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Sample records for inductively coupled multiple

  1. Iron-Isotopic Fractionation Studies Using Multiple Collector Inductively Coupled Plasma Mass Spectrometry

    NASA Technical Reports Server (NTRS)

    Anbar, A. D.; Zhang, C.; Barling, J.; Roe, J. E.; Nealson, K. H.

    1999-01-01

    The importance of Fe biogeochemistry has stimulated interest in Fe isotope fractionation. Recent studies using thermal ionization mass spectrometry (TIMS) and a "double spike" demonstrate the existence of biogenic Fe isotope effects. Here, we assess the utility of multiple-collector inductively-coupled plasma mass spectrometry(MC-ICP-MS) with a desolvating sample introduction system for Fe isotope studies, and present data on Fe biominerals produced by a thermophilic bacterium. Additional information is contained in the original extended abstract.

  2. Recent developments in inductively coupled plasma source magnetic sector multiple collector mass spectrometry

    SciTech Connect

    Halliday, A.N.; Lee, Der-Chuen; Christensen, J.C.; Jones, C.E.; Hall, C.M.; Yi, Wen; Teagle, D.; Walder, A.J.; Freedman, P.A.

    1994-11-01

    This paper describes advances in isotopic measurements that have been made with an inductively coupled plasma source magnetic sector multiple collector mass spectrometer and presents results of new experiments aimed at further evaluating the instrument`s capability. It is shown using standard solutions that trace element ratios such as Rb/Sr can be measured precisely without isotope dilution by comparison with reference solutions of known composition. Similarly, using a new wide flight tube, Pb isotopic compositions and U/Pb ratios can be accurately measured simultaneously without isotope dilution. The effects of deliberately inducing changes in the running conditions (RF power) are shown to be significant for measuring trace element ratios but not for mass bias and interference corrected isotopic compositions. Finally, it is demonstrated that precise and accurate isotopic compositions of elements as refractory as W can be determined relatively easily by solution nebulization and even by direct laser ablation of complex silicates. Isobaric interferences in such experiments are negligible. These experiments serve to highlight the remarkable potential that this new field offers for hitherto difficult isotopic measurements in nuclear, earth, environmental and medical sciences. Isotopic measurements can be made that are reproducible at high precision through a range of running conditions, even in the presence of isobaric interferences. The ability to correct for mass discrimination accurately using a second element of similar mass, the very high sensitivity for elements that are otherwise difficult to ionize, the demonstrated capability for laser ablation work and the ability to measure through a wide mass range simultaneously give this instrument major advantages over other more traditional techniques of isotopic measurement.

  3. On the possibility of the multiple inductively coupled plasma and helicon plasma sources for large-area processes

    SciTech Connect

    Lee, Jin-Won; Lee, Yun-Seong Chang, Hong-Young; An, Sang-Hyuk

    2014-08-15

    In this study, we attempted to determine the possibility of multiple inductively coupled plasma (ICP) and helicon plasma sources for large-area processes. Experiments were performed with the one and two coils to measure plasma and electrical parameters, and a circuit simulation was performed to measure the current at each coil in the 2-coil experiment. Based on the result, we could determine the possibility of multiple ICP sources due to a direct change of impedance due to current and saturation of impedance due to the skin-depth effect. However, a helicon plasma source is difficult to adapt to the multiple sources due to the consistent change of real impedance due to mode transition and the low uniformity of the B-field confinement. As a result, it is expected that ICP can be adapted to multiple sources for large-area processes.

  4. High-precision measurement of variations in calcium isotope ratios in urine by multiple collector inductively coupled plasma mass spectrometry

    USGS Publications Warehouse

    Morgan, J.L.L.; Gordon, G.W.; Arrua, R.C.; Skulan, J.L.; Anbar, A.D.; Bullen, T.D.

    2011-01-01

    We describe a new chemical separation method to isolate Ca from other matrix elements in biological samples, developed with the long-term goal of making high-precision measurement of natural stable Ca isotope variations a clinically applicable tool to assess bone mineral balance. A new two-column procedure utilizing HBr achieves the purity required to accurately and precisely measure two Ca isotope ratios (44Ca/42Ca and 44Ca/43Ca) on a Neptune multiple collector inductively coupled plasma mass spectrometer (MC-ICPMS) in urine. Purification requirements for Sr, Ti, and K (Ca/Sr > 10000; Ca/Ti > 10000000; and Ca/K > 10) were determined by addition of these elements to Ca standards of known isotopic composition. Accuracy was determined by (1) comparing Ca isotope results for samples and standards to published data obtained using thermal ionization mass spectrometry (TIMS), (2) adding a Ca standard of known isotopic composition to a urine sample purified of Ca, and (3) analyzing mixtures of urine samples and standards in varying proportions. The accuracy and precision of δ44/42Ca measurements of purified samples containing 25 μg of Ca can be determined with typical errors less than ±0.2‰ (2σ).

  5. Comparison of thermal ionization mass spectrometry and Multiple Collector Inductively Coupled Plasma Mass Spectrometry for cesium isotope ratio measurements

    NASA Astrophysics Data System (ADS)

    Isnard, H.; Granet, M.; Caussignac, C.; Ducarme, E.; Nonell, A.; Tran, B.; Chartier, F.

    2009-11-01

    In the nuclear domain, precise and accurate isotopic composition determination of elements in spent nuclear fuels is mandatory to validate neutron calculation codes and for nuclear waste disposal. The present study presents the results obtained on Cs isotope ratio by mass spectrometric measurements. Natural cesium is monoisotopic ( 133Cs) whereas cesium in spent fuels has 4 isotopes ( 133Cs, 134Cs, 135Cs, and 137Cs). As no standard reference material is available to evaluate the accuracy of Cs isotopic measurements, a comparison of cesium isotopic composition in spent nuclear fuels has been performed between Thermal Ionization Mass Spectrometry (TIMS) and a new method involving Multiple Collector Inductively Coupled Plasma Mass Spectrometry (MC-ICPMS) measurements. For TIMS measurements, isotopic fractionation has been evaluated by studying the behavior of cesium isotope ratios ( 133Cs/ 137Cs and 135Cs/ 137Cs) during the analyses. For MC-ICPMS measurements, the mass bias effects have been corrected with an external mass bias correction using elements (Eu and Sb) close to cesium masses. The results obtained by the two techniques show good agreement: relative difference on 133Cs/ 137Cs and 135Cs/ 137Cs ratios for two nuclear samples, analyzed after chemical separation, ranges from 0.2% to 0.5% depending on the choice of reference value for mass bias correction by MC-ICPMS. Finally the quantification of the 135Cs/ 238U ratio by the isotope dilution technique is presented in the case of a MOx (mixed oxide) spent fuel sample. Evaluation of the global uncertainties shows that this ratio could be defined at an uncertainty of 0.5% ( k = 2). The intercomparison between two independent mass spectrometric techniques is fundamental for the evaluation of uncertainty when no isotopic standard is available.

  6. Matrix effects of calcium on high-precision sulfur isotope measurement by multiple-collector inductively coupled plasma mass spectrometry.

    PubMed

    Liu, Chenhui; Bian, Xiao-Peng; Yang, Tao; Lin, An-Jun; Jiang, Shao-Yong

    2016-05-01

    Multiple-collector inductively coupled plasma mass spectrometry (MC-ICP-MS) has been successfully applied in the rapid and high-precision measurement for sulfur isotope ratios in recent years. During the measurement, the presence of matrix elements would affect the instrumental mass bias for sulfur and these matrix-induced effects have aroused a lot of researchers' interest. However, these studies have placed more weight on highlighting the necessity for their proposed correction protocols (e.g., chemical purification and matrix-matching) while less attention on the key property of the matrix element gives rise to the matrix effects. In this study, four groups of sulfate solutions, which have different concentrations of sulfur (0.05-0.60mM) but a constant sequence of atomic calcium/sulfur ratios (0.1-50), are investigated under wet (solution) and dry (desolvation) plasma conditions to make a detailed evaluation on the matrix effects from calcium on sulfur isotope measurement. Based on a series of comparative analyses, we indicated that, the matrix effects of calcium on both measured sulfur isotope ratios and detected (32)S signal intensities are dependent mainly on the absolute calcium concentration rather than its relative concentration ratio to sulfur (i.e., atomic calcium/sulfur ratio). Also, for the same group of samples, the matrix effects of calcium under dry plasma condition are much more significant than that of wet plasma. This research affords the opportunity to realize direct and relatively precise sulfur isotope measurement for evaporite gypsum, and further provides some suggestions with regard to sulfur isotope analytical protocols for sedimentary pore water. PMID:26946020

  7. Capacitively-coupled inductive sensor

    DOEpatents

    Ekdahl, Carl A.

    1984-01-01

    A capacitively coupled inductive shunt current sensor which utilizes capacitive coupling between flanges having an annular inductive channel formed therein. A voltage dividing capacitor is connected between the coupling capacitor and ground to provide immediate capacitive division of the output signal so as to provide a high frequency response of the current pulse to be detected. The present invention can be used in any desired outer conductor such as the outer conductor of a coaxial transmission line, the outer conductor of an electron beam transmission line, etc.

  8. Precise isotopic analysis of Mo in seawater using multiple collector-inductively coupled mass spectrometry coupled with a chelating resin column preconcentration method.

    PubMed

    Nakagawa, Yusuke; Firdaus, M Lutfi; Norisuye, Kazuhiro; Sohrin, Yoshiki; Irisawa, Keita; Hirata, Takafumi

    2008-12-01

    It is widely recognized that the natural isotopic variation of Mo can provide crucial information about the geochemical circulation of Mo, and the ocean is an important reservoir of Mo. To obtain precise isotopic data on Mo in seawater samples using multiple collector-inductively coupled plasma mass spectrometry (MC-ICPMS), we have developed a preconcentration technique using 8-hydroxyquinoline bonded covalently to a vinyl polymer resin (TSK-8HQ). By optimizing the procedure, Mo in seawater could be effectively separated from matrix elements such as alkali, alkaline earth, and transition metals. With this technique, even with a 50-fold enrichment factor, the changes in the 98Mo/95Mo ratio during preconcentration were smaller than twice the standard deviation (SD) in this study. Mass discrimination of Mo isotopes during the measurement was externally corrected for by normalizing 86Sr/88Sr to 0.1194 using an exponential law. We evaluated delta98/95Mo to a precision of +/- 0.08 per thousand (+/-2 SD); this value was found to be less than one-third of previous reported values. Moreover, we were able to determine an accurate ratio for every pair of stable Mo isotopes, which was impossible with previous methods owing to the isobaric interference from the external elements (Zr and Ru). In this study, delta92/98Mo in seawater was first determined so that it had the smallest relative error. We applied the proposed method to four kinds of seawater samples. The Mo compositions were constant among them, with average delta98/95Mo and delta92/98Mo values of 2.45 +/- 0.11 and -4.94 +/- 0.09 per thousand (+/-2 SD), respectively. Our data indicate that seawater is enriched in heavy Mo isotopes than previously reported. PMID:19551942

  9. Considerations in the Application of Multiple Ion Counting for the Trace Analysis of Plutonium and Uranium Isotope Ratios Using Thermal Ionization and Inductively-Coupled Plasma Mass Spectrometry

    NASA Astrophysics Data System (ADS)

    Riciputi, L. R.

    2008-12-01

    The use of simultaneous multiple-ion counting for the analysis of small samples of plutonium and uranium has been investigated using three different instruments, the ThermoElectron Neptune inductively-coupled plasma mass spectrometer, the ThermoElectron Triton thermal ionization mass spectrometer, and the Isotopex Iso-T thermal ionization mass spectrometer. The Neptune and Triton instruments utilize identical multiple ion counter arrays, with ions impinging directly on the channeltron surface. The Isotopex instruments utilize a different style of channeltron detector. The most significant difference in the Isotopex detectors is the presence of a conversion dynode at the entrance to the channeltron. Results suggest that the performance of the ThermoElectron MIC system varies between the Neptune and Triton instruments, which probably reflects both differences in the inherent characteristics of plasma and thermal sources and the performance of the MICS themselves. Differences in performance and stability between the '"naked"' and conversion dynode equipped channeltrons on the two thermal ionization instruments support these observations. These differences suggest that different analytical approaches to calibration of the multiple-ion counters may be required. Differences in potential analytical strategies employing multiple ion counters on the different instruments, including calibration schemes, precision and accuracy limits, and analytical strategies that can be employed, will be discussed. Results from both thermal ionization and inductively-coupled plasma sources suggest that the dominant source of uncertainty in isotope ratio measurement using multiple ion counting shifts from counting limitations for very small signals to uncertainties in gain calibration and detector drift among the ion counters at higher count rates. These characteristics place limits on the applicability of multiple ion counters; results from mixed Faraday/multiple ion counting analysis will

  10. High precision and high accuracy isotopic measurement of uranium using lead and thorium calibration solutions by inductively coupled plasma-multiple collector-mass spectrometry

    SciTech Connect

    Bowen, I.; Walder, A.J.; Hodgson, T.; Parrish, R.R. |

    1998-12-31

    A novel method for the high accuracy and high precision measurement of uranium isotopic composition by Inductively Coupled Plasma-Multiple Collector-Mass Spectrometry is discussed. Uranium isotopic samples are spiked with either thorium or lead for use as internal calibration reference materials. This method eliminates the necessity to periodically measure uranium standards to correct for changing mass bias when samples are measured over long time periods. This technique has generated among the highest levels of analytical precision on both the major and minor isotopes of uranium. Sample throughput has also been demonstrated to exceed Thermal Ionization Mass Spectrometry by a factor of four to five.

  11. Inductively coupled helium plasma torch

    SciTech Connect

    Montaser, Akbar; Chan, Shi-Kit; Van Hoven, Raymond L.

    1989-01-01

    An inductively coupled plasma torch including a base member, a plasma tube and a threaded insert member within the plasma tube for directing the plasma gas in a tangential flow pattern. The design of the torch eliminates the need for a separate coolant gas tube. The torch can be readily assembled and disassembled with a high degree of alignment accuracy.

  12. Closed inductively coupled plasma cell

    DOEpatents

    Manning, T.J.; Palmer, B.A.; Hof, D.E.

    1990-11-06

    A closed inductively coupled plasma cell generates a relatively high power, low noise plasma for use in spectroscopic studies is disclosed. A variety of gases can be selected to form the plasma to minimize spectroscopic interference and to provide a electron density and temperature range for the sample to be analyzed. Grounded conductors are placed at the tube ends and axially displaced from the inductive coil, whereby the resulting electromagnetic field acts to elongate the plasma in the tube. Sample materials can be injected in the plasma to be excited for spectroscopy. 1 fig.

  13. Closed inductively coupled plasma cell

    DOEpatents

    Manning, Thomas J.; Palmer, Byron A.; Hof, Douglas E.

    1990-01-01

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

  14. Mobile inductively coupled plasma system

    DOEpatents

    D`Silva, A.P.; Jaselskis, E.J.

    1999-03-30

    A system is described for sampling and analyzing a material located at a hazardous site. A laser located remotely from the hazardous site is connected to an optical fiber, which directs laser radiation proximate the material at the hazardous site. The laser radiation abates a sample of the material. An inductively coupled plasma is located remotely from the material. An aerosol transport system carries the ablated particles to a plasma, where they are dissociated, atomized and excited to provide characteristic optical reduction of the elemental constituents of the sample. An optical spectrometer is located remotely from the site. A second optical fiber is connected to the optical spectrometer at one end and the plasma source at the other end to carry the optical radiation from the plasma source to the spectrometer. 10 figs.

  15. Laser Ablation Inductively Coupled Plasma Mass Spectrometry

    PubMed Central

    Hutchinson, Robert W.; McLachlin, Katherine M.; Riquelme, Paloma; Haarer, Jan; Broichhausen, Christiane; Ritter, Uwe; Geissler, Edward K.; Hutchinson, James A.

    2015-01-01

    ABSTRACT New analytical techniques for multiparametric characterisation of individual cells are likely to reveal important information about the heterogeneity of immunological responses at the single-cell level. In this proof-of-principle study, laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) was applied to the problem of concurrently detecting 24 lineage and activation markers expressed by human leucocytes. This approach was sufficiently sensitive and specific to identify subpopulations of isolated T, B, and natural killer cells. Leucocyte subsets were also accurately detected within unfractionated peripheral blood mononuclear cells preparations. Accordingly, we judge LA-ICP-MS to be a suitable method for assessing expression of multiple tissue antigens in solid-phase biological specimens, such as tissue sections, cytospins, or cells grown on slides. These results augur well for future development of LA-ICP-MS–based bioimaging instruments for general users. PMID:27500232

  16. Laser ablation inductively coupled plasma mass spectrometry

    SciTech Connect

    Durrant, S.F.

    1996-07-01

    Laser ablation for solid sample introduction to inductively coupled plasma mass spectrometry for bulk and spatially-resolved elemental analysis is briefly reviewed. {copyright} {ital 1996 American Institute of Physics.}

  17. Antenna-coupled microwave kinetic inductance detectors

    NASA Astrophysics Data System (ADS)

    Day, P. K.; Leduc, H. G.; Goldin, A.; Vayonakis, T.; Mazin, B. A.; Kumar, S.; Gao, J.; Zmuidzinas, J.

    2006-04-01

    We report on the development of Microwave Kinetic Inductance Detectors (MKIDs) coupled to planar antennas for millimeter/submillimeter wavelengths. The MKID is a relatively new type of superconducting photon detector which is applicable from millimeter-wave frequencies to X-rays. Photons are absorbed in a superconductor, producing quasiparticle excitations, which change the surface reactance (kinetic inductance) of the superconductor. The changes in kinetic inductance are monitored using microwave high-Q thin-film superconducting resonators. Because the MKID is particularly amenable to frequency-domain multiplexing, with likely detector multiplexing factors of ˜103 or more per cryogenic amplifier, these detectors are well suited for use in large arrays. We have fabricated MKIDs coupled to submillimeter slot-array antennas using microstrip lines and have detected power from a thermal radiation source. We discuss the potential of antenna-coupled MKID arrays for ground and space-based millimeter/submillimeter imaging.

  18. Inductively coupled wireless RF coil arrays.

    PubMed

    Bulumulla, S B; Fiveland, E; Park, K J; Foo, T K; Hardy, C J

    2015-04-01

    As the number of coils increases in multi-channel MRI receiver-coil arrays, RF cables and connectors become increasingly bulky and heavy, degrading patient comfort and slowing workflow. Inductive coupling of signals provides an attractive "wireless" approach, with the potential to reduce coil weight and cost while simplifying patient setup. In this work, multi-channel inductively coupled anterior arrays were developed and characterized for 1.5T imaging. These comprised MR receiver coils inductively (or "wirelessly") linked to secondary or "sniffer" coils whose outputs were transmitted via preamps to the MR system cabinet. The induced currents in the imaging coils were blocked by passive diode circuits during RF transmit. The imaging arrays were totally passive, obviating the need to deliver power to the coils, and providing lightweight, untethered signal reception with easily positioned coils. Single-shot fast spin echo images were acquired from 5 volunteers using a 7-element inductively coupled coil array and a conventionally cabled 7-element coil array of identical geometry, with the inductively-coupled array showing a relative signal-to-noise ratio of 0.86 +/- 0.07. The concept was extended to a larger 9-element coil array to demonstrate the effect of coil element size on signal transfer and RF-transmit blocking. PMID:25523607

  19. Determination of 90Sr / 238U ratio by double isotope dilution inductively coupled plasma mass spectrometer with multiple collection in spent nuclear fuel samples with in situ 90Sr / 90Zr separation in a collision-reaction cell

    NASA Astrophysics Data System (ADS)

    Isnard, H.; Aubert, M.; Blanchet, P.; Brennetot, R.; Chartier, F.; Geertsen, V.; Manuguerra, F.

    2006-02-01

    Strontium-90 is one of the most important fission products generated in nuclear industry. In the research field concerning nuclear waste disposal in deep geological environment, it is necessary to quantify accurately and precisely its concentration (or the 90Sr / 238U atomic ratio) in irradiated fuels. To obtain accurate analysis of radioactive 90Sr, mass spectrometry associated with isotope dilution is the most appropriated method. But, in nuclear fuel samples the interference with 90Zr must be previously eliminated. An inductively coupled plasma mass spectrometer with multiple collection, equipped with an hexapole collision cell, has been used to eliminate the 90Sr / 90Zr interference by addition of oxygen in the collision cell as a reactant gas. Zr + ions are converted into ZrO +, whereas Sr + ions are not reactive. A mixed solution, prepared from a solution of enriched 84Sr and a solution of enriched 235U was then used to quantify the 90Sr / 238U ratio in spent fuel sample solutions using the double isotope dilution method. This paper shows the results, the reproducibility and the uncertainties that can be obtained with this method to quantify the 90Sr / 238U atomic ratio in an UOX (uranium oxide) and a MOX (mixed oxide) spent fuel samples using the collision cell of an inductively coupled plasma mass spectrometer with multiple collection to perform the 90Sr / 90Zr separation. A comparison with the results obtained by inductively coupled plasma mass spectrometer with multiple collection after a chemical separation of strontium from zirconium using a Sr spec resin (Eichrom) has been performed. Finally, to validate the analytical procedure developed, measurements of the same samples have been performed by thermal ionization mass spectrometry, used as an independent technique, after chemical separation of Sr.

  20. Induction coupled thermomagnetic processing: A disruptive technology

    DOE PAGESBeta

    Ahmad, Aquil; Mackiewicz-Ludtka, Gail; Pfaffmann, George; Ludtka, Gerard Michael

    2016-06-01

    Here, one of the major goals of the U.S. Department of Energy (DoE) is to achieve energy savings with a corresponding reduction in the carbon footprint. With this in mind, the DoE sponsored the Induction Coupled Thermomagnetic Processing (ITMP) project with major partners Eaton Corp., Ajax Tocco Magnethermic, and Oak Ridge National Laboratory (ORNL) to evaluate the viability of processing metals in a strong magnetic field.

  1. Induction and escalation therapies in multiple sclerosis.

    PubMed

    Fenu, G; Lorefice, L; Frau, F; Coghe, G C; Marrosu, M G; Cocco, E

    2015-01-01

    Multiple sclerosis (MS) is a chronic demyelinating disease affecting the central nervous system. Pharmacological therapy of MS includes symptomatic drugs, treatment for relapses (corticosteroid and intravenous immunoglobulin) and disease modifying drugs (DMDs) defined as pharmacological agents that have an impact on relapse rate, disability accumulation and radiological outcomes. Two different therapeutic approaches are widely used in MS: escalation and induction therapy. Escalation therapy consists of an early start with first line DMDs (beta interferon, glatiramer acetate, teriflunomide, dimethyl fumarate) and if DMDs are ineffective or partially effective, switching to second line drugs (mitoxantrone, natalizumab, fingolimod). Induction therapy consists of the early use of immunosuppressant drugs followed by long-term maintenance treatment, generally with immunomodulatory agents. While the use of natalizumab and fingolimod as first line drugs is indicated for aggressive forms of MS, the indication for mitoxantrone as an induction treatment arises from randomized studies demonstrating that induction therapy with mitoxantrone followed by DMD maintenance is more effective than monotherapy with beta interferon. However, the safety profile of induction drugs indicates this is not an acceptable therapeutic strategy for all MS patients in all phases of the disease. The upcoming challenge is to identify patients at high risk of disability development from their clinical characteristics, radiological findings or biomarkers. Furthermore, future studies to establish an individual safety profile stratification are needed. PMID:25938688

  2. Electrical Coupling Efficiency of Inductive Plasma Accelerators

    NASA Technical Reports Server (NTRS)

    Martin, Adam K.; Eskridge, Richard H.

    2005-01-01

    A single-stage pulsed inductive plasma accelerator is modeled as an inductive mass-driver. The plasma is treated as a rigid slug, which acts as the armature. The system is a transformer, with the drive coil serving as the primary and the slug as the secondary. We derive a set of coupled dynamic-circuit equations, which depend on five dimensionless coefficients, and on the functional form of the mutual inductance profile, M (z). For a given coil geometry, M (z) was determined experimentally and compared to the results of calculations carried out with QuickField. The equations are solved with various coefficient values, in order to determine the conditions that yield high efficiencies. It was found that the coupling efficiency can be quite high and likely scales with power, although this does not preclude operation at lower power with acceptable efficiency. The effect of an imbedded magnetic bias flux, as for the case of a plasmoid thruster, was also included in the calculations.

  3. Starter for inductively coupled plasma tube

    DOEpatents

    Hull, D.E.; Bieniewski, T.M.

    1988-08-23

    A starter assembly is provided for use with an inductively coupled plasma (ICP) tube to reliably initiate a plasma at internal pressures above about 30 microns. A conductive probe is inserted within the inductor coil about the tube and insulated from the tube shield assembly. A capacitive circuit is arranged for momentarily connecting a high voltage radio-frequency generator to the probe while simultaneously energizing the coil. When the plasma is initiated the probe is disconnected from the generator and electrically connected to the shield assembly for operation. 1 fig.

  4. Starter for inductively coupled plasma tube

    DOEpatents

    Hull, Donald E.; Bieniewski, Thomas M.

    1988-01-01

    A starter assembly is provided for use with an inductively coupled plasma (ICP) tube to reliably initate a plasma at internal pressures above about 30 microns. A conductive probe is inserted within the inductor coil about the tube and insulated from the tube shield assembly. A capacitive circuit is arranged for momentarily connecting a high voltage radio-frequency generator to the probe while simultaneously energizing the coil. When the plasma is initiated the probe is disconnected from the generator and electrically connected to the shield assembly for operation.

  5. Inductive coupled radio frequency plasma bridge neutralizer.

    PubMed

    Scholze, F; Tartz, M; Neumann, H

    2008-02-01

    A 13.56 MHz radio frequency plasma bridge neutralizer (rf-PBN) for ion thruster applications as well as ion beam surface processing of insulating materials is presented. The energy for the plasma excitation is inductively coupled into the plasma chamber. Because no components are located inside the plasma, the lifetime of the rf-PBN is expected to be very long. A compact tuning system adapts the input power to the plasma impedance. The electron current may be controlled over a wide range by the rf input power. An electron current of up to 1.6 A has been extracted. PMID:18315215

  6. Induction Charge Detector with Multiple Sensing Stages

    NASA Technical Reports Server (NTRS)

    Gamero-Castano, Manuel

    2008-01-01

    An induction charge detector with multiple sensing stages has been conceived for use in characterizing sprayed droplets, dust particles, large ionized molecules, and the like. Like related prior single-stage devices, each stage yields a measurement of the electric charge and the time of flight of the particle. In effect, an n-stage sensor yields n independent sets of such measurements from the same particle. The benefit of doing this is to increase the effective signal-to-noise ratio and thereby lower the charge-detection limit and the standard error of the charge measurement.

  7. Improving induction therapy in multiple myeloma.

    PubMed

    Nooka, Ajay; Gleason, Charise; Lonial, Sagar

    2010-07-01

    Significant improvements in induction therapy for multiple myeloma have been seen over the past decade for both transplant-eligible patients and transplant-ineligible patients. The emergence of novel agents in managing myeloma has revealed new directions for clinicians to approach the disease. The first determinant is transplant eligibility. With the recognition of the prognostic impact of postinduction response on overall outcomes, the importance of the choice of optimal regimen has become more important than ever. The preference of induction therapy for transplant-eligible patients has progressively changed from the alkylator-based therapies to doublet therapies to triplet therapies incorporating immunomodulatory drugs (IMiDs) and proteasome inhibitors. The role of quadruplet therapies remains unclear, but with appropriate dosage modifications, these regimens were efficacious and had an acceptable toxicity profile. Similar treatment approaches for transplant-ineligible patients resulted in superior outcomes with the triplet therapies. Many challenges remain however, such as achieving greater depth of responses with molecular remissions and more effective use of risk stratification in induction therapy. These are still to be explored. PMID:20449692

  8. Intelligent autonomous inductively coupled plasma instrumental operation

    NASA Astrophysics Data System (ADS)

    Webb, Douglas P.

    The development of a framework for the automated analysis of inductively couple plasma atomic emission spectroscopy is present. Some of the research that lead to current state of this framework is presented. A small expert system that uses information about the current sample to generate a line search strategy which minimizes the number of emission lines which need to be measured, and avoids spectral overlaps when possible. A program is presented that evaluates the minimum number of spectral windows required to perform elemental analysis by ICP- AES, given a certain spectral window width. A method with the potential for rapidly ascertaining the physical properties of the sample matrix is presented. This system has the potential to help reduce sample introduction related system failures. Finally, three optimization algorithms are compared in their ability to optimize ICP- AES performance, from this an optimization module was developed for inclusion in the automated analysis framework.

  9. Inductively coupled stent antennas in MRI.

    PubMed

    Quick, Harald H; Kuehl, Hilmar; Kaiser, Gernot; Bosk, Silke; Debatin, Jörg F; Ladd, Mark E

    2002-11-01

    The development of intimal hyperplasia following stent deployment can lead to narrowing or even occlusion of the stent lumen. The underlying mechanisms leading to neointimal proliferation within stents remain largely unknown. Long-term evaluation of stent patency requires a noninvasive means for assessing the stent lumen. MR angiography (MRA) has shown potential to provide noninvasive assessment of the vascular system. However, a detailed assessment of the stent lumen with MRI is often hampered by material-dependent susceptibility artifacts, as well as by radiofrequency (RF) eddy currents generated inside the electrically conducting stent mesh. In this study, stent prototypes were designed to act as active resonant structures at the Larmor frequency of the MR system. Employing the principle of inductive coupling, the B(1) fields of the stents were coupled to that of an outside surface coil. The stents thus acted as local RF signal amplifiers. Various stent designs were investigated regarding their coupling to an external coil, signal homogeneity, and suitability for mechanical expansion for implantation purposes. The dependency of flip angle amplification on the quality factor Q of the stents was systematically investigated. Phantom experiments revealed signal amplification in all stent prototypes. Signal enhancement inside and close to the surface of the stents enabled their localization with high contrast in MR images. In vivo imaging experiments in the iliac, renal, and splenic arteries of two pigs confirmed the in vitro findings. Wireless active visualization of stents allows for detailed analysis of the stent lumen with high contrast and spatial resolution. The proposed method could thus provide a powerful diagnostic means for the noninvasive long-term follow-up of stent patency, thereby enhancing our understanding of the mechanisms of restenosis. PMID:12417992

  10. Multiple beam induction linac research at LBL

    SciTech Connect

    Garvey, T.; Eylon, S.; Fessenden, T.J.; Hahn, K.; Henestroza, E.; Keefe, D.

    1990-06-01

    We present results of progress on the LBL multiple beam induction linac experiment (MBE-4). This machine models the accelerator physics of the electric-focused portion of a driver for heavy ion inertial confinement fusion. Four beams of cesium ions are accelerated in common through twenty four induction gaps while being separately focused in individual electrostatic AG focusing channels. Early experiments have demonstrated current amplification in the linac, from 10 mA to 90 mA per beam. This is achieved both by acceleration (from 200 keV to 1 MeV) and by carefully controlled bunch compression. Recent experiments have concentrated on studies of beams extracted from an ion source which produces 5 mA cesium beams at emittances near 0.03 {pi} mm-mrad (normalized). Experiments and theory show a growth of emittance (by about a factor of 2) as these beams are accelerated through the linac. Results of recent measurements of the transverse emittance behavior of these strongly space-charge-dominated ion beams are reviewed and compared with theory. 9 refs., 3 figs.

  11. THE DETERMINATION OF MERCURY AND MULTIPLE METALS IN DIETARY MATRICES USING DIRECT INJECTION NEBULIZATION INDUCTIVELY COUPLED PLASMA MASS SPECTROMETRY (DIN-ICP/MS)

    EPA Science Inventory

    Mercury (Hg) is a Persistent Bioaccumulative Toxin. Currently, low-level mercury (Hg) and low-level multiple-metals analyses require separate methods. Due to the high costs of performing both types of analyses, research planners often have to choose one or the other. For examp...

  12. Advantages of N2 and Ar as reaction gases for measurement of multiple Se isotopes using inductively coupled plasma-mass spectrometry with a collision/reaction cell

    NASA Astrophysics Data System (ADS)

    Olesik, John W.; Gray, Patrick J.

    2014-10-01

    Thirteen collision/reaction gases (CH4, O2, H2, CH3F, C2H6, N2O, NH3, SF6, Xe, Ne, N2, CO and Ar) were investigated to reduce the ArAr+, Ar2H+, Ar2H2+, SeH+, BrH+ and ArCl+ overlaps on Se+ isotopes. N2 and Ar had particular advantages for the measurement of multiple Se isotopes compared to the other gases. Experiments using CH4 and CD4 determined that H-atom transfer from CH4 to Se+ resulted in the formation of SeH+.

  13. Titanium oxidation by rf inductively coupled plasma

    NASA Astrophysics Data System (ADS)

    Valencia-Alvarado, R.; de la Piedad-Beneitez, A.; López-Callejas, R.; Barocio, S. R.; Mercado-Cabrera, A.; Peña-Eguiluz, R.; Muñoz-Castro, A. E.; Rodríguez-Méndez, B. G.; de la Rosa-Vázquez, J. M.

    2014-05-01

    The development of titanium dioxide (TiO2) films in the rutile and anatase phases is reported. The films have been obtained from an implantation/diffusion and sputtering process of commercially pure titanium targets, carried out in up to 500 W plasmas. The experimental outcome is of particular interest, in the case of anatase, for atmospheric pollution degradation by photocatalysis and, as to the rutile phase, for the production of biomaterials required by prosthesis and implants. The reactor employed consists in a cylindrical pyrex-like glass vessel inductively coupled to a 13.56 MHz RF source. The process takes place at a 5×10-2 mbar pressure with the target samples being biased from 0 to -3000 V DC. The anatase phase films were obtained from sputtering the titanium targets over glass and silicon electrically floated substrates placed 2 cm away from the target. The rutile phase was obtained by implantation/diffusion on targets at about 700 °C. The plasma was developed from a 4:1 argon/oxygen mixture for ~5 hour processing periods. The target temperature was controlled by means of the bias voltage and the plasma source power. The obtained anatase phases did not require annealing after the plasma oxidation process. The characterization of the film samples was conducted by means of x-ray diffraction, scanning electron microscopy, x-ray photoelectron spectroscopy and Raman spectroscopy.

  14. Method of processing materials using an inductively coupled plasma

    DOEpatents

    Hull, Donald E.; Bieniewski, Thomas M.

    1990-01-01

    A method for making fine power using an inductively coupled plasma. The method provides a gas-free environment, since the plasma is formed without using a gas. The starting material used in the method is in solid form.

  15. EVALUATION OF AN INDUCTIVELY COUPLED PLASMA, MULTICHANNEL SPECTROMETRIC ANALYSIS SYSTEM

    EPA Science Inventory

    An inductively coupled plasma, multielement atomic emission spectrometric analysis system has been evaluated with respect to the Environmental Protection Agency's need for a rapid method for determination of trace elemental concentrations in water. Data are presented on detection...

  16. Gold fingerprinting by laser ablation inductively coupled plasma mass spectrometry

    NASA Astrophysics Data System (ADS)

    Watling, R. John; Herbert, Hugh K.; Delev, Dianne; Abell, Ian D.

    1994-02-01

    Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) has been applied to the characterization of the trace element composition "fingerprint" of selected gold samples from Western Australia and South Africa. By comparison of the elemental associations it is possible to relate gold to a specific mineralizing event, mine or bullion sample. This methodology facilitates identification of the provenance of stolen gold or gold used in salting activities. In this latter case, it is common for gold from a number of sources to be used in the salting process. Consequently, gold in the prospect being salted will not come from a single source and identification of multiple sources for this gold will establish that salting has occurred. Preliminary results also indicate that specific elemental associations could be used to identify the country of origin of gold. The technique has already been applied in 17 cases involving gold theft in Western Australia, where it is estimated that up to 2% of gold production is "relocated" each year as a result of criminal activities.

  17. Method of processing materials using an inductively coupled plasma

    DOEpatents

    Hull, Donald E.; Bieniewski, Thomas M.

    1989-01-01

    A method for coating surfaces or implanting ions in an object using an inductively coupled plasma. The method provides a gas-free environment, since the plasma is formed without using a gas. The coating material or implantation material is intitially in solid form.

  18. Superposition of Inductive and Capacitive Coupling in Superconducting LC Resonators

    NASA Astrophysics Data System (ADS)

    Gladchenko, Sergiy; Khalil, Moe; Lobb, C. J.; Wellstood, F. C.; Osborn, Kevin D.

    2011-06-01

    We present an experimental investigation of lumped-element superconducting LC resonators designed to provide different types of coupling to a transmission line. We have designed four resonator geometries including dipole and quadrupole configured inductors connected in parallel with low loss SiNx dielectric parallel-plate capacitors. The design of the resonator allows a small change in the symmetry of the inductor or grounding of the capacitor to allow LC resonators with: 1) inductive coupling, 2) capacitive coupling, 3) both types of coupling, or 4) greatly reduced coupling. We measured all four designs at a temperature of 30mK at different values of power. We compare the extracted data from the four resonator types and find that both capacitive and inductive coupling can be included and that when left off, only a minor change in the circuit design is necessary. We also find a variation in the measured loss tangent of less than a few percent, which is a test of the systematic precision of the measurement technique.

  19. Ion-wave stabilization of an inductively coupled plasma

    SciTech Connect

    Camparo, J.C.; Mackay, R.

    2006-04-24

    Stabilization of the rf power driving an inductively coupled plasma (ICP) has implications for fields ranging from atomic clocks to analytical chemistry to illumination technology. Here, we demonstrate a technique in which the plasma itself acts as a probe of radio wave power, and provides a correction signal for active rf-power control. Our technique takes advantage of the resonant nature of forced ion waves in the plasma, and their observation in the ICP's optical emission.

  20. Volumetric loss quantification using ultrasonic inductively coupled transducers

    NASA Astrophysics Data System (ADS)

    Gong, Peng; Hay, Thomas R.; Greve, David W.; Oppenheim, Irving J.

    2015-03-01

    The pulse-echo method is widely used for plate and pipe thickness measurement. However, the pulse echo method does not work well for detecting localized volumetric loss in thick-wall tubes, as created by erosion damage, when the morphology of volumetric loss is irregular and can reflect ultrasonic pulses away from the transducer, making it difficult to detect an echo. In this paper, we propose a novel method using an inductively coupled transducer to generate longitudinal waves propagating in a thick-wall aluminum tube for the volumetric loss quantification. In the experiment, longitudinal waves exhibit diffraction effects during the propagation which can be explained by the Huygens-Fresnel principle. The diffractive waves are also shown to be significantly delayed by the machined volumetric loss on the inside surface of the thick-wall aluminum tube. It is also shown that the inductively coupled transducers can generate and receive similar ultrasonic waves to those from wired transducers, and the inductively coupled transducers perform as well as the wired transducers in the volumetric loss quantification when other conditions are the same.

  1. Optimizing plasmonic nanoantennas via coordinated multiple coupling

    PubMed Central

    Lin, Linhan; Zheng, Yuebing

    2015-01-01

    Plasmonic nanoantennas, which can efficiently convert light from free space into sub-wavelength scale with the local field enhancement, are fundamental building blocks for nanophotonic systems. Predominant design methods, which exploit a single type of near- or far-field coupling in pairs or arrays of plasmonic nanostructures, have limited the tunability of spectral response and the local field enhancement. To overcome this limit, we are developing a general strategy towards exploiting the coordinated effects of multiple coupling. Using Au bowtie nanoantenna arrays with metal-insulator-metal configuration as examples, we numerically demonstrate that coordinated design and implementation of various optical coupling effects leads to both the increased tunability in the spectral response and the significantly enhanced electromagnetic field. Furthermore, we design and analyze a refractive index sensor with an ultra-high figure-of-merit (254), a high signal-to-noise ratio and a wide working range of refractive indices, and a narrow-band near-infrared plasmonic absorber with 100% absorption efficiency, high quality factor of up to 114 and a wide range of tunable wavelength from 800 nm to 1,500 nm. The plasmonic nanoantennas that exploit coordinated multiple coupling will benefit a broad range of applications, including label-free bio-chemical detection, reflective filter, optical trapping, hot-electron generation, and heat-assisted magnetic recording. PMID:26423015

  2. Optimizing plasmonic nanoantennas via coordinated multiple coupling

    NASA Astrophysics Data System (ADS)

    Lin, Linhan; Zheng, Yuebing

    2015-10-01

    Plasmonic nanoantennas, which can efficiently convert light from free space into sub-wavelength scale with the local field enhancement, are fundamental building blocks for nanophotonic systems. Predominant design methods, which exploit a single type of near- or far-field coupling in pairs or arrays of plasmonic nanostructures, have limited the tunability of spectral response and the local field enhancement. To overcome this limit, we are developing a general strategy towards exploiting the coordinated effects of multiple coupling. Using Au bowtie nanoantenna arrays with metal-insulator-metal configuration as examples, we numerically demonstrate that coordinated design and implementation of various optical coupling effects leads to both the increased tunability in the spectral response and the significantly enhanced electromagnetic field. Furthermore, we design and analyze a refractive index sensor with an ultra-high figure-of-merit (254), a high signal-to-noise ratio and a wide working range of refractive indices, and a narrow-band near-infrared plasmonic absorber with 100% absorption efficiency, high quality factor of up to 114 and a wide range of tunable wavelength from 800 nm to 1,500 nm. The plasmonic nanoantennas that exploit coordinated multiple coupling will benefit a broad range of applications, including label-free bio-chemical detection, reflective filter, optical trapping, hot-electron generation, and heat-assisted magnetic recording.

  3. Optimizing plasmonic nanoantennas via coordinated multiple coupling.

    PubMed

    Lin, Linhan; Zheng, Yuebing

    2015-01-01

    Plasmonic nanoantennas, which can efficiently convert light from free space into sub-wavelength scale with the local field enhancement, are fundamental building blocks for nanophotonic systems. Predominant design methods, which exploit a single type of near- or far-field coupling in pairs or arrays of plasmonic nanostructures, have limited the tunability of spectral response and the local field enhancement. To overcome this limit, we are developing a general strategy towards exploiting the coordinated effects of multiple coupling. Using Au bowtie nanoantenna arrays with metal-insulator-metal configuration as examples, we numerically demonstrate that coordinated design and implementation of various optical coupling effects leads to both the increased tunability in the spectral response and the significantly enhanced electromagnetic field. Furthermore, we design and analyze a refractive index sensor with an ultra-high figure-of-merit (254), a high signal-to-noise ratio and a wide working range of refractive indices, and a narrow-band near-infrared plasmonic absorber with 100% absorption efficiency, high quality factor of up to 114 and a wide range of tunable wavelength from 800 nm to 1,500 nm. The plasmonic nanoantennas that exploit coordinated multiple coupling will benefit a broad range of applications, including label-free bio-chemical detection, reflective filter, optical trapping, hot-electron generation, and heat-assisted magnetic recording. PMID:26423015

  4. Impact of Gas Heating in Inductively Coupled Plasmas

    NASA Technical Reports Server (NTRS)

    Hash, D. B.; Bose, D.; Rao, M. V. V. S.; Cruden, B. A.; Meyyappan, M.; Sharma, S. P.; Biegel, Bryan (Technical Monitor)

    2001-01-01

    Recently it has been recognized that the neutral gas in inductively coupled plasma reactors heats up significantly during processing. The resulting gas density variations across the reactor affect reaction rates, radical densities, plasma characteristics, and uniformity within the reactor. A self-consistent model that couples the plasma generation and transport to the gas flow and heating has been developed and used to study CF4 discharges. A Langmuir probe has been used to measure radial profiles of electron density and temperature. The model predictions agree well with the experimental results. As a result of these comparisons along with the poorer performance of the model without the gas-plasma coupling, the importance of gas heating in plasma processing has been verified.

  5. Investigation of inductively coupled ultrasonic transducer system for NDE.

    PubMed

    Zhong, Cheng Huan; Croxford, Anthony J; Wilcox, Paul D

    2013-06-01

    Inductive coupling offers a simple solution to wirelessly probe ultrasonic transducers. This paper investigates the theory and feasibility of such an inductively coupled transducer system in the context of nondestructive evaluation (NDE) applications. The noncontact interface is based on electromagnetic coupling between three coils; one of the coils is physically connected to the transducer, the other two are in a separate probing unit, where they are connected to the transmit and receive channels of the instrumentation. The complete system is modeled as a three-port network with the measured impedance of a bonded piezoelectric ceramic disc representing a sensor attached to an arbitrary solid substrate. The developed transmission line model is a function of the physical parameters of the electromagnetic system, such as the number of turns and diameter of each coil, and their separation. This model provides immediate predictions of electrical input impedance and pulse-echo response. The model has been validated experimentally and a sensitivity analysis of the input parameters performed. This has enabled optimization of the various parameters. Inductively coupled transducer systems have been built for both bulk and guided wave examples. By using chirped excitation and baseline subtraction, inspection distance of up to 700 mm is achieved in single-shot, guided-wave pulse-echo mode measurements with a 5 mm separation between the probing coils and transducer coil on an aluminum plate structure. In the bulk wave example, a delamination in an 8.9-mm-thick carbon fiber composite specimen is successfully identified from the changes in the arrival time of a reflected pulse. PMID:25004474

  6. Multiple-Coil, Pulse-Induction Metal Detector

    NASA Technical Reports Server (NTRS)

    Lesky, Edward S.; Reid, Alan M.; Bushong, Wilton E.; Dickey, Duane P.

    1988-01-01

    Multiple-head, pulse-induction metal detector scans area of 72 feet squared with combination of eight detector heads, each 3 ft. square. Head includes large primary coil inducing current in smaller secondary coils. Array of eight heads enables searcher to cover large area quickly. Pulses applied to primary coil, induced in secondary coils measured to determine whether metal present within range of detector head. Detector designed for recovery of Space Shuttle debris.

  7. CAPILLARY ELECTROPHORESIS COUPLED ON-LINE WITH INDUCTIVELY COUPLED PLASMA MASS SPECTROMETRY FOR ELEMENTAL SPECIATION

    EPA Science Inventory

    A novel interface to connect a capillary electrophoresis (CE) system with an inductively coupled plasma mass spectrometric (ICPMS) detector is reported here. The interface was built using a direct injection nebulizer (DIN) system. In this interface, the CE capillary was placed co...

  8. Inductively coupled plasma etching of GaN

    SciTech Connect

    Shul, R.J.; McClellan, G.B.; Casalnuovo, S.A.; Rieger, D.J.; Pearton, S.J.; Constantine, C.; Barratt, C.; Karlicek, R.F. Jr.; Tran, C.; Schurman, M.

    1996-08-01

    Inductively coupled plasma (ICP) etch rates for GaN are reported as a function of plasma pressure, plasma chemistry, rf power, and ICP power. Using a Cl{sub 2}/H{sub 2}/Ar plasma chemistry, GaN etch rates as high as 6875 A/min are reported. The GaN surface morphology remains smooth over a wide range of plasma conditions as quantified using atomic force microscopy. Several etch conditions yield highly anisotropic profiles with smooth sidewalls. These results have direct application to the fabrication of group-III nitride etched laser facets. {copyright} {ital 1996 American Institute of Physics.}

  9. Ion deposition by inductively coupled plasma mass spectrometry

    SciTech Connect

    Hu, K.; Houk, R.S.

    1996-03-01

    An atmospheric pressure inductively coupled plasma (ICP) is used with a quadrupole mass spectrometer (MS) for ion deposition. The deposited element is introduced as a nebulized aqueous solution. Modifications to the ICP-MS device allow generation and deposition of a mass-resolved beam of {sup 165}Ho{sup +} at 5{times}10{sup 12} ions s{sup {minus}1}. The ICP is a universal, multielement ion source that can potentially be used for applications such as deposition of mixtures of widely varying stoichiometry or of alternating layers of different elements. {copyright} {ital 1996 American Vacuum Society}

  10. Positive moment of an inductively coupled Josephson-junction array

    SciTech Connect

    Chandran, M.

    1997-09-01

    We present the results of a Langevin dynamic simulation of an inductively coupled Josephson-junction array in the absence of {pi} junctions. The magnetic susceptibility (4{pi}{chi}) under field-cooled conditions becomes positive in certain range of applied field (f) in antithesis to the Meissner effect, whereas the zero-field cooled susceptibility is negative for all values of f. The results are discussed in the light of recent experiments showing a paramagnetic Meissner effect in certain granular superconductors. {copyright} {ital 1997} {ital The American Physical Society}

  11. Method of processing materials using an inductively coupled plasma

    DOEpatents

    Hull, D.E.; Bieniewski, T.M.

    1987-04-13

    A method of processing materials. The invention enables ultrafine, ultrapure powders to be formed from solid ingots in a gas free environment. A plasma is formed directly from an ingot which insures purity. The vaporized material is expanded through a nozzle and the resultant powder settles on a cold surface. An inductively coupled plasma may also be used to process waste chemicals. Noxious chemicals are directed through a series of plasma tubes, breaking molecular bonds and resulting in relatively harmless atomic constituents. 3 figs.

  12. Fission Yield Measurements by Inductively Coupled Plasma Mass-Spectrometry

    SciTech Connect

    Irina Glagolenko; Bruce Hilton; Jeffrey Giglio; Daniel Cummings; Karl Grimm; Richard McKnight

    2009-11-01

    Correct prediction of the fission products inventory in irradiated nuclear fuels is essential for accurate estimation of fuel burnup, establishing proper requirements for spent fuel transportation and storage, materials accountability and nuclear forensics. Such prediction is impossible without accurate knowledge of neutron induced fission yields. Unfortunately, the accuracy of the fission yields reported in the ENDF/B-VII.0 library is not uniform across all of the data and much of the improvement is desired for certain isotopes and fission products. We discuss our measurements of cumulative fission yields in nuclear fuels irradiated in thermal and fast reactor spectra using Inductively Coupled Plasma Mass Spectrometry.

  13. Inductively coupled plasma torch with laminar flow cooling

    DOEpatents

    Rayson, Gary D.; Shen, Yang

    1991-04-30

    An improved inductively coupled gas plasma torch. The torch includes inner and outer quartz sleeves and tubular insert snugly fitted between the sleeves. The insert includes outwardly opening longitudinal channels. Gas flowing through the channels of the insert emerges in a laminar flow along the inside surface of the outer sleeve, in the zone of plasma heating. The laminar flow cools the outer sleeve and enables the torch to operate at lower electrical power and gas consumption levels additionally, the laminar flow reduces noise levels in spectroscopic measurements of the gaseous plasma.

  14. Thin film coating process using an inductively coupled plasma

    DOEpatents

    Kniseley, Richard N.; Schmidt, Frederick A.; Merkle, Brian D.

    1990-01-30

    Thin coatings of normally solid materials are applied to target substrates using an inductively coupled plasma. Particles of the coating material are vaporized by plasma heating, and pass through an orifice to a first vacuum zone in which the particles are accelerated to a velocity greater than Mach 1. The shock wave generated in the first vacuum zone is intercepted by the tip of a skimmer cone that provides a second orifice. The particles pass through the second orifice into a second zone maintained at a higher vacuum and impinge on the target to form the coating. Ultrapure coatings can be formed.

  15. Inductive-dynamic magnetosphere-ionosphere coupling via MHD waves

    NASA Astrophysics Data System (ADS)

    Tu, Jiannan; Song, Paul; Vasyliūnas, Vytenis M.

    2014-01-01

    In the present study, we investigate magnetosphere-ionosphere/thermosphere (M-IT) coupling via MHD waves by numerically solving time-dependent continuity, momentum, and energy equations for ions and neutrals, together with Maxwell's equations (Ampère's and Faraday's laws) and with photochemistry included. This inductive-dynamic approach we use is fundamentally different from those in previous magnetosphere-ionosphere (M-I) coupling models: all MHD wave modes are retained, and energy and momentum exchange between waves and plasma are incorporated into the governing equations, allowing a self-consistent examination of dynamic M-I coupling. Simulations, using an implicit numerical scheme, of the 1-D ionosphere/thermosphere system responding to an imposed convection velocity at the top boundary are presented to show how magnetosphere and ionosphere are coupled through Alfvén waves during the transient stage when the IT system changes from one quasi steady state to another. Wave reflection from the low-altitude ionosphere plays an essential role, causing overshoots and oscillations of ionospheric perturbations, and the dynamical Hall effect is an inherent aspect of the M-I coupling. The simulations demonstrate that the ionosphere/thermosphere responds to magnetospheric driving forces as a damped oscillator.

  16. Microwave Kinetic Inductance Detector with Selective Polarization Coupling

    NASA Technical Reports Server (NTRS)

    Wollack, Edward; U-yen, Kongpop; Stevenson, Thomas; Brown, Ari; Moseley, Samuel; Hsieh, Wen-Ting

    2013-01-01

    A conventional low-noise detector requires a technique to both absorb incident power and convert it to an electrical signal at cryogenic temperatures. This innovation combines low-noise detector and readout functionality into one device while maintaining high absorption, controlled polarization sensitivity, and broadband detection capability. The resulting far-infrared detectors can be read out with a simple approach, which is compact and minimizes thermal loading. The proposed microwave kinetic inductance detector (MKID) consists of three basic elements. The first is the absorptive section in which the incident power is coupled to a superconducting resonator at far-infrared frequency above its superconducting critical frequency (where superconductor becomes normal conductor). This absorber's shape effectively absorbs signals in the desired polarization state and is resonant at the radio frequency (RF) used for readout of the device. Control over the metal film used in the absorber allows realization of structures with either a 50% broadband or 100% resonance absorptance over a 30% fractional bandwidth. The second element is a microwave resonator - which is realized from the thin metal films used to make the absorber as transmission lines - whose resonance frequency changes due to a variation in its kinetic inductance. The resonator's kinetic inductance is a function of the power absorbed by the device. A low-loss dielectric (mono-crystalline silicon) is used in a parallel-plate transmission line structure to realize the desired superconducting resonators. There is negligible coupling among the adjacent elements used to define the polarization sensitivity of each detector. The final component of the device is a microwave transmission line, which is coupled to the resonator, and allows detection of changes in resonance frequency for each detector in the focal plane array. The spiral shape of the detector's absorber allows incident power with two polarizations to

  17. Electron energy distributions in a magnetized inductively coupled plasma

    SciTech Connect

    Song, Sang-Heon E-mail: Sang-Heon.Song@us.tel.com; Yang, Yang; Kushner, Mark J.

    2014-09-15

    Optimizing and controlling electron energy distributions (EEDs) is a continuing goal in plasma materials processing as EEDs determine the rate coefficients for electron impact processes. There are many strategies to customize EEDs in low pressure inductively coupled plasmas (ICPs), for example, pulsing and choice of frequency, to produce the desired plasma properties. Recent experiments have shown that EEDs in low pressure ICPs can be manipulated through the use of static magnetic fields of sufficient magnitudes to magnetize the electrons and confine them to the electromagnetic skin depth. The EED is then a function of the local magnetic field as opposed to having non-local properties in the absence of the magnetic field. In this paper, EEDs in a magnetized inductively coupled plasma (mICP) sustained in Ar are discussed with results from a two-dimensional plasma hydrodynamics model. Results are compared with experimental measurements. We found that the character of the EED transitions from non-local to local with application of the static magnetic field. The reduction in cross-field mobility increases local electron heating in the skin depth and decreases the transport of these hot electrons to larger radii. The tail of the EED is therefore enhanced in the skin depth and depressed at large radii. Plasmas densities are non-monotonic with increasing pressure with the external magnetic field due to transitions between local and non-local kinetics.

  18. Negative ion density in inductively coupled chlorine plasmas

    SciTech Connect

    Hebner, G.A.

    1995-12-31

    The negative ion density in radio-frequency (rf) inductively-coupled chlorine discharges has been inferred using laser photodetachment spectroscopy. A Gaseous Electronics Conference (GEC) rf Reference Cell with an inductively coupled plasma source was used to produce the plasma. For this experiment, the chlorine pressure was between 20 and 50 mTorr and the rf power into the plasma was 150 to 250 Watts at 13.56 MHz. Light from a frequency quadrupled Nd:YAG laser (266 nm) was used to photodetach electrons from Cl{sup {minus}}. The time dependent excess electron density was then detected by a microwave interferometer operating at 80 GHz. Based upon the cross section for photodetachment and the measurement geometry, negative ion densities can be calculated. The inferred negative ion densities are at least an order of magnitude higher than the steady state electron density over the parameter space investigated. The dependence of the negative ion density on rf power, gas pressure, flow rate and rf phase will be discussed.

  19. Hybridized/coupled multiple resonances in nacre

    NASA Astrophysics Data System (ADS)

    Choi, Seung Ho; Kim, Young L.

    2014-01-01

    We report that nacre (also known as mother-of-pearl), a wondrous nanocomposite found in nature, is a rich photonic nanomaterial allowing the experimental realization of collective excitation and light amplification via coupled states. Localized modes in three-dimensional complex media are typically isolated in frequency and space. However, multiple local resonances can be hybridized in multilayered nanostructures of nacre so that the effective cavity size for efficient disordered resonators is scaled up. Localized modes in hybridized states in nacre are overlapped in frequency with similar shapes in space, thus being collectively excited and synergistically amplified. These hybridized states boost light amplification, leading to stable and regular multimode lasing at low excitation energy. The simplicity of ameliorating disordered resonators by mimicking nacre can further serve as platforms for developing cost-effective photonic systems and provide materials for fundamental research on complex media.

  20. Low-pressure water-cooled inductively coupled plasma torch

    DOEpatents

    Seliskar, Carl J.; Warner, David K.

    1988-12-27

    An inductively coupled plasma torch is provided which comprises an inner tube, including a sample injection port to which the sample to be tested is supplied and comprising an enlarged central portion in which the plasma flame is confined; an outer tube surrounding the inner tube and containing water therein for cooling the inner tube, the outer tube including a water inlet port to which water is supplied and a water outlet port spaced from the water inlet port and from which water is removed after flowing through the outer tube; and an r.f. induction coil for inducing the plasma in the gas passing into the tube through the sample injection port. The sample injection port comprises a capillary tube including a reduced diameter orifice, projecting into the lower end of the inner tube. The water inlet is located at the lower end of the outer tube and the r.f. heating coil is disposed around the outer tube above and adjacent to the water inlet.

  1. Low-pressure water-cooled inductively coupled plasma torch

    DOEpatents

    Seliskar, C.J.; Warner, D.K.

    1984-02-16

    An inductively coupled plasma torch is provided which comprises an inner tube, including a sample injection port to which the sample to be tested is supplied and comprising an enlarged central portion in which the plasma flame is confined; an outer tube surrounding the inner tube and containing water therein for cooling the inner tube, the outer tube including a water inlet port to which water is supplied and a water outlet port spaced from the water inlet port and from which water is removed after flowing through the outer tube; and an rf induction coil for inducing the plasma in the gas passing into the tube through the sample injection port. The sample injection port comprises a capillary tube including a reduced diameter orifice, projecting into the lower end of the inner tube. The water inlet is located at the lower end of the outer tube and the rf heating coil is disposed around the outer tube above and adjacent to the water inlet.

  2. Monitoring microbial metabolites using an inductively coupled resonance circuit

    PubMed Central

    Karnaushenko, Daniil; Baraban, Larysa; Ye, Dan; Uguz, Ilke; Mendes, Rafael G.; Rümmeli, Mark H.; de Visser, J. Arjan G. M.; Schmidt, Oliver G.; Cuniberti, Gianaurelio; Makarov, Denys

    2015-01-01

    We present a new approach to monitor microbial population dynamics in emulsion droplets via changes in metabolite composition, using an inductively coupled LC resonance circuit. The signal measured by such resonance detector provides information on the magnetic field interaction with the bacterial culture, which is complementary to the information accessible by other detection means, based on electric field interaction, i.e. capacitive or resistive, as well as optical techniques. Several charge-related factors, including pH and ammonia concentrations, were identified as possible contributors to the characteristic of resonance detector profile. The setup enables probing the ionic byproducts of microbial metabolic activity at later stages of cell growth, where conventional optical detection methods have no discriminating power. PMID:26264183

  3. An assessment of inductive coupling roadway powered vehicles

    NASA Technical Reports Server (NTRS)

    Leschly, K. O.; Feinberg, A.; Heft, R.; Warren, G.

    1980-01-01

    The technical concept underlying the roadway powered vehicle system is the combination of an electrical power source embedded in the roadway and a vehicle-mounted power pickup that is inductively coupled to the roadway power source. The feasibility of such a system, implemented on a large scale was investigated. Factors considered included current and potential transportation modes and requirements, economics, energy, technology, social and institutional issues. These factors interrelate in highly complex ways, and a firm understanding of each of them does not yet exist. The study therefore was structured to manipulate known data in equally complex ways to produce a schema of options and useful questions that can form a basis for further, harder research. A dialectical inquiry technique was used in which two adversary teams, mediated by a third-party team, debated each factor and its interrelationship with the whole of the known information on the topic.

  4. Transition of electron kinetics in weakly magnetized inductively coupled plasmas

    SciTech Connect

    Kim, Jin-Yong; Lee, Hyo-Chang; Kim, Young-Do; Chung, Chin-Wook; Kim, Young-Cheol

    2013-10-15

    Transition of the electron kinetics from nonlocal to local regime was studied in weakly magnetized solenoidal inductively coupled plasma from the measurement of the electron energy probability function (EEPF). Without DC magnetic field, the discharge property was governed by nonlocal electron kinetics at low gas pressure. The electron temperatures were almost same in radial position, and the EEPFs in total electron energy scale were radially coincided. However, when the DC magnetic field was applied, radial non-coincidence of the EEPFs in total electron energy scale was observed. The electrons were cooled at the discharge center where the electron heating is absent, while the electron temperature was rarely changed at the discharge boundary with the magnetic field. These changes show the transition from nonlocal to local electron kinetics and the transition is occurred when the electron gyration diameter was smaller than the skin depth. The nonlocal to local transition point almost coincided with the calculation results by using nonlocal parameter and collision parameter.

  5. Inductively Coupled Plasma Mass Spectrometry Uranium Error Propagation

    SciTech Connect

    Hickman, D P; Maclean, S; Shepley, D; Shaw, R K

    2001-07-01

    The Hazards Control Department at Lawrence Livermore National Laboratory (LLNL) uses Inductively Coupled Plasma Mass Spectrometer (ICP/MS) technology to analyze uranium in urine. The ICP/MS used by the Hazards Control Department is a Perkin-Elmer Elan 6000 ICP/MS. The Department of Energy Laboratory Accreditation Program requires that the total error be assessed for bioassay measurements. A previous evaluation of the errors associated with the ICP/MS measurement of uranium demonstrated a {+-} 9.6% error in the range of 0.01 to 0.02 {micro}g/l. However, the propagation of total error for concentrations above and below this level have heretofore been undetermined. This document is an evaluation of the errors associated with the current LLNL ICP/MS method for a more expanded range of uranium concentrations.

  6. Line-type inductively coupled plasma source with ferromagnetic module

    NASA Astrophysics Data System (ADS)

    Hyeuk Lim, Jong; Kim, Kyong Nam; Gweon, Gwang Ho; Yeom, Geun Young

    2009-01-01

    The characteristics of a line-type, internal antenna for an inductively coupled plasma (ICP) source installed with a ferromagnetic module were investigated for possible application to roll-to-roll processing of next-generation display devices. The use of 2 MHz instead of 13.56 MHz for the 2300 mm long ICP source improved the plasma uniformity to less than 11% along the antenna line. In addition, the use of Ni-Zn ferromagnetic material in the line-type antenna improved the plasma density to about 3.1 × 1011 cm-3 at 3500 W of 2 MHz radio frequency power by confining the induced, time-varying magnetic field between the antenna line and the substrate. When the photoresist-covered glass substrate was etched at 4000 W using 40 mTorr and Ar/O2 (7 : 3), an etch uniformity of about 5-6% was obtained along the antenna line.

  7. Monitoring microbial metabolites using an inductively coupled resonance circuit

    NASA Astrophysics Data System (ADS)

    Karnaushenko, Daniil; Baraban, Larysa; Ye, Dan; Uguz, Ilke; Mendes, Rafael G.; Rümmeli, Mark H.; de Visser, J. Arjan G. M.; Schmidt, Oliver G.; Cuniberti, Gianaurelio; Makarov, Denys

    2015-08-01

    We present a new approach to monitor microbial population dynamics in emulsion droplets via changes in metabolite composition, using an inductively coupled LC resonance circuit. The signal measured by such resonance detector provides information on the magnetic field interaction with the bacterial culture, which is complementary to the information accessible by other detection means, based on electric field interaction, i.e. capacitive or resistive, as well as optical techniques. Several charge-related factors, including pH and ammonia concentrations, were identified as possible contributors to the characteristic of resonance detector profile. The setup enables probing the ionic byproducts of microbial metabolic activity at later stages of cell growth, where conventional optical detection methods have no discriminating power.

  8. Exchange-coupled magnetic nanoparticles for efficient heat induction

    NASA Astrophysics Data System (ADS)

    Lee, Jae-Hyun; Jang, Jung-Tak; Choi, Jin-Sil; Moon, Seung Ho; Noh, Seung-Hyun; Kim, Ji-Wook; Kim, Jin-Gyu; Kim, Il-Sun; Park, Kook In; Cheon, Jinwoo

    2011-07-01

    The conversion of electromagnetic energy into heat by nanoparticles has the potential to be a powerful, non-invasive technique for biotechnology applications such as drug release, disease treatment and remote control of single cell functions, but poor conversion efficiencies have hindered practical applications so far. In this Letter, we demonstrate a significant increase in the efficiency of magnetic thermal induction by nanoparticles. We take advantage of the exchange coupling between a magnetically hard core and magnetically soft shell to tune the magnetic properties of the nanoparticle and maximize the specific loss power, which is a gauge of the conversion efficiency. The optimized core-shell magnetic nanoparticles have specific loss power values that are an order of magnitude larger than conventional iron-oxide nanoparticles. We also perform an antitumour study in mice, and find that the therapeutic efficacy of these nanoparticles is superior to that of a common anticancer drug.

  9. Experimental Study of Instabilities in Inductively-Coupled Electronegative Discharges

    NASA Astrophysics Data System (ADS)

    Leou, K. C.; Chen, G. S.

    2001-10-01

    The experimental investigation of oscillation type instabilities occuring in an inductively-coupled plasma of electronegative gases, Cl2 and O2 have been conducted. An impedance meter which is capable of measuring dynamic variations of plasma's RF impedance up to 20 kHz has been developed. An existing 36 GHz heterodyne interferometer, for measurement of line-averaged plasma density and a PMT, for measurement of plasma optical emissions, were also employed. Experiments were conducted in an etch reactor which employs an inductively coupled plasma. The reactor chamber has a diameter of 500 mm and a height of 200 mm. During the experiment, a blank wafer was placed on the electrostatic chuck to protect the chuck surface. Instabilities were observed as the RF match deviated from the perfect match point. In electronegative discharges, oscillation type instabilities occured with frequency around 1-10 kHz, which is consistent with the predition given by the charges balance model[1]. In Cl2 dicharges, however, the instabilities were also imposed by an envelop type modulation of frequency 10-100 Hz. From the relative intensity of the optical emissions, one can identify instabilities in three different modes: E mode, H mode and transition between E/H modes. In electropositive plasmas such as Ar, the high frequency type instability was not observed but a very low freqnency, around 10-100 Hz, oscillation occured. Preliminary studies suggested that this low frequency oscillation may be caused by oscillation in RF circuit. This is because, during this low frequency oscillations, the RF current measured by the impedance meter reaches minimum when the RF voltage peaks. Detailed experiemental results will be presented. References: [1] M.A. Lieberman, A.J. Lichtenberg,and A.M. Marakhtanov, Appl. Phys. Lett., V.75(23),PP.3617-3619(1999).

  10. Matrix effects in inductively coupled plasma mass spectrometry

    SciTech Connect

    Chen, Xiaoshan

    1995-07-07

    The inductively coupled plasma is an electrodeless discharge in a gas (usually Ar) at atmospheric pressure. Radio frequency energy generated by a RF power source is inductively coupled to the plasma gas through a water cooled load coil. In ICP-MS the {open_quotes}Fassel{close_quotes} TAX quartz torch commonly used in emission is mounted horizontally. The sample aerosol is introduced into the central flow, where the gas kinetic temperature is about 5000 K. The aerosol is vaporized, atomized, excited and ionized in the plasma, and the ions are subsequently extracted through two metal apertures (sampler and skimmer) into the mass spectrometer. In ICP-MS, the matrix effects, or non-spectroscopic interferences, can be defined as the type of interferences caused by dissolved concomitant salt ions in the solution. Matrix effects can be divided into two categories: (1) signal drift due to the deposition of solids on the sampling apertures; and/or (2) signal suppression or enhancement by the presence of the dissolved salts. The first category is now reasonably understood. The dissolved salts, especially refractory oxides, tend to deposit on the cool tip of the sampling cone. The clogging of the orifices reduces the ion flow into the ICP-MS, lowers the pressure in the first stage of ICP-MS, and enhances the level of metal oxide ions. Because the extent of the clogging increases with the time, the signal drifts down. Even at the very early stage of the development of ICP-MS, matrix effects had been observed. Houk et al. found out that the ICP-MS was not tolerant to solutions containing significant amounts of dissolved solids.

  11. Hypnoanalgesia for chronic pain: the response to multiple inductions at one session and to separate single inductions.

    PubMed Central

    Lewis, D O

    1992-01-01

    Serial hypnotic inductions conveying the same analgesic message produce a progressively longer response in an increasing number of patients. The resulting analgesia appears to be independent of the spacing of inductions--whether given at a single session or on separate occasions--and to depend upon their number. However, multiple inductions at a single session save time. Elimination of pain can be achieved, by either approach, for a year or more in up to 70% of patients. PMID:1433041

  12. Inductively Coupled Plasma Zoom-Time-of-Flight Mass Spectrometry

    NASA Astrophysics Data System (ADS)

    Dennis, Elise A.; Ray, Steven J.; Enke, Christie G.; Hieftje, Gary M.

    2016-03-01

    A zoom-time-of-flight mass spectrometer has been coupled to an inductively coupled plasma (ICP) ionization source. Zoom-time-of-flight mass spectrometry (zoom-TOFMS) combines two complementary types of velocity-based mass separation. Specifically, zoom-TOFMS alternates between conventional, constant-energy acceleration (CEA) TOFMS and energy-focused, constant-momentum acceleration (CMA) (zoom) TOFMS. The CMA mode provides a mass-resolution enhancement of 1.5-1.7× over CEA-TOFMS in the current, 35-cm ICP-zoom-TOFMS instrument geometry. The maximum resolving power (full-width at half-maximum) for the ICP-zoom-TOFMS instrument is 1200 for CEA-TOFMS and 1900 for CMA-TOFMS. The CMA mode yields detection limits of between 0.02 and 0.8 ppt, depending upon the repetition rate and integration time—compared with single ppt detection limits for CEA-TOFMS. Isotope-ratio precision is shot-noise limited at approximately 0.2% relative-standard deviation (RSD) for both CEA- and CMA-TOFMS at a 10 kHz repetition rate and an integration time of 3-5 min. When the repetition rate is increased to 43.5 kHz for CMA, the shot-noise limited, zoom-mode isotope-ratio precision is improved to 0.09% RSD for the same integration time.

  13. Temporal Analysis of Electrostatic Chuck Characteristics in Inductively Coupled Plasma

    NASA Astrophysics Data System (ADS)

    Shim, Gyu Il; Sugai, Hideo

    Johnsen-Rahbek electrostatic chuck (ESC) for holding a silicon wafer in semiconductor processing is investigated in inductively coupled plasma (ICP). Bi-layer model of the ESC consisting of a thick bulk layer and a thin interface layer is proposed. The resistance of each layer is obtained by measuring the ESC voltage-current (V-I) characteristic with and without the wafer in ICP, along with the voltage effectively applied to the interface layer. Surface charges stored in the interface layer capacitance are found by the time-integration of current in a turn-on phase of a ramped voltage. On the other hand, the chuck holding force is in situ obtained in a turn-off phase of slowly ramped voltage, from the critical conditions of helium gas pressurization for wafer de-chuck. The electrostatic force predicted on a basis of equivalent circuit in the bi-layer model coincides with the mechanical force obtained in the wafer de-touch experiments.

