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Note: This page contains sample records for the topic "accelerator mass spectrometry" from the National Library of EnergyBeta (NLEBeta).
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1

Accelerator Mass Spectrometry: Extreme Sensitivity in Biological ...  

THE LLNL TECHNOLOGY COMPANY PRODUCT 24 Partnering Today: Technology Transfer Highlights Accelerator Mass Spectrometry: Extreme Sensitivity in Biological Research

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

Small system for tritium accelerator mass spectrometry  

DOE Patents (OSTI)

Apparatus for ionizing and accelerating a sample containing isotopes of hydrogen and detecting the ratios of hydrogen isotopes contained in the sample is disclosed. An ion source generates a substantially linear ion beam including ions of tritium from the sample. A radio-frequency quadrupole accelerator is directly coupled to and axially aligned with the source at an angle of substantially zero degrees. The accelerator accelerates species of the sample having different mass to different energy levels along the same axis as the ion beam. A spectrometer is used to detect the concentration of tritium ions in the sample. In one form of the invention, an energy loss spectrometer is used which includes a foil to block the passage of hydrogen, deuterium and .sup.3 He ions, and a surface barrier or scintillation detector to detect the concentration of tritium ions. In another form of the invention, a combined momentum/energy loss spectrometer is used which includes a magnet to separate the ion beams, with Faraday cups to measure the hydrogen and deuterium and a surface barrier or scintillation detector for the tritium ions.

Roberts, Mark L. (Livermore, CA); Davis, Jay C. (Livermore, CA)

1993-01-01T23:59:59.000Z

4

Small system for tritium accelerator mass spectrometry  

DOE Patents (OSTI)

Apparatus for ionizing and accelerating a sample containing isotopes of hydrogen and detecting the ratios of hydrogen isotopes contained in the sample is disclosed. An ion source generates a substantially linear ion beam including ions of tritium from the sample. A radio-frequency quadrupole accelerator is directly coupled to and axially aligned with the source at an angle of substantially zero degrees. The accelerator accelerates species of the sample having different mass to different energy levels along the same axis as the ion beam. A spectrometer is used to detect the concentration of tritium ions in the sample. In one form of the invention, an energy loss spectrometer is used which includes a foil to block the passage of hydrogen, deuterium and [sup 3]He ions, and a surface barrier or scintillation detector to detect the concentration of tritium ions. In another form of the invention, a combined momentum/energy loss spectrometer is used which includes a magnet to separate the ion beams, with Faraday cups to measure the hydrogen and deuterium and a surface barrier or scintillation detector for the tritium ions.

Roberts, M.L.; Davis, J.C.

1993-02-23T23:59:59.000Z

5

Small system for tritium accelerator mass spectrometry  

DOE Patents (OSTI)

This invention is comprised of an apparatus for ionizing and accelerating a sample containing isotopes of hydrogen and detecting the ratios of hydrogen isotopes contained in the sample. An ion source generates a substantially linear ion beam including ions of tritium from the sample. A radiofrequency quadrupole accelerator is directly coupled to and axially aligned with the source at an angle of substantially zero degrees. The accelerator accelerates species of the sample having different mass to different energy levels along the same axis as the ion beam. A spectrometer is used to detect the concentration of tritium ions in the sample. In one form of the invention, an energy loss spectrometer is used which includes a foil to block the passage of hydrogen, deuterium and {sup 3}He ions, and a surface barrier or scintillation detector to detect the concentration of tritium ions. In another form of the invention, a combined momentum/energy loss spectrometer is used which includes a magnet to separate the ion beams, with Faraday cups to measure the hydrogen and deuterium and a surface barrier or scintillation detector for the tritium ions.

Roberts, M.L.; Davis, J.C.

1991-12-31T23:59:59.000Z

6

Accelerator mass spectrometry as a bioanalytical tool for nutritional research  

SciTech Connect

Accelerator Mass Spectrometry is a mass spectrometric method of detecting long-lived radioisotopes without regard to their decay products or half-life. The technique is normally applied to geochronology, but recently has been developed for bioanalytical tracing. AMS detects isotope concentrations to parts per quadrillion, quantifying labeled biochemicals to attomole levels in milligram- sized samples. Its advantages over non-isotopeic and stable isotope labeling methods are reviewed and examples of analytical integrity, sensitivity, specificity, and applicability are provided.

Vogel, J.S.; Turteltaub, K.W.

1997-09-01T23:59:59.000Z

7

Toward laser ablation Accelerator Mass Spectrometry of actinides  

Science Conference Proceedings (OSTI)

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

8

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

Office of Science (SC) Website

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...

9

Transition of Iodine Analysis to Accelerator Mass Spectrometry  

SciTech Connect

Funding was received from NA-22 to investigate transitioning iodine isotopic analyses to an accelerator mass spectrometry (AMS) system. The present method uses gas-phase chemistry followed by thermal ionization mass spectrometry (TIMS). It was anticipated that the AMS approach could provide comparable data, with improved background levels and superior sample throughput. An aqueous extraction method was developed for removal of iodine species from high-volume air filters. Ethanol and sodium hydroxide, plus heating and ultrasonic treatment, were used to successfully extract iodine from loaded high-volume air filters. Portions of the same filters were also processed in the traditional method and analyzed by TIMS for comparison. Aliquot parts of the aqueous extracts were analyzed by AMS at the Swiss Federal Institute of Technology. Idaho National Laboratory (INL) personnel visited several AMS laboratories in the US, Spain, and Switzerland. Experience with AMS systems from several manufacturers was gained, and relationships were developed with key personnel at the laboratories. Three batches of samples were analyzed in Switzerland, and one in Spain. Results show that the INL extraction method successfully extracted enough iodine from high-volume air filters to allow AMS analysis. Comparison of the AMS and TIMS data is very encouraging; while the TIMS showed about forty percent more atoms of 129I, the 129/127 ratios tracked each other very well between the two methods. The time required for analysis is greatly reduced for the aqueous extraction/AMS approach. For a hypothetical batch of thirty samples, the AMS methodology is about five 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 for TIMS. This results from the fundamental mechanisms of ionization in the AMS system and cleanup of molecular interferences. We showed that an aqueous 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.

J. E. Delmore

2010-09-01T23:59:59.000Z

10

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)

11

Analytical Validation of Accelerator Mass Spectrometry for Pharmaceutical Development: the Measurement of Carbon-14 Isotope Ratio.  

SciTech Connect

Accelerator mass spectrometry (AMS) is an isotope based measurement technology that utilizes carbon-14 labeled compounds in the pharmaceutical development process to measure compounds at very low concentrations, empowers microdosing as an investigational tool, and extends the utility of {sup 14}C labeled compounds to dramatically lower levels. It is a form of isotope ratio mass spectrometry that can provide either measurements of total compound equivalents or, when coupled to separation technology such as chromatography, quantitation of specific compounds. The properties of AMS as a measurement technique are investigated here, and the parameters of method validation are shown. AMS, independent of any separation technique to which it may be coupled, is shown to be accurate, linear, precise, and robust. As the sensitivity and universality of AMS is constantly being explored and expanded, this work underpins many areas of pharmaceutical development including drug metabolism as well as absorption, distribution and excretion of pharmaceutical compounds as a fundamental step in drug development. The validation parameters for pharmaceutical analyses were examined for the accelerator mass spectrometry measurement of {sup 14}C/C ratio, independent of chemical separation procedures. The isotope ratio measurement was specific (owing to the {sup 14}C label), stable across samples storage conditions for at least one year, linear over 4 orders of magnitude with an analytical range from one tenth Modern to at least 2000 Modern (instrument specific). Further, accuracy was excellent between 1 and 3 percent while precision expressed as coefficient of variation is between 1 and 6% determined primarily by radiocarbon content and the time spent analyzing a sample. Sensitivity, expressed as LOD and LLOQ was 1 and 10 attomoles of carbon-14 (which can be expressed as compound equivalents) and for a typical small molecule labeled at 10% incorporated with {sup 14}C corresponds to 30 fg equivalents. AMS provides an sensitive, accurate and precise method of measuring drug compounds in biological matrices.

Keck, B D; Ognibene, T; Vogel, J S

2010-02-05T23:59:59.000Z

12

Determination of the stellar (n,gamma) cross section of 40Ca with accelerator mass spectrometry  

E-Print Network (OSTI)

The stellar (n,gamma) cross section of 40Ca at kT=25 keV has been measured with a combination of the activation technique and accelerator mass spectrometry (AMS). This combination is required when direct off-line counting of the produced activity is compromised by the long half-life and/or missing gamma-ray transitions. The neutron activations were performed at the Karlsruhe Van de Graaff accelerator using the quasistellar neutron spectrum of kT=25 keV produced by the 7Li(p,n)7Be reaction. The subsequent AMS measurements were carried out at the Vienna Environmental Research Accelerator (VERA) with a 3 MV tandem accelerator. The doubly magic 40Ca is a bottle-neck isotope in incomplete silicon burning, and its neutron capture cross section determines the amount of leakage, thus impacting on the eventual production of iron group elements. Because of its high abundance, 40Ca can also play a secondary role as "neutron poison" for the s-process. Previous determinations of this value at stellar energies were based on time-of-flight measurements. Our method uses an independent approach, and yields for the Maxwellian-averaged cross section at kT=30 keV a value of 30 keV= 5.73+/-0.34 mb.

I. Dillmann; C. Domingo-Pardo; M. Heil; F. Käppeler; A. Wallner; O. Forstner; R. Golser; W. Kutschera; A. Priller; P. Steier; A. Mengoni; R. Gallino; M. Paul; C. Vockenhuber

2009-07-01T23:59:59.000Z

13

Accelerator Mass Spectrometry Measurements of Plutonium in Sediment and Seawater from the Marshall Islands  

Science Conference Proceedings (OSTI)

During the summer 2000, I was given the opportunity to work for about three months as a technical trainee at Lawrence Livermore National Laboratory, or LLNL as I will refer to it hereafter. University of California runs this Department of Energy laboratory, which is located 70 km east of San Francisco, in the small city of Livermore. This master thesis in Radioecology is based on the work I did here. LLNL, as a second U.S.-facility for development of nuclear weapons, was built in Livermore in the beginning of the 1950's (Los Alamos in New Mexico was the other one). It has since then also become a 'science center' for a number of areas like magnetic and laser fusion energy, non-nuclear energy, biomedicine, and environmental science. The Laboratory's mission has changed over the years to meet new national needs. The following two statements were found on the homepage of LLNL (http://www.llnl.gov), at 2001-03-05, where also information about the laboratory and the scientific projects that takes place there, can be found. 'Our primary mission is to ensure that the nation's nuclear weapons remain safe, secure, and reliable and to prevent the spread and use of nuclear weapons worldwide'. 'Our goal is to apply the best science and technology to enhance the security and well-being of the nation and to make the world a safer place.' The Marshall Islands Dose Assessment and Radioecology group at the Health and Ecological Assessments division employed me, and I also worked to some extent with the Centre for Accelerator Mass Spectrometry (CAMS) group. The work I did at LLNL can be divided into two parts. In the first part Plutonium (Pu) measurements in sediments from the Rongelap atoll in Marshall Islands, using Accelerator Mass Spectrometry (AMS) were done. The method for measuring these kinds of samples is well understood at LLNL since soil samples have been measured with AMS for Pu in the past. Therefore it was the results that were of main interest and not the technique. The second part was to take advantage of AMS's very high sensitivity by measure the Pu-concentrations in small volumes (0.04-1 L) of seawater. The technique for using AMS at Pu-measurements in seawater is relatively new and the main task for me was to find out a method that could work in practice. The area where the sediment samples and the water samples were collected are high above background levels for many radionuclides, including Pu, because of the detonation of the nuclear bomb code-named Castle Bravo, in 1954.

Leisvik, M; Hamilton, T

2001-08-01T23:59:59.000Z

14

Theoretical Mass Spectrometry  

Science Conference Proceedings (OSTI)

... Mass spectrometry is an important technique in analytical chemistry, essential in areas including drug development, criminal ... Facilities/Tools Used: ...

2013-03-19T23:59:59.000Z

15

First accelerator mass spectrometry {sup 14}C dates documenting contemporaneity of nonanalog species in late Pleistocene mammal communities  

Science Conference Proceedings (OSTI)

Worldwide late Pleistocene terrestrial mammal faunas are characterized by stratigraphic associations of species that now have exclusive geographic ranges. These have been interpreted as either taphonomically mixed or representative of communities that no longer exist. Accelerator mass spectrometry {sup 14}C dates (n = 60) on single bones of stratigraphically associated fossil micromammals from two American and two Russian sites document for the first time that currently allopatric mammals occurred together between 12,000 and 22,000 yr B.P. on two continents. The existence of mammal communities without modern analogs demonstrates that Northern Hemisphere biological communities are ephemeral and that many modern biomes are younger than 12 ka. Future climate change may result in new nonanalog communities.

Stafford, T.W. Jr.; Semken, H.A. Jr.; Graham, R.W.; Klippel, W.F.; Markova, A.; Smirnov, N.G.; Southon, J.

1999-10-01T23:59:59.000Z

16

EMSL: Capabilities: Mass Spectrometry Experts  

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

Related EMSL User Projects Mass Spectrometry Tools are Applied to all Science Themes Next-Generation Mass Spectrometry Proteomics Research Resource for Integrative Biology...

