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Sample records for breakdown spectroscopy analysis

  1. Analysis of Pulverized Coal by Laser-Induced Breakdown Spectroscopy

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Laser-induced breakdown spectroscopy (LIBS) has been used to detect atomic species in various environments. The quantitative analysis (C, H, O, N and S) of representative coal samples are being carried out with LIBS, and the effects of particle size are analyzed.A powerful pulse Nd:YAG laser is focused on the coal sample at atmosphere pressure, and the emission spectra from laser-induced plasmas are measured by time-resolved spectroscopy, and the intensity of analyzed spectral lines is obtained through observing the laser plasma with a delay time of 0.4μs. The experimental results show that the slope of calibration curve is nearly 1 when the concentration of the analyzed element is relatively low, and the slope of curve is nearly 0.5 when the concentration of C is higher than other elements. In addition, using the calibration-free model without self-absorption effect, the results show that the decreasing of particle size leads to an increase of the plasma temperature.

  2. Fast analysis of wood preservers using laser induced breakdown spectroscopy

    Science.gov (United States)

    Uhl, A.; Loebe, K.; Kreuchwig, L.

    2001-06-01

    Laser-induced breakdown spectroscopy (LIBS) is used for the investigation of wood preservers in timber and in furniture. Both experiments in laboratory and practical applications in recycling facilities and on a building site prove the new possibilities for the fast detection of harmful agents in wood. A commercial system was developed for mobile laser-plasma-analysis as well as for industrial use in sorting plants. The universal measuring principle in combination with an Echelle optics permits real simultaneous multi-element-analysis in the range of 200-780 nm with a resolution of a few picometers. It enables the user to detect main and trace elements in wood within a few seconds, nearly independent of the matrix, knowing that different kinds of wood show an equal elemental composition. Sample preparation is not required. The quantitative analysis of inorganic wood preservers (containing, e.g. Cu, Cr, B, As, Pb, Hg) has been performed exactly using carbon as reference element. It can be shown that the detection limits for heavy metals in wood are in the ppm-range. Additional information is given concerning the quantitative analysis. Statistical data, e.g. the standard deviation (S.D.), were determined and calibration curves were used for each particular element. A comparison between ICP-AES and LIBS is given using depth profile correction factors regarding the different penetration depths with respect to the different volumes in wood analyzed by both analytical methods.

  3. Independent component analysis classification of laser induced breakdown spectroscopy spectra

    Energy Technology Data Exchange (ETDEWEB)

    Forni, Olivier, E-mail: olivier.forni@irap.omp.eu [Université de Toulouse, UPS-OMP, Institut de Recherche en Astrophysiqe et Planétologie, Toulouse (France); CNRS, IRAP, 9, av. Colonel Roche, BP 44346, F-31028 Cedex 4, Toulouse (France); Maurice, Sylvestre, E-mail: sylvestre.maurice@irap.omp.eu [Université de Toulouse, UPS-OMP, Institut de Recherche en Astrophysiqe et Planétologie, Toulouse (France); CNRS, IRAP, 9, av. Colonel Roche, BP 44346, F-31028 Cedex 4, Toulouse (France); Gasnault, Olivier, E-mail: olivier.gasnault@irap.omp.eu [Université de Toulouse, UPS-OMP, Institut de Recherche en Astrophysiqe et Planétologie, Toulouse (France); CNRS, IRAP, 9, av. Colonel Roche, BP 44346, F-31028 Cedex 4, Toulouse (France); Wiens, Roger C., E-mail: rwiens@lanl.gov [Space Remote Sensing, Los Alamos National Laboratory, Los Alamos, NM 87544 (United States); Cousin, Agnès, E-mail: acousin@lanl.gov [Université de Toulouse, UPS-OMP, Institut de Recherche en Astrophysiqe et Planétologie, Toulouse (France); CNRS, IRAP, 9, av. Colonel Roche, BP 44346, F-31028 Cedex 4, Toulouse (France); Chemical Division, Los Alamos National Laboratory, Los Alamos, NM 87544 (United States); Clegg, Samuel M., E-mail: sclegg@lanl.gov [Chemical Division, Los Alamos National Laboratory, Los Alamos, NM 87544 (United States); Sirven, Jean-Baptiste, E-mail: jean-baptiste.sirven@cea.f [CEA Saclay, DEN/DPC/SCP, 91191 Cedex, Gif sur Yvette (France); Lasue, Jérémie, E-mail: jeremie.lasue@irap.omp.eu [Université de Toulouse, UPS-OMP, Institut de Recherche en Astrophysiqe et Planétologie, Toulouse (France); CNRS, IRAP, 9, av. Colonel Roche, BP 44346, F-31028 Cedex 4, Toulouse (France)

    2013-08-01

    The ChemCam instrument on board Mars Science Laboratory (MSL) rover uses the laser-induced breakdown spectroscopy (LIBS) technique to remotely analyze Martian rocks. It retrieves spectra up to a distance of seven meters to quantify and to quantitatively analyze the sampled rocks. Like any field application, on-site measurements by LIBS are altered by diverse matrix effects which induce signal variations that are specific to the nature of the sample. Qualitative aspects remain to be studied, particularly LIBS sample identification to determine which samples are of interest for further analysis by ChemCam and other rover instruments. This can be performed with the help of different chemometric methods that model the spectra variance in order to identify a the rock from its spectrum. In this paper we test independent components analysis (ICA) rock classification by remote LIBS. We show that using measures of distance in ICA space, namely the Manhattan and the Mahalanobis distance, we can efficiently classify spectra of an unknown rock. The Mahalanobis distance gives overall better performances and is easier to manage than the Manhattan distance for which the determination of the cut-off distance is not easy. However these two techniques are complementary and their analytical performances will improve with time during MSL operations as the quantity of available Martian spectra will grow. The analysis accuracy and performances will benefit from a combination of the two approaches. - Highlights: • We use a novel independent component analysis method to classify LIBS spectra. • We demonstrate the usefulness of ICA. • We report the performances of the ICA classification. • We compare it to other classical classification schemes.

  4. Analysis of fresco by laser induced breakdown spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Caneve, L., E-mail: luisa.caneve@enea.i [ENEA, CR Frascati, Via E. Fermi 45, 00044 Frascati (Italy); Diamanti, A. [Universita ' Tor Vergata' , Dipartimento di Scienze e Tecnologie Chimiche, via della Ricerca Scientifica 1, 00133 Roma (Italy); Grimaldi, F. [ENEA, CR Frascati, Via E. Fermi 45, 00044 Frascati (Italy); Palleschi, G. [Universita ' Tor Vergata' , Dipartimento di Scienze e Tecnologie Chimiche, via della Ricerca Scientifica 1, 00133 Roma (Italy); Spizzichino, V. [ENEA, CR Frascati, Via E. Fermi 45, 00044 Frascati (Italy); Valentini, F. [Universita ' Tor Vergata' , Dipartimento di Scienze e Tecnologie Chimiche, via della Ricerca Scientifica 1, 00133 Roma (Italy)

    2010-08-15

    The laser-based techniques have been shown to be a very powerful tool for artworks characterization and are used in the field of cultural heritage for the offered advantages of minimum invasiveness, in situ applicability and high sensitivity. Laser induced breakdown spectroscopy, in particular, has been applied in this field to many different kinds of ancient materials with successful results. In this work, a fragment of a Roman wall painting from the archaeological area of Pompeii has been investigated by LIBS. The sample elemental composition resulting from LIBS measurements suggested the presence of certain pigments. The ratio of the intensities of different lines related to some characteristic elements is proposed as an indicator for pigment recognition. The depth profiling permitted to put in evidence the presence of successive paint layers with different compositions. A comparison with the results obtained by the microscopy inspection of the sample has been done.

  5. Analysis of fresco by laser induced breakdown spectroscopy

    Science.gov (United States)

    Caneve, L.; Diamanti, A.; Grimaldi, F.; Palleschi, G.; Spizzichino, V.; Valentini, F.

    2010-08-01

    The laser-based techniques have been shown to be a very powerful tool for artworks characterization and are used in the field of cultural heritage for the offered advantages of minimum invasiveness, in situ applicability and high sensitivity. Laser induced breakdown spectroscopy, in particular, has been applied in this field to many different kinds of ancient materials with successful results. In this work, a fragment of a Roman wall painting from the archaeological area of Pompeii has been investigated by LIBS. The sample elemental composition resulting from LIBS measurements suggested the presence of certain pigments. The ratio of the intensities of different lines related to some characteristic elements is proposed as an indicator for pigment recognition. The depth profiling permitted to put in evidence the presence of successive paint layers with different compositions. A comparison with the results obtained by the microscopy inspection of the sample has been done.

  6. Elemental Analysis of Soils by Laser Induced Breakdown Spectroscopy

    Science.gov (United States)

    Gondal, Mohammed Ashraf; Dastageer, Mohamed A.

    The chemical and elemental composition of soil is very complex as it contains many constituents like minerals, organic matters, living organisms, fossils, air and water. Considering the diversity of soil contents, quality and usability, a systematic scientific study on the elemental and chemical composition of soil is very important. In order to study the chemical composition of soil, Laser induced breakdown spectroscopy (LIBS) has been applied recently. The important features of LIBS system and its applications for the measurement of nutrients in green house soil, on-line monitoring of remediation process of chromium polluted soil, determination of trace elements in volcanic erupted soil samples collected from ancient cenozoic lava eruption sites and detection of toxic metals in Gulf war oil spill contaminated soil using LIBS are described in this chapter.

  7. Multivariate Analysis of Laser-Induced Breakdown Spectroscopy for Discrimination between Explosives and Plastics

    Institute of Scientific and Technical Information of China (English)

    WANG Qian-Qian; LIU Kai; ZHAO Hua

    2012-01-01

    A method to distinguish explosives from plastics using laser-induced breakdown spectroscopy is discussed. A model for classification with cross-validation theory is built based on the partial least-square discriminant analysis method. Seven types of plastics and one explosive are used as samples to test the model. The experimental results demonstrate that laser-induced breakdown spectroscopy has the capacity to discriminate explosives from plastics combined with chemometrics methods. The results could be useful for prospective research of laser-induced breakdown spectroscopy on the differentiation of explosives and other materials.%A method to distinguish explosives from plastics using laser-induced breakdown spectroscopy is discussed.A model for classification with cross-validation theory is built based on the partial least-square discriminant analysis method.Seven types of plastics and one explosive are used as samples to test the model.The experimental results demonstrate that laser-induced breakdown spectroscopy has the capacity to discriminate explosives from plastics combined with chemometrics methods.The results could be useful for prospective research of laser-induced breakdown spectroscopy on the differentiation of explosives and other materials.

  8. Analysis of bakery products by laser-induced breakdown spectroscopy.

    Science.gov (United States)

    Bilge, Gonca; Boyacı, İsmail Hakkı; Eseller, Kemal Efe; Tamer, Uğur; Çakır, Serhat

    2015-08-15

    In this study, we focused on the detection of Na in bakery products by using laser-induced breakdown spectroscopy (LIBS) as a quick and simple method. LIBS experiments were performed to examine the Na at 589 nm to quantify NaCl. A series of standard bread sample pellets containing various concentrations of NaCl (0.025-3.5%) were used to construct the calibration curves and to determine the detection limits of the measurements. Calibration graphs were drawn to indicate functions of NaCl and Na concentrations, which showed good linearity in the range of 0.025-3.5% NaCl and 0.01-1.4% Na concentrations with correlation coefficients (R(2)) values greater than 0.98 and 0.96. The obtained detection limits for NaCl and Na were 175 and 69 ppm, respectively. Performed experimental studies showed that LIBS is a convenient method for commercial bakery products to quantify NaCl concentrations as a rapid and in situ technique.

  9. Micro spatial analysis of seashell surface using laser-induced breakdown spectroscopy and Raman spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Yuan; Li, Yuandong; Li, Ying [Optics and Optoelectronics Lab, Ocean University of China, Qingdao 266100 (China); Wang, Yangfan; Wang, Shi; Bao, Zhenmin [Life Science College, Ocean University of China, Qingdao 266003 (China); Zheng, Ronger, E-mail: rzheng@ouc.edu.cn [Optics and Optoelectronics Lab, Ocean University of China, Qingdao 266100 (China)

    2015-08-01

    The seashell has been studied as a proxy for the marine researches since it is the biomineralization product recording the growth development and the ocean ecosystem evolution. In this work a hybrid of Laser Induced Breakdown Spectroscopy (LIBS) and Raman spectroscopy was introduced to the composition analysis of seashell (scallop, bivalve, Zhikong). Without any sample treatment, the compositional distribution of the shell was obtained using LIBS for the element detection and Raman for the molecule recognition respectively. The elements Ca, K, Li, Mg, Mn and Sr were recognized by LIBS; the molecule carotene and carbonate were identified with Raman. It was found that the LIBS detection result was more related to the shell growth than the detection result of Raman. The obtained result suggested the shell growth might be developing in both horizontal and vertical directions. It was indicated that the LIBS–Raman combination could be an alternative way for the shell researches. - Highlights: • A LIBS–Raman hybrid system was developed. • A seashell has been analyzed for the elementary and molecular distribution with a system. • The shell growth development was studied on the surface and in the depth.

  10. Laser-induced breakdown spectroscopy for real time and online elemental analysis

    CERN Document Server

    Rai, V N; Yueh, Fang-Yu; Singh, J P

    2014-01-01

    Laser-induced breakdown spectroscopy (LIBS) is a laser based diagnostics used to study atomic emission from the expanding plasma plume formed during the laser-matter interaction. It provides valuable information about the composition of the target material. LIBS has proved its potential application in the analysis of impurities, pollutants and toxic elements in various types of matrices of different samples (solid, liquid and gases), even those present under difficult and harsh environmental conditions. This article reviews some recent developments in the field, and its wide application in various fields of research and analysis.

  11. Application of Handheld Laser-Induced Breakdown Spectroscopy (LIBS) to Geochemical Analysis.

    Science.gov (United States)

    Connors, Brendan; Somers, Andrew; Day, David

    2016-05-01

    While laser-induced breakdown spectroscopy (LIBS) has been in use for decades, only within the last two years has technology progressed to the point of enabling true handheld, self-contained instruments. Several instruments are now commercially available with a range of capabilities and features. In this paper, the SciAps Z-500 handheld LIBS instrument functionality and sub-systems are reviewed. Several assayed geochemical sample sets, including igneous rocks and soils, are investigated. Calibration data are presented for multiple elements of interest along with examples of elemental mapping in heterogeneous samples. Sample preparation and the data collection method from multiple locations and data analysis are discussed.

  12. Extracting coal ash content from laser-induced breakdown spectroscopy (LIBS) spectra by multivariate analysis.

    Science.gov (United States)

    Yao, Shunchun; Lu, Jidong; Dong, Meirong; Chen, Kai; Li, Junyan; Li, Jun

    2011-10-01

    Laser-induced breakdown spectroscopy (LIBS) combined with partial least squares (PLS) analysis has been applied for the quantitative analysis of the ash content of coal in this paper. The multivariate analysis method was employed to extract coal ash content information from LIBS spectra rather than from the concentrations of the main ash-forming elements. In order to construct a rigorous partial least squares regression model and reduce the calculation time, different spectral range data were used to construct partial least squares regression models, and then the performances of these models were compared in terms of the correlation coefficients of calibration and validation and the root mean square errors of calibration and cross-validation. Afterwards, the prediction accuracy, reproducibility, and the limit of detection of the partial least squares regression model were validated with independent laser-induced breakdown spectroscopy measurements of four unknown samples. The results show that a good agreement is observed between the ash content provided by thermo-gravimetric analyzer and the LIBS measurements coupled to the PLS regression model for the unknown samples. The feasibility of extracting coal ash content from LIBS spectra is approved. It is also confirmed that this technique has good potential for quantitative analysis of the ash content of coal.

  13. [Quantitative analysis of alloy steel based on laser induced breakdown spectroscopy with partial least squares method].

    Science.gov (United States)

    Cong, Zhi-Bo; Sun, Lan-Xiang; Xin, Yong; Li, Yang; Qi, Li-Feng; Yang, Zhi-Jia

    2014-02-01

    In the present paper both the partial least squares (PLS) method and the calibration curve (CC) method are used to quantitatively analyze the laser induced breakdown spectroscopy data obtained from the standard alloy steel samples. Both the major and trace elements were quantitatively analyzed. By comparing the results of two different calibration methods some useful results were obtained: for major elements, the PLS method is better than the CC method in quantitative analysis; more importantly, for the trace elements, the CC method can not give the quantitative results due to the extremely weak characteristic spectral lines, but the PLS method still has a good ability of quantitative analysis. And the regression coefficient of PLS method is compared with the original spectral data with background interference to explain the advantage of the PLS method in the LIBS quantitative analysis. Results proved that the PLS method used in laser induced breakdown spectroscopy is suitable for quantitative analysis of trace elements such as C in the metallurgical industry.

  14. Geographical analysis of 'conflict minerals' utilizing laser-induced breakdown spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Hark, Richard R., E-mail: hark@juniata.edu [Department of Chemistry, Juniata College, Huntingdon, PA 16652 (United States); Remus, Jeremiah J. [Department of Electrical and Computer Engineering, Clarkson University, Potsdam, NY 13699 (United States); East, Lucille J. [Applied Spectra, Inc., Fremont, CA 94538 (United States); Harmon, Russell S. [Department of Marine, Earth and Atmospheric Sciences, North Carolina State University, Raleigh, NC 27695 (United States); Wise, Michael A. [Department of Mineral Sciences, Smithsonian Institution, Washington, DC 20013 (United States); Tansi, Benjamin M.; Shughrue, Katrina M. [Department of Chemistry, Juniata College, Huntingdon, PA 16652 (United States); Dunsin, Kehinde S. [Department of Electrical and Computer Engineering, Clarkson University, Potsdam, NY 13699 (United States); Liu, Chunyi [Applied Spectra, Inc., Fremont, CA 94538 (United States)

    2012-08-15

    Laser-induced breakdown spectroscopy (LIBS) offers a means of rapidly distinguishing different geographic sources for a mineral because the LIBS plasma emission spectrum provides information on the chemical composition (i.e. geochemical fingerprint) of a geomaterial. An application of this approach with potentially significant commercial and political importance is the spectral fingerprinting of 'conflict minerals' such as columbite-tantalite ('coltan'). Following a successful pilot study of a columbite-tantalite suite from North America, a more geographically diverse set of 57 samples from 37 locations around the world was analyzed using a commercially available LIBS system. The LIBS spectra were analyzed using advanced multivariate statistical signal processing techniques. Partial least squares discriminant analysis (PLSDA) resulted in a correct place-level geographic classification at success rates above 90%. The possible role of rare-earth elements (REEs) as a factor contributing to the high levels of sample discrimination was explored. These results provide additional evidence that LIBS has the potential to be utilized in the field as a real-time screening tool to discriminate between columbite-tantalite ores of different provenance. - Highlights: Black-Right-Pointing-Pointer Analysis of columbite-tantalite using laser-induced breakdown spectroscopy (LIBS) Black-Right-Pointing-Pointer Chemometric analysis (PLSDA) affords 90-100% correct sample classification. Black-Right-Pointing-Pointer Possible role of rare-earth elements in the high level of sample discrimination.

  15. Application of laser-induced breakdown spectroscopy to the analysis of algal biomass for industrial biotechnology

    Energy Technology Data Exchange (ETDEWEB)

    Porizka, P.; Prochazka, D. [X-ray micro CT and nano CT research group, CEITEC-Central European Institute of Technology, Brno University of Technology, Technicka 3058/10, 616 00 Brno (Czech Republic); Pilat, Z. [Institute of Scientific Instruments of the ASCR v.v.i., Academy of Sciences of the Czech Republic, Kralovopolska 147, Brno 61669 (Czech Republic); Krajcarova, L. [Department of Chemistry, Faculty of Sciences, Masaryk University, Kotlarska 2, Brno 611 37 (Czech Republic); Kaiser, J., E-mail: kaiser@fme.vutbr.cz [X-ray micro CT and nano CT research group, CEITEC-Central European Institute of Technology, Brno University of Technology, Technicka 3058/10, 616 00 Brno (Czech Republic); Malina, R.; Novotny, J. [X-ray micro CT and nano CT research group, CEITEC-Central European Institute of Technology, Brno University of Technology, Technicka 3058/10, 616 00 Brno (Czech Republic); Zemanek, P.; Jezek, J.; Sery, M.; Bernatova, S.; Krzyzanek, V.; Dobranska, K. [Institute of Scientific Instruments of the ASCR v.v.i., Academy of Sciences of the Czech Republic, Kralovopolska 147, Brno 61669 (Czech Republic); Novotny, K. [Department of Chemistry, Faculty of Sciences, Masaryk University, Kotlarska 2, Brno 611 37 (Czech Republic); Trtilek, M. [Photon Systems Instruments, Drasov 470, 664 24 Drasov (Czech Republic); Samek, O. [Institute of Scientific Instruments of the ASCR v.v.i., Academy of Sciences of the Czech Republic, Kralovopolska 147, Brno 61669 (Czech Republic)

    2012-08-15

    We report on the application of laser-induced breakdown spectroscopy (LIBS) to the determination of elements distinctive in terms of their biological significance (such as potassium, magnesium, calcium, and sodium) and to the monitoring of accumulation of potentially toxic heavy metal ions in living microorganisms (algae), in order to trace e.g. the influence of environmental exposure and other cultivation and biological factors having an impact on them. Algae cells were suspended in liquid media or presented in a form of adherent cell mass on a surface (biofilm) and, consequently, characterized using their spectra. In our feasibility study we used three different experimental arrangements employing double-pulse LIBS technique in order to improve on analytical selectivity and sensitivity for potential industrial biotechnology applications, e.g. for monitoring of mass production of commercial biofuels, utilization in the food industry and control of the removal of heavy metal ions from industrial waste waters. - Highlights: Black-Right-Pointing-Pointer We realized laser-induced breakdown spectroscopy (LIBS) analysis of algal biomass. Black-Right-Pointing-Pointer We used water jet setup, bulk liquid arrangement and algal biofilms. Black-Right-Pointing-Pointer LIBS analysis of macro- and micro-element concentrations in algae was shown. Black-Right-Pointing-Pointer LIBS can be of assistance in research of sustainable biofuel generation. Black-Right-Pointing-Pointer LIBS can be used in research of algal food applications and bioremediation.

  16. Analysis of antique bronze coins by Laser Induced Breakdown Spectroscopy and multivariate analysis

    Science.gov (United States)

    Bachler, M. Orlić; Bišćan, M.; Kregar, Z.; Jelovica Badovinac, I.; Dobrinić, J.; Milošević, S.

    2016-09-01

    This work presents a feasibility study of applying the Principal Component Analysis (PCA) to data obtained by Laser-Induced Breakdown Spectroscopy (LIBS) with the aim of determining correlation between different samples. The samples were antique bronze coins coated in silver (follis) dated in the Roman Empire period and were made during different rulers in different mints. While raw LIBS data revealed that in the period from the year 286 to 383 CE content of silver was constantly decreasing, the PCA showed that the samples can be somewhat grouped together based on their place of origin, which could be a useful hint when analysing unknown samples. It was also found that PCA can help in discriminating spectra corresponding to ablation from the surface and from the bulk. Furthermore, Partial Least Squares method (PLS) was used to obtain, based on a set of samples with known composition, an estimation of relative copper concentration in studied ancient coins. This analysis showed that copper concentration in surface layers ranged from 83% to 90%.

  17. Note: A novel technique for analysis of aqueous solutions by laser-induced breakdown spectroscopy.

    Science.gov (United States)

    Rusak, D A; Anthony, T P; Bell, Z T

    2015-11-01

    Surface-enhanced Raman spectroscopy (SERS) substrates typically consist of gold or silver nanoparticles deposited on a non-conductive substrate. In Raman spectroscopy, the nanoparticles produce an enhancement of the electromagnetic field which, in turn, leads to greater electronic excitation of molecules in the local environment. Here, we show that these same surfaces can be used to enhance the signal-to-noise ratio obtained in laser-induced breakdown spectroscopy of aqueous solutions. In this case, the SERS substrates not only lower breakdown thresholds and lead to more efficient plasma initiation but also provide an appropriately wettable surface for the deposition of the liquid. We refer to this technique as surface-enhanced laser-induced breakdown spectroscopy.

  18. Quantitative analysis of metformin in antidiabetic tablets by laser-induced breakdown spectroscopy

    Science.gov (United States)

    Contreras, U.; Ornelas-Soto, N.; Meneses-Nava, M. A.; Barbosa-García, O.; López-de-Alba, P. L.; López-Martínez, L.

    2011-09-01

    Nowadays the production of counterfeit and low quality drugs affects human health and generates losses to pharmaceutical industries and tax revenue losses to government. Currently there are several methods for pharmaceutical product analysis; nevertheless, most of them depend on complex and time consuming steps such as sample preparation. In contrast to conventional methods, Laser-induced breakdown spectroscopy (LIBS) is evaluated as a potential analytical technique for the rapid screening and quality control of anti-diabetic solid formulations. In this paper authors propose a simple method to analyze qualitatively and quantitatively Active Pharmaceutical Ingredients (APIs) such as Metformin hydrochloride. The authors used ten nanosecond duration pulses (FWHM) from a Nd:YAG laser produces the induced breakdown for the analysis. Light is collected and focused into a Cerny-Turner spectrograph and dispersed into an ICCD camera for its detection. We used atomic emissions from Chlorine atoms present only in APIs as analyte signal. The analysis was improved using Bromine as internal standard. Linear calibration curves from synthetic samples were prepared achieving linearity higher than 99%. Our results were compared with HPLC results and validation was performed by statistical methods. The validation analysis suggests that both methods have no significant differences i.e., the proposed method can be implemented for monitoring the pharmaceutical production process in-situ in real time or for inspection and recognition of authenticity.

  19. Quantitative analysis of impurities in aluminum alloys by laser-induced breakdown spectroscopy without internal calibration

    Institute of Scientific and Technical Information of China (English)

    LI Hong-kun; LIU Ming; CHEN Zhi-jiang; LI Run-hua

    2008-01-01

    To develop a fast and sensitive alloy elemental analysis method, a laser-induced breakdown spectroscopy(LIBS) system was established and used to carry out quantitative analysis of impurities in aluminum alloys in air at atmospheric pressure. A digital storage oscilloscope was used as signal recording instrument, instead of traditional gate integrator or Boxcar averager, to reduce the cost of the whole system. Linear calibration curves in the concentration range of 4×10-5-10-2 are built for Mg, Cr, Mn, Cu and Zn using absolute line intensity without internal calibrations. Limits of detection for these five elements in aluminum alloy are determined to be (2-90)×10-6. It is demonstrated that LIBS can provide quantitative trace elemental analysis in alloys even without internal calibration. This approach is easy to use in metallurgy industries and relative research fields.

  20. Laser Induced Breakdown Spectroscopy applications to meteorites: Chemical analysis and composition profiles

    Science.gov (United States)

    Dell'Aglio, M.; De Giacomo, A.; Gaudiuso, R.; Pascale, O. De; Senesi, G. S.; Longo, S.

    2010-12-01

    A fast procedure for chemical analysis of different meteorites is presented, based on LIBS (Laser Induced Breakdown Spectroscopy). The technique is applied to several test cases (Dhofar 019, Dhofar 461, Sahara 98222, Toluca, Sikhote Alin and Campo del Cielo) and can be useful for rapid meteorite identification providing geologists with specific chemical information for meteorite classification. Concentration profiles of Fe, Ni and Co are simultaneously detected across the Widmanstätten structure of the iron meteorite Toluca with a view to determining cooling rates. The LIBS analysis of meteorites is also used as a laboratory test for analogous studies on the respective parent bodies (Mars, asteroids) in space exploration missions where one clear advantage of the proposed technique is that no direct contact with the sample is required.

  1. Multivariate analysis of laser-induced breakdown spectroscopy chemical signatures for geomaterial classification

    Energy Technology Data Exchange (ETDEWEB)

    Gottfried, Jennifer L., E-mail: jennifer.gottfried@us.army.mi [US Army Research Laboratory, Aberdeen Proving Ground, MD 21005-5069 (United States); Harmon, Russell S. [ARL Army Research Office, PO Box 12211, Research Triangle Park, NC 27709-2211 (United States); De Lucia, Frank C.; Miziolek, Andrzej W. [US Army Research Laboratory, Aberdeen Proving Ground, MD 21005-5069 (United States)

    2009-10-15

    A large suite of natural carbonate, fluorite and silicate geological materials was studied using laser-induced breakdown spectroscopy (LIBS). Both single- and double-pulse LIBS spectra were acquired using close-contact benchtop and standoff (25 m) LIBS systems. Principal components analysis (PCA) and partial least squares discriminant analysis (PLS-DA) were used to identify the distinguishing characteristics of the geological samples and to classify the materials. Excellent discrimination was achieved with all sample types using PLS-DA and several techniques for improving sample classification were identified. The laboratory double-pulse LIBS system did not provide any advantage for sample classification over the single-pulse LIBS system, except in the case of the soil samples. The standoff LIBS system provided comparable results to the laboratory systems. This work also demonstrates how PCA can be used to identify spectral differences between similar sample types based on minor impurities.

  2. Quantitative analysis of Cu and Co adsorbed on fish bones via laser-induced breakdown spectroscopy

    Science.gov (United States)

    Rezk, R. A.; Galmed, A. H.; Abdelkreem, M.; Ghany, N. A. Abdel; Harith, M. A.

    2016-09-01

    In the present work, laser-induced breakdown spectroscopy (LIBS) has been applied for qualitative and quantitative analysis of heavy metals adsorbed by fish bones. Fish bones were used as a natural and low cost heavy metal sorbent (mainly Cu and Co) from synthetic wastewater. The removal efficiency of the adsorbent was studied as a function of initial metal concentration and pH value. Optimal experimental conditions were evaluated for improving the sensitivity of LIBS technique through parametric dependence studies. Furthermore, calibration curves were constructed based on X-ray fluorescence (XRF) analysis technique, whereas, the limits of detection (LOD) for Cu and Co were calculated. The results were validated by comparing LIBS data with those obtained by XRF spectrometry. The results of the two techniques are strongly correlated which verified the feasibility of using LIBS to detect traces of heavy metals adsorbed from wastewater by fish bones. This study reflects the potential of using LIBS in environmental applications.

  3. Laser-induced breakdown spectroscopy: A versatile technique of elemental analysis and its applications

    CERN Document Server

    Rai, V N

    2014-01-01

    This paper reviews the state of art technology of laser induced breakdown spectroscopy (LIBS). Research on LIBS is gaining momentum in the field of instrumentation and data analysis technique due to its wide application in various field particularly in environmental monitoring and in industry. The main focus is on its miniaturization for field application and on increasing its sensitivity. The sensitivity of LIBS has been increased by confining the laser produced plasma using external magnetic field as well as using two successive laser pulse excitation of plasma. LIBS has capability for simultaneous multi element determination, localized microanalysis, surface analysis and has been used successfully for determination and identification of hazardous explosive and biological samples. Experimental findings of LIBS study in different applications have been discussed.

  4. A Hydrogel's Formation Device for Quick Analysis of Liquid Samples Using Laser-Induced Breakdown Spectroscopy

    Science.gov (United States)

    Guo, Guangmeng; Wang, Jie; Bian, Fang; Tian, Di; Fan, Qingwen

    2016-06-01

    The laser-induced breakdown spectroscopy technique has irreplaceable advantages in the field of detection due to its multi-phase specimen detection ability. The development of the LIBS technique for liquid analysis is obstructed by its inherent drawbacks like the surface ripples and extinction of emitted intensity, which make it unpractical. In this work, an in-situ hydrogel formation sampling device was designed and used the hydrogel as the detection phase of LIBS for Cu, Cr and Al in an aqueous solution. With the measured amount of resin placed in the device, the formed hydrogel could be obtained within 20 s after putting the device into water solution. The formed hydrogel could be directly analyzed by LIBS and reflect the elemental information of the water sample. The prominent performance made this hydrogel's formation device especially suitable for quick in-situ environmental liquid analysis using LIBS.

  5. Analysis of plutonium oxide surrogate residue using laser-induced breakdown spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Zheng Hongbo [Department of Applied Physics, College of Science, Nanjing University of Technology, Nanjing (China); Yueh, F.Y.; Miller, Tracy [Institute for Clean Energy Technology (ICET), Mississippi State University, Starkville, MS 39759-7704 (United States); Singh, Jagdish P. [Institute for Clean Energy Technology (ICET), Mississippi State University, Starkville, MS 39759-7704 (United States)], E-mail: singh@icet.msstate.edu; Zeigler, Kristine E.; Marra, James C. [Savannah River National Laboratory (SRNL), Aiken, SC 29808 (United States)

    2008-09-15

    Laser-induced breakdown spectroscopy was used to determine the elemental composition of a CeO{sub 2} composite powder for process control verification during lanthanide borosilicate glass fabrication. Cerium oxide is used as a surrogate for plutonium oxide, which along with other canister contents will be combined with frit to make glass. Laser-induced breakdown spectroscopy data for the composition of the CeO{sub 2} batch containing concentrations of Ce, Cr, Si, Fe, Ta, Ni, Zn, Al Mg, Gd, and W were quantitatively determined from laser-induced breakdown spectroscopy spectra of both pellet and powder samples. The results of both forms were compared and it was determined that the pellet data gave slightly better precision than the powder sample.

  6. [Application progress of laser-induced breakdown spectroscopy for surface analysis in materials science field].

    Science.gov (United States)

    Zhang, Yong; Jia, Yun-Hai; Chen, Ji-Wen; Liu, Ying; Shen, Xue-Jing; Zhao, Lei; Wang, Shu-Ming; Yu, Hong; Han, Peng-Cheng; Qu, Hua-Yang; Liu, Shao-Zun

    2012-06-01

    As a truly surface analytical tool, laser-induced breakdown spectroscopy (LIBS) was developed in recent ten years, and in this paper, fundamental theory, instrumentation and it's applications in material science are reviewed in detail. Application progress of elemental distribution and depth profile analysis are mainly discussed in the field of metallurgy, semiconductor and electronical materials at home and abroad. It is pointed out that the pulse energy, ambient gas and it's pressure, and energy distribution of laser beam strongly influence spatial and depth resolution, and meanwhile a approach to improving resolution considering analytical sensitivity is provided. Compared with traditional surface analytical methods, the advantage of LIBS is very large scanning area, high analytical speed, and that conducting materials or non-conducting materials both can be analyzed. It becomes a powerful complement of traditional surface analytical tool.

  7. Double-pulse laser-induced breakdown spectroscopy analysis of scales from petroleum pipelines

    Energy Technology Data Exchange (ETDEWEB)

    Cavalcanti, G.H. [Physics Department of University Federal Fluminense, Av. Gal. Milton Tavares de Souza, s/n" o – CEP 24210-346 – Niterói, Rio de Janeiro (Brazil); Rocha, A.A. [Department of Analytical Chemistry of the Fluminense Federal University (UFF), Niterói, Rio de Janeiro CEP: 24020-141 (Brazil); Damasceno, R.N. [Biomass and Water Research Center of the Fluminense Federal University (NAB/UFF), Niterói, Rio de Janeiro (Brazil); Legnaioli, S.; Lorenzetti, G.; Pardini, L. [Institute of Chemistry of Organometallic Compounds Of CNR, Research Area of National Research Council, Via G. Moruzzi, 1 — 56124 Pisa (Italy); Palleschi, V., E-mail: vincenzo.palleschi@cnr.it [Institute of Chemistry of Organometallic Compounds Of CNR, Research Area of National Research Council, Via G. Moruzzi, 1 — 56124 Pisa (Italy)

    2013-09-01

    Pipeline scales from the Campos Bay Petroleum Field near Rio de Janeiro, Brazil have been analyzed by both Raman spectroscopy and by laser-induced breakdown spectroscopy (LIBS) using a double-pulse, calibration-free approach. Elements that are characteristic of petroleum (e.g. C, H, N, O, Mg, Na, Fe and V) were detected, in addition to the Ca, Al, and Si which form the matrix of the scale. The LIBS results were compared with the results of micro-Raman spectroscopy, which confirmed the nature of the incrustations inferred by the LIBS analysis. Results of this preliminary study suggest that diffusion of pipe material into the pipeline intake column plays an important role in the growth of scale. Thanks to the simplicity and relative low cost of equipment and to the fact that no special chemical pre-treatment of the samples is needed, LIBS can offer very fast acquisition of data and the possibility of in situ measurements. LIBS could thus represent an alternative or complementary method for the chemical characterization of the scales by comparison to conventional analytical techniques, such as X-ray diffraction or X-ray fluorescence. - Highlights: • Samples of scales from petroleum pipelines were analyzed using double pulse LIBS. • LIBS is proposed as an alternative method to conventional analytical techniques. • The scale growth is influenced by the product of corrosion in the column of production. • The diffusion of pipe material into the inlay is important for the growth of scale.

  8. Study on Cluster Analysis Used with Laser-Induced Breakdown Spectroscopy

    Science.gov (United States)

    He, Li'ao; Wang, Qianqian; Zhao, Yu; Liu, Li; Peng, Zhong

    2016-06-01

    Supervised learning methods (eg. PLS-DA, SVM, etc.) have been widely used with laser-induced breakdown spectroscopy (LIBS) to classify materials; however, it may induce a low correct classification rate if a test sample type is not included in the training dataset. Unsupervised cluster analysis methods (hierarchical clustering analysis, K-means clustering analysis, and iterative self-organizing data analysis technique) are investigated in plastics classification based on the line intensities of LIBS emission in this paper. The results of hierarchical clustering analysis using four different similarity measuring methods (single linkage, complete linkage, unweighted pair-group average, and weighted pair-group average) are compared. In K-means clustering analysis, four kinds of choosing initial centers methods are applied in our case and their results are compared. The classification results of hierarchical clustering analysis, K-means clustering analysis, and ISODATA are analyzed. The experiment results demonstrated cluster analysis methods can be applied to plastics discrimination with LIBS. supported by Beijing Natural Science Foundation of China (No. 4132063)

  9. Ash analysis of flour sample by using laser-induced breakdown spectroscopy

    Science.gov (United States)

    Bilge, Gonca; Sezer, Banu; Eseller, Kemal Efe; Berberoglu, Halil; Koksel, Hamit; Boyaci, Ismail Hakki

    2016-10-01

    Ash content is a measure of total mineral content in flour. It is also an important quality parameter in terms of nutritional labeling as well as processing properties of various cereal products. However, laboratory analysis takes a long time (5-6 h) and results in considerable waste of energy. Therefore, the aim of the study was to develop a new method for ash analysis in wheat flour by using laser induced breakdown spectroscopy (LIBS). LIBS is a multi-elemental, quick and simple spectroscopic method. Unlike basic ash analysis method, it has the potential to analyze a sample in a considerably short time. In the study, wheat flours with different ash contents were analyzed using LIBS and the spectra were evaluated with partial least squares (PLS) method. The results were correlated with the ones taken from standard ash analysis method. Calibration graph showed good linearity with the ash content between 0.48 and 1.39%, and 0.992 coefficient of determination (R2). Limit of detection for ash analysis was calculated as 0.026%. The results indicated that LIBS is a promising and reliable method with high sensitivity for routine ash analysis in flour samples.

  10. Spectral Analysis of Rare Earth Elements using Laser-Induced Breakdown Spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Martin, Madhavi Z [ORNL; Fox, Dr. Richard V [Idaho National Laboratory (INL); Miziolek, Andrzej W [United States Army Research Laboratory; DeLucia, Frank C [United States Army Research Laboratory; Andre, Nicolas O [ORNL

    2015-01-01

    There is growing interest in rapid analysis of rare earth elements (REEs) both due to the need to find new natural sources to satisfy increased demand in their use in various electronic devices, as well as the fact that they are used to estimate actinide masses for nuclear safeguards and nonproliferation. Laser-Induced Breakdown Spectroscopy (LIBS) appears to be a particularly well-suited spectroscopy-based technology to rapidly and accurately analyze the REEs in various matrices at low concentration levels (parts-per-million). Although LIBS spectra of REEs have been reported for a number of years, further work is still necessary in order to be able to quantify the concentrations of various REEs in real-world complex samples. LIBS offers advantages over conventional solution-based radiochemistry in terms of cost, analytical turnaround, waste generation, personnel dose, and contamination risk. Rare earth elements of commercial interest are found in the following three matrix groups: 1) raw ores and unrefined materials, 2) as components in refined products such as magnets, lighting phosphors, consumer electronics (which are mostly magnets and phosphors), catalysts, batteries, etc., and 3) waste/recyclable materials (aka e-waste). LIBS spectra for REEs such as Gd, Nd, and Sm found in rare earth magnets are presented.

  11. Spectral Analysis of Rare Earth Elements using Laser-Induced Breakdown Spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Martin, Madhavi Z [ORNL; Fox, Dr. Richard V [Idaho National Laboratory (INL); Miziolek, Andrzej W [United States Army Research Laboratory; DeLucia, Frank C [United States Army Research Laboratory; Andre, Nicolas O [ORNL

    2015-01-01

    There is growing interest in rapid analysis of rare earth elements (REEs) both due to the need to find new natural sources to satisfy increased demand in their use in various electronic devices, as well as the fact that they are used to estimate actinide masses for nuclear safeguards and nonproliferation. Laser-Induced Breakdown Spectroscopy (LIBS) appears to be a particularly well-suited spectroscopy-based technology to rapidly and accurately analyze the REEs in various matrices at low concentration levels (parts-per-million). Although LIBS spectra of REEs have been reported for a number of years, further work is still necessary in order to be able to quantify the concentrations of various REEs in realworld complex samples. LIBS offers advantages over conventional solution-based radiochemistry in terms of cost, analytical turnaround, waste generation, personnel dose, and contamination risk. Rare earth elements of commercial interest are found in the following three matrix groups: 1) raw ores and unrefined materials, 2) as components in refined products such as magnets, lighting phosphors, consumer electronics (which are mostly magnets and phosphors), catalysts, batteries, etc., and 3) waste/recyclable materials (aka e-waste). LIBS spectra for REEs such as Gd, Nd, and Sm found in rare earth magnets are presented.

  12. Spectral Analysis of Rare Earth Elements using Laser-Induced Breakdown Spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Madhavi Z. Martin; Robert V. Fox; Andrzej W. Miziolek; Frank C. DeLucia, Jr.; Nicolas Andre

    2001-05-01

    There is growing interest in rapid analysis of rare earth elements (REEs) both due to the need to find new natural sources to satisfy increased demand in their use in various electronic devices, as well as the fact that they are used to estimate actinide masses for nuclear safeguards and nonproliferation. Laser-Induced Breakdown Spectroscopy (LIBS) appears to be a particularly well-suited spectroscopy-based technology to rapidly and accurately analyze the REEs in various matrices at low concentration levels (parts-per-million). Although LIBS spectra of REEs have been reported for a number of years, further work is still necessary in order to be able to quantify the concentrations of various REEs in realworld complex samples. LIBS offers advantages over conventional solution-based radiochemistry in terms of cost, analytical turnaround, waste generation, personnel dose, and contamination risk. Rare earth elements of commercial interest are found in the following three matrix groups: 1) raw ores and unrefined materials, 2) as components in refined products such as magnets, lighting phosphors, consumer electronics (which are mostly magnets and phosphors), catalysts, batteries, etc., and 3) waste/recyclable materials (aka e-waste). LIBS spectra for REEs such as Gd, Nd, and Sm found in rare earth magnets are presented.

  13. Laser-induced breakdown spectroscopy analysis of complex silicate minerals--beryl.

    Science.gov (United States)

    McMillan, Nancy J; McManus, Catherine E; Harmon, Russell S; De Lucia, Frank C; Miziolek, Andrzej W

    2006-05-01

    Beryl (Be3Al2Si6O18) is a chemically complex and highly compositionally variable gem-forming mineral found in a variety of geologic settings worldwide. A methodology and analytical protocol were developed for the analysis of beryl by laser-induced breakdown spectroscopy (LIBS) that minimizes the coefficient of variance for multiple analyses of the same specimen. The parameters considered were laser energy/pulse, time delay and crystallographic orientation. Optimal analytical conditions are a laser energy/pulse of 102 mJ and a time delay of 2 micros. Beryl compositions measured parallel and perpendicular to the c axis were identical within analytical error. LIBS analysis of 96 beryls from 16 countries (Afghanistan, Brazil, Canada, China, Colombia, India, Ireland, Italy, Madagascar, Mexico, Mozambique, Namibia, Norway, Russia, Tanzania and United States), Antarctica, and ten US states (AZ, CA, CO, CT, ID, ME, NC, NH, NM and UT) were undertaken to determine whether or not LIBS analysis can be used to determine the provenance of gem beryl.

  14. Calibration-free laser-induced breakdown spectroscopy for quantitative elemental analysis of materials

    Indian Academy of Sciences (India)

    V K Unnikrishnan; K Mridul; R Nayak; K Alti; V B Kartha; C Santhosh; G Gupta; B M Suri

    2012-08-01

    The application of calibration-free laser-induced breakdown spectroscopy (CF-LIBS) for quantitative analysis of materials, illustrated by CF-LIBS applied to a brass sample of known composition, is presented in this paper. The LIBS plasma is produced by a 355 nm pulsed Nd:YAG laser with a pulse duration of 6 ns focussed onto a brass sample in air at atmospheric pressure. The time-resolved atomic and ionic emission lines of Cu and Zn from the LIBS spectra recorded by an Echelle spectrograph coupled with a gated intensified charge coupled detector are used for the plasma characterization and the quantitative analysis of the sample. The time delay where the plasma is optically thin and is also in local thermodynamic equilibrium (LTE), necessary for the elemental analysis of samples from the LIBS spectra, is deduced. An algorithm relating the experimentally measured spectral intensity values with the basic physics of the plasma is developed. Using the algorithm, the Zn and Cu concentratioins in the brass sample are determined. The analytical result obtained from the CF-LIBS technique agree well with the certified valued of the elements in the sample, with an accuracy error < 1%

  15. Laser-induced breakdown spectroscopy analysis of human deciduous teeth samples.

    Science.gov (United States)

    Khalid, Arooj; Bashir, Shazia; Akram, Mahreen; Hayat, Asma

    2015-12-01

    Laser-induced breakdown spectroscopy (LIBS) analysis of human deciduous teeth has been performed by employing Nd:YAG laser (1064 nm, 10 ns) for the evaluation of plasma parameters as well as elemental analysis. The plasma parameters, i.e., electron temperature and electron number density of laser-induced teeth plasma at various fluencies, have been evaluated. Both parameters show an increasing trend up to a certain value of laser fluence, i.e., 2.6 J/cm(2). With further increase in laser fluence up to a value of 3.9 J/cm(2), a decreasing trend is observed which is due to shielding effect. With further increase in laser fluence up to a maximum value of 10.5 J/cm(2), the insignificant changes in plasma parameters are observed which are attributed to saturation phenomenon governed by self-regulating regime. Emission spectroscopy results exhibit that laser fluence is the controlling factor for both plasma parameters. The elemental analysis was also performed at constant laser fluence of 2.6 J/cm(2) by evaluating the variation in detected elemental concentration of Ca, Fe, Sr, Zn, and Pb in three different parts of human teeth, i.e., enamel, dentine, and cementum. The lower concentration of Ca as compared to the standard values of CaCO3 (self-fabricated pellet) reveals that enamel is the most deciduous part of the human teeth. However, at the same time, it is also observed that the highest concentration of micro minerals is also found in enamel, then in dentine, and lowest in cementum. Carious or unhealthy tooth is identified by enhanced concentration of micro minerals (Pb, Sr, Zn, and Fe). The highest concentration of micro minerals as compared to other parts of teeth (dentine and root cementum) and lower concentration of Ca as compared to standard CaCO3 pellet in enamel confirm that enamel is the most deciduous part of the teeth.

  16. Laser induced breakdown spectroscopy for analysis and characterization of degradation pathologies of Roman glasses

    Energy Technology Data Exchange (ETDEWEB)

    Palomar, T. [Instituto de Historia, Centro de Ciencias Humanas y Sociales, CSIC, C/Albasanz 26-28, 28037 Madrid (Spain); Oujja, M., E-mail: m.oujja@iqfr.csic.es [Instituto de Química Física Rocasolano, CSIC, C/Serrano 119, 28006 Madrid (Spain); García-Heras, M.; Villegas, M.A. [Instituto de Historia, Centro de Ciencias Humanas y Sociales, CSIC, C/Albasanz 26-28, 28037 Madrid (Spain); Castillejo, M. [Instituto de Química Física Rocasolano, CSIC, C/Serrano 119, 28006 Madrid (Spain)

    2013-09-01

    The feasibility and possibilities of laser induced breakdown spectroscopy (LIBS) in the full study of non-destructible historic glasses have been explored in the present work. Thirteen Roman glass samples, including seven entire glass beads, from the ancient town of Augusta Emerita (SW Spain) were characterized by LIBS in combination with other conventional techniques, such as scanning electron microscopy/energy dispersive X-ray spectrometry, X-ray fluorescence and ultraviolet–visible spectrophotometry. LIBS stratigraphic analysis, carried out by the application of successive laser pulses on the same spot, has been mainly targeted at characterizing particular features of non-destructible historic glasses, such as bulk chemical composition, surface degradation pathologies (dealkalinization layers and deposits), chromophores, and opacifying elements. The obtained data demonstrate that LIBS can be a useful and alternative technique for spectroscopic studies of historical glasses, especially for those conserved under burial conditions and when it deals with studying non-destructible samples. - Highlights: • Determination of chromophores and opacifiers in non-destructible glass by LIBS • Manganese is determined as principal component of dark deposits. • Antimony appears in all decorations while lead is only present in yellow ones. • Stratigraphic analysis enables the identification of dealkalinization layers.

  17. Quantitative analysis of lead in aqueous solutions by ultrasonic nebulizer assisted laser induced breakdown spectroscopy

    Science.gov (United States)

    Zhong, Shi-Lei; Lu, Yuan; Kong, Wei-Jin; Cheng, Kai; Zheng, Ronger

    2016-08-01

    In this study, an ultrasonic nebulizer unit was established to improve the quantitative analysis ability of laser-induced breakdown spectroscopy (LIBS) for liquid samples detection, using solutions of the heavy metal element Pb as an example. An analytical procedure was designed to guarantee the stability and repeatability of the LIBS signal. A series of experiments were carried out strictly according to the procedure. The experimental parameters were optimized based on studies of the pulse energy influence and temporal evolution of the emission features. The plasma temperature and electron density were calculated to confirm the LTE state of the plasma. Normalizing the intensities by background was demonstrated to be an appropriate method in this work. The linear range of this system for Pb analysis was confirmed over a concentration range of 0-4,150ppm by measuring 12 samples with different concentrations. The correlation coefficient of the fitted calibration curve was as high as 99.94% in the linear range, and the LOD of Pb was confirmed as 2.93ppm. Concentration prediction experiments were performed on a further six samples. The excellent quantitative ability of the system was demonstrated by comparison of the real and predicted concentrations of the samples. The lowest relative error was 0.043% and the highest was no more than 7.1%.

  18. Composition analysis of medieval ceramics by laser-induced breakdown spectroscopy (LIBS)

    Science.gov (United States)

    Genc Oztoprak, B.; Sinmaz, M. A.; Tülek, F.

    2016-05-01

    Laser-induced breakdown spectroscopy (LIBS) technique is expected to be one of the most preferred techniques in archaeology research since it does not disrupt the structural and chemical form of archaeological samples, and it is considered virtually nondestructive analysis method. In this work, LIBS is used for analyses of glaze, paint, and clay of medieval ceramics collected from East Plain Cilicia, Osmaniye Province during archaeological survey. Transparent glazed and colour-painted ceramics of the Islam and Byzantine pottery traditions are analysed to detect distinctive and common features of the chemical compositions of their glazes. The spectral lines of Islamic and Byzantine glazes indicate that their structures are same. However, strontium (Sr) is determined in the transparent glaze of Islamic ceramics. Elemental composition and homogeneity of paint on one of the sample are determined by LIBS analysis. Colour changes are related with composition differences of the paint content in the archaeological ceramic. In addition, the clay classification of archaeological ceramics taken from the Yapılıpınar mounds, Taşlıhöyük mounds, and Örenşehir ancient sites is done using PCA and PLS-DA chemometric techniques. According to the results of the classification, Yapılıpınar mounds terracotta ceramics differ from those of Taşlıhöyük and Örenşehir ancient sites.

  19. Analysis Si/Al ratio in zeolites type FAU by laser induced breakdown spectroscopy (LIBS)

    Science.gov (United States)

    Contreras, W. A.; Cabanzo, R.; Mejía-Ospino, E.

    2011-01-01

    In this work, Laser Induced Breakdown Spectroscopy (LIBS) is used to determine the Si/Al ratio of Zeolite type Y. The catalytic activity of zeolite is strongly dependent of the Si/Al ratio. We have used Si lines in the spectral region between 245-265 nm to determine temperature of the plasma generated on pelletized sample of zeolite, and stoichiometry relation between Si and Al.

  20. Optimization of liquid jet system for laser-induced breakdown spectroscopy analysis.

    Science.gov (United States)

    Skočovská, Katarína; Novotný, Jan; Prochazka, David; Pořízka, Pavel; Novotný, Karel; Kaiser, Jozef

    2016-04-01

    A complex optimization of geometrical and temporal parameters of a jet system (developed in Laser-induced breakdown spectroscopy (LIBS) laboratory of Brno University of Technology) for direct elemental analysis of samples in a liquid state of matter using LIBS was carried out. First, the peristaltic pump was synchronized with the flashlamp of the ablation laser, which reduced variation of the ablated sample amount. Also, the fluctuation of the laser ray angle incident on the jet surface was diminished. Such synchronization reduced signal standard deviations and thus increased repeatability of the measurements. Then, laser energy and distance of the focusing lens from the sample were optimized. The gate delay time and the gate width were optimized for single pulse (SP) experiments; the gate delay time and the inter-pulse delay were optimized for the use of double pulse (DP) variant. Results were assessed according to the highest signal to noise ratios and the lowest relative standard deviations of the signal. The sensitivity of the single pulse and the double pulse LIBS for the detection of heavy metals traces, copper (Cu i at 324.754 nm) and lead (Pb i at 405.781 nm), in aqueous solution of copper (ii) sulfate and lead (ii) acetate, was estimated in terms of limits of detection (LODs). As a result, sensitivity improvement of DP LIBS system was observed, the LOD of Cu obtained with DP was calculated 40% lower than LOD gained from SP technique.

  1. Optimization of liquid jet system for laser-induced breakdown spectroscopy analysis

    Science.gov (United States)

    Skočovská, Katarína; Novotný, Jan; Prochazka, David; Pořízka, Pavel; Novotný, Karel; Kaiser, Jozef

    2016-04-01

    A complex optimization of geometrical and temporal parameters of a jet system (developed in Laser-induced breakdown spectroscopy (LIBS) laboratory of Brno University of Technology) for direct elemental analysis of samples in a liquid state of matter using LIBS was carried out. First, the peristaltic pump was synchronized with the flashlamp of the ablation laser, which reduced variation of the ablated sample amount. Also, the fluctuation of the laser ray angle incident on the jet surface was diminished. Such synchronization reduced signal standard deviations and thus increased repeatability of the measurements. Then, laser energy and distance of the focusing lens from the sample were optimized. The gate delay time and the gate width were optimized for single pulse (SP) experiments; the gate delay time and the inter-pulse delay were optimized for the use of double pulse (DP) variant. Results were assessed according to the highest signal to noise ratios and the lowest relative standard deviations of the signal. The sensitivity of the single pulse and the double pulse LIBS for the detection of heavy metals traces, copper (Cu i at 324.754 nm) and lead (Pb i at 405.781 nm), in aqueous solution of copper (ii) sulfate and lead (ii) acetate, was estimated in terms of limits of detection (LODs). As a result, sensitivity improvement of DP LIBS system was observed, the LOD of Cu obtained with DP was calculated 40% lower than LOD gained from SP technique.

  2. Geographical analysis of ``conflict minerals'' utilizing laser-induced breakdown spectroscopy

    Science.gov (United States)

    Hark, Richard R.; Remus, Jeremiah J.; East, Lucille J.; Harmon, Russell S.; Wise, Michael A.; Tansi, Benjamin M.; Shughrue, Katrina M.; Dunsin, Kehinde S.; Liu, Chunyi

    2012-08-01

    Laser-induced breakdown spectroscopy (LIBS) offers a means of rapidly distinguishing different geographic sources for a mineral because the LIBS plasma emission spectrum provides information on the chemical composition (i.e. geochemical fingerprint) of a geomaterial. An application of this approach with potentially significant commercial and political importance is the spectral fingerprinting of "conflict minerals" such as columbite-tantalite ("coltan"). Following a successful pilot study of a columbite-tantalite suite from North America, a more geographically diverse set of 57 samples from 37 locations around the world was analyzed using a commercially available LIBS system. The LIBS spectra were analyzed using advanced multivariate statistical signal processing techniques. Partial least squares discriminant analysis (PLSDA) resulted in a correct place-level geographic classification at success rates above 90%. The possible role of rare-earth elements (REEs) as a factor contributing to the high levels of sample discrimination was explored. These results provide additional evidence that LIBS has the potential to be utilized in the field as a real-time screening tool to discriminate between columbite-tantalite ores of different provenance.

  3. Development of a Laboratory Cement Quality Analysis Apparatus Based on Laser-Induced Breakdown Spectroscopy

    Science.gov (United States)

    Fan, Juanjuan; Zhang, Lei; Wang, Xin; Li, Yufang; Gong, Yao; Dong, Lei; Ma, Weiguang; Yin, Wangbao; Wang, Zhe; Li, Zheng; Zhang, Xiangjie; Li, Yi; Jia, Suotang

    2015-11-01

    Determination of the chemical composition of cement and ratio values of clinker plays an important role in cement plants as part of the optimal process control and product quality evaluation. In the present paper, a laboratory laser-induced breakdown spectroscopy (LIBS) apparatus mainly comprising a sealed optical module and an analysis chamber has been designed for possible application in cement plants for on-site quality analysis of cement. Emphasis is placed on the structure and operation of the LIBS apparatus, the sealed optical path, the temperature controlled spectrometer, the sample holder, the proper calibration model established for minimizing the matrix effects, and a correction method proposed for overcoming the ‘drift’ obstacle. Good agreement has been found between the laboratory measurement results from the LIBS method and those from the traditional method. The absolute measurement errors presented here for oxides analysis are within 0.5%, while those of ratio values are in the range of 0.02 to 0.05. According to the obtained results, this laboratory LIBS apparatus is capable of performing reliable and accurate, composition and proximate analysis of cement and is suitable for application in cement plants. supported by National Natural Science Foundation of China (Nos. 61127017, 61378047, 61205216, 61178009, 61108030, 61475093, and 61275213), the National Key Technology R&D Program of China (No. 2013BAC14B01), the 973 Program of China (No. 2012CB921603), the Shanxi Natural Science Foundation, China (Nos. 2013021004-1, 2012021022-1), and the Shanxi Scholarship Council of China (Nos. 2013-011 and 2013-01)

  4. Rapid Analysis of Energetic and Geo-Materials Using Laser Induced Breakdown Spectroscopy

    Science.gov (United States)

    2013-04-01

    Anal (2005) 5, 21. 20. Anzano, J. M., et al., Anal Chim Acta (2006) 575, 230. 21. Rusak, D. A., et al., TrAC Trend Anal Chem (1998) 17, 453. 22. Martin ...Spectrosc Reviews (2004) 39, 27. 25. Winefordner, J. D., et al., J Anal Atom Spectrom (2004) 19, 1061. 26. Cremers , D. A., and Radziemski, L. J., Handbook...29. Singh, J. P. and Thakur, S. N., Eds., Laser-Induced Breakdown Spectroscopy, Elsevier: Amsterdam, The Netherlands, 2007. 30. Cremers , D. A., and

  5. Quantitative Analysis of Carbon Steel with Multi-Line Internal Standard Calibration Method Using Laser-Induced Breakdown Spectroscopy.

    Science.gov (United States)

    Pan, Congyuan; Du, Xuewei; An, Ning; Zeng, Qiang; Wang, Shengbo; Wang, Qiuping

    2016-04-01

    A multi-line internal standard calibration method is proposed for the quantitative analysis of carbon steel using laser-induced breakdown spectroscopy (LIBS). A procedure based on the method was adopted to select the best calibration curves and the corresponding emission lines pairs automatically. Laser-induced breakdown spectroscopy experiments with carbon steel samples were performed, and C, Cr, and Mn were analyzed via the proposed method. Calibration curves of these elements were constructed via a traditional single line internal standard calibration method and a multi-line internal standard calibration method. The calibration curves obtained were evaluated with the determination coefficient, the root mean square error of cross-validation, and the average relative error of cross-validation. All of the parameters were improved significantly with the proposed method. The results show that accurate and stable calibration curves can be obtained efficiently via the multi-line internal standard calibration method.

  6. Laser induced breakdown spectroscopy on meteorites

    Energy Technology Data Exchange (ETDEWEB)

    De Giacomo, A. [Department of Chemistry, University of Bari (Italy); MIP-CNR sec Bari (Italy)], E-mail: alessandro.degiacomo@ba.imip.cnr.it; Dell' Aglio, M.; De Pascale, O. [MIP-CNR sec Bari (Italy); Longo, S.; Capitelli, M. [Department of Chemistry, University of Bari (Italy); MIP-CNR sec Bari (Italy)

    2007-12-15

    The classification of meteorites when geological analysis is unfeasible is generally made by the spectral line emission ratio of some characteristic elements. Indeed when a meteorite impacts Earth's atmosphere, hot plasma is generated, as a consequence of the braking effect of air, with the consequent ablation of the falling body. Usually, by the plasma emission spectrum, the meteorite composition is determined, assuming the Boltzmann equilibrium. The plasma generated during Laser Induced Breakdown Spectroscopy (LIBS) experiment shows similar characteristics and allows one to verify the mentioned method with higher accuracy. On the other hand the study of Laser Induced Breakdown Spectroscopy on meteorite can be useful for both improving meteorite classification methods and developing on-flight techniques for asteroid investigation. In this paper certified meteorites belonging to different typologies have been investigated by LIBS: Dofhar 461 (lunar meteorite), Chondrite L6 (stony meteorite), Dofhar 019 (Mars meteorite) and Sikhote Alin (irony meteorite)

  7. Elemental analysis of powders with surface-assisted thin film laser-induced breakdown spectroscopy

    Science.gov (United States)

    Tian, Ye; Cheung, Hoi Ching; Zheng, Ronger; Ma, Qianli; Chen, Yanping; Delepine-Gilon, Nicole; Yu, Jin

    2016-10-01

    We have developed in this work a method of elemental analysis of powdered materials with laser-induced breakdown spectroscopy (LIBS). This method requires simple sample preparation. Powders are first mixed into a 75 cSt base oil to obtain a paste which is then smeared onto the polished surface of a solid state substrate, aluminum plate for instance, in the form of a uniform thin film. The prepared sample is ablated by a high energy infrared (IR at 1064 nm) nanosecond laser pulse. The laser beam transmits through the coating layer of the material to be analyzed and induces a strong plasma from the substrate. The initial plasma interacts in turn with the coating layer, leading to the vaporization and excitation of the incorporated powder particles. The subsequent emission from the plasma includes emission lines of the elements contained in the powder, which is preferentially captured by a suitable detection system. The analysis of the recorded spectrum allows the concentration determination of the targeted elements in the powder. We first applied the method on a cellulose powder of 20 μm typical particle size. The powder was spiked with titanium dioxide (TiO2) nanoparticles for Ti concentrations ranging from 25 ppm to 5000 ppm by weight. Calibration graphs were thus built to deduce figures-of-merit parameters such as the coefficient of determination (R2) and the limits of detection and quantification (LoD and LoQ). We optimized especially the choice of reference line for spectrum normalization, which resulted in better analytical performances. In the second step, two sets of powders, the aforementioned cellulose powder and an alumina powder with average particle size of ≤ 10 μm, were spiked with TiO2 nanoparticles. We then assessed the matrix effect between these two different powders for the determination of Ti by comparing their calibration curves. Our results show universal calibration curve in Ti determination in the two tested matrices. The results are

  8. Application of laser-induced breakdown spectroscopy to the analysis of algal biomass for industrial biotechnology

    Science.gov (United States)

    Pořízka, P.; Prochazka, D.; Pilát, Z.; Krajcarová, L.; Kaiser, J.; Malina, R.; Novotný, J.; Zemánek, P.; Ježek, J.; Šerý, M.; Bernatová, S.; Krzyžánek, V.; Dobranská, K.; Novotný, K.; Trtílek, M.; Samek, O.

    2012-08-01

    We report on the application of laser-induced breakdown spectroscopy (LIBS) to the determination of elements distinctive in terms of their biological significance (such as potassium, magnesium, calcium, and sodium) and to the monitoring of accumulation of potentially toxic heavy metal ions in living microorganisms (algae), in order to trace e.g. the influence of environmental exposure and other cultivation and biological factors having an impact on them. Algae cells were suspended in liquid media or presented in a form of adherent cell mass on a surface (biofilm) and, consequently, characterized using their spectra. In our feasibility study we used three different experimental arrangements employing double-pulse LIBS technique in order to improve on analytical selectivity and sensitivity for potential industrial biotechnology applications, e.g. for monitoring of mass production of commercial biofuels, utilization in the food industry and control of the removal of heavy metal ions from industrial waste waters.

  9. X-Ray Fluorescence and Laser-Induced Breakdown Spectroscopy analysis of Roman silver denarii

    Energy Technology Data Exchange (ETDEWEB)

    Pardini, L. [Istituto di Chimica dei Composti Organometallici del CNR, Research Area of Pisa, Via G. Moruzzi 1, 56124 Pisa (Italy); El Hassan, A. [National Institute for Laser- Enhanced Sciences (NILES), Cairo University Giza (Egypt); Ferretti, M. [Istituto per le Tecnologie Applicate ai Beni Culturali, Area della Ricerca del CNR di Montelibretti Roma (Italy); Foresta, A.; Legnaioli, S.; Lorenzetti, G. [Istituto di Chimica dei Composti Organometallici del CNR, Research Area of Pisa, Via G. Moruzzi 1, 56124 Pisa (Italy); Nebbia, E. [Universita degli Studi di Torino (Italy); Catalli, F. [Monetiere di Firenze, Museo Archeologico Nazionale Firenze (Italy); Harith, M.A. [National Institute for Laser- Enhanced Sciences (NILES), Cairo University Giza (Egypt); Diaz Pace, D. [Institute of Physics ' Arroyo Seco' , Faculty of Science, Tandil (Argentina); Anabitarte Garcia, F. [Photonics Engineering Group, University of Cantabria, Santander (Spain); Scuotto, M. [Dipartimento di Scienze Archeologiche, Via Galvani 1, 56126 Pisa (Italy); Palleschi, V., E-mail: vincenzo.palleschi@cnr.it [Istituto di Chimica dei Composti Organometallici del CNR, Research Area of Pisa, Via G. Moruzzi 1, 56124 Pisa (Italy); Dipartimento di Scienze Archeologiche, Via Galvani 1, 56126 Pisa (Italy)

    2012-08-15

    In this paper we present the results of a study performed on a large collection of silver Roman republican denarii, encompassing about two centuries of history. The joint use of Laser-Induced Breakdown Spectroscopy (LIBS) and X-Ray Fluorescence (XRF) spectroscopy allowed for an accurate determination of the coins' elemental composition; the measurements, performed mostly in situ at the 'Monetiere' in Florence, revealed a striking connection between the 'quality' of the silver alloy and some crucial contemporary events. This finding was used to classify a group of denarii whose dating was otherwise impossible. The comparison with other contemporary denarii disproves a recent theory on the origin of the so called 'serrated' denarii (denarii showing notched chisel marks on the edge of the coin). - Highlights: Black-Right-Pointing-Pointer We studied a large collection of Roman republican silver denarii. Black-Right-Pointing-Pointer XRF and LIBS allowed to determine the precious metal content of the coins. Black-Right-Pointing-Pointer A correlation of the 'quality' of the alloy with some contemporary events was found. Black-Right-Pointing-Pointer The study allowed to controvert a recent theory on the so called 'serrated' denarii.

  10. Fast analysis of complex metallic alloys by double-pulse time-integrated Laser-Induced Breakdown Spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Sorrentino, F., E-mail: marwan@df.unipi.i [Marwan Technology s.r.l., Spin-off University of Pisa Largo Pontecorvo 3, 56127 Pisa (Italy); Carelli, G.; Francesconi, F.; Francesconi, M.; Marsili, P. [Marwan Technology s.r.l., Spin-off University of Pisa Largo Pontecorvo 3, 56127 Pisa (Italy); Cristoforetti, G.; Legnaioli, S.; Palleschi, V.; Tognoni, E. [Applied Laser Spectroscopy Laboratory, IPCF/CNR - Via G.Moruzzi 1, 56124 Pisa (Italy)

    2009-10-15

    Results are reported on the application of double-pulse Laser-Induced Breakdown Spectroscopy (LIBS) for fast analysis of complex metallic alloys. The approach followed for the determination of the composition of the alloys is based on the time-integrated acquisition of LIBS spectra emitted by plasmas induced by collinear double-pulse laser excitation. The spectra are analysed using the Partial Least Squares method, which allows the determination of sample composition even in the presence of strong spectral interferences. The results shown indicate the possibility of measuring the composition of complex metallic alloys in very short times and using relatively cheap LIBS instrumentation.

  11. Development of a Stand-off Laser Induced Breakdown Spectroscopy (ST-LIBS) system for the analysis of complex matrices

    Science.gov (United States)

    Tamboli, M. M.; Unnikrishnan, V. K.; Nayak, R.; Devangad, P.; Muhammed Shameem, K. M.; Kartha, V. B.; Santhosh, C.

    2016-08-01

    In the present work, we discuss the evaluation and optimization of a stand-off laser induced breakdown spectroscopy (ST-LIBS) system, developed indigenously for remote analysis of heavy elements in soil. A compact Q-switched Nd:YAG laser operating at fundamental wavelength 1064 nm was used for plasma generation at distances up to 6 meters. Techniques for optimal experimental results were evaluated for detection of Cd, Cr, Pb, Mo and Ni in soil. The system was evaluated with two NIST certified soil samples. The effect of working distance on the LIBS signal is also discussed briefly. Results confirm the capabilities of the system for remote monitoring.

  12. Spectrochemical Analysis of Soil around Leather Tanning Industry Using Laser Induced Breakdown Spectroscopy

    Directory of Open Access Journals (Sweden)

    Shakeel Ahmad Khan

    2013-01-01

    Full Text Available We report the use of laser induced breakdown spectroscopy (LIBS to determine the chromium contamination of soil due to effluents from leather tanning industry in Kasur District of Punjab (+31∘6′23.21″, +74∘27′16.29″ in Pakistan. Calibration curves were constructed by indigenously prepared standard sample and fitting of curves by linear regression. The limit of detection (LOD was found to be 23.71 mg kg−1. It has been found that the concentration of chromium in the soil is up to 839 mg kg−1 in vicinity of effluent drain and 1829 mg kg−1 in the area of old stagnant pool, which is much higher than the safe limits. Qualitative detection of other elements like Na, Cl, Fe, P, and Si was done from LIBS spectra. The leaching of soil contaminants due to seepage of industrial effluents from deteriorating brick lined drains in horizontal direction has also been observed.

  13. Quantitative analysis of arsenic in mine tailing soils using double pulse-laser induced breakdown spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Kwak, Ji-hyun [Department of Environmental Science and Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju 500-712 (Korea, Republic of); Lenth, Christoph; Salb, Christian [Photonic Sensor Technology, Laser-Laboratorium Goettingen e.V., Hans-Adolf-Krebs-Weg 1 D-37077 Goettingen (Germany); Ko, Eun-Joung; Kim, Kyoung-Woong [Department of Environmental Science and Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju 500-712 (Korea, Republic of); Park, Kihong, E-mail: kpark@gist.ac.k [Department of Environmental Science and Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju 500-712 (Korea, Republic of)

    2009-10-15

    A double pulse-laser induced breakdown spectroscopy (DP-LIBS) was used to determine arsenic (As) concentration in 16 soil samples collected from 5 different mine tailing sites in Korea. We showed that the use of double pulse laser led to enhancements of signal intensity (by 13% on average) and signal-to-noise ratio of As emission lines (by 165% on average) with smaller relative standard deviation compared to single pulse laser approach. We believe this occurred because the second laser pulse in the rarefied atmosphere produced by the first pulse led to the increase of plasma temperature and populations of exited levels. An internal standardization method using a Fe emission line provided a better correlation and sensitivity between As concentration and the DP-LIBS signal than any other elements used. The Fe was known as one of the major components in current soil samples, and its concentration varied not substantially. The As concentration determined by the DP-LIBS was compared with that obtained by atomic absorption spectrometry (AAS) to evaluate the current LIBS system. They are correlated with a correlation coefficient of 0.94. The As concentration by the DP-LIBS was underestimated in the high concentration range (>1000 mg-As/kg). The loss of sensitivity that occurred at high concentrations could be explained by self-absorption in the generated plasma.

  14. Rapid Analysis of Ash Composition Using Laser-Induced Breakdown Spectroscopy (LIBS)

    Energy Technology Data Exchange (ETDEWEB)

    Tyler L. Westover

    2013-01-01

    Inorganic compounds are known to be problematic in the thermochemical conversion of biomass to syngas and ultimately hydrocarbon fuels. The elements Si, K, Ca, Na, S, P, Cl, Mg, Fe, and Al are particularly problematic and are known to influence reaction pathways, contribute to fouling and corrosion, poison catalysts, and impact waste streams. Substantial quantities of inorganic species can be entrained in the bark of trees during harvest operations. Herbaceous feedstocks often have even greater quantities of inorganic constituents, which can account for as much as one-fifth of the total dry matter. Current methodologies to measure the concentrations of these elements, such as inductively coupled plasma-optical emission spectrometry/mass spectrometry (ICP-OES/MS) are expensive in time and reagents. This study demonstrates that a new methodology employing laser-induced breakdown spectroscopy (LIBS) can rapidly and accurately analyze the inorganic constituents in a wide range of biomass materials, including both woody and herbaceous examples. This technique requires little or no sample preparation, does not consume any reagents, and the analytical data is available immediately. In addition to comparing LIBS data with the results from ICP-OES methods, this work also includes discussions of sample preparation techniques, calibration curves for interpreting LIBS spectra, minimum detection limits, and the use of internal standards and standard reference materials.

  15. Analysis of metal surfaces coated with europium-doped titanium dioxide by laser induced breakdown spectroscopy.

    Science.gov (United States)

    Głogocka, Daria; Noculak, Agnieszka; Pucińska, Joanna; Jopek, Wojciech; Podbielska, Halina; Langner, Marek; Przybyło, Magdalena

    2015-01-01

    The surface passivation with titanium sol-gel coatings is a frequently used technique to control the adsorption of selected biological macromolecules and to reduce the exposure of the bulk material to biological matter. Due to the increasing number of new coating-preparation methods and new gel compositions with various types of additives, the quality and homogeneity determination of the surface covering is a critical factor affecting performance of any implanted material. While coating thickness is easy to determine, the homogeneity of the surface distribution of coating materials requires more elaborate methodologies. In the paper, the laser induced breakdown spectroscopy (LIBS) based method, capable to quantitate the homogeneity and uniformity of the europium in titanium dioxide sol-gel coatings on stainless steel surfaces prepared with two different procedures: spin-coating and dip-coating, is presented. The emission intensity of titanium has been used to determine the coating thickness whereas the relative values of europium and titanium emission intensities provide data on the coating homogeneity. The obtained results show that the spin-coating technique provides better surface coverage with titanium dioxide. However, when the surface coating compositions were compared the dip-coating technique was more reliable.

  16. Laser Induced Breakdown Spectroscopy for Elemental Analysis in Environmental, Cultural Heritage and Space Applications: A Review of Methods and Results

    Directory of Open Access Journals (Sweden)

    Alessandro De Giacomo

    2010-08-01

    Full Text Available Analytical applications of Laser Induced Breakdown Spectroscopy (LIBS, namely optical emission spectroscopy of laser-induced plasmas, have been constantly growing thanks to its intrinsic conceptual simplicity and versatility. Qualitative and quantitative analysis can be performed by LIBS both by drawing calibration lines and by using calibration-free methods and some of its features, so as fast multi-elemental response, micro-destructiveness, instrumentation portability, have rendered it particularly suitable for analytical applications in the field of environmental science, space exploration and cultural heritage. This review reports and discusses LIBS achievements in these areas and results obtained for soils and aqueous samples, meteorites and terrestrial samples simulating extraterrestrial planets, and cultural heritage samples, including buildings and objects of various kinds.

  17. Laser induced breakdown spectroscopy for elemental analysis in environmental, cultural heritage and space applications: a review of methods and results.

    Science.gov (United States)

    Gaudiuso, Rosalba; Dell'Aglio, Marcella; De Pascale, Olga; Senesi, Giorgio S; De Giacomo, Alessandro

    2010-01-01

    Analytical applications of Laser Induced Breakdown Spectroscopy (LIBS), namely optical emission spectroscopy of laser-induced plasmas, have been constantly growing thanks to its intrinsic conceptual simplicity and versatility. Qualitative and quantitative analysis can be performed by LIBS both by drawing calibration lines and by using calibration-free methods and some of its features, so as fast multi-elemental response, micro-destructiveness, instrumentation portability, have rendered it particularly suitable for analytical applications in the field of environmental science, space exploration and cultural heritage. This review reports and discusses LIBS achievements in these areas and results obtained for soils and aqueous samples, meteorites and terrestrial samples simulating extraterrestrial planets, and cultural heritage samples, including buildings and objects of various kinds.

  18. Discrimination of healthy and carious teeth using laser-induced breakdown spectroscopy and partial least square discriminant analysis.

    Science.gov (United States)

    Gazmeh, Meisam; Bahreini, Maryam; Tavassoli, Seyed Hassan

    2015-01-01

    In the laser drilling of teeth, a microplasma is generated which may be utilized for elemental analysis of ablated tissue via a laser-induced breakdown spectroscopy (LIBS) technique. In this study, LIBS is used to investigate the possibility of discrimination of healthy and carious tooth tissues. This possibility is examined using multivariate statistical analysis called partial least square discriminant analysis (PLS-DA) based on atomic and ionic emission lines of teeth LIBS spectra belonging to P, Ca, Mg, Zn, K, Sr, C, Na, H, and O elements. Results show an excellent discrimination and prediction of unknown tooth tissues. It is shown that using the PLS-DA method, the spectroscopic analysis of plasma emission during the laser drilling, would be a promising technique for caries detection.

  19. Atomization efficiency and photon yield in laser-induced breakdown spectroscopy analysis of single nanoparticles in an optical trap

    Science.gov (United States)

    Purohit, Pablo; Fortes, Francisco J.; Laserna, J. Javier

    2017-04-01

    Laser-induced breakdown spectroscopy (LIBS) was employed for investigating the influence of particle size on the dissociation efficiency and the absolute production of photons per mass unit of airborne solid graphite spheres under single-particle regime. Particles of average diameter of 400 nm were probed and compared with 2 μm particles. Samples were first catapulted into aerosol form and then secluded in an optical trap set by a 532 nm laser. Trap stability was quantified before subjecting particles to LIBS analysis. Fine alignment of the different lines comprising the optical catapulting-optical trapping-laser-induced breakdown spectroscopy instrument and tuning of excitation parameters conditioning the LIBS signal such as fluence and acquisition delay are described in detail with the ultimate goal of acquiring clear spectroscopic data on masses as low as 75 fg. The atomization efficiency and the photon yield increase as the particle size becomes smaller. Time-resolved plasma imaging studies were conducted to elucidate the mechanisms leading to particle disintegration and excitation.

  20. [Influence of laser power and incident angle as well as testing distance on laser inducted breakdown spectroscopy (LIBS) technology for spectroscopy diagnosis and multi-element analysis].

    Science.gov (United States)

    Zhai, Yang; Zhu, Ri-Hong; Shen, Hua; Gu, Jin-Liang

    2011-10-01

    Laser inducted breakdown spectroscopy (LIBS) technology has been used widely for the multi-element analysis of different samples and also an effective way to realize the spectroscopy diagnosis applied to calculating the electron temperature and vibration-rotation temperature etc of some certain elements. It is a highly effective measurement for its non-contact and nondestructive on-line analysis with the help of a high-speed response CCD camera. In the present paper, the authors tested an alley though LIBS technology to determine its elements in terms of species and quantities and also discussed some influences of the incident angle and the power changes of the laser beam as well as the measurement distance changes on the experimental results and and gave appropriate theoretical explanation.