  14. Improvement of uniformity in a weakly magnetized inductively coupled plasma

    NASA Astrophysics Data System (ADS)

    Lee, W. H.; Cheong, H. W.; Kim, J. W.; Whang, K. W.

    2015-12-01

    Magnetic fields are applied to inductively coupled plasma (ICP) to achieve high plasma densities using electromagnets. If the magnetic fields are set up such that the magnitude of magnetic flux density on the substrate decreases with both radial and axial distances from the substrate’s center (here after referred to as M-ICP-A), the plasma density increases by 237% compared with that for ICP although the non-uniformity of the plasma density for M-ICP-A (11.1%) is higher than that for ICP (10.9%). As the rate of decrease in the magnitude of magnetic flux density on the substrate increases both radially and axially, the non-uniformity in the plasma density increases further. The increase in the non-uniformity for M-ICP-A was confirmed to arise from the flute instability. To suppress the flute instability, we arranged the magnitude of magnetic flux density on the substrate to increase with increasing distance from the substrate center both radially and axially (here after referred to as M-ICP-V). In this configuration, plasma fluctuations were not observed, hence the plasma density non-uniformity was lowered to 8.1%, although the measured plasma density was higher than that for M-ICP-A. The oxide etch-rate non-uniformity in M-ICP-V (2.5%) was also lower than that for ICP (5.2%) or that for M-ICP-A (21.4%).

  15. AETHER: A simulation platform for inductively coupled plasma

    NASA Astrophysics Data System (ADS)

    Turkoz, Emre; Celik, Murat

    2015-04-01

    An in-house code is developed to simulate the inductively coupled plasma (ICP). The model comprises the fluid, electromagnetic and transformer submodels. Fluid equations are solved to evaluate the plasma flow parameters, including the plasma and neutral densities, ion and neutral velocities, electron flux, electron temperature, and electric potential. The model relies on the ambipolar approximation and offers the evaluation of plasma parameters without solving the sheath region. The electromagnetic model handles the calculation of the electric and magnetic fields using the magnetic vector potential. The transformer model captures the effect of the matching circuit utilized in laboratory experiments for RF power deposition. The continuity and momentum equations are solved using finite volume method. The energy, electric potential, and magnetic vector potential equations are solved using finite difference method. The resulting linear systems of equations are solved with iterative solvers including Jacobi and GMRES. The code is written using the C++ programming language, it works in parallel and has graphical user interface. The model is applied to study ICP characteristics of a plasma confined within a cylindrical chamber with dielectric walls for two different power deposition cases. The results obtained from the developed model are verified using the plasma module of COMSOL Multiphysics. The model is also applied to a plasma source configuration, and it is demonstrated that there is an overall increase in the plasma potential when current is extracted from ICP with a biased wall electrode.

  16. Comparison between experiment and simulation for argon inductively coupled plasma

    SciTech Connect

    Gao Fei; Zhao Shuxia; Li Xiaosong; Wang Younian

    2009-11-15

    In order to include the nonlocal characteristics of electrons and investigate the inductively coupled plasma (ICP) resources more completely, we have developed a hybrid Monte Carlo (MC)/fluid hybrid model and calculated the axial and radial distributions of electron density, electron temperature, plasma potential, and electron energy distribution functions (EEDFs) of Ar discharge in a planar ICP. Furthermore, to make the model more practical, we still incorporate the effects of metastable atoms, whose sets of rate coefficients and density are, respectively, calculated through the electron MC part and fluid module. Besides, the corresponding Langmuir probe measurements are used to compare these data to validate the simulated results. Under all the selected discharge powers and pressures, the theoretically simulated and experimentally measured quantity profiles agree reasonably with each other, embodied in the generally identical magnitude ranges and spatial distributions. Furthermore, the interpretations about their detailed differences are given, which are based on the designs of both experimental schematic and model configuration. The analysis implements that the inclusions of electron-electron collision and a neutral density distribution into the hybrid model are likely to improve the comparison between the model predictions and experiment diagnostics. Furthermore, the evolution of plasma parameters and EEDFs with discharge conditions is discussed.

  17. Mode transition in CF4 + Ar inductively coupled plasma

    NASA Astrophysics Data System (ADS)

    Liu, Wei; Gao, Fei; Zhao, Shu-Xia; Li, Xue-Chun; Wang, You-Nian

    2013-12-01

    The E to H mode transitions are studied by a hairpin probe and optical emission spectroscopy in inductively coupled CF4 + Ar plasmas. Electron density, optical emission intensity of Ar, and the voltage and current are measured during the E to H mode transitions. It is found that the electron density and plasma emission intensity increase continuously at low pressure during the E to H mode transition, while they jump up discontinuously at high pressure. Meanwhile, the transition threshold power and △P (the power interval between E and H mode) increase by increasing the pressure. When the ratio of CF4 increases, the E to H mode transition happens at higher applied power, and meanwhile, the △P also significantly increases. Besides, the effects of CF4 gas ratio on the plasma properties and the circuit electrical properties in both pure E and H modes were also investigated. The electron density and plasma emission intensity both decrease upon increasing the ratio of CF4 at the two modes, due to the stronger electrons loss scheme. The applied voltages at E and H modes both increase as increasing the CF4 gas ratio, however the applied current at two modes behave just oppositely with the gas ratio.

  18. Prospective Motion Correction using Inductively-Coupled Wireless RF Coils

    PubMed Central

    Ooi, Melvyn B.; Aksoy, Murat; Maclaren, Julian; Watkins, Ronald D.; Bammer, Roland

    2013-01-01

    Purpose A novel prospective motion correction technique for brain MRI is presented that uses miniature wireless radio-frequency (RF) coils, or “wireless markers”, for position tracking. Methods Each marker is free of traditional cable connections to the scanner. Instead, its signal is wirelessly linked to the MR receiver via inductive coupling with the head coil. Real-time tracking of rigid head motion is performed using a pair of glasses integrated with three wireless markers. A tracking pulse-sequence, combined with knowledge of the markers’ unique geometrical arrangement, is used to measure their positions. Tracking data from the glasses is then used to prospectively update the orientation and position of the image-volume so that it follows the motion of the head. Results Wireless-marker position measurements were comparable to measurements using traditional wired RF tracking coils, with the standard deviation of the difference < 0.01 mm over the range of positions measured inside the head coil. RF safety was verified with B1 maps and temperature measurements. Prospective motion correction was demonstrated in a 2D spin-echo scan while the subject performed a series of deliberate head rotations. Conclusion Prospective motion correction using wireless markers enables high quality images to be acquired even during bulk motions. Wireless markers are small, avoid RF safety risks from electrical cables, are not hampered by mechanical connections to the scanner, and require minimal setup times. These advantages may help to facilitate adoption in the clinic. PMID:23813444

  19. Implantable flexible pressure measurement system based on inductive coupling.

    PubMed

    Oliveira, Cristina C; Sepúlveda, Alexandra T; Almeida, Nuno; Wardle, Brian L; da Silva, José Machado; Rocha, Luís A

    2015-02-01

    One of the currently available treatments for aortic aneurysms is endovascular aneurysm repair (EVAR). In spite of major advances in the operating techniques, complications still occur and lifelong surveillance is recommended. In order to reduce and even eliminate the commonly used surveillance imaging exams, as well as to reduce follow-up costs, new technological solutions are being pursued. In this paper, we describe the development, including design and performance characterization, of a flexible remote pressure measurement system based on inductive-coupling for post-EVAR monitoring purposes. The telemetry system architecture and operation are described and main performance characteristics discussed. The implantable sensor details are provided and its model is presented. Simulations with the reading circuit and the sensor's model were performed and compared with measurements carried out with air and a phantom as media, in order to characterize the telemetry system and validate the models. The transfer characteristic curve (pressure versus frequency) of the monitoring system was obtained with measurements performed with the sensor inside a controlled pressure vacuum chamber. Additional experimental results which proof the system functionality were obtained within a hydraulic test bench that emulates the aorta. Several innovative aspects, when compared to the state of the art, both in the sensor and in the telemetry system were achieved. PMID:25347867

  20. Uranium quantification in semen by inductively coupled plasma mass spectrometry.

    PubMed

    Todorov, Todor I; Ejnik, John W; Guandalini, Gustavo; Xu, Hanna; Hoover, Dennis; Anderson, Larry; Squibb, Katherine; McDiarmid, Melissa A; Centeno, Jose A

    2013-01-01

    In this study we report uranium analysis for human semen samples. Uranium quantification was performed by inductively coupled plasma mass spectrometry. No additives, such as chymotrypsin or bovine serum albumin, were used for semen liquefaction, as they showed significant uranium content. For method validation we spiked 2g aliquots of pooled control semen at three different levels of uranium: low at 5 pg/g, medium at 50 pg/g, and high at 1000 pg/g. The detection limit was determined to be 0.8 pg/g uranium in human semen. The data reproduced within 1.4-7% RSD and spike recoveries were 97-100%. The uranium level of the unspiked, pooled control semen was 2.9 pg/g of semen (n=10). In addition six semen samples from a cohort of Veterans exposed to depleted uranium (DU) in the 1991 Gulf War were analyzed with no knowledge of their exposure history. Uranium levels in the Veterans' semen samples ranged from undetectable (<0.8 pg/g) to 3350 pg/g. This wide concentration range for uranium in semen is consistent with known differences in current DU body burdens in these individuals, some of whom have retained embedded DU fragments. PMID:22944582

  1. Three-phase inductive-coupled structures for contactless PHEV charging system

    NASA Astrophysics Data System (ADS)

    Lee, Jia-You; Shen, Hung-Yu; Li, Cheng-Bin

    2016-07-01

    In this article, a new-type three-phase inductive-coupled structure is proposed for the contactless plug-in hybrid electric vehicle (PHEV) charging system regarding with SAE J-1773. Four possible three-phase core structures are presented and subsequently investigated by the finite element analysis. To study the correlation between the core geometric parameter and the coupling coefficient, the magnetic equivalent circuit model of each structure is also established. In accordance with the simulation results, the low reluctance and the sharing of flux path in the core material are achieved by the proposed inductive-coupled structure with an arc-shape and three-phase symmetrical core material. It results in a compensation of the magnetic flux between each phase and a continuous flow of the output power in the inductive-coupled structure. Higher coupling coefficient between inductive-coupled structures is achieved. A comparison of coupling coefficient, mutual inductance, and self-inductance between theoretical and measured results is also performed to verify the proposed model. A 1 kW laboratory scale prototype of the contactless PHEV charging system with the proposed arc-shape three-phase inductive-coupled structure is implemented and tested. An overall system efficiency of 88% is measured when two series lithium iron phosphate battery packs of 25.6 V/8.4 Ah are charged.

  2. An investigation of algebraic quantum dynamics for mesoscopic coupled electric circuits with mutual inductance

    NASA Astrophysics Data System (ADS)

    Pahlavani, H.; Kolur, E. Rahmanpour

    2016-08-01

    Based on the electrical charge discreteness, the Hamiltonian operator for the mutual inductance coupled quantum mesoscopic LC circuits has been found. The persistent current on two driven coupled mesoscopic electric pure L circuits (two quantum loops) has been obtained by using algebraic quantum dynamic approach. The influence of the mutual inductance on energy spectrum and quantum fluctuations of the charge and current for two coupled quantum electric mesoscopic LC circuits have been investigated.

  3. A tightly coupled non-equilibrium model for inductively coupled radio-frequency plasmas

    SciTech Connect

    Munafò, A. Alfuhaid, S. A. Panesi, M.; Cambier, J.-L.

    2015-10-07

    The objective of the present work is the development of a tightly coupled magneto-hydrodynamic model for inductively coupled radio-frequency plasmas. Non Local Thermodynamic Equilibrium (NLTE) effects are described based on a hybrid State-to-State approach. A multi-temperature formulation is used to account for thermal non-equilibrium between translation of heavy-particles and vibration of molecules. Excited electronic states of atoms are instead treated as separate pseudo-species, allowing for non-Boltzmann distributions of their populations. Free-electrons are assumed Maxwellian at their own temperature. The governing equations for the electro-magnetic field and the gas properties (e.g., chemical composition and temperatures) are written as a coupled system of time-dependent conservation laws. Steady-state solutions are obtained by means of an implicit Finite Volume method. The results obtained in both LTE and NLTE conditions over a broad spectrum of operating conditions demonstrate the robustness of the proposed coupled numerical method. The analysis of chemical composition and temperature distributions along the torch radius shows that: (i) the use of the LTE assumption may lead to an inaccurate prediction of the thermo-chemical state of the gas, and (ii) non-equilibrium phenomena play a significant role close the walls, due to the combined effects of Ohmic heating and macroscopic gradients.

  4. A tightly coupled non-equilibrium model for inductively coupled radio-frequency plasmas

    NASA Astrophysics Data System (ADS)

    Munafò, A.; Alfuhaid, S. A.; Cambier, J.-L.; Panesi, M.

    2015-10-01

    The objective of the present work is the development of a tightly coupled magneto-hydrodynamic model for inductively coupled radio-frequency plasmas. Non Local Thermodynamic Equilibrium (NLTE) effects are described based on a hybrid State-to-State approach. A multi-temperature formulation is used to account for thermal non-equilibrium between translation of heavy-particles and vibration of molecules. Excited electronic states of atoms are instead treated as separate pseudo-species, allowing for non-Boltzmann distributions of their populations. Free-electrons are assumed Maxwellian at their own temperature. The governing equations for the electro-magnetic field and the gas properties (e.g., chemical composition and temperatures) are written as a coupled system of time-dependent conservation laws. Steady-state solutions are obtained by means of an implicit Finite Volume method. The results obtained in both LTE and NLTE conditions over a broad spectrum of operating conditions demonstrate the robustness of the proposed coupled numerical method. The analysis of chemical composition and temperature distributions along the torch radius shows that: (i) the use of the LTE assumption may lead to an inaccurate prediction of the thermo-chemical state of the gas, and (ii) non-equilibrium phenomena play a significant role close the walls, due to the combined effects of Ohmic heating and macroscopic gradients.

  5. Horn-coupled, commercially-fabricated aluminum lumped-element kinetic inductance detectors for millimeter wavelengths.

    PubMed

    McCarrick, H; Flanigan, D; Jones, G; Johnson, B R; Ade, P; Araujo, D; Bradford, K; Cantor, R; Che, G; Day, P; Doyle, S; Leduc, H; Limon, M; Luu, V; Mauskopf, P; Miller, A; Mroczkowski, T; Tucker, C; Zmuidzinas, J

    2014-12-01

    We discuss the design, fabrication, and testing of prototype horn-coupled, lumped-element kinetic inductance detectors (LEKIDs) designed for cosmic microwave background studies. The LEKIDs are made from a thin aluminum film deposited on a silicon wafer and patterned using standard photolithographic techniques at STAR Cryoelectronics, a commercial device foundry. We fabricated 20-element arrays, optimized for a spectral band centered on 150 GHz, to test the sensitivity and yield of the devices as well as the multiplexing scheme. We characterized the detectors in two configurations. First, the detectors were tested in a dark environment with the horn apertures covered, and second, the horn apertures were pointed towards a beam-filling cryogenic blackbody load. These tests show that the multiplexing scheme is robust and scalable, the yield across multiple LEKID arrays is 91%, and the measured noise-equivalent temperatures for a 4 K optical load are in the range 26±6 μK√s. PMID:25554282

  6. Horn-coupled, commercially-fabricated aluminum lumped-element kinetic inductance detectors for millimeter wavelengths

    SciTech Connect

    McCarrick, H. Flanigan, D.; Jones, G.; Johnson, B. R.; Araujo, D.; Limon, M.; Luu, V.; Miller, A.; Ade, P.; Doyle, S.; Tucker, C.; Bradford, K.; Che, G.; Cantor, R.; Day, P.; Leduc, H.; Mauskopf, P.; Mroczkowski, T.; Zmuidzinas, J.

    2014-12-15

    We discuss the design, fabrication, and testing of prototype horn-coupled, lumped-element kinetic inductance detectors (LEKIDs) designed for cosmic microwave background studies. The LEKIDs are made from a thin aluminum film deposited on a silicon wafer and patterned using standard photolithographic techniques at STAR Cryoelectronics, a commercial device foundry. We fabricated 20-element arrays, optimized for a spectral band centered on 150 GHz, to test the sensitivity and yield of the devices as well as the multiplexing scheme. We characterized the detectors in two configurations. First, the detectors were tested in a dark environment with the horn apertures covered, and second, the horn apertures were pointed towards a beam-filling cryogenic blackbody load. These tests show that the multiplexing scheme is robust and scalable, the yield across multiple LEKID arrays is 91%, and the measured noise-equivalent temperatures for a 4 K optical load are in the range 26±6 μK√(s)

  7. Characteristics of pulsed dual frequency inductively coupled plasma

    NASA Astrophysics Data System (ADS)

    Seo, Jin Seok; Kim, Kyoung Nam; Kim, Ki Seok; Kim, Tae Hyung; Yeom, Geun Young

    2015-01-01

    To control the plasma characteristics more efficiently, a dual antenna inductively coupled plasma (DF-ICP) source composed of a 12-turn inner antenna operated at 2 MHz and a 3-turn outer antenna at 13.56 MHz was pulsed. The effects of pulsing to each antenna on the change of plasma characteristics and SiO2 etch characteristics using Ar/C4F8 gas mixtures were investigated. When the duty percentage was decreased from continuous wave (CW) mode to 30% for the inner or outer ICP antenna, decrease of the average electron temperature was observed for the pulsing of each antenna. Increase of the CF2/F ratio was also observed with decreasing duty percentage of each antenna, indicating decreased dissociation of the C4F8 gas due to the decreased average electron temperature. When SiO2 etching was investigated as a function of pulse duty percentage, increase of the etch selectivity of SiO2 over amorphous carbon layer (ACL) was observed while decreasing the SiO2 etch rate. The increase of etch selectivity was related to the change of gas dissociation characteristics, as observed by the decrease of average electron temperature and consequent increase of the CF2/F ratio. The decrease of the SiO2 etch rate could be compensated for by using the rf power compensated mode, that is, by maintaining the same time-average rf power during pulsing, instead of using the conventional pulsing mode. Through use of the power compensated mode, increased etch selectivity of SiO2/ACL similar to the conventional pulsing mode could be observed without significant decrease of the SiO2 etch rate. Finally, by using the rf power compensated mode while pulsing rf powers to both antennas, the plasma uniformity over the 300 mm diameter substrate could be improved from 7% for the CW conditions to about around 3.3% with the duty percentage of 30%.

  8. Aerosol detection efficiency in inductively coupled plasma mass spectrometry

    DOE PAGESBeta

    Hubbard, Joshua A.; Zigmond, Joseph A.

    2016-03-02

    We used an electrostatic size classification technique to segregate particles of known composition prior to being injected into an inductively coupled plasma mass spectrometer (ICP-MS). Moreover, we counted size-segregated particles with a condensation nuclei counter as well as sampled with an ICP-MS. By injecting particles of known size, composition, and aerosol concentration into the ICP-MS, efficiencies of the order of magnitude aerosol detection were calculated, and the particle size dependencies for volatile and refractory species were quantified. Similar to laser ablation ICP-MS, aerosol detection efficiency was defined as the rate at which atoms were detected in the ICP-MS normalized bymore » the rate at which atoms were injected in the form of particles. This method adds valuable insight into the development of technologies like laser ablation ICP-MS where aerosol particles (of relatively unknown size and gas concentration) are generated during ablation and then transported into the plasma of an ICP-MS. In this study, we characterized aerosol detection efficiencies of volatile species gold and silver along with refractory species aluminum oxide, cerium oxide, and yttrium oxide. Aerosols were generated with electrical mobility diameters ranging from 100 to 1000 nm. In general, it was observed that refractory species had lower aerosol detection efficiencies than volatile species, and there were strong dependencies on particle size and plasma torch residence time. Volatile species showed a distinct transition point at which aerosol detection efficiency began decreasing with increasing particle size. This critical diameter indicated the largest particle size for which complete particle detection should be expected and agreed with theories published in other works. Aerosol detection efficiencies also displayed power law dependencies on particle size. Aerosol detection efficiencies ranged from 10-5 to 10-11. Free molecular heat and mass transfer theory was

  9. Aerosol detection efficiency in inductively coupled plasma mass spectrometry

    NASA Astrophysics Data System (ADS)

    Hubbard, Joshua A.; Zigmond, Joseph A.

    2016-05-01

    An electrostatic size classification technique was used to segregate particles of known composition prior to being injected into an inductively coupled plasma mass spectrometer (ICP-MS). Size-segregated particles were counted with a condensation nuclei counter as well as sampled with an ICP-MS. By injecting particles of known size, composition, and aerosol concentration into the ICP-MS, efficiencies of the order of magnitude aerosol detection were calculated, and the particle size dependencies for volatile and refractory species were quantified. Similar to laser ablation ICP-MS, aerosol detection efficiency was defined as the rate at which atoms were detected in the ICP-MS normalized by the rate at which atoms were injected in the form of particles. This method adds valuable insight into the development of technologies like laser ablation ICP-MS where aerosol particles (of relatively unknown size and gas concentration) are generated during ablation and then transported into the plasma of an ICP-MS. In this study, we characterized aerosol detection efficiencies of volatile species gold and silver along with refractory species aluminum oxide, cerium oxide, and yttrium oxide. Aerosols were generated with electrical mobility diameters ranging from 100 to 1000 nm. In general, it was observed that refractory species had lower aerosol detection efficiencies than volatile species, and there were strong dependencies on particle size and plasma torch residence time. Volatile species showed a distinct transition point at which aerosol detection efficiency began decreasing with increasing particle size. This critical diameter indicated the largest particle size for which complete particle detection should be expected and agreed with theories published in other works. Aerosol detection efficiencies also displayed power law dependencies on particle size. Aerosol detection efficiencies ranged from 10- 5 to 10- 11. Free molecular heat and mass transfer theory was applied, but

  10. A new continuous calibration method for inductively coupled plasma spectrometry.

    PubMed

    Paredes, E; Maestre, S E; Todolí, J L

    2006-01-01

    A new calibration method was developed and applied to inductively coupled plasma atomic emission spectrometry. External calibration was performed as follows. A container was filled with a given volume of deionized (V(p)) water. Then a concentrated standard was introduced at a controlled rate (Q(e)) into the tank by means of a peristaltic pump. The resulting solution was stirred throughout the experiment. Simultaneously, the solution inside the tank was pumped from the vessel to the plasma at a given rate (Q(s)). The signal was continuously recorded. The variation of the concentration of the solution leaving the tank with time was determined by applying a basic equation of stirred tanks. The representation of the emission intensity versus the time and the further conversion of the time scale into a concentration scale gave rise to the calibration line. The best results in terms of linearity were achieved for V(p)=15 cm3, Q(e)=0.6-0.75 ml min(-1) and Q(s)=1-1.2 ml min(-1). Graphs with more than 40 standards were obtained within about 10 min. The results found were not statistically different from those afforded by the conventional calibration method. In addition, the new method was faster and supplied better linearity and precision than the conventional one. Another advantage of the stirred tank was that procedures such as dynamic calibration and standard additions could be easily and quickly applied, thus shortening the analysis time. A complete analysis following these procedures based on the measurement of 30 standards took about 5 min. Several synthetic as well as certified samples (i.e., bovine liver, mussel tissue and powdered milk) were analyzed with the stirred tank by applying four different calibration methodologies (i.e., external calibration, internal calibration, standard additions and a combination of internal standardization and standard additions), with the combination of internal standardization and standard additions being the method that provided

  11. RELIABLE ANALYSES OF WATER BY INDUCTIVELY COUPLED PLASMA EMISSION SPECTROSCOPY. ANALYTICAL CHEMISTRY BRANCH

    EPA Science Inventory

    Reduction of stray light in the inductively coupled plasma emission spectrometer (ICPES) has greatly increased its reliability as a technique for the multielemental analysis of water. Because of interferences introduced by matrix elements, reliable analysis of some less-sensitive...

  12. How to induce multiple delays in coupled chaotic oscillators?

    SciTech Connect

    Bhowmick, Sourav K.; Ghosh, Dibakar; Roy, Prodyot K.; Kurths, Jürgen; Dana, Syamal K.

    2013-12-15

    Lag synchronization is a basic phenomenon in mismatched coupled systems, delay coupled systems, and time-delayed systems. It is characterized by a lag configuration that identifies a unique time shift between all pairs of similar state variables of the coupled systems. In this report, an attempt is made how to induce multiple lag configurations in coupled systems when different pairs of state variables attain different time shift. A design of coupling is presented to realize this multiple lag synchronization. Numerical illustration is given using examples of the Rössler system and the slow-fast Hindmarsh-Rose neuron model. The multiple lag scenario is physically realized in an electronic circuit of two Sprott systems.

  13. How to induce multiple delays in coupled chaotic oscillators?

    PubMed

    Bhowmick, Sourav K; Ghosh, Dibakar; Roy, Prodyot K; Kurths, Jürgen; Dana, Syamal K

    2013-12-01

    Lag synchronization is a basic phenomenon in mismatched coupled systems, delay coupled systems, and time-delayed systems. It is characterized by a lag configuration that identifies a unique time shift between all pairs of similar state variables of the coupled systems. In this report, an attempt is made how to induce multiple lag configurations in coupled systems when different pairs of state variables attain different time shift. A design of coupling is presented to realize this multiple lag synchronization. Numerical illustration is given using examples of the Rössler system and the slow-fast Hindmarsh-Rose neuron model. The multiple lag scenario is physically realized in an electronic circuit of two Sprott systems. PMID:24387554

  14. Low wireless power transfer using Inductive Coupling for mobile phone charger

    NASA Astrophysics Data System (ADS)

    Fareq, M.; Fitra, M.; Irwanto, M.; Hasan, Syafruddin; Arinal, M.

    2014-04-01

    A wireless power transfer (WPT) using inductive coupling for mobile phone charger is studied. The project is offer to study and fabricate WPT using inductive coupling for mobile phone charger that will give more information about distance is effect for WPT performance and WPT is not much influenced by the presence of hands, books and types of plastics. The components used to build wireless power transfer can be divided into 3 parts components, the transceiver for power transmission, the inductive coils in this case as the antenna, receiver and the rectifier which act convert AC to DC. Experiments have been conducted and the wireless power transfer using inductive coupling is suitable to be implemented for mobile phone charger.

  15. Multiple beam induction accelerators for heavy ion fusion

    NASA Astrophysics Data System (ADS)

    Seidl, Peter A.; Barnard, John J.; Faltens, Andris; Friedman, Alex; Waldron, William L.

    2014-01-01

    Induction accelerators are appealing for heavy-ion driven inertial fusion energy (HIF) because of their high efficiency and their demonstrated capability to accelerate high beam current (≥10 kA in some applications). For the HIF application, accomplishments and challenges are summarized. HIF research and development has demonstrated the production of single ion beams with the required emittance, current, and energy suitable for injection into an induction linear accelerator. Driver scale beams have been transported in quadrupole channels of the order of 10% of the number of quadrupoles of a driver. We review the design and operation of induction accelerators and the relevant aspects of their use as drivers for HIF. We describe intermediate research steps that would provide the basis for a heavy-ion research facility capable of heating matter to fusion relevant temperatures and densities, and also to test and demonstrate an accelerator architecture that scales well to a fusion power plant.

  16. Experimental demonstration of the equivalence of inductive and strongly coupled magnetic resonance wireless power transfer

    NASA Astrophysics Data System (ADS)

    Ricketts, David S.; Chabalko, Matthew J.; Hillenius, Andrew

    2013-02-01

    In this work, we show experimentally that wireless power transfer (WPT) using strongly coupled magnetic resonance (SCMR) and traditional induction are equivalent. We demonstrate that for a given coil separation, and to within 4%, strongly coupled magnetic resonance and traditional induction produce the same theoretical efficiency of wireless power transfer versus distance. Moreover, we show that the difference between traditional induction and strongly coupled magnetic resonance is in the implementation of the impedance matching network where strongly coupled magnetic resonance uses the mini-loop impedance match. The mini-loop impedance mach provides a low-loss, high-ratio impedance transformation that makes it desirable for longer distance wireless power transfer, where large impedance transformations are needed to maximize power transfer.

  17. Ultra-wide bandwidth improvement of piezoelectric energy harvesters through electrical inductance coupling

    NASA Astrophysics Data System (ADS)

    Abdelmoula, H.; Abdelkefi, A.

    2015-11-01

    The design and analysis of innovative ultra-wide bandwidth piezoelectric energy harvesters are deeply investigated. An electrical inductance is considered in the harvester's circuit to be connected in series or parallel to a load resistance. A lumped-parameter model is used to model the electromechanical response of the harvester when subjected to harmonic excitations. A linear comprehensive analysis is performed to investigate the effects of an electrical inductance on the coupled frequencies and damping of the harvester. It is shown that including an electrical inductance connected in series or in parallel to an electrical load resistance can result in the appearance of a second coupled frequency of electrical type. The results show that the inclusion of an inductance may give the opportunity to tune one of the coupled frequencies of mechanical and electrical types to the available excitation frequency in the environment. Using the gradient method, an optimization analysis is then performed to determine the optimum values of the electrical inductance and load resistance that maximize the harvested power. It is demonstrated that, for each excitation frequency, there is a combination of optimum values of the electrical inductance and resistance in such a way an optimum constant value of the harvested power is found. Numerical analysis is then performed to show the importance of considering an additional inductance in the harvester's circuitry in order to design broadband energy harvesters. The results show that the presence of the second coupled frequency of electrical type due to the inductance gives the possibility to design optimal broadband inductive-resistive piezoelectric energy harvesters with minimum displacement due to shunt damping effect.

  18. Speeded induction under uncertainty: the influence of multiple categories and feature conjunctions.

    PubMed

    Newell, Ben R; Paton, Helen; Hayes, Brett K; Griffiths, Oren

    2010-12-01

    When people are uncertain about the category membership of an item (e.g., Is it a dog or a dingo?), research shows that they tend to rely only on the dominant or most likely category when making inductions (e.g., How likely is it to befriend me?). An exception has been reported using speeded induction judgments where participants appeared to use information from multiple categories to make inductions (Verde, Murphy, & Ross, 2005). In two speeded induction studies, we found that participants tended to rely on the frequency with which features co-occurred when making feature predictions, independently of category membership. This pattern held whether categories were considered implicitly (Experiment 1) or explicitly (Experiment 2) prior to feature induction. The results converge with other recent work suggesting that people often rely on feature conjunction information, rather than category boundaries, when making inductions under uncertainty. PMID:21169582

  19. Investigation of large-area multicoil inductively coupled plasma sources using three-dimensional fluid model

    NASA Astrophysics Data System (ADS)

    Brcka, Jozef

    2016-07-01

    A multi inductively coupled plasma (ICP) system can be used to maintain the plasma uniformity and increase the area processed by a high-density plasma. This article presents a source in two different configurations. The distributed planar multi ICP (DM-ICP) source comprises individual ICP sources that are not overlapped and produce plasma independently. Mutual coupling of the ICPs may affect the distribution of the produced plasma. The integrated multicoil ICP (IMC-ICP) source consists of four low-inductance ICP antennas that are superimposed in an azimuthal manner. The identical geometry of the ICP coils was assumed in this work. Both configurations have highly asymmetric components. A three-dimensional (3D) plasma model of the multicoil ICP configurations with asymmetric features is used to investigate the plasma characteristics in a large chamber and the operation of the sources in inert and reactive gases. The feasibility of the computational calculation, the speed, and the computational resources of the coupled multiphysics solver are investigated in the framework of a large realistic geometry and complex reaction processes. It was determined that additional variables can be used to control large-area plasmas. Both configurations can form a plasma, that azimuthally moves in a controlled manner, the so-called “sweeping mode” (SM) or “polyphase mode” (PPM), and thus they have the potential for large-area and high-density plasma applications. The operation in the azimuthal mode has the potential to adjust the plasma distribution, the reaction chemistry, and increase or modulate the production of the radicals. The intrinsic asymmetry of the individual coils and their combined operation were investigated within a source assembly primarily in argon and CO gases. Limited investigations were also performed on operation in CH4 gas. The plasma parameters and the resulting chemistry are affected by the geometrical relation between individual antennas. The aim of

  20. Determination of plutonium in urine: evaluation of electrothermal vaporization inductively coupled plasma mass spectroscopy

    SciTech Connect

    Pietrzak, R.; Kaplan, E.

    1996-11-01

    Mass spectroscopy has the distinct advantage of detecting atoms rather than radioactive decay products for nuclides of low specific activity. Electrothermal vaporization (ETV) is an efficient means of introducing small volumes of prepared samples into an inductively coupled mass spectrometer to achieve the lowest absolute detection limits. The operational characteristics and capabilities of electrothermal vaporization inductively coupled mass spectrometer mass spectroscopy were evaluated. We describe its application as a detection method for determining Pu in urine, in conjunction with a preliminary separation technique to avoid matrix suppression of the signal.

  1. MICROSCALE FLOW INJECTION AND MICROBORE HIGH-PERFORMANCE LIQUID CHROMATORGRAPHY COUPLED WITH INDUCTIVELY COUPLED PLASMA MASS SPECTROMETRY VIA A HIGH-EFFICIENCY NEBULIZER

    EPA Science Inventory

    A high-effeciency nebulizer has been used for coupling microscale flow injection and microbore high-performance liquid chromatography with inductively coupled plasma mass spectrometry (ICPMS). The microscale flow injection system was configured to minimize band broadening between...

  2. Induced magnetic-field effects in inductively coupled plasmas

    SciTech Connect

    Cohen, R.H.; Rognlien, T.D.

    1995-11-04

    In inductive plasma sources, the rapid spatial decay of the electric field arising from the skin effect produces a large radio frequency (RF) magnetic field via Faraday`s law. We previously determined that this magnetic field leads to a reduction of the electron density in the skin region, as well as a reduction in the collisionless heating rate. The electron deficit leads to the formation of an electrostatic potential which pulls electrons in to restore quasineutrality. Here we calculate the electron density including both the induced and electrostatic fields. If the wave frequency is not too low, the ions respond only to the averaged fields, and hence the electrostatic field is oscillatory, predominantly at the second harmonic of the applied field. We calculate the potential required to establish a constant electron density, and compare with numerical orbit-code calculations. For times short compared to ion transit times, the quasineutral density is just the initial ion density. For timescales long enough that the ions can relax, the density profile can be found from the solution of fluid equations with an effective (ponderomotive-like) potential added. Although the time-varying electrostatic potential is an extra source of heating, the net effect of the induced magnetic and electrostatic fields through trapping, early turning, and direct heating is a significant reduction in collisionless heating for parameters of interest.

  3. Characterization of an inductively coupled plasma source with convergent nozzle

    NASA Astrophysics Data System (ADS)

    Dropmann, Michael; Clements, Kathryn; Edgren, Josh; Laufer, Rene; Herdrich, Georg; Matthews, Lorin; Hyde, Truell

    2015-11-01

    The inductively heated plasma generator (IPG6-B) located in the CASPER labs at Baylor University has recently been characterized for both air, nitrogen and helium. A primary area of research within the intended scope of the instrument is the analysis of material degradation under high heat fluxes such as those imposed by a plasma during atmospheric entry of a spacecraft and at the divertor within various fusion experiment. In order to achieve higher flow velocities and respectively higher heat fluxes, a new exit flange has been designed to allow the installation of nozzles with varying geometries at the exit of the plasma generator. This paper will discuss characterization of the plasma generator for a convergent nozzle accelerating the plasma jet to supersonic velocity. The diagnostics employed include a cavity calorimeter to measure the total plasma power, a Pitot probe to measure stagnation pressure and a heat flux probe to measure the local heat flux. Radial profiles of stagnation pressure and heat flux allowing the determination of the local plasma enthalpy in the plasma jet will be presented. Support from the NSF and the DOE (award numbers PHY-1262031 and PHY-1414523) is gratefully acknowledged.

  4. Collisionless electron heating in periodic arrays of inductively coupled plasmas

    SciTech Connect

    Czarnetzki, U.; Tarnev, Kh.

    2014-12-15

    A novel mechanism of collisionless heating in large planar arrays of small inductive coils operated at radio frequencies is presented. In contrast to the well-known case of non-local heating related to the transversal conductivity, when the electrons move perpendicular to the planar coil, we investigate the problem of electrons moving in a plane parallel to the coils. Two types of periodic structures are studied. Resonance velocities where heating is efficient are calculated analytically by solving the Vlasov equation. Certain scaling parameters are identified. The concept is further investigated by a single particle simulation based on the ergodic principle and combined with a Monte Carlo code allowing for collisions with Argon atoms. Resonances, energy exchange, and distribution functions are obtained. The analytical results are confirmed by the numerical simulation. Pressure and electric field dependences are studied. Stochastic heating is found to be most efficient when the electron mean free path exceeds the size of a single coil cell. Then the mean energy increases approximately exponentially with the electric field amplitude.

  5. Yessotoxin as a tool to study induction of multiple cell death pathways.

    PubMed

    Korsnes, Mónica Suárez

    2012-07-01

    This work proposes to use the marine algal toxin yessotoxin (YTX) to establish reference model experiments to explore medically valuable effects from induction of multiple cell death pathways. YTX is one of few toxins reported to make such induction. It is a small molecule compound which at low concentrations can induce apoptosis in primary cultures, many types of cells and cell lines. It can also induce a non-apoptotic form of programmed cell death in BC3H1 myoblast cell lines. The present contribution reviews arguments that this type of induction may have principal interest outside this particular example. One principal effect of medical interest may be that cancer cells will not so easily adapt to the synergistic effects from induction of more than one death pathway as compared to induction of only apoptosis. PMID:22852069

  6. Double clicking for site-specific coupling of multiple enzymes.

    PubMed

    Lim, Sung In; Cho, Jinhwan; Kwon, Inchan

    2015-09-14

    A method to site-specifically couple multiple enzymes is reported. The approach is based on the site-specific incorporation of a clickable non-natural amino acid into enzymes and two compatible click reactions. The multi-enzyme reaction system exhibited enhanced catalytic efficiency over the respective free enzymes. PMID:26191550

  7. Eyetracking Reveals Multiple-Category Use in Induction

    ERIC Educational Resources Information Center

    Chen, Stephanie Y.; Ross, Brian H.; Murphy, Gregory L.

    2016-01-01

    Category information is used to predict properties of new category members. When categorization is uncertain, people often rely on only one, most likely category to make predictions. Yet studies of perception and action often conclude that people combine multiple sources of information near-optimally. We present a perception-action analog of…

  8. Macroscopic quantum effects in capacitively- and inductively-coupled intrinsic Josephson junctions

    NASA Astrophysics Data System (ADS)

    Koyama, T.; Machida, M.

    2009-03-01

    A theory for macroscopic quantum tunneling (MQT) in intrinsic Josephson junction stacks is formulated. Both capacitive and inductive couplings between junctions are taken into account. We calculate the escape rate in the switching to the first resistive branch in the quantum regime. It is shown that the enhancement of the escape rate is caused mainly by the capacitive coupling between junctions in IJJ's with small in-plane area of ~ 1μm2.

  9. Determination of metals in marine species by microwave digestion and inductively coupled plasma mass spectrometry analysis

    NASA Astrophysics Data System (ADS)

    Yang, Karl X.; Swami, Kamal

    2007-10-01

    A microwave digestion method suitable for determination of multiple elements in marine species was developed, with the use of cold vapor atomic spectrometry for the detection of Hg, and inductively coupled plasma mass spectrometry for all of the other elements. An optimized reagent mixture composed of 2 ml of HNO 3, 2 ml of H 2O 2 and 0.3 ml of HF used in microwave digestion of about 0.15 g (dry weight) of sample was found to give the best overall recoveries of metals in two standard reference materials. In the oyster tissue standard reference material (SRM 1566b), recoveries of Na, Al, K, V, Co, Zn, Se, Sr, Ag, Cd, Ni, and Pb were between 90% and 110%; Mg, Mn, Fe, Cu, As, and Ba recoveries were between 85% and 90%; Hg recovery was 81%; and Ca recovery was 64%. In a dogfish certified reference material (DORM-2), the recoveries of Al, Cr, Mn, Se, and Hg were between 90% and 110%; Ni, Cu, Zn, and As recoveries were about 85%; and Fe recovery was 112%. Method detection limits of the elements were established. Metal concentrations in flounder, scup, and blue crab samples collected from coastal locations around Long Island and in the Hudson River estuary were determined.

  10. Determination of long-lived actinides in soil leachates by inductively coupled plasma: Mass spectrometry

    SciTech Connect

    Crain, J.S.; Smith, L.L.; Yaeger, J.S.; Alvarado, J.A.

    1994-06-01

    Inductively coupled plasma -- mass spectrometry (ICP-MS) was used to concurrently determine multiple long-lived (t{sub 1/2} > 10{sup 4} y) actinide isotopes in soil samples. Ultrasonic nebulization was found to maximize instrument sensitivity. Instrument detection limits for actinides in solution ranged from 50 mBq L{sup {minus}1} ({sup 239}Pu) to 2 {mu}Bq L{sup {minus}1} ({sup 235}U) Hydride adducts of {sup 232}Th and {sup 238}U interfered with the determinations of {sup 233}U and {sup 239} Pu; thus, extraction chromatography was, used to eliminate the sample matrix, concentrate the analytes, and separate uranium from the other actinides. Alpha spectrometric determinations of {sup 230}Th, {sup 239}Pu, and the {sup 234}U/{sup 238}U activity ratio in soil leachates compared well with ICP-MS determinations; however, there were some small systematic differences (ca. 10%) between ICP-MS and a-spectrometric determinations of {sup 234}U and {sup 238}U activities.

  11. Characterization of natural water resources in Israel by inductively coupled plasma mass spectrometry

    NASA Astrophysics Data System (ADS)

    Halicz, L.; Becker, J. S.; Pickhardt, C.; Gavrieli, I.; Burg, A.; Nishri, A.; Platzner, I. T.

    2006-03-01

    Analytical procedures are applied for the determination of plutonium, uranium and strontium concentration, their isotope ratios and the analysis of rare earth elements (REE) at trace and ultratrace level in natural Israeli water resources with relatively high matrix content (Na = 20-150 mg L-1, Mg = 20-50 mg L-1 and Ca = 40-100 mg L-1) by inductively coupled plasma mass spectrometry (ICP-MS). To avoid matrix and clogging effects on the cones during mass spectrometric measurements and to analyze Pu and REE at extremely low concentration levels, separation procedures from matrices were applied. An extremely low Pu contamination of the Sea of Galilee was observed due to global nuclear fallout after the nuclear weapons test in the 1960s. The detection limit, for example, for 239Pu was found to be <10-19 g mL-1. For uranium a natural variation of the 234U/238U isotope ratios by a factor of up to 2 in comparison to the IUPAC table value was detected using ICP-MS. This paper discusses the application of double-focusing sector field ICP-MS with single and multiple ion collection as well as quadrupole-based ICP-MS (ICP-QMS) for the quantitative determination of REE, plutonium, uranium and strontium and their isotope ratios after analyte/matrix separation at trace and ultratrace levels in natural water.

  12. Studying Arsenite-Humic Acid Complexation Using Size Exclusion Chromatography-Inductively Coupled Plasma Mass Spectrometry

    PubMed Central

    Liu, Guangliang; Cai, Yong

    2012-01-01

    Arsenic (As) can form complexes with dissolved organic matter (DOM), which affects the fate of arsenic in waste sites and natural environments. It remains a challenge to analyze DOM-bound As, in particular by using a direct chromatographic separation method. Size exclusion chromatography (SEC) hyphenated with UV spectrophotometer and inductively coupled plasma mass spectrometry (ICP-MS) was developed to characterize the complexation of arsenite (AsIII) with DOM. This SEC-UV-ICP-MS method is able to differentiate AsIII-DOM complexes from free As species and has the advantage of direct determination of both free and DOM-bound AsIII through mild separation. The suitability of this method for studying AsIII-DOM complexation was demonstrated by its application, in combination with the Scatchard plot and nonlinear regression of ligand binding model, for characterizing AsIII complexation with humic acid (HA) in the absence or presence of natural sand. The results suggest that, consistent with polyelectrolytic nature of HA, the AsIII-HA complexation should be accounted for by multiple classes of binding sites. By loosely classifying the binding sites into strong (S1) and weak (S2) sites, the apparent stability constants (Ks) of the resulting As-DOM complexes were calculated as log Ks1 = 6.5–7.1 while log Ks2 = 4.7–5.0. PMID:22664255

  13. Implementation of Inductive Magnetosphere-Ionosphere Coupling and its Effects on Global MHD Magnetospheric Simulations

    NASA Astrophysics Data System (ADS)

    Xi, S.; Lotko, W.; Zhang, B.; Brambles, O.; Wiltberger, M. J.; Lyon, J.; Merkin, V. G.

    2010-12-01

    In global modeling, magnetosphere-ionosphere (MI) coupling physically connects a global magnetospheric (GM) model and a global ionospheric-thermospheric (GIT) model. The field-aligned current from the GM model and the conductance distributions from the GIT model are used in a Poisson equation derived from the ionospheric Ohm's law combined with current continuity to determine the electrostatic potential in the ionosphere. In current GM models, this electrostatic potential is mapped to the inner boundary of the GM simulation to determine electrostatic boundary conditions on the electric field and MHD velocity there. Inductive effects and the finite Alfven transit time between the low-altitude GM boundary and the high-altitude GIT boundary (MI gap region) are neglected in this formulation of MI coupling. Using fields and currents derived from Lyon-Fedder-Mobarry GM simulations, and conductance distributions derived from its standalone empirical conductance model in the MI coupling Poisson equation, we have computed the fast Fourier transform of the electrostatic field at the low-altitude LFM simulation boundary as described above, and the FFT of the inductive electric field at the boundary under the assumption that μ 0 Σ P vA ≤ 1, where Σ P is the ionospheric Pedersen conductance and vA is the smallest value of the Alfven speed in the MI gap region. In this regime, the complete electric field at the low-altitude simulation boundary includes the usual mapped electrostatic field with an inductive addition for which the finite Alfven transit time and the diversion of field-aligned into polarization currents in the gap region are negligible (Lotko, 2004). By comparing the boundary-averaged spectra of the electrostatic and so-determined inductive fields, we confirm that the purely electrostatic formulation of MI coupling is valid when the MHD state varies on times scales exceeding about 200 s. For faster MHD time variations, the inductive electric field is shown to

  14. INDUCTIVELY COUPLED PLASMA-ATOMIC EMISSION SPECTROMETRIC ANALYSIS OF ENVIRONMENTAL SAMPLES USING ULTRASONIC NEBULIZATION

    EPA Science Inventory

    Ultrasonic and pneumatic nebulizers used in inductively coupled plasma-atomic emission spectrometry (ICP-AES) are compared in the analysis of standard materials and environmental samples. Results verify that ICP-AES with ultrasonic nebulization is capable of lower detection limit...

  15. Determination of Arsenic in Sinus Wash and Tap Water by Inductively Coupled Plasma-Mass Spectrometry

    ERIC Educational Resources Information Center

    Donnell, Anna M.; Nahan, Keaton; Holloway, Dawone; Vonderheide, Anne P.

    2016-01-01

    Arsenic is a toxic element to which humans are primarily exposed through food and water; it occurs as a result of human activities and naturally from the earth's crust. An experiment was developed for a senior level analytical laboratory utilizing an Inductively Coupled Plasma-Mass Spectrometer (ICP-MS) for the analysis of arsenic in household…

  16. INTERLABORATORY STUDY OF INDUCTIVELY COUPLED PLASMA ATOMIC EMISSION SPECTROSCOPY METHOD 6010 AND DIGESTION METHOD 3050

    EPA Science Inventory

    The design, execution, and results of an interlaboratory study of Method 6010, 'Inductively Coupled Plasma Atomic Emission Spectroscopy,' are described. The study examined the application of the method to the analysis of solid-waste materials for 23 elements. Part of the interlab...

  17. Inductively coupled plasma-atomic emission spectroscopy: The determination of trace impurities in uranium hexafluoride

    NASA Astrophysics Data System (ADS)

    Floyd, M. A.; Morrow, R. W.; Farrar, R. B.

    An analytical method has been developed for the determination of trace impurities in high-purity uranium hexafluoride using liquid-liquid extraction of the uranium from the trace impurities followed by analysis with inductively coupled plasma-atomic emission spectroscopy. Detection limits, accuracy, and precision data are presented.

  18. ULTRASONIC NEBULIZATION AND ARSENIC VALENCE STATE CONSIDERATIONS PRIOR TO DETERMINATION VIA INDUCTIVELY COUPLED PLASMA MASS SPECTROMETRY

    EPA Science Inventory

    An ultrasonic nebulizer (USN) was utilized as a sample introduction device for an inductively coupled plasma mass spectrometer in an attempt to increase the sensitivity for As. The USN produced a valence state response difference for As. The As response was suppressed approximate...

  19. DETERMINATION OF BROMATE IN DRINKING WATERS BY ION CHROMATOGRAPHY WITH INDUCTIVELY COUPLED PLASMA MASS SPECTROMETRIC DETECTION

    EPA Science Inventory

    Bromate is a disinfection by-product in drinking water, formed during the ozonation of source water containing bromide. An inductively coupled plasma mass spectrometer is combined with an ion chromatograph for the analysis of bromate in drinking waters. Three chromatographic colu...

  20. INDUCTIVELY COUPLED ARGON PLASMA AS AN ION SOURCE FOR MASS SPECTROMETRIC DETERMINATION OF TRACE ELEMENTS

    EPA Science Inventory

    Solution aerosols are injected into an inductively coupled argon plasma (ICP) to generate a relatively high number density of positive ions derived from elemental constituents. A small fraction of these ions is extracted through a sampling orifice into a differentially pumped vac...

  1. In situ calibration of inductively coupled plasma-atomic emission and mass spectroscopy

    DOEpatents

    Braymen, Steven D.

    1996-06-11

    A method and apparatus for in situ addition calibration of an inductively coupled plasma atomic emission spectrometer or mass spectrometer using a precision gas metering valve to introduce a volatile calibration gas of an element of interest directly into an aerosol particle stream. The present situ calibration technique is suitable for various remote, on-site sampling systems such as laser ablation or nebulization.

  2. Atlas of atomic spectral lines of plutonium emitted by an inductively coupled plasma

    SciTech Connect

    Edelson, M.C.; DeKalb, E.L.; Winge, R.K.; Fassel, V.A.

    1986-09-01

    Optical emission spectra from high-purity Pu-242 were generated with a glovebox-enclosed inductively coupled plasma (ICP) source. Spectra covering the 2280 to 7008 Angstrom wavelength range are presented along with general commentary on ICP-Pu spectroscopy.

  3. FPGA-based entropy neural processor for online detection of multiple combined faults on induction motors

    NASA Astrophysics Data System (ADS)

    Cabal-Yepez, E.; Valtierra-Rodriguez, M.; Romero-Troncoso, R. J.; Garcia-Perez, A.; Osornio-Rios, R. A.; Miranda-Vidales, H.; Alvarez-Salas, R.

    2012-07-01

    For industry, a faulty induction motor signifies production reduction and cost increase. Real-world induction motors can have one or more faults present at the same time that can mislead to a wrong decision about its operational condition. The detection of multiple combined faults is a demanding task, difficult to accomplish even with computing intensive techniques. This work introduces information entropy and artificial neural networks for detecting multiple combined faults by analyzing the 3-axis startup vibration signals of the rotating machine. A field programmable gate array implementation is developed for automatic online detection of single and combined faults in real time.

  4. Mathematical modeling of intrinsic Josephson junctions with capacitive and inductive couplings

    NASA Astrophysics Data System (ADS)

    Rahmonov, I. R.; Shukrinov, Yu M.; Zemlyanaya, E. V.; Sarhadov, I.; Andreeva, O.

    2012-11-01

    We investigate the current voltage characteristics (CVC) of intrinsic Josephson junctions (IJJ) with two types of couplings between junctions: capacitive and inductive. The IJJ model is described by a system of coupled sine-Gordon equations which is solved numerically by the 4th order Runge-Kutta method. The method of numerical simulation and numerical results are presented. The magnetic field distribution is calculated as the function of coordinate and time at different values of the bias current. The influence of model parameters on the CVC is studied. The behavior of the IJJ in dependence on coupling parameters is discussed.

  5. Deposition Of Materials Using A Simple Planar Coil Radio Frequency Inductively Coupled Plasma System

    SciTech Connect

    Ng, K. H.; Wong, C. S.; Yap, S. L.; Gan, S. N.

    2009-07-07

    A planar coil RF inductively coupled plasma (PC-RFICP) systems is set up for the purpose of thin film deposition. The system is powered by a 13.56 MHz, 550 W, 50 OMEGA RF generator. The RF power is transferred to the plasma via a planar induction coil. The impedance matching unit consists of an air core step-down transformer and a tunable vacuum capacitor. This system is used for the plasma enhanced chemical vapor deposition (PECVD) of diamond-like carbon (DLC) film on silicon substrate, and hydrogenated amorphous carbon (a-C:H) film.

  6. Unstart coupling mechanism analysis of multiple-modules hypersonic inlet.

    PubMed

    Hu, Jichao; Chang, Juntao; Wang, Lei; Cao, Shibin; Bao, Wen

    2013-01-01

    The combination of multiplemodules in parallel manner is an important way to achieve the much higher thrust of scramjet engine. For the multiple-modules scramjet engine, when inlet unstarted oscillatory flow appears in a single-module engine due to high backpressure, how to interact with each module by massflow spillage, and whether inlet unstart occurs in other modules are important issues. The unstarted flowfield and coupling characteristic for a three-module hypersonic inlet caused by center module II and side module III were, conducted respectively. The results indicate that the other two hypersonic inlets are forced into unstarted flow when unstarted phenomenon appears on a single-module hypersonic inlet due to high backpressure, and the reversed flow in the isolator dominates the formation, expansion, shrinkage, and disappearance of the vortexes, and thus, it is the major factor of unstart coupling of multiple-modules hypersonic inlet. The coupling effect among multiple modules makes hypersonic inlet be more likely unstarted. PMID:24348146

  7. Unstart Coupling Mechanism Analysis of Multiple-Modules Hypersonic Inlet

    PubMed Central

    Wang, Lei; Cao, Shibin

    2013-01-01

    The combination of multiplemodules in parallel manner is an important way to achieve the much higher thrust of scramjet engine. For the multiple-modules scramjet engine, when inlet unstarted oscillatory flow appears in a single-module engine due to high backpressure, how to interact with each module by massflow spillage, and whether inlet unstart occurs in other modules are important issues. The unstarted flowfield and coupling characteristic for a three-module hypersonic inlet caused by center module II and side module III were, conducted respectively. The results indicate that the other two hypersonic inlets are forced into unstarted flow when unstarted phenomenon appears on a single-module hypersonic inlet due to high backpressure, and the reversed flow in the isolator dominates the formation, expansion, shrinkage, and disappearance of the vortexes, and thus, it is the major factor of unstart coupling of multiple-modules hypersonic inlet. The coupling effect among multiple modules makes hypersonic inlet be more likely unstarted. PMID:24348146

  8. Study of the effect of loop inductance on the RF transmission line to cavity coupling coefficient.

    PubMed

    Lal, Shankar; Pant, K K

    2016-08-01

    Coupling of RF power is an important aspect in the design and development of RF accelerating structures. RF power coupling employing coupler loops has the advantage of tunability of β, the transmission line to cavity coupling coefficient. Analytical expressions available in literature for determination of size of the coupler loop using Faraday's law of induction show reasonably good agreement with experimentally measured values of β below critical coupling (β ≤ 1) but show large deviation with experimentally measured values and predictions by simulations for higher values of β. In actual accelerator application, many RF cavities need to be over-coupled with β > 1 for reasons of beam loading compensation, reduction of cavity filling time, etc. This paper discusses a modified analytical formulation by including the effect of loop inductance in the determination of loop size for any desired coupling coefficient. The analytical formulation shows good agreement with 3D simulations and with experimentally measured values. It has been successfully qualified by the design and development of power coupler loops for two 476 MHz pre-buncher RF cavities, which have successfully been conditioned at rated power levels using these coupler loops. PMID:27587114

  9. Laser sampling system for an inductively-coupled atomic emission spectrometer. Final report

    SciTech Connect

    1998-02-15

    A laser sampling system was attached to a Perkin Elmer Optima 3000 inductively-coupled plasma, atomic emission spectrometer that was already installed and operating in the Chemistry and Geochemistry Department at the Colorado School of Mines. The use of the spectrometer has been highly successful. Graduate students and faculty from at least four different departments across the CSM campus have used the instrument. The final report to NSF is appended to this final report. Appendices are included which summarize several projects utilizing this instrument: acquisition of an inductively-coupled plasma atomic emission spectrometer for the geochemistry program; hydrogen damage susceptibility assessment for high strength steel weldments through advanced hydrogen content analysis, 1996 and 1997 annual reports; and methods for determination of hydrogen distribution in high strength steel welds.

  10. Effect of Antenna Diameter on the Characteristics of Internal-Type Linear Inductively Coupled Plasma

    NASA Astrophysics Data System (ADS)

    Hyeuk Lim, Jong; Kim, Kyong Nam; Gweon, Gwang Ho; Hong, Seung Pyo; Yeom, Geun Young

    2009-09-01

    In this study, the antenna characteristics of an internal-type, linear, inductively coupled plasma (ICP) source were varied by changing the inner conductor diameter of the ICP antenna composed of an inner conductor enclosed by outer dielectric tubing. The effect of the varied antenna characteristics on the plasma characteristics and the electrical characteristics of the large area plasma source with a substrate area of 2300×2000 mm2 were investigated. The decrease of the antenna conductor diameter from 25 to 10 mm decreased the capacitance of the antenna between the conductor and the dielectric tubing, increased the plasma density, decreased the plasma potential at the same rf power, and improved the plasma uniformity. The increased plasma density and the decreased plasma potential obtained with the smaller antenna conductor diameter were attributed to the increased power transfer efficiency caused by the increased inductive coupling at the same rf power.

  11. Effect of antenna capacitance on the plasma characteristics of an internal linear inductively coupled plasma system

    NASA Astrophysics Data System (ADS)

    Lim, Jong Hyeuk; Kim, Kyong Nam; Park, Jung Kyun; Yeom, Geun Young

    2008-08-01

    This study examined the effect of the antenna capacitance of an inductively coupled plasma (ICP) source, which was varied using an internal linear antenna, on the electrical and plasma characteristics of the ICP source. The inductive coupling at a given rf current increased with decreasing antenna capacitance. This was caused by a decrease in the inner copper diameter of the antenna made from coaxial copper/quartz tubing, which resulted in a higher plasma density and lower plasma potential. By decreasing the diameter of the copper tube from 25to10mm, the plasma density of a plasma source size of 2750×2350mm2 was increased from approximately 8×1010/cm3to1.5×1011/cm3 at 15mTorr Ar and 9kW of rf power.

  12. Effect of Antenna Diameter on the Characteristics of Internal-Type Linear Inductively Coupled Plasma

    NASA Astrophysics Data System (ADS)

    Lim, Jong Hyeuk; Kim, Kyong Nam; Gweon, Gwang Ho; Hong, Seung Pyo; Yeom, Geun Young

    2009-09-01

    In this study, the antenna characteristics of an internal-type, linear, inductively coupled plasma (ICP) source were varied by changing the inner conductor diameter of the ICP antenna composed of an inner conductor enclosed by outer dielectric tubing. The effect of the varied antenna characteristics on the plasma characteristics and the electrical characteristics of the large area plasma source with a substrate area of 2300× 2000 mm2 were investigated. The decrease of the antenna conductor diameter from 25 to 10 mm decreased the capacitance of the antenna between the conductor and the dielectric tubing, increased the plasma density, decreased the plasma potential at the same rf power, and improved the plasma uniformity. The increased plasma density and the decreased plasma potential obtained with the smaller antenna conductor diameter were attributed to the increased power transfer efficiency caused by the increased inductive coupling at the same rf power.

  13. Study on spatial distribution of plasma parameters in a magnetized inductively coupled plasma

    SciTech Connect

    Cheong, Hee-Woon; Lee, Woohyun; Kim, Ji-Won; Whang, Ki-Woong; Kim, Hyuk; Park, Wanjae

    2015-07-15

    Spatial distributions of various plasma parameters such as plasma density, electron temperature, and radical density in an inductively coupled plasma (ICP) and a magnetized inductively coupled plasma (M-ICP) were investigated and compared. Electron temperature in between the rf window and the substrate holder of M-ICP was higher than that of ICP, whereas the one just above the substrate holder of M-ICP was similar to that of ICP when a weak (<8 G) magnetic field was employed. As a result, radical densities in M-ICP were higher than those in ICP and the etch rate of oxide in M-ICP was faster than that in ICP without severe electron charging in 90 nm high aspect ratio contact hole etch.

  14. Boron determination in steels by Inductively-Coupled Plasma spectometry (ICP)

    NASA Technical Reports Server (NTRS)

    Coedo, A. G.; Lopez, M. T. D.

    1986-01-01

    The sample is treated with 5N H2SO4 followed by concentrated HNO3 and the diluted mixture is filtered. Soluble B is determined in the filtrate by Inductively-Coupled Plasma (ICP) spectrometry after addition HCl and extraction of Fe with ethyl-ether. The residue is fused with Na2CO3 and, after treatment with HCl, the insoluble B is determined by ICP spectrometry as before. The method permits determination of ppm amounts of B in steel.

  15. Modelling of an inductively coupled plasma torch with argon at atmospheric pressure

    NASA Astrophysics Data System (ADS)

    Bahouh, Hanene; Rebiai, Saida; Rochette, David; Vacher, Damien; Dudeck, Michel

    2014-05-01

    A fluid dynamic model is used to simulate the electromagnetic field, fluid flow and heat transfer in an inductively coupled plasma torch working at atmospheric pressure for argon plasma. The numerical simulation is carried out by using the finite element method based on COMSOL software. The two-dimensional profiles of the electric field, temperature, velocity and charged particle densities are demonstrated inside the discharge region. These numerical results are obtained for a fixed flow rate, frequency and electric power.

  16. In situ calibration of inductively coupled plasma-atomic emission and mass spectroscopy

    DOEpatents

    Braymen, S.D.

    1996-06-11

    A method and apparatus are disclosed for in situ addition calibration of an inductively coupled plasma atomic emission spectrometer or mass spectrometer using a precision gas metering valve to introduce a volatile calibration gas of an element of interest directly into an aerosol particle stream. The present in situ calibration technique is suitable for various remote, on-site sampling systems such as laser ablation or nebulization. 5 figs.

  17. Quantum Fluctuations of Mesoscopic Damped Circuit Involving Capacitance-Inductance Coupling at a Finite Temperature

    NASA Astrophysics Data System (ADS)

    Xu, Xing-Lei; Xu, Shi-Min; Li, Hong-Qi

    2008-06-01

    The quantization of mesoscopic damped circuit involving capacitance-inductance coupling is proposed by the method of thrice linear transformation and damped harmonic oscillator quantization. The quantum fluctuations of the charges and current of each loop are calculated by thermo-field dynamics (TFD) in thermal vacuum state, thermal coherent state and thermal squeezed state, respectively. It is shown that the quantum fluctuations of the charges and current not only depend on circuit inherent parameter and coupled magnitude, but also rely on squeezed coefficients, squeezed angle, environmental temperature and damped resistance. And, because of influence of environmental temperature and damped resistance, the quantum fluctuations increase with increasing temperature and decrease with prolonging time.

  18. Rigorous design of matched wireless power transfer links based on inductive coupling

    NASA Astrophysics Data System (ADS)

    Monti, G.; Costanzo, A.; Mastri, F.; Mongiardo, M.; Tarricone, L.

    2016-06-01

    This paper focuses on a near-field wireless power transmission link consisting of two magnetically coupled inductances. The case of a resonant coupling realized by adding appropriate compensating capacitances is solved. By using a network formalism, the link is modeled as a two-port network and rigorously analyzed in the case where both the input impedance and the load are specified. In particular, it is demonstrated that there is just one optimum design of the network that allows maximizing both the efficiency and the active power on the load. Closed-form design formulas for the optimum design are presented and validated by circuital simulations.

  19. Thermochemical Nonequilibrium 2D Modeling of Nitrogen Inductively Coupled Plasma Flow

    NASA Astrophysics Data System (ADS)

    Yu, Minghao; Yusuke, Takahashi; Hisashi, Kihara; Ken-ichi, Abe; Kazuhiko, Yamada; Takashi, Abe; Satoshi, Miyatani

    2015-09-01

    Two-dimensional (2D) numerical simulations of thermochemical nonequilibrium inductively coupled plasma (ICP) flows inside a 10-kW inductively coupled plasma wind tunnel (ICPWT) were carried out with nitrogen as the working gas. Compressible axisymmetric Navier-Stokes (N-S) equations coupled with magnetic vector potential equations were solved. A four-temperature model including an improved electron-vibration relaxation time was used to model the internal energy exchange between electron and heavy particles. The third-order accuracy electron transport properties (3rd AETP) were applied to the simulations. A hybrid chemical kinetic model was adopted to model the chemical nonequilibrium process. The flow characteristics such as thermal nonequilibrium, inductive discharge, effects of Lorentz force were made clear through the present study. It was clarified that the thermal nonequilibrium model played an important role in properly predicting the temperature field. The prediction accuracy can be improved by applying the 3rd AETP to the simulation for this ICPWT. supported by Grant-in-Aid for Scientific Research (No. 23560954), sponsored by the Japan Society for the Promotion of Science

  20. Coherent coupling of multiple transverse modes in quantum cascade lasers.

    PubMed

    Yu, Nanfang; Diehl, Laurent; Cubukcu, Ertugrul; Bour, David; Corzine, Scott; Höfler, Gloria; Wojcik, Aleksander K; Crozier, Kenneth B; Belyanin, Alexey; Capasso, Federico

    2009-01-01

    Quantum cascade lasers are a unique laboratory for studying nonlinear laser dynamics because of their high intracavity intensity, strong intersubband optical nonlinearity, and an unusual combination of relaxation time scales. Here we investigate the nonlinear coupling between the transverse modes of quantum cascade lasers. We present evidence for stable phase coherence of multiple transverse modes over a large range of injection currents. We explain the phase coherence by a four-wave mixing interaction originating from the strong optical nonlinearity of the gain transition. The phase-locking conditions predicted by theory are supported by spectral data and both near- and far-field mode measurements. PMID:19257192

  1. Complex image method for RF antenna-plasma inductive coupling calculation in planar geometry. Part I: basic concepts

    NASA Astrophysics Data System (ADS)

    Howling, A. A.; Guittienne, Ph; Jacquier, R.; Furno, I.

    2015-12-01

    The coupling between an inductive source and the plasma determines the power transfer efficiency and the reflected impedance in the primary circuit. Usually, the plasma coupling is analysed by means of a transformer equivalent circuit, where the plasma inductance and resistance are estimated using a global plasma model. This paper shows that, for planar RF antennas, the mutual inductance between the plasma and the primary circuit can be calculated using partial inductances and the complex image method, where the plasma coupling is determined in terms of the plasma skin depth and the distance to the plasma. To introduce the basic concepts, the mutual inductance is calculated here for a linear conductor parallel to the plasma surface. In the accompanying paper part II Guittienne et al (2015 Plasma Sources Sci. Technol. 24 065015), impedance measurements on a RF resonant planar plasma source are modeled using an impedance matrix where the plasma-antenna mutual impedances are calculated using the complex image method presented here.

  2. Development and characterization of induction heating electrothermal vaporization (IH-ETV) sample introduction for inductively coupled plasma spectrometry

    NASA Astrophysics Data System (ADS)

    Rybak, Michael E.; Salin, Eric D.

    2001-03-01

    A general study of performance attributes was conducted for a prototypical electrothermal vaporization (ETV) sample introduction system, in which induction heating (IH) was used to facilitate the drying, pyrolysis, and vaporization of samples from long, undercut graphite cup probes in a radio-frequency (RF) induction field. In the first part of this study, experiments were carried out to determine the heating characteristics and temperature control aspects of an IH-ETV arrangement. Using a remote-sensing infrared thermocouple, it was determined that a 3/8-inch (9.53-mm) outer diameter graphite cup sample probe could be heated to a maximum temperature of 1860°C in the induction field of the IH-ETV under full forward power (1.5 kW). The IH-ETV device was found to have a rapid heating response (1/ e time-constant of 2.0±0.2 s) that was independent of the initial/final temperatures chosen. Linear temperature control was possible by regulating either the DC voltage applied to the plate or the current flowing to the grid of the RF generator oscillator tube. The second part of this work consisted of studies to establish benchmarks, such as limits of detection (LOD) with inductively coupled plasma optical emission spectrometry (ICP-OES) and transport efficiency for analyte vaporization under several x-Ar mixed gas atmospheres [where x=15% N 2, 10% O 2, HCl (sparged), or 15% SF 6 (v/v)]. In general, reproducible transient signals with evolution times of 5-15 s were seen for the vaporization of most elements studied, with peak area intensity and reproducibility generally being the best with SF 6-Ar. A 10-fold increase in transport efficiency was seen for refractory carbide-forming analytes (Cr, V) when vaporization was conducted in a halogenous ( x=HCl, SF 6) versus non-halogenous ( x=N 2, O 2) environment, with a two-fold improvement being observed for most other non-refractory elements (Cd, Cu, Fe, Mn, Ni, Pb, Zn). The transport of arsenic proved to be a special case

  3. Equivalent circuit effects on mode transitions in H{sub 2} inductively coupled plasmas

    SciTech Connect

    Xu, Hui-Jing; Zhao, Shu-Xia Zhang, Yu-Ru; Gao, Fei; Li, Xue-Chun; Wang, You-Nian

    2015-04-15

    It is well known experimentally that the circuit matching network plays an important role in the mode transition behavior of inductively coupled plasmas. To date, however, there have been no reports of numerical models being used to study the role of the matching circuit in the transition process. In this paper, a new two-dimensional self-consistent fluid model that couples the components of an equivalent circuit module is developed to investigate the effects of the equivalent circuit on the mode transition characteristics of an inductively coupled, hydrogen plasma. The equivalent circuit consists of a current source, impedance matching network, reactor impedance, and plasma transferred impedance. The nonlinear coupling of the external circuit with the internal plasma is investigated by adjusting the matching capacitance at a fixed input current. The electron density and temperature as well as the electromagnetic fields all change suddenly, and the E to H mode transition occurs abruptly at a certain matching capacitance as the impedance matching of the external circuit is varied. We also analyze the fields and the plasma characteristics during the transition process, especially for the case of the capacitive E mode.

  4. EVALUATION OF A MULTICHANNEL INDUCTIVELY COUPLED PLASMA-OPTICAL EMISSION SPECTROMETER MODIFIED TO MINIMIZE AND CORRECT SCATTERED LIGHT EFFECTS

    EPA Science Inventory

    In a study of an inductively coupled plasma optical emission spectrometer, data from an early commercially available instrument are compared with data from the same instrument after modifications to correct observed inadequacies were made. Results show negligible changes in power...

  5. Symmetric Absorber-Coupled Far-Infrared Microwave Kinetic Inductance Detector

    NASA Technical Reports Server (NTRS)

    U-yen, Kongpop (Inventor); Wollack, Edward J. (Inventor); Brown, Ari D. (Inventor); Stevenson, Thomas R. (Inventor); Patel, Amil A. (Inventor)

    2016-01-01

    The present invention relates to a symmetric absorber-coupled far-infrared microwave kinetic inductance detector including: a membrane having an absorber disposed thereon in a symmetric cross bar pattern; and a microstrip including a plurality of conductor microstrip lines disposed along all edges of the membrane, and separated from a ground plane by the membrane. The conducting microstrip lines are made from niobium, and the pattern is made from a superconducting material with a transition temperature below niobium, including one of aluminum, titanium nitride, or molybdenum nitride. The pattern is disposed on both a top and a bottom of the membrane, and creates a parallel-plate coupled transmission line on the membrane that acts as a half-wavelength resonator at readout frequencies. The parallel-plate coupled transmission line and the conductor microstrip lines form a stepped impedance resonator. The pattern provides identical power absorption for both horizontal and vertical polarization signals.

  6. Thin-layer chromatography combined with diode laser thermal vaporization inductively coupled plasma mass spectrometry.

