Abstract: A spark sampling microparticle generator device and method providing means to first ionize a gap and then to switch a stabilized and controllable current into and out of said ionized gap to provide extremely high, selectable current density in a sample material in said gap with very fast rise and fall times to ablate said material to form microparticles. A plurality of identical modular circuits containing high frequency power transistors are selectably switchably connected in parallel simultaneously to the gap to achieve current densities which are higher than achievable with a single transistor, thereby obtaining the benefits of the high frequency response without being limited by the current limitations of the available transistors.

Abstract: A spectroanalytical system with radiation dispersing apparatus for dispersing radiation into a spectrum for concurrent application to an array of exit ports; sample excitation apparatus for exciting sample material to be analyzed to spectroemissive levels for generating a beam of radiation for dispersion by the dispersing structure; the exit port array including a corresponding array of detectors including a first detector positioned adjacent a first exit port positioned to sense first order radiation from an element of interest and a second detector positioned adjacent a second exit port to sense second order radiation from the same element of interest; and processing apparatus for responding to outputs of the first and second detectors to provide a compensated output as a function of the quantity of the element of interest in the sample material.

Abstract: A gas emission spectrometer and method for analyzing a continuously flowing gas stream using gas emission spectroscopy to measure low concentration levels of one or more gas/vapor impurities in the gas stream. Alternating power is applied to an electric discharge source to generate emissive radiation which is filtered into an optical signal at the emission wavelength of a preselected impurity gas. The optical signal is converted into an electrical signal which is selectively amplified within a narrow frequency range centered at substantially twice the excitation frequency of the alternating power source. The impurity concentration is measured from the amplified signal upon rectification.

Abstract: A non-conductive isolator for supporting a sample to be analyzed by radio frequency energy induced glow discharge techniques has a conductive ring for coupling a source of radio frequency energy to the same surface of a sample which is in direct contact with the induced glow discharge. An adapter kit for converting a direct current glow discharge analysis apparatus to a radio frequency energy induced flow discharge is also disclosed as well as the method of analyzing non-conductive and sample conductive using a source of RF energy coupled to the same sample surface being analyzed.

Abstract: A system and method for extending the limits of detection of plasma based sample analysis systems is disclosed. The preferred embodiment of the present invention system provides a reaction tube which is connected to both a furnace tube and a discharge tube. During use a nebulized sample is caused to pass through the furnace tube wherein its temperature is caused to become elevated. As well, a volatile atom containing, primarily molecular, gas is caused to flow through the discharge tube, while an energy providing electrical discharge occurs therein, such that dissociated volatile atoms are produced. The method of the present invention provides that typically elevated temperature nebulized sample, and the dissociated volatile atoms, be simultaneously entered into a reaction means wherein relatively easily dissociated molecules containing nebulized sample components are formed.

Abstract: The invention provides methods and apparatus for atomic emission spectroscopy and for mass spectrometry which make use of an inductively coupled radio-frequency plasma torch. A radio-frequency power supply supplies energy to a plasma induction coil via reflectometer means and a matching network. A signal indicative of reflected power generated by the reflectometer is used to set the frequency of the power supply to the resonant frequency of the matching network and plasma induction coil, thereby ensuring the maximum efficiency of power transfer irrespective of the state of the plasma. Preferably a solid state power amplifier is employed in conjunction with a lower power variable frequency oscillator. Means for ensuring proper ignition of the plasma while maintaining the frequency of the power generator within a governmentally specified frequency band are also provided.

Abstract: In the elemental analysis of an analyte present in a sample by optical or mass spectrometry, a nebulizer sprays the liquid sample into a chamber which has a wall transparent to infra-red radiation. Infra-red radiation from a heater external to the chamber is focused on to the droplets of sample as they emerge from the nebulizer, disrupting the droplets into smaller ones and evaporating solvent from them as they pass through the chamber. The thus desolvated sample stream is delivered into a plasma and the reaction accuracy within the plasma is qualified by the spectrometer.

Abstract: A method and means for accurately regulating the rate of flow of supply gas to the burner or torch of a spectrometer. The flow rate is controlled by a valve having a closure member which is movable between a position at which it provides maximum obstruction to gas flow, and a position at which it provides minimum such obstruction. The closure member movement is controlled by a pulsed electrical signal so that the closure member moves rapidly and repeatedly between each of the two positions. Gas flow rate through the valve is therefore dependent upon the aggregate of the times the closure member spends in either of the two positions referred to, and that flow rate is changed by varying the frequency and/or pulse duration of the pulsed signal.

