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Note: This page contains sample records for the topic "accelerator mass spectrometry" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
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We encourage you to perform a real-time search of NLEBeta
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1

Symposium on accelerator mass spectrometry  

SciTech Connect

The area of accelerator mass spectrometry has expanded considerably over the past few years and established itself as an independent and interdisciplinary research field. Three years have passed since the first meeting was held at Rochester. A Symposium on Accelerator Mass Spectrometry was held at Argonne on May 11-13, 1981. In attendance were 96 scientists of whom 26 were from outside the United States. The present proceedings document the program and excitement of the field. Papers are arranged according to the original program. A few papers not presented at the meeting have been added to complete the information on the status of accelerator mass spectrometry. Individual papers were prepared separately for the data base.

None

1981-01-01T23:59:59.000Z

2

Early Days of Accelerator Mass Spectrometry  

DOE R&D Accomplishments (OSTI)

Alvarez reviews his role in the development of the tandem Van de Graaff accelerator and the technique of accelerator mass spectrometry as a technique for isotope dating. (GHT)

Alvarez, L. W.

1981-05-00T23:59:59.000Z

3

Toward laser ablation Accelerator Mass Spectrometry of actinides  

SciTech Connect

A project to measure neutron capture cross sections of a number of actinides in a reactor environment by Accelerator Mass Spectrometry (AMS) at the ATLAS facility of Argonne National Laboratory is underway. This project will require the precise and accurate measurement of produced actinide isotopes in many (>30) samples irradiated in the Advanced Test Reactor at Idaho National Laboratory with neutron fluxes having different energy distributions. The AMS technique at ATLAS is based on production of highlycharged positive ions in an electron cyclotron resonance (ECR) ion source followed by acceleration in the ATLAS linac and mass-to-charge (m/q) measurement at the focus of the Fragment Mass Analyzer. Laser ablation was selected as the method of feeding the actinide material into the ion source because we expect it will have higher efficiency and lower chamber contamination than either the oven or sputtering techniques, because of a much narrower angular distribution of emitted material. In addition, a new multi-sample holder/changer to allow quick change between samples and a computer-controlled routine allowing fast tuning of the accelerator for different beams, are being developed. An initial test run studying backgrounds, detector response, and accelerator scaling repeatability was conducted in December 2010. The project design, schedule, and results of the initial test run to study backgrounds are discussed.

R. C. Pardo; F. G. Kondev; S. Kondrashev; C. Nair; T. Palchan; R. Scott; D. Seweryniak; R. Vondrasek; M. Paul; P. Collon; C. Deibel; M. Salvatores; G. Palmiotti; J. Berg; J. Fonnesbeck; G. Imel

2013-01-01T23:59:59.000Z

4

Dating Studies of Elephant Tusks Using Accelerator Mass Spectrometry  

SciTech Connect

A new method for determining the year of birth, the year of death, and hence, the age at death, of post-bomb and recently deceased elephants has been developed. The technique is based on Accelerator Mass Spectrometry radiocarbon analyses of small-sized samples extracted from along the length of a ge-line of an elephant tusk. The measured radiocarbon concentrations in the samples from a tusk can be compared to the {sup 14}C atmospheric bomb-pulse curve to derive the growth years of the initial and final samples from the tusk. Initial data from the application of this method to two tusks will be presented. Potentially, the method may play a significant role in wildlife management practices of African national parks. Additionally, the method may contribute to the underpinnings of efforts to define new international trade regulations, which could, in effect, decrease poaching and the killing of very young animals.

Sideras-Haddad, E; Brown, T A

2002-10-03T23:59:59.000Z

5

Accelerator mass spectrometry in biomedical dosimetry: relationship between low-level exposure and covalent binding of heterocyclic amine carcinogens to DNA.  

Science Journals Connector (OSTI)

...Division, tCenter for Accelerator Mass Spectrometry, and Nuclear Chemistry Division...1990) ABSTRACT Accelerator mass spectrometry...Abbreviations: AMS, accelerator mass spectrometry...mixture was dried under vacuum in silica tubes and...

K W Turteltaub; J S Felton; B L Gledhill; J S Vogel; J R Southon; M W Caffee; R C Finkel; D E Nelson; I D Proctor; J C Davis

1990-01-01T23:59:59.000Z

6

Transition of Iodine Analysis to Accelerator Mass Spectrometry  

SciTech Connect

This NA 22 funded research project investigated the transition of iodine isotopic analyses from thermal ionization mass spectrometry (TIMS) to an accelerator mass spectrometry (AMS) system. Previous work (Fiscal Year 2010) had demonstrated comparable data from TIMS and AMS. With AMS providing comparable data with improved background levels and vastly superior sample throughput, improvement in the sample extraction from environmental sample matrices was needed to bring sample preparation throughput closer to the operation level of the instrument. Previous research used an extraction chemistry that was not optimized for yield or refined for reduced labor to prove the principle. This research was done to find an extraction with better yield using less labor per sample to produce a sample ready for the AMS instrument. An extraction method using tetramethyl ammonium hydroxide (TMAH) was developed for removal of iodine species from high volume air filters. The TMAH with gentle heating was superior to the following three extraction methods: ammonium hydroxide aided by sonication, acidic and basic extraction aided by microwave, and ethanol mixed with sodium hydroxide. Taking the iodine from the extraction solvent to being ready for AMS analysis was accomplished by a direct precipitation, as well as, using silver wool to harvest the iodine from the TMAH. Portions of the same filters processed in FY 2010 were processed again with the improved extraction scheme followed by successful analysis by AMS at the Swiss Federal Institute of Technology. The data favorably matched the data obtained in 2010. The time required for analysis has been reduced over the aqueous extraction/AMS approach developed in FY 2010. For a hypothetical batch of 30 samples, the AMS methodology is about 10 times faster than the traditional gas phase chemistry and TIMS analysis. As an additional benefit, background levels for the AMS method are about 1000 times lower than TIMS. This results from the fundamental mechanisms of ionization in the AMS system and which produces a beneficial cleanup of molecular interferences. Continued clean operation of the extraction process was demonstrated through blank analysis included with all sample sets analyzed. INL work showed improvement on the first year’s demonstration of AMS vs. TIMS. An improved extraction of high volume air filters followed by isotopic analysis by AMS, can be used successfully to make iodine measurements with results comparable to those obtained by filter combustion and TIMS analysis. More progress on the conversion from an extract solution to an AMS sample ready for analysis is still needed. Although the preparation scheme through AMS is already at a higher performing thoughput than TIMS, the chemical preparation cannot match the instrument capability for number of samples per day without further development.

M. L. Adamic; J. E. Olson; D. D. Jenson; J. G. Eisenmenger; M. G. Watrous

2012-09-01T23:59:59.000Z

7

Accelerator Mass Spectrometry | U.S. DOE Office of Science (SC)  

Office of Science (SC) Website

Accelerator Mass Spectrometry at ANL Accelerator Mass Spectrometry at ANL and ORNL Nuclear Physics (NP) NP Home About Research Facilities Science Highlights Benefits of NP Spinoff Applications Spinoff Archives SBIR/STTR Applications of Nuclear Science and Technology Funding Opportunities Nuclear Science Advisory Committee (NSAC) News & Resources Contact Information Nuclear Physics U.S. Department of Energy SC-26/Germantown Building 1000 Independence Ave., SW Washington, DC 20585 P: (301) 903-3613 F: (301) 903-3833 E: sc.np@science.doe.gov More Information » Spinoff Archives Accelerator Mass Spectrometry at ANL and ORNL Print Text Size: A A A RSS Feeds FeedbackShare Page Application/instrumentation: Accelerator Mass Spectrometry at ANL and ORNL Developed at: Argonne National Laboratory (ANL), Oak Ridge National Laboratory (ORNL)

8

E-Print Network 3.0 - accelerator mass spectrometry Sample Search...  

NLE Websites -- All DOE Office Websites (Extended Search)

accelerator mass... ATLAS Argonne Tandem Linear Accelerator System The prime national facility for nuclear structure... , accelerated in the world's first superconducting linear...

9

Accelerator Mass Spectrometry | U.S. DOE Office of Science (SC...  

Office of Science (SC) Website

Mass Spectrometry at ANL and ORNL Developed at: Argonne National Laboratory (ANL), Oak Ridge National Laboratory (ORNL) Developed in: Current Result of NP research: Basic NP...

10

Mass Spectrometry | EMSL  

NLE Websites -- All DOE Office Websites (Extended Search)

and Microfabrication Mass Spectrometry Microscopy Molecular Science Computing NMR and EPR Spectroscopy and Diffraction Subsurface Flow and Transport Mass Spectrometry Systems...

11

Interface for the rapid analysis of liquid samples by accelerator mass spectrometry  

DOE Patents (OSTI)

An interface for the analysis of liquid sample having carbon content by an accelerator mass spectrometer including a wire, defects on the wire, a system for moving the wire, a droplet maker for producing droplets of the liquid sample and placing the droplets of the liquid sample on the wire in the defects, a system that converts the carbon content of the droplets of the liquid sample to carbon dioxide gas in a helium stream, and a gas-accepting ion source connected to the accelerator mass spectrometer that receives the carbon dioxide gas of the sample in a helium stream and introduces the carbon dioxide gas of the sample into the accelerator mass spectrometer.

Turteltaub, Kenneth; Ognibene, Ted; Thomas, Avi; Daley, Paul F; Salazar Quintero, Gary A; Bench, Graham

2014-02-04T23:59:59.000Z

12

EMSL - Mass Spectrometry  

NLE Websites -- All DOE Office Websites (Extended Search)

mass-spectrometry Proteomics Capabilities High resolution and mass accuracy Fourier-transform ion cyclotron resonance (FT-ICR) spectrometers, from 6 Tesla (T) to 15T and 21T in...

13

Gas Chromatography -Mass Spectrometry  

E-Print Network (OSTI)

GCMS - 1 Gas Chromatography - Mass Spectrometry GC-MS ANALYSIS OF ETHANOL AND BENZENE IN GASOLINE Last updated: June 17, 2014 #12;GCMS - 2 Gas Chromatography - Mass Spectrometry GC-MS ANALYSIS). The goal of this experiment is to separate the components in a sample of gasoline using Gas Chromatography

Nizkorodov, Sergey

14

Analyzing Nuclear Fuel Cycles from Isotopic Ratios of Waste Products Applicable to Measurement by Accelerator Mass Spectrometry  

SciTech Connect

An extensive study was conducted to determine isotopic ratios of nuclides in spent fuel that may be utilized to reveal historical characteristics of a nuclear reactor cycle. This forensic information is important to determine the origin of unknown nuclear waste. The distribution of isotopes in waste products provides information about a nuclear fuel cycle, even when the isotopes of uranium and plutonium are removed through chemical processing. Several different reactor cycles of the PWR, BWR, CANDU, and LMFBR were simulated for this work with the ORIGEN-ARP and ORIGEN 2.2 codes. The spent fuel nuclide concentrations of these reactors were analyzed to find the most informative isotopic ratios indicative of irradiation cycle length and reactor design. Special focus was given to long-lived and stable fission products that would be present many years after their creation. For such nuclides, mass spectrometry analysis methods often have better detection limits than classic gamma-ray spectroscopy. The isotopic ratios {sup 151}Sm/{sup 146}Sm, {sup 149}Sm/{sup 146}Sm, and {sup 244}Cm/{sup 246}Cm were found to be good indicators of fuel cycle length and are well suited for analysis by accelerator mass spectroscopy.

Biegalski, S R; Whitney, S M; Buchholz, B

2005-08-24T23:59:59.000Z

15

EMSL: Capabilities: Mass Spectrometry: Next-Generation Mass Spectrometry  

NLE Websites -- All DOE Office Websites (Extended Search)

Next-Generation Mass Spectrometry Next-Generation Mass Spectrometry Additional Information Meet the Mass Spectrometry Experts Related EMSL User Projects Mass Spectrometry Tools are Applied to all Science Themes Next-Generation Mass Spectrometry Proteomics Research Resource for Integrative Biology Biological and Environmental Research - PNNL Proteomics PNNL's Biological MS Data and Software Distribution Center Mass Spectrometry brochure EMSL is committed to offering state-of-the-art instruments to its users. At a workshop in January of 2008, EMSL mass spectrometry experts joined experts from many universities, private companies, and government institutions and laboratories at a conference held at the National High Magnetic Field Laboratory in Tallahassee Florida. Workshop participants reviewed the state of the art of high-performance mass spectrometers,

16

MASS SPECTROMETRY WITH A VERY SMALL CYCLOTRON  

E-Print Network (OSTI)

OF CALIFORNIA mm Presented at the Argonne Symposium onHigh Energy Spectrometry, Argonne NationalLaboratory, Argonne, IL, May 11-13, 1981 MASS SPECTROMETRY

Muller, R.A.

2010-01-01T23:59:59.000Z

17

Electrospray Ionization Mass Spectrometry  

SciTech Connect

Electrospray Ionization (ESI) is a process whereby gas phase ions are created from molecules in solution. As a solution exits a narrow tube in the presence of a strong electric field, an aerosol of charged droplets are is formed that produces gas phase ions as they it desolvates. ESI-MS comprises the creation of ions by ESI and the determination of their mass to charge ratio (m/z) by MS.

Kelly, Ryan T.; Marginean, Ioan; Tang, Keqi

2014-06-13T23:59:59.000Z

18

Mass spectrometry: analytical capabilities and potentials  

Science Journals Connector (OSTI)

...INSULIN AND OTHER LARGE PEPTIDES, JOURNAL...MASS-SPECTROMETRY OF LARGE, FRAGILE, AND INVOLATILE...APPLICATIONS IN THE AREA OF MOLECULAR MODIFICATIONS...I-127-LABELED PLASMA DESORPTION MASS-SPECTROMETRY...PIONEER VENUS LARGE PROBE NEUTRAL MASS-SPECTROMETER...HORNING, E.C., ATMOSPHERIC-PRESSURE IONIZATION...

RG Cooks; KL Busch; GL Glish

1983-10-21T23:59:59.000Z

19

Absorption Mode FT-ICR Mass Spectrometry Imaging. | EMSL  

NLE Websites -- All DOE Office Websites (Extended Search)

Imaging. Absorption Mode FT-ICR Mass Spectrometry Imaging. Abstract: Fourier transform ion cyclotron resonance mass spectrometry offers the highest mass resolving power...

20

Ambient Ionization Mass Spectrometry Analysis Pertaining To Biofuel Process Development.  

E-Print Network (OSTI)

??Mass spectrometry (MS) has undergone a revolution with the introduction of a new group of desorption/ionization (DI) techniques known collectively as Ambient Ionization mass spectrometry.… (more)

Dendukuri, Sushma

2012-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "accelerator mass spectrometry" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

High-Performance Mass Spectrometry Facility  

NLE Websites -- All DOE Office Websites (Extended Search)

HPMSF Overview HPMSF Overview Section 2-4-1 High-Performance Mass Spectrometry Facility The High-Performance Mass Spectrometry Facility (HPMSF) provides state-of-the-art mass spectrometry (MS) and separations instrumentation that has been refined for leading-edge analysis of biological problems with a primary emphasis on proteomics. Challenging research in proteomics, cell signaling, cellular molecular machines, and high-molecular weight systems receive the highest priority for access to the facility. Current research activities in the HPMSF include proteomic analyses of whole cell lysates, analyses of organic macro-molecules and protein complexes, quantification using isotopically labeled growth media, targeted proteomics analyses of subcellular fractions, and nucleic acid analysis of

22

High performance ²?²Cf plasma desorption mass spectrometry  

E-Print Network (OSTI)

ABSTRACT . ACKNOWLEDGEMENT TABLE OF CONTENTS . tv LIST OF TABLES LIST OF FIGURES C~R I. INTRODUCTION tx xt A. A General Overview . 1. Particle-Induced Desorption 2. The Application of Cf PDMS in Analytical Chemistry 3. Time-of-Flight Mass... INTRODUCTION The method of 'Cf plasma desorption mass spectrometry (PDMS) is a mass spectrometric method pioneered in 1974 by Macfarlane and co-workers (1) at Texas A&M University. This method uses fission fragments (highly energetic atomic ions...

McIntire, Thomas Shane

1991-01-01T23:59:59.000Z

23

A Brief History of Mass Spectrometry  

Science Journals Connector (OSTI)

A Brief History of Mass Spectrometry ... More complete histories of MS are available both in print (e.g., Ref. 1) and on the web. ... He began his academic career as an electrical engineer but, because of the paucity of engineering courses available at the time, eventually turned to physics for his graduate work at the Minnesota. ...

Jennifer Griffiths

2008-07-31T23:59:59.000Z

24

Instrument Series: Mass Spectrometry SPLAT II  

NLE Websites -- All DOE Office Websites (Extended Search)

Mass Spectrometry Mass Spectrometry SPLAT II SPLAT II is a one-of-a-kind single particle mass spectrometer that was designed, constructed, and deployed at EMSL to allow users to precisely characterize the physical and chemical properties of nanoparticles. SPLAT II yields quantitative information on particle physical and chemical properties in the laboratory or in the field-even aboard an aircraft. In the context of EMSL's integrated problem-solving environment, the unique capabilities of SPLAT II enable vital research across a range of scientific fields. Research Applications Fundamental science - characterizing the properties and behavior of matter on the nanoscale Atmospheric chemistry - understanding the processes that control atmospheric aerosol life cycle Climate change - uncovering and helping

25

Monolithic multinozzle emitters for nanoelectrospray mass spectrometry  

DOE Patents (OSTI)

Novel and significantly simplified procedures for fabrication of fully integrated nanoelectrospray emitters have been described. For nanofabricated monolithic multinozzle emitters (NM.sup.2 emitters), a bottom up approach using silicon nanowires on a silicon sliver is used. For microfabricated monolithic multinozzle emitters (M.sup.3 emitters), a top down approach using MEMS techniques on silicon wafers is used. The emitters have performance comparable to that of commercially-available silica capillary emitters for nanoelectrospray mass spectrometry.

Wang, Daojing (Daly City, CA); Yang, Peidong (Kensington, CA); Kim, Woong (Seoul, KR); Fan, Rong (Pasadena, CA)

2011-09-20T23:59:59.000Z

26

High-Resolution Electrospray Ionization Mass Spectrometry Analysis...  

NLE Websites -- All DOE Office Websites (Extended Search)

Mass Spectrometry Analysis of Water- Soluble Organic Aerosols Collected with a Particle Abstract: This work demonstrates the utility of a particle-into-liquid sampler (PILS) a...

27

In situ secondary ion mass spectrometry analysis  

SciTech Connect

The direct detection of tributyl phosphate (TBP) on rocks using molecular beam surface analysis [MBSA or in situ secondary ion mass spectrometry (SIMS)] is demonstrated. Quantities as low as 250 ng were detected on basalt and sandstone with little or no sample preparation. Detection of TBP on soil has proven to be more problematic and requires further study. Ethylenediaminetetraacetic acid (EDTA) is more difficult to detect because it is very reactive with surfaces of interest. Nevertheless, it is possible to detect EDTA if the acidity of the surface is controlled. The detection of EDTA-metal complexes is currently an open question, but evidence is presented for the detection of ions arising from a EDTA-lead complex. Carboxylic acids (i.e., citric, ascorbic, malic, succinic, malonic, and oxalic) give characteristic SIM spectra, but their detection on sample surfaces awaits evaluation.

Groenewold, G.S.; Applehans, A.D.; Ingram, J.C.; Delmore, J.E.; Dahl, D.A.

1993-01-01T23:59:59.000Z

28

Single Cell Analysis Using Microfluidics Coupled to Ultrasensitive Mass Spectrometry  

E-Print Network (OSTI)

Single Cell Analysis Using Microfluidics Coupled to Ultrasensitive Mass Spectrometry PI Ryan Kelly is to combine microfluidic sample preparation and separations with the ultrasensitive mass spectrometry (MS without the need for chemical labeling. We will combine our expertise in the fields of microfluidics

29

Evaluation of histone sequence and modifications by electrospray ionization mass spectrometry and tandem mass spectrometry  

SciTech Connect

The histones, together with other specialized proteins and DNA, form the extraordinarily complex structure of chromatin. Electrospray ionization (ESI) permits the promotion of such protein species into the gas phase as intact, multiply charged molecular species. Mass spectrometry (MS), using a linear quadrupole mass filter, permits measurement of the relative molecular mass of these intact species with precision and accuracy. The latter are sufficient to evaluate variations in the primary structure of the histones and the type and extent of the natural and induced multiple covalent modifications. The locations of modifications are revealed by tandem mass spectrometry using tandem linear quadrupole or ion trap instruments on the intact species or the modified peptides derived by selective proteolysis. Experiments in applying this technique to histones from K562, a human-derived cell line, have demonstrated variations in the profile of modification through the normal cell cycle and in the presence of agents that inhibit enzymes responsible for reversal of the modification. The authors are currently testing the hypothesis that ESI-MS will permit the sensitive and selective identification of insult-induced modifications, distinguishing them from natural cell-cycle changes. This will be possible because ESI-MS reveals the full details of the profile of multiple posttranslational modifications of histones.

Edmonds, C.G.; Loo, J.A.; Smith, R.D.; Fuciarelli, A.F.; Thrall, B.D.; Morris, J.E.; Springer, D.L. (Pacific Northwest Lab., Richland, WA (United States))

1993-01-01T23:59:59.000Z

30

Mass determination of megadalton-DNA Electrospray Ions usingCharge Detection Mass Spectrometry  

SciTech Connect

Charge detection mass spectrometry (CD-MS) has been used to determine the mass of double-stranded, circular DNA and single-stranded, circular DNA in the range of 2500 to 8000 base pairs (1.5-5.0 MDa). Simultaneous measurement of the charge and velocity of an electrostatically accelerated ion allows a mass determination of the ion, with instrument calibration determined independently of samples. Positive ion mass spectra of electrosprayed commercial DNA samples supplied in tris(hydroxymethyl)ethylenediamine tetraacetic acid buffer, diluted in 50 vol. percent acetonitrile, were obtained without cleanup of the sample. ACD mass spectrum constructed from 3000 ion measurements takes 10 min to acquire and yields the DNA molecular mass directly (mass resolution = 6). The data collected represent progress toward a more automatable alternative to sizing of DNA by gel electrophoresis. In addition to the mass spectra, CD-MS generates charge versus mass plots, which provide another means to investigate the creation and fate of large electrospray ions.

Schultz, Jocelyn C.; Hack, Christopher; Benner, Henry W.

1997-10-01T23:59:59.000Z

31

E-Print Network 3.0 - aerosol mass spectrometry Sample Search...  

NLE Websites -- All DOE Office Websites (Extended Search)

used in health effects studies by aerosol mass spectrometry Wingen, L... and heats of sublimation using atmospheric solids analysis probe mass spectrometry (ASAP-MS) Bruns E......

32

Analysis of perchlorate in groundwater by electrospray ionization mass spectrometry/mass spectrometry  

SciTech Connect

An electrospray ionization mass spectrometry/mass spectrometry (ESI/MS/MS) method was developed to measure part-per-billion ({micro}g/L) concentrations of perchlorate in groundwater. Selective and sensitive perchlorate detection was achieved by operating the mass spectrometer in the negative ionization mode and by using MS/MS to monitor the CIO{sub 4}{sup {minus}} to ClO{sub 3}{sup {minus}} transition. The method of standard additions was used to address the considerable signal suppression caused by anions that are typically present in groundwater, such as bicarbonate and sulfate. ESI-MS/MS analysis was rapid, accurate, reproducible, and provided a detection limit of 0.5 {micro}g/L perchlorate in groundwater. Accuracy and precision of the ESI/MS/MS method were assessed by analyzing performance evaluation samples in a groundwater matrix and by comparing ion chromatography (IC) and ESI/MS/MS results for local groundwater samples. Results for the performance evaluation samples differed from the certified values by 4--13%, and precision ranged from 3 to 10% (relative standard deviation). The IC and ESI/MS/MS results were statistically indistinguishable for perchlorate concentrations above the detection limits of both methods.

Koester, C.J.; Beller, H.R.; Halden, R.U.

2000-05-01T23:59:59.000Z

33

Laser mass spectrometry for DNA sequencing, disease diagnosis, and fingerprinting  

SciTech Connect

Since laser mass spectrometry has the potential for achieving very fast DNA analysis, the authors recently applied it to DNA sequencing, DNA typing for fingerprinting, and DNA screening for disease diagnosis. Two different approaches for sequencing DNA have been successfully demonstrated. One is to sequence DNA with DNA ladders produced from Snager`s enzymatic method. The other is to do direct sequencing without DNA ladders. The need for quick DNA typing for identification purposes is critical for forensic application. The preliminary results indicate laser mass spectrometry can possibly be used for rapid DNA fingerprinting applications at a much lower cost than gel electrophoresis. Population screening for certain genetic disease can be a very efficient step to reducing medical costs through prevention. Since laser mass spectrometry can provide very fast DNA analysis, the authors applied laser mass spectrometry to disease diagnosis. Clinical samples with both base deletion and point mutation have been tested with complete success.

Winston Chen, C.H.; Taranenko, N.I.; Zhu, Y.F.; Chung, C.N.; Allman, S.L.

1997-03-01T23:59:59.000Z

34

Applications of Secondary Ion Mass Spectrometry (SIMS) in Materials Science  

Science Journals Connector (OSTI)

Secondary Ion Mass Spectrometry (SIMS) is a mature surface analysis technique with ... Materials Science. In this review article the SIMS process is described, the fundamental SIMS equations are derived and the m...

D. S. McPhail

2006-02-01T23:59:59.000Z

35

Oil-Spill Identification by Gas Chromatography-Mass Spectrometry  

Science Journals Connector (OSTI)

...May-June research-article Articles Oil-Spill Identification by Gas Chromatography-Mass Spectrometry...the identification of a contaminant caused by the spilling of oil or oil products in water. A capillary gas chromatography (CGC......

A. Pavlova; D. Papazova

36

Subcellular analysis by laser ablation electrospray ionization mass spectrometry  

DOE Patents (OSTI)

In various embodiments, a method of laser ablation electrospray ionization mass spectrometry (LAESI-MS) may generally comprise micro-dissecting a cell comprising at least one of a cell wall and a cell membrane to expose at least one subcellular component therein, ablating the at least one subcellular component by an infrared laser pulse to form an ablation plume, intercepting the ablation plume by an electrospray plume to form ions, and detecting the ions by mass spectrometry.

Vertes, Akos; Stolee, Jessica A; Shrestha, Bindesh

2014-12-02T23:59:59.000Z

37

Secondary Ion Mass Spectrometry Imaging of Dictyostelium discoideum Aggregation Streams  

SciTech Connect

High resolution imaging mass spectrometry could become a valuable tool for cell and developmental biology, but both, high spatial and mass spectral resolution are needed to enable this. In this report, we employed Bi3 bombardment time-of-flight (Bi3 ToF-SIMS) and C60 bombardment Fourier transform ion cyclotron resonance secondary ion mass spectrometry (C60 FTICR-SIMS) to image Dictyostelium discoideum aggregation streams. Nearly 300 lipid species were identified from the aggregation streams. High resolution mass spectrometry imaging (FTICR-SIMS) enabled the generation of multiple molecular ion maps at the nominal mass level and provided good coverage for fatty acyls, prenol lipids, and sterol lipids. The comparison of Bi3 ToF-SIMS and C60 FTICR-SIMS suggested that while the first provides fast, high spatial resolution molecular ion images, the chemical complexity of biological samples warrants the use of high resolution analyzers for accurate ion identification.

Debord, J. Daniel; Smith, Donald F.; Anderton, Christopher R.; Heeren, Ronald M.; Pasa-Tolic, Ljiljana; Gomer, Richard H.; Fernandez-Lima, Francisco A.

2014-06-09T23:59:59.000Z

38

Direct analysis of samples by mass spectrometry: From elements to bio-molecules using laser ablation inductively couple plasma mass spectrometry and laser desorption/ionization mass spectrometry  

SciTech Connect

Mass spectrometric methods that are able to analyze solid samples or biological materials with little or no sample preparation are invaluable to science as well as society. Fundamental research that has discovered experimental and instrumental parameters that inhibit fractionation effects that occur during the quantification of elemental species in solid samples by laser ablation inductively coupled plasma mass spectrometry is described. Research that determines the effectiveness of novel laser desorption/ionization mass spectrometric methods for the molecular analysis of biological tissues at atmospheric pressure and at high spatial resolution is also described. A spatial resolution is achieved that is able to analyze samples at the single cell level.

Perdian, David C.

2009-08-19T23:59:59.000Z

39

Coming to a hospital near you: mass spectrometry imaging  

SciTech Connect

Berkeley Lab's Ben Bowen discusses "Coming to a hospital near you: mass spectrometry imaging" in this Oct. 28, 2013 talk, which is part of a Science at the Theater event entitled Eight Big Ideas. Go here to watch the entire event with all 8 speakers.

Bowen, Ben

2013-10-31T23:59:59.000Z

40

Coming to a hospital near you: mass spectrometry imaging  

ScienceCinema (OSTI)

Berkeley Lab's Ben Bowen discusses "Coming to a hospital near you: mass spectrometry imaging" in this Oct. 28, 2013 talk, which is part of a Science at the Theater event entitled Eight Big Ideas. Go here to watch the entire event with all 8 speakers.

Bowen, Ben

2014-06-24T23:59:59.000Z

Note: This page contains sample records for the topic "accelerator mass spectrometry" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Mass spectrometry: analytical capabilities and potentials  

Science Journals Connector (OSTI)

...inductively ~hlorodibencoupled plasma (ICP) mass spectrome-a coal...design have long been used for atmospheric and plan-etary exploration...digitization rates of 30 to 100 kHz for GC-IR and 100 kHz to 5 MHz for GC-MS) and the equally...

RG Cooks; KL Busch; GL Glish

1983-10-21T23:59:59.000Z

42

Aerosol mass spectrometry systems and methods  

DOE Patents (OSTI)

A system according to one embodiment includes a particle accelerator that directs a succession of polydisperse aerosol particles along a predetermined particle path; multiple tracking lasers for generating beams of light across the particle path; an optical detector positioned adjacent the particle path for detecting impingement of the beams of light on individual particles; a desorption laser for generating a beam of desorbing light across the particle path about coaxial with a beam of light produced by one of the tracking lasers; and a controller, responsive to detection of a signal produced by the optical detector, that controls the desorption laser to generate the beam of desorbing light. Additional systems and methods are also disclosed.

Fergenson, David P.; Gard, Eric E.

2013-08-20T23:59:59.000Z

43

Mass spectrometry of proteins of known mass Andrew D. Miranker*  

E-Print Network (OSTI)

deter- mination has two significant advantages. First, the mass accuracy under these conditions to the orifice of the mass analyzer. As a result, there is a local separation of charges at the tip

Miranker, Andrew

44

Determination of boron isotope ratios in geological materials by inductively coupled plasma mass spectrometry  

Science Journals Connector (OSTI)

Determination of boron isotope ratios in geological materials by inductively coupled plasma mass spectrometry ... Isotope dilution analysis using flow injection inductively coupled plasma mass spectrometry was applied to determine low boron contents in iron and steel samples. ...

D. Conrad Gregoire

1987-10-01T23:59:59.000Z

45

Tandem Mass Spectrometry identifies many mouse brain O-GlcNAcylated...  

NLE Websites -- All DOE Office Websites (Extended Search)

Tandem Mass Spectrometry identifies many mouse brain O-GlcNAcylated proteins including EGF domain-specific O-GlcNAc transferase Tandem Mass Spectrometry identifies many mouse brain...

46

Observing the invisible through imaging mass spectrometry, a window into the metabolic exchange patterns of microbes  

E-Print Network (OSTI)

Observing the invisible through imaging mass spectrometry, a window into the metabolic exchange this article as: Gonzalez DJ., et al, Observing the invisible through imaging mass spectrometry, a window

Nizet, Victor

47

Single Cell Analysis Using Microfluidics Coupled to Ultrasensitive Mass Spectrometry  

NLE Websites -- All DOE Office Websites (Extended Search)

Cell Analysis Using Microfluidics Coupled to Ultrasensitive Mass Cell Analysis Using Microfluidics Coupled to Ultrasensitive Mass Spectrometry PI Ryan Kelly, EMSL Co-investigators Xuefei Sun, FCSD, Bryan Linggi, EMSL, Keqi Tang, FCSD Proteomics and metabolomics measurements in their present form require large populations of cells and thus average over and obscure important heterogeneity that is present even in clonal populations cultivated under highly controlled conditions. For "real world" samples, this means that important but rare events go undetected, and the effects of stochastic expression and the microenvironment are blurred. The objective of this proposal is to combine microfluidic sample preparation and separations with the ultrasensitive mass spectrometry (MS) capability located in the EMSL to extend proteomic and

48

Electrospray Ionization Mass Spectrometry of hexanitrohexaazaisowurtzitane (CL-20)  

SciTech Connect

Hexanitrohexaazaisowurtzitane, (C6H6N12O12, MW 438) {CL-20}, is a high-energy propellent that has been recently developed and successfully tested (Nielsen et al. 1998). CL-20 releases more energy on ignition and is more stable to accidental detonation than currently used energetic materials. It is expected to replace many of the energetic materials currently being used by the Department of Defense (DoD). The EPA method 8330 (EPA 1997) for the analysis of explosives and metabolites in soils calls for the use of UV/Vis detection. High performance liquid chromatography has been used to quantify CL-20 and precursor concentration (Bazaki et al. 1998`) at relatively high concentrations. Fourier transform infrared (FTIR) spectroscopy has been used to identify different crystal forms of CL-20 (4 isomers; Kim et al. 1998). Campbell et al. (1997) utilized particle beam mass spectrometry for the analysis of enzymatic degradation of explosives. Introduction and recent improvements of ionization techniques such as electrospray (ES) have allowed the mass spectrometer to become more widely used in liquid chromatography. Schilling(1996) also examined explosive components and metabolites using electrospray (ES) and atmospheric pressure chemical ionization (APCI) liquid chromatography/mass spectrometry (LC/MS). Schilling’s results showed that compared to thermospray LC/MS, APCI and ES were more sensitive than thermospray by at least an order of magnitude. 1,3,5-trinitro-1,3,5-triazacyclohexane (RDX), 10 nitroso-RDX metabolites, and other munitions in ground water have been analyzed using solid phase extraction and isotope dilution liquid chromatography-APCI mass spectrometry (Cassada et al. 1999). The method detection limits indicate that nitramine and nitroaromatic compounds can be routinely determined in ground water samples using electrospray LC/MS with concentration techniques utilizing solid-phase extraction. Miller et al. (1996) studied nitrated explosives with mobile phase additives to enhance the ESI intensities and spectral consistencies. Several of the explosives gave nitrate adduct ions in the negative mode with ammonium nitrate as the mobile phase. The nitramines RDX and 1,3,5,7-tetranitro-1,3,5,7 tetraazacyclooctane (HMX) showed the greatest enhancement in response of the explosives. Ammonium nitrate was used as the mobile phase and made it possible to obtain consistent and interpretable LC/MS spectra at the nanogram level. Campbell et al. (1999), Shi et al. (2000), and Goheen et al. (1999) utilized electrospray ionization mass spectrometry for the identification of degradation products of explosives. Yinon et al. (1997) used ESI and tandem mass spectrometry collision-induced dissociation to examine several nitramine compounds including trinitrotolutene (TNT), RDX, and pentaerythritol tetranitrate (PETN). The results indicate that explosives can be detected in the negative ion mode and characterized by various adduct ions. As an example, for nitroglycerin, the major adduct ion observed was (M+ONO2)-. In addition, Harvey et al. (1992) have used direct probe mass spectrometry for the analysis of degradation products of tetryl and its transformation products in soil. The negative ion electrospray mass spectrum of CL-20 is reported here. The major adduct ions observed under negative ion conditions were (M+Cl)- at m/z 473 and (M+ONO2) – at m/z 500. In addition, the results of mass spectrometry/mass spectrometry studies are also discussed.

Campbell, James A.; Szecsody, Jim E.; Devary, Brooks J.; Valenzuela, Blandina R.

2007-09-03T23:59:59.000Z

49

SIMS—A precursor and partner to contemporary mass spectrometry  

Science Journals Connector (OSTI)

Abstract Significant events driving the development of SIMS over the last 50 years are reviewed. The discussion includes recollections of dynamic and static SIMS from the 1970s, of the emergence of TOF–SIMS during the 1980s and of the incorporation of cluster ion bombardment during most recent times. Advances in theoretical understanding of the sputtering phenomenon and of the ionization process that accompanied these advances are also included. Many early discoveries were focused upon the stimulated desorption of organic and bioorganic molecules, first via static SIMS and next via fast atom bombardment, that were important precursor experiments to modern day mass spectrometry. Today, submicron molecule-specific imaging and molecular depth profiling represent unique aspects of SIMS experiments. Developments that led to the optimization of these modalities are also emphasized in the review. In general, the characteristics of SIMS that make it a contemporary partner to modern day mass spectrometry are highlighted.

John C. Vickerman; Nicholas Winograd

2014-01-01T23:59:59.000Z

50

Chip-Scale Quadrupole Mass Filters for Portable Mass Spectrometry  

E-Print Network (OSTI)

We report the design, fabrication, and characterization of a new class of chip-scale quadrupole mass filter (QMF). The devices are completely batch fabricated using a wafer-scale process that integrates the quadrupole ...

Cheung, Kerry

51

Isoelectric Trapping and Mass Spectrometry: Tools for Proteomics  

E-Print Network (OSTI)

ISOELECTRIC TRAPPING AND MASS SPECTROMETRY: TOOLS FOR PROTEOMICS A Dissertation by STEPHANIE MARIE COLOGNA Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements... of Texas A&M University in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY Approved by: Chair of Committee, David H. Russell Committee Members, Paul S. Cremer Arul Jayaraman Gyula Vigh Head of Department, David H...

Cologna, Stephanie Marie

2012-02-14T23:59:59.000Z

52

JOURNAL OF MASS SPECTROMETRY J. Mass Spectrom. 2003; 38: 277282  

E-Print Network (OSTI)

tandem mass spectrom- etry even isomerizations such as isoaspartate formation are detectable.3 Low-energy, nuclear and endosomal morphology, a defect in fluid-phase uptake and an impairment in normal cytokinesis.1.02 derived from acrylamide-modified peptides.8 These fragmentation reactions can be utilized for the spe-

Manstein, Dietmar J.

53

Fourier transform mass spectrometry of high-mass biomolecules  

SciTech Connect

In this report the authors present an overview of the use of FTMS for the analysis of large biomolecules, with emphasis on recent developments in coupling ESI and MALDI with FTMS. A simple description of the principles of FTMS operation and experimental factors that are relevant to the examination of large molecules are also presented. The examples represent state-of-the-art capabilities of FTMS. On the basis of early reports, it is apparent that the applications of FTMS for the analysis of biopolymers will expand rapidly in the near future. Although many different types of mass analyzers are compatible with FAB, ESI, and MALDI, FTMS has exhibited particular potential for high sensitivity, accurate mass measurement, high-mass resolution, and structural characterization of large biopolymers. The recent results obtained with both ESI-FTMS and MALDI-FTMS are very exciting with respect to both fundamental advances in the capabilities of FTMS and potential applications in the biochemical laboratory. 63 refs., 6 figs., 1 tab.

Buchanan, M.V.; Hettich, R.L. (Oak Ridge National Lab., TN (United States))

1993-03-01T23:59:59.000Z

54

Quantitative Mapping of 4?-Iododeoxyrubicin in Metastatic Squamous Cell Carcinoma by Secondary Ion Mass Spectrometry (SIMS) Microscopy  

Science Journals Connector (OSTI)

...Carcinoma by Secondary Ion Mass Spectrometry (SIMS) Microscopy 1 1 This work was supported...cellcarcinoma by secondary ion mass spectrometry (SIMS) microscopy. | Secondary ion mass spectrometry...Carcinoma by Secondary Ion Mass Spectrometry (SIMS) Microscopy1 Philippe Fragu,2 Jerzy...

Philippe Fragu; Jerzy Klijanienko; Daniel Gandia; Sylvain Halpern; Jean-Pierre Armand

1992-02-15T23:59:59.000Z

55

Future Directions of Structural Mass Spectrometry using Hydroxyl Radical Footprinting  

SciTech Connect

Hydroxyl radical protein footprinting coupled to mass spectrometry has been developed over the last decade and has matured to a powerful method for analyzing protein structure and dynamics. It has been successfully applied in the analysis of protein structure, protein folding, protein dynamics, and protein-protein and protein-DNA interactions. Using synchrotron radiolysis, exposure of proteins to a 'white' X-ray beam for milliseconds provides sufficient oxidative modification to surface amino acid side chains, which can be easily detected and quantified by mass spectrometry. Thus, conformational changes in proteins or protein complexes can be examined using a time-resolved approach, which would be a valuable method for the study of macromolecular dynamics. In this review, we describe a new application of hydroxyl radical protein footprinting to probe the time evolution of the calcium-dependent conformational changes of gelsolin on the millisecond timescale. The data suggest a cooperative transition as multiple sites in different molecular subdomains have similar rates of conformational change. These findings demonstrate that time-resolved protein footprinting is suitable for studies of protein dynamics that occur over periods ranging from milliseconds to seconds. In this review, we also show how the structural resolution and sensitivity of the technology can be improved as well. The hydroxyl radical varies in its reactivity to different side chains by over two orders of magnitude, thus oxidation of amino acid side chains of lower reactivity are more rarely observed in such experiments. Here we demonstrate that the selected reaction monitoring (SRM)-based method can be utilized for quantification of oxidized species, improving the signal-to-noise ratio. This expansion of the set of oxidized residues of lower reactivity will improve the overall structural resolution of the technique. This approach is also suggested as a basis for developing hypothesis-driven structural mass spectrometry experiments.

J Kiselar; M Chance

2011-12-31T23:59:59.000Z

56

New developments in biochemical mass spectrometry: Electrospray ionization  

SciTech Connect

The principles, development, and recent application of electrospray ionization-mass spectrometry (ESI-MS) to biological compounds are reviewed. ESI-MS methods now allow determination of accurate molecular weights for proteins extending to over 50,000, and in some cases well over 100,000. Similar capabilities are being developed for oligonucleotides. The instrumentation used for ESI-MS is briefly described and it is shown that, although ionization efficiency appears to be uniformly high, detector sensitivity may be directly correlated with molecular weight. The use of tandem mass spectrometry (e.g., MS/MS) for extending collision-induced dissociation (CID) methods to the structural studies of large molecules is described. For example, effective CID of various albumin species (molecular weight {approximately}66,000) can be obtained, far larger than obtainable for singly charged molecular ions. The combination of capillary electrophoresis, in both free solution zone electrophoresis and isotachophoresis formats, as well as microcolumn liquid chromatography with ESI-MS, provides the capability for on-line separation and analysis of subpicomole quantities of proteins. These and other new developments related to ESI-MS are illustrated by a range of examples. Fundamental considerations suggest even more impressive developments may be anticipated related to detection sensitivity and methods for obtaining structural information.

Smith, R.D.; Loo, J.A.; Edmonds, C.G.; Barinaga, C.J.; Udseth, H.R. (Pacific Northwest Laboratory, Richland, WA (USA))

1990-05-01T23:59:59.000Z

57

Analysis of hazardous biological material by MALDI mass spectrometry  

SciTech Connect

Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-MS) has become a valuable tool for analyzing microorganisms. The speed with which data can be obtained from MALDI-MS makes this a potentially important tool for biological health hazard monitoring and forensic applications. The excitement in the mass spectrometry community in this potential field of application is evident by the expanding list of research laboratories pursuing development of MALDI-MS for bacterial identification. Numerous research groups have demonstrated the ability to obtain unique MALDI-MS spectra from intact bacterial cells and bacterial cell extracts. The ability to differentiate strains of the same species has been investigated. Reproducibility of MALDI-MS spectra from bacterial species under carefully controlled experimental conditions has also been demonstrated. Wang et al. have reported on interlaboratory reproducibility of the MALDI-MS analysis of several bacterial species. However, there are still issues that need to be addressed, including the careful control of experimental parameters for reproducible spectra and selection of optimal experimental parameters such as solvent and matrix.

KL Wahl; KH Jarman; NB Valentine; MT Kingsley; CE Petersen; ST Cebula; AJ Saenz

2000-03-21T23:59:59.000Z

58

Laser ablation electrospray ionization (LAESI) for atmospheric pressure, In vivo, and imaging mass spectrometry  

DOE Patents (OSTI)

The field of the invention is atmospheric pressure mass spectrometry (MS), and more specifically a process and apparatus which combine infrared laser ablation (LA) with electrospray ionization (ESI).

Vertes, Akos (Reston, VA); Nemes, Peter (Silver Spring, MD)

2011-11-29T23:59:59.000Z

59

Laser ablation electrospray ionization (LAESI) for atmospheric pressure, in vivo, and imaging mass spectrometry  

DOE Patents (OSTI)

The field of the invention is atmospheric pressure mass spectrometry (MS), and more specifically a process and apparatus which combine infrared laser ablation with electrospray ionization (ESI).

Vertes, Akos; Nemes, Peter

2014-08-19T23:59:59.000Z

60

Laser ablation electrospray ionization (LAESI) for atmospheric pressure, in vivo, and imaging mass spectrometry  

DOE Patents (OSTI)

The field of the invention is atmospheric pressure mass spectrometry (MS), and more specifically a process and apparatus which combine infrared laser ablation with electrospray ionization (ESI).

Vertes, Akos; Nemes, Peter

2013-07-16T23:59:59.000Z

Note: This page contains sample records for the topic "accelerator mass spectrometry" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Three-dimensional molecular imaging by infrared laser ablation electrospray ionization mass spectrometry  

DOE Patents (OSTI)

The field of the invention is atmospheric pressure mass spectrometry (MS), and more specifically a process and apparatus which combine infrared laser ablation with electrospray ionization (ESI).

Vertes, Akos; Nemes, Peter

2013-07-16T23:59:59.000Z

62

Three-dimensional molecular imaging by infrared laser ablation electrospray ionization mass spectrometry  

DOE Patents (OSTI)

The field of the invention is atmospheric pressure mass spectrometry (MS), and more specifically a process and apparatus which combine infrared laser ablation with electrospray ionization (ESI).

Vertes, Akos; Nemes, Peter

2012-10-30T23:59:59.000Z

63

Atmospheric-Pressure Helium Inductively Coupled Plasmas for Elemental Mass Spectrometry  

Science Journals Connector (OSTI)

Analytical and fundamental characteristics of helium inductively coupled plasma mass spectrometry (He ICPMS) were explored for atmospheric-pressure plasmas generated in a 13-mm He...

Zhang, Hao; Nam, Sang-Ho; Cai, Mingxiang; Montaser, Akbar

1996-01-01T23:59:59.000Z

64

Detection of methoxylated anions of fullerenes by electrospray ionization mass spectrometry  

SciTech Connect

Electrospray ionization mass spectrometry (ESI-MS) has been applied to the study of the reactions of fullerenes in solution. The C[sub 60][sup [minus

Wilson, S.R.; Wu, Y. (New York Univ., NY (United States))

1993-11-03T23:59:59.000Z

65

E-Print Network 3.0 - analytical mass spectrometry Sample Search...  

NLE Websites -- All DOE Office Websites (Extended Search)

of cluster primary ion beams for applications in secondary ion mass spectrometry (SIMS), motivated... surface analysis, microscopy, ion solid interactions, biological and...

66

E-Print Network 3.0 - atomic mass spectrometry Sample Search...  

NLE Websites -- All DOE Office Websites (Extended Search)

of cluster primary ion beams for applications in secondary ion mass spectrometry (SIMS), motivated... surface analysis, microscopy, ion solid interactions, biological and...

67

Correction of accurate mass measurement for target compound verification by quadrupole time-of-flight mass spectrometry  

Science Journals Connector (OSTI)

The aim of this work is to evaluate quadrupole/time-of-flight (QTOF) mass spectrometry for simultaneous measurement of accurate mass and quantification of a target by using a stable isotopically labeled intern...

Harald C. Köfeler…

2005-03-01T23:59:59.000Z

68

Ion Mobility SpectrometryMass Spectrometry Performance Using Electrodynamic Ion Funnels and Elevated Drift Gas Pressures  

SciTech Connect

The ability of ion mobility spectrometry coupled with mass spectrometry (IMS-MS) to characterize biological mixtures has been illustrated over the past eight years. However, the challenges posed by the extreme complexity of many biological samples have demonstrated the need for higher resolution IMS-MS measurements. We have developed a higher resolution ESI-IMS-TOF MS by utilizing high pressure electrodynamic ion funnels at both ends of the IMS drift cell and operating the drift cell at an elevated pressure compared to a previous design. The ESI-IMS-TOF MS instrument consists of an ESI source, an hourglass ion funnel used for ion accumulation/injection into an 88 cm drift cell followed by a 10 cm ion funnel and a commercial orthogonal time-of-flight mass spectrometer providing high mass measurement accuracy. It was found that the rear (exit) ion funnel could be effectively operated as an extension of the drift cell when the DC fields were matched, allowing the instrument to have an effective drift region of 98 cm. Two differentially pumped quadrupole regions were used to couple the IMS and TOF MS to focus and minimize the ion transient time between the stages. The resolution of the instrument was evaluated at pressures ranging from 4 to12 Torr and ion mobility drift voltages of 16 V/cm (4 Torr) to 43 V/cm (12 Torr). An increase in resolution from 55 to 80 was observed from 4 to 12 Torr nitrogen drift gas with no loss in sensitivity. Given the increased usage of ion funnels prior to ion mobility separations, additional attention was directed towards the influence of drift gas on the observed ion populations trapped and transmitted using an electrodynamic ion funnel. The choice of drift gas was shown to influence the degree of ion heating and relative trapping efficiency within the ion funnel.

