom of the grooves. Multiple receivers, transmitters and frequencies may be used to obtain the maximum possible signal-to-noise ratio. The in-phase or quadrature part of a magnetic field, or a combination of the two, or alternatively, the amplitude and / or phase, of the cross-component magnetic field may be measured and processed to indicate the azimuth of a remote layer boundary, provided that the layer boundary is within the depth of investigation of the tool. Measurements may also be made at continuous or multiple tool azimuths.

An apparatus and method of uniformly heating, rheologically softening, and thermoplastically forming metallic glasses rapidly into a net shape using a rapid capacitor discharge forming (RCDF) tool in combination with an electromagnetic force generated by the interaction of the applied current with a transverse magnetic field. The RCDF method utilizes the discharge of electrical energy stored in a capacitor to uniformly and rapidly heat a sample or charge of metallic glass alloy to a predetermined “process temperature” between the glass transition temperature of the amorphous metal and the equilibrium melting point of the alloy in a time scale of several milliseconds or less, at which point the interaction between the electric field and the magnetic field generates a force capable of shaping the heated sample into a high quality amorphous bulk article via any number of techniques including, for example, injection molding, dynamic forging, stamp forging, and blow molding in a time scale of less than one second.

An electric motor, including at least two permanent magnet segments disposed around a motor longitudinal axis, in which each permanent magnet segment has end faces extending in the direction of the motor longitudinal axis and is encompassed by two independent yoke ring segments that have a gap between them parallel to a symmetry plane extending through the motor longitudinal axis and the center of the permanent magnet segments in order to reduce the armature transverse field. In addition to the reduction of the armature transverse field, a weight reduction of the electric motor is also achieved. To this end, in a first region close to the end faces of the permanent magnet segments, the one-piece magnetically conductive yoke is provided with a larger cross section than in a second region close to the symmetry plane extending through the center of the permanent magnet segments. The construction is particularly suited for small electric motors, in particular d.c. motors that are excited by permanent magnets.

The invention discloses a method for measuring atomic transverse relaxation time based on an electron resonance phase frequency analysis. In a strong-background magnetic field with almost neglected residual magnetization in a magnetic shielding barrel, a swept-frequency signal that has a bandwidth covering a resonance curve and has an amplitude enabling the resonance curve to have a clear curve under low polarizability is applied in a horizontal direction; an optical swing angle signal of a magnetometer is detected and a spectral analysis is carried out on an outputted signal in a polar coordinate system to obtain a phase frequency response function of the magnetometer; the phase frequency response function is fitted to a corresponding theoretical phase frequency curve of the magnetometer to obtain atomic spinning transverse relaxation time. Because the phase angle is a result obtained by quotient processing of a spinning transverse component, the influence of common coefficient fluctuation is suppressed, so that the phase frequency signal expression is more stable by being compared with amplitude-frequency signal expression. Besides, the theoretical phase frequency curve is not affected by the magnetic induction intensity of the transverse magnetic field and the atomic spinning longitudinal relaxation time, so that complexity of data processing can be reduced. Moreover, a lorenz curve widening risk caused by the transverse magnetic field can be eliminated.

A current perpendicular to plane (CPP) differential giant magnetoresistive (GMR) sensor that is insensitive to stray longitudinal and transverse magnetic fields. The sensor includes an in stack bias layer structure that is used to bias the magnetic moment of first and second free layers disposed at either side thereof. The bias structure includes an antiferromagnetic layer (AFM). An odd number of antiparallel (AP) coupled magnetic layers are formed on a first side of the AFM and an even number of AP coupled magnetic layers on the opposite side of the AFM.

The invention relates to a magnetism transmission gear pair of a novel transverse magnetic field, which can be widely applied to wind power generation, electric cars, ship drive and other industrial transmission fields requiring direct drive. The magnetism transmission gear pair is characterized in that a driving wheel and a driven wheel of the magnetism transmission gear pair are of a flat disk shape, 2pr driving wheel permanent magnets 3 are distributed on the driving wheel, and 2ps driven wheel permanent magnets 7 are distributed on the driven wheel; a ferromagnetic magnetic modulation grid 6 playing a role of modulating an air-gap magnetic field is arranged between the driving wheel and the driven wheel, air gaps are reserved between the ferromagnetic magnetic modulation grid 6 and the end surfaces of the driving wheel and the driven wheel, and the ferromagnetic magnetic modulation grid 6, the driving wheel and the driven wheel have no mechanical contact and are distributed along the same axis; the air-gap magnetic field Bg passes through an air-gap plane along a route parallel to a rotation axis to form a transverse magnetic field of the magnetism transmission gear pair; and during working, power speed change transmission without mechanical contact and friction is realized by utilizing a principle of heteropolarity attraction of an N pole and an S pole of a permanent magnet material.

The present invention relates to a multi-axis magnetic lens for a charged particle beam system. The apparatus eliminates the undesired non-axisymmetric transverse magnetic field components from the magnetic field generated by a common excitation coil and leaves the desired axisymmetric field for focusing each particle beam employed within the system.

The invention discloses a reversed-field permanent-magnet focusing system for multi-beam millimeter wave traveling-wave tubes, which consists of an electron gun end face (1), first magnetic field rectifiers (2), a first peak generation pole shoe (3), a magnetic field reversal pole shoe (4), a second peak generation pole shoe (5), second magnetic field rectifiers (6), a vacuum sealed case (7), a collector end face (8), first permanent magnets (9) and second permanent magnets (10). The reversed-field permanent-magnet focusing system for the multi-beam millimeter wave traveling-wave tubes rectifies magnetic fields on the left and right sides of a magnetic system by the first and second magnetic field rectifiers (2 and 6) so as to reduce a transverse magnetic field without influencing flux rates of electron beams, and simultaneously solves the problem of large volumes of the permanent magnets of a uniform-field permanent-magnet focusing system with large gain due to the applicability of the plurality of first and second permanent magnets (9 and 10) with small volumes to the focusing system.