17

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,

18

Single event mass spectrometry  

DOE Patents (OSTI)

A means and method for single event time of flight mass spectrometry for analysis of specimen materials. The method of the invention includes pulsing an ion source imposing at least one pulsed ion onto the specimen to produce a corresponding emission of at least one electrically charged particle. The emitted particle is then dissociated into a charged ion component and an uncharged neutral component. The ion and neutral components are then detected. The time of flight of the components are recorded and can be used to analyze the predecessor of the components, and therefore the specimen material. When more than one ion particle is emitted from the specimen per single ion impact, the single event time of flight mass spectrometer described here furnis This invention was made with Government support under Contract No. W-7405-ENG82 awarded by the Department of Energy. The Government has certain rights in the invention.

Conzemius, Robert J. (Ames, IA)

1990-01-16T23:59:59.000Z

19

EMSL: Capabilities: Mass Spectrometry  

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

Five linear ion traps (one with ETD) Three triple-quadrupole spectrometers Three ion mobility spectrometry (IMS) - time-of-flight (TOF) spectrometers Seventeen custom HPLC,...

20

MANTRA: An Integral Reactor Physics Experiment to Infer Actinide Capture Cross-sections from Thorium to Californium with Accelerator Mass Spectrometry  

SciTech Connect

The principle of the proposed experiment is to irradiate very pure actinide samples in the Advanced Test Reactor at INL and, after a given time, determine the amount of the different transmutation products. The determination of the nuclide densities before and after neutron irradiation will allow inference of effective neutron capture cross-sections. This approach has been used in the past and the novelty of this experiment is that the atom densities of the different transmutation products will be determined using the Accelerator Mass Spectrometry technique at the ATLAS facility located at ANL. It is currently planned to irradiate the following isotopes: 232Th, 235U, 236U, 238U, 237Np, 238Pu, 239Pu, 240Pu, 241Pu, 242Pu, 241Am, 243Am, 244Cm and 248Cm.

G. Youinou; C. McGrath; G. Imel; M. Paul; R. Pardo; F. Kondev; M. Salvatores; G. Palmiotti

2011-08-01T23:59:59.000Z

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

Linear electric field mass spectrometry  

DOE Patents (OSTI)

A mass spectrometer and methods for mass spectrometry are described. The apparatus is compact and of low weight and has a low power requirement, making it suitable for use on a space satellite and as a portable detector for the presence of substances. High mass resolution measurements are made by timing ions moving through a gridless cylindrically symmetric linear electric field. 8 figs.

McComas, D.J.; Nordholt, J.E.

1992-12-01T23:59:59.000Z

22

Linear electric field mass spectrometry  

DOE Patents (OSTI)

A mass spectrometer and methods for mass spectrometry. The apparatus is compact and of low weight and has a low power requirement, making it suitable for use on a space satellite and as a portable detector for the presence of substances. High mass resolution measurements are made by timing ions moving through a gridless cylindrically symmetric linear electric field.

McComas, David J. (Los Alamos, NM); Nordholt, Jane E. (Los Alamos, NM)

1992-01-01T23:59:59.000Z

23

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

24

Quantification of absorption, retention and elimination of two different oral doses of vitamin A in Zambian boys using accelerator mass spectrometry  

SciTech Connect

A recent survey indicated that high-dose vitamin A supplements (HD-VAS) had no apparent effect on vitamin A (VA) status of Zambian children <5 y of age. To explore possible reasons for the lack of response to HD-VAS among Zambian children, we quantified the absorption, retention, and urinary elimination of either a single HDVAS (60 mg) or a smaller dose of stable isotope (SI)-labeled VA (5 mg), which was used to estimate VA pool size, in 3-4 y old Zambian boys (n = 4 for each VA dose). A 25 nCi tracer dose of [{sup 14}C{sub 2}]-labeled VA was co-administered with the HD-VAS or SI-labeled VA, and 24-hr stool and urine samples were collected for 3 and 7 consecutive days, respectively, and 24-hr urine samples at 4 later time points. Accelerator Mass Spectrometry (AMS) was used to measure the cumulative excretion of {sup 14}C in stool and urine 3d after dosing to estimate, respectively, absorption and retention of the VAS and SI-labeled VA. The urinary elimination rate (UER) was estimated by plotting {sup 14}C in urine vs. time, and fitting an exponential equation to the data. Estimates of mean absorption, retention and the UER were 83.8 {+-} 7.1%, 76.3 {+-} 6.7%, and 1.9 {+-} 0.6%/d, respectively, for the HD-VAS and 76.5 {+-} 9.5%, 71.1 {+-} 9.4%, and 1.8 {+-} 1.2%/d, respectively for the smaller dose of SI-labeled VA. Estimates of absorption, retention and the UER did not differ by size of the VA dose administered (P=0.26, 0.40, 0.88, respectively). Estimated absorption and retention were negatively associated with reported fever (P=0.011) and malaria (P =0.010). HD-VAS and SI-labeled VA were adequately absorbed, retained and utilized in apparently healthy Zambian preschool-age boys, although absorption and retention may be affected by recent infections.

Aklamati, E K; Mulenga, M; Dueker, S R; Buchholz, B A; Peerson, J M; Kafwembe, E; Brown, K H; Haskell, M J

2009-10-12T23:59:59.000Z

25

Determination of the Tissue Distribution and Excretion by Accelerator Mass Spectrometry of the Nonadecapeptide 14C-Moli1901 in Beagle dogs after Intratracheal Instillation  

SciTech Connect

Administration of {sup 14}C-Moli1901 (duramycin, 2622U90), a 19 amino acid polycyclic peptide by intratracheal instillation (approximately 100 {micro}g) into the left cranial lobe of the lung of beagle dogs resulted in retention of 64% of the dose in the left cranial lobe for up to 28 days. In this study, we used accelerator mass spectrometry (AMS) to quantify Moli901 following administration of only 0.045 {micro}Ci of {sup 14}C-Moli901 per dog. Limits of quantitation of AMS were 0.03 (urine) to 0.3 (feces) ng equiv. Moli1901/g. Whole blood and plasma concentrations of {sup 14}C were <5ng/ml at all times after the dose. Concentrations of {sup 14}C in whole blood and plasma declined over the first day after the dose and rose thereafter, with the rise in plasma concentrations lagging behind those in whole blood. During the first 3 days after the dose, plasma accounted for the majority of {sup 14}C in whole blood, but after that time, plasma accounted for only 25-30% of the {sup 14}C in whole blood. Tissue (left and right caudal lung lobe, liver, kidney, spleen, brain) and bile concentrations were low, always less than 0.25% the concentrations found in the left cranial lung lobe. Approximately 13% of the dose was eliminated in urine and feces in 28 days, with fecal elimination accounting for about 10% of the dose. The data presented here are consistent with that obtained in other species. Moli1901 is slowly absorbed and excreted from the lung, and it does not accumulate in other tissues. Moli1901 is currently in the clinic and has proven to be safe in single dose studies in human volunteers and cystic fibrosis patients by the inhalation route. No information on the disposition of the compound in humans is available. This study in dogs demonstrates the feasibility of obtaining that information using {sup 14}C-Moli1901 and AMS.

Rickert, D E; Dingley, K H; Ubick, E; Dix, K J; Molina, L

2004-07-02T23:59:59.000Z

26

Available Technologies: Nanostructure Initiator Mass Spectrometry ...  

Using time dependent isotopic labeling and mass spectrometry imaging, researchers at Berkeley Lab and the University of California, Berkeley have developed a ...

27

Automated Surface Sampling Probe for Mass Spectrometry  

Dr. Gary Van Berkel and colleagues have developed a liquid microjunction surface sampling probe (LMJ?SSP). The LMJ?SSP provides mass spectrometry with ...

28

Giga-Dalton Mass Spectrometry  

Current techniques to study large bio?molecules using mass spectrometer require fragmentation for the mass?to?charge ratios to be within the working range of the mass spectrometer. Analysis of the data is complex and often requires simulation ...

29

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

30

Linear electric field mass spectrometry  

DOE Patents (OSTI)

A mass spectrometer is described having a low weight and low power requirement, for use in space. It can be used to analyze the ionized particles in the region of the spacecraft on which it is mounted. High mass resolution measurements are made by timing ions moving through a gridless cylindrically sysmetric linear electric field.

McComas, D.J.; Nordholt, J.E.

1991-03-29T23:59:59.000Z

31

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

32

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

33

CAMS Center for Accelerator Mass Spectrometry  

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

research Lichen research Dinosaur bone research Biology Earth Science About CAMS Tour CAMS History of CAMS Meet the CAMS Staff CAMS Publications CAMS Home Seminars Download...

34

Emerging Technologies in Mass Spectrometry Imaging  

E-Print Network (OSTI)

Mass spectrometry imaging (MSI) as an analytical tool for bio-molecular and bio-medical research targets, accurate compound localization and identification. In terms of dedicated instrumentation, this translates into the demand for more detail in the image dimension (spatial resolution) and in the spectral dimension (mass resolution and accuracy), preferably combined in one instrument. At the same time, large area biological tissue samples require fast acquisition schemes, instrument automation and a robust data infrastructure. This review discusses the analytical capabilities of an "ideal" MSI instrument for bio-molecular and bio-medical molecular imaging. The analytical attributes of such an ideal system are contrasted with technological and methodological challenges in MSI. In particular, innovative instrumentation for high spatial resolution imaging in combination with high sample throughput is discussed. Detector technology that targets various shortcomings of conventional imaging detector systems is hig...

Jungmann, Julia H

2013-01-01T23:59:59.000Z

35

Secondary Ion Mass Spectrometry of Environmental Aerosols  

Science Conference Proceedings (OSTI)

Atmospheric particles influence many aspects of climate, air quality and human health. Understanding the composition, chemistry and behavior of atmospheric aerosols is a key remaining challenge in improving climate models. Furthermore, particles may be traced back to a particular source based on composition, stable isotope ratios, or the presence of particular surface chemistries. Finally, the characterization of atmospheric particles in the workplace plays an important role in understanding the potential for exposure and environmental and human health effects to engineered and natural nanoscale particles. Secondary ion mass spectrometry (SIMS) is a useful tool in determining any of several aspects of the structure, composition and chemistry of these particles. Often used in conjunction with other surface analysis and electron microscopy methods, SIMS has been used to determine or confirm reactions on and in particles, the presence of particular organic species on the surface of atmospheric aerosols and several other interesting and relevant findings. Various versions of SIMS instruments – dynamic SIMS, time of flight secondary ion mass spectrometry or TOF-SIMS, nanoSIMS – have been used to determine specific aspects of aerosol structure and chemistry. This article describes the strengths of each type of SIMS instrument in the characterization of aerosols, along with guidance on sample preparation, specific characterization specific to the particular information sought in the analysis. Examples and guidance are given for each type of SIMS analysis.

Gaspar, Daniel J.; Cliff, John B.

2010-08-01T23:59:59.000Z

36

Activation Measurements for Thermal Neutrons, U.S. Measurements of 36Cl in Mineral Samples from Hiroshima and Nagasaki; and Measurement of 63 Ni in Copper Samples From Hiroshima by Accelerator Mass Spectrometry  

SciTech Connect

The present paper presents the {sup 36}Cl measurement effort in the US. A large number of {sup 36}Cl measurements have been made in both granite and concrete samples obtained from various locations and distances in Hiroshima and Nagasaki. These measurements employed accelerator mass spectrometry (AMS) to quantify the number of atoms of {sup 36}Cl per atom of total Cl in the sample. Results from these measurements are presented here and discussed in the context of the DS02 dosimetry reevaluation effort for Hiroshima and Nagasaki atomic-bomb survivors. The production of {sup 36}Cl by bomb neutrons in mineral samples from Hiroshima and Nagasaki was primarily via the reaction {sup 35}Cl(n,{gamma}){sup 36}Cl. This reaction has a substantial thermal neutron cross-section (43.6 b at 0.025 eV) and the product has a long half-life (301,000 y). hence, it is well suited for neutron-activation detection in Hiroshima and Nagasaki using AMS more than 50 years after the bombings. A less important reaction for bomb neutrons, {sup 39}K(n,{alpha}){sup 36}Cl, typically produces less than 10% of the {sup 36}Cl in mineral samples such as granite and concrete, which contain {approx} 2% potassium. In 1988, only a year after the publication of the DS86 final report (Roesch 1987), it was demonstrated experimentally that {sup 36}Cl measured using AMS should be able to detect the thermal neutron fluences at the large distances most relevant to the A-bomb survivor dosimetry. Subsequent measurements in mineral samples from both Hiroshima and Nagasaki validated the experimental findings. The potential utility of {sup 36}Cl as a thermal neutron detector in Hiroshima was first presented by Haberstock et al. who employed the Munich AMS facility to measure {sup 36}Cl/Cl ratios in a gravestone from near the hypocenter. That work subsequently resulted in an expanded {sup 36}Cl effort in Germany that paralleled the US work. More recently, there have also been {sup 36}Cl measurements made by a Japanese group. The impetus for the extensive {sup 36}Cl and other neutron activation measurements was the recognized need to validate the neutron component of the dose in Hiroshima. Although this was suggested at the time of the DS86 Final Report, where it was stated that the calculated neutron doses for survivors could possibly be wrong, the paucity of neutron validation measurements available at that time prevented adequate resolution of this matter. It was not until additional measurements and data evaluations were made that it became clear that more work was required to better understand the discrepancies observed for thermal neutrons in Hiroshima. This resulted in a large number of additional neutron activation measurements in Hiroshima and Nagasaki by scientists in the US, Japan, and Germany. The results presented here for {sup 36}Cl, together with measurements made by other scientists and for other isotopes, now provide a much improved measurement basis for the validation of neutrons in Hiroshima.