Baker, Erin Shammel; Clowers, Brian H.; Li, Fumin; Tang, Keqi; Tolmachev, Aleksey V.; Prior, David C.; Belov, Mikhail E.; Smith, Richard D.

2007-06-28T23:59:59.000Z

69

In situ secondary ion mass spectrometry analysis. 1992 Summary report  

SciTech Connect

The direct detection of tributyl phosphate (TBP) on rocks using molecular beam surface analysis [MBSA or in situ secondary ion mass spectrometry (SIMS)] is demonstrated. Quantities as low as 250 ng were detected on basalt and sandstone with little or no sample preparation. Detection of TBP on soil has proven to be more problematic and requires further study. Ethylenediaminetetraacetic acid (EDTA) is more difficult to detect because it is very reactive with surfaces of interest. Nevertheless, it is possible to detect EDTA if the acidity of the surface is controlled. The detection of EDTA-metal complexes is currently an open question, but evidence is presented for the detection of ions arising from a EDTA-lead complex. Carboxylic acids (i.e., citric, ascorbic, malic, succinic, malonic, and oxalic) give characteristic SIM spectra, but their detection on sample surfaces awaits evaluation.

Groenewold, G.S.; Applehans, A.D.; Ingram, J.C.; Delmore, J.E.; Dahl, D.A.

1993-01-01T23:59:59.000Z

70

Conformational Analysis of Disordered Proteins Using H/D Exchange Mass Spectrometry  

E-Print Network (OSTI)

Conformational Analysis of Disordered Proteins Using H/D Exchange Mass Spectrometry By Copyright 2013 Theodore Robert Keppel Submitted to the graduate degree program in Chemistry and the Graduate Faculty of the University of Kansas...: Conformational Analysis of Disordered Proteins Using H/D Exchange Mass Spectrometry ______________________________ Chairperson David Weis Date Approved: 02/01/2013 iii Abstract Intrinsically disordered proteins (IDPs...

Keppel, Theodore Robert

2013-05-31T23:59:59.000Z

71

High Mass Accuracy and High Mass Resolving Power FT-ICR Secondary Ion Mass Spectrometry for Biological Tissue Imaging  

SciTech Connect

Biological tissue imaging by secondary ion mass spectrometry has seen rapid development with the commercial availability of polyatomic primary ion sources. Endogenous lipids and other small bio-molecules can now be routinely mapped on the micrometer scale. Such experiments are typically performed on time-of-flight mass spectrometers for high sensitivity and high repetition rate imaging. However, such mass analyzers lack the mass resolving power to ensure separation of isobaric ions and the mass accuracy for exact mass elemental formula assignment. We have recently reported a secondary ion mass spectrometer with the combination of a C60 primary ion gun with a Fourier transform ion cyclotron resonance mass spectrometer (FT-ICR MS) for high mass resolving power, high mass measurement accuracy and tandem mass spectrometry capabilities. In this work, high specificity and high sensitivity secondary ion FT-ICR MS was applied to chemical imaging of biological tissue. An entire rat brain tissue was measured with 150 ?m spatial resolution (75 ?m primary ion spot size) with mass resolving power (m/?m50%) of 67,500 (at m/z 750) and root-mean-square measurement accuracy less than two parts-per-million for intact phospholipids, small molecules and fragments. For the first time, ultra-high mass resolving power SIMS has been demonstrated, with m/?m50% > 3,000,000. Higher spatial resolution capabilities of the platform were tested at a spatial resolution of 20 ?m. The results represent order of magnitude improvements in mass resolving power and mass measurement accuracy for SIMS imaging and the promise of the platform for ultra-high mass resolving power and high spatial resolution imaging.

Smith, Donald F.; Kiss, Andras; Leach, Franklin E.; Robinson, Errol W.; Pasa-Tolic, Ljiljana; Heeren, Ronald M.

2013-07-01T23:59:59.000Z

72

Time-of-Flight Secondary Ion Mass Spectrometry Based Molecular Histology of Human Spinal Cord Tissue and Motor Neurons  

Science Journals Connector (OSTI)

Secondary ion mass spectrometry is a powerful method for imaging biological samples with high spatial resolution. Whole section time-of-flight-secondary ion mass spectrometry (TOF-SIMS) scans and multivariate data analysis have been performed on the human ...

Jörg Hanrieder; Per Malmberg; Olle R. Lindberg; John S. Fletcher; Andrew G. Ewing

2013-08-15T23:59:59.000Z

73

Matrix Effects in Biological Mass Spectrometry Imaging: Identification and Compensation  

SciTech Connect

Matrix effects in mass spectrometry imaging (MSI) may affect the observed molecular distribution in chemical and biological systems. In this study, we introduce an experimental approach that efficiently compensates for matrix effects in nanospray desorption electrospray ionization (nano-DESI) MSI without introducing any complexity into the experimental protocol. We demonstrate compensation for matrix effects in nano-DESI MSI of phosphatidylcholine (PC) in normal and ischemic mouse brain tissue by doping the nano-DESI solvent with PC standards. Specifically, we use mouse brain tissue of a middle cerebral artery occlusion (MCAO) stroke model with an ischemic region localized to one hemisphere of the brain. Due to similar suppression in ionization of endogenous PC molecules extracted from the tissue and PC standards added to the solvent, matrix effects are eliminated by normalizing the intensity of the sodium and potassium adducts of endogenous PC to the intensity of the corresponding adduct of the PC standard. This approach efficiently compensates for signal variations resulting from differences in the local concentrations of sodium and potassium in tissue sections and from the complexity of the extracted analyte mixture derived from local variations in molecular composition.

Lanekoff, Ingela T.; Stevens, Susan; Stenzel-Poore, Mary; Laskin, Julia

2014-07-21T23:59:59.000Z

74

Detecting and Removing Data Artifacts in Hadamard Transform Ion Mobility-Mass Spectrometry Measurements  

Science Journals Connector (OSTI)

Applying Hadamard transform multiplexing to ion mobility separations (IMS) can significantly improve the signal-to-noise ratio and throughput for IMS coupled mass spectrometry (MS) measurements by increasing t...

Spencer A. Prost; Kevin L. Crowell…

2014-12-01T23:59:59.000Z

75

Colocalization of the Ganglioside GM1 and Cholesterol Detected by Secondary Ion Mass Spectrometry  

E-Print Network (OSTI)

here the use of secondary ion mass spectrometry (SIMS) to image the cholesterol-dependent cohesive of molecule specific images using a NanoSIMS. Simultaneous detection of six different ion species in SIMS

Boxer, Steven G.

76

Laser Ablation Inductively Coupled Plasma Mass Spectrometry Measurement of Isotope Ratios in Depleted Uranium Contaminated Soils  

Science Journals Connector (OSTI)

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...

Seltzer, Michael D

2003-01-01T23:59:59.000Z

77

Measurements of Volatile Organic Compounds Using Proton Transfer Reaction - Mass Spectrometry during the MILAGRO 2006 Campaign  

E-Print Network (OSTI)

Volatile organic compounds (VOCs) were measured by proton transfer reaction – mass spectrometry (PTR-MS) on a rooftop in the urban mixed residential and industrial area North Northeast of downtown Mexico City as part of ...

Fortner, E. C.

78

Rapid determination of 5-hydroxymethylfurfural by DART ionization with time-of-flight mass spectrometry  

Science Journals Connector (OSTI)

DART (direct analysis in real time), a novel technique with wide potential for rapid screening analysis, coupled with high-resolution time-of-flight mass spectrometry (TOF-MS) has been used for quantitative analy...

Aleš Rajchl; Ladislava Drgová; Adéla Grégrová…

2013-05-01T23:59:59.000Z

79

Determination of trace impurities in zircaloy-2 and tellurium by spark source mass spectrometry  

Science Journals Connector (OSTI)

Determination of trace impurities in zircaloy-2 and tellurium by Spark Source Mass Spectrometry (SSMS) is reported. The advantage of SSMS lies in the fact that along with metallic trace constituents even the n...

K. L. Ramakumar; V. A. Raman; V. L. Sant…

1988-12-01T23:59:59.000Z

80

Systematic Optimization of Long Gradient Chromatography Mass Spectrometry for Deep Analysis of Brain Proteome  

Science Journals Connector (OSTI)

The development of high-resolution liquid chromatography (LC) is essential for improving the sensitivity and throughput of mass spectrometry (MS)-based proteomics. Here we present systematic optimization of a long gradient LC–MS/MS platform to enhance ...

Hong Wang; Yanling Yang; Yuxin Li; Bing Bai; Xusheng Wang; Haiyan Tan; Tao Liu; Thomas G. Beach; Junmin Peng; Zhiping Wu

2014-12-02T23:59:59.000Z

Note: This page contains sample records for the topic "accelerator mass spectrometry" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Cluster ion formation during sputtering processes: a complementary investigation by ToF-SIMS and plasma ion mass spectrometry  

Science Journals Connector (OSTI)

Plasma ion mass spectrometry using a plasma process monitor (PPM) and time-of-flight secondary ion mass spectrometry (ToF-SIMS) have been complementarily employed to investigate the sputtering and ion formation processes of Al-doped zinc oxide. By comparing the mass spectra, insights on ion formation and relative cross-sections have been obtained: positive ions as measured during magnetron sputtering by PPM are originating from the plasma while those in SIMS start at the surface leading to large differences in the mass spectra. In contrast, negative ions originating at the surface will be accelerated through the plasma sheath. They arrive at the PPM after traversing the plasma nearly collisionless as seen from the rather similar spectra. Hence, it is possible to combine the high mass resolution of ToF-SIMS to obtain insight for separating cluster ions, e.g. Znx and ZnOy, and the energy resolution of PPM to find fragmentation patterns for negative ions. While the ion formation processes during both experiments can be assumed to be similar, differences may arise due to the lower volume probed by SIMS. In the latter case, there is a chance of small target inhomogeneities being able to be enhanced and lower surface temperatures leading to less outgassing and, thus, retention of volatile compounds.

T Welzel; S Mändl; K Ellmer

2014-01-01T23:59:59.000Z

82

RAPID DETERMINATION OF 237 NP AND PU ISOTOPES IN WATER BY INDUCTIVELY COUPLED PLASMA MASS SPECTROMETRY AND ALPHA SPECTROMETRY  

SciTech Connect

A new method that allows rapid preconcentration and separation of plutonium and neptunium in water samples was developed for the measurement of {sup 237}Np and Pu isotopes by inductively-coupled plasma mass spectrometry (ICP-MS) and alpha spectrometry; a hybrid approach. {sup 238}U can interfere with {sup 239}Pu measurement by ICP-MS as {sup 238}UH{sup +} mass overlap and {sup 237}Np via peak tailing. The method provide enhanced removal of uranium by separating Pu and Np initially on TEVA Resin, then moving Pu to DGA resin for additional removal of uranium. The decontamination factor for uranium from Pu is almost 100,000 and the decontamination factor for U from Np is greater than 10,000. This method uses stacked extraction chromatography cartridges and vacuum box technology to facilitate rapid separations. Preconcentration is performed using a streamlined calcium phosphate precipitation method. Purified solutions are split between ICP-MS and alpha spectrometry so that long and short-lived Pu isotopes can be measured successfully. The method allows for simultaneous extraction of 20 samples (including QC samples) in 4 to 6 hours, and can also be used for emergency response. {sup 239}Pu, {sup 242}Pu and {sup 237}Np were measured by ICP-MS, while {sup 236}Pu, {sup 238}Pu, and {sup 239}Pu were measured by alpha spectrometry.

Maxwell, S.; Jones, V.; Culligan, B.; Nichols, S.; Noyes, G.

2010-06-23T23:59:59.000Z

83

Novel mass spectrometry mutation screening for contaminant impact analysis. 1998 annual progress report  

SciTech Connect

'The objective is to develop innovative mass spectrometry technology to achieve fast mutation screening from contaminated area and to reveal the linkage between gene mutation and contaminants. In this program, the author will try innovative approaches to improve mass resolution and detection efficiency for large DNA ions. Allel specific polymerase chain reaction will be coupled with mass spectrometry for rapid DNA mutation detection. The ultimate goal is to lead to the risk analysis of hazardous wastes to be routinely assessed at DNA level at an affordable cost. This report is for the work after 7 months of a 3-year project.'

Chen, C.H.

1998-06-01T23:59:59.000Z

84

Spatial Querying of Imaging Mass Spectrometry Data for the Biochemical Characterization of Anatomical Regions in Tissue  

E-Print Network (OSTI)

Spatial Querying of Imaging Mass Spectrometry Data for the Biochemical Characterization tissue section. In this paper we develop methods that enable spatial querying of MSI data. The objective that adds spatial information to mass spectral biochemical analysis. It delivers insight into the spatial

85

Automation of Solid-Phase Microextraction-Gas Chromatography-Mass Spectrometry Extraction of Eucalyptus Volatiles  

Science Journals Connector (OSTI)

......Eucalyptus metabolism Gas Chromatography-Mass...SPME) coupled with gas chromatography (GC...processes involved in the production, emission, and effects...Solid-Phase Microextraction Gas ChromatographyMass Spectrometry...significant savings in time and cost could be realized. In......

Cláudia A. Zini; III; Heather Lord; Eva Christensen; Teotônio F. de Assis; Elina B. Caramão; Janusz Pawliszyn

2002-03-01T23:59:59.000Z

86

On-line electrochemistry/electrospray mass spectrometry: Studies of oxidation of polycyclic aromatic hydrocarbons (PAHs)  

SciTech Connect

Studies of on-line coupling of electrochemistry with mass spectrometry, i.e., {open_quotes}electrochemical mass spectrometry{close_quotes} (EC/MS) date back to work by Bruckenstein et al. in the 1970`s. In these and other early experiments, porous working electrodes or permeable membranes were usually used as the interface between the cell and the MS ionization source which exclusively employed electron ionization (EI). As a result, only volatile products of electrochemical reactions could be detected by the mass line electrochemistry/mass spectroscopy was the coupling of an mass spectrometer (EC/TS/MS) reported by Hambitzer and g an aqueous ammonium acetate thermospray buffer solution, all detected or ammoniated species in the positive ion mode or as deprotonated or acetate adduct species in the negative ion mode. Radical cations or anions were not detected. Although {open_quotes}electrochemically assisted electrospray mass spectrometry{close_quotes} has been progressing for a few years, chiefly due to the pioneering efforts of Van Berkel and coworkers, on-line coupling electrochemistry with electrospray mass spectrometry (EC/ESMS) is still a developing area because of the experimental difficulties involved, such as high voltage hazard to the electrochemistry hardware (e.g. potentiostat), and MS signal suppression caused by the presence of high concentrations of supporting electrolytes. We report the coupling of an electrochemical device on-line with electrospray mass spectrometry (EC/ESMS) to extend the potential of ESMS to detect non-polar neutral compounds, and to monitor and identify intermediates and products generated by electrochemical reactions.

Xu, Xiaoming; Lu, Wenzhe; Cole, R.B. [Univ. of New Orleans, LA (United States)] [and others

1995-12-31T23:59:59.000Z

87

Apparatus and methods for continuous beam fourier transform mass spectrometry  

DOE Patents (OSTI)

A continuous beam Fourier transform mass spectrometer in which a sample of ions to be analyzed is trapped in a trapping field, and the ions in the range of the mass-to-charge ratios to be analyzed are excited at their characteristic frequencies of motion by a continuous excitation signal. The excited ions in resonant motions generate real or image currents continuously which can be detected and processed to provide a mass spectrum.

McLuckey, Scott A. (Oak Ridge, TN); Goeringer, Douglas E. (Oak Ridge, TN)

2002-01-01T23:59:59.000Z

88

C3Bio.org - Tags: Mass Spectrometry Data  

NLE Websites -- All DOE Office Websites (Extended Search)

Dave J Borton, Hilkka Inkeri Kenttamaa Developments in atmospheric pressure ionization (API) techniques have revolutionized the mass spectrometric analysis of large and...

89

RAPID DETERMINATION OF ACTINIDES IN URINE BY INDUCTIVELY-COUPLED PLASMA MASS SPECTROMETRY AND ALPHA SPECTROMETRY: A HYBRID APPROACH  

SciTech Connect

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. Multiple vacuum box locations may be set-up to supply several ICP-MS units with purified sample fractions such that a high sample throughput may be achieved, while still allowing for rapid measurement of short-lived actinides by alpha spectrometry.

Maxwell, S.; Jones, V.

2009-05-27T23:59:59.000Z

90

Review of Mass Spectrometry–Based Metabolomics in Cancer Research  

Science Journals Connector (OSTI)

...155-71. 2. Oliver SG , Winson MK, Kell DB, Baganz F.Systematic...hepatocellular carcinoma patients by ultra performance liquid chromatography-mass...hydroxylated, polyunsaturated ultra long-chain fatty acids in...performance liquid chromatography and ultra performance liquid chromatography-mass...

David B. Liesenfeld; Nina Habermann; Robert W. Owen; Augustin Scalbert; and Cornelia M. Ulrich

2013-12-01T23:59:59.000Z

91

Noise reduction in negative-ion quadrupole mass spectrometry  

DOE Patents (OSTI)

A quadrupole mass spectrometer (QMS) system having an ion source, quadrupole mass filter, and ion collector/recorder system. A weak, transverse magnetic field and an electron collector are disposed between the quadrupole and ion collector. When operated in negative ion mode, the ion source produces a beam of primarily negatively-charged particles from a sample, including electrons as well as ions. The beam passes through the quadrupole and enters the magnetic field, where the electrons are deflected away from the beam path to the electron collector. The negative ions pass undeflected to the ion collector where they are detected and recorded as a mass spectrum.

Chastagner, Philippe (3134 Natalie Cir., Augusta, GA 30909-2748)

1993-01-01T23:59:59.000Z

92

Department of Chemistry Mass Spectrometry Sample Submission Form  

E-Print Network (OSTI)

's ID. · You are responsible to pick up your samples within 7 days after the analysis. · Please call 801: [ ] Standard (LRMS) [ ] Exact Mass (HRMS) Ionization type: [ ] ESI [ ] MALDI [ ] EI (GC/MS only) Scans required

Simons, Jack

93

Secondary Ion Mass Spectrometry Imaging of Dictyostelium discoideum...  

NLE Websites -- All DOE Office Websites (Extended Search)

to enable this. In this report, we employed Bi3 bombardment time-of-flight (Bi3 ToF-SIMS) and C60 bombardment Fourier transform ion cyclotron resonance secondary ion mass...

94

Single cancer cell imaging and cell extract analysis using time-of-flight secondary ion mass spectrometry (TOF-SIMS)  

Science Journals Connector (OSTI)

...secondary ion mass spectrometry (TOF-SIMS) Kristen S. Kulp Kuang J. Wu David L...Secondary Ion Mass Spectrometry (TOF-SIMS) to image and identify individual cells...A surface scanning procedure, TOF-SIMS is uniquely suited to the sensitive detection...

Kristen S. Kulp; Kuang J. Wu; David L. Shattuck; Ligang Wu; Erik J. Nelson; Jennifer L. Montgomery; James S. Felton; Mark G. Knize

2005-05-01T23:59:59.000Z

95

Composition of nanoparticles in optical fibers by Secondary Ion Mass Spectrometry  

E-Print Network (OSTI)

encapsulate LI to produce « engineered » spectroscopic properties. To determine the composition of DNP-SIMS investigation of boron distribution in steels," Surf. Interface Anal. 43, 573-575 (2011). 12. C. Lechene, F imaging of mammalian and bacterial cells using stable isotope mass spectrometry," Journal of Biology 5, 20

Boyer, Edmond

96

Tandem Mass Spectrometry for the Direct Assay of Lysosomal Enzymes in  

E-Print Network (OSTI)

. Mucopolysaccharidosis type I (MPS-I)4 is a lysosomal storage disorder caused by the deficiency of -L- iduronidase (Id-Scheie syndromes. IdA is essential for the degradation within lysosomes of the glycosamino- glycans dermatan recognition of MPS-I. Flu- orometric, radiometric, and electrospray ionization­ tandem mass spectrometry (ESI

Gelb, Michael

97

FOCUS: HARSH ENVIRONMENT MASS SPECTROMETRY Field Testing of Lake Water Chemistry with a  

E-Print Network (OSTI)

FOCUS: HARSH ENVIRONMENT MASS SPECTROMETRY Field Testing of Lake Water Chemistry with a Portable waters. KOALA is a backpackable MS operated from above the water surface, in which samples are pumped for temperature control of a membrane inlet when steep thermal gradients are present in a water body, as well

Entekhabi, Dara

98

Visual Steering and Verification of Mass Spectrometry Data Factorization in Air Quality Research  

E-Print Network (OSTI)

quality research involves the analysis of high-dimensional single particle mass spectrometry data. We data at significantly increased speed and a higher degree of ease. Index Terms--Dimension reduction of numerical error metrics, multi-dimensional data visualization. 1 INTRODUCTION Atmospheric particles increase

Hamann, Bernd

99

Desorption Electrospray Ionization Mass Spectrometry for Trace Analysis of Agrochemicals in Food  

Science Journals Connector (OSTI)

Desorption Electrospray Ionization Mass Spectrometry for Trace Analysis of Agrochemicals in Food ... Desorption electrospray ionization (DESI) is applied to the rapid, in situ, direct qualitative and quantitative (ultra)trace analysis of agrochemicals in foodstuffs. ... The results proved that DESI allows the detection and confirmation of traces of agrochemicals in actual market-purchased samples. ...

Juan F. García-Reyes; Ayanna U. Jackson; Antonio Molina-Díaz; R. Graham Cooks

2008-12-17T23:59:59.000Z

100

Apparatus and method for hydrogen and oxygen mass spectrometry of the terrestrial magnetosphere  

DOE Patents (OSTI)

A detector element for mass spectrometry of a flux of heavy and light ions, that includes: a first detector to detect light ions that transit through a foil operatively placed in front of the first detector, and a second detector that detects the flux of heavy and light ions.

Funsten, Herbert O. (Los Alamos, NM); Dors, Eric E. (Los Alamos, NM); Harper, Ronnie W. (Los Alamos, NM); Reisenfeld, Daniel B. (Stevensville, MT)

2007-05-15T23:59:59.000Z

Note: This page contains sample records for the topic "accelerator mass spectrometry" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

Apparatus for preparing a sample for mass spectrometry  

DOE Patents (OSTI)

An apparatus is described for preparing a sample for analysis by a mass spectrometer system. The apparatus has an entry chamber and an ionization chamber separated by a skimmer. A capacitor having two space-apart electrodes followed by one or more ion-imaging lenses is disposed in the ionization chamber. The chamber is evacuated and the capacitor is charged. A valve injects a sample gas in the form of sample pulses into the entry chamber. The pulse is collimated by the skimmer and enters the ionization chamber. When the sample pulse passes through the gap between the electrodes, it discharges the capacitor and is thereby ionized. The ions are focused by the imaging lenses and enter the mass analyzer, where their mass and charge are analyzed. 1 figures.

Villa-Aleman, E.

1994-05-10T23:59:59.000Z

102

OpenMSI: A High-Performance Web-Based Platform for Mass Spectrometry Imaging  

SciTech Connect

Mass spectrometry imaging (MSI) enables researchers to directly probe endogenous molecules directly within the architecture of the biological matrix. Unfortunately, efficient access, management, and analysis of the data generated by MSI approaches remain major challenges to this rapidly developing field. Despite the availability of numerous dedicated file formats and software packages, it is a widely held viewpoint that the biggest challenge is simply opening, sharing, and analyzing a file without loss of information. Here we present OpenMSI, a software framework and platform that addresses these challenges via an advanced, high-performance, extensible file format and Web API for remote data access (http://openmsi.nersc.gov). The OpenMSI file format supports storage of raw MSI data, metadata, and derived analyses in a single, self-describing format based on HDF5 and is supported by a large range of analysis software (e.g., Matlab and R) and programming languages (e.g., C++, Fortran, and Python). Careful optimization of the storage layout of MSI data sets using chunking, compression, and data replication accelerates common, selective data access operations while minimizing data storage requirements and are critical enablers of rapid data I/O. The OpenMSI file format has shown to provide >2000-fold improvement for image access operations, enabling spectrum and image retrieval in less than 0.3 s across the Internet even for 50 GB MSI data sets. To make remote high-performance compute resources accessible for analysis and to facilitate data sharing and collaboration, we describe an easy-to-use yet powerful Web API, enabling fast and convenient access to MSI data, metadata, and derived analysis results stored remotely to facilitate high-performance data analysis and enable implementation of Web based data sharing, visualization, and analysis.

Rubel, Oliver; Greiner, Annette; Cholia, Shreyas; Louie, Katherine; Bethel, E. Wes; Northen, Trent R.; Bowen, Benjamin P.

2013-10-02T23:59:59.000Z

103

²?²Cf-plasma desorption mass spectrometry of RNA nucleosides  

E-Print Network (OSTI)

~ CH5 + CH3 CH3 + CH4 ~ C2H5 + H2 Proton or hydride transfer reactions of these secondary ions with the sample molecule produce the major portion of the CI mass spectra. Because the molecular ions are formed by these chemical reactions... low, and co'1'lisional deactivation between sample fons and air molecules results in a loss of intensity and resolution for the sample ions detected. -7 The vacuum in the mass spectrometer is maintained in the 10 16 torr region by a Sargent...

Piper, Duane Gilbert

1976-01-01T23:59:59.000Z

104

High explosives vapor detection by atmospheric sampling glow discharge ionization/tandem mass spectrometry  

SciTech Connect

The combination of atmospheric sampling glow discharge ionization with tandem mass spectrometry for the detection of traces of high explosives is described. Particular emphasis is placed on use of the quadrupole ion trap as the type of tandem mass spectrometer. Atmospheric sampling glow discharge provides a simple, rugged, and efficient means for anion formation while the quadrupole ion trap provides for efficient tandem mass spectrometry. Mass selective ion accumulation and non-specific ion activation methods can be used to overcome deleterious effects arising from ion/ion interactions. Such interactions constitute the major potential technical barrier to the use of the ion trap for real-time monitoring of targeted compounds in uncontrolled and highly variable matrices. Tailored waveforms can be used to effect both mass selective ion accumulation and ion activation. Concatenated tailored waveforms allow for both functions in a single experiment thereby providing the capability for monitoring several targeted species simultaneously. The combination of atmospheric sampling glow discharge ionization with a state-of-the-art analytical quadrupole ion trap is a highly sensitive and specific detector for traces of high explosives. The combination is also small and inexpensive relative to virtually any other form of tandem mass spectrometry. The science and technology underlying the glow discharge/ion trap combination is sufficiently mature to form the basis for an engineering effort to make the detector portable. 85 refs.

McLuckey, S.A.; Goeringer, D.E.; Asano, K.G. [Oak Ridge National Lab., TN (United States). Chemical and Analytical Sciences Div.

1996-02-01T23:59:59.000Z

105

Evaluation of Hypervelocity Gold Nanoparticles for Nanovolume Surface Mass Spectrometry  

E-Print Network (OSTI)

in Figure VI-1 ................................................................................................ 166 VI-3 SI yields for samples containing various amounts of silver and gold on top of a PMMA film analyzed by massive gold clusters... and Bi+ ........ 169 VI-4 Negative mode mass spectrum from atomic-SIMS analysis of a PMMA surface ........................................................................................... 170 VI-5 Proposed structures for fragment ions...

DeBord, John 1986-

2012-08-16T23:59:59.000Z

106

National Centre for Biological Sciences Mass Spectrometry Facility  

E-Print Network (OSTI)

: Sample Information Number of samples: Sample ID: Concentration: Solubility: Expected mass (Da): Molecular: Protein Peptide Lipid Nucleic acid Others (specify) Analysis Requirement ESI MS, low resolution ESI MS, high resolution LC-ESI MS LC-ESI MS/MS Others (specify) Signature of research supervisor: Signature

Bhalla, Upinder S.

107

Explanatory Optimization of Protein Mass Spectrometry via Genetic Search  

E-Print Network (OSTI)

of the mass spectrometer settings that accounts for much of this success. Specifically, the conditions of Wales, Aberystwyth, Ceredigion SY23 3DD, U.K. Optimizing experimental conditions for the effective analy that little or no a priori knowledge of the optimal conditions is available. There is much current interest

Fernandez, Thomas

108

Coulomb crystal mass spectrometry in a digital ion trap  

E-Print Network (OSTI)

We present a mass spectrometric technique for identifying the masses and relative abundances of Coulomb-crystallized ions held in a linear Paul trap. A digital radiofrequency waveform is employed to generate the trapping potential, as this can be cleanly switched off, and static dipolar fields subsequently applied to the trap electrodes for ion ejection. Excellent detection efficiency is demonstrated for Ca+ and CaF+ ions from bi-component Ca+/CaF+ Coulomb crystals prepared by reaction of Ca+ with CH3F. A quantitative linear relationship is observed between ion number and the corresponding integrated TOF peak, independent of the ionic species. The technique is applicable to a diverse range of multi-component Coulomb crystals - demonstrated here for Ca+/NH3+/NH4+ and Ca+/CaOH+/CaOD+ crystals - and will facilitate the measurement of ion-molecule reaction rates and branching ratios in complicated reaction systems.

Deb, Nabanita; Smith, Alexander D; Keller, Matthias; Rennick, Christopher J; Heazlewood, Brianna R; Softley, Timothy P

2015-01-01T23:59:59.000Z

109

Plume collimation for laser ablation electrospray ionization mass spectrometry  

DOE Patents (OSTI)

In various embodiments, a device may generally comprise a capillary having a first end and a second end; a laser to emit energy at a sample in the capillary to ablate the sample and generate an ablation plume in the capillary; an electrospray apparatus to generate an electrospray plume to intercept the ablation plume to produce ions; and a mass spectrometer having an ion transfer inlet to capture the ions. The ablation plume may comprise a collimated ablation plume. The device may comprise a flow cytometer. Methods of making and using the same are also described.

Vertes, Akos; Stolee, Jessica A.

2014-09-09T23:59:59.000Z

110

A simple algorithm improves mass accuracy to 50-100 ppm for delayed extraction linear MALDI-TOF mass spectrometry  

SciTech Connect

A simple mathematical technique for improving mass calibration accuracy of linear delayed extraction matrix assisted laser desorption ionization time-of-flight mass spectrometry (DE MALDI-TOF MS) spectra is presented. The method involves fitting a parabola to a plot of Dm vs. mass data where Dm is the difference between the theoretical mass of calibrants and the mass obtained from a linear relationship between the square root of m/z and ion time of flight. The quadratic equation that describes the parabola is then used to correct the mass of unknowns by subtracting the deviation predicted by the quadratic equation from measured data. By subtracting the value of the parabola at each mass from the calibrated data, the accuracy of mass data points can be improved by factors of 10 or more. This method produces highly similar results whether or not initial ion velocity is accounted for in the calibration equation; consequently, there is no need to depend on that uncertain parameter when using the quadratic correction. This method can be used to correct the internally calibrated masses of protein digest peaks. The effect of nitrocellulose as a matrix additive is also briefly discussed, and it is shown that using nitrocellulose as an additive to a CHCA matrix does not significantly change initial ion velocity but does change the average position of ions relative to the sample electrode at the instant the extraction voltage is applied.

Hack, Christopher A.; Benner, W. Henry

2001-10-31T23:59:59.000Z

111

Direct analysis of cellulose in poplar stem by matrixassisted laser desorption/ionization imaging mass spectrometry  

NLE Websites -- All DOE Office Websites (Extended Search)

analysis analysis of cellulose in poplar stem by matrix- assisted laser desorption/ionization imaging mass spectrometry Seokwon Jung 1,3 , Yanfeng Chen 3 , M. Cameron Sullards 1,3 and Arthur J. Ragauskas 1,2,3 * 1 BioEnergy Science Center, Georgia Institute of Technology, 500 10 th St., Atlanta, GA 30332, USA 2 Institute of Paper Science and Technology, Georgia Institute of Technology, 500 10 th St., Atlanta, GA 30332, USA 3 School of Chemistry and Biochemistry, Georgia Institute of Technology, 901 Atlantic Drive, Atlanta, GA 30332, USA Received 10 July 2010; Revised 9 August 2010; Accepted 23 August 2010 Matrix-assisted laser desorption/ionization imaging mass spectrometry (MALDI-IMS) was applied to the analysis of the spatial distribution of cellulose on a cross-section of juvenile poplar (Populus deltoids) stems. Microcrystalline cellulose (MCC) was used to optimize matrix (2,5-dihydroxybenzoic

112

Fundamentals and Applications of Electrospray Ionization Mass Spectrometry for Petroleum Characterization  

Science Journals Connector (OSTI)

Fundamentals and Applications of Electrospray Ionization Mass Spectrometry for Petroleum Characterization ... We are reporting a study of the fundamental and application aspects of positive-ion electrospray ionization (ESI+) for petroleum characterization. ... The gas-phase basicities (GBs) were experimental data from the NIST Chemistry WebBook,33 whereas the aqueous basicities (pKb) were derived from Lange's Handbook of Chemistry, 14th Edition. ...

Kuangnan Qian; Kathleen E. Edwards; John H. Diehl; Larry A. Green

2004-09-10T23:59:59.000Z

113

2?52Cf plasma desorption mass spectrometry of metal clusters  

E-Print Network (OSTI)

August 1991 Major Subject: Chemistry s Cf PLASMA DESORPTION MASS SPECTROMETRY OF METAL CLUSTERS A Thesis by JANITA MURIEL HUGHES Approved as to style and content by: R. D. ac ane (Chair of Co 'uee) J. P. Fac er (Member) A. . aray (Member) M... and negative ion spectra. However, close-packed complexes like [Pt (CO), g" form cluster cor- responding to the oligomeric species, [(Pt ), (CO)?], from n=2 to n=20. The latter structure contains 520 platinum atoms with an observed mass in excess of m/z 100...

Hughes, Janita Muriel

1991-01-01T23:59:59.000Z

114

Gas chromatography–mass spectrometry analysis of fatty acid profiles of Antarctic and non-Antarctic yeasts  

Science Journals Connector (OSTI)

The fatty acid profiles of Antarctic (n = 7) and non-Antarctic yeasts (n = 7) grown at different temperatures were analysed by gas chromatography–mass spectrometry. The Antarctic yeasts were enriched in oleic 18:...

Mohammad Bhuiyan; David Tucker; Kenneth Watson

2014-08-01T23:59:59.000Z

115

A high selective and sensitive liquid chromatography–tandem mass spectrometry method for quantization of BPA urinary levels in children  

Science Journals Connector (OSTI)

A selective and highly sensitive liquid chromatography–tandem mass spectrometry method has been developed and validated for determination of Bisphenol A (BPA) in human urine using labeled d6-BPA as internal stand...

Carla Nicolucci; Sergio Rossi; Ciro Menale…

2013-11-01T23:59:59.000Z

116

Automatic Gain Control in Mass Spectrometry using a Jet Disrupter Electrode in an Electrodynamic Ion Funnel  

SciTech Connect

We report on the use of a jet disrupter electrode in an electrodynamic ion funnel as an electronic valve to regulate the intensity of the ion beam transmitted through the interface of a mass spectrometer in order to perform automatic gain control (AGC). The ion flux is determined by either directly detecting the ion current on the conductance limiting orifice of the ion funnel or using a short mass spectrometry acquisition. Based upon the ion flux intensity, the voltage of the jet disrupter is adjusted to alter the transmission efficiency of the ion funnel to provide a desired ion population to the mass analyzer. Ion beam regulation by an ion funnel is shown to provide an unbiased control to within a few percent of a targeted ion intensity or abundance. The utility of ion funnel AGC was evaluated using a protein tryptic digest analyzed with liquid chromatography Fourier transform ion cyclotron resonance (LC-FTICR) mass spectrometry. The ion population in the ICR cell was accurately controlled to a variety of different levels, which improved data quality and provided better mass measurement accuracy.

Page, Jason S.; Bogdanov, Bogdan; Vilkov, Andrey N.; Prior, David C.; Buschbach, Michael A.; Tang, Keqi; Smith, Richard D.

2005-02-01T23:59:59.000Z

117

Development of New Soft Ionization Mass Spectrometry Approaches for Spatial Imaging of Complex Chemical and Biological Systems  

E-Print Network (OSTI)

world's first C60 SIMS FT-ICR MS. Unique capabilities for imaging biological samples: High mass accuracy spatial resolution (~10 µm) High spatial and mass resolution C60 secondary ion mass spectrometry (SIMS of the colony Conducted first multimodal imaging of biological materials using nano-DESI, SIMS, and matrix

118

Nanoelectrospray ion generation for high-throughput mass spectrometry using a micromachined ultrasonic ejector array  

SciTech Connect

Ultrasonic electrospray ionization (ESI) for high-throughput mass spectrometry is demonstrated using a silicon micromachined microarray. The device uses a micromachined ultrasonic atomizer operating in the 900 kHz-2.5 MHz range for droplet generation and a metal electrode in the fluid cavity for ionization. Since the atomization and ionization processes are separated, the ultrasonic ESI source shows the potential for operation at low voltages with a wide range of solvents in contrast with conventional capillary ESI technology. This is demonstrated using the ultrasonic ESI microarray to obtain the mass spectrum of a 10 {mu}M reserpine sample on a time of flight mass spectrometer with 197:1 signal-to-noise ratio at an ionization potential of 200 V.

Aderogba, S.; Meacham, J.M.; Degertekin, F.L.; Fedorov, A.G.; Fernandez, F.M. [G.W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332 (United States); School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332 (United States)

2005-05-16T23:59:59.000Z

119

Elemental and isotopic analysis of inorganic salts by laser desorption ionization mass spectrometry  

SciTech Connect

Laser desorption ionization mass spectrometry is applied for the analysis of elements as well as their isotopic composition in different inorganic salts. At very low laser energies the inorganic ions are desorbed and ionized from the thin layer of the sample surface. The naturally occurring isotopes of alkali and silver ions are resolved using time of flight mass spectrometer. Further increase in laser energy shows the appearance of Al, Cr, and Fe ions in the mass spectra. This indicates the penetration laser beam beyond the sample surface leading to the ablation of sample target at higher energies. The simultaneous appearance of atomic ions from the sample target at relatively higher laser energies hampers the unambiguous identification of amino acid residues from the biomolecular ions in MALDI-MS.

Jayasekharan, T.; Sahoo, N. K. [Applied Spectroscopy Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India)

2013-02-05T23:59:59.000Z

120

Monitoring Genetic and Metabolic Potential for In-Site Bioremediation: Mass Spectrometry  

SciTech Connect

A number of DOE sites are contaminated with mixtures of dense non-aqueous phase liquids (DNAPLs) such as carbon tetrachloride, chloroform, perchloroethylene, and trichloroethylene. At many of these sites, in situ microbial bioremediation is an attractive strategy for cleanup, since it has the potential to degrade DNAPLs in situ without the need for pump-and-treat or soil removal procedures, and without producing toxic byproducts. A rapid screening method to determine broad range metabolic and genetic potential for contaminant degradation would greatly reduce the cost and time involved in assessment for in situ bioremediation, as well as for monitoring ongoing bioremediation treatment. The objective of this project was the development of mass-spectrometry-based methods to screen for genetic potential for both assessment and monitoring of in situ bioremediation of DNAPLs. These methods were designed to provide more robust and routine methods for DNA-based characterization of the genetic potential of subsurface microbes for degrading pollutants. Specifically, we sought to (1) Develop gene probes that yield information equivalent to conventional probes, but in a smaller size that is more amenable to mass spectrometric detection, (2) Pursue improvements to matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) methodology in order to allow its more general application to gene probe detection, and (3) Increase the throughput of microbial characterization by integrating gene probe preparation, purification, and MALDI-MS analysis.

Buchanan, M.V.

2000-07-20T23:59:59.000Z

Note: This page contains sample records for the topic "accelerator mass spectrometry" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

Using electrospray ionization FTICR mass spectrometry to study competitive binding of inhibitors to carbonic anhydrase  

SciTech Connect

We report a method based on mass spectrometry for the characterization of noncovalent complexes of proteins with mixtures of ligands; this method is relevant to the study of drug leads and may be useful in screening libraries for tight-binding compounds. This study describes the competitive binding of inhibitors derived from para-substituted benzenesulfonamides to bovine carbonic anhydrase II (BCAII, EC 4.2.1.1) using this technique. Relative binding constants and structural information for a mixture of inhibitors can be obtained in a single experiment using ESI-FTICR-MS. The work demonstrates that ESI-MS has significant potential for measuring relative binding affinities and characterizing the structures of ligands associated noncovalently to proteins. We have detected noncovalent complexes in the gas phase for ligands having values of K{sub b} as low as 1.7 x 10{sup 6} M{sup -1} in solution. The technique also allowed identification of tightbinding ligands from small libraries. The structures of inhibitors having similar masses can be identified by the high-resolution and multistep dissociation mass spectrometry of which FTICR is uniquely capable. This range of capabilities for ESI-FTICR-MS should be widely useful in medicinal chemistry. 22 refs., 2 figs.

Cheng, X.; Chen, R.; Bruce, J.E.; Schwartz, B.L.; Anderson, G.A.; Hofstadler, S.A.; Gale, D.C.; Smith, R.D. [Pacific Northwest Lab., Richland, WA (United States); Gao, J.; Sigal, G.B.; Mammen, M.; Whitesides, G.M. [Harvard Univ., Cambridge, MA (United States)

1995-08-30T23:59:59.000Z

122

VUV photoionization time-of-flight mass spectrometry of flash pyrolysis of silane and disilane  

Science Journals Connector (OSTI)

Flash pyrolysis of silane, SiH4, and disilane, Si2H6, diluted in He or Ar (1%), was carried out at temperatures ranging from ?700 to ?1500 K. After a short reaction time of ?20 ?s, the initial products were isolated in a supersonic molecular beam and detected by single vacuum ultra-violet (VUV) photon (?=118 or 121 nm) ionization time-of-flight mass spectrometry (TOFMS). Initial decomposition and reaction products, both free radical intermediates and stable species, were directly observed, which included SiH2 and Si2H4.

Steven D. Chambreau; Jingsong Zhang

2001-01-01T23:59:59.000Z

123

Toward Single-Cell Analysis by Plume Collimation in Laser Ablation Electrospray Ionization Mass Spectrometry  

Science Journals Connector (OSTI)

In the plume collimation experiments, laser radiation was delivered through a germanium oxide (GeO2) optical fiber (450 ?m core diameter, HP Fiber, Infrared Fiber Systems, Inc., Silver Spring, MD) with a tip etched in a 2% nitric acid solution as described earlier. ... Upon ablation in the capillary, a collimated plume emerges (shown in blue) and is ionized by an electrospray. ... Individual sea urchin eggs were selected by using the micromanipulator system and deposited into a capillary for LAESI mass spectrometry with plume collimation. ...

Jessica A. Stolee; Akos Vertes

2013-02-28T23:59:59.000Z

124

Ultra-high-mass mass spectrometry with charge discrimination using cryogenic detectors  

DOE Patents (OSTI)

An ultra-high-mass time-of-flight mass spectrometer using a cryogenic particle detector as an ion detector with charge discriminating capabilities. Cryogenic detectors have the potential for significantly improving the performance and sensitivity of time-of-flight mass spectrometers, and compared to ion multipliers they exhibit superior sensitivity for high-mass, slow-moving macromolecular ions and can be used as "stop" detectors in time-of-flight applications. In addition, their energy resolving capability can be used to measure the charge state of the ions. Charge discrimination is very valuable in all time-of-flight mass spectrometers. Using a cryogenically-cooled Nb-Al.sub.2 O.sub.3 -Nb superconductor-insulator-superconductor (SIS) tunnel junction (STJ) detector operating at 1.3 K as an ion detector in a time-of-flight mass spectrometer for large biomolecules it was found that the STJ detector has charge discrimination capabilities. Since the cryogenic STJ detector responds to ion energy and does not rely on secondary electron production, as in the conventionally used microchannel plate (MCP) detectors, the cryogenic detector therefore detects large molecular ions with a velocity-independent efficiency approaching 100%.

Frank, Matthias (Berkeley, CA); Mears, Carl A. (Oakland, CA); Labov, Simon E. (Berkeley, CA); Benner, W. Henry (Danville, CA)

1999-01-01T23:59:59.000Z

125

A Mass Spectrometry Study of Isotope Separation in the Laser Plume  

E-Print Network (OSTI)

1.4.2 Atomic Absorption5.3.2 Atomic Absorption Spectrometry . . . . . . . . . . .ablation and diode laser-atomic absorption spectrometry”,

Suen, Timothy Wu

2012-01-01T23:59:59.000Z

126

RELATION BETWEEN THE CORONAL MASS EJECTION ACCELERATION AND THE NON-THERMAL FLARE CHARACTERISTICS  

SciTech Connect

We investigate the relationship between the main acceleration phase of coronal mass ejections (CMEs) and the particle acceleration in the associated flares as evidenced in Reuven Ramaty High Energy Solar Spectroscopic Imager non-thermal X-rays for a set of 37 impulsive flare-CME events. Both the CME peak velocity and peak acceleration yield distinct correlations with various parameters characterizing the flare-accelerated electron spectra. The highest correlation coefficient is obtained for the relation of the CME peak velocity and the total energy in accelerated electrons (c = 0.85), supporting the idea that the acceleration of the CME and the particle acceleration in the associated flare draw their energy from a common source, probably magnetic reconnection in the current sheet behind the erupting structure. In general, the CME peak velocity shows somewhat higher correlations with the non-thermal flare parameters than the CME peak acceleration, except for the spectral index of the accelerated electron spectrum, which yields a higher correlation with the CME peak acceleration (c Almost-Equal-To -0.6), indicating that the hardness of the flare-accelerated electron spectrum is tightly coupled to the impulsive acceleration process of the rising CME structure. We also obtained high correlations between the CME initiation height h{sub 0} and the non-thermal flare parameters, with the highest correlation of h{sub 0} to the spectral index {delta} of flare-accelerated electrons (c Almost-Equal-To 0.8). This means that CMEs erupting at low coronal heights, i.e., in regions of stronger magnetic fields, are accompanied by flares that are more efficient at accelerating electrons to high energies. In the majority of events ({approx}80%), the non-thermal flare emission starts after the CME acceleration, on average delayed by Almost-Equal-To 6 minutes, in line with the standard flare model where the rising flux rope stretches the field lines underneath until magnetic reconnection sets in. We find that the current sheet length at the onset of magnetic reconnection is 21 {+-} 7 Mm. The flare hard X-ray peaks are well synchronized with the peak of the CME acceleration profile, and in 75% of the cases they occur within {+-}5 minutes. Our findings provide strong evidence for the tight coupling between the CME dynamics and the particle acceleration in the associated flare in impulsive events, with the total energy in accelerated electrons being closely correlated with the peak velocity (and thus the kinetic energy) of the CME, whereas the number of electrons accelerated to high energies is decisively related to the CME peak acceleration and the height of the pre-eruptive structure.

Berkebile-Stoiser, S.; Veronig, A. M.; Bein, B. M.; Temmer, M., E-mail: asv@igam.uni-graz.at [Institute of Physics, University of Graz, A-8010 Graz (Austria)

2012-07-01T23:59:59.000Z

127

Surface analysis of rubbers and plastics using secondary neutral mass spectrometry.  

SciTech Connect

Rubber and plastics are complex mixtures of long-chain polymers, smaller organic additives used as plasticizers, mildicides, fungicides, colorants, etc., and inorganic additives such as carbon and silica. Surface analysis of such materials is at once difficult and important. The difficulty lies in the need to identify specific carbon molecules on a very similar organic surface. The importance arises from the dramatic effect that the distribution and concentration of additives have on the physical properties of polymeric materials. Recently we have had some success in applying laser desorption post-ionization mass spectrometry in measuring the surface concentration and distribution of both additives and the polymer molecules themselves. The key has been to use the photoionization properties of the analyte of interest to augment mass spectrometric information.

Pellin, M. J.; Savina, M. R.

1999-08-23T23:59:59.000Z

128

On-line microdialysis sample cleanup for electrospray ionization mass spectrometry of nucleic acid samples  

SciTech Connect

A major limitation of electrospray ionization mass spectrometry (ESI-MS) for oligonucleotide analysis arises due to sodium adduction, a problem that increases with molecular weight. Sodium adduction can preclude useful measurements when limited sample sizes prevent off-line cleanup. A novel and generally useful on-line microdialysis technique is described for the rapid (nearly 1-5 min) DNA sample cleanup for ESI-MS. Mass spectra of oligonucleotides of different size and sequence showing no significant sodium adduct peaks were obtained using the on-line microdialysis system with sodium chloride concentrations as high as 250 mM. Signal-to-noise ratios were also greatly enhanced compared to direct infusion of the original samples. By using ammonium acetate as the dialysis buffer, it was also found that the noncovalent association of double-stranded oligonucleotides could be preserved during the microdialysis process, allowing analysis by ESI-MS. 33 refs., 6 figs.

Liu, C.; Wu, Q.; Harms, A.C.; Smith, R.D. [Pacific Northwest National Lab., Richland, WA (United States)] [Pacific Northwest National Lab., Richland, WA (United States)

1996-09-15T23:59:59.000Z

129

Biases in Ion Transmission Through an Electrospray Ionization-Mass Spectrometry Capillary Inlet  

SciTech Connect

The standard heated capillary inlet of an electrospray ionization mass spectrometry (ESI-MS) interface was compared with shorter versions of the inlet to determine the effects on transmission and ionization efficiencies for low-flow electrosprays. The primary finding of the study was a large bias towards higher mobility species in the electrospray current losses to the inside walls of the inlet. The transmission efficiency increased with decreasing capillary length due to reduced losses along the capillary. A decrease in transmission efficiency was also confirmed for electrosprays of higher conductivity solvents. A direct correlation between mass spectrometry sensitivity and the transmitted electrospray current was not observed as some analytes showed little to no increase in sensitivity while others showed as high as a 15 – fold increase. The variation was shown to at least be partially dependent on the analytes’ mobilities. Higher mobility analytes demonstrated a larger increase in sensitivity when shorter inlets were used. The results indicate that considerable biases against higher mobility species can be produced by the use of long capillary inlets in the ESI-MS interface and strategies are provided to minimize the bias against higher mobility species for efficient ion transmission through the heated capillary interface.