  1. The application of spectrum standardization method for carbon analysis in coal using laser-induced breakdown spectroscopy

    CERN Document Server

    Li, Xiongwei; Fu, Yangting; Li, Zheng; Liu, Jianming; Ni, Weidou

    2014-01-01

    Measurements of carbon content in coal using laser-induced breakdown spectroscopy (LIBS) is limited by its low measurement precision and accuracy. A spectrum standardization method was proposed to achieve both reproducible and accurate results for the quantitative analysis of carbon content in coal with LIBS. The proposed method utilized the molecular carbon emissions to compensate the diminution of atomic carbon emission caused by matrix effect. The compensated carbon line intensities were further converted into an assumed standard state with fixed plasma temperature, electron density, and total number density of elemental carbon, which is proportional to its concentration in the coal samples. In addition, in order to obtained better compensation for total carbon number density fluctuations, an iterative algorithm was applied, which is different from our previous standardization calculations. The modified spectrum standardization model was applied to the measurement of carbon content in 24 bituminous coal sa...

  2. Assessment of statistical uncertainty in the quantitative analysis of solid samples in motion using laser-induced breakdown spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Cabalin, L.M.; Gonzalez, A. [Department of Analytical Chemistry, University of Malaga, E-29071 Malaga (Spain); Ruiz, J. [Department of Applied Physics I, University of Malaga, E-29071 Malaga (Spain); Laserna, J.J., E-mail: laserna@uma.e [Department of Analytical Chemistry, University of Malaga, E-29071 Malaga (Spain)

    2010-08-15

    Statistical uncertainty in the quantitative analysis of solid samples in motion by laser-induced breakdown spectroscopy (LIBS) has been assessed. For this purpose, a LIBS demonstrator was designed and constructed in our laboratory. The LIBS system consisted of a laboratory-scale conveyor belt, a compact optical module and a Nd:YAG laser operating at 532 nm. The speed of the conveyor belt was variable and could be adjusted up to a maximum speed of 2 m s{sup -1}. Statistical uncertainty in the analytical measurements was estimated in terms of precision (reproducibility and repeatability) and accuracy. The results obtained by LIBS on shredded scrap samples under real conditions have demonstrated that the analytical precision and accuracy of LIBS is dependent on the sample geometry, position on the conveyor belt and surface cleanliness. Flat, relatively clean scrap samples exhibited acceptable reproducibility and repeatability; by contrast, samples with an irregular shape or a dirty surface exhibited a poor relative standard deviation.

  3. Calibration-free quantitative analysis of elemental ratios in intermetallic nanoalloys and nanocomposites using Laser Induced Breakdown Spectroscopy (LIBS).

    Science.gov (United States)

    Davari, Seyyed Ali; Hu, Sheng; Mukherjee, Dibyendu

    2017-03-01

    Intermetallic nanoalloys (NAs) and nanocomposites (NCs) have increasingly gained prominence as efficient catalytic materials in electrochemical energy conversion and storage systems. But their morphology and chemical compositions play critical role in tuning their catalytic activities, and precious metal contents. While advanced microscopy techniques facilitate morphological characterizations, traditional chemical characterizations are either qualitative or extremely involved. In this study, we apply Laser Induced Breakdown Spectroscopy (LIBS) for quantitative compositional analysis of NAs and NCs synthesized with varied elemental ratios by our in-house built pulsed laser ablation technique. Specifically, elemental ratios of binary PtNi, PdCo (NAs) and PtCo (NCs) of different compositions are determined from LIBS measurements employing an internal calibration scheme using the bulk matrix species as internal standards. Morphology and qualitative elemental compositions of the aforesaid NAs and NCs are confirmed from Transmission Electron Microscopy (TEM) images and Energy Dispersive X-ray Spectroscopy (EDX) measurements. LIBS experiments are carried out in ambient conditions with the NA and NC samples drop cast on silicon wafers after centrifugation to increase their concentrations. The technique does not call for cumbersome sample preparations including acid digestions and external calibration standards commonly required in Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES) techniques. Yet the quantitative LIBS results are in good agreement with the results from ICP-OES measurements. Our results indicate the feasibility of using LIBS in future for rapid and in-situ quantitative chemical characterizations of wide classes of synthesized NAs and NCs.

  4. Fast and sensitive trace metal analysis in aqueous solutions by laser-induced breakdown spectroscopy using wood slice substrates

    Energy Technology Data Exchange (ETDEWEB)

    Chen Zhijiang; Li Hongkun; Liu Ming [School of Physics, South China University of Technology, Guangzhou 510641 (China); Li Runhua [School of Physics, South China University of Technology, Guangzhou 510641 (China)], E-mail: rhli@scut.edu.cn

    2008-01-15

    To perform fast and sensitive trace metal analysis in aqueous solutions by laser-induced breakdown spectroscopy (LIBS) based on only one single-pulse laser system, a wood slice has been used as a liquid absorber to transform liquid sample analysis to solid sample analysis using LIBS. High detection sensitivity and good reproducibility can be achieved with this approach. Calibration curves for five metal elements, Cr, Mn, Cu, Cd, and Pb under trace concentrations, have been obtained, and the limits of their detection were determined to be in the range of 0.029-0.59 mg L{sup -1}, 2-3 orders better than those obtained by directly analyzing liquid samples where the laser was focused on a liquid surface. The wood slice was very easy to handle and thus, the whole analysis process took only 4-5 min for each sample. This approach provides a more practical approach for fast and sensitive metal element analysis in aqueous solutions using LIBS, which is especially useful for monitoring toxic heavy metals in water.

  5. Fast and sensitive trace metal analysis in aqueous solutions by laser-induced breakdown spectroscopy using wood slice substrates

    Science.gov (United States)

    Chen, Zhijiang; Li, Hongkun; Liu, Ming; Li, Runhua

    2008-01-01

    To perform fast and sensitive trace metal analysis in aqueous solutions by laser-induced breakdown spectroscopy (LIBS) based on only one single-pulse laser system, a wood slice has been used as a liquid absorber to transform liquid sample analysis to solid sample analysis using LIBS. High detection sensitivity and good reproducibility can be achieved with this approach. Calibration curves for five metal elements, Cr, Mn, Cu, Cd, and Pb under trace concentrations, have been obtained, and the limits of their detection were determined to be in the range of 0.029-0.59 mg L - 1 , 2-3 orders better than those obtained by directly analyzing liquid samples where the laser was focused on a liquid surface. The wood slice was very easy to handle and thus, the whole analysis process took only 4-5 min for each sample. This approach provides a more practical approach for fast and sensitive metal element analysis in aqueous solutions using LIBS, which is especially useful for monitoring toxic heavy metals in water.

  6. Analysis of natural and artificial ultramarine blue pigments using laser induced breakdown and pulsed Raman spectroscopy, statistical analysis and light microscopy

    Science.gov (United States)

    Osticioli, I.; Mendes, N. F. C.; Nevin, A.; Gil, Francisco P. S. C.; Becucci, M.; Castellucci, E.

    2009-08-01

    Pulsed laser induced breakdown spectroscopy (LIBS) and Raman spectroscopy were performed using a novel laboratory setup employing the same Nd:YAG laser emission at 532 nm for the analysis of five commercially available pigments collectively known as "ultramarine blue", a sodium silicate material of either mineral origin or an artificially produced glass. LIBS and Raman spectroscopy have provided information regarding the elemental and molecular composition of the samples; additionally, an analytical protocol for the differentiation between natural (lapis lazuli) and artificial ultramarine blue pigments is proposed. In particular LIBS analysis has allowed the discrimination between pigments on the basis of peaks ascribed to calcium. The presence of calcite in the natural blue pigments has been confirmed following Raman spectroscopy in specific areas of the samples, and micro-Raman and optical microscopy have further corroborated the presence of calcite inclusions in the samples of natural origin. Finally multivariate analysis of Laser induced breakdown spectra using principal component analysis (PCA) further enhanced the differentiation between natural and artificial ultramarine blue pigments.

  7. Nanometer-film analysis by the laser-induced breakdown spectroscopy method: the effects of laser focus to sample distance.

    Science.gov (United States)

    Sun, Yuxiang; Zhong, Shilei; Shan, Fukai; Lu, Yuan; Sun, Xin; Liu, Zhe; Sheng, Pengpeng

    2015-05-20

    In order to develop a method to analyze metal elements in thin-film samples rapidly, directly and without sample preparation, and to understand the mechanism of laser-film interaction and plasma formation and evolution, a laboratory laser-induced breakdown spectroscopy system was established recently for nanometer-film analysis. ZrO(2) films prepared on silicon chips by a sol-gel process were employed in the following experiment and their thickness was about 40 nm. By the initial investigation that we carried out, the stability of this system was verified and the relative standard deviation of the target peak was found to be lower than 1.6% with the help of a position system. The influences of different experimental parameters, such as laser energy, laser focus to sample distance (LFTSD) settings, and gate delay, were studied under conditions of room temperature and atmospheric pressure. The experimental results show that the LFTSD was one of the most important parameters for plasma formation and spectral collection in comparison with other parameters by means of plasma spectra and images. So the effects of the LFTSD on the spectra, plasma evolution, and craters are specially discussed in this paper. At last, we calculated the plasma temperature and electron density under optimal parameters for quantitative analysis. The result shows that the established system is available for qualitative and quantitative analysis of films under conditions of single pulse and low ablation energy.

  8. Analysis of waste electrical and electronic equipment (WEEE) using laser induced breakdown spectroscopy (LIBS) and multivariate analysis.

    Science.gov (United States)

    Ángel Aguirre, Miguel; Hidalgo, Montserrat; Canals, Antonio; Nóbrega, Joaquim A; Pereira-Filho, Edenir R

    2013-12-15

    This study shows the application of laser induced breakdown spectroscopy (LIBS) for waste electrical and electronic equipment (WEEE) investigation. Several emission spectra were obtained for 7 different mobiles from 4 different manufacturers. Using the emission spectra of the black components it was possible to see some differences among the manufacturers and some emission lines from organic elements and molecules (N, O, CN and C2) led to the highest contribution for this differentiation. Some polymeric internal parts in contact with the inner pieces of the mobiles and covered with a special paint presented a strong emission signal for Cr. The white pieces presented mainly Al, Ba and Ti in their composition. Finally, this study developed a procedure for LIBS emission spectra using chemometric strategies and suitable information can be obtained for identification of manufacturer and counterfeit products. In addition, the results obtained can improve the classification for establishing recycling strategies of e-waste.

  9. Analysis of powdered tungsten carbide hard-metal precursors and cemented compact tungsten carbides using laser-induced breakdown spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Novotny, K. [Laboratory of Atomic Spectrochemistry, Department of Chemistry, Faculty of Science, Masaryk University, Kotlarska 2, 611 37 Brno (Czech Republic)], E-mail: codl@sci.muni.cz; Stankova, A. [Laboratory of Atomic Spectrochemistry, Department of Chemistry, Faculty of Science, Masaryk University, Kotlarska 2, 611 37 Brno (Czech Republic); Haekkaenen, H.; Korppi-Tommola, J. [Department of Chemistry, University of Jyvaeskylae, P.O. BOX 35, FIN-40014 (Finland); Otruba, V.; Kanicky, V. [Laboratory of Atomic Spectrochemistry, Department of Chemistry, Faculty of Science, Masaryk University, Kotlarska 2, 611 37 Brno (Czech Republic)

    2007-12-15

    Laser-induced breakdown spectroscopy (LIBS) has been applied to the direct analysis of powdered tungsten carbide hard-metal precursors and cemented tungsten carbides. The aim of this work was to examine the possibility of quantitative determination of the niobium, titanium, tantalum and cobalt. The investigated samples were in the form of pellets, pressed with and without binder (powdered silver) and in the form of cemented tungsten carbides. The pellets were prepared by pressing the powdered material in a hydraulic press. Cemented tungsten carbides were embedded in resin for easier manipulation. Several lasers and detection systems were utilized. The Nd:YAG laser working at a basic wavelength of 1064 nm and fourth-harmonic frequency of 266 nm with a gated photomultiplier or ICCD detector HORIBA JY was used for the determination of niobium which was chosen as a model element. Different types of surrounding gases (air, He, Ar) were investigated for analysis. The ICCD detector DICAM PRO with Mechelle 7500 spectrometer with ArF laser (193 nm) and KrF laser (248 nm) were employed for the determination of niobium, titanium, tantalum and cobalt in samples under air atmosphere. Good calibration curves were obtained for Nb, Ti, and Ta (coefficients of determination r{sup 2} > 0.96). Acceptable calibration curves were acquired for the determination of cobalt (coefficient of determination r{sup 2} = 0.7994) but only for the cemented samples. In the case of powdered carbide precursors, the calibration for cobalt was found to be problematic.

  10. Analysis of powdered tungsten carbide hard-metal precursors and cemented compact tungsten carbides using laser-induced breakdown spectroscopy

    Science.gov (United States)

    Novotný, K.; Staňková, A.; Häkkänen, H.; Korppi-Tommola, J.; Otruba, V.; Kanický, V.

    2007-12-01

    Laser-induced breakdown spectroscopy (LIBS) has been applied to the direct analysis of powdered tungsten carbide hard-metal precursors and cemented tungsten carbides. The aim of this work was to examine the possibility of quantitative determination of the niobium, titanium, tantalum and cobalt. The investigated samples were in the form of pellets, pressed with and without binder (powdered silver) and in the form of cemented tungsten carbides. The pellets were prepared by pressing the powdered material in a hydraulic press. Cemented tungsten carbides were embedded in resin for easier manipulation. Several lasers and detection systems were utilized. The Nd:YAG laser working at a basic wavelength of 1064 nm and fourth-harmonic frequency of 266 nm with a gated photomultiplier or ICCD detector HORIBA JY was used for the determination of niobium which was chosen as a model element. Different types of surrounding gases (air, He, Ar) were investigated for analysis. The ICCD detector DICAM PRO with Mechelle 7500 spectrometer with ArF laser (193 nm) and KrF laser (248 nm) were employed for the determination of niobium, titanium, tantalum and cobalt in samples under air atmosphere. Good calibration curves were obtained for Nb, Ti, and Ta (coefficients of determination r2 > 0.96). Acceptable calibration curves were acquired for the determination of cobalt (coefficient of determination r2 = 0.7994) but only for the cemented samples. In the case of powdered carbide precursors, the calibration for cobalt was found to be problematic.

  11. [Analysis of lead in unknown samples based on the standard addition method using laser induced breakdown spectroscopy].

    Science.gov (United States)

    Fang, Li; Zhao, Nan-jing; Meng, De-shuo; Yuan, Jing; Tang, Jie; Wang, Yin; Yu, Yang; Ma, Ming-jun; Hu, Li; Zhang, Da-hai; Xiao, Xue; Wang, Yu; Liu, Jian-guo; Liu, Wen-qing

    2015-01-01

    The standard addition method with laser induced breakdown spectroscopy was used to analyze an unknown sample taken from a lead battery factory. the matrix influence on the results was effectively avoided when the external or internal standard method was used, and the pretreatment of samples was simple and quick. The Nd ' YAG pulse laser with wavelength 1 064 nm was used as the excitation source. The echelle spectroscopy with high resolution and wide spectral range was used as the spectral separation device, and the intensified charge coupled device (ICCD) as the spectral detection device in the experiment. The characteristic line at 405. 78 nrn was chosen as the analysis line to measure Pb concentration. Fe I : 404. 58 line was chosen as the internal standard. Pre-experiment was carried out to confirm the appropriate condition. Under the laser energy of 128. 5 mJ, the delay time of 2. 5 tps, and the gate width of 3 ps, it was determined that with the addition of Pb to the sample in the range of 0 and 25 000 mg . kg-1, there wasn't self-absorption. There was a good linear relationship between the intensity of the spectral line of 405. 78 nm and the addition of Pb. The appropriate concentration of Pb added into the sample for analysis was determined by this series of samples. On this basis, four samples were prepared with three parallel samples for each sample in order to verify the repeatability and reliability of the method, i. e. 5 000, 10 000, 15 000, 20 000 mg . kg-1 Pb was added into the original sample. The results were compared with the result of ICP-MS. The twelve samples' relative errors were between -24. 6% and 17. 6%. The average result was 43 069 mg . kg-1 with the relative error -2. 44%.

  12. Laser-induced breakdown spectroscopy in Asia

    Science.gov (United States)

    Wang, Zhen-Zhen; Deguchi, Yoshihiro; Zhang, Zhen-Zhen; Wang, Zhe; Zeng, Xiao-Yan; Yan, Jun-Jie

    2016-12-01

    Laser-induced breakdown spectroscopy (LIBS) is an analytical detection technique based on atomic emission spectroscopy to measure the elemental composition. LIBS has been extensively studied and developed due to the non-contact, fast response, high sensitivity, real-time and multi-elemental detection features. The development and applications of LIBS technique in Asia are summarized and discussed in this review paper. The researchers in Asia work on different aspects of the LIBS study in fundamentals, data processing and modeling, applications and instrumentations. According to the current research status, the challenges, opportunities and further development of LIBS technique in Asia are also evaluated to promote LIBS research and its applications.

  13. Quantitative carbon analysis in coal by combining data processing and spatial confinement in laser-induced breakdown spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Li, Xiongwei [State Key Lab of Power Systems, Department of Thermal Engineering, Tsinghua-BP Clean Energy Center, Tsinghua University, Beijing (China); Guodian New Energy Technology Research Institute, Beijing (China); Yin, Hualiang [State Key Lab of Power Systems, Department of Thermal Engineering, Tsinghua-BP Clean Energy Center, Tsinghua University, Beijing (China); Wang, Zhe, E-mail: zhewang@tsinghua.edu.cn [State Key Lab of Power Systems, Department of Thermal Engineering, Tsinghua-BP Clean Energy Center, Tsinghua University, Beijing (China); Fu, Yangting; Li, Zheng; Ni, Weidou [State Key Lab of Power Systems, Department of Thermal Engineering, Tsinghua-BP Clean Energy Center, Tsinghua University, Beijing (China)

    2015-09-01

    Online measurement of carbon content of coal is important for coal-fired power plants to realize the combustion optimization of coal-fired boilers. Given that the measurement of carbon content of coal using laser-induced breakdown spectroscopy (LIBS) suffers from low measurement accuracy because of matrix effects, our previous study has proposed a combination model to improve the measurement accuracy of carbon content of coal. The spatial confinement method, which utilizes the spectral emissions of laser-induced plasmas spatially confined by cavities for quantitative analysis, has potential to improve quantitative analysis performance. In the present study, the combination model was used for coal measurement with cylindrical cavity confinement to further improve the measurement accuracy of carbon content of coal. Results showed that measurement accuracy was improved when the combination model was used with spatial confinement method. The coefficient of determination, root-mean-square error of prediction, average relative error, and average absolute error for the combination model with cylindrical cavity confinement were 0.99, 1.35%, 1.66%, and 1.08%, respectively, whereas values for the combination model without cylindrical cavity confinement were 0.99, 1.63%, 1.82%, and 1.27%, respectively. This is the first time that the average absolute error of carbon measurement for coal analysis has achieved close to 1.0% using LIBS, which is the critical requirement set for traditional chemical processing method by Chinese national standard. These results indicated that LIBS had significant application potential for coal analysis. - Highlights: • Spatial confinement method is applied for the measurement of carbon content in coal. • Previously proposed combination model is used with spatial confinement method. • The final result is firstly close to the critical reproducibility requirement of Chinese national standard.

  14. Elemental analysis by surface-enhanced Laser-Induced Breakdown Spectroscopy combined with liquid–liquid microextraction

    OpenAIRE

    Aguirre Pastor, Miguel Ángel; Legnaioli, Stefano; Almodóvar, F.; Hidalgo Núñez, Montserrat; Palleschi, Vincenzo; Canals Hernández, Antonio

    2013-01-01

    In this work, the possibility of using Laser-Induced Breakdown Spectrometry (LIBS) combined with liquid–liquid microextraction techniques is evaluated as a simple and fast method for trace elemental analysis. Two different strategies for LIBS analysis of manganese contained in microdroplets of extraction solvent (Triton X-114) are studied: (i) analysis by direct laser irradiation of microdroplets; and (ii) analysis by laser irradiation of microdroplets dried on metallic substrates (surface-en...

  15. Accurate quantitative analysis of gold alloys using multi-pulse laser induced breakdown spectroscopy and a correlation-based calibration method

    Energy Technology Data Exchange (ETDEWEB)

    Galbacs, Gabor [Department of Inorganic and Analytical Chemistry, University of Szeged, 6720 Szeged, Dom ter 7. (Hungary)], E-mail: galbx@chem.u-szeged.hu; Jedlinszki, Nikoletta; Cseh, Gabor; Galbacs, Zoltan; Turi, Laszlo [Department of Inorganic and Analytical Chemistry, University of Szeged, 6720 Szeged, Dom ter 7. (Hungary)

    2008-05-15

    Multi-pulse laser induced breakdown spectroscopy (LIBS), in combination with the generalized linear correlation calibration method (GLCM), was applied to the quantitative analysis (fineness determination) of quaternary gold alloys. Accuracy and precision on the order of a few thousandths ( per mille ) was achieved. The analytical performance is directly comparable to that of the standard cupellation method (fire assay), but provides results within minutes and is virtually non-destructive, as it consumes only a few micrograms of the sample.

  16. Influence of particle size distribution on the analysis of pellets of plant materials by laser-induced breakdown spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Gustinelli Arantes de Carvalho, Gabriel [NAPTISA Research Support Center “Technology and Innovation for a Sustainable Agriculture”, Center for Nuclear Energy in Agriculture, University of São Paulo, Av. Centenário 303, 13416-000 Piracicaba, SP (Brazil); Santos Jr, Dário [Departamento de Ciências Exatas e da Terra, Universidade Federal de São Paulo, Rua Prof. Artur Riedel, 275, 09972-270 Diadema, SP (Brazil); Silva Gomes, Marcos da; Nunes, Lidiane Cristina; Guerra, Marcelo Braga Bueno [NAPTISA Research Support Center “Technology and Innovation for a Sustainable Agriculture”, Center for Nuclear Energy in Agriculture, University of São Paulo, Av. Centenário 303, 13416-000 Piracicaba, SP (Brazil); Krug, Francisco José, E-mail: fjkrug@cena.usp.br [NAPTISA Research Support Center “Technology and Innovation for a Sustainable Agriculture”, Center for Nuclear Energy in Agriculture, University of São Paulo, Av. Centenário 303, 13416-000 Piracicaba, SP (Brazil)

    2015-03-01

    Pellets of sieved plant materials (150, 106, 75, 53 and 20 μm sieve apertures) were prepared and analyzed by laser-induced breakdown spectroscopy (LIBS), and the results for Ca, K, Mg, P, B and Mn were discussed as a function of particle size distribution. This parameter is of key importance for appropriate test sample presentation in the form of pressed pellets for quantitative analysis by LIBS. Experiments were carried out with a Q-switched Nd:YAG laser at 1064 nm, and a spectrometer with Echelle optics and an intensified charge-coupled device. Results indicated that smaller particles yielded up to 50% emission signal intensities' enhancement and attained better measurements' precision (site-to-site variation). Moreover, matrix effects were reduced by analyzing pellets prepared from < 75 μm sieved fractions (mean particle size = 32 μm; d{sub 95} = 102 μm) and by using a 50 J cm{sup −2} laser fluence (220 mJ per pulse; 750 μm laser spot size). The preparation of pellets from laboratory samples with monomodal particle size distributions, where most particles were smaller than 100 μm, was decisive for improving analyte micro-homogeneity within the test samples and for attaining lower coefficients of variation of measurements, typically lower than 10% (n = 10 sites per pellet; 20 laser pulses per site). - Highlights: • First systematic study on the effects of particle size distribution. • Most appropriate particle sizes for pellet preparation depend on laser fluence. • Data can be used for sampling strategies aiming at LIBS analysis of plant materials.

  17. Study of cluster analysis used in explosives classification with laser-induced breakdown spectroscopy

    Science.gov (United States)

    Wang, Q. Q.; He, L. A.; Zhao, Y.; Peng, Z.; Liu, L.

    2016-06-01

    Supervised learning methods (such as partial least squares regression-discriminant analysis, SIMCA, etc) are widely used in explosives recognition. The correct classification rate may be lowered if a sample or substrate is not included in the training dataset. Unsupervised learning methods (such as hierarchical clustering analysis, K-means, etc) have the potential to solve this problem. In this paper we analyzed results of using as input variables the intensities of seven lines and then five intensity ratios of the seven lines. It was demonstrated that unsupervised learning methods had the ability to achieve a better classification result.

  18. Strategies for Mars remote Laser-Induced Breakdown Spectroscopy analysis of sulfur in geological samples

    Energy Technology Data Exchange (ETDEWEB)

    Dyar, M. Darby, E-mail: mdyar@mtholyoke.edu [Department of Astronomy, Mount Holyoke College, 50 College St., South Hadley, MA 01075 (United States); Tucker, Jonathan M., E-mail: jtucker@mtholyoke.edu [Department of Astronomy, Mount Holyoke College, 50 College St., South Hadley, MA 01075 (United States); Humphries, Seth, E-mail: sethdh@lanl.gov [Los Alamos National Laboratory, P.O. Box 1663, Los Alamos, NM 87545 (United States); Clegg, Samuel M., E-mail: sclegg@lanl.gov [Los Alamos National Laboratory, P.O. Box 1663, Los Alamos, NM 87545 (United States); Wiens, Roger C., E-mail: rwiens@lanl.gov [Los Alamos National Laboratory, P.O. Box 1663, Los Alamos, NM 87545 (United States); Lane, Melissa D., E-mail: lane@psi.edu [Planetary Science Institute, 1700 E. Ft. Lowell, Suite 106, Tucson, AZ 85719 (United States)

    2011-01-15

    The key to understanding the sulfur history on Mars is to identify and determine sulfate and sulfide compositions and then to draw from them geologic clues about their environments of formation. To lay a foundation for use of remote LIBS to sulfur analysis in planetary exploration, we have undertaken a focused study of sulfur LIBS in geological samples in a simulated Mars atmosphere, with experimental parameters replicating the ChemCam LIBS instrument. A suite of twelve samples was selected, including rocks rich in minerals representative of sulfates and sulfides that might be encountered on Mars. Univariate analysis of sulfur emission lines did not provide quantitative information. Partial least squares (PLS) analysis was successful at modeling sulfur concentrations for a subset of samples with similar matrices. Sulfide minerals were identified on the basis of other siderophile or chalcophile peaks, such as those arising from Zn and Cu. Because the S lines are very weak compared to those of other elements, optimal PLS results were obtained by restricting the wavelength range to channels close to the most intense sulfur lines {approx} 540-570 nm. Principal components analysis was attempted on the dataset, but did not differentiate the samples into meaningful groups because the sulfur lines are not strong enough. However, areas of the relatively weak S, H, and O peaks may be used to correctly classify all samples. Based on these outcomes, a flowchart that outlines a possible decision tree for identification and quantification of sulfur in remote LIBS analysis was constructed. Results suggest that LIBS data acquired under Mars conditions can meet the science requirements for the ChemCam instrument.

  19. Note: A portable laser induced breakdown spectroscopy instrument for rapid sampling and analysis of silicon-containing aerosols

    Science.gov (United States)

    McLaughlin, R. P.; Mason, G. S.; Miller, A. L.; Stipe, C. B.; Kearns, J. D.; Prier, M. W.; Rarick, J. D.

    2016-05-01

    A portable instrument has been developed for measuring silicon-containing aerosols in near real-time using laser-induced breakdown spectroscopy (LIBS). The instrument uses a vacuum system to collect and deposit airborne particulate matter onto a translatable reel of filter tape. LIBS is used to analyze the deposited material, determining the amount of silicon-containing compounds present. In laboratory testing with pure silica (SiO2), the correlation between LIBS intensity for a characteristic silicon emission and the concentration of silica in a model aerosol was determined for a range of concentrations, demonstrating the instrument's plausibility for identifying hazardous levels of silicon-containing compounds.

  20. Geographical Analysis of Conflict Minerals Utilizing Laser-Induced Breakdown Spectroscopy

    Science.gov (United States)

    2012-01-01

    geographic heterogeneity. The approach of Melcher et al. [2,8] is principally based on quantitative elemental and isotope analysis to detect these...13] M.A. Wise, Geochemistry and crystal chemistry of Nb, Ta and Sn minerals from the Yellowknife pegmatite field, N.W.T. PhD thesis, Univ. Manitoba...metal pegmatite bodies of Jharkhand, Bihar, and Karnataka; a significant milestone in the growth of ore- geochemistry in India, Mem. Geol. Soc. India 73

  1. Laser-Induced Breakdown Spectroscopy to high-resolution analysis of ion distribution in cement-bound solid; Laser-induzierte Breakdown Spektroskopie (LIBS) zur hochaufloesenden Analyse der Ionenverteilung in zementgebundenen Feststoffen

    Energy Technology Data Exchange (ETDEWEB)

    Molkenthin, Andre

    2009-06-03

    The Laser-Induced Breakdown Spectroscopy allows imaging and quantitative analysis of the ion distribution of all relevant elements on the surface of mineral building materials. The measuring system has been characterised by investigations on specimens of hardened cement paste, mortar and concrete. Transport and accumulation processes are visualised. Besides, results are introduced for the peripheral zone close to the surface and the extraction is shown. (orig.) [German] Die Laser-induzierte Breakdown Spektroskopie ermoeglicht eine bildgebende und quantitative Analyse der Ionenverteilung aller massgeblichen Elemente auf mineralischen Baustoffoberflaechen. Das Messsystem wurde durch verfahrenspezifische Untersuchungen an Proben aus Zementstein, -moerteln und Betonen charakterisiert, Transport- und Anlagerungsprozesse wurden visuell dargestellt. Zudem werden Ergebnisse fuer den Ionenhaushalt in der ungestoerten oberflaechenahen Randzone sowie bei deren Auslaugung bzw. Anreicherung vorgestellt.

  2. Analysis of alumina-based titanium carbide composites by laser-induced breakdown spectroscopy

    Science.gov (United States)

    Ahmad, Kaleem; Tawfik, Walid; Farooq, Wazirzada A.; Singh, Jagdish P.

    2014-06-01

    In this work, alumina (Al2O3) containing different volume % of titanium carbide (TiC) ranging from 0 to 30 were consolidated by the novel spark plasma sintering. The spectroscopic analysis of the plasma generated by irradiation of laser Nd:YAG (λ = 1,064 nm) on different concentrations of the composites in air atmospheric pressure was performed. The qualitative examination of the composites confirms the presence of aluminum, titanium, and carbon as major elements, while magnesium and sodium have been found as minor trace elements. Plasma parameters were estimated by assuming the LTE conditions for optically thin plasma. The electron density and temperature were evaluated by using the Stark broadening and intensity of selected aluminum emission lines, respectively. The addition of TiC to Al2O3 shows a linear behavior with plasma temperature corroborated by the calibration curve of Ti in the composites. The results suggest that calibration curve between plasma temperature and the composites can be used to estimate different concentrations of TiC in Al2O3 without analyzing the whole elements in the composites and thus opens up new applications of LIBS in ceramic industry.

  3. Calibration-free inverse method for depth-profile analysis with laser-induced breakdown spectroscopy

    Science.gov (United States)

    Gaudiuso, R.

    2016-09-01

    The Calibration-free inverse method (CF-IM) is a variant of the classical CF approach that can be used for the determination of the plasma temperature using a single calibration standard. In this work, the IM was suitably modified in order to test its applicability to the depth-resolved elemental analyses of stratified samples. The single calibration standard was used as a sort of reference sample to model the acquisition conditions of the spectra, to investigate the effect of the acquisition geometry, and to account for possible crater-induced changes in the acquired spectra and plasma parameters. Thus, a depth profile of the standard sample was performed in order to obtain a plasma temperature profile, which in turn was employed, together with the experimental electron density profile, for the depth profile calibration-free analysis. The methodology was also applied to archaeological samples, with the purpose of testing the method with weathered and layered samples, and compared with the results of classical LIBS with calibration lines.

  4. Trace metal mapping by laser-induced breakdown spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Kaiser, Jozef [ORNL; Novotny, Dr. Karel [Masaryk University; Hrdlicka, A [Brno University of Technology, Czech Republic; Malina, R [Brno University of Technology, Czech Republic; Hartl, M [Brno University of Technology, Czech Republic; Kizek, R [Mendel University of Brno; Adam, V [Mendel University of Brno

    2012-01-01

    Abstract: Laser-Induced Breakdown Spectroscopy (LIBS) is a sensitive optical technique capable of fast multi-elemental analysis of solid, gaseous and liquid samples. The potential applications of lasers for spectrochemical analysis were developed shortly after its invention; however the massive development of LIBS is connected with the availability of powerful pulsed laser sources. Since the late 80s of 20th century LIBS dominated the analytical atomic spectroscopy scene and its application are developed continuously. Here we review the utilization of LIBS for trace elements mapping in different matrices. The main emphasis is on trace metal mapping in biological samples.

  5. Laser-Induced Breakdown Spectroscopy: Fundamentals, Applications, and Challenges

    OpenAIRE

    Anabitarte, F.; Cobo, A.; J. M. Lopez-Higuera

    2012-01-01

    Laser-induced breakdown spectroscopy (LIBS) is a technique that provides an accurate in situ quantitative chemical analysis and, thanks to the developments in new spectral processing algorithms in the last decade, has achieved a promising performance as a quantitative chemical analyzer at the atomic level. These possibilities along with the fact that little or no sample preparation is necessary have expanded the application fields of LIBS. In this paper, we review the state of the ar...

  6. Characteristics of the ablation plume induced on glasses for analysis purposes with laser-induced breakdown spectroscopy

    Science.gov (United States)

    Tian, Ye; Sokolova, Ekaterina B.; Zheng, Ronger; Ma, Qianli; Chen, Yanping; Yu, Jin

    2015-12-01

    Laser-induced breakdown spectroscopy (LIBS) has been demonstrated as an efficient tool for elemental analyses of transparent dielectric materials such as glasses or crystals for more than ten years. The induced plasma is however much less studied compared to that induced on the surface of a metal. The purpose of this work is therefore to characterize the plasma induced on the surface of a glass sample for analytical purpose as a function of the ablation laser wavelength, infrared (IR) or ultraviolet (UV), and the ambient gas, air or argon. The surface damage of the samples was also observed for ablation with IR or UV laser pulse when the sample was a float glass or a frosted one. Optimized ablation fluence was then determined. The morphology of the plasma was observed with time-resolved spectroscopic imaging, while the profiles of the electron density and temperature were extracted from time- and space-resolved emission spectroscopy. The analytical performance of the plasmas was then studied in terms of the signal-to-noise ratio for several emission lines from some minor elements, Al, Fe, contained in glasses, and of the behavior of self-absorption for another minor element, Ca, in the different ablation conditions.

  7. Elemental analysis by surface-enhanced Laser-Induced Breakdown Spectroscopy combined with liquid–liquid microextraction

    Energy Technology Data Exchange (ETDEWEB)

    Aguirre, M.A. [Department of Analytical Chemistry and Food Science and University Institute of Materials, Faculty of Science, University of Alicante, Alicante E-03080 (Spain); Legnaioli, S. [Applied Laser Spectroscopy Laboratory, Institute of Chemistry of Organometallic Compounds, National Research Council (CNR), Pisa I-56124 (Italy); Almodóvar, F. [Department of Analytical Chemistry and Food Science and University Institute of Materials, Faculty of Science, University of Alicante, Alicante E-03080 (Spain); Hidalgo, M., E-mail: montserrat.hidalgo@ua.es [Department of Analytical Chemistry and Food Science and University Institute of Materials, Faculty of Science, University of Alicante, Alicante E-03080 (Spain); Palleschi, V. [Applied Laser Spectroscopy Laboratory, Institute of Chemistry of Organometallic Compounds, National Research Council (CNR), Pisa I-56124 (Italy); Canals, A. [Department of Analytical Chemistry and Food Science and University Institute of Materials, Faculty of Science, University of Alicante, Alicante E-03080 (Spain)

    2013-01-01

    In this work, the possibility of using Laser-Induced Breakdown Spectrometry (LIBS) combined with liquid–liquid microextraction techniques is evaluated as a simple and fast method for trace elemental analysis. Two different strategies for LIBS analysis of manganese contained in microdroplets of extraction solvent (Triton X-114) are studied: (i) analysis by direct laser irradiation of microdroplets; and (ii) analysis by laser irradiation of microdroplets dried on metallic substrates (surface-enhanced LIBS — SENLIBS). Experiments were carried out using synthetic samples with different concentrations of manganese in a 10% w/w Triton X-114 matrix. The analysis by direct laser irradiation of microdroplets showed low precision, sensitivity and poor linearity across the concentration range evaluated (R{sup 2} < 0.95). On the other hand, the SENLIBS method of analysis improved the sensitivity, the precision and the linearity of the calibration curve with respect to the direct analysis of microdroplets. In comparison with experimental results obtained by direct analysis, SENLIBS also allowed several replicate measurements to be carried out in a single microdroplet. The limit of detection obtained was 6 μg g{sup −1} of Mn. - Highlights: ► LIBS combined with microextraction procedures for trace analysis is proposed. ► The proposed combination depends on LIBS ability to analyze sample microvolumes. ► A surface-enhanced LIBS methodology for microdroplet analysis was evaluated. ► Results indicate this combination to be promising for trace analysis in liquids.

  8. Application of picosecond laser-induced breakdown spectroscopy to quantitative analysis of boron in meatballs and other biological samples.

    Science.gov (United States)

    Hedwig, Rinda; Lahna, Kurnia; Lie, Zener Sukra; Pardede, Marincan; Kurniawan, Koo Hendrik; Tjia, May On; Kagawa, Kiichiro

    2016-11-10

    This report presents the results of laser-induced breakdown spectroscopy (LIBS) study on biological and food samples of high water content using a picosecond (ps) laser at low output energy of 10 mJ and low-pressure helium ambient gas at 2 kPa. Evidence of excellent emission spectra of various analyte elements with very low background is demonstrated for a variety of samples without the need of sample pretreatment. Specifically, limits of detection in the range of sub-ppm are obtained for hazardous Pb and B impurities in carrots and meatballs. This study also shows the inferior performance of LIBS using a nanosecond laser and atmospheric ambient air for a soft sample of high water content and thereby explains its less successful applications in previous attempts. The present result has instead demonstrated the feasibility and favorable results of employing LIBS with a ps laser and low-pressure helium ambient gas as a less costly and more practical alternative to inductively coupled plasma for regular high sensitive inspection of harmful food preservatives and environmental pollutants.

  9. Controlled calibration method for laser induced breakdown spectroscopy

    Institute of Scientific and Technical Information of China (English)

    Li Wang; Chijian Zhang; Yuan Feng

    2008-01-01

    Laser induced breakdown spectroscopy (LIBS) is a potential technique for rapid analysis of samples present in solids, gases and liquids. In the last two decades it was an object of extensive studies. Controlled calibration method used to analysis the LIBS spectra is investigated. Compared with the inner calibration and calibration-free (CF) methods, this new method overcomes "matrix effect", and demonstrates a better ability to cope with the spectra. It is used to analyze natural soil, and errors of the concentration are decreased about 5%. The result shows that the new method is feasible and accurate.

  10. Biomedical and environmental applications of laser-induced breakdown spectroscopy

    Indian Academy of Sciences (India)

    V K Unnikrishnan; K S Choudhari; Suresh D Kulkarni; Rajesh Nayak; V B Kartha; C Santhosh; B M Suri

    2014-02-01

    Laser-induced breakdown spectroscopy (LIBS) is an emerging analytical technique with numerous advantages such as rapidity, multi-elemental analysis, minimal sample preparation, minimal destruction, low cost and versatility of being applied to a wide range of materials. In this paper, we report the preliminary observations we obtained using LIBS for clinical and environmental samples. Elemental analysis has been done qualitatively in human teeth samples which show encouraging results. It has also been demonstrated in this paper that LIBS can be very well utilized in field applications such as plastic waste sorting and recycling.

  11. Investigation of the Matrix Effect on the Accuracy of Quantitative Analysis of Trace Metals in Liquids Using Laser-Induced Breakdown Spectroscopy with Solid Substrates.

    Science.gov (United States)

    Xiu, Junshan; Dong, Lili; Qin, Hua; Liu, Yunyan; Yu, Jin

    2016-12-01

    The detection limit of trace metals in liquids has been improved greatly by laser-induced breakdown spectroscopy (LIBS) using solid substrate. A paper substrate and a metallic substrate were used as a solid substrate for the detection of trace metals in aqueous solutions and viscous liquids (lubricating oils) respectively. The matrix effect on quantitative analysis of trace metals in two types of liquids was investigated. For trace metals in aqueous solutions using paper substrate, the calibration curves established for pure solutions and mixed solutions samples presented large variation on both the slope and the intercept for the Cu, Cd, and Cr. The matrix effects among the different elements in mixed solutions were observed. However, good agreement was obtained between the measured and known values in real wastewater. For trace metals in lubricating oils, the matrix effect between the different oils is relatively small and reasonably negligible under the conditions of our experiment. A universal calibration curve can be established for trace metals in different types of oils. The two approaches are verified that it is possible to develop a feasible and sensitive method with accuracy results for rapid detection of trace metals in industrial wastewater and viscous liquids by laser-induced breakdown spectroscopy.

  12. Progress in fieldable laser-induced breakdown spectroscopy (LIBS)

    Science.gov (United States)

    Miziolek, Andrzej W.

    2012-06-01

    In recent years there has been great progress in the Laser Induced Breakdown Spectroscopy (LIBS) technology field. Significant advances have been made both in fundamental and applied research as well as in data processing/chemometrics. Improvements in components, most notably lasers/optics and spectrometers are enabling the development of new devices that are suitable for field use. These new commercial devices recently released to the marketplace, as well as ones currently under development, are bringing the potential of LIBS for CBRNE threat analysis into real-world applications.

  13. Compact High Sensitive Laser-Induced Breakdown Spectroscopy Instrument Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Laser induced breakdown spectroscopy (LIBS) is a versatile tool for in situ substance characterization. Existing LIBS instruments are not compact enough for space...

  14. Laser-Induced Breakdown Spectroscopy: Capabilities and Applications

    Science.gov (United States)

    2010-07-01

    sample preparation. 14 6. References 1. Cremers D.A.; Radziemski, L. J. Handbook of Laser-Induced Breakdown Spectroscopy; West Sussex, England...30 (21), 2882–2884. 17. Salle, B.; Lacour, J. L.; Vors, E.; Fichet, P.; Maurice, S.; Cremers , D. A.; et al. Laser- Induced Breakdown Spectroscopy...90. Martin , M. Z.; Labbe, N.; Andre, N.; Harris, R.; Ebinger, M.; Wullschleger, S. D.; et al. High Resolution Applications of Laser-Induced

  15. Development of a mobile system based on laser-induced breakdown spectroscopy and dedicated to in situ analysis of polluted soils

    Energy Technology Data Exchange (ETDEWEB)

    Bousquet, B. [Centre de Physique Moleculaire Optique et Hertzienne (CPMOH), Universite Bordeaux 1, 351 cours de la Liberation, 33405 Talence Cedex (France)], E-mail: bruno.bousquet@u-bordeaux1.fr; Travaille, G.; Ismael, A.; Canioni, L. [Centre de Physique Moleculaire Optique et Hertzienne (CPMOH), Universite Bordeaux 1, 351 cours de la Liberation, 33405 Talence Cedex (France); Michel-Le Pierres, K.; Brasseur, E.; Roy, S. [BRGM. Service MMA. 3 av. Claude Guillemin. 45060 Orleans (France); Le Hecho, I.; Larregieu, M.; Tellier, S.; Potin-Gautier, M. [Laboratoire de Chimie Analytique BioInorganique et Environnement (LCABIE), Institut Pluridisciplinaire de Recherche sur l' Environnement et les Materiaux (IPREM) UMR CNRS 5254, Technopole Helioparc, 2 av. Pierre Angot 64053 Pau Cedex 9 (France); Boriachon, T.; Wazen, P.; Diard, A. [QUANTEL, 2 bis Avenue du Pacifique, 91941 Les Ulis, Cedex (France); Belbeze, S. [ANTEA, 3, avenue Claude Guillemin, B.P. 66119, 45061 Orleans Cedex 2 (France)

    2008-10-15

    Principal Components Analysis (PCA) is successfully applied to the full laser-induced breakdown spectroscopy (LIBS) spectra of soil samples, defining classes according to the concentrations of the major elements. The large variability of the LIBS data is related to the heterogeneity of the samples and the representativeness of the data is finally discussed. Then, the development of a mobile LIBS system dedicated to the in-situ analysis of soils polluted by heavy metals is described. Based on the use of ten-meter long optical fibers, the mobile system allows deported measurements. Finally, the laser-assisted drying process studied by the use of a customized laser has not been retained to overcome the problem of moisture.

  16. Homogeneity testing and quantitative analysis of manganese (Mn in vitrified Mn-doped glasses by laser-induced breakdown spectroscopy (LIBS

    Directory of Open Access Journals (Sweden)

    V. K. Unnikrishnan

    2014-09-01

    Full Text Available Laser-induced breakdown spectroscopy (LIBS, an atomic emission spectroscopy method, has rapidly grown as one of the best elemental analysis techniques over the past two decades. Homogeneity testing and quantitative analysis of manganese (Mn in manganese-doped glasses have been carried out using an optimized LIBS system employing a nanosecond ultraviolet Nd:YAG laser as the source of excitation. The glass samples have been prepared using conventional vitrification methods. The laser pulse irradiance on the surface of the glass samples placed in air at atmospheric pressure was about 1.7×109 W/cm2. The spatially integrated plasma emission was collected and imaged on to the spectrograph slit using an optical-fiber-based collection system. Homogeneity was checked by recording LIBS spectra from different sites on the sample surface and analyzing the elemental emission intensities for concentration determination. Validation of the observed LIBS results was done by comparison with scanning electron microscope- energy dispersive X-ray spectroscopy (SEM-EDX surface elemental mapping. The analytical performance of the LIBS system has been evaluated through the correlation of the LIBS determined concentrations of Mn with its certified values. The results are found to be in very good agreement with the certified concentrations.

  17. Homogeneity testing and quantitative analysis of manganese (Mn) in vitrified Mn-doped glasses by laser-induced breakdown spectroscopy (LIBS)

    Energy Technology Data Exchange (ETDEWEB)

    Unnikrishnan, V. K.; Nayak, Rajesh; Kartha, V. B.; Santhosh, C., E-mail: santhosh.cls@manipal.edu, E-mail: unnikrishnan.vk@manipal.edu [Department of Atomic and Molecular Physics, Manipal University, Manipal (India); Sonavane, M. S. [Nuclear Recycle Board, Bhabha Atomic Research Centre, Mumbai (India); Yeotikar, R. G. [Process Development Division, Bhabha Atomic Research Centre, Mumbai (India); Shah, M. L.; Gupta, G. P.; Suri, B. M. [Laser and Plasma Technology Division, Bhabha Atomic Research Centre, Mumbai (India)

    2014-09-15

    Laser-induced breakdown spectroscopy (LIBS), an atomic emission spectroscopy method, has rapidly grown as one of the best elemental analysis techniques over the past two decades. Homogeneity testing and quantitative analysis of manganese (Mn) in manganese-doped glasses have been carried out using an optimized LIBS system employing a nanosecond ultraviolet Nd:YAG laser as the source of excitation. The glass samples have been prepared using conventional vitrification methods. The laser pulse irradiance on the surface of the glass samples placed in air at atmospheric pressure was about 1.7×10{sup 9} W/cm{sup 2}. The spatially integrated plasma emission was collected and imaged on to the spectrograph slit using an optical-fiber-based collection system. Homogeneity was checked by recording LIBS spectra from different sites on the sample surface and analyzing the elemental emission intensities for concentration determination. Validation of the observed LIBS results was done by comparison with scanning electron microscope- energy dispersive X-ray spectroscopy (SEM-EDX) surface elemental mapping. The analytical performance of the LIBS system has been evaluated through the correlation of the LIBS determined concentrations of Mn with its certified values. The results are found to be in very good agreement with the certified concentrations.

  18. Laser-induced breakdown spectroscopy theory and applications

    CERN Document Server

    Perini, Umberto

    2014-01-01

    This book deals with the Laser-Induced Breakdown Spectroscopy (LIBS), a widely used atomic emission spectroscopy technique for elemental analysis of materials. It is based on the use of a high-power, short pulse laser excitation. The book is divided into two main sections: the first one concerning theoretical aspects of the technique, the second one describing the state of the art in applications of the technique in different scientific/technological areas. Numerous examples of state of the art applications provide the readers an almost complete scenario of the LIBS technique. The LIBS theoretical aspects are reviewed. The book helps the readers who are less familiar with the technique to understand the basic principles. Numerous examples of state of the art applications give an almost complete scenario of the LIBS technique potentiality. These examples of applications may have a strong impact on future industrial utilization. The authors made important contributions to the development of this field.

  19. Laser-induced breakdown spectroscopy fundamentals and applications

    CERN Document Server

    Noll, Reinhard

    2012-01-01

    This book is a comprehensive source of the fundamentals, process parameters, instrumental components and applications of laser-induced breakdown spectroscopy (LIBS). The effect of multiple pulses on material ablation, plasma dynamics and plasma emission is presented. A heuristic plasma modeling allows to simulate complex experimental plasma spectra. These methods and findings form the basis for a variety of applications to perform quantitative multi-element analysis with LIBS. These application potentials of LIBS have really boosted in the last years ranging from bulk analysis of metallic alloys and non-conducting materials, via spatially resolved analysis and depth profiling covering measuring objects in all physical states: gaseous, liquid and solid. Dedicated chapters present LIBS investigations for these tasks with special emphasis on the methodical and instrumental concepts as well as the optimization strategies for a quantitative analysis. Requirements, concepts, design and characteristic features of LI...

  20. Analytical study of seashell using laser-induced breakdown spectroscopy

    Science.gov (United States)

    Ying, LI; Yanhong, GU; Ying, Zhang; Yuandong, LI; Yuan, LU

    2017-02-01

    Seashell has been applied as an indicator for ocean research and element analysis of the seashell is used to track biological or environmental evolution. In this work, laser-induced breakdown spectroscopy (LIBS) was applied for elementary analysis of an ezo scallop-shell, and a graphite enrichment method was used as the assistance. It was found that LIBS signal intensity of Ca fluctuated less than 5%, in spite of the sampling positions, and Sr/Ca was related to the shell growth. A similar variation was also found when using a direct LIBS analysis on the shell surface, and it might be more practicable to track shell growth by investigating Sr/Ca ratio with Sr ionic line at 421.6 nm. The obtained results prove that calcium (Ca) is qualified as an internal reference for shell analysis, and LIBS is a potential analytical method for seashell study.

  1. Effect of pulse repetition rate and number of pulses in the analysis of polypropylene and high density polyethylene by nanosecond infrared laser induced breakdown spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Leme, Flavio O. [Laboratorio de Quimica Analitica ' Henrique Bergamin Filho' , Centro de Energia Nuclear na Agricultura, Universidade de Sao Paulo, Av. Centenario 303, 13416-000 Piracicaba, SP (Brazil); Godoi, Quienly [Laboratorio de Quimica Analitica ' Henrique Bergamin Filho' , Centro de Energia Nuclear na Agricultura, Universidade de Sao Paulo, Av. Centenario 303, 13416-000 Piracicaba, SP (Brazil); Departamento de Quimica, Universidade Federal de Sao Carlos, Rod. Washington Luis, km 235, 13565-905 Sao Carlos, SP (Brazil); Kiyataka, Paulo H.M. [Centro de Tecnologia de Embalagens, Instituto de Tecnologia de Alimentos, Av. Brasil 2880, 13070-178 Campinas, SP (Brazil); Santos, Dario [Departamento de Ciencias Exatas e da Terra, Universidade Federal de Sao Paulo, Rua Prof. Artur Riedel 275, 09972-270 Diadema, SP (Brazil); Agnelli, Jose A.M. [Departamento de Engenharia de Materiais, Universidade Federal de Sao Carlos, Rod. Washington Luis, km 235, 13565-905 Sao Carlos, SP (Brazil); and others

    2012-02-01

    Pulse repetition rates and the number of laser pulses are among the most important parameters that do affect the analysis of solid materials by laser induced breakdown spectroscopy, and the knowledge of their effects is of fundamental importance for suggesting analytical strategies when dealing with laser ablation processes of polymers. In this contribution, the influence of these parameters in the ablated mass and in the features of craters was evaluated in polypropylene and high density polyethylene plates containing pigment-based PbCrO{sub 4}. Surface characterization and craters profile were carried out by perfilometry and scanning electron microscopy. Area, volume and profile of craters were obtained using Taylor Map software. A laser induced breakdown spectroscopy system consisted of a Q-Switched Nd:YAG laser (1064 nm, 5 ns) and an Echelle spectrometer equipped with ICCD detector were used. The evaluated operating conditions consisted of 10, 25 and 50 laser pulses at 1, 5 and 10 Hz, 250 mJ/pulse (85 J cm{sup -2}), 2 {mu}s delay time and 6 {mu}s integration time gate. Differences in the topographical features among craters of both polymers were observed. The decrease in the repetition rate resulted in irregular craters and formation of edges, especially in polypropylene sample. The differences in the topographical features and ablated masses were attributed to the influence of the degree of crystallinity, crystalline melting temperature and glass transition temperature in the ablation process of the high density polyethylene and polypropylene. It was also observed that the intensities of chromium and lead emission signals obtained at 10 Hz were two times higher than at 5 Hz by keeping the number of laser pulses constant.

  2. Analysis of Laser Breakdown Data

    Science.gov (United States)

    Becker, Roger

    2009-03-01

    Experiments on laser breakdown for ns pulses of 532 nm or 1064 nm light in water and dozens of simple hydrocarbon liquids are analyzed and compared to widely-used models and other laser breakdown experiments reported in the literature. Particular attention is given to the curve for the probability of breakdown as a function of the laser fluence at the beam focus. Criticism is made of the na"ive forms of both ``avalanche'' breakdown and multi-photon breakdown. It appears that the process is complex and is intimately tied to the chemical group of the material. Difficulties with developing an accurate model of laser breakdown in liquids are outlined.

  3. Spectrum standardization for laser-induced breakdown spectroscopy measurements

    CERN Document Server

    Wang, Zhe; West, Logan; Li, Zheng; Ni, Weidou

    2011-01-01

    This paper presents a spectra normalization method for laser-induced breakdown spectroscopy (LIBS) measurements by converting the recorded characteristic line intensity at varying conditions to the intensity under a standard condition with standard plasma temperature, degree of ionization, and total number density of the interested species to reduce the measurement uncertainty. The characteristic line intensities of the interested species are first converted to the intensity at a fixed temperature and standard degree of ionization but varying total number density for each laser pulse analysis. Under this state, if the influence of the variation of plasma morphology is neglected, the sum of multiple spectral line intensities for the measured element can be regarded proportional to the total number density of the specific element, and the fluctuation of the total number density, or the variation of ablation mass, was compensated for by the application of this relationship. In the experiments with 29 brass alloy...

  4. Detection of early caries by laser-induced breakdown spectroscopy

    Science.gov (United States)

    Sasazawa, Shuhei; Kakino, Satoko; Matsuura, Yuji

    2015-07-01

    To improve sensitivity of dental caries detection by laser-induced breakdown spectroscopy (LIBS) analysis, it is proposed to utilize emission peaks in the ultraviolet. We newly focused on zinc whose emission peaks exist in ultraviolet because zinc exists at high concentration in the outer layer of enamel. It was shown that by using ratios between heights of an emission peak of Zn and that of Ca, the detection sensitivity and stability are largely improved. It was also shown that early caries are differentiated from healthy part by properly setting a threshold in the detected ratios. The proposed caries detection system can be applied to dental laser systems such as ones based on Er:YAG-lasers. When ablating early caries part by laser light, the system notices the dentist that the ablation of caries part is finished. We also show the intensity of emission peaks of zinc decreased with ablation with Er:YAG laser light.

  5. Double pulse laser induced breakdown spectroscopy: A potential tool for the analysis of contaminants and macro/micronutrients in organic mineral fertilizers.

    Science.gov (United States)

    Nicolodelli, Gustavo; Senesi, Giorgio Saverio; de Oliveira Perazzoli, Ivan Luiz; Marangoni, Bruno Spolon; De Melo Benites, Vinícius; Milori, Débora Marcondes Bastos Pereira

    2016-09-15

    Organic fertilizers are obtained from waste of plant or animal origin. One of the advantages of organic fertilizers is that, from the composting, it recycles waste-organic of urban and agriculture origin, whose disposal would cause environmental impacts. Fast and accurate analysis of both major and minor/trace elements contained in organic mineral and inorganic fertilizers of new generation have promoted the application of modern analytical techniques. In particular, laser induced breakdown spectroscopy (LIBS) is showing to be a very promising, quick and practical technique to detect and measure contaminants and nutrients in fertilizers. Although, this technique presents some limitations, such as a low sensitivity, if compared to other spectroscopic techniques, the use of double pulse (DP) LIBS is an alternative to the conventional LIBS in single pulse (SP). The macronutrients (Ca, Mg, K, P), micronutrients (Cu, Fe, Na, Mn, Zn) and contaminant (Cr) in fertilizer using LIBS in SP and DP configurations were evaluated. A comparative study for both configurations was performed using optimized key parameters for improving LIBS performance. The limit of detection (LOD) values obtained by DP LIBS increased up to seven times as compared to SP LIBS. In general, the marked improvement obtained when using DP system in the simultaneous LIBS quantitative determination for fertilizers analysis could be ascribed to the larger ablated mass of the sample. The results presented in this study show the promising potential of the DP LIBS technique for a qualitative analysis in fertilizers, without requiring sample preparation with chemical reagents.

  6. Dispersive liquid–liquid microextraction for metals enrichment: A useful strategy for improving sensitivity of laser-induced breakdown spectroscopy in liquid samples analysis

    OpenAIRE

    Aguirre Pastor, Miguel Ángel; Selva, E.J.; Hidalgo, Montserrat; Canals, Antonio

    2015-01-01

    A rapid and efficient Dispersive Liquid–Liquid Microextraction (DLLME) followed by Laser-Induced Breakdown Spectroscopy detection (LIBS) was evaluated for simultaneous determination of Cr, Cu, Mn, Ni and Zn in water samples. Metals in the samples were extracted with tetrachloromethane as pyrrolidinedithiocarbamate (APDC) complexes, using vortex agitation to achieve dispersion of the extractant solvent. Several DLLME experimental factors affecting extraction efficiency were optimized with a mu...

  7. Laser-Induced Breakdown Spectroscopy and Chlorophyll a Flourescence Transients

    DEFF Research Database (Denmark)

    Frydenvang, Jens

    of a sufficient quality; something that remains a problem for many in-situ methods. In my PhD, I present my work with two such in-situ methods, Laser-Induced Breakdown Spectroscopy (LIBS) and OJIP transients, the rising part of chlorophyll a fluorescence transients from dark-adapted leaves....

  8. Analysis of the polymeric fractions of scrap from mobile phones using laser-induced breakdown spectroscopy: chemometric applications for better data interpretation.

    Science.gov (United States)

    Aquino, Francisco W B; Pereira-Filho, Edenir R

    2015-03-01

    Because of their short life span and high production and consumption rates, mobile phones are one of the contributors to WEEE (waste electrical and electronic equipment) growth in many countries. If incorrectly managed, the hazardous materials used in the assembly of these devices can pollute the environment and pose dangers for workers involved in the recycling of these materials. In this study, 144 polymer fragments originating from 50 broken or obsolete mobile phones were analyzed via laser-induced breakdown spectroscopy (LIBS) without previous treatment. The coated polymers were mainly characterized by the presence of Ag, whereas the uncoated polymers were related to the presence of Al, K, Na, Si and Ti. Classification models were proposed using black and white polymers separately in order to identify the manufacturer and origin using KNN (K-nearest neighbor), SIMCA (Soft Independent Modeling of Class Analogy) and PLS-DA (Partial Least Squares for Discriminant Analysis). For the black polymers the percentage of correct predictions was, in average, 58% taking into consideration the models for manufacturer and origin identification. In the case of white polymers, the percentage of correct predictions ranged from 72.8% (PLS-DA) to 100% (KNN).

  9. In-situ analysis of the first wall by laser-induced breakdown spectroscopy in the TEXTOR tokamak: Dependence on the magnetic field strength

    Energy Technology Data Exchange (ETDEWEB)

    Xiao, Q., E-mail: qingmeierin@126.com [Key Laboratory of Materials Modification by Laser, Ion and Electron Beams, Chinese Ministry of Education, School of Physics and Optical Electronic Technology, Dalian University of Technology, Dalian 116024 (China); Hai, R. [Key Laboratory of Materials Modification by Laser, Ion and Electron Beams, Chinese Ministry of Education, School of Physics and Optical Electronic Technology, Dalian University of Technology, Dalian 116024 (China); Ding, H., E-mail: hding@dlut.edu.cn [Key Laboratory of Materials Modification by Laser, Ion and Electron Beams, Chinese Ministry of Education, School of Physics and Optical Electronic Technology, Dalian University of Technology, Dalian 116024 (China); Huber, A.; Philipps, V.; Gierse, N.; Sergienko, G. [Institute of Energy and Climate Research – Plasma Physics, Forschungszentrum Jülich GmbH, Association EURATOM-FZJ, Partner in the Trilateral Euregio Cluster, D52425 Jülich (Germany)

    2015-08-15

    Laser-induced breakdown spectroscopy (LIBS) is considered as a promising method for in-situ diagnostic of the co-deposition and fuel retention during and in between plasma discharges in fusion devices. LIBS has been investigated intensively under laboratory conditions, while the application of LIBS in fusion devices is still in early stages. Moreover, the LIB processes are influenced by additional conditions in fusion devices, particularly the magnetic field. The experiments in TEXTOR show a significant enhancement in the spectral line emission and a deeper penetration of the laser-produced plasma into the edge plasma in the presence of magnetic field. These effects can be attributed to an increased confinement of the plasma by the magnetic field. The interference of magnetic field may compromise the quantitative interpretation of LIB spectra. Therefore, quantitative analysis of ITER-like co-deposits was done in laboratory without magnetic field as well as in TEXTOR with a magnetic field of Bt ∼ 2.25 T.

  10. Application of Laser Induced Breakdown Spectroscopy under Polar Conditions

    Science.gov (United States)

    Clausen, J. L.; Hark, R.; Bol'shakov, A.; Plumer, J.

    2015-12-01

    Over the past decade our research team has evaluated the use of commercial-off-the-shelf laser-induced breakdown spectroscopy (LIBS) for chemical analysis of snow and ice samples under polar conditions. One avenue of research explored LIBS suitability as a detector of paleo-climate proxy indicators (Ca, K, Mg, and Na) in ice as it relates to atmospheric circulation. LIBS results revealed detection of peaks for C and N, consistent with the presence of organic material, as well as major ions (Ca, K, Mg, and Na) and trace metals (Al, Cu, Fe, Mn, Ti). The detection of Ca, K, Mg, and Na confirmed that LIBS has sufficient sensitivity to be used as a tool for characterization of paleo-climate proxy indicators in ice-core samples. Techniques were developed for direct analysis of ice as well as indirect measurements of ice via melting and filtering. Pitfalls and issues of direct ice analysis using several cooling techniques to maintain ice integrity will be discussed. In addition, a new technique, laser ablation molecular isotopic spectroscopy (LAMIS) was applied to detection of hydrogen and oxygen isotopes in ice as isotopic analysis of ice is the main tool in paleoclimatology and glaciology studies. Our results demonstrated that spectra of hydroxyl isotopologues 16OH, 18OH, and 16OD can be recorded with a compact spectrograph to determine hydrogen and oxygen isotopes simultaneously. Quantitative isotopic calibration for ice analysis can be accomplished using multivariate chemometric regression as previously realized for water vapor. Analysis with LIBS and LAMIS required no special sample preparation and was about ten times faster than analysis using ICP-MS. Combination of the two techniques in one portable instrument for in-field analysis appears possible and would eliminate the logistical and cost issues associated with ice core management.

  11. Comparative investigation of laser ablation plumes in air and argon by analysis of spectral line shapes: Insights on calibration-free laser-induced breakdown spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Hermann, Jörg, E-mail: hermann@lp3.univ-mrs.fr [LP3, CNRS — Aix Marseille University, 163 Av. de Luminy, 13288 Marseille (France); Gerhard, Christoph [Laboratory of Laser and Plasma Technologies, University of Applied Sciences and Arts, Von-Ossietzky-Straße 99, 37085 Göttingen (Germany); Axente, Emanuel [Laser–Surface–Plasma Interactions Laboratory, Lasers Department, National Institute for Lasers, Plasma and Radiation Physics, Măgurele (Romania); Dutouquet, Christophe [Institut National de l' Environnement Industriel et des Risques (INERIS/DRC/CARA/NOVA), Parc Technologique Alata, BP 2, 60550 Verneuil-En-Halatte (France)

    2014-10-01

    We investigate the characteristic features of plume expansion in air and argon resulting from ultraviolet laser ablation of solid matter in conditions typically applied in material analysis via laser-induced breakdown spectroscopy (LIBS). Barite crown glass is chosen as a target material for the characteristic emission spectrum suitable for plasma diagnostics. The space-integrated plasma emission spectrum recorded with an echelle spectrometer coupled to a gated detector is compared to the computed spectral radiance of a nonuniform plasma in local thermodynamic equilibrium. In particular, resonance lines of neutral sodium atoms and barium ions are observed to probe gradients of temperature and density within the plume. It is shown that laser ablation in argon leads to an almost uniform plasma whereas gradients of temperature and density are evidenced in ambient air. The discrepancy is attributed to the different physical properties of both gases leading to a stronger vapor–gas energy exchange in the case of air. However, strong gradients occur only in a thin peripheral zone, close to the vapor–gas contact front. The larger plasma core appears almost uniform. The peripheral zone of low temperature mostly contributes to the plasma emission spectrum by absorption and material analysis via calibration-free LIBS in air may ignore the nonuniform character of the plasma if only transitions of small optical thickness are considered. - Highlights: • Investigation of laser ablation plumes by analysis of spectral line shapes • Simulation of emission spectra from nonuniform laser-produced plasma • Plasma is more uniform for ablation in argon. • Plasma nonuniformity mostly affects optically thick lines. • Calibration-free LIBS may ignore gradients if optically thin lines are chosen.

  12. Measurement of Irradiated Pyroprocessing Samples via Laser Induced Breakdown Spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Phongikaroon, Supathorn [Virginia Commonwealth Univ., Richmond, VA (United States)

    2016-10-31

    The primary objective of this research is to develop an applied technology and provide an assessment to remotely measure and analyze the real time or near real time concentrations of used nuclear fuel (UNF) dissolute in electrorefiners. Here, Laser-Induced Breakdown Spectroscopy (LIBS), in UNF pyroprocessing facilities will be investigated. LIBS is an elemental analysis method, which is based on the emission from plasma generated by focusing a laser beam into the medium. This technology has been reported to be applicable in the media of solids, liquids (includes molten metals), and gases for detecting elements of special nuclear materials. The advantages of applying the technology for pyroprocessing facilities are: (i) Rapid real-time elemental analysis|one measurement/laser pulse, or average spectra from multiple laser pulses for greater accuracy in < 2 minutes; (ii) Direct detection of elements and impurities in the system with low detection limits|element specific, ranging from 2-1000 ppm for most elements; and (iii) Near non-destructive elemental analysis method (about 1 g material). One important challenge to overcome is achieving high-resolution spectral analysis to quantitatively analyze all important fission products and actinides. Another important challenge is related to accessibility of molten salt, which is heated in a heavily insulated, remotely operated furnace in a high radiation environment with an argon atmosphere.

  13. Laser-induced breakdown spectroscopy of tantalum plasma

    Energy Technology Data Exchange (ETDEWEB)

    Khan, Sidra; Bashir, Shazia; Hayat, Asma; Khaleeq-ur-Rahman, M.; Faizan–ul-Haq [Centre for Advanced Studies in Physics, GC University, Lahore (Pakistan)

    2013-07-15

    Laser Induced Breakdown spectroscopy (LIBS) of Tantalum (Ta) plasma has been investigated. For this purpose Q-switched Nd: YAG laser pulses (λ∼ 1064 nm, τ∼ 10 ns) of maximum pulse energy of 100 mJ have been employed as an ablation source. Ta targets were exposed under the ambient environment of various gases of Ar, mixture (CO{sub 2}: N{sub 2}: He), O{sub 2}, N{sub 2}, and He under various filling pressure. The emission spectrum of Ta is observed by using LIBS spectrometer. The emission intensity, excitation temperature, and electron number density of Ta plasma have been evaluated as a function of pressure for various gases. Our experimental results reveal that the optical emission intensity, the electron temperature and density are strongly dependent upon the nature and pressure of ambient environment. The SEM analysis of the ablated Ta target has also been carried out to explore the effect of ambient environment on the laser induced grown structures. The growth of grain like structures in case of molecular gases and cone-formation in case of inert gases is observed. The evaluated plasma parameters by LIBS analysis such as electron temperature and the electron density are well correlated with the surface modification of laser irradiated Ta revealed by SEM analysis.

  14. Enhancing the analytical performance of laser-induced breakdown spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Cremers, D.A.; Chinni, R.C.; Pichahchy, A.E.; Thornquist, H.K.

    1998-12-31

    This is the final report of a one-year, Laboratory Directed Research and Development (LDRD) project at Los Alamos National Laboratory (LANL). The objective of this work is to enhance the analytical capabilities of laser-induced breakdown spectroscopy (LIBS). LIBS is a method of elemental analysis in which powerful laser pulses are focused on a sample to form a microplasma. LIBS is perhaps the most versatile elemental analysis method, applicable to a variety of different real-world analysis problems. Therefore, it is important to enhance the capabilities of the method as much as possible. Accomplishments include: (1) demonstration of signal enhancements of 5--30 times from soils and metals using a double pulse method; (2) development of a model of the observed enhancement obtained using double pulses; (3) demonstration that the analytical performance achievable using low laser-pulse energies (10 and 25 mJ) can match that achievable using an energy of 100 mJ; and (4) demonstration that time-gated detection is not necessary with LIBS.

  15. A model combining spectrum standardization and dominant factor based partial least square method for carbon analysis in coal using laser-induced breakdown spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Li, Xiongwei; Wang, Zhe, E-mail: zhewang@tsinghua.edu.cn; Fu, Yangting; Li, Zheng; Ni, Weidou

    2014-09-01

    Quantitative measurement of carbon content in coal is essentially important for coal property analysis. However, quantitative measurement of carbon content in coal using laser-induced breakdown spectroscopy (LIBS) suffered from low measurement accuracy due to measurement uncertainty as well as the matrix effects. In this study, our previously proposed spectrum standardization method and dominant factor based partial least square (PLS) method were combined to improve the measurement accuracy of carbon content in coal using LIBS. The combination model utilized the spectrum standardization method to accurately calculate dominant carbon concentration as the dominant factor, and then applied PLS with full spectrum information to correct residual errors. The combination model was applied to measure the carbon content in 24 bituminous coal samples. Results demonstrated that the combination model can further improve measurement accuracy compared with the spectrum standardization model and the dominant factor based PLS model, in which the dominant factor was calculated using traditional univariate method. The coefficient of determination, root-mean-square error of prediction, and average relative error for the combination model were 0.99, 1.63%, and 1.82%, respectively. The values for the spectrum standardization model were 0.90, 2.24%, and 2.75%, respectively, whereas those for the dominant factor based PLS model were 0.99, 2.66%, and 3.64%, respectively. The results indicate that LIBS has great potential to be applied for the coal analysis. - Highlights: • Spectrum standardization method is utilized to establish a more accurate dominant factor model. • PLS algorithm is applied to further compensate for residual errors using the entire spectrum information. • Measurement accuracy is improved.

  16. Comparative investigation of partial least squares discriminant analysis and support vector machines for geological cuttings identification using laser-induced breakdown spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Tian, Ye; Wang, Zhennan [Optics and Optoelectronics Laboratory, Ocean University of China, Qingdao, Shandong 266100 (China); Han, Xiaoshuang [Optics and Optoelectronics Laboratory, Ocean University of China, Qingdao, Shandong 266100 (China); College of Electronic Information Engineering, Inner Mongolia University, Hohhot, Inner Mongolia 010021 (China); Hou, Huaming [Optics and Optoelectronics Laboratory, Ocean University of China, Qingdao, Shandong 266100 (China); Zheng, Ronger, E-mail: rzheng@ouc.edu.cn [Optics and Optoelectronics Laboratory, Ocean University of China, Qingdao, Shandong 266100 (China)

    2014-12-01

    With the hope of applying laser-induced breakdown spectroscopy (LIBS) to the geological logging field, a series of cutting samples were classified using LIBS coupled with chemometric methods. In this paper, we focused on a comparative investigation of the linear PLS-DA method and non-linear SVM method. Both the optimal PLS-DA model and SVM model were built by the leave-one-out cross-validation (LOOCV) approach with the calibration LIBS spectra, and then tested by validation spectra. We show that the performance of SVM is significantly better than PLS-DA because of its ability to address the non-linear relationships in LIBS spectra, with a correct classification rate of 91.67% instead of 68.34%, and an unclassification rate of 3.33% instead of 28.33%. To further improve the classification accuracy, we then designed a new classification approach by the joint analysis of PLS-DA and SVM models. With this method, 95% of the validation spectra are correctly classified and no unclassified spectra are observed. This work demonstrated that the coupling of LIBS with the non-linear SVM method has great potential to be used for on-line classification of geological cutting samples, and the combination of PLS-DA and SVM enables the cuttings identification with an excellent performance. - Highlights: • The geological cuttings were classified using LIBS coupled with chemometric methods. • The non-linear SVM showed significantly better performance than PLS-DA. • The joint analysis of PLS-DA and SVMs provided an excellent accuracy of 95%.

  17. Classical univariate calibration and partial least squares for quantitative analysis of brass samples by laser-induced breakdown spectroscopy

    Science.gov (United States)

    Andrade, Jose Manuel; Cristoforetti, Gabriele; Legnaioli, Stefano; Lorenzetti, Giulia; Palleschi, Vincenzo; Shaltout, Abdallah A.

    2010-08-01

    In this work we compare the analytical results obtained by traditional calibration curves (CC) and multivariate Partial Least Squares (PLS) algorithm when applied to the LIBS spectra obtained from ten brass samples (nine standards of known composition and one 'unknown'). Both major (Cu and Zn) and trace (Sn, Pb, Fe) elements in the sample matrix were analyzed. After the analysis, the composition of the 'unknown' sample, measured by X-ray Fluorescence (XRF) technique, was revealed. The predicted concentrations of major elements obtained by rapid PLS algorithms are in very good agreement with the nominal concentrations, as well as with those obtained by the more time-consuming CC approach. A discussion about the possible effects leading to discrepancies of the results is reported. The results of this study open encouraging perspectives towards the development of cheap LIBS instrumentation which would be capable, despite the limitations of the experimental apparatus, to perform fast and precise quantitative analysis on complex samples.

  18. [Analysis of software for identifying spectral line of laser-induced breakdown spectroscopy based on LabVIEW].

    Science.gov (United States)

    Hu, Zhi-yu; Zhang, Lei; Ma, Wei-guang; Yan, Xiao-juan; Li, Zhi-xin; Zhang, Yong-zhi; Wang, Le; Dong, Lei; Yin, Wang-bao; Jia, Suo-tang

    2012-03-01

    Self-designed identifying software for LIBS spectral line was introduced. Being integrated with LabVIEW, the soft ware can smooth spectral lines and pick peaks. The second difference and threshold methods were employed. Characteristic spectrum of several elements matches the NIST database, and realizes automatic spectral line identification and qualitative analysis of the basic composition of sample. This software can analyze spectrum handily and rapidly. It will be a useful tool for LIBS.

  19. Forensic analysis of printing inks using tandem Laser Induced Breakdown Spectroscopy and Laser Ablation Inductively Coupled Plasma Mass Spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Subedi, Kiran, E-mail: ksube001@fiu.edu; Trejos, Tatiana, E-mail: trejost@fiu.edu; Almirall, José, E-mail: almirall@fiu.edu

    2015-01-01

    Elemental analysis, using either LA-ICP-MS or LIBS, can be used for the chemical characterization of materials of forensic interest to discriminate between source materials originating from different sources and also for the association of materials known to originate from the same source. In this study, a tandem LIBS/LA-ICP-MS system that combines the benefits of both LIBS and LA-ICP-MS was evaluated for the characterization of samples of printing inks (toners, inkjets, intaglio and offset.). The performance of both laser sampling methods is presented. A subset of 9 black laser toners, 10 colored (CMYK) inkjet samples, 12 colored (CMYK) offset samples and 12 intaglio inks originating from different manufacturing sources were analyzed to evaluate the discrimination capability of the tandem method. These samples were selected because they presented a very similar elemental profile by LA-ICP-MS. Although typical discrimination between different ink sources is found to be > 99% for a variety of inks when only LA-ICP-MS was used for the analysis, additional discrimination was achieved by combining the elemental results from the LIBS analysis to the LA-ICP-MS analysis in the tandem technique, enhancing the overall discrimination capability of the individual laser ablation methods. The LIBS measurements of the Ca, Fe, K and Si signals, in particular, improved the discrimination for this specific set of different ink samples previously shown to exhibit very similar LA-ICP-MS elemental profiles. The combination of these two techniques in a single setup resulted in better discrimination of the printing inks with two distinct fingerprint spectra, providing information from atomic/ionic emissions and isotopic composition (m/z) for each ink sample. - Highlights: • The optimization of the parameters for LA-ICP-MS and LIBS in a tandem experiment are presented. • The analytical figures of merit for the tandem experiment for data collected simultaneously, are presented. • A

  20. Laser-induced breakdown spectroscopy with multi-kHz fibre laser for mobile metal analysis tasks — A comparison of different analysis methods and with a mobile spark-discharge optical emission spectroscopy apparatus

    Energy Technology Data Exchange (ETDEWEB)

    Scharun, Michael, E-mail: michael.scharun@ilt.fraunhofer.de [RWTH Aachen University, Chair for Laser Technology, Steinbachstraße 15, Aachen (Germany); Fricke-Begemann, Cord; Noll, Reinhard [Fraunhofer Institute for Laser Technology, Steinbachstraße 15, Aachen (Germany)

    2013-09-01

    The identification and separation of different alloys are a permanent task of crucial importance in the metal recycling industry. Laser-induced breakdown spectroscopy (LIBS) offers important advantages in comparison to the state-of-the-art techniques for this application. For LIBS measurement no additional sample preparation is necessary. The overall analysis time is much smaller than for the state-of-the-art techniques. The LIBS setup presented in this study enables mobile operation with a handheld probe for the analysis of metallic materials. Excitation source is a fibre laser with a repetition rate of 30 kHz and a pulse energy of 1.33 mJ. The compact optical setup allows measurements at almost every point of a sample within 5 ms. The generated plasma light is analysed using a Multi-CCD spectrometer. The broad spectral coverage and high resolution provide an outstanding amount of spectroscopic information thereby enabling a variety of calibration approaches. Using a set of Al-based and a set of Fe-based samples the analytical performance of uni- and multivariate calibrations is evaluated. The same sample sets are analysed with a commercial state-of-the-art spark-discharge optical emission spectrometer allowing an assessment of the achieved results. Even though the possible analytical correctness of the fibre laser based LIBS measurements is found to similar or even better than that of the conventional technique, advantages of the multivariate data evaluation have not yet been realised in the investigations. However, due to the in situ sample preparation and short measurement times, fibre-laser based LIBS offers superior features. - Highlights: • Mobile, hand-guided LIBS apparatus for metal analysis, even for steel • Comparable results as state-of-the-art SD-OES instrument • New sectioned calibration function resulting in smaller deviations • Comparison of univariate and multivariate analysis methods.

  1. Laser-induced breakdown spectroscopy for polymer identification.

    Science.gov (United States)

    Grégoire, Sylvain; Boudinet, Marjorie; Pelascini, Frédéric; Surma, Fabrice; Detalle, Vincent; Holl, Yves

    2011-07-01

    This study aims at differentiating several organic materials, particularly polymers, by laser induced breakdown spectroscopy. The goal is to apply this technique to the fields of polymer recycling and cultural heritage conservation. We worked with some usual polymers families: polyethylene (PE), polypropylene (PP), polyoxymethylene, (POM), poly(vinyl chloride), polytetrafluoroethylene, polyoxyethylene (POE), and polyamide for the aliphatic ones, and poly(butylene terephthalate), acrylonitrile-butadiene-styrene, polystyrene, and polycarbonate for the aromatic ones. The fourth harmonic of a Nd:YAG laser (266 nm) in ambient air at atmospheric pressure was used. A careful analysis of the C(2) Swan system (0,0) band in polymers containing no C-C (POM), few C-C (POE), or aromatic C-C linkages led us to the conclusion that the C(2) signal might be native, i.e., the result of direct ablation from the sample. With use of these results, aliphatic and aromatic polymers could be differentiated. Further data treatments, such as properly chosen line ratios, principal component analysis, and partial least squares regression, were evaluated. It was shown that many polymers could be separated, including PE and PP, despite their similar chemical structures.