Abstract: A sample is fed to an ICP-AES by applying suction to a mouth of the sample vessel extending into the central or inner capillary tube of the burner from an annular orifice or a plurality of spaced apart orifices. The amount of sample material is controlled by volume flow control or gas pressure control. The sample is in the form of a powder or vapor without dilution or entrainment of chemical contaminants.

Abstract: A sample processing system for use with analysis apparatus includes tubular structure that defines a continuous elongated flow chamber. The tubular structure has an inlet port at one end, an outlet port at the other end, and a sample inlet port in communication with the continuous elongated flow chamber between the inlet and outlet ports. A first pump flows diluent at a first rate through the inlet port for flow through the continuous elongated flow chamber, and a second pump flows a liquid mixture from the continuous elongated flow chamber through the outlet port at a rate greater than the first rate. With the sample inlet port submerged in a sample to be analyzed, the sample is aspirated through the sample inlet port into the flowing diluent stream in the continuous elongated flow chamber for dilution and application of the diluted sample mixture to sample analysis apparatus for analysis.

Abstract: The device as per the invention consists of a low pressure lamp incorporating an appropriately positioned microwave generator within the cavity. With this arrangement it is possible to obtain within the low pressure lamp microwaves of power very much greater than that which can be obtained using known systems involving the introduction of microwaves via coaxial cable, and such as to ensure greater excitation of the atoms forming the plasma produced in the lamp, consequently increasing the sensitivity of the analytical apparatus and markedly lowering the detectability limit of trace elements.

Abstract: A fluorescent lamp light output is maximized by cooling the cathode regions. Mercury vapor pressure is maintained at an optimum or desired level for light production by cooling the cathode areas of the lamp. The cooled cathode areas of the lamp collect cathode emissive material and mercury vapor condensates. Thus, the light output remains uniform and constant. The functional length of the lamp is not degraded by the deposition of either cathode material or mercury vapor condensates. Cooling can be effected by forcing cool air against the exterior of the lamp adjacent the cathodes or by using forced water heat exchangers. By cooling the respective cathode regions equally, the amount of deposition in the respective regions is substantially the same. Thus, gradations of deposition are avoided. The constant high output fluorescent lamp can be used with electronic inspection equipment and machine vision measurement devices.

Abstract: A follow-up system for monitoring the etching process in RIE equipment. A spectrometer is used in an interferometric mode for accurate thickness measuring to produce high-resolution and reproducible patterns in a layer of etchable material formed on a substrate.

Abstract: In a plasma generator for high-frequency supply of an induction coil containing a plasma of an aerosol with a substance to be analyzed, quarter-wave conductors of a quarter-wave resonant system are incorporated in the apparatus after having been divided and folded, which provides a significant saving in space. Added to the conductors are electric auxiliary circuitry for balancing the resonant system and for matching the frequency to a filled induction coil. The conduction coil is capable of up and down movement in a disturbance-free manner, the coil always being maintained at zero potential.

Abstract: A multiple frequency plasma torch activation circuit includes a system driver circuit with a pair of different frequency sources and a selector switch which allows one of the sources to be coupled to a splitter assembly which applies signals to a pair of independent power amplifiers having their outputs applied to a combiner assembly and to the plasma torch inductor. A detector circuit provides signals to a power control circuit which includes forward and reflected power monitoring and an impedance matching circuit for optimum coupling of the frequencies to the inductive load.

Abstract: The oxygen-selectivity of an atomic emission detection system is enhanced by introducing a carbon-containing, preferably non-oxygenated, gas as a portion of the reagent gas. In preferred embodiments, the reagent gas is nitrogen and/or hydrogen and up to about 50 volume percent of a C.sub.1 -C.sub.4 hydrocarbon gas.

Abstract: Separation of laser optogalvanic signals in plasma into two components: (1) an ionization rate change component, and (2) a photoacoustic mediated component. This separation of components may be performed even when the two components overlap in time, by measuring time-resolved laser optogalvanic signals in an rf discharge plasma as the rf frequency is varied near the electrical resonance peak of the plasma and associated driving/detecting circuits. A novel spectrometer may be constructed to make these measurements. Such a spectrometer would be useful in better understanding and controlling such processes as plasma etching and plasma deposition.

Abstract: This invention pertains to an atmospheric pressure capacitively coupled plasma formed inside a graphite furnace as a source for atomic emission spectroscopy. A capacitively coupled plasma device includes an electrically conducting, hollow elongated tube and an electrically conducting rod located coaxially and substantially inside the elongated tube, an ionizable gas present inside the cylindrical tube, and a mechanism of applying a high-frequency electric potential between the tube and the rod.