    PubMed

    Bednařík, Antonín; Tomalová, Iva; Kanický, Viktor; Preisler, Jan

    2014-10-17

    Here we present a novel coupling of thin-layer chromatography (TLC) to diode laser thermal vaporization inductively coupled plasma mass spectrometry (DLTV ICP MS). DLTV is a new technique of aerosol generation which uses a diode laser to induce pyrolysis of a substrate. In this case the cellulose stationary phase on aluminum-backed TLC sheets overprinted with black ink to absorb laser light. The experimental arrangement relies on economic instrumentation: an 808-nm 1.2-W continuous-wave infrared diode laser attached to a syringe pump serving as the movable stage. Using a glass tubular cell, the entire length of a TLC separation channel is scanned. The 8-cm long lanes were scanned in ∼35 s. The TLC - DLTV ICP MS coupling is demonstrated on the separation of four cobalamins (hydroxo-; adenosyl-; cyano-; and methylcobalamin) with limits of detection ∼2 pg and repeatability ∼15% for each individual species. PMID:25193171

  7. Remote electronic control of DNA hybridization through inductive coupling to an attached metal nanocrystal antenna

    NASA Astrophysics Data System (ADS)

    Hamad-Schifferli, Kimberly; Schwartz, John J.; Santos, Aaron T.; Zhang, Shuguang; Jacobson, Joseph M.

    2002-01-01

    Increasingly detailed structural and dynamic studies are highlighting the precision with which biomolecules execute often complex tasks at the molecular scale. The efficiency and versatility of these processes have inspired many attempts to mimic or harness them. To date, biomolecules have been used to perform computational operations and actuation, to construct artificial transcriptional loops that behave like simple circuit elements and to direct the assembly of nanocrystals. Further development of these approaches requires new tools for the physical and chemical manipulation of biological systems. Biomolecular activity has been triggered optically through the use of chromophores, but direct electronic control over biomolecular `machinery' in a specific and fully reversible manner has not yet been achieved. Here we demonstrate remote electronic control over the hybridization behaviour of DNA molecules, by inductive coupling of a radio-frequency magnetic field to a metal nanocrystal covalently linked to DNA. Inductive coupling to the nanocrystal increases the local temperature of the bound DNA, thereby inducing denaturation while leaving surrounding molecules relatively unaffected. Moreover, because dissolved biomolecules dissipate heat in less than 50picoseconds (ref. 16), the switching is fully reversible. Inductive heating of macroscopic samples is widely used, but the present approach should allow extension of this concept to the control of hybridization and thus of a broad range of biological functions on the molecular scale.

  8. Effect of coupling currents on the dynamic inductance during fast transient in superconducting magnets

    NASA Astrophysics Data System (ADS)

    Marinozzi, V.; Sorbi, M.; Manfreda, G.; Bellina, F.; Bajas, H.; Chlachidze, G.

    2015-03-01

    We present electromagnetic models aiming to calculate the variation of the inductance in a magnet due to dynamic effects such as the variation of magnetization or the coupling with eddy currents. The models are studied with special regard to the calculation of the inductance in superconducting magnets which are affected by interfilament coupling currents. The developed models have been compared with experimental data coming from tests of prototype Nb3Sn magnets designed for the new generation of accelerators. This work is relevant for the quench protection study of superconducting magnets: quench is an unwanted event, when part of the magnet becomes resistive; in these cases, the current should be discharged as fast as possible, in order to maintain the resistive zone temperature under a safe limit. The magnet inductance is therefore a relevant term for the description of the current discharge, especially for the high-field new generation superconducting magnets for accelerators, and this work shows how to calculate the correct value during rapid current changes, providing a mean for simulations of the reached temperature.

  9. [Impact of TDZ and NAA on adventitious bud induction and cluster bud multiplication in Tulipa edulis].

    PubMed

    Zhu, Li-Fang; Xu, Chao; Zhu, Zai-Biao; Yang, He-Tong; Guo, Qiao-Sheng; Xu, Hong-jian; Ma, Hong-Jian; Zhao, Gui-Hua

    2014-08-01

    To explore the method of explants directly induced bud and establish the tissue culture system of mutiple shoot by means of direct organogenesis, core bud and daughter bulbs (the top of bud stem expanded to form daughter bulb) of T. edulis were used as explants and treated with thidiazuron (TDZ) and 1-naphthlcetic acid (NAA). The results showed that the optimal medium for bud inducted form core bud and daughter bulb were MS + TDZ 2.0 mg x L(-1) + NAA 4.0 mg x L(-1) and MS +TDZ 2.0 mg x L(-1) + NAA 2.0 mg x L(-1) respectively, both of them had a bud induction rate of 72.92%, 79.22%. The optimal medium for cluster buds multiplication was MS + TDZ 0.2 mg x L(-1) + NAA 0.2 mg x L(-1), and proliferation coefficient was 2.23. After proliferation, cluster buds rooting occurred on MS medium with IBA 1.0 mg x L(-1) and the rooting rate was 52.6%, three to five seedlings in each plant. Using core bud and daughter bulb of T. edulis, the optimum medium for adventitious bud directly inducted from daughter bulb, core bud and cluster bud multiplication were screened out and the tissue culture system of multiple shoot by means of direct organogenesis was established. PMID:25509282

  10. Dengue 2 infection of HepG2 liver cells results in endoplasmic reticulum stress and induction of multiple pathways of cell death

    PubMed Central

    2013-01-01

    Background A number of studies have implicated the direct involvement of the liver in dengue virus (DENV) infection, and it has been widely shown that liver cells subsequently undergo apoptosis. The mechanism by which liver cells undergo apoptosis in response to DENV infection remains unclear. To provide further information on the mechanism of apoptosis in DENV infected liver cells, HepG2 cells were infected with DENV 2 and analyzed for the induction of ER stress, apoptosis and autophagy. Results In response to DENV infection, HepG2 cells showed the induction of both the ER resident unfolded protein response as well as the Noxa/PUMA stress response pathways. Proteolytic activation of caspases 4, 7, 8 and 9 was observed as well as changes in mitochondrial transmembrane potential. Increased monodansylcadaverine staining was observed in DENV infected cells, consistent with the previously reported induction of autophagy. Conclusions These results are consistent with a model in which the induction of multiple ER stress pathways is coupled with the induction of multiple cell death pathways as a mechanism to ensure the removal of infected liver cells from the system. PMID:24034452

  11. Multiple steady states in coupled flow tank reactors

    NASA Astrophysics Data System (ADS)

    Hunt, Katharine L. C.; Kottalam, J.; Hatlee, Michael D.; Ross, John

    1992-05-01

    Coupling between continuous-flow, stirred tank reactors (CSTR's), each having multiple steady states, can produce new steady states with different concentrations of the chemical species in each of the coupled tanks. In this work, we identify a kinetic potential ψ that governs the deterministic time evolution of coupled tank reactors, when the reaction mechanism permits a single-variable description of the states of the individual tanks; examples include the iodate-arsenous acid reaction, a cubic model suggested by Noyes, and two quintic models. Stable steady states correspond to minima of ψ, and unstable steady states to maxima or saddle points; marginally stable states typically correspond to saddle-node points. We illustrate the variation in ψ due to changes in the rate constant for external material intake (k0) and for exchange between tanks (kx). For fixed k0 values, we analyze the changes in numbers and types of steady states as kx increases from zero. We show that steady states disappear by pairwise coalescence; we also show that new steady states may appear with increasing kx, when the reaction mechanism is sufficiently complex. For fixed initial conditions, the steady state ultimately reached in a mixing experiment may depend on the exchange rate constant as a function of time, kx(t) : Adiabatic mixing is obtained in the limit of slow changes in kx(t) and instantaneous mixing in the limit as kx(t)→∞ while t remains small. Analyses based on the potential ψ predict the outcome of mixing experiments for arbitrary kx(t). We show by explicit counterexamples that a prior theory developed by Noyes does not correctly predict the instability points or the transitions between steady states of coupled tanks, to be expected in mixing experiments. We further show that the outcome of such experiments is not connected to the relative stability of steady states in individual tank reactors. We find that coupling may effectively stabilize the tanks. We provide

  12. Ion Flux and Ion Energy Distributions in an Inductively Coupled GEC Rf Refererence Cell in Chlorine

    NASA Astrophysics Data System (ADS)

    Radovanov, Svetlana; Forrister, Ray; Anderson, Harold

    1996-10-01

    Ion flux and energy distribution measurements in pure chlorine were performed in an inductively coupled Gaseous Electronics Reference Cell 13.56 MHz radiofrequency discharge . Measurements were made using miniaturized gridded energy analyzer. This detector was developed at the University of New Mexico, based on earlier design of the small size energy analyzers at MIT. The detector was mounted on a 12 inch water cooled carrier to suppress probe heating. The probe could be radially moved in the discharge cell to monitor the radial uniformity of the plasma. In addition, the detector was protected with a ceramic coating to supress for the electron saturation current of unshielded probe areas. The measurements were done in the "bright " mode dominated by inductive coupling at different pressures and powers. The radial variation of the ion flux in pure chlorine and argon show similar strongly nonuniform profile. As expected, absolute ion flux values in chlorine are substantially decreased compared to pure argon discharge. The spatial nonuniformity across the 16 cm diameter surface of the grounded electrode is in agreement with the Langmuir probe measurements done by Miller and MIT measurements in pure argon. The ion energy distribution functions (IEDs) measured exhibit a complex structure indicative of both light Cl^+ and heavier Cl_2^+ ions. The IEDs in chlorine are much broder than those measured in pure argon plasma. The radial profile of IEDs found in the GEC/ICP chlorine discharge indicate large changes are occuring in the nature of power coupling to the discharge moving center to edge.

  13. 3D-PIC simulation of an inductively coupled ion source

    NASA Astrophysics Data System (ADS)

    Henrich, Robert; Muehlich, Nina Sarah; Becker, Michael; Heiliger, Christian

    2015-09-01

    Inductively coupled ion sources are applied to a wide range of plasma applications, especially surface modifications. The knowledge of the behavior and precise information of the plasma parameters are of main importance. These values are tedious to measure without influencing the discharge. By applying our fully three-dimensional PlasmaPIC tool we are able to reach these plasma parameters with a spatial and temporal resolution which is quite hard to achieve experimentally. PlasmaPIC is used for modeling discharges in arbitrary geometries without limitations to any symmetry. By this means we are able to demonstrate that the plasma density has an irrotational character. Furthermore, we will show the dependence of the plasma parameters of different working conditions. We will show that for gridded inductively coupled ion sources the neutral gas pressure inside the discharge chamber depends on the extraction of ions. This effect is considered in PlasmaPIC by a self-consistent coupling of the neutral gas simulation and the plasma simulation whereas the neutral gas distribution is calculated using the direct simulation Monte Carlo method (DSMC). This work has been supported by the ``Bundesministerium fuer Wirtschaft und Energie.'' Grant 50RS1507.

  14. Multiple climate and sea ice states on a coupled Aquaplanet

    NASA Astrophysics Data System (ADS)

    Rose, B.; Ferreira, D.; Marshall, J.

    2010-12-01

    A fully coupled atmosphere-ocean-sea ice GCM is used to explore the climates of Earth-like planets with no continents and idealized ocean basin geometries. We find three qualitatively different stable equilibria under identical external forcing: an equable ice-free climate, a cold climate with ice caps extending into mid-latitudes, and a completely ice-covered "Snowball" state. These multiple states persist for millennia with no drift despite a full seasonal cycle and vigorous internal variability of the system on all time scales. The behavior of the coupled system is rationalized through an extension of the Budyko-Sellers model to include explicit ocean heat transport (OHT), and the insulation of the ice-covered sea surface. Sensitivity tests are also conducted with a slab ocean GCM with prescribed OHT. From these we conclude that albedo feedback and ocean circulation both play essential roles in the maintenance of the multiple states. OHT in the coupled system is dominated by a wind-driven subtropical cell carrying between 2 and 3 PW of thermal energy out of the deep tropics, most of which converges in the subtropics to lower mid-latitudes. This convergence pattern (similar to modern Earth) is robust to changes in the ocean basin geometry, and is directly responsible for the stabilization of the large ice cap. OHT also plays an essential but indirect role in the maintenance of the ice-free pole in the warm states, by driving an enhanced poleward atmospheric latent heat flux. The hysteresis loop for transitions between the warm and large ice cap states spans a much smaller range of parameter space (e.g. ±1.8% variations in solar constant) than the transitions in and out of the Snowball. Three qualitatively different climate states for the same external forcing in a coupled GCM: ice-free, large ice cap, and Snowball. SST and sea ice thickness are plotted. Similar results are found in a pure Aquaplanet (lower) and a "RidgeWorld" with a global-scale ocean basin

  15. Online Coupling of Flow-Field Flow Fractionation and Single Particle Inductively Coupled Plasma-Mass Spectrometry: Characterization of Nanoparticle Surface Coating Thickness and Aggregation State

    EPA Science Inventory

    Surface coating thickness and aggregation state have strong influence on the environmental fate, transport, and toxicity of engineered nanomaterials. In this study, flow-field flow fractionation coupled on-line with single particle inductively coupled plasma-mass spectrometry i...

  16. Inductively coupled plasma mass spectrometry for stable isotope metabolic tracer studies of living systems

    SciTech Connect

    Luong, E.

    1999-05-10

    This dissertation focuses on the development of methods for stable isotope metabolic tracer studies in living systems using inductively coupled plasma single and dual quadrupole mass spectrometers. Sub-nanogram per gram levels of molybdenum (Mo) from human blood plasma are isolated by the use of anion exchange alumina microcolumns. Million-fold more concentrated spectral and matrix interferences such as sodium, chloride, sulfate, phosphate, etc. in the blood constituents are removed from the analyte. The recovery of Mo from the alumina column is 82 {+-} 5% (n = 5). Isotope dilution inductively coupled plasma mass spectrometry (ID-ICP-MS) is utilized for the quantitative ultra-trace concentration determination of Mo in bovine and human blood samples. The average Mo concentration in reference bovine serum determined by this method is 10.2 {+-} 0.4 ng/g, while the certified value is 11.5 {+-} 1.1 ng/g (95% confidence interval). The Mo concentration of one pool of human blood plasma from two healthy male donors is 0.5 {+-} 0.1 ng/g. The inductively coupled plasma twin quadrupole mass spectrometer (ICP-TQMS) is used to measure the carbon isotope ratio from non-volatile organic compounds and bio-organic molecules to assess the ability as an alternative analytical method to gas chromatography combustion isotope ratio mass spectrometry (GC-combustion-IRMS). Trytophan, myoglobin, and {beta}-cyclodextrin are chosen for the study, initial observation of spectral interference of {sup 13}C{sup +} with {sup 12}C{sup 1}H{sup +} comes from the incomplete dissociation of myoglobin and/or {beta}-cyclodextrin.

  17. Chemical recoveries of technetium-99 for various procedures using inductively coupled plasma-mass spectrometry

    SciTech Connect

    Ihsanullah; East, B.W.

    1993-12-31

    The procedure for the determination of {sup 99}Tc inductively coupled plasma-mass spectrometry (ICP-MS) was based on the modification of a variety of available separation techniques. Standard Ru and Rh solutions were used for checking decontaminations and instrument response respectively. Technetium-99 and {sup 95m}Tc tracers were applied as yield monitors using ICP-MS and gamma-ray spectrometry respectively. Percent recoveries are reported for a variety of radiochemical separation procedures for water (58-83%), seaweed (10-76%), and for soil matrices (19-79%).

  18. Carboxymethylated polyethylenimine-polymethylenepolyphenylene isocyanate chelating ion exchange resin preconcentration for inductively coupled plasma spectrometry

    SciTech Connect

    Horvath, A.; Barnes, R.M.

    1986-06-01

    A carboxymethylated polyethylenimine-polylmethylenepolyphenylene isocyanate chelating ion exchange resin was prepared, characterized, and used for metals preconcentration for inductively coupled plasma spectrometry. The uptake of copper, cadmium, lead, and zinc by the resin was quantitative in the presence of high concentrations of ammonium, calcium, magnesium, potassium, sodium, and acetate and citrate salts. These metals could be collected from artificial seawater, Dead Sea water, and dissolved bone with a recovery of nearly 100%. The resin also chelates heavy metals and rare earths. Complexed metals can be eluted from the resin column with strong acids. The resin does not change volume with ionic form changes and can be regenerated for repeated use.

  19. Parametric study of compound semiconductor etching utilizing inductively coupled plasma source

    SciTech Connect

    Constantine, C.; Johnson, D.; Barratt, C.

    1996-07-01

    Inductively Coupled Plasma (ICP) sources are extremely promising for large-area, high-ion density etching or deposition processes. In this review the authors compare results for GaAs and GaN etching with both ICP and Electron Cyclotron Resonance (ECR) sources on the same single-wafer platform. The ICP is shown to be capable of very high rates with excellent anisotropy for fabrication of GaAs vias or deep mesas in GaAs or GaN waveguide structures.

  20. Coupling of Waveguide and Resonator by Inductive and Capacitive Irises for EPR Spectroscopy

    PubMed Central

    Mett, R.R.; Sidabras, J.W.; Hyde, J.S.

    2009-01-01

    An analytic circuit model for slot coupling from a waveguide to a loop-gap resonator (LGR) in a context of electron paramagnetic resonance (EPR) spectroscopy is presented. The physical dimensions of the waveguide, iris, LGR, and aqueous sample are transformed into circuit values of inductance, capacitance, and resistance. These values are used in a solution of circuit equations that results in a prediction of the rf currents, magnitude and phase, frequency, and magnetic and electric stored energies near critical coupling. The circuit geometry reflects magnetic flux conservation between the iris and LGR as well as modification of the outer loop LGR currents by the iris. Unlike conventional models, coupling is not explicitly based on a mutual inductance between the iris and LGR. Instead, the conducting wall high frequency rf boundary condition is used to define surface currents, regions, and circuit topology with lumped-circuit values of self-inductance, capacitance, and resistance. Match is produced by a combination of self-inductive and capacitive circuit coupling. Two conditions must be met to achieve match. First, the equivalent resistance of the LGR as seen by the iris must be transformed into the waveguide characteristic impedance. This transformation is met at a particular frequency relative to the natural LGR resonance frequency. The frequency shift magnitude is largely determined by the LGR properties, weakly dependent on iris length and placement, and independent of other iris dimensions. The second condition for match is that the iris reactance at this frequency shift must cancel the residual reactance of the LGR. This second condition is sensitive to the iris dimensions. If both conditions are not simultaneously satisfied, overcoupling or undercoupling results. A slotted iris of equal length to the size of the large dimension of the waveguide is found to have many properties opposite to a conventional iris of shorter length. Notably, the magnetic field

  1. Evaluation of Inductively Couple Plasma-time-of-Flight Mass Spectrometry for Laser Ablation Analyses

    SciTech Connect

    S.J. Bajic; D.B. Aeschliman; D.P. Baldwin; R.S. Houk

    2003-09-30

    The purpose of this trip to LECO Corporation was to test the non-matrix matched calibration method and the principal component analysis (PCA) method on a laser ablation-inductively coupled plasma-time of flight mass spectrometry (LA-ICP-TOFMS) system. An LA-ICP-TOFMS system allows for multielement single-shot analysis as well as spatial analysis on small samples, because the TOFMS acquires an entire mass spectrum for all ions extracted simultaneously from the ICP. The TOFMS system differs from the double-focusing mass spectrometer, on which the above methods were developed, by having lower sensitivity and lower mass resolution.

  2. Nanoscale dry etching of germanium by using inductively coupled CF4 plasma

    NASA Astrophysics Data System (ADS)

    Shim, Kyu-Hwan; Yang, Ha Yong; Kil, Yeon-Ho; Yang, Hyeon Deok; Yang, Jong-Han; Hong, Woong-Ki; Kang, Sukill; Jeong, Tae Soo; Kim, Taek Sung

    2012-08-01

    The nanoscale dry etching of germanium was investigated by using inductively coupled CF4 plasma and electron-beam lithography. The optimal dose of PMMA as E-beam lithography resist was ˜200 mC/cm2. When ICP Power was 200W, CF4 gas flow rate was 40 sccm, and process pressure was 20 mTorr, it had a smooth surface and good etch rate. The etching selectivity of Ge wafer to PMMA resist was as low as ˜1.5. Various sub-100 nm dry-etching patterns have been obtained. SEM pictures showed good profile qualities with a smooth etching sidewall and ultrasmall etching features.

  3. Statistical evaluation of an inductively coupled plasma atomic emission spectrometric method for routine water quality testing

    USGS Publications Warehouse

    Garbarino, J.R.; Jones, B.E.; Stein, G.P.

    1985-01-01

    In an interlaboratory test, inductively coupled plasma atomic emission spectrometry (ICP-AES) was compared with flame atomic absorption spectrometry and molecular absorption spectrophotometry for the determination of 17 major and trace elements in 100 filtered natural water samples. No unacceptable biases were detected. The analysis precision of ICP-AES was found to be equal to or better than alternative methods. Known-addition recovery experiments demonstrated that the ICP-AES determinations are accurate to between plus or minus 2 and plus or minus 10 percent; four-fifths of the tests yielded average recoveries of 95-105 percent, with an average relative standard deviation of about 5 percent.

  4. Effects of coil location and injection flow rate in an inductively coupled RF plasma torch

    NASA Astrophysics Data System (ADS)

    Wei, D.; Apelian, D.; Farouk, B.

    1985-07-01

    A numerical model has been developed to investigate the effects of central carrier gas flow rate and coil location in an inductively coupled RF plasma torch. Solution algorithm is based on the primitive variable formulation of the Navier-Stokes equations and includes a pseudo two-dimensional electromagnetic field model. Computational results have shown that with increasing carrier gas flow rate, the plasma plume is penetrated and the back flow due to the magnetic pumping effects is diminished. This facilitates the delivery of powder particles into the discharge region. However, the plasma plume is also disturbed significantly thus enhancing power loss.

  5. Thomson scattering experiments on a 100 MHz inductively coupled plasma calibrated by Raman scattering

    SciTech Connect

    de Regt, J.M.; Engeln, R.A.H.; de Groote, F.P.J.; van der Mullen, J.A.M.; Schram, D.C.

    1995-05-01

    A new calibration method to obtain the electron density from Thomson scattering on an inductively coupled plasma is discussed. Raman scattering of nitrogen is used for recovering the Rayleigh scattering signal. This has the advantage that no corrections are necessary for stray light, like with other calibration methods, using the direct measured Rayleigh scattering signal on a well-known gas. It is shown that electron densities and electron temperatures can be measured with an accuracy of about 15% in density and of about 150 K in temperature. {copyright} {ital 1995} {ital American} {ital Institute} {ital of} {ital Physics}.

  6. Surface Modification of Nanometre Silicon Carbide Powder with Polystyrene by Inductively Coupled Plasma

    NASA Astrophysics Data System (ADS)

    Wei, Gang; Meng, Yuedong; Zhong, Shaofeng; Liu, Feng; Jiang, Zhongqing; Shu, Xingsheng; Ren, Zhaoxing; Wang, Xiangke

    2008-02-01

    An investigation was made into polystyrene (PS) grafted onto nanometre silicon carbide (SiC) particles. In our experiment, the grafting polymerization reaction was induced by a radio frequency (RF) inductively coupled plasma (ICP) treatment of the nanometre powder. FTIR (Fourier transform infrared spectrum) and XPS (X-ray photoelectron spectroscopy) results reveal that PS is grafted onto the surface of silicon carbide powder. An analysis is presented on the effectiveness of this approach as a function of plasma operating variables including the plasma treating power, treating time, and grafting reaction temperature and time.

  7. Coupling of Waveguide and Resonator by Inductive and Capacitive Irises for EPR Spectroscopy.

    PubMed

    Mett, R R; Sidabras, J W; Hyde, J S

    2009-01-01

    An analytic circuit model for slot coupling from a waveguide to a loop-gap resonator (LGR) in a context of electron paramagnetic resonance (EPR) spectroscopy is presented. The physical dimensions of the waveguide, iris, LGR, and aqueous sample are transformed into circuit values of inductance, capacitance, and resistance. These values are used in a solution of circuit equations that results in a prediction of the rf currents, magnitude and phase, frequency, and magnetic and electric stored energies near critical coupling. The circuit geometry reflects magnetic flux conservation between the iris and LGR as well as modification of the outer loop LGR currents by the iris. Unlike conventional models, coupling is not explicitly based on a mutual inductance between the iris and LGR. Instead, the conducting wall high frequency rf boundary condition is used to define surface currents, regions, and circuit topology with lumped-circuit values of self-inductance, capacitance, and resistance. Match is produced by a combination of self-inductive and capacitive circuit coupling. Two conditions must be met to achieve match. First, the equivalent resistance of the LGR as seen by the iris must be transformed into the waveguide characteristic impedance. This transformation is met at a particular frequency relative to the natural LGR resonance frequency. The frequency shift magnitude is largely determined by the LGR properties, weakly dependent on iris length and placement, and independent of other iris dimensions. The second condition for match is that the iris reactance at this frequency shift must cancel the residual reactance of the LGR. This second condition is sensitive to the iris dimensions. If both conditions are not simultaneously satisfied, overcoupling or undercoupling results. A slotted iris of equal length to the size of the large dimension of the waveguide is found to have many properties opposite to a conventional iris of shorter length. Notably, the magnetic field

  8. Determination of trace metals in marine biological reference materials by inductively coupled plasma mass spectrometry

    SciTech Connect

    Beauchemin, D.; McLaren, J.W.; Willie, S.N.; Berman, S.S.

    1988-04-01

    Inductively coupled plasma mass spectrometry (ICP-MS) was used for the analysis of two marine biological reference materials (dogfish liver tissue (DOLT-1) and dogfish muscle tissue (DORM-1)). The materials were put into solution by digestion in a nitric acid/hydrogen peroxide mixture. Thirteen elements (Na, Mg, Cr, Fe, Mn, Co, Ni, Cu, Zn, As, Cd, Hg, and Pb) were then determined. Accurate results were obtained by standard additions or isotope dilution techniques for all of these elements in DORM-1 and for all but Cr in DOLT-1.

  9. Time-resolved studies of particle effects in laser ablation inductively coupled plasma-mass spectrometry

    SciTech Connect

    Perdian, D.; Bajic, S.; Baldwin, D.; Houk, R.

    2007-11-13

    Time resolved signals in laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) are studied to determine the influence of experimental parameters on ICP-induced fractionation effects. Differences in sample composition and morphology, i.e., ablating brass, glass, or dust pellets, have a profound effect on the time resolved signal. Helium transport gas significantly decreases large positive signal spikes arising from large particles in the ICP. A binder for pellets also reduces the abundance and amplitude of spikes in the signal. MO{sup +} ions also yield signal spikes, but these MO{sup +} spikes generally occur at different times from their atomic ion counterparts.

  10. Temperature dependence of inductively coupled plasma assisted growth of TiN thin films.

    SciTech Connect

    Meng, W. J.; Curtis, T. J.; Rehn, L. E.; Baldo, P. M.; Materials Science Division; Louisiana State Univ.

    1999-11-01

    The use of low pressure high density plasmas to assist the synthesis of ceramic thin film materials is in its infancy. Using an inductively coupled plasma assisted magnetron sputtering system, we examine the dependence of plasma-assisted growth of TiN thin films on growth temperature at different ratios of ion flux to neutral atom flux. Our results indicate that a temperature independent densification of TiN films occurs above a certain ion to neutral atom flux ratio. As an example of this temperature independent densification, we demonstrate the formation of dense B1 TiN crystalline thin films at growth temperatures down to {approx}100 K.

  11. Production date determination of uranium-oxide materials by inductively coupled plasma mass spectrometry.

    PubMed

    Varga, Zsolt; Surányi, Gergely

    2007-09-01

    The paper describes analytical methods developed for the production date determination of uranium-based nuclear materials by the measurement of 230Th/234U isotope ratio. An improved sample preparation method for the destructive analysis involving extraction chromatographic separation with TEVA resin was applied prior to the measurement by isotope dilution inductively coupled plasma sector field mass spectrometry (ICP-SFMS). The results obtained were compared with the direct, quasi-non-destructive measurement using laser ablation ICP-SFMS technique for age determination. The advantages and limitations of both methods are discussed. PMID:17765059

  12. Characterization of silicon isotropic etch by inductively coupled plasma etcher for microneedle array fabrication

    NASA Astrophysics Data System (ADS)

    Ji, Jing; Tay, Francis E. H.; Miao, Jianmin; Sun, Jianbo

    2006-04-01

    This work investigates the isotropic etching properties in inductively coupled plasma (ICP) etcher for microneedle arrays fabrication. The effects of process variables including powers, gas and pressure on needle structure generation are characterized by factorial design of experiment (DOE). The experimental responses of vertical etching depth, lateral etching length, ratio of vertical etching depth to lateral etching length and photoresist etching rate are reported. The relevance of the etching variables is also presented. The obtained etching behaviours for microneedle structure generation will be applied to develop recipes to fabricate microneedles in designed dimensions.

  13. System Design for Ocean Sensor Data Transmission Based on Inductive Coupling

    NASA Astrophysics Data System (ADS)

    Xu, Ming; Liu, Fei; Zong, Yuan; Hong, Feng

    Ocean observation is the precondition to explore and utilize ocean. How to acquire ocean data in a precise, efficient and real-time way is the key question of ocean surveillance. Traditionally, there are three types of methods for ocean data transmission: underwater acoustic, GPRS via mobile network and satellite communication. However, none of them can meet the requirements of efficiency, accuracy, real-time and low cost at the same time. In this paper, we propose a new wireless transmission system for underwater sensors, which established on FGR wireless modules, combined with inductive coupling lab and offshore experiments confirmed the feasibility and effectiveness of the proposed wireless transmission system.

  14. Photon noise limited radiation detection with lens-antenna coupled microwave kinetic inductance detectors

    SciTech Connect

    Yates, S. J. C.; Baselmans, J. J. A.; Diener, P.; Endo, A.; Janssen, R. M. J.; Ferrari, L.; Baryshev, A. M.

    2011-08-15

    Microwave kinetic inductance detectors (MKIDs) have shown great potential for sub-mm instrumentation because of the high scalability of the technology. Here, we demonstrate for the first time in the sub-mm band (0.1-2 mm) a photon noise limited performance of a small antenna coupled MKID detector array and we describe the relation between photon noise and MKID intrinsic generation-recombination noise. Additionally, we use the observed photon noise to measure the optical efficiency of detectors to be 0.8 {+-} 0.2.

  15. Photon noise limited radiation detection with lens-antenna coupled microwave kinetic inductance detectors

    NASA Astrophysics Data System (ADS)

    Yates, S. J. C.; Baselmans, J. J. A.; Endo, A.; Janssen, R. M. J.; Ferrari, L.; Diener, P.; Baryshev, A. M.

    2011-08-01

    Microwave kinetic inductance detectors (MKIDs) have shown great potential for sub-mm instrumentation because of the high scalability of the technology. Here, we demonstrate for the first time in the sub-mm band (0.1-2 mm) a photon noise limited performance of a small antenna coupled MKID detector array and we describe the relation between photon noise and MKID intrinsic generation-recombination noise. Additionally, we use the observed photon noise to measure the optical efficiency of detectors to be 0.8 ± 0.2.

  16. Development of very small-diameter, inductively coupled magnetized plasma device.

    PubMed

    Kuwahara, D; Mishio, A; Nakagawa, T; Shinohara, S

    2013-10-01

    In order to miniaturize a high-density, inductively coupled magnetized plasma or helicon plasma to be applied to, e.g., an industrial application and an electric propulsion field, small helicon device has been developed. The specifications of this device along with the experimental results are described. We have succeeded in generating high-density (~10(19) m(-3)) plasmas using quartz tubes with very small diameters of 10 and 20 mm, with a radio frequency power ~1200 and 700 W, respectively, in the presence of the magnetic field less than 1 kG. PMID:24182105

  17. Cryptanalysis of Multiplicative Coupled Cryptosystems Based on the Chebyshev Polynomials

    NASA Astrophysics Data System (ADS)

    Shakiba, Ali; Hooshmandasl, Mohammad Reza; Meybodi, Mohsen Alambardar

    2016-06-01

    In this work, we propose a class of public-key cryptosystems called multiplicative coupled cryptosystem, or MCC for short, as well as discuss its security within three different models. Moreover, we discuss a chaotic instance of MCC based on the first and the second types of Chebyshev polynomials over real numbers for these three security models. To avoid round-off errors in floating point arithmetic as well as to enhance the security of the chaotic instance discussed, the Chebyshev polynomials of the first and the second types over a finite field are employed. We also consider the efficiency of the proposed MCCs. The discussions throughout the paper are supported by practical examples.

  18. Smart Sensor for Online Detection of Multiple-Combined Faults in VSD-Fed Induction Motors

    PubMed Central

    Garcia-Ramirez, Armando G.; Osornio-Rios, Roque A.; Granados-Lieberman, David; Garcia-Perez, Arturo; Romero-Troncoso, Rene J.

    2012-01-01

    Induction motors fed through variable speed drives (VSD) are widely used in different industrial processes. Nowadays, the industry demands the integration of smart sensors to improve the fault detection in order to reduce cost, maintenance and power consumption. Induction motors can develop one or more faults at the same time that can be produce severe damages. The combined fault identification in induction motors is a demanding task, but it has been rarely considered in spite of being a common situation, because it is difficult to identify two or more faults simultaneously. This work presents a smart sensor for online detection of simple and multiple-combined faults in induction motors fed through a VSD in a wide frequency range covering low frequencies from 3 Hz and high frequencies up to 60 Hz based on a primary sensor being a commercially available current clamp or a hall-effect sensor. The proposed smart sensor implements a methodology based on the fast Fourier transform (FFT), RMS calculation and artificial neural networks (ANN), which are processed online using digital hardware signal processing based on field programmable gate array (FPGA).

  19. Effect of bias application to plasma density in weakly magnetized inductively coupled plasma

    SciTech Connect

    Kim, Hyuk; Lee, Woohyun; Park, Wanjae; Whang, Ki-Woong

    2013-07-15

    Independent control of the ion flux and energy can be achieved in a dual frequency inductively coupled plasma (ICP) system. Typically, the plasma density is controlled by the high-frequency antenna radio-frequency (RF) power and the ion energy is controlled by the low-frequency bias RF power. Increasing the bias power has been known to cause a decrease in the plasma density in capacitively coupled discharge systems as well as in ICP systems. However, an applied axial magnetic field was found to sustain or increase the plasma density as bias power is increased. Measurements show higher electron temperatures but lower plasma densities are obtained in ordinary ICP systems than in magnetized ICP systems under the same neutral gas pressure and RF power levels. Explanations for the difference in the behavior of plasma density with increasing bias power are given in terms of the difference in the heating mechanism in ordinary unmagnetized and magnetized ICP systems.

  20. Simulation and Experimental Measurements of Inductively Coupled CF4 and CF4/Ar Plasmas

    NASA Technical Reports Server (NTRS)

    Hash, D. B.; Bose, D.; Rao, M. V. V. S.; Cruden, B. A.; Meyyappan, M.; Sharma, S. P.; Arnold, James O. (Technical Monitor)

    2000-01-01

    The recently developed code SEMS (semiconductor equipment modeling software)is applied to the simulation of CF4 and CF4/Ar inductively coupled plasmas (ICP). This work builds upon the earlier nitrogen, transformer coupled plasma (TCP) SEMS research by demonstrating its accuracy for more complex reactive mixtures, moving closer to the realization of a virtual plasma reactor. Attention is given to the etching of and/or formation of carbonaceous films on the quartz dielectric window and diagnostic aperatures. The simulations are validated through comparisons with experimental measurements using FTIR (Fourier Transform Infrared) and UV absorption spectroscopy for CFx and SiFx neutral radicals, QMS (quadrupole mass spectrometry) for the ions, and Langmuir probe measurements of electron number density and temperature in an ICP GEC reference cell.

  1. Langmuir Probe Measurements in an Inductively Coupled GEC Reference Cell Plasma

    NASA Technical Reports Server (NTRS)

    Ji, J. S.; Kim, J. S.; Cappelli, M. A.; Sharma, S. P.; Arnold, J. O. (Technical Monitor)

    1998-01-01

    Measurements of electron number density, electron temperature, and electron energy distribution function (EEDF) using a compensated Langmuir probe have been performed on an inductively (transformer ) coupled Gaseous Electronics Conference (GEC) reference cell plasma. The plasma source is operated with CH4, CF4, or their mixtures with argon. The effect of independently driving the electrode supporting the wafer on the probe data is studied. In particular, we find that the plasma structure depends on the phase in addition to the magnitude of the power coupled to the electrode relative to that of the transformer coil. The Langmuir probe is translated in a plane parallel to the electrode to investigate the spatial structure of the plasma. The probe data is also compared with fluid model predictions.

  2. Separation of actinides using capillary extraction chromatography-inductively coupled plasma mass spectrometry

    SciTech Connect

    Peterson, Dominic S

    2008-01-01

    Trace levels of actinides have been separated on extraction chromatography columns. Detection of the actinides was achieved using an inductively coupled plasma mass spectrometer (ICP-MS), which was coupled with the extraction chromatography system. In this study we compare 30 cm long, 4.6 mm ID columns to capillary columns (750 {micro}m ID) with lengths from 30 cm up to 150 cm. The columns that were tested were packed with TRU resin. We were able to separate a mixture of five actinides ({sup 232}Th, {sup 238}U, {sup 237}Np, {sup 239}pU, {sup 241}Am). This work has application to rapid bioassay as well as for automated separations of actinide materials.

  3. Active loaded plasmonic antennas at terahertz frequencies: Optical control of their capacitive-inductive coupling

    NASA Astrophysics Data System (ADS)

    Georgiou, G.; Tserkezis, C.; Schaafsma, M. C.; Aizpurua, J.; Gómez Rivas, J.

    2015-03-01

    We demonstrate the photogeneration of loaded dipole plasmonic antennas resonating at THz frequencies. This is achieved by the patterned optical illumination of a semiconductor surface using a spatial light modulator. Our experimental results indicate the existence of capacitive and inductive coupling of localized surface plasmon polaritons. By varying the load in the antenna gap we are able to switch between both coupling regimes. Furthermore, we determine experimentally the effective impedance of the antenna load and verify that this load can be effectively expressed as a LC resonance formed by a THz inductor and capacitor connected in a parallel circuit configuration. These findings are theoretically supported by full electrodynamic calculations and by simple concepts of lumped circuit theory. Our results open new possibilities for the design of active THz circuits for optoelectronic devices.

  4. Ion flux and ion distribution function measurements in synchronously pulsed inductively coupled plasmas

    SciTech Connect

    Brihoum, Melisa; Cunge, Gilles; Darnon, Maxime; Joubert, Olivier; Gahan, David; Braithwaite, Nicholas St. J.

    2013-03-15

    Changes in the ion flux and the time-averaged ion distribution functions are reported for pulsed, inductively coupled RF plasmas (ICPs) operated over a range of duty cycles. For helium and argon plasmas, the ion flux increases rapidly after the start of the RF pulse and after about 50 {mu}s reaches the same steady state value as that in continuous ICPs. Therefore, when the plasma is pulsed at 1 kHz, the ion flux during the pulse has a value that is almost independent of the duty cycle. By contrast, in molecular electronegative chlorine/chlorosilane plasmas, the ion flux during the pulse reaches a steady state value that depends strongly on the duty cycle. This is because both the plasma chemistry and the electronegativity depend on the duty cycle. As a result, the ion flux is 15 times smaller in a pulsed 10% duty cycle plasma than in the continuous wave (CW) plasma. The consequence is that for a given synchronous RF biasing of a wafer-chuck, the ion energy is much higher in the pulsed plasma than it is in the CW plasma of chlorine/chlorosilane. Under these conditions, the wafer is bombarded by a low flux of very energetic ions, very much as it would in a low density, capacitively coupled plasma. Therefore, one can extend the operating range of ICPs through synchronous pulsing of the inductive excitation and capacitive chuck-bias, offering new means by which to control plasma etching.

  5. Simulation of Plasma Characteristics for Inductively Coupled Argon Plasma Using Dual-Frequency Antennas

    NASA Astrophysics Data System (ADS)

    Li, Xue-Chun; Sun, Xiao-Yan; Wang, You-Nian

    2014-10-01

    A large-area wafer size is necessary for plasma processing in the micro-electronics industry. However, it is one of the most important issues to obtain uniform plasma over a large-area substrate in addition to high-density plasmas for the plasma processing. Recently, the experimental study on the dual-frequency inductively coupled plasma (ICP) has been reported as a mean of improving the plasma uniformity over the large-area substrate. In this work, we develop a self-consistent method combined with the electromagnetic theory and fluid model to simulate the plasma characteristics for dual-frequency inductively coupled argon plasma. In the model, the ICP source consists of two planar-spiral coils. We investigate the plasma uniformity problem by adjusting the parameters of the two coils, such as the RF current, the position of the coils and the RF frequency ratio. It was found that the uniformity of the ion density over the wafer is improved with dual-frequency antennas comparing with a single-frequency antenna. The plasma uniformity increases when the coils are located farther from the centre of the ICP source. It is consistent with the experimental study. This work was supported by the National Natural Science Foundation of China (No. 11175034, No. 11075029).

  6. Lithium Iron Phosphate Powders and Coatings Obtained by Means of Inductively Coupled Thermal Plasma

    NASA Astrophysics Data System (ADS)

    Major, K.; Veilleux, J.; Brisard, G.

    2016-01-01

    Lithium-ion batteries have high energy efficiency and good cycling life and are considered as one of the best energy storage device for hybrid and/or electrical vehicle. Still, several problems must be solved prior to a broad adoption by the automotive industry: energy density, safety, and costs. To enhance both energy density and safety, the current study aims at depositing binder-free cathode materials using inductively coupled thermal plasma. In a first step, lithium iron phosphate (LiFePO4) powders are synthesized in an inductively coupled thermal plasma reactor and dispersed in a conventional polyvinylidene fluoride (PVDF) binder. Then, binder-free LiFePO4 coatings are directly deposited onto nickel current collectors by solution precursor plasma spraying (SPPS). The morphology, microstructure, and composition of the synthesized LiFePO4 powders and coatings are fully characterized by electronic microscopy, x-ray diffraction, and x-ray photoelectron spectroscopy (XPS). Quantifying Li with XPS requires the substitution of iron with manganese in the SPPS precursors (LiMPO4, where M = Fe or Mn). The plasma-derived cathodes (with and without PVDF binder) are assembled in button cells and tested. Under optimized plasma conditions, cyclic voltammetry shows that the electrochemical reversibility of plasma-derived cathodes is improved over that of conventional sol-gel-derived LiFePO4 cathodes.

  7. Inductively coupled plasma etching of BZN thin films in SF6/Ar plasmas

    NASA Astrophysics Data System (ADS)

    Wang, Gang; Li, Ping; Zhang, Guojun; Li, Wei; Dai, Liping; Jiang, Jing

    2013-03-01

    Etching mechanisms and characteristics of bismuth zinc niobate (BZN) thin films were investigated in inductively coupled SF6/Ar plasmas. The influences of various etching parameters including the gas flow ratio, process pressure, and ICP power on the etching results were analyzed. It is found that the chemical etching with F radicals was more effective than the physical sputtering etching with Ar ions for the inductively coupled plasma etching of BZN thin films. The mechanism of ion assisted chemical etching of BZN thin films in SF6/Ar plasmas was proposed. A maximum etch rate of approximately 43.15 nm/min for the BZN thin film was obtained at the optimum etching conditions: 3/2 for the SF6/Ar gas flow ratio, 10 mTorr for the process pressure, and 600 W for the ICP power. The surface morphology of the etched BZN thin film was observed, where was smooth and clean and no post-etch residues were remained.

  8. Determination of the rare-earth elements in geological materials by inductively coupled plasma mass spectrometry

    USGS Publications Warehouse

    Lichte, F.E.; Meier, A.L.; Crock, J.G.

    1987-01-01

    A method of analysis of geological materials for the determination of the rare-earth elements using the Inductively coupled plasma mass spectrometric technique (ICP-MS) has been developed. Instrumental parameters and factors affecting analytical results have been first studied and then optimized. Samples are analyzed directly following an acid digestion, without the need for separation or preconcentration with limits of detection of 2-11 ng/g, precision of ?? 2.5% relative standard deviation, and accuracy comparable to inductively coupled plasma emission spectrometry and instrumental neutron activation analysis. A commercially available ICP-MS instrument is used with modifications to the sample introduction system, torch, and sampler orifice to reduce the effects of high salt content of sample solutions prepared from geologic materials. Corrections for isobaric interferences from oxide ions and other diatomic and triatomic ions are made mathematically. Special internal standard procedures are used to compensate for drift in metahmetal oxide ratios and sensitivity. Reference standard values are used to verify the accuracy and utility of the method.

  9. Inductively coupled microfluidic pressure meter for in vivo monitoring of cerebrospinal fluid shunt function.

    PubMed

    Song, S-H; Gillies, G T; Begley, M R; Utz, M; Broaddus, W C

    2012-04-01

    A microfluidic pressure sensor with inductively coupled, wireless readout capability has been developed for integration into cerebrospinal fluid shunt valve implants. The sensor consists of a deformable PDMS film that is bonded over a microfluidic reservoir, forming a fluidic capacitor. Deflection of the capacitor membrane is detected remotely through a shift in the resonance frequency of a micro-fabricated LC circuit. Sensors were fabricated by a combination of conventional MEMS technologies and rapid soft lithography. A direct pattern transfer technique was used to pattern the deformable PDMS film with a metal coating for the capacitive readout. The mechanical response of the fluidic capacitor was characterized by measuring the deflection of the PDMS film using an extrinsic Fabry-Perot interferometer (EFPI), and wireless sensing was demonstrated by the shift in resonance frequency of the sensor via an inductively coupled antenna. The sensor transduces pressure into a change in resonant frequency with sensitivity > 3.4 ppm Pa⁻¹ and responsivity 4.6 kHz Pa⁻¹, over a dynamic range of 0~3 kPa. PMID:22316101

  10. Prospective Real Time Head Motion Correction Using Inductively Coupled Wireless NMR Probes

    PubMed Central

    Sengupta, Saikat; Tadanki, Sasidhar; Gore, John C.; Welch, E. Brian

    2014-01-01

    Purpose Head motion continues to be a major source of artifacts and data quality degradation in MRI. The goal of this work was to develop and demonstrate a novel technique for prospective, 6 degrees of freedom (6DOF) rigid body motion estimation and real time motion correction using inductively coupled wireless nuclear magnetic resonance (NMR) probe markers. Methods Three wireless probes that are inductively coupled with the scanner’s RF setup serve as fiducials on the subject’s head. A 12 ms linear navigator module is interleaved with the imaging sequence for head position estimation, and scan geometry is updated in real time for motion compensation. Flip angle amplification in the markers allows the use of extremely small navigator flip angles (~1°). A novel algorithm is presented to identify marker positions in the absence of marker specific receive channels. The method is demonstrated for motion correction in 1 mm3 gradient recalled echo experiments in phantoms and humans. Results Significant improvement of image quality is demonstrated in phantoms and human volunteers under different motion conditions. Conclusion A novel real time 6 DOF head motion correction technique based on wireless NMR probes is demonstrated in high resolution imaging at 7 Tesla. PMID:24243810

  11. Surface modification of polypropylene separators in lithium-ion batteries using inductively coupled plasma treatment.

    PubMed

    Son, Jinyoung; Kim, Min-Sik; Lee, Hyun Woo; Yu, Jong-Sung; Kwon, Kwang-Ho

    2014-12-01

    We describe herein an improvement in the surface wettability of plasma-treated separators for use in lithium-ion batteries. We treated the separators with an O2/Ar inductively coupled plasma to increase their surface energy. The plasma treatment on the separator and plasma diagnostic experiments were performed in an inductively coupled plasma (ICP) reactor. The fraction of Ar in the O2/Ar plasma was changed from 0% to 100%. The plasma diagnostics were performed using optical emission spectroscopy and a double Langmuir probe. To confirm the morphological change of the separator membrane by the plasma treatment, we used the scanning electron microscopy. The surface energy measurements were performed using the drop method. We found that the plasma treatment transformed the separator from a hydrophobic membrane to a hydrophilic one, thereby achieving high separator wettability. After the treatment of the separators with O2/Ar plasma, the batteries exhibited better cycle performance and rate capacity than those employing the untreated ones. PMID:25971067

  12. Resonant RF network antennas for large-area and large-volume inductively coupled plasma sources

    NASA Astrophysics Data System (ADS)

    Hollenstein, Ch; Guittienne, Ph; Howling, A. A.

    2013-10-01

    Large-area and large-volume radio frequency (RF) plasmas are produced by different arrangements of an elementary electrical mesh consisting of two conductors interconnected by a capacitor at each end. The obtained cylindrical and planar RF networks are resonant and generate very high RF currents. The input impedance of such RF networks shows the behaviour of an RLC parallel resonance equivalent circuit. The real impedance at the resonance frequency is of great advantage for power matching compared with conventional inductive devices. Changes in the RLC equivalent circuit during the observed E-H transition will allow future interpretation of the plasma-antenna coupling. Furthermore, high power transfer efficiencies are found during inductively coupled plasma (ICP) operation. For the planar RF antenna network it is shown that the E-H transition occurs simultaneously over the entire antenna. The underlying physics of these discharges induced by the resonant RF network antenna is found to be identical to that of the conventional ICP devices described in the literature. The resonant RF network antenna is a new versatile plasma source, which can be adapted to applications in industry and research.

  13. Neutral depletion in inductively coupled plasmas using hybrid-type direct simulation Monte Carlo

    SciTech Connect

    Shimada, Masashi; Tynan, George R.; Cattolica, Robert

    2008-02-01

    Neutral and ion transport phenomena were simulated by a hybrid-type direct simulation Monte Carlo (DSMC) method for a one-dimensional (1D) electrostatic plasma in Ar/N{sub 2} mixtures to identify the mechanism of neutral depletion. The results show that gas heating and pressure balance are the main mechanisms of neutral depletion in an inductively coupled plasma. When plasma pressure becomes comparable to neutral pressure in high density plasma sources (T{sub e}{approx}2-5 eV, n{sub e}{approx}10{sup 11}-10{sup 12} cm{sup -3}), the total pressure (neutral pressure and plasma pressure) is conserved. Therefore, the finite plasma pressure (mainly electron pressure) reduces the neutral pressure. Neutrals collide with ions that have been accelerated by the ambipolar electric field and with Franck-Condon dissociated atoms, resulting in gas heating. Significant neutral depletion (up to 90%) is found at the typical condition of inductively coupled plasma process reactors. The resulting neutral depletion enhances the plasma transport to the surrounding wall, increases the particle loss, and decreases the plasma density.

  14. Viscous effects on motion and heating of electrons in inductively coupled plasma reactors

    SciTech Connect

    Chang, C.H.; Bose, D.

    1999-10-01

    A transport model is developed for nonlocal effects on motion and heating of electrons in inductively coupled plasma reactors. The model is based on the electron momentum equation derived from the Boltzmann equation, retaining anisotropic stress components which in fact are viscous stresses. The resulting model consists of transport equations for the magnitude of electron velocity oscillation and terms representing energy dissipation due to viscous stresses in the electron energy equation. In this model, electrical current is obtained in a nonlocal manner due to viscous effects, instead of Ohm's law or the electron momentum equation without viscous effects, while nonlocal heating of electrons is represented by the viscous dissipation. Computational results obtained by two-dimensional numerical simulations show that nonlocal determination of electrical current indeed is important, and viscous dissipation becomes an important electron heating mechanism at low pressures. It is suspected that viscous dissipation in inductively coupled plasma reactors in fact represents stochastic heating of electrons, and this possibility is exploited by discussing physical similarities between stochastic heating and energy dissipation due to the stress tensor.

  15. Residual capacitive coupling and the measurement of permittivity in magnetic induction tomography.

    PubMed

    Griffiths, H; Gough, W; Watson, S; Williams, R J

    2007-07-01

    In an ideal magnetic induction tomography (MIT) system, the coupling between the coils and the sample is entirely by the magnetic field. In a practical system, unwanted electric-field (capacitive) coupling can also exist and cause large errors in the MIT measurements unless the hardware is designed carefully. A series of tests was carried out to assess the magnitude of capacitive coupling present in a 10 MHz MIT system designed for biomedical use and other applications involving low-conductivity samples (coupling was very small compared with the true MIT signal. Because the contamination was small, it was demonstrated possible to derive the permittivity of the sample from the real part of the MIT signal. This was shown to work well when the conductivity of the sample was less than about 0.5 S m(-1), but for higher conductivities, when the skin depth became comparable with the width of the sample, the commonly used theoretical expression for the MIT signal began to break down. This implies that the measurement of permittivity (and permeability) in real biological tissues (which have conductivities of up to 2 S m(-1)) will require a more detailed derivation taking into account both the real and imaginary parts of the signals. PMID:17664645

  16. Electrical characterization of an inductively coupled gaseous electronics conference reference cell

    SciTech Connect

    Singh, S. V.; Pargmann, C.

    2008-10-15

    Plasma parameters and particularly the external electrical operational parameters are examined with respect to mode transition and hysteresis. The external electrical parameters such as antenna current (I{sub c}) and antenna voltage (V{sub c}) amplitudes are measured after the matching network and discussed for an inductively coupled argon discharge. A wide range of discharge conditions by varying applied power (up to 150 W at 13.56 MHz), gas pressure (0.7-7.5 Pa), and electrostatic coupling strength are measured for a gaseous electronics conference radio frequency reference cell. The effect on the power coupling efficiency by varying electrostatic coupling strength is studied via implementing two distinct grounded Faraday shields, in addition to the original nonshielded condition. A brief discussion on the evolution of floating potential, plasma potential, electron density, and electron energy distribution function with power and pressure is also presented mainly in context to mode transitions and hysteresis. Relatively smooth transitions in the plasma parameters and in the external electrical parameters are measured close to H to E mode transition region. Contrary to plasma parameters, however, the reverse transition from E to H mode was found to be abrupt in external parameters. The plasma parameters are measured using a commercial Langmuir probe, whereas the antenna currents and voltages are measured using a homebuilt Rogowski coil and capacitor divider, respectively.

  17. Simulation of low-pressure inductively coupled plasmas: Non-local effects and pulsed power operation

    NASA Astrophysics Data System (ADS)

    Ramamurthi, Badri

    For modeling of low-pressure Inductively Coupled Plasma (ICP) discharges, a number of approaches have been proposed with varying degree of complexity. A self-consistent 1-D model was developed in this work to study the effects of non-local electron conductivity on power absorption and plasma density profiles in a planar inductively coupled argon discharge at low pressures (< 10 mTorr). The self-consistent kinetic description of the discharge included three modules: (1) an EEDF module to compute a non-Maxwellian EEDF, (2) a non-local electron conductivity module which predicted current distribution in the plasma as an integral over the electric field and solved Maxwell's equations to find the self-consistent electric field as well as the non-local power deposition profile and (3) a Heavy Species Transport (HST) module which solved for the ion and metastable atom density and velocity. Results from the full model were then compared with those obtained by using a local conductivity model (Ohm's law) for the RF current. For 10 mTorr, the EEDF was found to be almost Maxwellian with electron temperature ˜ 3 V. As a result, the plasma density profiles obtained from the local and non-local cases were almost identical for the same total power. Interestingly, a similar result was obtained even for a pressure of 1 mTorr where the EEDF was non-Maxwellian. This suggests that as far as species density and flux are concerned, local conductivity models, with lesser computational expense, can be employed even in the non-local regime. Comparisons between simulation and experiment for RF field and current density showed better agreement for non-local model compared with local model. A two-dimensional (r,z) continuum model was then developed to study the spatio-temporal dynamics of a pulsed power (square-wave modulated) discharge in argon (electropositive) and chlorine (electronegative) sustained in an inductively coupled plasma (ICP) reactor with a planar coil. The self

  18. Biomonitoring of hair samples by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS)

    NASA Astrophysics Data System (ADS)

    Sela, H.; Karpas, Z.; Zoriy, M.; Pickhardt, C.; Becker, J. S.

    2007-03-01

    An analytical method for determining essential elements (Zn, Fe and Cu) and toxic elements (Cr, Pb and U) on single hair strands by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-SFMS) using a double focusing sector field mass spectrometer was developed. Results obtained directly using LA-ICP-SFMS of hair were compared with those measured by inductively coupled plasma quadrupole mass spectrometry (ICP-QMS) of solutions of digested hair samples and the analytical methods were found to agree well. Different quantification strategies for trace element determination in hair samples such as external calibration, standard addition and isotope dilution were compared and demonstrated for uranium. For uranium determination in powdered hair by LA-ICP-MS solution-based calibration was applied by coupling the laser ablation chamber to an ultrasonic nebulizer. The significance of single hair analysis by LA-ICP-SFMS was demonstrated by a case study of a person who changed living environment. Differences in the uranium content observed along the single hair strand correlated with the changes in the level of uranium in drinking water. The uranium concentration in a single hair decreased from 212 to 18 ng g-1 with a change in the uranium concentration in drinking water from 2000 to 30 ng l-1. In addition, measurements of uranium isotope ratios showed a natural isotopic composition throughout the whole period in the drinking water, as well as in the hair samples. This paper demonstrates the potential use of laser ablation ICP-MS to provide measurements on a single hair strand and its potential to become a very powerful tool in hair analysis for biological monitoring.

  19. Permethrin Induction of Multiple Cytochrome P450 Genes in Insecticide Resistant Mosquitoes, Culex quinquefasciatus

    PubMed Central

    Gong, Youhui; Li, Ting; Zhang, Lee; Gao, Xiwu; Liu, Nannan

    2013-01-01

    The expression of some insect P450 genes can be induced by both exogenous and endogenous compounds and there is evidence to suggest that multiple constitutively overexpressed P450 genes are co-responsible for the development of resistance to permethrin in resistant mosquitoes. This study characterized the permethrin induction profiles of P450 genes known to be constitutively overexpressed in resistant mosquitoes, Culex quinquefasciatus. The gene expression in 7 of the 19 P450 genes CYP325K3v1, CYP4D42v2, CYP9J45, (CYP) CPIJ000926, CYP325G4, CYP4C38, CYP4H40 in the HAmCqG8 strain, increased more than 2-fold after exposure to permethrin at an LC50 concentration (10 ppm) compared to their acetone treated counterpart; no significant differences in the expression of these P450 genes in susceptible S-Lab mosquitoes were observed after permethrin treatment. Eleven of the fourteen P450 genes overexpressed in the MAmCqG6 strain, CYP9M10, CYP6Z12, CYP9J33, CYP9J43, CYP9J34, CYP306A1, CYP6Z15, CYP9J45, CYPPAL1, CYP4C52v1, CYP9J39, were also induced more than doubled after exposure to an LC50 (0.7 ppm) dose of permethrin. No significant induction in P450 gene expression was observed in the susceptible S-Lab mosquitoes after permethrin treatment except for CYP6Z15 and CYP9J39, suggesting that permethrin induction of these two P450 genes are common to both susceptible and resistant mosquitoes while the induction of the others are specific to insecticide resistant mosquitoes. These results demonstrate that multiple P450 genes are co-up-regulated in insecticide resistant mosquitoes through both constitutive overexpression and induction mechanisms, providing additional support for their involvement in the detoxification of insecticides and the development of insecticide resistance. PMID:24155662

  20. Coupling an induction motor type generator to ac power lines. [making windmill generators compatible with public power lines

    NASA Technical Reports Server (NTRS)

    Nola, F. J. (Inventor)

    1984-01-01

    A system for coupling an induction motor type generator to an A.C. power line includes an electronic switch means that is controlled by a control system and is regulated to turn on at a relatively late point in each half cycle of its operation. The energizing power supplied by the line to the induction motor type generator is decreased and the net power delivered to the line is increased.

  1. Mechanism for Plasma Etching of Shallow Trench Isolation Features in an Inductively Coupled Plasma

    NASA Astrophysics Data System (ADS)

    Agarwal, Ankur; Rauf, Shahid; He, Jim; Choi, Jinhan; Collins, Ken

    2011-10-01

    Plasma etching for microelectronics fabrication is facing extreme challenges as processes are developed for advanced technological nodes. As device sizes shrink, control of shallow trench isolation (STI) features become more important in both logic and memory devices. Halogen-based inductively coupled plasmas in a pressure range of 20-60 mTorr are typically used to etch STI features. The need for improved performance and shorter development cycles are placing greater emphasis on understanding the underlying mechanisms to meet process specifications. In this work, a surface mechanism for STI etch process will be discussed that couples a fundamental plasma model to experimental etch process measurements. This model utilizes ion/neutral fluxes and energy distributions calculated using the Hybrid Plasma Equipment Model. Experiments are for blanket Si wafers in a Cl2/HBr/O2/N2 plasma over a range of pressures, bias powers, and flow rates of feedstock gases. We found that kinetic treatment of electron transport was critical to achieve good agreement with experiments. The calibrated plasma model is then coupled to a string-based feature scale model to quantify the effect of varying process parameters on the etch profile. We found that the operating parameters strongly influence critical dimensions but have only a subtle impact on the etch depths.

  2. Characterization of Inductively Coupled Plasmas in High Power, High Pressure Regime

    NASA Astrophysics Data System (ADS)

    Wang, Jun-Chieh; Kenney, Jason; Agarwal, Ankur; Nichols, Michael; Rogers, James; Rauf, Shahid

    2015-09-01

    Inductively coupled plasmas (ICP) are widely used in the microelectronic industry for thin film etching. ICPs have typically been operated at low gas pressures (<50 mTorr) and they have been well-characterized in this regime. Several applications requiring high etch rates (e.g., vertical NAND etch) have recently extended the use of ICPs to the high power (>4000 W) and high pressure (>100 mTorr) regime. ICP operation in this high-power, high-pressure regime imposes a tremendous challenge of achieving good plasma uniformity over large substrates. This necessitates a good theoretical understanding of the underlying physics, thorough experimental characterization, and more accurate numerical models for hardware design guidance. In this study, we will focus on the characterization of ICP in the high-power, high-pressure regime. Computational modeling is done using CRTRS, our in-house 2D/3D plasma model. The fluid plasma model is coupled to a circuit model to self-consistently account for the capacitive coupling from the coils that is expected to dominate in this operating regime. Properties of Ar plasma will be discussed and compared with experiments. The impact of critical operating parameters such as ICP power, pressure, flow rate, and current ratio (in multi-coil antenna structures) on plasma characteristics will be examined. Results in relevant processing gases will also be discussed.

  3. Bottom-series coupled quadrature VCO using the inductive gate voltage boosting technique

    NASA Astrophysics Data System (ADS)

    Jang, Sheng-Lyang; Chou, Li-Te

    2013-09-01

    This article presents a new low-voltage bottom-series coupled quadrature voltage-controlled oscillator (QVCO), which consists of two n-core cross-coupled VCOs with the bottom-series coupling transistors. The low-voltage operation is obtained via an inductive gate voltage boosting technique. The proposed CMOS QVCO has been implemented with the TSMC 0.18 µm CMOS technology and the die area is 0.897 × 0.767 mm2. At the supply voltage of 0.7 V, the total power consumption is 1.5 mW. The free-running frequency of the QVCO is tuneable from 3.77 to 4.12 GHz as the tuning voltage is varied from 0.0 to 0.7 V. The measured phase noise at 1 MHz frequency offset is -123.35 dBc/Hz at the oscillation frequency of 4.12 GHz and the figure of merit of the proposed QVCO is -193.5 dBc/Hz.

  4. Reduced electron temperature in a magnetized inductively-coupled plasma with internal coil

    SciTech Connect

    Arancibia Monreal, J.; Chabert, P.; Godyak, V.

    2013-10-15

    The effect of magnetic filtering on the electron energy distribution function is studied in an inductive discharge with internal coil coupling. The coil is placed inside the plasma and driven by a low-frequency power supply (5.8 MHz) which leads to a very high power transfer efficiency. A permanent dipole magnet may be placed inside the internal coil to produce a static magnetic field around 100 Gauss. The coil and the matching system are designed to minimize the capacitive coupling to the plasma. Capacitive coupling is quantified by measuring the radiofrequency (rf) plasma potential with a capacitive probe. Without the permanent magnet, the rf plasma potential is significantly smaller than the electron temperature. When the magnet is present, the rf plasma potential increases. The electron energy distribution function is measured as a function of space with and without the permanent magnet. When the magnet is present, electrons are cooled down to low temperature in the downstream region. This region of low electron temperature may be useful for plasma processing applications, as well as for efficient negative ion production.

  5. Energetic electron avalanches and mode transitions in planar inductively coupled radio-frequency driven plasmas operated in oxygen

    SciTech Connect

    Zaka-ul-Islam, M.; Niemi, K.; Gans, T.; O'Connell, D.

    2011-07-25

    Space and phase resolved optical emission spectroscopic measurements reveal that in certain parameter regimes, inductively coupled radio-frequency driven plasmas exhibit three distinct operation modes. At low powers, the plasma operates as an alpha-mode capacitively coupled plasma driven through the dynamics of the plasma boundary sheath potential in front of the antenna. At high powers, the plasma operates in inductive mode sustained through induced electric fields due to the time varying currents and associated magnetic fields from the antenna. At intermediate powers, close to the often observed capacitive to inductive (E-H) transition regime, energetic electron avalanches are identified to play a significant role in plasma sustainment, similar to gamma-mode capacitively coupled plasmas. These energetic electrons traverse the whole plasma gap, potentially influencing plasma surface interactions as exploited in technological applications.

  6. Analytical Model and Optimized Design of Power Transmitting Coil for Inductively Coupled Endoscope Robot.

    PubMed

    Ke, Quan; Luo, Weijie; Yan, Guozheng; Yang, Kai

    2016-04-01

    A wireless power transfer system based on the weakly inductive coupling makes it possible to provide the endoscope microrobot (EMR) with infinite power. To facilitate the patients' inspection with the EMR system, the diameter of the transmitting coil is enlarged to 69 cm. Due to the large transmitting range, a high quality factor of the Litz-wire transmitting coil is a necessity to ensure the intensity of magnetic field generated efficiently. Thus, this paper builds an analytical model of the transmitting coil, and then, optimizes the parameters of the coil by enlarging the quality factor. The lumped model of the transmitting coil includes three parameters: ac resistance, self-inductance, and stray capacitance. Based on the exact two-dimension solution, the accurate analytical expression of ac resistance is derived. Several transmitting coils of different specifications are utilized to verify this analytical expression, being in good agreements with the measured results except the coils with a large number of strands. Then, the quality factor of transmitting coils can be well predicted with the available analytical expressions of self- inductance and stray capacitance. Owing to the exact estimation of quality factor, the appropriate coil turns of the transmitting coil is set to 18-40 within the restrictions of transmitting circuit and human tissue issues. To supply enough energy for the next generation of the EMR equipped with a Ø9.5×10.1 mm receiving coil, the coil turns of the transmitting coil is optimally set to 28, which can transfer a maximum power of 750 mW with the remarkable delivering efficiency of 3.55%. PMID:26292335

  7. Spectroscopic measurements in low temperature inductively coupled RF discharges in hydrogen

    NASA Astrophysics Data System (ADS)

    Huebschman, Michael Lee

    1999-10-01

    Noninvasive spectroscopic measurements of density and temperature which are characteristic of plasma processing tools have been obtained on inductively driven low- density hydrogen plasma sources. These measurements allow full radial and axial profiles of electron density and temperature to be estimated from absolutely calibrated multichannel spectroscopic measurements of upper state densities and a collisional radiative model that accounts for both collisional and radiative processes. The electron temperature and density were estimated by minimizing the least square deviation of measured population of upper state densities and the prediction of the collisional radiative model. Profiles were obtained over a range of powers from 50 to 200 Watts and pressures from 5 to 50 mTorr in hydrogen in a small cylindrical source. Typical density and temperature measurement profiles have been plotted to characterize the apparatus. An elementary sensitivity analysis, which includes plasma opacity and non- Maxwellian electron distributions, showed that, for hydrogen at processing pressures, the accuracy of the technique is relatively unaffected by these perturbations. The molecular dissociation processes were found to be important in determining the steady state densities of atomic hydrogen but had little affect in populating the upper state hydrogen levels for the plasma conditions measured. A hydrogen working gas and simple geometry were chosen to simplify detailed comparisons with a 2D computational model (INDUCT95) which uses a fluid approximation for the plasma and neutral gas. The code calculates the inductive coupling of the 13.5MHz RIF source and collisional, radiative, and wall losses as well as a complete chemistry model for H2, H, H+, H 3+. Good qualitative agreement between the initial model calculations and experimental data have been obtained over part of the operational range. Lastly, to characterize the apparatus for use in wafer cleaning, radial profiles of the

  8. Quantitative Characterization of Gold Nanoparticles by Coupling Thin Layer Chromatography with Laser Ablation Inductively Coupled Plasma Mass Spectrometry.

    PubMed

    Yan, Neng; Zhu, Zhenli; Jin, Lanlan; Guo, Wei; Gan, Yiqun; Hu, Shenghong

    2015-06-16

    Metal nanoparticles (NPs) determination has recently attracted considerable attention because of the continuing boom of nanotechnology. In this study, a novel method for separation and quantitative characterization of NPs in aqueous suspension was established by coupling thin layer chromatography (TLC) with laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). Gold nanoparticles (AuNPs) of various sizes were used as the model system. It was demonstrated that TLC not only allowed separation of gold nanoparticles from ionic gold species by using acetyl acetone/butyl alcohol/triethylamine (6:3:1, v/v) as the mobile phase, but it also achieved the separation of differently sized gold nanoparticles (13, 34, and 47 nm) by using phosphate buffer (0.2 M, pH = 6.8), Triton X-114 (0.4%, w/v), and EDTA (10 mM) as the mobile phase. Various experimental parameters that affecting TLC separation of AuNPs, such as the pH of the phosphate buffer, the coating of AuNPs, the concentrations of EDTA and Triton X-114, were investigated and optimized. It was found that separations of AuNPs by TLC displayed size dependent retention behavior with good reproducibility, and the retardation factors (R(f) value) increased linearly with decreasing nanoparticle size. The analytical performance of the present method was evaluated under optimized conditions. The limits of detection were in the tens of pg range, and repeatability (RSD, n = 7) was 6.3%, 5.9%, and 8.3% for 30 ng of 13 nm AuNPs, 34 nm AuNPs, and 47 nm AuNPs, respectively. The developed TLC-LA-ICP-MS method has also been applied to the analysis of spiked AuNPs in lake water, river water, and tap water samples. PMID:26005902

  9. Revisiting the electrochemical impedance spectroscopy of magnesium with online inductively coupled plasma atomic emission spectroscopy.

    PubMed

    Shkirskiy, Viacheslav; King, Andrew D; Gharbi, Oumaïma; Volovitch, Polina; Scully, John R; Ogle, Kevin; Birbilis, Nick

    2015-02-23

    The electrochemical impedance of reactive metals such as magnesium is often complicated by an obvious inductive loop with decreasing frequency of the AC polarising signal. The characterisation and ensuing explanation of this phenomenon has been lacking in the literature to date, being either ignored or speculated. Herein, we couple electrochemical impedance spectroscopy (EIS) with online atomic emission spectroelectrochemistry (AESEC) to simultaneously measure Mg-ion concentration and electrochemical impedance spectra during Mg corrosion, in real time. It is revealed that Mg dissolution occurs via Mg(2+) , and that corrosion is activated, as measured by AC frequencies less than approximately 1 Hz approaching DC conditions. The result of this is a higher rate of Mg(2+) dissolution, as the voltage excitation becomes slow enough to enable all Mg(2+) -enabling processes to adjust in real time. The manifestation of this in EIS data is an inductive loop. The rationalisation of such EIS behaviour, as it relates to Mg, is revealed for the first time by using concurrent AESEC. PMID:25425247

  10. Ion energy and angular distributions in inductively coupled Argon RF discharges

    SciTech Connect

    Woodworth, J.R.; Riley, M.E.; Meister, D.C.

    1996-03-01

    We report measurements of the energies and angular distributions of positive ions in an inductively coupled argon plasma in a GEC reference cell. Use of two separate ion detectors allowed measurement of ion energies and fluxes as a function of position as well as ion angular distributions on the discharge centerline. The inductive drive on our system produced high plasma densities (up to 10{sup 12}/cm{sup 3} electron densities) and relatively stable plasma potentials. As a result, ion energy distributions typically consisted of a single feature well separated from zero energy. Mean ion energy was independent of rf power and varied inversely with pressure, decreasing from 29 eV to 12 eV as pressure increased form 2.4 m Torr to 50 mTorr. Half-widths of the ion angular distributions in these experiments varied from 5 degrees to 12.5 degrees, or equivalently, transverse temperatures varied form 0.2 to 0.5 eV with the distributions broadening as either pressure or RF power were increased.