Page, Jason S.; Marginean, Ioan; Baker, Erin Shammel; Kelly, Ryan T.; Tang, Keqi; Smith, Richard D.

2009-12-01T23:59:59.000Z

130

Accelerator Mass Spectrometric (AMS) Measurements of Plutonium Activity Concentrations and 240Pu/239Pu Atom Ratios In Soil Extracts Supplied by the Carlsbad Environmental Monitoring & Research Center  

SciTech Connect

Plutonium-239 ({sup 239}Pu) and plutonium-239+240 ({sup 239+240}Pu) activities concentrations and {sup 240}Pu/{sup 239}Pu atom ratios are reported for a series of chemically purified soil extracts received from the Carlsbad Environmental Monitoring & Research Center (CEMRC) in New Mexico. Samples were analyzed without further purification at the Lawrence Livermore National Laboratory (LLNL) using accelerator mass spectrometry (AMS). This report also includes a brief description of the AMS system and internal laboratory procedures used to ensure the quality and reliability of the measurement data.

Hamilton, T F; Brown, T A; Marchetti, A A; Martinelli, R E; Kehl, S R

2005-02-28T23:59:59.000Z

131

Standard test method for isotopic abundance analysis of uranium hexa?uoride and uranyl nitrate solutions by multi-collector, inductively coupled plasma-mass spectrometry  

E-Print Network (OSTI)

Standard test method for isotopic abundance analysis of uranium hexa?uoride and uranyl nitrate solutions by multi-collector, inductively coupled plasma-mass spectrometry

American Society for Testing and Materials. Philadelphia

2008-01-01T23:59:59.000Z

132

Chemical crosslinking and mass spectrometry studies of the structure and dynamics of membrane proteins and receptors.  

SciTech Connect

Membrane proteins make up a diverse and important subset of proteins for which structural information is limited. In this study, chemical cross-linking and mass spectrometry were used to explore the structure of the G-protein-coupled photoreceptor bovine rhodopsin in the dark-state conformation. All experiments were performed in rod outer segment membranes using amino acid 'handles' in the native protein sequence and thus minimizing perturbations to the native protein structure. Cysteine and lysine residues were covalently cross-linked using commercially available reagents with a range of linker arm lengths. Following chemical digestion of cross-linked protein, cross-linked peptides were identified by accurate mass measurement using liquid chromatography-fourier transform mass spectrometry and an automated data analysis pipeline. Assignments were confirmed and, if necessary, resolved, by tandem MS. The relative reactivity of lysine residues participating in cross-links was evaluated by labeling with NHS-esters. A distinct pattern of cross-link formation within the C-terminal domain, and between loop I and the C-terminal domain, emerged. Theoretical distances based on cross-linking were compared to inter-atomic distances determined from the energy-minimized X-ray crystal structure and Monte Carlo conformational search procedures. In general, the observed cross-links can be explained by re-positioning participating side-chains without significantly altering backbone structure. One exception, between C3 16 and K325, requires backbone motion to bring the reactive atoms into sufficient proximity for cross-linking. Evidence from other studies suggests that residues around K325 for a region of high backbone mobility. These findings show that cross-linking studies can provide insight into the structural dynamics of membrane proteins in their native environment.

Haskins, William E.; Leavell, Michael D.; Lane, Pamela; Jacobsen, Richard B.; Hong, Joohee; Ayson, Marites J.; Wood, Nichole L.; Schoeniger, Joseph S.; Kruppa, Gary Hermann; Sale, Kenneth L.; Young, Malin M.; Novak, Petr

2005-03-01T23:59:59.000Z

133

CURRENT SHEET MASS LEAKAGE IN A PULSED PLASMA ACCELERATOR  

E-Print Network (OSTI)

of the evolution of the sheet and the performance of the device. It was found that after an initial bifurcation phase, the current sheet in this device enters a steady-state phase of propagation during which the mass and Peter Norgaard, thank you for listening to my attempts to explain my research and giving me valuable

Choueiri, Edgar

134

Shotgun Approach for Quantitative Imaging of Phospholipids Using Nanospray Desorption Electrospray Ionization Mass Spectrometry  

SciTech Connect

Mass spectrometry imaging (MSI) has been extensively used for determining spatial distributions of molecules in biological samples, and there is increasing interest in using MSI for quantification. Nanospray desorption electrospray ionization, or nano-DESI, is an ambient MSI technique where a solvent is used for localized extraction of molecules followed by nanoelectrospray ionization. Doping the nano-DESI solvent with carefully selected standards enables online quantification during MSI experiments. In this proof-of-principle study, we demonstrate this quantification approach can be extended to provide shotgun-like quantification of phospholipids in thin brain tissue sections. Specifically, two phosphatidylcholine (PC) standards were added to the nano-DESI solvent for simultaneous imaging and quantification of 22 PC species observed in nano-DESI MSI. Furthermore, by combining the quantitative data obtained in the individual pixels, we demonstrate quantification of these PC species in seven different regions of a rat brain tissue section.

Lanekoff, Ingela T.; Thomas, Mathew; Laskin, Julia

2014-02-04T23:59:59.000Z

135

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

SciTech Connect

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 {micro}g L{sup -1} or better were found for P, Mn, Fe, Cu, and Zn in a 60 {micro}L injection in a physiological saline matrix.

Nathan Joe Saetveit

2008-08-18T23:59:59.000Z

136

Characterization of the microdialysis junction interface for capillary electrophoresis/microelectrospray ionization mass spectrometry  

SciTech Connect

A capillary electrophoresis/electrospray ionization mass spectrometry (CE/ESI-MS) interface, based on an electric circuit across a microdialysis membrane surrounding a short capillary segment closely connected to the separation capillary terminus, is demonstrated to be sensitive, efficient, and rugged. A microspray type ionization emitter produces a stable electrospray at the low flow rates provided by CE and thus avoids both the need for a makeup liquid flow provided by liquid junction or sheath flow interfaces and the subsequent dilution and reduction in sensitivity. Reproducibility studies and comparisons with CE/UV and the CE/sheath flow interface with ESI-MS are presented. Additionally, postrun acidification via the microdialysis junction interface is demonstrated and shown to be capable of denaturing the holomyoglobin protein noncovalent complex while maintaining separation efficiency. 21 refs., 7 figs., 1 tab.

Severs, J.C.; Smith, R.D. [Pacific Northwest National Lab., Richland, WA (United States)] [Pacific Northwest National Lab., Richland, WA (United States)

1997-06-01T23:59:59.000Z

137

Characterization of Coordination Complexes by Desorption Electrospray Mass Spectrometry with a Capillary Target  

SciTech Connect

Metal coordination complexes were formed directly from liquid surfaces using desorption electrospray ionization (DESI) mass spectrometry. The approach is attractive because it separates complexities of ESI spray droplet formation from delivery of the analyte solution, and thereby gets around difficulty resulting from alteration of the spray process by changes in solution chemistry. Cs+, Ba2+, and La3+ coordination complexes were formed using 18-crown-6 (18c6) and triethylphosphate (TEP) as ligands (L), that had the general formula [Mn+(NO3-)n-1(L)m]+. Formation of singly charged cation complexes was preferred, with charge reduction at the metal site accomplished by attachment of nitrate. Using TEP as a model phosphoryl ligand, alkali metals coordinate with up to three ligands, with Cs+ preferring fewer than Na+. Ba2+ and La3+ are formed as ion pair complexes [Ba(NO3)]+ and [La(NO3)2]+, and both will coordinate with up to four TEP ligands. Using 18c6, Cs+ forms a bis-ligand complex. In contrast, [Ba(NO3)]+ prefers a single 18c6 ligand, while La forms mainly [La(NO3)2(18c6)]+, for which DFT calculations suggested a structure in which the nitrate ligands occupy pseudo-axial positions on opposing sides of the crown. Lower abundances of bis-18c6 complexes were also formed together with doubly charged [La(NO3)(18c6)n]2+ complexes (n = 2 – 4). The results suggest an alternative strategy for probing metal speciation in solution that is less perturbed by the droplet formation and ionization mechanisms operating in conventional electrospray ionization mass spectrometry.

Gary S. Groenewold; Anthony D. Appelhans; Michael E. McIlwain; Garold L. Gresham

2011-03-01T23:59:59.000Z

138

MAINTAINING HIGH RESOLUTION MASS SPECTROMETRY CAPABILITIES FOR NATIONAL NUCLEAR SECURITY ADMINISTRATION APPLICATIONS  

SciTech Connect

The Department of Energy (DOE) National Nuclear Security Administration (NNSA) has a specialized need for analyzing low mass gas species at very high resolutions. The currently preferred analytical method is electromagnetic sector mass spectrometry. This method allows the NNSA Nuclear Security Enterprise (NSE) to resolve species of similar masses down to acceptable minimum detection limits (MDLs). Some examples of these similar masses are helium-4/deuterium and carbon monoxide/nitrogen. Through the 1980s and 1990s, there were two vendors who supplied and supported these instruments. However, with declining procurements and down turns in the economy, the supply of instruments, service and spare parts from these vendors has become less available, and in some cases, nonexistent. The largest NSE user of this capability is the Savannah River Site (SRS), located near Aiken, South Carolina. The Research and Development Engineering (R&DE) Group in the Savannah River National Laboratory (SRNL) investigated the areas of instrument support that were needed to extend the life cycle of these aging instruments. Their conclusions, as to the focus areas of electromagnetic sector mass spectrometers to address, in order of priority, were electronics, software and hardware. Over the past 3-5 years, the R&DE Group has designed state of the art electronics and software that will allow high resolution legacy mass spectrometers, critical to the NNSA mission, to be operated for the foreseeable future. The funding support for this effort has been from several sources, including the SRS Defense Programs, NNSA Readiness Campaign, Pantex Plant and Sandia National Laboratory. To date, electronics systems have been upgraded on one development system at SRNL, two production systems at Pantex and one production system at Sandia National Laboratory. An NSE working group meets periodically to review strategies going forward. The R&DE Group has also applied their work to the electronics for a Thermal Ionization Mass Spectrometer (TIMS) instrument, which applies a similar mass spectrometric technology for resolving high mass isotopes, such as plutonium and uranium. Due to non-compete clauses for DOE, all work has been performed and applied to instruments which are obsolete and are no longer supported by the original vendor.

Wyrick, S.; Cordaro, J.; Reeves, G.; Mcintosh, J.; Mauldin, C.; Tietze, K.; Varble, D.

2011-06-06T23:59:59.000Z

139

Proceedings of the relevance of mass spectrometry to DNA sequence determination: Research needs for the Human Genome Program  

SciTech Connect

A workshop was sponsored for the US Department of Energy (DOE), Office of Health and Environmental Research by Pacific Northwest Laboratory, April 4--5, 1990, in Seattle, Washington, to examine the potential role of mass spectrometry in the joint DOE/National Institutes of Health (NIH) Human Genome Program. The workshop was occasioned by recent developments in mass spectrometry that are providing new levels for selectivity, sensitivity, and, in particular, new methods of ionization appropriate for large biopolymers such as DNA. During discussions, three general mass spectrometric approaches to the determination of DNA sequence were considered: (1) the mass spectrometric detection of isotopic labels from DNA sequencing mixtures separated using gel electrophoresis, (2) the direct mass spectrometric analysis from direct ionization of unfractionated sequencing mixtures where the measured mass of the constituents functions to identify and order the base sequence (replacing separation by gel electrophoresis), and (3) an approach in which a single highly charged molecular ion of a large DNA segment produced is rapidly sequenced in an ion cyclotron resonance ion trap. The consensus of the workshop was that, on the basis of the new developments, mass spectrometry has the potential to provide the substantial increases in sequencing speed required for the Human Genome Program. 66 refs., 3 tabs.

Edmonds, C.G.; Smith, R.D. (Pacific Northwest Lab., Richland, WA (USA)); Smith, L.M. (Wisconsin Univ., Madison, WI (USA))

1990-11-01T23:59:59.000Z

140

Response of single cells and cell extracts to irradiation as detected by time-of-flight secondary ion mass spectrometry (ToF-SIMS)  

Science Journals Connector (OSTI)

...secondary ion mass spectrometry (ToF-SIMS) Mark G. Knize Kuang Jen Wu David L...Secondary Ion Mass Spectrometry (ToF-SIMS) uses an ion beam to desorb and ionize...Together these experiments show that ToF-SIMS analysis of single cells can be used to...

Mark G. Knize; Kuang Jen Wu; David L. Shattuck; Ligang Wu; Erik J. Nelson; Jennifer L. Montgomery; Cynthia B. Thomas; James S. Felton; Kristen S. Kulp

2005-05-01T23:59:59.000Z

Note: This page contains sample records for the topic "accelerator mass spectrometry" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

Quantitation by Gas Chromatography-Chemical Ionization-Mass Spectrometry of Phenylalanine Mustard in Plasma of Patients  

Science Journals Connector (OSTI)

...1980 research-article Quantification by Gas Chromatography of N,N-Di-(2-chloroethyl...addressed. A sensitive method, based on gas chromatography using a phosphorus-specific...derivatization process has been elucidated using gas chromatography-electron impact mass spectrometry...

Sharon L. Pallante; Catherine Fenselau; Robert G. Mennel; Robert B. Brundrett; Mark Appler; Neil B. Rosenshein; Michael Colvin

1980-07-01T23:59:59.000Z

142

A Dual Platform for Selective Analyte Enrichment and Ionization in Mass Spectrometry Using Aptamer-Conjugated Graphene Oxide  

E-Print Network (OSTI)

A Dual Platform for Selective Analyte Enrichment and Ionization in Mass Spectrometry Using Aptamer/Biosensing and Chemometrics, College of Biology, College of Chemistry and Chemical Engineering, Hunan UniVersity, Changsha and detection platform for analytes from complex biological media. We have shown that cocaine and adenosine can

Tan, Weihong

143

Imaging and 3D Elemental Characterization of Intact Bacterial Spores by High-Resolution Secondary Ion Mass Spectrometry  

Science Journals Connector (OSTI)

We present a quantitative, imaging technique based on nanometer-scale secondary ion mass spectrometry for mapping the 3D elemental distribution present in an individual micrometer-sized Bacillus spore. We use depth profile analysis to access the 3D ...

Sutapa Ghosal; Stewart J. Fallon; Terrance J. Leighton; Katherine E. Wheeler; Michael J. Kristo; Ian D. Hutcheon; Peter K. Weber

2008-06-26T23:59:59.000Z

144

Application of coincidence ion mass spectrometry for chemical and structural analysis at the sub-micron scale  

E-Print Network (OSTI)

Surfaces can be probed with a variant of secondary ion mass spectrometry (SIMS) where the bombardment is with a sequence of single keV projectiles, each resolved in time and space, coupled with the separate record of the secondary ions (SIs) ejected...

Balderas, Sara

2005-11-01T23:59:59.000Z

145

Hydrogen-exchange mass spectrometry for the study of intrinsic disorder in proteins Deepa Balasubramaniam, Elizabeth A. Komives  

E-Print Network (OSTI)

Review Hydrogen-exchange mass spectrometry for the study of intrinsic disorder in proteins Deepa 2012 Keywords: Amide exchange Intrinsically disordered proteins Flow quench Amyloid Coupled folding) is seeing wider use for the identification of intrinsically disordered parts of proteins. In this review, we

Komives, Elizabeth A.

146

Method Validation for the Simultaneous Determination of Fecal Sterols in Surface Waters by Gas Chromatography-Mass Spectrometry  

Science Journals Connector (OSTI)

......waters is estimated by gas chromatographic (GC...steroids and endogenous CHL production and metabolism, the sterol...Sterols in Surface Waters by Gas ChromatographyMass Spectrometry...ally quantitated by gas chromatography (GC...characterized. Because cost and time effectiveness......

Sándor Szucs; Attila Sárváry; Terry Cain; Róza Ádány

2006-02-01T23:59:59.000Z

147

Assessment of Non-traditional Isotopic Ratios by Mass Spectrometry for Analysis of Nuclear Activities: Annual Report Year 2  

SciTech Connect

The objective of this work is to identify isotopic ratios suitable for analysis via mass spectrometry that distinguish between commercial nuclear reactor fuel cycles, fuel cycles for weapons grade plutonium, and products from nuclear weapons explosions. Methods will also be determined to distinguish the above from medical and industrial radionuclide sources. Mass spectrometry systems will be identified that are suitable for field measurement of such isotopes in an expedient manner. Significant progress has been made with this project within the past year: (1) Isotope production from commercial nuclear fuel cycles and nuclear weapons fuel cycles have been modeled with the ORIGEN and MCNPX codes. (2) MCNPX has been utilized to calculate isotopic inventories produced in a short burst fast bare sphere reactor (to approximate the signature of a nuclear weapon). (3) Isotopic ratios have been identified that are good for distinguishing between commercial and military fuel cycles as well as between nuclear weapons and commercial nuclear fuel cycles. (4) Mass spectrometry systems have been assessed for analysis of the fission products of interest. (5) A short-list of forensic ratios have been identified that are well suited for use in portable mass spectrometry systems.

Biegalski, S; Buchholz, B

2009-08-26T23:59:59.000Z

148

The origin of mass and the experiments on future high energy accelerators  

E-Print Network (OSTI)

The visible universe - it is the universe of nucleons and electrons. The appearance of nucleon mass is caused by the violation of chiral symmetry in quantum chromodynamics (QCD). For this reason, the experiments on high energy accelerators cannot shed light on the origin of the matter in the visible universe. The origin of the mass of matter will be clarified, when the mechanism of chiral symmetry violation in QCD will be elucidated.

B. L. Ioffe

2006-01-30T23:59:59.000Z

149

Dosimetry and spectrometry at accelerator based neutron source for boron neutron capture therapy  

Science Journals Connector (OSTI)

An innovative accelerator-based neutron source for boron neutron capture therapy has started operation at the Budker Institute of Nuclear Physics, Novosibirsk. This facility is based on a compact vacuum insulation tandem accelerator designed to produce proton current up to 10 mA. Epithermal neutrons are proposed to be generated by 1.915 MeV protons bombarding a lithium target using 7Li(p,n)7Be threshold reaction. In the article, techniques to detect neutron and gamma-rays at the facility are described. Gamma radiation is measured with NaI and BGO gamma-spectrometers. The total yield of neutrons is determined by measuring the 477 keV ?-quanta from beryllium decay. For the rough analysis of the generated neutron spectrum we used bubble detectors. As the epithermal neutrons are of interest for neutron capture therapy the NaI detector is used as activation detector. We plan to use a time-of-flight technique for neutron spectra measurement. To realize this technique a new solution of short time neutron generation is proposed.

B. Bayanov; A. Burdakov; A. Kuznetsov; A. Makarov; S. Sinitskii; Yu. Sulyaev; S. Taskaev

2010-01-01T23:59:59.000Z

150

Improving boron isotope ratio measurement precision with quadrupole inductively coupled plasma-mass spectrometry  

Science Journals Connector (OSTI)

A method was developed to improve the precision of inductively coupled plasma quadrupole mass spectrometry (ICP-QMS) for the determination of boron isotope ratios (11B/10B) in various environmental materials including seawater. This approach is based on the common analyte internal standardization (CAIS) chemometric algorithm. The sample solution obtained after digestion is spiked with lithium, and both 7Li/6Li and 11B/10B values are measured using long-counting periods (20 min). The CAIS algorithm corrects the measured 11B/10B values for (a) statistical fluctuations resulting from short-term noise; (b) drift in 11B-to-10B ratio as a result of long-term deviation in instrumental parameters likely to occur during long counting times; (c) change in 11B-to-10B ratio caused by variation in matrix elements concentrations; and (d) drift in mass bias correction factor. Comparing boron isotopic ratios in seawater measured by conventional and the new isotope ratio methods validates the procedure. A synthetic isotopic mixture of boron SRM 951 and enriched 10B SRM 952 also was examined. The CAIS method provided a measured boron isotopic ratio precision of 0.05% R.S.D. while eliminating 5.1% matrix concentration error and 0.25% instrumental drift error.

Assad Al-Ammar; Eva Reitznerová; Ramon M. Barnes

2000-01-01T23:59:59.000Z

151

Size Characterization of Colloidal Platinum Nanoparticles by MALDI-TOF Mass Spectrometry  

SciTech Connect

In this work, matrix assisted laser desorption ionization-time-of-flight (MALDI-TOF) mass spectrometry (MS) has been utilized to characterize colloidal platinum nanoparticles synthesized in the 1-4 nm size range. The nanoparticles were prepared via a solution-based method in which the size could be controlled by varying reaction conditions, such as the alcohol used as the reductant. Poly(vinylpyrrolidone), or PVP, (MW = 29,000 g/mol) was employed as a capping agent to stabilize the synthesized nanoparticles in solution. A model for determining the size of the metallic nanoparticle core from MALDI-TOF mass spectra has been developed and verified through correlation with particle sizes from transmission electron microscopy (TEM) and X-ray diffraction (XRD) measurements. In this model it was assumed that 1.85 nm nanoparticles are capped by one PVP chain, which was verified through experiments performed with capped and uncapped nanoparticles. Larger nanoparticles are capped by either two (2.60 and 2.94 nm) or three (3.69 nm) PVP chains. These findings clearly indicate the usefulness of MALDI-TOF MS as a technique for fully characterizing nanoscale materials in order to elucidate structure-property relationships.

Navin, Jason K.; Grass, Michael E.; Somorjai, Gabor A.; Marsh, Anderson L.

2009-08-15T23:59:59.000Z

152

Observation of a noncovalent ribonuclease S-protein/S-peptide complex by electrospray ionization mass spectrometry  

SciTech Connect

Electrospray ionization mass spectrometry (ESI-MS) investigations of noncovalently-bound complexes are of great interest because of their relevance to solution biochemistry. ESI-MS is particularly well suited to studies of weak interactions because it is very gentle and it allows studies to be performed under physiological or near-physiological solution conditions. However, it is not yet fully understood which weakly-bound complexes known to exist in solution will be observable by ESI-MS, or what minimum binding strength may be required for ESI-MS observation. Also unclear is whether complexes observed by ESI-MS reflect only species present in the bulk solution, or whether complexes also reflect aggregation in electrospray-generated microdroplets. We address some of these issues by employing ribonuclease S (RNase-S) as a test of the applicability of ESI-MS for analysis of noncovalent complexes. These results show that the ESI mass spectra of R Nase-S can reflect the specificity of binding in solution. 33 refs., 2 figs.

Loo, R.R.O.; Goodlett, D.R.; Smith, R.D.; Loo, J.A. (Pacific Northwest Lab., Richland, WA (United States))

1993-05-19T23:59:59.000Z

153

Control of Analyte Electrolysis in Electrospray Ionization Mass Spectrometry Using Repetitively Pulsed High Voltage  

SciTech Connect

Analyte electrolysis using a repetitively pulsed high voltage ion source was investigated and compared to that using a regular, continuously operating direct current high voltage ion source in electrospray ionization mass spectrometry. The extent of analyte electrolysis was explored as a function of the length and frequency of the high voltage pulse using the model compound reserpine in positive ion mode. Using +5 kV as the maximum high voltage amplitude, reserpine was oxidized to its 2, 4, 6 and 8-electron oxidation products when direct current high voltage was employed. In contrast, when using a pulsed high voltage, oxidation of reserpine was eliminated by employing the appropriate high voltage pulse length and frequency. This effect was caused by inefficient mass transport of the analyte to the electrode surface during the duration of the high voltage pulse and the subsequent relaxation of the emitter electrode/ electrolyte interface during the time period when the high voltage was turned off. This mode of ESI source operation allows for analyte electrolysis to be quickly and simply switched on or off electronically via a change in voltage pulse variables.

Kertesz, Vilmos [ORNL; Van Berkel, Gary J [ORNL

2011-01-01T23:59:59.000Z

154

Ionization and transmission efficiency in an electrospray ionization-mass spectrometry interface  

SciTech Connect

The efficiency of sample ionization by electrospray ionization (ESI) and the transmission of the charged droplets and gas-phase ions through an ESI interface were investigated in order to advance the understanding of how these factors affect mass spectrometry (MS) sensitivity. In addition, the effects of the ES emitter distance to the inlet, solution flow rate, and inlet temperature to the ionization and transmission efficiency were characterized. Quantitative measurements of ES current loss throughout the ESI interface were accomplished by electrically isolating the front surface of the interface from the inner wall of the heated inlet capillary, enabling losses on the two surfaces to be distinguished. The ES current lost to the front surface of the ESI interface was also spatially profiled with a linear array of 340-µm-dia. electrodes placed adjacent to the inlet capillary entrance. Current transmitted as gas-phase ions was differentiated from charged droplets and solvent clusters by directly measuring sensitivity with a single quadrupole mass spectrometer. The study has revealed a large sampling efficiency into the inlet capillary (>90% at an emitter distance of 1 mm), a global rather than a local gas dynamic effect on the shape of the ES plume due to the gas flow conductance limit of the inlet capillary, a large (>80%) loss of analyte after transmission through the inlet due to incomplete desolvation at a solution flow rate of 1.0 µL/min, and a decrease in analyte peak intensity at lower temperatures, despite a large increase in ES current transmission efficiency. These studies provide a clearer understanding of the parameters affecting ion transmission into the mass spectrometer, and will serve to guide the design of more efficient instrument interfaces.

Page, Jason S.; Kelly, Ryan T.; Tang, Keqi; Smith, Richard D.

2007-09-01T23:59:59.000Z

155

ACCELERATION OF CORONAL MASS EJECTIONS FROM THREE-DIMENSIONAL RECONSTRUCTION OF STEREO IMAGES  

SciTech Connect

We employ a three-dimensional (3D) reconstruction technique for the first time to study the kinematics of six coronal mass ejections (CMEs), using images obtained from the COR1 and COR2 coronagraphs on board the twin STEREO spacecraft, and also the eruptive prominences (EPs) associated with three of them using images from the Extreme UltraViolet Imager. A feature in the EPs and leading edges (LEs) of all the CMEs was identified and tracked in images from the two spacecraft, and a stereoscopic reconstruction technique was used to determine the 3D coordinates of these features. True velocity and acceleration were determined from the temporal evolution of the true height of the CME features. Our study of the kinematics of the CMEs in 3D reveals that the CME LE undergoes maximum acceleration typically below 2 R{sub sun}. The acceleration profiles of CMEs associated with flares and prominences exhibit different behaviors. While the CMEs not associated with prominences show a bimodal acceleration profile, those associated with prominences do not. Two of the three associated prominences in the study show a high and increasing value of acceleration up to a distance of almost 4 R{sub sun}, but acceleration of the corresponding CME LE does not show the same behavior, suggesting that the two may not be always driven by the same mechanism. One of the CMEs, although associated with a C-class flare, showed unusually high acceleration of over 1500 m s{sup -2}. Our results therefore suggest that only the flare-associated CMEs undergo residual acceleration, which indicates that the flux injection theoretical model holds well for the flare-associated CMEs, but a different mechanism should be considered for EP-associated CMEs.

Joshi, Anand D.; Srivastava, Nandita, E-mail: janandd@prl.res.in [Udaipur Solar Observatory, Physical Research Laboratory, P.O. Box 198, Badi Road, Udaipur 313001 (India)

2011-09-20T23:59:59.000Z

156

Simultaneous Quantitation of 2-Acetyl-4-tetrahydroxybutylimidazole, 2- and 4-Methylimidazoles, and 5-Hydroxymethylfurfural in Beverages by Ultrahigh-Performance Liquid Chromatography–Tandem Mass Spectrometry  

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Simultaneous Quantitation of 2-Acetyl-4-tetrahydroxybutylimidazole, 2- and 4-Methylimidazoles, and 5-Hydroxymethylfurfural in Beverages by Ultrahigh-Performance Liquid Chromatography–Tandem Mass Spectrometry ... An ultrahigh-performance liquid chromatography (UHPLC) tandem mass spectrometric (MS/MS) method was developed for the simultaneous quantification of 2-acetyl-4-tetrahydroxybutylimidazole (THI), 2- and 4-methylimidazoles (2-MI and 4-MI), and 5-hydroxymethylfurfural (HMF) in beverage samples. ... 2-acetyl-4-tetrahydroxybutylimidazole; methylimidazole; 5-hydroxymethylfurfural; carcinogen; beverage; UHPLC; mass spectrometry ...

Jinyuan Wang; William C. Schnute

2011-12-30T23:59:59.000Z

157

Using Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS) for sensitive cell type differentiation and analysis of paraffin- embedded bladder and prostate tissue sections: Applications for cancer prognosis  

Science Journals Connector (OSTI)

...Secondary Ion Mass Spectrometry (ToF-SIMS) for sensitive cell type differentiation...Secondary Ion Mass Spectrometry (ToF-SIMS), a powerful imaging mass spectrometry...molecular images of the tissues. ToF-SIMS measurements utilize a finely focused primary...

Kristen Kulp; Elena Berman; Susan Fortson; Kuang Jen Wu; Mark Knize; Ligang Wu; Ralph deVere White; Regina Gandour-Edwards; David Seligson; Lee Goodglick; David Chia; Shelia Tze; James Felton

2007-05-01T23:59:59.000Z

158

Detection of Biosignatures by Geomatrix-Assisted Laser Desorption/Ionization (GALDI) Mass Spectrometry  

SciTech Connect

Identification of mineral-associated biosignatures is of significance for retrieving biochemical information from geological records here on Earth and detecting signs of life on other planets, such as Mars. The importance of the geomatrix for identifying amino acids (e.g., histidine, threonine, and cysteine) and small proteins (e.g., gramicidin S) was investigated by laser desorption Fourier transform mass spectrometry. The investigated geomatrices include analogues of Fe-bearing minerals such as hematite and Na-bearing evaporites (e.g., halite). Samples were prepared by two methods: 1) application of analyte to the geomatrix surface and 2) production of homogenous analyte:geomatrix mixtures. Comparison of the two sample preparation methods revealed that the mixing method produces a better signal/noise ratio than surface application for the analyses of amino acids. The composition of the geomatrix has a profound influence on the detection of biomolecules. Peaks corresponding to the cation-attached biomolecular ions were observed for the Na-bearing evaporite analogue. No detectable peaks for the biomolecular ion species were observed when the biomolecules were associated with Fe-bearing minerals. Instead, only minor peaks were observed that may correspond to ions from fragments of the biomolecules. Depending on the underlying mineral composition, geomatrix-assisted laser desorption/ionization shows promise for directly identifying biosignatures associated with minerals.

Jill R. Scott; Beizhan Yan; Daphne L. Stoner; J. Michelle Kotler; Nancy W. Hinman

2007-04-01T23:59:59.000Z

159

Observation of the noncovalent quaternary associations of proteins by electrospray ionization mass spectrometry  

SciTech Connect

The noncovalent tetrameric active forms of avidin, concanavalin A (Con A), and adult human hemoglobin (HbA[sub 0]) can be observed intact in the gas phase by electrospray ionization mass spectrometry (ESI-MS). The atmosphere-vacuum ESI interface conditions strongly influence the retention of these weak noncovalent solution associations into the gas phase, as well as the average extent of charging for the subunits upon dissociation. The known solution pH dependence of the dimer-tetramer equilibrium of Con A was observed by ESI-MS, and the intact heterodimeric and -tetrameric active forms of adult human HbA[sub 0], ([alpha][beta]) and ([alpha][beta])[sub 2], with the prosthetic heme groups could also be characterized by ESI-MS. Under harsher interface conditions a species corresponding to a trimer was observed for each of the proteins, a species not known to be formed under physiological conditions. Differences in the relative stabilities of these tetrameric proteins, formed from the known solution structures, are also qualitatively consistent with the gas-phase stability observed with ESI-MS by adjusting the atmosphere-vacuum interface conditions. The hemoglobin tetramer was found to be less stable in the gas phase than either the Con A or avidin tetramer, consistent with solution dissociation constants. 21 refs., 14 figs.

Light-Wahl, K.J.; Schwartz, B.L.; Smith, R.D. (Pacific Northwest Lab., Richland, WA (United States))

1994-06-15T23:59:59.000Z

160

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

SciTech Connect

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.

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

1994-06-01T23:59:59.000Z

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161

Shape Changing and Accelerating Solitons in the Integrable Variable Mass Sine-Gordon Model  

SciTech Connect

The sine-Gordon model with a variable mass (VMSG) appears in many physical systems, ranging from the current through a nonuniform Josephson junction to DNA-promoter dynamics. Such models are usually nonintegrable with solutions found numerically or perturbatively. We construct a class of VMSG models, integrable at both the classical and the quantum levels with exact soliton solutions, which can accelerate and change their shape, width, and amplitude simulating realistic inhomogeneous systems at certain limits.

Kundu, Anjan [Theory Group, Saha Institute of Nuclear Physics, Calcutta (India)

2007-10-12T23:59:59.000Z

162

Detection of Chemical Weapon Agents and Simulants Using Chemical Ionization Reaction Time-of-Flight Mass Spectrometry  

Science Journals Connector (OSTI)

Detection of Chemical Weapon Agents and Simulants Using Chemical Ionization Reaction Time-of-Flight Mass Spectrometry ... Chemical weapons were first used on a large scale in warfare in World War 1, where chlorine and sulfur mustard were used extensively. ... Many analytical methods have been developed for the detection of the active chemical constituents of chemical weapons, chemical weapon agents (CWAs), and their breakdown products in soil,5-9 groundwater,10,11 and air. ...

Rebecca L. Cordell; Kerry A. Willis; Kevin P. Wyche; Robert S. Blake; Andrew M. Ellis; Paul S. Monks

2007-09-26T23:59:59.000Z

163

Development of mass spectrometry by high energy focused heavy ion beam: MeV SIMS with 8 MeV Cl7+ beam  

Science Journals Connector (OSTI)

Abstract Particle induced X-ray emission (PIXE) at microprobe of Jožef Stefan Institute is used to measure two-dimensional quantitative elemental maps of biological tissue. To improve chemical and biological understanding of the processes in vivo, supplementary information about chemical bonding and/or molecular distributions could be obtained by heavy-ion induced molecular desorption and a corresponding mass spectroscopy with Time-Of-Flight (TOF) mass spectrometer. As the method combines the use of heavy focused ions in MeV energy range and TOF Secondary Ion Mass Spectrometry, it is denoted as MeV SIMS. At Jožef Stefan Institute, we constructed a linear TOF spectrometer and mount it to our multipurpose nuclear microprobe. A beam of 8 MeV 35Cl7+ could be focused to a diameter of better than 3 ?m × 3 ?m and pulsed by electrostatic deflection at the high-energy side of accelerator. TOF mass spectrometer incorporates an 1 m long drift tube and a double stack microchannel plate (MCP) as a stop detector positioned at the end of the drift path. Secondary ions are focused at MCP using electrostatic cylindrical einzel lens. Time of flight spectra are currently acquired with a single-hit time-to-digital converter. Pulsed ion beam produces a shower of secondary ions that are ejected from positively biased target and accelerated towards MCP. We start our time measurement simultaneously with the start of the beam pulse. Signal of the first ion hitting MCP is used to stop the time measurement. Standard pulses proportional to the time of flight are produced with time to analog converter (TAC) and fed into analog-to-digital converter to obtain a time histogram. To enable efficient detection of desorbed fragments with higher molecular masses, which are of particular interest, we recently implemented a state-of art Field Programmable Gate Array (FPGA)-based multi-hit TOF acquisition. To test the system we used focused 8 MeV 35Cl7+ ion beam with pulse length of 180 ns. Mass resolution of measured SIMS spectra, dominantly determined by the duration of the beam pulse, is in good agreement with resolution estimated from pulse length. With improved high-voltage switching ability that will enable beam pulses with duration of 50 ns, a mass resolution of better than 500 is anticipated.

Luka Jeromel; Zdravko Siketi?; Nina Ogrinc Poto?nik; Primož Vavpeti?; Zdravko Rupnik; Klemen Bu?ar; Primož Pelicon

2014-01-01T23:59:59.000Z

164

A new detector for mass spectrometry: Direct detection of low energy ions using a multi-pixel photon counter  

SciTech Connect

A new type of ion detector for mass spectrometry and general detection of low energy ions is presented. The detector consists of a scintillator optically coupled to a single-photon avalanche photodiode (SPAD) array. A prototype sensor has been constructed from a LYSO (Lu{sub 1.8}Y{sub 0.2}SiO{sub 5}(Ce)) scintillator crystal coupled to a commercial SPAD array detector. As proof of concept, the detector is used to record the time-of-flight mass spectra of butanone and carbon disulphide, and the dependence of detection sensitivity on the ion kinetic energy is characterised.

Wilman, Edward S.; Gardiner, Sara H.; Vallance, Claire [Department of Chemistry, University of Oxford, Chemistry Research Laboratory, 12 Mansfield Rd, Oxford OX1 3TA (United Kingdom); Nomerotski, Andrei [Department of Physics, University of Oxford, Denys Wilkinson Building, Keble Rd, Oxford OX1 3RH (United Kingdom); Turchetta, Renato [Rutherford Appleton Laboratory, Chilton, Didcot, Oxfordshire OX11 0QX (United Kingdom); Brouard, Mark [Department of Chemistry, University of Oxford, Physical and Theoretical Chemistry Laboratory, South Parks Rd, Oxford OX1 3QZ (United Kingdom)

2012-01-15T23:59:59.000Z

165

Measurement of low radioactivity background in a high voltage cable by high resolution inductively coupled plasma mass spectrometry  

SciTech Connect

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.

Vacri, M. L. di; Nisi, S.; Balata, M. [Gran Sasso National Laboratory, Chemistry Service, SS 17bis km 18.910, 67100 Assergi (Aq) (Italy)] [Gran Sasso National Laboratory, Chemistry Service, SS 17bis km 18.910, 67100 Assergi (Aq) (Italy)

2013-08-08T23:59:59.000Z

166

Fully Automated Laser Ablation Liquid Capture Sample Analysis using NanoElectrospray Ionization Mass Spectrometry  

SciTech Connect

RATIONALE: Laser ablation provides for the possibility of sampling a large variety of surfaces with high spatial resolution. This type of sampling when employed in conjunction with liquid capture followed by nanoelectrospray ionization provides the opportunity for sensitive and prolonged interrogation of samples by mass spectrometry as well as the ability to analyze surfaces not amenable to direct liquid extraction. METHODS: A fully automated, reflection geometry, laser ablation liquid capture spot sampling system was achieved by incorporating appropriate laser fiber optics and a focusing lens into a commercially available, liquid extraction surface analysis (LESA ) ready Advion TriVersa NanoMate system. RESULTS: Under optimized conditions about 10% of laser ablated material could be captured in a droplet positioned vertically over the ablation region using the NanoMate robot controlled pipette. The sampling spot size area with this laser ablation liquid capture surface analysis (LA/LCSA) mode of operation (typically about 120 m x 160 m) was approximately 50 times smaller than that achievable by direct liquid extraction using LESA (ca. 1 mm diameter liquid extraction spot). The set-up was successfully applied for the analysis of ink on glass and paper as well as the endogenous components in Alstroemeria Yellow King flower petals. In a second mode of operation with a comparable sampling spot size, termed laser ablation/LESA , the laser system was used to drill through, penetrate, or otherwise expose material beneath a solvent resistant surface. Once drilled, LESA was effective in sampling soluble material exposed at that location on the surface. CONCLUSIONS: Incorporating the capability for different laser ablation liquid capture spot sampling modes of operation into a LESA ready Advion TriVersa NanoMate enhanced the spot sampling spatial resolution of this device and broadened the surface types amenable to analysis to include absorbent and solvent resistant materials.

Lorenz, Matthias [ORNL] [ORNL; Ovchinnikova, Olga S [ORNL] [ORNL; Van Berkel, Gary J [ORNL] [ORNL

2014-01-01T23:59:59.000Z

167

Copyright0 1988by San FranciscoPress,Inc., BOX6800, San Franc&o, CA 94101&fM, USA Laser Microprobe Mass Spectrometry  

E-Print Network (OSTI)

Copyright0 1988by San FranciscoPress,Inc., BOX6800, San Franc&o, CA 94101&fM, USA 10 Laser. Bennett, W. Lauwers, A. Vertes, and R. Gijbels Laser microprobe mass spectrometry (LMMS)em- ploys

Vertes, Akos

168

Laser postionization secondary neutral mass spectrometry in tissue: a powerful tool for elemental and molecular imaging in the development of targeted drugs  

Science Journals Connector (OSTI)

...32 Chandra S, Lorey DRI, Smith DR. Quantitative subcellular secondary ion mass spectrometry (SIMS) imaging of boron-10 and boron-11 isotopes in the same cell delivered by two combined BNCT drugs: in vitro studies on human glioblastoma...

Andrea Wittig; Heinrich F. Arlinghaus; Christian Kriegeskotte; Raymond L. Moss; Klaas Appelman; Kurt W. Schmid; Wolfgang A.G. Sauerwein

2008-07-01T23:59:59.000Z

169

Determination of Depleted Uranium in Urine via Isotope Ratio Measurements Using Large-Bore Direct Injection High Efficiency Nebulizer–Inductively Coupled Plasma Mass Spectrometry  

Science Journals Connector (OSTI)

Inductively coupled plasma mass spectrometry (ICP-MS), coupled with a large-bore direct injection high efficiency nebulizer (LB-DIHEN), was utilized to determine the concentration and...

Westphal, Craig S; McLean, John A; Hakspiel, Shelly J; Jackson, William E; McClain, David E; Montaser, Akbar

2004-01-01T23:59:59.000Z

170

Matrix-Assisted Laser Desorption Ionization–Time of Flight Mass Spectrometry: a Fundamental Shift in the Routine Practice of Clinical Microbiology  

Science Journals Connector (OSTI)

...Desorption Ionization-Time of Flight Mass Spectrometry: a Fundamental Shift in the Routine Practice of Clinical Microbiology Andrew...ability to absorb specific laser wavelengths, resulting in electronic excitation of the matrix. A list of matrices commonly used...

Andrew E. Clark; Erin J. Kaleta; Amit Arora; Donna M. Wolk

2013-07-01T23:59:59.000Z

171

Analysis of liquified coal for nitrogenous bases; separation by high performance liquid chromatography and identification by probe microdistillation/mass spectrometry  

E-Print Network (OSTI)

ANALYSIS OF LIQUIFIED COAL FOR NITROGENOUS BASES; SEPARATION BY HIGH PERFORMANCE LIQUID CHROMATOGRAPHY AND IDENTIFICATION BY PROBE MICRODISTILLATION/MASS SPECTROMETRY A Thesis by LEONARD ROYCE SCHRONK Submitted to the Graduate College... AND IDENTIFICATION BY PROBE MICRODISTILLATION/MASS SPECTROMETRY A Thesis by LEONARD ROYCE SCHRONK Approved as to style and content by: Co-Charrman o Commlxtte ) (Co-Chazrman o Committee Me er Hea of Department December 1978 ABSTRACT Analysis of Liquified...

Schronk, Leonard Royce

1978-01-01T23:59:59.000Z

172

Development of A Cryogenic Drift Cell Spectrometer and Methods for Improving the Analytical Figures of Merit for Ion Mobility-Mass Spectrometry Analysis  

E-Print Network (OSTI)

A cryogenic (325-80 K) ion mobility-mass spectrometer was designed and constructed in order to improve the analytical figures-of-merit for the chemical analysis of small mass analytes using ion mobility-mass spectrometry. The instrument incorporates...

May, Jody C.

2010-10-12T23:59:59.000Z

173

Intra-ring variability of Cr, As, Cd, and Pb in red oak revealed by secondary ion mass spectrometry: Implications for environmental biomonitoring  

Science Journals Connector (OSTI)

...21). Mass balance studies suggest...000 tons of Cr wastewater into the watershed during...AMU, atomic mass units. (b...two alternative treatments are considered...J ( 1993 ) in Plants as Biomonitors...Activation Analysis Plants chemistry growth...Spectrometry, Mass, Secondary...

D. J. Brabander; N. Keon; R. H. R. Stanley; H. F. Hemond

1999-01-01T23:59:59.000Z

174

DETERMINATION OF 237NP AND PU ISOTOPES IN LARGE SOIL SAMPLES BY INDUCTIVELY COUPLED PLASMA MASS SPECTROMETRY  

SciTech Connect

A new method for the determination of {sup 237}Np and Pu isotopes in large soil samples has been developed that provides enhanced uranium removal to facilitate assay by inductively coupled plasma mass spectrometry (ICP-MS). This method allows rapid preconcentration and separation of plutonium and neptunium in large soil samples for the measurement of {sup 237}Np and Pu isotopes by ICP-MS. {sup 238}U can interfere with {sup 239}Pu measurement by ICP-MS as {sup 238}UH{sup +} mass overlap and {sup 237}Np via {sup 238}U peak tailing. The method provides enhanced removal of uranium by separating Pu and Np initially on TEVA Resin, then transferring Pu to DGA resin for additional purification. The decontamination factor for removal of uranium from plutonium for this method is greater than 1 x 10{sup 6}. Alpha spectrometry can also be applied so that the shorter-lived {sup 238}Pu isotope can be measured successfully. {sup 239}Pu, {sup 242}Pu and {sup 237}Np were measured by ICP-MS, while {sup 236}Pu and {sup 238}Pu were measured by alpha spectrometry.

Maxwell, S.

2010-07-26T23:59:59.000Z

175

THE INFLUENCE OF THE MASS RATIO ON THE ACCELERATION OF PARTICLES BY FILAMENTATION INSTABILITIES  

SciTech Connect

Almost all sources of high-energy particles and photons are associated with jet phenomena. Prominent sources of such highly relativistic outflows are pulsar winds, active galactic nuclei (AGNs), and gamma-ray bursts. The current understanding of these jets assumes diluted plasmas which are best described as kinetic phenomena. In this kinetic description, particle acceleration to ultrarelativistic speeds can occur in completely unmagnetized and neutral plasmas through insetting effects of instabilities. Even though the morphology and nature of particle spectra are understood to a certain extent, the composition of the jets is not known yet. While Poynting-flux-dominated jets (e.g., occurring in pulsar winds) are certainly composed of electron-positron plasmas, the understanding of the governing physics in AGN jets is mostly unclear. In this paper, we investigate how the constituting elements of an electron-positron-proton plasma behave differently under the variation of the fundamental mass ratio m{sub p} /m{sub e}. We initially studied unmagnetized counterstreaming plasmas using fully relativistic three-dimensional particle-in-cell simulations to investigate the influence of the mass ratio on particle acceleration and magnetic field generation in electron-positron-proton plasmas. We covered a range of mass ratios m{sub p}/m{sub e} between 1 and 100 with a particle number composition of n{sub p}{sup +}/ n{sub e}{sup +} of 1 in one stream, therefore called the pair-proton stream. Protons are injected in the other one, therefore from now on called the proton stream, whereas electrons are present in both to guarantee charge neutrality in the simulation box. We find that with increasing proton mass the instability takes longer to develop and for mass ratios >20 the particles seem to be accelerated in two phases which can be accounted for by the individual instabilities of the different species. This means that for high mass ratios the coupling between electrons/positrons and the heavier protons, which occurs in low mass ratios, disappears.

Burkart, Thomas; Elbracht, Oliver; Ganse, Urs; Spanier, Felix, E-mail: fspanier@astro.uni-wuerzburg.d [Lehrstuhl fuer Astronomie, Universitaet Wuerzburg, Am Hubland, D-97074 Wuerzburg (Germany)

2010-09-10T23:59:59.000Z

176

Acceleration  

NLE Websites -- All DOE Office Websites (Extended Search)

Acceleration Acceleration of porous media simulations on the Cray XE6 platform Kirsten M. Fagnan, Michael Lijewski, George Pau, Nicholas J. Wright Lawrence Berkeley National Laboratory 1 Cyclotron Road Berkeley, CA 94720 May 18, 2011 1 Introduction In this paper we investigate the performance of the Porous Media with Adaptive Mesh Refinment (PMAMR) code which was developed in the Center for Computational Science and Engineering at Lawrence Berkeley National Laboratory. This code is being used to model carbon sequestration and contaminant transport as part of the Advanced Simulation Capability for Environmental Management (ASCEM) project. The goal of the ASCEM project is to better understand and quantify flow and contaminant transport behavior in complex geological systems. It will also address the long-term performance of engineered components including cementitious materials in

177

Isotopic tracer studies of oxygen transport through SiO2 films at 1000?°C using secondary ion mass spectrometry  

Science Journals Connector (OSTI)

Dry oxides (?8 ppm H2O) grown on Si(100) at 1000?°C at 1 atm using purified 1 6O2 and purified 1 8O2 were analyzed using secondary ion mass spectrometry.1 8O is observed at the interface in the bulk of the 1 6O oxide and at the surface in agreement with other recent reports. Our results show little lattice diffusion in agreement with Mikkelsen’s work [Appl. Phys. Lett. 4 5 1187 (1984)]. A previous report [J. Electrochem. Soc. 1 3 1 1944 (1984)] of appreciable lattice diffusion is due to higher water content.

C. J. Han; C. R. Helms

1986-01-01T23:59:59.000Z

178

Determination of naphthenic acids in California crudes and refinery waste waters by fluoride ion chemical ionization mass spectrometry  

SciTech Connect

A method based on negative ion chemical ionization mass spectrometry using fluoride (F/sup -/) ions produced from NF/sub 3/ reagent gas has been applied to the analysis of naphthenic acids in California crude oils and refinery waste waters. Since complex mixtures of naphthenic acids cannot be separated into individual components, only the determination of relative distribution of acids classified by the hydrogen deficiency was possible. The identities and relative distribution of paraffinic and mono-, di-, tri, and higher polycyclic acids were obtained from the intensities of the carboxylate (RCOO/sup -/) ions.