  2. Elemental analysis of materials in an underwater archeological shipwreck using a novel remote laser-induced breakdown spectroscopy system.

    Science.gov (United States)

    Guirado, Salvador; Fortes, Francisco J; Laserna, J Javier

    2015-05-01

    LIBS analysis of submerged materials in an underwater archeological site has been performed for the first time. A fiber-optics-based remote instrument was designed for the recognition and identification of archeological assets in the wreck of the Bucentaure (Bay of Cadiz, South of Spain). The LIBS prototype featured both single-pulse (SP-LIBS) and multi-pulse excitation (MP-LIBS). The use of multi-pulse excitation allowed an increased laser beam energy (up to 95 mJ) transmitted through the optical fiber. This excitation mode results in an improved performance of the equipment in terms of extended range of analysis (to a depth of 50 m) and a broader variety of samples to be analyzed (i.e., rocks, marble, ceramics and concrete). Compared to single-pulse, an intensity enhancement factor of 15× was observed at the same irradiance value, 1.89 GW/cm(2). Thus, a longer pulse duration promotes the heating and melting of the sample, resulting in a greater mass ablated. As a consequence of the optimization of experimental conditions performed in laboratory, underwater characterization of ancient pottery was achieved.

  3. Time-resolved laser-induced breakdown spectroscopy of aluminum

    Institute of Scientific and Technical Information of China (English)

    LIU Xian-yun; ZHANG Wei-jun; WANG Zhen-ya; HAO Li-qing; HUANG Ming-qiang; ZHAO Wen-wu; LONG Bo; Zhao Wei

    2008-01-01

    We develop a system to measure the elemental composition of unprepared samples using laser-induced breakdown spectroscopy (LIBS) in our laboratory, which can be used for the determination of elements in solids, liquids and aerosols. A description of the instrumentation, including laser, sample chamber and detection, is followed by a brief discussion. The time-resolved LIBS of aluminum at atmospheric pressure is presented. At the end, the possibilities and later uses of this technique are briefly discussed.

  4. A nonlinearized multivariate dominant factor-based partial least squares (PLS) model for coal analysis by using laser-induced breakdown spectroscopy.

    Science.gov (United States)

    Feng, Jie; Wang, Zhe; Li, Lizhi; Li, Zheng; Ni, Weidou

    2013-03-01

    A nonlinearized multivariate dominant factor-based partial least-squares (PLS) model was applied to coal elemental concentration measurement. For C concentration determination in bituminous coal, the intensities of multiple characteristic lines of the main elements in coal were applied to construct a comprehensive dominant factor that would provide main concentration results. A secondary PLS thereafter applied would further correct the model results by using the entire spectral information. In the dominant factor extraction, nonlinear transformation of line intensities (based on physical mechanisms) was embedded in the linear PLS to describe nonlinear self-absorption and inter-element interference more effectively and accurately. According to the empirical expression of self-absorption and Taylor expansion, nonlinear transformations of atomic and ionic line intensities of C were utilized to model self-absorption. Then, the line intensities of other elements, O and N, were taken into account for inter-element interference, considering the possible recombination of C with O and N particles. The specialty of coal analysis by using laser-induced breakdown spectroscopy (LIBS) was also discussed and considered in the multivariate dominant factor construction. The proposed model achieved a much better prediction performance than conventional PLS. Compared with our previous, already improved dominant factor-based PLS model, the present PLS model obtained the same calibration quality while decreasing the root mean square error of prediction (RMSEP) from 4.47 to 3.77%. Furthermore, with the leave-one-out cross-validation and L-curve methods, which avoid the overfitting issue in determining the number of principal components instead of minimum RMSEP criteria, the present PLS model also showed better performance for different splits of calibration and prediction samples, proving the robustness of the present PLS model.

  5. Archaeological applications of laser-induced breakdown spectroscopy: an example from the Coso Volcanic Field, California, using advanced statistical signal processing analysis

    Energy Technology Data Exchange (ETDEWEB)

    Remus, Jeremiah J.; Gottfried, Jennifer L.; Harmon, Russell S.; Draucker, Anne; Baron, Dirk; Yohe, Robert

    2010-05-01

    Over the past quarter century, multielement chemical analysis has become a common means for attributing the provenance of archaeological materials. The Coso Volcanic Field (CVF) in California, USA, contains at least 38 high-silica rhyolite domes, many of which contain obsidian glass that has been quarried for tools by the indigenous population for more than 12,000 years. Artifacts made from CVF obsidian are found throughout the southwestern United States and geochemical sourcing of CVF obsidian has been an important tool in understanding prehistoric Native American trading patterns. Laser-induced breakdown spectroscopy (LIBS) is a simple atomic emission spectroscopic technique that has the potential for real-time man-portable chemical analysis in the field. Because LIBS is simultaneously sensitive to all elements, a single laser shot can be used to record the broadband emission spectra, which provides a ''chemical fingerprint'' of a material. Single-shot broadband LIBS spectra were collected using a commercial benchtop LIBS system for 27 obsidian samples from major sites across the CVF and four additional sites in California and western Nevada outside of CVF. Classification of the samples was performed using partial least-squares discriminant analysis (PLSDA), a common chemometric technique suitable for performing regression on high-dimensional data. Provenance identification for the obsidian samples was evaluated for three separate labeling frameworks. The first framework consisted of a binary classification problem to distinguish CVF samples from non-CVF samples. The second approach focused on the CVF samples with labels that corresponded to the eight separate Coso sites encompassed by the 27 samples. In the third analysis, non-CVF samples were excluded, and the remaining 27 CVF samples were labeled based on groupings defined from previous major and trace element chemical studies, which reduces the number of possible classes from eight to four

  6. Effects of laser focusing and fluence on the analysis of pellets of plant materials by laser-induced breakdown spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Gustinelli Arantes de Carvalho, Gabriel [Centro de Energia Nuclear na Agricultura, Universidade de Sao Paulo, Av. Centenario 303, 13416-000 Piracicaba, SP (Brazil); Santos, Dario [Universidade Federal de Sao Paulo - UNIFESP, Campus Diadema, Rua Prof. Artur Riedel 275, 09972-270 Diadema, SP (Brazil); Nunes, Lidiane Cristina [Centro de Energia Nuclear na Agricultura, Universidade de Sao Paulo, Av. Centenario 303, 13416-000 Piracicaba, SP (Brazil); Gomes, Marcos da Silva [Departamento de Quimica, Universidade Federal de Sao Carlos, Rod. Washington Luis, km 235, 13565-905 Sao Carlos, SP (Brazil); Leme, Flavio de Oliveira [Centro de Energia Nuclear na Agricultura, Universidade de Sao Paulo, Av. Centenario 303, 13416-000 Piracicaba, SP (Brazil); Krug, Francisco Jose, E-mail: fjkrug@cena.usp.br [Centro de Energia Nuclear na Agricultura, Universidade de Sao Paulo, Av. Centenario 303, 13416-000 Piracicaba, SP (Brazil)

    2012-08-15

    The effects of laser focusing and fluence on LIBS analysis of pellets of plant leaves was evaluated. A Q-switched Nd:YAG laser (5 ns, 10 Hz, 1064 nm) was used and the emission signals were collected by lenses into an optical fiber coupled to a spectrometer with Echelle optics and ICCD. Data were acquired from the accumulation of 20 laser pulses at 2.0 {mu}s delay and 5.0 {mu}s integration time gate. The emission signal intensities increased with both laser fluence and spot size. Higher sensitivities for Ca, K, Mg, P, Al, B, Cu, Fe, Mn, and Zn determinations were observed for fluences in the range from 25 to 60 J cm{sup -2}. Coefficients of variation of site-to-site measurements were generally lower than 10% (n = 30 sites, 20 laser pulses/site) for a fluence of 50 J cm{sup -2} and 750 {mu}m spot size. For most elements, there is an indication that accuracy is improved with higher fluences. - Highlights: Black-Right-Pointing-Pointer Laser focusing and fluence affect the quality of LIBS results. Black-Right-Pointing-Pointer Improvements on sensitivity and precision were observed for most analytes. Black-Right-Pointing-Pointer Matrix effects can be minimized by choosing the most appropriate fluence.

  7. Elemental and molecular analysis of metal containing biomolecules using laser induced breakdown spectroscopy and sonic spray ionization mass spectrometry: A step towards full integration and simultaneous analysis

    Science.gov (United States)

    Marmatakis, Konstantinos; Pergantis, Spiros A.; Anglos, Demetrios

    2016-12-01

    A novel methodology is proposed that combines sonic spray ionization (SSI) mass spectrometry (MS) with laser induced breakdown spectroscopy (LIBS) for analyzing metal-containing biomolecules and complexes. Focusing pulses from a nanosecond laser (Nd:YAG, λ = 1064 nm) in the microdroplet ensemble produced by a pneumatic nebulizer yielded LIBS spectra that enabled highly sensitive detection of several metal ions in aqueous and aqueous methanolic solutions. Based on the calibration curve method, LOD values at the ng/mL level were achieved for Ca (15 ng/mL), Ba (27 ng/mL), Cu (67 ng/mL) and Fe (650 ng/mL) with accuracy > 90%. LIBS measurements were performed for the first time on aerosols of solutions of known biomolecules such as superoxide dismutase and alpha-lactalbumin, which led to the reliable determination of the concentration of Cu and Ca, respectively, both in the range of a few μg/mL. In parallel, the relative molecular mass of the metalloproteins was determined by separate SSI-MS measurements performed using an identical pneumatic nebulizer based sample introduction system. This is a first step towards the ultimate aim of integrating the two analytical techniques by use of a single pneumatic nebulization system for simultaneous sample introduction for both LIBS and SSI-MS. Such a system is expected to greatly enhance our capabilities to simultaneously acquire molecular and atomic data.

  8. Characterization of laser ablation of copper in the irradiance regime of laser-induced breakdown spectroscopy analysis

    Energy Technology Data Exchange (ETDEWEB)

    Picard, J., E-mail: jessica.picard@cea.fr [Commissariat à l' Energie Atomique, DAM, Valduc, F-21120 Is-sur-Tille (France); Sirven, J.-B.; Lacour, J.-L. [Commissariat à l' Energie Atomique, DEN/DANS/DPC/SEARS/LANIE, Saclay, F-91191 Gif-sur-Yvette (France); Musset, O. [Université de Bourgogne, Laboratoire Interdisciplinaire Carnot de Bourgogne, UMR CNRS 5209, F-21000 Dijon (France); Cardona, D.; Hubinois, J.-C. [Commissariat à l' Energie Atomique, DAM, Valduc, F-21120 Is-sur-Tille (France); Mauchien, P. [Commissariat à l' Energie Atomique, DEN/DANS/DPC/SEARS/LANIE, Saclay, F-91191 Gif-sur-Yvette (France)

    2014-11-01

    The LIBS signal depends both on the ablated mass and on the plasma excitation temperature. These fundamental parameters depend in a complex manner on laser ablation and on laser–plasma coupling. As several works in the literature suggest that laser ablation processes play a predominant role compared to plasma heating phenomena in the LIBS signal variations, this paper focuses on the study of laser ablation. The objective was to determine an interaction regime enabling to maximally control the laser ablation. Nanosecond laser ablation of copper at 266 nm was characterized by scanning electron microscopy and optical profilometry analysis, in air at 1 bar and in the vacuum. The laser beam spatial profile at the sample surface was characterized in order to give realistic values of the irradiance. The effect of the number of accumulated laser shots on the crater volume was studied. Then, the ablation crater morphology, volume, depth and diameter were measured as a function of irradiance between 0.35 and 96 GW/cm². Results show that in the vacuum, a regular trend is observed over the whole irradiance range. In air at 1 bar, below a certain irradiance, laser ablation is very similar to the vacuum case, and the ablation efficiency of copper was estimated at 0.15 ± 0.03 atom/photon. Beyond this irradiance, the laser beam propagation is strongly disrupted by the expansion of the dense plasma, and plasma shielding appears. The fraction of laser energy used for laser ablation and for plasma heating is estimated in the different irradiance regimes. - Highlights: • The morphology of copper's craters was studied as a function of the pulse energy. • Correlation at low energy and two pressures between crater volume and pulse energy • The ablation efficiency of copper at 1 bar is equal to 0.15 atom/photon. • Ablation efficiency in the vacuum is not limited by laser–plasma interaction. • Physical mechanisms of laser ablation at both pressures are discussed.

  9. Unsupervised verification of laser-induced breakdown spectroscopy dataset clustering

    Science.gov (United States)

    Wójcik, Michał R.; Zdunek, Rafał; Antończak, Arkadiusz J.

    2016-12-01

    Laser-induced breakdown spectroscopy is a versatile, optical technique used in a wide range of qualitative and quantitative analyses conducted with the use of various chemometric techniques. The aim of this research is to demonstrate the possibility of unsupervised clustering of an unknown dataset using K-means clustering algorithm, and verifying its input parameters through investigating generalized eigenvalues derived with linear discriminant analysis. In all the cases, principal component analyses have been applied to reduce data dimensionality and shorten computation time of the whole operation. The experiment was conducted on a dataset collected from twenty four different materials divided into six groups: metals, semiconductors, ceramics, rocks, metal alloys and others with the use of a three-channel spectrometer (298.02-628.73nm overall spectral range) and a UV (248nm) excimer laser. Additionally, two more complex groups containing all specimens and all specimens excluding rocks were created. The resulting spaces of eigenvalues were calculated for every group and three different distances in the multidimensional space (cosine, square Euclidean and L1). As expected, the correct numbers of specimens within groups with small deviations were obtained, and the validity of the unsupervised method has thus been proven.

  10. A novel strategy for preparing calibration standards for the analysis of plant materials by laser-induced breakdown spectroscopy: A case study with pellets of sugar cane leaves

    Energy Technology Data Exchange (ETDEWEB)

    Silva Gomes, Marcos da [Universidade de São Paulo, Centro de Energia Nuclear na Agricultura (CENA), Laboratório de Química Analítica, Caixa Postal 96, CEP 13416-000, Piracicaba, SP (Brazil); Universidade Federal de São Carlos, Departamento de Química, Rodovia Washington Luiz km 235, São Carlos, SP (Brazil); Gustinelli Arantes de Carvalho, Gabriel [Universidade de São Paulo, Centro de Energia Nuclear na Agricultura (CENA), Laboratório de Química Analítica, Caixa Postal 96, CEP 13416-000, Piracicaba, SP (Brazil); Santos, Dário [Universidade Federal de São Paulo, Departamento de Ciências Exatas e da Terra, Rua Professor Arthur Riedel 275, Diadema, SP (Brazil); Krug, Francisco José, E-mail: fjkrug@cena.usp.br [Universidade de São Paulo, Centro de Energia Nuclear na Agricultura (CENA), Laboratório de Química Analítica, Caixa Postal 96, CEP 13416-000, Piracicaba, SP (Brazil)

    2013-08-01

    Calibration is still a challenging task when dealing with the direct analysis of solids. This is particularly true for laser-induced breakdown spectroscopy (LIBS), and laser ablation inductively coupled plasma optical emission spectrometry/mass spectrometry, when the calibrations are matrix-dependent and/or appropriate certified reference materials are generally not available. Looking at the analysis of plant materials in the form of pressed pellets by LIBS, a new method to overcome and/or minimize this difficulty is proposed by keeping the matrix constant in order to produce matrix-matched calibration pellets. To achieve this goal and to test this novel approach, ground sugar cane leaves were chosen and submitted to acid extractions for obtaining the corresponding blank or a material containing very low concentrations of the analytes. The resulting dried solid material was used either as a blank or a low concentration standard, and also homogeneously mixed with the original plant material at appropriate ratios as well. The corresponding pellets were used as calibration standards and ablated at 30 different sites by applying 25 laser pulses per site with a Q-switched Nd:YAG at 1064 nm. The plasma emission collected by lenses was directed through an optical fiber towards a spectrometer equipped with Echelle optics and intensified charge-coupled device. Delay time and integration time gate were fixed at 2.0 and 5.0 μs, respectively. This calibration strategy was tested for the determination of Ca, Mg, K, P, Cu, Mn, and Zn by LIBS in pellets of leaves from 17 varieties of sugar cane and good correlations were obtained with inductively coupled plasma optical emission spectrometry results in the corresponding acid digests. The proposed approach was also useful to estimate the limits of detection based on measurements of blanks, as recommended by IUPAC, or with the aid of a low concentration standard. - Highlights: • Blanks and/or low concentration standards of plant

  11. Investigation of laser-induced breakdown spectroscopy and multivariate analysis for differentiating inorganic and organic C in a variety of soils

    Energy Technology Data Exchange (ETDEWEB)

    Martin, Madhavi Z., E-mail: martinm1@ornl.gov [BioSciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Mayes, Melanie A. [Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Climate Change Science Institute, Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Heal, Katherine R. [Department of Oceanography, University of Washington, Seattle, WA 98122 (United States); Brice, Deanne J. [Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Wullschleger, Stan D. [Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Climate Change Science Institute, Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States)

    2013-09-01

    Laser-induced breakdown spectroscopy (LIBS) along with multivariate analysis was used to differentiate between the total carbon (C), inorganic C, and organic C in a set of 58 different soils from 5 soil orders. A 532 nm laser with 45 mJ of laser power was used to excite the 58 samples of soil and the emission of all the elements present in the soil samples was recorded in a single spectrum with a wide wavelength range of 200–800 nm. The results were compared to the laboratory standard technique, e.g., combustion on a LECO-CN analyzer, to determine the true values for total C, inorganic C, and organic C concentrations. Our objectives were: 1) to determine the characteristic spectra of soils containing different amounts of organic and inorganic C, and 2) to examine the viability of this technique for differentiating between soils that contain predominantly organic and/or inorganic C content for a range of diverse soils. Previous work has shown that LIBS is an accurate and reliable approach to measuring total carbon content of soils, but it remains uncertain whether inorganic and organic forms of carbon can be separated using this approach. Total C and inorganic C exhibited correlation with rock-forming elements such as Al, Si, Fe, Ti, Ca, and Sr, while organic C exhibited minor correlation with these elements and a major correlation with Mg. We calculated a figure of merit (Mg/Ca) based on our results to enable differentiation between inorganic versus organic C. We obtained the LIBS validation prediction for total, inorganic, and organic C to have a coefficient of regression, r{sup 2} = 0.91, 0.87, and 0.91 respectively. These examples demonstrate an advance in LIBS-based techniques to distinguish between organic and inorganic C using the full wavelength spectra. - Highlights: • This research has successfully identified the organic and inorganic carbon in soil. • Multivariate analysis was used to show success in building a statistical model. • Can be used to

  12. A model combining spectrum standardization and dominant factor based partial least square method for carbon analysis in coal by laser-induced breakdown spectroscopy

    CERN Document Server

    Li, Xiongwei; Fu, Yangting; Li, Zheng; Ni, Weidou

    2014-01-01

    Successful quantitative measurement of carbon content in coal using laser-induced breakdown spectroscopy (LIBS) is suffered from relatively low precision and accuracy. In the present work, the spectrum standardization method was combined with the dominant factor based partial least square (PLS) method to improve the measurement accuracy of carbon content in coal by LIBS. The combination model employed the spectrum standardization method to convert the carbon line intensity into standard state for more accurately calculating the dominant carbon concentration, and then applied PLS with full spectrum information to correct the residual errors. The combination model was applied to the measurement of carbon content for 24 bituminous coal samples. The results demonstrated that the combination model could further improve the measurement accuracy compared with both our previously established spectrum standardization model and dominant factor based PLS model using spectral area normalized intensity for the dominant fa...

  13. Dispersive liquid-liquid microextraction for metals enrichment: a useful strategy for improving sensitivity of laser-induced breakdown spectroscopy in liquid samples analysis.

    Science.gov (United States)

    Aguirre, M A; Selva, E J; Hidalgo, M; Canals, A

    2015-01-01

    A rapid and efficient Dispersive Liquid-Liquid Microextraction (DLLME) followed by Laser-Induced Breakdown Spectroscopy detection (LIBS) was evaluated for simultaneous determination of Cr, Cu, Mn, Ni and Zn in water samples. Metals in the samples were extracted with tetrachloromethane as pyrrolidinedithiocarbamate (APDC) complexes, using vortex agitation to achieve dispersion of the extractant solvent. Several DLLME experimental factors affecting extraction efficiency were optimized with a multivariate approach. Under optimum DLLME conditions, DLLME-LIBS method was found to be of about 4.0-5.5 times more sensitive than LIBS, achieving limits of detection of about 3.7-5.6 times lower. To assess accuracy of the proposed DLLME-LIBS procedure, a certified reference material of estuarine water was analyzed.

  14. Plasma temperature clamping in filamentation laser induced breakdown spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Harilal, Sivanandan S.; Yeak, J.; Phillips, Mark C.

    2015-10-19

    Ultrafast laser filament induced breakdown spectroscopy is a very promising method for remote material detection. We present characteristics of plasmas generated in a metal target by laser filaments in air. Our measurements show that the temperature of the ablation plasma is clamped along the filamentation channel due to intensity clamping in a filament. Nevertheless, significant changes in radiation intensity are noticeable, and this is essentially due to variation in the number density of emitting atoms. The present results also partly explains the reason for the occurrence of atomic plume during fs LIBS in air compared to long-pulse ns LIBS.

  15. Comparing predictive ability of Laser-Induced Breakdown Spectroscopy to Near Infrared Spectroscopy for soil texture and organic carbon determination

    DEFF Research Database (Denmark)

    Knadel, Maria; Peng, Yi; Gislum, René;

    and texture was tested and compared with near infrared spectroscopy (NIRS) technique and traditional laboratory analysis. Calibration models were developed on 50 topsoil samples. For all properties except silt, higher predictive ability of LIBS than NIRS models was obtained. Successful calibrations indicate......Soil organic carbon (SOC) and texture have a practical value for agronomy and the environment. Thus, alternative techniques to supplement or substitute for the expensive conventional analysis of soil are developed. Here the feasibility of laser-induced breakdown spectroscopy (LIBS) to determine SOC...

  16. Fs–ns double-pulse Laser Induced Breakdown Spectroscopy of copper-based-alloys: Generation and elemental analysis of nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Guarnaccio, A.; Parisi, G.P.; Mollica, D. [CNR-ISM, U.O.S. Tito Scalo, Zona Industriale, 85050 Tito Scalo, PZ (Italy); De Bonis, A. [CNR-ISM, U.O.S. Tito Scalo, Zona Industriale, 85050 Tito Scalo, PZ (Italy); Dipartimento di Scienze, Università degli Studi della Basilicata, Via dell' Ateneo Lucano 10, 85100 Potenza (Italy); Teghil, R. [Dipartimento di Scienze, Università degli Studi della Basilicata, Via dell' Ateneo Lucano 10, 85100 Potenza (Italy); Santagata, A. [CNR-ISM, U.O.S. Tito Scalo, Zona Industriale, 85050 Tito Scalo, PZ (Italy)

    2014-11-01

    Evolution of nanoparticles ejected during ultra-short (250 fs) laser ablation of certified copper alloys and relative calibration plots of a fs–ns double-pulse Laser Induced Breakdown Spectroscopy orthogonal configuration is presented. All work was performed in air at atmospheric pressure using certified copper-based-alloy samples irradiated by a fs laser beam and followed by a delayed perpendicular ns laser pulse. In order to evaluate possible compositional changes of the fs induced nanoparticles, it was necessary to consider, for all samples used, comparable features of the detected species. With this purpose the induced nanoparticles black-body-like emission evolution and their relative temperature decay have been studied. These data were exploited for defining the distance between the target surface and the successive ns laser beam to be used. The consequent calibration plots of minor constituents (i.e. Sn, Pb and Zn) of the certified copper-based-alloy samples have been reported by taking into account self-absorption effects. The resulting linear regression coefficients suggest that the method used, for monitoring and ruling the fs laser induced nanoparticles, could provide a valuable approach for establishing the occurrence of potential compositional changes of the detected species. All experimental data reveal that the fs laser induced nanoparticles can be used for providing a coherent composition of the starting target. In the meantime, the fs–ns double-pulse Laser Induced Breakdown Spectroscopy orthogonal configuration here used can be considered as an efficient technique for compositional determination of the nanoparticles ejected during ultra-short laser ablation processes. - Highlights: • Laser induced NP continuum black-body-like emission was used for T determination. • Invariable composition of generated NPs was assumed in the range of 20 μs. • Fs-ns DP-LIBS was employed for the compositional characterization of NPs. • NPs obtained by fs

  17. Comparison of laser induced breakdown spectroscopy and spark induced breakdown spectroscopy for determination of mercury in soils

    Energy Technology Data Exchange (ETDEWEB)

    Srungaram, Pavan K.; Ayyalasomayajula, Krishna K.; Yu-Yueh, Fang; Singh, Jagdish P., E-mail: singh@icet.msstate.edu

    2013-09-01

    Mercury is a toxic element found throughout the environment. Elevated concentrations of mercury in soils are quite hazardous to plants growing in these soils and also the runoff of soils to nearby water bodies contaminates the water, endangering the flora and fauna of that region. This makes continuous monitoring of mercury very essential. This work compares two potential spectroscopic methods (laser induced breakdown spectroscopy (LIBS) and spark induced breakdown spectroscopy (SIBS)) at their optimum experimental conditions for mercury monitoring. For LIBS, pellets were prepared from soil samples of known concentration for generating a calibration curve while for SIBS, soil samples of known concentration were used in the powder form. The limits of detection (LODs) of Hg in soil were calculated from the Hg calibration curves. The LOD for mercury in soil calculated using LIBS and SIBS is 483 ppm and 20 ppm, respectively. The detection range for LIBS and SIBS is discussed. - Highlights: • We compared SIBS and LIBS for mercury (Hg) measurements in soil. • Hg 546.07 nm line was selected for both LIBS and SIBS measurements. • Limit of detection for Hg was found to be 20 ppm with SIBS and 483 ppm with LIBS.

  18. In-Field, In Situ, and In Vivo 3-Dimensional Elemental Mapping for Plant Tissue and Soil Analysis Using Laser-Induced Breakdown Spectroscopy

    Directory of Open Access Journals (Sweden)

    Chunjiang Zhao

    2016-10-01

    Full Text Available Sensing and mapping element distributions in plant tissues and its growth environment has great significance for understanding the uptake, transport, and accumulation of nutrients and harmful elements in plants, as well as for understanding interactions between plants and the environment. In this study, we developed a 3-dimensional elemental mapping system based on laser-induced breakdown spectroscopy that can be deployed in- field to directly measure the distribution of multiple elements in living plants as well as in the soil. Mapping is performed by a fast scanning laser, which ablates a micro volume of a sample to form a plasma. The presence and concentration of specific elements are calculated using the atomic, ionic, and molecular spectral characteristics of the plasma emission spectra. Furthermore, we mapped the pesticide residues in maize leaves after spraying to demonstrate the capacity of this method for trace elemental mapping. We also used the system to quantitatively detect the element concentrations in soil, which can be used to further understand the element transport between plants and soil. We demonstrate that this method has great potential for elemental mapping in plant tissues and soil with the advantages of 3-dimensional and multi-elemental mapping, in situ and in vivo measurement, flexible use, and low cost.

  19. In-Field, In Situ, and In Vivo 3-Dimensional Elemental Mapping for Plant Tissue and Soil Analysis Using Laser-Induced Breakdown Spectroscopy.

    Science.gov (United States)

    Zhao, Chunjiang; Dong, Daming; Du, Xiaofan; Zheng, Wengang

    2016-10-22

    Sensing and mapping element distributions in plant tissues and its growth environment has great significance for understanding the uptake, transport, and accumulation of nutrients and harmful elements in plants, as well as for understanding interactions between plants and the environment. In this study, we developed a 3-dimensional elemental mapping system based on laser-induced breakdown spectroscopy that can be deployed in- field to directly measure the distribution of multiple elements in living plants as well as in the soil. Mapping is performed by a fast scanning laser, which ablates a micro volume of a sample to form a plasma. The presence and concentration of specific elements are calculated using the atomic, ionic, and molecular spectral characteristics of the plasma emission spectra. Furthermore, we mapped the pesticide residues in maize leaves after spraying to demonstrate the capacity of this method for trace elemental mapping. We also used the system to quantitatively detect the element concentrations in soil, which can be used to further understand the element transport between plants and soil. We demonstrate that this method has great potential for elemental mapping in plant tissues and soil with the advantages of 3-dimensional and multi-elemental mapping, in situ and in vivo measurement, flexible use, and low cost.

  20. Identification of inks and structural characterization of contemporary artistic prints by laser-induced breakdown spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Oujja, M. [Instituto de Quimica Fisica Rocasolano, CSIC, Serrano 119, 28006 Madrid (Spain); Vila, A. [Departament de Pintura, Conservacio-Restauracio, Facultat de Belles Arts, Universitat de Barcelona, Pau Gargallo 4, 08028 Barcelona (Spain); Rebollar, E. [Instituto de Quimica Fisica Rocasolano, CSIC, Serrano 119, 28006 Madrid (Spain); Garcia, J.F. [Departament de Pintura, Conservacio-Restauracio, Facultat de Belles Arts, Universitat de Barcelona, Pau Gargallo 4, 08028 Barcelona (Spain); Castillejo, M. [Instituto de Quimica Fisica Rocasolano, CSIC, Serrano 119, 28006 Madrid (Spain)]. E-mail: marta.castillejo@iqfr.csic.es

    2005-08-31

    Identification of the inks used in artistic prints and the order in which different ink layers have been applied on a paper substrate are important factors to complement the classical stylistic aspects for the authentication of this type of objects. Laser-induced breakdown spectroscopy (LIBS) is investigated to determine the chemical composition and structural distribution of the constituent materials of model prints made by applying one or two layers of several blue and black inks on an Arches paper substrate. By using suitable laser excitation conditions, identification of the inks was possible by virtue of emissions from key elements present in their composition. Analysis of successive spectra on the same spot allowed the identification of the order in which the inks were applied on the paper. The results show the potential of laser-induced breakdown spectroscopy for the chemical and structural characterization of artistic prints.

  1. Time resolved laser-induced breakdown spectroscopy for calcium concentration detection in water

    Institute of Scientific and Technical Information of China (English)

    WU Jiang-lai; LU Yuan; Li Ying; CHENG Kai; GUO Jin-jia; ZHENG Rong-er

    2011-01-01

    @@ The laser induced breakdown spectroscopy (LIBS) is an element analysis technique with the advantages of real time detection, simultaneous multi-element identification, and in-situ and stand-off capacities.To evaluate its potential of ocean applications, in this paper, the time resolved laser-induced breakdown spectroscopy for calcium concentration detection in water is investigated.With the optimum experimental parameters, the plasma emission lifetime is determined to be about 500 ns with 532 nm laser excitation, and 1000 ns with 1064 nm laser excitation.The lowest detection concentration of 50ppm is achieved for calcium detection in CaC12 water solution using the 532 nm LIBS.Even better detection sensitivity is achieved using the 1064 nm LIBS, and the resulted lowest detection concentration of calcium is 25 ppm.The results suggest that it is feasible to develop LIBS as an on-line sensor for metal element monitoring in the sea.

  2. Apparatus, system, and method for laser-induced breakdown spectroscopy

    Science.gov (United States)

    Effenberger, Jr., Andrew J; Scott, Jill R; McJunkin, Timothy R

    2014-11-18

    In laser-induced breakdown spectroscopy (LIBS), an apparatus includes a pulsed laser configured to generate a pulsed laser signal toward a sample, a constructive interference object and an optical element, each located in a path of light from the sample. The constructive interference object is configured to generate constructive interference patterns of the light. The optical element is configured to disperse the light. A LIBS system includes a first and a second optical element, and a data acquisition module. The data acquisition module is configured to determine an isotope measurement based, at least in part, on light received by an image sensor from the first and second optical elements. A method for performing LIBS includes generating a pulsed laser on a sample to generate light from a plasma, generating constructive interference patterns of the light, and dispersing the light into a plurality of wavelengths.

  3. Spectroscopy of laser-produced plasmas: Setting up of high-performance laser-induced breakdown spectroscopy system

    Indian Academy of Sciences (India)

    V K Unnikrishnan; Kamlesh Alti; Rajesh Nayak; Rodney Bernard; V B Kartha; C Santhosh; G P Gupta; B M Suri

    2010-12-01

    It is a well-known fact that laser-induced breakdown spectroscopy (LIBS) has emerged as one of the best analytical techniques for multi-elemental compositional analysis of samples. We report assembling and optimization of LIBS set up using high resolution and broad-range echelle spectrograph coupled to an intensified charge coupled device (ICCD) to detect and quantify trace elements in environmental and clinical samples. Effects of variations of experimental parameters on spectroscopy signals of copper and brass are reported. Preliminary results of some plasma diagnostic calculations using recorded time-resolved optical emission signals are also reported for brass samples.

  4. Optical-fiber-based laser-induced breakdown spectroscopy for detection of early caries

    Science.gov (United States)

    Sasazawa, Shuhei; Kakino, Satoko; Matsuura, Yuji

    2015-06-01

    A laser-induced breakdown spectroscopy (LIBS) system targeting for the in vivo analysis of tooth enamel is described. The system is planned to enable real-time analysis of teeth during laser dental treatment by utilizing a hollow optical fiber that transmits both Q-switched Nd:YAG laser light for LIBS and infrared Er:YAG laser light for tooth ablation. The sensitivity of caries detection was substantially improved by expanding the spectral region under analysis to ultraviolet (UV) light and by focusing on emission peaks of Zn in the UV region. Subsequently, early caries were distinguished from healthy teeth with accuracy rates above 80% in vitro.

  5. Quantitative laser-induced breakdown spectroscopy data using peak area step-wise regression analysis: an alternative method for interpretation of Mars science laboratory results

    Energy Technology Data Exchange (ETDEWEB)

    Clegg, Samuel M [Los Alamos National Laboratory; Barefield, James E [Los Alamos National Laboratory; Wiens, Roger C [Los Alamos National Laboratory; Dyar, Melinda D [MT HOLYOKE COLLEGE; Schafer, Martha W [LSU; Tucker, Jonathan M [MT HOLYOKE COLLEGE

    2008-01-01

    The ChemCam instrument on the Mars Science Laboratory (MSL) will include a laser-induced breakdown spectrometer (LIBS) to quantify major and minor elemental compositions. The traditional analytical chemistry approach to calibration curves for these data regresses a single diagnostic peak area against concentration for each element. This approach contrasts with a new multivariate method in which elemental concentrations are predicted by step-wise multiple regression analysis based on areas of a specific set of diagnostic peaks for each element. The method is tested on LIBS data from igneous and metamorphosed rocks. Between 4 and 13 partial regression coefficients are needed to describe each elemental abundance accurately (i.e., with a regression line of R{sup 2} > 0.9995 for the relationship between predicted and measured elemental concentration) for all major and minor elements studied. Validation plots suggest that the method is limited at present by the small data set, and will work best for prediction of concentration when a wide variety of compositions and rock types has been analyzed.

  6. Study of Bacterial Samples Using Laser Induced Breakdown Spectroscopy

    Science.gov (United States)

    W, A. Farooq; M, Atif; W, Tawfik; M, S. Alsalhi; Z, A. Alahmed; M, Sarfraz; J, P. Singh

    2014-12-01

    Laser-induced breakdown spectroscopy (LIBS) technique has been applied to investigate two different types of bacteria, Escherichia coli (B1) and Micrococcus luteus (B2) deposited on glass slides using Spectrolaser 7000. LIBS spectra were analyzed using spectrolaser software. LIBS spectrum of glass substrate was compared with bacteria spectra. Ca, Mg, Na, K, P, S, Cl, Fe, Al, Mn, Cu, C, H and CN-band appeared in bacterial samples in air. Two carbon lines at 193.02 nm, 247.88 nm and one hydrogen line at 656.28 nm with intensity ratios of 1.9, 1.83 and 1.53 appeared in bacterial samples B1 and B2 respectively. Carbon and hydrogen are the important components of the bio-samples like bacteria and other cancer cells. Investigation on LIBS spectra of the samples in He and Ar atmospheres is also presented. Ni lines appeared only in B2 sample in Ar atmosphere. From the present experimental results we are able to show that LIBS technique has a potential in the identification and discrimination of different types of bacteria.

  7. Laser induced breakdown spectroscopy with picosecond pulse train

    Science.gov (United States)

    Lednev, Vasily N.; Pershin, Sergey M.; Sdvizhenskii, Pavel A.; Grishin, Mikhail Ya; Davydov, Mikhail A.; Stavertiy, Anton Ya; Tretyakov, Roman S.

    2017-02-01

    Picosecond pulse train and nanosecond pulse were compared for laser ablation and laser induced breakdown spectroscopy (LIBS) measurements. A detailed study revealed that the picosecond pulse train ablation improved the quality of laser craters (symmetric crater walls and the absence of large redeposited droplets), which was explained by a smaller heat affected zone and suppression of melt splash. Greater plasma dimensions and brighter plasma emission were observed by gated imaging for picosecond pulse train compared to nanosecond pulse ablation. Increased intensity of atomic and ionic lines in gated and time integrated spectra provided better signal-to-noise ratio for picosecond pulse train sampling. Higher temperature and electron density were detected during first microsecond for the plasma induced by the picosecond pulse train. Improved shot-to-shot reproducibility for atomic/ionic line intensity in the case of picosecond pulse train LIBS was explained by more effective atomization of target material in plasma and better quality of laser craters. Improved precision and limits of detections were determined for picosecond pulse train LIBS due to better reproducibility of laser sampling and increased signal-to-noise ratio.

  8. Detection of Anomalies in Citrus Leaves Using Laser-Induced Breakdown Spectroscopy (LIBS).

    Science.gov (United States)

    Sankaran, Sindhuja; Ehsani, Reza; Morgan, Kelly T

    2015-08-01

    Nutrient assessment and management are important to maintain productivity in citrus orchards. In this study, laser-induced breakdown spectroscopy (LIBS) was applied for rapid and real-time detection of citrus anomalies. Laser-induced breakdown spectroscopy spectra were collected from citrus leaves with anomalies such as diseases (Huanglongbing, citrus canker) and nutrient deficiencies (iron, manganese, magnesium, zinc), and compared with those of healthy leaves. Baseline correction, wavelet multivariate denoising, and normalization techniques were applied to the LIBS spectra before analysis. After spectral pre-processing, features were extracted using principal component analysis and classified using two models, quadratic discriminant analysis and support vector machine (SVM). The SVM resulted in a high average classification accuracy of 97.5%, with high average canker classification accuracy (96.5%). LIBS peak analysis indicated that high intensities at 229.7, 247.9, 280.3, 393.5, 397.0, and 769.8 nm were observed of 11 peaks found in all the samples. Future studies using controlled experiments with variable nutrient applications are required for quantification of foliar nutrients by using LIBS-based sensing.

  9. Time-Resolved Spectroscopy Diagnostic of Laser-Induced Optical Breakdown

    Directory of Open Access Journals (Sweden)

    Christian G. Parigger

    2010-01-01

    Full Text Available Transient laser plasma is generated in laser-induced optical breakdown (LIOB. Here we report experiments conducted with 10.6-micron CO2 laser radiation, and with 1.064-micron fundamental, 0.532-micron frequency-doubled, 0.355-micron frequency-tripled Nd:YAG laser radiation. Characterization of laser induced plasma utilizes laser-induced breakdown spectroscopy (LIBS techniques. Atomic hydrogen Balmer series emissions show electron number density of 1017 cm−3 measured approximately 10 μs and 1 μs after optical breakdown for CO2 and Nd:YAG laser radiation, respectively. Recorded molecular recombination emission spectra of CN and C2 Swan bands indicate an equilibrium temperature in excess of 7000 Kelvin, inferred for these diatomic molecules. Reported are also graphite ablation experiments where we use unfocused laser radiation that is favorable for observation of neutral C3 emission due to reduced C3 cation formation. Our analysis is based on computation of diatomic molecular spectra that includes accurate determination of rotational line strengths, or Hönl-London factors.

  10. Characterization of hard coatings produced by laser cladding using laser-induced breakdown spectroscopy technique

    Energy Technology Data Exchange (ETDEWEB)

    Varela, J.A.; Amado, J.M.; Tobar, M.J.; Mateo, M.P.; Yañez, A.; Nicolas, G., E-mail: gines@udc.es

    2015-05-01

    Highlights: • Chemical mapping and profiling by laser-induced breakdown spectroscopy (LIBS) of coatings produced by laser cladding. • Production of laser clads using tungsten carbide (WC) and nickel based matrix (NiCrBSi) powders. • Calibration by LIBS of hardfacing alloys with different WC concentrations. - Abstract: Protective coatings with a high abrasive wear resistance can be obtained from powders by laser cladding technique, in order to extend the service life of some industrial components. In this work, laser clad layers of self-fluxing NiCrBSi alloy powder mixed with WC powder have been produced on stainless steel substrates of austenitic type (AISI 304) in a first step and then chemically characterized by laser-induced breakdown spectroscopy (LIBS) technique. With the suitable laser processing parameters (mainly output power, beam scan speed and flow rate) and powders mixture proportions between WC ceramics and NiCrBSi alloys, dense pore free layers have been obtained on single tracks and on large areas with overlapped tracks. The results achieved by LIBS technique and applied for the first time to the analysis of laser clads provided the chemical composition of the tungsten carbides in metal alloy matrix. Different measurement modes (multiple point analyses, depth profiles and chemical maps) have been employed, demonstrating the usefulness of LIBS technique for the characterization of laser clads based on hardfacing alloys. The behavior of hardness can be explained by LIBS maps which evidenced the partial dilution of some WC spheres in the coating.

  11. A Simple LIBS (Laser-Induced Breakdown Spectroscopy) Laboratory Experiment to Introduce Undergraduates to Calibration Functions and Atomic Spectroscopy

    Science.gov (United States)

    Chinni, Rosemarie C.

    2012-01-01

    This laboratory experiment introduces students to a different type of atomic spectroscopy: laser-induced breakdown spectroscopy (LIBS). LIBS uses a laser-generated spark to excite the sample; once excited, the elemental emission is spectrally resolved and detected. The students use LIBS to analyze a series of standard synthetic silicate samples…

  12. Nanoparticle detection in aqueous solutions using Raman and Laser Induced Breakdown Spectroscopy

    NARCIS (Netherlands)

    Sovago, M.; Buis, E.-J.; Sandtke, M.

    2013-01-01

    We show the chemical identification and quantification of the concentration and size of nanoparticle (NP) dispersions in aqueous solutions by using a combination of Raman Spectroscopy and Laser Induced Breakdown Spectroscopy (LIBS). The two spectroscopic techniques are applied to demonstrate the NP

  13. Laser Induced Breakdown Spectroscopy of meteorites as a probe of the early solar system

    Science.gov (United States)

    Dell'Aglio, M.; De Giacomo, A.; Gaudiuso, R.; De Pascale, O.; Longo, S.

    2014-11-01

    This paper presents an evaluation of Laser Induced Breakdown Spectroscopy (LIBS) as a technique for gathering data relevant to Solar System geophysics. Two test cases were demonstrated: elemental analysis of chondrules in a chondrite meteorite, and space- resolved analysis of the interface between kamacite and taenite crystals in an octahedrite iron meteorite. In particular most major and minor elements (Fe, Mg, Si, Ti, Al, Cr, Mn, Ca, Fe, Ni, Co) in Sahara 98222 (chondrite) and its chondrules, as well as the profile of Ni content in Toluca (iron meteorite), were determined with the Calibration Free (CF) method. A special attention was devoted to exploring the possibilities offered by variants of the basic technique, such as the use of Fe I Boltzmann distribution as an intensity calibration method of the spectroscopic system, and the use of spatially resolved analysis.

  14. Characteristics of solid aerosols produced by optical catapulting studied by laser-induced breakdown spectroscopy

    Science.gov (United States)

    Fortes, F. J.; Laserna, J. J.

    2010-08-01

    Optical catapulting (OC) constitutes an effective method to transport small amounts of different materials in the form of a solid aerosol. In this report, laser-induced breakdown spectroscopy (LIBS) is used for the analysis of those aerosols produced by OC. For this purpose, materials were catapulted using a Q-switch Nd:YAG laser. A second Q-switch Nd:YAG laser was used for LIBS analysis of the ejected particles. Data processing of aerosols was conducted using conditional data analysis. Also, the standard deviation method was used for the qualitative identification of the ejected particles. Two modes of interaction in OC (OC with focused or defocused pulses) have been evaluated and discussed. LIBS demonstrates that the distribution (spreading) of the ejected particles along the propagation axis increased as a function of the interpulse delay time. The mass density and the thickness of the target also play an important role in OC-LIBS.

  15. Comparing predictive ability of laser-induced breakdown spectroscopy to visible near-infrared spectroscopy for soil property determination

    DEFF Research Database (Denmark)

    Knadel, Maria; Gislum, René; Hermansen, Cecilie;

    2017-01-01

    for becoming an alternative method for soil analysis since it is faster and cheaper than conventional methods. Laser-induced breakdown spectroscopy (LIBS) is another cost-effective technique with potential for rapid analysis of elements present in the soil. In this study, the feasibility of using LIBS...... (p ¼ 0.0305) predictive ability for sand. Spiking improved the accuracy of most of the LIBS and viseNIRS models, indicating the importance of similarities between the calibration and the validation data sets. No significant differences (p > 0.05) were found between the LIBS and viseNIRS spiked...... country-scale models. Lower prediction errors for most properties were obtained using LIBS, rendering it an equally good or even a more accurate technique for soil properties determination than the well-established viseNIRS method....

  16. Laser ablation-laser induced breakdown spectroscopy for the measurement of total elemental concentration in soils.

    Science.gov (United States)

    Pareja, Jhon; López, Sebastian; Jaramillo, Daniel; Hahn, David W; Molina, Alejandro

    2013-04-10

    The performances of traditional laser-induced breakdown spectroscopy (LIBS) and laser ablation-LIBS (LA-LIBS) were compared by quantifying the total elemental concentration of potassium in highly heterogeneous solid samples, namely soils. Calibration curves for a set of fifteen samples with a wide range of potassium concentrations were generated. The LA-LIBS approach produced a superior linear response different than the traditional LIBS scheme. The analytical response of LA-LIBS was tested with a large set of different soil samples for the quantification of the total concentration of Fe, Mn, Mg, Ca, Na, and K. Results showed an acceptable linear response for Ca, Fe, Mg, and K while poor signal responses were found for Na and Mn. Signs of remaining matrix effects for the LA-LIBS approach in the case of soil analysis were found and discussed. Finally, some improvements and possibilities for future studies toward quantitative soil analysis with the LA-LIBS technique are suggested.

  17. Qualitative and quantitative laser-induced breakdown spectroscopy of bronze objects

    Science.gov (United States)

    Tankova, V.; Blagoev, K.; Grozeva, M.; Malcheva, G.; Penkova, P.

    2016-03-01

    Laser-induced breakdown spectroscopy (LIBS) is an analytical technique for qualitative and quantitative elemental analysis of solids, liquids and gases. In this work, the method was applied for investigation of archaeological bronze objects. The analytical information obtained by LIBS was used for qualitative determination of the elements in the material used for manufacturing of the objects under study. Quantitative chemical analysis was also performed after generating calibration curves with standard samples of similar matrix composition. Quantitative estimation of the elemental concentration of the bulk of the samples was performed, together with investigation of the surface layer of the objects. The results of the quantitative analyses gave indications about the manufacturing process of the investigated objects.

  18. Research progress in Asia on methods of processing laser-induced breakdown spectroscopy data

    Science.gov (United States)

    Guo, Yang-Min; Guo, Lian-Bo; Li, Jia-Ming; Liu, Hong-Di; Zhu, Zhi-Hao; Li, Xiang-You; Lu, Yong-Feng; Zeng, Xiao-Yan

    2016-10-01

    Laser-induced breakdown spectroscopy (LIBS) has attracted much attention in terms of both scientific research and industrial application. An important branch of LIBS research in Asia, the development of data processing methods for LIBS, is reviewed. First, the basic principle of LIBS and the characteristics of spectral data are briefly introduced. Next, two aspects of research on and problems with data processing methods are described: i) the basic principles of data preprocessing methods are elaborated in detail on the basis of the characteristics of spectral data; ii) the performance of data analysis methods in qualitative and quantitative analysis of LIBS is described. Finally, a direction for future development of data processing methods for LIBS is also proposed.

  19. Laser-induced breakdown spectroscopy detection of heavy metal in water based on graphite conch method

    Science.gov (United States)

    Wang, Chunlong; Liu, Jianguo; Zhao, Nanjing; Shi, Huan; Liu, Lituo; Ma, Mingjun; Zhang, Wei; Chen, Dong; Liu, Jing; Zhang, Yujun; Liu, Wenqing

    2012-10-01

    The laser-induced breakdown spectroscopy emission characteristics of trace heavy metal lead in water is studied based on graphite conch method, with a 1064nm wavelength Nd: YAG laser as excitation source, the echelle spectrometer and ICCD detector are used for spectral separation and high sensitive detection with high resolution and wide spectral range. The delay time 900ns and gate time 1600ns are determined in the experiment. The calibration curve of Pb is plotted based on the different concentration measurement results, and a limit of detection of 0.0138mg / L is obtained for Pb in water. Graphite conch method effectively overcomes the current problems on laser-induced breakdown spectroscopy detection of heavy metal in water. The detection limits and stability are improved. The reference data is provided for further study on the fast measurement of trace heavy metals in water by laser induced breakdown spectroscopy technique.

  20. Preliminary correlations of feature strength in spark-induced breakdown spectroscopy of bioaerosols with concentrations measured in laboratory analyses

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, Morgan S.; Bauer, Amy J. Ray

    2010-05-01

    We present preliminary results that show good correlation between elemental compositions of three bioaerosol samples, as measured in the laboratory by combustion analysis and with proton-induced x-ray emission and spark-induced breakdown spectroscopy signals integrated over the entire emission time profiles. Atomic (Ca, Al, Fe, and Si) and molecular features (CN, N2{sup +}, and OH) were observed compared to the laboratory data.

  1. Detection of Minerals in Green Leafy Vegetables Using Laser Induced Breakdown Spectroscopy

    Science.gov (United States)

    Shukla, P.; Kumar, R.; Raib, A. Kumar

    2016-11-01

    The distribution of minerals in different green leafy vegetables, such as spinach, chenopodium, chickpea, mustard, and fenugreek, was calculated using laser induced breakdown spectroscopy (LIBS). LIBS can provide an easy, reliable, efficient, low-cost, and in situ chemical analysis with a reasonable precision. In situ LIBS spectra in the range 200-500 nm were carried out using fresh leaves and leaves in the pellet form. As the spectra suggest, magnesium and calcium are present in each vegetable; however, the amount of them varies. It is observed that the amount of iron is maximal in spinach. The nutrition value of the plants was analyzed, and it was revealed that they are low in calories and fat and high in protein, fiber, iron, calcium, and phytochemicals.

  2. Determination of whey adulteration in milk powder by using laser induced breakdown spectroscopy.

    Science.gov (United States)

    Bilge, Gonca; Sezer, Banu; Eseller, Kemal Efe; Berberoglu, Halil; Topcu, Ali; Boyaci, Ismail Hakki

    2016-12-01

    A rapid and in situ method has been developed to detect and quantify adulterated milk powder through adding whey powder by using laser induced breakdown spectroscopy (LIBS). The methodology is based on elemental composition differences between milk and whey products. Milk powder, sweet and acid whey powders were produced as standard samples, and milk powder was adulterated with whey powders. Based on LIBS spectra of standard samples and commercial products, species was identified using principle component analysis (PCA) method, and discrimination rate of milk and whey powders was found as 80.5%. Calibration curves were obtained with partial least squares regression (PLS). Correlation coefficient (R(2)) and limit of detection (LOD) values were 0.981 and 1.55% for adulteration with sweet whey powder, and 0.985 and 0.55% for adulteration with acid whey powder, respectively. The results were found to be consistent with the data from inductively coupled plasma - mass spectrometer (ICP-MS) method.

  3. Use of laser induced breakdown spectroscopy in the determination of gem provenance: beryls.

    Science.gov (United States)

    McManus, Catherine E; McMillan, Nancy J; Harmon, Russell S; Whitmore, Robert C; De Lucia, Frank C; Miziolek, Andrzej W

    2008-11-01

    The provenance of gem stones has been of interest to geologists, gemologists, archeologists, and historians for centuries. Laser induced breakdown spectroscopy (LIBS) provides a minimally destructive tool for recording the rich chemical signatures of gem beryls (aquamarine, goshenite, heliodor, and morganite). Broadband LIBS spectra of 39 beryl (Be(3)Al(2)Si(6)O(18)) specimens from 11 pegmatite mines in New Hampshire, Connecticut, and Maine (USA) are used to assess the potential of using principal component analysis of LIBS spectra to determine specimen provenance. Using this technique, beryls from the three beryl-bearing zones in the Palermo #1 pegmatite (New Hampshire) can be recognized. However, the compositional variation within this single mine is comparable to that in beryls from all three states. Thus, a very large database with detailed location metadata will be required to routinely determine gem beryl provenance.

  4. Measurement of nutrients in green house soil with laser induced breakdown spectroscopy.

    Science.gov (United States)

    Hussain, T; Gondal, M A; Yamani, Z H; Baig, M A

    2007-01-01

    Laser-induced breakdown spectroscopy (LIBS) has been applied for the determination of nutrients in the green house soil samples. We determined appropriate spectral signatures of vital nutrients and calibrated the method to measure the nutrients in a naturally fertilized plot, cultivated with tomato and cucumber plants. From the calibration curves we predicted the concentrations of important nutrients such as Ca, K, P, Mg, Fe, S, Ni and Ba in the soil. Our measurements proved that the LIBS method rapidly and efficiently measures soil nutrients with excellent detection limits of 12, 9, 7, 9, 7, 10, 8 and 12 mg/kg for Ca, K, P, Mg, Fe, S, Ni and Ba respectively with a precision of approximately 2%, The unique features of LIBS for rapid sample analysis demonstrated by this study suggests that this method offers promise for precision measurements of soil nutrients as compared to conventional methods in short span of time.

  5. 3D Imaging of Nanoparticle Distribution in Biological Tissue by Laser-Induced Breakdown Spectroscopy

    Science.gov (United States)

    Gimenez, Y.; Busser, B.; Trichard, F.; Kulesza, A.; Laurent, J. M.; Zaun, V.; Lux, F.; Benoit, J. M.; Panczer, G.; Dugourd, P.; Tillement, O.; Pelascini, F.; Sancey, L.; Motto-Ros, V.

    2016-07-01

    Nanomaterials represent a rapidly expanding area of research with huge potential for future medical applications. Nanotechnology indeed promises to revolutionize diagnostics, drug delivery, gene therapy, and many other areas of research. For any biological investigation involving nanomaterials, it is crucial to study the behavior of such nano-objects within tissues to evaluate both their efficacy and their toxicity. Here, we provide the first account of 3D label-free nanoparticle imaging at the entire-organ scale. The technology used is known as laser-induced breakdown spectroscopy (LIBS) and possesses several advantages such as speed of operation, ease of use and full compatibility with optical microscopy. We then used two different but complementary approaches to achieve 3D elemental imaging with LIBS: a volume reconstruction of a sliced organ and in-depth analysis. This proof-of-concept study demonstrates the quantitative imaging of both endogenous and exogenous elements within entire organs and paves the way for innumerable applications.

  6. Detection and evaluation of uranium in different minerals by gamma spectrometry and laser induced breakdown spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Sergani, F.M.; Khedr, M.A.; Harith, M.A. [National Inst. of Laser Enhanced Sciences (NILES), Cairo Univ. (Egypt); El Mongy, S.A. [National Center for Nuclear Safety, Atomic Energy Authority, Nasr City, Cairo (Egypt)

    2004-07-01

    Analysis, detection and evaluation of source nuclear materials (e.g. uranium) in different minerals by sensitive techniques are a vital objective for uranium exploration, nuclear materials extraction, processing and verification. In this work, uranium in different geological formations was determined using gamma spectrometry and laser induced breakdown spectroscopy (LIBS). The investigated samples were collected from different regions distributed all over Egypt. The samples were then prepared for non-destructive analysis. A hyper pure germanium detector was used to measure the emitted gamma rays of uranium and its daughters in the samples. The concentrations of uranium in ppm ({mu}g/g) in the investigated samples are given and discussed in this work. The highest uranium concentration (4354.9 ppm) was found in uranophane samples of Gattar rocks. In Laser induced breakdown spectroscopy (LIBS) technique, plasma was formed by irradiating the rock surface with focused Q-switched Nd:Yag laser pulses of 7 ns pulse duration at the fundamental wavelength (1064 nm). Atoms and ions originating from the rock surface are excited and ionized in the laser produced hot plasma ({proportional_to}10 000 K). The plasma emission spectral line is characteristic of the elements present in the plasma and allows identification of the uranium in the uranophane mineral. The strong atomic line at 424.2 nm is used for the qualitative identification of uranium. It can be mentioned that the elevated levels of uranium in some of the investigated uranophane samples are of great economic feasibility to be extracted. (orig.)

  7. Preliminary design of laser-induced breakdown spectroscopy for proto-Material Plasma Exposure eXperiment.

    Science.gov (United States)

    Shaw, G; Martin, M Z; Martin, R; Biewer, T M

    2014-11-01

    Laser-induced breakdown spectroscopy (LIBS) is a technique for measuring surface matter composition. LIBS is performed by focusing laser radiation onto a target surface, ablating the surface, forming a plasma, and analyzing the light produced. LIBS surface analysis is a possible diagnostic for characterizing plasma-facing materials in ITER. Oak Ridge National Laboratory has enabled the initial installation of a laser-induced breakdown spectroscopy diagnostic on the prototype Material-Plasma Exposure eXperiment (Proto-MPEX), which strives to mimic the conditions found at the surface of the ITER divertor. This paper will discuss the LIBS implementation on Proto-MPEX, preliminary design of the fiber optic LIBS collection probe, and the expected results.

  8. Elemental analysis of coal by tandem laser induced breakdown spectroscopy and laser ablation inductively coupled plasma time of flight mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Dong, Meirong [School of Electric Power, South China University of Technology, Guangzhou, Guangdong 510640 (China); Lawrence Berkeley National Laboratory, University of California, Berkeley, CA 94720 (United States); Oropeza, Dayana [Lawrence Berkeley National Laboratory, University of California, Berkeley, CA 94720 (United States); Chirinos, José [Lawrence Berkeley National Laboratory, University of California, Berkeley, CA 94720 (United States); Escuela de Química, Facultad de Ciencias, Universidad Central de Venezuela, Caracas 1041a (Venezuela, Bolivarian Republic of); González, Jhanis J. [Lawrence Berkeley National Laboratory, University of California, Berkeley, CA 94720 (United States); Lu, Jidong [School of Electric Power, South China University of Technology, Guangzhou, Guangdong 510640 (China); Mao, Xianglei [Lawrence Berkeley National Laboratory, University of California, Berkeley, CA 94720 (United States); Russo, Richard E., E-mail: RERusso@lbl.gov [Lawrence Berkeley National Laboratory, University of California, Berkeley, CA 94720 (United States)

    2015-07-01

    The capabilities and analytical benefits of combined LIBS and LA-ICP-MS were evaluated for the analysis of coal samples. The ablation system consisted of a Nd:YAG laser operated 213 nm. A Czerny-turner spectrograph with ICCD detector and time-of-flight based mass spectrometer were utilized for LIBS and ICP-MS detection, respectively. This tandem approach allows simultaneous determination of major and minor elements (C, Si, Ca, Al, Mg), and trace elements (V, Ba, Pb, U, etc.) in the coal samples. The research focused on calibration strategies, specifically the use of univariate and multivariate data analysis on analytical performance. Partial least square regression (PLSR) was shown to minimize and compensate for matrix effects in the emission and mass spectra improving quantitative analysis by LIBS and LA-ICP-MS, respectively. The correlation between measurements from these two techniques demonstrated that mass spectral data combined with LIBS emission measurements by PLSR improved the accuracy and precision for quantitative analysis of trace elements in coal. - Highlights: • Tandem LIBS LA-ICP-MS • Simultaneous determination of major and minor elements and trace elements in the coal samples. • Extended Dynamic Range • Correlation between LIBS with LA-ICP-MS demonstrated improved the accuracy and precision for quantitative analysis of coal.

  9. Elemental analysis of coal by tandem laser induced breakdown spectroscopy and laser ablation inductively coupled plasma time of flight mass spectrometry

    Science.gov (United States)

    Dong, Meirong; Oropeza, Dayana; Chirinos, José; González, Jhanis J.; Lu, Jidong; Mao, Xianglei; Russo, Richard E.

    2015-07-01

    The capabilities and analytical benefits of combined LIBS and LA-ICP-MS were evaluated for the analysis of coal samples. The ablation system consisted of a Nd:YAG laser operated 213 nm. A Czerny-turner spectrograph with ICCD detector and time-of-flight based mass spectrometer were utilized for LIBS and ICP-MS detection, respectively. This tandem approach allows simultaneous determination of major and minor elements (C, Si, Ca, Al, Mg), and trace elements (V, Ba, Pb, U, etc.) in the coal samples. The research focused on calibration strategies, specifically the use of univariate and multivariate data analysis on analytical performance. Partial least square regression (PLSR) was shown to minimize and compensate for matrix effects in the emission and mass spectra improving quantitative analysis by LIBS and LA-ICP-MS, respectively. The correlation between measurements from these two techniques demonstrated that mass spectral data combined with LIBS emission measurements by PLSR improved the accuracy and precision for quantitative analysis of trace elements in coal.

  10. Quantifying lycopene synthesis and chlorophyll breakdown in tomato fruit using remittance VIS spectroscopy

    NARCIS (Netherlands)

    Schouten, R.E.; Farneti, B.; Tijskens, L.M.M.; Algarra Alarcon, A.; Woltering, E.J.

    2014-01-01

    The aim of this study was to increase the understanding of chlorophyll breakdown and lycopene synthesis at a quantitative level in Solanum lycopersicum fruit. To accomplish this, a kinetic model is proposed describing the transition from chloro- to chromoplast. Remittance VIS spectroscopy was used t

  11. Laser Induced Breakdown Spectroscopy in archeometry: A review of its application and future perspectives

    Energy Technology Data Exchange (ETDEWEB)

    Spizzichino, Valeria, E-mail: valeria.spizzichino@enea.it; Fantoni, Roberta

    2014-09-01

    Laser Induced Breakdown Spectroscopy (LIBS) in the last decades has been more and more applied to the field of Cultural Heritage with great results obtained either alone or in combination with complementary laser techniques. Its ability to analyze, with a minimal loss, different kinds of materials in laboratory, in situ and even in hostile environments has been highly appreciated. The main aim of this paper is to present a review of LIBS applications in the interdisciplinary field of archeometry. The LIBS technique is shortly described both from a theoretical and practical point of view, discussing the instrumental setup, also in comparison with typical features of laser induced fluorescence (LIF) and Raman spectroscopy apparata. The complementary with multivariate analysis, a method that can help in reducing data set dimensions and in pulling out effective information, is stressed. In particular the role of LIBS in Cultural Heritage material characterization, recognition of fakes and indirect dating is described, reporting general considerations and case studies on metal alloys, mural paintings, decorated ceramics, glasses, stones and gems. - Highlights: • Applications of LIBS to archeometry are reviewed. • Complementary among LIBS, LIF, Raman and multivariate analysis is highlighted. • Three major areas of successful LIBS application in archeometry are identified. • Significant results have been presented for several different materials.

  12. Laser-induced breakdown spectroscopy measurements of uranium and thorium powders and uranium ore

    Energy Technology Data Exchange (ETDEWEB)

    Judge, Elizabeth J. [Chemistry Division, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Barefield, James E., E-mail: jbarefield@lanl.gov [Chemistry Division, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Berg, John M. [Manufacturing Engineering and Technology Division, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Clegg, Samuel M.; Havrilla, George J.; Montoya, Velma M.; Le, Loan A.; Lopez, Leon N. [Chemistry Division, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)

    2013-05-01

    Laser-induced breakdown spectroscopy (LIBS) was used to analyze depleted uranium and thorium oxide powders and uranium ore as a potential rapid in situ analysis technique in nuclear production facilities, environmental sampling, and in-field forensic applications. Material such as pressed pellets and metals, has been extensively studied using LIBS due to the high density of the material and more stable laser-induced plasma formation. Powders, on the other hand, are difficult to analyze using LIBS since ejection and removal of the powder occur in the laser interaction region. The capability of analyzing powders is important in allowing for rapid analysis of suspicious materials, environmental samples, or trace contamination on surfaces since it most closely represents field samples (soil, small particles, debris etc.). The rapid, in situ analysis of samples, including nuclear materials, also reduces costs in sample collection, transportation, sample preparation, and analysis time. Here we demonstrate the detection of actinides in oxide powders and within a uranium ore sample as both pressed pellets and powders on carbon adhesive discs for spectral comparison. The acquired LIBS spectra for both forms of the samples differ in overall intensity but yield a similar distribution of atomic emission spectral lines. - Highlights: • LIBS analysis of mixed actinide samples: depleted uranium oxide and thorium oxide • LIBS analysis of actinide samples in powder form on carbon adhesive discs • Detection of uranium in a complex matrix (uranium ore) as a precursor to analyzing uranium in environmental samples.

  13. Laser induced breakdown spectroscopy (LIBS) applied to stratigrafic elemental analysis and optical coherence tomography (OCT) to damage determination of cultural heritage Brazilian coins

    Science.gov (United States)

    M. Amaral, Marcello; Raele, Marcus P.; Z. de Freitas, Anderson; Zahn, Guilherme S.; Samad, Ricardo E.; D. Vieira, Nilson, Jr.; G. Tarelho, Luiz V.

    2009-07-01

    This work presents a compositional characterization of 1939's Thousand "Réis" and 1945's One "Cruzeiro" Brazilian coins, forged on aluminum bronze alloy. The coins were irradiated by a Q-switched Nd:YAG laser with 4 ns pulse width and energy of 25mJ emitting at 1064nm reaching 3.1010Wcm-2 (assured condition for stoichiometric ablation), forming a plasma in a small fraction of the coin. Plasma emission was collected by an optical fiber system connected to an Echelle spectrometer. The capability of LIBS to remove small fraction of material was exploited and the coins were analyzed ablating layer by layer from patina to the bulk. The experimental conditions to assure reproductivity were determined by evaluation of three plasma paramethers: ionization temperature using Saha-Boltzmann plot, excitation temperature using Boltzmann plot, plasma density using Saha-Boltzmann plot and Stark broadening. The Calibration-Free LIBS technique was applied to both coins and the analytical determination of elemental composition was employed. In order to confirm the Edict Law elemental composition the results were corroborated by Neutron Activation Analysis (NAA). In both cases the results determined by CF-LIBS agreed to with the Edict Law and NAA determination. Besides the major components for the bronze alloy some other impurities were observed. Finally, in order to determine the coin damage made by the laser, the OCT (Optical Coherence Tomography) technique was used. After tree pulses of laser 54μg of coin material were removed reaching 120μm in depth.

  14. Laser-Induced Breakdown Spectroscopy Based Protein Assay for Cereal Samples.

    Science.gov (United States)

    Sezer, Banu; Bilge, Gonca; Boyaci, Ismail Hakki

    2016-12-14

    Protein content is an important quality parameter in terms of price, nutritional value, and labeling of various cereal samples. However, conventional analysis methods, namely, Kjeldahl and Dumas, have major drawbacks such as long analysis time, titration mistakes, and carrier gas dependence with high purity. For this reason, there is an urgent need for rapid, reliable, and environmentally friendly technologies for protein analysis. The present study aims to develop a new method for protein analysis in wheat flour and whole meal by using laser-induced breakdown spectroscopy (LIBS), which is a multielemental, fast, and simple spectroscopic method. Unlike the Kjeldahl and Dumas methods, it has potential to analyze a high number of samples in considerably short time. In the study, nitrogen peaks in LIBS spectra of wheat flour and whole meal samples with different protein contents were correlated with results of the standard Dumas method with the aid of chemometric methods. A calibration graph showed good linearity with the protein content between 7.9 and 20.9% and a 0.992 coefficient of determination (R(2)). The limit of detection was calculated as 0.26%. The results indicated that LIBS is a promising and reliable method with its high sensitivity for routine protein analysis in wheat flour and whole meal samples.

  15. Laser Induced Breakdown Spectroscopy in archeometry: A review of its application and future perspectives

    Science.gov (United States)

    Spizzichino, Valeria; Fantoni, Roberta

    2014-09-01

    Laser Induced Breakdown Spectroscopy (LIBS) in the last decades has been more and more applied to the field of Cultural Heritage with great results obtained either alone or in combination with complementary laser techniques. Its ability to analyze, with a minimal loss, different kinds of materials in laboratory, in situ and even in hostile environments has been highly appreciated. The main aim of this paper is to present a review of LIBS applications in the interdisciplinary field of archeometry. The LIBS technique is shortly described both from a theoretical and practical point of view, discussing the instrumental setup, also in comparison with typical features of laser induced fluorescence (LIF) and Raman spectroscopy apparata. The complementary with multivariate analysis, a method that can help in reducing data set dimensions and in pulling out effective information, is stressed. In particular the role of LIBS in Cultural Heritage material characterization, recognition of fakes and indirect dating is described, reporting general considerations and case studies on metal alloys, mural paintings, decorated ceramics, glasses, stones and gems.

  16. Improved accuracy in quantitative laser-induced breakdown spectroscopy using sub-models

    Science.gov (United States)

    Anderson, Ryan B.; Clegg, Samuel M.; Frydenvang, Jens; Wiens, Roger C.; McLennan, Scott; Morris, Richard V.; Ehlmann, Bethany; Dyar, M. Darby

    2017-03-01

    Accurate quantitative analysis of diverse geologic materials is one of the primary challenges faced by the laser-induced breakdown spectroscopy (LIBS)-based ChemCam instrument on the Mars Science Laboratory (MSL) rover. The SuperCam instrument on the Mars 2020 rover, as well as other LIBS instruments developed for geochemical analysis on Earth or other planets, will face the same challenge. Consequently, part of the ChemCam science team has focused on the development of improved multivariate analysis calibrations methods. Developing a single regression model capable of accurately determining the composition of very different target materials is difficult because the response of an element's emission lines in LIBS spectra can vary with the concentration of other elements. We demonstrate a conceptually simple "sub-model" method for improving the accuracy of quantitative LIBS analysis of diverse target materials. The method is based on training several regression models on sets of targets with limited composition ranges and then "blending" these "sub-models" into a single final result. Tests of the sub-model method show improvement in test set root mean squared error of prediction (RMSEP) for almost all cases. The sub-model method, using partial least squares (PLS) regression, is being used as part of the current ChemCam quantitative calibration, but the sub-model method is applicable to any multivariate regression method and may yield similar improvements.

  17. Improved accuracy in quantitative laser-induced breakdown spectroscopy using sub-models

    Science.gov (United States)

    Anderson, Ryan; Clegg, Samuel M.; Frydenvang, Jens; Wiens, Roger C.; McLennan, Scott M.; Morris, Richard V.; Ehlmann, Bethany L.; Dyar, M. Darby

    2017-01-01

    Accurate quantitative analysis of diverse geologic materials is one of the primary challenges faced by the Laser-Induced Breakdown Spectroscopy (LIBS)-based ChemCam instrument on the Mars Science Laboratory (MSL) rover. The SuperCam instrument on the Mars 2020 rover, as well as other LIBS instruments developed for geochemical analysis on Earth or other planets, will face the same challenge. Consequently, part of the ChemCam science team has focused on the development of improved multivariate analysis calibrations methods. Developing a single regression model capable of accurately determining the composition of very different target materials is difficult because the response of an element’s emission lines in LIBS spectra can vary with the concentration of other elements. We demonstrate a conceptually simple “sub-model” method for improving the accuracy of quantitative LIBS analysis of diverse target materials. The method is based on training several regression models on sets of targets with limited composition ranges and then “blending” these “sub-models” into a single final result. Tests of the sub-model method show improvement in test set root mean squared error of prediction (RMSEP) for almost all cases. The sub-model method, using partial least squares regression (PLS), is being used as part of the current ChemCam quantitative calibration, but the sub-model method is applicable to any multivariate regression method and may yield similar improvements.

  18. Laser-induced breakdown spectroscopy of scaled steel samples taken from continuous casting blooms

    Science.gov (United States)

    Meinhardt, Christoph; Sturm, Volker; Fleige, Rüdiger; Fricke-Begemann, Cord; Noll, Reinhard

    2016-09-01

    To analyse continuous casting steel blooms a removal of non-representative surface layers is required prior to the analysis. In this work, an optimized process is developed to ablate such layers and to analyse the bulk material underneath with laser-induced breakdown spectroscopy (LIBS). A high ablation rate is crucial since the time slot for an inline analysis is limited, e.g. to metallic layers and typically have thicknesses from 200 μm to 600 μm each. The ablation behaviour of the oxide differs significantly from that of the metallic layers. An operation scheme for inline material identification is worked out to perform ablation and analysis with a single laser source. During the ablation phase and the subsequent measurement phase the laser source is operated with individually tailored parameters. A total penetration depth exceeding 1 mm in steel can be achieved within 20 s of ablation. Thereby the influence of non-representative surface layers on the following LIBS measurement can be suppressed to a large extent. For chromium, relative root mean square errors of predictions of less than 13% were achieved on high alloy samples with up to 16 m.-% Cr and on low alloy samples with Cr contents below 2 m.-%.

  19. Laser Induced Breakdown Spectroscopy of meteorites as a probe of the early solar system

    Energy Technology Data Exchange (ETDEWEB)

    Dell' Aglio, M., E-mail: marcella.dellaglio@ba.imip.cnr.it [CNR-IMIP, Via Amendola 122/D, 70126 Bari (Italy); De Giacomo, A. [CNR-IMIP, Via Amendola 122/D, 70126 Bari (Italy); Chemistry Department, University of Bari, Via Orabona 4, 70126 Bari (Italy); Gaudiuso, R.; De Pascale, O. [CNR-IMIP, Via Amendola 122/D, 70126 Bari (Italy); Longo, S. [Chemistry Department, University of Bari, Via Orabona 4, 70126 Bari (Italy); INAF-Osservatorio Astrofisico di Arcetri, Largo Enrico Fermi 5, Firenze (Italy)

    2014-11-01

    This paper presents an evaluation of Laser Induced Breakdown Spectroscopy (LIBS) as a technique for gathering data relevant to Solar System geophysics. Two test cases were demonstrated: elemental analysis of chondrules in a chondrite meteorite, and space- resolved analysis of the interface between kamacite and taenite crystals in an octahedrite iron meteorite. In particular most major and minor elements (Fe, Mg, Si, Ti, Al, Cr, Mn, Ca, Fe, Ni, Co) in Sahara 98222 (chondrite) and its chondrules, as well as the profile of Ni content in Toluca (iron meteorite), were determined with the Calibration Free (CF) method. A special attention was devoted to exploring the possibilities offered by variants of the basic technique, such as the use of Fe I Boltzmann distribution as an intensity calibration method of the spectroscopic system, and the use of spatially resolved analysis. - Highlights: • LIBS of meteorites can supply data relevant to the early evolution of solar system. • CF-LIBS was applied to two different test cases. • Chemical identification of chondrules embedded in a chondrite meteorite • Experimental and theoretical profiles of Ni content in an iron meteorite.

  20. Statistical Classification of Soft Solder Alloys by Laser-Induced Breakdown Spectroscopy: Review of Methods

    Science.gov (United States)

    Zdunek, R.; Nowak, M.; Pliński, E.

    2016-02-01

    This paper reviews machine-learning methods that are nowadays the most frequently used for the supervised classification of spectral signals in laser-induced breakdown spectroscopy (LIBS). We analyze and compare various statistical classification methods, such as linear discriminant analysis (LDA), quadratic discriminant analysis (QDA), partial least-squares discriminant analysis (PLS-DA), soft independent modeling of class analogy (SIMCA), support vector machine (SVM), naive Bayes method, probabilistic neural networks (PNN), and K-nearest neighbor (KNN) method. The theoretical considerations are supported with experiments conducted for real soft-solder-alloy spectra obtained using LIBS. We consider two decision problems: binary and multiclass classification. The former is used to distinguish overheated soft solders from their normal versions. The latter aims to assign a testing sample to a given group of materials. The measurements are obtained for several laser-energy values, projection masks, and numbers of laser shots. Using cross-validation, we evaluate the above classification methods in terms of their usefulness in solving both classification problems.

  1. Spatial confinement in laser-induced breakdown spectroscopy

    Science.gov (United States)

    Li, Xingwen; Yang, Zefeng; Wu, Jian; Wei, Wenfu; Qiu, Yan; Jia, Shenli; Qiu, Aici

    2017-01-01

    The spatial confinement of plasma produced by a nanosecond laser is investigated using time resolved spectroscopy, fast imaging, interferometry, and numerical computation. The dynamics of the plasma, depending on shock waves, laser power, and wall distances, are studied. Experimental results confirm that the plasma is constricted by the reflected shock associated with a temperature and density gradient. The peak laser power determines the initial plasma parameters which affect the spectral intensities and the velocity of the reflective shock waves. The wall distance determines the reflection time of the shocks, which in turn influences the time delay of the collision between the two reflective shocks. The numerical results reveal a fast propagation process surrounding the reflective shocks, which indicates that the velocity of the reflective shock wave is influenced by the density of the plasma. The maximum enhancement factor ~5.2 is realized at a delay time of 11.7 µs under a pulse laser energy of 180 mJ and a wall distance of 9 mm.

  2. Fast detection of tobacco mosaic virus infected tobacco using laser-induced breakdown spectroscopy

    Science.gov (United States)

    Peng, Jiyu; Song, Kunlin; Zhu, Hongyan; Kong, Wenwen; Liu, Fei; Shen, Tingting; He, Yong

    2017-03-01

    Tobacco mosaic virus (TMV) is one of the most devastating viruses to crops, which can cause severe production loss and affect the quality of products. In this study, we have proposed a novel approach to discriminate TMV-infected tobacco based on laser-induced breakdown spectroscopy (LIBS). Two different kinds of tobacco samples (fresh leaves and dried leaf pellets) were collected for spectral acquisition, and partial least squared discrimination analysis (PLS-DA) was used to establish classification models based on full spectrum and observed emission lines. The influences of moisture content on spectral profile, signal stability and plasma parameters (temperature and electron density) were also analysed. The results revealed that moisture content in fresh tobacco leaves would worsen the stability of analysis, and have a detrimental effect on the classification results. Good classification results were achieved based on the data from both full spectrum and observed emission lines of dried leaves, approaching 97.2% and 88.9% in the prediction set, respectively. In addition, support vector machine (SVM) could improve the classification results and eliminate influences of moisture content. The preliminary results indicate that LIBS coupled with chemometrics could provide a fast, efficient and low-cost approach for TMV-infected disease detection in tobacco leaves.

  3. Laser-Induced Breakdown Spectroscopy Coupled with Multivariate Chemometrics for Variety Discrimination of Soil

    Science.gov (United States)

    Yu, Ke-Qiang; Zhao, Yan-Ru; Liu, Fei; He, Yong

    2016-06-01

    The aim of this work was to analyze the variety of soil by laser-induced breakdown spectroscopy (LIBS) coupled with chemometrics methods. 6 certified reference materials (CRMs) of soil samples were selected and their LIBS spectra were captured. Characteristic emission lines of main elements were identified based on the LIBS curves and corresponding contents. From the identified emission lines, LIBS spectra in 7 lines with high signal-to-noise ratio (SNR) were chosen for further analysis. Principal component analysis (PCA) was carried out using the LIBS spectra at 7 selected lines and an obvious cluster of 6 soils was observed. Soft independent modeling of class analogy (SIMCA) and least-squares support vector machine (LS-SVM) were introduced to establish discriminant models for classifying the 6 types of soils, and they offered the correct discrimination rates of 90% and 100%, respectively. Receiver operating characteristic (ROC) curve was used to evaluate the performance of models and the results demonstrated that the LS-SVM model was promising. Lastly, 8 types of soils from different places were gathered to conduct the same experiments for verifying the selected 7 emission lines and LS-SVM model. The research revealed that LIBS technology coupled with chemometrics could conduct the variety discrimination of soil.