  11. Characterization of stationary and pulsed inductively coupled RF discharges for plasma sterilization

    NASA Astrophysics Data System (ADS)

    Gans, T.; Osiac, M.; O'Connell, D.; Kadetov, V. A.; Czarnetzki, U.; Schwarz-Selinger, T.; Halfmann, H.; Awakowicz, P.

    2005-05-01

    Sterilization of bio-medical materials using radio frequency (RF) excited inductively coupled plasmas (ICPs) has been investigated. A double ICP has been developed and studied for homogenous treatment of three-dimensional objects. Sterilization is achieved through a combination of ultraviolet light, ion bombardment and radical treatment. For temperature sensitive materials, the process temperature is a crucial parameter. Pulsing of the plasma reduces the time average heat strain and also provides additional control of the various sterilization mechanisms. Certain aspects of pulsed plasmas are, however, not yet fully understood. Phase resolved optical emission spectroscopy and time resolved ion energy analysis illustrate that a pulsed ICP ignites capacitively before reaching a stable inductive mode. Time resolved investigations of the post-discharge, after switching off the RF power, show that the plasma boundary sheath in front of a substrate does not fully collapse for the case of hydrogen discharges. This is explained by electron heating through super-elastic collisions with vibrationally excited hydrogen molecules.

  12. The structural and optical properties of black silicon by inductively coupled plasma reactive ion etching

    NASA Astrophysics Data System (ADS)

    Steglich, Martin; Käsebier, Thomas; Zilk, Matthias; Pertsch, Thomas; Kley, Ernst-Bernhard; Tünnermann, Andreas

    2014-11-01

    Black Silicon nanostructures are fabricated by Inductively Coupled Plasma Reactive Ion Etching (ICP-RIE) in a gas mixture of SF6 and O2 at non-cryogenic temperatures. The structure evolution and the dependency of final structure geometry on the main processing parameters gas composition and working pressure are investigated and explained comprehensively. The optical properties of the produced Black Silicon structures, a distinct antireflection and light trapping effect, are resolved by optical spectroscopy and conclusively illustrated by optical simulations of accurate models of the real nanostructures. By that the structure sidewall roughness is found to be critical for an elevated reflectance of Black Silicon resulting from non-optimized etching processes. By analysis of a multitude of structures fabricated under different conditions, approximate limits for the range of feasible nanostructure geometries are derived. Finally, the technological applicability of Black Silicon fabrication by ICP-RIE is discussed.

  13. E→H mode transition density and power in two types of inductively coupled plasma configuration

    SciTech Connect

    Wang, Jian; Du, Yin-chang; Zhang, Xiao; Zheng, Zhe; Liu, Yu; Xu, Liang; Wang, Pi; Cao, Jin-xiang

    2014-07-15

    E → H transition power and density were investigated at various argon pressures in inductively coupled plasma (ICP) in a cylindrical interlaid chamber. The transition power versus the pressure shows a minimum transition power at 4 Pa (ν/ω=1) for argon. Then the transition density hardly changes at low pressures (ν/ω≪1), but it increases clearly when argon pressure exceeds an appropriate value. In addition, both the transition power and transition density are lower in the re-entrant configuration of ICP compared with that in the cylindrical configuration of ICP. The result may be caused from the decrease of stochastic heating in the re-entrant configuration of ICP. This work is useful to understand E → H mode transition and control the transition points in real plasma processes.

  14. Evaluation of precursor evaporation in Si nanoparticle synthesis by inductively coupled thermal plasmas

    NASA Astrophysics Data System (ADS)

    Colombo, V.; Ghedini, E.; Gherardi, M.; Sanibondi, P.

    2013-06-01

    The evaporation of a micro-sized silicon solid precursor in a laboratory scale inductively coupled thermal plasma system for nanoparticle synthesis is investigated numerically using a customized version of the commercial CFD code ANSYS FLUENT©. Two turbulence models—the standard k-ɛ and the Reynolds stress model—and two different models for the computation of vapour production from the heated precursor—evaporation at boiling point and vaporization driven by vapour concentration gradients—are compared. The choice of the turbulence model can considerably influence the estimation of vapour production because plasma temperature reduction by plasma-particle heat exchange is increased when the flow in the torch region is predicted to be laminar, whereas the choice of the model for particle evaporation may be critical when the plasma temperature is decreased by plasma-particle heat exchange to values close to the boiling point of the material treated.

  15. III-Nitride Dry Etching - Comparison of Inductively Coupled Plasma Chemistries

    SciTech Connect

    Abernathy, C.R.; Cho, H.; Donovan, S.M.; Hahn, Y-B.; Han, J.; Hays, D.C.; MacKenzie, J.D.; Pearton, S.J.; Shul, R.J.

    1998-11-10

    A systematic study of the etch characteristics of GaN, AlN and InN has been performed with boron halides- (BI{sub 3} and BBr{sub 3}) and interhalogen- (ICl and IBr) based Inductively Coupled Plasmas. Maximum etch selectivities of -100:1 were achieved for InN over both GaN and AlN in the BI{sub 3} mixtures due to the relatively high volatility of the InN etch products and the lower bond strength of InN. Maximum selectivies of- 14 for InN over GaN and >25 for InN over AlN were obtained with ICl and IBr chemistries. The etched surface morphologies of GaN in these four mixtures are similar or better than those of the control sample.

  16. Numerical Study of a System of Long Josephson Junctions with Inductive and Capacitive Couplings

    NASA Astrophysics Data System (ADS)

    Rahmonov, I. R.; Shukrinov, Yu. M.; Plecenik, A.; Zemlyanaya, E. V.; Bashashin, M. V.

    2016-02-01

    The phase dynamics of the stacked long Josephson junctions is investigated taking into account the inductive and capacitive couplings between junctions and the diffusion current. The simulation of the current-voltage characteristics is based on the numerical solution of a system of nonlinear partial differential equations by a fourth order Runge-Kutta method and finite-difference approximation. A parallel implementation is based on the MPI technique. The effectiveness of the MPI/C++ code is confirmed by calculations on the multi-processor cluster CICC (LIT JINR, Dubna). We demonstrate the appearance of the charge traveling wave (CTW) at the boundary of the zero field step. Based on this fact, we conclude that the CTW and the fluxons coexist.

  17. Automation of preparation of nonmetallic samples for analysis by atomic absorption and inductively coupled plasma spectrometry

    NASA Technical Reports Server (NTRS)

    Wittmann, A.; Willay, G.

    1986-01-01

    For a rapid preparation of solutions intended for analysis by inductively coupled plasma emission spectrometry or atomic absorption spectrometry, an automatic device called Plasmasol was developed. This apparatus used the property of nonwettability of glassy C to fuse the sample in an appropriate flux. The sample-flux mixture is placed in a composite crucible, then heated at high temperature, swirled until full dissolution is achieved, and then poured into a water-filled beaker. After acid addition, dissolution of the melt, and filling to the mark, the solution is ready for analysis. The analytical results obtained, either for oxide samples or for prereduced iron ores show that the solutions prepared with this device are undistinguished from those obtained by manual dissolutions done by acid digestion or by high temperature fusion. Preparation reproducibility and analytical tests illustrate the performance of Plasmasol.

  18. Low-frequency, self-sustained oscillations in inductively coupled plasmas used for optical pumping

    SciTech Connect

    Coffer, J.; Encalada, N.; Huang, M.; Camparo, J.

    2014-10-28

    We have investigated very low frequency, on the order of one hertz, self-pulsing in alkali-metal inductively-coupled plasmas (i.e., rf-discharge lamps). This self-pulsing has the potential to significantly vary signal-to-noise ratios and (via the ac-Stark shift) resonant frequencies in optically pumped atomic clocks and magnetometers (e.g., the atomic clocks now flying on GPS and Galileo global navigation system satellites). The phenomenon arises from a nonlinear interaction between the atomic physics of radiation trapping and the plasma's electrical nature. To explain the effect, we have developed an evaporation/condensation theory (EC theory) of the self-pulsing phenomenon.

  19. Effect of antenna size on electron kinetics in inductively coupled plasmas

    SciTech Connect

    Lee, Hyo-Chang; Chung, Chin-Wook

    2013-10-15

    Spatially resolved measurements of electron energy distribution functions (EEDFs) are investigated in inductively coupled plasmas with two planar antenna coils. When the plasma is sustained by the antenna with a diameter of 18 cm, the nonlocal kinetics is preserved in the argon gas pressure range from 2 mTorr to 20 mTorr. However, electron kinetics transit from nonlocal kinetics to local kinetics in discharge sustained by the antenna coil with diameter 34 cm. The results suggest that antenna size as well as chamber length are important parameters for the transition of the electron kinetics. Spatial variations of plasma potential, effective electron temperature, and EEDF in terms of total electron energy scale are also presented.

  20. Power dependence of electron density at various pressures in inductively coupled plasmas

    SciTech Connect

    Kim, June Young; Kim, Dong-Hwan; Kim, Ju Ho; Jeon, Sang-Bum; Cho, Sung-Won; Chung, Chin-Wook

    2014-11-15

    Experimental observation of the electron density variation in inductively coupled plasmas with the electron energy probability function (EEPFs) was performed at various gas pressures at two RF powers (25 W and 200 W). The measured EEPFs at high power discharges (200 W) showed a Maxwellian distribution, while evolution of the EEPFs from a bi-Maxwellian distribution to a Druyvesteyn-like distribution was observed at low RF powers (25 W) with increasing pressure. A discrepancy of the electron density variation between the two RF powers was observed. This difference is explained by the modified collisional loss and the Bohm velocity from the EEPF of the bi-Maxwellian distribution and the Druyvesteyn–like distribution.

  1. Effect of the electron energy distribution on total energy loss with argon in inductively coupled plasmas

    SciTech Connect

    Kim, June Young; Kim, Young-Cheol; Kim, Yu-Sin; Chung, Chin-Wook

    2015-01-15

    The total energy lost per electron-ion pair lost ε{sub T} is investigated with the electron energy distribution function (EEDF). The EEDFs are measured at various argon powers in RF inductively coupled plasma, and the EEDFs show a depleted distribution (a discontinuity occurring at the minimum argon excitation threshold energy level) with the bulk temperature and the tail temperature. The total energy loss per electron-ion pair lost ε{sub T} is calculated from a power balance model with the Maxwellian EEDFs and the depleted EEDFs and then compared with the measured ε{sub T} from the floating probe. It is concluded that the small population of the depleted high energy electrons dramatically increases the collisional energy loss, and the calculated ε{sub T} from the depleted EEDFs has a value that is similar to the measured ε{sub T}.

  2. A study on plasma parameters in various mixed Ar/SF6 inductively coupled plasma

    NASA Astrophysics Data System (ADS)

    Oh, Seung-Ju; Lee, Hyo-Chang; Chung, Chin-Wook

    2011-10-01

    SF6 gas or Ar/SF6 mixing gas is widely used in plasma processes. However, there are a little experimental study with various external parameters such as gas pressures and mixing ratios. In this work, a study of the plasma parameters was done in Ar/SF6 inductively coupled plasma (ICP) from a careful measurement of the electron energy distribution function (EEDF). The measured plasma parameters are compared to the theoretical results with simplified global model. At a low gas pressure, as mixing ratio of SF6 gas increased at a fixed ICP power, electron density decreased and electron temperature increased, but they were not changed largely. However, a remarkable increase in the electron temperature was observed with decrease in the electron density at higher gas pressures. These changes in the plasma parameters could be explained by large electron losses due to the electron attachment and the experimental results were in agreement with the theoretical results.

  3. Osmium isotopic ratio measurements by inductively coupled plasma source mass spectrometry

    SciTech Connect

    Russ, G.P. III; Bazan, J.M.; Date, A.R.

    1987-04-01

    The isotopic composition of nanogram quantities of osmium was measured by using an inductively coupled plasma source mass spectrometer. Sensitivity was enhanced a factor of approx.100 by the use of an osmium tetraoxide vapor generator rather than nebulization of solution. For samples less than or equal to5 ng, the ratios /sup 190/Os//sup 192/Os, /sup 189/Os//sup 192/Os, and /sup 188/Os//sup 192/Os were determined to better than +/- 0.5% (1sigma/sub m/) precision. For the minor isotopes, the ratios /sup 187/Os//sup 192/Os and /sup 186/Os//sup 192/Os were determined to +/-1%, and /sup 184/Os//sup 192/Os (4 x 10/sup -4/) was determined to approx.10%. Isotope ratios for common osmium are reported.

  4. Pulsed radio-frequency discharge inductively coupled plasma mass spectrometry for oxide analysis

    NASA Astrophysics Data System (ADS)

    Li, Weifeng; Yin, Zhibin; Hang, Wei; Li, Bin; Huang, Benli

    2016-08-01

    A direct solid sampling technique has been developed based on a pulsed radio-frequency discharge (RFD) in mixture of N2 and Ar environment at atmospheric pressure. With an averaged input power of 65 W, a crater with the diameter of 80 μm and depth of 50 μm can be formed on sample surface after discharge for 1 min, suggesting the feasibility of the pulsed RFD for sampling nonconductive solids. Combined with inductively coupled plasma mass spectrometry (ICPMS), this technique allows to measure elemental composition of solids directly with relative standard deviation (RSD) of ~ 20%. Capability of quantitative analysis was demonstrated by the use of soil standards and artificial standards. Good calibration linearity and limits of detection (LODs) in range of 10- 8-10- 9 g/g were achieved for most elements.

  5. Apparatus having inductively coupled coaxial coils for measuring buildup of slay or ash in a furnace

    DOEpatents

    Mathur, Mahendra P.; Ekmann, James M.

    1989-01-01

    The buildup of slag or ash on the interior surface of a furnace wall is monitored by disposing two coils to form a transformer which is secured adjacent to the inside surface of the furnace wall. The inductive coupling between the two coils of the transformer is affected by the presence of oxides of iron in the slag or ash which is adjacent to the transformer, and the application of a voltage to one winding produces a voltage at the other winding that is related to the thickness of the slag or ash buildup on the inside surface of the furnace wall. The output of the other winding is an electrical signal which can be used to control an alarm or the like or provide an indication of the thickness of the slag or ash buildup at a remote location.

  6. Investigation of Asymmetries in Inductively Coupled Plasma Etching Reactors Using a 3-Dimensional Hybrid Model

    NASA Astrophysics Data System (ADS)

    Kushner, Mark J.; Grapperhaus, Michael J.

    1996-10-01

    Inductively Coupled Plasma (ICP) reactors have the potential for scaling to large area substrates while maintaining azimuthal symmetry or side-to-side uniformity across the wafer. Asymmetric etch properties in these devices have been attributed to transmission line properties of the coil, internal structures (such as wafer clamps) and non-uniform gas injection or pumping. To investigate the origins of asymmetric etch properties, a 3-dimensional hybrid model has been developed. The hybrid model contains electromagnetic, electric circuit, electron energy equation, and fluid modules. Continuity and momentum equations are solved in the fluid module along with Poisson's equation. We will discuss results for ion and radical flux uniformity to the substrate while varying the transmission line characteristics of the coil, symmetry of gas inlets/pumping, and internal structures. Comparisons will be made to expermental measurements of etch rates. ^*Work supported by SRC, NSF, ARPA/AFOSR and LAM Research.

  7. Ionization in inductively coupled argon plasmas studied by optical emission spectroscopy

    SciTech Connect

    Lee, Young-Kwang; Chung, Chin-Wook

    2011-01-01

    Contribution of stepwise ionization to total ionization was experimentally investigated in low-pressure inductively coupled argon plasmas. In the pressure range 3-50 mTorr, optical emission spectroscopy was employed to determine metastable fractions (metastable density relative to ground state density) by measuring the emission intensity of selected lines. The measured metastable fractions were in good agreement with the calculation, showing a dependence on the discharge pressure. The rate of stepwise ionization was estimated from the excited level densities (measurements and model predictions) and their ionization rate coefficients. It is observed that at relatively low discharge pressures (<10 mTorr) the ionization is mainly provided by the direct ionization, whereas at higher pressure the stepwise ionization is predominant with increasing absorbed power.

  8. Multi-elemental analysis of aqueous geological samples by inductively coupled plasma-optical emission spectrometry

    USGS Publications Warehouse

    Todorov, Todor I.; Wolf, Ruth E.; Adams, Monique

    2014-01-01

    Typically, 27 major, minor, and trace elements are determined in natural waters, acid mine drainage, extraction fluids, and leachates of geological and environmental samples by inductively coupled plasma-optical emission spectrometry (ICP-OES). At the discretion of the analyst, additional elements may be determined after suitable method modifications and performance data are established. Samples are preserved in 1–2 percent nitric acid (HNO3) at sample collection or as soon as possible after collection. The aqueous samples are aspirated into the ICP-OES discharge, where the elemental emission signals are measured simultaneously for 27 elements. Calibration is performed with a series of matrix-matched, multi-element solution standards.

  9. Assessment of the analytical capabilities of inductively coupled plasma-mass spectrometry

    USGS Publications Warehouse

    Taylor, H.E.; Garbarino, J.R.

    1988-01-01

    A thorough assessment of the analytical capabilities of inductively coupled plasma-mass spectrometry was conducted for selected analytes of importance in water quality applications and hydrologic research. A multielement calibration curve technique was designed to produce accurate and precise results in analysis times of approximately one minute. The suite of elements included Al, As, B, Ba, Be, Cd, Co, Cr, Cu, Hg, Li, Mn, Mo, Ni, Pb, Se, Sr, V, and Zn. The effects of sample matrix composition on the accuracy of the determinations showed that matrix elements (such as Na, Ca, Mg, and K) that may be present in natural water samples at concentration levels greater than 50 mg/L resulted in as much as a 10% suppression in ion current for analyte elements. Operational detection limits are presented.

  10. Determination of elemental content off rocks by laser ablation inductively coupled plasma mass spectrometry

    USGS Publications Warehouse

    Lichte, F.E.

    1995-01-01

    A new method of analysis for rocks and soils is presented using laser ablation inductively coupled plasma mass spectrometry. It is based on a lithium borate fusion and the free-running mode of a Nd/YAG laser. An Ar/N2 sample gas improves sensitivity 7 ?? for most elements. Sixty-three elements are characterized for the fusion, and 49 elements can be quantified. Internal standards and isotopic spikes ensure accurate results. Limits of detection are 0.01 ??g/g for many trace elements. Accuracy approaches 5% for all elements. A new quality assurance procedure is presented that uses fundamental parameters to test relative response factors for the calibration.

  11. Automated standardization technique for an inductively-coupled plasma emission spectrometer

    USGS Publications Warehouse

    Garbarino, J.R.; Taylor, H.E.

    1982-01-01

    The manifold assembly subsystem described permits real-time computer-controlled standardization and quality control of a commercial inductively-coupled plasma atomic emission spectrometer. The manifold assembly consists of a branch-structured glass manifold, a series of microcomputer-controlled solenoid valves, and a reservoir for each standard. Automated standardization involves selective actuation of each solenoid valve that permits a specific mixed standard solution to be pumped to the nebulizer of the spectrometer. Quality control is based on the evaluation of results obtained for a mixed standard containing 17 analytes, that is measured periodically with unknown samples. An inaccurate standard evaluation triggers restandardization of the instrument according to a predetermined protocol. Interaction of the computer-controlled manifold assembly hardware with the spectrometer system is outlined. Evaluation of the automated standardization system with respect to reliability, simplicity, flexibility, and efficiency is compared to the manual procedure. ?? 1982.

  12. Determination of mercury in fish samples by slurry sampling electrothermal vaporization inductively coupled plasma mass spectrometry

    NASA Astrophysics Data System (ADS)

    Liaw, Ming-Jyh; Jiang, Shiuh-Jen; Li, Yi-Ching

    1997-06-01

    Ultrasonic slurry sampling electrothermal vaporization inductively coupled plasma mass spectrometry (USS-ETV-ICP-MS) has been applied to the determination of mercury in several fish samples. The effects of instrument operating conditions and slurry preparation on the ion signals are reported. Palladium was used as modifier to delay the vaporization of mercury in this study. As the vaporization behavior of mercury in fish slurry and aqueous solution is quite different, the standard addition method was used for the determination of mercury in reference materials. The detection limit of mercury estimated from the standard addition curve was in the range 0.002-0.004 μg g -1 for different samples. This method has been applied to the determination of mercury in dogfish muscle reference material (DORM-1 and DORM-2) and dogfish liver reference material (DOLT-1). Accuracy was better than 4% and precision was better than 7% with the USS-ETV-ICP-MS method.

  13. Electron density measurement of inductively coupled plasmas by terahertz time-domain spectroscopy (THz-TDS)

    SciTech Connect

    Ando, Ayumi; Kurose, Tomoko; Kitano, Katsuhisa; Hamaguchi, Satoshi; Reymond, Vivien; Kitahara, Hideaki; Takano, Keisuke; Hangyo, Masanori; Tani, Masahiko

    2011-10-01

    The electron densities of argon inductively coupled plasmas were measured by terahertz time-domain spectroscopy (THz-TDS). At a low pressure, the electron densities were also measured with a Langmuir-type double probe and the validity of THz-TDS electron-density measurement in a plasma has been corroborated. As the input radio-frequency (RF) power increases, the plasma density and gas temperature increase, which makes the probe measurement less reliable or even impossible, due to the large heat load to the probe surface. On the contrary, the THz-TDS measurement is unaffected by the gas temperature and becomes more reliable due to the higher electron density at higher input power for plasma generation.

  14. Inductively-Coupled RF Powered O2 Plasma as a Sterilization Source

    NASA Technical Reports Server (NTRS)

    Sharma, S. P.; Rao, M. V. V. S.; Cruden, B. A.; Meyyappan, M.; Mogul, R.; Khare, B.; Chan, S. L.; Arnold, James O. (Technical Monitor)

    2001-01-01

    Low-temperature or cold plasmas have been shown to be effective for the sterilization of sensitive medical devices and electronic equipment. Low-temperature plasma sterilization procedures possess certain advantages over other protocols such as ethylene oxide, gamma radiation, and heat due to the use of inexpensive reagents, the insignificant environmental impacts and the low energy requirements. In addition, plasmas may also be more efficacious in the removal of robust microorganisms due to their higher chemical reactivity. Together, these attributes render cold plasma sterilization as ideal for the surface decontamination requirements for NASA Planetary Protection. Hence, the work described in this study involves the construction, characterization, and application of an inductively-coupled, RF powered oxygen (O2) plasma.

  15. Stable isotope dilution analysis of hydrologic samples by inductively coupled plasma mass spectrometry

    USGS Publications Warehouse

    Garbarino, J.R.; Taylor, H.E.

    1987-01-01

    Inductively coupled plasma mass spectrometry is employed in the determination of Ni, Cu, Sr, Cd, Ba, Ti, and Pb in nonsaline, natural water samples by stable isotope dilution analysis. Hydrologic samples were directly analyzed without any unusual pretreatment. Interference effects related to overlapping isobars, formation of metal oxide and multiply charged ions, and matrix composition were identified and suitable methods of correction evaluated. A comparability study snowed that single-element isotope dilution analysis was only marginally better than sequential multielement isotope dilution analysis. Accuracy and precision of the single-element method were determined on the basis of results obtained for standard reference materials. The instrumental technique was shown to be ideally suited for programs associated with certification of standard reference materials.

  16. New Applications of Inductively Coupled Plasma-Mass Spectrometry in the Nuclear Industry

    SciTech Connect

    Rob Henry; Dagmar Koller; Phil Marriott

    1998-12-31

    Inductively coupled plasma mass spectrometry (ICP-MS) complements the traditional methods of quantitation of radioactive isotopes. Because of the favorable ionization potential of most actinides and their daughter products, the argon plasma provides a rich, stable source of ions, which are introduced through a plasma-mass spectrometer interface into the mass spectrometer for isotopic separation. Samples are normally introduced in solution, although direct solids analysis has also been achieved using laser ablation of the sample into the argon plasma. Since 1983, improvements in ICP-MS sensitivity have resulted in correspondingly lower mass detection capability. This development has in turn expanded the number of isotopes accessible to measurement at the levels required in the nuclear industry.

  17. Multielement analysis of deep-sea sediments by inductively coupled plasma mass spectrometry

    NASA Astrophysics Data System (ADS)

    Xia, Ning; Wu, Zhaohui; Guo, Dongfa; Yao, De

    2008-05-01

    Marine sediments were dissolved by HNO3-HF-HClO4 in a sealed container at low pressure; HF was evaporated in an open container and salts were dissolved in HCl by heating, then transferred to 2% HNO3 solution. A total of 45 elements, including Li, Be, Sc, Ti, V, Cr, Mn, Co, Ni, Cu, Zn, Ga, Rb, Sr, Y, Zr, Nb, Mo, Cd, In, Sb, Cs, Ba, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Hf, Ta, W, Tl, Pb, Bi, Th and U, were measured by inductively coupled plasma mass spectrometry (ICP-MS). Conditions and sample experiments showed that this procedure defines a good experimental method which has the advantages of clear interference, easy operation and reliable results. The concentrations of the 45 elements could be used for resource exploration, environmental assessment and academic research.

  18. Trace elemental composition of curry by inductively coupled plasma optical emission spectrometry (ICP-OES).

    PubMed

    Gonzálvez, A; Armenta, S; De La Guardia, M

    2008-01-01

    A methodology based on inductively coupled plasma optical emission spectrometry (ICP-OES) after microwave-assisted acid digestion was developed to determine the content of traces elements in curry samples from the Spanish market. The methodology was validated in terms of accuracy by the analysis of citrus and tomato leaf reference materials achieving comparable results with the certified values. The trace metal content of curry samples was compared with data available from previously published reports concerning Indian samples, especially in terms of heavy metal composition, in order to guarantee the quality of the commercially available spices in the European countries. Values found for the analysis of arsenic, lead and cadmium were significantly lower than the maximum limit allowed by European Union statutory limits for heavy metals and lower than those obtained for Indian curry leaves reported by Indian research teams by using neutron activation and γ-ray analysis. PMID:24784807

  19. Study of uranium matrix interference on ten analytes using inductively coupled plasma atomic emission spectrometry

    NASA Astrophysics Data System (ADS)

    Ghazi, A. A.; Qamar, Sajid; Atta, M. A.

    1993-08-01

    Maximum allowable concentrations of 12 elements in uranium hexafluoride feed for enrichment to reactor grade material (about 3%), vary from 1 to 100 ppm ( μg/g). Using an inductively coupled plasma atomic emission spectrometer, 51 lines of ten of these elements (B, Cr, Mo, P, Sb, Si, Ta, Ti, V and W) have been studied with a uranium matrix to investigate the matrix interference on the basis of signal to background (SBR), and background to background ratios (BBR). Detection limits and limits of quantitative determination (LQDs) were calculated for these elements in a uranium matrix using SBR and relative standard deviation of the background signal (RSD B) approach. In almost all cases, the uranium matrix interference reduces the SBRs to the extent that direct trace analysis is impossible. A uranium sample having known concentrations of impurities (around LQDs) was directly analysed with results that showed reasonable accuracy and precision.

  20. Accurate determination of silver nanoparticles in animal tissues by inductively coupled plasma mass spectrometry

    NASA Astrophysics Data System (ADS)

    Veverková, Lenka; Hradilová, Šárka; Milde, David; Panáček, Aleš; Skopalová, Jana; Kvítek, Libor; Petrželová, Kamila; Zbořil, Radek

    2014-12-01

    This study examined recoveries of silver determination in animal tissues after wet digestion by inductively coupled plasma mass spectrometry. The composition of the mineralization mixture for microwave assisted digestion was optimized and the best recoveries were obtained for mineralization with HNO3 and addition of HCl promptly after digestion. The optimization was performed on model samples of chicken meat spiked with silver nanoparticles and a solution of ionic silver. Basic calculations of theoretical distribution of Ag among various silver-containing species were implemented and the results showed that most of the silver is in the form of soluble complexes AgCl2- and AgCl32 - for the optimized composition of the mineralization mixture. Three animal tissue certified reference materials were then analyzed to verify the trueness and precision of the results.

  1. Measurement of neutral gas temperature in a 13.56 MHz inductively coupled plasma

    SciTech Connect

    Jayapalan, Kanesh K.; Chin, Oi Hoong

    2015-04-24

    Measuring the temperature of neutrals in inductively coupled plasmas (ICP) is important as heating of neutral particles will influence plasma characteristics such as the spatial distributions of plasma density and electron temperature. Neutral gas temperatures were deduced using a non-invasive technique that combines gas actinometry, optical emission spectroscopy and simulation which is described here. Argon gas temperature in a 13.56 MHz ICP were found to fall within the range of 500 − 800 K for input power of 140 − 200 W and pressure of 0.05 − 0.2 mbar. Comparing spectrometers with 0.2 nm and 0.5 nm resolution, improved fitting sensitivity was observed for the 0.2 nm resolution.

  2. Etching characteristics of LiNbO3 in reactive ion etching and inductively coupled plasma

    NASA Astrophysics Data System (ADS)

    Ren, Z.; Heard, P. J.; Marshall, J. M.; Thomas, P. A.; Yu, S.

    2008-02-01

    The etching characteristics of congruent LiNbO3 single crystals including doped LiNbO3 and proton-changed LiNbO3 have been studied in reactive ion etching (RIE) and inductively coupled plasma (ICP) etching tools, using different recipes of gas mixtures. The effects of parameters including working pressure, RIE power, and ICP power are investigated and analyzed by measurement of etching depth, selectivity, uniformity, etched surface state, and sidewall profile by means of focused ion beam etching, energy-dispersive x-ray analysis, secondary ion mass spectroscopy, scanning electron microscopy, and surface profilometry. The effects of a sample carrier wafer coating have also been investigated. Optimized processes with high etching rates, good mask selectivity, and a near-vertical profile have been achieved. Ridge waveguides on proton-exchanged LiNbO3 have been fabricated and optically measured.

  3. Current-free double-layer formation in inductively coupled plasma in a uniform magnetic field

    SciTech Connect

    Popescu, S.; Ohtsu, Y.; Fujita, H.

    2006-06-15

    The axial profiles of plasma parameters for low and moderate pressures, such as the plasma potential, electron temperature, and number density, have been evaluated in magnetized inductively coupled plasma. The experimental results revealed in both cases the existence of a genuine current-free double-layer structure, separating two plasma regions with different properties. Based on the experimental results, a physical scenario for the self-assembling of the double layer is proposed. Also, the axial profile of the electron number density downstream is analyzed, emphasizing the role of neutral metastable ionization, and a simple analytical model is developed to fit the experimental data. The model allows the estimation of neutral metastable number density downstream and the recombination rate coefficient.

  4. Inductively coupled plasma-atomic emission spectrometry (ICP-AES) in support of nuclear waste management

    NASA Astrophysics Data System (ADS)

    Huff, Edmund A.; Horwitz, E. Philip

    Simulated complex nuclear waste solutions are characterized by inductively coupled plasma-atomic emission spectrometry (ICP-AES). Simultaneous and sequential measurements are made of liquid extraction distribution coefficients needed in the development of process flow sheets for component separations. This paper describes the determination of 19 elements, comprised of process contaminants (Al, Cr, Fe, Ni) and nuclear fission products (Ba, Cd, Ce, Eu, La, Mo, Nd, Pd, Pr, Rh, Ru, Sm, Sr, Y, Zr), in diverse aqueous streams. The concentrations determined vary from 0.04 to 4000μg ml -1 with dilutions being used to bring analytical measurements into the range of calibration standards. The estimated precision and accuracy of the method are 1-5 %. Data are presented on recoveries and material balances for extraction systems that can be used for the implementation of actinide (III)-fission product separation schemes.

  5. Expressing self-absorption in the analytical function of inductively coupled plasma atomic emission spectrometry

    NASA Astrophysics Data System (ADS)

    Kántor, Tibor; Bartha, András

    2015-11-01

    The self-absorption of spectral lines was studied with up to date multi-element inductively coupled plasma atomic emission spectrometry (ICP-AES) instrumentation using radial and axial viewing of the plasma, as well, performing line peak height and line peak area measurements. Two resonance atomic and ionic lines of Cd and Mg were studied, the concentration range was extended up to 2000 mg/L. At the varying analyte concentration, constant matrix concentration of 10,000 mg/L Ca was ensured in the pneumatically nebulized solutions. The physical and the phenomenological formulation of the emission analytical function is overviewed and as the continuity of the earlier results the following equation is offered:

  6. Characteristics of Plasma Using a Ferromagnetic Enhanced Inductively Coupled Plasma Source

    NASA Astrophysics Data System (ADS)

    Kim, Kyong Nam; Hyeuk Lim, Jong; Park, Jung Kyun; Lim, Jong Tae; Yeom, Geun Young

    2008-09-01

    Plasma characteristics and electrical parameters of an internal linear inductively coupled plasma (ICP) source with a U-type antenna with/without a Ni-Zn ferromagnetic material installed near the antenna were investigated. The application of the ferromagnetic material to the antenna increased the plasma density, improved the plasma uniformity, lowered the antenna voltage, and increased the stability of the plasma during the operation. For the U-type ferromagnetic enhanced internal linear ICP source, a high density plasma on the order of 4.5×1011 cm-3 which is about three higher than that obtained for the source without the ferromagnetic material could be obtained at the pressure of 10 mTorr Ar and at the RF power of 600 W at 13.56 MHz.

  7. Uniformity of internal linear-type inductively coupled plasma source for flat panel display processing

    NASA Astrophysics Data System (ADS)

    Lim, Jong Hyeuk; Kim, Kyong Nam; Park, Jung Kyun; Lim, Jong Tae; Yeom, Geun Young

    2008-02-01

    The variation in plasma uniformity over an extremely large size inductively coupled plasma (ICP) source of 2750×2350mm2 was examined. An internal linear-type antenna called "double comb-type antenna" was used as the ICP source. A plasma density of ˜1.4×1011/cm3 could be obtained at 5mTorr Ar by applying 10kW rf power to the source at a frequency of 13.56MHz. An increase in rf power from 1to10kW improved the plasma uniformity over a substrate area of 2300×2000mm2 from 18.1% to 11.4%. The improvement in uniformity of the internal ICP source was attributed to the increase in plasma density near the wall.

  8. Neutralization efficiency estimation in a neutral beam source based on inductively coupled plasma

    NASA Astrophysics Data System (ADS)

    Vozniy, O. V.; Yeom, G. Y.

    2009-01-01

    This study examined the optimal conditions of neutral beam generation to maintain a high degree of neutralization and focusing during beam energy variation for a neutral beam source based on inductively coupled plasma with a three-grid ion beam acceleration system. The neutral beam energy distribution was estimated by measuring the energy profiles of ions that "survived" the neutralization after reflection. The energy measurements of the primary and reflected ions showed narrow distribution functions, each with only one peak. At higher beam energies, both the ratio of the ion energy loss to the primary energy and the degree of energy divergence decreased, confirming the precise alignment of the neutral beam. The neutralization efficiency of the neutral beam source with a three-grid acceleration system was found to be affected mainly by the beam angle divergence rather than by the particle translation energy.

  9. Anisotropic Ta{sub 2}O{sub 5} waveguide etching using inductively coupled plasma etching

    SciTech Connect

    Muttalib, Muhammad Firdaus A. Chen, Ruiqi Y.; Pearce, Stuart J.; Charlton, Martin D. B.

    2014-07-01

    Smooth and vertical sidewall profiles are required to create low loss rib and ridge waveguides for integrated optical device and solid state laser applications. In this work, inductively coupled plasma (ICP) etching processes are developed to produce high quality low loss tantalum pentoxide (Ta{sub 2}O{sub 5}) waveguides. A mixture of C{sub 4}F{sub 8} and O{sub 2} gas are used in combination with chromium (Cr) hard mask for this purpose. In this paper, the authors make a detailed investigation of the etch process parameter window. Effects of process parameters such as ICP power, platen power, gas flow, and chamber pressure on etch rate and sidewall slope angle are investigated. Chamber pressure is found to be a particularly important factor, which can be used to tune the sidewall slope angle and so prevent undercut.

  10. Alleviation of overlap interferences for determination of potassium isotope ratios by inductively coupled plasma mass spectrometry

    SciTech Connect

    Jiang, S.J.; Houk, R.S.; Stevens, M.A.

    1988-06-01

    Positioning the sampling orifice relatively far from the load coil combined with use of low forward power and high aerosol gas flow rate causes the background mass spectrum to become dominated by NO/sup +/. Nearly all the Ar/sup +/ and ArH/sup +/ ions are suppressed under these conditions, which frees m/z 39 and 41 for potassium isotope ratio measurements. The precision is 0.3-0.9% relative standard deviation for potassium concentrations in the range 1-50 mg L/sup -1/. The determined ratios are approx. 9% higher than the accepted value and also vary with the concentration of sodium concomitant, so calibrations and chemical separations are desirable. These observations should permit use of inductively coupled plasma mass spectrometry for rapid isotope ratio determinations of potassium from biological organisms or water sources.

  11. Laser ablation inductively coupled plasma mass spectrometry measurement of isotope ratios in depleted uranium contaminated soils.

    PubMed

    Seltzer, Michael D

    2003-09-01

    Laser ablation of pressed soil pellets was examined as a means of direct sample introduction to enable inductively coupled plasma mass spectrometry (ICP-MS) screening of soils for residual depleted uranium (DU) contamination. Differentiation between depleted uranium, an anthropogenic contaminant, and naturally occurring uranium was accomplished on the basis of measured 235U/238U isotope ratios. The amount of sample preparation required for laser ablation is considerably less than that typically required for aqueous sample introduction. The amount of hazardous laboratory waste generated is diminished accordingly. During the present investigation, 235U/238U isotope ratios measured for field samples were in good agreement with those derived from gamma spectrometry measurements. However, substantial compensation was required to mitigate the effects of impaired pulse counting attributed to sample inhomogeneity and sporadic introduction of uranium analyte into the plasma. PMID:14611049

  12. Inductively coupled plasma optical emission spectroscopy determination of trace element composition of argan oil.

    PubMed

    Gonzálvez, A; Ghanjaoui, M E; El Rhazi, M; de la Guardia, M

    2010-02-01

    A methodology based on inductively coupled plasma optical emission spectroscopy (ICP-OES) after microwave assisted acid digestion has been developed to determine the trace element content of Moroccan argan oil. Limit of detection values equal or lower than few mg/kg were obtained for all elements under study. To assure the accuracy of the whole procedure, recovery studies were carried out on argan oil samples spiked at different concentration levels from 10 to 200 µg/L. Quantitative average recovery values were obtained for all elements evaluated, demonstrating the suitability of this methodology for the determination of trace elements in argan oil samples. Aluminum, calcium, chromium, iron, potassium, lithium, magnesium, sodium, vanadium and zinc were quantitatively determined in Moroccan argan oils being found that their concentration is different of that found in other edible oils thus offering a way for authentication and for the evaluation of possible adulterations. PMID:21339122

  13. A comprehensive study of different gases in inductively coupled plasma torch operating at one atmosphere

    SciTech Connect

    Punjabi, Sangeeta B.; Joshi, N. K.; Mangalvedekar, H. A.; Lande, B. K.; Das, A. K.; Kothari, D. C.

    2012-01-15

    A numerical study is done to understand the possible operating regimes of RF-ICP torch (3 MHz, 50 kW) using different gases for plasma formation at atmospheric pressure. A two dimensional numerical simulation of RF-ICP torch using argon, nitrogen, oxygen, and air as plasma gas has been investigated using computational fluid dynamic (CFD) software fluent{sup (c)}. The operating parameters varied here are central gas flow, sheath gas flow, RF-power dissipated in plasma, and plasma gas. The temperature contours, flow field, axial, and radial velocity profiles were investigated under different operating conditions. The plasma resistance, inductance of the torch, and the heat distribution for various plasma gases have also been investigated. The plasma impedance of ICP torch varies with different operating parameters and plays an important role for RF oscillator design and power coupling. These studies will be useful to decide the design criteria for ICP torches required for different material processing applications.

  14. Synthesis of Ozone at Atmospheric Pressure by a Quenched Induction-Coupled Plasma Torch

    SciTech Connect

    A. Blutke; B.C. Stratton; D.R. Mikkelsen; J. Vavruska; R. Knight

    1998-01-01

    The technical feasibility of using an induction-coupled plasma (ICP) torch to synthesize ozone at atmospheric pressure is explored. Ozone concentrations up to ~250 ppm were produced using a thermal plasma reactor system based on an ICP torch operating at 2.5 MHz and ~11 kVA with an argon/oxygen mixture as the plasma-forming gas. A gaseous oxygen quench formed ozone by rapid mixing of molecular oxygen with atomic oxygen produced by the torch. The ozone concentration in the reaction chamber was measured by Fourier Transform infrared (FTIR) spectroscopy over a wide range of experimental configurations. The geometry of the quench gas flow, the quench flow velocity, and the quench flow rate played important roles in determining the ozone concentration. The ozone concentration was sensitive to the torch RF power, but was insensitive to the torch gas flow rates. These observations are interpreted within the framework of a simple model of ozone synthesis.

  15. Laser Irradiation of Aqueous Solutions for Application in Inductively Coupled Plasma Spectrometry

    NASA Astrophysics Data System (ADS)

    Su, H.; Xu, L.; Chen, J.; Li, X.; Wang, Y.

    2016-01-01

    The sensitivity of detection of trace heavy metal elements in water samples by inductively coupled plasma (ICP) spectrometry has been improved applying a 10.6 μm infrared laser to irradiate the aqueous solution. With optimal laser power density and irradiation time, the surface tension and viscosity of the aqueous solution were reduced by 38.09 and 11.35%, respectively. The nebulization efficiency of the processed solution in ICP was increased by 47.14%. The spectral intensity and signal-to-noise ratio (SNR) of the trace heavy metal elements including As, Cd, Cr, Cu, Hg, and Pb in the treated aqueous solution were both increased. Our experiment demonstrated that irradiation using an infrared laser at 10.6 μm is a simple and effective method to improve the detection sensitivity of ICP spectrometry for trace heavy metal elements.

  16. [A genetic algorithm approach to qualitative analysis in inductively coupled plasma-atomic emission spectroscopy].

    PubMed

    Peng, Bin; Liu, Ke-ling; Li, Zhi-min; Wang, Yue-song; Huang, Tu-jiang

    2002-06-01

    Genetic algorithm (GA) is used in automatic qualitative analysis by a sequential inductively coupled plasma spectrometer (ICP-AES) and a computer program is developed in this paper. No any standard samples are needed, and spectroscopic interferences can be eliminated. All elements and their concentration ranges of an unknown sample can be reported. The replication rate Pr, crossover rate Pc, and mutation rate of the genetic algorithm were adjusted to be 0.6, 0.4 and 0 respectively. The analytical results of GA are in good agreement with the reference values. It indicates that, combined with the intensity information, the GA can be applied to spectroscopic qualitative analysis and expected to become an effective method in qualitative analysis in ICP-AES after further work. PMID:12938334

  17. Inductively coupled plasma etching of HgCdTe IRFPAs detectors at cryogenic temperature

    NASA Astrophysics Data System (ADS)

    Chen, Y. Y.; Ye, Z. H.; Sun, C. H.; Zhang, S.; Hu, X. N.; Ding, R. J.; He, L.

    2016-05-01

    To fabricate various advanced structures with HgCdTe material, the Inductively Coupled Plasma enhanced Reactive Ion Etching system is indispensable. However, due to low damage threshold and complicated behaviors of mercury in HgCdTe, the lattice damage and induced electrical conversion is very common. According to the diffusion model during etching period, the mercury interstitials, however, may not diffuse deep into the material at cryogenic temperature. In this report, ICP etching of HgCdTe at cryogenic temperature was implemented. The etching system with cryogenic assembly is provided by Oxford Instrument. The sample table was cooled down to 123K with liquid nitrogen. The mask of SiO2 with a contact layer of ZnS functioned well at this temperature. The selectivity and etching velocity maintained the same as reported in the etching of room temperature. Smooth and clean surfaces and profiles were achieved with an optimized recipe.

  18. Heavy metals in aromatic spices by inductively coupled plasma-mass spectrometry.

    PubMed

    Bua, Daniel Giuseppe; Annuario, Giovanni; Albergamo, Ambrogina; Cicero, Nicola; Dugo, Giacomo

    2016-09-01

    Objective of this study was to determine the content of Cd, Hg, As and Pb in common spices traded in the Italian market, using inductively coupled plasma-mass spectrometry (ICP-MS). The results were compared with the maximum limits established by the national Legislative Decree (LD) no. 107 implementing the Council Directive 88/388/EEC and by international organisations, such as Food and Agriculture Organization (FAO) and World Health Organization (WHO). Food safety for spices was assessed considering the tolerable weekly intake (TWI) and the provisional tolerable weekly intake (PTWI), respectively, for Cd and Hg and the 95% lower confidence limit of the benchmark dose of 1% extra risk (BMDL01) for As and Pb. Investigated elements in all samples were within the maximum limits as set by the national and international normative institutions. Nevertheless, the heavy metal content of some spices exceeded the PTWI, TWI and BMDL01, which needs attention when considering consumer's health. PMID:27074712

  19. Neutralization efficiency estimation in a neutral beam source based on inductively coupled plasma

    SciTech Connect

    Vozniy, O. V.; Yeom, G. Y.

    2009-01-01

    This study examined the optimal conditions of neutral beam generation to maintain a high degree of neutralization and focusing during beam energy variation for a neutral beam source based on inductively coupled plasma with a three-grid ion beam acceleration system. The neutral beam energy distribution was estimated by measuring the energy profiles of ions that 'survived' the neutralization after reflection. The energy measurements of the primary and reflected ions showed narrow distribution functions, each with only one peak. At higher beam energies, both the ratio of the ion energy loss to the primary energy and the degree of energy divergence decreased, confirming the precise alignment of the neutral beam. The neutralization efficiency of the neutral beam source with a three-grid acceleration system was found to be affected mainly by the beam angle divergence rather than by the particle translation energy.

  20. Homogeneous nanocrystalline cubic silicon carbide films prepared by inductively coupled plasma chemical vapor deposition.

    PubMed

    Cheng, Qijin; Xu, S; Long, Jidong; Huang, Shiyong; Guo, Jun

    2007-11-21

    Silicon carbide films with different carbon concentrations x(C) have been synthesized by inductively coupled plasma chemical vapor deposition from a SiH(4)/CH(4)/H(2) gas mixture at a low substrate temperature of 500 °C. The characteristics of the films were studied by x-ray photoelectron spectroscopy, x-ray diffraction, scanning electron microscopy, high-resolution transmission electron microscopy, Fourier transform infrared absorption spectroscopy, and Raman spectroscopy. Our experimental results show that, at x(C) = 49 at.%, the film is made up of homogeneous nanocrystalline cubic silicon carbide without any phase of silicon, graphite, or diamond crystallites/clusters. The average size of SiC crystallites is approximately 6 nm. At a lower value of x(C), polycrystalline silicon and amorphous silicon carbide coexist in the films. At a higher value of x(C), amorphous carbon and silicon carbide coexist in the films. PMID:21730481

  1. Sorption concentration and inductively coupled plasma determination of Mo, V, Zr, and Cr in sea water

    SciTech Connect

    Shcherbinina, N.I.; Ishmiyarova, G.P.; Myasoedova, G.V.

    1992-02-10

    Sorption on complex-forming sorbents is an expanding method for the concentration of microelements for water analysis. The adsorbed elements can be determined directly in the concentrate, in the eluate after desorption or in the residue after decomposition of the sorbent. Among the methods used to determine the elements is atomic emission spectrometry from an inductively coupled plasma (ICP). This method is often used to determine relatively easily desorbed metals. In the present work, the authors investigate the concentration of Mo, V, Zr, and Cr(VI) with the complex forming sorbent POLIORGS VII M and their subsequent determination of ICP. These hard to desorb metals are put back into solution by the rapid microwave decomposition of the sorbent/concentrate with a HNO{sub 3}/H{sub 2}O{sub 2} mixture. The developed method for the determination of Mo, V, Zr, and Cr(VI) was used to analyze sea water. 14 refs., 1 fig., 6 tabs.

  2. Effect of the electron energy distribution on total energy loss with argon in inductively coupled plasmas

    NASA Astrophysics Data System (ADS)

    Kim, June Young; Kim, Young-Cheol; Kim, Yu-Sin; Chung, Chin-Wook

    2015-01-01

    The total energy lost per electron-ion pair lost ɛT is investigated with the electron energy distribution function (EEDF). The EEDFs are measured at various argon powers in RF inductively coupled plasma, and the EEDFs show a depleted distribution (a discontinuity occurring at the minimum argon excitation threshold energy level) with the bulk temperature and the tail temperature. The total energy loss per electron-ion pair lost ɛT is calculated from a power balance model with the Maxwellian EEDFs and the depleted EEDFs and then compared with the measured ɛT from the floating probe. It is concluded that the small population of the depleted high energy electrons dramatically increases the collisional energy loss, and the calculated ɛT from the depleted EEDFs has a value that is similar to the measured ɛT.

  3. A volume averaged global model for inductively coupled HBr/Ar plasma discharge

    NASA Astrophysics Data System (ADS)

    Chung, Sang-Young; Kwon, Deuk-Chul; Choi, Heechol; Song, Mi-Young

    2015-09-01

    A global model for inductively coupled HBr/Ar plasma was developed. The model was based on a self-consistent global model had been developed by Kwon et al., and a set of chemical reactions in the HBr/Ar plasma was compiled by surveying theoretical, experimental and evaluative researches. In this model vibrational excitations of bi-atomic molecules and electronic excitations of hydrogen atom were taken into account. Neutralizations by collisions between positive and negative ions were considered with Hakman's approximate formula achieved by fitting of theoretical result. For some reactions that were not supplied from literatures the reaction parameters of Cl2 and HCl were adopted as them Br2 and HBr, respectively. For validation calculation results using this model were compared with experimental results from literatures for various plasma discharge parameters and it showed overall good agreement.

  4. Fabrication of resonator-quantum well infrared photodetector focal plane array by inductively coupled plasma etching

    NASA Astrophysics Data System (ADS)

    Sun, Jason; Choi, Kwong-Kit

    2016-02-01

    Inductively coupled plasma (ICP) etching has distinct advantages over reactive ion etching in that the etching rates are considerably higher, the uniformity is much better, and the sidewalls of the etched material are highly anisotropic due to the higher plasma density and lower operating pressure. Therefore, ICP etching is a promising process for pattern transfer required during microelectronic and optoelectronic fabrication. Resonator-quantum well infrared photodetectors (R-QWIPs) are the next generation of QWIP detectors that use resonances to increase the quantum efficiency (QE). To fabricate R-QWIP focal plane arrays (FPAs), two optimized ICP etching processes are developed. Using these etching techniques, we have fabricated R-QWIP FPAs of several different formats and pixel sizes with the required dimensions and completely removed the substrates of the FPAs. Their QE spectra were tested to be 30 to 40%. The operability and spectral nonuniformity of the FPA is ˜99.5 and 3%, respectively.

  5. Inductively Coupled Plasma: Fundamental Particle Investigations with Laser Ablation and Applications in Magnetic Sector Mass Spectrometry

    SciTech Connect

    Saetveit, Nathan Joe

    2008-01-01

    Particle size effects and elemental fractionation in laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) are investigated with nanosecond and femtosecond laser ablation, differential mobility analysis, and magnetic sector ICP-MS. Laser pulse width was found to have a significant influence on the LA particle size distribution and the elemental composition of the aerosol and thus fractionation. Emission from individual particles from solution nebulization, glass, and a pressed powder pellet are observed with high speed digital photography. The presence of intact particles in an ICP is shown to be a likely source of fractionation. A technique for the online detection of stimulated elemental release from neural tissue using magnetic sector ICP-MS is described. Detection limits of 1 μg L-1 or better were found for P, Mn, Fe, Cu, and Zn in a 60 μL injection in a physiological saline matrix.

  6. Diagnostics of Argon Inductively Coupled Plasma and Dielectric Barrier Discharge Plasma by Optical Emission Spectroscopy

    NASA Astrophysics Data System (ADS)

    Zhang, Jia-liang; Yu, Shi-ji; Ma, Teng-cai; Deng, Xin-lu

    2001-08-01

    An experimental setup was built up to carry out radio frequency (RF) inductively coupled plasma (ICP) and dielectric barrier discharge (DBD), and to depict the optical emission spectra (OES) of the discharges. OES from argon ICP and DBD plasmas in visible and near ultraviolet region were measured. For argon ICP, the higher RF power input (higher than 500 W for our machine), the higher degree of argon plasma ionization. But that doesn't mean a higher mean electron energy. With the increase in the power input, the mean electron energy increases slightly, whereas the density of electron increases apparently. Or, the contrary, argon DBD discharge behaves in the manner of a pulsed DC discharge on optical emission spectroscopy and V-I characteristics. DBD current is composed of a series of pulses equally spaced in temporal domain. The kinetics of DBD emission strength is mainly governed by the frequency of the current pulse.

  7. Inductively Coupled Plasma-Induced Etch Damage of GaN p-n Junctions

    SciTech Connect

    SHUL,RANDY J.; ZHANG,LEI; BACA,ALBERT G.; WILLISON,CHRISTI LEE; HAN,JUNG; PEARTON,S.J.; REN,F.

    1999-11-03

    Plasma-induced etch damage can degrade the electrical and optical performance of III-V nitride electronic and photonic devices. We have investigated the etch-induced damage of an Inductively Coupled Plasma (ICP) etch system on the electrical performance of mesa-isolated GaN pn-junction diodes. GaN p-i-n mesa diodes were formed by Cl{sub 2}/BCl{sub 3}/Ar ICP etching under different plasma conditions. The reverse leakage current in the mesa diodes showed a strong relationship to chamber pressure, ion energy, and plasma flux. Plasma induced damage was minimized at moderate flux conditions ({le} 500 W), pressures {ge}2 mTorr, and at ion energies below approximately -275 V.

  8. Modeling and simulation of ion-filtered inductively coupled plasma using argon plasma

    NASA Astrophysics Data System (ADS)

    Wu, Chao; Wang, Jian; Zhang, Weiwang; Luo, Yi

    2015-03-01

    An ion-filtered inductively coupled plasma (IF-ICP) is proposed to reduce ion bombardment and provide high metastable species density for chemical vapor deposition. Argon plasma, which has simple reaction mechanism, is simulated to show the effects of ion filter. Compared to typical ICP, the maximum density of ions of IF-ICP is lower while that of metastable species is higher. The filter can absorb ions effectively and relatively small amount of metastable species, with the absorption coefficient proportional to its surface area. A proper gap between filter and substrate can achieve more metastable species and less ions on the substrate. The pressure and RF power need to be optimized based on the tradeoff between deposition rate and ion damage. The density of ions on the substrate can be reduced by two orders of magnitude while that of metastable species are maintained in the order of 1017 m-3 under the optimized conditions.

  9. Ignition delay of a pulsed inductively coupled plasma (ICP) in tandem with an auxiliary ICP

    NASA Astrophysics Data System (ADS)

    Liu, Lei; Sridhar, Shyam; Donnelly, Vincent M.; Economou, Demetre J.

    2015-12-01

    Plasma ignition delays were observed in a ‘main’ inductively coupled plasma (ICP), in tandem with an ‘auxiliary’ ICP. The Faraday-shielded ICPs were separated by a grounded metal grid. Power (13.56 MHz) to the main ICP was pulsed with a frequency of 1 kHz, while the auxiliary ICP was operated in continuous wave (cw) mode. In chlorine plasmas, ignition delay was observed for duty cycles greater than 60% and, in contrast to expectation, the delay was longer with increasing duty cycle up to ~99.5%. The ignition delay could be varied by changing the auxiliary and/or main ICP power. Langmuir probe measurements provided the temporal evolution of electron temperature, and electron and positive ion densities. These measurements revealed that the plasma was ignited shortly after the decaying positive ion density (n +), in the afterglow of the main ICP, reached the density ({{n}+},\\text{aux} ) prevailing when only the auxiliary ICP was powered. At that time, production of electrons began to dominate their loss in the main ICP, due to hot electron injection from the auxiliary ICP. As a result, {{n}\\text{e}} increased from a value below {{n}\\text{e,\\text{aux}}} , improving inductive power coupling efficiency, further increasing plasma density leading to plasma ignition. Plasma ignition delay occurred when the afterglow of the pulsed plasma was not long enough for the ion density to reach {{n}+},\\text{aux} during the afterglow. Besides Cl2, plasma ignition delays were also observed in other electronegative gases (SF6, CF4/O2 and O2) but not in an electropositive gas (Ar).

  10. Tin removal from extreme ultraviolet collector optics by inductively coupled plasma reactive ion etching

    SciTech Connect

    Shin, H.; Srivastava, S. N.; Ruzic, D. N.

    2008-05-15

    Tin (Sn) has the advantage of delivering higher conversion efficiency compared to other fuel materials (e.g., Xe or Li) in an extreme ultraviolet (EUV) source, a necessary component for the leading next generation lithography. However, the use of a condensable fuel in a lithography system leads to some additional challenges for maintaining a satisfactory lifetime of the collector optics. A critical issue leading to decreased mirror lifetime is the buildup of debris on the surface of the primary mirror that comes from the use of Sn in either gas discharge produced plasma (GDPP) or laser produced plasma (LPP). This leads to a decreased reflectivity from the added material thickness and increased surface roughness that contributes to scattering. Inductively coupled plasma reactive ion etching with halide ions is one potential solution to this problem. This article presents results for etch rate and selectivity of Sn over SiO{sub 2} and Ru. The Sn etch rate in a chlorine plasma is found to be much higher (of the order of hundreds of nm/min) than the etch rate of other materials. A thermally evaporated Sn on Ru sample was prepared and cleaned using an inductively coupled plasma etching method. Cleaning was confirmed using several material characterization techniques. Furthermore, a collector mock-up shell was then constructed and etching was performed on Sn samples prepared in a Sn EUV source using an optimized etching recipe. The sample surface before and after cleaning was analyzed by atomic force microscopy, x-ray photoelectron spectroscopy, and Auger electron spectroscopy. The results show the dependence of etch rate on the location of Sn samples placed on the collector mock-up shell.

  11. Analysis of non-equilibrium phenomena in inductively coupled plasma generators

    NASA Astrophysics Data System (ADS)

    Zhang, W.; Lani, A.; Panesi, M.

    2016-07-01

    This work addresses the modeling of non-equilibrium phenomena in inductively coupled plasma discharges. In the proposed computational model, the electromagnetic induction equation is solved together with the set of Navier-Stokes equations in order to compute the electromagnetic and flow fields, accounting for their mutual interaction. Semi-classical statistical thermodynamics is used to determine the plasma thermodynamic properties, while transport properties are obtained from kinetic principles, with the method of Chapman and Enskog. Particle ambipolar diffusive fluxes are found by solving the Stefan-Maxwell equations with a simple iterative method. Two physico-mathematical formulations are used to model the chemical reaction processes: (1) A Local Thermodynamics Equilibrium (LTE) formulation and (2) a thermo-chemical non-equilibrium (TCNEQ) formulation. In the TCNEQ model, thermal non-equilibrium between the translational energy mode of the gas and the vibrational energy mode of individual molecules is accounted for. The electronic states of the chemical species are assumed in equilibrium with the vibrational temperature, whereas the rotational energy mode is assumed to be equilibrated with translation. Three different physical models are used to account for the coupling of chemistry and energy transfer processes. Numerical simulations obtained with the LTE and TCNEQ formulations are used to characterize the extent of non-equilibrium of the flow inside the Plasmatron facility at the von Karman Institute. Each model was tested using different kinetic mechanisms to assess the sensitivity of the results to variations in the reaction parameters. A comparison of temperatures and composition profiles at the outlet of the torch demonstrates that the flow is in non-equilibrium for operating conditions characterized by pressures below 30 000 Pa, frequency 0.37 MHz, input power 80 kW, and mass flow 8 g/s.

  12. Magnetic immunoassay coupled with inductively coupled plasma mass spectrometry for simultaneous quantification of alpha-fetoprotein and carcinoembryonic antigen in human serum

    NASA Astrophysics Data System (ADS)

    Zhang, Xing; Chen, Beibei; He, Man; Zhang, Yiwen; Xiao, Guangyang; Hu, Bin

    2015-04-01

    The absolute quantification of glycoproteins in complex biological samples is a challenge and of great significance. Herein, 4-mercaptophenylboronic acid functionalized magnetic beads were prepared to selectively capture glycoproteins, while antibody conjugated gold and silver nanoparticles were synthesized as element tags to label two different glycoproteins. Based on that, a new approach of magnetic immunoassay-inductively coupled plasma mass spectrometry (ICP-MS) was established for simultaneous quantitative analysis of glycoproteins. Taking biomarkers of alpha-fetoprotein (AFP) and carcinoembryonic antigen (CEA) as two model glycoproteins, experimental parameters involved in the immunoassay procedure were carefully optimized and analytical performance of the proposed method was evaluated. The limits of detection (LODs) for AFP and CEA were 0.086 μg L- 1 and 0.054 μg L- 1 with the relative standard deviations (RSDs, n = 7, c = 5 μg L- 1) of 6.5% and 6.2% for AFP and CEA, respectively. Linear range for both AFP and CEA was 0.2-50 μg L- 1. To validate the applicability of the proposed method, human serum samples were analyzed, and the obtained results were in good agreement with that obtained by the clinical chemiluminescence immunoassay. The developed method exhibited good selectivity and sensitivity for the simultaneous determination of AFP and CEA, and extended the applicability of metal nanoparticle tags based on ICP-MS methodology in multiple glycoprotein quantifications.

  13. Evaluation of a 512-Channel Faraday-Strip Array Detector Coupled to an Inductively Coupled Plasma Mattauch-Herzog Mass Spectrograph

    SciTech Connect

    Schilling, G. D.; Ray, Steven J.; Rubinshtein, Arnon A.; Felton, Jermey; Sperline, Roger P.; Denton, Bonner M.; Barinaga, Charles J.; Koppenaal, David W.; Hieftje, Gary M.

    2009-07-01

    A 512-channel Faraday-strip array detector has been developed and fitted to a Mattauch-Herzog geometry mass spectrograph for the simultaneous acquisition of multiple mass-to-charge values. Several advantages are realized by using simultaneous detection methods, including higher duty cycles, removal of correlated noise, and multianalyte transient analyses independent of spectral skew. The new 512-channel version offers narrower, more closely spaced pixels, providing improved spectral peak sampling and resolution. In addition, the electronics in the amplification stage of the new detector array incorporate a sample-and-hold feature that enables truly simultaneous interrogation of all 512 channels. While sensitivity and linear dynamic range remain impressive for this Faraday-based detector system, limits of detection and isotope ratio data have suffered slightly from leaky p-n junctions produced during the manufacture of the semiconductor-based amplification and readout stages. This paper describes the new 512-channel detector array, the current dominant noise sources, and the figures of merit for the device as pertaining to inductively coupled plasma ionization.

  14. Scandium analysis in silicon-containing minerals by inductively coupled plasma tandem mass spectrometry

    NASA Astrophysics Data System (ADS)

    Whitty-Léveillé, Laurence; Drouin, Elisabeth; Constantin, Marc; Bazin, Claude; Larivière, Dominic

    2016-04-01

    This article reports on the development of a new method for the accurate and precise determination of the amount of scandium, Sc, in silicon-containing minerals, based on the use of tandem quadrupole inductively coupled plasma mass spectrometry (ICP-MS/MS). The tandem quadrupole instrument enables new mass filtering configurations, which can reduce polyatomic interferences during the determination of Sc in mineral matrices. He and O2 were used and compared as collision and reaction gases for the removal of interferences at m/z 45 and 61. Using helium gas was ineffective to overcome all of the spectral interferences observed at m/z 45 and particularly for Si-based interferences. However, conversion of Sc+ ions into ScO+ ions (after bombardment with O2 in the octopole reaction system coupled with the use of the instrument in MS/MS mass-shift mode) provided interference-free conditions and sufficiently low limits of detection, down to 3 ng L- 1, to accurately detect Sc. The accuracy of the proposed methodology was assessed by analyzing five different reference materials (BX-N, OKA-2, NIM-L, SY-3 and GH).

  15. Laser-ablation sampling for inductively coupled plasma distance-of-flight mass spectrometry

    SciTech Connect

    Gundlach-Graham, Alexander W.; Dennis, Elise; Ray, Steven J.; Enke, Christie G.; Barinaga, Charles J.; Koppenaal, David W.; Hieftje, Gary M.

    2015-01-01

    An inductively coupled plasma distance-of-flight mass spectrometer (ICP-DOFMS) has been coupled with laser-ablation (LA) sample introduction for the elemental analysis of solids. ICP-DOFMS is well suited for the analysis of laser-generated aerosols because it offers both high-speed mass analysis and simultaneous multi-elemental detection. Here, we evaluate the analytical performance of the LA-ICP-DOFMS instrument, equipped with a microchannel plate-based imaging detector, for the measurement of steady-state LA signals, as well as transient signals produced from single LA events. Steady-state detection limits are 1 mg g1, and absolute single-pulse LA detection limits are 200 fg for uranium; the system is shown capable of performing time-resolved single-pulse LA analysis. By leveraging the benefits of simultaneous multi-elemental detection, we also attain a good shot-to-shot reproducibility of 6% relative standard deviation (RSD) and isotope-ratio precision of 0.3% RSD with a 10 s integration time.

  16. Antenna coupled Kinetic Inductance arrays for space and ground based imaging arrays

    NASA Astrophysics Data System (ADS)

    Yates, S. J. C.; Baselmans, J. J. A.; Baryshev, A. M.; Neto, A.; Gerini, G.; Barends, R.; Lankwarden, Y. J. Y.

    2009-12-01

    Very large arrays of Microwave Kinetic Inductance Detectors (MKIDs) have the potential to revolutionize ground and space based astronomy. They can offer in excess of 10000 pixels with large dynamic range and very high sensitivity in combination with very efficient frequency division multiplexing at GHz frequencies. In this paper we present the development for a ~100 pixel MKID demonstration array based upon an single pixel consisting of an integrated MKID-antenna detector, with the antenna placed in the second focus of an elliptical Si lens. The design presented can be scaled to any frequency between 80 GHz and >5 THz because there is no need for superconducting structures that become lossy at frequencies above the gap frequency of the materials used. We present measurements of the optical coupling efficiency, sensitivity and discuss array development. We have obtained a dark sensitivity of 7×10-19W/Hz1/2 using 100 nm thick A1 devices and an optical coupling efficiency of 35% referring to the power of a single polarization optical signal in front of the Si lens of the detector.

  17. Rapid determination of uranium isotopes in urine by inductively coupled plasma-mass spectrometry.

    PubMed

    Shi, Y; Dai, X; Collins, R; Kramer-Tremblay, S

    2011-08-01

    Following a radiological or nuclear emergency involving uranium exposure, rapid analytical methods are needed to analyze the concentration of uranium isotopes in human urine samples for early dose assessment. The inductively coupled plasma mass spectrometry (ICP-MS) technique, with its high sample throughput and high sensitivity, has advantages over alpha spectrometry for uranium urinalysis after minimum sample preparation. In this work, a rapid sample preparation method using an anion exchange chromatographic column was developed to separate uranium from the urine matrix. A high-resolution sector field ICP-MS instrument, coupled with a high sensitivity desolvation sample introduction inlet, was used to determine uranium isotopes in the samples. The method can analyze up to 24 urine samples in two hours with the limits of detection of 0.0014, 0.10, and 2.0 pg mL(-1) for (234)U, (235)U, and (238)U, respectively, which meet the requirement for isotopic analysis of uranium in a radiation emergency. PMID:21709502

  18. Separation Of Uranium And Plutonium Isotopes For Measurement By Multi Collector Inductively Coupled Plasma Mass Spectroscopy

    SciTech Connect

    Martinelli, R E; Hamilton, T F; Williams, R W; Kehl, S R

    2009-03-29

    Uranium (U) and plutonium (Pu) isotopes in coral soils, contaminated by nuclear weapons testing in the northern Marshall Islands, were isolated by ion-exchange chromatography and analyzed by mass spectrometry. The soil samples were spiked with {sup 233}U and {sup 242}Pu tracers, dissolved in minerals acids, and U and Pu isotopes isolated and purified on commercially available ion-exchange columns. The ion-exchange technique employed a TEVA{reg_sign} column coupled to a UTEVA{reg_sign} column. U and Pu isotope fractions were then further isolated using separate elution schemes, and the purified fractions containing U and Pu isotopes analyzed sequentially using multi-collector inductively coupled plasma mass spectrometer (MCICP-MS). High precision measurements of {sup 234}U/{sup 235}U, {sup 238}U/{sup 235}U, {sup 236}U/{sup 235}U, and {sup 240}Pu/{sup 239}Pu in soil samples were attained using the described methodology and instrumentation, and provide a basis for conducting more detailed assessments of the behavior and transfer of uranium and plutonium in the environment.

  19. Determination of selenium urinary metabolites by high temperature liquid chromatography-inductively coupled plasma mass spectrometry.

    PubMed

    Terol, A; Ardini, F; Basso, A; Grotti, M

    2015-02-01

    The coupling of high temperature liquid chromatography (HTLC) and inductively coupled plasma mass spectrometry (ICPMS) for the determination of selenium metabolites in urine samples is reported for the first time. In order to achieve "ICPMS-friendly" chromatographic conditions, the retention on a graphite stationary phase of the major selenium urinary metabolites using only plain water with 2% methanol as the mobile phase was investigated. Under the optimal conditions (T=80°C, Ql=1.2 mL min(-1)), methyl 2-acetamido-2-deoxy-1-seleno-β-d-galactopyranoside (selenosugar 1), methyl 2-acetamido-2-deoxy-1-seleno-β-d-glucosopyranoside (selenosugar 2) and trimethylselenonium ion were efficiently separated in less than 7 min, without any interferences due to other common selenium species (selenite, selenate, selenocystine and selenomethionine) or detectable effect of the urine matrix. The limits of detection were 0.3-0.5 ng Se mL(-1), and the precision of the analytical procedure was better than 3% (RSD%, n=5). The HTLC-ICPMS method was applied to the analysis of urine samples from two volunteers before and after ingestion of Brazil nuts or selenium supplements. The developed procedure proved to be adequate for the analytical task, providing results consistent with previous studies. PMID:25582485

  20. Numerical Investigation of Flow Fields in Inductively Coupled Plasma Wind Tunnels

    NASA Astrophysics Data System (ADS)

    Yu, Minghao; Yusuke, Takahashi; Hisashi, Kihara; Ken-ichi, Abe; Kazuhiko, Yamada; Takashi, Abe

    2014-10-01

    Numerical simulations of 10 kW and 110 kW inductively coupled plasma (ICP) wind tunnels were carried out to study physical properties of the flow inside the ICP torch and vacuum chamber with air as the working gas. Two-dimensional compressible axisymmetric Navier-Stokes (N-S) equations that took into account 11 species and 49 chemical reactions of air, were solved. A heat source model was used to describe the heating phenomenon instead of solving the electromagnetic equations. In the vacuum chamber, a four-temperature model was coupled with N-S equations. Numerical results for the 10 kW ICP wind tunnel are presented and discussed in detail as a representative case. It was found that the plasma flow in the vacuum chamber tended to be in local thermochemical equilibrium. To study the influence of operation conditions on the flow field, simulations were carried out for different chamber pressures and/or input powers. The computational results for the above two ICP wind tunnels were compared with corresponding experimental data. The computational and experimental results agree well, therefore the flow fields of ICP wind tunnels can be clearly understood.

  1. Sulfur analysis by inductively coupled plasma-mass spectrometry: A review

    NASA Astrophysics Data System (ADS)

    Giner Martínez-Sierra, J.; Galilea San Blas, O.; Marchante Gayón, J. M.; García Alonso, J. I.

