Abstract: An apparatus and method for increasing subterranean fluid production are disclosed. A downhole stimulation apparatus produces elastic wave energy which propagates into the subterranean strata of nearby fluid fields. The wave energy creates gravity separation of the fluids, altering the phase permeability of subterranean formations and causing the fluid to migrate to wells in the field being stimulated. The stimulation apparatus employs an underground casing which provides a sealed vessel in which is supported a tubing string. The casing and tubing string are filled with a working fluid. A pumping unit reciprocates a plunger within the tubing string to cyclically pressurize and depressurize the working fluid, the depressurization of working fluid creating the elastic wave energy.

Abstract: The present invention is a method of protecting a sulfonic acid functional group in an organic molecule as a substituted or unsubstituted neopentyl sulfonate ester. The method allows the conversion of R--SO.sub.3 --H to R'--SO.sub.3 --H, wherein R and R' are different organic radicals. Also disclosed is a method of increasing the bioavailability of drugs with a sulfonic acid functional group by protecting the sulfonic acid functional group as a substituted neopentyl sulfonate ester which has a masked heteroatom nucleophile. The masked nucleophile can be liberated in vivo, resulting in removal of the neopentyl protecting group and regeneration of the parent drug.

Abstract: A method of analysing a sample for alkyl ketene dimer (AKD) comprises treating the sample (or extract thereof) with a reagent which will react with an AKD to produce a detectable derivative. The preferred reagent is 4-(N,N'-dimethylamino)pyridine.

Abstract: The protective shield includes an elongated transparent shield member and a molded forearm support member having a forearm concavity spaced from the shield member by a dimension which provides additional protection to the person using the protective shield.

Abstract: A holder for SCUBA tanks or other similar cylindrical articles for storing such tanks along the deck of a boat or the like is molded from a unitary sheet having at least one concavity extending from the upper surface interiorly between the lateral sides, the sheet being sufficiently flexible that the weight of a SCUBA tank stored within the concavity causes flexure of the sheet so that the concavity rests on the supporting surface.

Abstract: Apparatus for testing and/or calibrating a detector comprising a latent image generator, the generator having differing reflectance coefficients across its surface such that in use, when irradiated by collimated radiation the output intensity from some regions is relatively high and from other regions is relatively low.

Abstract: A rural mailbox with a front inward swinging double door for mail delivery, a back door for mail retrieval, and a forward-and-backward sliding drawer for insertion and pickup of outgoing mail.

Abstract: A skylight structure offering superior water intrusion resistance has a glass plate superposed in spaced relationship above a plastic dome member having an integral inverted U-shaped flange. A cap marginally framing the glass and plastic members has spaced downwardly depending flanges with an inner shorter flange abutting the outer surfaces of the plastic flange and an outer longer flange spaced from and shielding the outer surfaces of the plastic flange. The outside lower end of the U-shaped flange is cured outwardly.

Abstract: A self-contained solar-powered illuminated reflector provides improved visibility at a distance as a traffic safety aid. A housing adapted to be secured to a highway or alternatively, to a vertical wall, encloses a reflector for reflecting light in a predetermined direction toward highway traffic, a light source, a battery and a photovoltaic system. The housing includes a window member for transmitting light outward from the light source in the predetermined direction toward highway or pedestrian traffic. An optical lightguide between the light source and the window member focuses the light from the light source so that the visible effectiveness of the light source is optimized. Circuitry is provided for selectively enabling the operation of the light source for minimizing the power requirement to extend the useful life performance of the traffic marker. The illuminated reflector is arranged to provide maintenance free and fail-safe operation over its useful life.

Abstract: A modulated optical radiation beacon, e.g. a flashing light beacon or an IR emmissive missile jamming source, can comprise a radiation source and two relatively movable apertured masks which, as the apertures thereof move into and out of registration, pass or block the radiation from the source. Herein, to improve the uniformity of the polar distribution of the emitted radiation (assuming, of course, that a uniform distribution is required) or, in other cases, simply to improve efficiency, the apertures of the `inner` mask, i.e. the one nearest the source, are bounded by curved reflective surfaces defining an optical cavity which at least crudely images the source at a position near the outer mask. Advantageously, the optical cavities are defined by a spaced array of prismatic members having appropriately curved facing surfaces.