Abstract: Chemical composition of liquid phase samples is determined based on laser induced ablation spectroscopy of droplets. An aerosol jet comprising a carrier gas and liquid phase sample droplets, less than about 10 microns in diameter, is formed. An emissive plasma plume is generated from the sample droplets using a pulsed laser to deposit energy at a focal point in the aerosol jet. Light from the plasma plume is gathered with a concave mirror and focused into one end of a fiber optic lightguide. The lightguide can transmit spectral emissions from the plume to a spectrometer/detector which can send wavelength and intensity values to a computer. The computer is operable to determine a liquid sample composition based on the wavelength and intensity values.

Abstract: Apparatus for laser induced ablation spectroscopy (LIBS) is disclosed. An apparatus can have a computer, a pulsed laser and a lightguide fiber bundle that is subdivided into branches. One branch can convey a first portion of the light to a first optical spectrometer and a different branch can convey a second portion of the light to another optical spectrometer. The first spectrometer can be relatively wideband to analyze a relative wide spectral segment and the other spectrometer can be high dispersion to measure minor concentrations. The apparatus can further comprise an unbranched lightguide fiber bundle to provide more light to a low sensitivity spectrometer. The apparatus can include an inductively coupled plasma mass spectrometer ICP-MS and a computer instructions operable to provide normalized LIBS/ICP-MS composition analyses.

Abstract: Apparatus for laser induced ablation spectroscopy (LIBS) is disclosed. An apparatus can have a computer, a pulsed laser and a lightguide fiber bundle that is subdivided into branches. One branch can convey a first portion of the light to a first optical spectrometer and a different branch can convey a second portion of the light to another optical spectrometer. The first spectrometer can be relatively wideband to analyze a relative wide spectral segment and the other spectrometer can be high dispersion to measure minor concentrations. The apparatus can further comprise an unbranched lightguide fiber bundle to provide more light to a low sensitivity spectrometer. The apparatus can include an inductively coupled plasma mass spectrometer ICP-MS and a computer instructions operable to provide normalized LIBS/ICP-MS composition analyses.

Abstract: Apparatus for laser induced ablation spectroscopy (LIBS) is disclosed. An apparatus can have a computer, a pulsed laser and a lightguide fiber bundle that is subdivided into branches. One branch can convey a first portion of the light to a first optical spectrometer and a different branch can convey a second portion of the light to another optical spectrometer. The first spectrometer can be relatively wideband to analyze a relative wide spectral segment and the other spectrometer can be high dispersion to measure minor concentrations. The apparatus can have a plurality of spectrometers with distinct and/or complementary capabilities, and can include an inductively coupled plasma mass spectrometer and data and instructions in tangible media operable to obtain a synergistic composition analysis based on optical spectra and ion mass to charge ratio peaks from the mass spectrometer.

Abstract: Apparatus for laser induced ablation spectroscopy (LIBS) is disclosed. An apparatus can have a computer, a pulsed laser and a lightguide fiber bundle that is subdivided into branches. One branch can convey a first portion of the light to a first optical spectrometer and a different branch can convey a second portion of the light to another optical spectrometer. The first spectrometer can be relatively wideband to analyze a relative wide spectral segment and the other spectrometer can be high dispersion to measure minor concentrations. The apparatus can have a plurality of spectrometers with distinct and/or complementary capabilities, and can include an inductively coupled plasma mass spectrometer and data and instructions in tangible media operable to obtain a synergistic composition analysis based on optical spectra and ion mass to charge ratio peaks from the mass spectrometer.

Abstract: Methods for laser induced ablation spectroscopy (LIBS) are disclosed. Light from laser ablation can be gathered into a lightguide fiber bundle that is subdivided into branches. One branch can convey a first portion of the light to a broadband spectrometer operable to analyze a relatively wide spectral segment, and a different branch can convey a second portion of the light to a high dispersion spectrometer operable to measure minor concentrations and/or trace elements. Emissions can be analyzed using a plurality of spectrometers having distinct and/or complementary capabilities, and with a synergistic method using inductively coupled plasma mass spectrometry.

Abstract: Methods of liquid and solid materials analysis by laser induced ablation spectroscopy are disclosed. The liquid and solid materials are analyzed in an instrument having one pulsed laser to produce emissive plasma plumes and ablate solid material. Liquid phase samples are aerosolized before streaming to an analysis zone where they are dissociated into a plasma plume. A large number of sites within solid phase sample structures and be analyzed using a movable x-y-z stage and displayed in a chemical map.

Abstract: Methods for laser induced ablation spectroscopy (LIBS) are disclosed. Light from laser ablation can be gathered into a lightguide fiber bundle that is subdivided into branches. One branch can convey a first portion of the light to a broadband spectrometer operable to analyze a relatively wide spectral segment, and a different branch can convey a second portion of the light to a high dispersion spectrometer operable to measure minor concentrations and/or trace elements. Emissions can be analyzed using a plurality of spectrometers having distinct and/or complementary capabilities, and with a synergistic method using inductively coupled plasma mass spectrometry.

Abstract: Portable instruments for analyzing elemental composition of liquid and solid phase materials by laser induced ablation spectroscopy are disclosed. The optical path of a single pulsed laser beam in the instrument is directed to a position depending on the phase of the sample material. Liquid phase samples are aerosolized before streaming to an analysis zone where they are dissociated in a plasma plume. A wide range of physical and chemical characteristics of liquid materials can be analyzed by the instruments. A large number of sites within solid phase sample structures are analyzed using a movable x-y-z stage in the instrument and the results are displayed in a chemical map.