Tore Straume; Alfredo A. Marchetti; Stephen D. Egbert; James A. Roberts; Ping Men; Shoichiro Fujita; Kiyoshi Shizuma; Masaharu Hoshi; G. Rugel; W. Ruhm; G. Korschinek; J. E. McAninch; K. L. Carroll; T. Faestermann; K. Knie; R. E. Martinelli; A. Wallner; C. Wallner

2005-01-14T23:59:59.000Z

37

Molecular Beam Mass Spectrometry (MBMS) (Revised) (Fact Sheet)  

DOE Green Energy (OSTI)

This fact sheet provides information about Molecular Beam Mass Spectrometry (MBMS) capabilities and applications at NREL's National Bioenergy Center. NREL has six MBMS systems that researchers and industry partners can use to understand thermochemical biomass conversion and biomass composition recalcitrance.

Not Available

2011-07-01T23:59:59.000Z

38

Characterization of phenolic resins with thermogravimetry-mass spectrometry  

Science Conference Proceedings (OSTI)

As part of an advanced material research program, thermogravimetry-mass spectrometry (TG-MS) analysis of a phenolic resin was carried out recently for the study of the curing of the prepolymer, solvent extraction, and carbonization of the polymer at high temperature in inert atmosphere. These steps are critical to the quality of the produced advanced material. In addition to TG-MS, several other complementary techniques were also employed for the analysis of the phenolic resin prepolymer and its curing and thermal degradation products. These techniques include pyrolysis-gas chromatography-mass spectrometry, direct insertion probe-mass spectrometry and gas chromatography-mass spectrometry. 7 refs., 5 figs., 3 tabs.

Chang, Cherng; Tackett, J.R.

1990-01-01T23:59:59.000Z

39

Signal variation in single particle aerosol mass spectrometry  

E-Print Network (OSTI)

Rapid and accurate detection of airborne micro-particles is currently an important problem in national security. One approach to such detection, bioaerosol mass spectrometry (BAMS), is currently under development at Lawrence ...

Wissner-Gross, Zachary Daniel

2007-01-01T23:59:59.000Z

40

The power of mass spectrometry in the detection of fraud  

Science Conference Proceedings (OSTI)

Fraudulent products cost industry billions of dollars each year. Perfumes are a good example. The power of mass spectrometry in the detection of fraud Inform Magazine Analytical Chemistry Biochemistry Biotechnology Bert Poepping Fraudulent pro

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

Apparatus And Method For Hydrogen And Oxygen Mass Spectrometry...  

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

Of The Terrestrial Magnetosphere A detector element for mass spectrometry of a flux of heavy and light ions. Available for thumbnail of Feynman Center (505) 665-9090 Email...

42

Tropospheric Aerosol Chemistry via Aerosol Mass Spectrometry  

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

chemical information needed to interpret mass spectra. The challenge is to separate primary and secondary; anthropogenic, biogenic and biomass burning sources - and...

43

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

44

Resonance Ionization Mass Spectrometry System for Measurement of Environmental Samples  

Science Conference Proceedings (OSTI)

A resonance ionization mass spectrometry (RIMS) system has been developed at the National Institute of Standards and Technology (NIST) for sensitive and selective determination of radio?cesium in the environment. The overall efficiency was determined to be 4×10?7 with a combined (laser and mass spectrometer) selectivity of 108 for both 135Cs and 137Cs with respect to 133Cs. RIMS isotopic ratio measurements of 135Cs/ 137Cs were performed on a nuclear fuel burn?up sample and compared to measurements on a similar system at Pacific Northwest National Laboratory (PNNL) and to conventional thermal ionization mass spectrometry (TIMS). Results of preliminary RIMS investigations on a freshwater lake sediment sample are also discussed.

L. Pibida; C. A. McMahon; W. Nörtershäuser; B. A. Bushaw

2002-01-01T23:59:59.000Z

45

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

46

Fission Yield Measurements by Inductively Coupled Plasma Mass-Spectrometry  

SciTech Connect

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

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

2009-11-01T23:59:59.000Z

47

Conditioning of ion sources for mass spectrometry of plasmas  

DOE Green Energy (OSTI)

Mass spectrometry is a useful diagnostic technique for monitoring plasma species and plasma-surface interactions. In order to maximize the sensitivity of measurements of hydrogen-fueled fusion plasmas or hydrogen-based discharge cleaning and etching plasmas, the ion sources of mass spectrometers are operated at or near the high pressure limit of 10/sup -4/ Torr (10/sup -2/ Pa). Such high ambient pressures of hydrogen give rise to high background levels of residual gases such as H/sub 2/O, CO, and CH/sub 4/, due to surface reactions on the ion source electrodes. For a commonly used ion source configuration, the residual gas production is a linear function of the ambient H/sub 2/ pressure. Hydrogen conditioning can reduce the absolute residual gas levels. Steady-state residual gas production is observed in a conditioned ion source, which is related to a balance of diffusion and sorption on the electrode surfaces.

Dylla, H.F.; Blanchard, W.R.

1983-02-01T23:59:59.000Z

48

Method for predicting peptide detection in mass spectrometry  

SciTech Connect

A method of predicting whether a peptide present in a biological sample will be detected by analysis with a mass spectrometer. The method uses at least one mass spectrometer to perform repeated analysis of a sample containing peptides from proteins with known amino acids. The method then generates a data set of peptides identified as contained within the sample by the repeated analysis. The method then calculates the probability that a specific peptide in the data set was detected in the repeated analysis. The method then creates a plurality of vectors, where each vector has a plurality of dimensions, and each dimension represents a property of one or more of the amino acids present in each peptide and adjacent peptides in the data set. Using these vectors, the method then generates an algorithm from the plurality of vectors and the calculated probabilities that specific peptides in the data set were detected in the repeated analysis. The algorithm is thus capable of calculating the probability that a hypothetical peptide represented as a vector will be detected by a mass spectrometry based proteomic platform, given that the peptide is present in a sample introduced into a mass spectrometer.

Kangas, Lars [West Richland, WA; Smith, Richard D [Richland, WA; Petritis, Konstantinos [Richland, WA

2010-07-13T23:59:59.000Z

49

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

50

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

51

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

52

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

SciTech Connect

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

53

Instrumentation development for coupling ion/ion reactions and ion mobility in biological mass spectrometry.  

E-Print Network (OSTI)

??The development of mass spectrometry (MS) instrumentation for novel biological applications, specifically, the development of instrumentation that integrates ion/ion reaction capabilities in an ion trap… (more)

Soyk, Matthew William

2008-01-01T23:59:59.000Z

54

Mass Spectrometry for Translational Proteomics: Progress and Clinical Implications  

SciTech Connect

Mass spectrometry (MS)-based proteomics measurements have become increasingly utilized in a wide range of biological and biomedical applications, and have significantly enhanced the understanding of the complex and dynamic nature of the proteome and its connections to biology and diseases. While some MS techniques such as those for targeted analysis are increasingly applied with great success, others such as global quantitative analysis (for e.g. biomarker discovery) are more challenging and continue to be developed and refined to provide the desired throughput, sensitivity and/ or specificity. New MS capabilities and proteomics-based pipelines/strategies also keep enhancing for the advancement of clinical proteomics applications such as protein biomarker discovery and validation. Herein, we provide a brief review to summarize the current state of MS-based proteomics with respect to its advantages and present limitations, while highlighting its potential in future clinical applications.

Baker, Erin Shammel; Liu, Tao; Petyuk, Vladislav A.; Burnum-Johnson, Kristin E.; Ibrahim, Yehia M.; Anderson, Gordon A.; Smith, Richard D.

2012-08-31T23:59:59.000Z

55

Proteomics by FTICR Mass Spectrometry: Top Down and Bottom Up  

SciTech Connect

This review offers a broad overview of recent FTICR applications and technological developments in the field of proteomics, directed to a variety of people with different expertise and interests. Both the ''bottom-up'' (peptide level) and ''top-down'' (intact protein level) approaches will be covered and various related aspects will be discussed and illustrated with examples that are among the best available references in the literature. ''Bottom-up topics include peptide fragmentation, the AMT approach and DREAMS technology, quantitative proteomics, post-translational modifications, and special FTICR software focused on peptide and protein identification. Topics in the ''top-down'' part include various aspects of high-mass measurements, protein tandem mass spectrometry, protein confirmations, protein-protein complexes, as well as some esoteric applications that may become more practical in the coming years. Finally, examples of integrating both approaches and medical proteomics applications using FTICR will be provided, closing with an outlook of what may be coming our way sooner than later.

Bogdanov, Bogdan; Smith, Richard D.

2005-03-31T23:59:59.000Z

56

Developing Fieldable Systems for Chemical Sensing Using Field Asymmetric Ion Mobility Spectrometry and Mass Spectrometry  

SciTech Connect

Currently, there is an urgent need for field-rugged and field-programmable sensor systems that provide highly selective, universal monitoring of vapors and aerosols at detectable levels from persons or areas involved with illicit chemical/biological/explosives (CBE) production. These devices must be portable, low cost, robust, and provide accurate measurements to avoid both false positive and negative results. Furthermore, the information provided by the devices must be received in a timely manner so that informed decisions can be immediately made and the appropriate actions taken. Two technologies that are unparalleled in their sensitivity, selectivity, and trace-level detection capabilities are field asymmetric ion mobility spectrometry (FAIMS) and mass spectrometry. Here, we will show progress that has been made toward developing fieldable FAIMS systems and mass spectrometers. Working in collaboration with Sionex Corporation, the microDMx detector was equipped with a continuous air sampling system to develop selective methods for the analysis of compounds of interest. A microdiaphragm pump (KNF Neuberger, Inc.) is used to pull in gas-phase analytes directly from the air for separation and detection with the FAIMS system. The FAIMS evaluation platform (SVAC) unit currently measures 9.8-inch x 4.6-inch x 3.2-inch, weighs 3.1 lb, and utilizes a {sup 63}Ni source to ionize incoming compounds. Analytes entering the unit are separated and identified by their characteristic response to the compensation voltage (V{sub c}) at a given rf field strength (V{sub rf}). This response has been observed to be unique for a wide range of substances studied. If additional verification were required or a targeted analyte present in a complex chemical matrix, a FAIMS unit equipped with a fast gas chromatography column has been evaluated. The unit combines the separation capabilities of gas chromatography with the selectivity of FAIMS. It measures 9.5-inch x 5.25-inch x 3.5-inch, weighs 3.8 lb, and uses a 10.6 eV photoionization source. Analytes are identified both by their elution time from the column and by the characteristic response in the FAIMS spectrum. Analysis times required to obtain results for most analytes examined are less than three minutes. A fieldable mass spectrometer system is also being developed that includes sampling, ionization, mass selection and detection, vacuum technology, and analytical methodology with remote data transmission. Multiple methods for mass selection are being explored, including both Penning and Paul type ion traps as well as a quadrupole system to determine which is best suited for a portable mass spectrometer. Several ionization sources and ion counting methods will also be evaluated to establish their effectiveness with each system. The intended result of this project is a handheld mass spectrometer system capable of field deployment for the detection and identification of a wide range of gas-phase CBE species.

Kevin Kyle, Stephan Weeks, R. Trainham

2008-03-01T23:59:59.000Z

57

Extension of the Focusable Mass Range in Distance-of-Flight Mass Spectrometry with Multiple Detectors  

SciTech Connect

Since the underlying theory of Distance-of-Flight Mass Spectrometry (DOFMS) was reported in 2007,[1] laboratory results[2, 3] have proven its practical viability. However, these previous implementations of DOFMS considered ion detection only over narrow DOF-detection windows, with 25-mm being the greatest detection length explored. These small mass windows cannot be used to evaluate how DOFMS focusing performs over greater DOF detection lengths and mass ranges. In the present study, we expand on previous studies by placing two spatially selective ion detectors along the detection plane of the DOFMS instrument. Ion signals are simultaneously collected from both DOF detectors in order to simulate DOFMS performance with a longer spatially selective ion detector.

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

2012-11-15T23:59:59.000Z

58

Laser desorption mass spectrometry for fast DNA analysis  

SciTech Connect

During the past few years, major effort has been directed toward developing mass spectrometry to measure biopolymers because of the great potential benefit to biomedical research. Hellenkamp and his co-workers were the first to report that large polypeptide molecules can be ionized and detected without significant fragmentation when a greater number of nicotinic acid molecules are used as a matrix. This method is now well known as matrix-assisted laser desorption/ionization (MALDI). Since then, various groups have reported measurements of very large proteins by MALDI. Reliable protein analysis by MALDI is more or less well established. However, the application of MALDI to nucleic acids analysis has been found to be much more difficult. Most research on the measurement of nucleic acid by MALDI were stimulated by the Human Genome Project. Up to now, the only method for reliable routine analysis of nucleic acid is gel electrophoresis. Different sizes of nucleic acids can be separated in gel medium when a high electric field is applied to the gel. However, the time needed to separate different sizes of DNA segments usually takes from several minutes to several hours. If MALDI can be successfully used for nucleic acids analysis, the analysis time can be reduced to less than I millisecond. In addition, no tagging with radioactive materials or chemical dyes is needed. In this work, we will review recent progress related to MALDI for DNA analysis.