A silicon single crystal manufacturing method includes: applying a transverse magnetic field to a melt of polysilicon with a carbon concentration of at most 1.0 × 10 15 atoms / cm 3 as a raw material; rotating the crucible at 5.0 rpm or less; allowing inert gas to flow at rate A (m / sec) of formula (1) at a position 20-50% of Y above the melt surface; controlling the rate A within the range of 0.2 to 5, 000 / d (m / sec) (d: crystal diameter (mm)); and reducing the total power of side and bottom heaters by 3 to 30% and the side heater power by 5 to 45% until the solidified fraction reaches 30%. A = Q ‹ 760 1000 ‹ 60 ‹ P ‹ ± / À ‹ X ‹ Y ‹ 10 6 Q: Inert gas volumetric flow rate (L / min) P: Pressure (Torr) in furnace X: Radiation shield opening diameter Y: Distance (mm) from raw material melt surface to radiation shield lower end ± : Correction coefficient

An apparatus and method of uniformly heating, rheologically softening, and thermoplastically forming metallic glasses rapidly into a net shape using a rapid capacitor discharge forming (RCDF) tool in combination with an electromagnetic force generated by the interaction of the applied current with a transverse magnetic field. The RCDF method utilizes the discharge of electrical energy stored in a capacitor to uniformly and rapidly heat a sample or charge of metallic glass alloy to a predetermined “process temperature” between the glass transition temperature of the amorphous metal and the equilibrium melting point of the alloy in a time scale of several milliseconds or less, at which point the interaction between the electric field and the magnetic field generates a force capable of shaping the heated sample into a high quality amorphous bulk article via any number of techniques including, for example, injection molding, dynamic forging, stamp forging, and blow molding in a time scale of less than one second.

A Hall thruster with a shared magnetic structure including a plurality of plasma accelerators each including an anode and a discharge zone for providing plasma discharge. An electrical circuit having one or more cathodes connected to the plurality of plasma accelerators emits electrons that are attracted to the anode in each of the plasma accelerators. A shared magnetic circuit structure establishes a transverse magnetic field in each of the plurality of plasma accelerators that creates an impedance to the flow of electrons toward the anode in each of the plurality of plasma accelerators and enables ionization of a gas moving through one or more of the plurality of plasma accelerators. The impedance localizes an axial electric field in the plurality of plasma accelerators for accelerating ionized gas through the one or more of the plurality of plasma accelerators to create thrust.

The invention discloses an amorphous nanocrystalline magnetic core heat treatment method. The amorphous nanocrystalline magnetic core heat treatment method comprises the steps that (1) a to-be-treatedmagnetic core is placed into a transverse magnetic field heat treatment furnace, and protective gas is led in; (2) heat treatment and magnetic treatment are carried out, wherein in the first stage, the temperature rises to about 300 DEG C from the room temperature, the wasted time is about 60 min, heat preservation is carried out for about 30 min, then the temperature rises to about 400 DEG C, the wasted time is about 30 min, and heat preservation is carried out for about 60 min; in the second stage, the temperature rises to T1 from about 400 DEG C, the wasted time is about 30 min, heat preservation is carried out at T1 for about 210 min, and meanwhile, a transverse magnetic field is applied in the second stage; in the third stage, the magnetic field is removed, meanwhile, the temperaturerises to about 510 DEG C from T1, the wasted time is about 20 min, heat preservation is carried out for about 40 min, then the temperature rises to T2 to be subjected to heat preservation, and the wasted time is about 90 min; and in the fourth stage, heating is stopped, cooling is carried out to the room temperature, wherein the T1 is 460 DEG C-480 DEG C, and the T2 is 560 DEG C-570 DEG C.

The invention discloses a production technology of semiconductor grade silicon single crystal, comprising the following steps: 1, arranging a transverse magnetic field: the magnetic field intensity of the transverse magnetic field is 1300 + / - 100 gausses; 2, preparing silicon material and doping agent; 3, charging; 4, melting material; 5, introducing shoulder and expanding shoulder; 6, rotating shoulder: after the step of expanding shoulder, the step of rotating shoulder is carried out with a casting speed of 3 + / - 0.3 mm / min; and 7, growing at the same diameter: after the step of rotating shoulder, the material grows up to 50 + / - 5 mm with a casting speed of 1.6 + / - 0.1 mm / min; then, a conventional method of growing at the same diameter for direct pulling silicon single crystal is used to complete the subsequent process of growing at the same diameter of the semiconductor grade silicon single crystal. The method has the advantages of reasonable design, simple steps, easiness in realization, easiness in mastering and good using effect, and is capable of effectively guaranteeing the quality of the produced semiconductor grade silicon single crystal. The produced semiconductor grade silicon single crystal has high uniformity of cross-section electric resistivity and no micro-defects such as swirl.

The present invention relates to magnets and to magnetic resonance imaging systems. The magnet is open with magnetic coils arranged in quadrant, separated about two perpendicular planes, a midplane and a plane of reflection, and wherein the windings are configured such that, in operation, current flow is symmetrical about the plane of reflection and anti-symmetrical about the midplane, to produce a nett magnetic field at the center in a direction perpendicular to the plane of reflection.