Abstract: A method and apparatus for analyzing one or more elements of targeted moving food surfaces uses laser-induced breakdown spectroscopy to detect the presence, absence, or amount of an element on a heterogeneous surface of an object, including surfaces of food products. A laser is used to quantify an element concentration without destroying the object. The method can be configured to include an automated on-line system comprising a closed-loop feedback control system operable to select a predetermined concentration.

Abstract: A liquid sampling, atmospheric pressure, glow discharge (LS-APGD) device as well as systems that incorporate the device and methods for using the device and systems are described. The LS-APGD includes a hollow capillary for delivering an electrolyte solution to a glow discharge space. The device also includes a counter electrode in the form of a second hollow capillary that can deliver the analyte into the glow discharge space. A voltage across the electrolyte solution and the counter electrode creates the microplasma within the glow discharge space that interacts with the analyte to move it to a higher energy state (vaporization, excitation, and/or ionization of the analyte).

Abstract: Methods for laser induced ablation spectroscopy are disclosed. A position sensor, and position motors can move a sample stage in three independent spatial coordinate directions, and a stage position control circuit can move an analysis sample site to selected coordinate positions for ablation. Light from laser ablation can be gathered into a lightguide fiber bundle that is subdivided into branches. One branch can convey a first portion of the light to a broadband spectrometer operable to analyze a relatively wide spectral segment, and a different branch can convey a second portion of the light to a high dispersion spectrometer operable to measure minor concentrations and/or trace elements. Emissions can be simultaneously analyzed in various ways using a plurality of spectrometers having distinct and/or complementary capabilities, and isotope analysis of a sample can be performed.

Abstract: One-dimensional nanostructures having uniform diameters of less than approximately 200 nm. These inventive nanostructures, which we refer to as “nanowires”, include single-crystalline homostructures as well as heterostructures of at least two single-crystalline materials having different chemical compositions. Because single-crystalline materials are used to form the heterostructure, the resultant heterostructure will be single-crystalline as well. The nanowire heterostructures are generally based on a semiconducting wire wherein the doping and composition are controlled in either the longitudinal or radial directions, or in both directions, to yield a wire that comprises different materials. Examples of resulting nanowire heterostructures include a longitudinal heterostructure nanowire (LOHN) and a coaxial heterostructure nanowire (COHN).

Abstract: A method and apparatus for analyzing one or more elements of targeted moving snack food surfaces uses laser-induced breakdown spectroscopy to detect the presence, absence, or amount of an element on a heterogeneous surface, including seasoned and ready-to-eat snack foods. A laser is used to quantify the element concentration without destroying the targeted sample. An automated on-line system may be integrated into the method to create a closed-loop feedback control system, adjusting the concentration as desired.

Abstract: A liquid sampling, atmospheric pressure, glow discharge (LS-APGD) device as well as systems that incorporate the device and methods for using the device and systems are described. The LS-APGD includes a hollow capillary for delivering an electrolyte solution to a glow discharge space. The device also includes a counter electrode in the form of a second hollow capillary that can deliver the analyte into the glow discharge space. A voltage across the electrolyte solution and the counter electrode creates the microplasma within the glow discharge space that interacts with the analyte to move it to a higher energy state (vaporization, excitation, and/or ionization of the analyte).

Abstract: A liquid sampling, atmospheric pressure, glow discharge (LS-APGD) device as well as systems that incorporate the device and methods for using the device and systems are described. The LS-APGD includes a hollow capillary for delivering an electrolyte solution to a glow discharge space. The device also includes a counter electrode in the form of a second hollow capillary that can deliver the analyte into the glow discharge space. A voltage across the electrolyte solution and the counter electrode creates the microplasma within the glow discharge space that interacts with the analyte to move it to a higher energy state (vaporization, excitation, and/or ionization of the analyte).

Abstract: A method and apparatus for analyzing one or more elements of targeted moving snack food surfaces uses laser-induced breakdown spectroscopy to detect the presence, absence, or amount of an element on a heterogeneous surface, including seasoned and ready-to-eat snack foods. A laser is used to quantify the element concentration without destroying the targeted sample. An automated on-line system may be integrated into the method to create a closed-loop feedback control system, adjusting the concentration as desired.

Abstract: A liquid sampling, atmospheric pressure, glow discharge (LS-APGD) device as well as systems that incorporate the device and methods for using the device and systems are described. The LS-APGD includes a hollow capillary for delivering an electrolyte solution to a glow discharge space. The device also includes a counter electrode in the form of a second hollow capillary that can deliver the analyte into the glow discharge space. A voltage across the electrolyte solution and the counter electrode creates the microplasma within the glow discharge space that interacts with the analyte to move it to a higher energy state (vaporization, excitation, and/or ionization of the analyte).

Abstract: Provided are laser induced breakdown spectroscopy (LIBS) devices. Embodiments of the devices are configured to obtain a spatial resolution of 10 ?m or less. Also provided are methods of using the subject LIBS devices to determine whether one or more elements of interest are present in a target sample. The devices and methods find use in a variety of applications, e.g., submicron and nanoscale chemical analysis applications.

Abstract: One-dimensional nanostructures having uniform diameters of less than approximately 200 nm. These inventive nanostructures, which we refer to as “nanowires”, include single-crystalline homostructures as well as heterostructures of at least two single-crystalline materials having different chemical compositions. Because single-crystalline materials are used to form the heterostructure, the resultant heterostructure will be single-crystalline as well. The nanowire heterostructures are generally based on a semiconducting wire wherein the doping and composition are controlled in either the longitudinal or radial directions, or in both directions, to yield a wire that comprises different materials. Examples of resulting nanowire heterostructures include a longitudinal heterostructure nanowire (LOHN) and a coaxial heterostructure nanowire (COHN).