Patents by Inventor Stephen H. Smallcombe

Stephen H. Smallcombe has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Accelerating NMR sample thermal equilibration by RF heating
    Patent number: 6218835
    Abstract: Radio-frequency (RF) heating is used to accelerate the thermal equilibration of dielectrically lossy nuclear magnetic resonance (NMR) samples. High-power heating RF pulses are applied to the sample before lower-power measurement RF pulses, using any of the NMR probe coils. The heating pulses are offset in frequency relative to the measurement pulses, such that the heating pulses do not magnetically affect the spins of interest. Heating pulse sequences of decreasing power can be used to prevent the sample temperature from overshooting the desired equilibrium temperature. Heating RF pulses can pre-establish the thermal effects of both measurement-independent and measurement-dependent heating. For pre-establishing the thermal effects of measurement-dependent heating, the heating pulse transients are chosen to be proportional to subsequent measurement pulse transients.
    Type: Grant
    Filed: August 2, 1999
    Date of Patent: April 17, 2001
    Assignee: Varian, Inc.
    Inventor: Stephen H. Smallcombe
  • Time correction for digital filters in transient measurments
    Patent number: 5867410
    Abstract: Observation of transient phenomena in an oversampled regime is implemented with a time correction obtained by prepending one or more pseudo datums to the oversampled data to constitute an effective negative delay for the oversampled data set including the pseudo datums. For an oversampling factor N and oversampling rate .omega..sub.s, a digital filter furnishes downsampled data uniformly spaced in time by N/.omega..sub.s and positioned at n (N/.omega..sub.s) where n is the discrete downsampled time coordinate.
    Type: Grant
    Filed: September 27, 1996
    Date of Patent: February 2, 1999
    Assignee: Varian Associates, Inc.
    Inventors: Stephen H. Smallcombe, Steven L. Patt
  • Solvent suppression method for LC-NMR and high-resolution-NMR
    Patent number: 5847564
    Abstract: Improved solvent suppression in NMR data is achieved using pulse sequences wherein each of a series of selective excitation pulses are followed by a magnetic gradient pulse and a delay, where the magnetic gradient pulse amplitudes monotonically decrease by a selected fraction of the preceeding gradient pulse. Decoupling a second nucleus during selective excitation pulses has been shown to be efficacious for suppression of organic solvents.
    Type: Grant
    Filed: December 23, 1996
    Date of Patent: December 8, 1998
    Assignee: Varian Associates, Inc.
    Inventors: Stephen H. Smallcombe, Steven L. Patt, Paul A. Keifer
  • Method and apparatus for NMR sample tube vortex plug
    Patent number: 4077002
    Abstract: A vortex restraining plug for an NMR spinning sample tube which floats partially submerged in the sample and which restrains vortexing.
    Type: Grant
    Filed: November 22, 1976
    Date of Patent: February 28, 1978
    Assignee: Varian Associates, Inc.
    Inventors: Barbara L. Erwine, Stephen H. Smallcombe
  • Analytical instrument optimum data acquisition method and apparatus
    Patent number: 4070708
    Abstract: An analytical instrument employing ensemble averaging to improve the signal-to-noise ratio including means for determining the most efficient scaling factor and for controlling the instrument to maintain assurance of efficient averaging.
    Type: Grant
    Filed: September 1, 1976
    Date of Patent: January 24, 1978
    Assignee: Varian Associates, Inc.
    Inventors: Stephen H. Smallcombe, Howard D. W. Hill