    2015-06-01

    In recent years the number of applications of sulfur (S) analysis using inductively coupled plasma mass spectrometry (ICP-MS) as detector has increased significantly. In this article we describe in some depth the application of ICP-MS for S analysis with emphasis placed on the sulfur-specific detection by hyphenated techniques such as LC, GC, CE and LA coupled on-line to ICP-MS. The different approaches available for sulfur isotope ratio measurements by ICP-MS are also detailed. Particular attention has been paid to the quantification of peptides/proteins and the analysis of metallopeptides/metalloproteins via sulfur by LC-ICP-MS. Likewise, the speciation analysis of metal-based pharmaceuticals and metallodrugs and non-metal selective detection of pharmaceuticals via S are highlighted. Labeling procedures for metabolic applications are also included. Finally, the measurement of natural variations in S isotope composition with multicollector ICP-MS instruments is also covered in this review.

  2. Induction of RAGE Shedding by Activation of G Protein-Coupled Receptors

    PubMed Central

    Metz, Verena V.; Kojro, Elzbieta; Rat, Dorothea; Postina, Rolf

    2012-01-01

    The multiligand Receptor for Advanced Glycation End products (RAGE) is involved in various pathophysiological processes, including diabetic inflammatory conditions and Alzheimes disease. Full-length RAGE, a cell surface-located type I membrane protein, can proteolytically be converted by metalloproteinases ADAM10 and MMP9 into a soluble RAGE form. Moreover, administration of recombinant soluble RAGE suppresses activation of cell surface-located RAGE by trapping RAGE ligands. Therefore stimulation of RAGE shedding might have a therapeutic value regarding inflammatory diseases. We aimed to investigate whether RAGE shedding is inducible via ligand-induced activation of G protein-coupled receptors (GPCRs). We chose three different GPCRs coupled to distinct signaling cascades: the V2 vasopressin receptor (V2R) activating adenylyl cyclase, the oxytocin receptor (OTR) linked to phospholipase Cβ, and the PACAP receptor (subtype PAC1) coupled to adenylyl cyclase, phospholipase Cβ, calcium signaling and MAP kinases. We generated HEK cell lines stably coexpressing an individual GPCR and full-length RAGE and then investigated GPCR ligand-induced activation of RAGE shedding. We found metalloproteinase-mediated RAGE shedding on the cell surface to be inducible via ligand-specific activation of all analyzed GPCRs. By using specific inhibitors we have identified Ca2+ signaling, PKCα/PKCβI, CaMKII, PI3 kinases and MAP kinases to be involved in PAC1 receptor-induced RAGE shedding. We detected an induction of calcium signaling in all our cell lines coexpressing RAGE and different GPCRs after agonist treatment. However, we did not disclose a contribution of adenylyl cyclase in RAGE shedding induction. Furthermore, by using a selective metalloproteinase inhibitor and siRNA-mediated knock-down approaches, we show that ADAM10 and/or MMP9 are playing important roles in constitutive and PACAP-induced RAGE shedding. We also found that treatment of mice with PACAP increases the amount of

  3. Inductively Coupled Plasma and Electron Cyclotron Resonance Plasma Etching of InGaAlP Compound Semiconductor System

    SciTech Connect

    Abernathy, C.R.; Hobson, W.S.; Hong, J.; Lambers, E.S.; Pearton, S.J.; Shul, R.J.

    1998-11-04

    Current and future generations of sophisticated compound semiconductor devices require the ability for submicron scale patterning. The situation is being complicated since some of the new devices are based on a wider diversity of materials to be etched. Conventional IUE (Reactive Ion Etching) has been prevalent across the industry so far, but has limitations for materials with high bond strengths or multiple elements. IrI this paper, we suggest high density plasmas such as ECR (Electron Cyclotron Resonance) and ICP (Inductively Coupled Plasma), for the etching of ternary compound semiconductors (InGaP, AIInP, AlGaP) which are employed for electronic devices like heterojunction bipolar transistors (HBTs) or high electron mobility transistors (HEMTs), and photonic devices such as light-emitting diodes (LEDs) and lasers. High density plasma sources, opeiating at lower pressure, are expected to meet target goals determined in terms of etch rate, surface morphology, surface stoichiometry, selectivity, etc. The etching mechanisms, which are described in this paper, can also be applied to other III-V (GaAs-based, InP-based) as well as III-Nitride since the InGaAIP system shares many of the same properties.

  4. Plasma Characteristics of Large Area Inductively Coupled Plasma System Using Ferrite-Module-Enhanced U-Type Antenna

    NASA Astrophysics Data System (ADS)

    Kim, Kyong Nam; Hyeuk Lim, Jong; Yeom, Geun Young

    2009-11-01

    A ferrite-module-enhanced internal-type linear inductively coupled plasma (ICP) source having multiple U-type antennas operated at 2 MHz has been proposed as a promising candidate to serve as an efficient high-density plasma source for plasma processing areas larger than 2,000×2,300 mm2. When the ICP source was operated at 2 MHz RF power with the ferrite module, high density plasmas on the order of 2.9×1011 cm-3 were obtained at 10 mTorr Ar by applying 4 kW RF power/one U-type antenna; this is 1.5 times higher than the densities obtained at 13.56 MHz without the ferrite module. The higher plasma density obtained with the ICP source operated at 2 MHz with the ferrite module compared with that operated at 13.56 MHz without the ferrite module is related to the magnetic field enhancement caused by the ferrite module. The etch uniformity on a substrate of 2,300×2,000 mm2 at 15 mTorr Ar/O2 (7:3) and about 2.3 kW/U-type antenna was about 11%.

  5. Multiple Functions of Let-23, a Caenorhabditis Elegans Receptor Tyrosine Kinase Gene Required for Vulval Induction

    PubMed Central

    Aroian, R. V.; Sternberg, P. W.

    1991-01-01

    The let-23 gene, which encodes a putative tyrosine kinase of the epidermal growth factor (EGF) receptor subfamily, has multiple functions during Caenorhabditis elegans development. We show that let-23 function is required for vulval precursor cells (VPCs) to respond to the signal that induces vulval differentiation: a complete loss of let-23 function results in no induction. However, some let-23 mutations that genetically reduce but do not eliminate let-23 function result in VPCs apparently hypersensitive to inductive signal: as many as five of six VPCs can adopt vulval fates, in contrast to the three that normally do. These results suggest that the let-23 receptor tyrosine kinase controls two opposing pathways, one that stimulates vulval differentiation and another that negatively regulates vulval differentiation. Furthermore, analysis of 16 new let-23 mutations indicates that the let-23 kinase functions in at least five tissues. Since various let-23 mutant phenotypes can be obtained independently, the let-23 gene is likely to have tissue-specific functions. PMID:2071015

  6. Performance of MBE-4: An experimental multiple beam induction linear accelerator for heavy ions

    SciTech Connect

    Warwick, A.I.; Fessenden, T.J.; Keefe, D.; Kim, C.H.; Meuth, H.

    1988-06-01

    An experimental induction linac, called MBE-4, has been constructed to demonstrate acceleration and current amplification of multiple heavy ion beams. This work is part of a program to study the use of such an accelerator as a driver for heavy ion inertial fusion. MBE-4 is 16m long and accelerates four space-charge-dominated beams of singly-charged cesium ions, in this case from 200 keV to 700 keV, amplifying the current in each beam from 10mA by a factor of nine. Construction of the experiment was completed late in 1987 and we present the results of detailed measurements of the longitudinal beam dynamics. Of particular interest is the contribution of acceleration errors to the growth of current fluctuations and to the longitudinal emittance. The effectiveness of the longitudinal focusing, accomplished by means of the controlled time dependence of the accelerating fields, is also discussed. 4 refs., 5 figs., 1 tab.

  7. A 350 MHz, 200 kW CW, Multiple Beam Inductive Output Tube - Final Report

    SciTech Connect

    R.Lawrece Ives; George Collins; David Marsden Michael Read; Edward Eisen; Takuchi Kamura, Philipp Borchard

    2012-11-28

    This program developed a 200 kW CW, 350 MHz, multiple beam inductive output tube (MBIOT) for driving accelerator cavities. The MBIOT operates at 30 kV with a gain of 23 dB. The estimated efficiency is 70%. The device uses seven electron beams, each transmitting 1.4 A of current. The tube is approximately six feet long and weighs approximately 400 lbs. The prototype device will be evaluated as a potential RF source for the Advanced Photon Source at Argonne National Laboratory (ANL). Because of issues related to delivery of the electron guns, it was not possible to complete assembly and test of the MBIOT during the Phase II program. The device is being completed with support from Calabazas Creek Research, Inc., Communications & Power Industries, LLC. and the Naval Surface Weapons Center (NSWC) in Dahlgren, VA. The MBIOT will be initially tested at NSWC before delivery to ANL. The testing at NSWC is scheduled for February 2013.

  8. 3-Dimensional Modeling of Capacitively and Inductively Coupled Plasma Etching Systems

    NASA Astrophysics Data System (ADS)

    Rauf, Shahid

    2008-10-01

    Low temperature plasmas are widely used for thin film etching during micro and nano-electronic device fabrication. Fluid and hybrid plasma models were developed 15-20 years ago to understand the fundamentals of these plasmas and plasma etching. These models have significantly evolved since then, and are now a major tool used for new plasma hardware design and problem resolution. Plasma etching is a complex physical phenomenon, where inter-coupled plasma, electromagnetic, fluid dynamics, and thermal effects all have a major influence. The next frontier in the evolution of fluid-based plasma models is where these models are able to self-consistently treat the inter-coupling of plasma physics with fluid dynamics, electromagnetics, heat transfer and magnetostatics. We describe one such model in this paper and illustrate its use in solving engineering problems of interest for next generation plasma etcher design. Our 3-dimensional plasma model includes the full set of Maxwell equations, transport equations for all charged and neutral species in the plasma, the Navier-Stokes equation for fluid flow, and Kirchhoff's equations for the lumped external circuit. This model also includes Monte Carlo based kinetic models for secondary electrons and stochastic heating, and can take account of plasma chemistry. This modeling formalism allows us to self-consistently treat the dynamics in commercial inductively and capacitively coupled plasma etching reactors with realistic plasma chemistries, magnetic fields, and reactor geometries. We are also able to investigate the influence of the distributed electromagnetic circuit at very high frequencies (VHF) on the plasma dynamics. The model is used to assess the impact of azimuthal asymmetries in plasma reactor design (e.g., off-center pump, 3D magnetic field, slit valve, flow restrictor) on plasma characteristics at frequencies from 2 -- 180 MHz. With Jason Kenney, Ankur Agarwal, Ajit Balakrishna, Kallol Bera, and Ken Collins.

  9. Comparative Sulfur Analysis Using Thermal Combustion or Inductively Coupled Plasma Methodology and Mineral Composition of Common Livestock Feedstuffs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of this study was to compare the ability of thermal combustion (CNS) and inductively coupled plasma (ICP) to measure the total sulfur (S) content in plant-, animal-, and mineral-based feedstuffs commonly fed to livestock. Analyses of a wide range of feedstuffs by CNS and ICP for total ...

  10. HIGH RESOLUTION INDUCTIVELY COUPLED PLASMA MASS SPECTROMETRY ALLOWS RAPID ASSESSMENT OF IRON ABSORPTION IN INFANTS AND CHILDREN

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Stable isotope absorption studies of iron have been limited by the high cost and limited availability of isotope ratio analysis using thermal ionization MS (TIMS). The development of high-resolution double focusing inductively coupled plasma MS (ICP-MS) may permit more cost-efficient sample analysis...

  11. AC electrokinetic drug delivery in dentistry using an interdigitated electrode assembly powered by inductive coupling.

    PubMed

    Ivanoff, Chris S; Wu, Jie Jayne; Mirzajani, Hadi; Cheng, Cheng; Yuan, Quan; Kevorkyan, Stepan; Gaydarova, Radostina; Tomlekova, Desislava

    2016-10-01

    AC electrokinetics (ACEK) has been shown to deliver certain drugs into human teeth more effectively than diffusion. However, using electrical wires to power intraoral ACEK devices poses risks to patients. The study demonstrates a novel interdigitated electrode arrays (IDE) assembly powered by inductive coupling to induce ACEK effects at appropriate frequencies to motivate drugs wirelessly. A signal generator produces the modulating signal, which multiplies with the carrier signal to produce the amplitude modulated (AM) signal. The AM signal goes through the inductive link to appear on the secondary coil, then rectified and filtered to dispose of its carrier signal, and the positive half of the modulating signal appears on the load. After characterizing the device, the device is validated under light microscopy by motivating carboxylate-modified microspheres, tetracycline, acetaminophen, benzocaine, lidocaine and carbamide peroxide particles with induced ACEK effects. The assembly is finally tested in a common dental bleaching application. After applying 35 % carbamide peroxide to human teeth topically or with the IDE at 1200 Hz, 5 Vpp for 20 min, spectrophotometric analysis showed that compared to diffusion, the IDE enhanced whitening in specular optic and specular optic excluded modes by 215 % and 194 % respectively. Carbamide peroxide absorbance by the ACEK group was two times greater than diffusion as measured by colorimetric oxidation-reduction and UV-Vis spectroscopy at 550 nm. The device motivates drugs of variable molecular weight and structure wirelessly. Wireless transport of drugs to intraoral targets under ACEK effects may potentially improve the efficacy and safety of drug delivery in dentistry. PMID:27565821

  12. Evaluation of number concentration quantification by single-particle inductively coupled plasma mass spectrometry: microsecond vs. millisecond dwell times.

    PubMed

    Abad-Álvaro, Isabel; Peña-Vázquez, Elena; Bolea, Eduardo; Bermejo-Barrera, Pilar; Castillo, Juan R; Laborda, Francisco

    2016-07-01

    The quality of the quantitative information in single-particle inductively coupled plasma mass spectrometry (SP-ICP-MS) depends directly on the number concentration of the nanoparticles in the sample analyzed, which is proportional to the flux of nanoparticles through the plasma. Particle number concentrations must be selected in accordance with the data acquisition frequency, to control the precision from counting statistics and the bias, which is produced by the occurrence of multiple-particle events recorded as single-particle events. With quadrupole mass spectrometers, the frequency of data acquisition is directly controlled by the dwell time. The effect of dwell times from milli- to microseconds (10 ms, 5 ms, 100 μs, and 50 μs) on the quality of the quantitative data has been studied. Working with dwell times in the millisecond range, precision figures about 5 % were achieved, whereas using microsecond dwell times, the suitable fluxes of nanoparticles are higher and precision was reduced down to 1 %; this was independent of the dwell time selected. Moreover, due to the lower occurrence of multiple-nanoparticle events, linear ranges are wider when dwell times equal to or shorter than 100 μs are used. A calculation tool is provided to determine the optimal concentration for any instrument or experimental conditions selected. On the other hand, the use of dwell times in the microsecond range reduces significantly the contribution of the background and/or the presence of dissolved species, in comparison with the use of millisecond dwell times. Although the use of dwell times equal to or shorter than 100 μs offers improved performance working in single-particle mode, the use of conventional dwell times (3-10 ms) should not be discarded, once their limitations are known. PMID:27086011

  13. Computational hydrodynamics and optical performance of inductively-coupled plasma adaptive lenses

    NASA Astrophysics Data System (ADS)

    Mortazavi, M.; Urzay, J.; Mani, A.

    2015-06-01

    This study addresses the optical performance of a plasma adaptive lens for aero-optical applications by using both axisymmetric and three-dimensional numerical simulations. Plasma adaptive lenses are based on the effects of free electrons on the phase velocity of incident light, which, in theory, can be used as a phase-conjugation mechanism. A closed cylindrical chamber filled with Argon plasma is used as a model lens into which a beam of light is launched. The plasma is sustained by applying a radio-frequency electric current through a coil that envelops the chamber. Four different operating conditions, ranging from low to high powers and induction frequencies, are employed in the simulations. The numerical simulations reveal complex hydrodynamic phenomena related to buoyant and electromagnetic laminar transport, which generate, respectively, large recirculating cells and wall-normal compression stresses in the form of local stagnation-point flows. In the axisymmetric simulations, the plasma motion is coupled with near-wall axial striations in the electron-density field, some of which propagate in the form of low-frequency traveling disturbances adjacent to vortical quadrupoles that are reminiscent of Taylor-Görtler flow structures in centrifugally unstable flows. Although the refractive-index fields obtained from axisymmetric simulations lead to smooth beam wavefronts, they are found to be unstable to azimuthal disturbances in three of the four three-dimensional cases considered. The azimuthal striations are optically detrimental, since they produce high-order angular aberrations that account for most of the beam wavefront error. A fourth case is computed at high input power and high induction frequency, which displays the best optical properties among all the three-dimensional simulations considered. In particular, the increase in induction frequency prevents local thermalization and leads to an axisymmetric distribution of electrons even after introduction of

  14. Computational hydrodynamics and optical performance of inductively-coupled plasma adaptive lenses

    SciTech Connect

    Mortazavi, M.; Urzay, J. Mani, A.

    2015-06-15

    This study addresses the optical performance of a plasma adaptive lens for aero-optical applications by using both axisymmetric and three-dimensional numerical simulations. Plasma adaptive lenses are based on the effects of free electrons on the phase velocity of incident light, which, in theory, can be used as a phase-conjugation mechanism. A closed cylindrical chamber filled with Argon plasma is used as a model lens into which a beam of light is launched. The plasma is sustained by applying a radio-frequency electric current through a coil that envelops the chamber. Four different operating conditions, ranging from low to high powers and induction frequencies, are employed in the simulations. The numerical simulations reveal complex hydrodynamic phenomena related to buoyant and electromagnetic laminar transport, which generate, respectively, large recirculating cells and wall-normal compression stresses in the form of local stagnation-point flows. In the axisymmetric simulations, the plasma motion is coupled with near-wall axial striations in the electron-density field, some of which propagate in the form of low-frequency traveling disturbances adjacent to vortical quadrupoles that are reminiscent of Taylor-Görtler flow structures in centrifugally unstable flows. Although the refractive-index fields obtained from axisymmetric simulations lead to smooth beam wavefronts, they are found to be unstable to azimuthal disturbances in three of the four three-dimensional cases considered. The azimuthal striations are optically detrimental, since they produce high-order angular aberrations that account for most of the beam wavefront error. A fourth case is computed at high input power and high induction frequency, which displays the best optical properties among all the three-dimensional simulations considered. In particular, the increase in induction frequency prevents local thermalization and leads to an axisymmetric distribution of electrons even after introduction of

  15. Determination of 234U/238U, 235U/238U and 236U/238U isotope ratios in urine using sector field inductively coupled plasma mass spectrometry.

    PubMed

    Xiao, Ge; Jones, Robert L; Saunders, David; Caldwell, Kathleen L

    2014-12-01

    Quantification of the isotopic composition of uranium in urine at low levels of concentration is important for assessing both military and civilian populations' exposures to uranium. However, until now there has been no convenient, precise method established for rapid determination of multiple uranium isotope ratios. Here, the authors report a new method to measure (234)U/(238)U, (235)U/(238)U and (236)U/(238)U. It uses solid-phase chelation extraction (via TRU columns) of actinides from the urine matrix, followed by measurement using a magnetic sector field inductively coupled plasma mass spectrometer (SF-ICP-MS-Thermo Element XR) equipped with a high-efficiency nebulizer (Apex PFA microflow) and coupled with a membrane desolvating nebulizer system (Aridus II™). This method provides rapid and reliable results and has been used successfully to analyse Certified Reference Materials. PMID:24563523

  16. Inductively coupled plasma -- Atomic emission spectroscopy glove box assembly system at the West Valley Demonstration Project

    SciTech Connect

    Marlow, J.H.; McCarthy, K.M.; Tamul, N.R.

    1999-12-17

    The inductively coupled plasma/atomic emission spectroscopy [ICP/AES (ICP)] system for elemental analyses in support of vitrification processing was first installed in 1986. The initial instrument was a Jobin Yvon (JY) Model JY-70 ICP that consisted of sequential and simultaneous spectrometers for analysis of nonradioactive samples as radioactive surrogates. The JY-70 ICP continued supporting nonradioactive testing during the Functional and Checkout Testing of Systems (FACTS) using the full-scale melter with ``cold'' (nonradioactive) testing campaigns. As a result, the need for another system was identified to allow for the analysis of radioactive samples. The Mass Spec (Spectrometry) Lab was established for the installation of the modified ICP system for handling radioactive samples. The conceptual setup of another ICP was predicated on the use of a hood to allow ease of accessibility of the torch, nebulizer, and spray chamber, and the minimization of air flow paths. However, reconsideration of the radioactive sample dose rate and contamination levels led to the configuration of the glovebox system with a common transfer interface box for the ICP and the inductively coupled plasma-mass spectrometer (ICP-MS) glovebox assemblies. As a result, a simultaneous Model JY-50P ICP with glovebox was installed in 1990 as a first generation ICP glovebox system. This was one of the first ICP glovebox assemblies connected with an ICP-MS glovebox system. Since the economics of processing high-level radioactive waste (HLW) required the availability of an instrument to operate 24 hours a day throughout the year without any downtime, a second generation ICP glovebox assembly was designed, manufactured, and installed in 1995 using a Model JY-46P ICP. These two ICP glovebox systems continue to support vitrification of the HLW into canisters for storage. The ICP systems have been instrumental in monitoring vitrification batch processing. To date, remote sample preparation and

  17. The potential of inductively coupled plasma-mass spectrometric detection for capillary electrophoretic analysis of pesticides.

    PubMed

    Wuilloud, Rodolfo G; Shah, Monika; Kannamkumarath, Sasi S; Altamirano, Jorgelina C

    2005-04-01

    In this work, the potential of inductively coupled plasma-mass spectrometry (ICP-MS) coupled to capillary electrophoresis (CE) to determine organophosphorus pesticides (OPPs) is demonstrated. Element specific detection of (31)P with ICP-MS is performed for the detection of OPPs. Three common OPPs, including glyphosate, glufosinate, and aminomethylphosphonic acid (AMPA), were analyzed by CE-ICP-MS to demonstrate its applicability for the analysis of OPPs. The advantages of using ICP-MS with respect to other common detectors, such as flame photometric detection (FPD), for CE analysis of OPPs are shown. Additionally, different CE separation conditions were studied to achieve complete baseline separation of the pesticide compounds in short migration times. Two CE buffer systems were evaluated for the separation of OPPs using ICP-MS detection. A buffer solution containing 40 mmol.L(-1) ammonium acetate at pH 9.0 and an applied voltage of +20 kV were finally selected leading to a separation time of 10.0 min. Both migration time and area relative standard deviations (%RSD) were evaluated and their respective values were in the intervals of 1.1-3.3% and 2.7-5.3%. Detection limits obtained with the CE-ICP-MS system were in the range of 0.11-0.19 mg.L(-1) (as compound) yielding an enhancement of 130- to 230-fold with respect to FPD. The proposed methodology was finally applied for the determination of the OPPs mentioned above in natural river water samples. PMID:15765486

  18. Inductively coupled plasma-mass spectrometry: An emerging method for analysis of long-lived radionuclides

    SciTech Connect

    Ross, R.R.; Noyce, J.R.; Lardy, M.M.

    1993-12-31

    Inductively coupled plasma-mass spectrometry (ICP-MS) is a relatively new technique that can analyze for most of the elements in the periodic table at parts per billion (ng/mL) to parts per trillion (pg/mL). Already in use several years for trace analysis of stable isotopes, ICP-MS is becoming a powerful, complementary method to the counting of decay radiations for the analysis of radionuclides. Most radionuclides with half-lives longer than approximately 1x10{sup 3} years can be quantitatively detected on ICP-MS instruments that have an electrothermal vaporization unit for the injection of sample aliquants. Radionuclides with half-lives greater than approximately 1x10{sup 4} years can be measured routinely with greater sensitivity and more quickly by ICP-MS than by radiation counting. Examples from the literature of applying ICP-MS to radionuclides are the bioassay of uranium in urine, measurement of {sup 237}Np in soil and silt, and analysis for {sup 99}Tc in sea water, seaweed, and marine sediment. This paper discusses the instrumentation, advantages and limitations, and present and potential applications of ICP-MS for radionuclide measurements.

  19. Macro-loading Effects in Inductively Coupled Plasma Etched Mercury Cadmium Telluride

    NASA Astrophysics Data System (ADS)

    Apte, Palash; Rybnicek, Kimon; Stoltz, Andrew

    2016-05-01

    This paper reports the effect of macro-loading on mercury cadmium telluride (Hg1-x Cd x Te) and Photoresist (PR) etched in an inductively coupled plasma (ICP). A significant macro-loading effect is observed, which affects the etch rates of both PR and Hg1-x Cd x Te. It is observed that the exposed silicon area has a significant effect on the PR etch rate, but not on the Hg1-x Cd x Te etch rate. It is also observed that the exposed Hg1-x Cd x Te area has a significant effect on the etch rate of the PR, but the exposed PR area does not seem to have an effect on the Hg1-x Cd x Te etch rate. Further, the exposed Hg1-x Cd x Te area is shown to affect the etch rate of the Hg1-x Cd x Te, but there does not seem to be a similar effect for the exposed PR area on the etch rate of the PR. Since the macro-loading affects the selectivity significantly, this effect can cause significant problems in the etching of deep trenches. A few techniques to reduce the effect of macro-loading on the etch rates of the PR and Hg1-x Cd x Te are listed, herein.

  20. External control of electron energy distributions in a dual tandem inductively coupled plasma

    SciTech Connect

    Liu, Lei; Sridhar, Shyam; Zhu, Weiye; Donnelly, Vincent M. Economou, Demetre J.; Logue, Michael D.; Kushner, Mark J.

    2015-08-28

    The control of electron energy probability functions (EEPFs) in low pressure partially ionized plasmas is typically accomplished through the format of the applied power. For example, through the use of pulse power, the EEPF can be modulated to produce shapes not possible under continuous wave excitation. This technique uses internal control. In this paper, we discuss a method for external control of EEPFs by transport of electrons between separately powered inductively coupled plasmas (ICPs). The reactor incorporates dual ICP sources (main and auxiliary) in a tandem geometry whose plasma volumes are separated by a grid. The auxiliary ICP is continuously powered while the main ICP is pulsed. Langmuir probe measurements of the EEPFs during the afterglow of the main ICP suggests that transport of hot electrons from the auxiliary plasma provided what is effectively an external source of energetic electrons. The tail of the EEPF and bulk electron temperature were then elevated in the afterglow of the main ICP by this external source of power. Results from a computer simulation for the evolution of the EEPFs concur with measured trends.

  1. Effect of axial finiteness on electron heating in low-frequency inductively coupled plasmas

    SciTech Connect

    Aman-ur-Rehman; Pu, Y.-K.

    2006-10-15

    Total power absorption inside the plasma (by taking the thermal motion of the electrons into account) has been calculated using different inductively coupled plasma models. The comparison shows that in the low-frequency region the results of the semi-infinite plasma models are different from those of the finite-length plasma models. The semi-infinite plasma models show net reduction of heating in the low-frequency region, due to thermal motion of the electrons from inside the skin region to outside the skin region. The finite-length plasma models on the other hand (due to change in the skin depth owing to the boundary condition of E=0 at z=L, and reflection of electrons from the plasma boundary) show that the decrease in heating due to the motion of the electrons from inside the skin depth to outside the skin depth is recovered by the reflection of the electrons from the plasma boundary. Hence, it is concluded that the results of the semi-infinite plasma models presented by Tyshetskiy et al. [Phys Rev. Lett. 90, 255002 (2003)] can be misleading (in the low-frequency region), since they overlooked the effect of axial finiteness of the plasma.

  2. Inductively coupled plasma mass spectrometry in the analysis of biological samples and pharmaceutical drugs

    NASA Astrophysics Data System (ADS)

    Ossipov, K.; Seregina, I. F.; Bolshov, M. A.

    2016-04-01

    Inductively coupled plasma mass spectrometry (ICP-MS) is widely used in the analysis of biological samples (whole blood, serum, blood plasma, urine, tissues, etc.) and pharmaceutical drugs. The shortcomings of this method related to spectral and non-spectral interferences are manifested in full measure in determination of the target analytes in these complex samples strongly differing in composition. The spectral interferences are caused by similarity of masses of the target component and sample matrix components. Non-spectral interferences are related to the influence of sample matrix components on the physicochemical processes taking place during formation and transportation of liquid sample aerosols into the plasma, on the value and spatial distribution of plasma temperature and on the transmission of the ion beam from the interface to mass spectrometer detector. The review is devoted to analysis of different mechanisms of appearance of non-spectral interferences and to ways for their minimization or elimination. Special attention is paid to the techniques of biological sample preparation, which largely determine the mechanisms of the influence of sample composition on the results of element determination. The ways of lowering non-spectral interferences by instrumental parameter tuning and application of internal standards are considered. The bibliography includes 189 references.

  3. Characterization of electron kinetics regime with electron energy probability functions in inductively coupled hydrogen plasmas

    NASA Astrophysics Data System (ADS)

    Kim, June Young; Cho, Won-Hwi; Dang, Jeong-Jeung; Chung, Kyoung-Jae; Hwang, Y. S.

    2016-02-01

    Electron kinetics regime is characterized with the evolution of electron energy probability functions (EEPFs) in inductively coupled hydrogen plasmas. Measurements on EEPFs are carried out with a radio-frequency-compensated single Langmuir probe at the center of a planar-type hydrogen plasma driven by 13.56 MHz wave frequency. Measured EEPFs deviate considerably from the Maxwellian distribution only at relatively high pressures (15-40 mTorr), and the effective electron temperature steeply decreases as the gas pressure increases. Such evolution of the EEPF shapes with pressures is discussed in the consideration of the electron energy relaxation length and various characteristic frequencies. It is found that the EEPFs show locally depleted electron energy distribution where the electron-molecule vibrational collision frequency exceeds the electron-electron collision frequency at the local kinetics regime, while the measured EEPF is not dependent on the vibrational collision frequency at the non-local kinetics regime. Variation of the EEPF shape with distance from the heating region at the local kinetics regime is also well explained in the context of the energy relaxation length and electron-molecule collision frequencies. This study indicates that the control of electron energy distribution should be carried out in the consideration of electron kinetic regime depending on the energy relaxation length for various hydrogen plasma sources.

  4. High sensitivity ultra-broad-band absorption spectroscopy of inductively coupled chlorine plasma

    NASA Astrophysics Data System (ADS)

    Marinov, Daniil; Foucher, Mickaël; Campbell, Ewen; Brouard, Mark; Chabert, Pascal; Booth, Jean-Paul

    2016-06-01

    We propose a method to measure the densities of vibrationally excited Cl2(v) molecules in levels up to v  =  3 in pure chlorine inductively coupled plasmas (ICPs). The absorption continuum of Cl2 in the 250–450 nm spectral range is deconvoluted into the individual components originating from the different vibrational levels of the ground state, using a set of ab initio absorption cross sections. It is shown that gas heating at constant pressure is the major depletion mechanism of the Cl2 feedstock in the plasma. In these line-integrated absorption measurements, the absorption by the hot (and therefore rarefied) Cl2 gas in the reactor centre is masked by the cooler (and therefore denser) Cl2 near the walls. These radial gradients in temperature and density make it difficult to assess the degree of vibrational excitation in the centre of the reactor. The observed line-averaged vibrational distributions, when analyzed taking into account the radial temperature gradient, suggest that vibrational and translational degrees of freedom in the plasma are close to local equilibrium. This can be explained by efficient vibrational-translational (VT) relaxation between Cl2 and Cl atoms. Besides the Cl2(v) absorption band, a weak continuum absorption is observed at shorter wavelengths, and is attributed to photodetachment of Cl‑ negative ions. Thus, line-integrated densities of negative ions in chlorine plasmas can be directly measured using broad-band absorption spectroscopy.

  5. Multielemental inductively coupled plasma optical emission spectrometry analysis of nickeliferous minerals.

    PubMed

    Abad-Peña, Elizabet; Larrea-Marín, María Teresa; Villanueva-Tagle, Margarita Edelia; Pomares-Alfonso, Mario Simeón

    2014-06-01

    An inductively coupled plasma optical emission spectrometry method for the quantitative simultaneous determination of Al, Ca, Co, Cu, Cr, Fe, K, Mg, Mn, Na, Ni, P and Zn in Cuban laterite and serpentine minerals has been developed. Additionally, V and Ti can be quantitatively determined in laterite mineral; Li, Sr, and Zr can be detected in both mineral types and Pb can be detected just in laterite mineral. The microwave-assisted total acid digestion of samples was achieved with HCl+HNO3+HF and HNO3+HClO4+HF acid mixtures for laterite and serpentine samples, respectively. In non-robust plasma operating conditions, the matrix effect characteristics of the laterite sample were dictated by the principal component Fe; while the character of the Mg principal component matrix effect was some how modified by the concomitants Fe and Ni in serpentine sample. The selection of robust conditions decreased the matrix effect. Additionally, the simulation of the matrix samples by introducing the principal component Fe or Mg, correspondingly, in calibration dissolutions was needed to overcome completely the matrix effect over the analysis accuracy. Precision of analysis was very near or lower than 10% for most elements, except Sr (15%) in L-1; and K (15%) and Li (15%) in SNi sample. Accuracy of analysis was around or lowers than 10% for most elements, except K (15%), Na (19%), P (19%) and V (19%) in L-1 sample; and Ca (14%) and P (20%) in SNi sample. PMID:24767449

  6. Surface roughening of ground fused silica processed by atmospheric inductively coupled plasma

    NASA Astrophysics Data System (ADS)

    Xin, Qiang; Li, Na; Wang, Jun; Wang, Bo; Li, Guo; Ding, Fei; Jin, Huiliang

    2015-06-01

    Subsurface damage (SSD) is a defect that is inevitably induced during mechanical processes, such as grinding and polishing. This defect dramatically reduces the mechanical strength and the laser damage thresholds of optical elements. Compared with traditional mechanical machining, atmospheric pressure plasma processing (APPP) is a relatively novel technology that induces almost no SSD during the processing of silica-based optical materials. In this paper, a form of APPP, inductively coupled plasma (ICP), is used to process fused silica substrates with fluorocarbon precursor under atmospheric pressure. The surface morphology evolution of ICP-processed substrates was observed and characterized by confocal laser scanning microscope (CLSM), field emission scanning electron microscope (SEM), and atomic force microscopy (AFM). The results show that the roughness evolves with the etching depth, and the roughness evolution is a single-peaked curve. This curve results from the opening and the coalescing of surface cracks and fractures. The coalescence procedure of these microstructures was simulated with two common etched pits on a polished fused silica surface. Understanding the roughness evolution of plasma-processed surface might be helpful in optimizing the optical fabrication chain that contains APPP.

  7. Analytic Couple Modeling Introducing Device Design Factor, Fin Factor, Thermal Diffusivity Factor, and Inductance Factor

    NASA Technical Reports Server (NTRS)

    Mackey, Jon; Sehirlioglu, Alp; Dynys, Fred

    2014-01-01

    A set of convenient thermoelectric device solutions have been derived in order to capture a number of factors which are previously only resolved with numerical techniques. The concise conversion efficiency equations derived from governing equations provide intuitive and straight-forward design guidelines. These guidelines allow for better device design without requiring detailed numerical modeling. The analytical modeling accounts for factors such as i) variable temperature boundary conditions, ii) lateral heat transfer, iii) temperature variable material properties, and iv) transient operation. New dimensionless parameters, similar to the figure of merit, are introduced including the device design factor, fin factor, thermal diffusivity factor, and inductance factor. These new device factors allow for the straight-forward description of phenomenon generally only captured with numerical work otherwise. As an example a device design factor of 0.38, which accounts for thermal resistance of the hot and cold shoes, can be used to calculate a conversion efficiency of 2.28 while the ideal conversion efficiency based on figure of merit alone would be 6.15. Likewise an ideal couple with efficiency of 6.15 will be reduced to 5.33 when lateral heat is accounted for with a fin factor of 1.0.

  8. Extraction and neutralization of positive and negative ions from a pulsed electronegative inductively coupled plasma

    NASA Astrophysics Data System (ADS)

    Marinov, D.; el Otell, Z.; Bowden, M. D.; Braithwaite, N. St. J.

    2015-12-01

    Almost electron-free (ion-ion) plasmas can be transiently formed during the afterglow phase of pulsed plasmas in electronegative gases. In ion-ion plasmas, both positive and negative ions can be extracted which makes them advantageous for a number of applications. In this paper, we investigate the extraction and acceleration of positive and negative ion beams from a pulsed inductively coupled plasma in SF6. The plasma is bounded by two electrodes biased synchronously with the discharge modulation. It is shown that when a DC bias voltage is applied during the afterglow phase, positive/negative ions are accelerated in a positive/negative space charge sheath formed in front of one of the electrodes. The energy of extracted ions closely follows the amplitude of the applied bias voltage (25-150 V) and the peak beam current density reaches 2 A m-2. With a view to using the described system as a source of energetic neutral beams for low damage material processing, simultaneous extraction and surface neutralization of positive and negative ions using an extraction electrode with high aspect ratio apertures is investigated.

  9. Wireless thin film transistor based on micro magnetic induction coupling antenna

    NASA Astrophysics Data System (ADS)

    Jun, Byoung Ok; Lee, Gwang Jun; Kang, Jong Gu; Kim, Seunguk; Choi, Ji-Woong; Cha, Seung Nam; Sohn, Jung Inn; Jang, Jae Eun

    2015-12-01

    A wireless thin film transistor (TFT) structure in which a source/drain or a gate is connected directly to a micro antenna to receive or transmit signals or power can be an important building block, acting as an electrical switch, a rectifier or an amplifier, for various electronics as well as microelectronics, since it allows simple connection with other devices, unlike conventional wire connections. An amorphous indium gallium zinc oxide (α-IGZO) TFT with magnetic antenna structure was fabricated and studied for this purpose. To enhance the induction coupling efficiency while maintaining the same small antenna size, a magnetic core structure consisting of Ni and nanowires was formed under the antenna. With the micro-antenna connected to a source/drain or a gate of the TFT, working electrical signals were well controlled. The results demonstrated the device as an alternative solution to existing wire connections which cause a number of problems in various fields such as flexible/wearable devices, body implanted devices, micro/nano robots, and sensors for the ‘internet of things’ (IoT).

  10. Wireless thin film transistor based on micro magnetic induction coupling antenna

    PubMed Central

    Jun, Byoung Ok; Lee, Gwang Jun; Kang, Jong Gu; Kim, Seunguk; Choi, Ji-Woong; Cha, Seung Nam; Sohn, Jung Inn; Jang, Jae Eun

    2015-01-01

    A wireless thin film transistor (TFT) structure in which a source/drain or a gate is connected directly to a micro antenna to receive or transmit signals or power can be an important building block, acting as an electrical switch, a rectifier or an amplifier, for various electronics as well as microelectronics, since it allows simple connection with other devices, unlike conventional wire connections. An amorphous indium gallium zinc oxide (α-IGZO) TFT with magnetic antenna structure was fabricated and studied for this purpose. To enhance the induction coupling efficiency while maintaining the same small antenna size, a magnetic core structure consisting of Ni and nanowires was formed under the antenna. With the micro-antenna connected to a source/drain or a gate of the TFT, working electrical signals were well controlled. The results demonstrated the device as an alternative solution to existing wire connections which cause a number of problems in various fields such as flexible/wearable devices, body implanted devices, micro/nano robots, and sensors for the ‘internet of things’ (IoT). PMID:26691929

  11. Effect of silane/hydrogen ratio on microcrystalline silicon thin films by remote inductively coupled plasma

    NASA Astrophysics Data System (ADS)

    Guo, Y. N.; Wei, D. Y.; Xiao, S. Q.; Huang, S. Y.; Zhou, H. P.; Xu, S.

    2013-05-01

    Hydrogenated microcrystalline silicon (μc-Si:H) thin films were prepared by remote low frequency inductively coupled plasma (ICP) chemical vapor deposition system, and the effect of silane/hydrogen ratio on the microstructure and electrical properties of μc-Si:H films was systematically investigated. As silane/hydrogen ratio increases, the crystalline volume fraction Fc decreases and the ratio of the intensity of (220) peak to that of (111) peak drops as silane flow rate is increased. The FTIR result indicates that the μc-Si:H films prepared by remote ICP have a high optical response with a low hydrogen content, which is in favor of reducing light-induced degradation effect. Furthermore, the processing window of the phase transition region for remote ICP is much wider than that for typical ICP. The photosensitivity of μc-Si:H films can exceed 100 at the transition region and this ensures the possibility of the fabrication of microcrystalline silicon thin film solar cells with a open-circuit voltage of about 700 mV.

  12. Low temperature SiNx:H films deposited by inductively coupled plasma for solar cell applications

    NASA Astrophysics Data System (ADS)

    Zhou, H. P.; Wei, D. Y.; Xu, L. X.; Guo, Y. N.; Xiao, S. Q.; Huang, S. Y.; Xu, S.

    2013-01-01

    Amorphous hydrogenated silicon nitride thin films with different chemical compositions (SiNx:H) have been synthesized by using low frequency inductively coupled plasma of Si + N2 + H2 at a low temperature of 100 °C. The bonding configurations, bond density, hydrogen content, and chemical composition, as well as the refractive index are intensively investigated by a variety of characterization tools. Silicon nitride based antireflection layer on alkaline-textured silicon surface reduces the reflectivity to about 4%. As-deposited silicon nitride films exhibit an excellent passivation effect on p- and n-type Si. The surface recombination velocity is reduced to 36 cm/s on n-type silicon with resistivity of 2-3 Ω cm. The passivation effect originates from the H-related chemical passivation and fixed charge related field passivation. The growth mechanism of SiNx:H from the precursor gas of H2 diluted mixture of silane and nitrogen is also discussed.

  13. Experiment and global model of inductively coupled RF Ar/N2 discharges

    NASA Astrophysics Data System (ADS)

    Kimura, Takashi; Kasugai, Hiroki

    2008-10-01

    Plasmas containing N2 have been attracted as a source of active species such as the active atomic nitrogen and the excited nitrogen molecules in the field of material science. In this study, measurements with a Langmuir probe and optical emission spectroscopy are carried out in inductively coupled RF (13.56 MHz) Ar/N2 discharges in the total pressure range from 20mTorr to 100mTorr, changing the N2 content from 5% to 50%. Plasmas are produced in the cylindrical stainless steel chamber with 160 mm in inner diameter and 40 mm in length, where the power injected into the plasma is 200W. The structure of the measured electron energy probability function (EEPF) can be approximated as a Druyvesteyn-like distribution at any N2 content. The electron density, which is on the order of 10^16 -10^17(m-3), increases with increasing the Ar content, whereas the effective electron temperature slightly decreases. The vibrational and rotational temperatures can be estimated from the optical emission spectroscopy of N2 second positive system. The vibrational temperature is higher than 10000K at any experimental condition, and the rotational temperature monotonically increases from 500K to 1000K with the increase in the Ar content. Moreover, the N2 dissociation rate, which corresponds to the density ratio of N to N2, can be estimated by actinometry. The dissociation rate reaches the maximum when the Ar content is about 85%.

  14. Nickel atom and ion densities in an inductively coupled plasma with an internal coil

    NASA Astrophysics Data System (ADS)

    Xu, Lin; Sadeghi, Nader; Donnelly, Vincent M.; Economou, Demetre J.

    2007-01-01

    The nickel atom density was measured in an inductively coupled argon plasma with an internal Ni coil, as a function of pressure and power, using optical absorption spectroscopy. Nickel atoms were sputtered from the coil and from a separate Ni target under optional target bias. A fraction of the atoms was ionized in the high-density plasma. The gas temperature was determined by analyzing the rovibrational spectra of the second positive system of nitrogen actinometer gas. The electron density was determined by optical emission spectroscopy in combination with a global model. For a pressure of 8-20mTorr and coil power of 40-200W, the Ni atom density ranged from 2.7×109to1.5×1010cm-3, increasing strongly with pressure. The Ni atom density first increased with power but saturated at high power levels. The measured Ni atom density agreed fairly well with the predictions of a global model, in particular, at the higher pressures. The model also predicted that the Ni+ ion density greatly increased at higher powers and pressures. Applying 70W bias on the target electrode increased the Ni atom density by 60%.

  15. Kinetic modeling of E-to-H mode transition in inductively coupled hydrogen plasmas

    NASA Astrophysics Data System (ADS)

    Nishida, K.; Mattei, S.; Mochizuki, S.; Lettry, J.; Hatayama, A.

    2016-06-01

    Radio Frequency (RF) Inductively Coupled Plasmas (ICPs) are widely known for their two discharge modes, i.e., H-mode and E-mode, where the dynamics of the plasmas are completely different from each other. We have performed a kinetic simulation of a hydrogen plasma discharge in order to clarify the discharge mechanism and the E-to-H transition of the RF ICPs. The numerical simulation results, such as the time variations of spatial distribution of electron density and the power dissipated in the plasma, show the characteristic changes of the plasma dynamics due to E-to-H mode transition. Especially, the drastic change during the mode transition has been observed in the time evolution of the electron energy distribution function (EEDF). The EEDF deviates from a Maxwellian distribution before/after the transition and the deviation is more significant in the E-mode phase. These results indicate the importance of kinetic modeling for the physical understanding of E-to-H transition.

  16. Langmuir Probe Measurements of Inductively Coupled Plasmas in CF4/Ar/O2 Mixtures

    NASA Technical Reports Server (NTRS)

    Rao, M. V. V. S.; Meyyappan, M.; Sharma, S. P.

    2000-01-01

    Fluorocarbon gases, such as CF4, and their mixtures are widely used in contemporary low-pressure and high-density plasma processing techniques. In such plasmas Langmuir probe is one of the most commonly employed diagnostic techniques to obtain electron number density (ne), electron temperature (Te), electron energy distribution function (EEDF), mean electron energy (Ee), ion number density (ni), and plasma potential (Vp). In this paper we report probe data for planar inductively coupled plasmas in CF4/O2/Ar mixtures. By varying the relative concentrations in the mixture, radial profiles of ne, ni, Te, Ee, Vp, EEDF were measured in the mid-plane of the plasma at 10 mTorr and 20 mTorr of gas pressures, and 200 W and 300 W of RF powers. Data show that ne and ni decrease with increase of CF4 content and decrease of gas-pressure but they increase with increase of RF-power, whereas Vp increases with decrease of gas-pressure and remains independent of RF-power. However, they all peak at the center of the plasma and decrease towards the edge while Te follows the other way and increases a little with increase of power. The measured EEDFs exhibit Druyvesteyn-like distribution at all pressures and powers. Data are analyzed and will be presented.

  17. Langmuir Probe Measurements of Inductively Coupled Plasma in CF4/AR/O2 Mixtures

    NASA Technical Reports Server (NTRS)

    Rao, M. V. V. S.; Cruden, Brett; Sharma, Surendra; Meyyappan, Meyya

    2001-01-01

    Inductively coupled plasmas of CF4:Ar:O2, which have been of importance to material processing, were studied in the GEC cell at 80:10:10, 60:20:20, and 40:30:30 mixture ratios. Radial distributions of plasma potential (V(sub p)), electron and ion number densities (n(sub e) and n(sub i)), electron temperature (T(sub e)), and electron energy distribution functions (EEDFs) were measured in the mid-plane of plasma across the electrodes in the pressure range of 10-50 mTorr, and RF power of 200 and 300 W. V(sub p), n(sub e) and n(sub i), which peak in the center of the plasma, increase with decrease of pressure. T(sub e) also increases with pressure but peaks toward the electrode edge. Both V(sub p) and T(sub e) remain nearly independent of RF power, whereas n(sub e) and n(sub i) increase with power. In all conditions the EEDFs exhibit non-Maxwellian shape and are more like Druyvesteyn form at higher energies. They exhibit a broad lip in the energy range 0-10 eV suggesting an electron loss mechanism, which could be due to via resonance electron attachment processes producing negative ions in this rich electronegative gas mixture. This behavior is more prominent towards the electrode edge.

  18. Langmuir Probe Measurements of Inductively Coupled Plasmas in CF4/Ar/O2 Mixtures

    NASA Technical Reports Server (NTRS)

    Rao, M. V. V. S.; Cruden, Brett; Sharma, Surendra; Meyyappan, Meyya

    2001-01-01

    Inductively coupled plasmas of CF4:Ar:O2, which have been of importance to material processing, were studied in the GEC cell at 80:10:10, 60:20:20, and 40:30:30 mixture ratios. Radial distributions of plasma potential (V(sub p)), electron and ion number densities (n(sub e) and n(sub i), electron temperature (T(sub e)), and electron energy distribution functions (EEDFs) were measured in the mid-plane of plasma across the electrodes in the pressure range of 10-50 mTorr, and RF (radio frequency) power of 200 and 300 W. V(sub p), n(sub e) and n(sub i), which peak in the center of the plasma, increase with decrease of pressure. T(sub e) also increases with pressure but peaks toward the electrode edge. Both V(sub p) and T(sub e) remain nearly independent of RF power, whereas n(sub e) and n(sub i) increase with power. In all conditions the EEDFs exhibit non-Maxwellian shape and are more like Druyvesteyn form at higher energies. They exhibit a broad dip in the energy range 0-10 eV suggesting an electron loss mechanism, which could be due to via resonance electron attachment processes producing negative ions in this rich electronegative gas mixture. This behavior is more prominent towards the electrode edge.

  19. Sulfur-based absolute quantification of proteins using isotope dilution inductively coupled plasma mass spectrometry

    NASA Astrophysics Data System (ADS)

    Lee, Hyun-Seok; Heun Kim, Sook; Jeong, Ji-Seon; Lee, Yong-Moon; Yim, Yong-Hyeon

    2015-10-01

    An element-based reductive approach provides an effective means of realizing International System of Units (SI) traceability for high-purity biological standards. Here, we develop an absolute protein quantification method using double isotope dilution (ID) inductively coupled plasma mass spectrometry (ICP-MS) combined with microwave-assisted acid digestion for the first time. We validated the method and applied it to certify the candidate protein certified reference material (CRM) of human growth hormone (hGH). The concentration of hGH was determined by analysing the total amount of sulfur in hGH. Next, the size-exclusion chromatography method was used with ICP-MS to characterize and quantify sulfur-containing impurities. By subtracting the contribution of sulfur-containing impurities from the total sulfur content in the hGH CRM, we obtained a SI-traceable certification value. The quantification result obtained with the present method based on sulfur analysis was in excellent agreement with the result determined via a well-established protein quantification method based on amino acid analysis using conventional acid hydrolysis combined with an ID liquid chromatography-tandem mass spectrometry. The element-based protein quantification method developed here can be generally used for SI-traceable absolute quantification of proteins, especially pure-protein standards.

  20. Electromagnetic wave attenuation measurements in a ring-shaped inductively coupled air plasma

    NASA Astrophysics Data System (ADS)

    Wei, Xiaolong; Xu, Haojun; Li, Jianhai; Lin, Min; Su; Chen

    2015-05-01

    An aerocraft with the surface, inlet and radome covered large-area inductive coupled plasma (ICP) can attenuate its radar echo effectively. The shape, thickness, and electron density ( N e ) distribution of ICP are critical to electromagnetic wave attenuation. In the paper, an air all-quartz ICP generator in size of 20 × 20 × 7 cm3 without magnetic confinement is designed. The discharge results show that the ICP is amorphous in E-mode and ring-shaped in H-mode. The structure of ICP stratifies into core region and edge halo in H-mode, and its width and thickness changes from power and pressure. Such phenomena are explained by the distribution of RF magnetic field, the diffusion of negative ions plasma and the variation of skin depth. In addition, the theoretical analysis shows that the N e achieves nearly uniform within the electronegative core and sharply steepens in the edge. The N e of core region is diagnosed by microwave interferometer under varied conditions (pressure in range of 10-50 Pa, power in 300-700 W). Furthermore, the electromagnetic wave attenuation measurements were carried out with the air ICP in the frequencies of 4-5 GHz. The results show that the interspaced ICP is still effective to wave attenuation, and the wave attenuation increases with the power and pressure. The measured attenuation is approximately in accordance with the calculation data of finite-different time-domain simulations.

  1. Quantitative images of metals in plant tissues measured by laser ablation inductively coupled plasma mass spectrometry

    NASA Astrophysics Data System (ADS)

    Becker, J. S.; Dietrich, R. C.; Matusch, A.; Pozebon, D.; Dressler, V. L.

    2008-11-01

    Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) was used for quantitative imaging of toxic and essential elements in thin sections (thickness of 30 or 40 μm) of tobacco plant tissues. Two-dimensional images of Mg, Fe, Mn, Zn, Cu, Cd, Rh, Pt and Pb in leaves, shoots and roots of tobacco were produced. Sections of the plant tissues (fixed onto glass slides) were scanned by a focused beam of a Nd:YAG laser in a laser ablation chamber. The ablated material was transported with argon as carrier gas to the ICP ion source at a quadrupole ICP-MS instrument. Ion intensities of the investigated elements were measured together with 13C +, 33S + and 34S + within the entire plant tissue section. Matrix matching standards (prepared using powder of dried tobacco leaves) were used to constitute calibration curves, whereas the regression coefficient of the attained calibration curves was typically 0.99. The variability of LA-ICP-MS process, sample heterogeneity and water content in the sample were corrected by using 13C + as internal standard. Quantitative imaging of the selected elements revealed their inhomogeneous distribution in leaves, shoots and roots.

  2. Highly sensitive immunoassay based on immunogold-silver amplification and inductively coupled plasma mass spectrometric detection.

    PubMed

    Liu, Rui; Liu, Xing; Tang, Yurong; Wu, Li; Hou, Xiandeng; Lv, Yi

    2011-03-15

    In this work, we demonstrated a highly sensitive inductively coupled plasma mass spectrometric (ICPMS) method for the determination of human carcinoembryonic antigen (CEA), which combined the inherent high sensitivity of elemental mass spectrometric measurement with the signal amplification of catalytic silver deposition on immunogold tags. The silver amplification procedure was easy to handle and required cheap reagents, and the sensitivity was greatly enhanced to 60-fold after a 15 min silver amplification procedure. The experimental conditions, including detection of gold and silver by ICPMS, immunoassay parameters, silver amplification parameters, analytical performance, and clinical serum samples analysis, were investigated. The ICPMS Ag signal intensity depends linearly on the logarithm of the concentration of human CEA over the range of 0.07-1000 ng mL(-1) with a limit of detection (LOD, 3σ) of 0.03 ng mL(-1) (i.e., 0.15 pM). The LOD of the proposed method is around 2 orders of magnitude lower than that by the widely used enzyme-linked immunosorbent assay (ELISA) and 1 order of magnitude lower than that by clinical routine chemiluminescence immunoassay (CLIA) or time-resolved fluoroimmunoassay (TRFIA) and conventional ICPMS immunoassay. The present strategy was applied to the determination of human CEA in clinical human serum samples, and the results were in good agreement with those obtained by chemiluminescence immunoassay. PMID:21348438

  3. Feedback control of plasma electron density and ion energy in an inductively coupled plasma etcher

    SciTech Connect

    Lin Chaung; Leou, K.-C.; Huang, H.-M.; Hsieh, C.-H.

    2009-01-15

    Here the authors report the development of a fuzzy logic based feedback control of the plasma electron density and ion energy for high density plasma etch process. The plasma electron density was measured using their recently developed transmission line microstrip microwave interferometer mounted on the chamber wall, and the rf voltage was measured by a commercial impedance meter connected to the wafer stage. The actuators were two 13.56 MHz rf power generators which provided the inductively coupled plasma power and bias power, respectively. The control system adopted the fuzzy logic control algorithm to reduce frequent actuator action resulting from measurement noise. The experimental results show that the first wafer effect can be eliminated using closed-loop control for both poly-Si and HfO{sub 2} etching. In particular, for the HfO2 etch, the controlled variables in this work were much more effective than the previous one where ion current was controlled, instead of the electron density. However, the pressure disturbance effect cannot be reduced using plasma electron density feedback.

  4. Biofuel cell based on microscale nanostructured electrodes with inductive coupling to rat brain neurons.

    PubMed

    Andoralov, Viktor; Falk, Magnus; Suyatin, Dmitry B; Granmo, Marcus; Sotres, Javier; Ludwig, Roland; Popov, Vladimir O; Schouenborg, Jens; Blum, Zoltan; Shleev, Sergey

    2013-01-01

    Miniature, self-contained biodevices powered by biofuel cells may enable a new generation of implantable, wireless, minimally invasive neural interfaces for neurophysiological in vivo studies and for clinical applications. Here we report on the fabrication of a direct electron transfer based glucose/oxygen enzymatic fuel cell (EFC) from genuinely three-dimensional (3D) nanostructured microscale gold electrodes, modified with suitable biocatalysts. We show that the process underlying the simple fabrication method of 3D nanostructured electrodes is based on an electrochemically driven transformation of physically deposited gold nanoparticles. We experimentally demonstrate that mediator-, cofactor-, and membrane-less EFCs do operate in cerebrospinal fluid and in the brain of a rat, producing amounts of electrical power sufficient to drive a self-contained biodevice, viz. 7 μW cm(-2) in vitro and 2 μW cm(-2) in vivo at an operating voltage of 0.4 V. Last but not least, we also demonstrate an inductive coupling between 3D nanobioelectrodes and living neurons. PMID:24253492

  5. Measuring ion velocity distribution functions through high-aspect ratio holes in inductively coupled plasmas

    NASA Astrophysics Data System (ADS)

    Cunge, G.; Darnon, M.; Dubois, J.; Bezard, P.; Mourey, O.; Petit-Etienne, C.; Vallier, L.; Despiau-Pujo, E.; Sadeghi, N.

    2016-02-01

    Several issues associated with plasma etching of high aspect ratio structures originate from the ions' bombardment of the sidewalls of the feature. The off normal angle incident ions are primarily due to their temperature at the sheath edge and possibly to charging effects. We have measured the ion velocity distribution function (IVDF) at the wafer surface in an industrial inductively coupled plasma reactor by using multigrid retarding field analyzers (RFA) in front of which we place 400 μm thick capillary plates with holes of 25, 50, and 100 μm diameters. The RFA then probes IVDF at the exit of the holes with Aspect Ratios (AR) of 16, 8, and 4, respectively. The results show that the ion flux dramatically drops with the increase in AR. By comparing the measured IVDF with an analytical model, we concluded that the ion temperature is 0.27 eV in our plasma conditions. The charging effects are also observed and are shown to significantly reduce the ion energy at the bottom of the feature but only with a "minor" effect on the ion flux and the shape of the IVDF.

  6. Investigation of palladium and platinum levels in food by sector field inductively coupled plasma mass spectrometry.

    PubMed

    Frazzoli, Chiara; Cammarone, Roberta; Caroli, Sergio

    2007-05-01

    Over the last two decades, there has been increased concern regarding the impact of some noble metals, such as Pd and Pt, on human health. These elements pollute the environment due to their widespread use as catalytic converters and in medical applications. The risk they pose to human health and the environment is still controversial; however, literature data point to diet as an important source of uptake by the human body. Within this context, the total Pd and Pt content of several Italian food commodities has been investigated. A total of 90 samples, including flour products, vegetables and foodstuffs of animal origin (meat, milk and eggs), were collected and freeze-dried. Samples were analyzed by sector field inductively coupled plasma mass spectrometry (SF-ICP-MS) after chopping or crushing followed by freeze-drying and microwave (MW)-assisted acid digestion in a Class-100 clean-room. A mathematical approach was adopted to correct the mass signals for still unresolved interference (mDeltam = 300, 10 000). The lowest and highest concentrations of Pt, i.e. 17 and 93 ng kg(-1) (dry weight, dw), were found in vegetables and flour products, respectively. The lowest Pd level (2830 ng kg(-1) dw) was found in eggs and the highest (47 800 ng kg(-1) dw) in vegetables. PMID:17487666

  7. Plutonium determination in seawater by inductively coupled plasma mass spectrometry: A review.

    PubMed

    Cao, Liguo; Bu, Wenting; Zheng, Jian; Pan, Shaoming; Wang, Zhongtang; Uchida, Shigeo

    2016-05-01

    Knowing the concentration and isotopic ratio of Pu in seawater is of critical importance for assessing Pu contamination and investigating oceanic processes. In recent decades, the concentration of (239+240)Pu in seawater, particularly for surface seawater, has presented an exponential decreasing trend with time; thus determination of Pu in seawater has become a challenge nowadays. Here, we have summarized and critically discussed a variety of reported analytical methods for Pu determination in seawater sample based on inductively coupled plasma mass spectrometry (ICP-MS) analytical technique for rapid ultra-trace detection of Pu. Generally, pretreatments for seawater sample include co-precipitation, valence adjustment and chemical separation and purification procedures, all of which are comprehensively reviewed. Overall, the selected anion-exchange, extraction resins and operation condition are important for decontamination of interference from matrix elements and achieving satisfactory chemical yields. In addition, other mass spectrometric and radiometric detections are briefly addressed and compared with the focus on assessing ICP-MS. Finally, we discuss some issues and prospects in determination and application of Pu isotopes in seawater samples for future research. PMID:26946007

  8. Biofuel Cell Based on Microscale Nanostructured Electrodes with Inductive Coupling to Rat Brain Neurons

    NASA Astrophysics Data System (ADS)

    Andoralov, Viktor; Falk, Magnus; Suyatin, Dmitry B.; Granmo, Marcus; Sotres, Javier; Ludwig, Roland; Popov, Vladimir O.; Schouenborg, Jens; Blum, Zoltan; Shleev, Sergey

    2013-11-01

    Miniature, self-contained biodevices powered by biofuel cells may enable a new generation of implantable, wireless, minimally invasive neural interfaces for neurophysiological in vivo studies and for clinical applications. Here we report on the fabrication of a direct electron transfer based glucose/oxygen enzymatic fuel cell (EFC) from genuinely three-dimensional (3D) nanostructured microscale gold electrodes, modified with suitable biocatalysts. We show that the process underlying the simple fabrication method of 3D nanostructured electrodes is based on an electrochemically driven transformation of physically deposited gold nanoparticles. We experimentally demonstrate that mediator-, cofactor-, and membrane-less EFCs do operate in cerebrospinal fluid and in the brain of a rat, producing amounts of electrical power sufficient to drive a self-contained biodevice, viz. 7 μW cm-2 in vitro and 2 μW cm-2 in vivo at an operating voltage of 0.4 V. Last but not least, we also demonstrate an inductive coupling between 3D nanobioelectrodes and living neurons.

  9. Macro-loading Effects in Inductively Coupled Plasma Etched Mercury Cadmium Telluride

    NASA Astrophysics Data System (ADS)

    Apte, Palash; Rybnicek, Kimon; Stoltz, Andrew

    2016-09-01

    This paper reports the effect of macro-loading on mercury cadmium telluride (Hg1- x Cd x Te) and Photoresist (PR) etched in an inductively coupled plasma (ICP). A significant macro-loading effect is observed, which affects the etch rates of both PR and Hg1- x Cd x Te. It is observed that the exposed silicon area has a significant effect on the PR etch rate, but not on the Hg1- x Cd x Te etch rate. It is also observed that the exposed Hg1- x Cd x Te area has a significant effect on the etch rate of the PR, but the exposed PR area does not seem to have an effect on the Hg1- x Cd x Te etch rate. Further, the exposed Hg1- x Cd x Te area is shown to affect the etch rate of the Hg1- x Cd x Te, but there does not seem to be a similar effect for the exposed PR area on the etch rate of the PR. Since the macro-loading affects the selectivity significantly, this effect can cause significant problems in the etching of deep trenches. A few techniques to reduce the effect of macro-loading on the etch rates of the PR and Hg1- x Cd x Te are listed, herein.

  10. Inductively coupled plasma mass spectrometer with laser ablation metal ions release detection in the human mouth

    NASA Astrophysics Data System (ADS)

    Kueerova, Hana; Dostalova, Tatjana; Prochazkova, J.

    2002-06-01

    Presence of more dental alloys in oral cavity often causes pathological symptoms. Due to various and multi-faced symptomatology, they tend to be a source of significant problems not only for the patient but also for the dentist. Metal ions released from alloys can cause subjective and objective symptoms in mouth. The aim of this study was detection of metal elements presence in saliva. There were 4 groups of examined persons: with intact teeth (15 individuals) with metallic restorations, pathological currents 5-30 (mu) A, multi-faced subjective symptomatology and uncharacteristic objective diagnosis (32 patients), with metallic restorations and no subjective symptoms (14 persons) and with metallic restorations, without pathological currents and with problems related to galvanism (13 patients). Presence of 14 metal elements was checked by inductively coupled plasma mass spectrometer with laser ablation. Nd:YAG laser detector was used. There were significant differences in content of silver, gold and mercury between persons with intact teeth and other three groups. There were no differences found between subjects with and without galvanic currents, and presence of subjective and objective symptoms.

  11. Ion Energy Distributions and their Relative Abundance in Inductively Coupled Plasmas

    NASA Technical Reports Server (NTRS)

    Kim, J. S.; Rao, M. V. V. S.; Cappelli, M. A.; Sharma, S. P.; Arnold, James O. (Technical Monitor)

    1998-01-01

    Study of kinetics of ions and neutrals produced in high density inductively coupled plasma (ICP) discharges is of great importance for achieving a high degree of plasma assisted deposition and etching. In this paper, we present the ion energy distributions (IEDs) of various ions arriving at the grounded lower electrode. The ions were energy as well as mass analyzed by a combination of electrostatic analyzer-quadrupole mass spectrometer for pure Ar and CF4/Ar mixtures. The measurements have been made at gas pressures ranging from 30 to 100 mTorr. In addition, the IEDs were measured when the wafer-supporting electrode was also rf-powered and the effect of the self-bias was observed in the energy distributions of ions. The shapes of the IEDs are discussed an related to the sheath properties and measured electrical waveforms, as a function of pressure and applied power. Relative ion intensities were obtained by integration of each ion kinetic energy distribution function over its energy range.

  12. [Determination of Heavy Metal Elements in Diatomite Filter Aid by Inductively Coupled Plasma Mass Spectrometry].

    PubMed

    Nie, Xi-du; Fu, Liang

    2015-11-01

    This study established a method for determining Be, Cr, Ni, As, Cd, Sb, Sn, Tl, Hg and Pb, total 10 heavy metals in diatomite filter aid. The diatomite filter aid was digested by using the mixture acid of HNO₃ + HF+ H₃PO₄ in microwave system, 10 heavy metals elements were determined by inductively coupled plasma mass spectrometry (ICP-MS). The interferences of mass spectrometry caused by the high silicon substrate were optimized, first the equipment parameters and isotopes of test metals were selected to eliminate these interferences, the methane was selected as reactant gas, and the mass spectral interferences were eliminated by dynamic reaction cell (DRC). Li, Sc, Y, In and Bi were selected as the internal standard elements to correct the interferences caused by matrix and the drift of sensitivity. The results show that the detection limits for analyte is in the range of 3.29-15.68 ng · L⁻¹, relative standard deviations (RSD) is less than 4.62%, and the recovery is in the range of 90.71%-107.22%. The current method has some advantages such as, high sensitivity, accurate, and precision, which can be used in diatomite filter aid quality control and safety estimations. PMID:26978934

  13. Elemental Bioimaging by Means of Fast Scanning Laser Ablation-Inductively Coupled Plasma-Mass Spectrometry

    NASA Astrophysics Data System (ADS)

    Wehe, Christoph A.; Thyssen, Georgina M.; Herdering, Christina; Raj, Indra; Ciarimboli, Giuliano; Sperling, Michael; Karst, Uwe

    2015-08-01

    One of the most common setups for elemental bioimaging, the hyphenation of a laser ablation (LA) system and an inductively coupled plasma mass spectrometer (ICP-MS), was expanded by adding full scan mass spectrometric information as another dimension of information. While most studies deal with the analysis of typically not more than up to 10 isotopes per scan cycle, a fast scanning quadrupole mass analyzer was utilized to record the full mass spectrum of interest in this work. Mass-to-charge ratios from 6 to 250 were observed within one cycle. Besides the x- and y-position on the ablated sample and the intensity, the m/z-ratio served as fourth variable for each pixel of the obtained data, closing thereby the gap between "inorganic" and "organic" mass spectrometric imaging techniques. The benefits of this approach include an improved control of interferences, the discovery of unexpected elemental distributions, the possibility to plot isotopic ratios, and to integrate the intensities of a certain number of mass channels recorded for each isotope, thus virtually increasing sensitivity. The respective data are presented for dried droplets as well as embedded animal and human tissue slices. Limits of detection were calculated and found to be in accordance with counting statistics. A dedicated software macro was developed for data manipulation prior to common evaluation and image creation.

  14. Direct determination of metals in organics by inductively coupled plasma atomic emission spectrometry in aqueous matrices.

    PubMed

    Wang, Tiebang; Jia, Xiujuan; Wu, Jane

    2003-11-24

    A simple method for the simultaneous determination of up to 21 elements in organic matrices is proposed. Organic samples are simply dispersed in concentrated nitric acid by sonication, and the resulting emulsions/suspensions are directly aspirated into an inductively coupled plasma atomic emission spectrometer (ICP-AES) calibrated with aqueous standards for analysis. Proof of concept was provided by the excellent recoveries for the analysis of a 21-element metallo-organic standard. In addition, the results obtained using this method for a waste oil sample compared favorably with those from a method that utilized microwave digestion for sample preparation. Comparable results were also obtained by dilution in an organic solvent followed by ICP-AES analysis with an ultrasonic nebulizer equipped with a membrane desolvator. Furthermore, the viability and validity of this method were confirmed by the analysis of the National Institute of Standards and Technology standard reference material 1084a Wear-Metals in Lubricating Oil. Spike recoveries ranged from 83 to 105% and the limits of quantitation were 6 microg g(-1) or less for all the elements analyzed. PMID:14623589

  15. Oxygen bomb combustion of biological samples for inductively coupled plasma optical emission spectrometry

    NASA Astrophysics Data System (ADS)

    Souza, Gilberto B.; Carrilho, Elma Neide V. M.; Oliveira, Camila V.; Nogueira, Ana Rita A.; Nóbrega, Joaquim A.

    2002-12-01

    A rapid sample preparation method is proposed for decomposition of milk powder, corn bran, bovine and fish tissues, containing certified contents of the analytes. The procedure involves sample combustion in a commercial stainless steel oxygen bomb operating at 25 bar. Most of the samples were decomposed within 5 min. Diluted nitric acid or water-soluble tertiary amines 10% v/v were used as absorption solutions. Calcium, Cu, K, Mg, Na, P, S and Zn were recovered with the bomb washings and determined by inductively coupled plasma optical emission spectrometry (ICP-OES). Ethanol mixed with paraffin was used as a combustion aid to allow complete combustion. A cooling step prior releasing of the bomb valve was employed to increase the efficiency of sample combustion. Iodine was also determined in milk samples spiked with potassium iodide to evaluate the volatilization and collection of iodine in amine CFA-C medium and the feasibility of its determination by ICP-OES with axial view configuration. Most of the element recoveries in the samples were between 91 and 105% and the certified and found contents exhibited a fair agreement at a 95% confidence level.

  16. Controlling VUV photon fluxes in low-pressure inductively coupled plasmas

    NASA Astrophysics Data System (ADS)

    Tian, Peng; Kushner, Mark J.

    2015-06-01

    Low-pressure (a few to hundreds of millitorrs) inductively coupled plasmas (ICPs), as typically used in microelectronics fabrication, often produce vacuum-ultraviolet (VUV) photon fluxes onto surfaces comparable to or exceeding the magnitude of ion fluxes. These VUV photon fluxes are desirable in applications such as sterilization of medical equipment but are unwanted in many materials fabrication processes due to damage to the devices by the high-energy photons. Under specific conditions, VUV fluxes may stimulate etching or synergistically combine with ion fluxes to modify polymeric materials. In this regard, it is desirable to control the magnitude of VUV fluxes or the ratio of VUV fluxes to those of other reactive species, such as ions, or to discretely control the VUV spectrum. In this paper, we discuss results from a computational investigation of VUV fluxes from low-pressure ICPs sustained in rare gas mixtures. The control of VUV fluxes through the use of pressure, pulsed power, and gas mixture is discussed. We found that the ratio, β, of VUV photon to ion fluxes onto surfaces generally increases with increasing pressure. When using pulsed plasmas, the instantaneous value of β can vary by a factor of 4 or more during the pulse cycle due to the VUV flux more closely following the pulsed power.

  17. Inductively coupled plasma mass spectrometry applied to isotopic analysis of iron in human fecal matter

    SciTech Connect

    Ting, B.T.G.; Janghorbani, M.