Dzidic, I.; Somerville, A.C.; Raia, J.C.; Hart, H.V.

1988-07-01T23:59:59.000Z

179

Isotope correlations for determining the isotopic composition of plutonium produced in research and power reactors using the experimental data obtained by alpha and mass spectrometry  

Science Journals Connector (OSTI)

Correlations have been developed for obtaining the isotopic composition of Pu produced in Indian research (CIRUS, DHRUVA) and power (PHWR) reactors. The experimental data obtained on 238Pu/(239Pu + 240Pu) alpha activity ratio using alpha spectrometry and on 240Pu/239Pu, 241Pu/239Pu, 242Pu/239Pu atom ratios by thermal ionisation mass spectrometry were used for developing isotope correlations.

S.K. Aggarwal; D. Alamelu

2005-01-01T23:59:59.000Z

180

Time-Resolved Molecular Characterization of Limonene/Ozone Aerosol using High-Resolution Electrospray Ionization Mass Spectrometry  

SciTech Connect

Molecular composition of limonene/O3 secondary organic aerosol (SOA) was investigated using high-resolution electrospray ionization mass spectrometry (HR-ESI-MS) as a function of reaction time. SOA was generated by ozonation of D-limonene in a reaction chamber and sampled at different time intervals using a cascade impactor. The SOA samples were extracted into acetonitrile and analyzed using a HR-ESI-MS instrument with a resolving power of 100,000 (m/?m). The resulting mass spectra provided detailed information about the extent of oxidation inferred from the O:C ratios, double bond equivalency (DBE) factors, and aromaticity indexes (AI) in hundreds of identified individual SOA species.

Bateman, Adam P.; Nizkorodov, Serguei; Laskin, Julia; Laskin, Alexander

2009-09-09T23:59:59.000Z

Note: This page contains sample records for the topic "accelerator mass spectrometry" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Chemical Characterization of Crude Petroleum Using Nanospray Desorption Electrospray Ionization Coupled with High-Resolution Mass Spectrometry  

SciTech Connect

Nanospray desorption electrospray ionization (nano-DESI) combined with high-resolution mass spectrometry was used for the first time for the analysis of liquid petroleum crude oil samples. The analysis was performed in both positive and negative ionization modes using three solvents one of which (acetonitrile/toluene mixture) is commonly used in petroleomics studies while two other polar solvents (acetonitrile/water and methanol/water mixtures) are generally not compatible with petroleum characterization using mass spectrometry. The results demonstrate that nano-DESI analysis efficiently ionizes petroleum constituents soluble in a particular solvent. When acetonitrile/toluene is used as a solvent, nano-DESI generates electrospray-like spectra. In contrast, strikingly different spectra were obtained using acetonitrile/water and methanol/water. Comparison with the literature data indicates that these solvents selectively extract water-soluble constituents of the crude oil. Water-soluble compounds are predominantly observed as sodium adducts in nano-DESI spectra indicating that addition of sodium to the solvent may be a viable approach for efficient ionization of water-soluble crude oil constituents. Nano-DESI enables rapid screening of different classes of compounds in crude oil samples using solvents that are rarely used for petroleum characterization.

Eckert, Peter A.; Roach, Patrick J.; Laskin, Alexander; Laskin, Julia

2012-02-07T23:59:59.000Z

182

Calibration of laser ablation inductively coupled plasma mass spectrometry using dried solution aerosols for the quantitative analysis of solid samples  

SciTech Connect

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.

Leach, J.

1999-02-12T23:59:59.000Z

183

Determination of boron traces in rye grass BCR 281 by isotope dilution mass spectrometry  

Science Journals Connector (OSTI)

A method for the isotope dilution mass spectrometric (IDMS) determination of boron in rye grass at the 5 ?g...?1 level has been developed. The mass spectrometric measurements are performed using negative thermal ...

A. Lamberty; V. Holland; A. Verbruggen…

1988-01-01T23:59:59.000Z

184

High Precision Atomic Mass Spectrometry with Applications to Neutrino Physics, Fundamental Constants and Physical Chemistry.  

E-Print Network (OSTI)

?? The Florida State University single-ion cryogenic Penning trap mass spectrometer has been used to precisely measure the masses of the doublets 76Ge/76Se and 74Ge/74Se… (more)

Mount, Brianna Jane

2010-01-01T23:59:59.000Z

185

Accelerating an Water Maser Face-on Jet from a High Mass Young Stellar Object  

E-Print Network (OSTI)

We report on a long-term single-dish and VLBI monitoring for intermittent flare activities of a Dominant Blue-Shifted H$_{2}$O Maser (DBSM) associated with a southern high mass young stellar object, G353.273+0.641. Bi-weekly single-dish monitoring using Hokkaido University Tomakomai 11-m radio telescope has shown that a systematic acceleration continues over four years beyond a lifetime of individual maser features. This fact suggests that the H$_{2}$O maser traces a region where molecular gas is steadily accelerated. There were five maser flares during five-years monitoring, and maser distributions in four of them were densely monitored by the VLBI Exploration of Radio Astrometry (VERA). The overall distribution of the maser features suggests the presence of a bipolar jet, with the 3D kinematics indicating that it is almost face-on (inclination angle of $\\sim$ 8$^{\\fdg}$--17$^{\\fdg}$ from the line-of-sight). Most of maser features were recurrently excited within a region of 100$\\times$100 AU$^{2}$ around the...

Motogi, Kazuhito; Honma, Mareki; Hirota, Tomoya; Hachisuka, Kazuya; Niinuma, Kotaro; Sugiyama, Koichiro; Yonekura, Yosinori; Fujisawa, Kenta

2015-01-01T23:59:59.000Z

186

Slurry Nebulization-Inductively Coupled Plasma Mass Spectrometry with Solution Calibration for Determination of Ultratrace Boron in High Pure Nuclear Graphite Powder  

Science Journals Connector (OSTI)

Slurry nebulization-inductively coupled plasma mass spectrometry (ICP-MS) was developed for the direct determination of trace boron (B) in high-purity graphite powders. After the graphite powders were ground and sifted, the particle size of graphite was collected less than 5 ?m. Polyvinylpyrrolidone (PVP) was used as the dispersant in slurry preparation. The optimal mass ratio of PVP to the graphite was found to be 0.5. Well-proportioned and stable slurry solution was obtained by magnetic stirrer. 0.1 M NH4OH as the aqueous medium could provide the optimal pH of 10 for the stable slurry and eliminate the memory effect of B. ICP-MS was operated in a higher resolution mode (0.6 amu) to eliminate the interference with the matrix 12C by peak tailing. Oxygen was added into the plasma at a flow rate of 60 mL min?1 to resolve carbon deposition on the sampler and skimmer cones and accelerate particle dissociation in the plasma. External calibration with aqueous solution standards was established for quantification. Beryllium was chosen as the internal standard to evaluate the efficiency of matrix effect correction. A correlation coefficient of 0.9995 was obtained for B concentration ranging 2–200 ?g L?1. The detection limit (3S) of B was 0.095 ?g g?1. As a practical application, the proposed method was used for the determination of trace B in four nuclear graphite samples (claimed 99.999% purity), with the satisfactory recoveries for the spike tests in the range of 97.2%–103.1%.

Xin-Li LIU; Tai-Cheng DUAN; Yi HAN; Xiao-Yu JIA; Wei-Na ZHANG; Hang-Ting CHEN

2010-01-01T23:59:59.000Z

187

Isobar separation by time-of-flight mass spectrometry for low-energy radioactive ion beam facilities  

Science Journals Connector (OSTI)

A multiple-reflection time-of-flight mass spectrometer (MR-TOF-MS) system for low-energy radioactive ion beam facilities has been developed, which can be used for (i) isobar separation and (ii) direct mass measurements of very short-lived nuclei with half-lives of about 1 ms or longer, and (iii) for identification and diagnosis of the ion beam by mass spectrometry. The system has been designed and simulated, and individual subsystems have been built and characterized experimentally. An injection trap for cooling and bunching of the ion beam has been developed, and cooling times of less than one millisecond have been achieved. The performance of the MR-TOF-MS was characterized using the isobaric doublet of carbon monoxide and nitrogen molecular ions. A mass resolving power of 105 (FWHM) has been obtained even with an uncooled ion population. The separator capabilities of the MR-TOF-MS have been demonstrated by removing either carbon monoxide or nitrogen ions from the beam in a Bradbury-Nielsen Gate after a flight time of 320 ?s. The separation power achieved is thus at least 7000 (FWHM) and increases for longer time-of-flight. An energy buncher stage has been designed that compresses the energy spread of the beam after the separation and facilitates efficient injection of the selected ions into an accumulation trap prior to transfer of the ions to experiments downstream of the MR-TOF-MS.

Wolfgang R. Plaß; Timo Dickel; Ulrich Czok; Hans Geissel; Martin Petrick; Katrin Reinheimer; Christoph Scheidenberger; Mikhail I.Yavor

2008-01-01T23:59:59.000Z

188

Consecutive Ion Activation for Top Down Mass Spectrometry:? Improved Protein Sequencing by Nozzle?Skimmer Dissociation  

Science Journals Connector (OSTI)

Mass spectra produced by nozzle?skimmer dissociation (NSD) have been little used in the past for structural characterization. NSD cannot be used on mass-separated ions (MS/MS), and for electrosprayed protein ions, previous NSD spectra showed backbone ...

Huili Zhai; Xuemei Han; Kathrin Breuker; Fred W. McLafferty

2005-08-20T23:59:59.000Z

189

Electrospray ionization–tandem mass spectrometry analysis of phospholipid molecular species from Antarctic and non-Antarctic yeasts  

Science Journals Connector (OSTI)

Abstract High performance liquid chromatography-electrospray ionization tandem mass spectrometry was applied to the comprehensive analysis of phospholipids from seven Antarctic and seven non-Antarctic yeasts. Identification of specific fatty acyl moieties to the sn-1 and sn-2 positions of phosphatidylethanolamine (PE), phosphatidylcholine (PC), phosphatidylserine (PS) and phosphatidylinositol (PI) were determined by relative abundance of fragment ions associated with formation of carboxylate anions and loss of fragment ions as free fatty carboxylic acid and ketene. Modulations with growth temperature in fatty acyl moieties in the sn-1 and sn-2 positions were characterized. Principal component analysis demonstrated that PE, PC and to a lesser extent PS, but not PI, were grouped into three distinct clusters consisting of seven Antarctic yeasts (Cryptococcus victoriae, Holtermanniella wattica, H. nyarrowii, Candida psychrophila, Leucosporidium fellii, Glaciozyma antarctica, Rhodotorula mucilaginosa), four non-Antarctic yeasts (C. albicans, Zygosaccharomyces rouxii, Cr. humicolus, R. mucilaginosa) and three strains of Saccharomyces cerevisiae.

Mohammad Bhuiyan; David Tucker; Kenneth Watson

2014-01-01T23:59:59.000Z

190

Improving the Sensitivity of Mass Spectrometry by Using a New Sheath Flow Electrospray Emitter Array at Subambient Pressures  

SciTech Connect

Arrays of chemically etched emitters with individualized sheath gas capillaries have been developed to enhance electrospray ionization (ESI) at subambient pressures. By including an emitter array in a subambient pressure ionization with nanoelectrospray (SPIN) source, ionization and transmission efficiency can be maximized allowing for increased sensitivity in mass spectrometric analyses. The SPIN source eliminates the major ion losses at conventional ESI-mass spectrometry (MS) interface by placing the emitter in the first vacuum region of the instrument. To facilitate stable electrospray currents in such conditions we have developed an improved emitter array with individualized sheath gas around each emitter. The utility of the new emitter arrays for generating stable multi-electrosprays at subambient pressures was probed by coupling the emitter array/SPIN source with a time of flight (TOF) mass spectrometer. The instrument sensitivity was compared between single emitter/SPIN-MS and multi-emitter/SPIN-MS configurations using an equimolar solution of 9 peptides. An increase in sensitivity correlative to the number of emitters in the array was observed.

Cox, Jonathan T.; Marginean, Ioan; Kelly, Ryan T.; Smith, Richard D.; Tang, Keqi

2014-12-01T23:59:59.000Z

191

Measurement of positional isotope exchange rates in enzyme catalyzed reactions by fast atom bombardment mass spectrometry  

E-Print Network (OSTI)

OF FIGURES Page Figure 1. Fast atom bombardment mass spectra of ANP from acetyl CoA synthetase PIX reactions 25 Figure 2. Fast atom bombardment mass spectra of ATP rath 18 various amounts of 0 Figure 3. Fast atom bombardment mass spectra of ANP from... of this phosphate was the result of P-y bridge to 0-non- bridge PK within the labelled ATP molecule. Through reaction rath diazcmcthane the inorganic phosphate was converted to methyl phosphate. Finally this volatile derivative was analyzed mth gas...

Hilscher, Larry Wayne

2012-06-07T23:59:59.000Z

192

Principal ComponentAnalysisof Optical EmissionSpectroscopy and MassSpectrometry:Applicationto Reactive Ion Etch  

E-Print Network (OSTI)

of process parameters (i.e., pressure, RF power, and gas mixture) on the optical emission and mass spectra.g., chamber pressure, RF power, and gas flow, while others are internal to the condition of the chamber, e

Shadmehr, Reza

193

Determination of particulate lead using aerosol mass spectrometry: MILAGRO/MCMA-2006 observations  

E-Print Network (OSTI)

We report the first measurements of particulate lead (Pb) from Aerodyne Aerosol Mass Spectrometers, which were deployed in and around Mexico City during the Megacity Initiative: Local and Global Research Observations ...

Salcedo, D.

194

Molecular beam mass spectrometry with tunable vacuum ultraviolet (VUV) synchrotron radiation  

E-Print Network (OSTI)

photoionization efficiency (PIE) curve can be plotted whicha photoionization efficiency curve (PIE) 3.1) Using the ALSto mass. 3.8) To plot a PIE curve, one easy way is to use a

Golan, Amir

2014-01-01T23:59:59.000Z

195

New Mass and Lifetime Measurements of $^{152}$Sm Projectile Fragments with Time-Resolved Schottky Mass Spectrometry  

E-Print Network (OSTI)

The FRS-ESR facilities at GSI provide unique conditions for precision measurements with stored exotic nuclei over a large range in the chart of nuclides. In the present experiment the exotic nuclei were produced via fragmentation of $^{152}$Sm projectiles in a thick beryllium target at 500-600 MeV/u, separated in-flight with the fragment separator FRS, and injected into the storage-cooler ring ESR. Mass and lifetime measurements have been performed with bare and few-electron ions. The experiment and first results will be presented in this contribution.

Yu. A. Litvinov; F. Bosch; H. Geissel; H. Weick; K. Beckert; P. Beller; D. Boutin; C. Brandau; L. Chen; O. Klepper; R. Knöbel; C. Kozhuharov; J. Kurcewicz; S. A. Litvinov; M. Mazzocco; G. Münzenberg; C. Nociforo; F. Nolden; W. Plaß; C. Scheidenberger; M. Steck; B. Sun; M. Winkler

2005-09-15T23:59:59.000Z

196

Impurity Profiling of a Chemical Weapon Precursor for Possible Forensic Signatures by Comprehensive Two-Dimensional Gas Chromatography/Mass Spectrometry and Chemometrics  

Science Journals Connector (OSTI)

Impurity Profiling of a Chemical Weapon Precursor for Possible Forensic Signatures by Comprehensive Two-Dimensional Gas Chromatography/Mass Spectrometry and Chemometrics ... DMMP is a widely used flame retardant(6, 7) that is listed as a schedule 2 compound by the Chemical Weapons Convention (CWC) because it is a well-known CW precursor and not produced in large quantities for commercial purposes. ...

Jamin C. Hoggard; Jon H. Wahl; Robert E. Synovec; Gary M. Mong; Carlos G. Fraga

2009-12-16T23:59:59.000Z

197

Phenotypic Detection of Carbapenemase-Producing Enterobacteriaceae by Use of Matrix-Assisted Laser Desorption Ionization–Time of Flight Mass Spectrometry and the Carba NP Test  

Science Journals Connector (OSTI)

...Flight Mass Spectrometry and the Carba NP Test James Knox a Snehal Jadhav b Danielle Sevior...the diagnostic accuracy of the Carba NP test with that of a straightforward matrix-assisted...Using PCR as the reference method, both tests demonstrated a sensitivity of 87% and...

James Knox; Snehal Jadhav; Danielle Sevior; Alex Agyekum; Margaret Whipp; Lynette Waring; Jonathan Iredell; Enzo Palombo

2014-09-03T23:59:59.000Z

198

Aerosol Mass Spectrometry via Laser-Induced Incandescence Particle Vaporization Final Report  

SciTech Connect

We have successfully developed and commercialized a soot particle aerosol mass spectrometer (SP-AMS) instrument to measure mass, size, and chemical information of soot particles in ambient environments. The SP-AMS instrument has been calibrated and extensively tested in the laboratory and during initial field studies. The first instrument paper describing the SP-AMS has been submitted for publication in a peer reviewed journal and there are several related papers covering initial field studies and laboratory studies that are in preparation. We have currently sold 5 SP-AMS instruments (either as complete systems or as SP modules to existing AMS instrument operators).

Timothy B. Onasch

2011-10-20T23:59:59.000Z

199

Precise ruthenium fission product isotopic analysis using dynamic reaction cell inductively coupled plasma mass spectrometry (DRC-ICP-MS)  

SciTech Connect

99Tc is a subsurface contaminant of interest at numerous federal, industrial, and international facilities. However, as a mono-isotopic fission product, 99Tc lacks the ability to be used as a signature to differentiate between the different waste disposal pathways that could have contributed to subsurface contamination at these facilities. Ruthenium fission-product isotopes are attractive analogues for the characterization of 99Tc sources because of their direct similarity to technetium with regard to subsurface mobility, and their large fission yields and low natural background concentrations. We developed an inductively coupled plasma mass spectrometry (ICP-MS) method capable of measuring ruthenium isotopes in groundwater samples and extracts of vadose zone sediments. Samples were analyzed directly on a Perkin Elmer ELAN DRC II ICP-MS after a single pass through a 1-ml bed volume of Dowex AG 50W-X8 100-200 mesh cation exchange resin. Precise ruthenium isotopic ratio measurements were achieved using a low-flow Meinhard-type nebulizer and long sample acquisition times (150,000 ms). Relative standard deviations of triplicate replicates were maintained at less than 0.5% when the total ruthenium solution concentration was 0.1 ng/ml or higher. Further work was performed to minimize the impact caused by mass interferences using the dynamic reaction cell (DRC) with O2 as the reaction gas. The aqueous concentrations of 96Mo and 96Zr were reduced by more than 99.7% in the reaction cell prior to injection of the sample into the mass analyzer quadrupole. The DRC was used in combination with stable-mass correction to quantitatively analyze samples containing up to 2-orders of magnitude more zirconium and molybdenum than ruthenium. The analytical approach documented herein provides an efficient and cost-effective way to precisely measure ruthenium isotopes and quantitate total ruthenium (natural vs. fission-product) in aqueous matrixes.

Brown, Christopher F.; Dresel, P. Evan; Geiszler, Keith N.; Farmer, Orville T.

2006-05-09T23:59:59.000Z

200

Laser vaporization/ionization interface for coupling microscale separation techniques with mass spectrometry  

DOE Patents (OSTI)

The present invention provides a laser-induced vaporization and ionization interface for directly coupling microscale separation processes to a mass spectrometer. Vaporization and ionization of the separated analytes are facilitated by the addition of a light-absorbing component to the separation buffer or solvent. 8 figs.

Yeung, E.S.; Chang, Y.C.

1999-06-29T23:59:59.000Z

Note: This page contains sample records for the topic "accelerator mass spectrometry" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Combining Laser Ablation/Liquid Phase Collection Surface Sampling and High-Performance Liquid Chromatography Electrospray Ionization Mass Spectrometry  

SciTech Connect

This paper describes the coupling of ambient pressure transmission geometry laser ablation with a liquid phase sample collection method for surface sampling and ionization with subsequent mass spectral analysis. A commercially available autosampler was adapted to produce a liquid droplet at the end of the syringe injection needle while in close proximity to the surface to collect the sample plume produced by laser ablation. The sample collection was followed by either flow injection or a high performance liquid chromatography (HPLC) separation of the extracted components and detection with electrospray ionization mass spectrometry (ESI-MS). To illustrate the analytical utility of this coupling, thin films of a commercial ink sample containing rhodamine 6G and of mixed isobaric rhodamine B and 6G dyes on glass microscope slides were analyzed. The flow injection and HPLC/ESI-MS analysis revealed successful laser ablation, capture and, with HPLC, the separation of the two compounds. The ablated circular area was about 70 m in diameter for these experiments. The spatial sampling resolution afforded by the laser ablation, as well as the ability to use sample processing methods like HPLC between the sample collection and ionization steps, makes this combined surface sampling/ionization technique a highly versatile analytical tool.

Ovchinnikova, Olga S [ORNL; Kertesz, Vilmos [ORNL; Van Berkel, Gary J [ORNL

2011-01-01T23:59:59.000Z

202

Cadmium binding studies to the earthworm Lumbricus rubellus metallothionein by electrospray mass spectrometry and circular dichroism spectroscopy  

SciTech Connect

The earthworm Lumbricus rubellus has been found to inhabit cadmium-rich soils and accumulate cadmium within its tissues. Two metallothionein (MT) isoforms (1 and 2) have been identified and cloned from L. rubellus. In this study, we address the metalation status, metal coordination, and structure of recombinant MT-2 from L. rubellus using electrospray ionization mass spectrometry (ESI-MS), UV absorption, and circular dichroism (CD) spectroscopy. This is the first study to show the detailed mass and CD spectral properties for the important cadmium-containing earthworm MT. We report that the 20-cysteine L. rubellus MT-2 binds seven Cd{sup 2+} ions. UV absorption and CD spectroscopy and ESI-MS pH titrations show a distinct biphasic demetalation reaction, which we propose results from the presence of two metal-thiolate binding domains. We propose stoichiometries of Cd{sub 3}Cys{sub 9} and Cd{sub 4}Cys{sub 11} based on the presence of 20 cysteines split into two isolated regions of the sequence with 11 cysteines in the N-terminal and 9 cysteines in the C-terminal. The CD spectrum reported is distinctly different from any other metallothionein known suggesting quite different binding site structure for the peptide.

Ngu, Thanh T. [Department of Chemistry, University of Western Ontario, London, Ont., N6A 5B7 (Canada); Sturzenbaum, Stephen R. [School of Biomedical and Health Sciences, King's College, London, SE1 9NH (United Kingdom); Stillman, Martin J. [Department of Chemistry, University of Western Ontario, London, Ont., N6A 5B7 (Canada)]. E-mail: Martin.Stillman@uwo.ca

2006-12-08T23:59:59.000Z

203

Reduction of plyatomic ion interferences in indictively coupled plasma mass spectrometry with cryogenic desolvation  

SciTech Connect

A desolvation scheme for introducing aqueous and organic samples into an argon inductively coupled plasma is described; the aerosol generated by nebulizer is heated (+140 C) and cooled ({minus}80 C) repeatedly, and the dried aerosol is then injected into the mass spectrometer. Polyatomic ions are greatly suppressed. This scheme was validated with analysis of seawater and urine reference samples. Finally, the removal of organic solvents by cryogenic desolvation was studied.

Alves, L.C.

1993-09-01T23:59:59.000Z

204

Qualitative and quantitative analysis of proteolytically digested glycoproteins by mass spectrometry  

E-Print Network (OSTI)

analytes simultaneously. Examples of mass analyzers include ion traps (3-D or 2-D), triple quadrupole, time of flight (TOF), Fourier transform – ion cyclotron resonance (FT-ICR), 14 and, most recently, the orbitrap.76, 77 Each of these analyzers has... is heated to approximately 200 °C, causing the solvent in the charged droplets to evaporate. A combination of solvent evaporation and Coulombic fission, due to increased space charge effects of the ions in the droplets as evaporation is occurring, allows...

Rebecchi, Kathryn

2011-05-31T23:59:59.000Z

205

Determination of thorium in seawater by neutron activation analysis and mass spectrometry  

SciTech Connect

The recent development of neutron activation analysis and mass spectrometric methods for the determination of /sup 232/Th in seawater has made possible rapid sampling and analysis of this long-lived, non-radiogenic thorium isotope on small-volume samples. The marine geochemical utility of /sup 232/Th, whose concentration in seawater is extremely low, warrants the development of these sensitive techniques. The analytical methods and some results are presented and discussed in this article. 24 refs., 3 figs.

Huh, Chih-An

1987-01-01T23:59:59.000Z

206

Inductively Coupled Plasma Mass Spectrometry and Atomic Emission Spectrometry Coupled to High-Performance Liquid Chromatography for Speciation and Detection of Organotin Compounds  

Science Journals Connector (OSTI)

......graphite furnace atomic absorption ( G F A A ) , flame atomic...fluent is monitored by atomic absorption (20-22). In this study...8 C with a re frigerated chiller (Neslab Instrument, Inc...gas chromatography atomic absorption spectrometry. Anal. Chem......

Hamzar Suyani; John Creed; Tim Davidson; Joseph Caruso

1989-03-01T23:59:59.000Z

207

Final LDRD report : development of sample preparation methods for ChIPMA-based imaging mass spectrometry of tissue samples.  

SciTech Connect

The objective of this short-term LDRD project was to acquire the tools needed to use our chemical imaging precision mass analyzer (ChIPMA) instrument to analyze tissue samples. This effort was an outgrowth of discussions with oncologists on the need to find the cellular origin of signals in mass spectra of serum samples, which provide biomarkers for ovarian cancer. The ultimate goal would be to collect chemical images of biopsy samples allowing the chemical images of diseased and nondiseased sections of a sample to be compared. The equipment needed to prepare tissue samples have been acquired and built. This equipment includes an cyro-ultramicrotome for preparing thin sections of samples and a coating unit. The coating unit uses an electrospray system to deposit small droplets of a UV-photo absorbing compound on the surface of the tissue samples. Both units are operational. The tissue sample must be coated with the organic compound to enable matrix assisted laser desorption/ionization (MALDI) and matrix enhanced secondary ion mass spectrometry (ME-SIMS) measurements with the ChIPMA instrument Initial plans to test the sample preparation using human tissue samples required development of administrative procedures beyond the scope of this LDRD. Hence, it was decided to make two types of measurements: (1) Testing the spatial resolution of ME-SIMS by preparing a substrate coated with a mixture of an organic matrix and a bio standard and etching a defined pattern in the coating using a liquid metal ion beam, and (2) preparing and imaging C. elegans worms. Difficulties arose in sectioning the C. elegans for analysis and funds and time to overcome these difficulties were not available in this project. The facilities are now available for preparing biological samples for analysis with the ChIPMA instrument. Some further investment of time and resources in sample preparation should make this a useful tool for chemical imaging applications.

Maharrey, Sean P.; Highley, Aaron M.; Behrens, Richard, Jr.; Wiese-Smith, Deneille

2007-12-01T23:59:59.000Z

208

Xlink-Identifier: An Automated Data Analysis Platform for Confident Identifications of Chemically Cross-linked Peptides using Tandem Mass Spectrometry  

SciTech Connect

Chemical cross-linking combined with mass spectrometry provides a powerful method for identifying protein-protein interactions and probing the structure of protein complexes. Cross-linking is the process of covalently joining two proteins using cross-linking reagents. After proteolytic cleavage, the cross-linked peptides can be identified using tandem mass spectrometry. A number of strategies have been reported that take advantage of the high sensitivity and high resolution of modern mass spectrometers. Approaches typically include synthesis of novel cross-linking compounds and/or isotopic labelling of the cross-linkering reagent and/or protein to aid both identification and quantitation. However, these approaches have various limitations. These limitations can be overcome with a label-free approach and application of associated data analysis algorithms described in this work.

Du, Xiuxia; Chowdhury, Saiful M.; Manes, Nathan P.; Wu, Si; Mayer, M. Uljana; Adkins, Joshua N.; Anderson, Gordon A.; Smith, Richard D.

2011-03-04T23:59:59.000Z

209

Determination of Boron in Coal Using Closed-Vessel Microwave Digestion and Inductively Coupled Plasma Mass Spectrometry (ICP-MS)  

Science Journals Connector (OSTI)

Previous studies indicate that boron in coal has been mostly determined by atomic emission spectroscopy (AES) or inductively coupled plasma–atomic emission spectrometry (ICP-AES). ... The results (Figure 1) indicated that a 2% ammonia solution can effectively eliminate the boron memory effect and reduce boron signals to blank levels (within 120 s), similar to analytical results obtained by Al-Ammar et al.(54) and Huang et al.(55) The boron memory effect is not attributed to the skimmer, sampler, or other mass spectrometer components, but originates from the tendency of boron to volatilize as boric acid from the sample solution that covers the inside surface of the ICP-MS spray chamber. ... Using different online additions of internal standard solutions, the observed boron concentrations based on the 10B and 11B spectral lines are close to each other, indicating that the observed boron concentrations based on the two isotope spectral lines are both suitable for determination of boron in coal. ...

Shifeng Dai; Weijiao Song; Lei Zhao; Xiao Li; James C. Hower; Colin R. Ward; Peipei Wang; Tian Li; Xin Zheng; Vladimir V. Seredin; Panpan Xie; Qingqian Li

2014-06-23T23:59:59.000Z

210

Quantifying Uranium Isotope Ratios Using Resonance Ionization Mass Spectrometry: The Influence of Laser Parameters on Relative Ionization Probability  

SciTech Connect

Resonance Ionization Mass Spectrometry (RIMS) has been developed as a method to measure relative uranium isotope abundances. In this approach, RIMS is used as an element-selective ionization process to provide a distinction between uranium atoms and potential isobars without the aid of chemical purification and separation. We explore the laser parameters critical to the ionization process and their effects on the measured isotope ratio. Specifically, the use of broad bandwidth lasers with automated feedback control of wavelength was applied to the measurement of {sup 235}U/{sup 238}U ratios to decrease laser-induced isotopic fractionation. By broadening the bandwidth of the first laser in a 3-color, 3-photon ionization process from a bandwidth of 1.8 GHz to about 10 GHz, the variation in sequential relative isotope abundance measurements decreased from >10% to less than 0.5%. This procedure was demonstrated for the direct interrogation of uranium oxide targets with essentially no sample preparation. A rate equation model for predicting the relative ionization probability has been developed to study the effect of variation in laser parameters on the measured isotope ratio. This work demonstrates that RIMS can be used for the robust measurement of uranium isotope ratios.

Isselhardt, B H

2011-09-06T23:59:59.000Z

211

Electrospray mass spectrometry of NeuAc oligomers associated with the C fragment of the tetanus toxin  

SciTech Connect

The Clostridial neurotoxins, botulinum and tetanus, gain entry into neuronal cells by protein recognition involving cell specific binding sites. The sialic or N-acetylneuraminic acid (NeuAc) residues of gangliosides attached to the surface of motor neurons are the suspected recognition and interaction points with Clostridial neurotoxins, although not necessarily the only ones. We have used electrospray ionization mass spectrometry (ESIMS) to examine formation of complexes between the tetanus toxin C fragment, or targeting domain, and carbohydrates containing NeuAc groups to determine how NeuAc residues contribute to ganglioside binding. ESI-MS was used to rapidly and efficiently measure dissociation constants for a number of related NeuAc-containing carbohydrates and NeuAc oligomers, information that has helped identify the structural features of gangliosides that determine their binding to tetanus toxin. The strength of the interactions between the C fragment and (NeuAc){sub n}, are consistent with the topography of the targeting domain of tetanus toxin and the nature of its carbohydrate binding sites. The results suggest that the targeting domain of tetanus toxin contains two binding sites that can accommodate NeuAc (or a dimer). This study also shows that NeuAc must play an important role in ganglioside binding and molecular recognition, a process critical for normal cell function and one frequently exploited by toxins, bacteria and viruses to facilitate their entrance into cells.

Prieto, M C; Whittal, R M; Baldwin, M A; Burlingame, A L; Balhorn, R

2005-04-03T23:59:59.000Z

212

Determination of secondary ion mass spectrometry relative sensitivity factors for polar and non-polar ZnO  

SciTech Connect

Zinc oxide (ZnO) is regarded as a promising material for optoelectronic devices, due to its electronic properties. Solely, the difficulty in obtaining p-type ZnO impedes further progress. In this connection, the identification and quantification of impurities is a major demand. For quantitative information using secondary ion mass spectrometry (SIMS), so-called relative sensitivity factors (RSF) are mandatory. Such conversion factors did not yet exist for ZnO. In this work, we present the determined RSF values for ZnO using primary (ion implanted) as well as secondary (bulk doped) standards. These RSFs have been applied to commercially available ZnO substrates of different surface termination (a-plane, Zn-face, and O-face) to quantify the contained impurities. Although these ZnO substrates originate from the same single-crystal, we observe discrepancies in the impurity concentrations. These results cannot be attributed to surface termination dependent RSF values for ZnO.

Laufer, Andreas; Volbers, Niklas; Eisermann, Sebastian; Meyer, Bruno K. [Physikalisches Institut, Justus-Liebig-Universitaet Giessen, Heinrich-Buff-Ring 16, 35392 Giessen (Germany); Potzger, Kay [Helmholtz-Zentrum Dresden-Rossendorf, Bautzner Landstrasse 400, 01328 Dresden (Germany); Geburt, Sebastian; Ronning, Carsten [Institut fuer Festkoerperphysik, Universitaet Jena, Max-Wien-Platz 1, 07743 Jena (Germany)

2011-11-01T23:59:59.000Z

213

Standard test method for determination of impurities in nuclear grade uranium compounds by inductively coupled plasma mass spectrometry  

E-Print Network (OSTI)

1.1 This test method covers the determination of 67 elements in uranium dioxide samples and nuclear grade uranium compounds and solutions without matrix separation by inductively coupled plasma mass spectrometry (ICP-MS). The elements are listed in Table 1. These elements can also be determined in uranyl nitrate hexahydrate (UNH), uranium hexafluoride (UF6), triuranium octoxide (U3O8) and uranium trioxide (UO3) if these compounds are treated and converted to the same uranium concentration solution. 1.2 The elements boron, sodium, silicon, phosphorus, potassium, calcium and iron can be determined using different techniques. The analyst's instrumentation will determine which procedure is chosen for the analysis. 1.3 The test method for technetium-99 is given in Annex A1. 1.4 The values stated in SI units are to be regarded as standard. 1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish ...

American Society for Testing and Materials. Philadelphia

2010-01-01T23:59:59.000Z

214

Characterization of a Sealed Americium-Beryllium (AmBe) Source by Inductively Coupled Plasma Mass Spectrometry  

SciTech Connect

Two Americium-Beryllium neutron sources were dismantled, sampled (sub-sampled) and analyzed via inductively coupled plasma mass spectrometry (ICP-MS). Characteristics such as “age” since purification, actinide content, trace metal content and inter and intra source composition were determined. The “age” since purification of the two sources was determined to be 25.0 and 25.4 years, respectively. The systematic errors in the “age” determination were ± 4 % 2s. The amount and isotopic composition of U and Pu varied substantially between the sub-samples of Source 2 (n=8). This may be due to the physical means of sub-sampling or the way the source was manufactured. Source 1 was much more consistent in terms of content and isotopic composition (n=3 sub-samples). The Be-Am ratio varied greatly between the two sources. Source 1 had an Am-Be ratio of 6.3 ± 52 % (1s). Source 2 had an Am-Be ratio of 9.81 ± 3.5 % (1s). In addition, the trace element content between the samples varied greatly. Significant differences were determined between Source 1 and 2 for Sc, Sr, Y, Zr, Mo, Ba and W.

James Sommers; Marcos Jimenez; Mary Adamic; Jeffrey Giglio; Kevin Carney

2009-12-01T23:59:59.000Z

215

Observation of a small oligonucleotide duplex by electrospray ionization mass spectrometry  

SciTech Connect

Electrospray ionization (ESI) has been demonstrated to be a soft ionization technique, allowing accurate molecular weight determination for biopolymers due to gas-phase multiple charging. Recent results have demonstrated that noncovalent associations can be preserved upon transfer into the gas phase with ESI, providing a new approach to the determination of both structurally-specific and nonspecific noncovalent associations in solution. The mass spectrometric experimental conditions necessary to preserve such noncovalent associations, and the physical constraints upon such, have yet to be elucidated, although it is clear that gentle interface conditions minimizing internal excitation of noncovalent complexes are helpful. Base-paired oligonucleotide hybridization constitutes one of the most important and thoroughly studied noncovalent associations of biopolymers. Initial attempts to observe duplex oligonucleotides resulted in detection of only the monomeric constituents. Since then, the authors have developed interface conditions that are more gentle and yet still provide sufficient molecular ion desolvation to preserve such associations using new instrumentation with a greatly extended m/z range. In this communication, the authors report the successful ionization of duplex oligonucleotides and the conditions necessary for detection by negative ion ESI-MS. 6 refs., 1 fig.

Light-Wahl, K.J.; Springer, D.L.; Winger, B.E.; Edmonds, C.G.; Thrall, B.D.; Smith, R.D. (Pacific Northwest Lab., Richland, WA (United States)); Camp, D.G. II (Eastern Oregon State College, La Grande (United States))

1993-01-27T23:59:59.000Z

216

Detection of Chemical/Biological Agents and Stimulants using Quadrupole Ion Trap Mass Spectrometry  

SciTech Connect

Detection of Chemical/Biological Agents and Simulants A new detector for chemical and biological agents is being developed for the U. S. Army under the Chemical and Biological Mass Spectrometer Block II program. The CBMS Block II is designed to optimize detection of both chemical and biological agents through the use of direct sampling inlets [I], a multi- ported sampling valve and a turbo- based vacuum system to support chemical ionization. Unit mass resolution using air as the buffer gas [2] has been obtained using this design. Software to control the instrument and to analyze the data generated from the instrument has also been newly developed. Detection of chemical agents can be accomplished. using the CBMS Block II design via one of two inlets - a l/ I 6'' stainless steel sample line -Chemical Warfare Air (CW Air) or a ground probe with enclosed capillary currently in use by the US Army - CW Ground. The Block II design is capable of both electron ionization and chemical ionization. Ethanol is being used as the Cl reagent based on a study indicating best performance for the Biological Warfare (BW) detection task (31). Data showing good signal to noise for 500 pg of methyl salicylate injected into the CW Air inlet, 50 ng of dimethylmethylphosphonate exposed to the CW Ground probe and 5 ng of methyl stearate analyzed using the pyrolyzer inlet were presented. Biological agents are sampled using a ''bio-concentrator'' unit that is designed to concentrate particles in the low micron range. Particles are collected in the bottom of a quartz pyrolyzer tube. An automated injector is being developed to deliver approximately 2 pL of a methylating reagent, tetramethylamonium- hydroxide to 'the collected particles. Pyrolysis occurs by rapid heating to ca. 55OOC. Biological agents are then characterized by their fatty acid methyl ester profiles and by other biomarkers. A library of ETOH- Cl/ pyrolysis MS data of microorganisms used for a recently published study [3] has been expanded with additional bacteria and fungi. These spectra were acquired on a Finnigan Magnum ion trap using helium buffer gas. A new database of Cl spectra of microorganisms is planned using the CBMS Block II instrument and air as the buffer gas. Using the current database, the fatty acid composition of the organisms was compared using the percentage of the ion current attributable to fatty acids. The data presented suggest promising rules for discrimination of these organisms. Strain, growth media and vegetative state do contribute to some of the distributions observed in the data. However, the data distributions observed in the current study only reflect our experience to date and do not fully represent the variability that might be expected in practice: Acquisition of MS/ MS spectra has begun (using He and air buffer gas) of the protonated molecular ion of a variety of fatty acids and for a number of ions nominally assigned as fatty acids from microorganisms. These spectra will be used to help verify fatty acid .

Harmon, S.H.; Hart, K.J.; Vass, A.A.; Wise, M.B.; Wolf, D.A.

1999-06-14T23:59:59.000Z

217

1,5-Diaminonaphthalene Hydrochloride Assisted Laser Desorption/Ionization Mass Spectrometry Imaging of Small Molecules in Tissues Following Focal Cerebral Ischemia  

Science Journals Connector (OSTI)

In the present study, 1,5-naphthalenediamine (1,5-DAN) hydrochloride was prepared for matrix-assisted laser desorption/ionization (MALDI) mass spectrometry imaging (MSI) of small molecules in liver, brain, and kidneys from mice. ... Rat brains were removed and immediately frozen under ?80 °C. ... In this study, we conducted IMS on rat brains damaged by ischemic injury and detected various phospholipids that showed unique distributions between normal and damaged areas of the brain. ...

Huihui Liu; Rui Chen; Jiyun Wang; Suming Chen; Caiqiao Xiong; Jianing Wang; Jian Hou; Qing He; Ning Zhang; Zongxiu Nie; Lanqun Mao

2014-09-23T23:59:59.000Z

218

SAMPLING AND MASS SPECTROMETRY APPROACHES FOR THE DETECTION OF DRUGS AND FOREIGN CONTAMINANTS IN BREATH FOR HOMELAND SECURITY APPLICATIONS  

SciTech Connect

Homeland security relies heavily on analytical chemistry to identify suspicious materials and persons. Traditionally this role has focused on attribution, determining the type and origin of an explosive, for example. But as technology advances, analytical chemistry can and will play an important role in the prevention and preemption of terrorist attacks. More sensitive and selective detection techniques can allow suspicious materials and persons to be identified even before a final destructive product is made. The work presented herein focuses on the use of commercial and novel detection techniques for application to the prevention of terrorist activities. Although drugs are not commonly thought of when discussing terrorism, narcoterrorism has become a significant threat in the 21st century. The role of the drug trade in the funding of terrorist groups is prevalent; thus, reducing the trafficking of illegal drugs can play a role in the prevention of terrorism by cutting off much needed funding. To do so, sensitive, specific, and robust analytical equipment is needed to quickly identify a suspected drug sample no matter what matrix it is in. Single Particle Aerosol Mass Spectrometry (SPAMS) is a novel technique that has previously been applied to biological and chemical detection. The current work applies SPAMS to drug analysis, identifying the active ingredients in single component, multi-component, and multi-tablet drug samples in a relatively non-destructive manner. In order to do so, a sampling apparatus was created to allow particle generation from drug tablets with on-line introduction to the SPAMS instrument. Rules trees were developed to automate the identification of drug samples on a single particle basis. A novel analytical scheme was also developed to identify suspect individuals based on chemical signatures in human breath. Human breath was sampled using an RTube{trademark} and the trace volatile organic compounds (VOCs) were preconcentrated using solid phase microextraction (SPME) and identified using gas chromatography - mass spectrometry (GC-MS). Modifications to the sampling apparatus allowed for increased VOC collection efficiency, and reduced the time of sampling and analysis by over 25%. The VOCs are present in breath due to either endogenous production, or exposure to an external source through absorption, inhalation, or ingestion. Detection of these exogenous chemicals can provide information on the prior location and activities of the subject. Breath samples collected before and after exposure in a hardware store and nail salon were analyzed to investigate the prior location of a subject; breath samples collected before and after oral exposure to terpenes and terpenoid compounds, pseudoephedrine, and inhalation exposure to hexamine and other explosive related compounds were analyzed to investigate the prior activity of a subject. The elimination of such compounds from the body was also monitored. In application, this technique may provide an early warning system to identify persons of interest in the prevention and preemption stages of homeland security.

Martin, A N

2009-01-27T23:59:59.000Z

219

Accurate and Precise Determination of Boron Isotopic Ratios at Low Concentration by Positive Thermal Ionization Mass Spectrometry Using Static Multicollection of Cs2BO2+ Ions  

Science Journals Connector (OSTI)

Accurate and Precise Determination of Boron Isotopic Ratios at Low Concentration by Positive Thermal Ionization Mass Spectrometry Using Static Multicollection of Cs2BO2+ Ions ... (1) A relatively large mass difference (10%) between the two isotopes and high volatility results in significant boron isotopic variation from ?70‰(2) to +75‰(3) in natural materials; thus, boron isotopes have numerous applications in geochemistry, isotope hydrology, oceanography, environmental sciences, cosmology, and nuclear technology. ... (2) Our method provided better long-term stability of NIST 951 standard compared to “Zoom Quad” mode when more than two isotopes were determined in addition to boron isotope. ...

Mao-yong He; Ying-kai Xiao; Zhang-dong Jin; Yun-qi Ma; Jun Xiao; Yan-ling Zhang; Chong-guang Luo; Fei Zhang

2013-05-29T23:59:59.000Z

220

Mass spectrometry in biomarker applications: from untargeted discovery to targeted verification, and implications for platform convergence and clinical application  

SciTech Connect

It is really only in the last ten years that mass spectrometry (MS) has had a truly significant (but still small) impact on biomedical research. Much of this impact can be attributed to proteomics and its more basic applications. Early biomedical applications have included a number of efforts aimed at developing new biomarkers; however, the success of these endeavors to date have been quite modest - essentially confined to preclinical applications - and have often suffered from combinations of immature technology and hubris. Now that MS-based proteomics is reaching adolescence, it is appropriate to ask if and when biomarker-related applications will extend to the clinical realm, and what developments will be essential for this transition. Biomarker development can be described as a multistage process consisting of discovery, qualification, verification, research assay optimization, validation, and commercialization (1). From a MS perspective, it is possible to 'bin' measurements into 1 of 2 categories - those aimed at discovering potential protein biomarkers and those seeking to verify and validate biomarkers. Approaches in both categories generally involve digesting proteins (e.g., with trypsin) as a first step to yield peptides that can be effectively detected and identified with MS. Discovery-based approaches use broad 'unbiased' or 'undirected' measurements that attempt to cover as many proteins as possible in the hope of revealing promising biomarker candidates. A key challenge with this approach stems from the extremely large dynamic range (i.e., relative stoichiometry) of proteins of potential interest in biofluids such as plasma and the expectation that biomarker proteins of the greatest clinical value for many diseases may very well be present at low relative abundances (2). Protein concentrations in plasma extend from approximately 10{sup 10} pg/mL for albumin to approximately 10 pg/mL and below for interleukins and other cytokines.

Smith, Richard D.

2012-03-01T23:59:59.000Z

Note: This page contains sample records for the topic "accelerator mass spectrometry" from the National Library of EnergyBeta (NLEBeta).
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221

18O-Labeled Proteome Reference as Global Internal Standards for Targeted Quantification by Selected Reaction Monitoring-Mass Spectrometry  

SciTech Connect

Selected reaction monitoring-mass spectrometry (SRM-MS) is an emerging technology for high throughput targeted protein quantification and verification in biological and biomarker discovery studies; however, the cost associated with the use of stable isotope labeled synthetic peptides as internal standards is prohibitive for quantitatively screening large numbers of candidate proteins as often required in the pre-verification phase of biomarker discovery. Herein we present the proof-of-concept experiments of using an 18O-labeled 'universal' reference as comprehensive internal standards for quantitative SRM-MS analysis. With an 18O-labeled whole proteome sample as reference, every peptide of interest will have its own corresponding heavy isotope labeled internal standard, thus providing an ideal approach for quantitative screening of a large number of candidates using SRM-MS. Our results showed that the 18O incorporation efficiency using a recently improved protocol was >99.5% for most peptides investigated, a level comparable to 13C/15N labeled synthetic peptides in terms of heavy isotope incorporation. The accuracy, reproducibility, and linear dynamic range of quantification were further assessed based on known ratios of standard proteins spiked into mouse plasma with an 18O-labeled mouse plasma reference. A dynamic range of four orders of magnitude in relative concentration was obtained with high reproducibility (i.e., coefficient of variance <10%) based on the 16O/18O peak area ratios. Absolute and relative quantification of C-reactive protein and prostate-specific antigen were demonstrated by coupling an 18O-labeled reference with standard additions of protein standards. Collectively, our results demonstrated that the use of 18O-labeled reference provides a convenient and effective strategy for quantitative SRM screening of large number of candidate proteins.

Kim, Jong Seo; Fillmore, Thomas L.; Liu, Tao; Robinson, Errol W.; Hossain, Mahmud; Champion, Boyd L.; Moore, Ronald J.; Camp, David G.; Smith, Richard D.; Qian, Weijun

2011-10-11T23:59:59.000Z

222

Periostin, discovered by nano-flow liquid chromatography and mass spectrometry, is a novel marker of diabetic retinopathy  

SciTech Connect

Research highlights: {yields} In proliferative membrane and epiretinal membrane specimens, the numbers of proteins are 225 and 154, respectively, and 123 proteins are common to both. {yields} Periostin and thrombospondin-1 proteins are unique to the proliferative membrane specimens. {yields} The expression of periostin is significantly up-regulated in proliferative membrane specimens. -- Abstract: Diabetes can lead to serious microvascular complications including proliferative diabetic retinopathy (PDR), the leading cause of blindness in adults. Recent studies using gene array technology have attempted to apply a hypothesis-generating approach to elucidate the pathogenesis of PDR, but these studies rely on mRNA differences, which may or may not be related to significant biological processes. To better understand the basic mechanisms of PDR and to identify potential new biomarkers, we performed shotgun liquid chromatography (LC)/tandem mass spectrometry (MS/MS) analysis on pooled protein extracts from neovascular membranes obtained from PDR specimens and compared the results with those from non-vascular epiretinal membrane (ERM) specimens. We detected 226 distinct proteins in neovascular membranes and 154 in ERM. Among these proteins, 102 were specific to neovascular membranes and 30 were specific to ERM. We identified a candidate marker, periostin, as well as several known PDR markers such as pigment epithelium-derived factor (PEDF). We then performed RT-PCR using these markers. The expression of periostin was significantly up-regulated in proliferative membrane specimens. Periostin induces cell attachment and spreading and plays a role in cell adhesion. Proteomic analysis by LC/MS/MS, which permits accurate quantitative comparison, was useful in identifying new candidates such as periostin potentially involved in the pathogenesis of PDR.