Chen, C.H.; Ch`ang, L.Y.; Taranenko, N.I.; Allman, S.L.; Tang, K.; Matteson, K.J.

1995-09-01T23:59:59.000Z

59

CNT-based gas ionizers with integrated MEMS gate for portable mass spectrometry applications  

E-Print Network (OSTI)

We report the fabrication and experimental characterization of a novel low-cost carbon nanotube (CNT)-based electron impact ionizer (EII) with integrated gate for portable mass spectrometry applications. The device achieves ...

Velasquez-Garcia, Luis Fernando

60

CNT-based MEMS/NEMS gas ionizers for portable mass spectrometry applications  

E-Print Network (OSTI)

We report the fabrication and experimental characterization of a carbon nanotube (CNT)-based MEMS/NEMS electron impact gas ionizer with an integrated extractor gate for portable mass spectrometry. The ionizer achieves ...

Velasquez-Heller, Luis Fernand

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

Fractal morphology, imaging and mass spectrometry of single aerosol particles in flight  

DOE Data Explorer (OSTI)

This deposition includes the aerosol diffraction images used for phasing, fractal morphology, and time-of-flight mass spectrometry. Files in this deposition are ordered in subdirectories that reflect the specifics.

Loh, N. Duane

62

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.

63

C60 Secondary Ion Fourier Transform Ion Cyclotron Resonance Mass Spectrometry  

SciTech Connect

Secondary ion mass spectrometry (SIMS) has seen increased application for high spatial chemical imaging of complex biological surfaces. The advent and commercial availability of cluster and polyatomic primary ion sources (e.g. Au and Bi cluster and buckminsterfullerene (C60)) provide improved secondary ion yield and decreased fragmentation of surface species, thus accessibility to intact molecular ions. Despite developments in primary ion sources, development of mass spectrometers to fully exploit their advantages has been limited. Tandem mass spectrometry for identification of secondary ions is highly desirable, but implementation has proven to be difficult. Similarly, high mass resolution and high mass measurement accuracy would greatly improve the chemical specificity of SIMS. Here we combine, for the first time, the advantages of a C60 primary ion source with the ultra-high mass resolving power and high mass measurement accuracy of Fourier transform ion cyclotron resonance mass spectrometry. Mass resolving power in excess of 100,000 (m/?m50%) is demonstrated, with mass measurement accuracies below 3 parts-per-million. Imaging of mouse brain tissue at 40 ?m pixel size is shown. Tandem mass spectrometry of ions from biological tissue is demonstrated and molecular formulae can be assigned to fragment ions.

Smith, Donald F.; Robinson, Errol W.; Tolmachev, Aleksey V.; Heeren, Ronald M.; Pasa-Tolic, Ljiljana

2011-12-15T23:59:59.000Z

64

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

Science Conference Proceedings (OSTI)

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

65

Reflection mass spectrometry technique for monitoring and controlling composition during molecular beam epitaxy  

DOE Patents (OSTI)

This invention is comprised of a method for on-line accurate monitoring and precise control of molecular beam epitaxial growth of Groups III-III-V or Groups III-V-V layers in an advanced semiconductor device incorporates reflection mass spectrometry. The reflection mass spectrometry is responsive to intentional perturbations in molecular fluxes incident on a substrate by accurately measuring the molecular fluxes reflected from the substrate. The reflected flux is extremely sensitive to the state of the growing surface and the measurements obtained enable control of newly forming surfaces that are dynamically changing as a result of growth.

Brennan, T.M.; Hammons, B.E.; Tsao, J.Y.

1990-08-15T23:59:59.000Z

66

Reflection mass spectrometry technique for monitoring and controlling composition during molecular beam epitaxy  

DOE Patents (OSTI)

A method for on-line accurate monitoring and precise control of molecular beam epitaxial growth of Groups III-III-V or Groups III-V-V layers in an advanced semiconductor device incorporates reflection mass spectrometry. The reflection mass spectrometry is responsive to intentional perturbations in molecular fluxes incident on a substrate by accurately measuring the molecular fluxes reflected from the substrate. The reflected flux is extremely sensitive to the state of the growing surface and the measurements obtained enable control of newly forming surfaces that are dynamically changing as a result of growth.

Brennan, Thomas M. (Albuquerque, NM); Hammons, B. Eugene (Tijeras, NM); Tsao, Jeffrey Y. (Albuquerque, NM)

1992-01-01T23:59:59.000Z

67

Noise reduction in negative-ion quadrupole mass spectrometry  

DOE Patents (OSTI)

This invention is comprised of 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, P.

1991-12-31T23:59:59.000Z

68

Structural determination of intact proteins using mass spectrometry  

DOE Patents (OSTI)

The present invention relates to novel methods of determining the sequence and structure of proteins. Specifically, the present invention allows for the analysis of intact proteins within a mass spectrometer. Therefore, preparatory separations need not be performed prior to introducing a protein sample into the mass spectrometer. Also disclosed herein are new instrumental developments for enhancing the signal from the desired modified proteins, methods for producing controlled protein fragments in the mass spectrometer, eliminating complex microseparations, and protein preparatory chemical steps necessary for cross-linking based protein structure determination.Additionally, the preferred method of the present invention involves the determination of protein structures utilizing a top-down analysis of protein structures to search for covalent modifications. In the preferred method, intact proteins are ionized and fragmented within the mass spectrometer.

Kruppa, Gary (San Francisco, CA); Schoeniger, Joseph S. (Oakland, CA); Young, Malin M. (Livermore, CA)

2008-05-06T23:59:59.000Z

69

CURRENT SHEET MASS LEAKAGE IN A PULSED PLASMA ACCELERATOR  

E-Print Network (OSTI)

in this dissertation was performed in a pulsed electromagnetic accelerator. 1 #12;Figure 1.1: Diagram of a gas

Choueiri, Edgar

70

Apparatus for preparing a sample for mass spectrometry  

DOE Patents (OSTI)

Disclosed is an apparatus 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.

Villa-Aleman, E.

1992-12-31T23:59:59.000Z

71

Dynamic mass spectrometry: a residual gas analysis method and some applications  

SciTech Connect

Dynamic mass spectrometry is a unique method of residual gas analysis used to monitor and trouble-shoot industrial vacuum process operations. This discussion presents applications and results of the method, and describes the equipment and analytical method developed at Rocky Flats to perform this work. GHT)

McFeeters, T.L.

1981-01-01T23:59:59.000Z

72

High resolution mass spectrometry for the characterization of complex, fossil organic mixtures  

SciTech Connect

High resolution chemical ionization mass spectrometry data support the notion that the size of the stable aromatic clusters is not large in coals except the very high rank coals and inertinite macerals. The desorption chemical ionization spectra appear representative of the sample with little discrimination for molecular types such as aliphatics.

Winans, R.E.; Haas, G.W.; Kim, Yeonhee L.; Hunt, J.E.

1995-08-01T23:59:59.000Z

73

International Journal of Mass Spectrometry 291 (2010) 108117 Contents lists available at ScienceDirect  

E-Print Network (OSTI)

Direct International Journal of Mass Spectrometry journal homepage: www.elsevier.com/locate/ijms Detection of radiation-exposure Keywords: Metabolomic Radiation exposure DMS Ion mobility Electrospray a b s t r a c t Technology to enable rapid screening for radiation exposure has been identified as an important need, and, as a part of a NIH

Brenner, David Jonathan

74

Photon burst mass spectrometry--ultrasensitive detection of rare isotopes  

SciTech Connect

Progress is reported on the development of a new technique for measurement of trace levels of radioisotopes which is based on fluorescence detection of output from a mass spectrometer. Significant achievements include the observation of fluorescence and burst signals from Kr isotopes, including enriched samples of {sup 85}Kr with a 4-collector system. An abundance sensitivity is demonstrated with {sup 83}Kr and {sup 85}Kr.

Hansen, C.S.; Pan, X.J.; Fairbank, W.M. Jr. [Colorado State Univ., Fort Collins, CO (United States). Physics Dept.; Oona, H.; Chamberlin, E.P.; Nogar, N.S.; Fearey, B.L. [Los Alamos National Lab., NM (United States)

1995-02-01T23:59:59.000Z

75

Ion source for high-precision mass spectrometry  

DOE Patents (OSTI)

The invention is directed to a method for increasing the precision of positive-ion relative abundance measurements conducted in a sector mass spectrometer having an ion source for directing a beam of positive ions onto a collimating slit. The method comprises incorporating in the source an electrostatic lens assembly for providing a positive-ion beam of circular cross section for collimation by the slit.

Todd, Peter J. (Oak Ridge, TN); McKown, Henry S. (Oak Ridge, TN); Smith, David H. (Oak Ridge, TN)

1984-01-01T23:59:59.000Z

76

Inductively Coupled Plasma Mass Spectrometry Uranium Error Propagation  

SciTech Connect

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

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

2001-07-01T23:59:59.000Z

77

Quantitative Analysis of Tetramethylenedisulfotetramine ("Tetramine") Spiked into Beverages by Liquid Chromatography Tandem Mass Spectrometry with Validation by Gas Chromatography Mass Spectrometry  

Science Conference Proceedings (OSTI)

Tetramethylenedisulfotetramine, commonly known as tetramine, is a highly neurotoxic rodenticide (human oral LD{sub 50} = 0.1 mg/kg) used in hundreds of deliberate food poisoning events in China. Here we describe a method for quantitation of tetramine spiked into beverages, including milk, juice, tea, cola, and water and cleaned up by C8 solid phase extraction and liquid-liquid extraction. Quantitation by high performance liquid chromatography tandem mass spectrometry (LC/MS/MS) was based upon fragmentation of m/z 347 to m/z 268. The method was validated by gas chromatography mass spectrometry (GC/MS) operated in SIM mode for ions m/z 212, 240, and 360. The limit of quantitation was 0.10 {micro}g/mL by LC/MS/MS versus 0.15 {micro}g/mL for GC/MS. Fortifications of the beverages at 2.5 {micro}g/mL and 0.25 {micro}g/mL were recovered ranging from 73-128% by liquid-liquid extraction for GC/MS analysis, 13-96% by SPE and 10-101% by liquid-liquid extraction for LC/MS/MS analysis.

Owens, J; Hok, S; Alcaraz, A; Koester, C

2008-11-13T23:59:59.000Z

78

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

79

Tandem mass spectrometry for characterization of high-carbon-number geoporphyrins  

Science Conference Proceedings (OSTI)

Geoporphyrins are separated into TCL fractions after being isolated from Boscan oil (West Venezuela) by column chromatography. Analysis of each fraction by electron ionization mass spectrometry identified the porphyrin classes present and their carbon number ranges, but the spectra were extremely complex. Tandem mass spectrometry (MS/MS) allowed selection of molecular ions of individual carbon number porphyrins of the DPEP and etio types for fragmentation by collisionally activated dissociation. Comparison of their daughter and neutral loss spectra with those of porphyrin standards provided the first structural information on individual high-carbon-number geoporphyrins (>C/sub 33/). This information is helpful in the study of their geologic evolution and suggests the potential for using MS/MS data on high-carbon-number geoporphyrins as a parameter in oil exploration. Metalated and demetalated porphyrins of the same carbon number produced similar spectra, suggesting that samples may require less treatment for analysis by MS/MS than by conventional MS.

Johnson, J.V.; Britton, E.D.; Yost, R.A.; Quirke, J.M.E.; Cuesta, L.L.

1986-06-01T23:59:59.000Z

80

B American Society for Mass Spectrometry( 2011 DOI: 10.1007/s13361-011-0179-8  

E-Print Network (OSTI)

A new instrument that combines ion mobility spectrometry (IMS) separations with tandem mass spectrometry in the mobility dimension. Here, we report the development of a new instrument that combines mobility separations Spectrom. (2011) 22:1477Y1485 RESEARCH ARTICLE An Ion Mobility/Ion Trap/Photodissociation Instrument

Clemmer, David E.

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

Compositional Analysis of the High Molecular Weight Ethylene Oxide Propylene Oxide Copolymer by MALDI Mass Spectrometry  

E-Print Network (OSTI)

The composition of narrow distribution poly ethylene oxide-propylene oxide copolymer (Mw ~ 8700 Da) was studied using matrix assisted laser desorption ionization (MALDI) mass spectrometry. The ethylene oxide-propylene oxide copolymer produced oligomers separated by 14 Da. The average resolving power over the entire spectrum was 28,000. Approximately 448 isotopically resolved peaks representing about 56 oligomers are identified. Although agreement between experimental and calculated isotopic distributions was strong, the compositional assignment was difficult. This is due to the large number of possible isobaric components. The purpose of this research is to resolve and study the composition of high mass copolymer such as ethylene oxide-propylene oxide.