Abstract: A method of detecting an end point of etching by emission spectroscopy. Using a constant ratio between emission intensities in the course of etching and after the termination thereof, a correction value is computed with data of a waveform already adjusted to be capable of detecting an end point of etching and the corresponding emission intensity in the course of etching treatment thereafter, and the waveform of corresponding emission intensity in the course of etching treatment is processed so that the detection can be conducted on the same level as in the end point detection already adjusted to be capable of detecting the end point of etching at the time of treatment. Thus, irrespective of the reduction of the quantity of emission for an emission detection at each time of treatment, a constant electric signal of the same detecting level can be obtained, making it possible to detect an end point of etching with the same accuracy as in the initial treatment.

Abstract: A method of in situ monitoring of a body of a fluid stored in a tank or groundwater or vadose zone gases in a well for the presence of selected chemical species uses a probe insertable into the well or tank via a cable and having electrical apparatus for exciting selected chemical species in the body of fluid. The probe can have a pair of electrodes for initiating a spark or a plasma cell for maintaining a plasma to excite the selected chemical species. The probe also has optical apparatus for receiving optical emissions emitted by the excited species and optically transmitting the emissions via the cable to an analysis location outside the well. The analysis includes detecting a selected wavelength in the emissions indicative of the presence of the selected chemical species.

Abstract: A novel atmospheric pressure capacitively coupled ratio frequency plasma discharge method and apparatus. The apparatus is suitable for atomic absorption and atomic emission analysis of discrete sample volumes (1-50 .mu.l). The plasma can be operated at very low Radio Frequency (RF) input powers (10-600 W) which allow for optimal conditions for atom resonance line absorption measurements. Sample vaporization for analysis in the plasma is done by an electrically heated tantalum strip vaporizer. The vaporization and dissociation-atomization steps are separately controlled. Analyte absorption takes place in the plasma discharge which is characterized by a long path length (10-50 cm) and low support gas flow rate (0.05 to 6 L/m) both of which provide for a relatively long residence time. The device exhibits linear calibration plots and provides sensitivities in the range of from 3.5-40 pg.

Abstract: A atmospheric pressure capacitively coupled plasma high intensity spectral lamp. The lamp generates atom line and ion line spectra from a substance to be analyzed. The lamp comprises a hollow means adapted for containing and sustaining an atmospheric pressure capacitively generated plasma discharge, a first electrode connected to a radio frequency power supply, electrically insulated from the plasma and enclosing at least a portion of the hollow means, and a second electrode constructed of the substance to be analyzed, connected to a radio frequency power supply, the electrode penetrating into the plasma discharge and being capacitively arranged with the first electrode.

Abstract: An inductively coupled plasma spectroscopy apparatus is provided in which an inductively coupled plasma torch and an analyte sample atomizer are integrally formed as a single unit. The atomizer portion of the apparatus includes two electrodes and a plasma nozzle through which a heating element is placed. Test samples may be placed into a sample vessel which is positioned within the heating element. The torch portion includes a glass containment wall surrounding at least a portion of the plasma nozzle to define a plasma chamber located immediately adjacent to the sample vessel. The glass containment wall contains a radio frequency (RF) coil wrapped about its periphery which is inductively coupled to a supply of gas. A variable rate cooling manifold is also provided about the periphery of the containment wall. The integral design effectively reduces the buildup of memory condensate within the apparatus, thereby decreasing contamination and improving the sensitivity of the results obtained.

Abstract: This invention pertains to a novel plasma detector that is useful for the detection of compounds separated by gas chromatography. More particularly, the invention relates to a novel radio-frequency, atmospheric pressure capacitively coupled plasma torch which can be used as an element specific, spectroscopic detector for gas chromatography. A method of detecting compounds separated by gas chromatography comprising passing the gas product of a gas chromatograph through a radio-frequency atmospheric pressure capacitively coupled plasma and anaylzing the results.

Abstract: A method and apparatus for controlling measurement repeatability in spectrochemical analysis which analysis utilizes a plasma source is shown to include a plasma generator for providing energy to the plasma source to sustain plasma, a sensor for sensing the operating temperature of the plasma generator and a temperature controller for controlling the operating temperature of the plasma generator in response to the temperature sensed by the sensor. The temperature controller controls the operating temperature of the plasma generator either within a temperature range, such as between 100.degree. C. or at a set point temperature. In the case of a magnetron having heat conductive fins as the plasma generator, the sensor senses the temperature of at least one of said fins and the temperature controller includes a fan directed to move air across the fins and a speed controller for controlling the speed of the fan in response to the sensed temperature of the fins.

