Abstract: The Invention provides practical apparatus and methods for significant improvements to conventional radiography practice. It can image objects having negligible x-ray absorption contrast e.g. otherwise x-ray transparent low-Z artifacts such as human soft-tissue, by obtaining edge-enhanced contrast from an object's (BDY) x-ray refractive-index gradients. In mammography, the contrast of small micro-calcifications is increased typically 4-fold, or more. It can be "tuned" to obtain element-selective refractive-index enhanced contrast to resonantly image minute quantities of a specific element with Z.apprxeq.35-56 and only that element. With only a single brief x-ray exposure it can produce two independent images, e.g. of the object's x-ray absorption and refractive-index distributions. It virtually eliminates the blurring and contrast reducing effects of x-ray scatter, especially of very small-angle scatter.

Abstract: The invention is a neutral atom (and/or molecule) matter-wave interferometer (and/or set of interferometers) that can be used as an inertial sensor with a sensitivity exceeding that of conventional mechanical sensors and multiple circuit optical interferometers (including ring lasers) by many powers of ten. An interferometer in which matter-wave propagation beam paths enclose a finite area will sense rotations via the Sagnac effect. One with the paths displaced from each other will sense acceleration plus gravity. Interferometers with paths that follow a figure-eight pattern yield a gravitational gradiometer. Laser cooling and slowing of a beam of neutral atoms provides a low energy nearly monochromatic source. Diffraction gratings are employed as beam splitters. Such gratings may consist of apertures in a sheet of solid material, near-resonant standing-wave laser beams, or crystal faces.

Abstract: The invention is a neutral atom (and/or molecule) matter-wave interferometer (and/or set of interferometers) that can be used as an inertial sensor with a sensitivity exceeding that of conventional mechanical sensors and multiple circuit optical interferometers (including ring lasers) by many powers of ten. An interferometer in which matter-wave propagation beam paths enclose a finite area will sense rotations via the Sagnac effect. One with the paths displaced from each other will sense acceleration plus gravity. The matter-wave energy and mass dependence of the phase shifts that are due to rotation and acceleration are different. Thus a pair of interferometers with different energies and/or masses can perform simultaneous independent measurements of rotation and acceleration. Interferometers with paths that follow a figure-eight pattern yield a gravitational gradiometer. Laser cooling and slowing of a beam of neutral atoms provides a low energy nearly monochromatic source.

Abstract: To prevent crossflow of wind and increase aerodynamic efficiency of boom-footed sail, a stationary sealing vertical baffle structure is mounted along the centerline of a sailboat under the boom. The top portion of the baffle is made of a compliant sealing material, e.g., closed cell polyurethane foam, which forms a tight seal with the boom when the boom is positioned substantially along the centerline, as is common when sailing to weather. The boom and baffle can have curved side surfaces which form with the sail a substantially continuous surface which extends the effective sail area down to the deck.

Abstract: To prevent crossflow of wind and increase aerodynamic efficiency of a boom-footed sail, a stationary structure which forms a compliant sliding seal with the boom, in particular a vertical baffle structure, is mounted along the centerline of a sailboat under the boom. The top portion of the baffle is made of a compliant sealing material, e.g., closed cell polyurethane foam, which forms a tight seal with the boom when the boom is positioned substantially along the centerline, as is common when sailing to weather, and over a range of vertical and horizontal motion of the boom. The boom and baffle can have curved side surfaces which form with the sail a substantially continuous surface which extends the effective sail area down to the deck.