Abstract: Secure documents and methods and apparatus for making the same. The documents are made secure using apparatus and methods in which one or more taggants are placed in the paper or ink of the document. The present or absence of the taggant within the document is detected by x-ray fluorescence analysis, thereby identifying or verifying the document.

Abstract: Secure documents and methods and apparatus for making the same. The documents are made secure using apparatus and methods in which one or more taggants are placed in the paper or ink of the document. The present or absence of the taggant within the document is detected by x-ray fluorescence analysis, thereby identifying or verifying the document.

Abstract: A convenient apparatus and method for inserting surrogate metal-entraining aerosols into exhaust stacks for the purpose of realistic dynamic testing of an emissions monitor. The aerosols contain elements required to be detected by the monitor. The 14 metals regulated by the EPA as hazardous air pollutants are of particular interest. The method requires less time and fewer skilled technicians than conventional testing methods. In a preferred embodiment of the present invention, a burner (e.g., propane or kerosene) is combined with a combustion chamber, a fan, an air compressor, at least one peristaltic pump, at least one surrogate reservoir, and the necessary ductwork for connection to an exhaust stack. The amount of surrogate aerosol to be introduced to the stack is adjusted at the peristaltic pump. After heating by the burner and subsequent introduction into the hot stack, the surrogate homogeneously mixes with the exhaust stream and is presented to the sensor as a dry gas component of the exhaust stream.

Abstract: An intra-microspray ICP torch for use in conjunction with spectographic analysis generates a high temperature ionized gas in a plasma region at one end of the torch, and includes a preshaped tube mounted within the torch, with a first end of the tube terminating adjacent the plasma region, and a nebulizer mounted to a second end of the tube. The preshaped tube has at least one set of impactors that define at least two chambers, the impactors blocking the line of sight between adjacent chambers. The nebulizer propels a pressurized aerosol/sample mixture at the impactors, toward the plasma region. The impactors divert the mixture as it travels from chamber to chamber toward the plasma region, causing a filtering effect that promotes passage to the plasma region of sample particles having a size of about 15 microns or less, thereby resulting in optimum spectrographic clarity.

Abstract: An improved pre-aligned demountable plasma torch wherein the three tubes that are generally used in demountable plasma torches are now joined together with standard taper joints. The axis of the standard taper joints are essentially centrally aligned with the central long axis of the tubes so that the tubes are pre-aligned and essentially concentric in the assembled torch. If any of the tubes becomes damaged in use they can be replaced with a similarly constructed tube with a minimum of interruption and expense, without the need to adjust the tubes to be essentially concentric and in an assembly consisting of only 3 parts.

Abstract: A DCP spectrometer emission source for creating a conical high temperature plasma through which an aerosol suspended sample is able to penetrate which generally includes at least three D.C. powered electrodes, a base structure for circumferentially spacing the electrodes about a central axis, and an introduction conduit associated with the central axis for injecting the aerosol sample stream into the conical shaped plasma created by the electrodes. The base structure circumferentially spaces the electrodes about the central axis such that the longitudinal axes of the electrodes converge radially toward the central axis at an acute angle to the central axis. Each of the electrodes has an electrode member and a conduit for conveying an ionizable gas passed the electrode members. The electrode members are also connected to a source of D.C. electrical power such that two of the electrode members have the same polarity and the third electrode member has the opposite polarity.

Abstract: Disclosed is a novel apparatus for the production of a sustained inductively coupled non-argon plasma discharge in flowing gas in a 13-25 mm (analytical size) containment tube at atmospheric pressure. The apparatus is developed for elemental analysis of injected aerosol or powdered samples, and particularly for air monitoring applications.