Abstract: A crucible handling shuttle includes a pair of opposed dual crucible-gripping arms mounted on a rotatable head and moves between an induction furnace pedestal and a crucible loading station, such that one pair of arms pick up a crucible loaded with a preweighed sample, the shuttle moves to the induction furnace, where the other pair of arms grip and remove a spent crucible. The shutter head then rotates to deposit the new sample-holding crucible onto the pedestal and subsequently moves out of the furnace area to a sample disposal chute positioned between the crucible loading station and the furnace, whereupon the spent crucible is dropped for disposal. The shuttle head is then rotated and moved to the loading station to pick up a new crucible.

Abstract: An analytical induction furnace and method for combusting conductive sample materials (500) utilizing a crucible for holding a sample within the induction furnace. Less than one gram of accelerator material is then inserted into the crucible with the sample and the induction furnace is activated for a predetermined time period (503) for thoroughly combusting the sample and accelerator. In some instances, no accelerator is required with the sample at frequencies of approximately 4.5 MHz. The invention provides for the induction furnace that is actuated in an RF frequency range between 2-9 MHz with little to no accelerator for thoroughly melting the sample for use in an analytical instrument.

Abstract: A crucible handling shuttle includes a pair of opposed dual crucible-gripping arms mounted on a rotatable head and moves between an induction furnace pedestal and a crucible loading station, such that one pair of arms pick up a crucible loaded with a preweighed sample, the shuttle moves to the induction furnace, where the other pair of arms grip and remove a spent crucible. The shutter head then rotates to deposit the new sample-holding crucible onto the pedestal and subsequently moves out of the furnace area to a sample disposal chute positioned between the crucible loading station and the furnace, whereupon the spent crucible is dropped for disposal. The shuttle head is then rotated and moved to the loading station to pick up a new crucible.

Abstract: A transformer assembly (300) for use with an internal load (307) includes a transformer core (323) having a primary winding (405). A first electrode (303) and second electrode (319) are used for contacting an internal load (307). A secondary circuit is formed that includes the first electrode (303), the second electrode (319) and conductors (301,313, 317) positioned between the first electrode (303) and second electrode (319). The transformer assembly (300) is arranged so that the conductors (301, 313, 317) surround the primary winding (405), transformer core (323), the first electrode (301) and second electrode (319). The transformer assembly (300) may be used in an electrode furnace or other high current and voltage applications requiring high efficiency in a small package.

Abstract: A pulse-width-modulated voltage is applied to an IR emitter during the on-time of a primary drive voltage having a frequency of about 2.5 Hz in order to control the power to a predetermined desired level. The secondary modulation is at about 800 Hz. The lower response time of the emitter will, in effect, filter the higher frequency, and it will appear that an average power is being applied to the emitter during the on-time.

Abstract: An improved sample handling carousel is mounted to an analytical furnace at an acute angle and includes sample holding cavities which are readily visible at eye level to an operator. The rotary carousel can be easily removed from a stepwise driven drive shaft for filling the carousel at a remote location, such as a weighing station, or can be filled directly while mounted on the drive shaft. A tray is positioned below the carousel and has a slot for dropping a sample when one of the sample holding cavities aligns with the slot in the tray. In a preferred embodiment of the invention, the carousel is made of aluminum or a transparent polymeric material, such as acrylic.

Abstract: An electrode for a resistance analytical furnace has a crucible-engaging surface and an end spaced from the crucible-engaging surface having a plurality of grooves formed therein. A manifold mounted on the end of the electrode defines a dust recovery plenum and includes an outlet communicating with the plenum for coupling to a vacuum source to remove debris from the electrode. The improved electrode and electrode cleaning manifold positioned on the electrode provides a turbulent airflow for removal of dust and debris from an analytical furnace.

Abstract: A final scrubber in the inert carrier gas flow path of an elemental analyzer includes a manifold with valves for selectively bypassing a quick disconnect final scrubber housing that includes a filter tube and sealed gas fittings. The housing includes alignment members and a latch for positioning and locking the housing onto and in sealed engagement with the instrument's manifold. A switch detects the presence of the housing, and a control circuit controls valves to direct the inert gas flow though the filter tube or bypass the filter tube when the housing is removed. With this system, the final scrubber can be removed and replaced quickly without the use of tools while the carrier gas continues to flow though the furnace without interruption. Also, the valves can be closed to allow for segmented leak detection of the instruments gas flow path.

Abstract: The IT and FT values for coal and coke samples can be accurately predicted by applying equations to determined ST and HT temperatures. For reducing atmospheres, the equations are IT=C1×ST?C2×HT+C3 and FT=C4×HT?C5×ST+C6. For oxidizing atmospheres, the equations are IT=C7×ST?C8×HT+C9 and FT=C10×HT?C11×ST+C12. IT is the initial deformation temperature. ST is the softening temperature. HT is the hemispherical temperature. FT is the fluid temperature. C1-C12 are constants determined by multi-linear regression coefficient analytical techniques on a collection of data.

Abstract: An automatic cleaning assembly for an analytical furnace is detachable from the filter chamber above the combustion tube. The cleaning assembly includes a rotating brush which is lowered through the filter chamber and into the combustion tube while a vacuum is drawn through the lower seal of the combustion tube. This results in a higher vacuum pressure differential and improved flow rate for removing dust from the filter of the furnace and the combustion tube.