Abstract: In a device for supplying liquid to an atomization device operating with a nebulizer (22) in a spectrometer, the liquid is fed to the nebulizer (22) by a peristaltic pump (10) through a supply conduit (12). A valve (18) responding to liquid pressure is arranged closely in front of the nebulizer (22) and controls a connection between the supply conduit (12) and an outlet (30) through which excess liquid can flow off. A sensor (44) responding to the opening of the valve (18) is adapted to control the speed of the peristaltic pump (10), such that the quantity fed by the peristaltic pump (10) is slightly larger than the feeding capacity of the nebulizer (22).

Abstract: A spectroscope apparatus includes a device for separating light from an object to be measured into spectral components, a device for mixing spectral components which exists in a desired wavelength range, and a device for forming an image of the to-be-measured body of mixed light. The image obtained is very useful for observing the state of a combustion flame, the progress a photochemical reaction, the progress of a biochemical reaction, tissue in a cell, and the state of a flame for analyzing a solution which contains a metal ion by flame spectrophotometry. The apparatus provides accurate analytical information and makes possible precise control operations.

Abstract: A method of determining the amount of nutriment absorbed in living organisms comprising animals, fish and plants comprises adding to the animal, fish or plant food one or more elements from the lanthanide series as tracers. After the nutriment has been absorbed, a sample is taken from a localized part of the living organism, for example a fish scale, and the sample is analyzed by ICP (inductively coupled plasma) to determine the amount of tracer and thus the amount of absorbed nutriment in the living organism.

Abstract: A closed inductively coupled plasma cell generates a relatively high power, low noise plasma for use in spectroscopic studies. A variety of gases can be selected to form the plasma to minimize spectroscopic interference and to provide a electron density and temperature range for the sample to be analyzed. Grounded conductors are placed at the tube ends and axially displaced from the inductive coil, whereby the resulting electromagnetic field acts to elongate the plasma in the tube. Sample materials can be injected in the plasma to be excited for spectroscopy.

Abstract: A demand modulated electrothermal atomization plasma spectroscopy system intended to reliably and controllably atomize samples. The invention is used in conjunction with a plasma spectroscopic instrument, and includes a feedback control loop that monitors the rate of analyte consumption in a plasma torch and regulates the temperature of an electrothermal atomization means that supplies analyte material to the plasma torch. The feedback system in the preferred embodiment regulates atomization temperature based upon ion or photon count rates.

Abstract: A plasma trace element spectrometer comprises a microwave generator for generating microwave power, a microwave feeder for guiding and transforming the generated microwave power into microwave power of TE.sub.01 mode and supplying the microwave power of TE.sub.01 mode, a plasma producer having, at one end, an introduction port for a carrier gas and a sample and at the other end an opening and being cooperative with the supplied microwave power of TE.sub.01 mode to produce plasma of the carrier gas and sample introduced through the introduction port, and a spectrometer for analyzing constituent elements of the sample by measuring the produced plasma by way of the opening.

Abstract: For nebulizing sample liquid for spectroscopical purposes a liquid to be nebulized is pressurized to a minimum pressure of 30 bar through a high-pressure pump formed as a separate unit, and is nebulized through a nozzle having a smallest flow aperture of less than 5.multidot.10.sup.-9 m.sup.2. The high-pressure pump and the nozzle are interconnected through conduits. In one embodiment the pump takes in pure solvent. The sample is taken in on the high-pressure side through a loop, which is arranged to be connected between pump and nozzle.

Abstract: A method and apparatus for element specific detection in chromatogragphic eluents. The apparatus is comprised of a radio frequency discharge between electrodes in helium, and utilizes a low-resolution plasma emission spectrometer to monitor selected spectral emissions produced when the helium discharge decomposes and excites the atomic constituents in chromatographic column effluents. The spectrometer is tuned to an atomic emission line in the near-infrared portion of the spectrum, and the emission intensity from the discharge region of a selected line is used to monitor the concentration of the element producing that line. Acceptable detector sensitivity is achieved by the use of a high-throughput optical system. Selectivity is achieved by a combination of correct line selection, plasma and carrier gas purification, and plasma gas doping.

