公开(公告)号：DE2755091A1

公开(公告)日：1978-07-06

申请号：DE2755091

申请日：1977-12-10

Applicant: IBM

Inventor： HOFER DONALD CLIFFORD ,  KAHWATY VINCENT NOEL ,  VALENTINO CARL ROBERT

IPC: G01N24/08 ,  G01R33/46 ,  G01N27/78

Abstract: A method is described for the quantitative analysis of a solution in which the solvent produces a nuclear magnetic resonant (NMR) spectral peak that dominates the system. A first spectrum containing the peak is made by operation of a nuclear magnetic resonant spectrometer at a first gain setting. The NMR apparatus is a pulse-modulated, Fourier-transform type spectrometer. A second spectrum is produced in which a 180 DEG pulse is applied to invert the spectral component magnetization followed after a period of time by a 90 DEG pulse. The period of time is sufficient to allow the solvent or component producing the unwanted peak to relax from the inverted state to a point where there is minimum magnetization along the longitudinal axis. At this point, in many solutions the other components have completely relaxed so that the 90 DEG pulse produces a free induction decay signal which, after undergoing the Fourier-transformation, yields a spectrum that does not include any significant peak due to the solvent. Thereafter, the quantitative analysis is performed by measuring the areas under the respective component peaks and simultaneously solving a series of equations in which the weight of the various components is proportional to the respective areas under the peaks and to the gain settings of the spectrometer.

公开(公告)号：DE69616645D1

公开(公告)日：2001-12-13

申请号：DE69616645

申请日：1996-04-22

Applicant: IBM

Inventor： ABOAF JOSEPH ADAM ,  DENISON EDWARD VIRGIL ,  FRIEDMAN JULES DAVID ,  KAHWATY VINCENT NOEL ,  KLUGE II

IPC: G11B5/11 ,  G11B5/17 ,  G11B5/31 ,  G11B5/39 ,  G11B5/40 ,  G11B5/255

Abstract: A head (10) is provided for reading and writing to tape media (48) along a tape head face. The tape head comprises a plurality of modules, each module comprising a read element (54) and a write element (52) spaced apart and terminating at the tape head face and formed over a substrate (12). The read element comprises a soft film bias layer (24) and a hard film bias layer (25) butted against the SFB layer. The write element comprises two pole tips (14,16) spaced apart by a gap (22). The tape head further includes a plurality of activating conducting coil turns (20) operatively associated with the write element and covered by a cross-linked photoresist and positioned between the gap and one of the pole tips and set back from the tape head face. The tape head has at least one of the following elements: (a) a wear shield (34) between the read element and the write element for limiting wear of the gap between the two pole tips, the wear shield being grounded for decoupling read and write functions of the tape head, for allowing same module read/servo/write functions simultaneously, and for grounding static charge from the tape media; (b) a layer of electrically conductive and corrosion-resistant material (62), such as rhodium, under the hard film bias layer to reduce its resistance; and (c) a non-activating dummy coil turn (120,220) closer to the pole tips than the activating coil turns for defining a forward termination of the cross-linked photoresist (38a) between the activating coil turns and the tape head face to thereby provide improved ease of processability.

公开(公告)号：DE69213558T2

公开(公告)日：1997-03-13

申请号：DE69213558

申请日：1992-04-30

Applicant: IBM

Inventor： ABOAF JOSEPH ADAM ,  DENISON EDWARD BIRGIL ,  KAHWATY VINCENT NOEL ,  STEVING GERALD

IPC: G11B5/31 ,  G11B5/39

Abstract: An interleaved bi-directional magnetic tape head for contact recording has a stripe poletip 30 in the form of a thin film of a soft magnetic material deposited onto a magnetic ferrite substrate 22. A second thin film polepiece 40 is deposited over a gap region 26. A closure block 24 of a non-magnetic ceramic encloses the layers together with leveling insulation layers 32, 34 and deposited activating conductor turns 36. The stripe poletip extends for a distance just short of the first conductor turn and provides a balancing of the saturation moment of the pole pieces and provides for better recording capability, especially when operating in a trailing magnetic ferrite mode.

公开(公告)号：DE69012479D1

公开(公告)日：1994-10-20

申请号：DE69012479

申请日：1990-05-21

Applicant: IBM

Inventor： ABOAF JOSEPH ADAM ,  KAHWATY VINCENT NOEL ,  NIX JAMES LAMAR ,  SHELLEDY FRANK BOYD

IPC: G01R33/09 ,  G11B5/39 ,  H01L43/08 ,  G11B5/37

Abstract: A soft film biased magnetoresistive sensor (10) is fabricated to have reduced Barkhausen noise. The magnetic ratio of the film layers (14 and 18) is controlled to be in the range of 1.7 to 1.95 and the optimum bias point is controlled to be in the range of 35 and 41 degrees.