Houshia, Orwa Jaber

2012-01-01T23:59:59.000Z

82

Modern Methods for Lipid AnalysisChapter 11 Analysis of Steroids by Liquid Chromatography — Atmospheric Pressure Photoionization Mass Spectrometry  

Science Conference Proceedings (OSTI)

Modern Methods for Lipid Analysis Chapter 11 Analysis of Steroids by Liquid Chromatography — Atmospheric Pressure Photoionization Mass Spectrometry Methods and Analyses eChapters Methods - Analyses Books 7B3610598EB68717295AAD02DBA4F828

83

Modern Methods for Lipid AnalysisChapter 4 Liquid Chromatography/Electrospray Ionization Mass Spectrometry for Analysis of Oxidized Lipids  

Science Conference Proceedings (OSTI)

Modern Methods for Lipid Analysis Chapter 4 Liquid Chromatography/Electrospray Ionization Mass Spectrometry for Analysis of Oxidized Lipids Methods and Analyses eChapters Methods - Analyses Books AOCS Press Downloadable pd

84

Modern Methods for Lipid AnalysisChapter 13 Dual Parallel Liquid Chromatography/Mass Spectrometry for Lipid Analysis  

Science Conference Proceedings (OSTI)

Modern Methods for Lipid Analysis Chapter 13 Dual Parallel Liquid Chromatography/Mass Spectrometry for Lipid Analysis Methods and Analyses eChapters Methods - Analyses Books AOCS Press Downloadable pdf of Chapter

85

Extreme Chromatography: Faster, Hotter, SmallerChapter 8 Multiple Parallel Mass Spectrometry Techniques for Lipid and Vitamin D Analysis  

Science Conference Proceedings (OSTI)

Extreme Chromatography: Faster, Hotter, Smaller Chapter 8 Multiple Parallel Mass Spectrometry Techniques for Lipid and Vitamin D Analysis Methods and Analyses eChapters Methods - Analyses Books AOCS Press Downloadable pdf...

86

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

E-Print Network (OSTI)

Chemical and Biological Systems Research Team: Julia Laskin, Ljiljana Pasa-Toli, Brandi Heath, Ingela Laskin (PNNL) Purpose Multimodal chemical characterization of microbial biofilms focused bacterial colonies Develop novel mass spectrometry-based chemical imaging capabilities broadly applicable

87

Advances in Conjugated Linoleic Acid Research, Vol 2Chapter 2 Gas Chromatography - Mass Spectrometry of Conjugated Linoleic Acids and Metabolites  

Science Conference Proceedings (OSTI)

Advances in Conjugated Linoleic Acid Research, Vol 2 Chapter 2 Gas Chromatography - Mass Spectrometry of Conjugated Linoleic Acids and Metabolites Health Nutrition Biochemistry eChapters Health - Nutrition - Biochemistry Dow

88

Characterization of Individual Nanoparticles and Applications of Nanoparticles in Mass Spectrometry  

E-Print Network (OSTI)

The chemical characterization of individual nanoparticles (NPs) mass spectrometry (SIMS) technique are Au4004+ and C60+. The ionized ejecta from each impact are recorded individually which allows to identify ions emitted from a surface volume of ~10 nm in diameter and 5-10 nm in depth. The mode of analyzing ejecta individually from each single cluster impact gives insight into surface homogeneity, in our case NPs and their immediate surroundings. We show that when the NPs (50 nm Al) are larger than the size of the volume perturbed by the projectile, the secondary ion emission (SI) resembles that of a bulk surface. However, when the NP (5 nm Ag) is of the size range of the volume perturbed by projectile the SI emission is different from that of a bulk surface. As part of this sub-assay volume study, the influence of neighboring NP on the SI emission was examined by using a mixture of different types of NPs (5 nm Au and 5 nm Ag). The methodology of using cluster SIMS via a sequence of stochastic single impacts yield information on the surface coverage of the NPs, as well as the influence of the chemical environment on the type of SI emission. We also present a case of soft landing NPs for laser desorption ionization mass spectrometry. NPs enhance the SI emission in a manner that maintains the integrity of the spatial distribution of molecular species. The results indicate that the application can be extended to imaging mass spectrometry.

Rajagopal Achary, Sidhartha Raja

2010-05-01T23:59:59.000Z

89

230Th-234U Age-Dating Uranium by Mass Spectrometry  

Science Conference Proceedings (OSTI)

This is the standard operating procedure used by the Isotope Ratio Mass Spectrometry Group of the Chemical Sciences Division at LLNL for the preparation of a sample of uranium oxide or uranium metal for {sup 230}Th-{sup 234}U age-dating. The method described here includes the dissolution of a sample of uranium oxide or uranium metal, preparation of a secondary dilution, spiking of separate aliquots for uranium and thorium isotope dilution measurements, and purification of uranium and thorium aliquots for mass spectrometry. This SOP may be applied to uranium samples of unknown purity as in a nuclear forensic investigation, and also to well-characterized samples such as, for example, U{sub 3}O{sub 8} and U-metal certified reference materials. The sample of uranium is transferred to a quartz or PFA vial, concentrated nitric acid is added and the sample is heated on a hotplate at approximately 100 C for several hours until it dissolves. The sample solution is diluted with water to make the solution approximately 4 M HNO{sub 3} and hydrofluoric acid is added to make it 0.05 M HF. A secondary dilution of the primary uranium solution is prepared. Separate aliquots for uranium and thorium isotope dilution measurements are taken and spiked with {sup 233}U and {sup 229}Th, respectively. The spiked aliquot for uranium isotope dilution analysis is purified using EiChrom UTEVA resin. The spiked aliquot for thorium isotope dilution analysis is purified by, first, a 1.8 mL AG1x8 resin bed in 9 M HCl on which U adsorbs and Th passes through; second, adsorbing Th on a 1 mL AG1x8 resin bed in 8 M HNO{sub 3} and then eluting it with 9 M HCl followed by 0.1 M HCl + 0.005 M HF; and third, by passing the Th through a final 1.0 mL AG1x8 resin bed in 9 M HCl. The mass spectrometry is performed using the procedure 'Th and U Mass Spectrometry for {sup 230}Th-{sup 234}U Age Dating'.

Williams, R W; Gaffney, A M

2012-04-18T23:59:59.000Z

90

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

Science Conference Proceedings (OSTI)

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

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

2007-11-13T23:59:59.000Z

91

Coal liquefaction process streams characterization and evaluation. Characterization of coal-derived materials by field desorption mass spectrometry, two-dimensional nuclear magnetic resonance, supercritical fluid extraction, and supercritical fluid chromatography/mass spectrometry  

SciTech Connect

Under contract from the DOE , and in association with CONSOL Inc., Battelle, Pacific Northwest Laboratory (PNL) evaluated four principal and several complementary techniques for the analysis of non-distillable direct coal liquefaction materials in support of process development. Field desorption mass spectrometry (FDMS) and nuclear magnetic resonance (NMR) spectroscopic methods were examined for potential usefulness as techniques to elucidate the chemical structure of residual (nondistillable) direct coal liquefaction derived materials. Supercritical fluid extraction (SFE) and supercritical fluid chromatography/mass spectrometry (SFC/MS) were evaluated for effectiveness in compound-class separation and identification of residual materials. Liquid chromatography (including microcolumn) separation techniques, gas chromatography/mass spectrometry (GC/MS), mass spectrometry/mass spectrometry (MS/MS), and GC/Fourier transform infrared (FTIR) spectroscopy methods were applied to supercritical fluid extracts. The full report authored by the PNL researchers is presented here. The following assessment briefly highlights the major findings of the project, and evaluates the potential of the methods for application to coal liquefaction materials. These results will be incorporated by CONSOL into a general overview of the application of novel analytical techniques to coal-derived materials at the conclusion of CONSOL`s contract.

Campbell, J.A.; Linehan, J.C.; Robins, W.H. [Battelle Pacific Northwest Lab., Richland, WA (United States)

1992-07-01T23:59:59.000Z

92

In situ mass spectrometry in a 10 Torr W chemical vapor deposition process for film thickness metrology  

E-Print Network (OSTI)

widely implemented using in situ sensors, par- ticularly using mass spectrometry or residual gas analysis-process ex situ film weight measurement, provided a working metrology model such that real-time mass spec- cess chemistry, temperature regime, and low-pressure sub- Torr operation of the reactor. Our analysis

Rubloff, Gary W.

93

Molecular Characterization of Nitrogen Containing Organic Compounds in Biomass Burning Aerosols Using High Resolution Mass Spectrometry  

DOE Green Energy (OSTI)

Although nitrogen-containing organic compounds (NOC) are important components of atmospheric aerosols, little is known about their chemical compositions. Here we present detailed characterization of the NOC constituents of biomass burning aerosol (BBA) samples using high resolution electrospray ionization mass spectrometry (ESI/MS). Accurate mass measurements combined with MS/MS fragmentation experiments of selected ions were used to assign molecular structures to individual NOC species. Our results indicate that N-heterocyclic alkaloid compounds - species naturally produced by plants and living organisms - comprise a substantial fraction of NOC in BBA samples collected from test burns of five biomass fuels. High abundance of alkaloids in test burns of ponderosa pine - a widespread tree in the western U.S. areas frequently affected by large scale fires - suggests that N-heterocyclic alkaloids in BBA can play a significant role in dry and wet deposition of fixed nitrogen in this region.

Laskin, Alexander; Smith, Jeffrey S.; Laskin, Julia

2009-05-13T23:59:59.000Z

94

Study of Electrochemical Reactions Using Nanospray Desorption Electrospray Ionization Mass Spectrometry  

Science Conference Proceedings (OSTI)

The combination of electrochemistry (EC) and mass spectrometry (MS) is a powerful analytical tool for studying mechanisms of redox reactions, identification of products and intermediates, and online derivatization/recognition of analytes. This work reports a new coupling interface for EC/MS by employing nanospray desorption electrospray ionization (nano-DESI), a recently developed ambient ionization method. We demonstrate online coupling of nano-DESI-MS with a traditional electrochemical flow cell, in which the electrolyzed solution emanating from the cell is ionized by nano-DESI for MS analysis. Furthermore, we show first coupling of nano-DESI-MS with an interdigitated array (IDA) electrode enabling chemical analysis of electrolyzed samples directly from electrode surfaces. Because of its inherent sensitivity, nano-DESI enables chemical analysis of small volumes and concentrations of sample solution. Specifically, good-quality signal of dopamine and its oxidized form, dopamine ortho-quinone, was obtained using 10 {mu}L of 1 {mu}M solution of dopamine on the IDA. Oxidation of dopamine, reduction of benzodiazepines, and electrochemical derivatization of thiol groups were used to demonstrate the performance of the technique. Our results show the potential of nano-DESI as a novel interface for electrochemical mass spectrometry research.

Liu, Pengyuan; Lanekoff, Ingela T.; Laskin, Julia; Dewald, Howard D.; Chen, Hao

2012-07-03T23:59:59.000Z

95

The Ramsey method in high-precision mass spectrometry with Penning traps: Experimental results  

E-Print Network (OSTI)

The highest precision in direct mass measurements is obtained with Penning trap mass spectrometry. Most experiments use the interconversion of the magnetron and cyclotron motional modes of the stored ion due to excitation by external radiofrequency-quadrupole fields. In this work a new excitation scheme, Ramsey's method of time-separated oscillatory fields, has been successfully tested. It has been shown to reduce significantly the uncertainty in the determination of the cyclotron frequency and thus of the ion mass of interest. The theoretical description of the ion motion excited with Ramsey's method in a Penning trap and subsequently the calculation of the resonance line shapes for different excitation times, pulse structures, and detunings of the quadrupole field has been carried out in a quantum mechanical framework and is discussed in detail in the preceding article in this journal by M. Kretzschmar. Here, the new excitation technique has been applied with the ISOLTRAP mass spectrometer at ISOLDE/CERN for mass measurements on stable as well as short-lived nuclides. The experimental resonances are in agreement with the theoretical predictions and a precision gain close to a factor of four was achieved compared to the use of the conventional excitation technique.

S. George; K. Blaum; F. Herfurth; A. Herlert; M. Kretzschmar; S. Nagy; S. Schwarz; L. Schweikhard; C. Yazidjian

2007-01-22T23:59:59.000Z

96

Accelerators  

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

Accelerators Elementary Particles Detectors Accelerators Visit World Labs For Children - for younger people For Children The Electric Force For Children Electric Force Fields For...

97

Laser Microdissection and Atmospheric Pressure Chemical Ionization Mass Spectrometry Coupled for Multimodal Imaging  

SciTech Connect

This paper describes the coupling of ambient laser ablation surface sampling, accomplished using a laser capture microdissection system, with atmospheric pressure chemical ionization mass spectrometry for high spatial resolution multimodal imaging. A commercial laser capture microdissection system was placed in close proximity to a modified ion source of a mass spectrometer designed to allow for sampling of laser ablated material via a transfer tube directly into the ionization region. Rhodamine 6G dye of red sharpie ink in a laser etched pattern as well as cholesterol and phosphatidylcholine in a cerebellum mouse brain thin tissue section were identified and imaged from full scan mass spectra. A minimal spot diameter of 8 m was achieved using the 10X microscope cutting objective with a lateral oversampling pixel resolution of about 3.7 m. Distinguishing between features approximately 13 m apart in a cerebellum mouse brain thin tissue section was demonstrated in a multimodal fashion including co-registered optical and mass spectral chemical images.