  4. Evaluation of sandstone surface relaxivity using laser-induced breakdown spectroscopy.

    Science.gov (United States)

    Washburn, Kathryn E; Sandor, Magdalena; Cheng, Yuesheng

    2017-02-01

    Nuclear magnetic resonance (NMR) relaxometry is a common technique used to assess the pore size of fluid-filled porous materials in a wide variety of fields. However, the NMR signal itself only provides a relative distribution of pore size. To calculate an absolute pore size distribution from the NMR data, the material's surface relaxivity needs to be known. Here, a method is presented using laser-induced breakdown spectroscopy (LIBS) to evaluate surface relaxivity in sandstones. NMR transverse and longitudinal relaxation was measured on a set of sandstone samples and the surface relaxivity was calculated from the pore size distribution determined with MICP measurements. Using multivariate analysis, it was determined that the LIBS data can predict with good accuracy the longitudinal (R(2)∼0.84) and transverse (R(2)∼0.79) surface relaxivity. Analysis of the regression coefficients shows significant influence from several elements. Some of these are elements previously established to have an effect on surface relaxivity, such as iron and manganese, while others are not commonly associated with surface relaxivity, such as cobalt and titanium. Furthermore, LIBS provides advantages compared to current methods to calibrate surface relaxivity in terms of speed, portability, and sample size requirements. While this paper focuses on geological samples, the method could potentially be expanded to other types of porous materials.

  5. Laser-induced breakdown spectroscopy: A versatile tool for monitoring traces in materials

    Indian Academy of Sciences (India)

    Shiwani Pandhija; A K Rai

    2008-03-01

    Laser-induced breakdown spectroscopy (LIBS) is an emerging technique for simultaneous multi-elemental analysis of solids, liquids and gases with minute or no sample preparation and thus revolutionized the area of on-line analysis technologies. The foundation for LIBS is a solid state, short-pulsed laser that is focused on a sample to generate a high-temperature plasma, and the emitted radiation from the excited atomic and ionic fragments produced within the plasma is characteristic of the elemental composition of the sample that can be detected and analyzed using a suitable optical spectrograph. In the present paper, the applicability of LIBS for different solid samples having homogeneous (silver ornament, aluminum plate) or heterogeneous composition (soil) using nanosecond laser pulses is discussed. Nanosecond pulse laser makes plasma at the sample surface even at very low pulse energies and also allows for precise ablation of the substrate material with little damage to the surrounding area. We have also studied the penetration of different heavy metals inside the soil surface.

  6. [Experimental study on chromium in gannan navel orange by laser-induced breakdown spectroscopy].

    Science.gov (United States)

    Xu, Yuan; Liu, Mu-Hua; Yao, Ming-Yin; Peng, Qiu-Mei; Chen, Tian-Bing; Zhang, Xu; Lin, Yong-Zeng

    2012-09-01

    It is a relatively new task to apply the laser induced breakdown spectroscopy (LIBS) to fruit samples. To apply LIBS technique in the field related to analysis of trace heavy metal element in fruits samples, we have done primary experiments using Gannan navel orange samples. The authors put the samples into different concentration gradient K2Cr2O7 solution and left it for 30 hours, and then we did the LIBS experiment, discriminated characteristic spectra of chromium element and recorded the peak intensity information. Weighing three grams of sample and determined chromium concentration in the samples by atomic absorption spectrophotometer using wet digestion. The calibration curve of the line intensities versus the concentrations of the Cr element was acquired by the Origin software. The authors found that the linear correlation coefficient is 0. 981 66. The calibration curve can be used for the quantitative analysis of chromium element with an unknown concentration in Gannan navel orange. The LIBS detection limit of Cr in the solution was 11.64 mg x g(-1) from the measured calibration curve. Experiment results showed that LIBS technique is a valid means for measuring and quantitatively analyzing the content of heavy metal elements in fruit samples.

  7. Determining spatial sodium distribution in fresh and aged bread using laser-induced breakdown spectroscopy

    NARCIS (Netherlands)

    Scholtes-Timmerman, M.; Heddes, C.; Noort, M.W.J.; Veen, S. van

    2013-01-01

    A fast and easy-to-use method using laser-induced breakdown spectroscopy (LIBS) was set up to determine Na (sodium) distribution in baked bread. Standard bread was made using a standard recipe and the amount of salt added was 0, 0.5, 1, 2, 4, 10, 15 and 20g corresponding to 0, 0.25, 0.5, 1.0, 2.0, 5

  8. Laser-induced breakdown spectroscopy application to control of the process of precious metal recovery and recycling

    Energy Technology Data Exchange (ETDEWEB)

    Legnaioli, S.; Lorenzetti, G.; Pardini, L. [Institute of Chemistry of Organometallic Compounds, Research Area of CNR, Via G. Moruzzi, 1-56124 Pisa (Italy); Palleschi, V., E-mail: vincenzo.palleschi@cnr.it [Institute of Chemistry of Organometallic Compounds, Research Area of CNR, Via G. Moruzzi, 1-56124 Pisa (Italy); Pace, D.M. Diaz [Instituto de Fisica ' Arroyo Seco' , Facultad de Ciencias Exactas, Paraje Arroyo Seco-(B7000GHG) Tandil (Argentina); Garcia, F. Anabitarte [Photonic Engineering Group, Universidad de Cantabria, Edificio I-D-i Telecomunicacion, Dpto. TEISA-39005 Santander (Spain); Grassi, R.; Sorrentino, F.; Carelli, G.; Francesconi, M.; Francesconi, F. [Marwan Technology, Largo Pontecorvo, 3-56127 Pisa Italy (Italy); Borgogni, R. [CABRO S.p.A.,Via Setteponti, 141-52100 Arezzo (Italy)

    2012-05-15

    In this paper, we discuss the application of laser-induced breakdown spectroscopy to precious metal alloys used for the control of the process of recovery and recycling of scraps and waste of industrial processes. In particular, the possibility to obtain sensitivity and trueness comparable to the current systems used in industrial environment in the quantitative determination of the elements of interest was explored. The present study demonstrates that laser-induced breakdown spectroscopy can be considered as a viable alternative to inductively coupled plasma optical emission spectrometry and X-ray fluorescence spectroscopy for the determination of recovered precious metals. The limits of detection obtained are of the order of 0.2 mg/g for all the elements considered. The maximum deviation with respect to the nominal concentrations is around 1 mg/g at concentrations around 20 mg/g (gold) corresponding to a relative error slightly higher than {+-} 5%. - Highlights: Black-Right-Pointing-Pointer We discuss application of LIBS for the analysis of recovered precious metals. Black-Right-Pointing-Pointer The advantages and drawbacks of LIBS vs. XRF are evidenced. Black-Right-Pointing-Pointer A strategy is devised for obtaining by LIBS limits of detection comparable to XRF. Black-Right-Pointing-Pointer The same strategy would provide trueness in analytical results comparable to XRF. Black-Right-Pointing-Pointer The time needed and the complexity of LIBS analysis would not exceed the XRF ones.

  9. Determination of a brass alloy concentration composition using calibration-free laser-induced breakdown spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Achouri, M.; Baba-Hamed, T.; Beldjilali, S. A., E-mail: sidahmed.beldjilali@univ-usto.dz; Belasri, A. [Université des Sciences et de la Technologie d’Oran Mohamed Boudiaf USTO-MB, LPPMCA (Algeria)

    2015-09-15

    Laser-induced breakdown spectroscopy (LIBS) is a technique that can provide qualitative and quantitative measurements of the characteristics of irradiated metals. In the present work, we have calculated the parameters of the plasma produced from a brass alloy sample under the action of a pulsed Nd: YAG laser operating at 1064 nm. The emission lines of copper atoms (Cu I), zinc atoms (Zn I), and lead atoms (Pb I), which are elements of a brass alloy composition, were used to investigate the parameters of the brass plasma. The spectral profiles of Cu, Zn, and Pb lines have been used to extract the electron temperature and density of the brass alloy plasma. The characteristics of Cu, Zn, and Pb were determined quantatively by the calibration-free LIBS (CF-LIBS) method considering for accurate analysis that the laser-induced ablated plasma is optically thin in local thermodynamic equilibrium conditions and the plasma ablation is stoichiometric. The Boltzmann plot method was used to evaluate the plasma temperature, and the Stark broadened profiles were used to determine the electron density. An algorithm based on the experimentally measured values of the intensity of spectral lines and the basic laws of plasma physics was developed for the determination of Cu, Zn, and Pb concentrations in the brass sample. The concentrations C{sub CF-LIBS} calculated by CF-LIBS and the certified concentrations C{sub certified} were very close.

  10. Quantitative determination of sulfur content in concrete with laser-induced breakdown spectroscopy

    Science.gov (United States)

    Weritz, F.; Ryahi, S.; Schaurich, D.; Taffe, A.; Wilsch, G.

    2005-08-01

    Laser-induced breakdown spectroscopy has been employed for the investigation of the sulfur content of concrete. Sulfur compounds are a natural but minor component in building materials. The ingress of sulfates or sulfuric acid constitutes a major risk of chemical aggression for concrete. There is a need for a fast method, which can be used on-site and is able to investigate a wide range of different measuring points, so that damages can be characterized. For quantitative determination the sulfur spectral line at 921.3 nm is used. The optimum ambient atmosphere has been determined by comparison of measurements accomplished under air, argon and helium atmosphere. Reference samples have been produced and calibration curves have been determined, the results of LIBS measurements are compared with results from chemical analysis. Defining a limit for the intensity ratio of a calcium and a oxygen spectral line can reduce the influence of the heterogeneity of the material, so that only spectra with a high amount of cementitious material are evaluated. Depth profiles and spatial resolved sulfur distributions are presented measured on concrete cores originating from a highly sulfate contaminated clarifier.

  11. Quantitative determination of calcium, magnesium, and zinc in fingernails by laser-induced breakdown spectroscopy.

    Science.gov (United States)

    Rusak, David A; Zeleniak, Ann E; Obuhosky, Jillian L; Holdren, Scott M; Noldy, Craig A

    2013-12-15

    Quantitative determination of Ca, Mg, and Zn in fingernails was performed with laser-induced breakdown spectroscopy. Two different methods of producing solid standards for calibration were explored - preparation of keratin pellets and deposition of aqueous solutions to filter papers. Measurements of the temperature and electron density of the plasma produced on keratin pellets, filter paper, and nails were performed, and it was determined that the standards prepared on filter paper gave plasma temperatures and electron densities closer to those observed on the nails. The ablation rate of the filter paper was also more similar to that of the nails. Using calibration curves produced using these filter paper standards, Ca, Mg, and Zn were determined in fingernails of 11 subjects. For comparison, the same samples were digested and atomic absorption was used to determine the same three elements. The differences in results are discussed in light of sample homogeneity and instrumental precision; the best agreement was obtained for determination of Zn. The work suggests that the filter paper method of standard preparation may be appropriate for LIBS analysis of other samples that give relatively low temperature, low electron density plasmas (i.e., polymers).

  12. High-Resolution Laser-Induced Breakdown Spectroscopy used in Homeland Security and Forensic Applications

    Energy Technology Data Exchange (ETDEWEB)

    Martin, Madhavi Z [ORNL; Wullschleger, Stan D [ORNL; Vass, Arpad Alexander [ORNL; Martin, Rodger Carl [ORNL; Grissino-Mayer, Henri [ORNL

    2006-01-01

    The technique of laser-induced breakdown spectroscopy (LIBS) to detect elements for a variety of homeland security applications such as nuclear materials identification and inventory,and forensic applications has been demonstrated. For nuclear materials applications, we detected and profiled metals in coatings that were used to encapsulate nuclear fuel. Multivariate analysis has been successfully employed in the quantification of elements present in treated wood and engineered wood composites. These examples demonstrate that LIBS-based techniques are inherently well suited for diverse environmental applications related to homeland security. Three key advantages are evident: (1) small samples (mg) are sufficient; (2) samples can be analyzed by LIBS very rapidly, and (3) biological materials such as human and animal bones and wood can be analyzed with minimal sample preparation. For forensic applications they have used LIBS to determine differences in animal and human bones. They have also applied this technique in the determination of counterfeit and non-counterfeit currency. They recently applied LIBS in helping to solve a murder case.

  13. Rapid detection of soils contaminated with heavy metals and oils by laser induced breakdown spectroscopy (LIBS).

    Science.gov (United States)

    Kim, Gibaek; Kwak, Jihyun; Kim, Ki-Rak; Lee, Heesung; Kim, Kyoung-Woong; Yang, Hyeon; Park, Kihong

    2013-12-15

    A laser induced breakdown spectroscopy (LIBS) coupled with the chemometric method was applied to rapidly discriminate between soils contaminated with heavy metals or oils and clean soils. The effects of the water contents and grain sizes of soil samples on LIBS emissions were also investigated. The LIBS emission lines decreased by 59-75% when the water content increased from 1.2% to 7.8%, and soil samples with a grain size of 75 μm displayed higher LIBS emission lines with lower relative standard deviations than those with a 2mm grain size. The water content was found to have a more pronounced effect on the LIBS emission lines than the grain size. Pelletizing and sieving were conducted for all samples collected from abandoned mining areas and military camp to have similar water contents and grain sizes before being analyzed by the LIBS with the chemometric analysis. The data show that three types of soil samples were clearly discerned by using the first three principal components from the spectral data of soil samples. A blind test was conducted with a 100% correction rate for soil samples contaminated with heavy metals and oil residues.

  14. A study of association between fingernail elements and osteoporosis by laser-induced breakdown spectroscopy

    Science.gov (United States)

    Bahreini, Maryam; Hosseinimakarem, Zahra; Hassan Tavassoli, Seyed

    2012-09-01

    Laser induced breakdown spectroscopy (LIBS) is used to investigate the possible effect of osteoporosis on the elemental composition of fingernails. Also, the ability to classify healthy, osteopenic, and osteoporotic subjects based on their fingernail spectra has been examined. 46 atomic and ionic emission lines belonging to 13 elements, which are dominated by calcium and magnesium, have been identified. Measurements are carried out on fingernail clippings of 99 subjects including 27 healthy, 47 osteopenic, and 25 osteoporotic subjects. The Pearson correlations between spectral intensities of different elements of fingernail and age and bone mineral densities (BMDs) in nail samples are calculated. Correlations between line intensities of some elements such as sodium and potassium, calcium and iron, magnesium and silicon and also between some fingernail elements, BMD, and age are observed. Although some of these correlations are weak, some information about mineral metabolism can be deduced from them. Discrimination between nail samples of healthy, osteopenic, and osteoporotic subjects is shown to be somehow possible by a discriminant function analysis using 46 atomic emission lines of the LIBS spectra as input variables. The results of this study provide some evidences for association between osteoporosis and elemental composition of fingernails measured by LIBS.

  15. Laser induced breakdown spectroscopy of human liver samples with Wilson's disease

    Science.gov (United States)

    Grolmusová, Zuzana; Horňáčková, Michaela; Plavčan, Jozef; Kopáni, Martin; Babál, Pavel; Veis, Pavel

    2013-08-01

    Laser induced breakdown spectroscopy (LIBS) is an elemental analytical technique with various applications. The paper demonstrates the first LIBS measurements of human liver samples for the purpose of detecting the higher copper content related with the advanced stage of Wilson's disease. These measurements were implemented using a Nd:YAG laser working at the wavelength of 532 nm and an echelle type spectrometer equipped with an intensified CCD camera allowing for a wide spectral range coverage (200-950 nm) and rapid camera gating (minimum gating time of 5 ns). Seven liver samples with suspected Wilson's disease and five reference samples were investigated. The main parameter of interest was the Cu/C ratio obtained at first from spectra and secondly directly from an iCCD image. Our experiment is a pilot study, which shows LIBS analysis of human liver samples for the purpose of detecting the normal and higher copper content for the first time. The method proved to be a quick and a low-cost approach for the detection of pathological accumulation of copper in the affected tissue.

  16. Repeatability improvement of laser-induced breakdown spectroscopy using an auto-focus system

    Science.gov (United States)

    Ashrafkhani, Behnam; Bahreini, Maryam; Tavassoli, Seyed Hassan

    2015-05-01

    Laser-induced breakdown spectroscopy (LIBS) is a novel technique for elemental analysis of materials. The repeatability of LIBS results is an important issue in many applications. Many factors influence the repeatability of LIBS results. The aim of this study is to examine the effect of laser beam focusing position or lens to sample distance (LTSD) as one of the most important factors influencing LIBS spectra. A point auto-focus system is designed and applied to provide the same lens to sample distance in every LIBS experiment. This system is employed and the result is compared to that of non-auto-focus technique on samples with different degrees of evenness such as aluminum, paper, tape and human fingernail. The standard deviation of this experiment is measured in the range of 4 to 26 μm. Then, spectrum's repeatability is examined with two samples of aluminum and human fingernail. The standard deviation of spectra is considerably reduced. In conclusion, repeatability of LIBS results could be optimized by using the auto-focus system.

  17. Studying the enhanced phytoremediation of lead contaminated soils via laser induced breakdown spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Hassan, M. [National Institute of Laser Enhanced Science (NILES), Cairo University, Giza (Egypt); Sighicelli, M.; Lai, A.; Colao, F. [ENEA, Dept. FIM, Via Enrico Fermi 00044 Frascati RM (Italy); Ahmed, A.H. Hanafy [Faculty of Agriculture, Cairo University, Giza (Egypt); Fantoni, R. [ENEA, Dept. FIM, Via Enrico Fermi 00044 Frascati RM (Italy); Harith, M.A. [National Institute of Laser Enhanced Science (NILES), Cairo University, Giza (Egypt)], E-mail: mharithm@niles.edu.eg

    2008-10-15

    Phytoremediation popularly known as 'green clean technology' is a new promising technology used for toxic contaminants removal from the environment such as heavy metals (HMs), adopting suitable plants. This concept is increasingly being adopted as it is a cost effective and environmentally friendly alternative to traditional methods of treatment. This study was focused on using scented geranium, Pelargonium zonale, as accumulator or hyperaccumulator plant for natural lead extraction from artificially contaminated soil with different Pb concentrations (0, 2000, 5000, 7000 ppm). Utilization of EDTA as a chelator, that would permit higher metal availability and uptake by the tested plants roots, was also tested. Laser Induced Breakdown Spectroscopy (LIBS) was used to follow up Pb concentrations in both soil and plant green harvestable parts known as shoots, before, during and after lead addition in soil. LIBS measurements were conducted in a microdestructive way by focusing a high energy Nd:YAG laser, emitting at 1064 nm, on plant and soil samples previously dried, homogenized and pressed in pellets. The emitted LIBS spectra were acquired by a gated CCD after dispersion on a monochromator and analyzed to retrieve relative concentrations of the selected HM both in the soil and on plants as a function of the time after doping and eventual chelator addition. EDTA was found to enhance Pb uptake from the soil which increased with time, good correlation was found between LIBS and ICP-OES results of plant tissues spectrochemical analysis.

  18. Studying the enhanced phytoremediation of lead contaminated soils via laser induced breakdown spectroscopy

    Science.gov (United States)

    Hassan, M.; Sighicelli, M.; Lai, A.; Colao, F.; Ahmed, A. H. Hanafy; Fantoni, R.; Harith, M. A.

    2008-10-01

    Phytoremediation popularly known as 'green clean technology' is a new promising technology used for toxic contaminants removal from the environment such as heavy metals (HMs), adopting suitable plants. This concept is increasingly being adopted as it is a cost effective and environmentally friendly alternative to traditional methods of treatment. This study was focused on using scented geranium, Pelargonium zonale, as accumulator or hyperaccumulator plant for natural lead extraction from artificially contaminated soil with different Pb concentrations (0, 2000, 5000, 7000 ppm). Utilization of EDTA as a chelator, that would permit higher metal availability and uptake by the tested plants roots, was also tested. Laser Induced Breakdown Spectroscopy (LIBS) was used to follow up Pb concentrations in both soil and plant green harvestable parts known as shoots, before, during and after lead addition in soil. LIBS measurements were conducted in a microdestructive way by focusing a high energy Nd:YAG laser, emitting at 1064 nm, on plant and soil samples previously dried, homogenized and pressed in pellets. The emitted LIBS spectra were acquired by a gated CCD after dispersion on a monochromator and analyzed to retrieve relative concentrations of the selected HM both in the soil and on plants as a function of the time after doping and eventual chelator addition. EDTA was found to enhance Pb uptake from the soil which increased with time, good correlation was found between LIBS and ICP-OES results of plant tissues spectrochemical analysis.

  19. Multi-elemental mapping of a speleothem using laser-induced breakdown spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Q.L.; Motto-Ros, V. [Universite de Lyon, Universite Lyon 1, Villeurbanne, CNRS, UMR5579, LASIM F-69622, Lyon (France); Lei, W.Q. [Universite de Lyon, Universite Lyon 1, Villeurbanne, CNRS, UMR5579, LASIM F-69622, Lyon (France); State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai (China); Boueri, M. [Universite de Lyon, Universite Lyon 1, Villeurbanne, CNRS, UMR5579, LASIM F-69622, Lyon (France); Zheng, L.J.; Zeng, H.P. [State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai (China); Bar-Matthews, M.; Ayalon, A. [Geological Survey of Israel, 30 Malkhei Israel St., Jerusalem (Israel); Panczer, G. [Universite de Lyon, Universite Lyon 1, Villeurbanne, CNRS UMR 5620, LPCML F-69622, Lyon (France); Yu, J., E-mail: jin.yu@lasim.univ-lyon1.f [Universite de Lyon, Universite Lyon 1, Villeurbanne, CNRS, UMR5579, LASIM F-69622, Lyon (France)

    2010-08-15

    Speleothems represent an important record of the paleoclimate, and more generally past environmental changes thanks to their laminar structure which is related to variations in rainfall and vegetation throughout the seasons and to their elemental as well as structural compositions which are sensitive to climatic and environmental conditions during their growth. Studies of their composition, especially those with spatial resolution, reveal rich information for paleoclimatology. In this paper, we demonstrate that laser-induced breakdown spectroscopy (LIBS) provides a suitable tool for elemental analysis and especially for 2-dimensional elemental mapping of speleothems. Main, minor, as well as trace elements can be analyzed with this technique. The temporal evolution of the induced plasma is first studied in order to determine a suitable detection window for emission spectrum recording following the impact of the laser pulse on the sample. The matrix effect is then evaluated with a scan on the sample surface by measuring the electron density and the temperature of the plasmas at different positions of the analyzed surface. Concentration mapping is performed for minor and trace elements such as Na, Mg, Al, Si, K, Fe and Sr, by measuring relative variations of line emission intensities from these elements. Finally, correlations in concentration among detected elements are determined. Groups of correlated elements can be attributed to different mineralogical phases.

  20. Application of laser-induced breakdown spectroscopy in carbon sequestration research and development

    Indian Academy of Sciences (India)

    Jinesh Jain; Dustin Mcintyre; Krishna Ayyalasomayajula; Vivek Dikshit; Christian Goueguel; F Yu-Yueh; Jagdish Singh

    2014-08-01

    The success of carbon capture and storage (CCS) programme relies on the long-term isolation of CO2 from the atmosphere. Therefore, technologies concomitant to physical storage of CO2 such as reliable measurement, monitoring, and verification (MMV) techniques are needed to ensure that the integrity of the storage site is maintained. We propose the use of laser-induced breakdown spectroscopy (LIBS) analytical technique to detect carbon dioxide leaks to aid in the successful application of CCS. LIBS has a real-time monitoring capability and can be reliably used for the elemental and isotopic analysis of solid, liquid, and gas samples. The flexibility of probe design and use of fibre optics make it a suitable technique for real-time measurements in harsh conditions and at hard-to-reach places. Proposed monitoring with LIBS includes terrestrial soil samples, water samples from monitoring wells or from different formations, air samples from monitoring wells or suspected leakage areas. This work details the laboratory scale experiments to measure carbon contents in soil, aqueous, and air samples. The potential of the technology for measurements in high-pressure, high-temperature conditions has been discussed.

  1. [A method for time-resolved laser-induced breakdown spectroscopy measurement].

    Science.gov (United States)

    Pan, Cong-Yuan; Han, Zhen-Yu; Li, Chao-Yang; Yu, Yun-Si; Wang, Sheng-Bo; Wang, Qiu-Ping

    2014-04-01

    Laser-Induced Breakdown Spectroscopy (LIBS) is strongly time related. Time-resolved LIBS measurement is an important technique for the research on laser induced plasma evolution and self-absorption of the emission lines. Concerning the temporal characteristics of LIBS spectrum, a method is proposed in the present paper which can achieve micros-scale time-resolved LIBS measurement by using general ms-scale detector. By setting different integration delay time of the ms-scale spectrum detector, a series of spectrum are recorded. And the integration delay time interval should be longer than the worst temporal precision. After baseline correction and spectrum fitting, the intensity of the character line was obtained. Calculating this intensity with differential method at a certain time interval and then the difference value is the time-resolved line intensity. Setting the plasma duration time as X-axis and the time-resolved line intensity as Y-axis, the evolution curve of the character line intensity can be plotted. Character line with overlap-free and smooth background should be a priority to be chosen for analysis. Using spectrometer with ms-scale integration time and a control system with temporal accuracy is 0.021 micros, experiments carried out. The results validate that this method can be used to characterize the evolution of LIBS characteristic lines and can reduce the cost of the time-resolved LIBS measurement system. This method makes high time-resolved LIBS spectrum measurement possible with cheaper system.

  2. [High Precision Identification of Igneous Rock Lithology by Laser Induced Breakdown Spectroscopy].

    Science.gov (United States)

    Wang, Chao; Zhang, Wei-gang; Yan, Zhi-quan

    2015-09-01

    In the field of petroleum exploration, lithology identification of finely cuttings sample, especially high precision identification of igneous rock with similar property, has become one of the geological problems. In order to solve this problem, a new method is proposed based on element analysis of Laser-Induced Breakdown Spectroscopy (LIBS) and Total Alkali versus Silica (TAS) diagram. Using independent LIBS system, factors influencing spectral signal, such as pulse energy, acquisition time delay, spectrum acquisition method and pre-ablation are researched through contrast experiments systematically. The best analysis conditions of igneous rock are determined: pulse energy is 50 mJ, acquisition time delay is 2 μs, the analysis result is integral average of 20 different points of sample's surface, and pre-ablation has been proved not suitable for igneous rock sample by experiment. The repeatability of spectral data is improved effectively. Characteristic lines of 7 elements (Na, Mg, Al, Si, K, Ca, Fe) commonly used for lithology identification of igneous rock are determined, and igneous rock samples of different lithology are analyzed and compared. Calibration curves of Na, K, Si are generated by using national standard series of rock samples, and all the linearly dependent coefficients are greater than 0.9. The accuracy of quantitative analysis is investigated by national standard samples. Element content of igneous rock is analyzed quantitatively by calibration curve, and its lithology is identified accurately by the method of TAS diagram, whose accuracy rate is 90.7%. The study indicates that LIBS can effectively achieve the high precision identification of the lithology of igneous rock.

  3. Parameters Optimization of Laser-Induced Breakdown Spectroscopy Experimental Setup for the Case with Beam Expander

    Science.gov (United States)

    Wang, Xin; Zhang, Lei; Fan, Juanjuan; Li, Yufang; Gong, Yao; Dong, Lei; Ma, Weiguang; Yin, Wangbao; Jia, Suotang

    2015-11-01

    Improvement of measurement precision and repeatability is one of the issues currently faced by the laser-induced breakdown spectroscopy (LIBS) technique, which is expected to be capable of precise and accurate quantitative analysis. It was found that there was great potential to improve the signal quality and repeatability by reducing the laser beam divergence angle using a suitable beam expander (BE). In the present work, the influences of several experimental parameters for the case with BE are studied in order to optimize the analytical performances: the signal to noise ratio (SNR) and the relative standard deviation (RSD). We demonstrate that by selecting the optimal experimental parameters, the BE-included LIBS setup can give higher SNR and lower RSD values of the line intensity normalized by the whole spectrum area. For validation purposes, support vector machine (SVM) regression combined with principal component analysis (PCA) was used to establish a calibration model to realize the quantitative analysis of the ash content. Good agreement has been found between the laboratory measurement results from the LIBS method and those from the traditional method. The measurement accuracy presented here for ash content analysis is estimated to be 0.31%, while the average relative error is 2.36%. supported by the 973 Program of China (No. 2012CB921603), National Natural Science Foundation of China (Nos. 61475093, 61127017, 61178009, 61108030, 61378047, 61275213, 61475093, and 61205216), the National Key Technology R&D Program of China (No. 2013BAC14B01), the Shanxi Natural Science Foundation (Nos. 2013021004-1 and 2012021022-1), the Shanxi Scholarship Council of China (Nos. 2013-011 and 2013-01), and the Program for the Outstanding Innovative Teams of Higher Learning Institutions of Shanxi, China

  4. Laser induced spectroscopy breakdown (LIBS) application to heavy metal detection in soils; Applicazioni della tecnica Laser induced breakdown spectroscopy (LIBS) alla determinazione dei metalli pesanti nei suoli

    Energy Technology Data Exchange (ETDEWEB)

    Barbini, R.; Fantoni, R.; Palucci, A.; Ribezzo, S.; Colao, F. [ENEA, Centro Ricerche Frascati, Frascati, RM (Italy). Div. Fisica Applicata; Capitelli, F. [Bari, Univ., Bari (Italy). Dipt. di Biologia e Chimica Agroforestale ed Ambientale

    2000-07-01

    LIBS (Laser induced breakdown spectroscopy) is a new spectroscopic technique suitable to the use in the analysis of samples of environmental interest, such as soils and rocks, and of industrial interest, such as alloys. Results dealing with the application of the technique to heterogeneous soil samples certified by Ispra Joint Research Centre in the contest of heavy metals (Cd, Cr, Cu, Fe, Mn, Ni, Pb, Zn) with an agronomical interest are presented in this report. In the LIBS technique, a high power laser beam is focused onto the sample in order to generate a small volume of plasma at its surface. Emissions from single atomic species are collected by a lens system coupled to an optical fiber bundle, dispersed on a monochromator and analyzed by an iCCD. the identification and the assignment of emission lines relevant to single atomic species allows to determine the sample elemental composition and, after calibration against reference samples, to perform quantitative analysis for a large number of species. This technique requires no sample pre-treatment, a part from eventually compacting powders by mechanical press. This is a considerable advantage with respect to traditional spectroscopic techniques, such as the ICP (Inductively Coupled Plasma) which needs sample mineralization by acid attack. Measurements performed on soil samples by means of the LIBS technique at ENEA Frascati were compared with the results obtained by ICP, which is considered a traditional technique for this kind of analysis. Results showed a general overestimation of the LIBS values with respect to the ICP ones, probably due to differences in lytologic matrix between the analyzed samples and the standard. The phenomenon is usually referred to the matrix effect, which is held responsible for the deviation from linearity between single element concentration and its row intensity. The effect is due to local plasma density variations and limit the correlation between the plasma elemental composition

  5. Chemical characterization of single micro- and nano-particles by optical catapulting-optical trapping-laser-induced breakdown spectroscopy

    Science.gov (United States)

    Fortes, Francisco J.; Fernández-Bravo, Angel; Javier Laserna, J.

    2014-10-01

    Spectral identification of individual micro- and nano-sized particles by the sequential intervention of optical catapulting, optical trapping and laser-induced breakdown spectroscopy is presented. The three techniques are used for different purposes. Optical catapulting (OC) serves to put the particulate material under inspection in aerosol form. Optical trapping (OT) permits the isolation and manipulation of individual particles from the aerosol, which are subsequently analyzed by laser-induced breakdown spectroscopy (LIBS). Once catapulted, the dynamics of particle trapping depends both on the laser beam characteristics (power and intensity gradient) and on the particle properties (size, mass and shape). Particles are stably trapped in air at atmospheric pressure and can be conveniently manipulated for a precise positioning for LIBS analysis. The spectra acquired from the individually trapped particles permit a straightforward identification of the material inspected. Variability of LIBS signal for the inspection of Ni microspheres was 30% relative standard deviation. OC-OT-LIBS permits the separation of particles in a heterogeneous mixture and the subsequent analysis of the isolated particle of interest. In order to evaluate the sensitivity of the approach, the number of absolute photons emitted by a single trapped particle was calculated. The limit of detection (LOD) for Al2O3 particles was calculated to be 200 attograms aluminium.

  6. Recognition of spectral identifier from green coffee beans of arabica and robusta varieties using laser-induced breakdown spectroscopy

    Science.gov (United States)

    Anggraeni, Karina; Nasution, Aulia; Suyanto, Hery

    2016-11-01

    Coffee is one of the world's commodity that is cultivated in more than 50 countries. Production of coffee in Indonesia is positioned of fourth rank in the world, after Brazil, Vietnam, and Colombia. There are two varieties of coffee grown in Indonesia, i.e. the arabica and robusta. The chemical compositions between arabica and robusta are different each other. A trained coffee tester can distinguish these differences from its taste, but it is very subjective. Laser-Induced Breakdown Spectroscopy (LIBS) is a spectroscopic technique based on the analysis of micro-plasma induced on the surface sample after being shot with a laser pulse. In this study, elemental spectra acquired using Laser-Induced Breakdown Spectroscopy (LIBS) technique were analysed to differentate between green coffee beans of arabica and robusta, which are collected from plantations in Malang, Bondowoso, Prigen, and Pasuruan. Results show that optimum conditions for acquiring spectra from green coffee beans using LIBS are at 120 mJ of laser energy and 1,0 μs of delay time. Green coffee beans of arabica and robusta contain some elements such as Ca, W, Sr, Mg, Be, Na, H, N, K, Rb, and O. Discriminant analysis method was then applied to distinguish the green beans of arabica and robusta coffee. Element identifiers of green coffee beans are Ca, W, Mg, Be, Na, and Sr. The abundant element in green coffee beans is Calcium (Ca), and depth-profile testing shows that Ca is homogeneous inside the beans.

  7. 用激光诱导击穿光谱技术定量分析土壤中Ba和Sr%Quantitative Analysis of Ba and Sr in Soil Using Laser-Induced Breakdown Spectroscopy

    Institute of Scientific and Technical Information of China (English)

    陈添兵; 姚明印; 刘木华; 雷泽剑; 彭秋梅; 徐媛; 张旭

    2012-01-01

    利用激光诱导击穿光谱(laser induced breakdown spectroscopy,LIBS)技术检测土壤标准样品中Ba和Sr的含量,用光纤光谱仪探测等离子体冷却过程中的发射谱线,选取BaⅡ455.41 nm和SrⅠ460.73 nm特征谱线为分析线.为了减小误差,采用Lorenizian函数进行光谱轮廓曲线拟合对数据预处理,提取光谱净强度值.选择多元素谱线强度和作为内标,根据分析线与内标线强度值之比建立定标曲线,Ba和Sr含量与其强度比的线性系数分别达到0.9900和0.9906,采用这种强度比定标法对Ba和Sr的含量进行反演,测定Ba和Sr含量值与标准值的相对偏差分别为5.7%和5.1%.%Laser induced breakdown spectroscopy (LIBS) was applied to measure barium and strontium elements in soil The emission spectrum was emitted as the plasma was cooling off, which was collected and analyzed by fiber spectrometer. Spectral lines of barium(BaII line at 455.41 nm) and strontium(Srl line at 460. 73 ran) were separately used for the determining. In order to reduce the error, fitting of the spectra by using Lorcnizian function was used, the datum was preprocessed and the net intensity value of the spectra was collected. A signal intensity in the proper range of the characteristic spectrum was chosen as the interior label. A calibration curve was drawn according to the ratio between the value of the analytical line and the interior scaling line. The correlation coefficient between the content and the intensity ratio of Ba and Sr were up to 0.990 0 and 0.990 6. The content of Ba and Sr was inversed by means of the intensity scaling method . As a result, the relative deviations between the content values and the standard values of Ba and Sr were 5. 7% and 5.1% respectively.

  8. Fusion related research with laser-induced-breakdown-spectroscopy on metallic samples at the ENEA-Frascati laboratory.

    Science.gov (United States)

    Almaviva, S.; Caneve, L.; Colao, F.; Maddaluno, G.

    2016-04-01

    The study of plasma-wall interactions is of paramount importance for continuous and fault free operations in thermonuclear fusion research to monitor the damages of plasma facing components (PFCs), plasma pollution from impurities and wall retention of hydrogen isotopes, like tritium. These needs make laser-induced-breakdown-spectroscopy (LIBS) a suitable candidate for a real time monitoring of PFCs in the current and next generation fusion devices, like ITER. It is also worthwhile for the quantitative analysis of surfaces, with micro-destructivity of the sample and depth profiling capabilities with sub-micrometric sensitivity. In this paper LIBS spectroscopy is exploited as a valid diagnostic tool for PFCs at the ENEA Research Center in Frascati (Italy) and at the Institute of Plasma Physics and Laser Microfusion (IPPLM) of Warsaw (Poland). The activities have been focused on LIBS characterization of samples simulating PFCs surfaces eroded/redeposited or contaminated from nuclear fuel after or during the normal operation of the reactor.

  9. Analysis of Metal Element Cr in Fresh Orange Leaf Using Laser-induced Breakdown Spectroscopy%激光诱导击穿光谱分析新鲜桔叶重金属元素铬

    Institute of Scientific and Technical Information of China (English)

    彭秋梅; 姚明印; 刘木华; 雷泽剑; 徐媛; 陈添兵

    2012-01-01

    To effectively employ LIBS technique in the field related to environmental pollution, primary experiments have been done in fresh orange leaf samples. Laser - induced breakdown spectroscopy (LIBS) is a burgeoning element analysis method. In the experiment, plasma in fresh orange leaf was induced using nanosecond Nd,YAG ( wavelength: 1 064 nm) laser as the excitation source in the atmospheric environment of the laboratory. The influence of the delay time and laser energy on spectral characteristics of element Cr in fresh plants was studied. Through evaluation of the signal-to-background ratio and Cr line intensity, the best delay time 1.6μs and the best laser energy 120 mJ were found. The calibration curve of element Cr was measured by studying the features of LIBS of element Cr in fresh plant under optimal conditions. The experimental results indicate that there is a good linear correlation between the element content 50 ~ 800 μg/mL and the relative intensity of spectral line. The experiment also shows that LIBS technology is a kind of fast effective means to detect metal elements in fresh plants.%为使激光诱导击穿光谱技术(LIBS)能实际应用于环境污染相关的领域,选择新鲜桔叶片样品作初步实验研究.该实验用纳秒级Nd:YAG激光器(波长:1064 nm)为光源,在实验室自然大气环境下诱导新鲜桔叶片产生等离子体,研究了延时时间和激光能量对新鲜桔叶片中铬元素激光诱导击穿光谱特性的影响,综合评价其信背比和信号强度得到了相应的最佳检测条件:最佳延时1.6 μs,最佳激光能量120 mJ.建立了Cr元素的定标曲线,并且定量分析了在最佳实验条件下样品中铬元素浓度.结果表明Cr元素浓度在50~ 800μg/mL范围内,Cr元素含量和光谱相对强度之间有较好的线性关系.实验也表明LIBS技术是一种快速检测新鲜植物叶片中重金属元素含量的有效工具.

  10. Signal enhancement in collinear double-pulse laser-induced breakdown spectroscopy applied to different soils

    Energy Technology Data Exchange (ETDEWEB)

    Nicolodelli, Gustavo, E-mail: gunicolodelli@hotmail.com [Embrapa Instrumentation, Rua XV de Novembro, 1452, CEP 13560-970 São Carlos, SP (Brazil); Senesi, Giorgio Saverio, E-mail: giorgio.senesi@imip.cnr.it [Institute of Inorganic Methodologies and Plasmas, CNR, Bari, 70126 Bari (Italy); Romano, Renan Arnon, E-mail: renan.romano@gmail.com [Embrapa Instrumentation, Rua XV de Novembro, 1452, CEP 13560-970 São Carlos, SP (Brazil); Physics Institute of São Carlos, University of São Paulo, IFSC-USP, Av. Trabalhador são-carlense, 400 Pq. Arnold Schimid, 13566-590 São Carlos, SP (Brazil); Oliveira Perazzoli, Ivan Luiz de, E-mail: ivanperazzoli@hotmail.com [Embrapa Instrumentation, Rua XV de Novembro, 1452, CEP 13560-970 São Carlos, SP (Brazil); Milori, Débora Marcondes Bastos Pereira, E-mail: debora.milori@embrapa.br [Embrapa Instrumentation, Rua XV de Novembro, 1452, CEP 13560-970 São Carlos, SP (Brazil)

    2015-09-01

    Laser-induced breakdown spectroscopy (LIBS) is a well-known consolidated analytical technique employed successfully for the qualitative and quantitative analysis of solid, liquid, gaseous and aerosol samples of very different nature and origin. Several techniques, such as dual-pulse excitation setup, have been used in order to improve LIBS's sensitivity. The purpose of this paper was to optimize the key parameters as excitation wavelength, delay time and interpulse, that influence the double pulse (DP) LIBS technique in the collinear beam geometry when applied to the analysis at atmospheric air pressure of soil samples of different origin and texture from extreme regions of Brazil. Additionally, a comparative study between conventional single pulse (SP) LIBS and DP LIBS was performed. An optimization of DP LIBS system, choosing the correct delay time between the two pulses, was performed allowing its use for different soil types and the use of different emission lines. In general, the collinear DP LIBS system improved the analytical performances of the technique by enhancing the intensity of emission lines of some elements up to about 5 times, when compared with conventional SP-LIBS, and reduced the continuum emission. Further, the IR laser provided the best performance in re-heating the plasma. - Highlights: • The correct choice of the delay time between the two pulses is crucial for the DP system. • An optimization of DP LIBS system was performed allowing its use for different soil and the use of different emission lines. • The DP LIBS system improved the analytical performances of the technique up to about 5 times, when compared with SP LIBS. • The IR laser provided the best performance in re-heating the plasma.

  11. Laser-Induced Breakdown Spectroscopy Technique in Identification of Ancient Ceramics Bodies and Glazes

    Science.gov (United States)

    Elsayed, Khaled; Imam, Hisham; Madkour, Fatma; Meheina, Galila; Gamal, Yosr

    2011-06-01

    In this paper we report a study on Laser Induced Breakdown Spectroscopy (LIBS) as a promising non-destructive technique for the identification of the colored glazes, and clay's bodies of Fatimid ceramics ancient artifacts. The scientific examination of ceramics may be helpful in unraveling the history of ancient shards, particularly as the process of its production such as firing condition and temperatures. The analysis of pottery, ceramic bodies and glazed coatings is required in order to structure the conservation or restoration of a piece. Revealing the technical skills of ancient potters has been one of the most important issues for gaining a deep insight of bygone culture and also it is required in order to structure the conservation or restoration of a piece of art. LIBS measurements were carried out by focusing a Nd-YAG laser at 1064 nm with pulse width of 10 ns and 50 mJ pulse energy on the surface of the sample by a 100-mm focal length lens. The plasma emission was collected by telescopic system and transferred through a fiber to Echelle spectrometer attached to an ICCD camera. The focal spot diameter is found to be in the range of 100-150 μm. which is small enough to consider this technique as a non-destructive technique. LIBS technique clarified that each piece of archaeological objects has its own finger print. X-ray diffraction (XRD) analysis was carried out on these archaeological ceramic body samples to study raw materials such as clays, which allowed the investigation of the crystal structure and showed the changes in its structure through firing process. This provided information on the ceramic characteristic and composition of the ceramic bodies.

  12. Nondestructive Determination of Cu Residue in Orange Peel by Laser Induced Breakdown Spectroscopy

    Science.gov (United States)

    Hu, Huiqin; Huang, Lin; Liu, Muhua; Chen, Tianbing; Yang, Ping; Yao, Mingyin

    2015-08-01

    Laser induced breakdown spectroscopy (LIBS) is an emerging tool with rapid, nondestructive, green characteristics in qualitative or quantitative analyses of composition in materials. But LIBS has its shortcomings in detect limit and sensitivity. In this work, heavy metal Cu in Gannan Navel Orange, which is one of famous fruits from Jiangxi of China, was analyzed. In view of LIBS's limit, it is difficult to determinate heavy metals in natural fruits. In this work, nine orange samples were pretreated in 50-500 μg/mL Cu solution, respectively. Another one orange sample was chosen as a control group without any pollution treatment. Previous researchers observed that the content of heavy metals is much higher in peel than in pulp. So, the content in pulp can be reflected by detecting peel. The real concentrations of Cu in peels were acquired by atomic absorption spectrophotometer (AAS). A calibration model of Cu I 324.7 and Cu I 327.4 was constructed between LIBS intensity and AAS concentration by six samples. The correlation coefficient of the two models is also 0.95. All of the samples were used to verify the accuracy of the model. The results show that the relative error (RE) between predicted and real concentration is less than 6.5%, and Cu I 324.7 line has smaller RE than Cu I 327.4. The analysis demonstrated that different characteristic lines decided different accuracy. The results prove the feasibility of detecting heavy metals in fruits by LIBS. But the results are limited in treated samples. The next work will focus on direct analysis of heavy metals in natural fruits without any pretreatment. This work is helpful to explore the distribution of heavy metals between pulp and peel. supported by National Natural Science Foundation of China (No. 31460419) and Major Project of Science and Technology of Jiangxi, China (No. 20143ACB21013)

  13. High-resolution three-dimensional compositional imaging by double-pulse laser-induced breakdown spectroscopy

    Science.gov (United States)

    Schiavo, C.; Menichetti, L.; Grifoni, E.; Legnaioli, S.; Lorenzetti, G.; Poggialini, F.; Pagnotta, S.; Palleschi, V.

    2016-08-01

    In this paper we present a new instrument specifically realized for high-resolution three-dimensional compositional analysis and mapping of materials. The instrument is based on the coupling of a Double-Pulse Laser-Induced Breakdown Spectroscopy (LIBS) instrument with an optical microscope. The compositional mapping of the samples is obtained by scanning the laser beam across the surface of the sample, while the in depth analysis is performed by sending multiple laser pulses on the same point. Depths of analysis of several tens of microns can be obtained. The instrument presented has definite advantages with respect to Laser Ablation-ICP Mass Spectrometry in many applications related to material analysis, biomedicine and environmental diagnostics. An application to the diagnostics of industrial ceramics is presented, demonstrating the feasibility of Double-Pulse LIBS Imaging and its advantages with respect to conventional single-pulse LIBS imaging.

  14. Application of laser induced breakdown spectroscopy (LIBS) instrumentation for international safeguards

    Energy Technology Data Exchange (ETDEWEB)

    Barefield Ii, James E [Los Alamos National Laboratory; Clegg, Samuel M [Los Alamos National Laboratory; Lopez, Leon N [Los Alamos National Laboratory; Le, Loan A [Los Alamos National Laboratory; Veirs, D Kirk [Los Alamos National Laboratory; Browne, Mike [Los Alamos National Laboratory

    2010-01-01

    Advanced methodologies and improvements to current measurements techniques are needed to strengthen the effectiveness and efficiency of international safeguards. This need was recognized and discussed at a Technical Meeting on 'The Application of Laser Spectrometry Techniques in IAEA Safeguards' held at IAEA headquarters (September 2006). One of the principal recommendations from that meeting was the need to pursue the development of novel complementary access instrumentation based on Laser Induced Breakdown Spectroscopy (UBS) for the detection of gaseous and solid signatures and indicators of nuclear fuel cycle processes and associated materials'. Pursuant to this recommendation the Department of Safeguards (SG) under the Division of Technical Support (SGTS) convened the 'Experts and Users Advisory Meeting on Laser Induced Breakdown Spectroscopy (LIBS) for Safeguards Applications' also held at IAEA headquarters (July 2008). This meeting was attended by 12 LlBS experts from the Czech Republic, the European Commission, France, the Republic of South Korea, the United States of America, Germany, the United Kingdom of Great Britain, Canada, and Northern Ireland. Following a presentation of the needs of the IAEA inspectors, the LIBS experts agreed that needs as presented could be partially or fully fulfilled using LIBS instrumentation. Inspectors needs were grouped into the following broad categories: (1) Improvements to in-field measurements/environmental sampling; (2) Monitoring status of activities in Hot Cells; (3) Verify status of activity at a declared facility via process monitoring; and (4) Need for pre-screening of environmental samples before analysis. The primary tool employed by the IAEA to detect undeclared processes and activities at special nuclear material facilities and sites is environmental sampling. One of the objectives of the Next Generation Safeguards Initiative (NGSI) Program Plan calls for the development of advanced

  15. Non-gated laser-induced breakdown spectroscopy in bulk water by position-selective detection

    Energy Technology Data Exchange (ETDEWEB)

    Tian, Ye; Xue, Boyang; Song, Jiaojian; Lu, Yuan; Zheng, Ronger, E-mail: rzheng@ouc.edu.cn [Optics and Optoelectronics Laboratory, Ocean University of China, Qingdao 266100 (China)

    2015-09-14

    Temporal and spatial evolutions of the laser-induced plasma in bulk water are investigated using fast imaging and emission spectroscopic techniques. By tightly focusing a single-pulse nanosecond Nd: YAG laser beam into the bulk water, we generate a strongly expanded plasma with high reproducibility. Such a strong expanding plasma enables us to obtain well-resolved spectral lines by means of position-selective detection; hence, the time-gated detector becomes abdicable. The present results suggest not only a possible non-gated approach for underwater laser-induced breakdown spectroscopy but also give an insight into the plasma generation and expansion in bulk water.

  16. Double-pulse standoff laser-induced breakdown spectroscopy for versatile hazardous materials detection

    Energy Technology Data Exchange (ETDEWEB)

    Gottfried, Jennifer L. [U.S. Army Research Laboratory, AMSRD-ARL-WM-BD, Aberdeen Proving Ground, MD, 21005-5069 (United States)], E-mail: jennifer.gottfried@arl.army.mil; De Lucia, Frank C.; Munson, Chase A.; Miziolek, Andrzej W. [U.S. Army Research Laboratory, AMSRD-ARL-WM-BD, Aberdeen Proving Ground, MD, 21005-5069 (United States)

    2007-12-15

    We have developed a double-pulse standoff laser-induced breakdown spectroscopy (ST-LIBS) system capable of detecting a variety of hazardous materials at tens of meters. The use of a double-pulse laser improves the sensitivity and selectivity of ST-LIBS, especially for the detection of energetic materials. In addition to various metallic and plastic materials, the system has been used to detect bulk explosives RDX and Composition-B, explosive residues, biological species such as the anthrax surrogate Bacillus subtilis, and chemical warfare simulants at 20 m. We have also demonstrated the discrimination of explosive residues from various interferents on an aluminum substrate.

  17. Laser-induced breakdown spectroscopy at high temperatures in industrial boilers and furnaces.

    Science.gov (United States)

    Blevins, Linda G; Shaddix, Christopher R; Sickafoose, Shane M; Walsh, Peter M

    2003-10-20

    Laser-induced breakdown spectroscopy (LIBS) was applied (1) near the superheater of an electric power generation boiler burning biomass, coal, or both; (2) at the exit of a glass-melting furnace burning natural gas and oxygen; and (3) near the nose arches of two paper mill recovery boilers burning black liquor. Difficulties associated with the high temperatures and high particle loadings in these environments were surmounted by use of novel LIBS probes. Echelle and linear spectrometers coupled to intensified CCD cameras were used individually and sometimes simultaneously. Elements detected include Na, K, Ca, Mg, C, B, Si, Mn, Al, Fe, Rb, Cl, and Ti.

  18. Femtosecond Laser-Induced Breakdown Spectroscopy for Detection of Trace Elements in Sophora Leaves

    Institute of Scientific and Technical Information of China (English)

    Myriam Bossu; HAO Zuo-Qiang; Matthieu Baudelet; YU Jia; ZHANG Zhe; ZHANG Jie

    2007-01-01

    Sophora leaves from several areas in Beijing are analysed by femtoeecond laser-induced breakdown spectroscopy (femto-LIBS).AIthough the used spectral detection systemis not time-resolved,thespectral lines of trace mineral elements are detected and anallyed.It is proven that the femto-LIBS can be an effcient method to detect mineral trace elements contained in tree leaves which is a biomonitor for atmospheric pollution assessment or botanic studies.An interesting case of correlation between trace elements detected in tree leaves and the pollution of the concerned area is presented,for the first time to our knowledge.

  19. Remote Raman - laser induced breakdown spectroscopy (LIBS) geochemical investigation under Venus atmospheric conditions

    Energy Technology Data Exchange (ETDEWEB)

    Clegg, Sanuel M [Los Alamos National Laboratory; Barefield, James E [Los Alamos National Laboratory; Humphries, Seth D [Los Alamos National Laboratory; Wiens, Roger C [Los Alamos National Laboratory; Vaniman, D. T. [Los Alamos National Laboratory; Sharma, S. K. [UNIV OF HAWAII; Misra, A. K. [UNIV OF HAWAII; Dyar, M. D. [MT. HOLYOKE COLLEGE; Smrekar, S. E. [JET PROPULSION LAB.

    2010-12-13

    The extreme Venus surface temperatures ({approx}740 K) and atmospheric pressures ({approx}93 atm) create a challenging environment for surface missions. Scientific investigations capable of Venus geochemical observations must be completed within hours of landing before the lander will be overcome by the harsh atmosphere. A combined remote Raman - LIBS (Laser Induced Breakdown Spectroscopy) instrument is capable of accomplishing the geochemical science goals without the risks associated with collecting samples and bringing them into the lander. Wiens et al. and Sharma et al. demonstrated that both analytical techniques can be integrated into a single instrument capable of planetary missions. The focus of this paper is to explore the capability to probe geologic samples with Raman - LIBS and demonstrate quantitative analysis under Venus surface conditions. Raman and LIBS are highly complementary analytical techniques capable of detecting both the mineralogical and geochemical composition of Venus surface materials. These techniques have the potential to profoundly increase our knowledge of the Venus surface composition, which is currently limited to geochemical data from Soviet Venera and VEGA landers that collectively suggest a surface composition that is primarily tholeiitic basaltic with some potentially more evolved compositions and, in some locations, K-rich trachyandesite. These landers were not equipped to probe the surface mineralogy as can be accomplished with Raman spectroscopy. Based on the observed compositional differences and recognizing the imprecise nature of the existing data, 15 samples were chosen to constitute a Venus-analog suite for this study, including five basalts, two each of andesites, dacites, and sulfates, and single samples of a foidite, trachyandesite, rhyolite, and basaltic trachyandesite under Venus conditions. LIBS data reduction involved generating a partial least squares (PLS) model with a subset of the rock powder standards to

  20. Forensic application of laser-induced breakdown spectroscopy for the discrimination of questioned documents.

    Science.gov (United States)

    Lennard, Chris; El-Deftar, Moteaa M; Robertson, James

    2015-09-01

    Document examination is an important forensic discipline and the legal system regularly needs the knowledge and skills of the scientific expert when questioned documents are involved in criminal or civil matters. Amongst the many aspects of the scientific examination of documents, elemental analysis can provide useful results. In this study, the evaluation of the analytical performance of a commercially available laser-induced breakdown spectroscopy (LIBS) instrument was conducted on office papers, writing inks, inkjet inks and laser printer toners. The paper sample set analysed consisted of 33 Australian paper specimens originating from the same production plant but representing different brands and/or batches. In addition, a total of 131 ink or toner samples were examined that included black and blue ballpoint inks, black inkjet inks, and black laser printer toners originating from several manufacturing sources, models and/or batches. Results from the LIBS method were compared against those obtained using more established elemental profiling method such as laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). LIBS demonstrated detectable and significant differences between different batches of the same brand as well as between different brands of paper, ink and toner samples. The LIBS method provided comparable discrimination powers for the selected sample sets when compared to those obtained using LA-ICP-MS (discrimination from 99.8 and 100% of the sample pairs, depending on the sample subset under examination). LIBS is a suitable technique for the determination of elemental composition as part of a protocol for the examination of questioned documents.

  1. Laser-induced optical breakdown spectroscopy of polymer materials based on evaluation of molecular emission bands

    Science.gov (United States)

    Trautner, Stefan; Jasik, Juraj; Parigger, Christian G.; Pedarnig, Johannes D.; Spendelhofer, Wolfgang; Lackner, Johannes; Veis, Pavel; Heitz, Johannes

    2017-03-01

    Laser-induced breakdown spectroscopy (LIBS) for composition analysis of polymer materials results in optical spectra containing atomic and ionic emission lines as well as molecular emission bands. In the present work, the molecular bands are analyzed to obtain spectroscopic information about the plasma state in an effort to quantify the content of different elements in the polymers. Polyethylene (PE) and a rubber material from tire production are investigated employing 157 nm F2 laser and 532 nm Nd:YAG laser ablation in nitrogen and argon gas background or in air. The optical detection reaches from ultraviolet (UV) over the visible (VIS) to the near infrared (NIR) spectral range. In the UV/VIS range, intense molecular emissions, C2 Swan and CN violet bands, are measured with an Echelle spectrometer equipped with an intensified CCD camera. The measured molecular emission spectra can be fitted by vibrational-rotational transitions by open access programs and data sets with good agreement between measured and fitted spectra. The fits allow determining vibrational-rotational temperatures. A comparison to electronic temperatures Te derived earlier from atomic carbon vacuum-UV (VUV) emission lines show differences, which can be related to different locations of the atomic and molecular species in the expanding plasma plume. In the NIR spectral region, we also observe the CN red bands with a conventional CDD Czerny Turner spectrometer. The emission of the three strong atomic sulfur lines between 920 and 925 nm is overlapped by these bands. Fitting of the CN red bands allows a separation of both spectral contributions. This makes a quantitative evaluation of sulfur contents in the start material in the order of 1 wt% feasible.

  2. Application of Laser Induced Breakdown Spectroscopy to the identification of emeralds from different synthetic processes

    Energy Technology Data Exchange (ETDEWEB)

    Agrosì, G. [Department of Scienze della Terra e Geoambientali, University of Bari, Bari (Italy); Tempesta, G., E-mail: gioacchino.tempesta@uniba.it [Department of Scienze della Terra e Geoambientali, University of Bari, Bari (Italy); Scandale, E. [Department of Scienze della Terra e Geoambientali, University of Bari, Bari (Italy); Legnaioli, S.; Lorenzetti, G.; Pagnotta, S.; Palleschi, V. [Institute of Chemistry of Organometallic Compounds, CNR, Pisa (Italy); Mangone, A. [Department of Chemistry, University of Bari, Bari (Italy); Lezzerini, M. [Department of Earth Sciences, University of Pisa, Pisa (Italy)

    2014-12-01

    Laser Induced Breakdown Spectroscopy can provide a useful contribution in mineralogical field in which the quantitative chemical analyses (including the evaluation of light elements) can play a key role in the studies on the origin of the emeralds. In particular, the chemical analyses permit to determine those trace elements, known as fingerprints, that can be useful to study their provenance. This technique, not requiring sample preparation results particularly suitable for gemstones, that obviously must be studied in a non-destructive way. In this paper, the LIBS technique was applied to distinguish synthetic emeralds grown by Biron hydrothermal method from those grown by Chatham flux method. The analyses performed by collinear double-pulse LIBS give a signal enhancement useful for the quantitative chemical analyses while guaranteeing a minimal sample damage. In this way it was obtained a considerable improvement on the detection limit of the trace elements, whose determination is essential for determining the origin of emerald gemstone. The trace elements V, Cr, and Fe and their relative amounts allowed the correct attribution of the manufacturer. Two different methods for quantitative analyses were used for this study: the standard Calibration-Free LIBS (CF-LIBS) method and its recent evolution, the One Point Calibration LIBS (OPC-LIBS). This is the first approach to the evaluation of the emerald origin by means of the LIBS technique. - Highlights: • A LIBS method for discrimination between synthetic emeralds is presented. • Only one standard of known composition is needed for the analysis. • A set of two kind of synthetic emeralds has been analyzed. • The cromophoric elements Cr, V and Fe amounts have been used to determine the origin of emerald gemstone.

  3. Laser-induced breakdown spectroscopy: Extending its application to soil pH measurements

    Science.gov (United States)

    Ferreira, Edilene Cristina; Gomes Neto, José A.; Milori, Débora M. B. P.; Ferreira, Ednaldo José; Anzano, Jesús Manuel

    2015-08-01

    Acid-base equilibria are involved in almost all the processes that occur in soil. The bioavailability of nutrients for plants, for instance, depends on the solubilization of mineral nutrients in the soil solution, which is a pH-dependent process. The determination of pH in soil solutions is usually carried out by potentiometry using a glass membrane electrode, after extracting some of the soil components with water or CaCl2 solution. The present work describes a simple method for determining the pH of soil, using laser-induced breakdown spectroscopy (LIBS). Sixty samples presenting different textural composition and pH (previously determined by potentiometry) were employed. The samples were divided into a calibration set with fifty samples and a validation set with ten samples. LIBS spectra were recorded for each pelleted sample using laser pulse energy of 115 mJ. The intensities of thirty-two emission lines for Al, Ca, H, and O were used to fit a partial least squares (PLS) model. The model was validated by prediction of the pH of the validation set samples, which showed good agreement with the reference values. The prediction mean absolute error was 0.3 pH units and the root mean square error of the prediction was 0.4. These results highlight the potential of LIBS for use in other applications beyond elemental composition determinations. For soil analysis, the proposed method offers the possibility of determining pH, in addition to nutrients and contaminants, using a single LIBS measurement.

  4. Trace element quantification of lead based roof sheets of historical monuments by Laser Induced Breakdown Spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Syvilay, D., E-mail: delphine.syvilay@culture.gouv.fr [LRMH USR 3224, 29 rue de Paris, 77420 Champs-sur-Marne (France); Texier, A. [LRMH USR 3224, 29 rue de Paris, 77420 Champs-sur-Marne (France); Arles, A.; Gratuze, B. [IRAMAT, 3D, rue de la Férollerie, 45071 Orléans Cedex 2 (France); Wilkie-Chancellier, N.; Martinez, L.; Serfaty, S. [SATIE, UMR CNRS 8029, Université de Cergy-Pontoise, ENS Cachan, 95000 Cergy-Pontoise Cedex (France); Detalle, V. [LRMH USR 3224, 29 rue de Paris, 77420 Champs-sur-Marne (France)

    2015-01-01

    The aim of this paper is to identify the different periods of construction or restoration of the lead roof of a historic monument. Trace elements in a lead matrix can be a signature of the metallurgical processes, allowing identification of a specific time period for the production of the lead used to build the roof. The ability of LIBS (Laser Induced Breakdown Spectroscopy) to detect such trace elements in a lead matrix is therefore explored and checked by comparing its results with LA-ICP-MS as a reference method (Laser Ablation-Inductively Coupled Plasma-Mass Spectrometry). Concentrations of 263 samples were compared between LIBS and LA-ICP-MS data and their correlation was evaluated. Another way to compare their results is also suggested by combining PCA (Principal Component Analysis) and GIS (Geographic Information System). As a result statistical mappings were created, highlighting metallurgical groups of samples across the roof of the building. This innovative approach links concentration and spatial location resulting in an easily interpretable graphical presentation of the data. The results of both spectrometry methods lead to similar conclusions with distinctive areas of different lead compositions and by extension different lead dating across the roof. But since LIBS is portable we can conclude that it is a suitable and reliable instrument for in-situ applications on historic monuments. - Highlights: • Quantification of trace elements (Ag, Bi, Cu and Sn) in a lead matrix by LIBS and LA-ICP-MS • Low limit of detection for Ag, Bi, Cu and Sn by using LIBS portable instrumentation • Set up a specific data processing combining PCA and GIS for cultural heritage application • Comparison of LIBS and LA-ICP-MS results with 263 samples • 488 samples analyzed by LIBS.

  5. Hydrogen isotope detection in metal matrix using double-pulse laser-induced breakdown-spectroscopy

    Science.gov (United States)

    Fantoni, Roberta; Almaviva, Salvatore; Caneve, Luisa; Colao, Francesco; Maddaluno, Giorgio; Gasior, Pawel; Kubkowska, Monika

    2017-03-01

    The amount of hydrogen isotopes retained in plasma facing components (PFCs) and the determination of their surface layer composition are among the most critical issues for the next generation fusion device, ITER, under construction in Cadarache (France). Laser Induced Breakdown Spectroscopy (LIBS) is currently under evaluation as a technique suitable for quantitative, in situ, non-invasive measurements of these quantities. In order to detect traces of contaminant in metallic samples and improve its limit of detection (LOD), the Double Pulse LIBS (DP-LIBS) variant can be used instead of the standard Single Pulse LIBS (SP-LIBS), as it has been proven by several authors that DP-LIBS can considerably raise the analytical performances of the technique. In this work Mo samples coated with a 1.5-1.8 μm thick W-Al mixed layer, contaminated with co-deposited deuterium (D) were measured by SP- and DP-LIBS under vacuum (p 5 × 10- 5 mbar), with an experimental set-up simulating conditions that can be found in a real fusion device between plasma discharges. A partial Calibration Free procedure (pCF) was applied to the LIBS data in order to retrieve the relative concentration of W and Al in the mixed layer. The amount of deuterium was then inferred by using tungsten as internal standard, accounting for the intensity ratio between the Dα line and nearby W I lines. The results are in satisfactory agreement with those obtained from preliminary Ion Beam Analysis measurements performed immediately after the specimen's realization.

  6. Detection of visually unrecognizable braking tracks using Laser-Induced Breakdown Spectroscopy, a feasibility study

    Science.gov (United States)

    Prochazka, David; Bilík, Martin; Prochazková, Petra; Brada, Michal; Klus, Jakub; Pořízka, Pavel; Novotný, Jan; Novotný, Karel; Ticová, Barbora; Bradáč, Albert; Semela, Marek; Kaiser, Jozef

    2016-04-01

    Identification of the position, length and mainly beginning of a braking track has proven to be essential for determination of causes of a road traffic accident. With the introduction of modern safety braking systems and assistance systems such as the Anti-lock Braking System (ABS) or Electronic Stability Control (ESC), the visual identification of braking tracks that has been used up until the present is proving to be rather complicated or even impossible. This paper focuses on identification of braking tracks using a spectrochemical analysis of the road surface. Laser-Induced Breakdown Spectroscopy (LIBS) was selected as a method suitable for fast in-situ element detection. In the course of detailed observations of braking tracks it was determined that they consist of small particles of tire treads that are caught in intrusions in the road surface. As regards detection of the "dust" resulting from wear and tear of tire treads in the environment, organic zinc was selected as the identification element in the past. The content of zinc in tire treads has been seen to differ with regard to various sources and tire types; however, the arithmetic mean and modus of these values are approximately 1% by weight. For in-situ measurements of actual braking tracks a mobile LIBS device equipped with a special module was used. Several measurements were performed for 3 different cars and tire types respectively which slowed down with full braking power. Moreover, the influence of different initial speed, vehicle mass and braking track length on detected signal is discussed here.

  7. Elemental content of enamel and dentin after bleaching of teeth (a comparative study between laser-induced breakdown spectroscopy and x-ray photoelectron spectroscopy)

    Energy Technology Data Exchange (ETDEWEB)

    Imam, H. [National Institute of Laser Enhanced Sciences, NILES, Cairo University, Giza (Egypt); Ahmed, Doaa [Department of Restorative Sciences, Faculty of Dentistry, Alexandria University, Alexandria (Egypt); Eldakrouri, Ashraf [National Institute of Laser Enhanced Sciences, NILES, Cairo University, Giza (Egypt); Department of Optometry and Vision Science, College of Applied Medical Science, King Saud University, Riyadh (Saudi Arabia)

    2013-06-21

    The elemental content of the superficial and inner enamel as well as that of dentin was analyzed using laser-induced breakdown spectroscopy (LIBS) and x-ray photoelectron spectroscopy (XPS) of bleached and unbleached tooth specimens. It is thus clear from the spectral analysis using both the LIBS and XPS technique that elemental changes (though insignificant within the scopes of this study) of variable intensities do occur on the surface of the enamel and extend deeper to reach dentin. The results of the LIBS revealed a slight reduction in the calcium levels in the bleached compared to the control specimens in all the different bleaching groups and in both enamel and dentin. The good correlation found between the LIBS and XPS results demonstrates the possibility of LIBS technique for detection of minor loss in calcium and phosphorus in enamel and dentin.

  8. Isotopic determination of uranium in soil by laser induced breakdown spectroscopy

    Science.gov (United States)

    Chan, George C.-Y.; Choi, Inhee; Mao, Xianglei; Zorba, Vassilia; Lam, Oanh P.; Shuh, David K.; Russo, Richard E.

    2016-08-01

    Laser-induced breakdown spectroscopy (LIBS) operated under ambient pressure has been evaluated for isotopic analysis of uranium in real-world samples such as soil, with U concentrations in the single digit percentage levels. The study addresses the requirements for spectral decomposition of 235U and 238U atomic emission peaks that are only partially resolved. Although non-linear least-square fitting algorithms are typically able to locate the optimal combination of fitting parameters that best describes the experimental spectrum even when all fitting parameters are treated as free independent variables, the analytical results of such an unconstrained free-parameter approach are ambiguous. In this work, five spectral decomposition algorithms were examined, with different known physical properties (e.g., isotopic splitting, hyperfine structure) of the spectral lines sequentially incorporated into the candidate algorithms as constraints. It was found that incorporation of such spectral-line constraints into the decomposition algorithm is essential for the best isotopic analysis. The isotopic abundance of 235U was determined from a simple two-component Lorentzian fit on the U II 424.437 nm spectral profile. For six replicate measurements, each with only fifteen laser shots, on a soil sample with U concentration at 1.1% w/w, the determined 235U isotopic abundance was (64.6 ± 4.8)%, and agreed well with the certified value of 64.4%. Another studied U line - U I 682.691 nm possesses hyperfine structure that is comparatively broad and at a significant fraction as the isotopic shift. Thus, 235U isotopic analysis with this U I line was performed with spectral decomposition involving individual hyperfine components. For the soil sample with 1.1% w/w U, the determined 235U isotopic abundance was (60.9 ± 2.0)%, which exhibited a relative bias about 6% from the certified value. The bias was attributed to the spectral resolution of our measurement system - the measured line

  9. Simultaneous laser induced breakdown spectroscopy and Pd-assisted methane decomposition at different pressures

    Energy Technology Data Exchange (ETDEWEB)

    Reyhani, A. [Phys. Dept., Faculty of Science, Imam Khomeini International University, Qazvin, 34149-16818 (Iran, Islamic Republic of); Mortazavi, S.Z. [Phys. Dept., Amirkabir University of Technology, P.O. Box 15875-4413, Tehran (Iran, Islamic Republic of); Parvin, P., E-mail: parvin@aut.ac.ir [Phys. Dept., Amirkabir University of Technology, P.O. Box 15875-4413, Tehran (Iran, Islamic Republic of); Mahmoudi, Z. [Phys. Dept., Amirkabir University of Technology, P.O. Box 15875-4413, Tehran (Iran, Islamic Republic of)

    2012-08-15

    Methane decomposition is investigated during Pd-assisted laser induced plasma in the controlled chamber at various pressures using Q-switched Nd:YAG laser. Real time LIBS monitoring is applied to reveal the involved mechanisms during methane decomposition by inspecting the plasma parameters at mano-metric pressures of 1 to 10 mbar. The dependence of electron density and plasma temperature with pressure is also studied. It is shown that the plasma recreates higher hydrocarbons during the decomposition of methane. In addition, Fourier transform infrared spectroscopy, gas chromatography, scanning electron microscopy and transmission electron microscopy are applied to support the findings. - Highlights: Black-Right-Pointing-Pointer Simultaneous laser induced breakdown spectroscopy Black-Right-Pointing-Pointer Pd-assisted methane decomposition Black-Right-Pointing-Pointer Nanosecond pulsed laser decomposition of methane Black-Right-Pointing-Pointer Generation of higher hydrocarbon Black-Right-Pointing-Pointer Dependence of electron density and temperature of induced plasma with pressure.

  10. Detecting salt deposition on a wind turbine blade using laser induced breakdown spectroscopy technique

    Science.gov (United States)

    Sathiesh Kumar, V.; Vasa, Nilesh J.; Sarathi, R.

    2013-07-01

    The study of pollution performance on a wind turbine blade due to lightning is important, as it can cause major damage to wind turbine blades. In the present work, optical emission spectroscopy (OES) technique is used to understand the influence of pollutant deposited on a wind turbine blade in an off-shore environment. A methodical experimental study was carried out by adopting IEC 60507 standards, and it was observed that the lightning discharge propagates at the interface between the pollutant and the glass fiber reinforced plastic (Material used in manufacturing of wind turbine blades). In addition, as a diagnostic condition monitoring technique, laser-induced breakdown spectroscopy (LIBS) is proposed and demonstrated to rank the severity of pollutant on the wind turbine blades from a remote area. Optical emission spectra observed during surface discharge process induced by lightning impulse voltage is in agreement with the spectra observed during LIBS.

  11. Evaluation of the laser-induced breakdown spectroscopy technique for determination of the chemical composition of copper concentrates

    Energy Technology Data Exchange (ETDEWEB)

    Łazarek, Łukasz, E-mail: lukasz.lazarek@pwr.wroc.pl [Laser and Fiber Electronics Group, Faculty of Electronics, Wroclaw University of Technology, Wyb. Wyspianskiego 27, 50-370 Wroclaw (Poland); Antończak, Arkadiusz J.; Wójcik, Michał R. [Laser and Fiber Electronics Group, Faculty of Electronics, Wroclaw University of Technology, Wyb. Wyspianskiego 27, 50-370 Wroclaw (Poland); Drzymała, Jan [Faculty of Geoengineering, Mining and Geology, Wroclaw University of Technology, Wyb. Wyspianskiego 27, 50-370 Wroclaw (Poland); Abramski, Krzysztof M. [Laser and Fiber Electronics Group, Faculty of Electronics, Wroclaw University of Technology, Wyb. Wyspianskiego 27, 50-370 Wroclaw (Poland)

    2014-07-01

    Laser-induced breakdown spectroscopy (LIBS), like many other spectroscopic techniques, is a comparative method. Typically, in qualitative analysis, synthetic certified standard with a well-known elemental composition is used to calibrate the system. Nevertheless, in all laser-induced techniques, such calibration can affect the accuracy through differences in the overall composition of the chosen standard. There are also some intermediate factors, which can cause imprecision in measurements, such as optical absorption, surface structure and thermal conductivity. In this work the calibration performed for the LIBS technique utilizes pellets made directly from the tested materials (old well-characterized samples). This choice produces a considerable improvement in the accuracy of the method. This technique was adopted for the determination of trace elements in industrial copper concentrates, standardized by conventional atomic absorption spectroscopy with a flame atomizer. A series of copper flotation concentrate samples was analyzed for three elements: silver, cobalt and vanadium. We also proposed a method of post-processing the measurement data to minimize matrix effects and permit reliable analysis. It has been shown that the described technique can be used in qualitative and quantitative analyses of complex inorganic materials, such as copper flotation concentrates. It was noted that the final validation of such methodology is limited mainly by the accuracy of the characterization of the standards. - Highlights: • A laser-induced breakdown spectroscopy technique is introduced for composition monitoring in industrial copper concentrates. • Calibration samples consisted of pellets produced from the tested materials. • The proposed method of post-processing significantly minimizes matrix effects. • The possible uses of this technique are limited mainly by accurate characterization of the standard samples.

  12. Determination of silicon in plant materials by laser-induced breakdown spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Souza, Paulino Florêncio de [Centro de Energia Nuclear na Agricultura, Universidade de São Paulo, Av. Centenário 303, 13416-000, Piracicaba, SP (Brazil); Centro de Tecnologia Canavieira, PO Box 162, 13400-970 Piracicaba, SP (Brazil); Santos, Dário [Departamento de Ciências Exatas e da Terra, Universidade Federal de São Paulo, Rua Prof. Artur Riedel, 275, 09972-270, Diadema, SP (Brazil); Gustinelli Arantes de Carvalho, Gabriel; Nunes, Lidiane Cristina [Centro de Energia Nuclear na Agricultura, Universidade de São Paulo, Av. Centenário 303, 13416-000, Piracicaba, SP (Brazil); Silva Gomes, Marcos da [Centro de Energia Nuclear na Agricultura, Universidade de São Paulo, Av. Centenário 303, 13416-000, Piracicaba, SP (Brazil); Departamento de Química, Universidade Federal de São Carlos, 13565-905 São Carlos, SP (Brazil); Guerra, Marcelo Braga Bueno [Centro de Energia Nuclear na Agricultura, Universidade de São Paulo, Av. Centenário 303, 13416-000, Piracicaba, SP (Brazil); Krug, Francisco José, E-mail: fjkrug@cena.usp.br [Centro de Energia Nuclear na Agricultura, Universidade de São Paulo, Av. Centenário 303, 13416-000, Piracicaba, SP (Brazil)

    2013-05-01

    In spite of the importance of Si for improving the productivity of many important crops, such as those from the Poaceae family (e.g. sugar cane, maize, wheat, rice), its quantitative determination in plants is seldom carried out and restricted to few laboratories in the world. There is a survey of methods in the literature, but most of them are either laborious or difficult to validate in view of the low availability of reference materials with a certified Si mass fraction. The aim of this study is to propose a method for the direct determination of Si in pellets of plant materials by laser-induced breakdown spectroscopy (LIBS). The experimental setup was designed by using a Q-switched Nd:YAG laser at 1064 nm (5 ns, 10 Hz) and the emission signals were collected by lenses into an optical fiber coupled to an Echelle spectrometer equipped with an intensified charge-coupled device. Experiments were carried out with leaves from 24 sugar cane varieties, with mass fractions varying from ca. 2 to 10 g kg{sup −1} Si. Pellets prepared from cryogenically ground leaves were used as test samples for both method development and validation of the calibration model. Best results were obtained when the test samples were interrogated with laser fluence of 50 J cm{sup −2} (750 μm spot size) and measurements carried out at Si I 212.412 nm emission line. The results obtained by LIBS were compared with those from inductively coupled plasma optical emission spectrometry after oven-induced alkaline digestion, and no significant differences were observed after applying the Student's t-test at 95% confidence level. The trueness of the proposed LIBS method was also confirmed from the analysis of CRM GBW 07603 (Bush branches and leaves). - Highlights: • This is the first application of LIBS for determination of Si in plant materials. • Data indicate that the method is appropriate for Si diagnosis in routine analysis. • Silicon can be simultaneously determined with macro- and

  13. Comparison of baseline removal methods for laser-induced breakdown spectroscopy of geological samples

    Science.gov (United States)

    Dyar, M. Darby; Giguere, Stephen; Carey, CJ; Boucher, Thomas

    2016-12-01

    This project examines the causes, effects, and optimization of continuum removal in laser-induced breakdown spectroscopy (LIBS) to produce the best possible prediction accuracy of elemental composition in geological samples. We compare prediction accuracy resulting from several different techniques for baseline removal, including asymmetric least squares (ALS), adaptive iteratively reweighted penalized least squares (Air-PLS), fully automatic baseline correction (FABC), continuous wavelet transformation, median filtering, polynomial fitting, the iterative thresholding Dietrich method, convex hull/rubber band techniques, and a newly-developed technique for Custom baseline removal (BLR). We assess the predictive performance of these methods using partial least-squares analysis for 13 elements of geological interest, expressed as the weight percentages of SiO2, Al2O3, TiO2, FeO, MgO, CaO, Na2O, K2O, and the parts per million concentrations of Ni, Cr, Zn, Mn, and Co. We find that previously published methods for baseline subtraction generally produce equivalent prediction accuracies for major elements. When those pre-existing methods are used, automated optimization of their adjustable parameters is always necessary to wring the best predictive accuracy out of a data set; ideally, it should be done for each individual variable. The new technique of Custom BLR produces significant improvements in prediction accuracy over existing methods across varying geological data sets, instruments, and varying analytical conditions. These results also demonstrate the dual objectives of the continuum removal problem: removing a smooth underlying signal to fit individual peaks (univariate analysis) versus using feature selection to select only those channels that contribute to best prediction accuracy for multivariate analyses. Overall, the current practice of using generalized, one-method-fits-all-spectra baseline removal results in poorer predictive performance for all methods. The

  14. Laser-induced breakdown spectroscopy: Extending its application to soil pH measurements

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, Edilene Cristina, E-mail: edilene@iq.unesp.br [São Paulo State University – UNESP, Analytical Chemistry Department, Rua Prof. Francisco Degni 55, CEP 14800-060, Araraquara, SP (Brazil); Gomes Neto, José A. [São Paulo State University – UNESP, Analytical Chemistry Department, Rua Prof. Francisco Degni 55, CEP 14800-060, Araraquara, SP (Brazil); Milori, Débora M.B.P.; Ferreira, Ednaldo José [Embrapa Agricultural Instrumentation, Rua XV de Novembro 1452, CEP 13560-970, São Carlos, SP (Brazil); Anzano, Jesús Manuel [Laser Laboratory & Environment, Faculty of Sciences, University of Zaragoza, C/. Pedro Cerbuna 12, 50009, Zaragoza (Spain)

    2015-08-01

    Acid–base equilibria are involved in almost all the processes that occur in soil. The bioavailability of nutrients for plants, for instance, depends on the solubilization of mineral nutrients in the soil solution, which is a pH-dependent process. The determination of pH in soil solutions is usually carried out by potentiometry using a glass membrane electrode, after extracting some of the soil components with water or CaCl{sub 2} solution. The present work describes a simple method for determining the pH of soil, using laser-induced breakdown spectroscopy (LIBS). Sixty samples presenting different textural composition and pH (previously determined by potentiometry) were employed. The samples were divided into a calibration set with fifty samples and a validation set with ten samples. LIBS spectra were recorded for each pelleted sample using laser pulse energy of 115 mJ. The intensities of thirty-two emission lines for Al, Ca, H, and O were used to fit a partial least squares (PLS) model. The model was validated by prediction of the pH of the validation set samples, which showed good agreement with the reference values. The prediction mean absolute error was 0.3 pH units and the root mean square error of the prediction was 0.4. These results highlight the potential of LIBS for use in other applications beyond elemental composition determinations. For soil analysis, the proposed method offers the possibility of determining pH, in addition to nutrients and contaminants, using a single LIBS measurement. - Highlights: • Physical, chemical, and biological properties of soil are influenced by pH. • The pH of mineral soils is normally determined in slurries of water and soil sample by potentiometric measurements. • The association of LIBS elemental emissions with multivariate strategies of analysis has become LIBS a powerful technique. • LIBS was unprecedentedly applied for direct pH determination in different kinds of soil sample. • The clean and fast proposed

  15. Can the provenance of the conflict minerals columbite and tantalite be ascertained by laser-induced breakdown spectroscopy?