    1986-06-01

    Inductively coupled plasma mass spectrometry combined with stable isotope dilution is applied to accurate isotopic analysis of human fecal matter for /sup 54/Fe and /sup 58/Fe. Argon plasma generated interferences are of minor concern. The interference from /sup 54/Cr can be corrected instrumentally, whereas /sup 58/Ni must be removed chemically. The ratio of the stable isotopes of interest can be measured routinely with a relative standard deviation of about 1%. The overall accuracy of the method for quantitative isotopic analyses is evaluated in Standard Reference Material (SRM) 1577a (Bovine Liver), fecal homogenate subsamples, and synthetic solutions of iron. For SRM 1577a, the respective comparisons are (..mu..g/g) 192.2 +/- 2.2 (present method) vs. 194 +/- 20 (certified value). For the fecal matrix, the present method yields (..mu..g/mL) 15.14 +/- 0.36 vs. 15.82 +/- 0.48 based on atomic absorption spectrophotometry. For an iron solution (250 ppm), replicate analyses yield the value of 245.4 +/- 1.5 ppm.

  18. Determination of cobalamins using capillary electrophoresis inductively coupled plasma mass spectrometry

    NASA Astrophysics Data System (ADS)

    Baker, S. A.; Miller-Ihli, N. J.

    2000-12-01

    The determination of cobalamins using capillary electrophoresis inductively coupled plasma mass spectrometry (CE-ICP-MS) was investigated. Both capillary zone electrophoresis (CZE) and micellar electrokinetic chromatography (MEKC) modes of operation were studied. The optimal separation of four cobalamin species (cyanocobalamin, hydroxocobalamin, methylcobalamin, and 5'-deoxyadenosylcobalamin) and a potentially harmful corrinoid analogue (cobinamide dicyanide) was obtained using CZE at a pH of 2.5. Both 20 mM phosphate and 20 mM formate buffers were used with success, although the formate buffer provided improved resolution. The CZE-ICP-MS method was used to quantify cyanocobalamin in a vitamin supplement and the analytical results were in good agreement (±5%) with values obtained by ICP-MS for total Co levels. The solution detection limits for cobalamins using CZE-ICP-MS were approximately 50 ng/ml. MEKC was found to be useful for the screening of vitamin preparations because it provided a rapid means of distinguishing cyanocobalamin (the form most commonly used in vitamin preparations) from free cobalt. The separation of free cobalt and cyanocobalamin using MEKC was achieved in less than 10 min.

  19. In situ measurement of tissue impedance using an inductive coupling interface circuit.

    PubMed

    Chiu, Hung-Wei; Chuang, Jia-min; Lu, Chien-Chi; Lin, Wei-Tso; Lin, Chii-Wann; Lin, Mu-Lien

    2013-06-01

    In this work, a method of an inductive coupling impedance measurement (ICIM) is proposed for measuring the nerve impedance of a dorsal root ganglion (DRG) under PRF stimulation. ICIM provides a contactless interface for measuring the reflected impedance by an impedance analyzer with a low excitation voltage of 7 mV. The paper develops a calibration procedure involving a 50-Ω reference resistor to calibrate the reflected resistance for measuring resistance of the nerve in the test. A de-embedding technique to build the equivalent transformer circuit model for the ICIM circuit is also presented. A batteryless PRF stimulator with ICIM circuit demonstrated good accuracy for the acute measurement of DRG impedance both in situ and in vivo. Besides, an in vivo animal experiment was conducted to show that the effectiveness of pulsed radiofrequency (PRF) stimulation in relieving pain gradually declined as the impedance of the stimulated nerve increased. The experiment also revealed that the excitation voltage for measuring impedance below 25 mV can prevent the excitation of a nonlinear response of DRG. PMID:23853322

  20. Langmuir Probe Distortions and Probe Compensation in an Inductively Coupled Plasma

    NASA Technical Reports Server (NTRS)

    Ji, J. S.; Cappelli, M. A.; Kim, J. S.; Rao, M. V. V. S.; Sharma, S. P.

    1999-01-01

    In many RF discharges, Langmuir probe measurements are usually made against a background of sinusoidal (and not so sinusoidal) fluctuations in the plasma parameters such as the plasma potential (Vp), the electron number density (ne), and the electron temperature (Te). The compensation of sinusoidal fluctuations in Vp has been extensively studied and is relatively well understood. Less attention has been paid to the possible distortions introduced by small fluctuations in plasma density and/or plasma temperature, which may arise in the sheath and pre-sheath regions of RF discharges. Here, we present the results of a model simulation of probe characteristics subject to fluctuations in both Vp and ne. The modeling of probe distortion due to possible fluctuations in Te is less straightforward. A comparison is presented of calculations with experimental measurements using a compensated and uncompensated Langmuir probe in an inductively coupled GEC reference cell plasma, operating on Ar and Ar/CF4 mixtures. The plasma parameters determined from the compensated probe characteristics are compared to previous measurements of others made in similar discharges, and to our own measurements of the average electron density derived from electrical impedance measurements.

  1. Spark ablation-inductively coupled plasma spectrometry for analysis of geologic materials

    USGS Publications Warehouse

    Golightly, D.W.; Montaser, A.; Smith, B.L.; Dorrzapf, A.F., Jr.

    1989-01-01

    Spark ablation-inductively coupled plasma (SA-ICP) spectrometry is applied to the measurement of hafnium-zirconium ratios in zircons and to the determination of cerium, cobalt, iron, lead, nickel and phosphorus in ferromanganese nodules. Six operating parameters used for the high-voltage spark and argon-ICP combination are established by sequential simplex optimization of both signal-to-background ratio and signal-to-noise ratio. The time-dependences of the atomic emission signals of analytes and matrix elements ablated from a finely pulverized sample embedded in a pressed disk of copper demonstrate selective sampling by the spark. Concentration ratios of hafnium to zirconium in zircons are measured with a precision of 4% (relative standard deviation, RSD). For ferromanganese nodules, spectral measurements based on intensity ratios of analyte line to the Mn(II) 257.610 nm line provide precisions of analysis in the range from 7 to 14% RSD. The accuracy of analysis depends on use of standard additions of the reference material USGS Nod P-1, and an independent measurement of the Mn concentration. ?? 1989.

  2. Some Temperature Effects on AISI-304 Nitriding in an Inductively Coupled RF Plasma

    SciTech Connect

    Valencia-Alvarado, R.; Barocio, S. R.; Mercado-Cabrera, A.; Pena-Eguiluz, R.; Munoz-Castro, A. E.; Piedad-Beneitez, A. de la; Rosa-Vazquez, J. de la; Lopez-Callejas, R.; Godoy-Cabrera, O. G.

    2006-12-04

    Some recent results obtained from nitriding AISI 304 stainless steel samples, 1.2 cm in diameter and 0.5 cm thick are reported here in the case of an 85% hydrogen and 15% nitrogen mixture work gas. The process was carried out from 300 to 400 W for (13.56 MHz) inductively coupled plasma within a 60 cm long pyrex glass tube 3.5 cm in diameter where the samples were biased up to -300 V with respect to earth. The resulting hardness appears to be a function of the substrate temperature which varied from 200 deg. C at a 0 V bias to 550 deg. C at -300 V. The plasma density at 400 W reached 3x1010 cm-3 with a 4 eV electron temperature. Prior to nitriding, all the samples were polished with 0.05 {mu}m diamond paste, leading to a 30 nm average roughness (Ra). After nitriding at -300 V, the Ra rose until {approx}400 nm while hardness values of 1500 HV under 300 g loads were measured. X ray diffraction indicates that the extended phase amplitude ({gamma}N), Fe and Cr nitride depends on the substrate temperature.

  3. High Resolution Studies of the Origins of Polyatomic Ions in Inductively Coupled Plasma-Mass Spectrometry

    SciTech Connect

    Jill Wisnewski Ferguson

    2006-08-09

    The inductively coupled plasma (ICP) is an atmospheric pressure ionization source. Traditionally, the plasma is sampled via a sampler cone. A supersonic jet develops behind the sampler, and this region is pumped down to a pressure of approximately one Torr. A skimmer cone is located inside this zone of silence to transmit ions into the mass spectrometer. The position of the sampler and skimmer cones relative to the initial radiation and normal analytical zones of the plasma is key to optimizing the useful analytical signal [1]. The ICP both atomizes and ionizes the sample. Polyatomic ions form through ion-molecule interactions either in the ICP or during ion extraction [l]. Common polyatomic ions that inhibit analysis include metal oxides (MO{sup +}), adducts with argon, the gas most commonly used to make up the plasma, and hydride species. While high resolution devices can separate many analytes from common interferences, this is done at great cost in ion transmission efficiency--a loss of 99% when using high versus low resolution on the same instrument [2]. Simple quadrupole devices, which make up the bulk of ICP-MS instruments in existence, do not present this option. Therefore, if the source of polyatomic interferences can be determined and then manipulated, this could potentially improve the figures of merit on all ICP-MS devices, not just the high resolution devices often utilized to study polyatomic interferences.

  4. On anomalous temporal evolution of gas pressure in inductively coupled plasma

    SciTech Connect

    Seo, B. H.; Chang, H. Y.; You, S. J.; Kim, J. H.; Seong, D. J.

    2013-04-01

    The temporal measurement of gas pressure in inductive coupled plasma revealed that there is an interesting anomalous evolution of gas pressure in the early stage of plasma ignition and extinction: a sudden gas pressure change and its relaxation of which time scales are about a few seconds and a few tens of second, respectively, were observed after plasma ignition and extinction. This phenomenon can be understood as a combined result between the neutral heating effect induced by plasma and the pressure relaxation effect for new gas temperature. The temporal measurement of gas temperature by laser Rayleigh scattering and the time dependant calculations for the neutral heating and pressure relaxation are in good agreement with our experimental results. This result and physics behind are expected to provide a new operational perspective of the recent plasma processes of which time is very short, such as a plasma enhanced atomic layer deposition/etching, a soft etch for disposal of residual by-products on wafer, and light oxidation process in semiconductor manufacturing.

  5. Ion Clouds in the Inductively Coupled Plasma Torch: A Closer Look through Computations.

    PubMed

    Aghaei, Maryam; Lindner, Helmut; Bogaerts, Annemie

    2016-08-16

    We have computationally investigated the introduction of copper elemental particles in an inductively coupled plasma torch connected to a sampling cone, including for the first time the ionization of the sample. The sample is inserted as liquid particles, which are followed inside the entire torch, i.e., from the injector inlet up to the ionization and reaching the sampler. The spatial position of the ion clouds inside the torch as well as detailed information on the copper species fluxes at the position of the sampler orifice and the exhausts of the torch are provided. The effect of on- and off-axis injection is studied. We clearly show that the ion clouds of on-axis injected material are located closer to the sampler with less radial diffusion. This guarantees a higher transport efficiency through the sampler cone. Moreover, our model reveals the optimum ranges of applied power and flow rates, which ensure the proper position of ion clouds inside the torch, i.e., close enough to the sampler to increase the fraction that can enter the mass spectrometer and with minimum loss of material toward the exhausts as well as a sufficiently high plasma temperature for efficient ionization. PMID:27457191

  6. Fundamental and methodological investigations for the improvement of elemental analysis by inductively coupled plasma mass soectrometry

    SciTech Connect

    Ebert, Christopher Hysjulien

    2012-01-01

    This dissertation describes a variety of studies meant to improve the analytical performance of inductively coupled plasma mass spectrometry (ICP-MS) and laser ablation (LA) ICP-MS. The emission behavior of individual droplets and LA generated particles in an ICP is studied using a high-speed, high frame rate digital camera. Phenomena are observed during the ablation of silicate glass that would cause elemental fractionation during analysis by ICP-MS. Preliminary work for ICP torch developments specifically tailored for the improvement of LA sample introduction are presented. An abnormal scarcity of metal-argon polyatomic ions (MAr{sup +}) is observed during ICP-MS analysis. Evidence shows that MAr{sup +} ions are dissociated by collisions with background gas in a shockwave near the tip of the skimmer cone. Method development towards the improvement of LA-ICP-MS for environmental monitoring is described. A method is developed to trap small particles in a collodion matrix and analyze each particle individually by LA-ICP-MS.

  7. Optimization of inductively coupled plasma deep etching of GaN and etching damage analysis

    NASA Astrophysics Data System (ADS)

    Qiu, Rongfu; Lu, Hai; Chen, Dunjun; Zhang, Rong; Zheng, Youdou

    2011-01-01

    Inductively coupled plasma (ICP) etching of GaN with an etching depth up to 4 μm is systemically studied by varying ICP power, RF power and chamber pressure, respectively, which results in etch rates ranging from ∼370 nm/min to 900 nm/min. The surface morphology and damages of the etched surface are characterized by optical microscope, scanning electron microscope, atomic force microscopy, cathodoluminescence mapping and photoluminescence (PL) spectroscopy. Sub-micrometer-scale hexagonal pits and pillars originating from part of the structural defects within the original GaN layer are observed on the etched surface. The density of these surface features varies with etching conditions. Considerable reduction of PL band-edge emission from the etched GaN surface indicates that high-density non-radiative recombination centers are created by ICP etching. The density of these non-radiative recombination centers is found largely dependent on the degree of physical bombardments, which is a strong function of the RF power applied. Finally, a low-surface-damage etch recipe with high ICP power, low RF power, high chamber pressure is suggested.

  8. Langmuir Probe Measurements in an Inductively Coupled Ar/CF4 Plasmas

    NASA Technical Reports Server (NTRS)

    Rao, M. V. V. S.; Meyyappan, M.; Sharma, S. P.; Arnold, James O. (Technical Monitor)

    2000-01-01

    Technological advancement in the microelectronics industry requires an understanding of the physical and chemical processes occurring in plasmas of fluorocarbon gases, such as carbon tetrafluoride (CF4) which is commonly used as an etchant, and their mixtures to optimize various operating parameters. In this paper we report data on electron number density (ne), electron temperature'(Te), electron energy distribution function (EEDF), mean electron energy, ion number density (ni), and plasma potential (Vp) measured by using Langmuir probe in an inductively coupled 13.56 MHz radio frequency plasmas generated in 50%Ar:50%CF4 mixture in the GEC cell. The probe data were recorded at various radial positions providing radial profiles of these plasma parameters at 10-50 mTorr pressures and 200 W and 300 W of RF power. Present measurements indicate that the electron and ion number densities increase with increase in pressure and power. Whereas the plasma potential and electron temperature decrease with increase in pressure, and they weakly depend on RF power. The radial profiles exhibit that the electron and ion number densities and the plasma potential peak at the center of the plasma with an exponential fall away from it, while the electron temperature has a minimum at the center and it increases steadily towards the electrode edge. The EEDFs have a characteristic drop near the low energy end at all pressures and pressures and their shapes represent non-Maxwellian plasma and exhibit more like Druyvesteyn energy distribution.v

  9. Measurements of collisionless heating effects in the H-mode of an inductively coupled plasma system

    NASA Astrophysics Data System (ADS)

    Zaka-Ul-Islam, Mujahid; Graham, Bill; Gans, Timo; Niemi, Kari; O'Connell, Deborah

    2013-09-01

    Inductively coupled plasma systems (ICPs) for processing applications are often operated at low pressures, in the near-collisionless regime. In this regime, the electron mean free path is comparable or larger than the plasma dimensions. The electron dynamics in such ICPs has been investigated here, using phase and space resolved optical emission spectroscopy (PROES) and Langmuir probe measurements. The PROES measurements are also used to calculate the Fourier harmonics components of the 2D excitation (in the radial axial plane). The experimental system is a standard GEC cell with the axial gap of ~4 cm, powered by 13.56 MHz RF power supply. The gas pressure was varied between 0.5 - 2 Pa. The PROES measurements and Fourier harmonics components confirm many of the previous simulation results in comparable operational regimes. The results show that in the 2D (radial-axial) plane, the plasma power is deposited in a spatially non-uniform and non-linear manner, with axial layers of positive and negative power absorption. The contribution of these nonlinear effects decreases with an increase in the pressure, as observed in previous experimental and simulation results.

  10. An inductively coupled plasma source for the Gaseous Electronics Conference RF Reference Cell

    SciTech Connect

    Miller, P.A.; Hebner, G.A.; Greenberg, K.E.; Pochan, P.D.; Aragon, B.P.

    1995-07-01

    In order to extend the operating range of the GEC RF Reference Cell, the authors developed an inductively coupled plasma source that replaced the standard parallel-plate upper-electrode assembly. Voltage and current probes, Langmuir probes, and an 80 GHz interferometer provided information on plasmas formed in argon, chlorine, and nitrogen at pressures from 0.1 Pa to 3 Pa. For powers deposited in the plasma from 20 W to 300 W, the source produced peak electron densities between 10{sup 10}/cm{sup 3} and 10{sup 12}/cm{sup 3} and electron temperatures near 4 eV. The electron density peaked on axis with typical full-width at half maximum of 7 cm to 9 cm. Discharges in chlorine and nitrogen had bimodal operation that was clearly evident from optical emission intensity. A dim mode occurred at low power and a bright mode at high power. The transition between modes had hysteresis. After many hours of high-power operation, films formed on electrodes and walls of one Cell. These deposits affected the dim-to-bright mode transition, and also apparently caused generation of hot electrons and increased the plasma potential.

  11. Determination of mercury in whole blood and urine by inductively coupled plasma mass spectrometry.

    PubMed

    Fong, Bonnie Mei Wah; Siu, Tak Shing; Lee, Joseph Sai Kit; Tam, Sidney

    2007-06-01

    The conventional method for the determination of mercury in clinical samples is cold vapor atomic absorption spectrometry. Sample digestion or pretreatment require large sample volume and long sample preparation time. The inductively coupled plasma mass spectrometry (ICP-MS) method developed in this study requires only 100 microL of sample with practically no preparation, except for dilution with diluent. Significant savings in sample volumes, reagents, technician time, and analysis time are realized. Among different types of diluents, the one containing acid, tert-butanol, and potassium dichromate gave the best results to remove the mercury memory effect. The interassay precisions for whole blood and urine were < 5% and < 8%, respectively, and the intra-assay precisions were < 3% and < 7%, respectively. The lower limits of detection were 0.13, 0.17, and 0.26 microg/L for aqueous standard, urine, and whole blood, respectively. The developed ICP-MS method correlated well with the atomic absorption method and can offer an alternative to the atomic absorption method for mercury analysis with less sample volume requirement as well as shorter analysis time. PMID:17579973

  12. Determination of metals in Brazilian soils by inductively coupled plasma mass spectrometry.

    PubMed

    de Carvalho, Rui M; dos Santos, Jéssica A; Silva, Jessee A S; do Prado, Thiago G; da Fonseca, Adriel Ferreira; Chaves, Eduardo S; Frescura, Vera L A

    2015-08-01

    The concentration of metals in Brazilian soil under no-tillage (NT) and an area under native vegetation (NV) was determined by inductively coupled plasma mass spectrometry. The applied method was based on microwave-assisted acid digestion using HNO3, HCl, H2O2, and HF. The accuracy of the method was evaluated by analyzing two certified reference materials (BCR-142 and RS-3). The relative standard deviation for all target elements was below 8% indicating an adequate precision and the limit of detection ranged from 0.03 μg g(-1) (Cd) to 24.0 μg g(-1) (Fe). The concentrations of Al, As, Ba, Cd, Cu, Fe, Mg, Mn, Ni, Pb, Sr, and Zn in the different layers (0-10, 10-20, 20-40, and 40-60 cm) were determined in two types of soils, located in Paraná State in Brazil. The soil layers analysis revealed a different behavior of metals concentrations in soil samples under NT and NV. The obtained results showed a clear impact of anthropogenic action with respect to specific metals due to many years of uncontrolled application rates of limestone and phosphate fertilizers. PMID:26220781

  13. Using inductively coupled plasma-mass spectrometry for calibration transfer between environmental CRMs.

    PubMed

    Turk, G C; Yu, L L; Salit, M L; Guthrie, W F

    2001-06-01

    Multielement analyses of environmental reference materials have been performed using existing certified reference materials (CRMs) as calibration standards for inductively coupled plasma-mass spectrometry. The analyses have been performed using a high-performance methodology that results in comparison measurement uncertainties that are significantly less than the uncertainties of the certified values of the calibration CRM. Consequently, the determined values have uncertainties that are very nearly equivalent to the uncertainties of the calibration CRM. Several uses of this calibration transfer are proposed, including, re-certification measurements of replacement CRMs, establishing traceability of one CRM to another, and demonstrating the equivalence of two CRMs. RM 8704, a river sediment, was analyzed using SRM 2704, Buffalo River Sediment, as the calibration standard. SRM 1632c, Trace Elements in Bituminous Coal, which is a replacement for SRM 1632b, was analyzed using SRM 1632b as the standard. SRM 1635, Trace Elements in Subbituminous Coal, was also analyzed using SRM 1632b as the standard. PMID:11451248

  14. Inductively coupled plasma mass spectrometry determination of metals in honeybee venom.

    PubMed

    Kokot, Zenon J; Matysiak, Jan

    2008-11-01

    Inductively coupled plasma mass spectrometry (ICP-MS) technique was used to analyze the contamination of selected 20 metals in 32 samples of honeybee venom and to demonstrate differences in the content of these elements. Among the analyzed metal microelements (Al, Co, Cu, Zn, Mn, Mo, B, V, Sr and Ni), macro-elements (Ca, Mg, K and Na) and toxic metals (As, Ba, Pb, Cd, Sb and Cr) were identified. The presented results showed that the metal levels in honeybee venom are much lower than the tolerable upper intake levels for the elements. Also the toxic metal contamination is much lower than the permissible levels for drugs established by the United States Pharmacopeia and the European Pharmacopeia. As opposed to the pharmacopeial tests for metals, a multi-element ICP-MS method has been developed. In order to confirm data obtained, the following steps and parameters were taken into account for the validation of the method: calibration verification, recovery, accuracy, precision, detection limit (LOD), quantitation limit (LOQ), spectral and matrix interference and comparison between ICP-MS and GFAAS (graphite furnace atomic absorption spectrometry) for Mn. All steps of validation proved the accuracy of the results. This is most likely the first study in which the metal content in honeybee venom was evaluated by ICP-MS. PMID:18617350

  15. Depleted uranium analysis in blood by inductively coupled plasma mass spectrometry

    USGS Publications Warehouse

    Todorov, T.I.; Xu, H.; Ejnik, J.W.; Mullick, F.G.; Squibb, K.; McDiarmid, M.A.; Centeno, J.A.

    2009-01-01

    In this study we report depleted uranium (DU) analysis in whole blood samples. Internal exposure to DU causes increased uranium levels as well as change in the uranium isotopic composition in blood specimen. For identification of DU exposure we used the 235U/238U ratio in blood samples, which ranges from 0.00725 for natural uranium to 0.002 for depleted uranium. Uranium quantification and isotopic composition analysis were performed by inductively coupled plasma mass spectrometry. For method validation we used eight spiked blood samples with known uranium concentrations and isotopic composition. The detection limit for quantification was determined to be 4 ng L-1 uranium in whole blood. The data reproduced within 1-5% RSD and an accuracy of 1-4%. In order to achieve a 235U/238U ratio range of 0.00698-0.00752% with 99.7% confidence limit a minimum whole blood uranium concentration of 60 ng L??1 was required. An additional 10 samples from a cohort of veterans exposed to DU in Gulf War I were analyzed with no knowledge of their medical history. The measured 235U/ 238U ratios in the blood samples were used to identify the presence or absence of DU exposure within this patient group. ?? 2009 The Royal Society of Chemistry.

  16. Inductively coupled plasma atomic fluorescence spectrometric determination of cadmium, copper, iron, lead, manganese and zinc

    USGS Publications Warehouse

    Sanzolone, R.F.

    1986-01-01

    An inductively coupled plasma atomic fluorescence spectrometric method is described for the determination of six elements in a variety of geological materials. Sixteen reference materials are analysed by this technique to demonstrate its use in geochemical exploration. Samples are decomposed with nitric, hydrofluoric and hydrochloric acids, and the residue dissolved in hydrochloric acid and diluted to volume. The elements are determined in two groups based on compatibility of instrument operating conditions and consideration of crustal abundance levels. Cadmium, Cu, Pb and Zn are determined as a group in the 50-ml sample solution under one set of instrument conditions with the use of scatter correction. Limitations of the scatter correction technique used with the fluorescence instrument are discussed. Iron and Mn are determined together using another set of instrumental conditions on a 1-50 dilution of the sample solution without the use of scatter correction. The ranges of concentration (??g g-1) of these elements in the sample that can be determined are: Cd, 0.3-500; Cu, 0.4-500; Fe, 85-250 000; Mn, 45-100 000; Pb, 5-10 000; and Zn, 0.4-300. The precision of the method is usually less than 5% relative standard deviation (RSD) over a wide concentration range and acceptable accuracy is shown by the agreement between values obtained and those recommended for the reference materials.

  17. Imaging mass spectrometry in biological tissues by laser ablation inductively coupled plasma mass spectrometry.

    PubMed

    Becker, J S; Becker, J Su; Zoriy, M V; Dobrowolska, J; Matucsh, A

    2007-01-01

    Of all the inorganic mass spectrometric techniques, laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) plays a key role as a powerful and sensitive microanalytical technique enabling multi- element trace analysis and isotope ratio measurements at trace and ultratrace level. LA-ICP-MS was used to produce images of detailed regionally-specific element distribution in 20 microm thin sections of different parts of the human brain. The quantitative determination of copper, zinc, lead and uranium distribution in thin slices of human brain samples was performed using matrix-matched laboratory standards via external calibration procedures. Imaging mass spectrometry provides new information on the spatially inhomogeneous element distribution in thin sections of human tissues, for example, of different brain regions (the insular region) or brain tumor tissues. The detection limits obtained for Cu, Zn, Pb and U were in the ng g(-1) range. Possible strategies of LA-ICP-MS in brain research and life sciences include the elemental imaging of thin slices of brain tissue or applications in proteome analysis by combination with matrix-assisted laser desorption/ionization MS to study phospho- and metal- containing proteins will be discussed. PMID:17885277

  18. Effect of low-damage inductively coupled plasma on shallow nitrogen-vacancy centers in diamond

    SciTech Connect

    Fávaro de Oliveira, Felipe; Momenzadeh, S. Ali; Wang, Ya; Denisenko, Andrej; Konuma, Mitsuharu; Markham, Matthew; Edmonds, Andrew M.; Wrachtrup, Jörg

    2015-08-17

    Near-surface nitrogen-vacancy (NV) centers in diamond have been successfully employed as atomic-sized magnetic field sensors for external spins over the last years. A key challenge is still to develop a method to bring NV centers at nanometer proximity to the diamond surface while preserving their optical and spin properties. To that aim we present a method of controlled diamond etching with nanometric precision using an oxygen inductively coupled plasma process. Importantly, no traces of plasma-induced damages to the etched surface could be detected by X-ray photoelectron spectroscopy and confocal photoluminescence microscopy techniques. In addition, by profiling the depth of NV centers created by 5.0 keV of nitrogen implantation energy, no plasma-induced quenching in their fluorescence could be observed. Moreover, the developed etching process allowed even the channeling tail in their depth distribution to be resolved. Furthermore, treating a {sup 12}C isotopically purified diamond revealed a threefold increase in T{sub 2} times for NV centers with <4 nm of depth (measured by nuclear magnetic resonance signal from protons at the diamond surface) in comparison to the initial oxygen-terminated surface.

  19. Acid retardation method in analysis of strongly acidic solutions by inductively coupled plasma mass-spectrometry.

    PubMed

    Seregina, I F; Perevoznik, O A; Bolshov, M A

    2016-10-01

    Acid retardation on the sorbents as a technique for reduction of the acidity of the solutions prior to their analysis by inductively coupled plasma mass spectrometry was proposed and investigated. The proposed scheme provides substantial separation of the analytes and nitric acid, which allows direct introduction of the eluates in plasma without dilution. Two sorbents were examined - AV-17 anion-exchange resin and the Stirosorb 584 sorbent. Sorption and desorption of 38 elements on these sorbents were investigated. The efficiencies of the REEs' sorption on the anion-exchange and neutral sorbents were compared. The higher efficiency of the REEs and HNO3 separation was revealed for the neutral Stirosorb 584 sorbent. It was also found that most elements come out quantitatively of the column filled with the AV-17 resin after pumping 2-4mL of the solution. Wherein, the concentration of nitric acid decreased by 20 times. The anomalous behaviour of Ag, Pb, Th and U on the AV-17 resin was found. These analytes were eluted only after pumping 4 column volumes of deionized water. Na, K, Fe, Al and Li in concentrations within (50-1000mgL(-1)) range did not affect the recovery of REEs. The potential of ARM technique was demonstrate by the analysis of puriss. HNO3 and silverware. ARM enables to avoid dilution of highly acidic solutions prior to their introduction in ICP-MS. PMID:27474322

  20. Effect of low-damage inductively coupled plasma on shallow nitrogen-vacancy centers in diamond

    NASA Astrophysics Data System (ADS)

    Fávaro de Oliveira, Felipe; Momenzadeh, S. Ali; Wang, Ya; Konuma, Mitsuharu; Markham, Matthew; Edmonds, Andrew M.; Denisenko, Andrej; Wrachtrup, Jörg

    2015-08-01

    Near-surface nitrogen-vacancy (NV) centers in diamond have been successfully employed as atomic-sized magnetic field sensors for external spins over the last years. A key challenge is still to develop a method to bring NV centers at nanometer proximity to the diamond surface while preserving their optical and spin properties. To that aim we present a method of controlled diamond etching with nanometric precision using an oxygen inductively coupled plasma process. Importantly, no traces of plasma-induced damages to the etched surface could be detected by X-ray photoelectron spectroscopy and confocal photoluminescence microscopy techniques. In addition, by profiling the depth of NV centers created by 5.0 keV of nitrogen implantation energy, no plasma-induced quenching in their fluorescence could be observed. Moreover, the developed etching process allowed even the channeling tail in their depth distribution to be resolved. Furthermore, treating a 12C isotopically purified diamond revealed a threefold increase in T2 times for NV centers with <4 nm of depth (measured by nuclear magnetic resonance signal from protons at the diamond surface) in comparison to the initial oxygen-terminated surface.

  1. Mode transition in CF{sub 4} + Ar inductively coupled plasma

    SciTech Connect

    Liu, Wei; Gao, Fei; Zhao, Shu-Xia; Li, Xue-Chun; Wang, You-Nian

    2013-12-15

    The E to H mode transitions are studied by a hairpin probe and optical emission spectroscopy in inductively coupled CF{sub 4} + Ar plasmas. Electron density, optical emission intensity of Ar, and the voltage and current are measured during the E to H mode transitions. It is found that the electron density and plasma emission intensity increase continuously at low pressure during the E to H mode transition, while they jump up discontinuously at high pressure. Meanwhile, the transition threshold power and △P (the power interval between E and H mode) increase by increasing the pressure. When the ratio of CF{sub 4} increases, the E to H mode transition happens at higher applied power, and meanwhile, the △P also significantly increases. Besides, the effects of CF{sub 4} gas ratio on the plasma properties and the circuit electrical properties in both pure E and H modes were also investigated. The electron density and plasma emission intensity both decrease upon increasing the ratio of CF{sub 4} at the two modes, due to the stronger electrons loss scheme. The applied voltages at E and H modes both increase as increasing the CF{sub 4} gas ratio, however the applied current at two modes behave just oppositely with the gas ratio.

  2. Comparative Study of Plasma Parameters in Magnetic Pole Enhanced Inductively Coupled Argon Plasmas

    NASA Astrophysics Data System (ADS)

    F., Jan; W. Khan, A.; Saeed, A.; Zakaullah, M.

    2013-04-01

    Langmuir probe measurements of radio frequency (RF) magnetic pole enhanced inductively coupled (MaPE-ICP) argon plasma were accomplished to obtain the electron number densities and electron temperatures. The measurements were carried out with a fixed RF frequency of 13.56 MHz in a pressure range of 7.5 mTorr to 75 mTorr at an applied RF power of 10 W and 100 W. These results are compared with a global (volume average) model. The results show good agreement between theoretical and experimental measurements. The electron number density shows an increasing trend with both RF power and pressure while the electron temperature shows decreasing trend as the pressure increases. The difference in the plasma potential and floating potential as a function of electron temperature measured from the electrical probe and that obtained theoretically shows a linear relation with a small difference in the coefficient of proportionality. The intensity of the emission line at 750.4 nm due to 2p1 → 1s2 (Paschen's notation) transition closely follows the variation of ne with RF power and filling gas pressure. Measured electron energy probability function (EEPF) shows that electron occupation changes mostly in the high-energy tail, which highlights close similarity of 750.4 nm argon line to ne.

  3. Control of plasma density distribution via wireless power transfer in an inductively coupled plasma

    NASA Astrophysics Data System (ADS)

    Lee, Hee-Jin; Lee, Hyo-Chang; Kim, Young-Cheol; Chung, Chin-Wook

    2013-06-01

    With an enlargement of the wafer size, development of large-area plasma sources and control of plasma density distribution are required. To control the spatial distribution of the plasma density, wireless power transfer is applied to an inductively coupled plasma for the first time. An inner powered antenna and an outer resonant coil connected to a variable capacitor are placed on the top of the chamber. As the self-resonance frequency ωr of the resonant coil is adjusted, the power transfer rate from the inner powered coil to the outer resonant coil is changed and the dramatic evolution of the plasma density profile is measured. As ωr of the outer resonant coil changes from the non-resonant condition (where ωr is not the driving angular frequency ωrf) to the resonant condition (where ωr = ωrf), the plasma density profile evolves from a convex shape with maximal plasma density at the radial center into a concave shape with maximal plasma density in the vicinity of the resonant antenna coil. This result shows that the plasma density distribution can be successfully controlled via wireless resonance power transfer.

  4. Direct solid sampling of fire assay beads by spark ablation inductively coupled plasma mass spectrometry

    NASA Astrophysics Data System (ADS)

    Van Hoven, R. L.; Nam, Sang-Ho; Montaser, Akbar; Doughten, M. W.; Dorrzapf, A. F.

    1995-06-01

    A spark-based, solid-sampling cell is described for inductively coupled plasma mass spectrometry (ICP-MS). The cell is devised for the direct sampling of gold and silver beads produced by the classical lead fire assay procedure. The sampler produces a solid aerosol composed of submicron-sized vapor condensates and small (< 2 μm) spherules. In contrast to solution nebulization, the mass spectrum for spark-ICP-MS is relatively free of interfering metal oxide, polyatomic, and multiply-charged ions. The measurement precision is 3% RSD for Pt, Pd, and Rh preconcentrated into fire assay beads, but is 6% RSD for Ir due to its heterogeneous distribution in a silver bead. Detection limits determined for Pt, Pd, Rh, and Ir in fire assay beads range from 0.6 μg/g (Pt) to 1.2 μg/g (Pd). Calibration curves for these elements are linear up to the highest concentration in the bead studied (2000 μg/g). The quantitative potential of the method is evaluated using the South African Reference Material (SARM-7) geologic standard.

  5. Transport and trapping of dust particles in a potential well created by inductively coupled diffused plasmas.

    PubMed

    Choudhary, Mangilal; Mukherjee, S; Bandyopadhyay, P

    2016-05-01

    A versatile linear dusty (complex) plasma device is designed to study the transport and dynamical behavior of dust particles in a large volume. Diffused inductively coupled plasma is generated in the background of argon gas. A novel technique is used to introduce the dust particles in the main plasma by striking a secondary direct current glow discharge. These dust particles are found to get trapped in an electrostatic potential well, which is formed due to the combination of the ambipolar electric field caused by diffusive plasma and the field produced by the charged glass wall of the vacuum chamber. According to the requirements, the volume of the dust cloud can be controlled very precisely by tuning the plasma and discharge parameters. The present device can be used to address the underlying physics behind the transport of dust particles, self-excited dust acoustic waves, and instabilities. The detailed design of this device, plasma production and characterization, trapping and transport of the dust particle, and some of the preliminary experimental results are presented. PMID:27250421

  6. Transport and trapping of dust particles in a potential well created by inductively coupled diffused plasmas

    NASA Astrophysics Data System (ADS)

    Choudhary, Mangilal; Mukherjee, S.; Bandyopadhyay, P.

    2016-05-01

    A versatile linear dusty (complex) plasma device is designed to study the transport and dynamical behavior of dust particles in a large volume. Diffused inductively coupled plasma is generated in the background of argon gas. A novel technique is used to introduce the dust particles in the main plasma by striking a secondary direct current glow discharge. These dust particles are found to get trapped in an electrostatic potential well, which is formed due to the combination of the ambipolar electric field caused by diffusive plasma and the field produced by the charged glass wall of the vacuum chamber. According to the requirements, the volume of the dust cloud can be controlled very precisely by tuning the plasma and discharge parameters. The present device can be used to address the underlying physics behind the transport of dust particles, self-excited dust acoustic waves, and instabilities. The detailed design of this device, plasma production and characterization, trapping and transport of the dust particle, and some of the preliminary experimental results are presented.

  7. Biofuel Cell Based on Microscale Nanostructured Electrodes with Inductive Coupling to Rat Brain Neurons

    PubMed Central

    Andoralov, Viktor; Falk, Magnus; Suyatin, Dmitry B.; Granmo, Marcus; Sotres, Javier; Ludwig, Roland; Popov, Vladimir O.; Schouenborg, Jens; Blum, Zoltan; Shleev, Sergey

    2013-01-01

    Miniature, self-contained biodevices powered by biofuel cells may enable a new generation of implantable, wireless, minimally invasive neural interfaces for neurophysiological in vivo studies and for clinical applications. Here we report on the fabrication of a direct electron transfer based glucose/oxygen enzymatic fuel cell (EFC) from genuinely three-dimensional (3D) nanostructured microscale gold electrodes, modified with suitable biocatalysts. We show that the process underlying the simple fabrication method of 3D nanostructured electrodes is based on an electrochemically driven transformation of physically deposited gold nanoparticles. We experimentally demonstrate that mediator-, cofactor-, and membrane-less EFCs do operate in cerebrospinal fluid and in the brain of a rat, producing amounts of electrical power sufficient to drive a self-contained biodevice, viz. 7 μW cm−2 in vitro and 2 μW cm−2 in vivo at an operating voltage of 0.4 V. Last but not least, we also demonstrate an inductive coupling between 3D nanobioelectrodes and living neurons. PMID:24253492

  8. Vibrational kinetics in Cl2 and O2 low-pressure inductively-coupled plasmas

    NASA Astrophysics Data System (ADS)

    Booth, Jean-Paul; Foucher, Mickael; Marinov, Daniil; Chabert, Pascal; Annusova, Anna; Guerra, Vasco; Agarwal, Ankur; Rauf, Shahid

    2015-09-01

    Low energy electron interactions with molecules via resonances can cause vibrational excitation (affecting chemical kinetics), electron energy loss and modification of the EEDF. However, with the exception of N2 and H2 plasmas, very little attention has been paid to this subject. We have implemented a novel high-sensitivity ultra-broadband UV absorption bench, allowing spectra to be recorded with noise as low as 2×10-5 over a 250 nm wavelength range, and recording of complete vibronic bands. We applied this to radiofrequency inductively-coupled plasmas in low pressure (5-50 mTorr) pure O2 and pure Cl2. In O2 plasmas we surprisingly observe highly vibrationally excited O2 (v'' up to 18) via B-X Schumann-Runge bands. Cl2 molecules show a broad UV absorption spectrum in the region 250-400 nm, with distinctly different absorption spectra for vibrationally excited molecules. However, only a small fraction of the Cl2 molecules were observed in vibrationally excited states and the vibrational temperature is close to equilibrium with the local gas translational temperature (up to 1000 K), in contrast to O2. We are currently working on global models with vibrational kinetics to explain these results. Work supported by LABEX Plas@par (ANR-11-IDEX-0004-02), and Applied Materials.

  9. The Kalman filter approach to inductively coupled plasma atomic emission spectrometry

    NASA Astrophysics Data System (ADS)

    Van Veen, E. H.; Bosch, S.; De Loos-Vollebregt, M. T. C.

    1994-07-01

    This article is an electronic publication in Spectrochimica Acta Electronica (SAE), the electronic section of Spectrochimica Acta Part B (SAB). The hardcopy text, comprising the main article and two appendices, is accompanied by a disk containing the compiled program, a reference manual and data files. The work deals with data handling in inductively coupled plasma atomic emission spectrometry (ICP-AES). With this technique, the analyte signal is superimposed on a background signal. When separating the signals by manual or automated three-point background correction, there are many instances in which the data reduction fails. Based on scans recorded in a fast-scanning mode and on a library of pure-component scans, the Kaiman filter approach models the emission in the spectral window (about 100 pm) of the analyte and mathematically solves the problem of background correction. By using a criterion-based algorithm to correct for optical instability, the uncertainty in the determination of the interferent line signal is eliminated. Therefore, the present filter implementation yields more accurate and precise results, especially in the case of line overlap. The Kalman filter Approach to Atomic Spectrometry (KAAS) software automatically processes Perkin-Elmer Plasma 1000/2000 text files, but can also handle ASCII data files. Practical and comprehensive examples are given to evoke the "Kalman filter feeling" in the crucial step of creating the emission model.

  10. Plasma Characteristics Using Superimposed Dual Frequency Inductively Coupled Plasma Source for Next Generation Device Processing.

    PubMed

    Lee, Seung Min; Lee, Chul Hee; Kim, Tae Hyung; Yeom, Geun Young; Kim, Kyong Nam

    2015-11-01

    U-shaped inductively coupled plasma (ICP) source was investigated as a linear plasma source for the next generation roll-to-toll flexible display processing. For the radio frequency power to the source, the dual frequency composed of 13.56 MHz and 2 MHz was used and the effect of dual frequency to the U-shaped ICP source on the plasma density, electron temperature, and plasma uniformity was investigated. As the operating condition, 200 mTorr Ar was used without operating turbo pumps. The use of superimposed dual frequency composed of 13.56 MHz + 2 MHz instead the single frequency of 13.56 MHz increased the plasma density slightly at the same total power. In addition, the addition of 2 MHz rf power to 0.4 kW while maintaining 1 kW 13.56 MHz rf power not only decreased electron temperature but also improved both the plasma uniformity and the process uniformity measured by photoresist etching. Therefore, by using the dual frequency to the U-shaped ICP source, not only the plasma density but also plasma uniformity could be improved in addition to the decrease of possible damage to the substrate. PMID:26726573

  11. Studies of selenium and xenon in inductively coupled plasma mass spectrometry

    SciTech Connect

    Bricker, T.

    1994-07-27

    Since its development, inductively coupled plasma mass spectrometry (ICP-MS) has been a widely used analytical technique. ICP-MS offers low detection limits, easy determination of isotope ratios, and simple mass spectra from analyte elements. ICP-MS has been successfully employed for many applications including geological, environmental, biological, metallurgical, food, medical, and industrial. One specific application important to many areas of study involves elemental speciation by using ICP-MS as an element specific detector interfaced to liquid chromatography. Elemental speciation information is important and cannot be obtained by atomic spectrometric methods alone which measure only the total concentration of the element present. Part 1 of this study describes the speciation of selenium in human serum by size exclusion chromatography (SEC) and detection by ICP-MS. Although ICP-MS has been widely sued, room for improvement still exists. Difficulties in ICP-MS include noise in the background, matrix effects, clogging of the sampling orifice with deposited solids, and spectral interference caused by polyatomic ions. Previous work has shown that the addition of xenon into the central channel of the ICP decreases polyatomic ion levels. In Part 2 of this work, a fundamental study involving the measurement of the excitation temperature is carried out to further understand xenon`s role in the reduction of polyatomic ions. 155 refs.

  12. Methods for detecting and correcting inaccurate results in inductively coupled plasma-atomic emission spectrometry

    DOEpatents

    Chan, George C. Y.; Hieftje, Gary M.

    2010-08-03

    A method for detecting and correcting inaccurate results in inductively coupled plasma-atomic emission spectrometry (ICP-AES). ICP-AES analysis is performed across a plurality of selected locations in the plasma on an unknown sample, collecting the light intensity at one or more selected wavelengths of one or more sought-for analytes, creating a first dataset. The first dataset is then calibrated with a calibration dataset creating a calibrated first dataset curve. If the calibrated first dataset curve has a variability along the location within the plasma for a selected wavelength, errors are present. Plasma-related errors are then corrected by diluting the unknown sample and performing the same ICP-AES analysis on the diluted unknown sample creating a calibrated second dataset curve (accounting for the dilution) for the one or more sought-for analytes. The cross-over point of the calibrated dataset curves yields the corrected value (free from plasma related errors) for each sought-for analyte.

  13. Determination of rare earth elements in environmental materials by inductively coupled plasma mass spectrometry

    SciTech Connect

    Panday, V.K.; Hoppstock, K.; Becker, J.S.; Dietze, H.J.

    1996-09-01

    Despite the fact that rare earth elements (REE) have found increasing use in modern technology only few data are available on their concentrations in biological and environmental samples. Inductively coupled plasma mass spectrometry (ICP-MS) has been employed to study the concentration of rare earth elements (REE) in various environmental materials (e.g., pine needles, mussel tissue, apple leaves) available from National Institute of Standards and Technology (NIST), the Bureau of European Communities (BCR), and the German Environmental Specimens Bank. After the decomposition of the environmental samples with HNO{sub 3}, the REE (present mostly in the ng/g-range) were separated from the matrix and simultaneously preconcentrated using liquid-liquid extraction with bis(2-ethyl hexyl)-ortho-phosphoric acid (HDEHP) in toluene as a selective reagent at pH = 2 and subsequent back extraction of the elements into the aqueous by 6M HNO{sub 3}. Recoveries of better 90% were obtained for almost all REE. A Perkin Elmer/Sciex ELAN 5000 ICP-MS and HR-ICP-MS ELEMENT from Finnigan MAT were used for quantitative analysis (by external calibration and ID-ICP-MS) of REE. The results of determination of REE concentrations agree well with the data available on some of these materials. Further supplement information on the contents of various REE in these materials.

  14. The survival of gunshot residues in cremated bone: an inductively coupled plasma optical emission spectrometry study.

    PubMed

    Amadasi, Alberto; Merli, Daniele; Brandone, Alberto; Poppa, Pasquale; Gibelli, Daniele; Cattaneo, Cristina

    2013-07-01

    Gunshot residue (GSR) has been sought and demonstrated on many types of material and with many techniques. Inductively coupled plasma optical emission spectrometry (ICP-OES) could be a useful method on difficult substrates, but a systematic study on burnt material has never been performed. Hence, this study aims at evaluating the usefulness and reliability of this method on burnt samples. Sixteen adult bovine ribs (eight with soft tissues, eight totally skeletonized) were shot using two kinds of projectile (both 9 mm full metal-jacketed or unjacketed). Then, every sample was led to complete calcination in an electric oven. The area of the gunshot entrance wound was swabbed and analyzed by ICP-OES; the results were also correlated with a previously published parallel study by scanning electron microscopy (SEM) equipped with an SEM-energy dispersive X-ray analyzer. ICP-OES proved to be very sensitive and reliable even on degraded material and can be an appropriate nondestructive method for detecting residues on difficult and delicate substrates such as burnt bone. PMID:23692414

  15. ''SensArray'' voltage sensor analysis in an inductively coupled plasma

    SciTech Connect

    Titus, M. J.; Hsu, C. C.; Graves, D. B.

    2010-01-15

    A commercially manufactured PlasmaVolt sensor wafer was studied in an inductively coupled plasma reactor in an effort to validate sensor measurements. A pure Ar plasma at various powers (25-420 W), for a range of pressures (10-80 mT), and bias voltages (0-250 V) was utilized. A numerical sheath simulation was simultaneously developed in order to interpret experimental results. It was found that PlasmaVolt sensor measurements are proportional to the rf-current through the sheath. Under conditions such that the sheath impedance is dominantly capacitive, sensor measurements follow a scaling law derived from the inhomogeneous sheath model of Lieberman and Lichtenberg, [Principles of Plasma Discharges and Materials Processing (Wiley, New York, 2005)]. Under these conditions, sensor measurements are proportional to the square root of the plasma density at the plasma-sheath interface, the one-fourth root of the electron temperature, and the one-fourth root of the rf bias voltage. When the sheath impedance becomes increasingly resistive, the sensor measurements deviate from the scaling law and tend to be directly proportional to the plasma density. The measurements and numerical sheath simulation demonstrate the scaling behavior as a function of changing sheath impedance for various plasma conditions.

  16. 200-mm-diameter neutral beam source based on inductively coupled plasma etcher and silicon etching

    SciTech Connect

    Kubota, Tomohiro; Nukaga, Osamu; Ueki, Shinji; Sugiyama, Masakazu; Inamoto, Yoshimasa; Ohtake, Hiroto; Samukawa, Seiji

    2010-09-15

    The authors developed a neutral beam source consisting of a 200-mm-diameter inductively coupled plasma etcher and a graphite neutralization aperture plate based on the design of a neutral beam source that Samukawa et al. [Jpn. J. Appl. Phys., Part 2 40, L779 (2001)] developed. They measured flux and energy of neutral particles, ions, and photons using a silicon wafer with a thermocouple and a Faraday cup and calculated the neutralization efficiency. An Ar neutral beam flux of more than 1 mA/cm{sup 2} in equivalent current density and a neutralization efficiency of more than 99% were obtained. The spatial uniformity of the neutral beam flux was within {+-}6% within a 100 mm diameter. Silicon etching using a F{sub 2}-based neutral beam was done at an etch rate of about 47 nm/min, while Cl{sub 2}-based neutral beam realized completely no undercut. The uniformity of etch rate was less than {+-}5% within the area. The etch rate increased by applying bias power to the neutralization aperture plate, which shows that accelerated neutral beam was successfully obtained. These results indicate that the neutral beam source is scalable, making it possible to obtain a large-diameter and uniform neutral beam, which is inevitable for application to mass production.

  17. Improving sensitivity for microchip electrophoresis interfaced with inductively coupled plasma mass spectrometry using parallel multichannel separation.

    PubMed

    Cheng, Heyong; Liu, Jinhua; Xu, Zigang; Wang, Yuanchao; Ye, Meiying

    2016-08-26

    We reported sensitivity enhancement using multichannel parallel separation for microchip electrophoresis hyphenated with inductively coupled plasma mass spectrometry (MCE-ICP-MS) in this study. By using 2-20 array lanes for parallel separation, the sensitivity of the MCE-ICP-MS system was proportionally improved by 2-20 folds. No significantly adverse effect of parallel separation on column efficiency and resolution was observed. Rapid separation of Hg(2+) and methylmercuric (MeHg) ion within 36s under an electric field of 800Vcm(-1) was achieved in the 2-cm twenty-channels with a background electrolyte of 5mmolL(-1) borate buffer (pH 9.2). Detection limits of Hg(2+) and MeHg by the proposed system were decreased to 6.8-7.1ngL(-1). Good agreement between determined values and certified values of a certified reference fish was obtained with recoveries ranged between 94-98%. All results prove its advantages including high sensitivity, high efficiency and low operation cost, which are beneficial to routine analysis of metal speciation in environmental, biological and food fields. PMID:27488720

  18. Introduction of organic solvents into inductively coupled plasmas by ultrasonic nebulization with cryogenic desolvation

    SciTech Connect

    Wiederin, D.R.; Houk, R.S.; Winge, R.K.; D'Silva, A.P. )

    1990-06-01

    A two-step desolvation system for a continuous-flow ultrasonic nebulizer reduced the solvent load on an argon inductively coupled plasma (ICP). The aerosol was first heated above the boiling point of the solvent. Subsequently, solvent vapor was removed in two condensers kept at {minus}10{degree}C and {approx equal}{minus}80{degree}C. No special plasma ignition procedures were required; a change of solvent did not cause plasma instability. The plasma was stable to a forward power as low as 0.5 kW when methanol, acetone, acetonitrile, or ethanol was nebulized. The plasma could not be sustained while organic solvents were ultrasonically nebulized without at least partial desolvation. Detection limits for metals ranged from 0.2 {mu}g L{sup {minus}1} for Fe to 5 {mu}g L{sup {minus}1} for Pb. The detection limits for each element were approximately the same regardless of the organic solvent used and were comparable to those obtained during ultrasonic nebulization of aqueous solutions. With a forward power of 1.0 kW, molecular band emission from C{sub 2} was about 25 times less than when the aerosol was partially desolvated using a condensation temperature of {minus}10{degree}C.

  19. Heteroepitaxial growth of wafer scale highly oriented graphene using inductively coupled plasma chemical vapor deposition

    NASA Astrophysics Data System (ADS)

    Gao, Libo; Xu, Hai; Li, Linjun; Yang, Yang; Fu, Qiang; Bao, Xinhe; Loh, Kian Ping

    2016-06-01

    The chemical vapor deposition (CVD) of graphene on Cu has attracted much attention because of its industrial scalability. Herein, we report inductively coupled plasma-assisted CVD of epitaxially grown graphene on (111)-textured Cu film alloyed with a small amount of Ni, where large area high quality graphene film can be grown in less than 5 min at 800 °C, thus affording industrial scalability. The epitaxially grown graphene films on (111)-textured Cu contain grains which are predominantly aligned with the Cu lattice and about 10% of 30°-rotated grains (anti-grains). Such graphene films are exclusively monolayer and possess good electrical conductivity, high carrier mobility, and room temperature quantum Hall effect. Magnetoresistance measurements reveal that the reduction of the grain sizes from 150 nm to 50 nm produce increasing Anderson localization and the appearance of a transport gap. Owing to the presence of grain boundaries in these anti-grains, epitaxially grown graphene films possess n-type characteristics and exhibit ultra-high sensitivity to adsorbates.

  20. Wireless thin film transistor based on micro magnetic induction coupling antenna.

    PubMed

    Jun, Byoung Ok; Lee, Gwang Jun; Kang, Jong Gu; Kim, Seunguk; Choi, Ji-Woong; Cha, Seung Nam; Sohn, Jung Inn; Jang, Jae Eun

    2015-01-01

    A wireless thin film transistor (TFT) structure in which a source/drain or a gate is connected directly to a micro antenna to receive or transmit signals or power can be an important building block, acting as an electrical switch, a rectifier or an amplifier, for various electronics as well as microelectronics, since it allows simple connection with other devices, unlike conventional wire connections. An amorphous indium gallium zinc oxide (α-IGZO) TFT with magnetic antenna structure was fabricated and studied for this purpose. To enhance the induction coupling efficiency while maintaining the same small antenna size, a magnetic core structure consisting of Ni and nanowires was formed under the antenna. With the micro-antenna connected to a source/drain or a gate of the TFT, working electrical signals were well controlled. The results demonstrated the device as an alternative solution to existing wire connections which cause a number of problems in various fields such as flexible/wearable devices, body implanted devices, micro/nano robots, and sensors for the 'internet of things' (IoT). PMID:26691929

  1. On-line elemental analysis of fossil fuel process streams by inductively coupled plasma spectrometry

    SciTech Connect

    Chisholm, W.P.

    1995-06-01

    METC is continuing development of a real-time, multi-element plasma based spectrometer system for application to high temperature and high pressure fossil fuel process streams. Two versions are under consideration for development. One is an Inductively Coupled Plasma system that has been described previously, and the other is a high power microwave system. The ICP torch operates on a mixture of argon and helium with a conventional annular swirl flow plasma gas, no auxiliary gas, and a conventional sample stream injection through the base of the plasma plume. A new, demountable torch design comprising three ceramic sections allows bolts passing the length of the torch to compress a double O-ring seal. This improves the reliability of the torch. The microwave system will use the same data acquisition and reduction components as the ICP system; only the plasma source itself is different. It will operate with a 750-Watt, 2.45 gigahertz microwave generator. The plasma discharge will be contained within a narrow quartz tube one quarter wavelength from a shorted waveguide termination. The plasma source will be observed via fiber optics and a battery of computer controlled monochromators. To extract more information from the raw spectral data, a neural net computer program is being developed. This program will calculate analyte concentrations from data that includes analyte and interferant spectral emission intensity. Matrix effects and spectral overlaps can be treated more effectively by this method than by conventional spectral analysis.

  2. [Analysis of Trace Inorganic Elements in Castor Oil by Inductively Coupled Plasma Mass Spectrometry].

    PubMed

    Li, Tan-ping; Xie, Hua-lin; Nie, Xi-du

    2015-10-01

    A method for the determination of Na, Mg, Si, P, K, Ca, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Sr, Mo, Cd, Hg and Pb in castor oil after direct dilution with ethanol by inductively coupled plasma mass spectrometry (ICP-MS) was established. The sample was diluted by ethanol before ICP-MS determination. The condensation and deposition of high concentrations of carbon in mass cone interface and ion lens, which will decrease the sensitivity of element analysis, were avoided effectively by introducing O2 to plasma. The mass spectral interferences were eliminated by octopole reaction system (ORS). The matrix effects were calibrated to using Sc, Ge, Rh and Ir as internal standard elements. Au standard solution, which could form amalgam alloy with Hg, was dropped to eliminate the memory effect of Hg. The results show that the correlation coefficient for analyte is no less than 0.999 5, the detection limits is in the range of 0.06 - 20.1 ng x L(-1), the recovery is in the range of 990.4% - 110.2%, and the RSD is less than 4.8%. This method was very fast, simple and accurate to simultaneously analyze multi-elements in castor oil. PMID:26904837

  3. Nanocrystalline silicon embedded in silicon suboxide synthesized in high-density inductively coupled plasma

    NASA Astrophysics Data System (ADS)

    Zhou, H. P.; Xu, S.; Xu, M.; Xiao, S. Q.; Xiang, Y.

    2015-11-01

    A two-phase material system of nanocrystalline silicon (nc-Si) embedded in a dielectric matrix of silicon suboxide (SiO x ) is fundamentally and technologically significant for the photonic and photovoltaic device such as light emission diode and solar cells. nc-Si in amorphous SiO x has been synthesized by means of the low-frequency (460 kHz) inductively coupled plasma (LFICP) of SiH4  +  CO2  +  H2 without the common route of high hydrogen dilution. The chemical composition, microstructures and optical properties of the complex material system are tuned by the reactive gas flow rate ratio of CO2/SiH4. nc-Si embedded in amorphous SiO x due to the phase separation are observed by means of SEM and TEM characterization tools. The crystalline volume fraction in nc-SiO x :H is determined by the density of the embedded nc-Si particles and the occurrence of the a-SiO x encapsulating shell layer. The bond configuration analysis shows the concurrent oxygenation and dehydrogenation process with the incorporation of oxygen. The underlying mechanism in forming the two-phase complex material system and the phase evolution with the reactive gas flow rate ratio are discussed in terms of the unique features of the utilized high-density LFICP.

  4. Optimization of operating parameters for inductively coupled plasma mass spectrometry: A computational study

    NASA Astrophysics Data System (ADS)

    Aghaei, Maryam; Lindner, Helmut; Bogaerts, Annemie

    2012-10-01

    An inductively coupled plasma, connected to a mass spectrometer interface, is computationally investigated. The effect of pressure behind the sampler, injector gas flow rate, auxiliary gas flow rate, and applied power is studied. There seems to be an optimum range of injector gas flow rate for each setup which guaranties the presence and also a proper length of the central channel in the torch. Moreover, our modeling results show that for any specific purpose, it is possible to control that either only the central gas flow passes through the sampler orifice or that it is accompanied by the auxiliary gas flow. It was also found that depending on geometry, the variation of outgoing gas flow rate is much less than the variation of the injector gas flow rate and this causes a slightly higher pressure inside the torch. The general effect of increasing the applied power is a rise in the plasma temperature, which results in a higher ionization in the coil region. However, the negative effect is reducing the length of the cool central channel which is important to transfer the sample substances to the sampler. Using a proper applied power can enhance the efficiency of the system. Indeed, by changing the gas path lines, the power can control which flow (i.e., only from injector gas or also from the auxiliary gas) goes to the sampler orifice. Finally, as also reported from experiments in literature, the pressure behind the sampler has no dramatic effect on the plasma characteristics.

  5. Analysis of fertilizers for major, micro, and trace elements by inductively coupled plasma emission spectroscopy

    NASA Astrophysics Data System (ADS)

    Jones, J. B., Jr.

    The concentrations of nine elements (B, Ca, Cu, Fe, K, Mg, Mn, P, and Zn) in 34 Magruder Fertilizer Standards were determined by inductively coupled plasma (ICP) emission spectroscopy, and the results compared favorably with the known concentrations for all the elements. In addition to these nine fertilizer elements, six others (AI, Cd, Cr, Na, Ni, and Pb) were determined in the same analysis, although results could only be compared to similar analyses made by two other laboratories employing ICP. All 15 elements were also determined in 12 spent acids used to manufacture liquid fertilizer and analysis results compared among the three laboratories. Analysis by ICP spectroscopy of fertilizer materials with wide ranges of elemental contents was found to be a rapid analysis technique which can give comparable results with those obtained by the more laborious AOAC procedures as well as the opportunity to determine other than only the important fertilizer elements. Collaborative study is recommended for ICP determination of the elements of importance in fertilizers for adaptation of the ICP technique by the Association of Official Analytical Chemists.

  6. Testing of inductively coupled Eddy current position sensor of diverse safety rod in sodium

    SciTech Connect

    Vijayashree, R.; Veeraswamy, R.; Nashine, B. K.; Dash, S. K.; Sharma, P.; Rajan, K. K.; Vijayakumar, G.; Rao, C. B.; Sosamma, S.; Kalyanasundaram, P.

    2011-07-01

    Prototype Fast Breeder Reactor (PFBR) is 500 MWe sodium cooled reactor under construction at Kalpakkam (India)). To improve the reliability of shutdown, Diverse Safety Rods (DSRs) are used in-addition to normal Control and Safety rods. During reactor operating condition, the DSR is parked above the active core and held in its top position by an electromagnet. In the event of a scram signal from the safety logic, the electromagnet holding the DSR is de-energised. Hence the DSR is released into the active core and at the end of travel DSR gets deposited in its bottom position. Because of the mechanical constraints, hard wired connectivity is not permitted from the DSR subassembly to the instrumentation outside the reactor. Hence an inductively coupled Eddy Current Position Sensor (ECPS) has been conceptualized to detect that the DSR has reached its bottom most position and to measure the drop time. Results of feasibility study on laboratory model have been reported earlier. Testing of a 1:1 scale engineering model of ECPS is reported in this paper. Results obtained from the high temperature sodium testing of ECPS indicate a clearly measurable change in pick up voltage with sensitivity of 11 % at 675 Hz. The ECPS is in advanced stage of implementation in DSRDM of PFBR. (authors)

  7. Plasma surface kinetics studies of silicon dioxide etch process in inductively coupled fluorocarbon plasmas

    NASA Astrophysics Data System (ADS)

    Chang, Won-Seok; Yu, Dong-Hun; Cho, Deog-Gyun; Yook, Yeong-Geun; Chun, Poo-Reum; Lee, Se-Ah; Kwon, Deuk-Chul; Im, Yeon-Ho

    2013-09-01

    With continuous decrease of nanoscale design rule, plasma etching processes to form high aspect ratio contact hole still remains a challenge to overcome their inherent drawbacks such as bowing and twisted feature. Due to their complexities there still exist big gaps between current research status and predictable modeling of this process. To address this issue, we proposed a surface kinetic model of silicon nitride etch process under inductively coupled fluorocarbon plasmas. For this work, the cut-off probe and quadrapole mass spectroscopy were used for measuring electrical plasma properties, the ion and neutral radical species. Furthermore, the systematic surface analysis was performed to investigate the thickness and chemical bonding of polymer passivation layer during the etch process. The proposed semi-global surface kinetic model can consider deposition of polymer passivation layer and silicon nitride etching self-consistently. The predicted modeling results showed good agreement with experimental data. We believe that our research will provide valuable information to avoid the empirical development of plasma etching process.

  8. Investigations of the use of inductively coupled plasma emissions for chemical analysis

    NASA Astrophysics Data System (ADS)

    Heine, D. R.

    Investigations of applications of the inductively coupled plasma (ICP) for analytical atomic emission spectroscopy are performed. Emissions below 185 nm, analysis of wear metals in lubricating oils, and use of the ICP as a selective detector for high performance liquid chromatography (HPLC) are studied. A unique plasma coolant tube containing a side arm which allows direct observation of the discharge is used to investigate emissions in the vacuum ultraviolet spectral region between 120 and 185 nm. Emission from elements which do not emit radiation in the visible region are observed. A heated sample introduction system attached to a Babington nebulizer is investigated as a means to aerosolize lubricating oils for introduction into the ICP. This allows direct analysis of wear metals in oil samples without requiring the usual sample dilutions. The ICP is used as a selective detector for HPLC. Nucleotides separated by anion exchange chromatography are determined in the ICP by observing phosphorous emissions. Methanol and acetonitrile used for reverse phase HPLC are successfully run in the IPC.

  9. Neutral Gas Temperature Estimates in an Inductively Coupled CF4 Plasma by Fitting Diatomic Emission Spectra

    NASA Technical Reports Server (NTRS)

    Cruden, Brett A.; Rao, M. V. V. S.; Sharma, Surendra P.; Meyyappan, M.

    2001-01-01

    This work examines the accuracy of plasma neutral temperature estimates by fitting the rotational band envelope of different diatomic species in emission. Experiments are performed in an inductively coupled CF4 plasma generated in a Gaseous Electronics Conference reference cell. Visible and ultraviolet emission spectra are collected at a power of 300 W (approximately 0.7 W/cc) and pressure of 30 mtorr. The emission bands of several molecules (CF, CN, C2, CO, and SiF) are fit simultaneously for rotational and vibrational temperatures and compared. Four different rotational temperatures are obtained: 1250 K for CF and CN, 1600 K for CO, 1800 K for C2, and 2300 K for SiF. The vibrational temperatures obtained vary from 1750-5950 K, with the higher vibrational temperatures generally corresponding to the lower rotational temperatures. These results suggest that the different species have achieved different degrees of equilibration between the rotational and vibrational modes and may not be equilibrated with the translational temperatures. The different temperatures are also related to the likelihood that the species are produced by ion bombardment of the surface, with etch products like SiF, CO, and C2 having higher temperatures than species expected to have formed in the gas phase.

  10. Etch Process Sensitivity To An Inductively Coupled Plasma Etcher Treated With Fluorine-Based Plasma

    NASA Astrophysics Data System (ADS)

    Xu, Songlin; Sun, Zhiwen; Qian, Xueyu; Yin, Gerald

    1997-10-01

    Significant etch rate drop after the treatment of an etch chamber with Fluorine-based plasma has been found for some silicon etch processes on an inductively coupled plasma reactor, which might cause problems in IC production line once the etch chamber runs alternative processes with F-based and F-free chemistry, or needs frequent cleaning with F-plasma. In this work, a systematic study of the root cause of process sensitivity to the etch chamber treated with F-plasma has been conducted. The experimental results show that pressure is a key factor to affect the etch rate drop. Processes at high pressure are more sensitive than those at low pressure because the quenching of neutral reactive species becomes more severe after the F-treatment. O2 addition also increases the etch rate sensitivity, basically due to higher O2(subscript: )concentration after F-treatment which enhances the oxidation of silicon. The EDX and XPS elemental analysis of the chamber interior wall reveals a significant composition change after the interaction with F-plasma, the altered surface might accelerate the recombination of free radical species.

  11. Laser ablation inductively coupled plasma mass spectrometry imaging of metals in experimental and clinical Wilson's disease

    PubMed Central

    Boaru, Sorina Georgiana; Merle, Uta; Uerlings, Ricarda; Zimmermann, Astrid; Flechtenmacher, Christa; Willheim, Claudia; Eder, Elisabeth; Ferenci, Peter; Stremmel, Wolfgang; Weiskirchen, Ralf

    2015-01-01

    Wilson's disease is an autosomal recessive disorder in which the liver does not properly release copper into bile, resulting in prominent copper accumulation in various tissues. Affected patients suffer from hepatic disorders and severe neurological defects. Experimental studies in mutant mice in which the copper-transporting ATPase gene (Atp7b) is disrupted revealed a drastic, time-dependent accumulation of hepatic copper that is accompanied by formation of regenerative nodes resembling cirrhosis. Therefore, these mice represent an excellent exploratory model for Wilson's disease. However, the precise time course in hepatic copper accumulation and its impact on other trace metals within the liver is yet poorly understood. We have recently established novel laser ablation inductively coupled plasma mass spectrometry protocols allowing quantitative metal imaging in human and murine liver tissue with high sensitivity, spatial resolution, specificity and quantification ability. By use of these techniques, we here aimed to comparatively analyse hepatic metal content in wild-type and Atp7b deficient mice during ageing. We demonstrate that the age-dependent accumulation of hepatic copper is strictly associated with a simultaneous increase in iron and zinc, while the intrahepatic concentration and distribution of other metals or metalloids is not affected. The same findings were obtained in well-defined human liver samples that were obtained from patients suffering from Wilson's disease. We conclude that in Wilson's disease the imbalances of hepatic copper during ageing are closely correlated with alterations in intrahepatic iron and zinc content. PMID:25704483

  12. Elemental Bioimaging by Means of Fast Scanning Laser Ablation-Inductively Coupled Plasma-Mass Spectrometry.

    PubMed

    Wehe, Christoph A; Thyssen, Georgina M; Herdering, Christina; Raj, Indra; Ciarimboli, Giuliano; Sperling, Michael; Karst, Uwe

    2015-08-01

    One of the most common setups for elemental bioimaging, the hyphenation of a laser ablation (LA) system and an inductively coupled plasma mass spectrometer (ICP-MS), was expanded by adding full scan mass spectrometric information as another dimension of information. While most studies deal with the analysis of typically not more than up to 10 isotopes per scan cycle, a fast scanning quadrupole mass analyzer was utilized to record the full mass spectrum of interest in this work. Mass-to-charge ratios from 6 to 250 were observed within one cycle. Besides the x- and y-position on the ablated sample and the intensity, the m/z-ratio served as fourth variable for each pixel of the obtained data, closing thereby the gap between "inorganic" and "organic" mass spectrometric imaging techniques. The benefits of this approach include an improved control of interferences, the discovery of unexpected elemental distributions, the possibility to plot isotopic ratios, and to integrate the intensities of a certain number of mass channels recorded for each isotope, thus virtually increasing sensitivity. The respective data are presented for dried droplets as well as embedded animal and human tissue slices. Limits of detection were calculated and found to be in accordance with counting statistics. A dedicated software macro was developed for data manipulation prior to common evaluation and image creation. PMID:25947196

  13. Virus Multiplicity of Infection Affects Type I Interferon Subtype Induction Profiles and Interferon-Stimulated Genes

    PubMed Central

    Zaritsky, Luna A.; Bedsaul, Jacquelyn R.

    2015-01-01

    ABSTRACT Type I interferons (IFNs) are induced upon viral infection and important mediators of innate immunity. While there is 1 beta interferon (IFN-β) protein, there are 12 different IFN-α subtypes. It has been reported extensively that different viruses induce distinct patterns of IFN subtypes, but it has not been previously shown how the viral multiplicity of infection (MOI) can affect IFN induction. In this study, we discovered the novel finding that human U937 cells infected with 2 different concentrations of Sendai virus (SeV) induce 2 distinct type I IFN subtype profiles. Cells infected at the lower MOI induced more subtypes than cells infected at the higher MOI. We found that this was due to the extent of signaling through the IFN receptor (IFNAR). The cells infected at the lower viral MOI induced the IFNAR2-dependent IFN-α subtypes 4, 6, 7, 10, and 17, which were not induced in cells infected at higher virus concentrations. IFN-β and IFN-α1, -2, and -8 were induced in an IFNAR-independent manner in cells infected at both virus concentrations. IFN-α5, -14, -16, and -21 were induced in an IFNAR-dependent manner in cells infected at lower virus concentrations and in an IFNAR-independent manner in cells infected at higher virus concentrations. These differences in IFN subtype profiles in the 2 virus concentrations also resulted in distinct interferon-stimulated gene induction. These results present the novel finding that different viral MOIs differentially activate JAK/STAT signaling through the IFNAR, which greatly affects the profile of IFN subtypes that are induced. IMPORTANCE Type I IFNs are pleiotropic cytokines that are instrumental in combating viral diseases. Understanding how the individual subtypes are induced is important in developing strategies to block viral replication. Many studies have reported that different viruses induce distinct type I IFN subtype profiles due to differences in the way viruses are sensed in different cell types

  14. In Vitro multiple shoot induction and plant regeneraton from shoot apex of Hibiscus actosella Welw. ex. Hiern

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Multiple shoot induction and plant regeneration was achieved from shoot apices in two Hibiscus acetosella Welw. ex. Hiern variants by using the growth regulators thidiazuron (N-phenyl-N’-1,2,3-thidazol-5-ylurea, TDZ) and 6-benzyladenine (BA) and growing shoot apices for 30 days in 21 different media...

