Abstract: A magnetic test module runs on a spin stand to detect amplitude decay and noise evolution at the same time. Signal-to-noise ratio (SNR) decay is directly measured. The recording performance is correlated better with SNR instead of signal only. The thermal stability of the system is evaluated more accurately with this SNR decay method. A heater is placed under the media disk, and a remote sensing thermometer and temperature controller form a subsystem to set up desired environmental temperature. The heater creates a heated band and the read/write head flies above the heated band. The temperature control system may be removed when SNR decay measurement is performed under room temperature.

Abstract: A method for determining whether a spike in a read back signal from a read head positioned over a perpendicular recording disk having a magnetically soft underlayer (SUL) is caused by a defect in the SUL or by a thermal asperity (TA). A first read back signal with the spike is obtained in the absence of a local magnetic field near the read head. Then, a permanent magnet or electromagnet is used to induce a small local magnetic field by the read head, and a second signal is obtained. If the signals are substantially similar, a thermal asperity is indicated. Otherwise a defect in the 13 magnetically soft underlayer of the disk is indicated.

Abstract: Several compositions for use as structural adhesives are disclosed. The compositions include a monomer component and a catalyst component. In one aspect, the monomer component includes a first elastomeric material of a block copolymer of styrene and isoprene, a second elastomeric material of a block copolymer of styrene and butadiene, and a cross-linked rubber of a copolymer of acrylonitrile and butadiene. In a second aspect, the monomer component includes a first elastomeric material of a block copolymer of styrene and butadiene, and a cross-linked rubber of a copolymer of acrylonitrile and butadiene. In another aspect, isophthalic acid is utilized as a polymerizable acid monomer in combination with a phosphate ester. In another aspect, the monomer component includes a cohesive failure mode promoter of rosin esters or of talc.

Abstract: Several compositions for use as structural adhesives are disclosed. The compositions include a monomer component and a catalyst component. In one aspect, the monomer component includes a first elastomeric material of a block copolymer of styrene and isoprene, a second elastomeric material of a block copolymer of styrene and butadiene, and a cross-linked rubber of a copolymer of acrylonitrile and butadiene. In a second aspect, the monomer component includes a first elastomeric material of a block copolymer of styrene and butadiene, and a cross-linked rubber of a copolymer of acrylonitrile and butadiene. In another aspect, isophthalic acid is utilized as a polymerizable acid monomer in combination with a phosphate ester. In another aspect, the monomer component includes a cohesive failure mode promoter of rosin esters or of talc.

Abstract: A joint seal has a through bore and two spherical spaced convex surfaces which mate with respective concave spherical surfaces on a pair of adjacent flanges. The flanges are welded to and about the periphery of corresponding spaced pipes one of which is inserted in the bore of the seal. The flanges are joined by two bolts, one flange being fixedly secured to the bolts and the other resiliently movably secured to the bolts by a pair of springs to permit that other flange to rotate in response to rotation of the pipe affixed thereto. The one flange forms a static wedge-like seal joint with one of the pipes and the other flange a dynamic seal joint with the respective seal spherical surfaces, the spherical seal and flange surfaces being urged together in wedged relation by the springs.