    Science.gov (United States)

    Harmon, Russell S; Shughrue, Katrina M; Remus, Jeremiah J; Wise, Michael A; East, Lucille J; Hark, Richard R

    2011-07-01

    Conflict minerals is a term applied to ores mined in conditions of armed conflict and human rights abuse. Niobium and tantalum are two rare metals whose primary natural occurrence is in the complex oxide minerals columbite and tantalite, the ore of which is commonly referred to as coltan. The illicit export of coltan ore from the Democratic Republic of the Congo is thought to be responsible for financing the ongoing civil conflicts in this region. Determining the chemical composition of an ore is one of the means of ascertaining its provenance. Laser-induced breakdown spectroscopy (LIBS) offers a means of rapidly distinguishing different geographic sources for a mineral because the LIBS plasma emission spectrum provides the complete chemical composition (i.e., "chemical fingerprint") of any material in real time. To test this idea for columbite-tantalite, three sample sets were analyzed. Partial least squares discriminant analysis (PLSDA) allows correct sample-level geographic discrimination at a success rate exceeding 90%.

  16. Laser-induced breakdown spectroscopy used to detect endophyte-mediated accumulation of metals by tall fescue

    Energy Technology Data Exchange (ETDEWEB)

    Martin, Madhavi Z.; Stewart, Arthur J.; Gwinn, Kimberley D.; Waller, John C.

    2010-05-01

    Laser-induced breakdown spectroscopy (LIBS) was used to determine the impact of endophyte (Neotyphodium sp.) infection on elemental composition of tall fescue (Festuca arundinacea). Leaf material from endophyte-infected (E+) and endophyte-free (E-) tall fescue populations in established plots was examined. Leaf-tissue digestates were also tested for metals, by inductively coupled plasma (ICP) mass spectrometry (MS). Seven of eleven metals (Ca, Mg, Fe, Mn, Cu, Ni, and Zn) were measured by both techniques at concentrations great enough for a reliable comparison. Mg, Zn, and Cd, a toxic metal that can be present in forage, were readily detected by LIBS, even though Cd concentrations in the plants were below levels typically achieved using ICP MS detection. Implications of these results for research on forage analysis and phytoremediation are discussed.

  17. Laser-induced Breakdown Spectroscopy used to Detect Endophyte-mediated Accumulation of Metals by Tall Fescue

    Energy Technology Data Exchange (ETDEWEB)

    Martin, Madhavi Z [ORNL; Stewart, Arthur J [ORNL; Gwinn, Dr. Kimberley [University of Tennessee, Knoxville (UTK); Waller, John C [ORNL

    2010-01-01

    Laser-induced breakdown spectroscopy was used to determine the impact of endophyte (Neotyphodium sp.) infection on elemental composition of tall fescue (Festuca arundinacea). Leaf material from endophyte-infected (E+) and endophyte-free (E-) tall fescue populations in established plots was examined. Leaf-tissue digestates were also tested for metals, by ICP-MS. Seven of eleven metals (Ca, Mg, Fe, Mn, Cu, Ni and Zn) were measured by both techniques at concentrations great enough to reliably compare. Mg, Zn, and Cd, a toxic metal that can be present in forage, were readily detected by LIBS, even though Cd concentrations in the plants were below levels typically achieved using ICP-MS detection. Implications of these results for research on forage analysis and phytoremediation are discussed.

  18. Use of Laser-Induced Breakdown Spectroscopy for the Detection of Glycemic Elements in Indian Medicinal Plants

    Directory of Open Access Journals (Sweden)

    Prashant Kumar Rai

    2013-01-01

    Full Text Available The demand for interdisciplinary research is increasing in the new millennium to help us understand complex problems and find solutions by integrating the knowledge from different disciplines. The present review is an excellent example of this and shows how unique combination of physics, chemistry, and biological techniques can be used for the evaluation of Indian medicinal herbs used for treating diabetes mellitus. Laser-induced breakdown spectroscopy (LIBS is a sensitive optical technique that is widely used for its simplicity and versatility. This review presents the most recent application of LIBS for detection of glycemic elements in medicinal plants. The characteristics of matrices, object analysis, use of laser system, and analytical performances with respect to Indian herbs are discussed.

  19. Eye-safe infrared laser-induced breakdown spectroscopy (LIBS) emissions from energetic materials

    Science.gov (United States)

    Brown, Ei E.; Hömmerich, Uwe; Yang, Clayton C.; Jin, Feng; Trivedi, Sudhir B.; Samuels, Alan C.

    2016-05-01

    Laser-induced breakdown spectroscopy is a powerful diagnostic tool for detection of trace elements by monitoring the atomic and ionic emission from laser-induced plasmas. Besides elemental emissions from conventional UV-Vis LIBS, molecular LIBS emission signatures of the target compounds were observed in the long-wave infrared (LWIR) region in recent studies. Most current LIBS studies employ the fundamental Nd:YAG laser output at 1.064 μm, which has extremely low eye-damage threshold. In this work, comparative LWIR-LIBS emissions studies using traditional 1.064 μm pumping and eye-safe laser wavelength at 1.574 μm were performed on several energetic materials for applications in chemical, biological, and explosive (CBE) sensing. A Q-switched Nd: YAG laser operating at 1.064 μm and the 1.574 μm output of a pulsed Nd:YAG pumped Optical Parametric Oscillator were employed as the excitation sources. The investigated energetic materials were studied for the appearance of LWIR-LIBS emissions (4-12 μm) that are directly indicative of oxygenated breakdown products as well as partially dissociated and recombination molecular species. The observed molecular IR LIBS emission bands showed strong correlation with FTIR absorption spectra of the studied materials for 1.064 μm and 1.574 μm pump wavelengths.

  20. 基于支持向量机回归的水体重金属激光诱导击穿光谱定量分析研究%Quantitative Analysis of Laser-Induced Breakdown Spectroscopy of Heavy Metals in Water Based on Support-Vector-Machine Regression

    Institute of Scientific and Technical Information of China (English)

    王春龙; 刘建国; 赵南京; 马明俊; 王寅; 胡丽; 张大海; 余洋; 孟德硕

    2013-01-01

    建立了基于自适应核的激光诱导击穿光谱支持向量机回归定量分析模型.通过石墨富集、洛伦兹拟合和碳内标归一化,增强等离子体信号强度,减小环境噪声和能量抖动对水体重金属浓度测量的影响.实现了基于支持向量机回归智能算法的激光诱导击穿光谱定量分析.铅铜的平均相对标准偏差分别为6.4361%和6.9291%,最大相对标准偏差分别为9.1009%和8.9280%,平均相对误差分别为1.6765%和1.2478%,最大相对误差分别为5.5759%和4.2604%,相关系数分别为0.9979和0.9997.该研究为进一步实现水中痕量金属元素的快速定量分析提供了方法和数据参考.%The quantitative analysis model of laser-induced breakdown spectroscopy with adaptive kernel is established. Effect of ambient noise and energy jitter in measured density of heavy metals is gradually removed by Lorentz fitting and carbon normalization, and the intensity of plasmas is enhanced by graphite enrichment. Quantitative analysis of laser-induced breakdown spectroscopy based on regression intelligent algorithm of support vector machine is achieved. The average relative standard deviations of lead and copper are 6.4361 % and 6.9291 % , and the maximum standard deviations are 9.1009% and 8. 9280% . The average relative errors of lead and copper are 1.6765% and 1.2478 %, and the maximum relative errors are 5. 5759% and4.2604%. The correlation coefficients of lead and copper are 0. 9979 and 0. 9997. Methods and reference data are provided for the further study of fast measurement of trace heavy metals in water by laser-induced breakdown spectroscopy.

  1. Kinetic model of atomic and molecular emissions in laser-induced breakdown spectroscopy of organic compounds.

    Science.gov (United States)

    Ma, Qianli; Dagdigian, Paul J

    2011-07-01

    A kinetic model previously developed to predict the relative intensities of atomic emission lines in laser-induced breakdown spectroscopy has been extended to include processes related to CN and C(2) molecular emissions. Simulations with this model were performed to predict the relative excited-state populations. The results from the simulations are compared with experimentally determined excited-state populations from 1,064 nm laser irradiation of organic residues on aluminum foil. The model reasonably predicts the relative intensity of the molecular emissions. Significantly, the model reproduces the vastly different temporal profiles of the atomic and molecular emissions. The latter are found to extend to much longer times after the laser pulse, and this appears to be due to the increasing concentration of the molecules versus time. From the simulations, the important processes affecting the CN and C(2) concentrations are identified.

  2. Temperature Effect on the Optical Emission Intensity in Laser Induced Breakdown Spectroscopy of Super Alloys

    Science.gov (United States)

    Darbani, S. M. R.; Ghezelbash, M.; Majd, A. E.; Soltanolkotabi, M.; Saghafifar, H.

    2014-12-01

    In this paper, the influence of heating and cooling samples on the optical emission spectra and plasma parameters of laser-induced breakdown spectroscopy for Titanium 64, Inconel 718 super alloys, and Aluminum 6061 alloy is investigated. Samples are uniformly heated up to approximately 200°C and cooled down to -78°C by an external heater and liquid nitrogen, respectively. Variations of plasma parameters like electron temperature and electron density with sample temperature are determined by using Boltzmann plot and Stark broadening methods, respectively. Heating the samples improves LIBS signal strength and broadens the width of the spectrum. On the other hand, cooling alloys causes fluctuations in the LIBS signal and decrease it to some extent, and some of the spectral peaks diminish. In addition, our results show that electron temperature and electron density depend on the sample temperature variations.

  3. Quantitative mixture fraction measurements in combustion system via laser induced breakdown spectroscopy

    KAUST Repository

    Mansour, Mohy S.

    2015-01-01

    Laser induced breakdown spectroscopy (LIBS) technique has been applied to quantitative mixture fraction measurements in flames. The measured spectra of different mixtures of natural gas and air are used to obtain the calibration parameters for local elemental mass fraction measurements and hence calculate the mixture fraction. The results are compared with the mixture fraction calculations based on the ratios of the spectral lines of H/N elements, H/O elements and C/(N+O) and they show good agreement within the reaction zone of the flames. Some deviations are observed outside the reaction zone. The ability of LIBS technique as a tool for quantitative mixture fraction as well as elemental fraction measurements in reacting and non-reacting of turbulent flames is feasible. © 2014 Elsevier Ltd. All rights reserved.

  4. Double pulse laser-induced breakdown spectroscopy of explosives: Initial study towards improved discrimination

    Energy Technology Data Exchange (ETDEWEB)

    De Lucia, Frank C. [U.S. Army Research Laboratory, AMSRD-ARL-WM-BD, Aberdeen Proving Ground, MD, 21005-5069 (United States)], E-mail: fdelucia@arl.army.mil; Gottfried, Jennifer L.; Munson, Chase A.; Miziolek, Andrzej W. [U.S. Army Research Laboratory, AMSRD-ARL-WM-BD, Aberdeen Proving Ground, MD, 21005-5069 (United States)

    2007-12-15

    Detecting trace explosive residues at standoff distances in real-time is a difficult problem. One method ideally suited for real-time standoff detection is laser-induced breakdown spectroscopy (LIBS). However, atmospheric oxygen and nitrogen contributes to the LIBS signal from the oxygen- and nitrogen-containing explosive compounds, complicating the discrimination of explosives from other organic materials. While bathing the sample in an inert gas will remove atmospheric oxygen and nitrogen interference, it cannot practically be applied for standoff LIBS. Alternatively, we have investigated the potential of double pulse LIBS to improve the discrimination of explosives by diminishing the contribution of atmospheric oxygen and nitrogen to the LIBS signal. These initial studies compare the close-contact (< 1 m) LIBS spectra of explosives using single pulse LIBS in argon with double pulse LIBS in atmosphere. We have demonstrated improved discrimination of an explosive and an organic interferent using double pulse LIBS to reduce the air entrained in the analytical plasma.

  5. Detection of Elemental Composition of Lubricating Grease Using Laser Induced Breakdown Spectroscopy

    Directory of Open Access Journals (Sweden)

    Cherry Dhiman

    2014-12-01

    Full Text Available The elemental composition of lubricating soft grease used in rail engines are studied using laser induced breakdown spectroscopy (LIBS technique. LIBS spectra of fresh, partially used and fully used grease samples are recorded using time-gated ICCD spectrometer for verification of compositional degradation of the used grease. LIBS spectra of grease samples are analyzed by comparing with emission spectra of elements published by NIST standard database. Many spectral lines of impurity elements like Fe, Cu, Ba, Mg, Mn, Ni, S, Zn, Si, Pb, Ti, Ca and Al present in the grease in ppm or ppb level in trace level concentrations are observed in excess in the used grease mainly due to wear and tear. On the other hand in fresh grease, spectral lines of Ca, Al and Na are observed predominantly.

  6. Validation of the solidifying soil process using laser-induced breakdown spectroscopy

    Science.gov (United States)

    Lin, Zhao-Xiang; Liu, Lin-Mei; Liu, Lu-Wen

    2016-09-01

    Although an Ionic Soil Stabilizer (ISS) has been widely used in landslide control, it is desirable to effectively monitor the stabilization process. With the application of laser-induced breakdown spectroscopy (LIBS), the ion contents of K, Ca, Na, Mg, Al, and Si in the permeable fluid are detected after the solidified soil samples have been permeated. The processes of the Ca ion exchange are analyzed at pressures of 2 and 3 atm, and it was determined that the cation exchanged faster as the pressure increased. The Ca ion exchanges were monitored for different stabilizer mixtures, and it was found that a ratio of 1:200 of ISS to soil is most effective. The investigated plasticity and liquidity indexes also showed that the 1:200 ratio delivers the best performance. The research work indicates that it is possible to evaluate the engineering performances of soil solidified by ISS in real time and online by LIBS.

  7. Effect of cylindrical cavity height on laser-induced breakdown spectroscopy with spatial confinement

    Science.gov (United States)

    Junfeng, Shao; Tingfeng, Wang; Jin, Guo; Anmin, Chen; Mingxing, Jin

    2017-02-01

    In this paper, we present a study on the spatial confinement effect of laser-induced plasma with a cylindrical cavity in laser-induced breakdown spectroscopy (LIBS). The emission intensity with the spatial confinement is dependent on the height of the confinement cavity. It is found that, by selecting the appropriate height of cylindrical cavity, the signal enhancement can be significantly increased. At the cylindrical cavity (diameter = 2 mm) with a height of 6 mm, the enhancement ratio has the maximum value (approximately 8.3), and the value of the relative standard deviation (RSD) (7.6%) is at a minimum, the repeatability of LIBS signal is best. The results indicate that the height of confinement cavity is very important for LIBS technique to reduce the limit of detection and improve the precision.

  8. Preliminary evaluation of laser-induced breakdown spectroscopy for tissue classification

    Energy Technology Data Exchange (ETDEWEB)

    Yueh Fangyu [Institute for Clean Energy Technology, Mississippi State University, Starkville, MS 39759 (United States); Zheng Hongbo [Department of Applied Physics, Nanjing University of Technology, Nanjing, Jiangsu, 210009 (China); Singh, Jagdish P., E-mail: singh@icet.msstate.ed [Institute for Clean Energy Technology, Mississippi State University, Starkville, MS 39759 (United States); Burgess, Shane [College of Veterinary Medicine, Mississippi State University, Mississippi State, MS 39762 (United States)

    2009-10-15

    Laser-induced breakdown spectroscopy (LIBS) is an on-line, real-time technology that can produce immediate information about the elemental contents of tissue samples. We have previously shown that LIBS may be used to distinguish cancerous from non-cancerous tissue. In this work, we study LIBS spectra produced from chicken brain, lung, spleen, liver, kidney and skeletal muscle. Different data processing techniques were used to study if the information contained in these LIBS spectra is able to differentiate between different types of tissue samples and then identify unknown tissues. We have demonstrated a clear distinguishing between each of the known tissue types with only 21 selected analyte lines from each observed LIBS spectrum. We found that in order to produce an analytical model to work well with new sample we need to have representative training data to cover a wide range of spectral variation due to experimental or environmental changes.

  9. The Influence of Acquisition Delay for Calibration-Free Laser-Induced Breakdown Spectroscopy.

    Science.gov (United States)

    Fu, Hongbo; Dong, Fengzhong; Ni, Zhibo; Wang, Jingge

    2016-03-01

    Time-resolved spectra of neutral and ionized atomic emissions from slag sample are measured by laser-induced breakdown spectroscopy (LIBS). Various factors affecting the calibration-free CF-LIBS method are carefully analyzed, and subsequently these factors are either avoided or corrected. Plasma temperature and electron density are calculated by Saha-Boltzmann plot and Stark broadening of Ca, respectively. At the same time, self-absorption and local thermodynamic equilibrium have been carefully studied. An automatic spectral lines elimination algorithm is applied to calculate plasma temperature and element concentration. The calculated element concentrations show marked changes with acquisition time increasing. Due to the influence of continuous spectrum at early times and self-absorption at late times, the large absolute errors sum is obtained in these two periods. The smallest absolute errors sum corresponds to the gate delay time 1.5 μs < td < 2 μs for our experimental setup.

  10. Double-pulse laser ablation coupled to laser-induced breakdown spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Glaus, Reto, E-mail: reglaus@ufl.edu; Hahn, David W.

    2014-08-01

    Laser ablation coupled to laser-induced breakdown spectroscopy (LA-LIBS) is an analytical method, which minimizes sample matrix effects typically found in quantitative LIBS-based direct solid analyses. This paper reports the application of double-pulse laser ablation (DP-LA) to improve the analyte response and the achievable precisions of LA-LIBS. Two coaxial laser beams were applied at the ablation site and the analytical signals were then collected from a second free-standing LIBS plasma downstream of the ablation site. Signal improvements of up to one order of magnitude were observed compared to single-pulse LA-LIBS. The effect of the interpulse delay on the observed signal-to-noise ratios was studied and the quantification capabilities of the optimized DP-LA-LIBS setup were investigated for manganese and iron in a broad range of different alloy types. A linear response was observed for manganese across the different matrices, allowing for nonmatrix-matched calibrations. Matrix effects were observed when analyzing aluminum samples, which, however, could be compensated for by applying iron as internal standard. Size distributions of the ablated material and electron density measurements provide additional insight into the double-pulse process, with additional future work suggested. - Highlights: • Double-pulse laser ablation was coupled to laser-induced breakdown spectroscopy. • Nonmatrix-matched calibration of manganese in various alloys was performed. • Improved sensitivities and precisions compared to single-pulse LA were demonstrated. • Remaining matrix effects and internal standardization are discussed.

  11. Temperature and Electron Density Determination on Laser-Induced Breakdown Spectroscopy (LIBS) Plasmas: A Physical Chemistry Experiment

    Science.gov (United States)

    Najarian, Maya L.; Chinni, Rosemarie C.

    2013-01-01

    This laboratory is designed for physical chemistry students to gain experience using laser-induced breakdown spectroscopy (LIBS) in understanding plasma diagnostics. LIBS uses a high-powered laser that is focused on the sample causing a plasma to form. The emission of this plasma is then spectrally resolved and detected. Temperature and electron…

  12. A Simple Laser Induced Breakdown Spectroscopy (LIBS) System for Use at Multiple Levels in the Undergraduate Chemistry Curriculum

    Science.gov (United States)

    Randall, David W.; Hayes, Ryan T.; Wong, Peter A.

    2013-01-01

    A LIBS (laser induced breakdown spectroscopy) spectrometer constructed by the instructor is reported for use in undergraduate analytical chemistry experiments. The modular spectrometer described here is based on commonly available components including a commercial Nd:YAG laser and a compact UV-vis spectrometer. The modular approach provides a…

  13. Laser-induced breakdown spectroscopy for the study of the pattern of silicon deposition in leaves of saccharum species

    NARCIS (Netherlands)

    Tripathi, D.K.; Kumar, R.; Chauhan, D.K.; Rai, A.K.; Bicanic, D.D.

    2011-01-01

    The spatial distribution pattern of silicon in the leaves of three species of Saccharum has been demonstrated by means of laser induced breakdown spectroscopy (LIBS). The in-situ point detection capability of LIBS was used to determine different elements in leaf samples. The concentrations of silico

  14. Discrimination between authentic and false tax stamps from liquor bottles using laser-induced breakdown spectroscopy and chemometrics

    Energy Technology Data Exchange (ETDEWEB)

    Gonzaga, Fabiano Barbieri, E-mail: fbgonzaga@inmetro.gov.br [Chemical Metrology Division, National Institute of Metrology, Quality and Technology (INMETRO), Av. Nossa Senhora das Graças, 50, Xerém, 25250-020 Duque de Caxias, RJ (Brazil); Rocha, Werickson Fortunato de Carvalho [Chemical Metrology Division, National Institute of Metrology, Quality and Technology (INMETRO), Av. Nossa Senhora das Graças, 50, Xerém, 25250-020 Duque de Caxias, RJ (Brazil); Correa, Deleon Nascimento [Technical–Scientific Police Superintendency, Criminalistic Institute Dr. Octávio Eduardo de Brito Alvarenga—IC-SPTC-SP, 05507-060 São Paulo, SP (Brazil)

    2015-07-01

    This work describes the preliminary application of a compact and low-cost laser-induced breakdown spectroscopy (LIBS) instrument for falsification detection of tax stamps used in alcoholic beverages. The new instrument was based on a diode-pumped passively Q-switched Nd:YLF microchip laser and a mini-spectrometer containing a Czerny–Turner polichromator coupled to a non-intensified, non-gated, and non-cooled 2048 pixel linear sensor array (200 to 850 nm spectral range). Twenty-three tax stamp samples were analyzed by firing laser pulses within two different regions of each sample: a hologram and a blank paper region. For each acquired spectrum, the emitted radiation was integrated for 3000 ms under the continuous application of laser pulses at 100 Hz (integration of 300 plasmas). Principal component analysis (PCA) or hierarchical cluster analysis (HCA) of all emission spectra from the hologram or blank paper region revealed two well-defined groups of authentic and false samples. Moreover, for the hologram data, three subgroups of false samples were found. Additionally, partial least squares discriminant analysis (PLS-DA) was successfully applied for the detection of the false tax stamps using all emission spectra from hologram or blank paper region. The discrimination between the samples was mostly ascribed to different levels of calcium concentration in the samples. - Highlights: • Compact and low-cost laser-induced breakdown spectrometer • Analysis of tax stamps used in alcoholic beverages • Detection of false tax stamps using the LIBS spectra and chemometrics • Falsification detection ascribed to different levels of calcium concentration.

  15. Novel estimation of the humification degree of soil organic matter by laser-induced breakdown spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, Edilene Cristina, E-mail: edilene@iq.unesp.br [Embrapa Instrumentation, Rua XV de Novembro, 1452, CEP 13560-970 São Carlos, SP (Brazil); São Paulo State University—UNESP, Analytical Chemistry Department, P.O. Box 355, 14801-970 Rua Prof. Francisco Degni, 55, CEP 14800-900 Araraquara, SP (Brazil); Ferreira, Ednaldo José, E-mail: ednaldo.ferreira@embrapa.br [Embrapa Instrumentation, Rua XV de Novembro, 1452, CEP 13560-970 São Carlos, SP (Brazil); Villas-Boas, Paulino Ribeiro, E-mail: paulino.villas-boas@embrapa.br [Embrapa Instrumentation, Rua XV de Novembro, 1452, CEP 13560-970 São Carlos, SP (Brazil); Senesi, Giorgio Saverio, E-mail: giorgio.senesi@ba.imip.cnr.it [Institute of Inorganic Methodologies and Plasmas, CNR, Bari 70126 (Italy); Carvalho, Camila Miranda, E-mail: camilamc@gmail.com [Embrapa Instrumentation, Rua XV de Novembro, 1452, CEP 13560-970 São Carlos, SP (Brazil); Physics Institute of São Carlos, University of São Paulo, IFSC-USP, Av. Trabalhador são-carlense, 400 Pq. Arnold Schimid, 13566-590 São Carlos, SP (Brazil); Romano, Renan Arnon, E-mail: renan.romano@gmail.com [Embrapa Instrumentation, Rua XV de Novembro, 1452, CEP 13560-970 São Carlos, SP (Brazil); Physics Institute of São Carlos, University of São Paulo, IFSC-USP, Av. Trabalhador são-carlense, 400 Pq. Arnold Schimid, 13566-590 São Carlos, SP (Brazil); Martin-Neto, Ladislau, E-mail: ladislau.martin@embrapa.br [Embrapa Instrumentation, Rua XV de Novembro, 1452, CEP 13560-970 São Carlos, SP (Brazil); and others

    2014-09-01

    Soil organic matter (SOM) constitutes an important reservoir of terrestrial carbon and can be considered an alternative for atmospheric carbon storage, contributing to global warming mitigation. Soil management can favor atmospheric carbon incorporation into SOM or its release from SOM to atmosphere. Thus, the evaluation of the humification degree (HD), which is an indication of the recalcitrance of SOM, can provide an estimation of the capacity of carbon sequestration by soils under various managements. The HD of SOM can be estimated by using various analytical techniques including fluorescence spectroscopy. In the present work, the potential of laser-induced breakdown spectroscopy (LIBS) to estimate the HD of SOM was evaluated for the first time. Intensities of emission lines of Al, Mg and Ca from LIBS spectra showing correlation with fluorescence emissions determined by laser-induced fluorescence spectroscopy (LIFS) reference technique were used to obtain a multivaried calibration model based on the k-nearest neighbor (k-NN) method. The values predicted by the proposed model (A-LIBS) showed strong correlation with LIFS results with a Pearson's coefficient of 0.87. The HD of SOM obtained after normalizing A-LIBS by total carbon in the sample showed a strong correlation to that determined by LIFS (0.94), thus suggesting the great potential of LIBS for this novel application. - Highlights: • Humification degree of soil organic matter (HD) • Importance of soil organic matter HD in keeping carbon in soil • Laser induced fluorescence spectroscopy (LIFS) for HD estimation (reference method) • New LIBS application to predict HD.

  16. Real-time specific surface area measurements via laser-induced breakdown spectroscopy

    Science.gov (United States)

    Washburn, Kathryn E.; Birdwell, Justin E.; Howard, James E.

    2017-01-01

    From healthcare to cosmetics to environmental science, the specific surface area (SSA) of micro- and mesoporous materials or products can greatly affect their chemical and physical properties. SSA results are also widely used to examine source rocks in conventional and unconventional petroleum resource plays. Despite its importance, current methods to measure SSA are often cumbersome, time-consuming, or require cryogenic consumables (e.g., liquid nitrogen). These methods are not amenable to high-throughput environments, have stringent sample preparation requirements, and are not practical for use in the field. We present a new application of laser-induced breakdown spectroscopy for rapid measurement of SSA. This study evaluates geological samples, specifically organic-rich oil shales, but the approach is expected to be applicable to many other types of materials. The method uses optical emission spectroscopy to examine laser-generated plasma and quantify the amount of argon adsorbed to a sample during an inert gas purge. The technique can accommodate a wide range of sample sizes and geometries and has the potential for field use. These advantages for SSA measurement combined with the simultaneous acquisition of composition information make this a promising new approach for characterizing geologic samples and other materials.

  17. Rapid Detection of Oil Pollution in Soil by Using Laser-Induced Breakdown Spectroscopy

    Science.gov (United States)

    Ali, Khumaeni; Wahyu Setia, Budi; Asep Yoyo, Wardaya; Rinda, Hedwig; Koo Hendrik, Kurniawan

    2016-12-01

    Detection of oil pollution in soil has been carried out using laser-induced breakdown spectroscopy (LIBS). A pulsed neodymium-doped yttrium aluminum garnet (Nd:YAG) laser (1,064 nm, 8 ns, 200 mJ) was focused onto pelletized soil samples. Emission spectra were obtained from oil-contaminated soil and clean soil. The contaminated soil had almost the same spectrum profile as the clean soil and contained the same major and minor elements. However, a C-H molecular band was clearly detected in the oil-contaminated soil, while no C-H band was detected in the clean soil. Linear calibration curve of the C-H molecular band was successfully made by using a soil sample containing various concentrations of oil. The limit of detection of the C-H band in the soil sample was 0.001 mL/g. Furthermore, the emission spectrum of the contaminated soil clearly displayed titanium (Ti) lines, which were not detected in the clean soil. The existence of the C-H band and Ti lines in oil-contaminated soil can be used to clearly distinguish contaminated soil from clean soil. For comparison, the emission spectra of contaminated and clean soil were also obtained using scanning electron microscope-energy dispersive X-ray (SEM/EDX) spectroscopy, showing that the spectra obtained using LIBS are much better than using SEM/EDX, as indicated by the signal to noise ratio (S/N ratio).

  18. Emission enhancement using two orthogonal targets in double pulse laser-induced breakdown spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez-Ake, C. [Laboratorio de Fotofisica, Centro de Ciencias Aplicadas y Desarrollo Tecnologico, Universidad Nacional Autonoma de Mexico, Apartado Postal 70-186, Mexico D.F., C.P. 04510 (Mexico)], E-mail: citlali.sanchez@ccadet.unam.mx; Bolanos, Marduk [Laboratorio de Fotofisica, Centro de Ciencias Aplicadas y Desarrollo Tecnologico, Universidad Nacional Autonoma de Mexico, Apartado Postal 70-186, Mexico D.F., C.P. 04510 (Mexico); Ramirez, C.Z. [Colegio de Ciencias y Humanidades Plantel Sur, Universidad Nacional Autonoma de Mexico (Mexico)

    2009-09-15

    The enhancement of emission intensity resulting from the interaction between two laser-induced plasmas on two orthogonal targets was investigated using double pulse laser-induced breakdown spectroscopy (LIBS) at 0.7 Pa, by means of time-resolved spectroscopy and fast photography. The results showed that the interaction between both plasmas improved carbon emission intensity in comparison to a single laser-induced plasma. For all the carbon lines of interest 477.2 nm (CI), 426.7 nm (CII), and 473.4 nm (C{sub 2} Swan band head), the intensity enhancement showed a maximum at a delay between lasers in the range from 2 to 5 {mu}s; moreover it increased with the fluence of the first laser. On the other hand, in the case of C{sub 2} the intensity enhancement reached a maximum at 5 mm from the target; however it decreased with increasing fluence of the second laser. The largest intensity enhancement found was twofold for atomic species and sixfold for molecular species.

  19. Characterization of alumina-based ceramic nanocomposites by laser-induced breakdown spectroscopy

    Science.gov (United States)

    Ahmad, Kaleem; Al-Eshaikh, Mohammad A.; Kadachi, Ahmed N.

    2015-06-01

    Alumina-based hybrids containing different concentrations of carbon nanostructure and SiC nanoparticles were consolidated by the spark plasma sintering in order to obtain fully dense bulk ceramic nanocomposites. Laser-induced breakdown spectroscopy was employed to determine relationship between plasma temperature and surface hardness of the composites. The characteristic parameters of plasma generated by irradiation of laser Nd:YAG ( λ = 1064 nm) on different bulk nanocomposites were determined at different delay times and energies by assuming the LTE condition for optically thin plasma. The plasma temperatures were estimated through intensity of selected aluminum emission lines using the Boltzmann plot method. The electron density was determined using the Stark broadening of selected aluminum and silicon emission lines. The samples were mechanically characterized by the Vickers hardness test. It has been observed that the plasma temperature increases with the increase in hardness and shows a perfect linear relationship. The results suggest that calibration curve between hardness and the plasma temperature can be employed as an alternate method to estimate the hardness of nanocomposite with varying concentrations of nanostructures just by measuring the plasma temperature with better reproducibility and accuracy. Therefore, laser-induced break down spectroscopy (LIBS) offers potential applications in nuclear industry.

  20. Laser-induced breakdown spectroscopy application to control of the process of precious metal recovery and recycling

    Science.gov (United States)

    Legnaioli, S.; Lorenzetti, G.; Pardini, L.; Palleschi, V.; Pace, D. M. Diaz; Garcia, F. Anabitarte; Grassi, R.; Sorrentino, F.; Carelli, G.; Francesconi, M.; Francesconi, F.; Borgogni, R.

    2012-05-01

    In this paper, we discuss the application of laser-induced breakdown spectroscopy to precious metal alloys used for the control of the process of recovery and recycling of scraps and waste of industrial processes. In particular, the possibility to obtain sensitivity and trueness comparable to the current systems used in industrial environment in the quantitative determination of the elements of interest was explored. The present study demonstrates that laser-induced breakdown spectroscopy can be considered as a viable alternative to inductively coupled plasma optical emission spectrometry and X-ray fluorescence spectroscopy for the determination of recovered precious metals. The limits of detection obtained are of the order of 0.2 mg/g for all the elements considered. The maximum deviation with respect to the nominal concentrations is around 1 mg/g at concentrations around 20 mg/g (gold) corresponding to a relative error slightly higher than ± 5%.

  1. The use of laser-induced breakdown spectroscopy for the determination of fluorine concentration in glass ionomer cement

    Energy Technology Data Exchange (ETDEWEB)

    Kratochvíl, T., E-mail: kratochviltomm@seznam.cz [University of Pardubice, Institute of Environmental and Chemical Engineering, Studentska 573, 532 10 Pardubice (Czech Republic); Pouzar, M. [University of Pardubice, Institute of Environmental and Chemical Engineering, Studentska 573, 532 10 Pardubice (Czech Republic); Novotný, K. [Department of Chemistry, Faculty of Science, Masaryk University, Kotlářská 2, 611 37 Brno (Czech Republic); Havránek, V. [Nuclear Physics Institute of the ASCR, v.v.i., Řež, 250 68 (Czech Republic); Černohorský, T.; Zvolská, M. [University of Pardubice, Institute of Environmental and Chemical Engineering, Studentska 573, 532 10 Pardubice (Czech Republic)

    2013-10-01

    The influence of He atmosphere and gate width in laser-induced breakdown spectroscopy (LIBS) determination of fluorine concentration was investigated in detail. The measurements were realized on two double pulse LIBS devices featuring different parameters. Calibration curves, describing the relationship between the fluorine concentration and the corresponding intensity of the LIBS signal, were constructed for both LIBS devices, with and without He flow, respectively. Detection limits achieved were in the range 1.18-0.47 wt.%. The best LOD value was obtained in He atmosphere. The LIBS measurement of fluorine content is influenced by different gate widths and the atmosphere in the working chamber. The proposed method was successfully applied to the determination of fluorine concentration in glass ionomer cements. - Highlights: • The influence of atmosphere and gate width in LIBS analysis of F is investigated. • A sensitivity of LIBS measurement is affected by the atmosphere and the gate width. • A collinear arrangement is more suitable for the measurement of sample on the tape. • The LIBS analysis provides an advantage in analysis of total fluorine content. • The proposed method is useful for the quantitative LIBS analysis of F in GIC.

  2. Partial Least Squares and Neural Networks for Quantitative Calibration of Laser-induced Breakdown Spectroscopy (LIBs) of Geologic Samples

    Science.gov (United States)

    Anderson, R. B.; Morris, Richard V.; Clegg, S. M.; Humphries, S. D.; Wiens, R. C.; Bell, J. F., III; Mertzman, S. A.

    2010-01-01

    The ChemCam instrument [1] on the Mars Science Laboratory (MSL) rover will be used to obtain the chemical composition of surface targets within 7 m of the rover using Laser Induced Breakdown Spectroscopy (LIBS). ChemCam analyzes atomic emission spectra (240-800 nm) from a plasma created by a pulsed Nd:KGW 1067 nm laser. The LIBS spectra can be used in a semiquantitative way to rapidly classify targets (e.g., basalt, andesite, carbonate, sulfate, etc.) and in a quantitative way to estimate their major and minor element chemical compositions. Quantitative chemical analysis from LIBS spectra is complicated by a number of factors, including chemical matrix effects [2]. Recent work has shown promising results using multivariate techniques such as partial least squares (PLS) regression and artificial neural networks (ANN) to predict elemental abundances in samples [e.g. 2-6]. To develop, refine, and evaluate analysis schemes for LIBS spectra of geologic materials, we collected spectra of a diverse set of well-characterized natural geologic samples and are comparing the predictive abilities of PLS, cascade correlation ANN (CC-ANN) and multilayer perceptron ANN (MLP-ANN) analysis procedures.

  3. In situ Laser Induced Breakdown Spectroscopy as a tool to discriminate volcanic rocks and magmatic series, Iceland

    Energy Technology Data Exchange (ETDEWEB)

    Roux, C.P.M., E-mail: clement.roux@u-bourgogne.fr [Laboratoire interdisciplinaire Carnot de Bourgogne, UMR 6303 CNRS-Université de Bourgogne, BP 47 870, F-21078 Dijon Cedex (France); Rakovský, J.; Musset, O. [Laboratoire interdisciplinaire Carnot de Bourgogne, UMR 6303 CNRS-Université de Bourgogne, BP 47 870, F-21078 Dijon Cedex (France); Monna, F. [Laboratoire ARTéHIS, UMR 6298 CNRS-Université de Bourgogne, 6 Boulevard Gabriel, F-21000 Dijon (France); Buoncristiani, J.-F.; Pellenard, P.; Thomazo, C. [Laboratoire Biogéosciences, UMR 6282 CNRS-Université de Bourgogne, 6 Boulevard Gabriel, F-21000 Dijon (France)

    2015-01-01

    This study evaluates the potentialities of a lab-made pLIBS (portable Laser-Induced Breakdown Spectroscopy) to sort volcanic rocks belonging to various magmatic series. An in-situ chemical analysis of 19 atomic lines, including Al, Ba, Ca, Cr, Cu, Fe, Mg, Mn, Na, Si, Sr and Ti, from 21 sampled rocks was performed during a field exploration in Iceland. Iceland was chosen both for the various typologies of volcanic rocks and the rugged conditions in the field in order to test the sturdiness of the pLIPS. Elemental compositions were also measured using laboratory ICP-AES measurements on the same samples. Based on these latter results, which can be used to identify three different groups of volcanic rocks, a classification model was built in order to sort pLIBS data and to categorize unknown samples. Using a reliable statistical scheme applied to LIBS compositional data, the classification capability of the pLIBS system is clearly demonstrated (90–100% success rate). Although this prototype does not provide quantitative measurements, its use should be of particular interest for future geological field investigations. - Highlights: • Portable LIBS applied to field geology • Fast semi-quantitative geochemical analysis of volcanic rocks and magmatic series • Discriminant analysis and statistical treatments for LIBS compositional data.

  4. Dealloying evidence on corroded brass by laser-induced breakdown spectroscopy mapping and depth profiling measurements

    Science.gov (United States)

    Cerrato, R.; Casal, A.; Mateo, M. P.; Nicolas, G.

    2017-04-01

    The dealloying phenomenon, also called demetalification, is a; consequence of a corrosion problem found in binary alloys where an enrichment of one of the two main elements of the alloy is produced at the expense of the leaching of the other element. In the present work, the ability of laser induced breakdown spectroscopy (LIBS) for the detection and characterization of dealloying films formed on metal has been tested. For this purpose, specific areas of brass specimens have been subjected to a chemical attack of the surface in order to produce a selective leaching of zinc or dezincification. For the lateral and in-depth characterization of the dealloyed areas by LIBS, depth profiles, 2D and 3D maps have been generated from the treated samples and from a reference non-treated sample. The differences in the maps and depth profiles between the corroded and non-corroded regions have allowed to reveal the localization and extension of the dealloying process along the brass sample surface and to estimate the thickness of the dezincification layers, demonstrating the capability of LIBS technique for the characterization of dealloying phenomena.

  5. Development of laser induced breakdown spectroscopy for studying erosion, deposition, and fuel retention in ASDEX Upgrade

    Energy Technology Data Exchange (ETDEWEB)

    Paris, Peeter; Piip, Kaarel [Institute of Physics, University of Tartu, Tartu (Estonia); Hakola, Antti [VTT Technical Research Centre of Finland, Espoo (Finland); Laan, Matti, E-mail: matti.laan@ut.ee [Institute of Physics, University of Tartu, Tartu (Estonia); Aints, Märt [Institute of Physics, University of Tartu, Tartu (Estonia); Koivuranta, Seppo; Likonen, Jari [VTT Technical Research Centre of Finland, Espoo (Finland); Lissovski, Aleksandr [Institute of Physics, University of Tartu, Tartu (Estonia); Mayer, Matej [Max-Planck-Institut für Plasmaphysik, Garching (Germany); Neu, Rudolf [Max-Planck-Institut für Plasmaphysik, Garching (Germany); Technische Universität München, Fachgebt Plasma-Material-Wechelwirkung, Garching (Germany); Rohde, Volker; Sugiyama, Kazuyoshi [Max-Planck-Institut für Plasmaphysik, Garching (Germany)

    2015-10-15

    Highlights: • LIBS development for in situ monitoring of first walls of fusion reactors. • Testing of samples extracted from the divertor tiles of ASDEX Upgrade. • Reliable detection of deuterium depth profiles. • A method of LIBS data processing which allows to find the elemental depth profiles. • Comparison of LIBS results with those of other surface characterization methods. - Abstract: The paper deals with the development of laser induced breakdown spectroscopy (LIBS) into an in situ method for studying erosion/deposition processes at the first walls of fusion reactors. To this end, samples extracted from the divertor tiles of ASDEX Upgrade after the 2009 plasma operations were analyzed using LIBS for their composition and the results were compared with other post mortem deposition data. Quantitative depth profiles for the elemental concentrations were extracted from LIBS spectra by applying a novel data processing method. In addition, both multiline and multispot averaging procedures were applied to reduce fluctuations in the data. The LIBS concentration profiles matched qualitatively with those given by secondary ion mass spectrometry and quantitatively with the ion-beam data. The deuterium content of the samples could be reliably determined if the surface densities were >10{sup 17} at/cm{sup 2}.

  6. A review of the development of portable laser induced breakdown spectroscopy and its applications

    Energy Technology Data Exchange (ETDEWEB)

    Rakovský, J., E-mail: jozef.rakovsky@jh-inst.cas.cz [J. Heyrovský Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, Dolejškova 3, 18223 Prague 8 (Czech Republic); Čermák, P. [Department of Experimental Physics, Faculty of Mathematics, Physics and Informatics, Comenius University, Mlynská dolina F2, 842 48 Bratislava (Slovakia); Musset, O. [Laboratoire interdisciplinaire Carnot de Bourgogne, UMR CNRS 6303, Université de Bourgogne, BP 47 870, F-21078 Dijon Cedex (France); Veis, P. [Department of Experimental Physics, Faculty of Mathematics, Physics and Informatics, Comenius University, Mlynská dolina F2, 842 48 Bratislava (Slovakia)

    2014-11-01

    In this review, we present person-transportable laser induced breakdown spectroscopy (LIBS) devices that have previously been developed and reported in the literature as well as their applications. They are compared with X-ray fluorescent (XRF) devices, which represent their strongest competition. Although LIBS devices have advantages over XRF devices, such as sensitivity to the light elements, high spatial resolution and the possibility to distinguish between different layers of the sample, there are also disadvantages and both are discussed here. Furthermore, the essential portable LIBS instrumentation (laser, spectrograph and detector) is presented, and published results related to new laser sources (diode-pumped solid-state, microchip and fiber lasers) used in LIBS are overviewed. Compared to conventional compact flashlamp pumped solid-state lasers, the new laser sources provide higher repetition rates, higher efficiency (less power consumption) and higher beam quality, resulting in higher fluences, even for lower energies, and could potentially increase the figure of merit of portable LIBS instruments. Compact spectrometers used in portable LIBS devices and their parts (spectrograph, detector) are also discussed. - Highlights: • Overview of portable LIBS devices transportable by a person • Discussion and new trends about portable LIBS instrumentation: laser, spectrograph and detector • Overview of applications of DPSS, microchip and fiber lasers in LIBS.

  7. A compact field-portable double-pulse laser system to enhance laser induced breakdown spectroscopy

    Science.gov (United States)

    Li, Shuo; Liu, Lei; Yan, Aidong; Huang, Sheng; Huang, Xi; Chen, Rongzhang; Lu, Yongfeng; Chen, Kevin

    2017-02-01

    This paper reports the development of a compact double-pulse laser system to enhance laser induced breakdown spectroscopy (LIBS) for field applications. Pumped by high-power vertical-surface emitting lasers, the laser system that produces 16 ns pulse at 12 mJ/pulse with total weight less than 10 kg is developed. The inter-pulse delay can be adjusted from 0 μ s with 0.5 μ s increment. Several LIBS experiments were carried out on NIST standard aluminum alloy samples. Comparing with the single-pulse LIBS, up to 9 times enhancement in atomic emission line was achieved with continuum background emission reduced by 70%. This has led to up to 10 times improvement in the limit of detection. Signal stability was also improved by 128% indicating that a more robust and accurate LIBS measurement can be achieved using a compact double-pulse laser system. This paper presents a viable and field deployable laser tool to dramatically improve the sensitivity and applicability of LIBS for a wide array of applications.

  8. High-speed identification of polymers by laser-induced breakdown spectroscopy

    Science.gov (United States)

    Moench, Ingo; Sattmann, R.; Noll, Reinhard

    1997-09-01

    One way to reduce the increasing waste streams of used polymers is an efficient material recycling. This requires a technology for the separation of polymer mixtures into different material fractions. For this purpose the principal suitability of laser-induced breakdown spectroscopy was investigated. Plasma emission spectra of LDPE, HDPE, PP, PET, PVC, and PS were studied. Basic investigations were performed in order to assess the influence of different measurement parameters and to optimize the analytical performance. More than 140 spectra lines are identified, which can be related to C, H, O, N, C2, CN and CH from the bulk material and the atmosphere and to Al, Ca, Cu, Fe, Mg, Sn, Ti and Zn from additives of the polymer. Estimated detection limits of down to 2 ppm are achieved for metallic additives. Different artificial neural networks were tested for the evaluation of the spectra. PET and PVC can be identified unambiguously detecting the characteristic elements oxygen and chlorine. For plastics, which differ in their contents of inorganic additives, the line emission of additives can be used as `fingerprints' of the plastics. In this way identification accuracies of 87% to 100% for PE, PP, PET and PVC are achieved.

  9. Detection and classification of live and dead Escherichia coli by laser-induced breakdown spectroscopy.

    Science.gov (United States)

    Sivakumar, P; Fernández-Bravo, A; Taleh, L; Biddle, J F; Melikechi, N

    2015-02-01

    A common goal for astrobiology is to detect organic materials that may indicate the presence of life. However, organic materials alone may not be representative of currently living systems. Thus, it would be valuable to have a method with which to determine the health of living materials. Here, we present progress toward this goal by reporting on the application of laser-induced breakdown spectroscopy (LIBS) to study characteristics of live and dead cells using Escherichia coli (E. coli) strain K12 cells as a model organism since its growth and death in the laboratory are well understood. Our goal is to determine whether LIBS, in its femto- and/or nanosecond forms, could ascertain the state of a living organism. E. coli strain K12 cells were grown, collected, and exposed to one of two types of inactivation treatments: autoclaving and sonication. Cells were also kept alive as a control. We found that LIBS yields key information that allows for the discrimination of live and dead E. coli bacteria based on ionic shifts reflective of cell membrane integrity.

  10. Spectroscopic detection of health hazardous contaminants in lipstick using Laser Induced Breakdown Spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Gondal, M.A., E-mail: magondal@kfupm.edu.sa [Physics Department and Center of Excellence in Nanotechnology, King Fahd University of Petroleum and Minerals, Dhahran 31261 (Saudi Arabia); Seddigi, Z.S. [Chemistry Department, Umm Al-Qura University, Makkah (Saudi Arabia); Nasr, M.M. [Natural Science Departments, Riyadh College of Dentistry and Pharmacy, P.O. Box 321815, Riyadh 11343 (Saudi Arabia); Gondal, B. [Plastic and Reconstructive Aesthetic Surgery, Whitfield Hospital, Waterford (Ireland)

    2010-03-15

    Laser Induced Breakdown Spectroscopy (LIBS) technique was applied to determine the concentrations of different toxic elements like lead, chromium, cadmium and zinc in four different lipstick brands sold at local markets in Saudi Arabia. These samples contain toxic elements like lead, cadmium and chromium which are carcinogen dermatitis, allergic and eczematous. Their extraction from human body takes over 40 years and accumulation in the body cause problems like disruption of nervous systems and kidney damage. They could trigger to systemic lupus erythematosus (SLE). In order to test the validity of our LIBS results, standard technique like (ICP-AES) was also applied. To the best of our knowledge, this is the first study where LIBS technique was applied for the measurement of toxic substances in lipsticks. The maximum concentration detected in four lipstick brands was much higher than the permissible safe limits for human use and could lead to serious health problems. It is worth mentioning that the lipstick is not a solid rather is in fluid state which is not trivial to analyze using LIBS technique. For this purpose, special treatment of the lipstick samples was necessary to analyze with our LIBS method.

  11. Identification of quantum dots labeled metallothionein by fast scanning laser-induced breakdown spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Konecna, Marie [Central European Institute of Technology, Brno University of Technology, Technicka 3058/10, CZ-616 00 Brno (Czech Republic); Department of Chemistry and Biochemistry, Faculty of Agronomy, Mendel University in Brno, Zemedelska 1, CZ-613 00 Brno (Czech Republic); Novotny, Karel [Central European Institute of Technology, Masaryk University, Kamenice 753/5, CZ-625 00 Brno (Czech Republic); Krizkova, Sona [Central European Institute of Technology, Brno University of Technology, Technicka 3058/10, CZ-616 00 Brno (Czech Republic); Department of Chemistry and Biochemistry, Faculty of Agronomy, Mendel University in Brno, Zemedelska 1, CZ-613 00 Brno (Czech Republic); Blazkova, Iva [Department of Chemistry and Biochemistry, Faculty of Agronomy, Mendel University in Brno, Zemedelska 1, CZ-613 00 Brno (Czech Republic); Kopel, Pavel [Central European Institute of Technology, Brno University of Technology, Technicka 3058/10, CZ-616 00 Brno (Czech Republic); Department of Chemistry and Biochemistry, Faculty of Agronomy, Mendel University in Brno, Zemedelska 1, CZ-613 00 Brno (Czech Republic); Kaiser, Jozef [Central European Institute of Technology, Brno University of Technology, Technicka 3058/10, CZ-616 00 Brno (Czech Republic); Institute of Physical Engineering, Brno University of Technology, Technicka 2, CZ-616 69 Brno (Czech Republic); Hodek, Petr [Department of Biochemistry, Faculty of Science, Charles University in Prague, Hlavova 2030/8, CZ-128 00 Prague,Czech Republic (Czech Republic); Kizek, Rene [Central European Institute of Technology, Brno University of Technology, Technicka 3058/10, CZ-616 00 Brno (Czech Republic); Department of Chemistry and Biochemistry, Faculty of Agronomy, Mendel University in Brno, Zemedelska 1, CZ-613 00 Brno (Czech Republic); and others

    2014-11-01

    The technique described in this paper allows detection of quantum dots (QDs) specifically deposited on the polystyrene surface by laser-induced breakdown spectroscopy (LIBS). Using LIBS, the distribution of QDs or their conjugates with biomolecules deposited on the surface can be observed, regardless of the fact if they exhibit fluorescence or not. QDs deposited on the specific surface of polystyrene microplate in the form of spots are detected by determination of the metal included in the QDs structure. Cd-containing QDs (CdS, CdTe) stabilized with mercaptopropionic (MPA) or mercaptosuccinic (MSA) acid, respectively, alone or in the form of conjugates with metallothionein (MT) biomolecule are determined by using the 508.58 nm Cd emission line. The observed absolute detection limit for Cd in CdTe QDs conjugates with MT in one spot was 3 ng Cd. Due to the high sensitivity of this technique, the immunoanalysis in combination with LIBS was also investigated. Cd spatial distribution in sandwich immunoassay was detected. - Highlights: • We describe determination of biomolecules labeled with quantum dots by LIBS. • LIBS and immunoassay are applied for the determination of metallothionein. • Metallothionein amount detected by LIBS is 10-times lower compared to ELISA.

  12. Understanding the signature of rock coatings in laser-induced breakdown spectroscopy data

    Science.gov (United States)

    Lanza, Nina L.; Ollila, Ann M.; Cousin, Agnes; Wiens, Roger C.; Clegg, Samuel M.; Mangold, Nicolas; Bridges, Nathan; Cooper, Daniel; Schmidt, Mariek E.; Berger, Jeffrey; Arvidson, Raymond E.; Melikechi, Noureddine; Newsom, Horton E.; Tokar, Robert; Hardgrove, Craig; Mezzacappa, Alissa; Jackson, Ryan S.; Clark, Benton C.; Forni, Olivier; Maurice, Sylvestre; Nachon, Marion; Anderson, Ryan B.; Blank, Jennifer; Deans, Matthew; Delapp, Dorothea; Léveillé, Richard; McInroy, Rhonda; Martinez, Ronald; Meslin, Pierre-Yves; Pinet, Patrick

    2015-01-01

    Surface compositional features on rocks such as coatings and weathering rinds provide important information about past aqueous environments and water–rock interactions. The search for these features represents an important aspect of the Curiosity rover mission. With its unique ability to do fine-scale chemical depth profiling, the ChemCam laser-induced breakdown spectroscopy instrument (LIBS) onboard Curiosity can be used to both identify and analyze rock surface alteration features. In this study we analyze a terrestrial manganese-rich rock varnish coating on a basalt rock in the laboratory with the ChemCam engineering model to determine the LIBS signature of a natural rock coating. Results show that there is a systematic decrease in peak heights for elements such as Mn that are abundant in the coating but not the rock. There is significant spatial variation in the relative abundance of coating elements detected by LIBS depending on where on the rock surface sampled; this is due to the variability in thickness and spatial discontinuities in the coating. Similar trends have been identified in some martian rock targets in ChemCam data, suggesting that these rocks may have coatings or weathering rinds on their surfaces.

  13. Comparison of brass alloys composition by laser-induced breakdown spectroscopy and self-organizing maps

    Energy Technology Data Exchange (ETDEWEB)

    Pagnotta, Stefano; Grifoni, Emanuela; Legnaioli, Stefano [Applied and Laser Spectroscopy Laboratory, ICCOM-CNR, Research Area of Pisa, Via G. Moruzzi 1, 56124 Pisa (Italy); Lezzerini, Marco [Department of Earth Sciences, University of Pisa, Via S. Maria 53, 56126 Pisa (Italy); Lorenzetti, Giulia [Applied and Laser Spectroscopy Laboratory, ICCOM-CNR, Research Area of Pisa, Via G. Moruzzi 1, 56124 Pisa (Italy); Palleschi, Vincenzo, E-mail: vincenzo.palleschi@cnr.it [Applied and Laser Spectroscopy Laboratory, ICCOM-CNR, Research Area of Pisa, Via G. Moruzzi 1, 56124 Pisa (Italy); Department of Civilizations and Forms of Knowledge, University of Pisa, Via L. Galvani 1, 56126 Pisa (Italy)

    2015-01-01

    In this paper we face the problem of assessing similarities in the composition of different metallic alloys, using the laser-induced breakdown spectroscopy technique. The possibility of determining the degree of similarity through the use of artificial neural networks and self-organizing maps is discussed. As an example, we present a case study involving the comparison of two historical brass samples, very similar in their composition. The results of the paper can be extended to many other situations, not necessarily associated with cultural heritage and archeological studies, where objects with similar composition have to be compared. - Highlights: • A method for assessing the similarity of materials analyzed by LIBS is proposed. • Two very similar fragments of historical brass were analyzed. • Using a simple artificial neural network the composition of the two alloys was determined. • The composition of the two brass alloys was the same within the experimental error. • Using self-organizing maps, the probability of the alloys to have the same composition was assessed.

  14. Plasma diagnostics from self-absorbed doublet lines in laser-induced breakdown spectroscopy

    Science.gov (United States)

    D'Angelo, C. A.; Garcimuño, M.; Díaz Pace, D. M.; Bertuccelli, G.

    2015-10-01

    In this paper, a generalized approach is developed and applied for plasma characterization and quantitative purposes in laser-induced breakdown spectroscopy (LIBS) experiences by employing a selected pair of spectral lines belonging to the same multiplet. It is based on the comparison between experimental ratios of line parameters and the theoretical calculus obtained under the framework of a homogeneous plasma in local thermodynamic equilibrium. The applicability of the method was illustrated by using the atomic resonance transitions 279.55-280.27 nm of Mg II, which are usually detected in laser-induced plasma (LIP) during laser ablation of many kinds of targets. The laser induced plasmas were produced using a Nd:YAG laser from a pressed pellet of powdered calcium hydroxide with a concentration of 300 ppm of Mg. The experimental ratios for peak intensities, total intensities and Stark widths were obtained for different time windows and matched to the theoretical calculus. The temperature and the electron density of the plasma, as well as the Mg columnar density (the atom/ion concentration times the length of the plasma along the line-of-sight), were determined. The results were interpreted under the employed approach.

  15. Comparison of the detection characteristics of trace species using laser-induced breakdown spectroscopy and laser breakdown time-of-flight mass spectrometry.

    Science.gov (United States)

    Wang, Zhenzhen; Deguchi, Yoshihiro; Yan, Junjie; Liu, Jiping

    2015-03-11

    The rapid and precise element measurement of trace species, such as mercury, iodine, strontium, cesium, etc. is imperative for various applications, especially for industrial needs. The elements mercury and iodine were measured by two detection methods for comparison of the corresponding detection features. A laser beam was focused to induce plasma. Emission and ion signals were detected using laser-induced breakdown spectroscopy (LIBS) and laser breakdown time-of-flight mass spectrometry (LB-TOFMS). Multi-photon ionization and electron impact ionization in the plasma generation process can be controlled by the pressure and pulse width. The effect of electron impact ionization on continuum emission, coexisting molecular and atomic emissions became weakened in low pressure condition. When the pressure was less than 1 Pa, the plasma was induced by laser dissociation and multi-photon ionization in LB-TOFMS. According to the experimental results, the detection limits of mercury and iodine in N2 were 3.5 ppb and 60 ppb using low pressure LIBS. The mercury and iodine detection limits using LB-TOFMS were 1.2 ppb and 9.0 ppb, which were enhanced due to different detection features. The detection systems of LIBS and LB-TOFMS can be selected depending on the condition of each application.

  16. Comparison of the Detection Characteristics of Trace Species Using Laser-Induced Breakdown Spectroscopy and Laser Breakdown Time-of-Flight Mass Spectrometry

    Directory of Open Access Journals (Sweden)

    Zhenzhen Wang

    2015-03-01

    Full Text Available The rapid and precise element measurement of trace species, such as mercury, iodine, strontium, cesium, etc. is imperative for various applications, especially for industrial needs. The elements mercury and iodine were measured by two detection methods for comparison of the corresponding detection features. A laser beam was focused to induce plasma. Emission and ion signals were detected using laser-induced breakdown spectroscopy (LIBS and laser breakdown time-of-flight mass spectrometry (LB-TOFMS. Multi-photon ionization and electron impact ionization in the plasma generation process can be controlled by the pressure and pulse width. The effect of electron impact ionization on continuum emission, coexisting molecular and atomic emissions became weakened in low pressure condition. When the pressure was less than 1 Pa, the plasma was induced by laser dissociation and multi-photon ionization in LB-TOFMS. According to the experimental results, the detection limits of mercury and iodine in N2 were 3.5 ppb and 60 ppb using low pressure LIBS. The mercury and iodine detection limits using LB-TOFMS were 1.2 ppb and 9.0 ppb, which were enhanced due to different detection features. The detection systems of LIBS and LB-TOFMS can be selected depending on the condition of each application.

  17. Ultra-short laser pulse ablation using shear-force feedback: Femtosecond laser induced breakdown spectroscopy feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    Samek, Ota [ISAS-Institute for Analytical Sciences, Bunsen-Kirchhoff Str.11, 44139 Dortmund (Germany)]. E-mail: samek@ansci.de; Kurowski, Andre [ISAS-Institute for Analytical Sciences, Bunsen-Kirchhoff Str.11, 44139 Dortmund (Germany); Kittel, Silke [ISAS-Institute for Analytical Sciences, Bunsen-Kirchhoff Str.11, 44139 Dortmund (Germany); Kukhlevsky, Sergei [Institute of Physics, University of Pecs, Ifjusag u. 6, Pecs 7624 (Hungary); Hergenroeder, Roland [ISAS-Institute for Analytical Sciences, Bunsen-Kirchhoff Str.11, 44139 Dortmund (Germany)

    2005-08-31

    This work reports on a feasibility study of proximity ablation using femtosecond pulses. Ultra-short pulses were launched to a bare tapered optical fiber and delivered to the sample. The tip-sample distance was controlled by means of shear-force feedback. Consequently, ablation craters with submicrometer dimensions were obtained. Potential analytical applications for Laser Induced Breakdown Spectroscopy (LIBS) technique, such as e.g. inclusions in steel or bio cells, are suggested.

  18. Noise Parameter Analysis of SiGe HBTs for Different Sizes in the Breakdown Region

    Directory of Open Access Journals (Sweden)

    Chie-In Lee

    2016-01-01

    Full Text Available Noise parameters of silicon germanium (SiGe heterojunction bipolar transistors (HBTs for different sizes are investigated in the breakdown region for the first time. When the emitter length of SiGe HBTs shortens, minimum noise figure at breakdown decreases. In addition, narrower emitter width also decreases noise figure of SiGe HBTs in the avalanche region. Reduction of noise performance for smaller emitter length and width of SiGe HBTs at breakdown resulted from the lower noise spectral density resulting from the breakdown mechanism. Good agreement between experimental and simulated noise performance at breakdown is achieved for different sized SiGe HBTs. The presented analysis can benefit the RF circuits operating in the breakdown region.

  19. Monte Carlo standardless approach for laser induced breakdown spectroscopy based on massive parallel graphic processing unit computing

    Science.gov (United States)

    Demidov, A.; Eschlböck-Fuchs, S.; Kazakov, A. Ya.; Gornushkin, I. B.; Kolmhofer, P. J.; Pedarnig, J. D.; Huber, N.; Heitz, J.; Schmid, T.; Rössler, R.; Panne, U.

    2016-11-01

    The improved Monte-Carlo (MC) method for standard-less analysis in laser induced breakdown spectroscopy (LIBS) is presented. Concentrations in MC LIBS are found by fitting model-generated synthetic spectra to experimental spectra. The current version of MC LIBS is based on the graphic processing unit (GPU) computation and reduces the analysis time down to several seconds per spectrum/sample. The previous version of MC LIBS which was based on the central processing unit (CPU) computation requested unacceptably long analysis times of 10's minutes per spectrum/sample. The reduction of the computational time is achieved through the massively parallel computing on the GPU which embeds thousands of co-processors. It is shown that the number of iterations on the GPU exceeds that on the CPU by a factor > 1000 for the 5-dimentional parameter space and yet requires > 10-fold shorter computational time. The improved GPU-MC LIBS outperforms the CPU-MS LIBS in terms of accuracy, precision, and analysis time. The performance is tested on LIBS-spectra obtained from pelletized powders of metal oxides consisting of CaO, Fe2O3, MgO, and TiO2 that simulated by-products of steel industry, steel slags. It is demonstrated that GPU-based MC LIBS is capable of rapid multi-element analysis with relative error between 1 and 10's percent that is sufficient for industrial applications (e.g. steel slag analysis). The results of the improved GPU-based MC LIBS are positively compared to that of the CPU-based MC LIBS as well as to the results of the standard calibration-free (CF) LIBS based on the Boltzmann plot method.

  20. Measuring the thickness of protective coatings on historic metal objects using nanosecond and femtosecond laser induced breakdown spectroscopy depth profiling

    Science.gov (United States)

    Pouli, P.; Melessanaki, K.; Giakoumaki, A.; Argyropoulos, V.; Anglos, D.

    2005-08-01

    Depth profile analysis by means of laser induced breakdown spectroscopy (LIBS) was investigated with respect to its potential to measure the thickness of different types of thin organic films used as protective coatings on historical and archaeological metal objects. For the materials examined, acrylic varnish and microcrystalline wax, the output from a nanosecond ArF excimer laser at 193 nm was found appropriate for performing a reliable profiling of the coating films leading to accurate determination of the coating thickness on the basis of the number of laser pulses required to penetrate the coating and on the ablation etch rate of the corresponding coating material under the same irradiation conditions. Nanosecond pulses at 248 nm proved inadequate to profile the coatings because of their weak absorption at the laser wavelength. In contrast, femtosecond irradiation at 248 nm yielded well-resolved profiles as a result of efficient ablation achieved through the increased non-linear absorption induced by the high power density of the ultrashort pulses.

  1. Application of Laser Induced Breakdown Spectroscopy in Early Detection of Red Palm Weevil: (Rhynchophorus ferrugineus) Infestation in Date Palm

    Science.gov (United States)

    A. Farooq, W.; G. Rasool, K.; Walid, Tawfik; S. Aldawood, A.

    2015-11-01

    The Kingdom of Saudi Arabia is one of the leading date producing countries. Unfortunately, this important fruit crop is under great threat from the red palm weevil (RPW) (Rhynchophorus ferrugineus), which is a highly invasive pest. Several techniques, including visual inspection, acoustic sensors, sniffer dogs, and pheromone traps have been tried to detect the early stages of a RPW infestation; however, each method has suffered certain logistical and implementation issues. We have applied laser induced breakdown spectroscopy (LIBS) for the early detection of RPW infestation. Through the analysis of the observed LIBS spectra of different infested and healthy samples, we have found presence of Ca, Mg, Na, C, K elements and OH, CN molecules. The spectra also reveal that with the population growth of the pest, the intensity of Mg and Ca atomic lines in LIBS spectra increases rapidly. Similar behavior is observed in the molecular lines of LIBS spectra. The obtained results indicate that the LIBS technique can be used for the early detection of RPW infestation without damaging the date palms.

  2. Detection of zinc and lead in water using evaporative preconcentration and single-particle laser-induced breakdown spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Järvinen, Samu T., E-mail: samu.jarvinen@tut.fi; Saarela, Jaakko; Toivonen, Juha

    2013-08-01

    A novel laser-induced breakdown spectroscopy (LIBS)-based measurement method for metals in water is demonstrated. In the presented technology a small amount of sodium chloride is dissolved in the sample solution before spraying the sample into a tubular oven. After water removal monodisperse dry NaCl aerosol particles are formed where trace metals are present as additives. A single-particle LIBS analysis is then triggered with a scattering based particle detection system. Benefits are the highly increased metal concentration in the LIBS focal volume and the static NaCl-matrix which can be exploited in the signal processing procedure. Emitted light from the emerged plasma plume is collected with wide angle optics and dispersed with a grating spectrometer. In an aqueous solution, the respective limits of detection for zinc and lead were 0.3 ppm and 0.1 ppm using a relatively low 14 mJ laser pulse energy. Zn/Na peak intensity ratio calibration curve for zinc concentration was also determined and LIBS signal dependence on laser pulse energy was investigated. - Highlights: • Metals in a water sample are preconcentrated inside drying salt water droplets. • LIBS measurement from a single 5 μm dry salt particle using low laser pulse energy. • Stable sodium matrix can be utilized in the signal processing. • 0.3 ppm and 0.1 ppm detection limits in water obtained for Zn and Pb respectively.

  3. Can the provenance of the conflict minerals columbite and tantalite be ascertained by laser-induced breakdown spectroscopy?

    Energy Technology Data Exchange (ETDEWEB)

    Harmon, Russell S. [ARL Army Research Office, Environmental Sciences Division, Durham, NC (United States); Shughrue, Katrina M.; Hark, Richard R. [Juniata College, Department of Chemistry, Huntingdon, PA (United States); Remus, Jeremiah J. [Clarkson University, Department of Electrical and Computer Engineering, Potsdam, NY (United States); Wise, Michael A. [Smithsonian Institution, Department of Mineral Sciences, Washington, DC (United States); East, Lucille J. [Applied Spectra, Inc., Fremont, CA (United States)

    2011-07-15

    Conflict minerals is a term applied to ores mined in conditions of armed conflict and human rights abuse. Niobium and tantalum are two rare metals whose primary natural occurrence is in the complex oxide minerals columbite and tantalite, the ore of which is commonly referred to as coltan. The illicit export of coltan ore from the Democratic Republic of the Congo is thought to be responsible for financing the ongoing civil conflicts in this region. Determining the chemical composition of an ore is one of the means of ascertaining its provenance. Laser-induced breakdown spectroscopy (LIBS) offers a means of rapidly distinguishing different geographic sources for a mineral because the LIBS plasma emission spectrum provides the complete chemical composition (i.e., ''chemical fingerprint'') of any material in real time. To test this idea for columbite-tantalite, three sample sets were analyzed. Partial least squares discriminant analysis (PLSDA) allows correct sample-level geographic discrimination at a success rate exceeding 90%. (orig.)

  4. Detection of calculus by laser-induced breakdown spectroscopy (LIBS) using an ultra-short pulse laser system (USPL)

    Science.gov (United States)

    Schelle, F.; Brede, O.; Krueger, S.; Oehme, B.; Dehn, C.; Frentzen, M.; Braun, A.

    2011-03-01

    The aim of this study was to assess the detection of calculus by Laser Induced Breakdown Spectroscopy (LIBS). The study was performed with an Nd:YVO4 laser, emitting pulses with a duration of 8 ps at a wavelength of 1064 nm. A repetition rate of 500 kHz at an average power of 5 W was used. Employing a focusing lense, intensities of the order of 1011 W/cm2 were reached on the tooth surface. These high intensities led to the generation of a plasma. The light emitted by the plasma was collimated into a fibre and then analyzed by an echelle spectroscope in the wavelength region from 220 nm - 900 nm. A total number of 15 freshly extracted teeth was used for this study. For each tooth the spectra of calculus and cementum were assessed separately. Comprising all single measurements median values were calculated for the whole spectrum, leading to two specific spectra, one for calculus and one for cementum. For further statistical analysis 28 areas of interest were defined as wavelength regions, in which the signal strength differed regarding the material. In 7 areas the intensity of the calculus spectrum differed statistically significant from the intensity of the cementum spectrum (p minimally invasive method allowing a safe application in laser-guided dentistry.

  5. Study of adsorption Ag and Pb in liquid sample using Berea sandstone by commercial laser-induced breakdown spectroscopy (LIBS)

    Science.gov (United States)

    Suyanto, H.; Wendri, N.; Agustiningrum, U.; Manurung, M.

    2016-11-01

    Qualitative and quantitative analysis of Pb and Ag elements in liquid samples had been done by commercial laser-induced breakdown spectroscopy (LIBS) using adsorption method on a Berea Sandstone. The aim of this study is to identify the thickness of the Berea Sandstone for adsorbing Pb and Ag elements in liquid. The experiment was started with characterizing the Berea Sandstone that contains Si, Na, H, Li, K, Ca, O, N, Be, Ti, Al, Mg and Ba. Some of these elements have ability to adsorb Pb and Ag elements in the liquid. To prove this phenomenon, it is required to look for the experiment parameter optimum conditions such as laser energy, adsorption time and sample temperature. The experiment was conducted by dropping 2 ml standard liquid containing 1000 ppm of Pb and Ag to the Berea Sandstone surface. The result showed that the parameter optimum conditions for analyzing Pb and Ag elements in liquid sample with adsorption method were adsorption delay-time of 15 minutes, laser energy of 120 mJ and sample heating of 80 °C. The next experiment was focused on the number of adsorption as a function of depth. The data showed that Pb and Ag elements in liquid sample of 2 ml, 1000 ppm were fully adsorbed by the Berea Sandstone until the depth of 0.372 mm and 10.40 mm from the surface, respectively. The data also showed that the limit of detection predicted to about 22.76 ppm.

  6. Selective ablation of Copper-Indium-Diselenide solar cells monitored by laser-induced breakdown spectroscopy and classification methods

    Energy Technology Data Exchange (ETDEWEB)

    Diego-Vallejo, David [Technische Universität Berlin, Institute of Optics and Atomic Physics, Straße des 17, Juni 135, 10623 Berlin (Germany); Laser- und Medizin- Technologie Berlin GmbH (LMTB), Applied Laser Technology, Fabeckstr. 60-62, 14195 Berlin (Germany); Ashkenasi, David, E-mail: d.ashkenasi@lmtb.de [Laser- und Medizin- Technologie Berlin GmbH (LMTB), Applied Laser Technology, Fabeckstr. 60-62, 14195 Berlin (Germany); Lemke, Andreas [Laser- und Medizin- Technologie Berlin GmbH (LMTB), Applied Laser Technology, Fabeckstr. 60-62, 14195 Berlin (Germany); Eichler, Hans Joachim [Technische Universität Berlin, Institute of Optics and Atomic Physics, Straße des 17, Juni 135, 10623 Berlin (Germany); Laser- und Medizin- Technologie Berlin GmbH (LMTB), Applied Laser Technology, Fabeckstr. 60-62, 14195 Berlin (Germany)

    2013-09-01

    Laser-induced breakdown spectroscopy (LIBS) and two classification methods, i.e. linear correlation and artificial neural networks (ANN), are used to monitor P1, P2 and P3 scribing steps of Copper-Indium-Diselenide (CIS) solar cells. Narrow channels featuring complete removal of desired layers with minimum damage on the underlying film are expected to enhance efficiency of solar cells. The monitoring technique is intended to determine that enough material has been removed to reach the desired layer based on the analysis of plasma emission acquired during multiple pass laser scribing. When successful selective scribing is achieved, a high degree of similarity between test and reference spectra has to be identified by classification methods in order to stop the scribing procedure and avoid damaging the bottom layer. Performance of linear correlation and artificial neural networks is compared and evaluated for two spectral bandwidths. By using experimentally determined combinations of classifier and analyzed spectral band for each step, classification performance achieves errors of 7, 1 and 4% for steps P1, P2 and P3, respectively. The feasibility of using plasma emission for the supervision of processing steps of solar cell manufacturing is demonstrated. This method has the potential to be implemented as an online monitoring procedure assisting the production of solar cells. - Highlights: • LIBS and two classification methods were used to monitor CIS solar cells processing. • Selective ablation of thin-film solar cells was improved with inspection system. • Customized classification method and analyzed spectral band enhanced performance.

  7. Effect of liquid-sheet thickness on detection sensitivity for laser-induced breakdown spectroscopy of aqueous solution.

    Science.gov (United States)

    Ohba, Hironori; Saeki, Morihisa; Wakaida, Ikuo; Tanabe, Rie; Ito, Yoshiro

    2014-10-01

    For aqueous-solution-based elemental analysis, we used a thin liquid sheet (μm-scale thickness) in laser-induced breakdown spectroscopy with nanosecond laser pulses. Laser-induced plasma is emitted by focusing a pulsed Nd:YAG laser (1064 nm) on a 5- to 80-μm-thick liquid sheet in air. To optimize the conditions for detecting elements, we studied how the signal-to-background ratio (SBR) for Hα Balmer and Na-neutral emission lines depends on the liquid-sheet thickness. The SBR of the Hα Balmer and Na-neutral lines was maximized for a sheet thickness of ~20 μm at the laser energy of 100 mJ. The hydrodynamics of liquid flow induced by the laser pulse was analyzed by laser flash shadowgraph imaging. Time-resolved observation of the hydrodynamics and plasma emission suggests that the dependence of the SBR on the liquid-sheet thickness is correlated with the volume of flowing liquid that interacts with the laser pulses.

  8. Detection of tire tread particles using laser-induced breakdown spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Prochazka, David, E-mail: prochazka.d@fme.vutbr.cz [Brno University of Technology, Institute of Physical Engineering, Technická 2, 616 00 Brno (Czech Republic); Brno University of Technology, Central European Institute of Technology, Technická 3058/10, CZ-616 00 Brno (Czech Republic); Bilík, Martin [Brno University of Technology, Institute of Forensic Engineering, Údolní 244/53, 602 00 Brno (Czech Republic); Prochazková, Petra [Masaryk University, Faculty of Science, Department of Chemistry, Kamenice 735/5, 625 00 Brno (Czech Republic); Klus, Jakub; Pořízka, Pavel; Novotný, Jan [Brno University of Technology, Central European Institute of Technology, Technická 3058/10, CZ-616 00 Brno (Czech Republic); Novotný, Karel [Masaryk University, Faculty of Science, Department of Chemistry, Kamenice 735/5, 625 00 Brno (Czech Republic); Brno University of Technology, Central European Institute of Technology, Technická 3058/10, CZ-616 00 Brno (Czech Republic); Ticová, Barbora [Masaryk University, Faculty of Science, Department of Chemistry, Kamenice 735/5, 625 00 Brno (Czech Republic); Bradáč, Albert; Semela, Marek [Brno University of Technology, Institute of Forensic Engineering, Údolní 244/53, 602 00 Brno (Czech Republic); and others

    2015-06-01

    The objective of this paper is a study of the potential of laser induced breakdown spectroscopy (LIBS) for detection of tire tread particles. Tire tread particles may represent pollutants; simultaneously, it is potentially possible to exploit detection of tire tread particles for identification of optically imperceptible braking tracks at locations of road accidents. The paper describes the general composition of tire treads and selection of an element suitable for detection using the LIBS method. Subsequently, the applicable spectral line is selected considering interferences with lines of elements that might be present together with the detected particles, and optimization of measurement parameters such as incident laser energy, gate delay and gate width is performed. In order to eliminate the matrix effect, measurements were performed using 4 types of tires manufactured by 3 different producers. An adhesive tape was used as a sample carrier. The most suitable adhesive tape was selected from 5 commonly available tapes, on the basis of their respective LIBS spectra. Calibration standards, i.e. an adhesive tape with different area content of tire tread particles, were prepared for the selected tire. A calibration line was created on the basis of the aforementioned calibration standards. The linear section of this line was used for determination of the detection limit value applicable to the selected tire. Considering the insignificant influence of matrix of various types of tires, it is possible to make a simple recalculation of the detection limit value on the basis of zinc content in a specific tire. - Highlights: • LIBS experimental measurement parameters for tire tread particles were optimize. • Calibration curve was prepared. • Limit of detection was determined.

  9. Effect of atmosphere on collinear double-pulse laser-induced breakdown spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Andrew J. Effenberger, Jr.; Jill R. Scott

    2010-09-01

    Double pulse laser induced breakdown spectroscopy (DP-LIBS) has been shown to enhance LIBS spectra. Several researches have reported significant increases in signal-to-noise and or spectral intensity [1-4]. In addition to DP-LIBS, atmospheric conditions can also increase spectra intensity. For example, Iida [5] found that He and Ar both increase LIBS intensity compared to air at one 1 atm. It was also found that as the pressure was decreased to 100 Torr, LIBS intensity increased in Ar and air for single pulse (SP) LIBS. In this study, a collinear DP-LIBS scheme is used along with manipulation of the atmospheric conditions. The DP-LIBS scheme consists of a 355 nm ablative pulse fired into a sample contained in a vacuum chamber. A second analytical 1064 nm pulse is then fired 100 ns to 10 µs after and along the same path of the first pulse. Ar, He and air at pressures ranging from atmospheric pressure (630 Torr at elevation) to 10-5 Torr are introduced during DP-LIBS and SP-LIBS experiments. For a brass sample, a significant increase in spectral intensity of Cu and Zn lines were observed in DP-LIBS under Ar compared to DP-LIBS in air (Figure 1). It was also found that Cu and Zn lines acquired with SP-LIBS in Ar are nearly as intense as DP-LIBS in air. Signal-to-noise for lines from various samples will be reported for both DP-LIBS and SP-LIBS in Ar, He, and air at pressures ranging from 630 Torr to 10-5 Torr.

