Abstract: A simplified method for solid phase extraction of components of interest from a sample employing a syringe in which the inner surface of the cannula or needle is at least partially coated with a stationary phase such that aspirating the sample into the needle results in adsorption of the components of interest into the stationary phase. Aspiration of a solvent may be employed for removing the components of interest from the stationary phase for direct injection into a chromatographic instrument, or the components of interest may be removed by thermal desorption, wherein the needle is placed in the injection port of the chromatographic instrument and heated.

Abstract: A cap for sealing pressure vessels is disclosed. The present invention permits a nominal closure to be formed by hand tightening and a substantially higher force to be applied to a cap by a separate clamp mechanism, thereby forming a pressure seal. In certain preferred embodiments, means for providing a process flow through a hole in the seal and filtering means are also provided as part of the cap assembly. A preferred application of the cap of the present invention is for the sealing of sample vessels used for supercritical fluid extraction of compounds from a solid matrix for subsequent chemical analysis. Methods of supercritical fluid extraction are also disclosed. The present invention thus provides methods and apparatus whereby the placement of a sample into a pressurized system may be automated and monitored to ensure adequate seals have been created and maintained within such pressurized systems.

Abstract: A cap for sealing pressure vessels is disclosed. The present invention permits a nominal closure to be formed by hand tightening and a substantially higher force to be applied to a cap by a separate clamp mechanism, thereby forming a pressure seal. In certain preferred embodiments, means for providing a process flow through a hole in the seal and filtering means are also provided as part of the cap assembly. A preferred application of the cap of the present invention is for the sealing of sample vessels used for supercritical fluid extraction of compounds from a solid matrix for subsequent chemical analysis. Methods of supercritical fluid extraction are also disclosed. The present invention thus provides methods and apparatus whereby the placement of a sample into a pressurized system may be automated and monitored to ensure adequate seals have been created and maintained within such pressurized systems.

Abstract: A conveyor apparatus for receiving and transporting cylindrical stock or articles past work stations includes a plurality of rollers disposed along spaced-apart parallel axes. The rollers are driven through one-way or overrunning clutches and rotate cylindrical stock disposed between adjacent pairs of rollers. At a work station, a moving member such as a belt engages the stock and rotates it at a speed higher than the speed imparted to it by the rollers. The overrunning clutches release the conveyor rollers and rotate with the stock at a correspondingly higher speed. The constant, non-slipping contact between the rollers and stock minimizes such difficulties as scoring of the stock and significantly improves product quality and appearance.

Abstract: A conveyor apparatus for receiving and transporting cylindrical stock or articles past work stations includes a plurality of rollers disposed along spaced-apart parallel axes. The rollers are driven through one-way or overrunning clutches and rotate cylindrical stock disposed between adjacent pairs of rollers. At a work station, a moving member such as a belt engages the stock and rotates it at a speed higher than the speed imparted to it by the rollers. The overrunning clutches release the conveyor rollers and rotate with the stock at a correspondingly higher speed. The constant, non-slipping contact between the rollers and stock minimizes such difficulties as scoring of the stock and significantly improves product quality and appearance.