Takada, Michiya [Division of Diabetes, Metabolism and Endocrinology, Department of Internal Medicine, Showa University School of Medicine, Tokyo (Japan)] [Division of Diabetes, Metabolism and Endocrinology, Department of Internal Medicine, Showa University School of Medicine, Tokyo (Japan); Ban, Yoshiyuki, E-mail: yshyban@yahoo.co.jp [Division of Diabetes, Metabolism and Endocrinology, Department of Internal Medicine, Showa University School of Medicine, Tokyo (Japan)] [Division of Diabetes, Metabolism and Endocrinology, Department of Internal Medicine, Showa University School of Medicine, Tokyo (Japan); Yamamoto, Gou [Department of Oral Pathology and Diagnosis, School of Dentistry, Showa University, Tokyo (Japan)] [Department of Oral Pathology and Diagnosis, School of Dentistry, Showa University, Tokyo (Japan); Ueda, Toshihiko; Saito, Yuta; Nishimura, Eiichi; Fujisawa, Kunimi; Koide, Ryohei [Department of Ophthalmology, Showa University School of Medicine, Tokyo (Japan)] [Department of Ophthalmology, Showa University School of Medicine, Tokyo (Japan); Mizutani, Masakazu; Kozawa, Tadahiko; Shiraishi, Yuji [Kozawa Eye Hospital and Diabetes Center, Ibaraki-ken (Japan)] [Kozawa Eye Hospital and Diabetes Center, Ibaraki-ken (Japan); Bando, Yasuhiko [Biosys Technologies, Inc., Meguro, Tokyo (Japan)] [Biosys Technologies, Inc., Meguro, Tokyo (Japan); Tachikawa, Tetsuhiko [Department of Oral Pathology and Diagnosis, School of Dentistry, Showa University, Tokyo (Japan)] [Department of Oral Pathology and Diagnosis, School of Dentistry, Showa University, Tokyo (Japan); Hirano, Tsutomu [Division of Diabetes, Metabolism and Endocrinology, Department of Internal Medicine, Showa University School of Medicine, Tokyo (Japan)] [Division of Diabetes, Metabolism and Endocrinology, Department of Internal Medicine, Showa University School of Medicine, Tokyo (Japan)

2010-08-20T23:59:59.000Z

223

E-Print Network 3.0 - accelerator mass spectrometer Sample Search...  

NLE Websites -- All DOE Office Websites (Extended Search)

for environmental research Mass ... Source: Pacific Northwest National Laboratory, Building Systems Program Collection: Energy Storage, Conversion and Utilization 4...

224

Heat and mass transfer in a visco–elastic fluid flow over an accelerating surface with heat source/sink and viscous dissipation  

Science Journals Connector (OSTI)

...?In this paper we present a mathematical analysis of heat and mass transfer phenomena in a visco–elastic fluid flow over an accelerating stretching sheet in the presence of heat source/sink, viscous dissipatio...

R. M. Sonth; S. K. Khan; M. S. Abel; K. V. Prasad

2002-02-01T23:59:59.000Z

225

A method for measuring methane oxidation rates using low levels of 14C-labeled methane and accelerator mass spectrometry  

E-Print Network (OSTI)

36(2):237-246. Moran, J. J. , Beal, E. J. , Vrentas, J. M. ,10.1073/ pnas.0702643105]. Beal, E. J. , C. H. House, and V.instead of sulfate (e.g. , Beal et al. 2009; Caldwell et al.

2011-01-01T23:59:59.000Z

226

Imaging with Mass Spectrometry: A SIMS and VUV-Photoionization Study of Ion-Sputtered Atoms and Clusters from GaAs and Au  

SciTech Connect

A new mass spectrometry surface imaging method is presented in which ion-sputtered neutrals are postionized by wavelength-tunable vacuum ultraviolet (VUV) light from a synchrotron source. Mass spectra and signal counts of the photoionized neutrals from GaAs (100) and Au are compared to those of the secondary ions. While clusters larger than dimers are more efficiently detected as secondary ions, certain species, such as As2, Au and Au2, are more efficiently detected through the neutral channel. Continuously tuning the photon wavelength allows photoionization efficiency (PIE) curves to be obtained for sputtered Asm (m=1,2) and Aun (n=1-4). From the observed ionization thresholds, sputtered neutral As and Au show no clear evidence of electronic excitation, while neutral clusters have photoionization onsets shifted to lower energies by ~;;0.3 eV. These shifts are attributed to unresolved vibrational and rotational excitations. High-spatial resolution chemical imaging with synchrotron VUV postionization is demonstrated at two different photon energies using a copper TEM grid embedded in indium. The resulting images are used to illustrate the use of tunable VUV light for verifying mass peak assignments by exploiting the unique wavelength-dependent PIE of each sputtered neutral species. This capability is valuable for identifying compounds when imaging chemically complex systems with mass spectrometry-based techniques.

Takahashi, Lynelle; Zhou, Jia; Wilson, Kevin R.; Leone, Stephen R.; Ahmed, Musahid

2008-12-05T23:59:59.000Z

227

Using SELDI-TOF Mass Spectrometry on Amniotic Fluid and for Clinical Proteomics and Theranostics in Disorders of Pregnancy  

Science Journals Connector (OSTI)

Clinical proteomics encompasses a multitude of experimental approaches, tools, and techniques based on proteomics technology which are directly aimed to accelerate and improve diagnosis and treatment of human ...

Irina A. Buhimschi

2012-01-01T23:59:59.000Z

228

E-Print Network 3.0 - absorption spectrometry etaas Sample Search...  

NLE Websites -- All DOE Office Websites (Extended Search)

With Confirmation of Accuracy by Inductively Coupled Plasma Mass Spectrometry and Atomic Absorption Spectrometry... -LEAFS uses absorption; graphite furnace; inductively...

229

Combined Atomic Force Microscope-Based Topographical Imaging and Nanometer Scale Resolved Proximal Probe Thermal Desorption/Electrospray Ionization-Mass Spectrometry  

SciTech Connect

Nanometer scale proximal probe thermal desorption/electrospray ionization mass spectrometry (TD/ESI-MS) was demonstrated for molecular surface sampling of caffeine from a thin film using a 30 nm diameter nano-thermal analysis (nano-TA) probe tip in an atomic force microscope (AFM) coupled via a vapor transfer line and ESI interface to a MS detection platform. Using a probe temperature of 350 C and a spot sampling time of 30 s, conical desorption craters 250 nm in diameter and 100 nm deep were created as shown through subsequent topographical imaging of the surface within the same system. Automated sampling of a 5 x 2 array of spots, with 2 m spacing between spots, and real time selective detection of the desorbed caffeine using tandem mass spectrometry was also demonstrated. Estimated from the crater volume (~2x106 nm3), only about 10 amol (2 fg) of caffeine was liberated from each thermal desorption crater in the thin film. These results illustrate a relatively simple experimental setup and means to acquire in automated fashion sub-micrometer scale spatial sampling resolution and mass spectral detection of materials amenable to TD. The ability to achieve MS-based chemical imaging with 250 nm scale spatial resolution with this system is anticipated.

Ovchinnikova, Olga S [ORNL; Nikiforov, Maxim [ORNL; Bradshaw, James A [ORNL; Jesse, Stephen [ORNL; Van Berkel, Gary J [ORNL

2011-01-01T23:59:59.000Z

230

New approaches for the chemical and physical characterization of aerosols using a single particle mass spectrometry based technique  

E-Print Network (OSTI)

1-2% of the oil mass, however the calcium ion peak at m/z 40and elemental carbon (EC) peaks. The HDDV oil mass spectraoil mass spectra were characterized by an intense Ca + ion peak and

Spencer, Matthew Todd

2007-01-01T23:59:59.000Z

231

Real-Time, On-Line Characterization of Diesel Generator Air Toxic Emissions by Resonance-Enhanced Multiphoton Ionization Time-of-Flight Mass Spectrometry  

Science Journals Connector (OSTI)

Real-Time, On-Line Characterization of Diesel Generator Air Toxic Emissions by Resonance-Enhanced Multiphoton Ionization Time-of-Flight Mass Spectrometry ... For the same reasons, the far more abundant exhaust gases such as nitrogen, water, and carbon dioxide cannot be ionized and, therefore, do not interfere with the potential detection of low (2?100 pptv) concentrations of organic molecules. ... The sample was introduced into the ionization chamber (Figure 1) through a modified pulsed valve (General Valve Series 99) that delivers 150-?s sample pulses at atmospheric back pressure through a 0.5-mm orifice at a repetition rate of 10 Hz. ...

Lukas Oudejans; Abderrahmane Touati; Brian K. Gullett

2004-03-24T23:59:59.000Z

232

Towards secondary ion mass spectrometry on the helium ion microscope: An experimental and simulation based feasibility study with He{sup +} and Ne{sup +} bombardment  

SciTech Connect

The combination of the high-brightness He{sup +}/Ne{sup +} atomic level ion source with secondary ion mass spectrometry detection capabilities opens up the prospect of obtaining chemical information with high lateral resolution and high sensitivity on the Zeiss ORION helium ion microscope. The analytical performance in terms of sputtering yield, useful yield, and detection limit is studied and subsequently optimized by oxygen and cesium flooding. Detection limits down to 10{sup -6} and 10{sup -5} can be obtained for silicon using Ne{sup +} and He{sup +}, respectively. A simulation based study reveals furthermore that a lateral resolution <10 nm can be obtained.

Wirtz, T.; Vanhove, N.; Pillatsch, L.; Dowsett, D. [Department of Science and Analysis of Materials (SAM), Centre de Recherche Public - Gabriel Lippmann, 41 rue du Brill, L-4422 Belvaux (Luxembourg); Sijbrandij, S.; Notte, J. [Carl Zeiss NTS LLC, One Corporation Way, Peabody, Massachusetts 01960 (United States)

2012-07-23T23:59:59.000Z

233

Real-Time Quantitative Analysis of Combustion-Generated Polycyclic Aromatic Hydrocarbons by Resonance-Enhanced Multiphoton Ionization Time-of-Flight Mass Spectrometry  

Science Journals Connector (OSTI)

Real-Time Quantitative Analysis of Combustion-Generated Polycyclic Aromatic Hydrocarbons by Resonance-Enhanced Multiphoton Ionization Time-of-Flight Mass Spectrometry ... Field data1 suggest that naphthalene, fluorene, and anthracene are among the most abundant PAH products of incomplete hydrocarbon production. ... The sample transfer line is 6.35 mm diameter, quartz-lined stainless steel tubing (Alltech, Deerfield, IL) that is heated to 250?300 °C using flexible cable heaters (Omega Engineering, Stamford, CT). Care is taken to uniformly heat the sample transfer line, since the efficiency of the line is reduced dramatically by the presence of cold spots. ...

Christopher M. Gittins; Marco J. Castaldi; Selim M. Senkan; Eric A. Rohlfing

1997-02-01T23:59:59.000Z

234

Comprehensive two-dimensional gas chromatography coupled to time-of-flight mass spectrometry of coal liquids produced during a coal liquefaction process  

SciTech Connect

Comprehensive two-dimensional gas chromatography (GC) coupled to time-of-flight mass spectrometry (MS) has been applied to the analysis of coal-derived liquids from the former British Coal Point-of-Ayr coal liquefaction plant. The feed to the hydrocracker and the resulting product were analyzed. The results refer almost exclusively to the plant-derived recycle solvent, known as the liquefaction solvent; the molecular mass range of the GC does not exceed that of the solvent. The method allows for the resolution of the numerous structural isomers of tetralin and methyl indan, one pair of hydrogen-donor (necessary for the dissolution of coal) and isomeric nondonor (that reduce the hydrogen donors) components of the recycle solvent. In addition, the n-alkanes that concentrate in the recycle solvent are easily observed in comparison with the results from one-dimensional GC-MS. 24 refs., 6 figs., 1 tab.

Jacqui F. Hamilton; Alistair. C. Lewis; Marcos Millan; Keith D. Bartle; Alan A. Herod; Rafael Kandiyoti [University of York, York (United Kingdom). Department of Chemistry

2007-01-15T23:59:59.000Z

235

Airfoil sampling of a pulsed Laval beam with tunable vacuum ultraviolet (VUV) synchrotron ionization quadrupole mass spectrometry: Application to low--temperature kinetics and product detection  

SciTech Connect

A new pulsed Laval nozzle apparatus with vacuum ultraviolet (VUV) synchrotron photoionization quadrupole mass spectrometry is constructed to study low-temperature radicalneutralchemical reactions of importance for modeling the atmosphere of Titan and the outer planets. A design for the sampling geometry of a pulsed Laval nozzle expansion has beendeveloped that operates successfully for the determination of rate coefficients by time-resolved mass spectrometry. The new concept employs airfoil sampling of the collimated expansion withexcellent sampling throughput. Time-resolved profiles of the high Mach number gas flow obtained by photoionization signals show that perturbation of the collimated expansion by theairfoil is negligible. The reaction of C2H with C2H2 is studied at 70 K as a proof-of-principle result for both low-temperature rate coefficient measurements and product identification basedon the photoionization spectrum of the reaction product versus VUV photon energy. This approach can be used to provide new insights into reaction mechanisms occurring at kinetic ratesclose to the collision-determined limit.

Soorkia, Satchin; Liu, Chen-Lin; Savee, John D.; Ferrell, Sarah J.; Leone, Stephen R.; Wilson, Kevin R.

2011-10-12T23:59:59.000Z

236

New approaches for the chemical and physical characterization of aerosols using a single particle mass spectrometry based technique  

E-Print Network (OSTI)

1-2% of the oil mass, however the calcium ion peak at m/z 40lubricating oil is characterized by a very intense Ca + peakand elemental carbon (EC) peaks. The HDDV oil mass spectra

Spencer, Matthew Todd

2007-01-01T23:59:59.000Z

237

Liquid Sampling-Atmospheric Pressure Glow Discharge (LS-APGD) Ionization Source for Elemental Mass Spectrometry: Preliminary Parametric Evaluation and Figures of Merit  

SciTech Connect

A new, low power ionization source for the elemental analysis of aqueous solutions has recently been described. The liquid sampling-atmospheric pressure glow discharge (LS-APGD) source operates at relatively low currents (<20 mA) and solution flow rates (<50 ?L min-1), yielding a relatively simple alternative for atomic mass spectrometry applications. The LS-APGD has been interfaced to what is otherwise an organic, LC-MS mass analyzer, the Thermo Scientific Exactive Orbitrap without any modifications; other than removing the electrospray ionization (ESI) source supplied with that instrument. A glow discharge is initiated between the surface of the test solution exiting a glass capillary and a metallic counter electrode mounted at a 90° angle and separated by a distance of ~5 mm. As with any plasma-based ionization source, there are key discharge operation and ion sampling parameters that affect the intensity and composition of the derived mass spectra; including signal-to-background ratios. We describe here a preliminary parametric evaluation of the roles of discharge current, solution flow rate, argon sheath gas flow rate, and ion sampling distance as they apply on this mass analyzer system. A cursive evaluation of potential matrix effects due to the presence of easily ionized elements (EIEs) indicate that sodium concentrations of up to 500 ?g mL-1 generally cause suppressions of less than 50%, dependant upon the analyte species. Based on the results of this series of studies, preliminary limits of detection (LOD) have been established through the generation of calibration functions. Whilst solution-based concentrations LOD levels of 0.02 – 2 ?g mL-1 3 are not impressive on the surface, the fact that they are determined via discrete 5 ?L injections leads to mass-based detection limits at picogram to singlenanogram levels. The overhead costs associated with source operation (10 W d.c. power, solution flow rates of <50 ?L min-1, and gas flow rates <10 mL min-1) are very attractive. While further optimization in the source design is suggested here, it is believed that the LS-APGD ion source may present a practical alternative to inductively-coupled plasma (ICP) sources typically employed in elemental mass spectrometry.

Quarles, C. Derrick; Carado, Anthony J.; Barinaga, Charles J.; Koppenaal, David W.; Marcus, R. Kenneth

2012-01-01T23:59:59.000Z

238

Thermal Decomposition of Molecules Relevant to Combustion and Chemical Vapor Deposition by Flash Pyrolysis Time-of-Flight Mass Spectrometry  

E-Print Network (OSTI)

of Small Molecules by Flash Pyrolysis, University ofwas performed using flash pyrolysis vacuum-ultraviolet time-Vapor Deposition by Flash Pyrolysis Time-of-Flight Mass

Lemieux, Jessy Mario

2013-01-01T23:59:59.000Z

239

Automated probe microdistillation/mass spectrometry for the analysis of high-molecular weight compounds in fossil fuels  

SciTech Connect

Automated probe microdistillation/mass spectroscopy is described. The application of computer hardware and the development of computer software eliminate the dilatory nature of acquiring both the temperature and associated mass spectra and reduces the acquired data for processing. The interaction of various hardware components of the system as well as the associated software is described. (DMC)

Scheppele, S.E.; Grindstaff, Q.G.; Grigsby, R.D.; Chung, K.C.; Hwang, C.S.; Marriott, T.D.; Schronk, L.R.

1982-08-01T23:59:59.000Z

240

C-O-H ratios of silicate melt inclusions in basalts from the Galapagos spreading center near 95 degree W: A leaser decrepitation mass spectrometry study  

SciTech Connect

Volatile ratios (primarily of H{sub 2}O and CO{sub 2}) in individual silicate melt (glass) inclusions in minerals have been analyzed using laser volatilization and mass spectrometry. A Nd-glass laser was used to produce 50-micrometer diameter pits in silicate melt inclusions. Released volatiles were analyzed directly with a computer-controlled quadrupole mass spectrometer. The mean CO{sub 2}/H{sub 2}O from the propagating rift (0.245 {plus minus} 0.068) silicate glass inclusions is significantly lower than that of the actively failing rift (0.641 {plus minus} 0.241); this difference probably reflects different degrees of degassing during contrasting magmatic histories for the two regions. Relatively undifferentiated failing rift magmas must have relatively short crustal residence time prior to eruption and, therefore, have not undergone significant degassing of CO{sub 2}, as would appear to be the case for the more highly fractionated propagating rift magmas. The laser-mass spectrometric system described herein has the ability to act as a point-source probing device that can differentiate between the various volatile sites in minerals and rocks (as well as synthetic materials) on a micrometer scale.

Yonover, R.N.; Sinton, J.M. (Univ. of Hawaii, Honolulu (USA)); Gibson, E.K. (NASA/Johnson Space Center, Houston, TX (USA)); Sommer, M.A.

1989-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "accelerator mass spectrometry" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Isotope pattern deconvolution for peptide mass spectrometry by non-negative least squares/least absolute deviation template matching  

Science Journals Connector (OSTI)

Identification of overlapping isotope patterns in mass spectrometric data is achieved using non-negative least squares/non-negative least absolute deviation regression, and is able to disentangle complicated overlaps of patterns.

Martin Slawski; Rene Hussong; Andreas Tholey; Thomas Jakoby; Barbara Gregorius; Andreas Hildebrandt; Matthias Hein

2012-11-08T23:59:59.000Z

242

Atmospheric-Pressure Argon Surface-Wave Plasma (SWP) as an Ion Source in Elemental Mass Spectrometry  

Science Journals Connector (OSTI)

Results of the study of a high-power argon surface-wave plasma as an ion source for mass spectrometric elemental analysis of aqueous solutions are presented. The plasma is operated...

Boudreau, D; Hubert, J

1993-01-01T23:59:59.000Z

243

Advanced Mass Calibration and Visualization for FT-ICR Mass Spectromet...  

NLE Websites -- All DOE Office Websites (Extended Search)

for FT-ICR Mass Spectrometry Imaging. Abstract: Mass spectrometry imaging by Fourier transform ion cyclotron resonance (FT-ICR) yields hundreds of unique peaks, many of which...

244

Accelerator System Development at High Voltage Engineering  

SciTech Connect

Throughout the years, HVE has continuously extended the capabilities of its accelerator systems to meet the rising demands from a diverse field of applications, among which are deep level ion implantation, micro-machining, neutron production for biomedical research, isotope production or accelerator mass spectrometry. Characteristic for HVE accelerators is the coaxial construction of the all solid state power supply around the acceleration tubes. With the use of solid state technology, the accelerators feature high stability and very low ripple. Terminal voltages range from 1 to 6 MV for HVE Singletrons and Tandetrons. The high-current versions of these accelerators can provide ion beams with powers of several kW. In the last years, several systems have been built with terminal voltages of 1.25 MV, 2 MV and 5 MV. Recently, the first system based on a 6 MV Tandetron has passed the factory tests. In this paper we describe the characteristics of the HVE accelerator systems and present as example recent systems.

Klein, M. G.; Gottdang, A.; Haitsma, R. G.; Mous, D. J. W. [High Voltage Engineering Europa B.V., P.O. Box 99, Amersfoort 3800 AB (Netherlands)

2009-03-10T23:59:59.000Z

245

High Sensitivity SIMS Using DC Accelerators  

Science Journals Connector (OSTI)

Experiments have been conducted which show that secondary ion mass spectrometry (SIMS), together with the addition of a...

K. H. Purser

1979-01-01T23:59:59.000Z

246

Poly(3,4-ethylenedioxypyrrole) Modified Emitter Electrode for Substitution of Homogeneous Redox Buffer Agent Hydroquinone in Electrospray Ionization Mass Spectrometry  

SciTech Connect

The electrolysis inherent to the operation of the electrospray ionization (ESI) source used with mass spectrometry (MS) is a well-known attendant effect of generating unipolar spray droplets and may affect the analysis of the analyte of interest. Undesirable electrolysis of an analyte may be prevented by limiting the emitter electrode current and/or the mass transport characteristics of the system. However, these ways to avoid analyte electrolysis may not be applcable in all ESI-MS experiments. For example, in the case of specific nanospray systems (e.g. the wire-in-a-capillary bulk-loaded or chip-based tip-loaded nanospray configurations), the solution flow rate is fixed in the 50-500 nL/min range and the electrode surface to volume ratio is large presenting a very effcient analyte to electrode mass transport configuration. In these situations, control over the interfacial potential of the working electrode via homogeneous or traditional heterogeneous (sacrificial metal) redox buffering is a possible way to prevent analyte electrolysis. However, byproducts of these redox buffering approaches can appear in the mass spectra and/or they can chemically alter the analyte. For example, the main reason for using hydroquinone as a homogeneous redox buffer, in addition to its relatively low oxidation potential, is that neither the original compound nor its oxidation product benzoquinone can be detected directly by ESI-MS. However, benzoquinone can alter analytes with thiol functional groups by reacting with those groups via a 1,4-Michael addition.

Peintler-Krivan, Emese [ORNL; Van Berkel, Gary J [ORNL; Kertesz, Vilmos [ORNL

2010-01-01T23:59:59.000Z

247

Accurate-Mass Databases for Comprehensive Screening of Pesticide Residues in Food by Fast Liquid Chromatography Time-of-Flight Mass Spectrometry  

Science Journals Connector (OSTI)

The use of agrochemicals at various stages of cultivation has an important impact in food protection and quality preservation. ... The chromatographic method held the initial mobile phase composition (10% B) constant for 1 min, followed by a linear gradient to 100% B up to 12 min, and kept for 5 min at 100% B. The flow rate used was 0.6 mL min?1. ... Accurate-Mass Database of the Studied Pesticides Including Retention Times (RT), Theoretical Accurate Masses, and Elemental Compositions of the Detected Ions ...

Milagros Mezcua; Octavio Malato; Juan F. García-Reyes; Antonio Molina-Díaz; Amadeo R. Fernández-Alba

2008-12-31T23:59:59.000Z

248

Direct determination of the adiabatic ionization energy of NO2 as measured by guided ion-beam mass spectrometry  

E-Print Network (OSTI)

Direct determination of the adiabatic ionization energy of NO2 as measured by guided ion-beam mass the past 60 years the value for the ionization energy (IE) of nitrogen dioxide has been measured many times, Utah 84112 (Received 16 April 1992; accepted 4 May 1992) The adiabatic ionization energy (IE) of NOa

Clemmer, David E.

249

Analysis on the Go: Quantitation of Drugs of Abuse in Dried Urine with Digital Microfluidics and Miniature Mass Spectrometry  

E-Print Network (OSTI)

Analysis on the Go: Quantitation of Drugs of Abuse in Dried Urine with Digital Microfluidics the development of a method coupling microfluidics and a miniature mass spectrometer, applied to quantitation of drugs of abuse in urine. A custom digital microfluidic system was designed to deliver droplets

Zandstra, Peter W.

250

Simultaneous Determination of 16 Pyrethroid Residues in Tea Samples Using Gas Chromatography and Ion Trap Mass Spectrometry  

Science Journals Connector (OSTI)

......67-64-1 Acetone | Acetone Gas Chromatography-Mass...are widely used in tea production, and pesticide residues...Analysis was performed by gas chromatography with ion...chroma- tography (LC), gas chromatography (GC...sensitive, and low- cost detection for pyrethroids......

Kuang Hua; Miao Hong; Hou Xiaolin; Zhao Yunfeng; Wu Yongning; Xu Chuanlai

2010-10-01T23:59:59.000Z

251

Applications of High-Resolution Electrospray Ionization Mass Spectrometry to Measurements of Average Oxygen to Carbon Ratios in Secondary Organic Aerosols  

SciTech Connect

The applicability of high resolution electrospray ionization mass spectrometry (HR ESI-MS) to measurements of the average oxygen to carbon ratio (O/C) in organic aerosols was investigated. Solutions with known average O/C containing up to 10 standard compounds representative of secondary organic aerosol (SOA) were analyzed and corresponding electrospray ionization efficiencies were quantified. The assumption of equal ionization efficiency commonly used in estimating O/C ratios of organic aerosols was found to be reasonably accurate. We found that the accuracy of the measured O/C ratios increases by averaging the values obtained from both (+) and (-) modes. A correlation was found between the ratio of the ionization efficiencies in the positive and negative ESI modes with the octanol-water partition constant, and more importantly, with the compound's O/C. To demonstrate the utility of this correlation for estimating average O/C values of unknown mixtures, we analyzed the ESI (+) and ESI (-) data for SOA produced by oxidation of limonene and isoprene and compared to online O/C measurements using an aerosol mass spectrometer (AMS). This work demonstrates that the accuracy of the HR ESI-MS methods is comparable to that of the AMS, with the added benefit of molecular identification of the aerosol constituents.

Bateman, Adam P.; Laskin, Julia; Laskin, Alexander; Nizkorodov, Sergey

2012-07-02T23:59:59.000Z

252

Standard test method for analysis of urine for uranium-235 and uranium-238 isotopes by inductively coupled plasma-mass spectrometry  

E-Print Network (OSTI)

1.1 This test method covers the determination of the concentration of uranium-235 and uranium-238 in urine using Inductively Coupled Plasma-Mass Spectrometry. This test method can be used to support uranium facility bioassay programs. 1.2 This method detection limits for 235U and 238U are 6 ng/L. To meet the requirements of ANSI N13.30, the minimum detectable activity (MDA) of each radionuclide measured must be at least 0.1 pCi/L (0.0037 Bq/L). The MDA translates to 47 ng/L for 235U and 300 ng/L for 238U. Uranium– 234 cannot be determined at the MDA with this test method because of its low mass concentration level equivalent to 0.1 pCi/L. 1.3 The digestion and anion separation of urine may not be necessary when uranium concentrations of more than 100 ng/L are present. 1.4 Units—The values stated in picoCurie per liter units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard. 1....

American Society for Testing and Materials. Philadelphia

2010-01-01T23:59:59.000Z

253

Mass Spectrometer: Orbitrap | EMSL  

NLE Websites -- All DOE Office Websites (Extended Search)

Software (ISIS): A Machine Learning Approach to Tandem Mass Spectral Identification of Lipids. Liquid chromatography-mass spectrometry-based metabolomics has gained importance...

254

Standard test method for isotopic analysis of hydrolyzed uranium hexafluoride and uranyl nitrate solutions by thermal ionization mass spectrometry  

E-Print Network (OSTI)

1.1 This method applies to the determination of isotopic composition in hydrolyzed nuclear grade uranium hexafluoride. It covers isotopic abundance of 235U between 0.1 and 5.0 % mass fraction, abundance of 234U between 0.0055 and 0.05 % mass fraction, and abundance of 236U between 0.0003 and 0.5 % mass fraction. This test method may be applicable to other isotopic abundance providing that corresponding standards are available. 1.2 This test method can apply to uranyl nitrate solutions. This can be achieved either by transforming the uranyl nitrate solution to a uranyl fluoride solution prior to the deposition on the filaments or directly by depositing the uranyl nitrate solution on the filaments. In the latter case, a calibration with uranyl nitrate standards must be performed. 1.3 This test method can also apply to other nuclear grade matrices (for example, uranium oxides) by providing a chemical transformation to uranyl fluoride or uranyl nitrate solution. 1.4 This standard does not purport to address al...

American Society for Testing and Materials. Philadelphia

2005-01-01T23:59:59.000Z

255

Solid-state Marx based two-switch voltage modulator for the On-Line Isotope Mass Separator accelerator at the European Organization for Nuclear Research  

SciTech Connect

A new circuit topology is proposed to replace the actual pulse transformer and thyratron based resonant modulator that supplies the 60 kV target potential for the ion acceleration of the On-Line Isotope Mass Separator accelerator, the stability of which is critical for the mass resolution downstream separator, at the European Organization for Nuclear Research. The improved modulator uses two solid-state switches working together, each one based on the Marx generator concept, operating as series and parallel switches, reducing the stress on the series stacked semiconductors, and also as auxiliary pulse generator in order to fulfill the target requirements. Preliminary results of a 10 kV prototype, using 1200 V insulated gate bipolar transistors and capacitors in the solid-state Marx circuits, ten stages each, with an electrical equivalent circuit of the target, are presented, demonstrating both the improved voltage stability and pulse flexibility potential wanted for this new modulator.

Redondo, L. M.; Canacsinh, H.; Ferrao, N.; Mendes, C. [Instituto Superior de Engenharia de Lisboa (ISEL), R. Conselheiro Emidio Navarro 1, Lisbon 1959-007 (Portugal); Nuclear Physics Center-Lisbon University (CFNUL), Av. Prof. Gama Pinto 2, Lisbon 1649-003 (Portugal); Silva, J. Fernando [Instituto Superior Tecnico (IST), Universidade Tecnica de Lisboa, Av. Rovisco Pais 1, Lisbon 1049-001 (Portugal); Center for Innovation in Electrical and Energy Engineering-TU Lisbon, Av. Rovisco Pais 1, Lisbon 1049-001 (Portugal); Soares, R. [Nuclear Physics Center--Lisbon University (CFNUL), Av. Prof. Gama Pinto 2, Lisbon 1649-003 (Portugal); ABT Group, TE Department, Site de Prevessin, FR-01631 CERN (Switzerland); Schipper, J.; Fowler, A. [ABT Group, TE Department, Site de Prevessin, FR-01631 CERN (Switzerland)

2010-07-15T23:59:59.000Z

256

Confirmatory analysis of ethylglucuronide in urine by liquid-chromatography/electrospray ionization/tandem mass spectrometry according to forensic guidelines  

Science Journals Connector (OSTI)

?-D-ethylglucuronide (EtG) is a stable Phase II metabolite of ethanol which can be detected in urine samples several days after elimination of ethanol. It is a useful diagnostic parameter for monitoring abstinence of alcoholics in alcohol withdrawal treatment. For this purpose, determination in urine is mainly performed by LC-MS, LC-MS/MS, or by GC-MS. For the mass spectrometric identification and detection of controlled substances in more sensitive fields such as forensic toxicology, workplace drug testing, doping analysis, and veterinary organic residue control, official guidelines have been released requiring a chromatographic separation and a minimum of two mass spectrometric transitions of the analyte. However, for detection of EtG none of the published LC-MS/MS methods could fulfill the minimum requirements of any of these guidelines. Therefore, an existing LC-MS/MS method has been modified by monitoring further MS/MS transitions instead of only one (deprotonated molecule [M ? H]?/product ions: m/z 75, 85, 113, and 159 optional) with the aim of withstanding administrative or court scrutiny in forensic or workplace drug testing cases. Full method validation has been performed in accordance to guidelines of the German Society of Toxicology and Forensic Chemistry (GTFCh) and requirements of ISO 17025. One application field in the United States is a workplace monitoring program to detect surreptitious alcohol use among recovering health professionals, who by contract had agreed on total abstinence after drug and alcohol withdrawal therapy.

Wolfgang Weinmann; Patrick Schaefer; Annette Thierauf; André Schreiber; Friedrich Martin Wurst

2004-01-01T23:59:59.000Z

257

Development of an on-line isotope dilution laser ablation inductively coupled plasma mass spectrometry (LA–ICP-MS) method for determination of boron in silicon wafers  

Science Journals Connector (OSTI)

A method has been developed based on an on-line isotope dilution technique couple with laser ablation/inductively coupled plasma mass spectrometry (LA–ICP-MS), for the determination of boron in p-type silicon wafers. The laser-ablated sample aerosol was mixed on-line with an enriched boron aerosol supplied continuously using a conventional nebulization system. Upon mixing the two aerosol streams, the isotope ratio of boron changed rapidly and was then recorded by the ICP-MS system for subsequent quantification based on the isotope dilution principle. As an on-line solid analysis method, this system accurately quantifies boron concentrations in silicon wafers without the need for an internal or external solid reference standard material. Using this on-line isotope dilution technique, the limit of detection for boron in silicon wafers is 2.8 × 1015 atoms cm?3. The analytical results obtained using this on-line methodology agree well with those obtained using wet chemical digestion methods for the analysis of p-type silicon wafers containing boron concentrations ranging from 1.0 × 1016 to 9.6 × 1018 atoms cm?3.

Chao-Kai Yang; Po-Hsiang Chi; Yong-Chine Lin; Yuh-Chang Sun; Mo-Hsiung Yang

2010-01-01T23:59:59.000Z

258

Simultaneous determination of nine trace mono- and di-chlorophenols in water by ion chromatography atmospheric pressure chemical ionization mass spectrometry  

Science Journals Connector (OSTI)

A novel analytical method was proposed for the rapidly simultaneous determination of nine mono-chlorophenols (MCPs) and di-chlorophenols (DCPs) in water samples using eluent generator ion chromatography (IC) coupled with an atmospheric pressure chemical ionization mass spectrometry (APCI-MS) in the negative mode. The IC separation was carried out on an IonPac® AS11 analytical column (250 mm × 4.0 mm) using gradient KOH containing 15% acetonitrile as organic modifier at a constant flow rate of 1.0 mL/min. The molecular ions m/z [M ? H]? 127 and 161 were selected for the quantification in selected ion monitoring (SIM) mode for \\{MCPs\\} and DCPs, respectively. The average recoveries were between 80.6% and 92.6%. Within-day and day-to-day relative standard deviations were less than 12.1% and 13.3%, respectively. The method allowed the nine objective compounds in water samples to be determined at ?g/L levels. It was confirmed that this method could be used in routine analysis.

Micong Jin; Yiwen Yang

2006-01-01T23:59:59.000Z

259

Identification of volatile butyl rubber thermal-oxidative degradation products by cryofocusing gas chromatography/mass spectrometry (cryo-GC/MS).  

SciTech Connect

Chemical structure and physical properties of materials, such as polymers, can be altered as aging progresses, which may result in a material that is ineffective for its envisioned intent. Butyl rubber formulations, starting material, and additives were aged under thermal-oxidative conditions for up to 413 total days at up to 124 %C2%B0C. Samples included: two formulations developed at Kansas City Plant (KCP) (%236 and %2310), one commercially available formulation (%2321), Laxness bromobutyl 2030 starting material, and two additives (polyethylene AC-617 and Vanax MBM). The low-molecular weight volatile thermal-oxidative degradation products that collected in the headspace over the samples were preconcentrated, separated, and detected using cryofocusing gas chromatography mass spectrometry (cryo-GC/MS). The majority of identified degradation species were alkanes, alkenes, alcohols, ketones, and aldehydes. Observations for Butyl %2310 aged in an oxygen-18 enriched atmosphere (18O2) were used to verify when the source of oxygen in the applicable degradation products was from the gaseous environment rather than the polymeric mixture. For comparison purposes, Butyl %2310 was also aged under non-oxidative thermal conditions using an argon atmosphere.

Smith, Jonell Nicole; White, Michael Irvin; Bernstein, Robert; Hochrein, James Michael

2013-02-01T23:59:59.000Z

260

Soluble arsenic and selenium species in fly ash/organic waste-amended soils using ion chromatography-inductively coupled plasma mass spectrometry  

SciTech Connect

Mixing coal fly ash with an organic waste increases macronutrient content and may make land application of fly ash a viable disposal alternative. However, trace element chemistry of these mixed waste products warrants investigation. Speciation of As and Se in soil solutions of fly ash-, poultry litter- and sewage sludge-amended soils was determined over a 10-day period by ion chromatography coupled to inductively coupled plasma mass spectrometry (IC-ICP-MS). Detection limits were 0.031, 0.028, 0.051, 0.161, 0.497, and 0.660 {micro}g L{sup {minus}1} for dimethylarsinate (DMA), As(III), monomethylarsonate (MMA), As(V), Se(IV), and Se(VI), respectively. Arsenic was highly water-soluble from poultry litter and appeared to be predominantly As(V). Arsenic(V) was the predominant species in soil amended with two fly ashes. Application of fly ash/poultry litter mixtures increased As solubility and led to the prevalence of DMA as the major As species. DMA concentrations of these soil solutions decreased rapidly over the sampling period relative to As(V), suggesting that DMA readily underwent mineralization in the soil solution. Se(VI) was the predominant soluble Se species in all treatments indicating rapid oxidation of Se(IV) initially solubilized from the fly ashes.

Jackson, B.P.; Miller, W.P. [Univ. of Georgia, Athens, GA (United States). Dept. of Crop and Soil Sciences] [Univ. of Georgia, Athens, GA (United States). Dept. of Crop and Soil Sciences

1999-01-15T23:59:59.000Z

Note: This page contains sample records for the topic "accelerator mass spectrometry" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Rapid determination of endogenous cytokinins in plant samples by combination of magnetic solid phase extraction with hydrophilic interaction chromatography–tandem mass spectrometry  

Science Journals Connector (OSTI)

A 2-acrylamido-2-methyl-1-propanesulfonic acid-co-ethylene glycol dimethacrylate (Fe3O4/SiO2/P(AMPS-co-EGDMA)) copolymer was prepared and used as a magnetic solid phase extraction (MSPE) medium for recovery of endogenous cytokinins (CKs) from plant extracts. This magnetic porous polymer was characterized by electron microscopy, nitrogen sorption experiments, elemental analysis and Fourier-transformed infrared spectroscopy. It was demonstrated to have high extraction capacity toward \\{CKs\\} in plants due to its specificity, surface area and porous structure. Coupled with hydrophilic interaction chromatography–tandem mass spectrometry (HILIC–MS/MS), a rapid, simple, and effective MSPE–HILIC–MS/MS analytical method for the quantitative analysis of endogenous \\{CKs\\} in Oryza sativa (O. sativa) roots was successfully established. Good linearities were obtained for all \\{CKs\\} investigated with correlation coefficients (R2) > 0.9975. The results showed that \\{LODs\\} (S/N = 3) were ranged from 0.18 to 3.65 pg mL?1. Reproducibility of the method was obtained with intra-day and inter-day relative standard deviations (RSDs) less than 16.1% and the recoveries in plant samples ranged from 72.8% to 115.5%. Finally, the MSPE–HILIC–MS/MS method was applied to several plant samples, and the amounts of endogenous \\{CKs\\} in O. sativa roots, leaves and Arabidopsis thaliana (A. thaliana) were successfully determined.

Zhao Liu; Bao-Dong Cai; Yu-Qi Feng

2012-01-01T23:59:59.000Z

262

Determination of N,N-dimethyltryptamine in beverages consumed in religious practices by headspace solid-phase microextraction followed by gas chromatography ion trap mass spectrometry  

Science Journals Connector (OSTI)

A novel analytical approach combining solid-phase microextraction (SPME)/gas chromatography ion trap mass spectrometry (GC-IT-MS) was developed for the detection and quantification N,N-dimethyltryptamine (DMT), a powerful psychoactive indole alkaloid present in a variety of South American indigenous beverages, such as ayahuasca and vinho da jurema. These particular plant products, often used within a religious context, are increasingly consumed throughout the world following an expansion of religious groups and the availability of plant material over the Internet and high street shops. The method described in the present study included the use of SPME in headspace mode combined GC-IT-MS and included the optimization of the SPME procedure using multivariate techniques. The method was performed with a polydimethylsiloxane/divinylbenzene (PDMS/DVB) fiber in headspace mode (70 min at 60 °C) which resulted in good precision (RSD9975) was also observed. In addition, the proposed method showed good robustness and allowed for the minimization of sample manipulation. Five jurema beverage samples were prepared in the laboratory in order to study the impact of temperature, pH and ethanol on the ability to extract DMT into solution. The developed method was then applied to the analysis of twelve real ayahuasca and vinho da jurema samples, obtained from Brazilian religious groups, which revealed DMT concentration levels between 0.10 and 1.81 g L?1.

Alain Gaujac; Nicola Dempster; Sandro Navickiene; Simon D. Brandt; Jailson Bittencourt de Andrade

2013-01-01T23:59:59.000Z

263

Determination of actinides in environmental and biological samples using high-performance chelation ion chromatography coupled to sector-field inductively coupled plasma mass spectrometry  

Science Journals Connector (OSTI)

High-performance chelation ion chromatography, using a neutral polystyrene substrate dynamically loaded with 0.1 mM dipicolinic acid, coupled with sector-field inductively coupled plasma mass spectrometry has been successfully used for the separation of the actinides thorium, uranium, americium, neptunium and plutonium. Using this column it was possible to separate the various actinides from each other and from a complex sample matrix. In particular, it was possible to separate plutonium and uranium to facilitate the detection of the former free of spectral interference. The column also exhibited some selectivity for different oxidation states of Np, Pu and U. Two oxidation states each for plutonium and neptunium were found, tentatively identified as Np(V) and Pu(III) eluting at the solvent front, and Np(IV) and Pu(IV) eluting much later. Detection limits were 12, 8, and 4 fg for 237Np, 239Pu, and 241Am, respectively, for a 0.5 ml injection. The system was successfully used for the determination of 239Pu in NIST 4251 Human Lung and 4353 Rocky Flats Soil, with results of 570±29 and 2939±226 fg g?1, respectively, compared with a certified range of 227–951 fg g?1 for the former and a value of 3307± 248 fg g?1 for the latter.

Jason B. Truscott; Phil Jones; Ben E. Fairman; E. Hywel Evans

2001-01-01T23:59:59.000Z

264

Chemometric optimization of dispersive suspended microextraction followed by gas chromatography–mass spectrometry for the determination of polycyclic aromatic hydrocarbons in natural waters  

Science Journals Connector (OSTI)

Abstract A dispersive suspended microextraction (DSME) method coupled with gas chromatography–mass spectrometry (GC–MS) was developed and validated for the simultaneous determination of ten polycyclic aromatic hydrocarbons in real water samples. The optimization of the method was achieved with a 27–4 Plackett–Burman design, while the significant factors were optimized using a central composite design (CCD). The parameters that were studied included the sample volume, organic solvent volume, extraction time, restoration time and organic solvent. The optimum experimental conditions for the proposed method comprised 4.3 mL of the water sample, 93 ?L of toluene as the extraction solvent, a 104-s extraction time and a 10-min restoration time. The recoveries varied from 70 to 111%. Chrysene was the least recovered compound, while anthracene displayed the highest extraction efficiency. The analytical method (DSME) was shown to be linear (R2 > 0.993) over the studied range of concentrations, exhibiting satisfactory precision (RSD% < 10.6%) and reaching limits of detection between 8 and 46 ng L?1.

Nikolaos P. Petridis; Vasilios A. Sakkas; Triantafyllos A. Albanis

2014-01-01T23:59:59.000Z

265

C60 Secondary Ion Fourier Transform Ion Cyclotron Resonance Mass...  

NLE Websites -- All DOE Office Websites (Extended Search)

C60 Secondary Ion Fourier Transform Ion Cyclotron Resonance Mass Spectrometry. C60 Secondary Ion Fourier Transform Ion Cyclotron Resonance Mass Spectrometry. Abstract: Secondary...

266

A Hybrid Approach to Protein Differential Expression in Mass...  

NLE Websites -- All DOE Office Websites (Extended Search)

Hybrid Approach to Protein Differential Expression in Mass Spectrometry-Based Proteomics. A Hybrid Approach to Protein Differential Expression in Mass Spectrometry-Based...

267

Pyrolysis Gas Chromatography Mass Spectrometry Studies to Evaluate High-Temperature Aqueous Pretreatment as a Way to Modify the Composition of Bio-Oil from Fast Pyrolysis of Wheat Straw  

Science Journals Connector (OSTI)

Pyrolysis Gas Chromatography Mass Spectrometry Studies to Evaluate High-Temperature Aqueous Pretreatment as a Way to Modify the Composition of Bio-Oil from Fast Pyrolysis of Wheat Straw ... ?-Cellulose was obtained from Sigma-Aldrich (St. Louis, Missouri). ... This evidence suggests that CHW pretreatment may produce bio-oil that is composed of a greater amount of sugars and furanics and fewer small molecules and may therefore be a viable option to modify the chemical composition of bio-oils. ...

Robert Lee Johnson; Shi-Shen Liaw; Manuel Garcia-Perez; Su Ha; Sean S.-Y. Lin; Armando G. McDonald; Shulin Chen

2009-10-07T23:59:59.000Z

268

E-Print Network 3.0 - absorption spectrometry feasibility Sample...  

NLE Websites -- All DOE Office Websites (Extended Search)

Franc&o, CA 94101&fM, USA Laser Microprobe Mass Spectrometry Summary: graphite fur- nace atomic absorption spectrometry (ETAAS) measurement of tin in sulfate matrices were......

269

Targeted Peptide Measurements in Biology and Medicine: Best Practices for Mass Spectrometry-based Assay Development Using a Fit-for-Purpose Approach  

SciTech Connect

Adoption of targeted mass spectrometry (MS) approaches such as multiple reaction monitoring (MRM) to study biological and biomedical questions is well underway in the proteomics community. Successful application depends on the ability to generate reliable assays that uniquely and confidently identify target peptides in a sample. Unfortunately, there is a wide range of criteria being applied to say that an assay has been successfully developed. There is no consensus on what criteria are acceptable and little understanding of the impact of variable criteria on the quality of the results generated. Publications describing targeted MS assays for peptides frequently do not contain sufficient information for readers to establish confidence that the tests work as intended or to be able to apply the tests described in their own labs. Guidance must be developed so that targeted MS assays with established performance can be made widely distributed and applied by many labs worldwide. To begin to address the problems and their solutions, a workshop was held at the National Institutes of Health with representatives from the multiple communities developing and employing targeted MS assays. Participants discussed the analytical goals of their experiments and the experimental evidence needed to establish that the assays they develop work as intended and are achieving the required levels of performance. Using this “fit-for-purpose” approach, the group defined three tiers of assays distinguished by their performance and extent of analytical characterization. Computational and statistical tools useful for the analysis of targeted MS results were described. Participants also detailed the information that authors need to provide in their manuscripts to enable reviewers and readers to clearly understand what procedures were performed and to evaluate the reliability of the peptide or protein quantification measurements reported. This paper presents a summary of the meeting and recommendations. Molecular & Cellular Proteomics 13: 10.1074/mcp.M113.036095, 907–917, 2014.

Carr, Steven A.; Abbateillo, Susan E.; Ackermann, Bradley L.; Borchers, Christoph H.; Domon, Bruno; Deutsch, Eric W.; Grant, Russel; Hoofnagle, Andrew N.; Huttenhain, Ruth; Koomen, John M.; Liebler, Daniel; Liu, Tao; MacLean, Brendan; Mani, DR; Mansfield, Elizabeth; Neubert, Hendrik; Paulovich, Amanda G.; Reiter, Lukas; Vitek, Olga; Aebersold, Ruedi; Anderson, Leigh N.; Bethem, Robert; Blonder, Josip; Boja, Emily; Botelho, Julianne; Boyne, Michael; Bradshaw, Ralph A.; Burlingame, Alma S.; Chan, Daniel W.; Keshishian, Hasmik; Kuhn, Eric; Kingsinger, Christopher R.; Lee, Jerry S.; Lee, Sang-Won; Moritz, Robert L.; Oses-Prieto, Juan; Rifai, Nader; Ritchie, James E.; Rodriguez, Henry; Srinivas, Pothur R.; Townsend, Reid; Van Eyk , Jennifer; Whiteley, Gordon; Wiita, Arun; Weintraub, Susan

2014-01-14T23:59:59.000Z

270

Tile-Based Fisher-Ratio Software for Improved Feature Selection Analysis of Comprehensive Two-Dimensional Gas Chromatography Time-of-Flight Mass Spectrometry Data  

SciTech Connect

Two-dimensional (2D) gas chromatography coupled with time-of-flight mass spectrometry (GC × GC – TOFMS) is a highly capable instrumental platform that produces complex and information-rich multi-dimensional chemical data. The complex data can be overwhelming, especially when many samples (of various sample classes) are analyzed with multiple injections for each sample. Thus, the data must be analyzed in such a way to extract the most meaningful information. The pixel-based and peak table-based algorithmic use of Fisher ratios has been used successfully in the past to reduce the multi-dimensional data down to those chemical compounds that are changing between classes relative to those that are not (i.e., chemical feature selection). We report on the initial development of a computationally fast novel tile-based Fisher-ratio software that addresses challenges due to 2D retention time misalignment without explicitly aligning the data, which is a problem for both pixel-based and peak table- based methods. Concurrently, the tile-based Fisher-ratio software maximizes the sensitivity contrast of true positives against a background of potential false positives and noise. To study this software, eight compounds, plus one internal standard, were spiked into diesel at various concentrations. The tile-based F-ratio software was able to discover all spiked analytes, within the complex diesel sample matrix with thousands of potential false positives, in each possible concentration comparison, even at the lowest absolute spiked analyte concentration ratio of 1.06.