  10. [The auto-focusing remote laser-induced breakdown spectroscopy system].

    Science.gov (United States)

    Han, Zhen-yu; Pan, Cong-yuan; An, Ning; Du, Xue-wei; Yu, Yun-si; Du, Liang-liang; Wang, Sheng-bo; Wang, Qiu-ping

    2015-02-01

    The present paper presents an auto-focus laser-induced breakdown spectroscopy (LIBS) remote measuring system. This system contains a Schwarzschild telescope, which consists of a convex mirror and a concave mirror. The two spherical mirrors are coaxially placed. The convex mirror is mounted on a motorized linear translation stage. With this motorized linear translation stage, the convex mirror can move along the optical axis to change the spacing between the convex mirror and the concave mirror. Therefore the focal length can be adjusted to focus the laser on samples at different distances and collect the plasma spectra. The advantages of the telescope system include, firstly, the light path of laser focusing and spectra signal collection is the same, which make it easier for mounting and collimation; secondly, the light path of the telescope uses total reflection type, which is fit for the detection in ultra-violate region; finally, the telescope consists of only two spherical mirrors which are relatively easier to manufacture. Within the translation range of the motorized linear translation stage, the focal length of the telescope in this paper can be adjusted from 1.5 to 3.6 m. The diameter of the focusing spot varies from 0.5 to 1.0 mm. Utilizing this telescope system, LIBS experiments were conducted using copper sample. And the characteristic lines of Cu element (Cu I 223.01 nm, Cu I 224.43 nm) obtained are used for the auto focusing. By investigating the relation of the area of spectral lines covered and the spacing between the mirrors, the optimal laser focusing location was obtained. The LIBS experiment results show that the system functions well, fulfilling the demand of remote ablation of sample and LIBS spectral measuring, and the telescope is able to auto-focus the laser on samples at different position to perform remote LIBS experiment.

  11. Optimal emission enhancement in orthogonal double-pulse laser-induced breakdown spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Sanginés, R. [Centro de Ciencias Aplicadas y Desarrollo Tecnológico, Universidad Nacional Autónoma de México (CCADET-UNAM), Apartado Postal 70-186, México, DF 04510 (Mexico); Cátedra CONACyT, Centro de Nanociencias y Nanotecnología, Universidad Nacional Autónoma de México, Apartado Postal 14, Ensenada, BC 22800 (Mexico); Contreras, V. [Department of Physics, Tampere University of Technology, P.O. Box 692, FI-33101 Tampere (Finland); Sobral, H., E-mail: martin.sobral@ccadet.unam.mx [Centro de Ciencias Aplicadas y Desarrollo Tecnológico, Universidad Nacional Autónoma de México (CCADET-UNAM), Apartado Postal 70-186, México, DF 04510 (Mexico); Robledo-Martinez, A. [Universidad Autónoma Metropolitana-Unidad Azcapotzalco, Av. San Pablo 180, Azcapotzalco, México, DF 02200 (Mexico)

    2015-08-01

    Orthogonal double-pulse (DP) laser-induced breakdown spectroscopy (LIBS) was performed using reheating and pre-ablative configurations. The ablation pulse power density was varied by two orders of magnitude and the DP experiments were carried out for a wide range of interpulse delays. For both DP-LIBS schemes, the signal enhancement was evaluated with respect to the corresponding single-pulse (SP) LIBS as a function of the interpulse delay. The reheating scheme shows a sharp maximum signal enhancement of up to 200-fold for low ablative power densities (0.4 GW cm{sup −2}); however, for power densities larger than 10 GW cm{sup −2} this configuration did not improve the SP outcome. On the other hand, a more uniform signal enhancement of about 4–6 was obtained for the pre-ablative scheme nearly independently of the used ablative power density. In terms of the signal-to-noise ratio (SNR) the pre-ablative scheme shows a monotonic increment with the ablative power density. Whereas the reheating configuration reaches a maximum at 2.2 GW cm{sup −2}, its enhancement effect collapses markedly for fluencies above 10 GW cm{sup −2}. - Highlights: • Comparison of reheating and pre-ablative double-pulse LIBS was done using a wide range of ablation power densities. • Experimental parameters that could achieve optimal signal-to-noise ratio were investigated. • A reheating scheme is better for low-ablation power densities. • A pre-ablative configuration is better for high-ablation power densities.

  12. Laser-induced breakdown spectroscopy for the remote detection of explosives at level of fingerprints

    Science.gov (United States)

    Almaviva, S.; Palucci, A.; Lazic, V.; Menicucci, I.; Nuvoli, M.; Pistilli, M.; De Dominicis, L.

    2016-04-01

    We report the results of the application of Laser-Induced Breakdown Spectroscopy (LIBS) for the detection of some common military explosives and theirs precursors deposited on white varnished car's external and black car's internal or external plastic. The residues were deposited by an artificial silicon finger, to simulate material manipulation by terrorists when preparing a car bomb, leaving traces of explosives on the parts of a car. LIBS spectra were acquired by using a first prototype laboratory stand-off device, developed in the framework of the EU FP7 313077 project EDEN (End-user driven DEmo for CBRNe). The system operates at working distances 8-30 m and collects the LIBS in the spectral range 240-840 nm. In this configuration, the target was moved precisely in X-Y direction to simulate the scanning system, to be implemented successively. The system is equipped with two colour cameras, one for wide scene view and another for imaging with a very high magnification, capable to discern fingerprints on a target. The spectral features of each examined substance were identified and compared to those belonging to the substrate and the surrounding air, and those belonging to possible common interferents. These spectral differences are discussed and interpreted. The obtained results show that the detection and discrimination of nitro-based compounds like RDX, PETN, ammonium nitrate (AN), and urea nitrate (UN) from organic interfering substances like diesel, greasy lubricants, greasy adhesives or oils in fingerprint concentration, at stand-off distance of some meters or tenths of meters is feasible.

  13. Optical emission enhancement in laser-induced breakdown spectroscopy using micro-torches

    Science.gov (United States)

    Liu, L.; Huang, X.; Li, S.; Lu, Yao; Chen, K.; Lu, Y. F.

    2016-03-01

    A cost effective method for optical emission enhancement in laser-induced breakdown spectroscopy (LIBS) has been proposed in this research. The pulsed Nd:YAG laser with a wavelength of 532 nm was used for sample ablation and plasma generation. A cost effective commercial butane micro-torch was put parallel to the sample surface to generate a small flame above the surface. The laser-induced plasma expanded in the flame environment. The time-resolved optical emission intensity and signal-to-noise ratio (SNR) have been observed with and without micro torch. For laser with pulse energy of 20 mJ, the relationship between optical emission intensity and delay time indicates that signal intensities have been greatly enhanced in the initial several microseconds when using micro torch. The time-resolved study of signal-to-noise ratio shows that the maximum SNR occurs at the delay time of 2 μs. The laser energy effects on the enhancements of optical emission intensity and SNR have also been analyzed, which indicates that the enhancement factors are both delay time and laser energy dependent. The maximum enhancement factors for both optical emission intensity and SNR gradually decreases with the laser energy increase. The limits of detection (LODs) for aluminum (Al) and molybdenum (Mo) in steel have been estimated, which shows that the detection sensitivity has been improved by around 4 times. The LODs of Al and Mo have been reduced from 18 to 6 ppm and from 110 to 36 ppm in LIBS, respectively. The method of LIBS by a micro torch has been demonstrated to be a cost effective method for detection sensitivity improvement, especially in the situation of low laser pulse energy.

  14. Detection of Ni, Pb and Zn in water using electrodynamic single-particle levitation and laser-induced breakdown spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Järvinen, Samu T., E-mail: samu.jarvinen@tut.fi; Saari, Sampo; Keskinen, Jorma; Toivonen, Juha

    2014-09-01

    We report the development of a unique laser-induced breakdown spectroscopy (LIBS) based method for the trace metal analysis of water. The method is further applied to the analysis of aqueous samples containing known concentrations of nickel, lead and zinc. Effects that reduce the sensitivity of the LIBS analysis of aqueous samples were avoided in the presented technology by performing the LIBS analysis from a single dried salt particle which was levitated in an electric field. The salt is added to the water sample prior to analysis. A single-droplet generator injects a droplet of the solution to the measurement chamber. The droplet is trapped using electrodynamic balance technology and metals are highly concentrated as the water from the droplet rapidly evaporates without a need for additional heating. The resultant solid 7 μm particle is levitated with a high spatial stability in the LIBS focal volume. The constant mass and position of the particle enable the high reproducibility of the LIBS signal. The limits of detection in the original solution were recorded low 60 ppb, 60 ppb, and 50 ppb for nickel, lead, and zinc, respectively using low, 14 mJ excitation pulse energy. The methodology is applicable to the online monitoring of industrial waters due to the achieved sensitivity and robust instrumentation. - Highlights: • A single droplet of the water sample is trapped electrodynamically. • Metals in the droplet are rapidly preconcentrated as the water evaporates. • LIBS measurement from a single 7 μm dry salt particle using low laser pulse energy • Repeatable LIBS signal due to constant sample position and mass • Obtained detection limits for Ni, Pb and Zn were 60 ppb, 60 ppb and 50 ppb, respectively.

  15. Development of laser-induced breakdown spectroscopy sensor to assess groundwater quality impacts resulting from geologic carbon sequestration

    Science.gov (United States)

    Carson, Cantwell G.; Goueguel, Christian; Jain, Jinesh; McIntyre, Dustin

    2015-05-01

    The injection of CO2 into deep aquifers can potentially affect the quality of groundwater supplies were leakage to occur from the injection formation or fluids. Therefore, the detection of CO2 and/or entrained contaminants that migrate into shallow groundwater aquifers is important both to assess storage permanence and to evaluate impacts on water resources. Naturally occurring elements (i.e., Li, Sr) in conjunction with isotope ratios can be used to detect such leakage. We propose the use of laser induced breakdown spectroscopy (LIBS) as an analytical technique to detect a suite of elements in water samples. LIBS has real time monitoring capabilities and can be applied for elemental and isotopic analysis of solid, liquid, and gas samples. The flexibility of probe design and use of fiber optics make it a suitable technique for real time measurements in harsh conditions and in hard to reach places. The laboratory scale experiments to measure Li, K, Ca, and Sr composition of water samples indicate that the technique produces rapid and reliable data. Since CO2 leakage from saline aquifers may accompany a brine solution, we studied the effect of sodium salts on the accuracy of LIBS analysis. This work specifically also details the fabrication and application of a miniature ruggedized remotely operated diode pumped solid state passively Q-switched laser system for use as the plasma excitation source for a real time LIBS analysis. This work also proposes the optical distribution of many laser spark sources across a wide area for widespread leak detection and basin monitoring.

  16. Comparative measurements of mineral elements in milk powders with laser-induced breakdown spectroscopy and inductively coupled plasma atomic emission spectroscopy.

    Science.gov (United States)

    Lei, W Q; El Haddad, J; Motto-Ros, V; Gilon-Delepine, N; Stankova, A; Ma, Q L; Bai, X S; Zheng, L J; Zeng, H P; Yu, J

    2011-07-01

    Mineral elements contained in commercially available milk powders, including seven infant formulae and one adult milk, were analyzed with inductively coupled plasma atomic emission spectrometry (ICP-AES) and laser-induced breakdown spectroscopy (LIBS). The purpose of this work was, through a direct comparison of the analytical results, to provide an assessment of the performance of LIBS, and especially of the procedure of calibration-free LIBS (CF-LIBS), to deal with organic compounds such as milk powders. In our experiments, the matrix effect was clearly observed affecting the analytical results each time laser ablation was employed for sampling. Such effect was in addition directly observed by determining the physical parameters of the plasmas induced on the different samples. The CF-LIBS procedure was implemented to deduce the concentrations of Mg and K with Ca as the internal reference element. Quantitative analytical results with CF-LIBS were validated with ICP-AES measurements and nominal concentrations specified for commercial milks. The obtained good results with the CF-LIBS procedure demonstrate its capacity to take into account the difference in physical parameters of the plasma in the calculation of the concentrations of mineral elements, which allows a significant reduction of the matrix effect related to laser ablation. We finally discuss the way to optimize the implementation of the CF-LIBS procedure for the analysis of mineral elements in organic materials.

  17. Determination of Aluminum in Nickel-Based Superalloys by Using Laser-Induced Breakdown Spectroscopy%Determination of Aluminum in Nickel-Based Superalloys by Using Laser-Induced Breakdown Spectroscopy

    Institute of Scientific and Technical Information of China (English)

    朱德华; 王茜; 倪晓武; 陈建平; 陆建

    2011-01-01

    Laser-induced breakdown spectroscopy (LIBS) was developed to detect aluminum in nickel-based superalloys (K417, GH4033, DZ125L, З ∏742y) using a non-intensified, non-gated, low-cost detection system. The precision of LIBS depends strongly on the experimental conditions. The calibration curves of Al(I)394.4 nm and Al(I)396.2 nm under the optimum experimental parameters are presented. Finally the limit of detection (LOD) for aluminum is calculated from the experimental data, which is in the range of 0.09% to 0.1% by weight.

  18. Quantitative estimation of carbonation and chloride penetration in reinforced concrete by laser-induced breakdown spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Eto, Shuzo, E-mail: eto@criepi.denken.or.jp [Central Research Institute of Electric Power Industry, 2-6-1 Nagasaka, Yokosuka, Kanagawa 240-0196 (Japan); Matsuo, Toyofumi; Matsumura, Takuro; Fujii, Takashi [Central Research Institute of Electric Power Industry, 2-6-1 Nagasaka, Yokosuka, Kanagawa 240-0196 (Japan); Tanaka, Masayoshi Y. [Interdisciplinary Graduate School of Engineering Sciences, Kyushu University, 2-6-1 Nagasaka, Yokosuka, Kanagawa 240-0196 (Japan)

    2014-11-01

    The penetration profile of chlorine in a reinforced concrete (RC) specimen was determined by laser-induced breakdown spectroscopy (LIBS). The concrete core was prepared from RC beams with cracking damage induced by bending load and salt water spraying. LIBS was performed using a specimen that was obtained by splitting the concrete core, and the line scan of laser pulses gave the two-dimensional emission intensity profiles of 100 × 80 mm{sup 2} within one hour. The two-dimensional profile of the emission intensity suggests that the presence of the crack had less effect on the emission intensity when the measurement interval was larger than the crack width. The chlorine emission spectrum was measured without using the buffer gas, which is usually used for chlorine measurement, by collinear double-pulse LIBS. The apparent diffusion coefficient, which is one of the most important parameters for chloride penetration in concrete, was estimated using the depth profile of chlorine emission intensity and Fick's law. The carbonation depth was estimated on the basis of the relationship between carbon and calcium emission intensities. When the carbon emission intensity was statistically higher than the calcium emission intensity at the measurement point, we determined that the point was carbonated. The estimation results were consistent with the spraying test results using phenolphthalein solution. These results suggest that the quantitative estimation by LIBS of carbonation depth and chloride penetration can be performed simultaneously. - Highlights: • We estimated the carbonation depth and the apparent diffusion coefficient of chlorine sodium in the reinforced concrete with cracking damage by LIBS. • Two-dimensional profile measurement of the emission intensity in each element was performed to visualize the chloride penetration and the carbonation in the reinforced concrete. • Apparent diffusion coefficient of chlorine and sodium can be estimated using the Fick

  19. Improved Measurement Performance of Inorganic Elements in Coal by Laser-Induced Breakdown Spectroscopy Coupled with Internal Standardization

    Science.gov (United States)

    Yao, Shunchun; Xu, Jialong; Bai, Kaijie; Lu, Jidong

    2015-11-01

    Laser-induced breakdown spectroscopy was employed to determine the inorganic elements in coal. To improve the measurement's accuracy and precision, a new internal standardization scheme, which we named changed internal standardization, was compared with the traditional internal standardization and no internal standardization for the analysis of inorganic elements. The new internal standardization scheme used the atomic line of carbon at 247.86 nm and the molecular band of CN at 388.34 nm and C2 at 516.32 nm to normalize the lines of inorganic elements that were distributed in the same spectral channel. The performance of the utilization of the new internal standardization scheme was evaluated using a set of coal samples, including twenty calibration samples and five validation samples. The results show that the coefficients of determination R2 and the slope of calibration models coupled with changed internal standardization are better than that of the calibration models coupled with fixed internal standardization and no internal standardization. Moreover, the measurement accuracy and reproducibility of changed internal standardization for the analysis of five validation samples also yielded further improvement. The results that we obtained suggest that changed internal standardization could compensate for the matrix effects, as well as the influence of the difference in the spectral response of the light collection system. supported by Open Research Fund of State Key Laboratory of Pulsed Power Laser Technology of China (No. SKL2013KF03), National Natural Science Foundation of China (Nos. 51206055, 51476061), the Fundamental Research Funds for the Central Universities of China (No. 2014ZZ0014), the New Star of Pearl River on Science and Technology of Guangzhou, China (No. 2014J2200054), the Key Laboratory of Efficient and Clean Energy Utilization of Guangdong Higher Education Institutes of China (No. KLB10004) and Guangdong Province Key Laboratory of Efficient and

  20. Development of a coal quality analyzer for application to power plants based on laser-induced breakdown spectroscopy

    Science.gov (United States)

    Zhang, Lei; Gong, Yao; Li, Yufang; Wang, Xin; Fan, Juanjuan; Dong, Lei; Ma, Weiguang; Yin, Wangbao; Jia, Suotang

    2015-11-01

    It is vitally important for a power plant to determine the coal property rapidly to optimize the combustion process. In this work, a fully software-controlled laser-induced breakdown spectroscopy (LIBS) based coal quality analyzer comprising a LIBS apparatus, a sampling equipment, and a control module, has been designed for possible application to power plants for offering rapid and precise coal quality analysis results. A closed-loop feedback pulsed laser energy stabilization technology is proposed to stabilize the Nd: YAG laser output energy to a preset interval by using the detected laser energy signal so as to enhance the measurement stability and applied in a month-long monitoring experiment. The results show that the laser energy stability has been greatly reduced from ± 5.2% to ± 1.3%. In order to indicate the complex relationship between the concentrations of the analyte of interest and the corresponding plasma spectra, the support vector regression (SVR) is employed as a non-linear regression method. It is shown that this SVR method combined with principal component analysis (PCA) enables a significant improvement in cross-validation accuracy by using the calibration set of coal samples. The root mean square error for prediction of ash content, volatile matter content, and calorific value decreases from 2.74% to 1.82%, 1.69% to 1.22%, and 1.23 MJ/kg to 0.85 MJ/kg, respectively. Meanwhile, the corresponding average relative error of the predicted samples is reduced from 8.3% to 5.48%, 5.83% to 4.42%, and 5.4% to 3.68%, respectively. The enhanced levels of accuracy obtained with the SVR combined with PCA based calibration models open up avenues for prospective prediction in coal properties.

  1. Application of laser-induced breakdown spectroscopy (LIBS) as a tool to determine the origin of 'conflict minerals'

    Science.gov (United States)

    Hark, R. R.; Harmon, R. S.; Remus, J. J.; East, L. J.; Wise, M. A.; Tansi, B. M.; Shughrue, K. M.; Dunsin, K. S.; Liu, C.

    2012-04-01

    Laser-induced breakdown spectroscopy (LIBS) offers a means of rapidly distinguishing different places of origin for a mineral because the LIBS plasma emission spectrum provides the complete chemical composition (i.e. geochemical fingerprint) of a mineral in real-time. An application of this approach with potentially significant commercial and political importance is the spectral fingerprinting of the 'conflict minerals' columbite-tantalite ("coltan"). Following a successful pilot study of three columbite-tantalite suites from the United States and Canada, a more geographically diverse set of samples from 37 locations worldwide were analyzed using a commercial laboratory LIBS system and a subset of samples also analyzed using a prototype broadband field-portable system. The spectral range from 250-490 nm was chosen for the laboratory analysis to encompass many of the intense emission lines for the major elements (Ta, Nb, Fe, Mn) and the significant trace elements (e.g., W, Ti, Zr, Sn, U, Sb, Ca, Zn, Pb, Y, Mg, and Sc) known to commonly substitute in the columbite-tantalite solid solution series crystal structure and in the columbite group minerals. The field-portable instrument offered an increased spectral range (198-1005 nm), over which all elements have spectral emission lines, and higher resolution than the laboratory instrument. In both cases, the LIBS spectra were analyzed using advanced multivariate statistical signal processing techniques. Partial Least Squares Discriminant Analysis (PLSDA) resulted in a correct place-level geographic classification at success rates between 90 and 100%. The possible role of rare-earth elements (REE's) as a factor contributing to the high levels of sample discrimination was explored. Given the fact that it can be deployed as a man-portable analytical technology, these results lend additional evidence that LIBS has the potential to be utilized in the field as a real-time tool to discriminate between columbite-tantalite ores of

  2. Relative Determination of Micronutrients of Different Species of Teff (Eragrestis Seeds of Ethiopia Origin by Calibration Free Laser Induced Breakdown Spectroscopy Techniques

    Directory of Open Access Journals (Sweden)

    M. Dilbetigle Assefa

    2013-03-01

    Full Text Available The laser-induced breakdown spectroscopy techniques has been used to analysis the multi-component of three different species of Teff seeds (Red, White and Sirgegna of Ethiopia origin using a second harmonic (532 nm of a nanosecond Q-switched Nd: YAG laser focused on the surface of the pelletized powder of Teff seeds. Based on the idea of the plasma is homogeneous. The seven essential micronutrients in three species of Teff seeds are identified carbon as a matrix element. Electron density and plasma temperature are calculated applying Saha-Boltzmann equation and Boltzmann plot method. And making use of the semi-quantitative method the three species relative concentrations of (Ca, Mg, Al, Si, Mn, Fe and K are obtained using Calibration Free Laser Induced Breakdown Spectroscopy (CF-LIBS technique. The result demonstrated that the relative concentrations of the some elements in the species are different. In Red Teff species Ca is more, but Mg is least. On the contrary Mg is high in Sirgegna and White Teff as compared to Red Teff And High content of Calcium, Magnesium and Iron micronutrients are found in the three species.

  3. Relative Determination of Micronutrients of Different Species of Teff (Eragrestis) Seeds of Ethiopia Origin by Calibration Free Laser Induced Breakdown Spectroscopy Technique

    Science.gov (United States)

    Mamo, Dilbetigle Assefa; Chaubey, Ashok K.

    2014-03-01

    The laser-induced breakdown spectroscopy technique has been used to analysis the multi-component of three different species of Teff seeds (Red, White and Sirgegna) of Ethiopia origin using a second harmonic (532 nm) of a nanosecond Q-switched Nd: YAG laser focused on the surface of the pelletized powder of Teff seed. Based on the idea of the plasma is homogeneous. The seven essential micronutrients in three species of Teff seeds are identified carbon as a matrix element. Electron density and plasma temperature are calculated applying Saha-Boltzmann equation and Boltzmann plot method. And making use of the semi-quantitative method the three species relative concentrations of (Ca, Mg, Al, Si, Mn, Fe and K) are obtained using Calibration Free Laser Induced Breakdown Spectroscopy (CF-LIBS) technique. The result demonstrated that the relative concentrations of the some elements in the species are different. In Red Teff species Ca is more, but Mg is least. On the contrary Mg is high in Sirgegna and White Teff as compared to Red Teff. And High content of Calcium, Magnesium and Iron micronutrients are found in the three species.

  4. Towards the determination of the geographical origin of yellow cake samples by laser-induced breakdown spectroscopy and chemometrics

    Energy Technology Data Exchange (ETDEWEB)

    Sirven, J.B.; Pailloux, A.; M' Baye, Y.; Coulon, N.; Alpettaz, Th.; Gosse, St. [CEA Saclay, DEN, Dept Phys Chem, 91 - Gif-sur-Yvette (France)

    2009-07-01

    Yellow cake is a commonly used name for powdered uranium concentrate, produced with the uranium ore. It is the first step in the fabrication of nuclear fuel. As it contains fissile material its circulation needs to be controlled in order to avoid proliferation. In particular there is an interest in onsite determination of the geographical origin of a sample. The yellow cake elemental composition depends on its production site and can therefore be used to identify its origin. In this work laser-induced breakdown spectroscopy (LIBS) associated with chemometrics techniques is used to discriminate yellow cake samples of different geographical origin. 11 samples, one per origin, are analyzed by a commercial equipment in laboratory experimental conditions. Spectra are then processed by multivariate techniques like Principal Components Analysis (PCA) and Soft Independent Modeling of Class Analogy (SIMCA). Successive global PCAs are first performed on the whole spectra and enable one to discriminate all samples. The method is then refined by selecting several emission lines in the spectra and by using them as input data of the chemometric treatments. With a SIMCA model applied to these data a rate of correct identification of 100% is obtained for all classes. Then to define the specifications of a future onsite LIBS system, the use of a more compact spectrometer is simulated by a numerical treatment of experimental spectra. Simultaneously the reduction of spectral data used by the model is also investigated to decrease the spectral bandwidth of the measurement. The rate of correct identification remains very high. This work shows the very good ability of SIMCA associated with LIBS to discriminate yellow cake samples with a very high rate of success, in controlled laboratory conditions. (authors)

  5. On the performance of laser-induced breakdown spectroscopy for direct determination of trace metals in lubricating oils

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Lijuan [Institut Lumière Matière, UMR5306 Université Lyon 1-CNRS, Université de Lyon, 69622 Villeurbanne Cedex (France); State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200062 (China); Cao, Fan; Xiu, Junshan; Bai, Xueshi; Motto-Ros, Vincent [Institut Lumière Matière, UMR5306 Université Lyon 1-CNRS, Université de Lyon, 69622 Villeurbanne Cedex (France); Gilon, Nicole [Institut des Sciences Analytiques, UMR5280 Université Lyon 1-CNRS, Université de Lyon, 69622 Villeurbanne Cedex (France); Zeng, Heping [State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200062 (China); Yu, Jin, E-mail: jin.yu@univ-lyon1.fr [Institut Lumière Matière, UMR5306 Université Lyon 1-CNRS, Université de Lyon, 69622 Villeurbanne Cedex (France); Key Laboratory for Laser Plasmas (Ministry of Education), Department of Physics and Astrophysics, Shanghai Jiao Tong University, Shanghai 200240 (China)

    2014-09-01

    Laser-induced breakdown spectroscopy (LIBS) provides a technique to directly determine metals in viscous liquids and especially in lubricating oils. A specific laser ablation configuration of a thin layer of oil applied on the surface of a pure aluminum target was used to evaluate the analytical figures of merit of LIBS for elemental analysis of lubricating oils. Among the analyzed oils, there were a certified 75cSt blank mineral oil, 8 virgin lubricating oils (synthetic, semi-synthetic, or mineral and of 2 different manufacturers), 5 used oils (corresponding to 5 among the 8 virgin oils), and a cooking oil. The certified blank oil and 4 virgin lubricating oils were spiked with metallo-organic standards to obtain laboratory reference samples with different oil matrix. We first established calibration curves for 3 elements, Fe, Cr, Ni, with the 5 sets of laboratory reference samples in order to evaluate the matrix effect by the comparison among the different oils. Our results show that generalized calibration curves can be built for the 3 analyzed elements by merging the measured line intensities of the 5 sets of spiked oil samples. Such merged calibration curves with good correlation of the merged data are only possible if no significant matrix effect affects the measurements of the different oils. In the second step, we spiked the remaining 4 virgin oils and the cooking oils with Fe, Cr and Ni. The accuracy and the precision of the concentration determination in these prepared oils were then evaluated using the generalized calibration curves. The concentrations of metallic elements in the 5 used lubricating oils were finally determined. - Highlights: • Direct determination of wear metals in lubricating oils using LIBS. • Generalized calibration curves for different oils. • Ablation of a thin oil layer on a pure metallic target.

  6. On the performance of laser-induced breakdown spectroscopy for direct determination of trace metals in lubricating oils

    Science.gov (United States)

    Zheng, Lijuan; Cao, Fan; Xiu, Junshan; Bai, Xueshi; Motto-Ros, Vincent; Gilon, Nicole; Zeng, Heping; Yu, Jin

    2014-09-01

    Laser-induced breakdown spectroscopy (LIBS) provides a technique to directly determine metals in viscous liquids and especially in lubricating oils. A specific laser ablation configuration of a thin layer of oil applied on the surface of a pure aluminum target was used to evaluate the analytical figures of merit of LIBS for elemental analysis of lubricating oils. Among the analyzed oils, there were a certified 75cSt blank mineral oil, 8 virgin lubricating oils (synthetic, semi-synthetic, or mineral and of 2 different manufacturers), 5 used oils (corresponding to 5 among the 8 virgin oils), and a cooking oil. The certified blank oil and 4 virgin lubricating oils were spiked with metallo-organic standards to obtain laboratory reference samples with different oil matrix. We first established calibration curves for 3 elements, Fe, Cr, Ni, with the 5 sets of laboratory reference samples in order to evaluate the matrix effect by the comparison among the different oils. Our results show that generalized calibration curves can be built for the 3 analyzed elements by merging the measured line intensities of the 5 sets of spiked oil samples. Such merged calibration curves with good correlation of the merged data are only possible if no significant matrix effect affects the measurements of the different oils. In the second step, we spiked the remaining 4 virgin oils and the cooking oils with Fe, Cr and Ni. The accuracy and the precision of the concentration determination in these prepared oils were then evaluated using the generalized calibration curves. The concentrations of metallic elements in the 5 used lubricating oils were finally determined.

  7. Sampling considerations when analyzing micrometric-sized particles in a liquid jet using laser induced breakdown spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Faye, C.B.; Amodeo, T.; Fréjafon, E. [Institut National de l' Environnement Industriel et des Risques (INERIS/DRC/CARA/NOVA), Parc Technologique Alata, BP 2, 60550 Verneuil-En-Halatte (France); Delepine-Gilon, N. [Institut des Sciences Analytiques, 5 rue de la Doua, 69100 Villeurbanne (France); Dutouquet, C., E-mail: christophe.dutouquet@ineris.fr [Institut National de l' Environnement Industriel et des Risques (INERIS/DRC/CARA/NOVA), Parc Technologique Alata, BP 2, 60550 Verneuil-En-Halatte (France)

    2014-01-01

    Pollution of water is a matter of concern all over the earth. Particles are known to play an important role in the transportation of pollutants in this medium. In addition, the emergence of new materials such as NOAA (Nano-Objects, their Aggregates and their Agglomerates) emphasizes the need to develop adapted instruments for their detection. Surveillance of pollutants in particulate form in waste waters in industries involved in nanoparticle manufacturing and processing is a telling example of possible applications of such instrumental development. The LIBS (laser-induced breakdown spectroscopy) technique coupled with the liquid jet as sampling mode for suspensions was deemed as a potential candidate for on-line and real time monitoring. With the final aim in view to obtain the best detection limits, the interaction of nanosecond laser pulses with the liquid jet was examined. The evolution of the volume sampled by laser pulses was estimated as a function of the laser energy applying conditional analysis when analyzing a suspension of micrometric-sized particles of borosilicate glass. An estimation of the sampled depth was made. Along with the estimation of the sampled volume, the evolution of the SNR (signal to noise ratio) as a function of the laser energy was investigated as well. Eventually, the laser energy and the corresponding fluence optimizing both the sampling volume and the SNR were determined. The obtained results highlight intrinsic limitations of the liquid jet sampling mode when using 532 nm nanosecond laser pulses with suspensions. - Highlights: • Micrometric-sized particles in suspensions are analyzed using LIBS and a liquid jet. • The evolution of the sampling volume is estimated as a function of laser energy. • The sampling volume happens to saturate beyond a certain laser fluence. • Its value was found much lower than the beam diameter times the jet thickness. • Particles proved not to be entirely vaporized.

  8. Determination of Cr in water solution by laser-induced breakdown spectroscopy with different univariate calibration models

    Science.gov (United States)

    Huang, Lin; Yao, Mingyin; Xu, Yuan; Liu, Muhua

    2013-04-01

    In order to prove the feasibility of laser-induced breakdown spectroscopy (LIBS) in measuring toxic metals Cr in water solution, a series of potassium bichromate standard solutions were prepared in the lab. The characteristic line intensity of Cromium (Cr) element at 357.87, 359.35, 360.53, 425.43, 427.48, and 428.97 nm was taken to build up the correlation with concentration. The indexes of relative standard deviation, intercept, slope, R 2 (coefficient of determination), and root mean square error of calibration were selected to verify the precision and accuracy of models. The comprehensive results showed that the 425.43 nm line had better superiority than other lines. And the detection limit of 6 ug/ml and repeatability of 3 % are reported. To improve the model accuracy further, the intensity ratio of single 425.43 nm line to the whole spectrum was extracted. And a linear relationship between the intensity ratio and the element Cr concentration was constructed. The results demonstrated the intensity ratio calibration had better accuracy than single line calibration, especially after smoothing. To verify the accuracy of prediction, the 100 ug/ml concentration sample was used as prediction sample. The relative error values are 13.2, 11.7, and 10.8 % for single line calibration, intensity ratio calibration with raw data, and by use of smooth processing data, respectively. The results further indicated that the intensity ratio calibration improved the accuracy of measurement than single line calibration. It is worth mentioning that the application of LIBS aiming the direct analysis of heavy metals in water is a great challenge that still needs efforts for its development and validation.

  9. Determination of the elemental composition of micrometric and submicrometric particles levitating in a low pressure Radio-Frequency plasma discharge using Laser-Induced Breakdown Spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Dutouquet, C., E-mail: Christophe.dutouquet@ineris.fr [Institut National de l' Environnement Industriel et des Risques (INERIS/DRC/CARA/NOVA), Parc Technologique Alata, BP 2, 60550 Verneuil-En-Halatte (France); Wattieaux, G. [Groupe de Recherches sur l' Énergétique des Milieux Ionisés (GREMI) UMR 6606, CNRS/Université d' Orléans, 14 rue d' Issoudun, BP 6744, 45067 Orléans Cedex 2 (France); Compagnie Industrielle des Lasers (CILAS), 8, avenue Buffon B.P. 6319 Z.I. La Source, 45063 Orleans (France); Meyer, L. [Groupe de Recherches sur l' Énergétique des Milieux Ionisés (GREMI) UMR 6606, CNRS/Université d' Orléans, 14 rue d' Issoudun, BP 6744, 45067 Orléans Cedex 2 (France); Frejafon, E. [Institut National de l' Environnement Industriel et des Risques (INERIS/DRC/CARA/NOVA), Parc Technologique Alata, BP 2, 60550 Verneuil-En-Halatte (France); Boufendi, L. [Groupe de Recherches sur l' Énergétique des Milieux Ionisés (GREMI) UMR 6606, CNRS/Université d' Orléans, 14 rue d' Issoudun, BP 6744, 45067 Orléans Cedex 2 (France)

    2013-05-01

    The LIBS (Laser-Induced Breakdown Spectroscopy) technique has shown its potential in many fields of applications including that of aerosol analysis. The latter is usually carried out on the particle flow, thereby allowing quantitative detection in various experimental conditions such as ambient air analysis or exhaust stack monitoring, to name but a few. A possible alternative method for particle analysis has been experimented combining a low pressure RF (Radio-Frequency) plasma discharge with the LIBS technique. Such approach has two peculiar features in comparison to the usual LIBS analysis. First, the particles injected in the RF plasma discharge are trapped in levitation. Second, the analysis is performed at a reduced pressure of around 1 mbar. LIBS detection at such low pressure has this peculiarity that particle vaporization is assumed to be achieved through direct laser particle interaction whereas it is caused by laser-induced plasma ignited in the gas at atmospheric pressure. The use of such particle trap could allow improving particle sampling, making organic particle analysis possible (by using an inert gas for RF plasma ignition) and even (depending on the pressure) obtaining a better signal to noise ratio. Detection of the elements of nanoparticle agglomerates made following their injection in the RF discharge has demonstrated the feasibility of such approach. Future experiments are intended to explore its potentialities when tackling issues such as process control or ambient air monitoring. - Highlights: ► Agglomerated composite nanoparticles are maintained in levitation within a trap. ► The trap consists in a low pressure Radio-Frequency (RF) plasma discharge. ► Particles are analyzed using Laser-Induced Breakdown Spectroscopy (LIBS). ► The analysis is done at RF discharge reduced pressure, namely 0.25 mbar.

  10. Fast and environmentally friendly quantitative analysis of active agents in anti-diabetic tablets by an alternative laser-induced breakdown spectroscopy (LIBS) method and comparison to a validated reversed-phase high-performance liquid chromatography (RP-HPLC) method.

    Science.gov (United States)

    Contreras, Victor Ulises; Meneses-Nava, Marco A; Ornelas-Soto, Nancy; Barbosa-García, Oracio; López-de-Alba, Pedro L; Maldonado, José L; Ramos-Ortiz, Gabriel; Acevedo-Aguilar, Francisco J; López-Martínez, Leticia

    2012-11-01

    Laser-induced breakdown spectroscopy (LIBS) is evaluated as a potential analytic technique for rapid screening and quality control of anti-diabetic tablets. This paper proposes a simple LIBS-based method for the quantitative analysis of two active pharmaceutical ingredients (APIs): metformin (Met) and glybenclamide (Gly). In order to quantify both APIs, chlorine (Cl) concentration was estimated by employing the Cl/Br optical emission ratio, where Br was introduced as internal standard. Calibration curves were prepared, achieving linearity higher than 99%. On the other hand, for comparison to the proposed method, an isocratic reversed-phase high-performance liquid chromatography (RP-HPLC) method was also developed for quantitative determination of the same analytes by ultraviolet (UV) detection. The chromatographic separation was achieved on a Phenomenex Hypersil C18, 250 mm × 4.6 mm, 5 μm column. The mobile phase was K(2)HPO(4)/H(3)PO(4)-CH(3)OH and flow rate was 1.0 mL min(-1). The method is linear over a range of 10-60 μg mL(-1) for Gly and 5-30 μg mL(-1) for Met and the correlation coefficients were ≥0.99. Recoveries were found to be in the range of 95-101%. Furthermore, four different commercial brands of each active agent were evaluated by both proposed LIBS and chromatographic methods and results were compared with each other. The comparison was satisfactorily validated by analysis of variance (ANOVA).

  11. Unreported Emission Lines of Rb, Ce, La, Sr, Y, Zr, Pb and Se Detected Using Laser-Induced Breakdown Spectroscopy

    Science.gov (United States)

    Lepore, K. H.; Mackie, J.; Dyar, M. D.; Fassett, C. I.

    2017-01-01

    Information on emission lines for major and minor elements is readily available from the National Institute of Standards and Technology (NIST) as part of the Atomic Spectra Database. However, tabulated emission lines are scarce for some minor elements and the wavelength ranges presented on the NIST database are limited to those included in existing studies. Previous work concerning minor element calibration curves measured using laser-induced break-down spectroscopy found evidence of Zn emission lines that were not documented on the NIST database. In this study, rock powders were doped with Rb, Ce, La, Sr, Y, Zr, Pb and Se in concentrations ranging from 10 percent to 10 parts per million. The difference between normalized spectra collected on samples containing 10 percent dopant and those containing only 10 parts per million were used to identify all emission lines that can be detected using LIBS (Laser-Induced Breakdown Spectroscopy) in a ChemCam-like configuration at the Mount Holyoke College LIBS facility. These emission spectra provide evidence of many previously undocumented emission lines for the elements measured here.

  12. Investigation of the differentiation of ex vivo nerve and fat tissues using laser-induced breakdown spectroscopy (LIBS): Prospects for tissue-specific laser surgery.

    Science.gov (United States)

    Mehari, Fanuel; Rohde, Maximillian; Kanawade, Rajesh; Knipfer, Christian; Adler, Werner; Klämpfl, Florian; Stelzle, Florian; Schmidt, Michael

    2016-10-01

    In the present study, the elemental compositions of fat and nerve tissue during their plasma mediated laser ablation are studied in the context of tissue differentiation for laser surgery applications by using Laser-Induced Breakdown Spectroscopy (LIBS). Tissue samples of porcine fat and nerve were prepared as ex vivo experimental objects. Plasma mediated laser ablation is performed using an Nd : YAG laser in open air and under normal stray light conditions. The performed measurements suggest that the two tissue types show a high similarity in terms of qualitative elemental composition while at the same time revealing a distinct difference in the concentration of the constituent elements. Different analysis approaches are evaluated and discussed to optimize the tissue-differentiation performance of the LIBS approach. Plasma mediated laser tissue ablation.

  13. Investigation of heavy-metal accumulation in selected plant samples using laser induced breakdown spectroscopy and laser ablation inductively coupled plasma mass spectrometry

    Science.gov (United States)

    Galiová, M.; Kaiser, J.; Novotný, K.; Novotný, J.; Vaculovič, T.; Liška, M.; Malina, R.; Stejskal, K.; Adam, V.; Kizek, R.

    2008-12-01

    Single-pulse Laser-Induced Breakdown Spectroscopy (LIBS) and Laser-Ablation Inductively Coupled Plasma Mass-Spectrometry (LA-ICP-MS) were applied for mapping the silver and copper distribution in Helianthus Annuus L. samples treated with contaminant in controlled conditions. For Ag and Cu detection the 328.07 nm Ag(I) and 324.75 nm Cu(I) lines were used, respectively. The LIBS experimental conditions (mainly the laser energy and the observation window) were optimized in order to avoid self-absorption effect in the measured spectra. In the LA-ICP-MS analysis the Ag 107 and Cu 63 isotopes were detected. The capability of these two analytical techniques for high-resolution mapping of selected trace chemical elements was demonstrated.

  14. VUV absorption spectroscopy measurements of the role of fast neutral atoms in high-power gap breakdown

    Energy Technology Data Exchange (ETDEWEB)

    FILUK,A.B.; BAILEY,JAMES E.; CUNEO,MICHAEL E.; LAKE,PATRICK WAYNE; NASH,THOMAS J.; NOACK,DONALD D.; MARON,Y.

    2000-03-20

    The maximum power achieved in a wide variety of high-power devices, including electron and ion diodes, z pinches, and microwave generators, is presently limited by anode-cathode gap breakdown. A frequently-discussed hypothesis for this effect is ionization of fast neutral atoms injected throughout the anode-cathode gap during the power pulse. The authors describe a newly-developed diagnostic tool that provides the first direct test of this hypothesis. Time-resolved vacuum-ultraviolet absorption spectroscopy is used to directly probe fast neutral atoms with 1 mm spatial resolution in the 10 mm anode-cathode gap of the SABRE 5 MV, 1 TW applied-B ion diode. Absorption spectra collected during Ar RF glow discharges and with CO{sub 2} gas fills confirm the reliability of the diagnostic technique. Throughout the 50--100 ns ion diode pulses no measurable neutral absorption is seen, setting upper limits of 0.12--1.5 x 10{sup 14} cm{sup {minus}3} for ground state fast neutral atom densities of H, C, N, O, F. The absence of molecular absorption bands also sets upper limits of 0.16--1.2 x 10{sup 15} cm{sup {minus}3} for common simple molecules. These limits are low enough to rule out ionization throughout the gap as a breakdown mechanism. This technique can now be applied to quantify the role of neutral atoms in other high-power devices.

  15. Recent developments in fast spectroscopy for plant mineral analysis

    Directory of Open Access Journals (Sweden)

    Marie evan Maarschalkerweerd

    2015-03-01

    Full Text Available Ideal fertilizer management to optimize plant productivity and quality is more relevant than ever, as global food demands increase along with the rapidly growing world population. At the same time, sub-optimal or excessive use of fertilizers leads to severe environmental damage in areas of intensive crop production. The approaches of soil and plant mineral analysis are briefly compared and discussed here, and the new techniques using fast spectroscopy that offer cheap, rapid and easy-to-use analysis of plant nutritional status are reviewed. The majority of these methods use vibrational spectroscopy, such as Visual-Near Infrared (Vis-NIR and to a lesser extent Ultraviolet (UV and Mid-Infrared (MIR spectroscopy. Advantages of and problems with application of these techniques are thoroughly discussed. Spectroscopic techniques considered having major potential for plant mineral analysis, such as chlorophyll a fluorescence, X-ray fluorescence (XRF and Laser-Induced Breakdown Spectroscopy (LIBS are also described.

  16. Approaching the ppb detection limits for copper in water using laser induced breakdown spectroscopy

    Science.gov (United States)

    Tawfik, Walid; Sawaf, Sausan

    2014-05-01

    Copper concentrations in drinking-water is very important to be monitored which can cause cancer if it exceed about 10 mg/liter. In the present work, we have developed a simple, low laser power method to improve the detection limits of laser induced plasma spectroscopy LIBS for copper in aqueous solutions with different concentrations. In this method a medium density fiberboard (MDF) wood have been used as a substrate that absorbs the liquid sample to transform laser liquid interaction to laser solid interaction. Using the fundamental wavelength of Nd:YAG laser, the constructed plasma emissions were monitored for elemental analysis. The signal-to-noise ratio SNR was optimized using low laser fluence of 32 J cm-2, and detector (CDD camera) gate delay of 0.5 μs. Both the electron temperature and density of the induced plasma were determined using Boltzmann plot and the FWHM of the Cu at 324.7 nm, respectively. The plasma temperature was found to be 1.197 eV, while the plasma density was about 1.66 x 1019 cm-3. The detection limits for Cu at 324.7 nm is found to be 131 ppb comparable to the results by others using complicated system.

  17. The use of laser-induced breakdown spectroscopy for the determination of fluorine concentration in glass ionomer cement

    Science.gov (United States)

    Kratochvíl, T.; Pouzar, M.; Novotný, K.; Havránek, V.; Černohorský, T.; Zvolská, M.

    2013-10-01

    The influence of He atmosphere and gate width in laser-induced breakdown spectroscopy (LIBS) determination of fluorine concentration was investigated in detail. The measurements were realized on two double pulse LIBS devices featuring different parameters. Calibration curves, describing the relationship between the fluorine concentration and the corresponding intensity of the LIBS signal, were constructed for both LIBS devices, with and without He flow, respectively. Detection limits achieved were in the range 1.18-0.47 wt.%. The best LOD value was obtained in He atmosphere. The LIBS measurement of fluorine content is influenced by different gate widths and the atmosphere in the working chamber. The proposed method was successfully applied to the determination of fluorine concentration in glass ionomer cements.

  18. Location and detection of explosive-contaminated human fingerprints on distant targets using standoff laser-induced breakdown spectroscopy

    Science.gov (United States)

    Lucena, P.; Gaona, I.; Moros, J.; Laserna, J. J.

    2013-07-01

    Detection of explosive-contaminated human fingerprints constitutes an analytical challenge of high significance in security issues and in forensic sciences. The use of a laser-induced breakdown spectroscopy (LIBS) sensor working at 31 m distance to the target, fitted with 2D scanning capabilities and designed for capturing spectral information from laser-induced plasmas of fingerprints is presented. Distribution chemical maps based on Na and CN emissions are used to locate and detect chloratite, DNT, TNT, RDX and PETN residues that have been deposited on the surface of aluminum and glass substrates. An effectiveness of 100% on fingerprints detection, regardless the substrate scanned, is reached. Environmental factors that affect the prevalence of the fingerprint LIBS response are discussed.

  19. Characterization of inorganic species in coal by laser-induced breakdown spectroscopy using UV and IR radiations

    Energy Technology Data Exchange (ETDEWEB)

    Mateo, M.P. [Universidad de A Coruna, Departamento de Ingenieria Industrial II, E-15403 Ferrol (A Coruna) (Spain)], E-mail: pazmateo@udc.es; Nicolas, G.; Yanez, A. [Universidad de A Coruna, Departamento de Ingenieria Industrial II, E-15403 Ferrol (A Coruna) (Spain)

    2007-12-15

    In this work, the capability of laser-induced breakdown spectroscopy for process control in a thermal power plant is presented through quantitative compositional characterization of the coal used for combustion. Laser-induced emission signal of seven samples with a range of concentrations was calibrated for quantification purposes. The eighth sample was subsequently analyzed five times as unknown in order to determine the precision and accuracy of the measurements. Two modes of operation, dynamic and static and two laser wavelengths, 1064 nm and 355 nm were employed in this study for comparison. The results revealed that UV wavelength provided better results than IR radiation in terms of accuracy for the quantification of inorganic species in coal after the comparison with conventional atomic absorption spectrometry characterization.

  20. Study on the effect of beam propagation through atmospheric turbulence on standoff nanosecond laser induced breakdown spectroscopy measurements.

    Science.gov (United States)

    Laserna, J J; Reyes, R Fernández; González, R; Tobaria, L; Lucena, P

    2009-06-08

    We report on an experimental study of the effect of atmospheric turbulence on laser induced breakdown spectroscopy (LIBS) measurements. The characteristics of the atmosphere dictate specific performance constraints to this technology. Unlike classical laboratory LIBS systems where the distance to the sample is well known and characterized, LIBS systems working at several tens of meters to the target have specific atmospheric propagation conditions that cause the quality of the LIBS signals to be affected to a significant extent. Using a new LIBS based sensor system fitted with a nanosecond laser emitting at 1064 nm, propagation effects at distances of up to 120 m were investigated. The effects observed include wander and scintillation in the outgoing laser beam and in the return atomic emission signal. Plasmas were formed on aluminium targets. Average signal levels and signal fluctuations are measured so the effect of atmospheric turbulence on LIBS measurements is quantified.

  1. Study of deuterium retention on lithiated tungsten exposed to high-flux deuterium plasma using laser-induced breakdown spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Li, Cong; Wu, Xingwei; Zhang, Chenfei [Key Laboratory of Materials Modification by Laser, Ion and Electron Beams, Chinese Ministry of Education, School of Physics and Optical Electronic Technology, Dalian University of Technology, Dalian 116024 (China); Ding, Hongbin, E-mail: hding@dlut.edu.cn [Key Laboratory of Materials Modification by Laser, Ion and Electron Beams, Chinese Ministry of Education, School of Physics and Optical Electronic Technology, Dalian University of Technology, Dalian 116024 (China); De Temmerman, G., E-mail: G.C.DeTemmerman@differ.nl [FOM Institute DIFFER, Dutch Institute for Fundamental Energy Research, Association EURATOM-FOM, Trilateral Euregio Cluster, P.O. Box 1207, 3430 BE Nieuwegein (Netherlands); Meiden, H.J. van der [FOM Institute DIFFER, Dutch Institute for Fundamental Energy Research, Association EURATOM-FOM, Trilateral Euregio Cluster, P.O. Box 1207, 3430 BE Nieuwegein (Netherlands)

    2014-10-15

    Highlights: • Deuterium retention effects on both pure tungsten and lithiated tungsten have been investigated in the linear plasma simulator Magnum-PSI by an in-situ laser-induced breakdown spectroscopy. • The lithiation can inhibit the blistering on tungsten surface. • The re-deposition of lithium results in the formation of chemical state of Li{sub 2}CO{sub 3} and tungsten oxides on a fresh surface of tungsten. - Abstract: Tungsten is under consideration for use as a plasma-facing material in the divertor region of ITER. Lithiation can significantly improve plasma performance in long-pulse tokamaks like EAST. The investigation of lithiated tungsten is important for understanding the lithium conditioning effects for EAST, where tungsten will be used as a plasma-facing material. In this paper, a few important issues of lithiated tungsten interacting with high-flux deuterium plasma have been studied, such as the effect of lithiation on deuterium retention, the profile of elemental distribution, and the chemical state of lithiated tungsten. Deuterium retention inside both pure and lithiated tungsten has been investigated for the first time in the linear plasma simulator Magnum-PSI by in-situ laser induced breakdown spectroscopy (LIBS). The results indicate that, after deuterium plasma exposure, deuterium retention could be saturated in the lithiation layer, and the lithium in the lithiated layer is chemically bound with deuterium. Moreover, the lithiation can inhibit the blistering on the tungsten surface. These results can be valuable for the application of LIBS as a diagnostic technique for plasma-facing components of tokamaks.

  2. Collinear double-pulse laser-induced breakdown spectroscopy as an in-situ diagnostic tool for wall composition in fusion devices

    Energy Technology Data Exchange (ETDEWEB)

    Hai, Ran; Liu, Ping; Wu, Ding [Key Laboratory of Materials Modification by Laser, Ion and Electron Beams, Chinese Ministry of Education, School of Physics and Optical Electronic Technology, Dalian University of Technology, Dalian 116024 (China); Ding, Hongbin, E-mail: hding@dlut.edu.cn [Key Laboratory of Materials Modification by Laser, Ion and Electron Beams, Chinese Ministry of Education, School of Physics and Optical Electronic Technology, Dalian University of Technology, Dalian 116024 (China); Wu, Jing; Luo, Guang-Nan [Institute of Plasma Physics, Chinese Academy of Sciences, PO Box 1126, Hefei 230031, Anhui (China)

    2014-10-15

    Highlights: • DP-LIBS is proposed as an in-situ diagnostic method for characterizing PFCs of EAST in vacuum. • The collinear DP-LIBS configuration overcame the sensitivity shortcomings of the conventional SP-LIBS. • Plasma emission signals are dependent on the inter-pulse delay in 3.5 × 10{sup −3} Pa. • Exposed divertor tiles were tested by DP-LIBS at low pressure and remotely. - Abstract: Our recent investigations have indicated the potential of double-pulse laser-induced breakdown spectroscopy (DP-LIBS) for analysis of the deposited impurity on divertor tiles in the experimental advanced superconducting tokamak (EAST). The collinear DP-LIBS configuration was suggested with the aim of overcoming the sensitivity shortcomings of the conventional single pulse laser-induced breakdown spectroscopy (SP-LIBS) technique in vacuum conditions. A systematic study of plasma emission signal dependence on the inter-pulse delay at 3.5 × 10{sup −3} Pa was performed, and the results were compared with the ones obtained with a single laser pulse of energy corresponding to the sum of the two pulses. For a molybdenum tile, it was found that the atomic spectral lines of Mo were enhanced by a factor of 6.5 when an inter-delay time of 1.5 μs was installed. For an exposed divertor tile, significant increases in the emission line intensities of various minor elements (such as Mo, Si, Fe, Cr, Ti, Ni and Ca) were observed in DP-LIBS, while no spectra signal was achieved in SP-LIBS. This collinear DP-LIBS technique would help us to develop a more promising system to monitor the fuel retention and impurity deposition on plasma facing components of EAST.

  3. Analysis Code for High Gradient Dielectric Insulator Surface Breakdown

    Energy Technology Data Exchange (ETDEWEB)

    Ives, Robert Lawrence [Calabazas Creek Research, Inc.; Verboncoeur, John [University of California - Berkeley; Aldan, Manuel [University of California, Berkeley

    2010-05-30

    High voltage (HV) insulators are critical components in high-energy, accelerator and pulsed power systems that drive diverse applications in the national security, nuclear weapons science, defense and industrial arenas. In these systems, the insulator may separate vacuum/non-vacuum regions or conductors with high electrical field gradients. These insulators will often fail at electric fields over an order of magnitude lower than their intrinsic dielectric strength due to flashover at the dielectric interface. Decades of studies have produced a wealth of information on fundamental processes and mechanisms important for flashover initiation, but only for relatively simple insulator configurations in controlled environments. Accelerator and pulsed power system designers are faced with applying the fundamental knowledge to complex, operational devices with escalating HV requirements. Designers are forced to rely on “best practices” and expensive prototype testing, providing boundaries for successful operation. However, the safety margin is difficult to estimate, and system design must be very conservative for situations where testing is not practicable, or replacement of failed parts is disruptive or expensive. The Phase I program demonstrated the feasibility of developing an advanced code for modeling insulator breakdown. Such a code would be of great interest for a number of applications, including high energy physics, microwave source development, fusion sciences, and other research and industrial applications using high voltage devices.

  4. Depth-resolved multilayer pigment identification in paintings: combined use of laser-induced breakdown spectroscopy (LIBS) and optical coherence tomography (OCT).

    Science.gov (United States)

    Kaszewska, Ewa A; Sylwestrzak, Marcin; Marczak, Jan; Skrzeczanowski, Wojciech; Iwanicka, Magdalena; Szmit-Naud, Elżbieta; Anglos, Demetrios; Targowski, Piotr

    2013-08-01

    A detailed feasibility study on the combined use of laser-induced breakdown spectroscopy with optical coherence tomography (LIBS/OCT), aiming at a realistic depth-resolved elemental analysis of multilayer stratigraphies in paintings, is presented. Merging a high spectral resolution LIBS system with a high spatial resolution spectral OCT instrument significantly enhances the quality and accuracy of stratigraphic analysis. First, OCT mapping is employed prior to LIBS analysis in order to assist the selection of specific areas of interest on the painting surface to be examined in detail. Then, intertwined with LIBS, the OCT instrument is used as a precise profilometer for the online determination of the depth of the ablation crater formed by individual laser pulses during LIBS depth-profile analysis. This approach is novel and enables (i) the precise in-depth scaling of elemental concentration profiles, and (ii) the recognition of layer boundaries by estimating the corresponding differences in material ablation rate. Additionally, the latter is supported, within the transparency of the object, by analysis of the OCT cross-sectional views. The potential of this method is illustrated by presenting results on the detailed analysis of the structure of an historic painting on canvas performed to aid planned restoration of the artwork.

  5. Unexpected temporal evolution of atomic spectral lines of aluminum in a laser induced breakdown spectroscopy experiment

    Energy Technology Data Exchange (ETDEWEB)

    Saad, Rawad, E-mail: rawad.saad@cea.fr [CEA, DEN, DPC, SEARS, LANIE, 91191 Gif-sur-Yvette (France); L' Hermite, Daniel, E-mail: daniel.lhermite@cea.fr [CEA, DEN, DPC, SEARS, LANIE, 91191 Gif-sur-Yvette (France); Bousquet, Bruno, E-mail: bruno.bousquet@u-bordeaux1.fr [LOMA, Université de Bordeaux, CNRS, 351 Cours de la Libération, 33405 Talence Cedex (France)

    2014-11-01

    The temporal evolution of the laser induced breakdown (LIBS) signal of a pure aluminum sample was studied under nitrogen and air atmospheres. In addition to the usual decrease of signal due to plasma cooling, unexpected temporal evolutions were observed for a spectral lines of aluminum, which revealed the existence of collisional energy transfer effects. Furthermore, molecular bands of AlN and AlO were observed in the LIBS spectra, indicating recombination of aluminum with the ambient gas. Within the experimental conditions reported in this study, both collisional energy transfer and recombination processes occurred around 1.5 μs after the laser shot. This highlights the possible influence of collisional and chemical effects inside the plasma that can play a role on LIBS signals. - Highlights: • Persistence of two Al I lines related to the 61,844 cm{sup −1} energy level only under nitrogen atmosphere. • Collisional energy transfer effect exists between aluminum and nitrogen. • Observation of molecular band of AlN (under nitrogen) and AlO (under air) after a delay time of 1.5 µs. • 20% of oxygen in air is sufficient to annihilate both the collisional energy transfer effect and the AlN molecular formation.

  6. The role of plasma shielding in collinear double-pulse femtosecond laser-induced breakdown spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Penczak, John [Department of Chemistry (m/c 111), University of Illinois at Chicago, Chicago, IL 60680-7061 (United States); Kupfer, Rotem; Bar, Ilana [Department of Physics, Ben-Gurion University of the Negev, Beer-Sheva 84105 (Israel); Gordon, Robert J. [Department of Chemistry (m/c 111), University of Illinois at Chicago, Chicago, IL 60680-7061 (United States)

    2014-07-01

    We report an experimental and theoretical study of the mechanism for the enhancement of the laser-induced breakdown signal produced by two collinear femtosecond pulses separated by a suitable delay. A bilayer sample consisting of a 500 nm thick film of Ag deposited on Al was used in the experiments, and a particle-in-cell (PIC) simulation was implemented in the theoretical part of the study. Experiments on the effect of laser polarization, performed at a 30° angle of incidence over a wide range of fluences, together with the PIC results, showed that the plasma produced by the first pulse was further excited by the second pulse. Experiments at normal incidence and a fluence of 200 J/cm{sup 2} showed that the second pulse did not penetrate the Ag layer. In addition, measurements of the effect of pulse delay on the signal supported the conclusion that double pulse enhancement is produced by plasma heating rather than by increased surface ablation. - Highlights: • We study the mechanism for collinear double-pulse enhancement of LIBS produced by a fs laser. • We use a bilayer of Ag on Al to determine which region is reached by the 2nd pulse. • Signal enhancement is produced by plasma heating rather than by increased surface ablation. • Particle-in-cell calculations show that plasma shielding plays a key role.

  7. Identification of the breakdown and analysis of transformer 22/0.4 kV

    Directory of Open Access Journals (Sweden)

    Martin Brandt

    2013-12-01

    Full Text Available The paper deals with the identification of the breakdown of the transformer withdrawn from operation because of repeated reaction of transformer protections. Successively the transformer was put of operation, removed from the distribution and put to diagnostic measurements. The analysis SFRA contributed to the interturn short circuit.

  8. STUDI PERBANDINGAN ANALISIS UNSUR PLUMBUM (PB DARI HASIL ELEKTROLISIS ANTARA METODE LASER- INDUCED BREAKDOWN SPECTROSCOPY (LIBS DENGAN METODE KONVENSIONAL

    Directory of Open Access Journals (Sweden)

    H. S. Suyanto

    2014-07-01

    Full Text Available Penelitian ini bertujuan menganalisis unsur Pb hasil proses elektrolisis dengan metode alternatif laser-induced breakdown spectroscopy (LIBS dan metode konvensional. Elektrolisis menggunakan tembaga (Cu sebagai katoda dan karbon sebagai anoda. Unsur Pb yang terdeposisi pada katoda diirradiasi laser Nd-YAG (model CFR 200, 1064nm dan emisinya (Pb I 405.7 nm ditangkap spektrometer HR 2500++ yang kemudian ditampilkan dalam intensitas fungsi panjang gelombang. Hasil penelitian menunjukkan bahwa energi laser, arus listrik dan waktu deposisi proses elektrolisis yang optimum untuk karakterisasi unsur Pb masing - masing adalah 100 mJ, 5,28 mA dan 15 menit. Aplikasi metode ini untuk analisis kuantitatif larutan Pb dengan membuat kurva kalibrasi dari kosentrasi 300 ppm sampai kosentrasi terendah yaitu 0,5 ppm, serta diperoleh deteksi limit sebesar 0,44 ppm. Sebagai perbandingan metode deteksi dengan LIBS ini telah dilakukan analisis dengan metode konvensional dengan menentukan selisih massa katoda sebelum dan sesudah elektrolisis dan diperoleh hasil yang sebanding.ABSTRACTThe aim of this research was to compare between a method of laser-induced breakdown spectroscopy (LIBS and the conventional one to analyse of Plumbum (Pb element resulted from electrolysis process. Electrolysis used copper (Cu and carbon (C as cathode and anode respectively. Plumbum element which was deposited on cathode was irradiated by Nd-YAG laser (model CFR 200, 1064nm and its emission intensity of neutral Pb I 405.7 nm in the plasma was captured by HR 2500++ spectrometer and displayed in a form of intensity as a function of wavelength. The experiment result showed that the optimum condition parameters of electrolysis: laser energy, electric current and electrolysis time duration were 100 mJ, 5.28 mA and 15 minutes respectively. An application of these conditions was done to make calibration curve of Pb element in liquid sample from 300 ppm to 0.5 ppm and resulted a limit of

  9. Pilot study of laser induced breakdown spectroscopy for tissue differentiation by monitoring the plume created during laser surgery — An approach on a feedback Laser control mechanism

    Science.gov (United States)

    Kanawade, Rajesh; Mehari, Fanuel; Knipfer, Christian; Rohde, Maximilian; Tangermann-Gerk, Katja; Schmidt, Michael; Stelzle, Florian

    2013-09-01

    This study focuses on tissue differentiation using 'Laser Induced Breakdown Spectroscopy' (LIBS) by monitoring the plasma plume created during laser surgery processes. This technique is aimed at controlling a laser surgery feedback system in real time. An Excimer laser (Ar-F 193 nm) was used for the ablation of tissue samples. Fat, muscle, nerve and skin tissue samples of bisected ex-vivo pig heads were prepared as test objects for the ablation procedure. A single fiber was used to collect emissions and deliver them to a spectrometer. The obtained LIBS spectra in the measured emissions were analyzed to determine each tissue type according to their chemical composition. The elements found in the samples and their emission spectra were in agreement with those described in literature. The collected LIBS spectra were analyzed to differentiate the tissues using statistical data analysis: Principal Component Analysis (PCA), Linear Discriminant Analysis (LDA) and Receiver Operating Characteristics (ROC). The obtained preliminary results suggest a successful differentiation of the target tissues with high sensitivity and specificity. The main goal of this study was to qualitatively identify tissue types during laser ablation, which will provide a real time feedback mechanism for clinical Laser surgery applications to significantly improve the accuracy and safety of laser surgery procedures.

  10. Detector comparison for sulfur and chlorine detection with laser induced breakdown spectroscopy in the near-infrared-region

    Science.gov (United States)

    Weritz, F.; Schaurich, D.; Wilsch, G.

    2007-12-01

    Laser-induced breakdown spectroscopy has been employed for the investigation of the sulfur and chlorine content of building materials. Both, chloride and sulfate ions are major damaging species affecting the stability and lifetime of a structure. Chlorine and sulfur are mostly detected in the VUV and the NIR. In case of building materials the main elements like calcium or iron have many strong spectral lines over the whole spectral range, so that trace elements can only be detected in spectral windows unaffected from these lines. With regard to a preferably simply, robust against dust and vibrations and portable setup only the NIR spectral features are used for civil engineering applications. Most detectors, mainly CCD cameras have rapidly decreasing quantum efficiency in the NIR. Also the quantum efficiency of the photocathode of CCD-Detectors with image intensifier is decreasing in the NIR. Different CCD-detectors were tested with respect to high quantum efficiency and high dynamic range, which is necessary for simultaneous detection of weak spectral lines from trace elements and intense spectral lines from main elements. The measurements are made on reference samples consisting of cement, hydrated cement, cement mortar and concrete with well-defined amounts of the trace elements. Experimental conditions are chosen for an optimum intensity of the trace element spectral lines. The detector systems are compared by limit of detections and the signal to noise ratio.

  11. A Comparison of Multivariate and Pre-Processing Methods for Quantitative Laser-Induced Breakdown Spectroscopy of Geologic Samples

    Science.gov (United States)

    Anderson, R. B.; Morris, R. V.; Clegg, S. M.; Bell, J. F., III; Humphries, S. D.; Wiens, R. C.

    2011-01-01

    The ChemCam instrument selected for the Curiosity rover is capable of remote laser-induced breakdown spectroscopy (LIBS).[1] We used a remote LIBS instrument similar to ChemCam to analyze 197 geologic slab samples and 32 pressed-powder geostandards. The slab samples are well-characterized and have been used to validate the calibration of previous instruments on Mars missions, including CRISM [2], OMEGA [3], the MER Pancam [4], Mini-TES [5], and Moessbauer [6] instruments and the Phoenix SSI [7]. The resulting dataset was used to compare multivariate methods for quantitative LIBS and to determine the effect of grain size on calculations. Three multivariate methods - partial least squares (PLS), multilayer perceptron artificial neural networks (MLP ANNs) and cascade correlation (CC) ANNs - were used to generate models and extract the quantitative composition of unknown samples. PLS can be used to predict one element (PLS1) or multiple elements (PLS2) at a time, as can the neural network methods. Although MLP and CC ANNs were successful in some cases, PLS generally produced the most accurate and precise results.

  12. Laser-induced breakdown spectroscopy of major and minor oxides in steel slags: Influence of detection geometry and signal normalization

    Science.gov (United States)

    Ahamer, C. M.; Eschlböck-Fuchs, S.; Kolmhofer, P. J.; Rössler, R.; Huber, N.; Pedarnig, J. D.

    2016-08-01

    Slag from secondary metallurgy in industrial steel production is analyzed by laser-induced breakdown spectroscopy (LIBS). The major oxides CaO, Al2O3, MgO, SiO2, FeO, MnO, and TiO2 are determined by calibration-free LIBS (CF-LIBS) method. For the minor oxide P2O5 calibration curves are established and the limits of detection (LOD) and the root-mean squared errors of prediction (RMSEP) are determined. The optical emission of the laser-induced plasma is measured for different detection geometries and varying sample position relative to the focal plane of the laser beam. LIBS spectra, plasma parameters, and analytical results are very similar for light collection with optical fibres close to the plasma ("direct detection") and at remote position ("collinear detection"). With collinear detection, the CF-LIBS calculated oxide concentrations are insensitive to sample position along the optical axis over wide range. The detection limits and the prediction errors of minor P2O5 depend on the major slag element used for signal normalization. With Mg and Si as internal reference elements the LOD values are 0.31 wt% and 0.07 wt%, respectively. The RMSEP values are lowest for signal normalization to Si. Calculations of the optical emission of ideal plasma support the experimental preference for Si as reference element in the phosphorous calibration.

  13. ,* Copper transport and accumulation in spruce stems (picea abies(L.) Karsten) revelaed by laser-induced breakdown spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Krajcarova, Dr. Lucie [Czech Technical University; Novotny, Dr. Karel [Mendel University of Brno; Babula, Dr. Petr [Czech Technical University; Pravaznik, Dr Ivo [Czech Technical University; Kucerova, Dr. Petra [Czech Technical University; Vojtech, Dr. Adam [Czech Technical University; Martin, Madhavi Z [ORNL; Kizek, Dr. Rene [Czech Technical University; Kaiser, Jozef [ORNL

    2013-01-01

    Laser-Induced Breakdown Spectroscopy (LIBS) in double pulse configuration (DP LIBS) was used for scanning elemental spatial distribution in annual terminal stems of spruce (Picea abies (L.) Karsten). Cross sections of stems cultivated in Cu2+ solution of different concentrations were prepared and analyzed by DP LIBS. Raster scanning with 150 m spatial resolution was set and 2D (2-dimentional) maps of Cu and Ca distribution were created on the basis of the data obtained. Stem parts originating in the vicinity of the implementation of the cross sections were mineralized and subsequently Cu and Ca contents were analyzed by inductively coupled plasma mass spectrometry (ICP-MS). The results provide quantitative information about overall concentration of the elements in places, where LIBS measurements were performed. The fluorescence pictures were created to compare LIBS distribution maps and the fluorescence intensity (or the increase in autofluorescence) was used for the comparison of ICP-MS quantitative results. Results from these three methods can be utilized for quantitative measurements of copper ions transport in different plant compartments in dependence on the concentration of cultivation medium and/or the time of cultivation.

  14. Acidity measurement of iron ore powders using laser-induced breakdown spectroscopy with partial least squares regression.

    Science.gov (United States)

    Hao, Z Q; Li, C M; Shen, M; Yang, X Y; Li, K H; Guo, L B; Li, X Y; Lu, Y F; Zeng, X Y

    2015-03-23

    Laser-induced breakdown spectroscopy (LIBS) with partial least squares regression (PLSR) has been applied to measuring the acidity of iron ore, which can be defined by the concentrations of oxides: CaO, MgO, Al₂O₃, and SiO₂. With the conventional internal standard calibration, it is difficult to establish the calibration curves of CaO, MgO, Al₂O₃, and SiO₂ in iron ore due to the serious matrix effects. PLSR is effective to address this problem due to its excellent performance in compensating the matrix effects. In this work, fifty samples were used to construct the PLSR calibration models for the above-mentioned oxides. These calibration models were validated by the 10-fold cross-validation method with the minimum root-mean-square errors (RMSE). Another ten samples were used as a test set. The acidities were calculated according to the estimated concentrations of CaO, MgO, Al₂O₃, and SiO₂ using the PLSR models. The average relative error (ARE) and RMSE of the acidity achieved 3.65% and 0.0048, respectively, for the test samples.

  15. Preliminary results of in situ laser-induced breakdown spectroscopy for the first wall diagnostics on EAST

    Science.gov (United States)

    Zhenhua, Hu; Cong, Li; Qingmei, Xiao; Ping, Liu; Fang, Ding; Hongmin, Mao; Jing, Wu; Dongye, Zhao; Hongbin, Ding; Guang-Nan, Luo; EAST Team

    2017-02-01

    Post-mortem methods cannot fulfill the requirement of monitoring the lifetime of the plasma facing components (PFC) and measuring the tritium inventory for the safety evaluation. Laser-induced breakdown spectroscopy (LIBS) is proposed as a promising method for the in situ study of fuel retention and impurity deposition in a tokamak. In this study, an in situ LIBS system was successfully established on EAST to investigate fuel retention and impurity deposition on the first wall without the need of removal tiles between plasma discharges. Spectral lines of D, H and impurities (Mo, Li, Si, … ) in laser-induced plasma were observed and identified within the wavelength range of 500-700 nm. Qualitative measurements such as thickness of the deposition layers, element depth profile and fuel retention on the wall are obtained by means of in situ LIBS. The results demonstrated the potential applications of LIBS for in situ characterization of fuel retention and co-deposition on the first wall of EAST. Supported by the National Magnetic Confinement Fusion Science Program of China (Nos. 2013GB105002, 2015GB109001, and 2013GB109005), National Natural Science Foundation of China (Nos. 11575243, 11605238, 11605023), Chinesisch-Deutsches Forschungs Project (GZ765), and Korea Research Council of Fundamental Science and Technology (KRCF) under the international collaboration & research in Asian countries (PG1314).

  16. Approach for determination of detonation performance and aluminum percentage of aluminized-based explosives by laser-induced breakdown spectroscopy.

    Science.gov (United States)

    Rezaei, Amir Hossein; Keshavarz, Mohammad Hossein; Tehrani, Masoud Kavosh; Reza Darbani, Seyyed Mohammad; Farhadian, Amir Hossein; Mousavi, Seyyed Jabbar; Mousaviazar, Ali

    2016-04-20

    Energetic materials containing aluminum powder are hazardous compounds, which have wide applications as propellants, explosives, and pyrotechnics. This work introduces a new method on the basis of the laser-induced breakdown spectroscopy technique in air and argon atmospheres to investigate determination of aluminum content and detonation performance of 1,3,5-trinitro-1,3,5-triazine (RDX)-based aluminized explosives. Plasma emission of aluminized RDX explosives are recorded where atomic lines of Al, C, H, N, and O, as well as molecular bands of AlO and CN are identified. The formation mechanism of AlO and CN molecular bands is affected by the aluminum percentage and oxygen content present in the composition and plasma. Relative intensity of the Al/O is used to determine detonation velocity and pressure of the RDX/Al samples. The released energy in the laser-induced plasma of aluminized RDX composition is related to the heat of explosion and percentage of aluminum.

  17. A pilot study on the vacuum degree online detection of vacuum interrupter using laser-induced breakdown spectroscopy

    Science.gov (United States)

    Wang, X. H.; Yuan, H.; Liu, D. X.; Yang, A. J.; Liu, P.; Gao, L.; Ding, H. B.; Wang, W. T.; Rong, M. Z.

    2016-11-01

    Vacuum degree online detection of vacuum interrupter has been a great challenge for decades. In this letter, a novel approach based on laser induced breakdown spectroscopy (LIBS) was proposed to solve this tough problem, which is suitable for non-intrusive, electro-magnetic interference free and remote detection. The spectral lines of Cu, H, N and O elements from the interrupter shield were detected for a large gas pressure range from p  =  1  ×  10-3 Pa to 1  ×  105 Pa. It was found that the spectral intensities of O and H increase monotonically with gas pressure, in contrast the spectral intensity of Cu first decreases slightly and then increases. Their intensity ratios, especially for that of Cu to O, change dramatically and monotonically with the gas pressure when p  ⩽  0.1 Pa, indicating that they can be used for determining the vacuum degree values. Spectral ratio method fundamentally reduces the influences of the possible variation in measuring distance and the laser power fluctuation, making LIBS a promising method for vacuum degree online detection of vacuum interrupters.

  18. Recent advances in the use of laser-induced breakdown spectroscopy (LIBS) as a rapid point-of-care pathogen diagnostic

    Science.gov (United States)

    Rehse, Steven J.; Miziolek, Andrzej W.

    2012-06-01

    Laser-induced breakdown spectroscopy (LIBS) has made tremendous progress in becoming a viable technology for rapid bacterial pathogen detection and identification. The significant advantages of LIBS include speed (sensitivity and specificity. Bacterial identifications are completely unaffected by environment, nutrition media, or state of growth and accurate diagnoses can be made on autoclaved or UV-irradiated specimens. Efficient discrimination of bacteria at the strain level has been demonstrated. A rapid urinary tract infection diagnosis has been simulated with no sample preparation and a one second diagnosis of a pathogen surrogate has been demonstrated using advanced chemometric analysis with a simple "stop-light" user interface. Stand-off bacterial identification at a 20-m distance has been demonstrated on a field-portable instrument. This technology could be implemented in doctors' offices, clinics, or hospital laboratories for point-of-care medical specimen analysis; mounted on military medical robotic platforms for in-the- field diagnostics; or used in stand-off configuration for remote sensing and detection.

  19. Examination of the capability of the laser-induced breakdown spectroscopy (LIBS) technique as the emerging laser-based analytical tool for analyzing trace elements in coal

    Science.gov (United States)

    Idris, N.; Ramli, M.; Mahidin, Hedwig, R.; Lie, Z. S.; Kurniawan, K. H.

    2014-09-01

    Due to its superior advantageous over the conventional analytical tools, laser-induced breakdown spectroscopy (LIBS) technique nowadays is becoming an emerging analytical tools and it is expected to be new future super star of analytical tool. This technique is based on the use of optical emission from the laser-induced plasma for analyzing spectrochemically the constituent and content of the sampled object. The capability of this technique is examined on analysis of trace elements in coal sample. Coal is one difficult sample to analyze due to its complex chemical composition and physical properties. It is inherent that coal contains trace element including heavy metal, thus mining, beneficiation and utilization poses hazard to environment and to human beings. The LIBS apparatus used was composed by a laser system (Nd-YAG: Quanta Ray; LAB SERIES; 1,064 nm; 500 mJ; 8 ns) and optical detector (McPherson model 2061; 1,000 mm focal length; f/8.6 Czerny-Turner) equipped with Andor I*Star intensified CCD 1024×256 pixels. The emitted laser was focused onto coal sample with a focusing lens of +250 mm. The plasma emission was collected by a fiber optics and sent to the the spectrograph. The coal samples were taken from Province of Aceh. As the results, several trace elements including heavy metal (As, Mn, Pb) can surely be observed, implying the eventuality of LIBS technique to analysis the presence of trace element in coal.

  20. First improvements in the detection and quantification of label-free nucleic acids by laser-induced breakdown spectroscopy: Application to the deoxyribonucleic acid micro-array technology

    Energy Technology Data Exchange (ETDEWEB)

    Le Meur, Julien [Laboratoire de Cancerologie Experimentale, Commissariat a l' Energie Atomique de Fontenay-aux-Roses, Direction des Sciences du Vivant, Departement de Radiobiologie et Radiopathologie, Fontenay-aux-Roses (France); Menut, Denis [Laboratoire de Reactivite des Surfaces et des Interfaces, Commissariat a l' Energie Atomique de Saclay, Direction de l' Energie Nucleaire, Departement de Physico-Chimie, Gif sur Yvette (France); Wodling, Pascal [Laboratoire d' Interaction Laser-Matiere, Commissariat a l' Energie Atomique de Saclay, Direction de l' Energie Nucleaire, Departement de Physico-Chimie, Gif sur Yvette (France); Salmon, Laurent [Laboratoire de Reactivite des Surfaces et des Interfaces, Commissariat a l' Energie Atomique de Saclay, Direction de l' Energie Nucleaire, Departement de Physico-Chimie, Gif sur Yvette (France); Thro, Pierre-Yves [Laboratoire d' Interaction Laser-Matiere, Commissariat a l' Energie Atomique de Saclay, Direction de l' Energie Nucleaire, Departement de Physico-Chimie, Gif sur Yvette (France); Chevillard, Sylvie [Laboratoire de Cancerologie Experimentale, Commissariat a l' Energie Atomique de Fontenay-aux-Roses, Direction des Sciences du Vivant, Departement de Radiobiologie et Radiopathologie, Fontenay-aux-Roses (France); Ugolin, Nicolas [Laboratoire de Cancerologie Experimentale, Commissariat a l' Energie Atomique de Fontenay-aux-Roses, Direction des Sciences du Vivant, Departement de Radiobiologie et Radiopathologie, Fontenay-aux-Roses (France)], E-mail: nugolin@cea.fr

    2008-04-15

    The accurate quantification of nucleic acids is essential in many fields of modern biology and industry, and in some cases requires the use of fluorescence labeling. Yet, in addition to standardization problems and quantification reproducibility, labeling can modify the physicochemical properties of molecules or affect their stability. To address these limitations, we have developed a novel method to detect and quantify label-free nucleic acids. This method is based on stoichiometric proportioning of phosphorus in the nucleic acid skeleton, using laser-induced breakdown spectroscopy, and a specific statistical analysis, which indicates the error probability for each measurement. The results obtained appear to be quantitative, with a limit of detection of 10{sup 5} nucleotides/{mu}m{sup 2} (i.e. 2 x 10{sup 13} phosphorus atoms/cm{sup 2}). Initial micro-array analysis has given very encouraging results, which point to new ways of quantifying hybridized nucleic acids. This is essential when comparing molecules of different sequences, which is presently very difficult with fluorescence labeling.