  15. Complex image method for RF antenna-plasma inductive coupling calculation in planar geometry. Part II: measurements on a resonant network

    NASA Astrophysics Data System (ADS)

    Guittienne, Ph; Jacquier, R.; Howling, A. A.; Furno, I.

    2015-12-01

    Measurements and analysis of a radio-frequency planar antenna are presented for applications in inductively-coupled plasma processing. The network of inductive and capacitive elements exhibits high currents under resonance which are efficient for plasma generation. Mode frequencies and impedances are accurately calculated by accounting for the mutual partial inductances using the impedance matrix. The effect of plasma inductive coupling on mode frequency shift and mode impedance is estimated using the complex image method, giving good agreement with experiment. It is proposed that the complex image method combined with the partial inductance concept (see the accompanying paper, Part I (Howling et al 2015 Plasma Sources Sci. Technol. 24 065014)) offers a general way to calculate the impedance characteristics of inductively-coupled plasma sources in planar geometry.

  16. Observation of helicon wave with m = 0 antenna in a weakly magnetized inductively coupled plasma source

    NASA Astrophysics Data System (ADS)

    Ellingboe, Bert; Sirse, Nishant; Moloney, Rachel; McCarthy, John

    2015-09-01

    Bounded whistler wave, called ``helicon wave,'' is known to produce high-density plasmas and has been exploited as a high density plasma source for many applications, including electric propulsion for spacecraft. In a helicon plasma source, an antenna wrapped around the magnetized plasma column launches a low frequency wave, ωce/2 >ωhelicon >ωce/100, in the plasma which is responsible for maintaining high density plasma. Several antenna designs have been proposed in order to match efficiently the wave modes. In our experiment, helicon wave mode is observed using an m = 0 antenna. A floating B dot probe, compensated to the capacitively coupled E field, is employed to measure axial-wave-field-profiles (z, r, and θ components) in the plasma at multiple radial positions as a function of rf power and pressure. The Bθ component of the rf-field is observed to be unaffected as the wave propagates in the axial direction. Power coupling between the antenna and the plasma column is identified and agrees with the E, H, and wave coupling regimes previously seen in M =1 antenna systems. That is, the Bz component of the rf-field is observed at low plasma density as the Bz component from the antenna penetrates the plasma. The Bz component becomes very small at medium density due to shielding at the centre of the plasma column; however, with increasing density, a sudden ``jump'' occurs in the Bz component above which a standing wave under the antenna with a propagating wave away from the antenna are observed.

  17. Ready or not: planning for health declines in couples with advanced multiple sclerosis.

    PubMed

    Chen, Hannah; Habermann, Barbara

    2013-02-01

    This study explored how couples living with advanced multiple sclerosis approach planning for health changes together. A qualitative descriptive approach was used, with multiple in-depth interviews. Ten couples were interviewed, consisting of 10 participants with advanced multiple sclerosis and their 10 respective spouses. Interviews were transcribed verbatim and analyzed for themes related to dyad decision making. Particular focus was paid to how or if couples planned for worsening health, including advance care planning. Characteristics of couples who had made plans for worsening health included a desire to make decisions ahead of time, work in a healthcare field, and a life-threatening health event for the care-giving partner. Characteristics of couples who had not discussed plans for worsening health included diminished quality of communication between partners and hoping for a cure. Findings suggest that providers may need to assess quality of communication between partners, because strained communication may negatively affect the process of informed healthcare decision making. PMID:23291870

  18. GWAS analysis implicates NF-κB-mediated induction of inflammatory T cells in multiple sclerosis.

    PubMed

    Hussman, J P; Beecham, A H; Schmidt, M; Martin, E R; McCauley, J L; Vance, J M; Haines, J L; Pericak-Vance, M A

    2016-07-01

    To identify genes and biologically relevant pathways associated with risk to develop multiple sclerosis (MS), the Genome-Wide Association Studies noise reduction method (GWAS-NR) was applied to MS genotyping data. Regions of association were defined based on the significance of linkage disequilibrium blocks. Candidate genes were cross-referenced based on a review of current literature, with attention to molecular function and directly interacting proteins. Supplementary annotations and pathway enrichment scores were generated using The Database for Annotation, Visualization and Integrated Discovery. The candidate set of 220 MS susceptibility genes prioritized by GWAS-NR was highly enriched with genes involved in biological pathways related to positive regulation of cell, lymphocyte and leukocyte activation (P=6.1E-15, 1.2E-14 and 5.0E-14, respectively). Novel gene candidates include key regulators of NF-κB signaling and CD4+ T helper type 1 (Th1) and T helper type 17 (Th17) lineages. A large subset of MS candidate genes prioritized by GWAS-NR were found to interact in a tractable pathway regulating the NF-κB-mediated induction and infiltration of pro-inflammatory Th1/Th17 T-cell lineages, and maintenance of immune tolerance by T-regulatory cells. This mechanism provides a biological context that potentially links clinical observations in MS to the underlying genetic landscape that may confer susceptibility. PMID:27278126

  19. GWAS analysis implicates NF-κB-mediated induction of inflammatory T cells in multiple sclerosis

    PubMed Central

    Hussman, J P; Beecham, A H; Schmidt, M; Martin, E R; McCauley, J L; Vance, J M; Haines, J L; Pericak-Vance, M A

    2016-01-01

    To identify genes and biologically relevant pathways associated with risk to develop multiple sclerosis (MS), the Genome-Wide Association Studies noise reduction method (GWAS-NR) was applied to MS genotyping data. Regions of association were defined based on the significance of linkage disequilibrium blocks. Candidate genes were cross-referenced based on a review of current literature, with attention to molecular function and directly interacting proteins. Supplementary annotations and pathway enrichment scores were generated using The Database for Annotation, Visualization and Integrated Discovery. The candidate set of 220 MS susceptibility genes prioritized by GWAS-NR was highly enriched with genes involved in biological pathways related to positive regulation of cell, lymphocyte and leukocyte activation (P=6.1E-15, 1.2E-14 and 5.0E-14, respectively). Novel gene candidates include key regulators of NF-κB signaling and CD4+ T helper type 1 (Th1) and T helper type 17 (Th17) lineages. A large subset of MS candidate genes prioritized by GWAS-NR were found to interact in a tractable pathway regulating the NF-κB-mediated induction and infiltration of pro-inflammatory Th1/Th17 T-cell lineages, and maintenance of immune tolerance by T-regulatory cells. This mechanism provides a biological context that potentially links clinical observations in MS to the underlying genetic landscape that may confer susceptibility. PMID:27278126

  20. The utility of respiratory inductance plethysmography in REM sleep scoring during multiple sleep latency testing.

    PubMed

    Drakatos, Panagis; Higgins, Sean; Duncan, Iain; Bridle, Kate; Briscoe, Sam; Leschziner, Guy D; Kent, Brian D; Williams, Adrian J

    2016-08-01

    Rapid eye movement sleep (REM) presents with a characteristic erratic breathing pattern. We investigated the feasibility of using respiration, derived from respiratory inductance plethysmography (RIP), in conjunction with chin electromyography, electrocardiography and pulse oximetry to facilitate the identification of REM sleep (RespREM) during nocturnal polysomnography (NPSG) and Multiple Sleep Latency Testing (MSLT). The Cohen's weighted kappa for the presence of REM and its duration in 20 consecutive NPSGs, using RespREM and compared to the current guidelines, ranged between 0.74-0.93 and 0.68-0.73 respectively for 5 scorers. The respective intraclass correlation coefficients were above 0.89. In 97.7% of the Sleep-Onset-REM-Periods (SOREMPs) during 41 consecutive MSLTs with preserved RIP, the RespREM was present and in 46.6% it coincided with the REM onset, while in the majority of the remainder RespREM preceded conventional REM onset. The erratic breathing pattern during REM, derived from RIP, is present and easily recognisable during SOREMPs in the MSLTs and may serve as a useful adjunctive measurement in identifying REM sleep. PMID:27141851

  1. Quantitative determination of mass-resolved ion densities in H{sub 2}-Ar inductively coupled radio frequency plasmas

    SciTech Connect

    Sode, M.; Schwarz-Selinger, T.; Jacob, W.

    2013-03-07

    Inductively coupled H{sub 2}-Ar plasmas are characterized by an energy-dispersive mass spectrometer (plasma monitor), a retarding field analyzer, optical emission spectroscopy, and a Langmuir probe. A procedure is presented that allows determining quantitatively the absolute ion densities of Ar{sup +}, H{sup +}, H{sub 2}{sup +}, H{sub 3}{sup +}, and ArH{sup +} from the plasma monitor raw signals. The calibration procedure considers the energy and mass-dependent transmission of the plasma monitor. It is shown that an additional diagnostic like a Langmuir probe or a retarding field analyzer is necessary to derive absolute fluxes with the plasma monitor. The conversion from fluxes into densities is based on a sheath and density profile model. Measurements were conducted for a total gas pressure of 1.0 Pa. For pure H{sub 2} plasmas, the dominant ion is H{sub 3}{sup +}. For mixed H{sub 2}-Ar plasmas, the ArH{sup +} molecular ion is the most dominant ion species in a wide parameter range. The electron density, n{sub e}, is around 3 Multiplication-Sign 10{sup 16} m{sup -3} and the electron temperature, T{sub e}, decreases from 5 to 3 eV with increasing Ar content. The dissociation degree was measured by actinometry. It is around 1.7% nearly independent on Ar content. The gas temperature, estimated by the rotational distribution of the Q-branch lines of the H{sub 2} Fulcher-{alpha} diagonal band (v Prime =v Double-Prime =2) is estimated to (540 {+-} 50) K.

  2. Bulk vertical micromachining of single-crystal sapphire using inductively coupled plasma etching for x-ray resonant cavities

    NASA Astrophysics Data System (ADS)

    Chen, P.-C.; Lin, P.-T.; Mikolas, D. G.; Tsai, Y.-W.; Wang, Y.-L.; Fu, C.-C.; Chang, S.-L.

    2015-01-01

    To provide coherent x-ray sources for probing the dynamic structures of solid or liquid biological substances on the picosecond timescale, a high-aspect-ratio x-ray resonator cavity etched from a single crystal substrate with a nearly vertical sidewall structure is required. Although high-aspect-ratio resonator cavities have been produced in silicon, they suffer from unwanted multiple beam effects. However, this problem can be avoided by using the reduced symmetry of single-crystal sapphire in which x-ray cavities may produce a highly monochromatic transmitted x-ray beam. In this study, we performed nominal 100 µm deep etching and vertical sidewall profiles in single crystal sapphire using inductively coupled plasma (ICP) etching. The large depth is required to intercept a useful fraction of a stopped-down x-ray beam, as well as for beam clearance. An electroplated Ni hard mask was patterned using KMPR 1050 photoresist and contact lithography. The quality and performance of the x-ray cavity depended upon the uniformity of the cavity gap and therefore verticality of the fabricated vertical sidewall. To our knowledge, this is the first report of such deep, vertical etching of single-crystal sapphire. A gas mixture of Cl2/BCl3/Ar was used to etch the sapphire with process variables including BCl3 flow ratio and bias power. By etching for 540 min under optimal conditions, we obtained an x-ray resonant cavity with a depth of 95 µm, width of ~30 µm, gap of ~115 µm and sidewall profile internal angle of 89.5°. The results show that the etching parameters affected the quality of the vertical sidewall, which is essential for good x-ray resonant cavities.

  3. Homogeneous and Heterogeneous Reaction Mechanisms in CH3F-O2 Inductively Coupled Plasmas

    NASA Astrophysics Data System (ADS)

    Donnelly, Vincent M.; Karakas, Erdinc; Kaler, Sanbir; Lou, Qiaowei; Economou, Demetre J.

    2013-09-01

    CH3F/O2 containing plasmas are used in selective Si3N4 etching over Si or SiO2. Fundamental plasma studies in these gas mixtures are scarce. In this work, optical emission rare gas actinometry and a global chemistry model were employed to study inductively couple plasmas in CH3F/O2 gas mixtures. For constant CH3F and O2 flow rates, the absolute H, F and O atom densities increased linearly with power. The feedstock gas was highly dissociated and most of the fluorine and oxygen was contained in reaction products HF, CO, CO2, H2O and OH. Measured number densities as a function of O2 addition to CH3F/O2 changed abruptly for H, O, and particularly F atoms (factor of 4) at 48% O2 A corresponding transition was also observed in electron density, electron temperature and gas temperature, as well as in C, CF and CH optical emission. These abrupt transitions were attributed to the reactor wall reactivity, changing from a polymer-coated surface to a polymer-free surface, and vice-versa, as the O2 content in the feed gas crossed 48%. Homogeneous chemistry dominates above 48% O2; a kinetic model with no adjustable parameters is in excellent agreement with the absolute F and H and relative HF number density dependence on power and pressure. CH3F/O2 containing plasmas are used in selective Si3N4 etching over Si or SiO2. Fundamental plasma studies in these gas mixtures are scarce. In this work, optical emission rare gas actinometry and a global chemistry model were employed to study inductively couple plasmas in CH3F/O2 gas mixtures. For constant CH3F and O2 flow rates, the absolute H, F and O atom densities increased linearly with power. The feedstock gas was highly dissociated and most of the fluorine and oxygen was contained in reaction products HF, CO, CO2, H2O and OH. Measured number densities as a function of O2 addition to CH3F/O2 changed abruptly for H, O, and particularly F atoms (factor of 4) at 48% O2 A corresponding transition was also observed in electron density

  4. A study of the relation between the limit of detection and the limit of quantitation in inductively coupled plasma spectrochemistry

    NASA Astrophysics Data System (ADS)

    Carré, M.; Excoffier, S.; Mermet, J. M.

    1997-12-01

    The limit of quantitation based on a repeatability threshold concept is compared with the limit of detection in induction coupled plasma atomic emission spectrometry (ICP-AES) and induction coupled plasma mass spectrometry (ICP-MS). A 5%-based limit of quantitation would normally correspond to 10 times the 3-σ based limit of detection. However, because of a possible lack of linearity of the calibration graph at low concentrations, some additional noise not taken into consideration and the possible use of time-correlated multichannel detection, this ratio of 10 cannot be used in every case. It is suggested that a suitable way of determining the limit of quantitation is to establish the plot of the percentage relative standard deviation (RSD) of the net signal as a function of the concentration in a range from the limit of detection to 50 times this limit.

  5. Fractionation analysis of manganese in Turkish hazelnuts (Corylus avellana L.) by inductively coupled plasma-mass spectrometry.

    PubMed

    Erdemir, Umran Seven; Gucer, Seref

    2014-11-01

    In this study, an analytical fractionation scheme based on water, diethyl ether, n-hexane, and methanol extractions has been developed to identify manganese-bound fractions. Additionally, in vitro simulated gastric and intestinal digestion, n-octanol extraction, and activated carbon adsorption were used to interpret the manganese-bound structures in hazelnuts in terms of bioaccessibility. The total content of manganese in the samples was determined by inductively coupled plasma-mass spectrometry after microwave-assisted digestion, and additional validation was performed using atomic absorption spectroscopy. Water fractions were further evaluated by high-performance liquid chromatography hyphenated to inductively coupled plasma-mass spectrometry for the identification of water-soluble manganese fractions in hazelnut samples. The limits of detection and quantification were 3.6 and 12.0 μg L(-1), respectively, based on peak height. PMID:25310841

  6. Determination of arsenic in gold by flow injection inductively coupled plasma mass spectrometry with matrix removal by reductive precipitation

    NASA Astrophysics Data System (ADS)

    Becotte-Haigh, Paul; Tyson, Julian F.; Denoyer, Eric; Hinds, Michael W.

    1996-12-01

    Arsenic was determined in gold by flow injection hydride generation inductively coupled plasma-mass spectrometry following a batch mode reductive precipitation removal of the interfering gold matrix. A solution of potassium iodide, L-ascorbic acid, and hydrochloric acid was used as the reluctant. The recovery of gold by precipitation and filtration was 99 ± 3%. The detection limit for arsenic in gold was 55 ng g -1 in the solid. The concentration of arsenic that was determined in the Royal Canadian Mint gold sample FAU-10 was 29.7 μg g -1 in the solid; this value was indistinguishable, with 95% confidence, from values determined at the Royal Canadian Mint by graphite furnace atomic absorption spectrometry and by inductively coupled plasma-mass spectrometry. The standard deviation for four replicate determinations of the arsenic in FAU-10 was 0.972 μg g -1 in the solid.

  7. Comparison of various interpretation methods of the electric probe measurements in inductively coupled Ar and O{sub 2} plasmas

    SciTech Connect

    Woo Seo, Min; Keun Bae, Min; Chung, T. H.

    2014-02-15

    In low-pressure inductively coupled argon and oxygen discharges, the plasma density and electron temperature and the electron energy distribution function (EEDF) were obtained by using a cylindrical electric probe. The plasma densities were determined by various methods to interpret the probe current-voltage characteristic curve: the EEDF integration, the electron saturation current, the ion current at the floating potential, and the orbital-motion-limited (OML) ion current. Quite a good agreement exists between the plasma densities determined by various classical methods. Although the probe technique has some limitation in electronegative plasmas, the plasma densities determined from OML theory compare well with those measured by the ion saturation current at the floating potential in the oxygen discharges. In addition, the EEDFs of inductively coupled Ar and oxygen plasmas are observed to be nearly Maxwellian at the pressure range of 1-40 mTorr.

  8. Documenting utility of paddlefish otoliths for quantification of metals using inductively coupled plasma mass spectrometry

    USGS Publications Warehouse

    Long, James M.; Schaffler, James J.

    2013-01-01

    RATIONALE The otoliths of the inner ear of fishes record the environment of their surrounding water throughout their life. For paddlefish (Polyodon spathula), otoliths have not been routinely used by scientists since their detriments were outlined in the early 1940s. We sought to determine if paddlefish otoliths were useful for resolving elemental information contained within. METHODS Adult paddlefish were collected from two wild, self-sustaining populations in Oklahoma reservoirs in the Arkansas River basin. Juveniles were obtained from a hatchery in the Red River basin of Oklahoma. Otoliths were removed and laser ablation, inductively coupled plasma mass spectrometry (ICP-MS) was used to quantify eight elements (Li, Mg, Mn, Rb, Sr, Y, Ba, and Pb) along the core and edge portions, which were analyzed for differences between otolith regions and among paddlefish sources. RESULTS Differences were found among samples for six of the eight elements examined. Otoliths from Red River basin paddlefish born in a hatchery had significantly lower amounts of Mg and Mn, but higher levels of Rb than otoliths from wild paddlefish in the Arkansas River basin. Concentrations of Y, Sr, and Ba were reduced on the edges of adult paddlefish from both reservoirs compared with the cores. CONCLUSIONS This research shows the utility of using an ICP-MS analysis of paddlefish otoliths. Future research that seeks to determine sources of paddlefish production, such as which reservoir tributaries are most important for reproduction or what proportion of the population is composed of wild versus hatchery-produced individuals, appears promising. Published in 2013. This article is a U.S. Government work and is in the public domain in the USA.

  9. Determination of elemental impurities in poly(vinyl chloride) by inductively coupled plasma optical emission spectrometry.

    PubMed

    Pereira, Leticia S F; Pedrotti, Matheus F; Miceli, Tatiane M; Pereira, Juliana S F; Flores, Erico M M

    2016-05-15

    In this work, a method for poly(vinyl chloride) (PVC) analysis by inductively coupled plasma optical emission spectrometry (ICP-OES) was developed. Samples were digested by microwave-induced combustion (MIC) and thirteen elements (Ba, Cd, Co, Cu, Fe, Mg, Mn, Mo, Ni, Pb, Sr, V and Zn) were determined by ICP-OES. Operational conditions of MIC were investigated allowing quantitative determination of all the analytes and suitable results were achieved using a 3 mol L(-1) HNO3 solution. Microwave-assisted wet digestion (MAWD) using closed quartz vessels and a single reaction chamber microwave digestion system (MAWD-SRC), were also evaluated for PVC digestion for results comparison. All the evaluated sample preparation methods were considered suitable for PVC digestion but MIC was preferable due to the possibility of using diluted HNO3 instead of concentrated reagents and due to the better digestion efficiency. The residual carbon content (RCC) in digests obtained by MIC was significantly lower in comparison with the values obtained after MAWD and by MAWD-SRC. Accuracy for the proposed method was better than 94% for all analytes by comparison of results with those obtained by neutron activation analysis (NAA). Using MIC, it was possible to digest a relatively high sample mass (500 mg) and up to 8 samples in less time (25 min) in comparison with MAWD and MAWD-SRC (about 60 min for both methods). The efficiency of digestion by MIC was higher 99% and lower limits of detection (as low as 0.1 µg g(-1)) were obtained avoiding the use of concentrated acids that is of great concern according to the current green chemistry recommendations. PMID:26992533

  10. Determination of 28 selected elements in textiles by axially viewed inductively coupled plasma optical emission spectrometry.

    PubMed

    Rezić, Iva; Zeiner, Michaela; Steffan, Ilse

    2011-01-15

    A simple, robust and reliable analytical procedure for the determination of 28 selected elements, namely Al, As, Ba, Be, Bi, Ca, Cd, Co, Cr, Cu, Fe, K, Hg, Mg, Mn, Mo, Na, Ni, Pb, Sc, Si, Se, Sn, Sm, Sr, Tl, V, and Zn in textile materials by inductively coupled plasma optical emission spectrometry (ICP-OES) after microwave digestion of samples was optimized and validated in this work. The total amount of elements present in textile samples was determined after microwave digestion of materials in 7 mol/L nitric acid within the optimal working program: 5 min at 150°C (power 250 W), 15 min 180°C (300 W) and 20 min at the maximum temperature of 200°C (350 W). For the quality control reasons, which were ascertained by analysis of the certified cotton trace elements reference material IAEA-V9, the ICP-OES method was optimized through several parameters: by comparing Meinhard and Gemcone Low Flow nebulizers efficiency, ranging nebulizer gas flows from 0.6 to 1.0 L/min, ranging sample flows from 0.8 to 1.2 mL/min, testing RF power from 1200 to 1400 W, detecting data acquisition time (read time) from 0 to 527 s, ranging washing (delay) time from 0 to 408 s, as well as by checking the occurring interferences for the optimal line selection. Validation included determination of linearity, selectivity, accuracy, reproducibility, precision and limits of detection calculated for all 28 selected elements of interest. The developed analytical procedure was successfully applied on textile fibers (cotton, flax and hemp) as well as on standard knitted textile sample materials (cotton and wool). PMID:21147330

  11. Slurry sampling electrothermal vaporization inductively coupled plasma mass spectrometry for steelmaking flue dust analysis

    NASA Astrophysics Data System (ADS)

    Coedo, A. G.; Dorado, T.; Padilla, I.; Maibusch, R.; Kuss, H.-M.

    2000-02-01

    A commercial atomic absorption graphite furnace (AAGF), with a self-made adapter and valve system, was used as a slurry sampling cell for electrothermal vaporization inductively coupled plasma mass spectrometry (ETV-ICP-MS). The system was applied to the determination of As, Sn, Sb, Se, Te, Bi, Cd, V, Ti and Mo in steelmaking flue dusts. Experimental conditions with respect to ETV and ICP-MS operating parameters were optimized. Compared to aqueous solutions, slurry samples were found to present better analyte transport. Microgram amounts of Rh were used to reduce the difference in analyte response in sensitivity for aqueous solutions of the tested analytes. No such increasing effect was observed for slurry samples and aqueous standards. An added quantity of Rh acting as modifier/carrier resulted in an increase for the same analytes in matrix-slurry solutions, even the addition of an extra Rh quantity has resulted in a decrease in the signals. The effect of Triton X-100 (used as a dispersant agent) on analyte intensity and precision was also studied. External calibration from aqueous standards spiked with 100 μg ml -1 Rh was performed to quantified 0.010 g/100 ml slurry samples. Results are presented for a certified reference electrical arc furnace flue dust (EAF): CRM-876-1 (Bureau of Analysis Samples Ltd., Cleveland, UK), a reference sample of coke ashes X-3705 (from AG der Dillinger Hüttenwerke, Germany), and a representative sample of EAF flue dust from a Spanish steelmaking company (CENIM-1). For the two reference materials an acceptable agreement with certificate values was achieved, and the results for the CENIM sample matched with those obtained from conventional nebulization solution.

  12. Investigation of magnetic-pole-enhanced inductively coupled nitrogen-argon plasmas

    NASA Astrophysics Data System (ADS)

    Jan, F.; Khan, A. W.; Saeed, A.; Zakaullah, M.

    2012-09-01

    This article presented the features of the mixed mode and H mode in magnetic pole enhanced, inductively coupled Ar-N2 plasmas using RF-compensated Langmuir probe measurements. To fully characterize plasma parameters and electron energy probability functions (EEPFs), the gas pressure and argon content were varied. It was observed that with increasing the nitrogen content and gas pressure, the critical RF power to sustain H mode increases; this increase was more prominent for pure nitrogen discharge at higher pressure. The electron number density (ne) shows increasing trend with increasing RF power, while at higher gas pressures, the electron number density decreases at fixed RF power. Mostly, the EEPFs show a Maxwellian distribution even at low RF power (for higher argon content in the discharge) and at moderate RF power (for higher or pure nitrogen content in the discharge) for pressures of 15-60 mTorr. With increasing the nitrogen content in the mixture, the low energy part of the EEPF is more Druyvesteyn with a distorted high energy tail at low RF power. At fixed RF power, the slope of EEPF changes sharply with increasing pressure. It was observed that in hybrid mode, the EEPF at higher gas pressure (75 mTorr) in a pure nitrogen discharge shows a flat hole near the average electron energy of 3 eV and changes to Maxwellian distribution in H mode. The skin depth versus RF power shows that the skin depth is smaller than the critical dimension of the chamber, regardless of the gas type and the gas pressure.

  13. Photochemical vapor generation of lead for inductively coupled plasma mass spectrometric detection

    NASA Astrophysics Data System (ADS)

    Duan, Hualing; Zhang, Ningning; Gong, Zhenbin; Li, Weifeng; Hang, Wei

    2016-06-01

    Photochemical vapor generation (PCVG) of lead was successfully achieved with a simplified and convenient system, in which only low molecular weight organic acid and a high-efficiency photochemical reactor were needed. The reactor was used to generate lead volatile species when a solution of lead containing a small amount of low molecular weight organic acid was pumped through. Several factors, including the concentration of acetic acid, the concentration of hydrochloride acid, and the irradiation time of UV light were optimized. Under the optimal conditions, including the addition of 0.90% (v/v) acetic acid and 0.03% (v/v) hydrochloride acid, and irradiation time of 28 s, intense and repeatable signal of lead volatile species was successfully obtained and identified with inductively coupled plasma mass spectrometry (ICPMS). In addition, the effects from inorganic anions and transition metal ions, including Cl-, NO3-, SO42 -, Cu2 +, Fe3 +, Co2 + and Ni2 +, were investigated, which suggests that their suppression to the PCVG of lead was in the order of Cl- < SO42 - < NO3- for anions and Ni2 +, Co2 + < Fe3 + < Cu2 + for transition metal ions. Under optimized conditions, relative standard derivation (RSD) of 4.4% was achieved from replicate measurements (n = 5) of a standard solution of 0.1 μg L- 1 lead. And, the limit of quantitation (LOQ, 10σ) of 0.012 μg L- 1 lead was obtained using this method and the method blank could be easily controlled down to 0.023 μg L- 1. To validate applicability of this method, it was also employed for the determination of lead in tap water, rain water and lake water.

  14. Multi-element analysis of compost by laser ablation-inductively coupled plasma mass spectrometry.

    PubMed

    Jiménez, María S; Gómez, María T; Castillo, Juan R

    2007-05-15

    Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) has been applied to multi-element determination in compost samples. Since compost is a heterogeneous mixture of organic and inorganic materials, the influence of sample heterogeneity on the accuracy and precision of analysis was investigated. Several parameters related to the following were studied: laser (energy, laser-beam diameter, preablation. rastering speed, carrier-gas flow rate), sample preparation (use of compacted pellets, grinding time, particle size, sample amount, length of hydraulic press treatment, position of line scan), and the ICP-MS system (quantitative versus semiquantitative analysis, matrix-matched standards and liquid standards calibration). The main causes of imprecision in sample preparation were determined to be particle size and grinding time. The effect of sample heterogeneity on precision was also evaluated by using different test samples (pellets). For Ni, Zn and Pb, the greatest contribution to the total relative standard deviation (R.S.D.) was related to analyte determination. For Mn and Cu, sample heterogeneity and analyte determination contributed equally to the total R.S.D., whereas for Cr, Co, Cd and Hg sample heterogeneity accounted for most of the total R.S.D. A comparison of semiquantitative and quantitative analysis modes showed that better precision and very good agreement with certified reference material was obtained with the latter, but semiquantitative analysis could be a practical alternative. Although accuracy of results was improved with matrix-matched standards calibration the use of standard addition calibration with aqueous standards could be another possibility. PMID:19071737

  15. Laser ablation inductively coupled plasma optical emission spectrometry for analysis of pellets of plant materials

    NASA Astrophysics Data System (ADS)

    Gomes, Marcos S.; Schenk, Emily R.; Santos, Dário; Krug, Francisco José; Almirall, José R.

    An evaluation of laser ablation inductively coupled plasma optical emission spectroscopy (LAICP OES) for the direct analysis of pelleted plant material is reported. Ground leaves of orange citrus, soy and sugarcane were comminuted using a high-speed ball mill, pressed into pellets and sampled directly with laser ablation and analyzed by ICP OES. The limits of detection (LODs) for the method ranged from as low as 0.1 mg kg- 1 for Zn to as high as 94 mg kg- 1 for K but were generally below 6 mg kg- 1 for most of the elements of interest. A certified reference material consisting of a similar matrix (NIST SRM 1547 peach leaves) was used to check the accuracy of the calibration and the reported method resulted in an average bias of ~ 5% for all the elements of interest. The precision for the reported method ranged from as low as 4% relative standard deviation (RSD) for Mn to as high as 17% RSD for Zn but averaged ~ 6.5% RSD for all the elements (n = 10). The proposed method was tested for the determination of Ca, Mg, P, K, Fe, Mn, Zn and B, and the results were in good agreement with those obtained for the corresponding acid digests by ICP-OES, no differences being observed by applying a paired t-test at the 95% confidence level. The reported direct solid sampling method provides a fast alternative to acid digestion that results in similar and appropriate analytical figures of merit with regard to sensitivity, accuracy and precision for plant material analysis.

  16. Acquisition of a High-resolution Inductively Coupled Plasma Mass Spectrometer for Cosmochemical and Geochemical Research

    NASA Technical Reports Server (NTRS)

    Lauretta, D. S.

    2004-01-01

    The primary goal of our research in this program is to develop new techniques for the analysis of volatile trace elements in very small samples using inductively coupled plasma mass spectrometry (ICP-MS) in preparation for samples returned by the Stardust mission. The instrument that will serve as the basis of our experiments is the ELEMENT2 high-resolution ICP-MS. We have spent the past year designing the laboratory to house this instrument as well as space to store and prepare samples returned by the Stardust mission. Unfortunately, the location that we had initially selected for the instrument turned out to be insufficient for our needs. This was determined almost eight months into the first year of our funding cycle, after extensive work including the production of engineering drawings. However, during this time the Lunar and Planetary Laboratory was selected to lead Phoenix, the first Mars Scout mission. As a result of this award LPL purchased a new, 50,000 square foot building. We have acquired 1400 square feet of laboratory space in this new facility. Four-hundred square feet will be used for a class-100 clean room. This area is designated for storage and preparation of extraterrestrial materials. The additional 1000 square feet will house the ELEMENT2 ICP-MS and peripheral devices. This is an enormous amount of space for this instrument, but it provides plenty of room for expansion in the future. The ICP-MS and the clean room facilities have been purchased. The instrument has been delivered. The startup time for this instrument is relatively short and we expect to be collecting our first data by mid-summer.

  17. Gunshot residue testing in suicides: Part II: Analysis by inductive coupled plasma-atomic emission spectrometry.

    PubMed

    Molina, D Kimberley; Castorena, Joe L; Martinez, Michael; Garcia, James; DiMaio, Vincent J M

    2007-09-01

    Several different methods can be employed to test for gunshot residue (GSR) on a decedent's hands, including scanning electron microscopy with energy dispersive x-ray (SEM/EDX) and inductive coupled plasma-atomic emission spectrometry (ICP-AES). In part I of this 2-part series, GSR results performed by SEM/EDX in undisputed cases of suicidal handgun wounds were studied. In part II, the same population was studied, deceased persons with undisputed suicidal handgun wounds, but GSR testing was performed using ICP-AES. A total of 102 cases were studied and analyzed for caliber of weapon, proximity of wound, and the results of the GSR testing. This study found that 50% of cases where the deceased was known to have fired a handgun immediately prior to death had positive GSR results by ICP/AES, which did not differ from the results of GSR testing by SEM/EDX. Since only 50% of cases where the person is known to have fired a weapon were positive for GSR by either method, this test should not be relied upon to determine whether someone has discharged a firearm and is not useful as a determining factor of whether or not a wound is self-inflicted or non-self-inflicted. While a positive GSR result may be of use, a negative result is not helpful in the medical examiner setting as a negative result indicates that either a person fired a weapon prior to death or a person did not fire a weapon prior to death. PMID:17721164

  18. Determination of Pu in urine at ultratrace level by sector field inductively coupled plasma mass spectrometry

    NASA Astrophysics Data System (ADS)

    Zoriy, M. V.; Pickhardt, C.; Ostapczuk, P.; Hille, R.; Becker, J. S.

    2004-04-01

    A new analytical procedure has been developed for the determination of Pu in urine at the low ag ml-1 concentration level by double-focusing sector field inductively coupled plasma mass spectrometry (ICP-SFMS). One liter of urine doped with 4 pg 242Pu was analyzed after co-precipitation with Ca3(PO4)2 followed by extraction chromatography on TEVA resin in order to enrich the Pu and remove uranium and matrix elements. Figures of merit of ICP-SFMS for the determination of Pu were studied using two nebulizers, PFA-100 and direct injection high-efficiency nebulizer (DIHEN), for solution introduction with uptake rates of 0.58 and 0.06 ml min-1, respectively. The sensitivity for Pu in ICP-SFMS was determined to be 2000 and 1380 MHz ppm-1 for the PFA-100 and DIHEN nebulizers, respectively. Due to the low solution uptake rate of DIHEN the absolute sensitivity was about seven times better and yielded 1380 counts fg-1 in comparison to 207 counts fg-1 measured with the PFA-100 nebulizer. Recovery using 242Pu tracer was about 70%. The limits of detection for 239Pu in 1 l of urine, based on an enrichment factor of 100 for PFA-100 nebulizer and 1000 for DIHEN, were 9×10-18 and 1.02×10-18 g ml-1, respectively. Measurements of 240Pu/239Pu isotopic ratio in synthetically prepared urine standard solution yielded a precision of 1.8 and 1.9% and accuracy of 1.5 and 1.8% for the PFA-100 and DIHEN nebulizers, respectively.

  19. Determination of ammonium and organic bound nitrogen by inductively coupled plasma emission spectroscopy.

    PubMed

    Jaber, A M Y; Mehanna, N A; Sultan, S M

    2009-06-15

    The continuous flow sample introduction technique with a hydride generator system in conjunction with an inductively coupled plasma emission spectrometer (ICP-AES-HG), is used in this study for quantitative determination of ammonium and organic bound nitrogen in aqueous and solid samples. Ammonia vapor released from ammonium salt after treatment with concentrated NaOH is transferred by argon to plasma for detection at 174.273 nm using axial argon plasma mode. The calibration curves were linear within a range of 25-1000 mg L(-1)N as ammonium molybdate with correlation coefficients of better than 0.99 and limits of detection of about 10-25mg L(-1)N. The percent recovery of N (25-500 mg L(-1)N) in soft (distilled) water and high salt content (1.7 mol L(-1) NaCl) matrices was found to be in the range of about 97-102% with %RSD in the range of 4.6-0.62. The sensitivity, limit of detection, and blank contribution from the atmospheric nitrogen, were tremendously improved in this method compared with the available ICP-AES spray chamber counterpart. Furthermore, the ICP-AES-HG method gave results for real samples (soil, fertilizer, waste water) containing about 50-1800 mg L(-1)N in good agreement with those obtained by the standard Kjeldahl method. No statistical differences at the 95% confidence level on applying the t-test were observed between the values obtained by the two methods. Thus, the ICP-AES-HG method is reliable and faster than the conventional tedious Kjeldahl method, superior to the ICP-AES spray chamber method, and almost free from matrix interference which is usually a critical factor in atomic emission spectroscopic techniques. PMID:19362191

  20. Determination of minor elements in steelmaking flue dusts using laser ablation inductively coupled plasma mass spectrometry.

    PubMed

    Coedo, A G; Padilla, I; Dorado, M T

    2005-07-15

    Element determination in solid waste products from the steel industry usually involves the time-consuming step of preparing a solution of the solid. Laser ablation (LA) inductively coupled plasma mass spectrometry (ICP-MS) has been applied to the analysis of Cr, Ni, Cu, As, Cd and Sn, elements of importance from the point of view of their impact on the environment, in electric arc furnace flue dust (EAFD). A simple method of sample preparation as pressed pellets using a mixture of cellulose and paraffin as binder material was applied. Calibration standards were prepared spiking multielement solution standards to a 1:1 ZnO+Fe(2)O(3) synthetic matrix. The wet powder was dried and mechanically homogenised. Quantitative analysis were based on external calibration using a set of matrix matched calibration standards with Rh as a internal standard. Results obtained using only one-point for calibration without matrix matched, needing less time for standardization and data processing, are also presented. Data are calculated for flue dust reference materials: CRM 876-1 (EAFD), AG-6203 (EAFD), AG-6201 (cupola dust) and AG-SX3705 (coke ashes), and for two representative electrical arc furnace flue dusts samples from Spanish steelmaking companies: MS-1 and MS-2. For the reference materials, an acceptable agreement with certificate values was achieved, and the results for the MS samples matched with those obtained from conventional nebulization solutions (CN). The analytical precision was found to be better than 7% R.S.D. both within a single pellet and between several pellets of the same sample for all the elements. PMID:18970147

  1. Langmuir Probe and Mass Spectroscopic Measurements in Inductively Coupled CF4 Plasmas

    NASA Technical Reports Server (NTRS)

    Rao, M. V. V. S.; Sharma, Surendra; Cruden, B. A.; Meyyappan, M.

    2001-01-01

    Abstract Electron and ion energy distribution functions and other plasma parameters such as plasma potential (V(sub p)) , electron temperature (T(sub e)), and electron and ion number densities (n (sub e) and n(sub i)) in low pressure CF4 plasmas have been measured. The experiments were conducted in a GEC cell using an inductively coupled plasma (ICP) device powered by a 13.56 MHz radio-frequency (rf) power source. The measurements were made at 300 W of input rf power at 10, 30 and 50 mTorr gas pressures. Langmuir probe measurements suggest that n(sub e), n(sub i) and V(sub p) remain constant over 60% of the central electrode area, beyond which they decrease. Within the limits of experimental error (+/- 0.25 eV), T(sub e) remains nearly constant over the electrode area. T(sub e) and V(sub p) increase with a decrease in pressure. n(sub e) and n(sub i) are not affected as significantly as T(sub e) or V(sub p) by variation in the gas pressure. The electron energy distribution function (EEDF) measurements indicate a highly non-Maxwellian plasma. CF3+ is the most dominant ion product of the plasma, followed by CF2+ and CF+. The concentrations of CF2+ and CF+ are much larger than that is possible from direct electron impact ionization of the parent gas. The cross-section data suggest that the direct electron impact ionization of fragment neutrals and negative ion production by electron attachment may be responsible for increase of the minor ions.

  2. Electromagnetic wave attenuation measurements in a ring-shaped inductively coupled air plasma

    SciTech Connect

    Xiaolong, Wei; Haojun, Xu; Min, Lin; Chen, Su; Jianhai, Li

    2015-05-28

    An aerocraft with the surface, inlet and radome covered large-area inductive coupled plasma (ICP) can attenuate its radar echo effectively. The shape, thickness, and electron density (N{sub e}) distribution of ICP are critical to electromagnetic wave attenuation. In the paper, an air all-quartz ICP generator in size of 20 × 20 × 7 cm{sup 3} without magnetic confinement is designed. The discharge results show that the ICP is amorphous in E-mode and ring-shaped in H-mode. The structure of ICP stratifies into core region and edge halo in H-mode, and its width and thickness changes from power and pressure. Such phenomena are explained by the distribution of RF magnetic field, the diffusion of negative ions plasma and the variation of skin depth. In addition, the theoretical analysis shows that the N{sub e} achieves nearly uniform within the electronegative core and sharply steepens in the edge. The N{sub e} of core region is diagnosed by microwave interferometer under varied conditions (pressure in range of 10–50 Pa, power in 300–700 W). Furthermore, the electromagnetic wave attenuation measurements were carried out with the air ICP in the frequencies of 4–5 GHz. The results show that the interspaced ICP is still effective to wave attenuation, and the wave attenuation increases with the power and pressure. The measured attenuation is approximately in accordance with the calculation data of finite-different time-domain simulations.

  3. Multi-Collector Inductively Coupled Plasma Mass Spectrometer – Operational Performance Report

    SciTech Connect

    Matthew Watrous; Anthony Appelhans; Robert Hague; John Olson; Tracy Houghton

    2013-06-01

    The INL made an assessment of the commercially available inductively coupled plasma mass spectrometers (ICPMS) for actinide analysis; emphasizing low detection limits for plutonium. INL scientists subsequently determined if plutonium was present on a swipe, at a 10 million atom decision level. This report describes the evaluation of ICPMS instruments and the operational testing of a new process for the dissolution, separation and analysis via ICPMS of swipes for plutonium and uranium. The swipe dissolution, plutonium and uranium isolation, separation and purification are wet chemistry methods following established procedures. The ICPMS is a commercially available multi-collector magnetic sector mass spectrometer that utilizes five ion counting detectors operating simultaneously. The instrument includes a sample introduction system allowing for sample volumes of < 1 mL to be reproducibly injected into the instrument with minimal waste of the sample solution, while maximizing the useable signal. The performance of the instrument was measured using SRM 996 (244Pu spike) at concentrations of 12 parts per quadrillion (ppq, fg/mL) and with SRM 4350B Columbia River Sediment samples spiked onto swipes at the 10 million atom level. The measured limit of detection (LOD, defined as 3s) for 239Pu is 310,000 atoms based upon the instrument blank data. The limit of quantification (LOQ defined as 10 s) for 239Pu is 105,000 atoms. The measured limit of detection for 239Pu from the SRM 4350B spiked onto a swipe was 2.7 million atoms with the limit of quantification being 9.0 million atoms.

  4. Calibration of laser ablation inductively coupled plasma mass spectrometry for quantitative measurements of lead in bone.

    PubMed

    Bellis, David J; Hetter, Katherine M; Jones, Joseph; Amarasiriwardena, Dula; Parsons, Patrick J

    2006-01-01

    Lead accumulates in bone over many years or decades. Accordingly, the study of lead in bone is important in determining the fate of ingested lead, the potential for remobilization, and for the application of bone lead measurements as a biomarker of lead exposure. Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) was used to measure the spatial distribution of lead in bone on the micrometer scale. In general, LA-ICP-MS studies are somewhat limited by the lack of matrix-matched standards and/or reference materials for calibration and validation purposes. Here we describe the application of pressed pellets prepared from New York State Department of Health candidate Reference Materials for Lead in Bone (levels 1 through 4), to provide a linear calibration for (208)Pb/(43)Ca in the concentration range <1 to 30 μg g(-1). The limit of detection was estimated as 0.2 μg g(-1). The measured lead values for pelletized NIST SRM 1486 Bone Meal and SRM 1400 Bone Ash were in good agreement with certified reference values. Using this approach, we quantitatively measured the spatial distribution of lead in a cross-section of goat metacarpal from a lead-dosed animal. The lead content was spatially variable in the range of 2 to 30 μg g(-1) with a complex distribution. In some sections, lead appeared to be enriched in the center of the bone relative to peripheral areas, indicating preferential accumulation in trabecular (spongy) rather than cortical bone. In addition, there were discrete areas of lead enrichment, or hot spots, of 100 to 200 μm in width. PMID:22833692

  5. Calibration of laser ablation inductively coupled plasma mass spectrometry for quantitative measurements of lead in bone

    PubMed Central

    Bellis, David J.; Hetter, Katherine M.; Jones, Joseph; Amarasiriwardena, Dula

    2012-01-01

    Summary Lead accumulates in bone over many years or decades. Accordingly, the study of lead in bone is important in determining the fate of ingested lead, the potential for remobilization, and for the application of bone lead measurements as a biomarker of lead exposure. Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) was used to measure the spatial distribution of lead in bone on the micrometer scale. In general, LA-ICP-MS studies are somewhat limited by the lack of matrix-matched standards and/or reference materials for calibration and validation purposes. Here we describe the application of pressed pellets prepared from New York State Department of Health candidate Reference Materials for Lead in Bone (levels 1 through 4), to provide a linear calibration for 208Pb/43Ca in the concentration range <1 to 30 μg g−1. The limit of detection was estimated as 0.2 μg g−1. The measured lead values for pelletized NIST SRM 1486 Bone Meal and SRM 1400 Bone Ash were in good agreement with certified reference values. Using this approach, we quantitatively measured the spatial distribution of lead in a cross-section of goat metacarpal from a lead-dosed animal. The lead content was spatially variable in the range of 2 to 30 μg g−1 with a complex distribution. In some sections, lead appeared to be enriched in the center of the bone relative to peripheral areas, indicating preferential accumulation in trabecular (spongy) rather than cortical bone. In addition, there were discrete areas of lead enrichment, or hot spots, of 100 to 200 μm in width. PMID:22833692

  6. Ultracentrifugation and inductively coupled plasma mass spectrometry for metal-protein equilibrium studies

    NASA Astrophysics Data System (ADS)

    Arnquist, Isaac J.; Holcombe, James A.

    2012-10-01

    The coupling of separation by preparative ultracentrifugation and metal detection by inductively coupled plasma mass spectrometry (ICP-MS) has been explored for metal-protein equilibrium determinations. This study characterizes the stoichiometry as well as apparent (Kapp) and intrinsic (Kint) binding affinities of the metal-protein association for a model protein. In particular, the affinity of Cu2 + for the high affinity binding site in bovine serum albumin (BSA) is determined. Once equilibrium is established between Cu2 + and BSA, preparative ultracentrifugation moves the metalloprotein away from the meniscus, leaving unbound equilibrium copper in the protein free solution. Since the initial (total) concentrations of purified BSA and Cu2 + can be determined, the free copper concentration at equilibrium can also be determined by taking a small aliquot above the sedimenting boundary for analysis using ICP-MS. This analysis allows for the determination of free Cu2 + ion, which is identical to the equilibrium concentration prior to ultracentrifugation. From these data Kapp and Kint were determined at two different conditions, 100 mM Tris(hydroxymethyl)aminomethane (Tris) at pH 9.53 and pH 7.93. log Kapp values of 17.6 and 14.6 were determined at pH 9.53 and pH 7.93, respectively. Furthermore, pH-independent log Kint values of - 1.43 and - 1.04 were determined at pH 9.53 and 7.93, respectively. While the log Kint at pH 9.53 was in good agreement with literature values obtained from alternative methods, Kint at pH 7.93 was about 2.5 × larger than previously reported. BSA undergoes a structural rearrangement between pH 7-9, and the generally accepted pH-dependency of protein tertiary structure may be responsible for the variations in the "intrinsic" binding constant. The Cu-BSA binding affinity was also monitored in 100 mM Tris 0.1% sodium dodecyl sulfate (SDS) solution at pH 7.93 in order to determine the effect of a denaturant on metal binding. Results for both log

  7. Liquid sample introduction in inductively coupled plasma atomic emission and mass spectrometry - Critical review

    NASA Astrophysics Data System (ADS)

    Bings, N. H.; Orlandini von Niessen, J. O.; Schaper, J. N.

    2014-10-01

    Inductively coupled plasma optical emission spectroscopy (ICP-OES) and mass spectrometry (ICP-MS) can be considered as the most important tools in inorganic analytical chemistry. Huge progress has been made since the first analytical applications of the ICP. More stable RF generators, improved spectrometers and detection systems were designed along with the achievements gained from advanced microelectronics, leading to overall greatly improved analytical performance of such instruments. In contrast, for the vast majority of cases liquid sample introduction is still based on the pneumatic principle as described in the late 19th century. High flow pneumatic nebulizers typically demand the use of spray chambers as “aerosol filters” in order to match the prerequisites of an ICP. By this, only a small fraction of the nebulized sample actually contributes to the measured signal. Hence, the development of micronebulizers was brought forward. Those systems produce fine aerosols at low sample uptake rates, but they are even more prone for blocking or clogging than conventional systems in the case of solutions containing a significant amount of total dissolved solids (TDS). Despite the high number of publications devoted to liquid sample introduction, it is still considered the Achilles' heel of atomic spectrometry and it is well accepted, that the technology used for liquid sample introduction is still far from ideal, even when applying state-of-the-art systems. Therefore, this review is devoted to offer an update on developments in the field liquid sample introduction that had been reported until the year 2013. The most recent and noteworthy contributions to this field are discussed, trends are highlighted and future directions are outlined. The first part of this review provides a brief overview on theoretical considerations regarding conventional pneumatic nebulization, the fundamentals on aerosol generation and discusses characteristics of aerosols ideally suited

  8. Controlling the relative rates of adlayer formation and removal during etching in inductively coupled plasmas

    NASA Astrophysics Data System (ADS)

    Fuller, Nicholas Colvin Masi

    Laser desorption (LD) of the adlayer coupled with laser induced fluorescence (LIF) and plasma induced emission (PIE) of desorbed adsorbates is used to investigate the relative rates of chlorination and sputtering during the etching of Si in inductively coupled Cl2-Ar plasmas. Such an analysis is a two-fold process: surface analysis and plasma characterization. Surface analysis of Si etching using LD-LIF and LD-PIE techniques combined with etch rate measurements have revealed that the coverage of SiCl2 and etch rate increases and coverage of Si decreases abruptly for a chlorine fraction of 75% and ion energy of 80 eV. The precise Cl2 fraction for which these abrupt changes occur increases with an increase in ion energy. These changes may be caused by local chemisorption-induced reconstruction of Si <100>. Furthermore, the chlorination and sputtering rates are increased by ˜ an order of magnitude as the plasma is changed from Ar-dominant to Cl-dominant. Characterization of the plasma included determination of the dominant ion in Cl2 plasmas using LIF and a Langmuir probe and measurement of the absolute densities of Cl2, Cl, Cl+, and At + in Cl2-Ar discharges using optical emission actinometry. These studies reveal that Cl+ is the dominant positive ion in the H-mode and the dissociation of Cl2 to Cl increases with an increase in Ar fraction due to an increase in electron temperature. Furthermore, for powers exceeding 600 W, the neutral to ion flux ratio is strongly dependent on Cl2 fraction and is attributed mostly to the decrease in Cl density. Such dependence of the flux ratio on Cl2 fraction is significant in controlling chlorination and sputtering rates not only for Si etching, but for etching other key technological materials. ICP O2 discharges were also studied for low-kappa polymeric etch applications. These studies reveal that the electron temperature is weakly dependent on rf power and O2 dissociation is low (˜2%) at the maximum rf power density of 5.7 Wcm

  9. Controlled Dissolution of Surface Layers for Elemental Analysis by Inductively Coupled Plasma-Mass Spectrometry

    SciTech Connect

    Susan Elizabeth Lorge

    2007-12-01

    Determining the composition of thin layers is increasingly important for a variety of industrial materials such as adhesives, coatings and microelectronics. Secondary ion mass spectrometry (SIMS), Auger electron spectroscopy (AES), X-ray photoelectron spectroscopy (XPS), glow discharge optical emission spectroscopy (GDOES), glow discharge mass spectrometry (GDMS), and laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) are some of the techniques that are currently employed for the direct analysis of the sample surface. Although these techniques do not suffer from the contamination problems that often plague sample dissolution studies, they do require matrix matched standards for quantification. Often, these standards are not readily available. Despite the costs of clean hoods, Teflon pipette tips and bottles, and pure acids, partial sample dissolution is the primary method used in the semiconductor industry to quantify surface impurities. Specifically, vapor phase decomposition (VPD) coupled to ICP-MS or total reflection x-ray fluorescence (TXRF) provides elemental information from the top most surface layers at detection sensitivities in the 10{sup 7}-10{sup 10}atoms/cm{sup 2} range. The ability to quantify with standard solutions is a main advantage of these techniques. Li and Houk applied a VPD-like technique to steel. The signal ratio of trace element to matrix element was used for quantification. Although controlled dissolution concentrations determined for some of the dissolved elements agreed with the certified values, concentrations determined for refractory elements (Ti, Nb and Ta) were too low. LA-ICP-MS and scanning electron microscopy (SEM) measurements indicated that carbide grains distributed throughout the matrix were high in these refractory elements. These elements dissolved at a slower rate than the matrix element, Fe. If the analyte element is not removed at a rate similar to the matrix element a true representation of the

  10. Determination of Sulfur in High-Level Waste Sludge by Inductively Coupled Plasma-Atomic Emission Spectroscopy and Ion Chromatography

    SciTech Connect

    COLEMAN, CJ

    2004-04-22

    Significant differences (approximately 30 percent) have been observed in the sulfur measurements in high-level waste sludge by the Analytical Development Section (ADS) using the inductively coupled plasma-atomic emission spectroscopy (ICP-AES) method compared with the ADS ion chromatography (IC) method. Since the measured concentrations of sulfur in the sludge approached the maximum concentration that can be processed in the DWPF, experiments were performed to determine the source of the differences and assess the true accuracy of sulfur measurements.

  11. The Spatial Effects of Antenna Configuration in a Large Area Inductively Coupled Plasma System for Flat Panel Displays

    NASA Astrophysics Data System (ADS)

    Seon-Geun, Oh; Young-Jun, Lee; Jae-Hong, Jeon; Jong-Hyeon, Seo; Hee-Hwan, Choe

    2014-08-01

    Spatial distributions of plasma parameters such as electron density, electron temperature and electric potential were investigated using a commercial simulation software (COMSOLTM) to predict the effects of antenna configuration in a large area inductively coupled plasma (ICP) system for flat panel displays. Nine planar antenna sets were evenly placed above a ceramic window. While the electron density was influenced by both the input current and gas pressure, the electron temperature and electric potential were dominantly affected by the gas pressure.

  12. [Determination of trace elements in sika bone powder by inductively coupled plasma mass spectrometry with microwave digestion].

    PubMed

    Liu, Yan-Ming; Chen, Zhi-Yong; Han, Jin-Tu; Wang, Hui; Wang, Zhi-Wen

    2006-05-01

    Contents of trace elements in sika bone powder were determined with microwave digestion and inductively coupled plasma mass spectrometry. Under the optimum conditions, the detection limits (3sigma, n = 11) are in the range of 0. 000 6-1. 498 ng x mL(-1) with relative standard deviations of 1.7%-6.8%. The recoveries are between 91% and 109%. The analytical results of national certified reference demonstrated the applicability of the proposed method. PMID:16883876

  13. Dynamics of Time Delay-Induced Multiple Synchronous Behaviors in Inhibitory Coupled Neurons

    PubMed Central

    Gu, Huaguang; Zhao, Zhiguo

    2015-01-01

    The inhibitory synapse can induce synchronous behaviors different from the anti-phase synchronous behaviors, which have been reported in recent studies. In the present paper, synchronous behaviors are investigated in the motif model composed of reciprocal inhibitory coupled neurons with endogenous bursting and time delay. When coupling strength is weak, synchronous behavior appears at a single interval of time delay within a bursting period. When coupling strength is strong, multiple synchronous behaviors appear at different intervals of time delay within a bursting period. The different bursting patterns of synchronous behaviors, and time delays and coupling strengths that can induce the synchronous bursting patterns can be well interpreted by the dynamics of the endogenous bursting pattern of isolated neuron, which is acquired by the fast-slow dissection method, combined with the inhibitory coupling current. For an isolated neuron, when a negative impulsive current with suitable strength is applied at different phases of the bursting, multiple different bursting patterns can be induced. For a neuron in the motif, the inhibitory coupling current, of which the application time and strength is modulated by time delay and coupling strength, can cause single or multiple synchronous firing patterns like the negative impulsive current when time delay and coupling strength is suitable. The difference compared to the previously reported multiple synchronous behaviors that appear at time delays wider than a period of the endogenous firing is discussed. The results present novel examples of synchronous behaviors in the neuronal network with inhibitory synapses and provide a reasonable explanation. PMID:26394224

  14. Relationship between the discharge mode and the spatial oxygen plasma distribution in a large size ferrite inductively coupled plasmas

    SciTech Connect

    Kim, Hyun Jun; Hwang, Hye Ju; Cho, Jeong Hee; Chae, Hee Sun; Kim, Dong Hwan; Chung, Chin-Wook

    2015-04-15

    The electrical characteristics and the spatial distribution of oxygen plasma according to the number of turns in ferrite inductively coupled plasmas (ferrite ICPs) are investigated. Through a new ICP model, which includes the capacitive coupling and the power loss of the ferrite material with the conventional ICP model, the variation of the oxygen discharge characteristics depending on the number of turns is simply understood by the electrical measurement, such as the antenna voltages and the currents. As the number of the turns increases, the capacitive coupling dominantly affects the spatial plasma distribution. This capacitive coupling results in a center focused density profile along the radial direction. In spite of the same discharge conditions (discharge chamber, neutral gas, and pressure), the spatial plasma distribution over 450 mm has drastic changes by increasing number of the turns. In addition, the effect of the negative species to the density profile is compared with the argon discharge characteristics at the same discharge configuration.

  15. Elemental analysis of biological samples by graphite furnace, inductively coupled plasma - atomic emission spectroscopy (GF-ICP-AES)

    SciTech Connect

    Winge, R.K.; Fassel, V.A.; Grabau, F.; Zu-cheng, J.

    1984-08-01

    The large number of analyses required for monitoring environmental pollution and its ecological impacts suggests that an analytical screening method would be very useful if it could rapidly distinguish those samples containing environmentally significant concentrations of pollutants from those that do not. In the trace elemental analysis of solids the most time consuming step is often the conversion of the sample into a suitable analytical form, usually a digestion and dissolution process. We have addressed these problems by combining a graphite furnace with inductively coupled plasma-atomic emission spectroscopy. With this system solid samples of plant and animal tissue, as well as solutions, can be vaporized and introduced directly into the inductively coupled plasma. A simple standard additions technique was developed for solid samples that yielded acceptable results for a number of elements in biological samples. Powers of detection were not satisfactory for the lowest concentrations of several elements in the NBS biological SRMs and analytical uncertainties were relatively high for quantitative analyses but were generally satisfactory for screening methods. The design of the interface between the graphite furnace and the inductively coupled plasma and the pulse effect caused by the vaporization of the sample are critical factors in the GF-ICP-AES method. 31 references, 21 figures, 4 tables.

  16. Coupling of a gas chromatograph to a simultaneous-detection inductively coupled plasma mass spectrograph for speciation of organohalide and organometallic compounds

    SciTech Connect

    Barnes, James H.; Schilling, G; Sperline, Roger; Denton, M Bonner B.; Young, Erick T.; Barinaga, Charles J.; Koppenaal, David W.; Hieftje, Gary M.

    2004-06-01

    A gas chromatograph (GC) has been coupled to an inductively coupled plasma Mattauch-Herzog geometry mass spectrograph (ICP-MHMS) equipped with a novel detector array. In its current state of development the detector array, termed the focal plan camera (FPC), permits the simultaneous monitoring of up to 15 m/z values. A heated line was used to transfer the capillary-column effluent from the GC to the ICP torch, though due to instrument operating conditions, the transfer line was terminated 50 mm ahead of the ICP torch. Minimal tailing was observed, with the most severe effect seen for high-boiling analytes. With the coupling, absolute limits of detection are in the tens to hundreds of femtogram regime for organometallic species and in the single pictogram regime for halogenated hydrocarbons.

  17. {sup 99}Tc bioassay by inductively coupled plasma mass spectrometry (ICP-MS)

    SciTech Connect

    Lewis, L.A.

    1998-05-01

    A means of analyzing {sup 99}Tc in urine by inductively coupled plasma mass spectrometry (ICP-MS) has been developed. Historically, {sup 99}Tc analysis was based on the radiometric detection of the 293 keV E{sub Max} beta decay product by liquid scintillation or gas flow proportional counting. In a urine matrix, the analysis of{sup 99}Tc is plagued with many difficulties using conventional radiometric methods. Difficulties originate during chemical separation due to the volatile nature of Tc{sub 2}O{sub 7} or during radiation detection due to color or chemical quenching. A separation scheme for {sup 99}Tc detection by ICP-MS is given and is proven to be a sensitive and robust analytical alternative. A comparison of methods using radiometric and mass quantitation of {sup 99}Tc has been conducted in water, artificial urine, and real urine matrices at activity levels between 700 and 2,200 dpm/L. Liquid scintillation results based on an external standard quench correction and a quench curve correction method are compared to results obtained by ICP-MS. Each method produced accurate results, however the precision of the ICP-MS results is superior to that of liquid scintillation results. Limits of detection (LOD) for ICP-MS and liquid scintillation detection are 14.67 and 203.4 dpm/L, respectively, in a real urine matrix. In order to determine the basis for the increased precision of the ICP-MS results, the detection sensitivity for each method is derived and measured. The detection sensitivity for the {sup 99}Tc isotope by ICP-MS is 2.175 x 10{sup {minus}7} {+-} 8.990 x 10{sup {minus}9} and by liquid scintillation is 7.434 x 10{sup {minus}14} {+-} 7.461 x 10{sup {minus}15}. A difference by seven orders of magnitude between the two detection systems allows ICP-MS samples to be analyzed for a period of 15 s compared to 3,600 s by liquid scintillation counting with a lower LOD.

  18. Self-consistent multidimensional electron kinetic model for inductively coupled plasma sources

    NASA Astrophysics Data System (ADS)

    Dai, Fa Foster

    Inductively coupled plasma (ICP) sources have received increasing interest in microelectronics fabrication and lighting industry. In 2-D configuration space (r, z) and 2-D velocity domain (νθ,νz), a self- consistent electron kinetic analytic model is developed for various ICP sources. The electromagnetic (EM) model is established based on modal analysis, while the kinetic analysis gives the perturbed Maxwellian distribution of electrons by solving Boltzmann-Vlasov equation. The self- consistent algorithm combines the EM model and the kinetic analysis by updating their results consistently until the solution converges. The closed-form solutions in the analytical model provide rigorous and fast computing for the EM fields and the electron kinetic behavior. The kinetic analysis shows that the RF energy in an ICP source is extracted by a collisionless dissipation mechanism, if the electron thermovelocity is close to the RF phase velocities. A criterion for collisionless damping is thus given based on the analytic solutions. To achieve uniformly distributed plasma for plasma processing, we propose a novel discharge structure with both planar and vertical coil excitations. The theoretical results demonstrate improved uniformity for the excited azimuthal E-field in the chamber. Non-monotonic spatial decay in electric field and space current distributions was recently observed in weakly- collisional plasmas. The anomalous skin effect is found to be responsible for this phenomenon. The proposed model successfully models the non-monotonic spatial decay effect and achieves good agreements with the measurements for different applied RF powers. The proposed analytical model is compared with other theoretical models and different experimental measurements. The developed model is also applied to two kinds of ICP discharges used for electrodeless light sources. One structure uses a vertical internal coil antenna to excite plasmas and another has a metal shield to prevent the

  19. Investigation of a measure of robustness in inductively coupled plasma mass spectrometry

    NASA Astrophysics Data System (ADS)

    Makonnen, Yoseif; Beauchemin, Diane

    2015-01-01

    In industrial/commercial settings where operators often have minimal expertise in inductively coupled plasma (ICP) mass spectrometry (MS), there is a prevalent need for a response factor indicating robust plasma conditions, which is analogous to the Mg II/Mg I ratio in ICP optical emission spectrometry (OES), whereby a Mg II/Mg I ratio of 10 constitutes robust conditions. While minimizing the oxide ratio usually corresponds to robust conditions, there is no specific target value that is widely accepted as indicating robust conditions. Furthermore, tuning for low oxide ratios does not necessarily guarantee minimal matrix effects, as they really address polyatomic interferences. From experiments, conducted in parallel for both MS and OES, there were some element pairs of similar mass and very different ionization potential that were exploited for such a purpose, the rationale being that, if these elements were ionized to the same extent, then that could be indicative of a robust plasma. The Be II/Li I intensity ratio was directly related to the Mg II/Mg I ratio in OES. Moreover, the 9Be+/7Li+ ratio was inversely related to the CeO+/Ce+ and LaO+/La+ oxide ratios in MS. The effects of different matrices (i.e. 0.01-0.1 M Na) were also investigated and compared to a conventional argon plasma optimized for maximum sensitivity. The suppression effect of these matrices was significantly reduced, if not eliminated in the case of 0.01 M Na, when the 9Be+/7Li+ ratio was around 0.30 on the Varian 820 MS instrument. Moreover, a very similar ratio (0.28) increased robustness to the same extent on a completely different ICP-MS instrument (PerkinElmer NEXION). Much greater robustness was achieved using a mixed-gas plasma with nitrogen in the outer gas and either nitrogen or hydrogen as a sheathing gas, as the 9Be+/7Li+ ratio was then around 1.70. To the best of our knowledge, this is the first report on using a simple analyte intensity ratio, 9Be+/7Li+, to gauge plasma robustness.

  20. Evaluation of the analytical capability of NIR femtosecond laser ablation-inductively coupled plasma mass spectrometry.

    PubMed

    Hirata, Takafumi; Kon, Yoshiaki

    2008-03-01

    A laser ablation-inductively coupled plasma-mass spectrometric (LA-ICPMS) technique utilizing a titanium-sapphire (TiS) femtosecond laser (fs-laser) has been developed for elemental and isotopic analysis. The signal intensity profile, depth of the ablation pit and level of elemental fractionation were investigated in order to evaluate the analytical capability of the present fs-laser ablation-ICPMS technique. The signal intensity profile of (57)Fe, obtained from iron sulfide (FeS(2)), demonstrated that the resulting signal intensity of (57)Fe achieved by the fs-laser ablation was almost 4-times higher than that obtained by ArF excimer laser ablation under a similar energy fluence (5 J/cm(2)). In fs-laser ablation, there is no significant difference in a depth of the ablation pit between glass and zircon material, while in ArF laser ablation, the resulting crater depth on the zircon crystal was almost half the level than that obtained for glass material. Both the thermal-induced and particle size-related elemental fractionations, which have been thought to be main sources of analytical error in the LA-ICPMS analysis, were measured on a Harvard 91500 zircon crystal. The resulting fractionation indexes on the (206)Pb/(238)U (f(Pb/U)) and (238)U/(232)Th (f(U/Th)) ratios obtained by the present fs-laser ablation system were significantly smaller than those obtained by a conventional ArF excimer laser ablation system, demonstrative of smaller elemental fractionation. Using the present fs-laser ablation technique, the time profile of the signal intensity of (56)Fe and the isotopic ratios ((57)Fe/(54)Fe and (56)Fe/(54)Fe) have been measured on a natural pyrite (FeS(2)) sample. Repeatability in signal intensity of (56)Fe achieved by the fs-laser ablation system was significantly better than that obtained by ArF excimer laser ablation. Moreover, the resulting precision in (57)Fe/(54)Fe and (56)Fe/(54)Fe ratio measurements could be improved by the fs-laser ablation system

  1. Optical and electrical characterization of pulse-modulated argon atmospheric-pressure inductively coupled microplasma jets

    SciTech Connect

    Tajima, Satomi; Tsuchiya, Shouichi; Matsumori, Masashi; Nakatsuka, Shigeki; Ichiki, Takanori

    2010-10-15

    The critical parameters determining the generation of the pulse-modulated argon atmospheric-pressure inductively coupled plasma (AP-ICP) microjet were studied by varying the power, P, pulse-modulation frequency, f, and duty ratio, DR. The temporal changes in the net output power, P{sub net}, monitored between the very high frequency power supply and matching network by an rf sampler, and ArI 4s{sup '}[1/2]{sub 1}{sup O}-4p{sup '}[1/2]{sub 0} emission from the antenna were measured to elucidate the behavior of this plasma. The AP-ICP microjet, which produces high-density (0.9-1.1x10{sup 15} cm{sup -3}) nonequilibrium plasma, consists of an alumina discharge tube with the inner diameter of 0.8 mm. The generation diagram of the pulse-modulated plasma was created by having f as the horizontal axis and DR as the vertical axis while varying P up to 50 W. At f{<=}10 kHz, the plasma was generated at above the linear lines of f and DR, which indicated the existence of the critical power-off period of approximately 80 {mu}s. At f>10 kHz, the pulse-modulated plasma was produced above constant DR and almost independent of f. The time-averaged power, P, which is the product of P and DR, had to be more than 8-10 W to sustain the pulse-modulated plasma. From the measurement of the temporal changes in the net power and ArI emission, the dynamic behavior of the pulse-modulated plasma was revealed as follows. The prebreakdown period was present for {approx}5 {mu}s after the power was turned on. Once the plasma was generated, the impedance was changed and the reflected power gradually decreased. A strong emission peak was observed immediately after the breakdown, followed by the gradual increase up to the steady state. Finally, the intense afterpeak was observed at 0.8 {mu}s after the power was turned off.

  2. Lead geochronology of zircon by LaserProbe-inductively coupled plasma mass spectrometry (LP-ICPMS)

    NASA Astrophysics Data System (ADS)

    Feng, Rui; Machado, Nuno; Ludden, John

    1993-07-01

    LaserProbe-inductively coupled plasma mass spectrometry (LP-ICPMS) provides a sensitive, fast, and simple means to determine 207Pb /206Pb ages in single zircon grains. A Nd:YAG laser is used to irradiate the zircon surface and leaves a cylindrical pit of 30-60 μm, from which the vaporised materials are transported by argon gas to a Fisons-VG PQII+ ICPMS for analysis. No zircon abrasion, cleaning nor chemical separation procedures are required. The accuracy and the limitation of the method were evaluated by analyzing twenty-one zircon samples ranging in age from 2.7 Ga to 1.0 Ga, which have also been dated by the conventional U-Pb thermal ionization mass spectrometry technique (TIMS). The LP-ICPMS 207Pb /206Pb ages for zircons with grain size > 60 μm and 207Pb concentration > 3 ppm are within 1% of the TIMS ages. Smaller zircons (≤60 μm) and those with 207Pb concentration < 2 ppm yield inaccurate ages. Operating the LP-ICPMS at conditions that give a compromise between the ideal spatial resolution and instrument sensitivity, the limits of detection were found to be 0.2 ppm for 206Pb, 207Pb, and 208Pb. The precision of the 207Pb /206Pb ratio is generally 0.5-6% (1σ) from each sampling pit and is strongly dependent on the lead concentration. However, the precision for the average of the mean ratios from different pits in one grain or several grains of the same population are generally <1.5% (1σ). The results presented here demonstrate that the LP-ICPMS can be used to determine 207Pb /206Pb ages of zircons and that reliable ages can be obtained from high quality, limpid zircons with a simple Pb-loss history. Uses of the technique include screening of zircon populations from different rocks in areas of poorly known age relationships and provenance studies of detrital zircons from ancient and modern sedimentary sequences. Other applications include the study of growth zones and of inherited components in complex zircon populations. In comparison with the SHRIMP

  3. Pulsed Cl2/Ar inductively coupled plasma processing: 0D model versus experiments

    NASA Astrophysics Data System (ADS)

    Despiau-Pujo, E.; Brihoum, M.; Bodart, P.; Darnon, M.; Cunge, G.