Marney, Luke C.; Siegler, William C.; Parsons, Brendon A.; Hoggard, Jamin C.; Wright, Bob W.; Synovec, Robert E.

2013-10-15T23:59:59.000Z

271

Hydrothermal Liquefaction Oil and Hydrotreated Product from Pine Feedstock Characterized by Heteronuclear Two-Dimensional NMR Spectroscopy and FT-ICR Mass Spectrometry  

SciTech Connect

Hydrothermal liquefaction (HTL) crude oil and hydrotreated product from pine tree farm waste (forest product residual, FPR) have been analyzed by direct infusion electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI FT-ICR MS) in both positive- and negative-ionization modes and high-resolution twodimensional heteronuclear 1H-13C NMR spectroscopy. FT-ICR MS resolves thousands of compounds in complex oils and provides unparalleled compositional details for individual molecules for identification of compound class (heteroatom content), type (number of rings plus double bonds to carbon or double bond equivalents (DBE) and carbon number (degree of alkylation). Heteronuclear 1H-13C NMR spectroscopy provides one-bond and multiple-bond correlations between pairs of 1H and 13C chemical shifts that are characteristic of different organic functional groups. Taken together this information provides a picture of the chemical composition of these oils. Pyrolysis crude oil product from pine wood was characterized for comparison. Generally, pyrolysis oil is comprised of a more diverse distribution of heteroatom classes with higher oxygen number relative to HTL oil as shown by both positive- and negative-ion ESI FT-ICR MS. A total of 300 N1, 594 O1 and 267 O2 compounds were observed as products of hydrotreatment. The relative abundance of N1O1, N1O2, N1O3, N2, N2O1, N2O2 and O3 compounds are reduced to different degrees after hydrotreatment and other higher heteroatom containing species (O4-O10, N1O4, N1O5 and N2O3) are completely removed by hydrotreatment.

Sudasinghe, Nilusha; Cort, John R.; Hallen, Richard T.; Olarte, Mariefel V.; Schmidt, Andrew J.; Schaub, Tanner

2014-12-14T23:59:59.000Z

272

Rapid Quantitation of Ascorbic and Folic Acids in SRM 3280 Multivitamin/Multielement Tablets using Flow-Injection Tandem Mass Spectrometry  

SciTech Connect

RATIONALE: Ascorbic acid (AA) and folic acid (FA) are water-soluble vitamins and are usually fortified in food and dietary supplements. For the safety of human health, proper intake of these vitamins is recommended. Improvement in the analysis time required for the quantitative determination of these vitamins in food and nutritional formulations is desired. METHODS: A simple and fast (~5 min) in-tube sample preparation was performed, independently for FA and AA, by mixing extraction solvent with a powdered sample aliquot followed by agitation, centrifugation, and filtration to recover an extract for analysis. Quantitative detection was achieved by flow-injection (1 L injection volume) electrospray ionization tandem mass spectrometry (ESI-MS/MS) in negative ion mode using the method of standard addition. RESULTS: Method of standard addition was employed for the quantitative estimation of each vitamin in a sample extract. At least 2 spiked and 1 non-spiked sample extract were injected in triplicate for each quantitative analysis. Given an injection-to-injection interval of approximately 2 min, about 18 min was required to complete the quantitative estimation of each vitamin. The concentration values obtained for the respective vitamins in the standard reference material (SRM) 3280 using this approach were within the statistical range of the certified values provided in the NIST Certificate of Analysis. The estimated limit of detections of FA and AA were 13 and 5.9 ng/g, respectively. CONCLUSIONS: Flow-injection ESI-MS/MS was successfully applied for the rapid quantitation of FA and AA in SRM 3280 multivitamin/multielement tablets.

Bhandari, Deepak [ORNL] [ORNL; Kertesz, Vilmos [ORNL] [ORNL; Van Berkel, Gary J [ORNL] [ORNL

2013-01-01T23:59:59.000Z

273

Preliminary design report of a relativistic-Klystron two-beam-accelerator based power source for a 1 TeV center-of-mass next linear collider  

SciTech Connect

A preliminary point design for an 11.4 GHz power source for a 1 TeV center-of-mass Next Linear Collider (NLC) based on the Relativistic-Klystron Two-Beam-Accelerator (RK-TBA) concept is presented. The present report is the result of a joint LBL-LLNL systems study. consisting of three major thrust areas: physics, engineering, and costing. The new RK-TBA point design, together with our findings in each of these areas, are reported.

Yu, S.; Goffeney, N.; Henestroza, E. [Lawrence Berkeley Lab., CA (United States)] [and others

1995-02-22T23:59:59.000Z

274

Accelerators and the Accelerator Community  

E-Print Network (OSTI)

of electrostatic accelerators, while Ernest O. Lawrence (CBP 820 LBNL TBA ACCELERATORS ANDTHE ACCELERATOR COMMUNITY 1 ANDREW SESSLER Lawrence Berkeley

Malamud, Ernest

2009-01-01T23:59:59.000Z

275

Evaluating the mass content and the energy spectrum of a plasma jet in a conical pulse accelerator  

Science Journals Connector (OSTI)

Results are shown of an experimental study concerning the mass content and the energy spectrum of a plasma jet generated in...

V. L. Vereshchagin

1972-06-01T23:59:59.000Z

276

Development of Ion Mobility-mass Spectrometry Instrumentation to Probe the Conformations and Capture the Solution to Gas Phase Transition of Electrosprayed Biomolecules  

E-Print Network (OSTI)

(i.e., peptides and proteins) produced upon ESI and provide new insight into their solution to gas phase evolution. First, fundamental principles of periodic focusing ion mobility spectrometry are comprehensively discussed. Radial ion confinement...

Silveira, Joshua A

2013-11-22T23:59:59.000Z

277

High-Throughput Identification of Bacteria and Yeast by Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry in Conventional Medical Microbiology Laboratories  

Science Journals Connector (OSTI)

...D. J., T. R. Olma, and G. L. Gilbert. 1998. Evaluation of four methods...spectrometry in conventional medical microbiology laboratories. | Matrix-assisted laser...laboratory. | Department of Medical Microbiology, Leiden University Medical Center...

S. Q. van Veen; E. C. J. Claas; Ed J. Kuijper

2010-01-06T23:59:59.000Z

278

Interfacing Chromatography and Mass Spectrometry  

Science Journals Connector (OSTI)

......an active area of 1 to 2...of a known thermal sensitivity...interfacing is the large unbalance...pressure, an atmospheric pressure...to the ion plasma by a stream...occur in the atmospheric pres- sure...in the ion plasma and compete...doubtful that non-volatile...seldom a large number...work in this area using a variety...operated with RF only. The......

William H. McFadden

1979-01-01T23:59:59.000Z

279

Accelerators, Electrodynamics  

NLE Websites -- All DOE Office Websites (Extended Search)

Science and Innovation Capabilities Accelerators, Electrodynamics science-innovationassetsimagesicon-science.jpg Accelerators, Electrodynamics National security depends...

280

E-Print Network 3.0 - alpha spectrometry contribution Sample...  

NLE Websites -- All DOE Office Websites (Extended Search)

Tissue Composition using Peak Intensity... Kortrijk, E. Sabbelaan 53, B-8500 Kortrijk, Belgium. Abstract-- Imaging mass spectrometry or mass spectral... dimension to mass...

Note: This page contains sample records for the topic "accelerator mass spectrometry" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

Determination of Pentachlorophenol Residue in Meat and Fish by Gas Chromatography–Electron Capture Detection and Gas Chromatography–Mass Spectrometry with Accelerated Solvent Extraction  

Science Journals Connector (OSTI)

......soil (3-4), water (5-7), fish...determined by gas-liquid chromatography...the increasing solubility of analytes at...chromatographically pure grade. Water used in all experiments...methanol (3 mL) and water (3 mL). All...under a stream of nitrogen at 45C. Derivatization...Shimadzu-2010 gas chromatograph......

Dongmei Zhao

2014-01-01T23:59:59.000Z

282

Use of Microdosing and Accelerator Mass Spectrometry To Evaluate the Pharmacokinetic Linearity of a Novel Tricyclic GyrB/ParE Inhibitor in Rats  

Science Journals Connector (OSTI)

...Novel Tricyclic GyrB/ParE Inhibitor in Rats Michael A. Malfatti a Victoria Lao a Courtney...preclinical drug candidate (GP-4) in rats as a step toward human microdosing studies...pharmacological dose was assessed in Sprague-Dawley rats. Plasma PKs over the 3 pharmacological...

Michael A. Malfatti; Victoria Lao; Courtney L. Ramos; Voon S. Ong; Kenneth W. Turteltaub

2014-08-18T23:59:59.000Z

283

Current developments in laser ablation-inductively coupled plasma-mass spectrometry for use in geology, forensics, and nuclear nonproliferation research  

SciTech Connect

This dissertation focused on new applications of laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). The diverse fields that were investigated show the versatility of the technique. In Chapter 2, LA-ICP-MS was used to investigate the rare earth element (REE) profiles of garnets from the Broken Hill Deposit in New South Wales, Australia. The normalized REE profiles helped to shed new light on the formation of deposits of sulfide ores. This information may be helpful in identifying the location of sulfide ore deposits in other locations. New sources of metals such as Pg, Zn, and Ag, produced from these ores, are needed to sustain our current technological society. The application of LA-ICP-MS presented in Chapter 3 is the forensics analysis of automotive putty and caulking. The elemental analysis of these materials was combined with the use of Principal Components Analysis (PCA). The PCA comparison was able to differentiate the automotive putty samples by manufacturer and lot number. The analysis of caulk was able to show a differentiation based on manufacturer, but no clear differentiation was shown by lot number. This differentiation may allow matching of evidence in the future. This will require many more analyses and the construction of a database made up of many different samples. The 4th chapter was a study of the capabilities of LA-ICP-MS for fast and precise analysis of particle ensembles for nuclear nonproliferation applications. Laser ablation has the ability to spatially resolve particle ensembles which may contain uranium or other actinides from other particles present in a sample. This is of importance in samples obtained from air on filter media. The particle ensembles of interest may be mixed in amongst dust and other particulates. A problem arises when ablating these particle ensembles directly from the filter media. Dust particles other than ones of interest may be accidentally entrained in the aerosol of the ablated particle ensemble. This would cause the analysis to be skewed. The use of a gelatin substrate allows the ablation a particle ensemble without disturbing other particles or the gelatin surface. A method to trap and ablate particles on filter paper using collodion was also investigated. The laser was used to dig through the collodion layer and into the particle ensemble. Both of these methods fix particles to allow spatial resolution of the particle ensembles. The use of vanillic acid as a possible enhancement to ablation was also studied. A vanillic acid coating of the particles fixed on top of the gelatin substrate was not found to have any positive effect on either signal intensity or precision. The mixing of vanillic acid in the collodion solution used to coat the filter paper increased ablation signal intensity by a factor of 4 to 5. There was little effect on precision, though. The collodion on filter paper method and the gelatin method of resolving particles have shown themselves to be possible tools in fighting proliferation of nuclear weapons and material. Future applications of LA-ICP-MS are only limited by the imagination of the investigator. Any material that can be ablated and aerosolized is a potential material for analysis by LA-ICP-MS. Improvements in aerosol transport, ablation chamber design, and laser focusing can make possible the ablation and analysis of very small amounts of material. This may perhaps lead to more possible uses in forensics. A similar method to the one used in Chapter 3 could perhaps be used to match drug residue to the place of origin. Perhaps a link could be made based on the elements leached from the soil by plants used to make drugs. This may have a specific pattern based on where the plant was grown. Synthetic drugs are produced in clandestine laboratories that are often times very dirty. The dust, debris, and unique materials in the lab environment could create enough variance to perhaps match drugs produced there to samples obtained off the street. Even if the match was not strong enough to be evidence, the knowledge that many sa

Messerly, Joshua D.

2008-08-26T23:59:59.000Z

284

LASER ACCELERATORS  

E-Print Network (OSTI)

UNIVERSITY OF CALIFORNIA Accelerator & Fusion Researchat the 1983 Particle Accelerator Conference, Santa Fe, NM,March 21-23, 1983 LASER ACCELERATORS A.M. Sessler TWO-WEEK

Sessler, A.M.

2008-01-01T23:59:59.000Z

285

accelerators for ATI  

NLE Websites -- All DOE Office Websites (Extended Search)

Building Accelerator Analogs Building Accelerator Analogs Some QuarkNet centers have built "accelerators." No, they are not real but can be used as analogs to real particle accelerators. The real learning comes, of course, when you plan and experiment on your own, but this may give you some starting points. Things to Think About What are your objectives? To make an analogy for particle accelerators? To use classical physics qualitatively? To use classical physics quantitatively? To measure forces, speed, etc.? _______________ Who is your target audience— in an Associate Teacher Institute or their students or both? What do the participants need to know before beginning? Jawbreaker Accelerator Pressurized gas shoots jawbreakers through PVC pipe into a fixed target (brick) or into each other. The original speeds and masses are measured as are those of the resulting particles.

286

Uniformly accelerated black holes  

Science Journals Connector (OSTI)

The static and stationary C metric are examined in a generic framework and their interpretations studied in some detail, especially those with two event horizons, one for the black hole and another for the acceleration. We find that (i) the spacetime of an accelerated static black hole is plagued by either conical singularities or a lack of smoothness and compactness of the black hole horizon, (ii) by using standard black hole thermodynamics we show that accelerated black holes have a higher Hawking temperature than Unruh temperature of the accelerated frame, and (iii) the usual upper bound on the product of the mass and acceleration parameters (<1/27) is just a coordinate artifact. The main results are extended to accelerated rotating black holes with no significant changes.

Patricio S. Letelier and Samuel R. Oliveira

2001-08-24T23:59:59.000Z

287

Compact mass spectrometer for plasma discharge ion analysis  

DOE Patents (OSTI)

A mass spectrometer and methods for mass spectrometry which are useful in characterizing a plasma. This mass spectrometer for determining type and quantity of ions present in a plasma is simple, compact, and inexpensive. It accomplishes mass analysis in a single step, rather than the usual two-step process comprised of ion extraction followed by mass filtering. Ions are captured by a measuring element placed in a plasma and accelerated by a known applied voltage. Captured ions are bent into near-circular orbits by a magnetic field such that they strike a collector, producing an electric current. Ion orbits vary with applied voltage and proton mass ratio of the ions, so that ion species may be identified. Current flow provides an indication of quantity of ions striking the collector.

Tuszewski, Michel G. (Los Alamos, NM)

1997-01-01T23:59:59.000Z

288

Compact mass spectrometer for plasma discharge ion analysis  

DOE Patents (OSTI)

A mass spectrometer and methods are disclosed for mass spectrometry which are useful in characterizing a plasma. This mass spectrometer for determining type and quantity of ions present in a plasma is simple, compact, and inexpensive. It accomplishes mass analysis in a single step, rather than the usual two-step process comprised of ion extraction followed by mass filtering. Ions are captured by a measuring element placed in a plasma and accelerated by a known applied voltage. Captured ions are bent into near-circular orbits by a magnetic field such that they strike a collector, producing an electric current. Ion orbits vary with applied voltage and proton mass ratio of the ions, so that ion species may be identified. Current flow provides an indication of quantity of ions striking the collector. 7 figs.

Tuszewski, M.G.

1997-07-22T23:59:59.000Z

289

Correlation of rocket propulsion fuel properties with chemical composition using comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry followed by partial least squares regression analysis  

SciTech Connect

There is an increased need to more fully assess and control the composition of kerosene based rocket propulsion fuels, namely RP-1 and RP-2. In particular, it is crucial to be able to make better quantitative connections between the following three attributes: (a) fuel performance, (b) fuel properties (flash point, density, kinematic viscosity, net heat of combustion, hydrogen content, etc) and (c) the chemical composition of a given fuel (i.e., specific chemical compounds and compound classes present as a result of feedstock blending and processing). Indeed, recent efforts in predicting fuel performance through modeling put greater emphasis on detailed and accurate fuel properties and fuel compositional information. In this regard, advanced distillation curve (ADC) metrology provides improved data relative to classical boiling point and volatility curve techniques. Using ADC metrology, data obtained from RP-1 and RP-2 fuels provides compositional variation information that is directly relevant to predictive modeling of fuel performance. Often, in such studies, one-dimensional gas chromatography (GC) combined with mass spectrometry (MS) is typically employed to provide chemical composition information. Building on approaches using GC-MS, but to glean substantially more chemical composition information from these complex fuels, we have recently studied the use of comprehensive two dimensional gas chromatography combined with time-of-flight mass spectrometry (GC × GC - TOFMS) to provide chemical composition data that is significantly richer than that provided by GC-MS methods. In this report, by applying multivariate data analysis techniques, referred to as chemometrics, we are able to readily model (correlate) the chemical compositional information from RP-1 and RP-2 fuels provided using GC × GC - TOFMS, to the fuel property information such as that provided by the ADC method and other specification properties. We anticipate that this new chemical analysis strategy will have broad implications for the development of high fidelity composition-property models, leading to an optimized approach to fuel formulation and specification for advanced engine cycles.

Kehimkar, Benjamin; Hoggard, Jamin C.; Marney, Luke C.; Billingsley, Matthew; Fraga, Carlos G.; Bruno, Thomas J.; Synovec, Robert E.

2014-01-31T23:59:59.000Z

290

Determination of ultratrace boron concentrations in uranium oxide by isotope dilution-thermal ionization mass spectrometry using a simplified separation procedure  

Science Journals Connector (OSTI)

Exhaustive reviews on analytical methodologies and mass spectrometric instrumentation for the determination of boron in different matrices such as biological tissues,...1, 4, 5]. It is an established fact that Isotope

Radhika M. Rao; Ankush R. Parab; K. Sasi Bhushan; Suresh K. Aggarwal

2010-06-01T23:59:59.000Z

291

Note: Laser-induced acoustic desorption/synchrotron vacuum ultraviolet photoionization mass spectrometry for analysis of fragile compounds and heavy oils  

Science Journals Connector (OSTI)

In this work we coupled synchrotron vacuum ultraviolet photoionization (SVUV PI) method with the laser-induced acoustic desorption (LIAD) technique for mass spectrometric analysis. The LIAD technique is a “soft” desorption method which could avoid the degradation of analytes during desorption process. Meanwhile SVUV PI is an efficient “soft” ionization source. The new combination of the “soft” desorption technique and “soft” photoionization method is well suitable to reduce the difficulty for interpreting the mass spectra of the fragile compounds and heavy oils.

Liangyuan Jia; Junjie Weng; Zhongyue Zhou; Fei Qi; Wenyue Guo; Lianming Zhao; Juan Chen

2012-01-01T23:59:59.000Z

292

Warming accelerates decomposition of decades-old carbon in forest soils  

Science Journals Connector (OSTI)

...from the canisters on a vacuum line, graphitized for...Keck Carbon Cycle Accelerator Mass Spectrometer...atmospheric testing of nuclear weapons testing ended...Keck Carbon Cycle Accelerator Mass Spectrometer, University...Keck Carbon Cycle Accelerator Mass Spectrometer facility...

Francesca M. Hopkins; Margaret S. Torn; Susan E. Trumbore

2012-01-01T23:59:59.000Z

293

Solid-Phase Extraction Combined with High-Performance Liquid Chromatography?Atmospheric Pressure Chemical Ionization?Mass Spectrometry Analysis of Pesticides in Water:? Method Performance and Application in a Reconnaissance Survey of Residues in Drinking Water in Greater Cairo, Egypt  

Science Journals Connector (OSTI)

Solid-Phase Extraction Combined with High-Performance Liquid Chromatography?Atmospheric Pressure Chemical Ionization?Mass Spectrometry Analysis of Pesticides in Water:? Method Performance and Application in a Reconnaissance Survey of Residues in Drinking Water in Greater Cairo, Egypt ... Each shipment, which included 24 cartridges, weighed <454 g and cost approximately 200 Egyptian pounds ($40 U.S.). ...

Thomas L. Potter; Mahmoud A. Mohamed; Hannah Ali

2006-12-22T23:59:59.000Z

294

Characterization of submicron particles influenced by mixed biogenic and anthropogenic emissions using high-resolution aerosol mass spectrometry: results from CARES  

SciTech Connect

The Carbonaceous Aerosols and Radiative Effects Study (CARES) took place in the Sacramento Valley of California in summer 2010. We present results obtained at Cool, CA, the T1 site of the project ({approx}40 km downwind of urban emissions from Sacramento), where we deployed an Aerodyne high resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS) in parallel with complementary instrumentation to characterize the sources and processes of submicron particles (PM1). Cool is located at the foothill of the Sierra Nevada Mountains, where intense biogenic emissions are periodically mixed with urban outflow transported by daytime southwesterly winds from the Sacramento metropolitan area. The particle mass loading was low (3.0 {micro}gm{sup -3} on average) and dominated by organics (80% of the PM1 mass) followed by sulfate (9.9 %). Organics and sulfate appeared to be externally mixed, as suggested by their different time series (r2 = 0.13) and size distributions. Sulfate showed a bimodal distribution with a droplet mode peaking at {approx}400nm in vacuum aerodynamic diameter (Dva), and a condensation mode at {approx}150 nm, while organics generally displayed a broad distribution in 60-600nm (Dva). New particle formation and growth events were observed almost every day, emphasizing the roles of organics and sulfate in new particle growth, especially that of organics. The organic aerosol (OA) had a nominal formula of C{sub 1}H{sub 1.38}N{sub 0.004}O{sub 0.44}, thus an average organic mass-to-carbon (OM/OC) ratio of 1.70. Two different oxygenated OA (OOA, 90% of total OA mass) and a hydrocarbon-like OA (HOA, 10 %) were identified by Positive matrix factorization (PMF) of the high resolution mass spectra. The more oxidized MO-OOA (O/C = 0.54) corresponded to secondary OA (SOA) primarily influenced by biogenic emissions, while the less oxidized LO-OOA (O/C = 0.42) corresponded to SOA associated with urban transport. The HOA factor corresponded to primary emissions mainly due to local traffic. Twenty three periods of urban plumes from T0 (Sacramento) to T1 (Cool) were identified using the Weather Research and Forecasting model coupled with Chemistry (WRF-Chem). The average PM1 mass loading was much higher in urban plumes (3.9 {micro}gm{sup -3}) than in air masses dominated by biogenic SOA (1.8 {micro}gm{sup -3}). The change in OA mass relative to CO ({Delta}OA/{Delta}CO) varied in the range of 5-196 {micro}gm{sup -3} ppm{sup -1}, reflecting large variability in SOA production. The highest {Delta}OA/{Delta}CO were reached when urban plumes arrived at Cool in the presence of a high concentration of biogenic volatile organic compounds (BVOCs=isoprene+monoterpenes+2-methyl-3-buten-2- ol [MBO]+methyl chavicol). This ratio, which was 77 {micro}gm{sup -3} ppm{sup -1} on average when BVOCs > 2 ppb, is much higher than when urban plumes arrived in a low biogenic VOCs environment (28 {micro}gm{sup -3} ppm{sup -1} when BVOCs < 0.7 ppb) or during other periods dominated by biogenic SOA (40 {micro}gm{sup -3} ppm{sup -1}). The results from this study demon10 strate that SOA formation is enhanced when anthropogenic emissions interact with biogenic precursors.

Setyan, Ari; Zhang, Qi; Merkel, M.; Knighton, Walter B.; Sun, Y.; Song, Chen; Shilling, John E.; Onasch, Timothy B.; Herndon, Scott C.; Worsnop, Douglas R.; Fast, Jerome D.; Zaveri, Rahul A.; Berg, Larry K.; Wiedensohler, A.; Flowers, B. A.; Dubey, Manvendra K.; Subramanian, R.

2012-09-11T23:59:59.000Z

295

Future Accelerators (?)  

E-Print Network (OSTI)

I describe the future accelerator facilities that are currently foreseen for electroweak scale physics, neutrino physics, and nuclear structure. I will explore the physics justification for these machines, and suggest how the case for future accelerators can be made.

John Womersley

2003-08-09T23:59:59.000Z

296

Linear Accelerator  

NLE Websites -- All DOE Office Websites (Extended Search)

Linear Accelerator (LINAC) The core of the LANSCE facility is one of the nation's most powerful proton linear accelerators or LINAC. The LINAC at LANSCE has served the nation since...

297

Development of matrix assisted laser desorption ionization-ion mobility-orthogonal time-of-flight mass spectrometry as a tool for proteomics  

E-Print Network (OSTI)

trend line, it is possible to include peptide masses obtained from lower intensity ion signals in a database search at a higher level of confidence, thus obtaining higher percent protein coverage and higher confidence-level protein identification.7... line correlation data in combination with database search results that found no match for m/z 1880 or 2380 (at 2 missed cleavage) was used to tentatively identify the two signals as 14-25+heme and 8-22+heme respectfully, where no such identification...

Ruotolo, Brandon Thomas

2005-08-29T23:59:59.000Z

298

Characterization of nonpolar lipids and steroids by using laser-induced acoustic desorption/chemical ionization, atmospheric pressure chemical ionization, and electrospray ionization mass spectrometry  

SciTech Connect

Laser-induced acoustic desorption (LIAD) combined with ClMn(H{sub 2}O){sup +} chemical ionization (CI) was tested for the analysis of nonpolar lipids and selected steroids in a Fourier-transform ion cyclotron resonance mass spectrometer (FT-ICR). The nonpolar lipids studied, cholesterol, 5?-cholestane, cholesta-3,5-diene, squalene, and ?-carotene, were found to solely form the desired water replacement product (adduct-H{sub 2}O) upon reaction with the ClMn(H{sub 2}O){sup +} ions. The steroids, androsterone, dehydroepiandrosterone (DHEA), estrone, estradiol, and estriol, also form abundant adduct-H{sub 2}O ions, but less abundant adduct-2H{sub 2}O ions were also observed. Neither (+)APCI nor (+)ESI can ionize the saturated hydrocarbon lipid, cholestane. APCI successfully ionizes the unsaturated hydrocarbon lipids to form exclusively the intact protonated analytes. However, it causes extensive fragmentation for cholesterol and the steroids. The worst case is cholesterol that does not produce any stable protonated molecules. On the other hand, ESI cannot ionize any of the hydrocarbon analytes, saturated or unsaturated. However, ESI can be used to protonate the oxygen-containing analytes with substantially less fragmentation than for APCI in all cases except for cholesterol and estrone. In conclusion, LIAD/ClMn(H{sub 2}O){sup +} chemical ionization is superior over APCI and ESI for the mass spectrometric characterization of underivatized nonpolar lipids and steroids.

Jin, Z.; Daiya, S.; Kenttämaa, Hilkka I.

2011-01-01T23:59:59.000Z

299

LipidMiner: A Software for Automated Identification and Quantification of Lipids from Multiple Liquid Chromatography-Mass Spectrometry Data Files  

SciTech Connect

We have developed a tool for automated, high-throughput analysis of LC-MS/MS data files, which greatly simplifies LC-MS based lipidomics analysis. Our results showed that LipidMiner is accurate and comprehensive in identification and quantification of lipid molecular species. In addition, the workflow implemented in LipidMiner is not limited to identification and quantification of lipids. If a suitable metabolite library is implemented in the library matching module, LipidMiner could be reconfigured as a tool for general metabolomics data analysis. It is of note that LipidMiner currently is limited to singly charged ions, although it is adequate for the purpose of lipidomics since lipids are rarely multiply charged,[14] even for the polyphosphoinositides. LipidMiner also only processes file formats generated from mass spectrometers from Thermo, i.e. the .RAW format. In the future, we are planning to accommodate file formats generated by mass spectrometers from other predominant instrument vendors to make this tool more universal.

Meng, Da; Zhang, Qibin; Gao, Xiaoli; Wu, Si; Lin, Guang

2014-04-30T23:59:59.000Z

300

Standard test method for analysis of isotopic composition of uranium in nuclear-grade fuel material by quadrupole inductively coupled plasma-mass spectrometry  

E-Print Network (OSTI)

1.1 This test method is applicable to the determination of the isotopic composition of uranium (U) in nuclear-grade fuel material. The following isotopic weight percentages are determined using a quadrupole inductively coupled plasma-mass spectrometer (Q-ICP-MS): 233U, 234U, 235U, 236U, and 238U. The analysis can be performed on various material matrices after acid dissolution and sample dilution into water or dilute nitric (HNO3) acid. These materials include: fuel product, uranium oxide, uranium oxide alloys, uranyl nitrate (UNH) crystals, and solutions. The sample preparation discussed in this test method focuses on fuel product material but may be used for uranium oxide or a uranium oxide alloy. Other preparation techniques may be used and some references are given. Purification of the uranium by anion-exchange extraction is not required for this test method, as it is required by other test methods such as radiochemistry and thermal ionization mass spectroscopy (TIMS). This test method is also described i...

American Society for Testing and Materials. Philadelphia

2000-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "accelerator mass spectrometry" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

Liquid Microjunction Surface Sampling Coupled with High-Pressure Liquid Chromatography-Electrospray Ionization-Mass Spectrometry for Analysis of Drugs and Metabolites in Whole-Body Thin Tissue Sections  

SciTech Connect

In this work, a commercially available autosampler was adapted to perform direct liquid microjunction (LMJ) surface sampling followed by a high-pressure liquid chromatography (HPLC) separation of the extract components and detection with electrospray ionization mass spectrometry (ESI-MS). To illustrate the utility of coupling a separation with this direct liquid extraction based surface sampling approach, four different organs (brain, lung, kidney, and liver) from whole-body thin tissue sections of propranolol dosed and control mice were examined. The parent drug was observed in the chromatograms of the surface sampling extracts from all the organs of the dosed mouse examined. In addition, two isomeric phase II metabolites of propranolol (an aliphatic and an aromatic hydroxypropranolol glucuronide) were observed in the chromatograms of the extracts from lung, kidney, and liver. Confirming the presence of one or the other or both of these glucuronides in the extract from the various organs was not possible without the separation. These drug and metabolite data obtained using the LMJ surface sampling/HPLC-MS method and the results achieved by analyzing similar samples by conventional extraction of the tissues and subsequent HPLC-MS analysis were consistent.

Kertesz, Vilmos [ORNL; Van Berkel, Gary J [ORNL

2010-01-01T23:59:59.000Z

302

Accurate determination of Curium and Californium isotopic ratios by inductively coupled plasma quadrupole mass spectrometry (ICP-QMS) in 248Cm samples for transmutation studies  

SciTech Connect

The French Atomic Energy Commission has carried out several experiments including the mini-INCA (INcineration of Actinides) project for the study of minor-actinide transmutation processes in high intensity thermal neutron fluxes, in view of proposing solutions to reduce the radiotoxicity of long-lived nuclear wastes. In this context, a Cm sample enriched in {sup 248}Cm ({approx}97 %) was irradiated in thermal neutron flux at the High Flux Reactor (HFR) of the Laue-Langevin Institute (ILL). This work describes a quadrupole ICP-MS (ICP-QMS) analytical procedure for precise and accurate isotopic composition determination of Cm before sample irradiation and of Cm and Cf after sample irradiation. The factors that affect the accuracy and reproducibility of isotopic ratio measurements by ICP-QMS, such as peak centre correction, detector dead time, mass bias, abundance sensitivity and hydrides formation, instrumental background, and memory blank were carefully evaluated and corrected. Uncertainties of the isotopic ratios, taking into account internal precision of isotope ratio measurements, peak tailing, and hydrides formations ranged from 0.3% to 1.3%. This uncertainties range is quite acceptable for the nuclear data to be used in transmutation studies.

Gourgiotis, A.; Isnard, H.; Aubert, M.; Dupont, E.; AlMahamid, I.; Cassette, P.; Panebianco, S.; Letourneau, A.; Chartier, F.; Tian, G.; Rao, L.; Lukens, W.

2011-02-01T23:59:59.000Z

303

Thermal Desorption-Gas Chromatography or Gas Chromatography-Mass Spectrometry for Analysis of Semi-Volatile Compounds on Atmospheric Particulate Matters  

Science Journals Connector (OSTI)

Abstract A thermal desorption (TD) device was developed and coupled to gas chromatograph (GC) or gas chromatograph-mass spectrometer (GC-MS) for the qualitative and quantitative analysis of semi-volatile organic compounds on atmospheric particulate matters (PM). The TD was operated by direct heating and placed on the top of GC injector, leading to high heating rate and easy transfer of analytes to GC without re-focusing of analytes by cold trap. The materials used for supporting PM samples, desorption temperature and time, and types of sample injection were investigated for the detection of sixteen polycyclic aromatic hydrocarbons (PAHs) and nine n-alkanes. The limits of detection of the proposed TD-GC method were in the range of 0.014–0.094 ng for PAHs, and 0.016–0.026 ng for n-alkanes, with coefficients of correlation above 0.9975. The TD-GC method was applied to the determination of trace \\{PAHs\\} and n-alkanes on PM10 samples from three cities. The recoveries were in the range of 95%–135% (PAHs) and 95%–115% (n-alkanes). Finally, the TD was coupled to GC-MS for comparison of the contents of \\{PAHs\\} and n-alkanes on \\{PMx\\} with different particulate size (x = 10, 5, 2, 1, 0.5, 0.25, 0.1).

Hu MENG; Jing-Hong ZHAO; Chun-Feng DUAN; Liang HAO; Ya-Feng GUAN

2014-01-01T23:59:59.000Z

304

Simultaneous determination of triazine herbicides in rice by high-performance liquid chromatography coupled with high resolution and high mass accuracy hybrid linear ion trap-orbitrap mass spectrometry  

Science Journals Connector (OSTI)

A method was developed for the simultaneous determination of 10 triazine herbicides (cyanazine, simazine, simetryn, metribuzin, atrazine, ametryn, terbuthylazine, prometryn, terbutryn, and dimethametryn) in rice samples by high resolution and high mass accuracy hybrid linear ion trap-Orbitrap mass spectrometer. After extraction with acetonitrile and evaporation, the herbicides were redissolved in n-hexane and purified on a Florisil solid-phase extraction column. All compounds were separated within 12 min, producing more than 11 data points for each herbicide and high mass accuracy quantified ions which the mass errors of absolute value were less than 1.9 ppm in pure solution and 2.1 ppm in the matrix-matched standards solution. The method was validated in terms of the limits of detection and the limits of quantification. The linearity was satisfactory, with a correlation coefficient of >0.9975. Precision and recovery studies were evaluated at three concentration levels for Japonica, Indica, and Glutinous rice matrix. The mean recoveries obtained for all analytes in spiked Xiushui 03, Liangyoupeijiu, and Taihunuo rice samples were 83.3–99.0%, 82.0–99.7%, and 84.2–99.4%, respectively, with relative standard deviation in range 1.7–10.6%, 1.2–10.7%, and 1.9–11.6% for spiked rice samples, respectively. The intra-day precision (n = 5) for the 10 herbicides in rice samples spiked at an intermediate level was between 2.8% and 7.9%, and the inter-day precision over 10 days (n = 10) was between 5.5% and 15.9%.

Ren-Xiang Mou; Ming-Xue Chen; Zhao-Yun Cao; Zhi-Wei Zhu

2011-01-01T23:59:59.000Z

305

Anthropogenic 236U at Rocky Flats, Ashtabula river harbor, and Mersey estuary: three case studies by sector inductively coupled plasma mass spectrometry  

Science Journals Connector (OSTI)

236U (t1/2=2.3×107 y) is formed as a result of thermal neutron capture by 235U. In naturally occurring U ores, where a high neutron flux is present from spontaneous fission of 238U, 236U/238U atom ratios are ~10?4 ppm. In the natural Earth’s crust, unaffected by nuclear fallout, these ratios are expected to be on the order of 10?8 ppm. Reactor-irradiated U, however, exhibits high 236U/238U atom ratios approaching 104 ppm. As a result, the presence of very small quantities of reactor-irradiated U will significantly enhance the ‘background’ 236U/238U atom ratio. When sufficiently elevated 236U/238U ratios are present, the determination of 236U/238U by rapid inductively coupled plasma mass spectrometric (ICPMS) methods is attractive. We have used sector ICPMS at medium resolving power (R=3440) to measure 236U/238U atom ratios with a determination limit of 0.2 ppm. The limiting factors in the measurement are the 235U1H+ isobar and background signal at m/z 236 arising from the 238U+ peak tail. Based upon the analysis of replicates and considerations of possible systematic errors, uncertainties of ±5% are found for 236U/238U atom ratios of 1?100 ppm. This procedure has been demonstrated in studies of anthropogenic 236U in the environment at three locations: (a) offsite soils from the vicinity of the Rocky Flats Environmental Technology site (Golden, Colorado, USA); (b) sediments from the Ashtabula River (Ohio, USA); and (c) sediments from the Mersey estuary (Liverpool, UK). In each of these three locations, definite plumes of elevated 236U/238U are identified and characterized. Maximum 236U/238U atom ratios observed in RFETS-vicinity soils, the Ashtabula River, and the Mersey Estuary are 2.8, 140, and 4.4 ppm, respectively.

M.E Ketterer; K.M Hafer; C.L Link; C.S Royden; W.J Hartsock

2003-01-01T23:59:59.000Z

306

Applications of High-Resolution Electrospray Ionization Mass...  

NLE Websites -- All DOE Office Websites (Extended Search)

High-Resolution Electrospray Ionization Mass Spectrometry to Measurements of Average Oxygen to Carbon Ratios in Applications of High-Resolution Electrospray Ionization Mass...

307

Accelerator Modeling for Discovery | Argonne Leadership Computing...  

NLE Websites -- All DOE Office Websites (Extended Search)

three scientific drivers that require accelerator-based experiments (using the Higgs boson as a new tool for discovery, pursuing the physics associated with neutrino mass,...

308

Acceleration Fund  

NLE Websites -- All DOE Office Websites (Extended Search)

for these Venture Acceleration Fund awards, which have already produced a significant return on investment for the regional companies that have received them," said Padilla....

309

Nuclear Masses in Astrophysics  

E-Print Network (OSTI)

Among all nuclear ground-state properties, atomic masses are highly specific for each particular combination of N and Z and the data obtained apply to a variety of physics topics. One of the most crucial questions to be addressed in mass spectrometry of unstable radionuclides is the one of understanding the processes of element formation in the Universe. To this end, accurate atomic mass values of a large number of exotic nuclei participating in nucleosynthesis are among the key input data in large-scale reaction network calculations. In this paper, a review on the latest achievements in mass spectrometry for nuclear astrophysics is given.

Christine Weber; Klaus Blaum; Hendrik Schatz

2008-12-09T23:59:59.000Z

310

The role of the acquisition methods in the analysis of natural and synthetic steroids and cholic acids by gas chromatography–mass spectrometry  

Science Journals Connector (OSTI)

An exhaustive GC–MS acquisition study was performed, for the simultaneous analysis of natural and synthetic steroids and cholic acids (in order to insert them into the last tierce of our multiresidue analysis system), such as androsterone, ?-estradiol, transdehydroandro-sterone, transdehyroandrosterone, mestranol, dihydrotestosterone, ethinylestradiol, testosterone, norethisterone, estriol, 4-androstene-3,17-dione, gestodene, levonorgestrel, etonogestrel, coprostanol, progesterone, cholesterol, medroxyprogesterone-acetate, lithocholic acid, stigmasterol, cholic acid, chenodeoxycholic acid, ?-sitosterol, ursodeoxycholic acid, 3-hydroxy-7-ketocholic acid and dehydrocholic acid, in total 26 compounds. As novelties to the field, for the trimethylsilyl (TMS) oxime ether/ester derivatives of steroids and cholic acids, at first, a tandem mass spectrometric (MS/MS), multiple reaction monitoring (MRM) type acquisition method has been developed in a single run; also for the first time, the three acquisition techniques, the full scan (FS), the selective ion monitoring (SIM), in our case the multiple ion monitoring (MIM) and the currently optimized MRM methods, have been compared; all three, in parallel, under strictly the same derivatization/instrumental conditions, both in matrix free solutions and municipal wastewater from two Hungarian wastewater treatment plants (WWTPs). Critical evaluation of the three acquisition protocols was collated on their analytical performances and validated under the same conditions. The data of six point calibration curves for FS, MIM and MRM methods, showed that both R2 (0.9995, 0.9858, 0.9975) and RSD (5.3, 5.8, 5.0), for two parallel derivatizations, each injected three times, proved to be independent of the acquisition processes. Whereas, for the method limit of quantification (LOQ) and the instrument limit of quantification (ILQ) values showed considerable differences. LOQ data, were decreasing in the FS, MIM, MRM line (expressed in ng/L), for all steroids and cholic acids. The same trend was determined in terms of the ILQ values. The practical utility of the optimized acquisition techniques was confirmed by the quantitation of the steroids and cholic acids contents of wastewater samples. Results confirmed the importance of the MRM acquisition method, even in comparison to the MIM one: with particular interest in selected cases: avoiding the extreme overestimation of the ?-estradiol (156–1325%) and that of the ethinylestradiol (582–831%) concentrations in the wastewater samples.

N. Andrási; A. Helenkár; A. Vasanits-Zsigrai; Gy. Záray; I. Molnár-Perl

2011-01-01T23:59:59.000Z

311

Current trends in non-accelerator particle physics: 1, Neutrino mass and oscillation. 2, High energy neutrino astrophysics. 3, Detection of dark matter. 4, Search for strange quark matter. 5, Magnetic monopole searches  

SciTech Connect

This report is a compilation of papers reflecting current trends in non-accelerator particle physics, corresponding to talks that its author was invited to present at the Workshop on Tibet Cosmic Ray Experiment and Related Physics Topics held in Beijing, China, April 4--13, 1995. The papers are entitled `Neutrino Mass and Oscillation`, `High Energy Neutrino Astrophysics`, `Detection of Dark Matter`, `Search for Strange Quark Matter`, and `Magnetic Monopole Searches`. The report is introduced by a survey of the field and a brief description of each of the author`s papers.

He, Yudong [California Univ., Berkeley, CA (United States)]|[Lawrence Berkeley Lab., CA (United States)

1995-07-01T23:59:59.000Z

312

Ultraviolet photodissociation enhances top?down mass...  

NLE Websites -- All DOE Office Websites (Extended Search)

Ultraviolet photodissociation enhances top-down mass spectrometry as demonstrated on green fluorescent protein variants Xibei Dang 1,2 and Nicolas L. Young 1 1 Ion Cyclotron...

313

Determination of actinide elements at femtogram per gram levels in environmental samples by on-line solid phase extraction and sector-field-inductively coupled plasma-mass spectrometry  

Science Journals Connector (OSTI)

An on-line solid phase extraction method has been developed for the determination of 232Th, 237Np, 238U, 239Pu, 240Pu, 241Am and 243Am in biological certified reference material using a column containing TRU-Spec™ resin coupled with sector-field inductively coupled plasma-mass spectrometry. Absolute detection limits were 0.7, 0.85, 0.6, and 0.65 fg for 237Np, 239Pu, 241Am and 243Am, respectively. The 239Pu was determined in NIST Human Liver (963±297 fg g?1 compared with a certified value of 848±161 fg g?1) using a dry and wet ashing sample preparation method, and in a spiked cabbage reference material (394±54 fg g?1 compared to an indicative value of 467 fg g?1) using microwave digestion. Sequential separation of Pu and U was achieved by on-column reduction of Pu with titanium(III) chloride and elution in 4 M \\{HCl\\} to facilitate the determination of 239Pu in samples containing high levels of 238U, thereby eliminating the interference of 238U1H+ at m/z 239. The sequential elution procedure was used to determine 239Pu in NIST human lung (814±55 fg g?1 compared with a certified range of 227–951 fg g?1) and NIST Rocky Flats Soil (2423±137 fg g?1 compared with a certified value of 3307±248 fg g?1).

Jason B Truscott; Phil Jones; Ben E Fairman; E.Hywel Evans

2001-01-01T23:59:59.000Z

314

Chip-based genotyping by mass spectrometry  

Science Journals Connector (OSTI)

...use. A piezo-electric...using a piezo-electric pipette...molecules. A piezo-electric pipette was used for...indicating uneven distribution...the Department of Energy and National Institutes of Health planning groups ( 1998...

Kai Tang; Dong-Jing Fu; Dominique Julien; Andreas Braun; Charles R. Cantor; Hubert Köster

1999-01-01T23:59:59.000Z

315

Improvements in Inductively Coupled Plasma - Mass Spectrometry...  

NLE Websites -- All DOE Office Websites (Extended Search)

Simpler sampling can reduce the hazards, costs and complexity of site assessment, and that's what's on the way for an established analytical technique. Scientists are modifying...

316

Signatures for Mass Spectrometry Data Quality  

SciTech Connect

Ensuring data quality and proper instrument functionality is a prerequisite for scientific investigation. Manual validation for quality assurance is time consuming, expensive and subjective. Metrics for describing various features of LC-MS data have been developed to assist operators in discriminating poor (out of control) and good (in control) datasets. However, the wide variety of instrument specifications and LC-MS configurations precludes applying a simple range of acceptable values or cutoffs for such metrics. We explored a variety of statistical modeling approaches to predict the quality of LC-MS data. Using 1164 manually classified quality control (QC) LC-MS datasets, we fit logistic regression classification models to the QC data to predict whether a dataset is in or out of control. Model parameters were optimized by minimizing a loss function that accounts for the tradeoff between false positive and false negative errors. The optimal logistic regression classifier models detected bad data sets with high sensitivity (i.e. low false negative rate) while maintaining high specificity (i.e. controlling the false positive rate). As an example, predictions for Velos-Orbitrap instrumentation data had a sensitivity of 93.7% in detecting out of control datasets with a false positive rate of 8.3%. In comparison, we investigated the performance of several single metrics in predicting dataset quality. While maintaining a sensitivity of 93.7%, the corresponding false positive rates for these single-metric models unacceptably ranged from 32% to 97.7%. Finally, we evaluated the performance of the

Amidan, Brett G.; Orton, Daniel J.; Lamarche, Brian L.; Monroe, Matthew E.; Moore, Ronald J.; Venzin, Alexander M.; Smith, Richard D.; Sego, Landon H.; Tardiff, Mark F.; Payne, Samuel H.

2014-03-10T23:59:59.000Z

317

Improving liquid chromatography-mass spectrometry sensitivity...  

NLE Websites -- All DOE Office Websites (Extended Search)

sensitivity using a subambient pressure ionization with nanoelectrospray (SPIN Abstract: In this work the Subambient Pressure Ionization with Nanoelectrospray (SPIN) ion...

318

Accelerate Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

the next year, the U.S. Department of Energy, the Council on Competitiveness and the Alliance to Save Energy will join forces to undertake Accelerate Energy Productivity 2030 - an...

319

Fate and Distribution of 2-Amino-1-methyl-6-phenylimidazo[4,5-b]pyridine in Mice at a Human Dietary Equivalent Dose  

Science Journals Connector (OSTI)

...sensitivity offered by accelerator mass spectrometry...first example of how accelerator mass spectrometry can...amino-imidazoazaarenes; AMS, accelerator mass spectrometry...AMS is a low energy nuclear physics technique that...tubes, dried under vacuum, and then converted...

Kenneth W. Turteltaub; John S. Vogel; Christopher E. Frantz; and Nancy Shen

1992-09-01T23:59:59.000Z

320

Accelerated Testing Validation  

E-Print Network (OSTI)

the University of California. Accelerated Testing Validationmaterials requires relevant Accelerated Stress Tests (ASTs),

Mukundan, Rangachary

2013-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "accelerator mass spectrometry" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

LTQ-XL mass spectrometry proteome analysis expands the Pseudomonas aeruginosa AmpR regulon to include cyclic di-GMP phosphodiesterases and phosphoproteins, and identifies novel open reading frames  

Science Journals Connector (OSTI)

Abstract Pseudomonas aeruginosa is well known for its antibiotic resistance and intricate regulatory network, contributing to its success as an opportunistic pathogen. This study is an extension of our transcriptomic analyses (microarray and RNA-Seq) to understand the global changes in PAO1 upon deleting a gene encoding a transcriptional regulator AmpR, in the presence and absence of ?-lactam antibiotic. This study was performed under identical conditions to explore the proteome profile of the ampR deletion mutant (PAO?ampR) using LTQ-XL mass spectrometry. The proteomic data identified ~ 53% of total PAO1 proteins and expanded the master regulatory role of AmpR in determining antibiotic resistance and multiple virulence phenotypes in P. aeruginosa. AmpR proteome analysis identified 853 AmpR-dependent proteins, which include 102 transcriptional regulators and 21 two-component system proteins. AmpR also regulates cyclic di-GMP phosphodiesterases (PA4367, PA4969, PA4781) possibly affecting major virulence systems. Phosphoproteome analysis also suggests a significant role for AmpR in Ser, Thr and Tyr phosphorylation. These novel mechanisms of gene regulation were previously not associated with AmpR. The proteome analysis also identified many unannotated and misannotated \\{ORFs\\} in the P. aeruginosa genome. Thus, our data sheds light on important virulence regulatory pathways that can potentially be exploited to deal with P. aeruginosa infections. Biological significance The AmpR proteome data not only confirmed the role of AmpR in virulence and resistance to multiple antibiotics, but also expanded the perimeter of AmpR regulon. The data presented here points to the role of AmpR in regulating cyclic di-GMP levels and phosphorylation of Ser, Thr and Tyr, adding another dimension to the regulatory functions of AmpR. We also identify some previously unannotated/misannotated \\{ORFs\\} in the P. aeruginosa genome, indicating the limitations of existing ORF analyses software. This study will contribute towards understanding complex genetic organization of P. aeruginosa. Whole genome proteomic picture of regulators at higher nodal positions in the regulatory network will not only help us link various virulence phenotypes but also design novel therapeutic strategies.