Abstract: Apparatus for analysing elements by inductive plasma spectrometry produced by the air. It comprises a tube, means for producing within said tube a plasma containing the element and means for the spectrometric analysis of the like from the plasma. The plasma production means incorporate means for circulating air in the tube, said air serving to produce the plasma. Application to the analysis of an element contained in the air.

Abstract: Methods and apparatus are provided for qualitative and quantitative determination of constituents of a sample of material. The method prepares the sample for analysis by mixing the sample with a preselected quantity of a preselected material that serves to transport and project the sample. The mixture may be pyrolyzed and/or injected into a plasma. A spectrometric detection is made of the sample in the plasma. The apparatus is a modified electrothermal vaporization furnace whose sample outlet is connected to the sample inlet of an inductively-coupled plasma-mass spectrometer (ICP-MS). An additional gas (oxygen) injection line is provided between the sample outlet of the furnace and the sample inlet of the ICP-MS.

Abstract: A spectroscope apparatus includes means for separating light from an object to be measured into spectral components, means for mixing that part of the spectral components which exists in a desired wavelength range, and means for forming an image of the to-be-measured body of mixed light. The image thus obtained is very useful for observing the state of a combustion flame, the progress of photochemical reaction, the progress of biochemical reaction, a desired tissue in a cell, and the state of a flame for analyzing a solution which contains a metal ion, by flame spectrophotometery, that is, provides accurate information and makes possible a precise control operation.

Abstract: An analysis system includes a sample inlet, a diluent inlet, and a mixing chamber that has an outlet through which a mixture of the sample and diluent is flowed and in which a mechanical mixing member is housed. Positive displacement pumps preferably concurrently flow diluent to the mixing chamber and draw diluted sample to be analyzed from the mixing chamber. Bubble separation apparatus has a first branch connected to a drain and a second branch connected to the analyzer input. In a particular embodiment, the analyzer apparatus includes a nebulizer that controls the flow rate of the bubble-free stream through the second branch, sample excitation apparatus in the form of an induction coupled plasma (ICP) torch for exciting the sample to spectroemissive levels, and means for spectroanalysis of the excited sample at the output of the torch.

Abstract: There is disclosed a visible emission spectrum generating assembly for a gaseous mixture comprising a chamber for receiving the gases to be analyzed, electrodes positioned externally about the chamber and longitudinally disposed with respect to one another, an rf energy source connected to the electrodes to establish a current therebetween for generating the visible emission spectra of the gaseous mixture to be analyzed and at least one photodetector device disposed proximate the chamber to receive the thus generated light or visible emission spectra. The process and apparatus of the present invention also include a data processing device for evaluating the spectral signals received by the photodetector device and suitable display and/or recording assemblies.

Abstract: Radioactive materials can be safely analyzed by an emission spectroscopic analyzer comprising an exciting device for exciting a radioactive material to be analyzed to emit light. The exciting device is enclosed in a radiation shielding wall. A detecting device detects the emitted light. The detecting device is located outside the radiation shielding wall. A light-transmitting device is provided between the exciting device and the detecting device such that the emitted light impinging on a first end of the light-transmitting device will be received at the detecting device as light having been transmitted through the light-transmitting device and emitted from a second end of the light-transmitting device. The light-transmitting device penetrates a hole made in the radiation shielding wall which has a sealing structure to prevent radiation leakage. The light-transmitting device penetrates the hole with a curvature.

Abstract: The nitrogen-selectivity of an atomic emission detection system is enhanced by use, as the reagent gas, of a single gas or a mixture of gas components containing oxygen and hydrogen in an oxygen/hydrogen molar ratio of about 1:10 to 10:1.

Abstract: An induction plasma system comprises a torch and an induction coil. A sample substance is injected into the plasma at an axial position that is adjustable while the plasma is being energized. The plasma-forming gas flows through the induction coil prior to passing through the plasma torch. A piezoelectric crystal is used for initiating the plasma. An oscillator network generates radio frequency power at a first frequency, and an output LC network that includes the induction coil is tuned to a second frequency higher than the first frequency. Means for maintaining constant power to the plasma includes an AC circuit for duty cycling AC power input to a DC power supply in response to a feedback signal relative to the rectified voltage. Thus a change in the rectified voltage effects an inverse change in the duty cycling such as to nullify the change in the rectified voltage.