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

2013-01-01T23:59:59.000Z

98

A study of the formation of cluster ions from metal acetates using plasma desorption mass spectrometry  

E-Print Network (OSTI)

A novel application of desorption/ionization methods of mass spectrometry, e. g. plasma desorption mass spectrometry (PDMS), is the analysis of both the composition and structure of solid materials in one experiment. Cluster ions emitted from the impact of a 252Cf fission fragment on a surface may represent a "view" of the solid construction over atomic distances if composed of atoms from adjacent sites in the surface. A clearer understanding of the mechanism of secondary cluster ion formation is necessary to evaluate the usefulness of PDMS as a surface characterization technique. The aim of this research was to use metal acetate samples to study secondary cluster ion formation in PDMS. In two sets of experiments, metal acetates from period IV and group IIB of the periodic table were used to measure the influence on cluster formation by the ground state electronic configuration and the ionic size, respectively, of the metal constituent. Relative yields for homologous negative and positive secondary cluster ions were determined and compared to thermochemical properties of the metal ion or the metal acetate molecule (AHf and lattice energy). Secondary ions in negative PDMS mass spectra attributable to a gas phase recombination formation mechanism follow trends predicted by these thermochemical properties. Another series of cluster ions, however, with the composition [M(Ac)2]Ac-(where Ac = acetate) does not follow the same trends, indicating possible formation via intact emission from the solid surface. Positive secondary cluster ions showed differences from the negative ions both in the relative yield distribution and the types of ions observed. Positive cluster ions from metal acetates from the fourth period of the periodic table were mainly metal oxides. On the other hand, positive clusters ions from the group IIB of the periodic table were mainly mirror images of the negative spectra. These differences suggest that the bonding characteristics of the metal ion play an important role in the secondary cluster ion formation process.

Mendez Silvagnoli, Winston Reinaldo

1995-01-01T23:59:59.000Z

99

LC-IMS-MS Feature Finder: Detecting Multidimensional Liquid Chromatography, Ion Mobility, and Mass Spectrometry Features in Complex Datasets  

SciTech Connect

We introduce a command line software application LC-IMS-MS Feature Finder that searches for molecular ion signatures in multidimensional liquid chromatography-ion mobility spectrometry-mass spectrometry (LC-IMS-MS) data by clustering deisotoped peaks with similar monoisotopic mass, charge state, LC elution time, and ion mobility drift time values. The software application includes an algorithm for detecting and quantifying co-eluting chemical species, including species that exist in multiple conformations that may have been separated in the IMS dimension.

Crowell, Kevin L.; Slysz, Gordon W.; Baker, Erin Shammel; Lamarche, Brian L.; Monroe, Matthew E.; Ibrahim, Yehia M.; Payne, Samuel H.; Anderson, Gordon A.; Smith, Richard D.

2013-09-13T23:59:59.000Z

100

Frequency Dependence of Rotor's Free Falling Acceleration and Inequality of Inertial and Gravity Masses  

E-Print Network (OSTI)

Results of measurements of free falling acceleration of a closed container with a rotor of a mechanical gyroscope placed inside it on the frequency of the rotor rotation are briefly described. Time of separate accelerations measurements is 40 ms, the period of sampling is from 0.5 up to 1.0 minute. In rotation's frequencies range of 20-400 Hz, the negative changes of free falling container acceleration prevail. On individual frequencies the "resonant" maxima and minima of acceleration are observed. The obtained data apparently contradict the equivalence principle of inertial and gravitating masses. The expediency of development of ballistic gravimetry of high time resolution with use of rotating or oscillating test bodies is noted.

Dmitriev, Alexander L

2011-01-01T23:59:59.000Z

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.


101

Frequency Dependence of Rotor's Free Falling Acceleration and Inequality of Inertial and Gravity Masses  

E-Print Network (OSTI)

Results of measurements of free falling acceleration of a closed container with a rotor of a mechanical gyroscope placed inside it on the frequency of the rotor rotation are briefly described. Time of separate accelerations measurements is 40 ms, the period of sampling is from 0.5 up to 1.0 minute. In rotation's frequencies range of 20-400 Hz, the negative changes of free falling container acceleration prevail. On individual frequencies the "resonant" maxima and minima of acceleration are observed. The obtained data apparently contradict the equivalence principle of inertial and gravitating masses. The expediency of development of ballistic gravimetry of high time resolution with use of rotating or oscillating test bodies is noted.

Alexander L. Dmitriev

2011-01-24T23:59:59.000Z

102

Analysis of fission gas release kinetics by on-line mass spectrometry  

SciTech Connect

The release of fission gas (Xe and Kr) and helium out of nuclear fuel materials in normal operation of a nuclear power reactor can constitute a strong limitation of the fuel lifetime. Moreover, radioactive isotopes of Xe and Kr contribute significantly to the global radiological source term released in the primary coolant circuit in case of accidental situations accompanied by fuel rod loss of integrity. As a consequence, fission gas release investigation is of prime importance for the nuclear fuel cycle economy, and is the driven force of numerous R and D programs. In this domain, for solving current fuel behavior understanding issues, preparing the development of new fuels (e.g. for Gen IV power systems) and for improving the modeling prediction capability, there is a marked need for innovations in the instrumentation field, mainly for: . Quantification of very low fission gas concentrations, released from fuel sample and routed in sweeping lines. Monitoring of quick gas release variations by quantification of elementary release during a short period of time. Detection of a large range of atomic masses (e.g. H{sub 2}, HT, He, CO, CO{sub 2}, Ne, Ar, Kr, Xe), together with a performing separation of isotopes for Xe and Kr elements. Coupling measurement of stable and radioactive gas isotopes, by using in parallel mass spectrometry and gamma spectrometry techniques. To fulfill these challenging needs, a common strategy for analysis equipment implementation has been set up thanks to a recently launched collaboration between the CEA and the Univ. of Provence, with the technological support of the Liverpool Univ.. It aims at developing a chronological series of mass spectrometer devices based upon mass filter and 2D/3D ion traps with Fourier transform operating mode and having increasing levels of performances to match the previous challenges for out-of pile and in-pile experiments. The final objective is to install a high performance online mass spectrometer coupled to a gamma spectrometer in the fission product laboratory of the future Jules Horowitz Material Test Reactor. An intermediate step will consist of testing first equipment on an existing experimental facility in the LECA-STAR Hot Cell Laboratory of the CEA Cadarache. This paper presents the scientific and operational stakes linked to fission gas issues, resumes the current state of art for analyzing them in nuclear facilities, then presents the skills gathered through this collaboration to overcome technological bottlenecks. Finally it describes the implementation strategy in nuclear research facilities of the CEA Cadarache. (authors)

Zerega, Y.; Reynard-Carette, C. [Univ. of Provence, Laboratoire Chimie Provence, UMR 6264, Avenue escadrille Normandie - Niemen, F-13397 Marseille (France); Parrat, D. [CEA, Nuclear Energy Div. DEN, CEA Cadarache, F-13108 Saint-Paul-lez-Durance (France); Carette, M. [Univ. of Provence, Laboratoire Chimie Provence, UMR 6264, Avenue escadrille Normandie - Niemen, F-13397 Marseille (France); Brkic, B. [Univ. of Liverpool, Dept. of Electrical Engineering and Electronics, Liverpool L69 3BX (United Kingdom); Lyoussi, A.; Bignan, G. [CEA, Nuclear Energy Div. DEN, CEA Cadarache, F-13108 Saint-Paul-lez-Durance (France); Janulyte, A.; Andre, J. [Univ. of Provence, Laboratoire Chimie Provence, UMR 6264, Avenue escadrille Normandie - Niemen, F-13397 Marseille (France); Pontillon, Y.; Ducros, G. [CEA, Nuclear Energy Div. DEN, CEA Cadarache, F-13108 Saint-Paul-lez-Durance (France); Taylor, S. [Univ. of Liverpool, Dept. of Electrical Engineering and Electronics, Liverpool L69 3BX (United Kingdom)

2011-07-01T23:59:59.000Z

103

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

104

Final Report - Advanced Ion Trap Mass Spectrometry Program - Oak Ridge National Laboratory - Sandia National Laboratory  

Science Conference Proceedings (OSTI)

This report covers the three main projects that collectively comprised the Advanced Ion Trap Mass Spectrometry Program. Chapter 1 describes the direct interrogation of individual particles by laser desorption within the ion trap mass spectrometer analyzer. The goals were (1) to develop an ''intelligent trigger'' capable of distinguishing particles of biological origin from those of nonbiological origin in the background and interferent particles and (2) to explore the capability for individual particle identification. Direct interrogation of particles by laser ablation and ion trap mass spectrometry was shown to have good promise for discriminating between particles of biological origin and those of nonbiological origin, although detailed protocols and operating conditions were not worked out. A library of more than 20,000 spectra of various types of biological particles has been assembled. Methods based on multivariate analysis and on neural networks were used to discriminate between particles of biological origin and those of nonbiological origin. It was possible to discriminate between at least some species of bacteria if mass spectra of several hundred similar particles were obtained. Chapter 2 addresses the development of a new ion trap mass analyzer geometry that offers the potential for a significant increase in ion storage capacity for a given set of analyzer operating conditions. This geometry may lead to the development of smaller, lower-power field-portable ion trap mass spectrometers while retaining laboratory-scale analytical performance. A novel ion trap mass spectrometer based on toroidal ion storage geometry has been developed. The analyzer geometry is based on the edge rotation of a quadrupolar ion trap cross section into the shape of a torus. Initial performance of this device was poor, however, due to the significant contribution of nonlinear fields introduced by the rotation of the symmetric ion-trapping geometry. These nonlinear resonances contributed to poor mass resolution and sensitivity and to erratic ion ejection behavior. To correct for these nonlinear effects, the geometry of the toroid ion trap analyzer has been modified to create an asymmetric torus, as first suggested by computer simulations that predicted significantly improved performance and unit mass resolution for this geometry. A reduced-sized version (one-fifth scale) has been fabricated but was not tested within the scope of this project. Chapter 3 describes groundbreaking progress toward the use of ion-ion chemistry to control the charge state of ions formed by the electrospray ionization process, which in turn enables precision analysis of whole proteins. In addition, this technique may offer the unique possibility of a priori identification of unknown biological material when employed with existing proteomics and genomic databases. Ion-ion chemistry within the ion trap was used to reduce the ions in highly charged states to states of +1 and +2 charges. Reduction in charge greatly simplifies identification of molecular weights of fragments from large biological molecules. This technique enables the analysis of whole proteins as biomarkers for the detection and identification of all three classes of biological weapons (bacteria, toxins, and viruses). In addition to methods development, tests were carried out with samples of tap water, local creek water, and soil (local red clay) spiked with melittin (bee venom), cholera toxin, and virus MS2. All three analytes were identified in tap water and soil; however, all three were problematic for detection in creek water at concentrations of 1 nM. More development of methods is needed.

Whitten, W.B.

2002-12-18T23:59:59.000Z

105

Modern Methods for Lipid AnalysisChapter 8 Analysis of Carotenoids Using Atmospheric Pressure Chemical Ionization Mass Spectrometry  

Science Conference Proceedings (OSTI)

Modern Methods for Lipid Analysis Chapter 8 Analysis of Carotenoids Using Atmospheric Pressure Chemical Ionization Mass Spectrometry Methods and Analyses eChapters Methods - Analyses Books AOCS Press 634F787D8F694E5A50C242671C4B87C5

106

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

Science Conference Proceedings (OSTI)

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

107

ESI/Ion Trap/Ion Mobility/Time-of-Flight Mass Spectrometry for Rapid and Sensitive Analysis of  

E-Print Network (OSTI)

discuss a new separation strategy for biomolecules that is based on differences in ion mobilitiesESI/Ion Trap/Ion Mobility/Time-of-Flight Mass Spectrometry for Rapid and Sensitive Analysis* Department of Chemistry, Indiana University, Bloomington, Indiana 47405 An ion trap/ion mobility

Clemmer, David E.

108

Studies of selenium and xenon in inductively coupled plasma mass spectrometry  

SciTech Connect

Since its development, inductively coupled plasma mass spectrometry (ICP-MS) has been a widely used analytical technique. ICP-MS offers low detection limits, easy determination of isotope ratios, and simple mass spectra from analyte elements. ICP-MS has been successfully employed for many applications including geological, environmental, biological, metallurgical, food, medical, and industrial. One specific application important to many areas of study involves elemental speciation by using ICP-MS as an element specific detector interfaced to liquid chromatography. Elemental speciation information is important and cannot be obtained by atomic spectrometric methods alone which measure only the total concentration of the element present. Part 1 of this study describes the speciation of selenium in human serum by size exclusion chromatography (SEC) and detection by ICP-MS. Although ICP-MS has been widely sued, room for improvement still exists. Difficulties in ICP-MS include noise in the background, matrix effects, clogging of the sampling orifice with deposited solids, and spectral interference caused by polyatomic ions. Previous work has shown that the addition of xenon into the central channel of the ICP decreases polyatomic ion levels. In Part 2 of this work, a fundamental study involving the measurement of the excitation temperature is carried out to further understand xenon`s role in the reduction of polyatomic ions. 155 refs.