Hansi Kumari; Senthil K. Murugapiran; Deepak Balasubramanian; Lisa Schneper; Massimo Merighi; David Sarracino; Stephen Lory; Kalai Mathee

2014-01-01T23:59:59.000Z

322

Application Acceleration  

NLE Websites -- All DOE Office Websites (Extended Search)

Acceleration Acceleration on Current and Future Cray Platforms Alice Koniges, Robert Preissl, Jihan Kim, Lawrence Berkeley National Laboratory David Eder, Aaron Fisher, Nathan Masters, Velimir Mlaker, Lawrence Livermore National Laboratory Stephane Ethier, Weixing Wang, Princeton Plasma Physics Laboratory Martin Head-Gordon, University of California, Berkeley and Nathan Wichmann, Cray Inc. ABSTRACT: Application codes in a variety of areas are being updated for performance on the latest architectures. We describe current bottlenecks and performance improvement areas for applications including plasma physics, chemistry related to carbon capture and sequestration, and material science. We include a variety of methods including advanced hybrid parallelization using multi-threaded MPI, GPU acceleration, libraries and auto- parallelization compilers. KEYWORDS: hybrid

323

A New Method of Accelerated Bayesian Inference for Comparable Mass Binaries in both Ground and Space-Based Gravitational Wave Astronomy  

E-Print Network (OSTI)

With the advance in computational resources, Bayesian inference is increasingly becoming the standard tool of practise in GW astronomy. However, algorithms such as Markov Chain Monte Carlo (MCMC) require a large number of iterations to guarantee convergence to the target density. Each chain demands a large number of evaluations of the likelihood function, and in the case of a Hessian MCMC, calculations of the Fisher information matrix for use as a proposal distribution. As each iteration requires the generation of at least one gravitational waveform, we very quickly reach a point of exclusion for current Bayesian algorithms, especially for low mass systems where the length of the waveforms is large and the waveform generation time is on the order of seconds. This suddenly demands a timescale of many weeks for a single MCMC. As each likelihood and Fisher information matrix calculation requires the evaluation of noise-weighted scalar products, we demonstrate that by using the linearity of integration, and the fact that more than 90% of the generation time is spent at frequencies less that one third of the maximum, we can construct composite integrals that speed up the MCMCs for comparable mass binaries by a factor of between 3.5 and 5.5, depending on the waveform length. This method is both source and detector type independent, and can be applied to any waveform that displays significant frequency evolution, such as stellar mass binaries with Advanced LIGO/Virgo, as well as supermassive black holes with eLISA

Edward K. Porter

2014-11-03T23:59:59.000Z

324

About Accelerators | Jefferson Lab  

NLE Websites -- All DOE Office Websites (Extended Search)

Accelerator Brochure top-right bottom-left-corner bottom-right-corner About Accelerators Jefferson Lab is home to two superconducting radiofrequency accelerators: the...

325

GPU accelerated cardiac electrophysiology  

E-Print Network (OSTI)

OF THE THESIS GPU Accelerated Cardiac Electrophysiology bySAN DIEGO GPU Accelerated Cardiac Electrophysiology A thesistoolkit for developing GPU accelerated programs called CUDA,

Lionetti, Fred

2010-01-01T23:59:59.000Z

326

Review of ion accelerators  

SciTech Connect

The field of ion acceleration to higher energies has grown rapidly in the last years. Many new facilities as well as substantial upgrades of existing facilities have extended the mass and energy range of available beams. Perhaps more significant for the long-term development of the field has been the expansion in the applications of these beams, and the building of facilities dedicated to areas outside of nuclear physics. This review will cover many of these new developments. Emphasis will be placed on accelerators with final energies above 50 MeV/amu. Facilities such as superconducting cyclotrons and storage rings are adequately covered in other review papers, and so will not be covered here.

Alonso, J.

1990-06-01T23:59:59.000Z

327

Fermilab | Illinois Accelerator Research Center | Accelerators...  

NLE Websites -- All DOE Office Websites (Extended Search)

Accelerators and Society Physicists have been inventing new types of accelerators to propel charged particles to higher and higher energies for more than 80 years. Today, besides...

328

Gas chromatographic-mass spectrometric determination of benzo[a]pyrene and chrysene diol epoxide globin adducts in humans.  

Science Journals Connector (OSTI)

...Orlando, FL Abstract 5104: Serum metabolomic profiles acquired by gas chromatography-mass spectrometry (GC-MS) distinguish patients...disease. Accompanying clinical data were collected prospectively. Gas chromatography-mass spectrometry (GC-MS) spectra were acquired...

A A Melikian; P Sun; C Pierpont; S Coleman; S S Hecht

1997-10-01T23:59:59.000Z

329

Argonne Accelerator Institute  

NLE Websites -- All DOE Office Websites (Extended Search)

Useful Links Useful Links Argonne National Laboratory Accelerator Sites Conferences Advanced Photon Source (APS) Argonne Wakefield Accelerator (AWA) Argonne Tandem Linear Accelerator System (ATLAS) High Energy Physics Division RIA (????) Link to JACoW (Joint Accelerator Conferences Website) Fermi National Accelerator Laboratory Fermilab-Argonne Collaboration Accelerator Physics Center Workshops Other Accelerator Institutes Energy Recovering Linacs Center for Advance Studies of Accelerators (Jefferson Labs) Center for Beam Physics (LBNL) Accelerator Test Facility (BNL) The Cockcroft Institute (Daresbury, UK) John Adams Institute (Rutherford, UK) ERL2009 to be held at Cornell ERL2007 ERL2005 DOE Laboratory with Accelerators Fermilab Stanford Linear Accelerator Center Brookhaven National Laboratory

330

Chemical Accelerators The phrase "chemical accelerators"  

E-Print Network (OSTI)

Meetings Chemical Accelerators The phrase "chemical accelerators" is scarcely older than for one or two dozen people grew to include nearly a hundred. Chemical accelerators is a name sug- gested-volt region. Thus chemical accelerators can provide the same type of information for elemen- tary chemical

Zare, Richard N.

331

Accelerating Solutions  

NLE Websites -- All DOE Office Websites (Extended Search)

Solutions From vehicles on the road to the energy that powers them, Oak Ridge National Laboratory innovations are advancing American transportation. Oak Ridge National Laboratory is making an impact on everyday America by enhancing transportation choices and quality of life. Through strong collaborative partnerships with industry, ORNL research and development efforts are helping accelerate the deployment of a new generation of energy efficient vehicles powered by domestic, renewable, clean energy. EPA ultra-low sulfur diesel fuel rule ORNL and the National Renewable Energy Laboratory co-led a comprehensive research and test program to determine the effects of diesel fuel sulfur on emissions and emission control (catalyst) technology. In the course of this program, involving

332

Accelerating projects  

SciTech Connect

This chapter describes work at ORNL in the period around 1950, when the laboratory was evolving from its original mission of research aimed at producing the atomic bomb, to a new mission, which in many ways was unclear. The research division from Y-12 merged with the laboratory, which gave an increased work force, access to a wide array of equipment, and the opportunity to work on a number of projects related to nuclear propulsion. The first major project was for a nuclear aircraft. From work on this program, a good share of the laboratories work in peaceful application of nuclear energy would spring. A major concern was the development of light weight shielding to protect the crew and materials in such a plane. To do such shielding work, the laboratory employed existing, and new reactors. The original plans called for the transfer of reactor work to Argonne, but because of their own research load, and the needs of the lab, new reactor projects were started at the lab. They included the Low Intensity Test Reactor, the Swimming Pool Reactor, the Bulk Shielding Reactor, the Tower Shielding Facility, and others. The laboratory was able to extend early work on calutrons to accelerator development, pursuing both electrostatic accelerators and cyclotrons. The aircraft project also drove the need for immense quantities of scientific data, with rapid analysis, which resulted the development of divisions aimed at information support and calculational support. The laboratory also expanded its work in the effects of radiation and cells and biological systems, as well as in health physics.

Not Available

1992-01-01T23:59:59.000Z

333

Teleportation of Accelerated Information  

E-Print Network (OSTI)

A theoretical quantum teleportation protocal is suggested to teleport accelerated and non-accelerated information over different classes of accelerated quantum channels. For the accelerated information, it is shown that the fidelity of the teleported state increases as the entanglement of the initial quantum channel increases. However as the difference between the accelerated channel and the accelerated information decreases the fidelity increases. The fidelity of the non accelerated information increases as the entanglement of the initial quantum channel increases, while the accelerations of the quantum channel has a little effect. The possibility of sending quantum information over accelerated quantum channels is much better than sending classical information.

N. Metwally

2012-06-17T23:59:59.000Z

334

for sequence accelerators  

E-Print Network (OSTI)

Wynn's -algorithm for sequence accelerators using high precision arithmetic Rachel Baumann University of Arizona Wynn's -algorithm for sequence accelerators using high precision arithmetic Rachel Baumann University of Arizona April 17, 2012 #12;Wynn's -algorithm for sequence accelerators using high

Zakharov, Vladimir

335

COLLECTIVE PHENOMENA IN ACCELERATORS  

E-Print Network (OSTI)

Proc. 1971 Particle Accelerator Conference, IEEE Trans. onConference on High-Energy Accelerators) 1971 (CERN, Geneva,and P. R. Zenkevich, Particle Accelerators b 1 (1972). M. S.

Sessler, Andrew M.

2008-01-01T23:59:59.000Z

336

High-Current Accelerators  

E-Print Network (OSTI)

F i g . 13 F i g . 14 A 48 ACCELERATOR F i g . 25 F i g . 16supply. Extrapolation of accelerator energy and current9 . A-48 high-current accelerator, low-velocity end. Fig.

Lawrence, Ernest O.

1955-01-01T23:59:59.000Z

337

Argonne Accelerator Institute  

NLE Websites -- All DOE Office Websites (Extended Search)

AAI Home AAI Home Welcome Accelerators at Argonne Mission Organization History Document Collection Conferences & Workshops Beams and Applications Seminar Argonne-Fermilab Collaboration Lee Teng Scholarship Program Useful Links Argonne Accelerator Institute In 2006, Argonne Laboratory Director Robert Rosner formed the AAI as a focal point for accelerator initiatives. The institute works to utilize Argonne's extensive accelerator resources, to enhance existing facilities, to determine the future of accelerator development and construction, and to oversee a dynamic and acclaimed accelerator physics portfolio. More Information for: Members * Students Industrial Collaborators - Working with Argonne Link to: Accelerators for America's Future Upcoming Events and News 4th International Particle Accelerator Conference (IPAC'13)

338

Fermilab | Science | Particle Accelerators  

NLE Websites -- All DOE Office Websites (Extended Search)

Particle Accelerators Main Injector As America's particle physics laboratory, Fermilab operates and builds powerful particle accelerators for investigating the smallest things...

339

Focusing in Linear Accelerators  

DOE R&D Accomplishments (OSTI)

Review of the theory of focusing in linear accelerators with comments on the incompatibility of phase stability and first-order focusing in a simple accelerator.

McMillan, E. M.

1950-08-24T23:59:59.000Z

340

Lab announces Venture Acceleration  

NLE Websites -- All DOE Office Websites (Extended Search)

Inc., and ThermaSun Inc. as recipients of awards from the Los Alamos National Security, LLC Venture Acceleration Fund. The Laboratory's Venture Acceleration Fund provides...

Note: This page contains sample records for the topic "accelerator mass spectrometry" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

Accelerated overlap fermions  

Science Journals Connector (OSTI)

Numerical evaluation of the overlap Dirac operator is difficult since it contains the sign function ?(Hw) of the Hermitian Wilson-Dirac operator Hw with a negative mass term. The problems are due to Hw having very small eigenvalues on the equilibrium background configurations generated in current day Monte Carlo simulations. Since these are a consequence of the lattice discretization and do not occur in the continuum version of the operator, we investigate in this paper to what extent the numerical evaluation of the overlap can be accelerated by making the Wilson-Dirac operator more continuum-like. Specifically, we study the effect of including the clover term in the Wilson-Dirac operator and smearing the link variables in the irrelevant terms. In doing so, we have obtained a factor of 2 speedup by moving from the Wilson action to a fat link irrelevant clover action as the overlap kernel.

Waseem Kamleh; David H. Adams; Derek B. Leinweber; Anthony G. Williams

2002-07-09T23:59:59.000Z

342

Muon Collider Progress: Accelerators  

SciTech Connect

A muon collider would be a powerful tool for exploring the energy-frontier with leptons, and would complement the studies now under way at the LHC. Such a device would offer several important benefits. Muons, like electrons, are point particles so the full center-of-mass energy is available for particle production. Moreover, on account of their higher mass, muons give rise to very little synchrotron radiation and produce very little beamstrahlung. The first feature permits the use of a circular collider that can make efficient use of the expensive rf system and whose footprint is compatible with an existing laboratory site. The second feature leads to a relatively narrow energy spread at the collision point. Designing an accelerator complex for a muon collider is a challenging task. Firstly, the muons are produced as a tertiary beam, so a high-power proton beam and a target that can withstand it are needed to provide the required luminosity of ~1 × 10{sup 34} cm{sup –2}s{sup –1}. Secondly, the beam is initially produced with a large 6D phase space, which necessitates a scheme for reducing the muon beam emittance (“cooling”). Finally, the muon has a short lifetime so all beam manipulations must be done very rapidly. The Muon Accelerator Program, led by Fermilab and including a number of U.S. national laboratories and universities, has undertaken design and R&D activities aimed toward the eventual construction of a muon collider. Design features of such a facility and the supporting R&D program are described.

Zisman, Michael S.

2011-09-10T23:59:59.000Z

343

I. ACCELERATION A. Introduction  

E-Print Network (OSTI)

I. ACCELERATION A. Introduction Following cooling and initial bunch compression, the beams must be rapidly accelerated. The acceleration needed for a Higgs collider is probably the most conventional part undertaken. A sequence of linacs would work, but would be expensive. Some form of circulating acceleration

McDonald, Kirk

344

Superconducting Radiofrequency (SRF) Accelerator Cavities  

SciTech Connect

Charlie Reece, an accelerator technology scientist, explains how superconducting radiofrequency accelerator cavities work.

Reece, Charlie

2013-05-03T23:59:59.000Z

345

Superconducting Radiofrequency (SRF) Accelerator Cavities  

ScienceCinema (OSTI)

Charlie Reece, an accelerator technology scientist, explains how superconducting radiofrequency accelerator cavities work.

Reece, Charlie

2014-05-22T23:59:59.000Z

346

Quantification of Methadone and its Metabolite 2-Ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine in Third Instar Larvae of Lucilia sericata (Diptera: Calliphoridae) Using Liquid Chromatography-Tandem Mass Spectrometry  

Science Journals Connector (OSTI)

......Sensitivity and Specificity Substance Abuse Detection methods Tandem Mass...substances such as drugs-of-abuse, ethanol, or benzodiazepines...detected in human remains of a young man suspected to consume heroin...importance in Medellin, Colombia. Internet J. Forensic Med. Toxicol......

Matthias Gosselin; Maria del Mar Ramirez Fernandez; Sarah M.R. Wille; Nele Samyn; Gert De Boeck; Benoit Bourel

2010-09-01T23:59:59.000Z

347

Fermilab | Illinois Accelerator Research Center | Illinois Accelerator  

NLE Websites -- All DOE Office Websites (Extended Search)

photo: IARC photo: IARC As envisioned, the Illinois Accelerator Research Center will provide approximately 83,000 square feet of technical, office and classroom space for scientists and industrial partners. The Illinois Accelerator Research Center (IARC) is a new accelerator research facility being built at Fermi National Accelerator Laboratory. At the Illinois Accelerator Research Center, scientists and engineers from Fermilab, Argonne and Illinois universities will work side by side with industrial partners to research and develop breakthroughs in accelerator science and translate them into applications for the nation's health, wealth and security. Located on the Fermilab campus this 83,000 square foot, state-of-the-art facility will house offices, technical and educational space to study

348

Fermilab | Science | Particle Accelerators | Fermilab's Accelerator...  

NLE Websites -- All DOE Office Websites (Extended Search)

It produces the world's most powerful, high-energy neutrino beam and provides proton beams for various experiments and R&D programs. Fermilab's accelerator complex delivers...

349

Fermilab | Science | Particle Accelerators | Leading Accelerator...  

NLE Websites -- All DOE Office Websites (Extended Search)

Fermilab scientists and engineers develop particle accelerators to produce beams to take particle physics to the next level, collaborating with scientists and...

350

An Inertial Reaction to Cosmological Accelerations  

E-Print Network (OSTI)

Mach's "fixed stars" are actually not fixed at all. The distant clusters of galaxies are not only receding from each observer but they are also accelerating since the rate of cosmological expansion is not constant. If the distant cosmic masses in someway constitute the frame of inertial reference then an additional force should be generated among local bodies in reaction to the apparent cosmological accelerations of the distant galaxies.

Scott Funkhouser

2005-05-17T23:59:59.000Z

351

Accurate correction of magnetic field instabilities for high-resolution isochronous mass measurements in storage rings  

E-Print Network (OSTI)

Isochronous mass spectrometry (IMS) in storage rings is a successful technique for accurate mass measurements of short-lived nuclides with relative precision of about $10^{-5}-10^{-7}$. Instabilities of the magnetic fields in storage rings are one of the major contributions limiting the achievable mass resolving power, which is directly related to the precision of the obtained mass values. A new data analysis method is proposed allowing one to minimise the effect of such instabilities. The masses of the previously measured at the CSRe $^{41}$Ti, $^{43}$V, $^{47}$Mn, $^{49}$Fe, $^{53}$Ni and $^{55}$Cu nuclides were re-determined with this method. An improvement of the mass precision by a factor of $\\sim 1.7$ has been achieved for $^{41}$Ti and $^{43}$V. The method can be applied to any isochronous mass experiment irrespective of the accelerator facility. Furthermore, the method can be used as an on-line tool for checking the isochronous conditions of the storage ring.

P. Shuai; H. S. Xu; Y. H. Zhang; Yu. A. Litvinov; M. Wang; X. L. Tu; K. Blaum; X. H. Zhou; Y. J. Yuan; G. Audi; X. L. Yan; X. C. Chen; X. Xu; W. Zhang; B. H. Sun; T. Yamaguchi; R. J. Chen; C. Y. Fu; Z. Ge; W. J. Huang; D. W. Liu; Y. M. Xing; Q. Zeng

2014-07-13T23:59:59.000Z

352

A theory of metrics with maximal acceleration  

E-Print Network (OSTI)

We present a geometric theory for spacetimes whose world lines associated with physical particles have an upper bound for the proper acceleration. After some fundamental remarks on the requirements that classical dynamics for point particles must hold good, the notion of generalized metric and a theory of maximal acceleration are introduced. A perturbative approach to metrics of maximal acceleration is discussed. Then several of their physical and kinematical properties are investigated. These include a discussion of the fundamental causal theory concepts and the introduction of the associated notions of Euclidean length and celerity function. Finally, we discuss the corresponding modification of the Einstein's mass-energy relation.

Ricardo Gallego Torromé

2014-03-06T23:59:59.000Z

353

Argonne Accelerator Institute  

NLE Websites -- All DOE Office Websites (Extended Search)

Research and Development Research and Development Click to download a PDF version of this document. PDF Focus Research Areas Fundamental Accelerator Physics: Theory Importance Accelerator physics research is normally associated with specific accelerator projects. As a scientific discipline, however, it is useful to study fundamental accelerator phenomena decoupled, as much as possible, from specific project aspects. Pursuit of fundamental accelerator physics in this sense has contributed significantly to the advance of the accelerator physics knowledgebase during the last several decades, clarifying the limitations and suggesting ways to overcome those limitations. Such basic research tends to be discouraged in a project-driven environment. For sustained and significant progress in

354

Radio-frequency glow discharge spectrometry:: A critical review  

Science Journals Connector (OSTI)

This paper presents a critical review of analytical radio frequency glow discharge spectrometry (rf-GDS). The historical foundations of rf-GDS are described, and current knowledge of the fundamental physics of analytical rf glow discharges is discussed. Additionally, instrumentation, methodologies, and applications of rf glow discharge optical emission spectrometry (rf-GDOES) and mass spectrometry (rf-GDMS) are reviewed. Although other rf-GDS techniques have appeared [e.g. rf glow discharge atomic absorption spectrophotometry (rf-GDAAS)], the emphasis is placed upon rf-GDOES and rf-GDMS, because they have received by far the most interest from analytical chemical metrologists. This review also provides explanations of some developments that are needed for further progress in the field of analytical rf-GDS.

Michael R. Winchester; Richard Payling

2004-01-01T23:59:59.000Z

355

E-Print Network 3.0 - atomic masses library Sample Search Results  

NLE Websites -- All DOE Office Websites (Extended Search)

21 ATOMS... ... Source: UK Fusion Center at Culham (UKAEA) Collection: Plasma Physics and Fusion 27 Modeling Mass Spectrometry-Based Protein Analysis Jan Eriksson and David Feny...

356

RHIC | Accelerator Complex  

NLE Websites -- All DOE Office Websites (Extended Search)

RHIC Accelerators RHIC Accelerators The Relativistic Heavy Ion Collider complex is actually composed of a long "chain" of particle accelerators Heavy ions begin their travels in the Electron Beam Ion Source accelerator (1). The ions then travel to the small, circular Booster (3) where, with each pass, they are accelerated to higher energy. From the Booster, ions travel to the Alternating Gradient Synchrotron (4), which then injects the beams via a beamline (5) into the two rings of RHIC (6). In RHIC, the beams get a final accelerator "kick up" in energy from radio waves. Once accelerated, the ions can "orbit" inside the rings for hours. RHIC can also conduct colliding-beam experiments with polarized protons. These are first accelerated in the Linac (2), and further in the Booster (3), AGS (4), and

357

Fermilab | Tevatron | Accelerator  

NLE Websites -- All DOE Office Websites (Extended Search)

particle accelerator in the world before it shut down on Sept. 29, 2011. It accelerated beams of protons and antiprotons to 99.999954 percent of the speed of light around a...

358

History of Proton Linear Accelerators  

E-Print Network (OSTI)

much. References 1. Linear Accelerators, edited by P. M .at the 1986 Linear Accelerator Conference, SLAC, Stanford,HISTORY OF PROTON LINEAR ACCELERATORS Luis W. Alvarez TWO-

Alvarez, Luis W.

1987-01-01T23:59:59.000Z

359

LARGE-APERTURE D- ACCELERATORS  

E-Print Network (OSTI)

Vignetted current profile at accelerator entrance aperture 'LARGE-APERTURE D" ACCELERATORS* 0. A. Anderson" " Lawrencen i a 9-1720 Abstract Accelerator designs are described for

Anderson, O.A.

2010-01-01T23:59:59.000Z

360

Beam Dynamics for Induction Accelerators  

E-Print Network (OSTI)

Dynamics for Induction Accelerators Edward P. Lee Lawrencea natural candidate accelerator for a heavy ion fusion (HIF)words: Fusion, Induction, Accelerators, Dynamics This work

Lee, E.P.

2014-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "accelerator mass spectrometry" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

Shielding of proton accelerators  

Science Journals Connector (OSTI)

......capabilities of an accelerator control system...meant to undergo a nuclear interaction within...the axis of the vacuum chamber. The beam...of high-energy accelerators. Nucl. Instrum...Series, Group I: Nuclear and Particle Physics-Schopper...100-250 MeV proton accelerators: double differential......

Stefano Agosteo; Matteo Magistris; Marco Silari

2011-07-01T23:59:59.000Z

362

Particle acceleration in the heliosphere  

Science Journals Connector (OSTI)

The heliosphere is filled with supersonic solar wind that forms shocks wherever it encounters obstacles be they a high speed Coronal Mass Ejection (CME) or regions where fastsolar wind encounters slower-moving solar wind. Energetic particles (> 10s of keV/nuc to 10s of MeV/nuc) associated with these shocks form a test bed for understanding particle acceleration since the shock properties can often be measured and energetic particle composition compared to candidate seed populations. Over the past 15-20 years a wide body of evidence has emerged showing that generally the seed population is the suprathermal ion pool at energies above the bulk solar wind. Understanding the interplanetary suprathermal ion population is therefore a critical step in fully understanding the physical mechanisms that accelerate particles in interplanetary space.

G. M. Mason; M. I. Desai; R. A. Mewaldt; C. M. S. Cohen

2013-01-01T23:59:59.000Z

363

Argonne Accelerator Institute  

NLE Websites -- All DOE Office Websites (Extended Search)

AAI Homepage Lee Teng Scholarship Program USPAS Argonne Department of Education Fermilab Education Office For Students Many scientific advances are made using accelerators. The world of High Energy Particle Physics has driven this field and continues to depend largely on accelerators. Increasingly advances in materials science, chemistry, biology and environmental science are being made at accelerators using x-ray and neutrons to probe matter. Accelerators have a number of commercial applications including isotope production for use in medicine, cancer treatment, processing semiconductor chips, and so on. Presently there are around 15,000 accelerators worldwide. Approximately 97% of these are used for commercial applications. However several hundred are in use

364

Argonne Accelerator Institute  

NLE Websites -- All DOE Office Websites (Extended Search)

Mission Mission The mission of the Argonne Accelerator Institute is centered upon the following related goals: Locate next generation accelerator facilities in Northern Illinois Advance accelerator technology Oversee a selected, strategic, lab-wide, and acclaimed accelerator R&D portfolio In order to accomplish the above goals, the institute has established five objectives. These are coupled to programmatic objectives, and are dependent on each other, but they serve to identify important areas for the institute to focus its activities. Educate the "next generation" of accelerator physicists and engineers Work with area Universities to establish Joint Appointments and Adjunct Professorships Identify students Provide research opportunities at Argonne Work with the US Particle Accelerator School

365

BNL | Accelerator Test Facility  

NLE Websites -- All DOE Office Websites (Extended Search)

Accelerator Test Facility Accelerator Test Facility Home Core Capabilities Photoinjector S-Band Linac Laser Systems CO2 Laser Nd:Yag Laser Beamlines Beamline Simulation Data Beamline Parameters Beam Diagnostics Detectors Beam Schedule Operations Resources Fact Sheet (.pdf) Image Library Upgrade Proposal (.pdf) Publications ES&H Experiment Start-up ATF Handbook Laser Safety Collider-Accelerator Dept. C-AD ES&H Resources Staff Users' Place Apply for Access ATF photo ATF photo ATF photo ATF photo ATF photo A user facility for advanced accelerator research The Brookhaven Accelerator Test Facility (ATF) is a proposal driven, steering committee reviewed facility that provides users with high-brightness electron- and laser-beams. The ATF pioneered the concept of a user facility for studying complex properties of modern accelerators and

366

Argonne Accelerator Institute  

NLE Websites -- All DOE Office Websites (Extended Search)

Welcome Welcome In 2006, Argonne laboratory director Robert Rosner formed the AAI as a focal point for accelerator initiatives. The institute works to utilize Argonne's extensive accelerator resources, to enhance existing facilities, to determine the future of accelerator development and construction, and to oversee a dynamic and acclaimed accelerator physics portfolio. I invite you to look around the content of this web site. Accelerators at Argonne describes our rich heritage in this field, particularly with respect to the development and support of user facilities. Initiatives describes the things we are hoping to do, and Research & Development discusses our research portfolio. If you are a graduate or undergraduate student wishing to pursue a career in accelerator science or technology, please see Educational

367

North Linear Accelerator  

NLE Websites -- All DOE Office Websites (Extended Search)

North Linear Accelerator North Linear Accelerator Building Exterior Beam Enclosure Level Walk to the North Spreader North Recombiner Extras! North Linear Accelerator The North Linear Accelerator is one of the two long, straight sections of Jefferson Lab's accelerator. Electrons gain energy in this section by passing through acceleration cavities. There are 160 cavities in this straightaway, all lined up end to end. That's enough cavities to increase an electron's energy by 400 million volts each time it passes through this section. Electrons can pass though this section as many as five times! The cavities are powered by microwaves that travel down the skinny rectangular pipes from the service buildings above ground. Since the cavities won't work right unless they are kept very cold, they

368

Argonne Accelerator Institute  

NLE Websites -- All DOE Office Websites (Extended Search)

The Argonne Accelerator History Document Collection The Argonne Accelerator History Document Collection The Argonne Accelerator Institute (AAI) has established a special collection of archived documents which describe notable Argonne accelerator work of the past 50 years. A list of such Argonne Accelerator Projects is given below. Each project is described briefly, with links to archived documents in this collection. This collection includes important Argonne accelerator documents which may have become difficult to locate, as well as ones which have broad scope. In keeping with its historical purpose, this collection only covers work done 10 or more years ago. Many of the listed documents are available online. We hope to make more of them available online in the future. [For several of the projects, interesting additional online documents can be found by

369

Miniaturization Techniques for Accelerators  

SciTech Connect

The possibility of laser driven accelerators [1] suggests the need for new structures based on micromachining and integrated circuit technology because of the comparable scales. Thus, we are exploring fully integrated structures including sources, optics (for both light and particle) and acceleration in a common format--an accelerator-on-chip (AOC). Tests suggest a number of preferred materials and techniques but no technical or fundamental roadblocks at scales of order 1 {micro}m or larger.

Spencer, James E.

2003-05-27T23:59:59.000Z

370

Optically pulsed electron accelerator  

DOE Patents (OSTI)

An optically pulsed electron accelerator can be used as an injector for a free electron laser and comprises a pulsed light source, such as a laser, for providing discrete incident light pulses. A photoemissive electron source emits electron bursts having the same duration as the incident light pulses when impinged upon by same. The photoemissive electron source is located on an inside wall of a radiofrequency-powered accelerator cell which accelerates the electron burst emitted by the photoemissive electron source.

Fraser, J.S.; Sheffield, R.L.

1985-05-20T23:59:59.000Z

371

Optically pulsed electron accelerator  

DOE Patents (OSTI)

An optically pulsed electron accelerator can be used as an injector for a free electron laser and comprises a pulsed light source, such as a laser, for providing discrete incident light pulses. A photoemissive electron source emits electron bursts having the same duration as the incident light pulses when impinged upon by same. The photoemissive electron source is located on an inside wall of a radio frequency powered accelerator cell which accelerates the electron burst emitted by the photoemissive electron source.

Fraser, John S. (Los Alamos, NM); Sheffield, Richard L. (Los Alamos, NM)

1987-01-01T23:59:59.000Z

372

Accelerated Testing Validation  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Accelerated Testing Validation Rangachary Mukundan (PI), Rodney Borup, John Davey, Roger Lujan Los Alamos National Laboratory Adam Z. Weber Lawrence Berkeley National Laboratory...

373

Market Acceleration (Fact Sheet)  

SciTech Connect

The fact sheet summarizes the goals and activities of the DOE Solar Energy Technologies Program efforts within its market acceleration subprogram.

Not Available

2010-09-01T23:59:59.000Z

374

Accelerated Molecular Dynamics Methods  

Energy.gov (U.S. Department of Energy (DOE))

This presentation on Accelerated Molecular Dynamics Methods was given at the DOE Theory Focus Session on Hydrogen Storage Materials on May 18, 2006.

375

Accelerator Test Facility  

NLE Websites -- All DOE Office Websites (Extended Search)

Director ATF, Accelerator External program committee W. Leemans, Chair M. Woodle Engineer Mechanical M. Montemagno Engineer Electrical I. Pogorelsky, Physicist, Laser P. Jacob...

376

Accelerators, Beams And Physical Review Special Topics - Accelerators And Beams  

SciTech Connect

Accelerator science and technology have evolved as accelerators became larger and important to a broad range of science. Physical Review Special Topics - Accelerators and Beams was established to serve the accelerator community as a timely, widely circulated, international journal covering the full breadth of accelerators and beams. The history of the journal and the innovations associated with it are reviewed.

Siemann, R.H.; /SLAC

2011-10-24T23:59:59.000Z

377

Acceleration Worksheet 8/24/2011 ACCELERATION WORKSHEET  

E-Print Network (OSTI)

Acceleration Worksheet 8/24/2011 ACCELERATION WORKSHEET College of Arts and Sciences Name _____________ TO _____________ month/year month/year II. I meet the requirements for acceleration under [fill out either a) or b;Acceleration Worksheet 8/24/2011 Acceleration 2011-2012 Courses of Study The faculty of the college desires

Davis, H. Floyd

378

Explain cosmic acceleration? First, correct Einstein  

E-Print Network (OSTI)

In creating his gravitational field equations Einstein unjustifiedly assumed that inertial mass, and its energy equivalent, is a source of gravity. Denying this assumption allows modifying the field equations to a form in which a positive cosmological constant appears as a uniform density of gravitationally repulsive matter. This repulsive matter is identified as the back sides of the 'drainholes' (called by some 'traversable wormholes') introduced by the author in 1973, which attract on the high, front sides and repel more strongly on the low, back sides. The field equations with a scalar field added produce cosmological models that 'bounce' off a positive minimum of the scale factor and accelerate throughout history. The 'dark drainholes' that radiate nothing visible are hypothesized to constitute the 'dark matter' inferred from observation, their excess of negative active mass over positive active mass driving the accelerating expansion. For a universe with spatial curvature zero, and the ratio of scale fa...

Ellis, H G

2006-01-01T23:59:59.000Z

379

Future Accelerators, Muon Colliders, and Neutrino Factories  

SciTech Connect

Particle physics is driven by five great topics. Neutrino oscillations and masses are now at the fore. The standard model with extensions to supersymmetry and a Higgs to generate mass explains much of the field. The origins of CP violation are not understood. The possibility of extra dimensions has raised tantalizing new questions. A fifth topic lurking in the background is the possibility of something totally different. Many of the questions raised by these topics require powerful new accelerators. It is not an overstatement to say that for some of the issues, the accelerator is almost the experiment. Indeed some of the questions require machines beyond our present capability. As this volume attests, there are parts of the particle physics program that have been significantly advanced without the use of accelerators such as the subject of neutrino oscillations and many aspects of the particle-cosmology interface. At this stage in the development of physics, both approaches are needed and important. This chapter first reviews the status of the great accelerator facilities now in operation or coming on within the decade. Next, midrange possibilities are discussed including linear colliders with the adjunct possibility of gamma-gamma colliders, muon colliders, with precursor neutrino factories, and very large hadron colliders. Finally visionary possibilities are considered including plasma and laser accelerators.

Richard A Carrigan, Jr.

2001-12-19T23:59:59.000Z

380

Chemical oxidation of tryptic digests to improve sequence coverage in peptide mass fingerprint protein identification  

E-Print Network (OSTI)

Peptide mass fingerprinting (PMF) of protein digests is a widely-accepted method for protein identification in MS-based proteomic studies. Matrix-assisted laser desorption/ionization mass spectrometry (MALDI) is the technique of choice in PMF...

Lucas, Jessica Elaine

2004-09-30T23:59:59.000Z

Note: This page contains sample records for the topic "accelerator mass spectrometry" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

Neutrino physics at accelerators  

E-Print Network (OSTI)

Present and future neutrino experiments at accelerators are mainly concerned with understanding the neutrino oscillation phenomenon and its implications. Here a brief account of neutrino oscillations is given together with a description of the supporting data. Some current and planned accelerator neutrino experiments are also explained.

Enrique Fernandez

2006-07-16T23:59:59.000Z

382

Safety of Accelerator Facilities  

Directives, Delegations, and Requirements

To establish accelerator-specific safety requirements which, when supplemented by other applicable safety and health requirements, will serve to prevent injuries and illnesses associated with Department of Energy (DOE) or National Nuclear Security Administration (NNSA) accelerator operations. Cancels DOE O 420.2. Canceled by DOE O 420.2B.

2001-01-08T23:59:59.000Z

383

Safety of Accelerator Facilities  

Directives, Delegations, and Requirements

To establish accelerator-specific safety requirements which, when supplemented by other applicable safety and health requirements, will serve to prevent injuries and illnesses associated with Department of Energy (DOE) or National Nuclear Security Administration (NNSA) accelerator operations. Cancels DOE O 420.2A. Certified 5-13-08. Canceled by DOE O 420.2C.

2004-07-23T23:59:59.000Z

384

Microscale acceleration history discriminators  

DOE Patents (OSTI)

A new class of micromechanical acceleration history discriminators is claimed. These discriminators allow the precise differentiation of a wide range of acceleration-time histories, thereby allowing adaptive events to be triggered in response to the severity (or lack thereof) of an external environment. Such devices have applications in airbag activation, and other safety and surety applications.

Polosky, Marc A. (Albuquerque, NM); Plummer, David W. (Albuquerque, NM)

2002-01-01T23:59:59.000Z

385

Safety of Accelerator Facilities  

Directives, Delegations, and Requirements

The order defines accelerators and establishes accelerator specific safety requirements and approval authorities which, when supplemented by other applicable safety and health requirements, promote safe operations to ensure protection of workers, the public, and the environment. Cancels DOE O 420.2B.

2011-07-21T23:59:59.000Z

386

Accelerators (4/5)  

ScienceCinema (OSTI)

1a) Introduction and motivation 1b) History and accelerator types 2) Transverse beam dynamics 3a) Longitudinal beam dynamics 3b) Figure of merit of a synchrotron/collider 3c) Beam control 4) Main limiting factors 5) Technical challenges Prerequisite knowledge: Previous knowledge of accelerators is not required.

None

2011-10-06T23:59:59.000Z

387

Accelerators (3/5)  

ScienceCinema (OSTI)

1a) Introduction and motivation 1b) History and accelerator types 2) Transverse beam dynamics 3a) Longitudinal beam dynamics 3b) Figure of merit of a synchrotron/collider 3c) Beam control 4) Main limiting factors 5) Technical challenges Prerequisite knowledge: Previous knowledge of accelerators is not required.

None

2011-10-06T23:59:59.000Z

388

Accelerator Modeling with MATLAB Accelerator Toolbox  

SciTech Connect

This paper introduces Accelerator Toolbox (AT)--a collection of tools to model storage rings and beam transport lines in the MATLAB environment. The objective is to illustrate the flexibility and efficiency of the AT-MATLAB framework. The paper discusses three examples of problems that are analyzed frequently in connection with ring-based synchrotron light sources.

Terebilo, Andrei

2002-08-21T23:59:59.000Z

389

Collider-Accelerator Department  

NLE Websites -- All DOE Office Websites (Extended Search)

RHIC Tunnel and Magnets RHIC Tunnel and Magnets RHIC Tunnel and Magnets AGS Tunnel and Magnets NSRL Beamline RF Kicker Snake 200-MeV LINAC AGS Cold Snake Magnet About the Collider-Accelerator Department The mission of the Collider-Accelerator Department is to develop, improve and operate the suite of particle / heavy ion accelerators used to carry out the program of accelerator-based experiments at BNL; to support the experimental program including design, construction and operation of the beam transports to the experiments plus support of detector and research needs of the experiments; to design and construct new accelerator facilities in support of the BNL and national missions. The C-A Department supports an international user community of over 1500 scientists. The department performs all these functions in an environmentally responsible and safe manner under a rigorous conduct of operations approach.

390

Recent results obtained by use of accelerators on plasma-edge properties in controlled-fusion devices and on properties of high-power neutral beams  

SciTech Connect

The study of plasma-wall interactions is of primary importance in present fusion devices. Measurements of incident fuel and impurity fluxes, retention and release of fuel atoms, and erosion of internal components are of particular interest. Accelerators in the megaelectronvolt range are being used both to measure the depth profile of fuel atoms implanted in samples placed in the plasma edge by use of nuclear reactions and to measure impurities and film thicknesses by use of elastic scattering reactions. Secondary ion mass spectrometry (SIMS) is used to determine flux and energy distributions of fuel atoms and to measure species composition and impurities in the beams of high power neutral beam injectors. Recent results obtained with these techniques are presented and areas of future study are discussed.

Langley, R.A.

1982-01-01T23:59:59.000Z

391

Mass Spectrometry and Density Functional Theory Characterizations of DNA Modifications  

E-Print Network (OSTI)

to fully characterize synthetic DNA bearing cisplatin cross-in the hydrolysis of synthetic DNA as part of the MS-basedlink yield from synthetic DNA harboring 5-X-pyrimidines,

Williams, Renee Therese

2012-01-01T23:59:59.000Z

392

Mass Spectrometry and Density Functional Theory Characterizations of DNA Modifications  

E-Print Network (OSTI)

link yield from synthetic DNA harboring 5-X-pyrimidines,dU- and Br dC-containing synthetic DNA were reported, it wasthe phosphoramidites into synthetic DNA at a 5’-CpG-3’ site;

Williams, Renee Therese

2012-01-01T23:59:59.000Z

393

Ambient Sampling/Ionization Mass Spectrometry: Applications and Current Trends  

Science Journals Connector (OSTI)

drugs of abuse ... We felt that because ambient techniques are still young, fundamental studies are still critically needed to understand the range of applications that can be enabled by their use. ... The detection of counterfeit drugs is of particular interest since it is a growing issue in developing countries and over the Internet. ...

Glenn A. Harris; Asiri S. Galhena; Facundo M. Fernández

2011-04-15T23:59:59.000Z

394

Investigation of Metalloproteins Utilizing High Resolution Mass Spectrometry  

E-Print Network (OSTI)

.............................................................. 79 30 Fragment ion spectra of the [M+H]+ ions (a) Ac- Y(AEAAKA)2F-NH2 (-OCH3), (b) Ac-Y(AEAAKA)2F-NH2 (- 2OCH3) and (c) Ac-Y(AEAAKA)2F-NH2 (-3CH3)................. 82 31 Arrival time distribution (ATD) of the [M+H]+ ions of (a) Ac- Y...(AEAAKA)2F-NH2 (3OCH3) (FWHM:14), (b) Ac- Y(AEAAKA)2F-NH2 (2OCH3) (FWHM:25), (c) Ac- Y(AEAAKA)2F-NH2 (OCH3) (FWHM:21) and (d) Ac- Y(AEAAKA)2F-NH2 (FWHM:31)......................................... 85 32 Arrival time distribution (ATD) of the [M...

Wu, Zhaoxiang

2011-08-08T23:59:59.000Z

395

Environmental Mass Spectrometry: Emerging Contaminants and Current Issues  

Science Journals Connector (OSTI)

Alkylphenol ethoxylate surfactants are used heavily in the textile industry in pretreatment formulations and as additives in detergents or wetting agents for wool scouring, hydrogen peroxide bleaching, and dyeing. ...

Susan D. Richardson

2008-05-23T23:59:59.000Z

396

Extending the Capabilities of Single Particle Mass Spectrometry...  

NLE Websites -- All DOE Office Websites (Extended Search)

nm creating a distinct sharp feature on the small particle side 11 of the vacuum aerodynamic size distribution. Thus, the two quantities needed to determine 12 particle...

397

Site-specific analysis of glycosylated proteins using mass spectrometry  

E-Print Network (OSTI)

principle of ion cyclotron resonance (ICR)……….12 1.2.3 Ion injection into ICR…………………………………………….14 1.2.4 Ion trapping in the ICR…………………………………………..16 1.2.5 Ions excitation and detection in FTICR………………………17 1.3 MS/MS experiments... tension of the liquid, the liquid droplet explodes into smaller droplets containing an excess of positive charges as shown in Figure 1-2. 15 Once the charged droplet is formed, evaporation of the solvent is attained through application of heated...

Irungu, Janet W.

2008-01-16T23:59:59.000Z

398

Review of Mass Spectrometry–Based Metabolomics in Cancer Research  

Science Journals Connector (OSTI)

...potential future applications. Materials and Methods Identification...Administrative, technical, or material support (i.e., reporting...the studies reviewed: Pie diagrams including numbers and percentages...L-EDA in metabonomics data handling: Global metabolite profiling...

David B. Liesenfeld; Nina Habermann; Robert W. Owen; Augustin Scalbert; and Cornelia M. Ulrich

2013-12-01T23:59:59.000Z

399

Characterization of Bacteria by Particle Beam Mass Spectrometry  

Science Journals Connector (OSTI)

...of complex biological material is that of Meuzelaar...instrument, bulk samples of material (>10 Kg) are pyrolyzed...with minimal sample handling, from a naturally occurring...naires Disease (10). MATERIALS AND METHODS Bacteria...FIG. 1. Schematic diagram of particle beam MS...

Mahadeva P. Sinha; Robert M. Platz; Sheldon K. Friedlander; Vincent L. Vilker

1985-06-01T23:59:59.000Z

400

Mass Spectrometry and Density Functional Theory Characterizations of DNA Modifications  

E-Print Network (OSTI)

alkaline phosphatase (CIP). We chose Incorporation of DNADigestion NP1, exoPII, CIP, exoPI + Internal Standard Enzymethe addition of exoPI and CIP. Similar to NPI, exoPI creates

Williams, Renee Therese

2012-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "accelerator mass spectrometry" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Alternate Methods of Sample Introduction for Plasma Mass Spectrometry  

Science Journals Connector (OSTI)

......usually operated at 27.1 MHz. Plasmas such as these were first...species from matrix elements, plasma gases, atmospheric gases, or a combination...is not as severe with an atmospheric pressure plasma. Although a majority of......

J.M. Carey; F.A. Byrdy; J.A. Caruso

1993-08-01T23:59:59.000Z

402

Plasma desorption mass spectrometry of organics at low temperatures  

E-Print Network (OSTI)

The desorption/ionization of volatile hydrocarbons by Plasma Desorption (PD) produces a series of molecular ions. Among these are deprotonated molecular ions, which are not usually observed in PD. The H-loss phenomenon was examined as a function...

Shirey, Eldon Lynn

1993-01-01T23:59:59.000Z

403

Defining the Role of Mass Spectrometry in Cancer Diagnostics  

Science Journals Connector (OSTI)

...concentration of individual proteins. Although automation of the standard practice of selective...research. This point has been driven home again and again in the past as promising...samples simultaneously, the development of automation via robotics has descended on the sample...

O. John Semmes

2004-10-01T23:59:59.000Z

404

Algorithms for tandem mass spectrometry-based proteomics  

E-Print Network (OSTI)

By restricting this advanced search to the set of unidenti?require time-consuming advanced search techniques. Insteadimplementation of the advanced database searches such as the

Frank, Ari Michael

2008-01-01T23:59:59.000Z

405

Quantitative analysis of amino acid mixtures by mass spectrometry  

E-Print Network (OSTI)

trii&is' ir, il f actor to a deer?a'e iri . ,eii iLivt ty. Tlic v ir i sl iors i;s ner~si? I ivity diirirss1 a rii:i c, in i&e corrcciccl I r-orss I l, c cnanr, cs in the ?ieights of t he I'itK pe, iks. l' rrsigt. r ? e arJc'? I that the I risrrumc...:. pool&lc:r;i. T:ie 1ix1 t of cl?i ceil. i osi wor? sio L iles & sii I ? I iy?u? tablish?i' in Ll, ? c irr?" L work. llew?ver s ciili, r L o, , ciir. ve - w?co lirieii; I, ir oi&illi Li, ? rii, ii. en coi. . i dere?. Ti ? sels. i Livit y 1 or eacs...

Bird, James Spencer

2012-06-07T23:59:59.000Z

406

Recovering Sparse Low-rank Blocks in Tandem Mass Spectrometry  

E-Print Network (OSTI)

, Pedro Navarro2, and Richard G. Baraniuk1 1 Rice University, Houston, TX, USA; e-mail: {studer, richb}@rice.edu 2 ETH Z¨urich, Z¨urich, Switzerland; e-mail: graemepope@gmail.com, navarro

407

DEDICATED HEAVY ION MEDICAL ACCELERATORS  

E-Print Network (OSTI)

Lancaster, R.B. Yourd, Pre~,Accelerator A w·ideroe~,Basedcarbon beam medical accelerator facility. N "' . ,;j "' ::lEat the MARIA Workshop III: Accelerator Systems for Relat ic

Gough, R.A.

2013-01-01T23:59:59.000Z

408

History of Proton Linear Accelerators  

E-Print Network (OSTI)

the board to show why the accelerator couldn't work. Then atmuch. References 1. Linear Accelerators, edited by P. M .at the 1986 Linear Accelerator Conference, SLAC, Stanford,

Alvarez, Luis W.

1986-01-01T23:59:59.000Z

409

Accelerated Least Squares Multidimensional Scaling  

E-Print Network (OSTI)

x(make_x(36,2)) xACCELERATED SCALING R EFERENCES I.ACCELERATED LEAST SQUARES MULTIDIMENSIONAL SCALING JAN DEare simpler to write. ACCELERATED SCALING It is shown in De

Leeuw, Jan de

2006-01-01T23:59:59.000Z

410

Accelerated Least Squares Multidimensional Scaling  

E-Print Network (OSTI)

x(make_x(36,2)) xACCELERATED SCALING R EFERENCES I.ACCELERATED LEAST SQUARES MULTIDIMENSIONAL SCALING JAN DEare simpler to write. ACCELERATED SCALING It is shown in De

Jan de Leeuw

2011-01-01T23:59:59.000Z

411

Accelerator Physics and Design at NERSC  

NLE Websites -- All DOE Office Websites (Extended Search)

Accelerator Science Accelerator Science ReframAccelerator.jpg Particle accelerators are among the largest, most complex, and most important scientific instruments in the world....

412

Computational studies and optimization of wakefield accelerators  

E-Print Network (OSTI)

optimization of wakefield accelerators C. G. R. Geddes 1 ,from the U.S. -LHC Accelerator Research Program (LARP),driven plasma wakefield accelerators produce accelerating

Geddes, C.G.R.