Abstract: A temperature detecting device detects infrared rays from an object to be measured and determines the temperature of the object based on the detection result. To avoid the influence of contamination adhered to the infrared ray incident surface of an infrared ray detecting unit, a correction coefficient for the detection result of the infrared ray detecting unit is determined before actual temperature detecting starts. For this purpose, the infrared rays fed from the object into the infrared ray detecting unit are interrupted by a shutter device. The infrared ray detecting unit detects the infrared rays fed from the shutter device through the infrared ray incident surface, and it outputs a first detection value corresponding to the shutter temperature. A shutter temperature detecting element directly detects the actual temperature of the shutter device, and it outputs a second detection value corresponding to the actual temperature of the shutter device.

Abstract: An improved emission spectrochemical analyzer is disclosed in which light from a sample in high-temperature plasma is led to an absorption cell, a magnetic field is applied to the absorption cell to utilize the Zeeman effect, the absorption cell is further pressurized to make the width of the absorption line of a desired element equal to the width of the resonance emission line of the element, and only the resonance emission line of the element is selected by appropriate modulation means and detected at high sensitivity.

Abstract: A constant current source for maintaining an essentially constant current flow through an r. f. glow discharge reaction occurring in a reactor uses a balancing capacitor, a center tap current transformer, a bridge circuit having two identical circuit legs, a differential amplifier, an error signal generating circuit, an operational amplifier, and voltage and current generator circuitry consisting of an oscillator, two transformers, MOS driver transistors and a filter circuit. Currents in the primary winding of the transformer caused by parasitic capacitance of the reactor and by the balancing capacitor effectively cancel each other out. This results in a voltage signal generated by the bridge circuit, which is coupled to the secondary winding of the transformer, that is proportional only to current flowing through the r. f. glow discharge reaction. This voltage signal is compared by the error signal generating circuit with a reference voltage which is proportional to a desired current level through the r. f.

Abstract: The invention relates to an arrangement and method for multielement analyse of chemical elements in which light cables are used to transmit spectral lines or bands produced by an optical dispersion means from a sample material radiation to an array of photodetectors. The light cable end-portions are inserted as many as required for a definite analyzing program into holes of a plug-in unit and are associated via a mask to definite photodetectors. The plug-in unit is displaceable relative to the mask so that the spectral informations from definite light cables associated to definite spectral lines or bands are evaluated in groups which require similar or equal excitation conditions. The latter are adjustable by respective means.

Abstract: A method of analyzing a volatile, air or moisture sensitive or pyrophoric, liquid, organometallic compound for an impurity comprising inserting a sample of the compound into an exponential dilution flask, allowing substantially the entire sample to vaporize, and analyzing the vapor by plasma spectroscopy; or decomposing the sample by dropwise addition into frozen aqueous acid, diluting the decomposed sample with water, and analyzing the diluted, decomposed sample by plasma spectroscopy.

Abstract: The invention relates to an air-tight, shielded enclosure equipped for emission spectrometry. The air-tight enclosure (4) outside of which the high-frequency generator (1) and the spectrometer (3) are located, contains the inductor plasma source (2). The enclosure is provided with an insulating and biologically protective high-frequency lead-through (6), a Faraday cage (16), an air removing hood (17), and a baffle output (24) of the image of the plasma. This equipment makes it possible to apply emission spectrometry to the analysis of radioactive elements.

Abstract: The radio frequency powered gas discharge tube of an atomic emission detector is cooled with a flow of liquid, and means are provided for grounding points in the flow that are on opposite sides of the radio frequency field so as to reduce the amount of radio frequency energy escaping from the discharge tube in the liquid.

Abstract: An optical arrangement for use in spectrometry uses a masking device which eliminates unwanted spectral regions prior to optically resolving the unmasked information. The optical arrangement comprises an entrance slit to select incidence spectral energy from an energized source and a concave grating of relatively low dispersion to image the spectrum of the entrance slit onto a stationary mask which simultaneously selects spectral regions of the dispersed incident spectral energy. The selected spectral regions are collimated and recombined and directed onto an Echelle grating to disperse with high resolution the selected spectral regions. A concave mirror focuses the dispersed selected spectral regions into a focal plane of highly resolved spectral energy which can be detected to determine the spectral information coming from the source. The optical arrangement is particularly well suited for use with narrow spectral bandwidth spectral information distributed over a large spectral range.

Abstract: A method for generating an aerosol powder from a melt includes an atomization die having an orifice through which the melt passes to create the powder. In a preferred embodiment, the orifice has a dimension less than 5 millimeters, and may include a heater to prevent freeze-off. The die may be included in a high-temperature probe suitable for immersion on the melt, so that accumulated accretions of powder on the walls of the probe may be melted off by heating the probe.