Bricker, T.

1994-07-27T23:59:59.000Z

109

An Automated Platform for High-Resolution Tissue Imaging Using Nanospray Desorption Electrospray Ionization Mass Spectrometry  

SciTech Connect

An automated platform has been developed for acquisition and visualization of mass spectrometry imaging (MSI) data using nanospray desorption electrospray ionization (nano-DESI). The new system enables robust operation of the nano-DESI imaging source over many hours. This is achieved by controlling the distance between the sample and the probe by mounting the sample holder onto an automated XYZ stage and defining the tilt of the sample plane. This approach is useful for imaging of relatively flat samples such as thin tissue sections. Custom software called MSI QuickView was developed for visualization of large data sets generated in imaging experiments. MSI QuickView enables fast visualization of the imaging data during data acquisition and detailed processing after the entire image is acquired. The performance of the system is demonstrated by imaging rat brain tissue sections. High resolution mass analysis combined with MS/MS experiments enabled identification of lipids and metabolites in the tissue section. In addition, high dynamic range and sensitivity of the technique allowed us to generate ion images of low-abundance isobaric lipids. High-spatial resolution image acquired over a small region of the tissue section revealed the spatial distribution of an abundant brain metabolite, creatine, in the white and gray matter that is consistent with the literature data obtained using magnetic resonance spectroscopy.

Lanekoff, Ingela T.; Heath, Brandi S.; Liyu, Andrey V.; Thomas, Mathew; Carson, James P.; Laskin, Julia

2012-10-02T23:59:59.000Z

110

Molecular Characterization of Biomass Burning Aerosols Using High Resolution Mass Spectrometry  

DOE Green Energy (OSTI)

Chemical characterizations of atmospheric aerosols is a serious analytical challenge because of the complexity of particulate matter analyte composed of a large number of compounds with a wide range of molecular structures, physico-chemical properties, and reactivity. In this study chemical composition of biomass burning organic aerosol (BBOA) samples is characterized by high resolution electrospray ionization mass spectrometry (ESI/MS). Accurate mass measurement combined with Kendrick analysis allowed us to assign elemental composition for hundreds of compounds in the range of m/z values of 50-1000. ESI/MS spectra of different BBOA samples contain a variety of distinct, sample specific, characteristic peaks that can be used as unique markers for different types of biofuels. Our results indicate that a significant number of high-MW organic compounds in BBOA samples are highly oxidized polar species that can be efficiently detected using ESI/MS but are difficult to observe using the conventional GCMS analysis of aerosol samples. The average O:C ratios obtained for each of the BBOA samples studied in this work are in a strikingly good agreement with the previously reported values obtained using STXM/NEXAFS. The degree of unsaturation of detected organic compounds shows a clear decrease with increase in the molecular weight of the anyalyte molecules. The decrease is particularly pronounced for the samples containing a large number of CH2-based homologous series.

Smith, Jeffrey S.; Laskin, Alexander; Laskin, Julia

2009-02-13T23:59:59.000Z

111

acceleration  

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

middle name. The head of Fermilab's Accelerator Division explains a basic idea of high-energy physics in everyday language. Painless Physics Articles BEAM COOLING August 2, 1996...

112

Multivariate analysis of progressive thermal desorption coupled gas chromatography-mass spectrometry.  

SciTech Connect

Thermal decomposition of poly dimethyl siloxane compounds, Sylgard{reg_sign} 184 and 186, were examined using thermal desorption coupled gas chromatography-mass spectrometry (TD/GC-MS) and multivariate analysis. This work describes a method of producing multiway data using a stepped thermal desorption. The technique involves sequentially heating a sample of the material of interest with subsequent analysis in a commercial GC/MS system. The decomposition chromatograms were analyzed using multivariate analysis tools including principal component analysis (PCA), factor rotation employing the varimax criterion, and multivariate curve resolution. The results of the analysis show seven components related to offgassing of various fractions of siloxanes that vary as a function of temperature. Thermal desorption coupled with gas chromatography-mass spectrometry (TD/GC-MS) is a powerful analytical technique for analyzing chemical mixtures. It has great potential in numerous analytic areas including materials analysis, sports medicine, in the detection of designer drugs; and biological research for metabolomics. Data analysis is complicated, far from automated and can result in high false positive or false negative rates. We have demonstrated a step-wise TD/GC-MS technique that removes more volatile compounds from a sample before extracting the less volatile compounds. This creates an additional dimension of separation before the GC column, while simultaneously generating three-way data. Sandia's proven multivariate analysis methods, when applied to these data, have several advantages over current commercial options. It also has demonstrated potential for success in finding and enabling identification of trace compounds. Several challenges remain, however, including understanding the sources of noise in the data, outlier detection, improving the data pretreatment and analysis methods, developing a software tool for ease of use by the chemist, and demonstrating our belief that this multivariate analysis will enable superior differentiation capabilities. In addition, noise and system artifacts challenge the analysis of GC-MS data collected on lower cost equipment, ubiquitous in commercial laboratories. This research has the potential to affect many areas of analytical chemistry including materials analysis, medical testing, and environmental surveillance. It could also provide a method to measure adsorption parameters for chemical interactions on various surfaces by measuring desorption as a function of temperature for mixtures. We have presented results of a novel method for examining offgas products of a common PDMS material. Our method involves utilizing a stepped TD/GC-MS data acquisition scheme that may be almost totally automated, coupled with multivariate analysis schemes. This method of data generation and analysis can be applied to a number of materials aging and thermal degradation studies.

Van Benthem, Mark Hilary; Mowry, Curtis Dale; Kotula, Paul Gabriel; Borek, Theodore Thaddeus, III

2010-09-01T23:59:59.000Z

113

Facilities: NHMFL 14.5 Tesla Fourier Transform Ion Cyclotron Resonance Mass Spectrometer Citation: A Pseudoatomic Model of the COPII Cage Obtained from Cryo-Electron Microscopy and Mass Spectrometry,  

E-Print Network (OSTI)

Facilities: NHMFL 14.5 Tesla Fourier Transform Ion Cyclotron Resonance Mass Spectrometer Citation ultrahigh-resolution 14.5 tesla Fourier transform ion cyclotron resonance mass spectrometry. The Mag

Weston, Ken

114

Comparative proteogenomics: combining mass spectrometry and comparative genomics to analyze multiple genomes  

SciTech Connect

While bacterial genome annotations have significantly improved in recent years, techniques for bacterial proteome annotation (including post-translational chemical modifications, signal peptides, proteolytic events, etc.) are still in their infancy. At the same time, the number of sequenced bacterial genomes is rising sharply, far outpacing our ability to validate the predicted genes, let alone annotate bacterial proteomes. In this study, we use tandem mass spectrometry (MS/MS) to annotate the proteome of Shewanella oneidensis MR-1, an important microbe for bioremediation. In particular, we provide the first comprehensive map of post-translational modifications in a bacterial genome, including a large number of chemical modifications, signal peptide cleavages and cleavage of N-terminal methionine residues. We also detect multiple genes that were missed or assigned incorrect start positions by gene prediction programs and suggest corrections to improve the gene annotation. This study demonstrates that complementing every genome sequencing project by an MS/MS project would significantly improve both genome and proteome annotations for a reasonable cost.

Gupta, Nitin; Benhamida, Jamal; Bhargava, Vipul; Goodman, Daniel; Kain , Elisabeth; Kerman, Ian; Nguyen , Ngan; Ollikainen, Noah; Rodriguez, Jesse; Wang, J.; Lipton, Mary S.; Romine, Margaret F.; Bafna, Vineet; Smith, Richard D.; Pevzner, Pavel A.

2008-07-30T23:59:59.000Z

115

Imaging Nicotine in Rat Brain Tissue by Use of Nanospray Desorption Electrospray Ionization Mass Spectrometry  

SciTech Connect

Imaging mass spectrometry offers simultaneous detection of drugs, drug metabolites and endogenous substances in a single experiment. This is important when evaluating effects of a drug on a complex organ system such as the brain, where there is a need to understand how regional drug distribution impacts function. Nicotine is an addictive drug and its action in the brain is of high interest. Here we use nanospray desorption electrospray ionization, nano-DESI, imaging to discover the localization of nicotine in rat brain tissue after in vivo administration of nicotine. Nano-DESI is a new ambient technique that enables spatially-resolved analysis of tissue samples without special sample pretreatment. We demonstrate high sensitivity of nano-DESI imaging that enables detection of only 0.7 fmole nicotine per pixel in the complex brain matrix. Furthermore, by adding deuterated nicotine to the solvent, we examined how matrix effects, ion suppression, and normalization affect the observed nicotine distribution. Finally, we provide preliminary results suggesting that nicotine localizes to the hippocampal substructure called dentate gyrus.

Lanekoff, Ingela T.; Thomas, Mathew; Carson, James P.; Smith, Jordan N.; Timchalk, Charles; Laskin, Julia

2013-01-15T23:59:59.000Z

116

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

Office of Science (SC) Website

important application of AMS measurements of the naturally occurring 36ClCl ratio in water (as opposed to the one created by atmospheric and underground nuclear weapons test) is...

117

Accelerator  

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

1. ACCELERATOR PHYSICS OF COLLIDERS Revised July 2011 by D. A. Edwards (DESY) and M. J. Syphers (MSU) 1.1. Luminosity This article provides background for the High-Energy Collider...

118

Combination of chemical reduction and tandem mass spectrometry for the characterization of sulfur-containing fuel constituents  

SciTech Connect

Tandem mass spectrometry has been combined with a calcium/mixed amines reduction system to characterize an SRC-II middle distillate fraction for sulfur-containing polynuclear aromatic hydrocarbons. Parent scans, which characterize a complex mixture for all components which fragment to common structural moieties, were used to identify alkyl-benzothiophenes and dibenzothiophenes as well as alkyl-benzothiophene sulfones. 15 references, 5 figures, 1 table.

Wood, K.V.; Cooks, R.G.; Laugal, J.A.; Benkeser, R.A.

1985-03-01T23:59:59.000Z

119

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

120

IMPULSIVE ACCELERATION OF CORONAL MASS EJECTIONS. II. RELATION TO SOFT X-RAY FLARES AND FILAMENT ERUPTIONS  

SciTech Connect

Using high time cadence images from the STEREO EUVI, COR1, and COR2 instruments, we derived detailed kinematics of the main acceleration stage for a sample of 95 coronal mass ejections (CMEs) in comparison with associated flares and filament eruptions. We found that CMEs associated with flares reveal on average significantly higher peak accelerations and lower acceleration phase durations, initiation heights, and heights, at which they reach their peak velocities and peak accelerations. This means that CMEs that are associated with flares are characterized by higher and more impulsive accelerations and originate from lower in the corona where the magnetic field is stronger. For CMEs that are associated with filament eruptions we found only for the CME peak acceleration significantly lower values than for events that were not associated with filament eruptions. The flare rise time was found to be positively correlated with the CME acceleration duration and negatively correlated with the CME peak acceleration. For the majority of the events the CME acceleration starts before the flare onset (for 75% of the events) and the CME acceleration ends after the soft X-ray (SXR) peak time (for 77% of the events). In {approx}60% of the events, the time difference between the peak time of the flare SXR flux derivative and the peak time of the CME acceleration is smaller than {+-}5 minutes, which hints at a feedback relationship between the CME acceleration and the energy release in the associated flare due to magnetic reconnection.

Bein, B. M.; Berkebile-Stoiser, S.; Veronig, A. M.; Temmer, M. [Kanzelhoehe Observatory-IGAM, Institute of Physics, University of Graz, Universitaetsplatz 5, A-8010 Graz (Austria); Vrsnak, B. [Hvar Observatory, Faculty of Geodesy, University of Zagreb, Kaciceva 26, HR-10000 Zagreb (Croatia)

2012-08-10T23:59:59.000Z

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121

Chemical Analysis of Complex Organic Mixtures Using Reactive Nanospray Desorption Electrospray Ionization Mass Spectrometry  

SciTech Connect

Reactive nanospray desorption electrospray ionization (nano-DESI) combined with high-resolution mass spectrometry was utilized for the analysis of secondary organic aerosol produced through ozonolysis of limonene (LSOA). Previous studies showed that LSOA constituents are multifunctional compounds containing aldehyde and ketone groups. In this study, we used the selectivity of the Girard T (GT) reagent towards carbonyl compounds to examine the utility of reactive nano-DESI for the analysis of complex organic mixtures. In these experiments, 1-100 {micro}M GT solution was used as a working solvent for reactive nano-DESI analysis. Abundant products of a single addition of GT to LSOA constituents were observed at GT concentrations in excess of 10 {micro}M. We found that LSOA compounds with 18-20 carbon atoms (dimers) and 27-30 carbon atoms (trimers) react with GT through a simple addition reaction resulting in formation of the carbinolamine derivative. In contrast, reactions of GT with monomeric species result in formation of both the carbinolamine and the hydrazone derivatives. In addition, several monomers did not react with GT on the timescale of our experiment. These molecules were characterized by relatively high values of the double bond equivalent (DBE) and low oxygen content. Furthermore, because addition of a charged GT tag to a neutral molecule eliminates the discrimination against the low proton affinity compounds in the ionization process, reactive nano-DESI analysis enables quantification of individual compounds in the complex mixture. For example, we were able to estimate for the first time the amounts of dimers and trimers in the LSOA mixture. Specifically, we found that the most abundant LSOA dimer was detected at ca. 0.5 pg level and the total amount of dimers and trimers in the analyzed sample was just around 11 pg. Our results indicate that reactive nano-DESI is a valuable approach for examining the presence of specific functional groups and quantification of compounds possessing these groups in complex mixtures.