2010-01-01T23:59:59.000Z

413

Argonne Accelerator Institute  

NLE Websites -- All DOE Office Websites (Extended Search)

AAI Home AAI Home Welcome Accelerators at Argonne Mission Organization History Document Collection Conferences & Workshops Beams and Applications Seminar Argonne-Fermilab Collaboration Lee Teng Scholarship Program Useful Links Organization The Argonne Accelerator Institute is a matrixed organization. Its members and fellows reside in programmatic Argonne divisions. The Institute reports to the Associate Laboratory Director for Photon Science), and the administrative functions of the Institute are within the PSC directorate. Director: Rodney Gerig Associate Director: Hendrik Weerts ( Director of High Energy Physics Division) Associate Director: Sasha Zholents (Director of Accelerator Systems Division) Associate Director: Robert Janssens ( Director of Argonne Physics Division)

414

Accelerator Toolbox for MATLAB  

SciTech Connect

This paper introduces Accelerator Toolbox (AT)--a collection of tools to model particle accelerators and beam transport lines in the MATLAB environment. At SSRL, it has become the modeling code of choice for the ongoing design and future operation of the SPEAR 3 synchrotron light source. AT was designed to take advantage of power and simplicity of MATLAB--commercially developed environment for technical computing and visualization. Many examples in this paper illustrate the advantages of the AT approach and contrast it with existing accelerator code frameworks.

Terebilo, Andrei

2001-05-29T23:59:59.000Z

415

C-AD Accelerator Division  

NLE Websites -- All DOE Office Websites (Extended Search)

Accelerator Division Accelerator Division The Accelerator Division operates and continually upgrades a complex of eight accelerators: 2 Tandem Van de Graaff electrostatic accelerators, an Electron Beam Ion Source (EBIS), a 200 MeV proton Linac, the AGS Booster, the Alternating Gradient Synchrotron (AGS), and the 2 rings of the Relativistic Heavy Ion Collider (RHIC). These machines serve user programs at the Tandems, the Brookhaven Linac Isotope Producer (BLIP), the NASA Space Radiation Laboratory (NSRL), and the 2 RHIC experiments STAR, and PHENIX. The Division also supports the development of new accelerators and accelerator components. Contact Personnel Division Head: Wolfram Fischer Deputy Head: Joe Tuozzolo Division Secretary: Anna Petway Accelerator Physics: Michael Blaskiewicz

416

Argonne Accelerator Institute  

NLE Websites -- All DOE Office Websites (Extended Search)

Quarterly Meetings Quarterly Meetings November 29, 2011 Held at the Advanced Photon Source, Argonne, IL DOE Accelerator R&D Task Force - M. White February 17, 2010 Held at the Advanced Photon Source, Argonne, IL June 16, 2009 General Updates - R. Gerig Accelerator Developments in Physics Division - R. Janssens Proposal for Argonne SRF Facility - M. Kelly Accelerator Developments in HEP Division - W. Gai Beam Activities of the DOD Project Office-Focus on the Navy FEL - S. Biedron AAI Historical Collection - T. Fields November 24, 2008 Strategic Theme Forum Meeting - This meeting was held to gather information on the Accelerator Science and Technology Theme to establish the Argonne's Strategic Plan January 9, 2008 Opening Remarks - R. Gerig ILC Planning - J. Carwardine Argonne Participation in Project X - P. Ostroumov

417

Advanced Accelerator Concepts Workshop  

NLE Websites -- All DOE Office Websites (Extended Search)

acceleration at the BNL-ATF Thomas Marshall GeVm WAKE FIELDS GENERATED BY A TRAIN OF pC, FEMTOSECOND BUNCHES IN A PLANAR DIELECTRIC MICROSTRUCTURE Changbiao Wang GeVm...

418

Accelerated Currents in Superconductors  

Science Journals Connector (OSTI)

It is shown that the ratio of the accelerated currents of energy and matter induced in a superconductor by a long-wavelength electric field is equal to the chemical potential of the system.

Vinay Ambegaokar and Gerald Rickayzen

1966-02-04T23:59:59.000Z

419

Accelerator on a Chip  

ScienceCinema (OSTI)

SLAC's Joel England explains how the same fabrication techniques used for silicon computer microchips allowed their team to create the new laser-driven particle accelerator chips. (SLAC Multimedia Communications)

England, Joel

2014-07-16T23:59:59.000Z

420

Accelerator on a Chip  

SciTech Connect

SLAC's Joel England explains how the same fabrication techniques used for silicon computer microchips allowed their team to create the new laser-driven particle accelerator chips. (SLAC Multimedia Communications)

England, Joel

2014-06-30T23:59:59.000Z

Note: This page contains sample records for the topic "accelerator mass spectrometry" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

Advanced Accelerator Concepts Workshop  

NLE Websites -- All DOE Office Websites (Extended Search)

EM Structure-Based Accelerators Working Group Group-Leader: Wayne Kimura, STI Optronics (wkimura@stioptronics.com) Group-Co-leader: Steve Lidia, LBNL (SMLidia@lbl.gov)...

422

CEBAF accelerator achievements  

SciTech Connect

In the past decade, nuclear physics users of Jefferson Lab's Continuous Electron Beam Accelerator Facility (CEBAF) have benefited from accelerator physics advances and machine improvements. As of early 2011, CEBAF operates routinely at 6 GeV, with a 12 GeV upgrade underway. This article reports highlights of CEBAF's scientific and technological evolution in the areas of cryomodule refurbishment, RF control, polarized source development, beam transport for parity experiments, magnets and hysteresis handling, beam breakup, and helium refrigerator operational optimization.

Y.C. Chao, M. Drury, C. Hovater, A. Hutton, G.A. Krafft, M. Poelker, C. Reece, M. Tiefenback

2011-06-01T23:59:59.000Z

423

Decay of accelerated particles  

Science Journals Connector (OSTI)

We study how the decay properties of particles are changed by acceleration. It is shown that under the influence of acceleration (1) the lifetime of particles is modified and (2) new processes (such as the decay of the proton) become possible. This is illustrated by considering scalar models for the decay of muons, pions, and protons. We discuss the close conceptual relation between these processes and the Unruh effect.

Rainer Müller

1997-07-15T23:59:59.000Z

424

Breakthrough: Fermilab Accelerator Technology  

SciTech Connect

There are more than 30,000 particle accelerators in operation around the world. At Fermilab, scientists are collaborating with other laboratories and industry to optimize the manufacturing processes for a new type of powerful accelerator that uses superconducting niobium cavities. Experimenting with unique polishing materials, a Fermilab team has now developed an efficient and environmentally friendly way of creating cavities that can propel particles with more than 30 million volts per meter.

None

2012-04-23T23:59:59.000Z

425

Breakthrough: Fermilab Accelerator Technology  

ScienceCinema (OSTI)

There are more than 30,000 particle accelerators in operation around the world. At Fermilab, scientists are collaborating with other laboratories and industry to optimize the manufacturing processes for a new type of powerful accelerator that uses superconducting niobium cavities. Experimenting with unique polishing materials, a Fermilab team has now developed an efficient and environmentally friendly way of creating cavities that can propel particles with more than 30 million volts per meter.

None

2014-08-12T23:59:59.000Z

426

Advanced accelerator simulation research: miniaturizing accelerators from kilometers to meters  

E-Print Network (OSTI)

Advanced accelerator simulation research: miniaturizing accelerators from kilometers to meters W: Advanced accelerator research is aimed at finding new technologies that can dramatically reduce the size and cost of future high-energy accelerators. Supercomputing is already playing a dramatic and critical role

Geddes, Cameron Guy Robinson

427

ACCELERATED IMPROVEMENT A CONCENTRATED APPROACH  

E-Print Network (OSTI)

ACCELERATED IMPROVEMENT A CONCENTRATED APPROACH FOR CONTINUOUS IMPROVEMENT #12;Accelerated.quality.wisc.edu O F F I C E O F Q U A L I T Y I M P R O V E M E N T Accelerated Improvement This guide to improving resources. You will find helpful information needed to conduct an Accelerated Improvement project

Shapiro, Vadim

428

US LHC Accelerator Research Program  

E-Print Network (OSTI)

US LHC Accelerator Research Program Instrumentation Collaboration Meeting John Marriner May 9, 2003 #12;2/14/03 US LARP Instrumentation Collaboration Mtg 2 US LARP LARP = LHC Accelerator Research Program LARP is an outgrowth of the US LHC Accelerator Project The US LHC Accelerator Project built

Large Hadron Collider Program

429

Determination of boron isotope ratios by Zeeman effect background correction-graphite furnace atomic absorption spectrometry  

Science Journals Connector (OSTI)

A new method for the determination of isotopic ratio of boron using Zeeman effect background correction-graphite furnace atomic absorption spectrometry with conventional atomizer and natural-boron hollow cathode source is described. The isotope-shift Zeeman effect at 208.9 nm is utilized for isotopic ratio determination. At a given concentration of total boron, the net absorbance decreases linearly with increasing 10B/11B ratio. The absorbances are recorded at the field strength of 1.0 T. The isotope ratios measured by the proposed method were in good agreement with the results obtained by inductively coupled plasma-quadruple mass spectrometry or thermal ionization mass spectrometry. The present method is fairly fast and less expensive compared to the above techniques and is quite suitable for plant environments.

S. Thangavel; S.V. Rao; K. Dash; J. Arunachalam

2006-01-01T23:59:59.000Z

430

Advection of surface-derived organic carbon fuels microbial reduction in Bangladesh groundwater  

Science Journals Connector (OSTI)

...since atmospheric testing of nuclear bombs began in the 1950s...National Ocean Sciences Accelerator Mass Spectrometry Facility...presented with the reported accelerator mass spectrometry...cycle 70 followed by repeated vacuum infiltration. Lysozyme...

Brian J. Mailloux; Elizabeth Trembath-Reichert; Jennifer Cheung; Marlena Watson; Martin Stute; Greg A. Freyer; Andrew S. Ferguson; Kazi Matin Ahmed; Md. Jahangir Alam; Bruce A. Buchholz; James Thomas; Alice C. Layton; Yan Zheng; Benjamin C. Bostick; Alexander van Geen

2013-01-01T23:59:59.000Z

431

Optical and Mass Spectrometric Studies of a Helium Dielectric-Barrier Atmospheric-Pressure Plasma Jet Used as an Ambient Desorption Ionization Source.  

E-Print Network (OSTI)

??Recently there has been a surge in the field of mass spectrometry centered around the concept of rapid analysis of target analytes with minimal or… (more)

Heywood, Matthew Spencer

2012-01-01T23:59:59.000Z

432

Fission product studies in the symmetric mass region  

SciTech Connect

Fission yields can be determined by radiochemical or mass spectrometric techniques. Mass spectrometry can provide more accurate data, particularly in the symmetric mass region where the probability of fission is low and uncertainties in isometric ratios occur. Fine structure in the mass distribution can usually only be determined by mass spectrometry. Many of the elements in the valley of symmetry have high ionization potentials and are therefore difficult to measure by solid source mass spectrometry. Analytical techniques have been developed to provide the sensitivity required to measure the small sample sizes available in fission product studies. Cumulative fission yields for ruthenium, palladium, cadmium, tin, and tellurium have been measured by mass spectrometry for the thermal and epicadmium fission of {sup 233}U and for thermal and epicadmium fission of {sup 239}Pu. These fission yields, which span the mass range 101 {le} A {le} 130, can be combined to give a mass yield curve for {sup 235}U in the valley region, which is symmetrical about A = 116.8 and exhibits fine structure in the mass 113 to 114 region. Fine structure in {sup 233}U is also present at mass 111. Mass spectrometric determinations of the fission yields of uranium ore at the Oklo mine site in Gabon enable the nuclear parameters of this natural reactor to be evaluated. This in turn enables the amounts of fission products produced in the reactor zone and the surrounding rocks enables an assessment to be made of the efficiency of this geological repository for containing radioactive waste. The elemental abundances can be determined by isotope dilution mass spectrometry. Unfortunately, the paucity of good fission yield data available for {sup 238}U by fast neutrons is a severe constraint in this evaluation.

De Laeter, J.R.; Rosman, K.J.R.; Loss, R.D. [Curtin Univ. of Technology, Perth (AU)

1993-05-01T23:59:59.000Z

433

Stable Isotope, Site-Specific Mass Tagging For Protein Identification  

NLE Websites -- All DOE Office Websites (Extended Search)

Stable Isotope, Site-Specific Mass Tagging For Protein Stable Isotope, Site-Specific Mass Tagging For Protein Identification Stable Isotope, Site-Specific Mass Tagging For Protein Identification Proteolytic peptide mass mapping as measured by mass spectrometry provides an important method for the identification of proteins, which are usually identified by matching the measured and calculated m/z values of the proteolytic peptides. Available for thumbnail of Feynman Center (505) 665-9090 Email Stable Isotope, Site-Specific Mass Tagging For Protein Identification Proteolytic peptide mass mapping as measured by mass spectrometry provides an important method for the identification of proteins, which are usually identified by matching the measured and calculated m/z values of the proteolytic peptides. A unique identification is, however, heavily

434

BNL | Our History: Accelerators  

NLE Websites -- All DOE Office Websites (Extended Search)

> See also: Reactors > See also: Reactors A History of Leadership in Particle Accelerator Design Cosmotron Cosmotron (1952-1966) Early in Brookhaven Lab history, the consortium of universities responsible for founding the new research center, decided that Brookhaven should provide leading facilities for high energy physics research. In April 1948, the Atomic Energy Commission approved a plan for a proton synchrotron to be built at Brookhaven. The new machine would accelerate protons to previously unheard of energies-comparable to the cosmic rays showering the earth's outer atmosphere. It would be called the Cosmotron. The Cosmotron was the first accelerator in the world to send particles to energies in the billion electron volt, or GeV, region. The machine reached its full design energy of 3.3 GeV in 1953.

435

Accelerator Update | Archive | 2012  

NLE Websites -- All DOE Office Websites (Extended Search)

2 Accelerator Update Archive 2 Accelerator Update Archive April 27, 2012 - April 30, 2012 NuMI reported receiving 7.67E18 protons on target for the period from 4/23/12 to 4/30/12. The Booster developed an aperture restriction that required lower beam intensity Main Injector personnel completed their last study The shutdown begins Linac, MTA, and Booster will continue using beam for one or two more weeks Linac will supply the Neutron Therapy Facility beam for most of the shutdown April 25, 2012 - April 27, 2012 Booster beam stop problem repaired Beam to all experiments will shut off at midnight on Monday morning, 4/30/12. Main Injector will continue to take beam until 6 AM on Monday morning. Linac, the Neutron Therapy Facility, MTA, and Booster will continue using beam for one or two more weeks. The Fermi Accelerator Complex will be in shutdown for approximately one year

436

ORELA accelerator facility  

NLE Websites -- All DOE Office Websites (Extended Search)

The Oak Ridge Electron Linear Accelerator The Oak Ridge Electron Linear Accelerator Pulsed Neutron Source The ORELA is a powerful electron accelerator-based neutron source located in the Physics Division of Oak Ridge National Laboratory. It produces intense, nanosecond bursts of neutrons, each burst containing neutrons with energies from 10e-03 to 10e08 eV. ORELA is operated about 1200 hours per year and is an ORNL User Facility open to university, national laboratory and industrial scientists. The mission of ORELA has changed from a recent focus on applied research to nuclear astrophysics. This is an area in which ORELA has historically been very productive: most of the measurements of neutron capture cross sections necessary for understanding heavy element nucleosynthesis through the slow neutron capture process (s-process) have

437

Improving Alpha Spectrometry Energy Resolution by Ion Implantation with ICP-MS  

SciTech Connect

We report results of a novel technique using an Inductively Coupled Plasma Mass Spectrometer (ICP-MS) as a method of source preparation for alpha spectrometry. This method produced thin, contaminant free 241Am samples which yielded extraordinary energy resolution which appear to be at the lower limit of the detection technology used in this research.

Dion, Michael P.; Liezers, Martin; Farmer, Orville T.; Miller, Brian W.; Morley, Shannon M.; Barinaga, Charles J.; Eiden, Gregory C.

2015-01-01T23:59:59.000Z

438

Cadmium measurements in coral skeleton using isotope dilutioninductively coupled plasmamass spectrometry  

E-Print Network (OSTI)

of pollution in corals growing near industri- al/urban sites where Cd concentrations can be 10 times higher­mass spectrometry Kathryn A. Matthews Department of Earth and Environmental Science, University of Pennsylvania, 240 skeleton to construct records of the frequency and intensity of oceanic upwelling. During upwelling

Mcdonough, William F.

439

Interfacing to accelerator instrumentation  

SciTech Connect

As the sensory system for an accelerator, the beam instrumentation provides a tremendous amount of diagnostic information. Access to this information can vary from periodic spot checks by operators to high bandwidth data acquisition during studies. In this paper, example applications will illustrate the requirements on interfaces between the control system and the instrumentation hardware. A survey of the major accelerator facilities will identify the most popular interface standards. The impact of developments such as isochronous protocols and embedded digital signal processing will also be discussed.

Shea, T.J.

1995-12-31T23:59:59.000Z

440

Perimeter Institute Cosmic Acceleration  

E-Print Network (OSTI)

Wayne Hu Perimeter Institute April 2010 Cosmic Acceleration Dark Energy v. Modified Gravity #12;Outline · Dark Energy vs Modified Gravity · Three Regimes of Modified Gravity · Worked (Toy) Models: f 1998 Discovery #12;Mercury or Pluto? General relativity says Gravity = Geometry And Geometry = Matter-Energy

Hu, Wayne

Note: This page contains sample records for the topic "accelerator mass spectrometry" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

Accelerating News Issue 5  

E-Print Network (OSTI)

In this spring issue, we look at developments towards higher luminosity and higher energy colliders. We report on the technology developed for the remote powering of the LHC magnets and studies of diagnostics based on higher order mode port signals. We also inform you about the main outcome of the TIARA survey on market needs for accelerator scientists.

Szeberenyi, A

2013-01-01T23:59:59.000Z

442

Note on accelerated detectors  

Science Journals Connector (OSTI)

The Unruh result, on the thermal-like behavior of particle detectors under a uniformly accelerated state of motion, is found by a different method which does not involve field quantization in a metric with a horizon. The result is extended to other situations.

P. Meyer

1978-07-15T23:59:59.000Z

443

Acceleration of Time Integration  

SciTech Connect

We outline our strategies for accelerating time integration for long-running simulations, such as those for global climate modeling. The strategies target the Cray XT systems at the National Center for Computational Sciences at Oak Ridge National Laboratory. Our strategies include fully implicit, parallel-in-time, and curvelet methods.

White III, James B [ORNL; Drake, John B [ORNL; Worley, Patrick H [ORNL; Archibald, Richard K [ORNL; Evans, Katherine J [ORNL; Kothe, Douglas B [ORNL

2007-01-01T23:59:59.000Z

444

ELECTRON INJECTION INTO CYCLIC ACCELERATOR USING  

E-Print Network (OSTI)

ELECTRON INJECTION INTO CYCLIC ACCELERATOR USING LASER WAKEFIELD ACCELERATION Ya. V. Getmanov, O. A acceleration #12;Storage ring with laser injection CYCLIC ACCELERATOR RF Electron injection The LWFA beam ­ accelerating light, 5 ­ accelerated electrons, 6 ­fast kicker - + accelerating laser pulse evaporatinglaser

445

Acceleration and Classical Electromagnetic Radiation  

E-Print Network (OSTI)

Classical radiation from an accelerated charge is reviewed along with the reciprocal topic of accelerated observers detecting radiation from a static charge. This review commemerates Bahram Mashhoon's 60th birthday.

E. N. Glass

2008-01-09T23:59:59.000Z

446

Laser Wakefield Particle Accelerators Project at NERSC  

NLE Websites -- All DOE Office Websites (Extended Search)

Laser Wakefield Particle Acceleration Laser Wakefield Particle Acceleration Vorpal.jpg Key Challenges: Design of multiple-staged, 10-GeV laser-wakefield plasma accelerated...

447

Charge Diagnostics for Laser Plasma Accelerators  

E-Print Network (OSTI)

the 1989 Particle Accelerator Conference, IEEE, Piscataway,Diagnostics for Laser Plasma Accelerators K . Nakamura, A .ALS) synchrotron booster accelerator. The sensitivity of the

Nakamura, K.

2011-01-01T23:59:59.000Z

448

Fermilab | Science | Particle Accelerators | Advanced Superconducting...  

NLE Websites -- All DOE Office Websites (Extended Search)

Superconducting Test Accelerator is America's only test bed for cutting-edge particle beams and for accelerator research aimed at Intensity Frontier proton accelerators. ASTA...

449

History of Proton Linear Accelerators  

DOE R&D Accomplishments (OSTI)

Some personal recollections are presented that relate to the author`s experience developing linear accelerators, particularly for protons. (LEW)

Alvarez, L. W.

1987-01-00T23:59:59.000Z

450

Acceleration in de Sitter spacetimes  

E-Print Network (OSTI)

We propose a definition of uniform accelerated frames in de Sitter spacetimes exploiting the Nachtmann group theoretical method of introducing coordinates on these manifolds. Requiring the transformation between the static frame and the accelerated one to depend continuously on acceleration in order to recover the well-known Rindler approach in the flat limit, we obtain a new metric with a reasonable physical meaning.

Ion I. Cotaescu

2014-07-09T23:59:59.000Z

451

Basic concepts in plasma accelerators  

Science Journals Connector (OSTI)

...plasma accelerators. Plasma accelerators are ideal...2. Relativistic plasma wave acceleration The...electric field at the focus of high-power short-pulse...Diffraction limits the depth of focus to the Rayleigh length...stimulated Brillouin and plasma modulational instabilities...

2006-01-01T23:59:59.000Z

452

Accelerator Update | Archive | 2010  

NLE Websites -- All DOE Office Websites (Extended Search)

10 Accelerator Update Archive 10 Accelerator Update Archive December 20, 2010 - December 22, 2010 - Three stores provided !32 hours of luminosity - Problems with two Linac quadrupole power supplies - Cryo system technicians work on TEV sector D1 wet engine - TEV quench during checkout - JASMIN's run at MTest ends December 17, 2010 - December 20, 2010 The Integrated Luminosity for the period from 12/13/10 to 12/20/10 was 66.31 inverse picobarns. NuMI reported receiving 7.62E18 protons on target during this same period. - Five Stores provided ~62 hours of luminosity - Operations had trouble with a Linac RF station (LRF3) - Operators tuned the Linac backup source (I- Source) December 15, 2010 - December 17, 2010 - Three stores provided ~36.1 hours of luminosity - MI-52 Septa repaired - NuMI recovered its target LCW system

453

ACCELERATOR SAFETY ENVELOPE  

NLE Websites -- All DOE Office Websites (Extended Search)

LCASE-001, Ver. 3 LCASE-001, Ver. 3 Linac Commissioning Accelerator Safety Envelope For the National Synchrotron Light Source II Photon Sciences Directorate Version 3 December 8, 2011 Prepared by Brookhaven National Laboratory P.O. Box 5000 Upton, NY 11973-5000 managed by Brookhaven Science Associates for the U.S. Department of Energy Office of Science Basic Energy Science under contract DE-AC02-98CD10886 Linac Commissioning Accelerator Safety Envelope (LCASE) ii Photon Sciences Directorate ii DISCLAIMER This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, nor any of their contractors, subcontractors, or their employees, makes any warranty,

454

Argonne Accelerator Institute  

NLE Websites -- All DOE Office Websites (Extended Search)

CWDD - Continuous Wave Deuterium Demonstrator CWDD - Continuous Wave Deuterium Demonstrator The Continuous Wave Deuterium Demonstrator (CWDD) accelerator, a cryogenically-cooled (26K) linac, was designed to accelerate 80 mA cw of D to 7.5 MeV. CWDD was being built to demonstrate the lauching of a beam with characteristics suitable for a space-based neutral particle-beam (NPB). A considerable amount of hardware was constructed and installed in the Argonne-based facility, and major performance milestones were achieved before program funding ended in October 1993. References - Document Access Guide Continuous Wave Deuterium Demonstrator Final Design Review, Grumman Space Systems, Grumman-Culham Laboratory, Los Alamos (1989). (Located in the Argonne Research Library) Recommissioning and first operation of the CWDD injector at Argonne

455

Accelerator Update | Archive | 2009  

NLE Websites -- All DOE Office Websites (Extended Search)

9 Accelerator Update Archive 9 Accelerator Update Archive December 18, 2009 - December 21, 2009 The integrated luminosity for the period from 12/14/09 to 12/21/09 was 51.27 inverse picobarns. NuMI reported receiving 6.38E18 protons on target during this same period. - Four stores provided ~62.25 hours of luminosity - Store 7444 had an AIL of 306E30 - BRF19 cavity suffered a vacuum failure and was removed - The Booster West Anode Power Supply suffered some problems December 16, 2009 - December 18, 2009 - Three stores provided ~45 hours of luminosity - PBar kicker problem - MI RF problems December 14, 2009 - December 16, 2009 - Four stores provided ~42 hours of luminosity - Recycler kicker repaired - Booster East Anode Power Supply trips due to BRF1, 2, & 8 December 11, 2009 - December 14, 2009

456

WIPP Accelerating Cleanup  

NLE Websites -- All DOE Office Websites (Extended Search)

ACCELERATING CLEANUP: ACCELERATING CLEANUP: PATHS TO CLOSURE CARLSBAD AREA OFFICE JUNE 1998 I. Operations/Field Overview CAO Mission The mission of the Carlsbad Area Office (CAO) is to protect human health and the environment by opening and operating the Waste Isolation Pilot Plant (WIPP) for safe disposal of transuranic (TRU) waste and by establishing an effective system for management of TRU waste from generation to disposal. It includes personnel assigned to CAO, WIPP site operations, transportation, and other activities associated with the National TRU Program (NTP). The CAO develops and directs implementation of the TRU waste program, and assesses compliance with the program guidance, as well as the commonality of activities and assumptions among all TRU waste sites. NTP Program Management

457

Plasma Wakefield Acceleration  

NLE Websites -- All DOE Office Websites (Extended Search)

rpwa rpwa Sign In Launch the Developer Dashboard SLAC National Accelerator Laboratory DOE | Stanford | SLAC | SSRL | LCLS | AD | PPA | Photon Science | PULSE | SIMES FACET User Facility : FACET An Office of Science User Facility Search this site... Search Help (new window) Top Link Bar FACET User Facility FACET Home About FACET FACET Experimental Facilities FACET Users Research at FACET SAREC Expand SAREC FACET FAQs FACET User Facility Quick Launch FACET Users Home FACET Division ARD Home About FACET FACET News FACET Users FACET Experimental Facilities FACET Research Expand FACET Research FACET Images Expand FACET Images SAREC Expand SAREC FACET Project Site (restricted) FACET FAQs FACET Site TOC All Site Content Department of Energy Page Content Plasma Wakefield Acceleration

458

Argonne Accelerator Institute  

NLE Websites -- All DOE Office Websites (Extended Search)

ZGS -- Zero Gradient Synchrotron (operation: 1963 - 1979) ZGS -- Zero Gradient Synchrotron (operation: 1963 - 1979) The ZGS was a 12 GeV weak-focusing proton synchrotron. It was the first high energy physics accelerator located between the U.S. coasts. The ZGS was also the first synchrotron to accelerate spin polarized protons and the first to use H-minus injection. Other noteworthy features of the ZGS program were the large number of university-based users and the pioneering development of large superconducting magnets for bubble chambers and beam transport. References - Document Access Guide History of the ZGS, Argonne, 1979, American Institute of Physics, AIP Conference Proceedings No. 60 (1980). (Located in the Argonne Research Library) High Energy Physics at Argonne National Laboratory, A. Crewe, R.

459

ACCELERATOR SAFETY ENVELOPE  

NLE Websites -- All DOE Office Websites (Extended Search)

BCASE-001, Ver. 2 BCASE-001, Ver. 2 Booster Commissioning Accelerator Safety Envelope For the National Synchrotron Light Source II Photon Sciences Directorate Version 2 December 8, 2011 Prepared by Brookhaven National Laboratory P.O. Box 5000 Upton, NY 11973-5000 managed by Brookhaven Science Associates for the U.S. Department of Energy Office of Science Basic Energy Science under contract DE-AC02-98CD10886 Booster Commissioning Accelerator Safety Envelope (BCASE) ii Photon Sciences Directorate ii DISCLAIMER This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, nor any of their contractors, subcontractors, or their employees, makes any warranty,

460

Radiation from accelerated branes  

Science Journals Connector (OSTI)

The radiation emitted by accelerated fundamental strings and D-branes is studied within the linear approximation to the supergravity limit of string theory. We show that scalar, gauge field and gravitational radiation is generically emitted by such branes. In the case where an external scalar field accelerates the branes, we derive a Larmor-type formula for the emitted scalar radiation and study the angular distribution of the outgoing energy flux. The classical radii of the branes are calculated by means of the corresponding Thompson scattering cross sections. Within the linear approximation, the interaction of the external scalar field with the velocity fields of the branes gives a contribution to the observed gauge field and gravitational radiation.

Mohab Abou-Zeid and Miguel S. Costa

2000-04-26T23:59:59.000Z

Note: This page contains sample records for the topic "accelerator mass spectrometry" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


461

Accelerators for Cancer Therapy  

DOE R&D Accomplishments (OSTI)

The vast majority of radiation treatments for cancerous tumors are given using electron linacs that provide both electrons and photons at several energies. Design and construction of these linacs are based on mature technology that is rapidly becoming more and more standardized and sophisticated. The use of hadrons such as neutrons, protons, alphas, or carbon, oxygen and neon ions is relatively new. Accelerators for hadron therapy are far from standardized, but the use of hadron therapy as an alternative to conventional radiation has led to significant improvements and refinements in conventional treatment techniques. This paper presents the rationale for radiation therapy, describes the accelerators used in conventional and hadron therapy, and outlines the issues that must still be resolved in the emerging field of hadron therapy.

Lennox, Arlene J.

2000-05-30T23:59:59.000Z

462

The Muon Accelerator Program  

SciTech Connect

Multi-TeV Muon Colliders and high intensity Neutrino Factories have captured the imagination of the particle physics community. These new types of facility both require an advanced muon source capable of producing O(10{sup 21}) muons per year. The muons must be captured within bunches, and their phase space manipulated so that they fit within the acceptance of an accelerator. In a Neutrino Factory (NF), muons from this 'front end' are accelerated to a few GeV or a few tens of GeV, and then injected into a storage ring with long straight sections. Muon decays in the straight sections produce an intense neutrino beam. In a Muon Collider (MC) the muons must be cooled by a factor O(10{sup 6}) to produce beams that are sufficiently bright to give high luminosity in the collider. Bunches of positive and negative muons are then accelerated to high energy, and injected in opposite directions into a collider ring in which they collide at one or more interaction points. Over the last decade our understanding of the concepts and technologies needed for Muon Colliders and Neutrino Factories has advanced, and it is now believed that, within a few years, with a well focused R&D effort (i) a Neutrino Factory could be proposed, and (ii) enough could be known about the technologies needed for a Muon Collider to assess the feasibility and cost of this new type of facility, and to make a detailed plan for the remaining R&D. Although these next NF and MC steps are achievable, they are also ambitious, and will require an efficient and dedicated organization to accomplish the desired goals with limited resources. The Muon Accelerator Program (MAP) has recently been created to propose and execute this R&D program.

Geer, Steve; /Fermilab; Zisman, Mike; /LBL, Berkeley

2011-08-01T23:59:59.000Z

463

Modulational effects in accelerators  

SciTech Connect

We discuss effects of field modulations in accelerators, specifically those that can be used for operational beam diagnostics and beam halo control. In transverse beam dynamics, combined effects of nonlinear resonances and tune modulations influence diffusion rates with applied tune modulation has been demonstrated. In the longitudinal domain, applied RF phase and voltage modulations provide mechanisms for parasitic halo transport, useful in slow crystal extraction. Experimental experiences with transverse tune and RF modulations are also discussed.

Satogata, T.

1997-12-01T23:59:59.000Z

464

Linear induction accelerator  

DOE Patents (OSTI)

A linear induction accelerator includes a plurality of adder cavities arranged in a series and provided in a structure which is evacuated so that a vacuum inductance is provided between each adder cavity and the structure. An energy storage system for the adder cavities includes a pulsed current source and a respective plurality of bipolar converting networks connected thereto. The bipolar high-voltage, high-repetition-rate square pulse train sets and resets the cavities. 4 figs.

Buttram, M.T.; Ginn, J.W.

1988-06-21T23:59:59.000Z

465

Accelerate Energy Productivity 2030  

Energy.gov (U.S. Department of Energy (DOE))

The U.S. Department of Energy, the Council on Competitiveness, and the Alliance to Save Energy are teaming up for Accelerate Energy Productivity 2030, an initiative to double U.S. energy productivity by 2030. This effort continues support for the goal the President set in his 2013 State of the Union address to double energy productivity, measured by GDP per unit of energy use, from the 2010 level by 2030.

466

Accelerator and Beam Science, ABS, Accelerator Operations and Technology,  

NLE Websites -- All DOE Office Websites (Extended Search)

Accelerator Concepts Accelerator Concepts Injectors Operations Physics CONTACTS Group Leader Robert Garnett Deputy Group Leader Kenneth Johnson Office Administrator Monica Sanchez Phone: (505) 667-2846 Put a short description of the graphic or its primary message here Accelerator and Beam Science The Accelerator and Beam Science (AOT-ABS) Group at Los Alamos addresses physics aspects of the driver accelerator for the LANSCE spallation neutron source and related topics. These activities are wide ranging and include generating negative and positive ions in plasma ion sources, creating ion beams from these particles, accelerating the ion beams in linear accelerator structures up to an energy of 800 MeV, compressing the negative hydrogen beam to packets of sub-microsecond duration and accumulating beam current in the Proton Storage Ring, and

467

Berkeley Proton Linear Accelerator  

DOE R&D Accomplishments (OSTI)

A linear accelerator, which increases the energy of protons from a 4 Mev Van de Graaff injector, to a final energy of 31.5 Mev, has been constructed. The accelerator consists of a cavity 40 feet long and 39 inches in diameter, excited at resonance in a longitudinal electric mode with a radio-frequency power of about 2.2 x 10{sup 6} watts peak at 202.5 mc. Acceleration is made possible by the introduction of 46 axial "drift tubes" into the cavity, which is designed such that the particles traverse the distance between the centers of successive tubes in one cycle of the r.f. power. The protons are longitudinally stable as in the synchrotron, and are stabilized transversely by the action of converging fields produced by focusing grids. The electrical cavity is constructed like an inverted airplane fuselage and is supported in a vacuum tank. Power is supplied by 9 high powered oscillators fed from a pulse generator of the artificial transmission line type.

Alvarez, L. W.; Bradner, H.; Franck, J.; Gordon, H.; Gow, J. D.; Marshall, L. C.; Oppenheimer, F. F.; Panofsky, W. K. H.; Richman, C.; Woodyard, J. R.

1953-10-13T23:59:59.000Z

468

Ultra-high-resolution alpha spectrometry for nuclear forensics and safeguards applications  

SciTech Connect

We will present our work on the development of ultra-high-resolution detectors for alpha particle spectrometry. These detectors, based on superconducting transition-edge sensors, offer energy resolution that is five to ten times better than conventional silicon detectors. Using these microcalorimeter detectors, the isotopic composition of mixed-actinide samples can be determined rapidly without the need for actinide separation chemistry to isolate each element, or mass spectrometry to separate isotopic signatures that can not be resolved using traditional alpha spectrometry (e.g. Pu-239/Pu-240, or Pu-238/Am-241). This paper will cover the detector and measurement system, actinide source preparation, and the quantitative isotopic analysis of a number of forensics- and safeguards-relevant radioactive sources.

Bacrania, Minesh K [Los Alamos National Laboratory; Croce, Mark [Los Alamos National Laboratory; Bond, Evelyn [Los Alamos National Laboratory; Dry, Donald [Los Alamos National Laboratory; Moody, W. Allen [Los Alamos National Laboratory; Lamont, Stephen [Los Alamos National Laboratory; Rabin, Michael [Los Alamos National Laboratory; Rim, Jung [Los Alamos National Laboratory; Smith, Audrey [Los Alamos National Laboratory; Beall, James [NIST-BOULDER; Bennett, Douglas [NIST-BOULDER; Kotsubo, Vincent [NIST-BOULDER; Horansky, Robert [NIST-BOULDER; Hilton, Gene [NIST-BOULDER; Schmidt, Daniel [NIST-BOULDER; Ullom, Joel [NIST-BOULDER; Cantor, Robin [STAR CRYOELECTRONICS

2010-01-01T23:59:59.000Z

469

Recent Advances in Plasma Acceleration  

SciTech Connect

The costs and the time scales of colliders intended to reach the energy frontier are such that it is important to explore new methods of accelerating particles to high energies. Plasma-based accelerators are particularly attractive because they are capable of producing accelerating fields that are orders of magnitude larger than those used in conventional colliders. In these accelerators a drive beam, either laser or particle, produces a plasma wave (wakefield) that accelerates charged particles. The ultimate utility of plasma accelerators will depend on sustaining ultra-high accelerating fields over a substantial length to achieve a significant energy gain. More than 42 GeV energy gain was achieved in an 85 cm long plasma wakefield accelerator driven by a 42 GeV electron drive beam in the Final Focus Test Beam (FFTB) Facility at SLAC. Most of the beam electrons lose energy to the plasma wave, but some electrons in the back of the same beam pulse are accelerated with a field of {approx}52 GV/m. This effectively doubles their energy, producing the energy gain of the 3 km long SLAC accelerator in less than a meter for a small fraction of the electrons in the injected bunch. Prospects for a drive-witness bunch configuration and high-gradient positron acceleration experiments planned for the SABER facility will be discussed.

Hogan, Mark

2007-03-19T23:59:59.000Z

470

Fermilab | Illinois Accelerator Research Center | Fermilab Core...  

NLE Websites -- All DOE Office Websites (Extended Search)

Refrigeration systems Control, Interlock, and Data acquisition systems VHDL, PLD, PLC, DSP programming Accelerator Engineering Complete accelerator design, fabrication,...

471

Siemens Technology Accelerator | Open Energy Information  

Open Energy Info (EERE)

Siemens Technology Accelerator Place: Germany Sector: Services Product: General Financial & Legal Services ( Subsidiary Division ) References: Siemens Technology Accelerator1...

472

Safety of Accelerator Facilities - DOE Directives, Delegations...  

NLE Websites -- All DOE Office Websites (Extended Search)

Health, Environmental Protection, Facility Authorization, Safety The order defines accelerators and establishes accelerator specific safety requirements and approval authorities...

473

Accelerating Clean Energy Adoption (Fact Sheet), Weatherization...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Accelerating Clean Energy Adoption (Fact Sheet), Weatherization and Intergovernmental Program (WIP) Accelerating Clean Energy Adoption (Fact Sheet), Weatherization and...

474

Accelerating Energy Savings Performance Contracting Through Model...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

Accelerating Energy Savings Performance Contracting Through Model Statewide Programs Accelerating Energy Savings Performance Contracting Through Model Statewide Programs Provides...

475

Human Plasma Proteome Analysis by Multidimensional Chromatography Prefractionation and Linear Ion Trap Mass  

E-Print Network (OSTI)

to facilitate human plasma proteome research. Keywords: proteomics · human plasma · mass spectrometry · two the past decades of plasma proteome research works based on 2-DE:2,14-20 the highest quantity of identified

Tian, Weidong

476

Matrixassisted laser desorption/ionization mass spectrometric analysis of aliphatic biodegradable photoluminescent polymers  

E-Print Network (OSTI)

established that the new ILMs provided good spottospot reproducibility and high ionization efficiency compared/ionization mass spectrometry (MALDIMS). The polymers, formed by a condensation reaction of three components

Yang, Jian

477

RAPID COMMUNICATIONS IN MASS SPECTROMETRY Rapid Commun. Mass Spectrom. 2004; 18: 27062712  

E-Print Network (OSTI)

techniques to generate gas-phase ions from samples in condensed phases which have revolutionized collision gas into a cell located on the ion flight path. Introduction of collision gas into an analyzer

Kim, Myung Soo

478

RAPID COMMUNICATIONS IN MASS SPECTROMETRY Rapid Commun. Mass Spectrom. 2005; 19: 25282538  

E-Print Network (OSTI)

the collision-induced decomposition spectra of ammoniated triglycerides as a function of fatty acid chain length of the collision-induced decomposition (CID) products of ammoniated TAGs (ammonium ion adducts) were examined corresponding to loss of that fatty acid. Mechanisms of the formation and decomposition of ammoniated TAGs

Evans, Jason

479

Bio-mass for biomass: biological mass spectrometry techniques for biomass fast pyrolysis oils.  

E-Print Network (OSTI)

??Biomass fast pyrolysis oils, or bio-oils, are a promising renewable energy source to supplement or replace petroleum-based products and fuels. However, there is a current… (more)

Dalluge, Erica A.

2013-01-01T23:59:59.000Z

480

Inhomogeneity implies accelerated expansion  

Science Journals Connector (OSTI)

The Einstein equations for an inhomogeneous irrotational dust universe are analyzed. A set of mild assumptions, all of which are shared by the standard Friedmann-Lemaitre-Robertson-Walker–type scenarios, results in a model that depends only on the distribution of scalar spatial curvature. If the shape of this distribution is made to fit the structure of the present Universe, with most of the matter in galaxy clusters and very little in the voids that will eventually dominate the volume, then there is a period of accelerated expansion after cluster formation, even in the absence of a cosmological constant.

Harald Skarke

2014-02-10T23:59:59.000Z

Note: This page contains sample records for the topic "accelerator mass spectrometry" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


481

Black holes at accelerators.  

E-Print Network (OSTI)

ar X iv :h ep -p h/ 05 11 12 8v 3 6 A pr 2 00 6 Black Holes at Accelerators Bryan Webber Cavendish Laboratory, University of Cambridge, Cambridge CB3 0HE, UK In theories with large extra dimensions and TeV-scale gravity, black holes... 2000 3000 Missing ET (GeV) Ar bi tra ry S ca le p p ? QCD SUSY 5 TeV BH (n=6) 5 TeV BH (n=2) (PT > 600 GeV) (SUGRA point 5) Figure 10: Missing transverse energy for various processes at the LHC. 4.2. Event Characteristics Turning from single...

Webber, Bryan R

482

Argonne Accelerator Institute  

NLE Websites -- All DOE Office Websites (Extended Search)

Fermilab Collaboration Fermilab Collaboration Lee Teng Scholarship Program Useful Links The Argonne Accelerator Institute Historical Document Collection Document Access Guide The documents in this collection are held in several repositories, some of which have restricted access. This guide explains the different types of access, and specifies the access levels for each repository. Repositories Name Access Argonne National Laboratory Document Open Access Argonne Research Library Hard Copy Only Beam Dynamics Newsletter Open Access DOE Information Bridge Open Access IEEE Xplore Library Subscription Required JACoW Open Access Journal of Applied Physics Subscription Required Nuclear Instruments & Methods in Physics Research, Section A Subscription Required Physical Review A Subscription Required

483

THE USE OF LARGE APERTURE ACCELERATING TUBES AT HIGH POTENTIAL GRADIENTS  

E-Print Network (OSTI)

observed in a mass analysis of the residual vacuum. Before removal of the accelerating tubes the mercury1507 THE USE OF LARGE APERTURE ACCELERATING TUBES AT HIGH POTENTIAL GRADIENTS J. H. BROADHURST John H. Williams Laboratory of Nuclear Physics, University of Minnesota, Minneapolis, Minnesota 55455, U

Paris-Sud XI, Université de

484

Fossil packrat middens and the tandem accelerator mass spectrometer  

Science Journals Connector (OSTI)

... glacial standard date (15.7 kyr, A-1581)14. The presence of this low desert shrub in a pinyon-juniper-oak woodland, an anomalous association by current standards, remains ... bigelovii) woodland/chaparral community which presently occurs much higher in elevation than the present Sonoran desert- ...

Thomas R. Van Devender; Paul S. Martin; Robert S. Thompson; Kenneth L. Cole; A. J. Timothy Jull; Austin Long; Laurence J. Toolin; Douglas J. Donahue

1985-10-17T23:59:59.000Z

485

Magnetic Insulation for Electrostatic Accelerators  

SciTech Connect

The voltage gradient which can be sustained between electrodes without electrical breakdowns is usually one of the most important parameters in determining the performance which can be obtained in an electrostatic accelerator. We have recently proposed a technique which might permit reliable operation of electrostatic accelerators at higher electric field gradients, perhaps also with less time required for the conditioning process in such accelerators. The idea is to run an electric current through each accelerator stage so as to produce a magnetic field which envelopes each electrode and its electrically conducting support structures. Having the magnetic field everywhere parallel to the conducting surfaces in the accelerator should impede the emission of electrons, and inhibit their ability to acquire energy from the electric field, thus reducing the chance that local electron emission will initiate an arc. A relatively simple experiment to assess this technique is being planned. If successful, this technique might eventually find applicability in electrostatic accelerators for fusion and other applications.

Grisham, L. R. [Princeton Plasma Physics Laboratory, P. O. Box 451, Princeton, New Jersey 08543 (United States)

2011-09-26T23:59:59.000Z

486

Self-force on an accelerated particle  

Science Journals Connector (OSTI)

We calculate the singular field of an accelerated point particle (scalar charge, electric charge or small gravitating mass) moving on an accelerated (nongeodesic) trajectory in a generic background spacetime. Using a mode-sum regularization scheme, we obtain explicit expressions for the self-force regularization parameters. We use a Lorentz gauge for the electromangetic and gravitational cases. This work extends the work of Barack and Ori [1] who demonstrated that the regularization parameters for a point particle in geodesic motion in a Schwarzschild spacetime can be described solely by the leading and subleading terms in the mode-sum (commonly known as the A and B terms) and that all terms of higher order in ? vanish upon summation (later they showed the same behavior for geodesic motion in Kerr [2], [3]). We demonstrate that these properties are universal to point particles moving through any smooth spacetime along arbitrary (accelerated) trajectories. Our renormalization scheme is based on, but not identical to, the Quinn-Wald axioms. As we develop our approach, we review and extend work showing that that different definitions of the singular field used in the literature are equivalent to our approach. Because our approach does not assume geodesic motion of the perturbing particle, we are able use our mode-sum formalism to explicitly recover a well-known result: The self-force on static scalar charges near a Schwarzschild black hole vanishes.

Thomas M. Linz; John L. Friedman; Alan G. Wiseman

2014-07-23T23:59:59.000Z

487

Modern electron accelerators for radiography  

SciTech Connect

Over the past dozen years or so there have been significant advances in electron accelerators designed specifically for radiography of hydrodynamic experiments. Accelerator technology has evolved to accomodate the radiographers' contitiuing quest for multiple images in t h e and space:, improvements in electron beam quality have resulted in smaller radiographic spot sizes for better resolution, while higher radiation do% now provides imprcwed penetration of large, dense objects. Inductive isolation and acceleration techniques have played a ley rob in these advances.

Ekdahl, C. A. (Carl A.)

2001-01-01T23:59:59.000Z

488

Cast dielectric composite linear accelerator  

DOE Patents (OSTI)

A linear accelerator having cast dielectric composite layers integrally formed with conductor electrodes in a solventless fabrication process, with the cast dielectric composite preferably having a nanoparticle filler in an organic polymer such as a thermosetting resin. By incorporating this cast dielectric composite the dielectric constant of critical insulating layers of the transmission lines of the accelerator are increased while simultaneously maintaining high dielectric strengths for the accelerator.

Sanders, David M. (Livermore, CA); Sampayan, Stephen (Manteca, CA); Slenes, Kirk (Albuquerque, NM); Stoller, H. M. (Albuquerque, NM)

2009-11-10T23:59:59.000Z

489

Accelerating and Retarding Anomalous Diffusion  

E-Print Network (OSTI)

In this paper Gaussian models of retarded and accelerated anomalous diffusion are considered. Stochastic differential equations of fractional order driven by single or multiple fractional Gaussian noise terms are introduced to describe retarding and accelerating subdiffusion and superdiffusion. Short and long time asymptotic limits of the mean squared displacement of the stochastic processes associated with the solutions of these equations are studied. Specific cases of these equations are shown to provide possible descriptions of retarding or accelerating anomalous diffusion.

Chai Hok Eab; S. C. Lim

2012-01-14T23:59:59.000Z

490

Extending Penning trap mass measurements with SHIPTRAP to the heaviest elements  

SciTech Connect

Penning-trap mass spectrometry of radionuclides provides accurate mass values and absolute binding energies. Such mass measurements are sensitive indicators of the nuclear structure evolution far away from stability. Recently, direct mass measurements have been extended to the heavy elements nobelium (Z=102) and lawrencium (Z=103) with the Penning-trap mass spectrometer SHIPTRAP. The results probe nuclear shell effects at N=152. New developments will pave the way to access even heavier nuclides.

Block, M.; Ackermann, D.; Herfurth, F.; Hofmann, S. [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, 64291 Darmstadt (Germany); Blaum, K. [Max-Planck-Institut fuer Kernphysik, 69117 Heidelberg, Germany and Ruprecht-Karls-Universitaet, 69120 Heidelberg (Germany); Droese, C.; Marx, G.; Schweikhard, L. [Ernst-Moritz-Arndt-Universitaet, 17487 Greifswald (Germany); Duellmann, Ch. E. [Johannes Gutenberg-Universitaet, 55099 Mainz, Germany and GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, 64291 Darmstadt, Germany and Helmholtz-Institut Mainz, 55099 Mainz (Germany); Eibach, M. [Ruprecht-Karls-Universitaet, 69120 Heidelberg, Germany and Johannes Gutenberg-Universitaet, 55099 Mainz (Germany); Eliseev, S