  1. Applications of High Resolution Laser Induced Breakdown Spectroscopy for Environmental and Biological Samples

    Energy Technology Data Exchange (ETDEWEB)

    Martin, Madhavi Z [ORNL; Labbe, Nicole [ORNL; Wagner, Rebekah J. [Pennsylvania State University, University Park, PA

    2013-01-01

    This chapter details the application of LIBS in a number of environmental areas of research such as carbon sequestration and climate change. LIBS has also been shown to be useful in other high resolution environmental applications for example, elemental mapping and detection of metals in plant materials. LIBS has also been used in phytoremediation applications. Other biological research involves a detailed understanding of wood chemistry response to precipitation variations and also to forest fires. A cross-section of Mountain pine (pinceae Pinus pungen Lamb.) was scanned using a translational stage to determine the differences in the chemical features both before and after a fire event. Consequently, by monitoring the elemental composition pattern of a tree and by looking for abrupt changes, one can reconstruct the disturbance history of a tree and a forest. Lastly we have shown that multivariate analysis of the LIBS data is necessary to standardize the analysis and correlate to other standard laboratory techniques. LIBS along with multivariate statistical analysis makes it a very powerful technology that can be transferred from laboratory to field applications with ease.

  2. Age-specific discrimination of blood plasma samples of healthy and ovarian cancer prone mice using laser-induced breakdown spectroscopy

    Science.gov (United States)

    Melikechi, Noureddine; Markushin, Yuri; Connolly, Denise C.; Lasue, Jeremie; Ewusi-Annan, Ebo; Makrogiannis, Sokratis

    2016-09-01

    Epithelial ovarian cancer (EOC) mortality rates are strongly correlated with the stage at which it is diagnosed. Detection of EOC prior to its dissemination from the site of origin is known to significantly improve the patient outcome. However, there are currently no effective methods for early detection of the most common and lethal subtype of EOC. We sought to determine whether laser-induced breakdown spectroscopy (LIBS) and classification techniques such as linear discriminant analysis (LDA) and random forest (RF) could classify and differentiate blood plasma specimens from transgenic mice with ovarian carcinoma and wild type control mice. Herein we report results using this approach to distinguish blood plasma samples obtained from serially bled (at 8, 12, and 16 weeks) tumor-bearing TgMISIIR-TAg transgenic and wild type cancer-free littermate control mice. We have calculated the age-specific accuracy of classification using 18,000 laser-induced breakdown spectra of the blood plasma samples from tumor-bearing mice and wild type controls. When the analysis is performed in the spectral range 250 nm to 680 nm using LDA, these are 76.7 (± 2.6)%, 71.2 (± 1.3)%, and 73.1 (± 1.4)%, for the 8, 12 and 16 weeks. When the RF classifier is used, we obtain values of 78.5 (± 2.3)%, 76.9 (± 2.1)% and 75.4 (± 2.0)% in the spectral range of 250 nm to 680 nm, and 81.0 (± 1.8)%, 80.4 (± 2.1)% and 79.6 (± 3.5)% in 220 nm to 850 nm. In addition, we report, the positive and negative predictive values of the classification of the two classes of blood plasma samples. The approach used in this study is rapid, requires only 5 μL of blood plasma, and is based on the use of unsupervised and widely accepted multivariate analysis algorithms. These findings suggest that LIBS and multivariate analysis may be a novel approach for detecting EOC.

  3. AVAILABILITY ANALYSIS OF THE QUEUEING SYSTEM GI/PH/1 WITH SERVER BREAKDOWNS

    Institute of Scientific and Technical Information of China (English)

    YUAN Xueming; LI Wei

    2003-01-01

    In the existing literature of Repairable Queueing Systems (RQS), i.e., queueing systems with server breakdowns, it is almost all assumed that interarrival times of successive customers are independent, identically exponentially distributed. In this paper, we deal with more generic system GI/PH/1 with server's exponential uptime and phase-type repair time. With matrix analysis theory, we establish the equilibrium condition and the characteristics of the system, derive the transient and stationary availability behavior of the system.

  4. Comparison of field portable measurements of ultrafine TiO2: X-ray fluorescence, laser-induced breakdown spectroscopy, and Fourier-transform infrared spectroscopy.

    Science.gov (United States)

    LeBouf, Ryan F; Miller, Arthur L; Stipe, Christopher; Brown, Jonathan; Murphy, Nate; Stefaniak, Aleksandr B

    2013-06-01

    Laboratory measurements of ultrafine titanium dioxide (TiO2) particulate matter loaded on filters were made using three field portable methods (X-ray fluorescence (XRF), laser-induced breakdown spectroscopy (LIBS), and Fourier-transform infrared (FTIR) spectroscopy) to assess their potential for determining end-of-shift exposure. Ultrafine TiO2 particles were aerosolized and collected onto 37 mm polycarbonate track-etched (PCTE) filters in the range of 3 to 578 μg titanium (Ti). Limit of detection (LOD), limit of quantification (LOQ), and calibration fit were determined for each measurement method. The LOD's were 11.8, 0.032, and 108 μg Ti per filter, for XRF, LIBS, and FTIR, respectively and the LOQ's were 39.2, 0.11, and 361 μg Ti per filter, respectively. The XRF calibration curve was linear over the widest dynamic range, up to the maximum loading tested (578 μg Ti per filter). LIBS was more sensitive but, due to the sample preparation method, the highest loaded filter measurable was 252 μg Ti per filter. XRF and LIBS had good predictability measured by regressing the predicted mass to the gravimetric mass on the filter. XRF and LIBS produced overestimations of 4% and 2%, respectively, with coefficients of determination (R(2)) of 0.995 and 0.998. FTIR measurements were less dependable due to interference from the PCTE filter media and overestimated mass by 2% with an R(2) of 0.831.

  5. A Comparative Study of Single-pulse and Double-pulse Laser-Induced Breakdown Spectroscopy with Uranium-containing Samples

    Energy Technology Data Exchange (ETDEWEB)

    Skrodzki, P. J.; Becker, J. R.; Diwakar, P. K.; Harilal, S. S.; Hassanein, A.

    2016-01-25

    Laser-induced breakdown spectroscopy (LIBS) holds potential advantages in special nuclear material (SNM) sensing and nuclear forensics which require rapid analysis, minimal sample preparation and stand-off distance capability. SNM, such as U, however, result in crowded emission spectra with LIBS, and characteristic emission lines are challenging to discern. It is well-known that double-pulse LIBS (DPLIBS) improves the signal intensity for analytes over conventional single-pulse LIBS (SPLIBS). This study investigates U signal in a glass matrix using DPLIBS and compares to signal features obtained using SPLIBS. DPLIBS involves sequential firing of 1.06 µm Nd:YAG pre-pulse and 10.6 µm TEA CO2 heating pulse in near collinear geometry. Optimization of experimental parameters including inter-pulse delay and energy follows identification of characteristic lines and signals for bulk analyte Ca and minor constituent analyte U for both DPLIBS and SPLIBS. Spatial and temporal coupling of the two pulses in the proposed DPLIBS technique yields improvements in analytical merits with negligible further damage to the sample compared to SPLIBS. Subsequently, the study discusses optimum plasma emission conditions of U lines and relative figures of merit in both SPLIBS and DPLIBS. Investigation into plasma characteristics also addresses plausible mechanisms related to observed U analyte signal variation between SPLIBS and DPLIBS.

  6. Multivariate approach to the chemical mapping of uranium in sandstone-hosted uranium ores analyzed using double pulse Laser-Induced Breakdown Spectroscopy

    Science.gov (United States)

    Klus, Jakub; Mikysek, Petr; Prochazka, David; Pořízka, Pavel; Prochazková, Petra; Novotný, Jan; Trojek, Tomáš; Novotný, Karel; Slobodník, Marek; Kaiser, Jozef

    2016-09-01

    The goal of this work is to provide high resolution mapping of uranium in sandstone-hosted uranium ores using Laser-Induced Breakdown Spectroscopy (LIBS) technique. In order to obtain chemical image with highest possible spatial resolution, LIBS system in orthogonal double pulse (DP LIBS) arrangement was employed. Owing to this experimental arrangement the spot size of 50 μm in diameter resulting in lateral resolution of 100 μm was reached. Despite the increase in signal intensity in DP LIBS modification, the detection of uranium is challenging. The main cause is the high density of uranium spectral lines, which together with broadening of LIBS spectral lines overreaches the resolution of commonly used spectrometers. It results in increased overall background radiation with only few distinguishable uranium lines. Three different approaches in the LIBS data treatment for the uranium detection were utilized: i) spectral line intensity, ii) region of apparent background and iii) multivariate data analysis. By utilizing multivariate statistical methods, a specific specimen features (in our case uranium content) were revealed by processing complete spectral information obtained from broadband echelle spectrograph. Our results are in a good agreement with conventional approaches such as line fitting and show new possibilities of processing spectral data in mapping. As a reference technique to LIBS was employed X-ray Fluorescence (XRF). The XRF chemical images used in this paper have lower resolution (approximately 1-2 mm per image point), nevertheless the elemental distribution is apparent and corresponds to presented LIBS experiments.

  7. The feasibility of liquid sample microanalysis using polydimethylsiloxane microfluidic chips with in-channel and in-port laser-induced breakdown spectroscopy detection

    Science.gov (United States)

    Metzinger, Anikó; Nagy, Andrea; Gáspár, Attila; Márton, Zsuzsanna; Kovács-Széles, Éva; Galbács, Gábor

    2016-12-01

    This study describes the direct interfacing of polydimethylsiloxane (PDMS) microfluidic chips with laser-induced breakdown spectroscopy (LIBS) detection. The changes induced in the PDMS material by nanosecond laser ablation are briefly documented by using optical microscopy and scanning profilometry. The main part of the study focuses on the solution of technical and analytical problems of coupling single-pulse LIBS detection with PDMS microfluidic chips in order to assess the feasibility and performance of the concept of creating a lab-on-a-chip device with LIBS detection (LOC-LIBS). Multiple optical and sample presentation schemes including in-channel and in-port detection were tested, but it was found that LOC-LIBS is only viable and practical with in-port detection outside the chip. It was shown that LOC-LIBS in this configuration is capable of the trace speciation analysis of chromium using as little as 0.5 μL solution volume. The achieved absolute limit of detection was 2 ng.

  8. A Comparative Study of Single-pulse and Double-pulse Laser-Induced Breakdown Spectroscopy with Uranium-containing Samples.

    Science.gov (United States)

    Skrodzki, Patrick J; Becker, Jason R; Diwakar, Prasoon K; Harilal, Sivanandan S; Hassanein, Ahmed

    2016-03-01

    Laser-induced breakdown spectroscopy (LIBS) holds potential advantages in special nuclear material (SNM) sensing and nuclear forensics, which require rapid analysis, minimal sample preparation, and stand-off distance capability. SNM, such as U, however, result in crowded emission spectra with LIBS, and characteristic emission lines are challenging to discern. It is well-known that double-pulse LIBS (DPLIBS) improves the signal intensity for analytes over conventional single-pulse LIBS (SPLIBS). This study investigates the U signal in a glass matrix using DPLIBS and compares it to signal obtained using SPLIBS. Double-pulse LIBS involves sequential firing of a 1.06 µm Nd:YAG pre-pulse and 10.6 µm TEA CO2 heating pulse in a near collinear geometry. Optimization of experimental parameters including inter-pulse delay and energy follows identification of characteristic lines for the bulk analyte Ca and the minor constituent analyte U for both DPLIBS and SPLIBS. Spatial and temporal coupling of the two pulses in the proposed DPLIBS technique yields improvements in analytical merits with a negligible increase in damage to the sample compared to SPLIBS. Subsequently, the study discusses optimum plasma emission conditions of U lines and relative figures of merit in both SPLIBS and DPLIBS. Investigation into plasma characteristics also addresses plausible mechanisms related to the observed U analyte signal variation between SPLIBS and DPLIBS.

  9. A partial least squares based spectrum normalization method for uncertainty reduction for laser-induced breakdown spectroscopy measurements

    Energy Technology Data Exchange (ETDEWEB)

    Li, Xiongwei [State Key Lab of Power Systems, Department of Thermal Engineering, Tsinghua-BP Clean Energy Center, Tsinghua University, Beijing (China); Wang, Zhe, E-mail: zhewang@tsinghua.edu.cn [State Key Lab of Power Systems, Department of Thermal Engineering, Tsinghua-BP Clean Energy Center, Tsinghua University, Beijing (China); Lui, Siu-Lung; Fu, Yangting; Li, Zheng [State Key Lab of Power Systems, Department of Thermal Engineering, Tsinghua-BP Clean Energy Center, Tsinghua University, Beijing (China); Liu, Jianming [China Guodian Science and Technology Research Institute, Nanjing 100034 (China); Ni, Weidou [State Key Lab of Power Systems, Department of Thermal Engineering, Tsinghua-BP Clean Energy Center, Tsinghua University, Beijing (China)

    2013-10-01

    A bottleneck of the wide commercial application of laser-induced breakdown spectroscopy (LIBS) technology is its relatively high measurement uncertainty. A partial least squares (PLS) based normalization method was proposed to improve pulse-to-pulse measurement precision for LIBS based on our previous spectrum standardization method. The proposed model utilized multi-line spectral information of the measured element and characterized the signal fluctuations due to the variation of plasma characteristic parameters (plasma temperature, electron number density, and total number density) for signal uncertainty reduction. The model was validated by the application of copper concentration prediction in 29 brass alloy samples. The results demonstrated an improvement on both measurement precision and accuracy over the generally applied normalization as well as our previously proposed simplified spectrum standardization method. The average relative standard deviation (RSD), average of the standard error (error bar), the coefficient of determination (R{sup 2}), the root-mean-square error of prediction (RMSEP), and average value of the maximum relative error (MRE) were 1.80%, 0.23%, 0.992, 1.30%, and 5.23%, respectively, while those for the generally applied spectral area normalization were 3.72%, 0.71%, 0.973, 1.98%, and 14.92%, respectively. - Highlights: • Multiple pairs of lines are used to compensate plasma temperature fluctuations. • Multi-line information is utilized to represent the elemental concentration. • Advantage of PLS algorithm is exploited by the model. • Both of uncertainty reduction and accuracy improvement are achieved.

  10. Onboard calibration igneous targets for the Mars Science Laboratory Curiosity rover and the Chemistry Camera laser induced breakdown spectroscopy instrument

    Energy Technology Data Exchange (ETDEWEB)

    Fabre, C., E-mail: cecile.fabre@g2r.uhp-nancy.fr [G2R, Nancy Universite (France); Maurice, S.; Cousin, A. [IRAP, Toulouse (France); Wiens, R.C. [LANL, Los Alamos, NM (United States); Forni, O. [IRAP, Toulouse (France); Sautter, V. [MNHN, Paris (France); Guillaume, D. [GET, Toulouse (France)

    2011-03-15

    Accurate characterization of the Chemistry Camera (ChemCam) laser-induced breakdown spectroscopy (LIBS) on-board composition targets is of prime importance for the ChemCam instrument. The Mars Science Laboratory (MSL) science and operations teams expect ChemCam to provide the first compositional results at remote distances (1.5-7 m) during the in situ analyses of the Martian surface starting in 2012. Thus, establishing LIBS reference spectra from appropriate calibration standards must be undertaken diligently. Considering the global mineralogy of the Martian surface, and the possible landing sites, three specific compositions of igneous targets have been determined. Picritic, noritic, and shergottic glasses have been produced, along with a Macusanite natural glass. A sample of each target will fly on the MSL Curiosity rover deck, 1.56 m from the ChemCam instrument, and duplicates are available on the ground. Duplicates are considered to be identical, as the relative standard deviation (RSD) of the composition dispersion is around 8%. Electronic microprobe and laser ablation inductively coupled plasma mass spectrometry (LA ICP-MS) analyses give evidence that the chemical composition of the four silicate targets is very homogeneous at microscopic scales larger than the instrument spot size, with RSD < 5% for concentration variations > 0.1 wt.% using electronic microprobe, and < 10% for concentration variations > 0.01 wt.% using LA ICP-MS. The LIBS campaign on the igneous targets performed under flight-like Mars conditions establishes reference spectra for the entire mission. The LIBS spectra between 240 and 900 nm are extremely rich, hundreds of lines with high signal-to-noise, and a dynamical range sufficient to identify unambiguously major, minor and trace elements. For instance, a first LIBS calibration curve has been established for strontium from [Sr] = 284 ppm to [Sr] = 1480 ppm, showing the potential for the future calibrations for other major or minor

  11. Double pulse laser-induced breakdown spectroscopy with femtosecond laser pulses

    Energy Technology Data Exchange (ETDEWEB)

    Pinon, V. [Institute of Electronic Structure and Laser, Foundation for Research and Technology-Hellas (IESL-FORTH), P.O. Box 1385, GR 71110 Heraklion, Crete (Greece); Universidad de A Coruna, Departamento de Ingenieria Industrial II, E-15403 Ferrol, A Coruna (Spain); Fotakis, C. [Institute of Electronic Structure and Laser, Foundation for Research and Technology-Hellas (IESL-FORTH), P.O. Box 1385, GR 71110 Heraklion, Crete (Greece); Nicolas, G. [Universidad de A Coruna, Departamento de Ingenieria Industrial II, E-15403 Ferrol, A Coruna (Spain); Anglos, D. [Institute of Electronic Structure and Laser, Foundation for Research and Technology-Hellas (IESL-FORTH), P.O. Box 1385, GR 71110 Heraklion, Crete (Greece)], E-mail: anglos@iesl.forth.gr

    2008-10-15

    This paper presents results obtained in a study of collinear geometry double pulse femtosecond LIBS analysis of solids in ambient environment. LIBS signal enhancement of 3-10 fold, accompanied by significant improvement of signal reproducibility, in comparison with the single pulse case, has been found in different samples such as brass, iron, silicon, barium sulfate and aluminum when an optimum temporal separation between the two ablating pulses is used. The influence of the delay between pulses in the LIBS signal intensity was investigated and two intervals of interaction were established. A first transient regime from 0 to 50 ps, in which the LIBS signal increases until reaching a maximum, and a second regime that ranges from 50 to 1000 ps (maximum inter-pulse delay investigated) in which the signal enhancement remains constant. Emissions from both ionized and neutral atoms show the same pattern of enhancement with a clear tendency of lines arising from higher energy emissive states to exhibit higher enhancement factors.

  12. Biological application of laser induced breakdown spectroscopy technique for determination of trace elements in hair.

    Science.gov (United States)

    Emara, Elshaimaa M; Imam, Hisham; Hassan, Mouyed A; Elnaby, Salah H

    2013-12-15

    Analysis of trace elements in mammalian hair has the potential to reveal retrospective information about an individual's nutritional status and exposure. As trace elements are incorporated into the hair during the growth process, longitudinal segments of the hair may reflect the body burden during growth. Using LIBS technique, Na, K, Ca, Mg, Si, Fe, Pb and Zn were detected in a single strand of horse hair. The results obtained through LIBS technique on hair samples were compared with the traditional technique (AAS) on digested acidified solution of the same samples. The effects of the experimental parameters on the emission lines were studied and the local thermodynamic equilibrium (LTE) in produced plasma was investigated. The transient plasma condition was verified at specific time region (1500-2000 ns) in the plasma evolution corresponding to its dynamic expanding characteristic. The relative mass concentrations of Fe and Zn were calculated by setting the concentration of C as the calibration. The information obtained from the trace elements' spectra of horse hair in this study substantiates the potential of hair as a biomarker.

  13. Influence of oxygen addition to the carrier gas on laser-induced breakdown spectroscopy measurements on aerosols

    Science.gov (United States)

    Palazzo, N.; Migliorini, F.; Dondè, R.; Maffi, S.; De Iuliis, S.

    2016-01-01

    In this work, laser-induced breakdown spectrosopy is implemented on aerosol particles for absolute concentration analysis. The aim of this work is the investigation of the effect of the bath gas used for nebulizing the aerosol. Nitrogen, air, and 50% O2 in N2 mixture have been chosen as carrier gasses in order to analyze the effect of oxygen addition to the gas. LIBS measurements have been carried out on aerosol particles produced from CuCl2 2H2O solutions, and the 324.7 nm Cu line is considered. As a first analysis, plasma parameters, such as temperature and electron density, have been evaluated changing the carrier gas. Measurements to derive the LIBS calibration curve of the 324.7 nm Cu line are carried out in air and in N2. The significant difference in the slope of the resulting calibration curves has to be attributed to the oxygen addition to the bath gas. To explore such behavior, time-resolved measurements of the Cu line and peak/base ratio have been performed. The presence of two competitive effects have been observed that becomes significant increasing the amount of oxygen in the carrier gas. One is the oxygen-quenching effect, already observed in the literature, and the other one is the enhancement of the Cu LIBS signal, expecially at short delay times. These effects have been observed also at other Cu lines and changing the analyte source. The results are presented and widely discussed.

  14. Fast-imaging and spectroscopic analysis of atmospheric argon streamers for large gap arc breakdown

    Science.gov (United States)

    Pachuilo, Michael; Stefani, Francis; Bengtson, Roger; Raja, Laxminarayan

    2014-10-01

    A non-equilibrium plasma source has been developed to assist in the low-voltage arc breakdown of large electrode gaps. The source consists of a dielectric embedded wire helically wound around a confining cylindrical quartz chamber. Annular electrodes cap the ends of the quartz chamber. An argon feed gas is used to provide a uniform environment and exhausts to ambient atmospheric conditions. A negative polarity 50 kV trigger pulse is applied to the embedded trigger wire to initiate the arc breakdown. Application of the trigger pulse produces a localized coronal discharges along the inner surface of the quartz tube. The corona provides seed electrons through which streamers propagate from one of the main discharge electrode along the quartz surface until it reaches the opposite electrode to bridge the gap. Once the gap is bridged a spark over occurs and robust arc discharge is formed in the chamber volume. Fast imaging of the streamer propagation establishes its velocity in the range of ~ 100 km/s. Spectroscopy of the streamer discharge in atmospheric argon has been conducted and electron temperature and number density estimated from a collision radiative model. Argon spectrum is dominated by neutral argon lines in the 650--950 nm range, and singly ionized argon lines are observed in the ultra-violet to near UV (300--400 nm). Research was performed in connection with AFOSR Contract FA9550-11-1-0062.

  15. Numerical analysis of excimer laser-induced breakdown of Kr gas

    Science.gov (United States)

    Hamam, Kholoud A.; Elsayed, Khaled A.; Gamal, Yosr E. E.

    2017-03-01

    The present paper displays a numerical study on the role of electron dynamics in relation to the dependence of the threshold intensity on the pressure in the breakdown of gases by laser radiation. The analysis aimed to find out the origin of the steep slope observed in the measurements of threshold intensity against gas pressure in the breakdown of Kr induced by an excimer laser source (Opt. Commun. 13:66-68, 1). The experiment was carried out using wavelength 248 nm and pulse width of 18 ns for a gas pressure range 4.5-300 torr. The investigation centered on an adaptation of our previously developed electron cascade model given in Evans and Gamal (J. Phys. D Appl. Phys. 13:1447-1458, 2). This model solves numerically a time-dependent energy equation simultaneously with a set of rate equations that describe the change of the population of the formed excited states. The modifications introduced into the model the realistic structure of the krypton gas atom as well as electron diffusion as a loss process to inspect the experimentally tested low-pressure regime. A computer program is undertaken to determine the breakdown threshold intensity as a function of gas pressure. Reasonable agreement is obtained between the calculated thresholds and measured ones, corresponding to the examined pressure range. This agreement validates the applicability of the model. The relationship between the role of the physical mechanisms and gas pressure is studied by analyzing the EEDF and its parameters at selected pressure values that cover the experimentally tested range. The result of this study clarified that electron diffusion out of the focal region is responsible for the steep slope of the threshold intensities for pressures values showed non-Maxwellian distribution as well as determined the time and energy region at which breakdown is formed.

  16. Development of Calibration-Free Laser-Induced-Breakdown-Spectroscopy based techniques for deposited layers diagnostics on ITER-like tiles

    Energy Technology Data Exchange (ETDEWEB)

    Fantoni, Roberta [ENEA, UTAPRAD, V. E. Fermi 45, 00044 Frascati (Italy); Almaviva, Salvatore, E-mail: salvatore.almaviva@enea.it [ENEA, UTAPRAD, V. E. Fermi 45, 00044 Frascati (Italy); Caneve, Luisa; Colao, Francesco [ENEA, UTAPRAD, V. E. Fermi 45, 00044 Frascati (Italy); Popov, Andrey M. [Chemistry Department, M.V. Lomonosov Moscow State University, Moscow (Russian Federation); Maddaluno, Giorgio [Assoc. ENEA-EURATOM sulla Fusione, V. E. Fermi 45, 00044 Frascati (Italy)

    2013-09-01

    High temperature plasma in hydrogen isotopes is peculiar of thermonuclear fusion devices. The study of plasma–wall interaction is of paramount importance for avoiding both damage of plasma facing components (PFCs) and pollution of the plasma. To assure continuous and fault-free operation a strict control must be exerted on the amount of impurities deposited on, and of the fuel retained in the PFCs. This requirement makes Laser-Induced-Breakdown-Spectroscopy (LIBS) an ideal candidate for on-line quantitative monitoring of the walls of the current as well as of the next generation fusion devices like the International Thermonuclear Experimental Reactor (ITER). An experimental setup has been designed and realized in order to optimize the characteristics of a LIBS system working at low pressure and remotely, and it has been utilized in combination with calibration free procedures for quantitative analysis. In this work, a partial calibration free method has been developed for single shot analysis of hydrogen isotopes retention at the PFCs-like surfaces, based on the acquisition of high resolution spectra in a narrow wavelength range. Results of calibration free and partial calibration free have been obtained on suitably deuterated samples; preliminary spectroscopic considerations on tritium detection are also presented. - Highlights: • LIBS system “in situ” and remote for new generation fusion machines • Atomic composition of plasma facing component samples in fusion machines • Calibration free method for a qualitative/quantitative analysis is discussed. • Description of a new simplified calibration free method (partial calibration free) • LIBS for screening erosion/redeposition during operation of fusion machines.

  17. Blood analysis by Raman spectroscopy

    Science.gov (United States)

    Enejder, Annika M. K.; Koo, Tae-Woong; Oh, Jeankun; Hunter, Martin; Sasic, Slobodan; Feld, Michael S.; Horowitz, Gary L.

    2002-11-01

    Concentrations of multiple analytes were simultaneously measured in whole blood with clinical accuracy, without sample processing, using near-infrared Raman spectroscopy. Spectra were acquired with an instrument employing nonimaging optics, designed using Monte Carlo simulations of the influence of light-scattering-absorbing blood cells on the excitation and emission of Raman light in turbid medium. Raman spectra were collected from whole blood drawn from 31 individuals. Quantitative predictions of glucose, urea, total protein, albumin, triglycerides, hematocrit, and hemoglobin were made by means of partial least-squares (PLS) analysis with clinically relevant precision (r2 values >0.93). The similarity of the features of the PLS calibration spectra to those of the respective analyte spectra illustrates that the predictions are based on molecular information carried by the Raman light. This demonstrates the feasibility of using Raman spectroscopy for quantitative measurements of biomolecular contents in highly light-scattering and absorbing media.

  18. Detection of rare earth elements in Powder River Basin sub-bituminous coal ash using laser-induced breakdown spectroscopy (LIBS)

    Energy Technology Data Exchange (ETDEWEB)

    Tran, Phuoc [National Energy Technology Lab. (NETL), Pittsburgh, PA, (United State; Mcintyre, Dustin [National Energy Technology Lab. (NETL), Pittsburgh, PA, (United State

    2015-10-01

    We reported our preliminary results on the use of laser-induced breakdown spectroscopy to analyze the rare earth elements contained in ash samples from Powder River Basin sub-bituminous coal (PRB-coal). We have identified many elements in the lanthanide series (cerium, europium, holmium, lanthanum, lutetium, praseodymium, promethium, samarium, terbium, ytterbium) and some elements in the actinide series (actinium, thorium, uranium, plutonium, berkelium, californium) in the ash samples. In addition, various metals were also seen to present in the ash samples

  19. Applications of ultra-short pulsed laser ablation: thin films deposition and fs/ns dual-pulse laser-induced breakdown spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Teghil, R; De Bonis, A; Galasso, A [Dipartimento di Chimica, Universita della Basilicata, Via N. Sauro 85, 85100 Potenza (Italy); Santagata, A; Albano, G; Villani, P; Spera, D; Parisi, G P [CNR-IMIP, Unita di Potenza, Via S. Loja, 85050 Tito Scalo (Italy)], E-mail: roberto.teghil@unibas.it

    2008-10-15

    In this paper, we report a survey of two of the large number of possible practical applications of the laser ablation performed by an ultra-short pulse laser, namely pulsed laser deposition (PLD) and fs/ns dual-pulse laser-induced breakdown spectroscopy (DP-LIBS). These applications differ from those using just longer pulsed lasers as a consequence of the distinctive characteristics of the plasma produced by ultra-short laser beams. The most important feature of this plasma is the large presence of particles with nanometric size which plays a fundamental role in both applications.

  20. Mapping of lead, magnesium and copper accumulation in plant tissues by laser-induced breakdown spectroscopy and laser-ablation inductively coupled plasma mass spectrometry

    Science.gov (United States)

    Kaiser, J.; Galiová, M.; Novotný, K.; Červenka, R.; Reale, L.; Novotný, J.; Liška, M.; Samek, O.; Kanický, V.; Hrdlička, A.; Stejskal, K.; Adam, V.; Kizek, R.

    2009-01-01

    Laser-Induced Breakdown Spectroscopy (LIBS) and Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) were utilized for mapping the accumulation of Pb, Mg and Cu with a resolution up to 200 μm in a up to cm × cm area of sunflower ( Helianthus annuus L.) leaves. The results obtained by LIBS and LA-ICP-MS are compared with the outcomes from Atomic Absorption Spectrometry (AAS) and Thin-Layer Chromatography (TLC). It is shown that laser-ablation based analytical methods can substitute or supplement these techniques mainly in the cases when a fast multi-elemental mapping of a large sample area is needed.

  1. Mapping of lead, magnesium and copper accumulation in plant tissues by laser-induced breakdown spectroscopy and laser-ablation inductively coupled plasma mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Kaiser, J. [Institute of Physical Engineering, Faculty of Mechanical Engineering, Brno University of Technology, Technicka 2896/2, 616 69 Brno (Czech Republic)], E-mail: kaiser@fme.vutbr.cz; Galiova, M.; Novotny, K.; Cervenka, R. [Department of Chemistry, Faculty of Science, Masaryk University, Kotlarska 2, 611 37 Brno (Czech Republic); Reale, L. [Faculty of Sciences, University of L' Aquila, Via Vetoio (Coppito 1), 67010 L' Aquila (Italy); Novotny, J.; Liska, M.; Samek, O. [Institute of Physical Engineering, Faculty of Mechanical Engineering, Brno University of Technology, Technicka 2896/2, 616 69 Brno (Czech Republic); Kanicky, V.; Hrdlicka, A. [Department of Chemistry, Faculty of Science, Masaryk University, Kotlarska 2, 611 37 Brno (Czech Republic); Stejskal, K.; Adam, V.; Kizek, R. [Department of Chemistry and Biochemistry, Faculty of Agronomy, Mendel University of Agriculture and Forestry, Zemedelska 1, 613 00 Brno (Czech Republic)

    2009-01-15

    Laser-Induced Breakdown Spectroscopy (LIBS) and Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) were utilized for mapping the accumulation of Pb, Mg and Cu with a resolution up to 200 {mu}m in a up to cm x cm area of sunflower (Helianthus annuus L.) leaves. The results obtained by LIBS and LA-ICP-MS are compared with the outcomes from Atomic Absorption Spectrometry (AAS) and Thin-Layer Chromatography (TLC). It is shown that laser-ablation based analytical methods can substitute or supplement these techniques mainly in the cases when a fast multi-elemental mapping of a large sample area is needed.

  2. Quantitative measurement of Au and Fe in ferromagnetic nanoparticles with Laser Induced Breakdown Spectroscopy using a polymer-based gel matrix

    Energy Technology Data Exchange (ETDEWEB)

    Borowik, T., E-mail: tomasz.borowik@pwr.wroc.pl [Laboratory for Biophysics of Macromolecular Aggregates, Institute of Biomedical Engineering and Measurements, Wroclaw Technical University, Wroclaw, Pl. Grunwaldzki 13 (Poland); Przybylo, M., E-mail: magdalena.przybylo@pwr.wroc.pl [Laboratory for Biophysics of Macromolecular Aggregates, Institute of Biomedical Engineering and Measurements, Wroclaw Technical University, Wroclaw, Pl. Grunwaldzki 13 (Poland); Pala, K., E-mail: pala@protein.pl [Department of Protein Engineering, Faculty of Biotechnology, University of Wroclaw Tamka 2, 50-137 (Poland); Otlewski, J., E-mail: otlewski@protein.pl [Department of Protein Engineering, Faculty of Biotechnology, University of Wroclaw Tamka 2, 50-137 (Poland); Langner, M., E-mail: marek.langner@pwr.wroc.pl [Laboratory for Biophysics of Macromolecular Aggregates, Institute of Biomedical Engineering and Measurements, Wroclaw Technical University, Wroclaw, Pl. Grunwaldzki 13 (Poland)

    2011-09-15

    The medical applications of nanomaterials require substantial changes in the research and development stage, such as the introduction of new processes and methods, and adequate modifications of the national and international laws on the medical product registration. To accomplish this, proper parameterizations of nano-scaled products need to be developed and implemented, accompanied by suitable measuring methods. The introduction of metallic particles to medical practices requires the precise, quantitative evaluation of the production process and later quantification and characterization of the nanoparticles in biological matrices for the bioavailability and biodistribution evaluation. In order to address these issues we propose a method for the quantitative analysis of the metallic nanoparticles composition by Laser Induced Breakdown Spectroscopy (LIBS). Au/Fe ferro-magnetic nanoparticles were used to evaluate the method applicability. Since the powder form of nanoparticles spatters upon laser ablation, first we had to develop fast, convenient and quantitative method for the nano-powdered sample preparation. The proposed method is based on the polymer gelation of nanopowders or their water suspensions. It has been shown that nanopowders compositional changes throughout the production process, along with their final characterization, can be reliable performed with LIBS technique. The quantitative values obtained were successfully correlated with those derived with ICP technique. - Highlights: Black-Right-Pointing-Pointer The atomic composition of nanoparticles was analyzed with LIBS. Black-Right-Pointing-Pointer The amount of gold on ferromagnetic particles was quantified by the method. Black-Right-Pointing-Pointer Gel fixation was used as new way of handling powdered samples. Black-Right-Pointing-Pointer LIBS results are comparable with other equivalent methods (ICP). Black-Right-Pointing-Pointer There was a difference between measured and assumed nanoparticle

  3. Cropland Field Monitoring: MMV Page 1 Montana Cropland Enrolled Farm Fields Carbon Sequestration Field Sampling, Measurement, Monitoring, and Verification: Application of Visible-Near Infrared Diffuse Reflectance Spectroscopy (VNIR) and Laser-induced Breakdown Spectroscopy (LIBS)

    Energy Technology Data Exchange (ETDEWEB)

    Lee Spangler; Ross Bricklemyer; David Brown

    2012-03-15

    There is growing need for rapid, accurate, and inexpensive methods to measure, and verify soil organic carbon (SOC) change for national greenhouse gas accounting and the development of a soil carbon trading market. Laboratory based soil characterization typically requires significant soil processing, which is time and resource intensive. This severely limits application for large-region soil characterization. Thus, development of rapid and accurate methods for characterizing soils are needed to map soil properties for precision agriculture applications, improve regional and global soil carbon (C) stock and flux estimates and efficiently map sub-surface metal contamination, among others. The greatest gains for efficient soil characterization will come from collecting soil data in situ, thus minimizing soil sample transportation, processing, and lab-based measurement costs. Visible and near-infrared diffuse reflectance spectroscopy (VisNIR) and laser-induced breakdown spectroscopy (LIBS) are two complementary, yet fundamentally different spectroscopic techniques that have the potential to meet this need. These sensors have the potential to be mounted on a soil penetrometer and deployed for rapid soil profile characterization at field and landscape scales. Details of sensor interaction, efficient data management, and appropriate statistical analysis techniques for model calibrations are first needed. In situ or on-the-go VisNIR spectroscopy has been proposed as a rapid and inexpensive tool for intensively mapping soil texture and organic carbon (SOC). While lab-based VisNIR has been established as a viable technique for estimating various soil properties, few experiments have compared the predictive accuracy of on-the-go and lab-based VisNIR. Eight north central Montana wheat fields were intensively interrogated using on-the-go and lab-based VisNIR. Lab-based spectral data consistently provided more accurate predictions than on-the-go data. However, neither in situ

  4. Direct determination of Ti content in sunscreens with laser-induced breakdown spectroscopy: Line selection method for high TiO{sub 2} nanoparticle concentration

    Energy Technology Data Exchange (ETDEWEB)

    Menneveux, Jérôme; Wang, Fang; Lu, Shan; Bai, Xueshi; Motto-Ros, Vincent [Institut Lumière Matière, UMR5306 Université Lyon 1-CNRS, Université de Lyon, 69622 Villeurbanne Cedex (France); Gilon, Nicole [Institut des Sciences Analytiques, UMR5280 Université Lyon 1-CNRS, Université de Lyon, 69622 Villeurbanne Cedex (France); Chen, Yanping [Department of Physics and Astrophysics, Shanghai Jiao Tong University, Shanghai 200240 (China); Yu, Jin, E-mail: jin.yu@univ-lyon1.fr [Institut Lumière Matière, UMR5306 Université Lyon 1-CNRS, Université de Lyon, 69622 Villeurbanne Cedex (France); Department of Physics and Astrophysics, Shanghai Jiao Tong University, Shanghai 200240 (China)

    2015-07-01

    Sunscreen represents a large variety of creams which, in the analytical point of view, exhibit a similar matrix. Such matrix corresponds to a semi-solid emulsion of mixture of oil and water. The formulation of a cream can include metal and nonmetal elements in different contents in order to realize specific pharmaceutical or cosmetic functions designed for the product. The complex matrix of these materials makes their analysis challenging for classical elemental analytical techniques with specific and complicated sample pretreatment procedures needed for reliable quantification. In this work we demonstrate and assess direct determination, without any pretreatment, of elemental content, especially for metallic element such as titanium, in a sunscreen using laser-induced breakdown spectroscopy (LIBS). The used configuration corresponds to that of indirect ablation of a thin film of cream applied on the surface of a pure aluminum target. We especially focused, in this work, on the case of high concentration of TiO{sub 2} nanoparticle in cream. Such choice was justified first by the fact that such concentration level is usually found in commercial sunscreens. On the other hand, titanium presents a large number of lines, neutral as well as singly ionized, in the spectral range from the near UV to the near IR. It provides therefore an ideal case to study line selection method to manage the effect of self-absorption, which becomes unavoidable at high concentration level, and to optimize measurement precision. Through such study, we try to deduce a quantifiable and generalizable line selection method for high performance LIBS measurements. More specifically, calibration curves were first established using 6 laboratory-prepared samples. The quadratic term of the curves was then studied as a function of the intensity of the used lines and their type (neutral or ion, resonant or non-resonant). The prediction performance of the lines was assessed with 2 validation samples with

  5. Reliability analysis of M/G/1 queues with general retrial times and server breakdowns

    Institute of Scientific and Technical Information of China (English)

    WANG Jinting

    2006-01-01

    This paper concerns the reliability issues as well as queueing analysis of M/G/1 retrial queues with general retrial times and server subject to breakdowns and repairs. We assume that the server is unreliable and customers who find the server busy or down are queued in the retrial orbit in accordance with a first-come-first-served discipline. Only the customer at the head of the orbit queue is allowed for access to the server. The necessary and sufficient condition for the system to be stable is given. Using a supplementary variable method, we obtain the Laplace-Stieltjes transform of the reliability function of the server and a steady state solution for both queueing and reliability measures of interest. Some main reliability indexes, such as the availability, failure frequency, and the reliability function of the server, are obtained.

  6. Experimental and theoretical analysis of vortex breakdown in the wake of the 25∘ Ahmed body

    Science.gov (United States)

    Jermann, Cyril; Meliga, Philippe; Pujals, Gregory; Gallaire, Francois; Serre, Eric

    2014-11-01

    We study experimentally and theoretically the wake of the 25circ; Ahmed body, considered a suitable test-case to reproduce the two counter-rotating longitudinal vortices widely encountered in automotive aerodynamics. The three-dimensional experimental mean flow is reconstructed at high Reynolds number (Re = 2 . 8 ×106) from a series of cross-flow time-averaged planes acquired with a moving automated Stereo-PIV system. We observe a sharp decay of the axial velocity and vorticity in the near-wake, 0 . 5 times the projected length of the slanted surface downstream the square back, where the streamwise vortices is subjected to a strong adverse pressure gradient and the turbulent kinetic energy exhibits a peak in the vortex core. A stability analysis of the experimental velocity shows that the flow undergoes vortex breakdown roughly at the same position, through a transition from supercritical (x 0 . 5) conditions and the accumulation of upstream propagating axisymmetric waves.

  7. Non-adiabatic effects in thermochemistry, spectroscopy and kinetics: the general importance of all three Born-Oppenheimer breakdown corrections.

    Science.gov (United States)

    Reimers, Jeffrey R; McKemmish, Laura K; McKenzie, Ross H; Hush, Noel S

    2015-10-14

    Using a simple model Hamiltonian, the three correction terms for Born-Oppenheimer (BO) breakdown, the adiabatic diagonal correction (DC), the first-derivative momentum non-adiabatic correction (FD), and the second-derivative kinetic-energy non-adiabatic correction (SD), are shown to all contribute to thermodynamic and spectroscopic properties as well as to thermal non-diabatic chemical reaction rates. While DC often accounts for >80% of thermodynamic and spectroscopic property changes, the commonly used practice of including only the FD correction in kinetics calculations is rarely found to be adequate. For electron-transfer reactions not in the inverted region, the common physical picture that diabatic processes occur because of surface hopping at the transition state is proven inadequate as the DC acts first to block access, increasing the transition state energy by (ℏω)(2)λ/16J(2) (where λ is the reorganization energy, J the electronic coupling and ω the vibration frequency). However, the rate constant in the weakly-coupled Golden-Rule limit is identified as being only inversely proportional to this change rather than exponentially damped, owing to the effects of tunneling and surface hopping. Such weakly-coupled long-range electron-transfer processes should therefore not be described as "non-adiabatic" processes as they are easily described by Born-Huang ground-state adiabatic surfaces made by adding the DC to the BO surfaces; instead, they should be called just "non-Born-Oppenheimer" processes. The model system studied consists of two diabatic harmonic potential-energy surfaces coupled linearly through a single vibration, the "two-site Holstein model". Analytical expressions are derived for the BO breakdown terms, and the model is solved over a large parameter space focusing on both the lowest-energy spectroscopic transitions and the quantum dynamics of coherent-state wavepackets. BO breakdown is investigated pertinent to: ammonia inversion, aromaticity

  8. Comparison of partial least squares and lasso regression techniques as applied to laser-induced breakdown spectroscopy of geological samples

    Energy Technology Data Exchange (ETDEWEB)

    Dyar, M.D., E-mail: mdyar@mtholyoke.edu [Dept. of Astronomy, Mount Holyoke College, 50 College St., South Hadley, MA 01075 (United States); Carmosino, M.L.; Breves, E.A.; Ozanne, M.V. [Dept. of Astronomy, Mount Holyoke College, 50 College St., South Hadley, MA 01075 (United States); Clegg, S.M.; Wiens, R.C. [Los Alamos National Laboratory, P.O. Box 1663, MS J565, Los Alamos, NM 87545 (United States)

    2012-04-15

    A remote laser-induced breakdown spectrometer (LIBS) designed to simulate the ChemCam instrument on the Mars Science Laboratory Rover Curiosity was used to probe 100 geologic samples at a 9-m standoff distance. ChemCam consists of an integrated remote LIBS instrument that will probe samples up to 7 m from the mast of the rover and a remote micro-imager (RMI) that will record context images. The elemental compositions of 100 igneous and highly-metamorphosed rocks are determined with LIBS using three variations of multivariate analysis, with a goal of improving the analytical accuracy. Two forms of partial least squares (PLS) regression are employed with finely-tuned parameters: PLS-1 regresses a single response variable (elemental concentration) against the observation variables (spectra, or intensity at each of 6144 spectrometer channels), while PLS-2 simultaneously regresses multiple response variables (concentrations of the ten major elements in rocks) against the observation predictor variables, taking advantage of natural correlations between elements. Those results are contrasted with those from the multivariate regression technique of the least absolute shrinkage and selection operator (lasso), which is a penalized shrunken regression method that selects the specific channels for each element that explain the most variance in the concentration of that element. To make this comparison, we use results of cross-validation and of held-out testing, and employ unscaled and uncentered spectral intensity data because all of the input variables are already in the same units. Results demonstrate that the lasso, PLS-1, and PLS-2 all yield comparable results in terms of accuracy for this dataset. However, the interpretability of these methods differs greatly in terms of fundamental understanding of LIBS emissions. PLS techniques generate principal components, linear combinations of intensities at any number of spectrometer channels, which explain as much variance in the

  9. Comparison of partial least squares and lasso regression techniques as applied to laser-induced breakdown spectroscopy of geological samples

    Science.gov (United States)

    Dyar, M. D.; Carmosino, M. L.; Breves, E. A.; Ozanne, M. V.; Clegg, S. M.; Wiens, R. C.

    2012-04-01

    A remote laser-induced breakdown spectrometer (LIBS) designed to simulate the ChemCam instrument on the Mars Science Laboratory Rover Curiosity was used to probe 100 geologic samples at a 9-m standoff distance. ChemCam consists of an integrated remote LIBS instrument that will probe samples up to 7 m from the mast of the rover and a remote micro-imager (RMI) that will record context images. The elemental compositions of 100 igneous and highly-metamorphosed rocks are determined with LIBS using three variations of multivariate analysis, with a goal of improving the analytical accuracy. Two forms of partial least squares (PLS) regression are employed with finely-tuned parameters: PLS-1 regresses a single response variable (elemental concentration) against the observation variables (spectra, or intensity at each of 6144 spectrometer channels), while PLS-2 simultaneously regresses multiple response variables (concentrations of the ten major elements in rocks) against the observation predictor variables, taking advantage of natural correlations between elements. Those results are contrasted with those from the multivariate regression technique of the least absolute shrinkage and selection operator (lasso), which is a penalized shrunken regression method that selects the specific channels for each element that explain the most variance in the concentration of that element. To make this comparison, we use results of cross-validation and of held-out testing, and employ unscaled and uncentered spectral intensity data because all of the input variables are already in the same units. Results demonstrate that the lasso, PLS-1, and PLS-2 all yield comparable results in terms of accuracy for this dataset. However, the interpretability of these methods differs greatly in terms of fundamental understanding of LIBS emissions. PLS techniques generate principal components, linear combinations of intensities at any number of spectrometer channels, which explain as much variance in the

  10. Detection of the level of fluoride in the commercially available toothpaste using laser induced breakdown spectroscopy with the marker atomic transition line of neutral fluorine at 731.1 nm

    Science.gov (United States)

    Gondal, M. A.; Maganda, Y. W.; Dastageer, M. A.; Al Adel, F. F.; Naqvi, A. A.; Qahtan, T. F.

    2014-04-01

    Fourth harmonic of a pulsed Nd:YAG laser (wavelength 266 nm) in combination with high resolution spectrograph equipped with Gated ICCD camera has been employed to design a high sensitive analytical system. This detection system is based on Laser Induced Breakdown Spectroscopy and has been tested first time for analysis of semi-fluid samples to detect fluoride content present in the commercially available toothpaste samples. The experimental parameters were optimized to achieve an optically thin and in local thermo dynamic equilibrium plasma. This improved the limits of detection of fluoride present in tooth paste samples. The strong atomic transition line of fluorine at 731.102 nm was used as the marker line to quantify the fluoride concentration levels. Our LIBS system was able to detect fluoride concentration levels in the range of 1300-1750 ppm with a detection limit of 156 ppm.

  11. The Analysis of Insulation Breakdown Probabilities by the Up-And-Down Method

    DEFF Research Database (Denmark)

    Vibholm (fratrådt), Svend; Thyregod, Poul

    1986-01-01

    This paper discusses the assessment of breakdown probability by means of the up-and-down method. The Dixon and Mood approximation to the maximum-likelihood estimate is compared with the exact maximum-likelihood estimate for a number of response patterns. Estimates of the 50D probability breakdown...

  12. Latest development of laser induced breakdown spectroscopy%激光诱导击穿光谱技术研究的新进展

    Institute of Scientific and Technical Information of China (English)

    刘佳; 高勋; 段花花; 林景全

    2012-01-01

    Laser-induced breakdown spectroscopy(LIBS) is a technique based on atomic spectroscopy for the analysis of the elementary composition and concentration of materials.With the development of laser technique and optical detection technique,LIBS has become a focus in the spectrometric field.Particularly in recent years,LIBS technique develops very quickly.There emerge many new excitation and detection techniques of LIBS.At the aspect of plasma excitation;there are femtosecond-LIBS,filamentation LIBS,and dual pulse LIBS.At the aspect of spectral detection;there are time-resolved LIBS and polarization-resolved LIBS.This paper gives a review of these new LIBS techniques.%激光诱导击穿光谱技术(LIBS)是一种基于原子发射光谱学的物质组分分析技术。随着激光技术和光学检测技术的发展,激光诱导击穿光谱技术已经成为光谱学领域的研究热点。尤其是近几年,LIBS技术发展迅速,涌现出多种LIBS的激发和探测新技术。在光谱激发方面,出现了如飞秒激光及飞秒激光大气中长距离成丝诱导击穿光谱技术,双脉冲激光诱导击穿光谱技术等。在光谱探测方面,出现了时间分辨激光诱导击穿光谱技术,偏振分辨激光诱导击穿光谱技术等。本文将对这几种LIBS中所出现的新技术进行介绍并给出LIBS技术的发展趋势。

  13. Quantitative statistical analysis of dielectric breakdown in zirconia-based self-assembled nanodielectrics.

    Science.gov (United States)

    Schlitz, Ruth A; Ha, Young-geun; Marks, Tobin J; Lauhon, Lincoln J

    2012-05-22

    Uniformity of the dielectric breakdown voltage distribution for several thicknesses of a zirconia-based self-assembled nanodielectric was characterized using the Weibull distribution. Two regimes of breakdown behavior are observed: self-assembled multilayers >5 nm thick are well described by a single two-parameter Weibull distribution, with β ≈ 11. Multilayers ≤5 nm thick exhibit kinks on the Weibull plot of dielectric breakdown voltage, suggesting that multiple characteristic mechanisms for dielectric breakdown are present. Both the degree of uniformity and the effective dielectric breakdown field are observed to be greater for one layer than for two layers of Zr-SAND, suggesting that this multilayer is more promising for device applications.

  14. Laser-induced breakdown spectroscopy for on-line control of selective removal of cobalt binder from tungsten carbide hardmetal by pulsed UV laser surface ablation

    Science.gov (United States)

    Li, Tiejun; Lou, Qihong; Wei, Yunrong; Huang, Feng; Dong, Jingxing; Liu, Jingru

    2001-09-01

    Laser-induced breakdown spectroscopy (LIBS) was successfully used in on-line control of selective removal of cobalt from tungsten carbide hardmetal by pulsed UV laser surface ablation. The dependence of LIBS on number of laser shots was investigated at different laser fluences. The optimal laser fluence of 2.5 J/cm 2 suited for selective removal of cobalt from surface layer of hardmetal was confirmed. The result sample was also subject to different post-examinations to evaluate the feasibility of the application of LIBS in this laser ablation process. It was demonstrated that, monitoring of the emission intensity of cobalt lines could be used as a control parameter for selective removal of cobalt from surface layer of hardmetal by pulsed UV laser. The on-line implementation of the spectroscopic technique LIBS to the surface-ablation process provided important information about the optimal-ablation parameters.

  15. Qualitative tissue differentiation by analysing the intensity ratios of atomic emission lines using laser induced breakdown spectroscopy (LIBS): prospects for a feedback mechanism for surgical laser systems.

    Science.gov (United States)

    Kanawade, Rajesh; Mahari, Fanuel; Klämpfl, Florian; Rohde, Maximilian; Knipfer, Christian; Tangermann-Gerk, Katja; Adler, Werner; Schmidt, Michael; Stelzle, Florian

    2015-01-01

    The research work presented in this paper focuses on qualitative tissue differentiation by monitoring the intensity ratios of atomic emissions using 'Laser Induced Breakdown Spectroscopy' (LIBS) on the plasma plume created during laser tissue ablation. The background of this study is to establish a real time feedback control mechanism for clinical laser surgery systems during the laser ablation process. Ex-vivo domestic pig tissue samples (muscle, fat, nerve and skin) were used in this experiment. Atomic emission intensity ratios were analyzed to find a characteristic spectral line for each tissue. The results showed characteristic elemental emission intensity ratios for the respective tissues. The spectral lines and intensity ratios of these specific elements varied among the different tissue types. The main goal of this study is to qualitatively and precisely identify different tissue types for tissue specific laser surgery.

  16. Investigation by laser induced breakdown spectroscopy, X-ray fluorescence and X-ray powder diffraction of the chemical composition of white clay ceramic tiles from Veliki Preslav

    Science.gov (United States)

    Blagoev, K.; Grozeva, M.; Malcheva, G.; Neykova, S.

    2013-01-01

    The paper presents the results of the application of laser induced breakdown spectroscopy, X-ray fluorescence spectrometry, and X-ray powder diffraction in assessing the chemical and phase composition of white clay decorative ceramic tiles from the medieval archaeological site of Veliki Preslav, a Bulgarian capital in the period 893-972 AC, well-known for its original ceramic production. Numerous white clay ceramic tiles with highly varied decoration, produced for wall decoration of city's churches and palaces, were found during the archaeological excavations in the old capital. The examination of fourteen ceramic tiles discovered in one of the city's monasteries is aimed at characterization of the chemical profile of the white-clay decorative ceramics produced in Veliki Preslav. Combining different methods and comparing the obtained results provides complementary information regarding the white-clay ceramic production in Veliki Preslav and complete chemical characterization of the examined artefacts.

  17. Development of a deep-sea laser-induced breakdown spectrometer for in situ multi-element chemical analysis

    Science.gov (United States)

    Thornton, Blair; Takahashi, Tomoko; Sato, Takumi; Sakka, Tetsuo; Tamura, Ayaka; Matsumoto, Ayumu; Nozaki, Tatsuo; Ohki, Toshihiko; Ohki, Koichi

    2015-01-01

    Spectroscopy is emerging as a technique that can expand the envelope of modern oceanographic sensors. The selectivity of spectroscopic techniques enables a single instrument to measure multiple components of the marine environment and can form the basis for versatile tools to perform in situ geochemical analysis. We have developed a deep-sea laser-induced breakdown spectrometer (ChemiCam) and successfully deployed the instrument from a remotely operated vehicle (ROV) to perform in situ multi-element analysis of both seawater and mineral deposits at depths of over 1000 m. The instrument consists of a long-nanosecond duration pulse-laser, a spectrometer and a high-speed camera. Power supply, instrument control and signal telemetry are provided through a ROV tether. The instrument has two modes of operation. In the first mode, the laser is focused directly into seawater and spectroscopic measurements of seawater composition are performed. In the second mode, a fiber-optic cable assembly is used to make spectroscopic measurements of mineral deposits. In this mode the laser is fired through a 4 m long fiber-optic cable and is focused onto the target's surface using an optical head and a linear stage that can be held by a ROV manipulator. In this paper, we describe the instrument and the methods developed to process its measurements. Exemplary measurements of both seawater and mineral deposits made during deployments of the device at an active hydrothermal vent field in the Okinawa trough are presented. Through integration with platforms such as underwater vehicles, drilling systems and subsea observatories, it is hoped that this technology can contribute to more efficient scientific surveys of the deep-sea environment.

  18. A model based DC analysis of SiPM breakdown voltages

    CERN Document Server

    Nagy, Ferenc; Kalinka, Gabor; Molnar, Jozsef

    2016-01-01

    A new method to determine the breakdown voltage of SiPMs is presented. It is backed up by a DC model which describes the breakdown phenomenon by distinct avalanche turn-on ($V_{01}$) and turn off ($V_{10}$) voltages. It is shown that $V_{01}$ is related to the 'breakdown voltage' that previous DC methods derive from simple reverse current-voltage measurements, while $V_{10}$ is the 'real' breakdown voltage commonly obtained from complex gain-voltage measurements. The proposed method reveals how the microcell population distributes around $V_{01}$ and $V_{10}$. It is found that if this distribution is assumed to be normal, then both voltages and even their standard deviation can readily be extracted from current-voltage curves. Measurements are in good agreement with the theoretical model.

  19. Evaluation of the standard normal variate method for Laser-Induced Breakdown Spectroscopy data treatment applied to the discrimination of painting layers

    Science.gov (United States)

    Syvilay, D.; Wilkie-Chancellier, N.; Trichereau, B.; Texier, A.; Martinez, L.; Serfaty, S.; Detalle, V.

    2015-12-01

    Nowadays, Laser-Induced Breakdown Spectroscopy (LIBS) is frequently used for in situ analyses to identify pigments from mural paintings. Nonetheless, in situ analyses require a robust instrumentation in order to face to hard experimental conditions. This may imply variation of fluencies and thus inducing variation of LIBS signal, which degrades spectra and then results. Usually, to overcome these experimental errors, LIBS signal is processed. Signal processing methods most commonly used are the baseline subtraction and the normalization by using a spectral line. However, the latter suggests that this chosen element is a constant component of the material, which may not be the case in paint layers organized in stratigraphic layers. For this reason, it is sometimes difficult to apply this normalization. In this study, another normalization will be carried out to throw off these signal variations. Standard normal variate (SNV) is a normalization designed for these conditions. It is sometimes implemented in Diffuse Reflectance Infrared Fourier Transform Spectroscopy and in Raman Spectroscopy but rarely in LIBS. The SNV transformation is not newly applied on LIBS data, but for the first time the effect of SNV on LIBS spectra was evaluated in details (energy of laser, shot by shot, quantification). The aim of this paper is the quick visualization of the different layers of a stratigraphic painting sample by simple data representations (3D or 2D) after SNV normalization. In this investigation, we showed the potential power of SNV transformation to overcome undesired LIBS signal variations but also its limit of application. This method appears as a promising way to normalize LIBS data, which may be interesting for in-situ depth analyses.

  20. Laser-Induced Breakdown Spectroscopy and Its Applications on Element Detections of Agriculture Products%激光诱导击穿光谱技术在农产品检测中的应用

    Institute of Scientific and Technical Information of China (English)

    于巧玲; 谭文波; 石少明; 覃俊达

    2015-01-01

    激光诱导击穿光谱(LIBS)技术是一种利用原子发射光谱定性、定量测定物质组成元素的分析技术。随着激光技术、光谱技术以及相关领域的仪器的发展,激光诱导击穿光谱技术已经成为光谱学领域的研究热点。文章介绍了激光诱导击穿光谱发展、装置和原理,分析了该项技术在农产品检测方面的应用。%Laser-Induced Breakdown Spectroscopy (LIBS) is a convenient and sensitive analysis approach based on atomic emission spectroscopy for the qualitative and quantitative detection of elements. The LIBS has become a hot topic in the spectrometric research field with the development of laser technique, spectrum technique and related instruments. This paper reviewed the history, mechanism and experimental setup of LIBS, and its recent applications on agriculture products detections.

  1. Photoacoustic spectroscopy for process analysis.

    Science.gov (United States)

    Schmid, Thomas

    2006-03-01

    Photoacoustic spectroscopy (PAS) is based on the absorption of electromagnetic radiation by analyte molecules. The absorbed energy is measured by detecting pressure fluctuations in the form of sound waves or shock pulses. In contrast to conventional absorption spectroscopy (such as UV/Vis spectroscopy), PAS allows the determination of absorption coefficients over several orders of magnitude, even in opaque and strongly scattering samples. Small absorption coefficients, such as those encountered during trace gas monitoring, can be detected with cells with relatively short pathlengths. Furthermore, PA techniques allow absorption spectra of solid samples (including powders, chips or large objects) to be determined, and they permit depth profiling of layered systems. These features mean that PAS can be used for on-line monitoring in technical processes without the need for sample preparation and to perform depth-resolved characterization of industrial products. This article gives an overview on PA excitation and detection schemes employed in analytical chemistry, and reviews applications of PAS in process analytical technology and characterization of industrial products.

  2. Detection and Analytical Capabilities for Trace Level of Carbon in High-Purity Metals by Laser-Induced Breakdown Spectroscopy with a Frequency Quintupled 213 nm Nd:YAG Laser

    Directory of Open Access Journals (Sweden)

    Masaki Ohata

    2017-01-01

    Full Text Available The laser-induced breakdown spectroscopy (LIBS with a frequency quintupled 213 nm Nd:YAG laser was examined to the analysis of trace level of carbon (C in high-purity metals and its detection and analytical capabilities were evaluated. Though C signal in a wavelength of 247.9 nm, which showed the highest sensitivity of C, could be obtained from Cd, Ti, and Zn ca. 7000 mg kg−1 C in Fe could not be detected due to the interferences from a lot of Fe spectra. Alternative C signal in a wavelength of 193.1 nm could not be also detected from Fe due to the insufficient laser output energy of the frequency quintupled 213 nm Nd:YAG laser. The depth analysis of C by LIBS was also demonstrated and the C in Cd and Zn was found to be contaminated in only surface area whereas the C in Ti was distributed in bulk. From these results, the frequency quintupled 213 nm Nd:YAG laser, which was adopted widely as a commercial laser ablation (LA system coupled with inductively coupled plasma mass spectrometry (ICPMS for trace element analysis in solid materials, could be used for C analysis to achieve simultaneous measurements for both C and trace elements in metals by LIBS and LA-ICPMS, respectively.

  3. Combined raman/laser-induced breakdown spectrometer: space and non-space applications

    NARCIS (Netherlands)

    Sandtke, M.; Laan, E.C.; Ahlers, B.

    2010-01-01

    TNO has developed the combination of two spectroscopic analysis methods in one instrument. Raman spectroscopy and Laser-induced Breakdown Spectroscopy (LIBS) were brought together for an instrument to be flown on the ExoMars mission from the European Space Agency (ESA) to investigate the Martian (su

  4. Ultrafast pre-breakdown dynamics in Al₂O₃SiO₂ reflector by femtosecond UV laser spectroscopy.

    Science.gov (United States)

    Du, Juan; Li, Zehan; Xue, Bing; Kobayashi, Takayoshi; Han, Dongjia; Zhao, Yuanan; Leng, Yuxin

    2015-06-29

    Ultrafast carrier dynamics in Al2O3/SiO2 high reflectors has been investigated by UV femtosecond laser. It is identified by laser spectroscopy that, the carrier dynamics contributed from the front few layers of Al2O3 play a dominating role in the initial laser-induced damage of the UV reflector. Time-resolved reflection decrease after the UV excitation is observed, and conduction electrons is found to relaxed to a mid-gap defect state locating about one photon below the conduction band . To interpret the laser induced carrier dynamics further, a theoretical model including electrons relaxation to a mid-gap state is built, and agrees very well with the experimental results.. To the best of our knowledge, this is the first study on the pre-damage dynamics in UV high reflector induced by femtosecond UV laser.

  5. The impact of heating the breakdown bubble on the global mode of a swirling jet: Experiments and linear stability analysis

    CERN Document Server

    Rukes, Lothar; Paschereit, Oliver; Oberleithner, Kilian

    2016-01-01

    This study investigates the dynamics of non-isothermal swirling jets undergoing vortex breakdown, with an emphasis on helical coherent structures. It is proposed that the dominant helical coherent structure can be suppressed by heating the recirculation bubble. This proposition is assessed with Stereo Particle Image Velocimetry (PIV) measurements of the breakdown region of isothermal and heated swirling jets. The coherent kinetic energy of the dominant helical structure was derived from PIV snapshots via Proper Orthogonal Decomposition. For one set of experimental parameters, mild heating is found to increase the energy content of the dominant helical mode. Strong heating leads to a reduction by 30\\% of the coherent structures energy. For a second set of experimental parameters, no alteration of the dominant coherent structure is detectable. Local linear stability analysis of the time-averaged velocity fields shows that the key difference between the two configurations is the density ratio at the respective w...

  6. Use of ns and fs pulse excitation in laser-induced breakdown spectroscopy to improve its analytical performances: A case study on quaternary bronze alloys

    Energy Technology Data Exchange (ETDEWEB)

    Almaviva, Salvatore [ENEA, UTAPRAD, V. E. Fermi 45, 00044 Frascati (Italy); Fantoni, Roberta, E-mail: roberta.fantoni@enea.it [ENEA, UTAPRAD, V. E. Fermi 45, 00044 Frascati (Italy); Caneve, Luisa; Colao, Francesco [ENEA, UTAPRAD, V. E. Fermi 45, 00044 Frascati (Italy); Fornarini, Lucilla [ENEA,UTTAMB, SP Anguillarese 301, Roma (Italy); Santagata, Antonio [CNR-IMIP, UOS Potenza, Zona Industriale, 85050 Tito Scalo (PZ) (Italy); Teghil, Roberto [Università degli Studi della Basilicata, Dipartimento di Scienze, Via dell' Ateneo Lucano 10, 85100 Potenza (Italy)

    2014-09-01

    Analytical performances of Laser Induced Breakdown Spectroscopy (LIBS) resulted not fully satisfactory in some cases such as historical bronzes, therefore, efforts should be focussed on improving ablation efficiency and on better understanding the plasma parameter evolution. To this aim a set of double pulse experiments have been carried out in almost collinear geometry at about 530 nm laser excitation. The first emitting source was either a ns or a fs laser the second a ns one. Data were collected as a function of the interpulse delay, in order to determine the ablation efficiency increase, to study the kinetics of plasma parameters (temperature, electron density) and the decay of atomic and ionic intensities with respect to the optical background. In parallel a previously developed model for laser ablation, ionization and following plasma decay, was implemented, adding a second laser pulse, to analyse the double pulse excitation in the considered geometry, and the time evolution of the same variables was investigated. Model results are able to reproduce the observed experimental trends and support the possibility of improving analytical performances by using the double pulse technique with inter-pulse delays in the entire investigated range. - Highlights: • The Double Pulse LIBS technique is applied to a quaternary metal alloy sample. • Two different Double Pulse LIBS configurations are investigated. • Signal enhancement was experimentally verified in the Double Pulse technique. • Comparison of the experimental results with the proposed theoretical model • Dependence of the LIBS signal by some experimental parameters.

  7. Double-pulse laser induced breakdown spectroscopy with ambient gas in the vacuum ultraviolet: Optimization of parameters for detection of carbon and sulfur in steel

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, X., E-mail: xi.jiang2@mail.dcu.ie [School of Physical Sciences, Dublin City University, Dublin (Ireland); National Centre for Plasma Science and Technology, Dublin City University, Dublin (Ireland); Hayden, P. [School of Physics, Atomic, Molecular and Plasma Spectroscopy Group, University College Dublin, Dublin (Ireland); Costello, J.T.; Kennedy, E.T. [School of Physical Sciences, Dublin City University, Dublin (Ireland); National Centre for Plasma Science and Technology, Dublin City University, Dublin (Ireland)

    2014-11-01

    Laser induced breakdown spectroscopy (LIBS) in the vacuum ultraviolet (VUV) has been applied to calibrated steel samples for the low concentration level detection of the light elements, carbon and sulfur in steel. Experimental optimization parameters, aimed at enhancing the sensitivity of the technique, included short wavelength spectral detection, double-pulse (DP) operation, variable focusing conditions and different ambient environments in terms of gas type and pressure. Two lasers were employed respectively as an ablation laser (Spectron: 1.06 μm/200 mJ/15 ns) and a reheating laser (Surelite: 1.06 μm/665 mJ/6 ns) in a collinear geometry. The results include insight into the most salient experimental variables and limits of detection in the parts per million range. - Highlights: • First overall optimization of TISR-LIBS in the deep VUV • First combination of double pulse VUV emission with low pressure ambient gas • The influence of each parameter on the plasm emission • Improvement of LOD for C and S in steel with optimized parameters.

  8. Investigation of Laser Induced Breakdown Spectroscopy (LIBS) for the Differentiation of Nerve and Gland Tissue—A Possible Application for a Laser Surgery Feedback Control Mechanism

    Science.gov (United States)

    Mehari, F.; Rohde, M.; Knipfer, C.; Kanawade, R.; Klämpfl, F.; W., Adler; Oetter, N.; Stelzle, F.; Schmidt, M.

    2016-06-01

    Laser surgery provides clean, fast and accurate modeling of tissue. However, the inability to determine what kind of tissue is being ablated at the bottom of the cut may lead to the iatrogenic damage of structures that were meant to be preserved. In this context, nerve preservation is one of the key challenges in any surgical procedure. One example is the treatment of parotid gland pathologies, where the facial nerve (N. VII) and its main branches run through and fan out inside the glands parenchyma. A feedback system that automatically stops the ablation to prevent nerve-tissue damage could greatly increase the applicability and safety of surgical laser systems. In the present study, Laser Induced Breakdown Spectroscopy (LIBS) is used to differentiate between nerve and gland tissue of an ex-vivo pig animal model. The LIBS results obtained in this preliminary experiment suggest that the measured spectra, containing atomic and molecular emissions, can be used to differentiate between the two tissue types. The measurements and differentiation were performed in open air and under normal stray light conditions.

  9. Study of the feasibility of applying laser-induced breakdown spectroscopy for in-situ characterization of deposited layers in fusion devices

    Science.gov (United States)

    Huber, A.; Schweer, B.; Philipps, V.; Leyte-Gonzales, R.; Gierse, N.; Zlobinski, M.; Brezinsek, S.; Kotov, V.; Mertens, P.; Samm, U.; Sergienko, G.

    2011-12-01

    This paper presents a feasibility study of laser-induced breakdown spectroscopy (LIBS) for the development of an in-situ diagnostic for the characterization of deposition layers on plasma-facing components in fusion devices. Preferentially, LIBS would be applied in the presence of a toroidal magnetic field and under high vacuum conditions. The impact of the laser-energy densities on the laser-induced plasma parameters and correspondingly on the number of emitted photons and on the reproducibility of the LIBS method has been studied in laboratory experiments and in TEXTOR on fine-grain graphite (EK98) as well as on bulk W samples coated with carbon and metallic-containing deposits. The effect of magnetic fields and of ambient pressures in the range from 2×10-4 Pa to 10 Pa on the carbon plasma plume produced by the LIBS technique has been studied on TEXTOR between plasma pulses. The possibility of applying this method to ITER is discussed.

  10. Quantification of fluorine traces in solid samples using CaF molecular emission bands in atmospheric air Laser-Induced Breakdown Spectroscopy

    Science.gov (United States)

    Alvarez-Llamas, C.; Pisonero, J.; Bordel, N.

    2016-09-01

    Direct solid determination of trace amounts of fluorine using Laser-Induced Breakdown Spectroscopy (LIBS) is a challenging task due to the low excitation efficiency of this element. Several strategies have been developed to improve the detection capabilities, including the use of LIBS in a He atmosphere to enhance the signal to background ratios of F atomic emission lines. An alternative method is based on the detection of the molecular compounds that are formed with fluorine in the LIBS plasma. In this work, the detection of CaF molecular emission bands is investigated to improve the analytical capabilities of atmospheric air LIBS for the determination of fluorine traces in solid samples. In particular, Cu matrix samples containing different fluorine concentration (between 50 and 600 μg/g), and variable amounts of Ca, are used to demonstrate the linear relationships between CaF emission signal and F concentration. Limits of detection for fluorine are improved by more than 1 order of magnitude using CaF emission bands versus F atomic lines, in atmospheric-air LIBS. Furthermore, a toothpaste powder sample is used to validate this analytical method. Good agreement is observed between the nominal and the predicted fluorine mass-content.

  11. Investigation by laser induced breakdown spectroscopy, X-ray fluorescence and X-ray powder diffraction of the chemical composition of white clay ceramic tiles from Veliki Preslav

    Energy Technology Data Exchange (ETDEWEB)

    Blagoev, K., E-mail: kblagoev@issp.bas.bg [Institute of Solid State Physics, Bulgarian Academy of Sciences, 72 Tzarigradsko Chaussee, 1784 Sofia (Bulgaria); Grozeva, M., E-mail: margo@issp.bas.bg [Institute of Solid State Physics, Bulgarian Academy of Sciences, 72 Tzarigradsko Chaussee, 1784 Sofia (Bulgaria); Malcheva, G., E-mail: bobcheva@issp.bas.bg [Institute of Solid State Physics, Bulgarian Academy of Sciences, 72 Tzarigradsko Chaussee, 1784 Sofia (Bulgaria); Neykova, S., E-mail: sevdalinaneikova@abv.bg [National Institute of Archaeology with Museum, Bulgarian Academy of Sciences, 2 Saborna, 1000 Sofia (Bulgaria)

    2013-01-01

    The paper presents the results of the application of laser induced breakdown spectroscopy, X-ray fluorescence spectrometry, and X-ray powder diffraction in assessing the chemical and phase composition of white clay decorative ceramic tiles from the medieval archaeological site of Veliki Preslav, a Bulgarian capital in the period 893–972 AC, well-known for its original ceramic production. Numerous white clay ceramic tiles with highly varied decoration, produced for wall decoration of city's churches and palaces, were found during the archaeological excavations in the old capital. The examination of fourteen ceramic tiles discovered in one of the city's monasteries is aimed at characterization of the chemical profile of the white-clay decorative ceramics produced in Veliki Preslav. Combining different methods and comparing the obtained results provides complementary information regarding the white-clay ceramic production in Veliki Preslav and complete chemical characterization of the examined artefacts. - Highlights: ► LIBS, XRF and XRD analyses of medieval white-clay ceramic tiles fragments are done. ► Different elements and phases, presented in the ceramics fragments were determined. ► Differences in the tiles' raw material mineral composition are found. ► Information of the tiles' production process and the raw clay deposits is obtained.

  12. Sensitive determinations of Cu, Pb, Cd, and Cr elements in aqueous solutions using chemical replacement combined with surface-enhanced laser-induced breakdown spectroscopy.

    Science.gov (United States)

    Yang, X Y; Hao, Z Q; Li, C M; Li, J M; Yi, R X; Shen, M; Li, K H; Guo, L B; Li, X Y; Lu, Y F; Zeng, X Y

    2016-06-13

    In this study, chemical replacement combined with surface-enhanced laser-induced breakdown spectroscopy (CR-SENLIBS) was for the first time applied to improve the detection sensitivities of trace heavy metal elements in aqueous solutions. Utilizing chemical replacement effect, heavy metal ions in aqueous solution were enriched on the magnesium alloy surface as a solid replacement layer through reacting with the high chemical activity metallic magnesium (Mg) within 1 minute. Unitary and mixed solutions with Cu, Pb, Cd, and Cr elements were prepared to construct calibration curves, respectively. The CR-SENLIBS showed a much better detection sensitivity and accuracy for both unitary and mixed solutions. The coefficients of determination R2 of the calibration curves were above 0.96, and the LoDs were of the same order of magnitude, i.e., in the range of 0.016-0.386 μg/mL for the unitary solution, and in the range of 0.025-0.420 μg/mL for the mixed solution. These results show that CR-SENLIBS is a feasible method for improving the detection sensitivity of trace element in liquid sample, which definitely provides a way for wider application of LIBS in water quality monitoring.

  13. Improvement of the Laser-Induced Breakdown Spectroscopy method sensitivity by the usage of combination of Ag-nanoparticles and vacuum conditions

    Science.gov (United States)

    Sládková, Lucia; Prochazka, David; Pořízka, Pavel; Škarková, Pavlína; Remešová, Michaela; Hrdlička, Aleš; Novotný, Karel; Čelko, Ladislav; Kaiser, Jozef

    2017-01-01

    In this work we studied the effect of vacuum (low pressure) conditions on the behavior of laser-induced plasma (LIP) created on a sample surface covered with silver nanoparticles (Ag-NPs), i.e. Nanoparticles-Enhanced Laser-Induced Breakdown Spectroscopy (NELIBS) experiment in a vacuum. The focus was put on the step by step optimization of the measurement parameters, such as energy of the laser pulse, temporally resolved detection, ambient pressure, and different content of Ag-NPs applied on the sample surface. The measurement parameters were optimized in order to achieve the greatest enhancement represented as the signal-to-noise ratio (SNR) of NELIBS signal to the SNR of LIBS signal. The presence of NPs involved in the ablation process enhances LIP intensity; hence the improvement in the analytical sensitivity was yielded. A leaded brass standard was analyzed with the emphasis on the signal enhancement of Pb traces. We gained enhancement by a factor of four. Although the low pressure had no significant influence on the LIP signal enhancement compared to that under ambient conditions, the SNR values were noticeably improved with the implementation of the NPs.

  14. Laser induced breakdown spectroscopy for bone and cartilage differentiation - ex vivo study as a prospect for a laser surgery feedback mechanism.

    Science.gov (United States)

    Mehari, Fanuel; Rohde, Maximilian; Knipfer, Christian; Kanawade, Rajesh; Klämpfl, Florian; Adler, Werner; Stelzle, Florian; Schmidt, Michael

    2014-11-01

    Laser surgery enables for very accurate, fast and clean modeling of tissue. The specific and controlled cutting and ablation of tissue, however, remains a central challenge in the field of clinical laser applications. The lack of information on what kind of tissue is being ablated at the bottom of the cut may lead to iatrogenic damage of structures that were meant to be preserved. One such example is the shaping or removal of diseased cartilaginous and bone tissue in the temporomandibular joint (TMJ). Diseases of the TMJ can induce deformation and perforation of the cartilaginous discus articularis, as well as alterations to the cartilaginous surface of the condyle or even the bone itself. This may result in restrictions of movement and pain. The aim of a surgical intervention ranges from specific ablation and shaping of diseased cartilage, bone or synovial tissues to extensive removal of TMJ structures. One approach to differentiate between these tissues is to use Laser Induced Breakdown Spectroscopy (LIBS). The ultimate goal is a LIBS guided feedback control system for surgical laser systems that enables real-time tissue identification for tissue specific ablation. In the presented study, the authors focused on the LIBS based differentiation between cartilage tissue and cortical bone tissue using an ex-vivo pig model.

  15. Characteristics of the calibration curves of copper for the rapid sorting of steel scrap by means of laser-induced breakdown spectroscopy under ambient air atmospheres.

    Science.gov (United States)

    Kashiwakura, Shunsuke; Wagatsuma, Kazuaki

    2013-01-01

    For the rapid and precise sorting of steel scrap with relatively high contents of copper, laser-induced breakdown spectroscopy (LIBS) is a promising method. It has several advantages such that it can work under ambient air atmospheres, and specimens can be tested without any pretreatment, such as acid digestion, polishing of the surface of the specimens, etc. For the application of LIBS for actual steel scrap, we obtained emission spectra by an LIBS system, which was mainly comprised of an Nd:YAG laser, an Echelle-type spectrometer, and an ICCD detector. The standard reference materials (SRMs) of JISF FXS 350-352, which are Fe-Cu binary alloy and have certified concentrations of copper, were employed for making calibration lines. Considering spectral interferences from the emission lines of the iron matrix in the alloys, Cu I lines having wavelengths of 324.754 and 327.396 nm could be chosen. In five replicate measurements of each SRM, shorter delay times after laser irradiation and longer gate widths for detecting the transient emission signal are suggested to be the optimal experiment parameters. In the determination process, utilizing the calibration line from Cu I 327.396 nm was better because of less spectral interference. By using 200 pulsed laser shots for the measurement sequence, a limit of detection of 0.004 Cu at% could be obtained.