    2014-11-01

    Comparisons between measurements and spatially-averaged (0D) simulations of low-pressure Ar and Cl2 pulsed-plasmas in an industrial inductively coupled reactor are reported. Our analysis focuses on the impact of the pulsing parameters (frequency f, duty cycle dc) on the chemical reactivity of the plasma and on the ion fluxes to the walls. Charged particle densities and ion fluxes are highly modulated when the plasma is pulsed at 1 kHz < f < 20 kHz. In rare gas Ar plasmas, the ion flux rise time is short (50 μs), therefore the dc has almost no influence on the ion flux value during the pulse. By contrast, in molecular electronegative Cl2 plasmas, both the value and rise/decay time of the ion flux during the on and off-periods depend strongly on the dc. This is because in Cl2 both the plasma chemistry and electronegativity depend on the dc. During the off-period, the electron density drops much faster than the negative ion density, leading to a large increase in plasma electronegativity. A minimum afterglow time (75 µs) is required for an ion-ion plasma to form and for the sheath to collapse, exposing the walls and wafers to a negative ion flux. The positive ion flux is 3 to 10 times smaller in Cl2 than in Ar for the same operating conditions. In contrast with charged species, the radical (Cl) kinetics are slow and thus the radical density is hardly modulated for f > 1 kHz. However, the dc strongly influences the Cl2/Cl density ratio and is an excellent knob for controlling the plasma chemical reactivity: the higher the dc the higher the Cl density. The trends and quantities in the 0D simulation are in close agreement with experiments. This proves the capacity of global models to reproduce the fundamental features of pulsed plasmas in simple chemistries and to assist the development of pulsed processes.

  4. ICPP: Low-frequency, inductively coupled plasma sources: operation and applications

    NASA Astrophysics Data System (ADS)

    Xu, Shuyan

    2000-10-01

    Low-frequency, inductively coupled plasmas (LFICP) have recently attracted great attention in connection with the plasma processing of materials. The low-frequency sources feature high plasma density (10^18 - 10^19 m-3), excellent uniformity over large areas, low electron temperature, moderate plasma potential, deeper RF filed penetration and high power transfer efficiency. This work presents a comprehensive experimental and theoretical investigation of the electric/electromagnetic properties, electron density and temperature, and the optical emission in 500 kHz ICP sources. A series of experiments conducted in Ar/N_2/H2 and CH4 discharges show that the high-density plasmas are generated in the two distinctive E- and H- operating regimes. Near the mode transitions the power reflection coefficient exhibits resonant minima. The optical emission spectra of neutral atoms and ions together with global power balance arguments reveal that the step-wise ionization via excited states can be responsible for delaying the backward transition between the H- and E- discharge states, and, hence, lead to hysteresis. The experimental and theoretical results on the discharge mode transitions and hysteresis are discussed as well. It is demonstrated that the low-frequency ICP source is extremely efficient for nitriding of solid materials, especially of stainless steel. A low-temperature ( 350^oC) steel nitriding experiments undertaken in plasmas of various Ar/N_2/H2 gas mixtures show that very high nitriding rates, ranging from 40 μm/hour (stainless steel AISI304) to 90 μm/hour (AISI410), can be achieved. The microstructure, phases and composition of the nitrided surface layers have been characterized by Scanning Electron Microscopy, x-ray photoelectron spectroscopy, x-ray diffraction spectroscopy and energy dispersive x-ray spectroscopy. It has been shown that the crystalline phases of the nitrided layer can efficiently be controlled by the processing conditions. The nitrogen

  5. Gas and liquid chromatography with inductively coupled plasma mass spectrometry detection for environmental speciation analysis — advances and limitations

    NASA Astrophysics Data System (ADS)

    Szpunar, Joanna; McSheehy, Shona; Połeć, Kasia; Vacchina, Véronique; Mounicou, Sandra; Rodriguez, Isaac; Łobiński, Ryszard

    2000-07-01

    Recent advances in the coupling of gas chromatography (GC) and high performance liquid chromatography (HPLC) with inductively coupled plasma mass spectrometry (ICP MS) and their role in trace element speciation analysis of environmental materials are presented. The discussion is illustrated with three research examples concerning the following topics: (i) development and coupling of multicapillary microcolumn GC with ICP MS for speciation of organotin in sediment and biological tissue samples; (ii) speciation of arsenic in marine algae by size-exclusion-anion-exchange HPLC-ICP MS; and (iii) speciation of cadmium in plant cell cultures by size-exclusion HPLC-ICP MS. Particular attention is paid to the problem of signal identification in ICP MS chromatograms; the potential of electrospray MS/MS for this purpose is highlighted.

  6. Methyl mercury in nail clippings in relation to fish consumption analysis with gas chromatography coupled to inductively coupled plasma mass spectrometry: a first orientation.

    PubMed

    Krystek, Petra; Favaro, Paulo; Bode, Peter; Ritsema, Rob

    2012-08-15

    For the identification of human exposure to one of the most toxic compounds, which is methyl mercury (MeHg(+)), fingernail clippings were selected as the matrix of interest. Within this pilot study, six samples from different origins and from people with different food consumption patterns were chosen. Species-analysis of MeHg(+) was performed according to the following procedure: dissolution of the sample material in tetramethylammonium hydroxide (TMAH), derivatisation of MeHg(+) with sodium tetraethylborate (NaBEt(4)), extraction into iso-octane and measurement with gas chromatography hyphenated to inductively coupled plasma mass spectrometry (GC-ICPMS) for the quantification MeHg(+). PMID:22841050

  7. Experimental observation of electron bounce resonance through electron energy distribution measurement in a finite size inductively coupled plasma

    NASA Astrophysics Data System (ADS)

    Gu, Seuli; Kang, Hyun-Ju; Kwon, Deuk-Chul; Kim, Yu-Sin; Chang, Yoon-Min; Chung, Chin-Wook

    2016-06-01

    The electron bounce resonance was experimentally investigated in a low pressure planar inductively coupled plasma. The electron energy probability functions (EEPFs) were measured at different chamber heights and the energy diffusion coefficients were calculated by the kinetic model. It is found that the EEPFs begin to flatten at the first electron bounce resonance condition, and the plateau shifts to a higher electron energy as the chamber height increases. The plateau which indicates strong electron heating corresponds not only to the electron bounce resonance condition but also to the peaks of the first component of the energy diffusion coefficients. As a result, the plateau formation in the EEPFs is mainly due to the electron bounce resonance in a finite inductive discharge.

  8. Fabrication and application of a wireless inductance-capacitance coupling microsensor with electroplated high permeability material NiFe

    NASA Astrophysics Data System (ADS)

    Chen, Y. H.; Chang, H. C.; Lai, C. C.; Chang, I. N.

    2011-01-01

    A fully integrated wireless inductance-capacitance (LC) coupling microsensor was designed and fabricated by MEMS technology. The sensing loop was formed by connecting a deformable parallel-plated capacitor and a planar spiral inductor with a Ni(80)Fe(20) core. Polyimide and PMMA were used to isolate and package the devices. Typical dimension of the sensors was 5 × 5 mm2 × 0.77 mm. Different electroplated inductive coils (30, 40, and 60 turns) were fabricated to connect with a 4 × 4 mm2 plate capacitor in series. The LC sensing module for measuring liquid-level induced frequency responses was setup. Experimental results show that frequency response decreased as liquid level increased and sensitivity is about 7.01 kHz/cm with deviation less than 2%. Developed planar spiral inductor with high permeability magnetic core can provide a wide range of frequency variation in LC sensing applications.

  9. A hybrid model in inductively coupled plasma discharges with bias source: Description of model and experimental validation in Ar discharge

    NASA Astrophysics Data System (ADS)

    Wen, De-Qi; Liu, Wei; Liu, Yong-Xin; Gao, Fei; Wang, You-Nian

    2015-09-01

    Traditional fluid simulation and Particle-in-Cell/Monte-Carlo collision (PIC/MCC) are very time consuming in inductively coupled plasma. In this work, a hybrid model, i.e. global model coupled bidirectional with parallel Monte-Carlo collision (MCC) sheath model, is developed to investigate inductively coupled plasma discharge with bias source. The global model is applied to calculate plasma density in bulk plasma. The sheath model is performed to consistently calculate the electric field, ion kinetic and the sheath thickness above the bias electrode. Moreover, specific numbers of ions are tracked and ultimately ion energy distribution functions (IEDFs) incident into bias electrode are obtained from MCC module. It is found that as the bias amplitude increases, the energy width of both IEDFs becomes wider, and the total outlines of IEDFs move towards higher energy. The results from the model are validated by experimental measurement and a qualitative agreement is obtained. The advantage of this model is that plasma density, ion flux and IEDF, which are widely concerned in the actual process, could be obtained within an hour. This work was supported by the National Natural Science Foundation of China (NSFC) (Grant No. 11205025 and 11335004) and (Grant No.11405018), the Important National Science and Technology Specific Project (Grant No. 2011ZX02403-001).

  10. Effects of matching network on the hysteresis during E and H mode transitions in argon inductively coupled plasma

    SciTech Connect

    Gao Fei; Zhao Shuxia; Li Xiaosong; Wang Younian

    2010-10-15

    An experimental investigation of the hysteresis during the E (capacitive coupling) and H mode (inductive coupling) transitions at various matching situation in argon inductively coupled plasma is reported. At high pressure, the results show two hysteresis loops involved the plasma density, applied power, and forward power, as well as the electrical parameters in the discharge circuit, when the series capacitance is cycled. The measured electron density versus applied power shows that the hysteresis loop shrinks with the decrease of the matching capacitance, and the same trend is discovered on the input current, voltage, and phase angle. In addition, for the case of small capacitance, the current (or voltage) jumps to a low value when the discharge passes through the E to H mode transition regime. Contrarily, for the case of large capacitance, the current jumps to a high value while the voltage is almost constant. The evolution characteristics of the plasma and circuit parameters observed imply that the nonlinear behavior of the matching situation may be one of the determined factors for hysteresis.

  11. Calibration and multi-layer inversion of multiple electromagnetic induction sensor data

    NASA Astrophysics Data System (ADS)

    von Hebel, Christian; van der Kruk, Jan; Mester, Achim; Altdorff, Daniel; Zimmermann, Egon; Endres, Anthony; Vereecken, Harry

    2016-04-01

    Multi-coil electromagnetic induction (EMI) sensors record simultaneously the apparent electrical conductivity (ECa) distribution of different integrated depths that can principally be used to invert for hydrologically relevant subsurface structures. However, EMI sensors induce not only magnetic fields in the subsurface but external conditions, e.g. the field setup, generate additional fields that shift the recorded ECa values. To obtain quantitative multi-coil EMI-ECa that make a multi-layer inversion possible, a post-calibration is required. Calibration for each coil configuration is performed using linear regressions between measured and predicted ECa that were obtained by inserting the electrical conductivities of inverted electrical resistivity tomography (ERT) data into a Maxwell-based EMI forward model. We measured 43 of these calibration lines using different field setups at various test sites and dates. Analyzing the data, we found a well-working calibration and a successful subsequent multi-layer inversion when relatively large lateral and vertical ECa values were found along the calibration line. However, we observed failure when either the measured or the predicted ECa range is < 3 mS/m and/or when the ground electrical conductivity is < 5 mS/m. Using selected calibration lines with coefficients of determination R2 > 0.75 in the linear regression equations, universal calibration parameters were obtained. Since the inversion of universally calibrated EMI-ECa returned similar subsurface structures as the ERT images, the results indicate that future ERT calibration measurements might become unnecessary. We also extended our three-layer inversion using one EMI sensor with 6 coil configurations to a combined multi-layer inversion of multiple sensors. Here, we preliminary show 4 and 5 layer inversion results of post-calibrated EMI-ECa measured above paleo-river channels with 24 coil configurations, i.e. DualEM plus a three- and a six coil CMD

  12. Characterization of a Second-generation Focal-plane Camera Coupled to an Inductively Coupled Plasma Mattauch-Herzog Geometry Mass Spectrograph

    SciTech Connect

    Schilling, G D.; Andrade, Francisco J.; Barnes, James H.; Sperline, Roger P.; Denton, M BONNER.; Barinaga, Charles J.; Koppenaal, David W.; Hieftje, Gary M.

    2006-07-01

    A second-generation Faraday-strip array detector has been coupled to an inductively coupled plasma Mattauch- Herzog geometry mass spectrograph, thereby offering simultaneous acquisition of a range of mass-to-charge ratios. The second-generation device incorporates narrower, more closely spaced collectors than the earlier system. Furthermore, the new camera can acquire signal on all collectors at a frequency greater than 2 kHz and has the ability to independently adjust the gain level of each collector. Each collector can also be reset independently. With these improvements, limits of detection in the hundreds of picograms per liter for metals in solution have been obtained. Some additional features, such as a broader linear dynamic range (over 7 orders of magnitude), greater resolving power (up to 600), and improved isotope ratio accuracy were attained. In addition, isotope ratio precision as low as 0.018% RSD was achieved.

  13. RAPID DETERMINATION OF ACTINIDES IN URINE BY INDUCTIVELY-COUPLED PLASMA MASS SPECTROMETRY AND ALPHA SPECTROMETRY: A HYBRID APPROACH

    SciTech Connect

    Maxwell, S.; Jones, V.

    2009-05-27

    A new rapid separation method that allows separation and preconcentration of actinides in urine samples was developed for the measurement of longer lived actinides by inductively coupled plasma mass spectrometry (ICP-MS) and short-lived actinides by alpha spectrometry; a hybrid approach. This method uses stacked extraction chromatography cartridges and vacuum box technology to facilitate rapid separations. Preconcentration, if required, is performed using a streamlined calcium phosphate precipitation. Similar technology has been applied to separate actinides prior to measurement by alpha spectrometry, but this new method has been developed with elution reagents now compatible with ICP-MS as well. Purified solutions are split between ICP-MS and alpha spectrometry so that long- and short-lived actinide isotopes can be measured successfully. The method allows for simultaneous extraction of 24 samples (including QC samples) in less than 3 h. Simultaneous sample preparation can offer significant time savings over sequential sample preparation. For example, sequential sample preparation of 24 samples taking just 15 min each requires 6 h to complete. The simplicity and speed of this new method makes it attractive for radiological emergency response. If preconcentration is applied, the method is applicable to larger sample aliquots for occupational exposures as well. The chemical recoveries are typically greater than 90%, in contrast to other reported methods using flow injection separation techniques for urine samples where plutonium yields were 70-80%. This method allows measurement of both long-lived and short-lived actinide isotopes. 239Pu, 242Pu, 237Np, 243Am, 234U, 235U and 238U were measured by ICP-MS, while 236Pu, 238Pu, 239Pu, 241Am, 243Am and 244Cm were measured by alpha spectrometry. The method can also be adapted so that the separation of uranium isotopes for assay is not required, if uranium assay by direct dilution of the urine sample is preferred instead

  14. Differentiation of colloidal and dissolved silica: Analytical separation using spectrophotometry and inductively coupled plasma atomic emission spectrometry

    USGS Publications Warehouse

    Lewis-Russ, A.; Ranville, J.; Kashuba, A.T.

    1991-01-01

    A method is described that differentiates between solutions containing silica-dominated colloids and solutions that are essentially free of colloids. Suspensions of tuff particles were treated to remove colloids by centrifugation, filtration or both. Agreement of silica concentrations determined by inductively coupled plasma atomic emission spectrometry and by a spectrophotometric method was taken as an indication of colloid-free solutions. For two tuffs, centrifugation was effective for removing colloids. For the third, highly altered tuff, filtration was more effective for removing colloids.

  15. Quantum fluctuations of mesoscopic damped double resonance RLC circuit with mutual capacitance inductance coupling in thermal excitation state

    NASA Astrophysics Data System (ADS)

    Xu, Xing-Lei; Li, Hong-Qi; Wang, Ji-Suo

    2007-08-01

    Based on the scheme of damped harmonic oscillator quantization and thermo-field dynamics (TFD), the quantization of mesoscopic damped double resonance RLC circuit with mutual capacitance-inductance coupling is proposed. The quantum fluctuations of charge and current of each loop in a squeezed vacuum state are studied in the thermal excitation case. It is shown that the fluctuations not only depend on circuit inherent parameters, but also rely on excitation quantum number and squeezing parameter. Moreover, due to the finite environmental temperature and damped resistance, the fluctuations increase with the temperature rising, and decay with time.

  16. Effect of Inductively Coupled Plasma on the Structural and Electrical Properties of Ti-Doped ITO Films Formed by IPVD.

    PubMed

    Hong, Chan-Hwa; Shin, Jae-Heon; Park, Nae-Man; Kim, Kyung-Hyun; Kim, Bo-Sul; Song, Chang-Woo; Yang, Ji-Woong; Seo, Woo-Hyung; Ju, Byeong-Kwon; Cheong, Woo-Seok

    2015-10-01

    In this study, we investigated Ti-doped ITO films formed through ionized physical vapor deposition (IPVD) using inductively coupled plasma (ICP). Ti-doped ITO thin films showed an enhanced mobility with ICP power; owing to the improved crystallinity, and the sheet resistance of the Ti-doped ITO (30 nm) largely decreased from 295.1 to 134.5 ohm/sq, even during at room temperature. Therefore, IPVD technology offers a useful tool for transparent electrodes with a large area window-unified touch-screen panel. PMID:26726469

  17. Inductively coupled plasma-atomic emission spectroscopy: a computer controlled, scanning monochromator system for the rapid determination of the elements

    SciTech Connect

    Floyd, M.A.

    1980-03-01

    A computer controlled, scanning monochromator system specifically designed for the rapid, sequential determination of the elements is described. The monochromator is combined with an inductively coupled plasma excitation source so that elements at major, minor, trace, and ultratrace levels may be determined, in sequence, without changing experimental parameters other than the spectral line observed. A number of distinctive features not found in previously described versions are incorporated into the system here described. Performance characteristics of the entire system and several analytical applications are discussed.

  18. Low Temperature Deposition of β-phase Silicon Nitride Using Inductively Coupled Plasma Chemical Vapor Deposition Technique

    NASA Astrophysics Data System (ADS)

    Kshirsagar, Abhijeet; Duttagupta, S. P.; Gangal, S. A.

    2010-12-01

    Silicon nitride (SiN) films have been deposited at low temperature (≤100° C), by Inductively Coupled Plasma Chemical Vapor Deposition (ICPCVD) technique. The chemical and physical properties of deposited SiN films such as refractive index, deposition rate, and film stress have been measured. Additional structural characterization is performed using X-ray diffraction (XRD) and Micro Raman Spectroscopy. It is found that the films obtained are of low stress and have β-phase. To the best of authors knowledge such low temperature, low stress, β-phase SiN films deposition using ICPCVD are being reported for the first time.

  19. Optimization of determination of platinum group elements in airborne particulate matter by inductively coupled plasma mass spectrometry.

    PubMed

    Bujdoš, Marek; Hagarová, Ingrid; Matúš, Peter; Canecká, Lucia; Kubová, Jana

    2012-03-01

    Determination of automotive traffic-emitted platinum group metals (PGM) by inductively coupled plasma quadrupole mass spectrometry (ICP-MS) was optimized. The interferences from Sr, Cu, Pb, Y, Cd, Zr and Hf were evaluated using model solutions. Plasma radiofrequency (RF) power and nebulizer gas flow were optimized for 103Rh, 105Pd, 108Pd and 195Pt. Two standard reference materials were analyzed: SARM-7 Platinum ore and BCR-723 Road dust. The optimized procedure was used to analyze samples of airborne particulate matter collected in the urban site with heavy automotive traffic in the centre of Bratislava, Slovakia. PMID:24061181

  20. Measurement of low radioactivity background in a high voltage cable by high resolution inductively coupled plasma mass spectrometry

    SciTech Connect

    Vacri, M. L. di; Nisi, S.; Balata, M.

    2013-08-08

    The measurement of naturally occurring low level radioactivity background in a high voltage (HV) cable by high resolution inductively coupled plasma mass spectrometry (HR ICP MS) is presented in this work. The measurements were performed at the Chemistry Service of the Gran Sasso National Laboratory. The contributions to the radioactive background coming from the different components of the heterogeneous material were separated. Based on the mass fraction of the cable, the whole contamination was calculated. The HR ICP MS results were cross-checked by gamma ray spectroscopy analysis that was performed at the low background facility STELLA (Sub Terranean Low Level Assay) of the LNGS underground lab using HPGe detectors.

  1. Methods of Analysis by the U.S. Geological Survey National Water Quality Laboratory - Determination of Elements in Whole-Water Digests Using Inductively Coupled Plasma-Optical Emission Spectrometry and Inductively Coupled Plasma-Mass Spectrometry

    USGS Publications Warehouse

    Garbarino, John R.; Struzeski, Tedmund M.

    1998-01-01

    Inductively coupled plasma-optical emission spectrometry (ICP-OES) and inductively coupled plasma-mass spectrometry (ICP-MS) can be used to determine 26 elements in whole-water digests. Both methods have distinct advantages and disadvantages--ICP-OES is capable of analyzing samples with higher elemental concentrations without dilution, however, ICP-MS is more sensitive and capable of determining much lower elemental concentrations. Both techniques gave accurate results for spike recoveries, digested standard reference-water samples, and whole-water digests. Average spike recoveries in whole-water digests were 100 plus/minus 10 percent, although recoveries for digests with high dissolved-solid concentrations were lower for selected elements by ICP-MS. Results for standard reference-water samples were generally within 1 standard deviation of hte most probable values. Statistical analysis of the results from 43 whole-water digest indicated that there was no significant difference among ICP-OES, ICP-MS, and former official methods of analysis for 24 of the 26 elements evaluated.

  2. Polariton Resonances for Ultrastrong Coupling Cavity Optomechanics in GaAs/AlAs Multiple Quantum Wells.

    PubMed

    Jusserand, B; Poddubny, A N; Poshakinskiy, A V; Fainstein, A; Lemaitre, A

    2015-12-31

    Polariton-mediated light-sound interaction is investigated through resonant Brillouin scattering experiments in GaAs/AlAs multiple-quantum wells. Photoelastic coupling enhancement at exciton-polariton resonance reaches 10(5) at 30 K as compared to a typical bulk solid room temperature transparency value. When applied to GaAs based cavity optomechanical nanodevices, this result opens the path to huge displacement sensitivities and to ultrastrong coupling regimes in cavity optomechanics with couplings g(0) in the range of 100 GHz. PMID:26765028

  3. Prolactin-stimulated ornithine decarboxylase induction in rat hepatocytes: Coupling to diacylglycerol generation and protein kinase C

    SciTech Connect

    Buckley, A.R.; Buckley, D.J. )

    1991-01-01

    The trophic effects of prolactin (PRL) in rat liver have been linked to activation of protein kinase C (PKC). Since alterations in PKC activity imply its activation by 1,2-diacylglycerol (DAG), we tested whether PRL treatment stimulated DAG generation coupled to induction of a growth response in primary hepatocytes. Addition of PRL to hepatocyte cultures significantly increased ({sup 3}H)-glycerol incorporation into DAG within 5 minutes which was followed by a loss of cytosolic PKC activity by 10 minutes. Prolactin also significantly enhanced radiolabel incorporation into triacylglycerol and phospholipids within 10 minutes and induced ODC activity at 6 hours. Therefore, prolactin-stimulated alterations in PKC activity are preceded by enhanced DAG generation. Moreover, these events appear to be coupled to PRL-stimulated entry of hepatocytes into cell cycle.

  4. Characterization of binary silver based alloys by nanosecond-infrared-laser-ablation-inductively coupled plasma-optical emission spectrometer

    NASA Astrophysics Data System (ADS)

    Márquez, Ciro; Sobral, Hugo

    2013-11-01

    A nanosecond infrared laser ablation (LA) system was examined to determine the composition of several silver-copper alloys through an inductively coupled plasma-optical emission spectrometer (ICP-OES). Samples with different concentrations were prepared and analyzed by atomic absorption, and ICP-OES after sample digestion, and compared with an energy-dispersive x-ray spectrometer-scanning electron microscopy (EDX-SEM). Elemental fractionation during the ablation process and within the ICP was investigated for different laser frequencies and fluences. Samples were used for optimizing and calibrating the coupling between LA to the ICP-OES system. Results obtained from the samples analysis were in agreement with those obtained by atomic absorption spectroscopy, ICP-OES and EDX-SEM, showing that fractionation was not significant for laser fluences higher than 55 J cm-2.

  5. A study on the maximum power transfer condition in an inductively coupled plasma using transformer circuit model

    SciTech Connect

    Kim, Young-Do; Lee, Hyo-Chang; Chung, Chin-Wook

    2013-09-15

    Correlations between the external discharge parameters (the driving frequency ω and the chamber dimension R) and plasma characteristics (the skin depth δ and the electron-neutral collision frequency ν{sub m}) are studied using the transformer circuit model [R. B. Piejak et al., Plasma Sources Sci. Technol. 1, 179 (1992)] when the absorbed power is maximized in an inductively coupled plasma. From the analysis of the transformer circuit model, the maximum power transfer conditions, which depend on the external discharge parameters and the internal plasma characteristics, were obtained. It was found that a maximum power transfer occurs when δ≈0.38R for the discharge condition at which ν{sub m}/ω≪1, while it occurs when δ≈√(2)√(ω/ν{sub m})R for the discharge condition at which ν{sub m}/ω≫1. The results of this circuit analysis are consistent with the stable last inductive mode region of an inductive-to-capacitive mode transition [Lee and Chung, Phys. Plasmas 13, 063510 (2006)], which was theoretically derived from Maxwell's equations. Our results were also in agreement with the experimental results. From this work, we demonstrate that a simple circuit analysis can be applied to explain complex physical phenomena to a certain extent.

  6. Phase 2 study of carfilzomib, thalidomide, and dexamethasone as induction/consolidation therapy for newly diagnosed multiple myeloma

    PubMed Central

    Asselbergs, Emilie; Zweegman, Sonja; van der Holt, Bronno; Kersten, Marie Jose; Vellenga, Edo; van Marwijk-Kooy, Marinus; Broyl, Annemiek; de Weerdt, Okke; Lonergan, Sarah; Palumbo, Antonio; Lokhorst, Henk

    2015-01-01

    This multicenter phase 2 study of the European Myeloma Network investigated the combination of carfilzomib, thalidomide, and dexamethasone (KTd) as induction/consolidation therapy for transplant-eligible patients with previously untreated multiple myeloma (N = 91). During KTd induction therapy, patients received 4 cycles of carfilzomib 20/27 mg/m2 (n = 50), 20/36 mg/m2 (n = 20), 20/45 mg/m2 (n = 21), or 20/56 mg/m2 (n = 20) on days 1, 2, 8, 9, 15, and 16 of a 28-day cycle; thalidomide 200 mg on days 1 to 28; and dexamethasone 20 mg on days 1, 2, 8, 9, 15, and 16. After autologous stem cell transplantation, patients proceeded to KTd consolidation therapy, where the target doses of carfilzomib were 27 mg/m2, 36 mg/m2, 45 mg/m2, or 56 mg/m2, respectively, and thalidomide 50 mg. Common grade 3/4 adverse events included respiratory (15%), gastrointestinal (12%), and skin disorders (10%); polyneuropathy was infrequent (1%). Complete response rates after induction and consolidation treatment were 25% and 63%, respectively; rates of very good partial response or better after induction and consolidation were 68% and 89%, respectively. At a median follow-up of 23 months, the 36-month progression-free survival rate was 72%. The KTd induction and consolidation regimens were active, safe, and well tolerated. This study was registered at http://www.trialregister.nl as #NTR2422. PMID:25398935

  7. Stroke during induction of labour in a patient with carotid aneurysm and prior multiple venous thromboses

    PubMed Central

    Datta, Sujata; Stern, Jeremy S; Williams, Bode

    2009-01-01

    A case of stroke during induction of labour in a pregnant patient at term anticoagulated for prior venous thrombosis is reported. The cause was a middle cerebral artery embolism, originating from a false dissecting aneurysm of the internal carotid artery. Investigations and causes of stroke in a pregnant patient are briefly outlined.

  8. Couple Coping and Adjustment to Multiple Sclerosis in Care Receiver-Carer Dyads.

    ERIC Educational Resources Information Center

    Pakenham, Kenneth I.

    1998-01-01

    The utility of "coping congruency" and "average level of couple coping" in explaining adjustment to multiple sclerosis was examined. Interview and questionnaire data was collected for 45 dyads with a 12-month follow-up. Predictors include Time 1 illness, caregiving, and coping variables. Findings support both concepts for explaining collective and…

  9. Measuring Inductive-Heating Coupling Coefficients and Thermal Loss Characteristics as a Function of Crucible Geometry and Material Selection

    NASA Astrophysics Data System (ADS)

    Gomes, Jay

    A power measurement system has been designed for an ultra-high temperature inductively heated molten oxide electrolysis (MOE) reactor. The work presented in this research contributes to three different aspects of the induction heated MOE reactor facility: mathematical modeling of coil-to-workpiece power transfer, numerical modeling of heat transfer within the reactor, and experiments to measure the total hemispherical emittance of potential crucible materials. Facility-specific coupling coefficients for various samples have been experimentally determined for the MOE reactor facility. An analytical model coupling the predicted power input with heat transfer software was developed using COMSOL Multiphysics, and validated with experimental measurements of the steady state temperature gradient inside the reactor. These models were used to support the design of an experiment to measure the total hemispherical emissivity (epsilon) of conductive samples using a transient calorimetric technique. Results of epsilon are presented over a wide range of temperatures for copper, nickel, graphite and molybdenum. Furthermore, an investigation into optimizing the reactor system for heating will be discussed.

  10. Calibration of laser ablation inductively coupled plasma mass spectrometry using dried solution aerosols for the quantitative analysis of solid samples

    SciTech Connect

    Leach, J.

    1999-02-12

    Inductively coupled plasma mass spectrometry (ICP-MS) has become the method of choice for elemental and isotopic analysis. Several factors contribute to its success. Modern instruments are capable of routine analysis at part per trillion levels with relative detection limits in part per quadrillion levels. Sensitivities in these instruments can be as high as 200 million counts per second per part per million with linear dynamic ranges up to eight orders of magnitude. With standards for only a few elements, rapid semiquantitative analysis of over 70 elements in an individual sample can be performed. Less than 20 years after its inception ICP-MS has shown to be applicable to several areas of science. These include geochemistry, the nuclear industry, environmental chemistry, clinical chemistry, the semiconductor industry, and forensic chemistry. In this introduction, the general attributes of ICP-MS will be discussed in terms of instrumentation and sample introduction. The advantages and disadvantages of current systems are presented. A detailed description of one method of sample introduction, laser ablation, is given. The paper also gives conclusions and suggestions for future work. Chapter 2, Quantitative analysis of solids by laser ablation inductively coupled plasma mass spectrometry using dried solution aerosols for calibration, has been removed for separate processing.

  11. Multi-elemental analysis of aqueous geochemical samples by quadrupole inductively coupled plasma-mass spectrometry (ICP-MS)

    USGS Publications Warehouse

    Wolf, Ruth E.; Adams, Monique

    2015-01-01

    Typically, quadrupole inductively coupled plasma-mass spectrometry (ICP-MS) is used to determine as many as 57 major, minor, and trace elements in aqueous geochemical samples, including natural surface water and groundwater, acid mine drainage water, and extracts or leachates from geological samples. The sample solution is aspirated into the inductively coupled plasma (ICP) which is an electrodeless discharge of ionized argon gas at a temperature of approximately 6,000 degrees Celsius. The elements in the sample solution are subsequently volatilized, atomized, and ionized by the ICP. The ions generated are then focused and introduced into a quadrupole mass filter which only allows one mass to reach the detector at a given moment in time. As the settings of the mass analyzer change, subsequent masses are allowed to impact the detector. Although the typical quadrupole ICP-MS system is a sequential scanning instrument (determining each mass separately), the scan speed of modern instruments is on the order of several thousand masses per second. Consequently, typical total sample analysis times of 2–3 minutes are readily achievable for up to 57 elements.

  12. Cobalamin speciation using reversed-phase micro-high-performance liquid chromatography interfaced to inductively coupled plasma mass spectrometry

    NASA Astrophysics Data System (ADS)

    Yanes, Enrique G.; Miller-Ihli, Nancy J.

    2004-06-01

    Micro-high-performance liquid chromatography interfaced to inductively coupled plasma mass spectrometry was optimized for the determination and separation of a mixture of cobalt containing species. Four cobalamin species (cyanocobalamin, hydroxocobalamin, methylcobalamin, and 5'-deoxyadenosylcobalamin) representing the various forms of vitamin B12 as well as the harmful corrinoid analogue cobinamide dicyanide were separated using reversed-phase microcapillary chromatography with columns containing C18 packing material with a 2-μm particle size. Selection of organic solvents for the separation took into consideration compatibility with the inductively coupled plasma mass spectrometer being used for element specific detection. Optimized method conditions included use of a methanol gradient and make-up solution for the nebulizer. Some issues associated with dead volume were overcome by the extension of the gradient program. The total analysis time was 52 min. The column-to-column variability was evaluated and was found to be very reasonable (9% RSD on average), confirming that this method is rugged and that the technology should be easily transferred to other laboratories.

  13. Comparative analysis of barium titanate thin films dry etching using inductively coupled plasmas by different fluorine-based mixture gas

    PubMed Central

    2014-01-01

    In this work, the inductively coupled plasma etching technique was applied to etch the barium titanate thin film. A comparative study of etch characteristics of the barium titanate thin film has been investigated in fluorine-based (CF4/O2, C4F8/O2 and SF6/O2) plasmas. The etch rates were measured using focused ion beam in order to ensure the accuracy of measurement. The surface morphology of etched barium titanate thin film was characterized by atomic force microscope. The chemical state of the etched surfaces was investigated by X-ray photoelectron spectroscopy. According to the experimental result, we monitored that a higher barium titanate thin film etch rate was achieved with SF6/O2 due to minimum amount of necessary ion energy and its higher volatility of etching byproducts as compared with CF4/O2 and C4F8/O2. Low-volatile C-F compound etching byproducts from C4F8/O2 were observed on the etched surface and resulted in the reduction of etch rate. As a result, the barium titanate films can be effectively etched by the plasma with the composition of SF6/O2, which has an etch rate of over than 46.7 nm/min at RF power/inductively coupled plasma (ICP) power of 150/1,000 W under gas pressure of 7.5 mTorr with a better surface morphology. PMID:25278821

  14. Determination of hexavalent chromium in traditional Chinese medicines by high-performance liquid chromatography with inductively coupled plasma mass spectrometry.

    PubMed

    Li, Peng; Li, Li-Min; Xia, Jing; Cao, Shuai; Hu, Xin; Lian, Hong-Zhen; Ji, Shen

    2015-12-01

    An analytical method that combined high-performance liquid chromatography with inductively coupled plasma mass spectrometry has been developed for the determination of hexavalent chromium in traditional Chinese medicines. Hexavalent chromium was extracted using the alkaline solution. The parameters such as the concentration of alkaline and the extraction temperature have been optimized to minimize the interconversion between trivalent chromium and hexavalent chromium. The extracted hexavalent chromium was separated on a weak anion exchange column in isocratic mode, followed by inductively coupled plasma mass spectrometry determination. To obtain a better chromatographic resolution and sensitivity, 75 mM NH4 NO3 at pH 7 was selected as the mobile phase. The linearity of the proposed method was investigated in the range of 0.2-5.0 μg L(-1) (r(2) = 0.9999) for hexavalent chromium. The limits of detection and quantitation are 0.1 and 0.3 μg L(-1) , respectively. The developed method was successfully applied to the determination of hexavalent chromium in Chloriti lapis and Lumbricus with satisfactory recoveries of 95.8-112.8%. PMID:26541101

  15. Controlled dissolution of silicon dioxide layers for depth resolved multielement analysis by inductively coupled plasma-mass spectrometry

    NASA Astrophysics Data System (ADS)

    Lorge, Susan E.; Houk, R. S.

    2009-11-01

    Dissolution procedures were developed to control the number of surface layers removed, in an attempt to achieve depth resolved analysis by inductively coupled plasma-mass spectrometry (ICP-MS). NIST 612 glass was chosen because it is a homogeneous material with many elements at interesting concentrations, ~ 50 ppm. Varying dissolution time and HF concentration resulted in the reproducible removal of SiO 2 layers as thin as 70 Å deep. Dissolved trace metals were determined after dilution by inductively coupled plasma-mass spectrometry (ICP-MS) with a magnetic sector instrument. The amount removed was determined from the concentration of a major element, Ca. With the exception of Zn, trace metal concentrations agreed reasonably well with their certified values for removal depths of 500, 300 and 150 Å. Zinc concentration was significantly high in all dissolutions indicating either a contamination problem or that Zn is removed at a faster rate than Ca. For the dissolutions that removed 70 Å of SiO 2, Cr, Mn, Co, Sr, Cd, Ce, Dy, Er, Yb and U recovery results agreed with their certified values (~ 50 ppm); Ti, As, Mo, Ba, and Th could not be determined because net intensities were below 3 σ of the blank; and measured concentrations for Cu, Pb and Zn were well above the certified values.

  16. Inductive coupling links for lowest misalignment effects in transcutaneous implanted devices.

    PubMed

    Abbas, Saad Mutashar; Hannan, Mahammad A; Samad, Salina A; Hussain, Aini

    2014-06-01

    Use of transcutaneous inductive links is a widely known method for the wireless powering of bio-implanted devices such as implanted microsystems. The design of the coil for inductive links is generally not optimal. In this study, inductive links were used on the basis of the small loop antenna theory to reduce the effects of lateral coil misalignments on the biological human tissue model at 13.56 MHz. The tissue, which measures 60 mm×70 mm×5 mm, separates the reader and the implanted coils. The aligned coils and the lateral misalignment coils were investigated in different parametric x-distance misalignments. The optimal coil layout was developed on the basis of the layout rules presented in previous studies. Results show that the gain around the coils, which were separated by wet and dry skin, was constant and confirmed the omnidirectional radiation pattern even though the lateral misalignment between coils was smaller or greater than the implanted coil radius. This misalignment can be <4 mm or >6 mm up to 8 mm. Moreover, coil misalignments and skin condition do not affect the efficient performance of the coil. PMID:24445231

  17. Investigations into the origins of polyatomic ions in inductively coupled plasma-mass spectrometry

    SciTech Connect

    McIntyre, Sally M.

    2010-01-01

    An inductively coupled plasma-mass spectrometer (ICP-MS) is an elemental analytical instrument capable of determining nearly all elements in the periodic table at limits of detection in the parts per quadrillion and with a linear analytical range over 8-10 orders of magnitude. Three concentric quartz tubes make up the plasma torch. Argon gas is spiraled through the outer tube and generates the plasma powered by a looped load coil operating at 27.1 or 40.6 MHz. The argon flow of the middle channel is used to keep the plasma above the innermost tube through which solid or aqueous sample is carried in a third argon stream. A sample is progressively desolvated, atomized and ionized. The torch is operated at atmospheric pressure. To reach the reduced pressures of mass spectrometers, ions are extracted through a series of two, approximately one millimeter wide, circular apertures set in water cooled metal cones. The space between the cones is evacuated to approximately one torr. The space behind the second cone is pumped down to, or near to, the pressure needed for the mass spectrometer (MS). The first cone, called the sampler, is placed directly in the plasma plume and its position is adjusted to the point where atomic ions are most abundant. The hot plasma gas expands through the sampler orifice and in this expansion is placed the second cone, called the skimmer. After the skimmer traditional MS designs are employed, i.e. quadrupoles, magnetic sectors, time-of-flight. ICP-MS is the leading trace element analysis technique. One of its weaknesses are polyatomic ions. This dissertation has added to the fundamental understanding of some of these polyatomic ions, their origins and behavior. Although mainly continuing the work of others, certain novel approaches have been introduced here. Chapter 2 includes the first reported efforts to include high temperature corrections to the partition functions of the polyatomic ions in ICP-MS. This and other objections to preceeding

  18. Axially and radially viewed inductively coupled plasmas — a critical review

    NASA Astrophysics Data System (ADS)

    Brenner, I. B.; Zander, A. T.

    2000-08-01

    The present status of axially viewed inductively coupled plasmas (ICP) is reviewed with special emphasis placed on the analytical performance of currently available systems. Descriptions are given of the various designs of the plasma-spectrometer configuration. Conventional figures of merit such as limits of detection, background behavior, interferences due to easily ionized elements (EIE), Ca and acids, and the Mg II 280.270 nm/Mg I 285.213 nm intensity ratio, are used to compare the performance of axially viewed and radially viewed ICPs. Various modes of sample introduction, including conventional pneumatic and ultrasonic nebulization (USN), thermospray and a direct injection probe will be described. For axially viewed ICPs, limits of detection (LOD) are improved by factors varying from approximately 2 to 30. Additional improvements by factors of 2-20 can be obtained using USN. The improvement factors generally depend on energy potentials of the spectral lines and the element. Although limits of detection in the presence of Ca and Na are degraded relative to an aqueous solution 10-30-fold, USN LODs using an axially viewed ICP are improved relative to those obtained using a pneumatic nebulizer for solutions containing Ca and Na. With normal aerosol load and under robust plasma conditions (as evidenced by Mg II/Mg I intensity ratios >8), EIE, Ca and mineral acid induced interferences are relatively small and are similar in axial and conventional radial configurations. However, interferences due to Ca are larger than those caused by Na due to the larger amount of energy required to dissociate the matrix. Matrix effects increase considerably when an USN is employed. For robust plasmas, ICP operating conditions and performance for multi-element quantitative analysis do not differ significantly from those of conventional radial configurations. In cases where robustness decreases, matrix interferences should be taken into account when establishing optimum conditions for

  19. Axially and radially viewed inductively coupled plasmas — a critical review

    NASA Astrophysics Data System (ADS)

    Brenner, I. B.; Zander, A. T.

    2000-08-01

    The present status of axially viewed inductively coupled plasmas (ICP) is reviewed with special emphasis placed on the analytical performance of currently available systems. Descriptions are given of the various designs of the plasma-spectrometer configuration. Conventional figures of merit such as limits of detection, background behavior, interferences due to easily ionized elements (EIE), Ca and acids, and the Mg II 280.270 nm/Mg I 285.213 nm intensity ratio, are used to compare the performance of axially viewed and radially viewed ICPs. Various modes of sample introduction, including conventional pneumatic and ultrasonic nebulization (USN), thermospray and a direct injection probe will be described. For axially viewed ICPs, limits of detection (LOD) are improved by factors varying from approximately 2 to 30. Additional improvements by factors of 2-20 can be obtained using USN. The improvement factors generally depend on energy potentials of the spectral lines and the element. Although limits of detection in the presence of Ca and Na are degraded relative to an aqueous solution 10-30-fold, USN LODs using an axially viewed ICP are improved relative to those obtained using a pneumatic nebulizer for solutions containing Ca and Na. With normal aerosol load and under robust plasma conditions (as evidenced by Mg II/Mg I intensity ratios >8), EIE, Ca and mineral acid induced interferences are relatively small and are similar in axial and conventional radial configurations. However, interferences due to Ca are larger than those caused by Na due to the larger amount of energy required to dissociate the matrix. Matrix effects increase considerably when an USN is employed. For robust plasmas, ICP operating conditions and performance for multi-element quantitative analysis do not differ significantly from those of conventional radial configurations. In cases where robustness decreases, matrix interferences should be taken into account when establishing optimum conditions for

  20. Establishment of In Silico Prediction Models for CYP3A4 and CYP2B6 Induction in Human Hepatocytes by Multiple Regression Analysis Using Azole Compounds.

    PubMed

    Nagai, Mika; Konno, Yoshihiro; Satsukawa, Masahiro; Yamashita, Shinji; Yoshinari, Kouichi

    2016-08-01

    Drug-drug interactions (DDIs) via cytochrome P450 (P450) induction are one clinical problem leading to increased risk of adverse effects and the need for dosage adjustments and additional therapeutic monitoring. In silico models for predicting P450 induction are useful for avoiding DDI risk. In this study, we have established regression models for CYP3A4 and CYP2B6 induction in human hepatocytes using several physicochemical parameters for a set of azole compounds with different P450 induction as characteristics as model compounds. To obtain a well-correlated regression model, the compounds for CYP3A4 or CYP2B6 induction were independently selected from the tested azole compounds using principal component analysis with fold-induction data. Both of the multiple linear regression models obtained for CYP3A4 and CYP2B6 induction are represented by different sets of physicochemical parameters. The adjusted coefficients of determination for these models were of 0.8 and 0.9, respectively. The fold-induction of the validation compounds, another set of 12 azole-containing compounds, were predicted within twofold limits for both CYP3A4 and CYP2B6. The concordance for the prediction of CYP3A4 induction was 87% with another validation set, 23 marketed drugs. However, the prediction of CYP2B6 induction tended to be overestimated for these marketed drugs. The regression models show that lipophilicity mostly contributes to CYP3A4 induction, whereas not only the lipophilicity but also the molecular polarity is important for CYP2B6 induction. Our regression models, especially that for CYP3A4 induction, might provide useful methods to avoid potent CYP3A4 or CYP2B6 inducers during the lead optimization stage without performing induction assays in human hepatocytes. PMID:27208383

  1. Bacillus cereus bacteremia and multiple brain abscesses during acute lymphoblastic leukemia induction therapy.

    PubMed

    Hansford, Jordan R; Phillips, Marianne; Cole, Catherine; Francis, Joshua; Blyth, Christopher C; Gottardo, Nicholas G

    2014-04-01

    Bacillus cereus can cause serious infections in immunosuppressed patients. This population may be susceptible to B. cereus pneumonia, bacteremia, cellulitis, and rarely cerebral abscess. Here we report an 8-year-old boy undergoing induction therapy for acute lymphoblastic leukemia who developed multifocal B. cereus cerebral abscesses, highlighting the propensity for B. cereus to develop cerebral abscesses. A review of the literature over the past 25 years identified another 11 cases (3 children and 8 adults) of B. cereus cerebral abscess in patients undergoing cancer therapy. B. cereus cerebral abscesses were associated with a high mortality rate (42%) and significant morbidity. Notably, B. cereus bacteremia with concomitant cerebral abscess was associated with induction chemotherapy for acute leukemia in both children and adults (10 of 12 case reports). Our case report and review of the literature highlights the propensity for B. cereus to develop cerebral abscess(es). Therefore, early consideration for neuroimaging should be given for any neutropenic cancer patient identified with B. cereus bacteremia, in particular those with acute leukemia during induction therapy. PMID:23619116

  2. Fibroblast growth factor signalling in multiple sclerosis: inhibition of myelination and induction of pro-inflammatory environment by FGF9.

    PubMed

    Lindner, Maren; Thümmler, Katja; Arthur, Ariel; Brunner, Sarah; Elliott, Christina; McElroy, Daniel; Mohan, Hema; Williams, Anna; Edgar, Julia M; Schuh, Cornelia; Stadelmann, Christine; Barnett, Susan C; Lassmann, Hans; Mücklisch, Steve; Mudaliar, Manikhandan; Schaeren-Wiemers, Nicole; Meinl, Edgar; Linington, Christopher

    2015-07-01

    Remyelination failure plays an important role in the pathophysiology of multiple sclerosis, but the underlying cellular and molecular mechanisms remain poorly understood. We now report actively demyelinating lesions in patients with multiple sclerosis are associated with increased glial expression of fibroblast growth factor 9 (FGF9), which we demonstrate inhibits myelination and remyelination in vitro. This inhibitory activity is associated with the appearance of multi-branched 'pre-myelinating' MBP+ / PLP+ oligodendrocytes that interact with axons but fail to assemble myelin sheaths; an oligodendrocyte phenotype described previously in chronically demyelinated multiple sclerosis lesions. This inhibitory activity is not due to a direct effect of FGF9 on cells of the oligodendrocyte lineage but is mediated by factors secreted by astrocytes. Transcriptional profiling and functional validation studies demonstrate that these include effects dependent on increased expression of tissue inhibitor of metalloproteinase-sensitive proteases, enzymes more commonly associated with extracellular matrix remodelling. Further, we found that FGF9 induces expression of Ccl2 and Ccl7, two pro-inflammatory chemokines that contribute to recruitment of microglia and macrophages into multiple sclerosis lesions. These data indicate glial expression of FGF9 can initiate a complex astrocyte-dependent response that contributes to two distinct pathogenic pathways involved in the development of multiple sclerosis lesions. Namely, induction of a pro-inflammatory environment and failure of remyelination; a combination of effects predicted to exacerbate axonal injury and loss in patients. PMID:25907862

  3. Crosstalk-insensitive method for simultaneously coupling multiple pairs of resonators

    NASA Astrophysics Data System (ADS)

    Yang, Chui-Ping; Su, Qi-Ping; Zheng, Shi-Biao; Nori, Franco

    2016-04-01

    In a circuit consisting of two or more resonators, the intercavity crosstalk is inevitable, which could create some problems, such as degrading the performance of quantum operations and the fidelity of various quantum states. The focus of this work is to propose a crosstalk-insensitive method for simultaneously coupling multiple pairs of resonators, which is important in large-scale quantum information processing and communication in a network consisting of resonators or cavities. In this work, we consider 2 N resonators of different frequencies, which are coupled to a three-level quantum system (qutrit). By applying a strong pulse to the coupler qutrit, we show that an effective Hamiltonian can be constructed for simultaneously coupling multiple pairs of resonators. The main advantage of this proposal is that the effect of inter-resonator crosstalks is greatly suppressed by using resonators of different frequencies. In addition, by employing the qutrit-resonator dispersive interaction, the intermediate higher-energy level of the qutrit is virtually excited and thus decoherence from this level is suppressed. This effective Hamiltonian can be applied to implement quantum operations with photonic qubits distributed in different resonators. As one application of this Hamiltonian, we show how to simultaneously generate multiple Einstein-Podolsky-Rosen pairs of photonic qubits distributed in 2 N resonators. Numerical simulations show that it is feasible to prepare two high-fidelity EPR photonic pairs using a setup of four one-dimensional transmission line resonators coupled to a superconducting flux qutrit with current circuit QED technology.

  4. Mean deviation coupling synchronous control for multiple motors via second-order adaptive sliding mode control.

    PubMed

    Li, Lebao; Sun, Lingling; Zhang, Shengzhou

    2016-05-01

    A new mean deviation coupling synchronization control strategy is developed for multiple motor control systems, which can guarantee the synchronization performance of multiple motor control systems and reduce complexity of the control structure with the increasing number of motors. The mean deviation coupling synchronization control architecture combining second-order adaptive sliding mode control (SOASMC) approach is proposed, which can improve synchronization control precision of multiple motor control systems and make speed tracking errors, mean speed errors of each motor and speed synchronization errors converge to zero rapidly. The proposed control scheme is robustness to parameter variations and random external disturbances and can alleviate the chattering phenomena. Moreover, an adaptive law is employed to estimate the unknown bound of uncertainty, which is obtained in the sense of Lyapunov stability theorem to minimize the control effort. Performance comparisons with master-slave control, relative coupling control, ring coupling control, conventional PI control and SMC are investigated on a four-motor synchronization control system. Extensive comparative results are given to shown the good performance of the proposed control scheme. PMID:26899554

  5. Use of a parallel path nebulizer for capillary-based microseparation techniques coupled with an inductively coupled plasma mass spectrometer for speciation measurements

    NASA Astrophysics Data System (ADS)

    Yanes, Enrique G.; Miller-Ihli, Nancy J.

    2004-06-01

    A low flow, parallel path Mira Mist CE nebulizer designed for capillary electrophoresis (CE) was evaluated as a function of make-up solution flow rate, composition, and concentration, as well as the nebulizer gas flow rate. This research was conducted in support of a project related to the separation and quantification of cobalamin (vitamin B-12) species using microseparation techniques combined with inductively coupled plasma mass spectrometry (ICP-MS) detection. As such, Co signals were monitored during the nebulizer characterization process. Transient effects in the ICP were studied to evaluate the suitability of using gradients for microseparations and the benefit of using methanol for the make-up solution was demonstrated. Co signal response changed significantly as a function of changing methanol concentrations of the make-up solution and maximum signal enhancement was seen at 20% methanol with a 15 μl/min flow rate. Evaluation of the effect of changing the nebulizer gas flow rates showed that argon flows from 0.8 to 1.2 l/min were equally effective. The Mira Mist CE parallel path nebulizer was then evaluated for interfacing capillary microseparation techniques including capillary electrophoresis (CE) and micro high performance liquid chromatography (μHPLC) to inductively coupled plasma mass spectrometry (ICP-MS). A mixture of four cobalamin species standards (cyanocobalamin, hydroxocobalamin, methylcobalamin, and 5' deoxyadenosylcobalamin) and the corrinoid analogue cobinamide dicyanide were successfully separated using both CE-ICP-MS and μHPLC-ICP-MS using the parallel path nebulizer with a make-up solution containing 20% methanol with a flow rate of 15 μl/min.

  6. Bayesian characterization of multiple-slope sound energy decays in coupled-volume systems.

    PubMed

    Xiang, Ning; Goggans, Paul; Jasa, Tomislav; Robinson, Philip

    2011-02-01

    Due to recent developments in concert hall design, there is an increasing interest in the analysis of sound energy decays consisting of multiple exponential decay rates. It has been considered challenging to estimate parameters associated with double-rate (slope) decay characteristics, and even more challenging when the coupled-volume systems contain more than two decay processes. To meet the need of characterizing energy decays of multiple decay processes, this work investigates coupled-volume systems using acoustic scale-models of three coupled rooms. Two Bayesian formulations are compared using the experimentally measured sound energy decay data. A fully parameterized Bayesian formulation has been found to be capable of characterization of multiple-slope decays beyond the single-slope and double-slope energy decays. Within the Bayesian framework using this fully parameterized formulation, an in-depth analysis of likelihood distributions over multiple-dimensional decay parameter space motivates the use of Bayesian information criterion, an efficient approach to solving Bayesian model selection problems that are suitable for estimating the number of exponential decays. The analysis methods are then applied to a geometric-acoustics simulation of a conceptual concert hall. Sound energy decays more complicated than single-slope and double-slope nature, such as triple-slope decays have been identified and characterized. PMID:21361433

  7. Rapid identification and analysis of airborne plutonium using a combination of alpha spectroscopy and inductively coupled plasma mass spectrometry.

    PubMed

    Farmer, Dennis E; Steed, Amber C; Sobus, Jon; Stetzenbach, Klaus; Lindley, Kaz; Hodge, Vernon F

    2003-10-01

    Recent wildland fires near two U.S. nuclear facilities point to a need to rapidly identify the presence of airborne plutonium during incidents involving the potential release of radioactive materials. Laboratory turn-around times also need to be shortened for critical samples collected in the earliest stages of radiological emergencies. This note discusses preliminary investigations designed to address both these problems. The methods under review are same day high-resolution alpha spectroscopy to screen air filter samples for the presence of plutonium and inductively coupled plasma mass spectrometry to perform sensitive plutonium analyses. Thus far, using modified alpha spectroscopy techniques, it has been possible to reliably identify the approximately 5.2 MeV emission of 239Pu on surrogate samples (air filters artificially spiked with plutonium after collection) even though the primary alpha-particle emissions of plutonium are, as expected, superimposed against a natural alpha radiation background dominated by short-lived radon and thoron progeny (approximately 6-9 MeV). Several processing methods were tested to prepare samples for analysis and shorten laboratory turn-around time. The most promising technique was acid-leaching of air filter samples using a commercial open-vessel microwave digestion system. Samples prepared in this way were analyzed by both alpha spectroscopy (as a thin-layer iron hydroxide co-precipitate) and inductively coupled plasma mass spectrometry. The detection levels achieved for 239Pu--approximately 1 mBq m(-3) for alpha spectroscopy screening, and, < 0.1 mBq m(-3) for inductively coupled plasma mass spectrometry analysis--are consistent with derived emergency response levels based on EPA's Protective Action Guides, and samples can be evaluated in 36 to 72 h. Further, if samples can be returned to a fixed-laboratory and processed immediately, results from mass spectrometry could be available in as little as 24 h. When fully implemented

  8. Modelling of the evaporation behaviour of particulate material for slurry nebulization inductively coupled plasma atomic emission spectrometry

    NASA Astrophysics Data System (ADS)

    Merten, D.; Heitland, P.; Broekaert, J. A. C.

    1997-11-01

    This paper is an electronic publication in Spectrochimica Acta Electronica (SAE), the electronic section of Spectrochimica Acta, Part B (SAB). This hardcopy text, comprising the main body and an appendix, is accompanied by a disk with programs, data files and a brief manual. The main body discusses purpose, design principle and usage of the computer software for modelling the evaporation behaviour of particles in inductively coupled plasma atomic emission spectrometry (ICP-AES). Computer software has been developed in FORTRAN 77 language in order to simulate the evaporation behaviour of particles of refractory materials such as encountered in the analysis of advanced ceramic powders by slurry nebulization inductively coupled argon plasma atomic spectrometry. The program simulates the evaporation of single particles in the inductively coupled plasma and also enable it to calculate on the base of a given particle size distribution the evaporation behaviour of all the particles contained in a sample. In a so-called "intensity concept", the intensity is calculated as a function of the observation height in order to determine recovery rates for slurries compared with aqueous solutions. This yields a quick insight whether a calibration with aqueous solutions can be used for analysis of slurries of a given powder by slurry nebulization ICP-AES and also is a help in determining the optimal parameters for analyses of powders by means of slurry nebulization ICP-AES. Applications for the evaporation of Al 2O 3 and SiC powders document the usefulness of the model for the case of a 1.5 kW argon ICP of which the temperature at 8 mm above the load coil has been determined to be 6100 K. The model predicts the maximum particle size for SiC and Al 2O 3 that can be transported (10-15 μm) and evaporated for a given efficiency under given experimental conditions. For both Al 2O 3 and SiC, two ceramic powders of different grain size were investigated. The median particle sizes cover

  9. Development of Desolvation System for Single-cell Analysis Using Droplet Injection Inductively Coupled Plasma Atomic Emission Spectroscopy.

    PubMed

    Ishihara, Yukiko; Aida, Mari; Nomura, Akito; Miyahara, Hidekazu; Hokura, Akiko; Okino, Akitoshi

    2015-01-01

    With a view to enhance the sensitivity of analytical instruments used in the measurement of trace elements contained in a single cell, we have now equipped the previously reported micro-droplet injection system (M-DIS) with a desolvation system. This modified M-DIS was coupled to inductively coupled plasma atomic emission spectroscopy (ICP-AES) and evaluated for its ability to measure trace elements. A flow rate of 100 mL/min for the additional gas and a measurement point -7.5 mm above the load coil (ALC) have been determined to be the optimal parameters for recording the emission intensity of the Ca(II) spectral lines. To evaluate the influence of the desolvation system, we recorded the emission intensities of the Ca(I), Ca(II), and H-β spectral lines with and without inclusion of the desolvation system. The emission intensity of the H-β spectral line reduces and the magnitude of the Ca(II)/Ca(I) emission intensity ratio increases four-fold with inclusion of the desolvation system. Finally, the elements Ca, Mg, and Fe present in a single cell of Pseudococcomyxa simplex are simultaneously determined by coupling the M-DIS equipped with the desolvation system to ICP-AES. PMID:26256601

  10. Battery-powered pulsed high density inductively coupled plasma source for pre-ionization in laboratory astrophysics experiments.

    PubMed

    Chaplin, Vernon H; Bellan, Paul M

    2015-07-01

    An electrically floating radiofrequency (RF) pre-ionization plasma source has been developed to enable neutral gas breakdown at lower pressures and to access new experimental regimes in the Caltech laboratory astrophysics experiments. The source uses a customized 13.56 MHz class D RF power amplifier that is powered by AA batteries, allowing it to safely float at 3-6 kV with the electrodes of the high voltage pulsed power experiments. The amplifier, which is capable of 3 kW output power in pulsed (<1 ms) operation, couples electrical energy to the plasma through an antenna external to the 1.1 cm radius discharge tube. By comparing the predictions of a global equilibrium discharge model with the measured scalings of plasma density with RF power input and axial magnetic field strength, we demonstrate that inductive coupling (rather than capacitive coupling or wave damping) is the dominant energy transfer mechanism. Peak ion densities exceeding 5 × 10(19) m(-3) in argon gas at 30 mTorr have been achieved with and without a background field. Installation of the pre-ionization source on a magnetohydrodynamically driven jet experiment reduced the breakdown time and jitter and allowed for the creation of hotter, faster argon plasma jets than was previously possible. PMID:26233382

  11. Mass cytometry: technique for real time single cell multitarget immunoassay based on inductively coupled plasma time-of-flight mass spectrometry.

    PubMed

    Bandura, Dmitry R; Baranov, Vladimir I; Ornatsky, Olga I; Antonov, Alexei; Kinach, Robert; Lou, Xudong; Pavlov, Serguei; Vorobiev, Sergey; Dick, John E; Tanner, Scott D

    2009-08-15

    A novel instrument for real time analysis of individual biological cells or other microparticles is described. The instrument is based on inductively coupled plasma time-of-flight mass spectrometry and comprises a three-aperture plasma-vacuum interface, a dc quadrupole turning optics for decoupling ions from neutral components, an rf quadrupole ion guide discriminating against low-mass dominant plasma ions, a point-to-parallel focusing dc quadrupole doublet, an orthogonal acceleration reflectron analyzer, a discrete dynode fast ion detector, and an 8-bit 1 GHz digitizer. A high spectrum generation frequency of 76.8 kHz provides capability for collecting multiple spectra from each particle-induced transient ion cloud, typically of 200-300 micros duration. It is shown that the transients can be resolved and characterized individually at a peak frequency of 1100 particles per second. Design considerations and optimization data are presented. The figures of merit of the instrument are measured under standard inductively coupled plasma (ICP) operating conditions (<3% cerium oxide ratio). At mass resolution (full width at half-maximum) M/DeltaM > 900 for m/z = 159, the sensitivity with a standard sample introduction system of >1.4 x 10(8) ion counts per second per mg L(-1) of Tb and an abundance sensitivity of (6 x 10(-4))-(1.4 x 10(-3)) (trailing and leading masses, respectively) are shown. The mass range (m/z = 125-215) and abundance sensitivity are sufficient for elemental immunoassay with up to 60 distinct available elemental tags. When <15 elemental tags are used, a higher sensitivity mode at lower resolution (M/DeltaM > 500) can be used, which provides >2.4 x 10(8) cps per mg L(-1) of Tb, at (1.5 x 10(-3))-(5.0 x 10(-3)) abundance sensitivity. The real-time simultaneous detection of multiple isotopes from individual 1.8 microm polystyrene beads labeled with lanthanides is shown. A real time single cell 20 antigen expression assay of model cell lines and leukemia

  12. Theory of the stationary macroscopic quantum behavior of inductively coupled superconducting weak links

    SciTech Connect

    Brunk, G.; Luebbig, H.

    1982-04-01

    A theory of the stationary response of a flux-controlled superconducting weak link is presented in the framework of reversible thermodynamics. The superconducting loop containing the weak line (SQUID): considered as a ''black box'': can be characterized by a nonlinear inductance L/sub s/ which uniquely describes the constitutive properties of the macroscopic quantum system. The influence of the temperature-dependent (nonsinusoidal) current-phase relation (CPR) on L/sub s/ and on the stability of the SQUID when operated in th nonhysteretic mode is analyzed taking into account the full nonlinearity of the CPR. The model presented enables a rigorous circuit analysis, even in the case of a nonlinear flux transformer.

  13. Analysis of energy harvesting from multiple pendulums with and without mechanical coupling

    NASA Astrophysics Data System (ADS)

    Malaji, P. V.; Ali, S. F.

    2015-11-01

    Multiple energy harvesters in a single device has become important to harvest enough power for sensors. In such situation presence of mistuning may change the performance of the overall system. This paper studies the issue of presence of mistuning in such system and also extend the study to performance evaluation when mechanically coupling is present between the multiple harvesters. A simple case of two pendulums in a same frame is analysed for electromagnetic energy harvesting. Experiments are carried out to support the numerical evaluation. The study limits its observations to low frequency and low amplitude motions. The observation made are very interesting and intricate.

  14. Real-time control of ion density and ion energy in chlorine inductively coupled plasma etch processing

    NASA Astrophysics Data System (ADS)

    Chang, Cheng-Hung; Leou, Keh-Chyang; Lin, Chaung; Lin, Tsan-Lang; Tseng, Chih-Wei; Tsai, Chuen-Horng

    2003-07-01

    In this study, we have experimentally demonstrated the real-time closed-loop control of both ion density and ion energy in a chlorine inductively coupled plasma etcher. To measure positive ion density, the trace rare gases-optical emission spectroscopy is used to measure the chlorine positive ion density. An rf voltage probe is adopted to measure the root-mean-square rf voltage on the electrostatic chuck which is linearly dependent on sheath voltage. One actuator is a 13.56 MHz rf generator to drive the inductive coil seated on a ceramic window. The second actuator is also a 13.56 MHz rf generator to power the electrostatic chuck. The closed-loop controller is designed to compensate for process drift, process disturbance, and pilot wafer effect and to minimize steady-state error of plasma parameters. This controller has been used to control the etch process of unpatterned polysilicon. The experimental results showed that the closed-loop control had a better repeatability of plasma parameters compared with open-loop control. The closed-loop control can eliminate the process disturbance resulting from reflected power. In addition, experimental results also demonstrated that closed-loop control has a better reproducibility in etch rate as compared with open-loop control.

  15. Analysis and Optimization of Spiral Circular Inductive Coupling Link for Bio-Implanted Applications on Air and within Human Tissue

    PubMed Central

    Mutashar, Saad; Hannan, Mahammad A.; Samad, Salina A.; Hussain, Aini

    2014-01-01

    The use of wireless communication using inductive links to transfer data and power to implantable microsystems to stimulate and monitor nerves and muscles is increasing. This paper deals with the development of the theoretical analysis and optimization of an inductive link based on coupling and on spiral circular coil geometry. The coil dimensions offer 22 mm of mutual distance in air. However, at 6 mm of distance, the coils offer a power transmission efficiency of 80% in the optimum case and 73% in the worst case via low input impedance, whereas, transmission efficiency is 45% and 32%, respectively, via high input impedance. The simulations were performed in air and with two types of simulated human biological tissues such as dry and wet-skin using a depth of 6 mm. The performance results expound that the combined magnitude of the electric field components surrounding the external coil is approximately 98% of that in air, and for an internal coil, it is approximately 50%, respectively. It can be seen that the gain surrounding coils is almost constant and confirms the omnidirectional pattern associated with such loop antennas which reduces the effect of non-alignment between the two coils. The results also show that the specific absorption rate (SAR) and power loss within the tissue are lower than that of the standard level. Thus, the tissue will not be damaged anymore. PMID:24984057

  16. Analysis and optimization of spiral circular inductive coupling link for bio-implanted applications on air and within human tissue.

    PubMed

    Mutashar, Saad; Hannan, Mahammad A; Samad, Salina A; Hussain, Aini

    2014-01-01

    The use of wireless communication using inductive links to transfer data and power to implantable microsystems to stimulate and monitor nerves and muscles is increasing. This paper deals with the development of the theoretical analysis and optimization of an inductive link based on coupling and on spiral circular coil geometry. The coil dimensions offer 22 mm of mutual distance in air. However, at 6 mm of distance, the coils offer a power transmission efficiency of 80% in the optimum case and 73% in the worst case via low input impedance, whereas, transmission efficiency is 45% and 32%, respectively, via high input impedance. The simulations were performed in air and with two types of simulated human biological tissues such as dry and wet-skin using a depth of 6 mm. The performance results expound that the combined magnitude of the electric field components surrounding the external coil is approximately 98% of that in air, and for an internal coil, it is approximately 50%, respectively. It can be seen that the gain surrounding coils is almost constant and confirms the omnidirectional pattern associated with such loop antennas which reduces the effect of non-alignment between the two coils. The results also show that the specific absorption rate (SAR) and power loss within the tissue are lower than that of the standard level. Thus, the tissue will not be damaged anymore. PMID:24984057

  17. Bulk plasma fragmentation in a C{sub 4}F{sub 8} inductively coupled plasma: A hybrid modeling study

    SciTech Connect

    Zhao, Shu-Xia; Zhang, Yu-Ru; Gao, Fei; Wang, You-Nian; Bogaerts, Annemie

    2015-06-28

    A hybrid model is used to investigate the fragmentation of C{sub 4}F{sub 8} inductive discharges. Indeed, the resulting reactive species are crucial for the optimization of the Si-based etching process, since they determine the mechanisms of fluorination, polymerization, and sputtering. In this paper, we present the dissociation degree, the density ratio of F vs. C{sub x}F{sub y} (i.e., fluorocarbon (fc) neutrals), the neutral vs. positive ion density ratio, details on the neutral and ion components, and fractions of various fc neutrals (or ions) in the total fc neutral (or ion) density in a C{sub 4}F{sub 8} inductively coupled plasma source, as well as the effect of pressure and power on these results. To analyze the fragmentation behavior, the electron density and temperature and electron energy probability function (EEPF) are investigated. Moreover, the main electron-impact generation sources for all considered neutrals and ions are determined from the complicated C{sub 4}F{sub 8} reaction set used in the model. The C{sub 4}F{sub 8} plasma fragmentation is explained, taking into account many factors, such as the EEPF characteristics, the dominance of primary and secondary processes, and the thresholds of dissociation and ionization. The simulation results are compared with experiments from literature, and reasonable agreement is obtained. Some discrepancies are observed, which can probably be attributed to the simplified polymer surface kinetics assumed in the model.

  18. Multielemental analysis of prehistoric animal teeth by laser-induced breakdown spectroscopy and laser ablation inductively coupled plasma mass spectrometry

    SciTech Connect

    Galiova, Michaela; Kaiser, Jozef; Fortes, Francisco J.; Novotny, Karel; Malina, Radomir; Prokes, Lubomir; Hrdlicka, Ales; Vaculovic, Tomas; Nyvltova Fisakova, Miriam; Svoboda, Jiri; Kanicky, Viktor; Laserna, Javier J.

    2010-05-01

    Laser-induced breakdown spectroscopy (LIBS) and laser ablation (LA) inductively coupled plasma (ICP) mass spectrometry (MS) were utilized for microspatial analyses of a prehistoric bear (Ursus arctos) tooth dentine. The distribution of selected trace elements (Sr, Ba, Fe) was measured on a 26 mmx15 mm large and 3 mm thick transverse cross section of a canine tooth. The Na and Mg content together with the distribution of matrix elements (Ca, P) was also monitored within this area. The depth of the LIBS craters was measured with an optical profilometer. As shown, both LIBS and LA-ICP-MS can be successfully used for the fast, spatially resolved analysis of prehistoric teeth samples. In addition to microchemical analysis, the sample hardness was calculated using LIBS plasma ionic-to-atomic line intensity ratios of Mg (or Ca). To validate the sample hardness calculations, the hardness was also measured with a Vickers microhardness tester.

  19. Plasma sterilization of Geobacillus Stearothermophilus by O{mathsf2}:N{mathsf2} RF inductively coupled plasma

    NASA Astrophysics Data System (ADS)

    Kylián, O.; Sasaki, T.; Rossi, F.

    2006-05-01

    The aim of this work is to identify the main process responsible for sterilization of Geobacillus Stearothermophilus spores in O{2}:N{2} RF inductively coupled plasma. In order to meet this objective the sterilization efficiencies of discharges in mixtures differing in the initial O{2}/N{2} ratios are compared with plasma properties and with scanning electron microscopy images of treated spores. According to the obtained results it can be concluded that under our experimental conditions the time needed to reach complete sterilization is more related to O atom density than UV radiation intensity, i.e. complete sterilization is not related only to DNA damage as in UV sterilization but more likely to the etching of the spore.

  20. Inductively Coupled Plasma/Mass Spectrometric Isotopic Determination of Nuclear Wastes Sources Associated with Hanford Tank Leaks

    SciTech Connect

    Evans, John C.; Dresel, P. Evan; Farmer, Orville T.

    2007-11-01

    The subsurface distribution of a nuclear waste tank leak on the U.S. Department of Energy’s Hanford Site was sampled by slant drilling techniques in order to characterize the chemical and radiological characteristics of the leaked material and assess geochemical transport properties of hazardous constituents. Sediment core samples recovered from the borehole were subjected to distilled water and acid leaching procedures with the resulting leachates analyzed for isotopic and chemical signatures. High-sensitivity inductively coupled plasma/mass spectrometry (ICP/MS) techniques were used for determination of isotopic ratios for Cs, I, Mo. Analysis of the isotopic patterns of I and Mo combined with associated chemical data showed evidence for at least two separate intrusions of nuclear waste into the subsurface. Isotopic data for Cs was inconclusive with respect to a source attribution signature.