Abstract: An analytical combustion furnace has an input port for receiving a holder for an analytical sample. A purge block is coupled to the input port of the combustion furnace and has an input end for receiving the holder and a gas inlet and a gas outlet. A door selectively closes the input end of the purge block, and a pressurized seal is coupled between the purge block and the door. A source of purging gas is coupled to the gas inlet of the purge block for pressurizing the seal. The gas outlet of the purge block communicates with the seal to allow purging gas to escape the area of the seal. In one embodiment, a pressurized seal surrounds a push rod, which seal is pressurized by a purging gas to continuously purge the entry of the push rod into the purge block, thereby eliminating atmospheric contamination.

Abstract: A data acquisition system and method are described that may be used with various spectrometers. The data acquisition system may include an ion detector, an initial processing module, and a spectra processing module. The initial processing module is provided for processing the ion detection signals and for supplying processed signals to the spectra processing module. The spectra processing module generates spectra from the processed signals and supplies the generated spectra to an external processor for post-processing. The spectra processing module may include one or more of: a cross-spectra filter for filtering data in each spectra as a function of data in at least one prior spectra; a shaping filter for removing skew and shoulders from the processed signals; a sharpening filter for sharpening the peaks of the processed signals to effectively deconvolve and separate overlapping peaks; an ion statistics filter; and a peak histogram filtering circuit.

Abstract: A data acquisition system and method are described that may be used with various spectrometers. The data acquisition system may include an ion detector and a processing circuit. The processing circuit may include an initial processing module and a spectra processing module. According to one embodiment, the spectra processing module generates stick spectra and supplies the stick spectra to an external processor. The stick spectra comprise a peak intensity, resolution, and a location in the spectra for each detected peak. The stick spectra may be generated in real time.

Abstract: Ion manipulation systems include ion repulsion by an RF field penetrating through a mesh. Another comprises trapping ions in a symmetric RF field around a mesh. The system uses macroscopic parts, or readily available fine meshes, or miniaturized devices made by MEMS, or flexible PCB methods. One application is ion transfer from gaseous ion sources with focusing at intermediate and elevated gas pressures. Another application is the formation of pulsed ion packets for TOF MS within trap array. Such trapping is preferably accompanied by pulsed switching of RF field and by gas pulses, preferably formed by pulsed vapor desorption. Ion guidance, ion flow manipulation, trapping, preparation of pulsed ion packets, confining ions during fragmentation or exposure to ion to particle reactions and for mass separation are disclosed. Ion chromatography employs an ion passage within a gas flow and through a set of multiple traps with a mass dependent well depth.

Abstract: A crucible handling shuttle includes a pair of opposed dual crucible-gripping arms mounted on a rotatable head. The shuttle is removably plugged into a sliding block of a carriage to move between a furnace and a crucible loading station. The carriage includes mechanical, electrical, and pneumatic plugs or sockets which couple to mating sockets or plugs of the shuttle. A linear actuator extends between the carriage and the furnace base to raise and lower the carriage and shuttle coupled thereto.

Abstract: A combustion tube mounting system releasably mounts a combustion tube to an aperture in the floor of a furnace housing. The combustion tube has a base assembly with a cam and can be manually or automatically unlocked by cam pins in the floor for selectively engaging the cam for lowering the combustion tube from the floor of the furnace. When a new combustion tube is placed on the lower seal assembly and raised, it automatically aligns and engages the upper furnace seal and engages cams on the floor of the furnace housing which lock the combustion tube in place as it is introduced into the furnace.

Abstract: The IT and FT values for coal and coke samples can be accurately predicted by applying equations to determined ST and HT temperatures. For reducing atmospheres, the equations are IT=C1×ST?C2×HT+C3 and FT=C4×HT?C5×ST+C6. For oxidizing atmospheres, the equations are IT=C7×ST?C8×HT+C9 and FT=C10×HT?C11×ST+C12. IT is the initial deformation temperature. ST is the softening temperature. HT is the hemispherical temperature. FT is the fluid temperature. C1-C12 are constants determined by multi-linear regression coefficient analytical techniques on a collection of data.

Abstract: Circuits for correcting base line shift of the detector coupling circuit of a TOFMS provide gain and impedance characteristics that compensate for the AC coupling effect of the detector. In one circuit, base line correction is achieved by injecting a current equal to that which flows due to the buildup charge in the detectors AC coupling network. In another circuit, the current source drives an integrator which is coupled to the signal path to reduce the detector AC coupling effects. In another circuit, a low noise amplifier utilizes a feedback network that reduces the detector AC coupling effects. In yet another circuit, an operational amplifier is employed to reduce the detector AC coupling effects.

Abstract: The IT and FT values for coal and coke samples can be accurately predicted by applying equations to determine ST and HT temperatures. For reducing atmospheres, the equations are IT=C1×ST?C2×HT+C3 and FT=C4×HT?C5×ST+C6. For oxidizing atmospheres, the equations are IT=C7×ST?C8×HT+C9 and FT=C10×HT?C11×ST+C12. IT is the initial deformation temperature. ST is the softening temperature. HT is the hemispherical temperature. FT is the fluid temperature. C1-C12 are constants determined by multi-linear regression coefficient analytical techniques on a collection of data.

Abstract: A data acquisition system and method are described that may be used with various spectrometers. The data acquisition system may include an ion detector, an initial/transient processing module, and a spectra processing module. The initial/transient processing module is provided for processing the ion detection signals and for supplying processed signals to the spectra processing module. The transient processing module may contiguously sample the ion detection signals at a rate of at least 1.5 GHz. The spectra processing module may generate spectra from the transients at a rate of at least 50 spectra per second. The initial processing module may be configured to have a sensitivity that is sufficient to detect a single ion received within one of over at least 100 transients and to detect and quantify a number of ions simultaneously striking said ion detector up to at least 10 simultaneously striking ions.