  16. Issues in deep ocean collinear double-pulse laser induced breakdown spectroscopy: Dependence of emission intensity and inter-pulse delay on solution pressure

    Energy Technology Data Exchange (ETDEWEB)

    Lawrence-Snyder, Marion; Scaffidi, Jonathan P.; Pearman, William F.; Gordon, Christopher M.; Angel, S. Michael

    2014-09-01

    Double-pulse laser-induced breakdown spectroscopy (DP-LIBS) with a collinear laser beam orientation is shown for high-pressure bulk aqueous solutions (up to 50 bar) along with bubble and plasma images. These investigations reveal that the emission plasma is quenched much more rapidly in solution requiring much shorter detector gate delays than for typical LIBS measurements in air. Also, the emission is inversely proportional to solution pressure, and the most intense emission at all pressures occurs when the laser-induced vapor bubble is at a maximum diameter. It is also shown that the laser-induced bubble grows initially at the same rate for all solution pressures, collapsing more quickly as the pressure is increased. Intense emission is best obtained for conditions where the laser-induced bubble formed by the first laser pulse is small and spherically shaped. - Highlights: • Collinear double-pulse LIBS is shown for 50 bar bulk aqueous solutions. • LIBS plasma in solution is much more rapidly quenched than a LIBS plasma in air. • For DP LIBS, the emission is inversely proportional to solution pressure. • Laser-induced bubble growth rate is the same at all solution pressures. • Large spherical laser-induced bubbles produce the strongest DP LIBS emission.

  17. Rapid long-wave infrared laser-induced breakdown spectroscopy measurements using a mercury-cadmium-telluride linear array detection system.

    Science.gov (United States)

    Yang, Clayton S-C; Brown, Eiei; Kumi-Barimah, Eric; Hommerich, Uwe; Jin, Feng; Jia, Yingqing; Trivedi, Sudhir; D'souza, Arvind I; Decuir, Eric A; Wijewarnasuriya, Priyalal S; Samuels, Alan C

    2015-11-20

    In this work, we develop a mercury-cadmium-telluride linear array detection system that is capable of rapidly capturing (∼1-5  s) a broad spectrum of atomic and molecular laser-induced breakdown spectroscopy (LIBS) emissions in the long-wave infrared (LWIR) region (∼5.6-10  μm). Similar to the conventional UV-Vis LIBS, a broadband emission spectrum of condensed phase samples covering the whole 5.6-10 μm region can be acquired from just a single laser-induced microplasma or averaging a few single laser-induced microplasmas. Atomic and molecular signature emission spectra of solid inorganic and organic tablets and thin liquid films deposited on a rough asphalt surface are observed. This setup is capable of rapidly probing samples "as is" without the need of elaborate sample preparation and also offers the possibility of a simultaneous UV-Vis and LWIR LIBS measurement.

  18. Three-dimensional vortex analysis and aeroacoustic source characterization of jet core breakdown

    NARCIS (Netherlands)

    Violato, D.; Scarano, F.

    2013-01-01

    The three-dimensional behavior of jet core breakdown is investigated with experiments conducted on a free water jet at Re = 5000 by time-resolved tomographic particle image velocimetry (TR-TOMO PIV). The investigated domain encompasses the range between 0 and 10 jet diameters. The characteristic pul

  19. Quantification of fluorite mass-content in powdered ores using a Laser-Induced Breakdown Spectroscopy method based on the detection of minor elements and CaF molecular bands

    Energy Technology Data Exchange (ETDEWEB)

    Álvarez, C.; Pisonero, J., E-mail: pisonerojorge@uniovi.es; Bordel, N., E-mail: bordel@uniovi.es

    2014-10-01

    Laser Induced Breakdown Spectroscopy (LIBS) is investigated as a fast and robust method to determine the fluorite (CaF{sub 2}) mass-content of powdered ore samples. Calibrating samples covering a wide CaF{sub 2} concentration range (from 2.3 to 97.6%) are employed. LIBS operating conditions are optimized for the analysis of elemental emission lines and molecular bands, respectively. In particular, LIBS emission intensities from different CaF molecular bands are evaluated to calibrate the fluorite concentration as an alternative to the use of atomic fluorine F I emission lines. Furthermore, the determination of LIBS emission signals from minor elements (e.g. Si I and Mg I) is studied to further improve the accuracy and precision of pure fluorite sample analyses (e.g. [CaF{sub 2}] > 75%). The proposed LIBS method avoids the tedious dissolution processes that are required by other analytical methods employed in mining industry for the quantitative analysis of fluorite. - Highlights: • Fluorite ore mass-content is determined using a LIBS system. • F I emission line at 685.60 nm is used to calibrate the fluorite mass-content. • CaF emission bands are used to quantify samples with low CaF2 concentrations. • Minor elements are used to quantify samples with high CaF2 concentrations.

  20. CFD simulations of a wind turbine for analysis of tip vortex breakdown

    Science.gov (United States)

    Kimura, K.; Tanabe, Y.; Aoyama, T.; Matsuo, Y.; Arakawa, C.; Iida, M.

    2016-09-01

    This paper discusses about the wake structure of wind turbine via the use of URANS and Quasi-DNS, focussing on the tip vortex breakdown. The moving overlapped structured grids CFD Solver based on a fourth-order reconstruction and an all-speed scheme, rFlow3D is used for capturing the characteristics of tip vortices. The results from the Model Experiments in Controlled Conditions project (MEXICO) was accordingly selected for executing wake simulations through the variation of tip speed ratio (TSR); in an operational wind turbine, TSR often changes in value. Therefore, it is important to assess the potential effects of TSR on wake characteristics. The results obtained by changing TSR show the variations of the position of wake breakdown and wake expansion. The correspondence between vortices and radial/rotational flow is also confirmed.

  1. Applying the Different Statistical Tests in Analysis of Electrical Breakdown Mechanisms in Nitrogen Filled Gas Diode

    Science.gov (United States)

    Čedomir, A. Maluckov; Saša, A. Rančev; Miodrag, K. Radović

    2016-10-01

    This paper presents the results of our investigations of breakdown mechanisms, as well as a description of their influence on the distributions of time delay distributions, for a gas tube filled with nitrogen at 4 mbar. The values of the time delay are measured for different voltages, and the values of the relaxation times and their distributions and probability plots are analyzed. The obtained density distributions have Gaussian distributions and exponential distributions for different values of relaxation times (Gaussian for small values and exponential for large values of relaxation time). It is shown that for middle values of relaxation time the delay distributions have a shape between Gaussian and exponential distributions, which is a result of the different influences of electrical breakdown.

  2. Coal gasification systems engineering and analysis. Appendix H: Work breakdown structure

    Science.gov (United States)

    1980-01-01

    A work breakdown structure (WBS) is presented which encompasses the multiple facets (hardware, software, services, and other tasks) of the coal gasification program. The WBS is shown to provide the basis for the following: management and control; cost estimating; budgeting and reporting; scheduling activities; organizational structuring; specification tree generation; weight allocation and control; procurement and contracting activities; and serves as a tool for program evaluation.

  3. Analysis of breakdown on thermal and electrical measurements for SPIDER accelerating grids

    Energy Technology Data Exchange (ETDEWEB)

    Pesce, Alberto, E-mail: alberto.pesce@igi.cnr.it [Consorzio RFX - Associazione EURATOM-ENEA per la fusione, Corso Stati Uniti 4, 35127 Padova (Italy); Pomaro, Nicola [Consorzio RFX - Associazione EURATOM-ENEA per la fusione, Corso Stati Uniti 4, 35127 Padova (Italy)

    2011-10-15

    The PRIMA test facility, under realization in Padova, includes a full size plasma source prototype for ITER, called SPIDER (Source for the Production of Ions of Deuterium Extracted from Radio Frequency plasma). The effects of breakdown in the electrical insulation inside the ion source are analyzed with particular care to the embedded diagnostic system, i.e. the thermal and electrical measurements installed on the grids and ion source case and transferred by multipolar cables to the acquisition system, located inside the 100 kV insulated deck and hosting the ion source power supply, the signal conditioning and the acquisition cubicles. The breakdown affects strongly the measurements, so it has to be mitigated in order to guarantee adequate reliability of the whole measurement set. A parametric study has been carried out on a detailed circuital model for fast transients, implemented using SimPowerSystems{sup TM} tool of Matlab Simulink code. The model includes all the relevant conductors of the subsystems downstream the insulating transformer of the Accelerating Grids Power Supply (AGPS), i.e. the AGPS rectifier, the multipolar transmission line, the 100 kV High Voltage Deck, the ion source power supply and the ion source itself. In particular all the magnetic and capacitive couplings have been computed by a proper 2D fem model. The optimization of the cabling layout, of the wire screening and of the protection devices, like surge arresters and resistors, has been carried out through the accurate modeling of the circuit. The energy dissipated on each ion source surge arrester is estimated and adequate TSD (transient suppression devices) are selected. A peculiar and difficult to satisfy requirement is the high number of surges that the TSD has to withstand. Breakdowns between components polarized at different voltages have been considered, in order to inspect the worst condition during a breakdown.

  4. Mapping of rare earth elements in nuclear waste glass–ceramic using micro laser-induced breakdown spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Wang, X.; Motto-Ros, V. [ILM, UMR5306, Université Lyon 1 — CNRS, Université de Lyon, F-69622, Lyon (France); Panczer, G., E-mail: gerard.panczer@univ-lyon1.fr [ILM, UMR5306, Université Lyon 1 — CNRS, Université de Lyon, F-69622, Lyon (France); De Ligny, D.; Yu, J.; Benoit, J.M. [ILM, UMR5306, Université Lyon 1 — CNRS, Université de Lyon, F-69622, Lyon (France); Dussossoy, J.L.; Peuget, S. [CEA, DEN, DTCD/SECM/LMPA-Marcoule, F-30207 Bagnols-sur-Cèze (France)

    2013-09-01

    A micro-LIBS system was set up based on a quadruple Nd:YAG laser at 266 nm coupled with a microscope. Elemental mapping was performed on a Mo-rich glass–ceramic sample containing CaMoO{sub 4} crystallites hundreds of microns in length and about 25 μm in section diameter. The topography of single-shot laser-induced craters was characterized using an atomic force microscope (AFM), which revealed a crater size less than 7 μm. Mappings of Mo, Ca, Sr, Al, Fe, Zr and rare earth elements such as Eu, Nd, Pr and La were undertaken. Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) was conducted to validate the micro-LIBS analysis. Principal components analysis calculation was used to investigate the correlation of elements in the two phases of glass–ceramic. Correlation between Ca, Sr, rare earth elements and Mo indicates their preferential incorporation into the calcium molybdate crystalline phase. Anti-correlation between Fe, Zr, Al and Mo revealed their affinity to the glass phase. - Highlights: • A dedicated micro-LIBS system was set up to perform fast elemental mapping. • Mapping was conducted on a Mo-rich nuclear waste glass–ceramic for the first time. • Mo, Ca, Sr, Eu, Nd, La, Pr, Al, Fe and Zr were detected in one spectral range. • Crater size was about 5 μm on crystallites of the sample. • Fractionation behavior of elements was investigated by principal components analysis.

  5. Time-resolved measurement of atomic emission enhancement by fs-ns dual-pulsed laser-induced breakdown spectroscopy

    Institute of Scientific and Technical Information of China (English)

    Yan Li-Xin; Zhang Yong-Sheng; Zheng Guo-Xin; Liu Jing-Ru; Cheng Jian-Ping; Lü Min

    2006-01-01

    Time-resolved measurement of atomic emission enhancement is performed by using a 500-fs KrF laser pulse incident upon a high density supersonic O2 gas jet, synchronized with an orthogonal ns frequency-doubled Nd:YAG laser pulse. The ultra-short pulse serves as an igniter of the gas jet, and the subsequent ns-laser pulse significantly enhances the atomic emission. Analysis shows that the contributions to the enhancement effect are made mainly by the bremsstrahlung radiation and cascade ionization.

  6. Modeling of low-temperature plasmas generated using laser-induced breakdown spectroscopy: the ChemCam diagnostic tool on the Mars Science Laboratory Rover

    Science.gov (United States)

    Colgan, James

    2016-05-01

    We report on efforts to model the low-temperature plasmas generated using laser-induced breakdown spectroscopy (LIBS). LIBS is a minimally invasive technique that can quickly and efficiently determine the elemental composition of a target and is employed in an extremely wide range of applications due to its ease of use and fast turnaround. In particular, LIBS is the diagnostic tool used by the ChemCam instrument on the Mars Science Laboratory rover Curiosity. In this talk, we report on the use of the Los Alamos plasma modeling code ATOMIC to simulate LIBS plasmas, which are typically at temperatures of order 1 eV and electron densities of order 10 16 - 17 cm-3. At such conditions, these plasmas are usually in local-thermodynamic equilibrium (LTE) and normally contain neutral and singly ionized species only, which then requires that modeling must use accurate atomic structure data for the element under investigation. Since LIBS devices are often employed in a very wide range of applications, it is therefore desirable to have accurate data for most of the elements in the periodic table, ideally including actinides. Here, we discuss some recent applications of our modeling using ATOMIC that have explored the plasma physics aspects of LIBS generated plasmas, and in particular discuss the modeling of a plasma formed from a basalt sample used as a ChemCam standard1. We also highlight some of the more general atomic physics challenges that are encountered when attempting to model low-temperature plasmas. The Los Alamos National Laboratory is operated by Los Alamos National Security, LLC for the National Nuclear Security Administration of the U.S. Department of Energy under Contract No. DE-AC5206NA25396. Work performed in conjunction with D. P. Kilcrease, H. M. Johns, E. J. Judge, J. E. Barefield, R. C. Wiens, S. M. Clegg.

  7. On the determination of plasma electron number density from Stark broadened hydrogen Balmer series lines in Laser-Induced Breakdown Spectroscopy experiments

    Energy Technology Data Exchange (ETDEWEB)

    Pardini, L., E-mail: loren.pard@gmail.com [Istituto di Chimica dei Composti Organometallici del CNR, Area della Ricerca del CNR di Pisa, Via G. Moruzzi 1, 56124 Pisa (Italy); Legnaioli, S.; Lorenzetti, G.; Palleschi, V. [Istituto di Chimica dei Composti Organometallici del CNR, Area della Ricerca del CNR di Pisa, Via G. Moruzzi 1, 56124 Pisa (Italy); Gaudiuso, R.; De Giacomo, A. [Dipartimento di Chimica, Università di Bari, Via Orabona 4, 70126 Bari (Italy); Diaz Pace, D.M. [Instituto de Física ‘Arroyo Seco’, Facultad de Ciencias Exactas, Paraje Arroyo Seco, B7000GHG Tandil (Argentina); Anabitarte Garcia, F. [Photonic Engineering Group, Universidad de Cantabria, Edificio I+D+iTelecomunicación, Dpto. TEISA, 39005 Santander (Spain); Holanda Cavalcanti, G. de [Institute of Physics, Universidade Federal Fluminense, UFF, Campus da Praia Vermelha, Av. Gal Milton Tavares de Souza, Gragoatá, 24310 240 Niterói, RJ (Brazil); Parigger, C. [University of Tennessee Space Institute, 411 B. H. Goethert Parkway, Tullahoma, TN 37388-9700 (United States)

    2013-10-01

    In this work, different theories for the determination of the electron density in Laser-Induced Breakdown Spectroscopy (LIBS) utilizing the emission lines belonging to the hydrogen Balmer series have been investigated. The plasmas were generated by a Nd:Yag laser (1064 nm) pulsed irradiation of pure hydrogen gas at a pressure of 2 · 10{sup 4} Pa. H{sub α}, Η{sub β}, Η{sub γ}, Η{sub δ}, and H{sub ε} Balmer lines were recorded at different delay times after the laser pulse. The plasma electron density was evaluated through the measurement of the Stark broadenings and the experimental results were compared with the predictions of three theories (the Standard Theory as developed by Kepple and Griem, the Advanced Generalized Theory by Oks et al., and the method discussed by Gigosos et al.) that are commonly employed for plasma diagnostics and that describe LIBS plasmas at different levels of approximations. A simple formula for pure hydrogen plasma in thermal equilibrium was also proposed to infer plasma electron density using the H{sub α} line. The results obtained showed that at high hydrogen concentration, the H{sub α} line is affected by considerable self-absorption. In this case, it is preferable to use the H{sub β} line for a reliable calculation of the electron density. - Highlights: • We evaluated the electron density in LIPs utilizing the hydrogen Balmer series. • Plasmas were generated by a Nd:Yag laser (1064 nm) on pure hydrogen gas. • We show that at high hydrogen concentration, H{sub b}eta line is preferable than H{sub a}lpha. • We propose a formula to derive the plasma electron density using the H{sub a}lpha line.

  8. The Enhanced Effect of Optical Emission from Laser Induced Breakdown Spectroscopy of an Al-Li Alloy in the Presence of Magnetic Field Confinement

    Science.gov (United States)

    Liu, Ping; Hai, Ran; Wu, Ding; Xiao, Qingmei; Sun, Liying; Ding, Hongbin

    2015-08-01

    In this paper, the influence of magnetic field strength on laser-induced breakdown spectroscopy (LIBS) has been investigated for various pressures. The plasma plume was produced by employing Q-switch Nd:YAG laser ablation of an Al-Li alloy operating at a 1064 nm wavelength. The results indicated that the LIBS intensity of the Al and Li emission lines is boosted with an increase of magnetic strength. Typically, the intensity of the Al I and Li I spectral emissions can be magnified by 1.5-3 times in a steady magnetic field of 1.1 T compared with the field-free case. Also, in this investigation we recorded time-resolved images of the laser-produced plume by employing a fast ICCD camera. The results show that the luminance of the plasma is enhanced and the time of persistence is increased significantly, and the plasma plume splits into two lobes in the presence of a magnetic field. The probable reason for the enhancement is the magnetic confinement effect which increases the number density of excited atoms and the population of species in a high energy state. In addition, the electron temperature and density are also augmented by the magnetic field compared to the field-free case. supported by the National Magnetic Confinement Fusion Science Program of China (No. 2013GB109005) and National Natural Science Foundation of China (No. 11175035), Chinesisch-Deutsches Forschungs Project (GZ768), the Fundamental Research Funds for the Central Universities, China (Nos. DUT12ZD(G)01, (DUT14ZD(G)04), MMLab Research Project (DP1051208)

  9. Pre-flight calibration and initial data processing for the ChemCam laser-induced breakdown spectroscopy instrument on the Mars Science Laboratory rover

    Science.gov (United States)

    Wiens, R.C.; Maurice, S.; Lasue, J.; Forni, O.; Anderson, R.B.; Clegg, S.; Bender, S.; Blaney, D.; Barraclough, B.L.; Cousin, A.; DeFlores, L.; Delapp, D.; Dyar, M.D.; Fabre, C.; Gasnault, O.; Lanza, N.; Mazoyer, J.; Melikechi, N.; Meslin, P.-Y.; Newsom, H.; Ollila, A.; Perez, R.; Tokar, R.; Vaniman, D.

    2013-01-01

    The ChemCam instrument package on the Mars Science Laboratory rover, Curiosity, is the first planetary science instrument to employ laser-induced breakdown spectroscopy (LIBS) to determine the compositions of geological samples on another planet. Pre-processing of the spectra involves subtracting the ambient light background, removing noise, removing the electron continuum, calibrating for the wavelength, correcting for the variable distance to the target, and applying a wavelength-dependent correction for the instrument response. Further processing of the data uses multivariate and univariate comparisons with a LIBS spectral library developed prior to launch as well as comparisons with several on-board standards post-landing. The level-2 data products include semi-quantitative abundances derived from partial least squares regression. A LIBS spectral library was developed using 69 rock standards in the form of pressed powder disks, glasses, and ceramics to minimize heterogeneity on the scale of the observation (350–550 μm dia.). The standards covered typical compositional ranges of igneous materials and also included sulfates, carbonates, and phyllosilicates. The provenance and elemental and mineralogical compositions of these standards are described. Spectral characteristics of this data set are presented, including the size distribution and integrated irradiances of the plasmas, and a proxy for plasma temperature as a function of distance from the instrument. Two laboratory-based clones of ChemCam reside in Los Alamos and Toulouse for the purpose of adding new spectra to the database as the need arises. Sensitivity to differences in wavelength correlation to spectral channels and spectral resolution has been investigated, indicating that spectral registration needs to be within half a pixel and resolution needs to match within 1.5 to 2.6 pixels. Absolute errors are tabulated for derived compositions of each major element in each standard using PLS regression

  10. Imaging spectroscopy for scene analysis

    CERN Document Server

    Robles-Kelly, Antonio

    2012-01-01

    This book presents a detailed analysis of spectral imaging, describing how it can be used for the purposes of material identification, object recognition and scene understanding. The opportunities and challenges of combining spatial and spectral information are explored in depth, as are a wide range of applications. Features: discusses spectral image acquisition by hyperspectral cameras, and the process of spectral image formation; examines models of surface reflectance, the recovery of photometric invariants, and the estimation of the illuminant power spectrum from spectral imagery; describes

  11. Spectral identifiers from roasting process of Arabica and Robusta green beans using Laser-Induced Breakdown Spectroscopy (LIBS)

    Science.gov (United States)

    Wirani, Ayu Puspa; Nasution, Aulia; Suyanto, Hery

    2016-11-01

    Coffee (Coffea spp.) is one of the most widely consumed beverages in the world. World coffee consumption is around 70% comes from Arabica, 26% from Robusta , and the rest 4% from other varieties. Coffee beverages characteristics are related to chemical compositions of its roasted beans. Usually testing of coffee quality is subjectively tasted by an experienced coffee tester. An objective quantitative technique to analyze the chemical contents of coffee beans using LIBS will be reported in this paper. Optimum experimental conditions was using of 120 mJ of laser energy and delay time 1 μs. Elements contained in coffee beans are Ca, W, Sr, Mg, Na, H, K, O, Rb, and Be. The Calcium (Ca) is the main element in the coffee beans. Roasting process will cause the emission intensity of Ca decreased by 42.45%. In addition, discriminant analysis was used to distinguish the arabica and robusta variants, either in its green and roasted coffee beans. Observed identifier elements are Ca, W, Sr, and Mg. Overall chemical composition of roasted coffee beans are affected by many factors, such as the composition of the soil, the location, the weather in the neighborhood of its plantation, and the post-harvesting process of the green coffee beans (drying, storage, fermentation, and roasting methods used).

  12. Laser-Induced Breakdown Spectroscopy (LIBS) for spectral characterization of regular coffee beans and luwak coffee bean

    Science.gov (United States)

    Nufiqurakhmah, Nufiqurakhmah; Nasution, Aulia; Suyanto, Hery

    2016-11-01

    Luwak (civet) coffee refers to a type of coffee, where the cherries have been priorly digested and then defecated by a civet (Paradoxurus Hermaphroditus), a catlike animals typically habited in Indonesia. Luwak will only selectively select ripe cherries, and digesting them by enzymatic fermentation in its digestive system. The defecated beans is then removed and cleaned from the feces. It is regarded as the world's most expensive coffee, Traditionally the quality of the coffee is subjectively determined by a tester. This research is motivated by the needs to study and develop quantitative parameters in determining the quality of coffee bean, which are more objective to measure the quality of coffee products. LIBS technique was used to identify the elemental contents of coffee beans based on its spectral characteristics in the range 200-900 nm. Samples of green beans from variant of arabica and robusta, either regular and luwak, were collected from 5 plantations in East Java. From the recorded spectra, intensity ratio of nitrogen (N), hydrogen (H), and oxygen (O) as essential elements in coffee is applied. In general, values extracted from luwak coffee bean is higher with increases 0.03% - 79.93%. A Discriminant Function Analysis (DFA) also applied to identify marker elements that characterize the regular and luwak beans. Elements of Ca, W, Sr, Mg, and H are the ones used to differentiate the regular and luwak beans from arabica variant, while Ca and W are the ones used to differentiate the regular and luwak beans of robusta variant.

  13. Fourier Transform Infrared Spectroscopy and Photoacoustic Spectroscopy for Saliva Analysis.

    Science.gov (United States)

    Mikkonen, Jopi J W; Raittila, Jussi; Rieppo, Lassi; Lappalainen, Reijo; Kullaa, Arja M; Myllymaa, Sami

    2016-09-01

    Saliva provides a valuable tool for assessing oral and systemic diseases, but concentrations of salivary components are very small, calling the need for precise analysis methods. In this work, Fourier transform infrared (FT-IR) spectroscopy using transmission and photoacoustic (PA) modes were compared for quantitative analysis of saliva. The performance of these techniques was compared with a calibration series. The linearity of spectrum output was verified by using albumin-thiocyanate (SCN(-)) solution at different SCN(-) concentrations. Saliva samples used as a comparison were obtained from healthy subjects. Saliva droplets of 15 µL were applied on the silicon sample substrate, 6 drops for each specimen, and dried at 37 ℃ overnight. The measurements were carried out using an FT-IR spectrometer in conjunction with an accessory unit for PA measurements. The findings with both transmission and PA modes mirror each other. The major bands presented were 1500-1750 cm(-1) for proteins and 1050-1200 cm(-1) for carbohydrates. In addition, the distinct spectral band at 2050 cm(-1) derives from SCN(-) anions, which is converted by salivary peroxidases to hypothiocyanate (OSCN(-)). The correlation between the spectroscopic data with SCN(-) concentration (r > 0.990 for transmission and r = 0.967 for PA mode) was found to be significant (P < 0.01), thus promising to be utilized in future applications.

  14. Laser Induced Breakdown Spectroscopy (LIBS)

    Science.gov (United States)

    2010-03-31

    depositors favored large denominations causing the smaller denominations to become essentially worthless and obsolete. With the Coinage Act of February...Thallium 201 Hydrogen cyanide (AC) FUNGI Thorium 232 Cyanogen chloride (CK) Aflatoxin Lead 210 Arsine (SA) Bacillus Sodium 22...fuel oil ]. Bromazepam (PIM 281) Aromatic nitro-compound explosive mixtures. Brotizolam (PIM 919) Azide explosives. Bupivacaine (PIM

  15. Application of Infrared Spectroscopy in Honey Analysis

    Directory of Open Access Journals (Sweden)

    Lidija Svečnjak

    2011-10-01

    Full Text Available The chemical composition and sensory characteristics vary significantly within different honey types. In order to determine botanical origin of honey, it is necessary to conduct rather complicated and time consuming analytical methods. IR spectroscopy has not yet been experimentally explored for honey analysis in Croatia, so the aim of this study was to determine claimed botanical origin of honey using both, standard and alternative (IR spectroscopy methods, for the purpose of their comparison, Altogether 144 samples of nine different unifloral honey types (black locust, sweet chestnut, lime, sage, heath, rosemary, lavender, mandarin and strawberry tree were collected from different Croatian regions directly from the beekeepers. In order to confirm claimed botanical origin of collected honey samples, melissopalinological analysis, moisture and electrical conductivity measurements were conducted. Infrared spectra of honey samples were recorded using the ABB Bomem MB102 Fourier-transform infrared spectrometer (FT-IR spectrometer. Selected IR spectral regions were analyzed by multivariate data analysis, principal components analysis (PCA. Preliminary PCA of IR spectra showed significant clustering of the analyzed samples by botanical origin. The results of this study showed that IR spectroscopy provides reliable results, but also represents rapid and cheap analytical tool in comparison to commonly used standard analytical methods. This research has also provided the first insight in infrared spectra of Croatian honeys.

  16. Modeling and analysis of breakdown EMI protection for MITICA insulation and embedded diagnostics

    Energy Technology Data Exchange (ETDEWEB)

    Pesce, A., E-mail: alberto.pesce@igi.cnr.it [Consorzio RFX – Associazione EURATOM-ENEA sulla Fusione, Corso Stati Uniti 4, 35127 Padova (Italy); Pomaro, N.; Zamengo, A.; Bigi, M.; Toigo, V. [Consorzio RFX – Associazione EURATOM-ENEA sulla Fusione, Corso Stati Uniti 4, 35127 Padova (Italy)

    2013-10-15

    Highlights: ► A fast transient model of MITICA electrical system with all relevant conductors has been developed. ► MITICA insulations on Source and main Bushing are at high risk due to electrical breakdowns. ► The introduction of capacitances in some critical points is effective to reduce overvoltages. ► Signal cables must be screened at both ends to and follow the route of reference potential conductors. -- Abstract: On the Padova PRIMA facility the prototype of the ITER HNBs will be tested in the device called MITICA (Megavolt ITER Injector and Concept Advancement). During Beam operation breakdowns will occur across the accelerator grids and Source components causing transient high voltages between parts normally at low voltages, so stressing the electrical insulation of sensor cables, connectors and feedthroughs. The MITICA electrical model implemented to estimate the characteristics of the voltage transients is here described, with particular emphasis on the feedthroughs, on the source insulation and on the embedded diagnostic system. As severe stresses result with the present design mitigating measures are necessary to avoid damage and maintain proper operation. The solution proposed and supported by the analyses to introduce concentrated capacitances in some critical points turns out to be suitable in terms of electrical effects and of technical compatibility with the main requirements of MITICA environment.

  17. Spectroscopy

    DEFF Research Database (Denmark)

    Berg, Rolf W.

    This introductory booklet covers the basics of molecular spectroscopy, infrared and Raman methods, instrumental considerations, symmetry analysis of molecules, group theory and selection rules, as well as assignments of fundamental vibrational modes in molecules.......This introductory booklet covers the basics of molecular spectroscopy, infrared and Raman methods, instrumental considerations, symmetry analysis of molecules, group theory and selection rules, as well as assignments of fundamental vibrational modes in molecules....

  18. Pilot study of laser induced breakdown spectroscopy for tissue differentiation by monitoring the plume created during laser surgery — An approach on a feedback Laser control mechanism

    Energy Technology Data Exchange (ETDEWEB)

    Kanawade, Rajesh, E-mail: Rajesh.Kanawade@aot.uni-erlangen.de [Clinical Photonics Lab, Erlangen Graduate School in Advanced Optical Technologies (SAOT), Friedrich-Alexander-Universität Erlangen-Nürnberg, Paul-Gordan-Str. 6, 91052 Erlangen (Germany); Institute of Photonics Technologies, Friedrich-Alexander-Universität Erlangen-Nürnberg, Paul-Gordan-Str. 3, 91052 Erlangen (Germany); Mehari, Fanuel [Master Programme in Advanced Optical Technologies (MAOT), Friedrich-Alexander-Universität Erlangen-Nürnberg, Paul-Gordan-Str. 6, 91052 Erlangen (Germany); Knipfer, Christian; Rohde, Maximilian [Department of Oral and Maxillofacial Surgery, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, Glueckstrasse 11, 91054 Erlangen (Germany); Tangermann-Gerk, Katja [Bayerisches Laserzentrum GmbH, Konrad-Zuse-Strasse 2-6, 91052 Erlangen (Germany); Schmidt, Michael [Clinical Photonics Lab, Erlangen Graduate School in Advanced Optical Technologies (SAOT), Friedrich-Alexander-Universität Erlangen-Nürnberg, Paul-Gordan-Str. 6, 91052 Erlangen (Germany); Institute of Photonics Technologies, Friedrich-Alexander-Universität Erlangen-Nürnberg, Paul-Gordan-Str. 3, 91052 Erlangen (Germany); Bayerisches Laserzentrum GmbH, Konrad-Zuse-Strasse 2-6, 91052 Erlangen (Germany); and others

    2013-09-01

    This study focuses on tissue differentiation using ‘Laser Induced Breakdown Spectroscopy’ (LIBS) by monitoring the plasma plume created during laser surgery processes. This technique is aimed at controlling a laser surgery feedback system in real time. An Excimer laser (Ar-F 193 nm) was used for the ablation of tissue samples. Fat, muscle, nerve and skin tissue samples of bisected ex-vivo pig heads were prepared as test objects for the ablation procedure. A single fiber was used to collect emissions and deliver them to a spectrometer. The obtained LIBS spectra in the measured emissions were analyzed to determine each tissue type according to their chemical composition. The elements found in the samples and their emission spectra were in agreement with those described in literature. The collected LIBS spectra were analyzed to differentiate the tissues using statistical data analysis: Principal Component Analysis (PCA), Linear Discriminant Analysis (LDA) and Receiver Operating Characteristics (ROC). The obtained preliminary results suggest a successful differentiation of the target tissues with high sensitivity and specificity. The main goal of this study was to qualitatively identify tissue types during laser ablation, which will provide a real time feedback mechanism for clinical Laser surgery applications to significantly improve the accuracy and safety of laser surgery procedures. - Graphical abstract: Skin, fat, muscle and nerve tissue differentiation. - Highlights: • Methods to differentiate tissues for the application in a laser surgery feedback control system • Successful differentiation of the target tissues with high sensitivity and specificity for laser surgery application • Real time feedback mechanism for clinical Laser surgery applications • Laser surgery requirements • Biomedical applications of LIBS.

  19. Spectroscopy: Developments in instrumentation and analysis

    Directory of Open Access Journals (Sweden)

    Dardenne, Pierre

    2002-03-01

    Full Text Available This review presents the characteristics, advantages, limits and potential of three spectroscopic techniques: near-infrared spectroscopy (NIR, mid-infrared spectroscopy (MIR and Raman spectroscopy. The theoretical aspects related with these techniques, the information that can supplied and the main features of the instrumentation are presented and briefly discussed. The last part of the review concerns the application of the spectroscopy to food analysis, with special emphasis on the lipid analysis. The illustrations and examples have been chosen to demonstrate the importance of spectroscopic techniques both in process (on-line control and in laboratories for the analysis of major or minor compounds.Este artículo de revisión presenta las características, ventajas, límites y potencial de tres técnicas espectroscópicas: las espectroscopias del infrarrojo cercano, del medio infrarrojo y Raman. Se presentan, y discuten brevemente, los aspectos teóricos relacionados con estas técnicas, la información que pueden suministrar, y las principales características de la instrumentación. La última parte de la revisión esta dedicada a las aplicaciones de la espectroscopia en análisis de alimentos, con especial énfasis en análisis de lípidos. La ilustraciones y los ejemplos se han elegido para demostrar la importancia de las técnicas espectroscópicas en los procesos en-línea y en los laboratorios en el análisis de componentes mayoritarios y minoritarios.

  20. Pre-flight calibration and initial data processing for the ChemCam laser-induced breakdown spectroscopy instrument on the Mars Science Laboratory rover

    Energy Technology Data Exchange (ETDEWEB)

    Wiens, R.C., E-mail: rwiens@lanl.gov [Los Alamos National Laboratory, Los Alamos, NM 87544 (United States); Maurice, S.; Lasue, J.; Forni, O. [Institut de Recherche en Astrophysique et Planetologie, Toulouse (France); Anderson, R.B. [United States Geological Survey, Flagstaff, AZ (United States); Clegg, S. [Los Alamos National Laboratory, Los Alamos, NM 87544 (United States); Bender, S. [Planetary Science Institute, Tucson, AZ (United States); Blaney, D. [Jet Propulsion Laboratory, Pasadena, CA (United States); Barraclough, B.L. [Planetary Science Institute, Tucson, AZ (United States); Cousin, A. [Los Alamos National Laboratory, Los Alamos, NM 87544 (United States); Institut de Recherche en Astrophysique et Planetologie, Toulouse (France); Deflores, L. [Jet Propulsion Laboratory, Pasadena, CA (United States); Delapp, D. [Los Alamos National Laboratory, Los Alamos, NM 87544 (United States); Dyar, M.D. [Mount Holyoke College, South Hadley, MA (United States); Fabre, C. [Georessources, Nancy (France); Gasnault, O. [Institut de Recherche en Astrophysique et Planetologie, Toulouse (France); Lanza, N. [Los Alamos National Laboratory, Los Alamos, NM 87544 (United States); Mazoyer, J. [LESIA, Observatoire de Paris, Meudon (France); Melikechi, N. [Delaware State University, Dover, DE (United States); Meslin, P.-Y. [Institut de Recherche en Astrophysique et Planetologie, Toulouse (France); Newsom, H. [University of New Mexico, Albuquerque, NM (United States); and others

    2013-04-01

    The ChemCam instrument package on the Mars Science Laboratory rover, Curiosity, is the first planetary science instrument to employ laser-induced breakdown spectroscopy (LIBS) to determine the compositions of geological samples on another planet. Pre-processing of the spectra involves subtracting the ambient light background, removing noise, removing the electron continuum, calibrating for the wavelength, correcting for the variable distance to the target, and applying a wavelength-dependent correction for the instrument response. Further processing of the data uses multivariate and univariate comparisons with a LIBS spectral library developed prior to launch as well as comparisons with several on-board standards post-landing. The level-2 data products include semi-quantitative abundances derived from partial least squares regression. A LIBS spectral library was developed using 69 rock standards in the form of pressed powder disks, glasses, and ceramics to minimize heterogeneity on the scale of the observation (350–550 μm dia.). The standards covered typical compositional ranges of igneous materials and also included sulfates, carbonates, and phyllosilicates. The provenance and elemental and mineralogical compositions of these standards are described. Spectral characteristics of this data set are presented, including the size distribution and integrated irradiances of the plasmas, and a proxy for plasma temperature as a function of distance from the instrument. Two laboratory-based clones of ChemCam reside in Los Alamos and Toulouse for the purpose of adding new spectra to the database as the need arises. Sensitivity to differences in wavelength correlation to spectral channels and spectral resolution has been investigated, indicating that spectral registration needs to be within half a pixel and resolution needs to match within 1.5 to 2.6 pixels. Absolute errors are tabulated for derived compositions of each major element in each standard using PLS regression

  1. High-precision potassium measurements using laser-induced breakdown spectroscopy under high vacuum conditions for in situ K–Ar dating of planetary surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Yuichiro, E-mail: cho@rikkyo.ac.jp [Department of Physics, Rikkyo University, 3-34-1 Nishi-Ikebukuro, Toshima, Tokyo 171-8501 (Japan); Department of Complexity Science and Engineering, University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8561 (Japan); Sugita, Seiji [Department of Complexity Science and Engineering, University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8561 (Japan); Kameda, Shingo [Department of Physics, Rikkyo University, 3-34-1 Nishi-Ikebukuro, Toshima, Tokyo 171-8501 (Japan); Miura, Yayoi N. [Earthquake Research Institute, University of Tokyo, 1-1-1 Yayoi, Bunkyo, Tokyo 113-0032 (Japan); Ishibashi, Ko; Ohno, Sohsuke [Planetary Exploration Research Center, Chiba Institute of Technology, 2-17-1 Tsudanuma, Narashino, Chiba 275-0016 (Japan); Kamata, Shunichi [Hokkaido University Graduate School of Science, 8-2-10 Kita-10 Nishi-8, Kita-ku, Sapporo, Hokkaido 060-0810 (Japan); Arai, Tomoko [Planetary Exploration Research Center, Chiba Institute of Technology, 2-17-1 Tsudanuma, Narashino, Chiba 275-0016 (Japan); Morota, Tomokatsu [Department of Earth and Environmental Sciences, Nagoya University, Furo Chikusa, Nagoya, Aichi 464-8601 (Japan); Namiki, Noriyuki [National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan); Matsui, Takafumi [Planetary Exploration Research Center, Chiba Institute of Technology, 2-17-1 Tsudanuma, Narashino, Chiba 275-0016 (Japan)

    2015-04-01

    We conducted a series of laser induced breakdown spectroscopy (LIBS) experiments for K measurements under high vacuum conditions (10{sup -6} Pa) for the purpose of developing in-situ isochron type K–Ar dating instruments for planetary missions. Unlike whole rock measurement methods, isochron measurements require LIBS experiments in a vacuum chamber because simultaneous Ar isotopic measurements are necessary. However, detailed examination of detection limits and accuracy of this method at low pressures has not been examined extensively before. In this study, the capability of K measurements under high vacuum conditions was examined using LIBS. A compact Czerny-Turner type spectrometer equipped with a charge-coupled device (CCD) as a detector was employed. Twenty-three geologic standard samples were measured using the LIBS method. The second strongest K emission line at 769.89 nm was used for calibration because the strongest emission line at 766.49 nm may suffer from strong interference from another emission line. A calibration curve was constructed for K using internal normalization with the oxygen line at 777 nm and well fitted by a power-law function. Based on the prediction band method, the detection limit and the quantitation limit were estimated to be 300 and 800 ppm, respectively. The 1σ relative uncertainty of the K calibration was 20% for 1 wt.% K{sub 2}O and 40% for 3000 ppm K{sub 2}O. If the amount of Ar is measured with 15% error for the 3.5 billion years rocks containing 1 and 0.3 wt.% K{sub 2}O, the K–Ar ages would be determined with 10% and 20% 1σ errors, respectively. This level of precision will significantly improve the current Martian chronology, which has uncertainty about a factor of two to four. These results indicate that the concentration of K can be measured quantitatively under high vacuum conditions using a combination of instruments that have previously been carried in planetary missions, which suggests the viability of building in

  2. Analysis and comparison of the breakdown performance of semi- insulator and dielectric passivated Si strip detectors

    CERN Document Server

    Ranjan, Kirti; Chatterji, S; Srivastava-Ajay, K; Shivpuri, R K

    2002-01-01

    The harsh radiation environment in future high-energy physics (HEP) experiments like LHC provides a challenging task to the performance of Si microstrip detectors. Normal operating condition for silicon detectors in HEP experiments are in most cases not as favourable as for experiments in nuclear physics. In HEP experiments the detector may be exposed to moisture and other adverse atmospheric environment. It is therefore utmost important to protect the sensitive surfaces against such poisonous effects. These instabilities can be nearly eliminated and the performance of Si detectors can be improved by implementing suitably passivated metal-overhang structures. This paper presents the influence of the relative permittivity of the passivant on the breakdown performance of the Si detectors using computer simulations. The semi-insulator and the dielectric passivated metal-overhang structures are compared under optimal conditions. The influence of various parameters such as passivation layer thickness, junction dep...

  3. The impact of heating the breakdown bubble on the global mode of a swirling jet: Experiments and linear stability analysis

    Science.gov (United States)

    Rukes, Lothar; Sieber, Moritz; Paschereit, C. Oliver; Oberleithner, Kilian

    2016-10-01

    This study investigates the dynamics of non-isothermal swirling jets undergoing vortex breakdown, with an emphasis on helical coherent structures. It is proposed that the dominant helical coherent structure can be suppressed by heating the recirculation bubble. This proposition is assessed with stereo Particle Image Velocimetry (PIV) measurements of the breakdown region of isothermal and heated swirling jets. The coherent kinetic energy of the dominant helical structure was derived from PIV snapshots via proper orthogonal decomposition. For one set of experimental parameters, mild heating is found to increase the energy content of the dominant helical mode. Strong heating leads to a reduction by 30% of the coherent structures energy. For a second set of experimental parameters, no alteration of the dominant coherent structure is detectable. Local linear stability analysis of the time-averaged velocity fields shows that the key difference between the two configurations is the density ratio at the respective wavemaker location. A density ratio of approximately 0.8 is found to correlate to a suppression of the global mode in the experiments. A parametric study with model density and velocity profiles indicates the most important parameters that govern the local absolute growth rate: the density ratio and the relative position of the density profiles and the inner shear layer.

  4. Laser-induced Breakdown Spectroscopy and ablation threshold analysis using a megahertz Yb fiber laser oscillator

    Energy Technology Data Exchange (ETDEWEB)

    Parker, Gregory J.; Parker, Daniel E.; Nie, Bai; Lozovoy, Vadim [Department of Chemistry, Michigan State University, East Lansing, MI 48824 (United States); Dantus, Marcos, E-mail: dantus@msu.edu [Department of Chemistry, Michigan State University, East Lansing, MI 48824 (United States); Department of Physics and Astronomy, Michigan State University, East Lansing, MI 48824 (United States)

    2015-05-01

    A LIBS system is demonstrated using a 100 m cavity Yb fiber oscillator producing ~ 70 ps, 320 nJ clusters of 50–100 fs sub-pulses at 2 MHz. A new empirical model for femtosecond ablation is presented to explain the LIBS signal intensity's non-linear dependence on pulse fluence by accounting for the Gaussian beam's spatial distribution. This model is compared to experimental data and found to be superior to linear threshold fits. This model is then used to measure the ablation threshold of Cu using a typical amplified Ti:sapphire system, and found to reproduce previously reported values to within ~ 20%. The ablation threshold of Cu using the Yb fiber oscillator system was measured to be five times lower than on the amplified Ti:sapphire system. This effect is attributed to the formation of nanostructures on the surface, which have previously been shown to decrease the ablation threshold. The plasma lifetime is found to be ~ 1 ns, much shorter than that of nanosecond ablation, further indicating that the decreased threshold results from surface effects rather than laser–plasma interaction. The low threshold and high pulse energy of the Yb fiber oscillator allows the acquisition of LIBS spectra at megahertz repetition rates. This system could potentially be developed into a compact, fiber-based portable LIBS device taking advantage of the benefits of ultrafast pulses and high repetition rates. - Highlights: • We performed LIBS using a unique ultrafast fiber laser oscillator producing clusters of femtosecond pulses at 2 MHz. • We found the LIBS threshold to be lower than the ablation threshold for single femtosecond laser pulses. • We introduce a model for the LIBS threshold that leads to more accurate determination of threshold values. • We provide results for a number of different solid samples. • The new setup could lead to the design of very compact (portable) and femtosecond-LIBS setups.

  5. IMPLEMENTACIÓN DE TÉCNICAS ESPECTROQUÍMICAS EN LA INVESTIGACIÓN ZOOARQUEOLÓGICA. CUANTIFICACIÓN DE ESTRONCIO UTILIZANDO LASER INDUCED BREAKDOWN SPECTROSCOPY (LIBS)/ Implementation of spectrochemical techniques in zooarchaeological research...

    OpenAIRE

    Gabriela Srur; Andrés D. Izeta; Tobías Schmidt de León; Iván Cabanillas-Vidosa; Ferrero, Juan C.; Gustavo A. Pino

    2012-01-01

    Los estudios químicos sobre restos zooarqueológicos se vienen desarrollando con mayor intensidad en las últimas décadas, especialmente aquellos dedicados a la identificación de huellas químicas o diversos tipos de isótopos y sus relaciones. El objetivo de este trabajo es el de presentar dos procedimientos utilizados para la caracterización química de huesos en base a datos espectrométricos obtenidos mediante la técnica LIBS (Laser Induced Breakdown Spectroscopy). El primero denominado Adición...

  6. Measuring H, O, li, B, and BE on Planetary Surfaces: Calibration of Laser-Induced Breakdown Spectroscopy (libs) Data Under Air, Vacuum, and CO2

    Science.gov (United States)

    Dyar, M. D.; Nelms, M.; Breves, E. A.

    2012-12-01

    Laser-induced breakdown spectrometer (LIBS), as implemented on the ChemCam instrument on Mars Science Lab and the proposed New Frontiers SAGE mission to Venus, can analyze elements from H to Pb from up to 7m standoff. This study examines the capabilities of LIBS to analyze H, O, B, Be, and Li under conditions simulating Earth, the Moon, and Mars. Of these, H is a major constituent of clay minerals and a key indicator of the presence of water. Its abundance in terrestrial materials ranges from 0 ppm up to 10's of wt.% H2O in hydrated sulfates and clays, with prominent emission lines occurring ca. 656.4 nm. O is an important indicator of atmospheric and magmatic coevolution, and has lines ca. 615.8, 656.2, 777.6, and 844.8 nm. Unfortunately there are very few geological samples from which O has been directly measured, but stoichiometry suggests that O varies from ca. 0 wt.% in sulfides to 21% in ferberite, 32% in ilmenite, 42% in amphiboles, 53% in quartz, 63% in melanterite, and 71% in epsomite. Li (lines at 413.3, 460.4, and 670.9 nm in vacuum), B (412.3 nm), and Be (313.1 nm) are highly mobile elements and key indicators of interaction with water. Local atmospheric composition and pressure significantly influence LIBS plasma intensity because the local atmosphere and the breakdown products from the atmospheric species interact with the ablated surface material in the plasma. Measurement of light elements with LIBS requires that spectra be acquired under conditions matching the remote environment. LIBS is critically dependent on the availability of well characterized, homogeneous reference materials that are closely matched in matrix (composition and structure) to the sample being studied. In modern geochemistry, analyses of most major, minor, and trace elements are routinely made. However, quantitative determination of light element concentrations in geological specimens still represents a major analytical challenge. Thus standards for which hydrogen, oxygen, and

  7. Theoretical analysis and design of double implanted MOSFET on 6H silicon carbide wafer for low power dissipation and large breakdown voltage

    Directory of Open Access Journals (Sweden)

    Munish Vashishath

    2008-05-01

    Full Text Available This paper analyses the device structure of a 6H-SiC vertical double-implanted MOSFET (DIMOSFET in order to provide a high breakdown voltage of about 10 kV and a low power dissipation for a rise in device temperature of 600 oC. Analysis of an 800 W power dissipation for stable device operation corresponding to this temperature rise shows optimum doping levels of the drift region lying between 5*1013 cm-3 and 5*1015 cm-3 for a breakdown voltage of 10 kV.

  8. Near infrared spectroscopy in natural products analysis.

    Science.gov (United States)

    Cozzolino, Daniel

    2009-06-01

    Several medicinal and herbal plants properties are related to individual compounds such as essential oils, terpenoids, flavonoids, which are present in natural products in low concentrations (e. g., ppm or ppb). For many years, the use of classical separation and chromatographic and spectrometric techniques such as high performance liquid chromatography (HPLC), gas chromatography (GC), liquid chromatography (LC) and mass spectrometry (MS) were initially used for the elucidation of isolated compounds from different plant matrices. Spectroscopic techniques in the infrared (IR) wavelength region of the electromagnetic spectrum have been used in the food industry to monitor and evaluate the composition of foods. Although Herschel discovered light in the near-infrared (NIR) region as early as 1800, most spectroscopists of the first half of the last century ignored it, in the belief that it lacked any analytical interest. However, during the last 40 years NIR spectroscopy has become one of the most attractive and used methods for analysis. This mini-review highlights recent applications of NIR spectroscopy to the qualitative and quantitative analysis of plant natural products.

  9. Bulk measurement of copper and sodium content in CuIn(0.7)Ga(0.3)Se(2) (CIGS) solar cells with nanosecond pulse length laser induced breakdown spectroscopy (LIBS)

    CERN Document Server

    Kowalczyk, Jeremy M D; DeAngelis, Alexander; Kaneshiro, Jess; Mallory, Stewart A; Chang, Yuancheng; Gaillard, Nicolas

    2013-01-01

    In this work, we show that laser induced breakdown spectroscopy (LIBS) with a nanosecond pulse laser can be used to measure the copper and sodium content of CuIn(0.7)Ga(0.3)Se(2) (CIGS) thin film solar cells on molybdenum. This method has four significant advantages over methods currently being employed: the method is inexpensive, measurements can be taken in times on the order of one second, without high vacuum, and at distances up to 5 meters or more. The final two points allow for in-line monitoring of device fabrication in laboratory or industrial environments. Specifically, we report a linear relationship between the copper and sodium spectral lines from LIBS and the atomic fraction of copper and sodium measured via secondary ion mass spectroscopy (SIMS), discuss the ablation process of this material with a nanosecond pulse laser compared to shorter pulse duration lasers, and examine the depth resolution of nanosecond pulse LIBS.

  10. Determination of Trace Cu in Water by Laser-Induced Breakdown Spectroscopy%水溶液中微量Cu元素的激光诱导光谱检测

    Institute of Scientific and Technical Information of China (English)

    钱惠国; 周卫东

    2012-01-01

    In the present article, the ordinary printing paper was immerged in the aqueous solution of CuCl2, and used as an absorber for the enrichment of heavy metal copper in liquid, After being taken from the solution and dried, the paper was then analyzed using laser-induced breakdown spectroscopy. This method overcomes the drawbacks of splashing and low sensitivity in the process of direct analysis of heavy metal in water sample with LIBS. The Cu 324. 7 ran spectral line was used as the analysis line in experiment The variation in the line intensity at different enrichment time was studied. The calibration curve for the quantitative measurement of Cu in water was established, the detection limit was 0. 023 mg · L‐1, which is about three orders of magnitude improvement compared With that in ordinary LIBS analysis of heavy metal in solution. It is likely that this technique will be practically helpful in the sensitive analysis of the heavy metal in water.%采用普通打印纸作为基底置于含有痕量重金属离子的水溶液中,用于富集溶液中的重金属Cu元素,烘干后用激光诱导击穿光谱进行定量分析.该方法克服了用激光诱导击穿光谱方法直接分析液相样品中重金属含量时存在水的溅射和灵敏度低等不足.实验中选用324.7nm的光谱线作为分析线,研究了光谱强度与富集时间的关系,建立了用于溶液中Cu元素定量测量的校正曲线,检测限达到0.023mg·L-1.为水体中重金属检测提供了一个可行的具有良好灵敏度分析技术.

  11. [Laser-induced breakdown spectrometer--a new tool for quick analysis of on-the-spot sample in metallurgy].

    Science.gov (United States)

    Yao, Ning-Juan; Chen, Ji-Wen; Yang, Zhi-Jun; Wang, Hai-Zhou

    2007-07-01

    In metallurgical steel making a quick analysis of on-the-spot sample is required to know the process of steel making. A new-type spectrometer, laser-induced breakdown spectrometer developed by ourselves, was presented in the present paper. A Nd : YAG laser with pulse width of nanometer was used as an ionization and excitation source. Emission from the plasma ap-peared when the laser beam was focused on the surface of sample. After it was spectrally resolved by a Paschen-Runge polychromator, detected by photomultiplier detectors, integrated by gate intensifier, and converted by analog-to-digital converter, the final result was transmitted to a computer in order to complete data processing. Compared to the common spectrometer on-the-spot in metallurgy, this instrument allows fast analyis without sample preparation (one minute or less), with high precision and sensitivity, so it is very suitable for the analysis of on-the spot sample in metallurgy. In recent years with the fast development of optical fiber, on-line analysis of liquid steel and dynamical control of metallurgical processing will come true by using this instrument.

  12. Lignin analysis by FT-Raman spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Agarwal, U.P.; Obst, J.R.; Cannon, A.B. [USDA Forest Products Lab., Madison, WI (United States)

    1996-10-01

    Traditional methods of lignin analysis, such as Klason (acid insoluble) lignin determinations, give satisfactory results, are widely accepted, and often are considered as standard analyses. However, the Klason lignin method is laborious and time consuming; it also requires a fairly large-amount of isolated analyte. FT-Raman spectroscopy offers an opportunity to simplify and speed up lignin analyses. FT-Raman data for a number of hardwoods (angiosperms) and softwoods (gymnosperms) are compared with data obtained using other analytical methods, including Klason lignin (with corrections for acid soluble lignin), acetyl bromide, and FT-IR determinations. In addition, 10 different specimens of Nothofagus dombeyii (chosen because of the widely varying syringyl:guaiacyl monomer compositions of their lignins) were also analyzed. Lignin monomer compositions were determined by thioacidolysis of by nitrobenzene oxidation.

  13. NMR spectroscopy: a tool for conformational analysis

    Energy Technology Data Exchange (ETDEWEB)

    Tormena, Claudio F.; Cormanich, Rodrigo A.; Rittner, Roberto, E-mail: rittner@iqm.unicamp.br [Universidade Estadual de Campinas (UNICAMP), SP (Brazil). Inst. de Quimica. Lab. de Fisico-Quimica Organica; Freitas, Matheus P. [Universidade Federal de Lavras (UFLA), MG (Brazil). Dept. de Qumica

    2011-07-01

    The present review deals with the application of NMR data to the conformational analysis of simple organic compounds, together with other experimental methods like infrared spectroscopy and with theoretical calculations. Each sub-section describes the results for a group of compounds which belong to a given organic function like ketones, esters, etc. Studies of a single compound, even of special relevance, were excluded since the main goal of this review is to compare the results for a given function, where different substituents were used or small structural changes were introduced in the substrate, in an attempt to disclose their effects in the conformational equilibrium. Moreover, the huge amount of data available in the literature, on this research field, imposed some limitations which will be detailed in the Introduction, but it can be reminded in advance that these limitations include mostly the period when these results were published. (author)

  14. Single Variable and Multivariate Analysis of Remote Laser-Induced Breakdown Spectra for Prediction of Rb, Sr, Cr, Ba, and V in Igneous Rocks

    Energy Technology Data Exchange (ETDEWEB)

    Clegg, Samuel M [Los Alamos National Laboratory; Wiens, Roger C. [Los Alamos National Laboratory; Speicher, Elly A [MT HOLYOKE COLLEGE; Dyar, Melinda D [MT HOLYOKE COLLEGE; Carmosino, Marco L [MT HOLYOKE COLLEGE

    2010-12-23

    Laser-induced breakdown spectroscopy (LIBS) will be employed by the ChemCam instrument on the Mars Science Laboratory rover Curiosity to obtain UV, VIS, and VNIR atomic emission spectra of surface rocks and soils. LIBS quantitative analysis is complicated by chemical matrix effects related to abundances of neutral and ionized species in the resultant plasma, collisional interactions within plasma, laser-to-sample coupling efficiency, and self-absorption. Atmospheric composition and pressure also influence the intensity of LIBS plasma. These chemical matrix effects influence the ratio of intensity or area of a given emission line to the abundance of the element producing that line. To compensate for these complications, multivariate techniques, specifically partial least-squares regression (PLS), have been utilized to predict major element compositions (>1 wt.% oxide) of rocks, PLS methods regress one or multiple response variables (elemental concentrations) against multiple explanatory variables (intensity at each pixel of the spectrometers). Because PLS utilizes all available explanatory variable and eliminates multicollinearity, it generally performs better than univariate methods for prediction of major elements. However, peaks arising from emissions from trace elements may be masked by peaks of higher intensities from major elements. Thus in PLS regression, wherein a correlation coefficient is determined for each elemental concentration at each spectrometer pixel, trace elements may show high correlation with more intense lines resulting from optical emissions of other elements. This could result in error in predictions of trace element concentrations. Here, results of simple linear regression (SLR) and multivariate PLS-2 regression for determination of trace Rb, Sr, Cr, Ba, and V in igneous rock samples are compared. This study focuses on comparisons using only line intensities rather than peak areas to highlight differences between SLR and PLS.

  15. A multiple gap plasma cathode electron gun and its electron beam analysis in self and trigger breakdown modes

    Science.gov (United States)

    Kumar, Niraj; Pal, Dharmendra Kumar; Jadon, Arvind Singh; Pal, Udit Narayan; Rahaman, Hasibur; Prakash, Ram

    2016-03-01

    In the present paper, a pseudospark discharge based multiple gap plasma cathode electron gun is reported which has been operated separately in self and trigger breakdown modes using two different gases, namely, argon and hydrogen. The beam current and beam energy have been analyzed using a concentric ring diagnostic arrangement. Two distinct electron beams are clearly seen with hollow cathode and conductive phases. The hollow cathode phase has been observed for ˜50 ns where the obtained electron beam is having low beam current density and high energy. While in conductive phase it is high current density and low energy electron beam. It is inferred that in the hollow cathode phase the beam energy is more for the self breakdown case whereas the current density is more for the trigger breakdown case. The tailor made operation of the hollow cathode phase electron beam can play an important role in microwave generation. Up to 30% variation in the electron beam energy has been achieved keeping the same gas and by varying the breakdown mode operations. Also, up to 32% variation in the beam current density has been achieved for the trigger breakdown mode at optimized trigger position by varying the gas type.

  16. Optical and X-ray emission spectroscopy of high-power laser-induced dielectric breakdown in molecular gases and their mixtures.

    Science.gov (United States)

    Babankova, Dagmar; Civis, Svatopluk; Juha, Libor; Bittner, Michal; Cihelka, Jaroslav; Pfeifer, Miroslav; Skala, Jirí; Bartnik, Andrzej; Fiedorowicz, Henryk; Mikolajczyk, Janusz; Ryć, Leszek; Sedivcova, Tereza

    2006-11-09

    Large-scale plasma was created in molecular gases (CO, CO2, N2, H2O) and their mixtures by high-power laser-induced dielectric breakdown (LIDB). Compositions of the mixtures used are those suggested for the early earth's atmosphere of neutral and/or mildly reducing character. Time-integrated optical spectra emitted from the laser spark have been measured and analyzed. The spectra of the plasma generated in the CO-containing mixtures are dominated by emission of both C2 and CN radicals. A vibrational temperature of approximately 10(4) K was determined according to an intensity distribution in a vibronic structure of the CN (B2Sigma(+)u-X2Sigma(+)g) violet band. For comparison, the NH3-CH4-H2-H2O mixture has been irradiated as a model of the strongly reducing version of the early earth's atmosphere. In this mixture, excited CN seems to be significantly less abundant than C2. The LIDB experiments were in the molecular gases carried out not only in the static cell but also using a large, double stream pulse jet (gas puff target) placed in the vacuum interaction chamber. The obtained soft X-ray emission spectra indicate the presence of highly charged atomic ions in the hot core of high-power laser sparks.

  17. On the use of laser induced breakdown spectroscopy to characterize the naturally existing crystal in Pakistan and its optical emission spectrum

    Energy Technology Data Exchange (ETDEWEB)

    Iqbal, Javed; Mahmood, S.; Tufail, Iram; Asghar, H.; Ahmed, R.; Baig, M.A., E-mail: baig@qau.edu.pk

    2015-09-01

    We have used the Laser Induced Breakdown Spectroscopic (LIBS) technique to qualitatively identify the naturally existing transparent crystal as a pure quartz (SiO{sub 2}) by observing its optical emission spectra using a Q-switched Nd:YAG laser, fundamental wavelength at 1064 nm and second harmonic at 532 nm. The spectra were registered using a set of five miniature spectrometers covering the spectral range from 200 nm to 720 nm. The plasma temperature has been calculated in the range from 8500 K to 10,200 K and the electron densities determined from the Stark broadened spectral lines in the range of 1.0 × 10{sup 17} cm{sup −3} to 6.0 × 10{sup 17} cm{sup −3}. We report here the full widths at maximum of the spectral lines associated with the 3p4s {sup 3}P{sub 0,1,2} → 3p{sup 23}P{sub 0,1,2}, {sup 1}S{sub 0}, {sup 1}D{sub 2} transitions in Si and four multiplets of singly ionized silicon. - Highlights: • Characterization of naturally existing transparent crystal as pure quartz (SiO{sub 2}) using LIBS. • Determination of plasma parameters and full width at half maximum of the neutral and singly ionized silicon lines. • Confirmation of optically thin plasma validity of LTE.

  18. 脐橙果皮镉铅含量激光诱导无损检测试验%Nondestructive determination for concentration of Pb and Cd in navel orange peel by laser induced breakdown spectroscopy

    Institute of Scientific and Technical Information of China (English)

    张旭; 姚明印; 刘木华

    2013-01-01

      为了验证激光诱导击穿光谱(LIBS)快速无损检测农产品中重金属污染物的可行性,对赣南脐橙样品进行了实验室镉铅污染处理.首先对样品 LIBS 试验参数进行了优化分析,根据美国 NIST(National Institute of Standards and Technology)原子光谱数据库,确定试验用的最佳特征谱线位置分别为 Cd 226.502 nm 和 Pb 405.783 nm.观测了光谱信噪比和强度随着延迟时间和激光能量的变化规律,综合考虑结果表明,最佳延迟时间和激光能量分别为1300 ns 和130 mJ.利用优化的 LIBS 试验参数对镉(Cd)和铅(Pb)元素的光谱信息进行了采集.同时,采用原子吸收分光光度计对脐橙表皮中镉铅元素的真实浓度进行了检测,建立了镉铅元素特征谱线强度与真实浓度之间的关系模型,相关系数分别为0.94669和0.96059.由定标模型得到镉铅元素的检测限分别为17.375和22.782µg/g.为了验证模型的准确性,采用3个样品做了定标曲线反演分析,预测值与真实值之间的相对误差保持在10%左右.试验结果表明,LIBS 技术能应用于农业安全方面的农产品重金属 Cd、Pb的快速无损检测.%Toxic heavy metal cadmium (Cd) and lead (Pb) are found in water and soil primarily due to the effluents of industrial wastewater. Primary products may be contaminated by heavy metal Cd and Pb, which are not essential elements in the human body, and may bring harm to human. In this case, it is necessary to determine Cd and Pb concentration in primary products for the evaluation of nutritional status and the optimization of the growing conditions. The traditional techniques in determining heavy metals require consumption of time and/or reagent, sample preparation as well as laboratory analysis environment. Laser-induced breakdown spectroscopy (LIBS) is a form of atomic emission spectroscopy based on plasma induced by focusing a laser pulse on the sample surface. LIBS has the characteristics such as

  19. Raman spectroscopy in the analysis of food and pharmaceutical nanomaterials

    OpenAIRE

    Ying-Sing Li; Church, Jeffrey S.

    2014-01-01

    Raman scattering is an inelastic phenomenon. Although its cross section is very small, recent advances in electronics, lasers, optics, and nanotechnology have made Raman spectroscopy suitable in many areas of application. The present article reviews the applications of Raman spectroscopy in food and drug analysis and inspection, including those associated with nanomaterials. Brief overviews of basic Raman scattering theory, instrumentation, and statistical data analysis are also given. With t...

  20. Experimental Study on Chromium in Gannan Navel Orange by Laser-Induced Breakdown Spectroscopy%激光击穿光谱检测赣南脐橙中铬元素的实验研究

    Institute of Scientific and Technical Information of China (English)

    徐媛; 刘木华; 姚明印; 彭秋梅; 陈添兵; 张旭; 林永增

    2012-01-01

    It is a relatively new task to apply the laser induced breakdown spectroscopy (LIBS) to fruit samples. To apply LIBS technique in the field related to analysis of trace heavy metal element in fruits samples, we have done primary experiments using Gannan navel orange samples. The authors put the samples into different concentration gradient K2 Cr2 O7 solution and left it for 30 hours, and then we did the LIBS experiment, discriminated characteristic spectra of chromium element and recorded the peak intensity information. Weighing three grams of sample and determined chromium concentration in the samples by atomic absorption spectrophotometer using wet digestion. The calibration curve of the line intensities versus the concentrations of the Cr element was acquired by the Origin software. The authors found that the linear correlation coefficient is 0. 981 66. The calibration curve can be used for the quantitative analysis of chromium element with an unknown concentration in Gannan navel orange. The LIBS detection limit of Cr in the solution was 11. 64 mg · g‐1 from the measured calibration curve. Experiment results showed that LIBS technique is a valid means for measuring and quantitatively analyzing the content of heavy metal elements in fruit samples.%为评估激光诱导击穿光谱技术(LIBS)对水果样品中重金属元素的检测潜力,选用在不同浓度梯度重铬酸钾水溶液中浸泡了30个小时的赣南脐橙样品进行LIBS实验,采集铬元素的特征谱线与峰值强度信息.在激光照射部位称取3 g左右的脐橙样品进行湿法消解,用原子分光光度计检测样品中的铬浓度.实验数据用Origin软件进行拟合后得到了谱线峰值强度和Cr浓度之间的关系曲线,即定标曲线,二者有线性关系,线性相关度0.98166.由检测限公式计算得到铬浓度的检测限为11.68 μg·g-1.采用该定标曲线即可对赣南脐橙中的铬元素进行定量检测.实验结果表明LIBS技术是一种

  1. Correcting for variable laser-target distances of laser-induced breakdown spectroscopy measurements with ChemCam using emission lines of Martian dust spectra

    Energy Technology Data Exchange (ETDEWEB)

    Melikechi, N.; Mezzacappa, A. [Optical Science Center for Applied Research, Delaware State University, Dover, DE (United States); Cousin, A.; Lanza, N.L. [Los Alamos National Laboratory, Los Alamos, NM (United States); Lasue, J. [Institut de Recherche en Astophysique et Planetologie (IRAP), Universite' Paul Sabatier, Toulouse (France); Clegg, S.M. [Los Alamos National Laboratory, Los Alamos, NM (United States); Berger, G. [Institut de Recherche en Astophysique et Planetologie (IRAP), Universite' Paul Sabatier, Toulouse (France); Wiens, R.C. [Los Alamos National Laboratory, Los Alamos, NM (United States); Maurice, S. [Institut de Recherche en Astophysique et Planetologie (IRAP), Universite' Paul Sabatier, Toulouse (France); Tokar, R.L.; Bender, S. [Planetary Science Institute, Flagstaff, AZ (United States); Forni, O. [Institut de Recherche en Astophysique et Planetologie (IRAP), Universite' Paul Sabatier, Toulouse (France); Breves, E.A.; Dyar, M.D. [Dept. of Astronomy, Mount Holyoke College, South Hadley, MA (United States); Frydenvang, J. [The Niels Bohr Institute, University of Copenhagen, Copenhagen (Denmark); Delapp, D. [Los Alamos National Laboratory, Los Alamos, NM (United States); Gasnault, O. [Institut de Recherche en Astophysique et Planetologie (IRAP), Universite' Paul Sabatier, Toulouse (France); Newsom, H.; Ollila, A.M. [Earth and Planetary Sciences, University of New Mexico, Alburquerque, NM (United States); Lewin, E. [Institut des Sciences de la Terre, Universite Grenoble l-CNRS, Grenoble (France); and others

    2014-06-01

    As part of the Mars Science Laboratory, the ChemCam instrument acquires remote laser induced breakdown spectra at distances that vary between 1.56 m and 7 m. This variation in distance affects the intensities of the measured LIBS emission lines in non-trivial ways. To determine the behavior of a LIBS emission line with distance, it is necessary to separate the effects of many parameters such as laser energy, laser spot size, target homogeneity, and optical collection efficiency. These parameters may be controlled in a laboratory on Earth but for field applications or in space this is a challenge. In this paper, we show that carefully selected ChemCam LIBS emission lines acquired from the Martian dust can be used to build an internal proxy spectroscopic standard. This in turn, allows for a direct measurement of the effects of the distance of various LIBS emission lines and hence can be used to correct ChemCam LIBS spectra for distance variations. When tested on pre-launch LIBS calibration data acquired under Martian-like conditions and with controlled and well-calibrated targets, this approach yields much improved agreement between targets observed at various distances. This work lays the foundation for future implementation of automated routines to correct ChemCam spectra for differences caused by variable distance. - Highlights: • Selected Martian dust emission lines are used to correct for variable laser-target distances. • The correction model yields improved agreement between targets observed at various distances. • The impact of the model reduces the bias between predicted and actual compositions by as much as 70%. • When implemented, the model will yield spectral corrections for various ChemCam measurements. • This work is a foundation to perform novel stand-off LIBS measurements on Earth and other planets.

  2. TCAD analysis of the leakage current and breakdown versus temperature of GaN-on-Silicon vertical structures

    Science.gov (United States)

    Cornigli, Davide; Monti, Federico; Reggiani, Susanna; Gnani, Elena; Gnudi, Antonio; Baccarani, Giorgio

    2016-01-01

    A TCAD-based approach has been used to investigate the leakage current and breakdown regime of vertical GaN/AlGaN/Si structures at different ambient temperatures. TCAD modeling has been used to assess possible mechanisms of the forward-bias leakage current. A good agreement with experimental data has been obtained by implementing both trap-assisted and Poole-Frenkel conduction mechanisms into the deeper buffer layers, indicating that conduction is dominated by electron injection from silicon into a continuum of states at a given energy offset in the transition layer, which might be associated with conductive dislocation defects. The latter mechanisms have been proven to anticipate the onset of breakdown at high temperatures.

  3. IMPLEMENTACIÓN DE TÉCNICAS ESPECTROQUÍMICAS EN LA INVESTIGACIÓN ZOOARQUEOLÓGICA. CUANTIFICACIÓN DE ESTRONCIO UTILIZANDO LASER INDUCED BREAKDOWN SPECTROSCOPY (LIBS/ Implementation of spectrochemical techniques in zooarchaeological research...

    Directory of Open Access Journals (Sweden)

    Gabriela Srur

    2012-11-01

    Full Text Available Los estudios químicos sobre restos zooarqueológicos se vienen desarrollando con mayor intensidad en las últimas décadas, especialmente aquellos dedicados a la identificación de huellas químicas o diversos tipos de isótopos y sus relaciones. El objetivo de este trabajo es el de presentar dos procedimientos utilizados para la caracterización química de huesos en base a datos espectrométricos obtenidos mediante la técnica LIBS (Laser Induced Breakdown Spectroscopy. El primero denominado Adición Estándar, consiste en un procedimiento destructivo, con un grado de error estimable, mientras que el segundo, Reemplazo de la Matriz Ósea, constituye un método no invasivo y con un grado de error relativamente bajo. Con esto se espera lograr el desarrollo de un corpus metodológico y analítico que permita caracterizar de un modo eficiente y económico las huellas químicas de diverso material arqueofaunístico. En este sentido se intenta lograr una caracterización química de huesos arqueológicos con el fin de dar respuesta a cuestiones relacionadas tanto a la alimentación como a la movilidad de los animales en el pasado. Abstract Chemical studies on zooarchaeological remains have been most extensively developed in recent decades, especially those focused on the identification of chemical fingerprints or types of isotopes and their relationships. This paper aims at showing two procedures used for chemical characterization of bones on the basis of spectrometric data obtained by LIBS technique (Laser Induced Breakdown Spectroscopy. One called Standard Addition, a destructive procedure, with a high error degree; the other called Bone Matrix Replacement, a noninvasive method with a relatively low error degree. We expect to gather a methodological and analytical corpus to characterize, efficiently and inexpensively, the chemical fingerprints of diverse archaeofaunal material. Hence, we intend to achieve chemical characterization of

  4. Spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Hellman, Hal

    1968-01-01

    This booklet discusses spectroscopy, the study of absorption of radiation by matter, including X-ray, gamma-ray, microwave, mass spectroscopy, as well as others. Spectroscopy has produced more fundamental information to the study of the detailed structure of matter than any other tools.

  5. Advances in Mid-Infrared Spectroscopy for Chemical Analysis

    Science.gov (United States)

    Haas, Julian; Mizaikoff, Boris

    2016-06-01

    Infrared spectroscopy in the 3-20 μm spectral window has evolved from a routine laboratory technique into a state-of-the-art spectroscopy and sensing tool by benefitting from recent progress in increasingly sophisticated spectra acquisition techniques and advanced materials for generating, guiding, and detecting mid-infrared (MIR) radiation. Today, MIR spectroscopy provides molecular information with trace to ultratrace sensitivity, fast data acquisition rates, and high spectral resolution catering to demanding applications in bioanalytics, for example, and to improved routine analysis. In addition to advances in miniaturized device technology without sacrificing analytical performance, selected innovative applications for MIR spectroscopy ranging from process analysis to biotechnology and medical diagnostics are highlighted in this review.

  6. Spectroscopy

    CERN Document Server

    Walker, S

    1976-01-01

    The three volumes of Spectroscopy constitute the one comprehensive text available on the principles, practice and applications of spectroscopy. By giving full accounts of those spectroscopic techniques only recently introduced into student courses - such as Mössbauer spectroscopy and photoelectron spectroscopy - in addition to those techniques long recognised as being essential in chemistry teaching - sucha as e.s.r. and infrared spectroscopy - the book caters for the complete requirements of undergraduate students and at the same time provides a sound introduction to special topics for graduate students.

  7. Electrodynamic thermal breakdown of a capacitor insulator

    Science.gov (United States)

    Emel'Yanov, O. A.

    2011-11-01

    A mechanism of the electrical breakdown is proposed for modern metal-field capacitors with the well-known property of self-healing of the breakdown strength. Upon an increase in the working voltage, the self-healing time increases to tens of microseconds, and the heating of adjacent insulator layers becomes significant. The propagating thermally activated conduction wave facilitates the enhancement of the electric field up to breakdown values. Analysis of the dynamics of electric field increase is carried out for capacitors based on polyethylene terephthalate (PET) dielectric.

  8. Raman spectroscopy for analysis of thorium compounds

    Science.gov (United States)

    Su, Yin-Fong; Johnson, Timothy J.; Olsen, Khris B.

    2016-05-01

    The thorium fuel cycle is an alternative to the uranium fuel cycle in that when 232Th is irradiated with neutrons it is converted to 233U, another fissile isotope. There are several chemical forms of thorium which are used in the Th fuel cycle. Recently, Raman spectroscopy has become a very portable and facile analytical technique useful for many applications, including e.g. determining the chemical composition of different materials such as for thorium compounds. The technique continues to improve with the development of ever-more sensitive instrumentation and better software. Using a laboratory Fourier-transform (FT)-Raman spectrometer with a 785 nm wavelength laser, we were able to obtain Raman spectra from a series of thorium-bearing compounds of unknown origin. These spectra were compared to the spectra of in-stock-laboratory thorium compounds including e.g. ThO2, ThF4, Th(CO3)2 and Th(C2O4)2. The unknown spectra showed very good agreement to the known standards, demonstrating the applicability of Raman spectroscopy for detection and identification of these nuclear materials.

  9. Raman Spectroscopy for Analysis of Thorium Compounds

    Energy Technology Data Exchange (ETDEWEB)

    Su, Yin-Fong; Johnson, Timothy J.; Olsen, Khris B.

    2016-05-12

    The thorium fuel cycle is an alternative to the uranium fuel cycle in that when 232Th is irradiated with neutrons it is converted to 233U, another fissile isotope. There are several chemical forms of thorium which are used in the Th fuel cycle. Recently, Raman spectroscopy has become a very portable and facile analytical technique useful for many applications, including e.g. determining the chemical composition of different materials such as for thorium compounds. The technique continues to improve with the development of ever-more sensitive instrumentation and better software. Using a laboratory Fourier-transform (FT)-Raman spectrometer with a 785 nm wavelength laser, we were able to obtain Raman spectra from a series of thorium-bearing compounds of unknown origin. These spectra were compared to the spectra of in-stock-laboratory thorium compounds including ThO2, ThF4, Th(CO3)2 and Th(C2O4)2. The unknown spectra showed very good agreement to the known standards, demonstrating the applicability of Raman spectroscopy for detection and identification of these nuclear materials.

  10. Analysis Tools for Next-Generation Hadron Spectroscopy Experiments

    CERN Document Server

    Battaglieri, M; Celentano, A; Chung, S -U; D'Angelo, A; De Vita, R; Döring, M; Dudek, J; Eidelman, S; Fegan, S; Ferretti, J; Fox, G; Galata, G; Garcia-Tecocoatzi, H; Glazier, D I; Grube, B; Hanhart, C; Hoferichter, M; Hughes, S M; Ireland, D G; Ketzer, B; Klein, F J; Kubis, B; Liu, B; Masjuan, P; Mathieu, V; McKinnon, B; Mitchell, R; Nerling, F; Paul, S; Pelaez, J R; Rademacker, J; Rizzo, A; Salgado, C; Santopinto, E; Sarantsev, A V; Sato, T; Schlüter, T; da Silva, M L L; Stankovic, I; Strakovsky, I; Szczepaniak, A; Vassallo, A; Walford, N K; Watts, D P; Zana, L

    2014-01-01

    The series of workshops on New Partial-Wave Analysis Tools for Next-Generation Hadron Spectroscopy Experiments was initiated with the ATHOS 2012 meeting, which took place in Camogli, Italy, June 20-22, 2012. It was followed by ATHOS 2013 in Kloster Seeon near Munich, Germany, May 21-24, 2013. The third, ATHOS3, meeting is planned for April 13-17, 2015 at The George Washington University Virginia Science and Technology Campus, USA. The workshops focus on the development of amplitude analysis tools for meson and baryon spectroscopy, and complement other programs in hadron spectroscopy organized in the recent past including the INT-JLab Workshop on Hadron Spectroscopy in Seattle in 2009, the International Workshop on Amplitude Analysis in Hadron Spectroscopy at the ECT*-Trento in 2011, the School on Amplitude Analysis in Modern Physics in Bad Honnef in 2011, the Jefferson Lab Advanced Study Institute Summer School in 2012, and the School on Concepts of Modern Amplitude Analysis Techniques in Flecken-Zechlin near...

  11. Spectroscopic Study of Laser Induced Breakdown Plasma Spectroscopy in Air and Semi-Empirical Simulation%激光诱导击穿空气等离子体光谱及半经验理论模拟

    Institute of Scientific and Technical Information of China (English)

    孙对兄; 苏茂根; 董晨钟; 马云云; 杨峰; 曹世权

    2014-01-01

    A laser induced breakdown spectroscopy experiment was carried out using Nd ∶ YAG laser in air ,and time-resolved spectra were measured .Based on local thermodynamic equilibrium assumption ,a method used to simulate LIBS spectra is pro-posed .A LIBS spectrum of air in the wavelength range of 700~900 nm was simulated using this method .A good agreement be-tween experiment and simulation was obtained ,and moreover ,the relative concentrations of the N ,O and Ar in air were ob-tained .%利用Nd∶YAG激光器输出的1064 nm激光进行了激光诱导击穿空气光谱实验,测量了空气等离子体的时间分辨光谱。基于局域热动力学平衡模型,建立了模拟激光诱导击穿光谱的方法。对700~900 nm波段的空气等离子体光谱进行了模拟。通过模拟结果与实验结果的比较,进一步估算出了空气中氮、氧和氩的相对含量。

  12. Drug stability analysis by Raman spectroscopy.

    Science.gov (United States)

    Shende, Chetan