Laskin, Julia; Eckert, Peter A.; Roach, Patrick J.; Heath, Brandi S.; Nizkorodov, Sergey A.; Laskin, Alexander

2012-08-21T23:59:59.000Z

122

{sup 99}Tc bioassay by inductively coupled plasma mass spectrometry (ICP-MS)  

Science Conference Proceedings (OSTI)

A means of analyzing {sup 99}Tc in urine by inductively coupled plasma mass spectrometry (ICP-MS) has been developed. Historically, {sup 99}Tc analysis was based on the radiometric detection of the 293 keV E{sub Max} beta decay product by liquid scintillation or gas flow proportional counting. In a urine matrix, the analysis of{sup 99}Tc is plagued with many difficulties using conventional radiometric methods. Difficulties originate during chemical separation due to the volatile nature of Tc{sub 2}O{sub 7} or during radiation detection due to color or chemical quenching. A separation scheme for {sup 99}Tc detection by ICP-MS is given and is proven to be a sensitive and robust analytical alternative. A comparison of methods using radiometric and mass quantitation of {sup 99}Tc has been conducted in water, artificial urine, and real urine matrices at activity levels between 700 and 2,200 dpm/L. Liquid scintillation results based on an external standard quench correction and a quench curve correction method are compared to results obtained by ICP-MS. Each method produced accurate results, however the precision of the ICP-MS results is superior to that of liquid scintillation results. Limits of detection (LOD) for ICP-MS and liquid scintillation detection are 14.67 and 203.4 dpm/L, respectively, in a real urine matrix. In order to determine the basis for the increased precision of the ICP-MS results, the detection sensitivity for each method is derived and measured. The detection sensitivity for the {sup 99}Tc isotope by ICP-MS is 2.175 x 10{sup {minus}7} {+-} 8.990 x 10{sup {minus}9} and by liquid scintillation is 7.434 x 10{sup {minus}14} {+-} 7.461 x 10{sup {minus}15}. A difference by seven orders of magnitude between the two detection systems allows ICP-MS samples to be analyzed for a period of 15 s compared to 3,600 s by liquid scintillation counting with a lower LOD.

Lewis, L.A.

1998-05-01T23:59:59.000Z

123

Accelerating Anisotropic Cosmologies in Brans-Dicke Gravity coupled to a Mass-Varying Vector Field  

E-Print Network (OSTI)

The field equations of Brans-Dicke gravity coupled to a mass-varying vector field are derived. Anisotropic cosmological solutions with a locally rotationally symmetric Bianchi type I metric and time-dependent scalar and electric vector fields are studied. A particular class of exact solutions for which all the variable parameters have a power-law time dependence is given. The universe expands with a constant expansion anisotropy within this class of solutions. We show that the accelerating expansion is driven by the scalar field and the electric vector field can be interpreted as an anisotropic dark-matter source.

Ozgur Akarsu; Tekin Dereli; Neslihan Oflaz

2013-11-11T23:59:59.000Z

124

Mass varying neutrinos, quintessence, and the accelerating expansion of the Universe  

SciTech Connect

We analyze the mass varying neutrino scenario. We consider a minimal model of massless Dirac fermions coupled to a scalar field, mainly in the framework of finite-temperature quantum field theory. We demonstrate that the mass equation we find has nontrivial solutions only for special classes of potentials, and only within certain temperature intervals. We give most of our results for the Ratra-Peebles dark energy (DE) potential. The thermal (temporal) evolution of the model is analyzed. Following the time arrow, the stable, metastable, and unstable phases are predicted. The model predicts that the present Universe is below its critical temperature and accelerates. At the critical point, the Universe undergoes a first-order phase transition from the (meta)stable oscillatory regime to the unstable rolling regime of the DE field. This conclusion agrees with the original idea of quintessence as a force making the Universe roll towards its true vacuum with a zero {Lambda} term. The present mass varying neutrino scenario is free from the coincidence problem, since both the DE density and the neutrino mass are determined by the scale M of the potential. Choosing M{approx}10{sup -3} eV to match the present DE density, we can obtain the present neutrino mass in the range m{approx}10{sup -2}-1 eV and consistent estimates for other parameters of the Universe.

Chitov, Gennady Y.; August, Tyler [Department of Physics, Laurentian University, Ramsey Lake Road, Sudbury, ON, P3E 2C6 (Canada); Natarajan, Aravind [McWilliams Center for Cosmology and Department of Physics, Carnegie Mellon University, 5000 Forbes Ave, Pittsburgh, Pennsylvania 15213 (United States); Kahniashvili, Tina [McWilliams Center for Cosmology and Department of Physics, Carnegie Mellon University, 5000 Forbes Ave, Pittsburgh, Pennsylvania 15213 (United States); Department of Physics, Laurentian University, Ramsey Lake Road, Sudbury, ON, P3E 2C6 (Canada); National Abastumani Astrophysical Observatory, Ilia Chavchavadze State University, 2A Kazbegi Ave, Tbilisi, GE-0160 (Georgia)

2011-02-15T23:59:59.000Z

125

Modern Methods for Lipid AnalysisChapter 12 Toward Total Cellular Lipidome Analysis by ESI Mass Spectrometry from a Crude Lipid Extract  

Science Conference Proceedings (OSTI)

Modern Methods for Lipid Analysis Chapter 12 Toward Total Cellular Lipidome Analysis by ESI Mass Spectrometry from a Crude Lipid Extract Methods and Analyses eChapters Methods - Analyses Books AOCS Press Downloadable pdf ...

126

Lipid Analysis and Lipidomics: New Techniques & ApplicationChapter 3 Global Cellular Lipidome Analyses by Shotgun Lipidomics Using Multidimensional Mass Spectrometry  

Science Conference Proceedings (OSTI)

Lipid Analysis and Lipidomics: New Techniques & Application Chapter 3 Global Cellular Lipidome Analyses by Shotgun Lipidomics Using Multidimensional Mass Spectrometry Methods and Analyses eChapters Methods - Analyses Books 2D17DD82D1DB9F2

127

Modern Methods for Lipid AnalysisCh 6 Regiospecific Analysis of Triacylglycerols using Hi Performance Liquid Chromatography/AtmosphericPressure Chemical Ionization Mass Spectrometry  

Science Conference Proceedings (OSTI)

Modern Methods for Lipid Analysis Ch 6 Regiospecific Analysis of Triacylglycerols using Hi Performance Liquid Chromatography/AtmosphericPressure Chemical Ionization Mass Spectrometry Methods and Analyses eChapters Methods - Analyses Books

128

Modern Methods for Lipid AnalysisChapter 2 Analysis of Phospholipids by Liquid Chromatography Coupled with Online Electrospray Ionization Mass Spectrometry  

Science Conference Proceedings (OSTI)

Modern Methods for Lipid Analysis Chapter 2 Analysis of Phospholipids by Liquid Chromatography Coupled with Online Electrospray Ionization Mass Spectrometry Methods and Analyses eChapters Methods - Analyses Books AOCS Press A76556A5B4

129

Lipid Analysis and Lipidomics: New Techniques & ApplicationChapter 2 An Overview of Modern Mass Spectrometry Methods in the Toolbox of Lipid Chemists and Biochemists  

Science Conference Proceedings (OSTI)

Lipid Analysis and Lipidomics: New Techniques & Application Chapter 2 An Overview of Modern Mass Spectrometry Methods in the Toolbox of Lipid Chemists and Biochemists Methods and Analyses eChapters Methods - Analyses Books Dow

130

Nutrition and Biochemistry of PhospholipidsChapter 9 Compositional Analysis of Complex Mixtures of Sphingolipids by Liquid Chromatography — Tandem Mass Spectrometry  

Science Conference Proceedings (OSTI)

Nutrition and Biochemistry of Phospholipids Chapter 9 Compositional Analysis of Complex Mixtures of Sphingolipids by Liquid Chromatography — Tandem Mass Spectrometry Health Nutrition Biochemistry eChapters Health - Nutrition - Biochemist

131

Modern Methods for Lipid AnalysisChapter 7 Qualitative and Quantitative Analysis of Triacylglycerolsby Atmospheric Pressure Ionization (APCI and ESI) Mass Spectrometry Techniques  

Science Conference Proceedings (OSTI)

Modern Methods for Lipid Analysis Chapter 7 Qualitative and Quantitative Analysis of Triacylglycerolsby Atmospheric Pressure Ionization (APCI and ESI) Mass Spectrometry Techniques Methods and Analyses eChapters Methods - Analyses Books AO

132

Extreme Chromatography: Faster, Hotter, SmallerChapter 6 Silver-ion High-performance Liquid Chromatography—Mass Spectrometry in the Analysis of Lipids  

Science Conference Proceedings (OSTI)

Extreme Chromatography: Faster, Hotter, Smaller Chapter 6 Silver-ion High-performance Liquid Chromatography—Mass Spectrometry in the Analysis of Lipids Methods and Analyses eChapters Methods - Analyses Books Downloadable pdf...

133

Modern Methods for Lipid AnalysisChapter 3 Electrospray Ionization with Low-Energy Collisionally Activated Dissociation Tandem Mass Spectrometry of Complex Lipids:  

Science Conference Proceedings (OSTI)

Modern Methods for Lipid Analysis Chapter 3 Electrospray Ionization with Low-Energy Collisionally Activated Dissociation Tandem Mass Spectrometry of Complex Lipids: Methods and Analyses eChapters Methods - Analyses Books AOCS Press ...

134

Advances in Conjugated Linoleic Acid Research, Volume 3Chapter 6 Structural Characterization of CLA Methyl Esters with Acetonitrile Chemical Ionization Tandem Mass Spectrometry  

Science Conference Proceedings (OSTI)

Advances in Conjugated Linoleic Acid Research, Volume 3 Chapter 6 Structural Characterization of CLA Methyl Esters with Acetonitrile Chemical Ionization Tandem Mass Spectrometry Health Nutrition Biochemistry eChapters Health - Nutrition

135

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

Science Conference Proceedings (OSTI)

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

136

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

137

Differential Mobility Spectrometry/Mass Spectrometry: The Design of a New Mass Spectrometer for Real-Time Chemical Analysis in the Field  

SciTech Connect

The design of a prototype, field-portable mass spectrometer (MS) is described. The MS has been designed with an atmospheric interface in order to couple the system to a commercially available differential mobility spectrometer. The differential mobility spectrometer provides selective injection of trace-level analytes of interest into the inlet of the MS for real-time chemical detection. To accomplish this task, the MS design incorporates the use of an electrodynamic ion funnel to transport the ion beam, generated at atmospheric pressure, to the high-vacuum chamber that houses the mass analyzer. This leads to a design that utilizes two stages of differential pumping to achieve an overall pressure drop from atmosphere (760 Torr) to approximately 1 ×

,

2010-08-01T23:59:59.000Z

138

Gas-phase and Solution-phase Peptide Conformations Studied by Ion Mobility-mass Spectrometry and Molecular Dynamics Simulations  

E-Print Network (OSTI)

Ion mobility spectrometry (IMS) separates ions on the basis of ion-neutral collision cross-sections (CCS, [omega]), which are determined by the geometry or conformation of the ions. The size-based IM separation can be extended to distinguish conformers that have different shapes in cases where shape differences influence the accessible surface area of the molecule. In recent years, IM has rapidly evolved as a structural characterization technique, which has applied on various structural biology problems. In this work, IMS is combined with molecular dynamics simulation (MDS), specially the integrated tempering sampling molecular dynamics simulation (ITS-MDS) to explore the gas-phase conformation space of two molecular systems (i) protonated tryptophan zipper 1 (trpzip1) ions and its six derivatives (ii) alkali metal ion (Na, K and Cs) adducts of gramicidin A (GA). The structural distributions obtained from ITS-MDS are compared well with results obtained from matrix-assisted laser desorption ionization-ion mobility-mass spectrometry (MALDI-IM-MS) for trpzip 1 series and electrospray ionization-ion mobility-mass spectrometry (ESI-IM-MS) for alkali metal ion adducts of GA. Furthermore, the solvent dependence on conformational preferences of the GA dimer is investigated using a combination of mass spectrometry techniques, viz. ESI-IM-MS and hydrogen/deuterium exchange (HDX)-MS, and MDS. The IM experiments reveal three distinct gramicidin A species, detected as the sodium ion adduct ions, [2GA + 2Na]²?, and the equilibrium abundances of the dimer ions varies with solvent polarity. The solution phase conformations are assigned as the parallel and anti-parallel [beta]-helix dimer, and the anti-parallel dimer is the preferred conformation in non-polar organic solvent. The calculated CCS profiles by ITS-MDS agree very well with the experimentally measured CCS profiles, which underscore the utility of the method for determining candidate structures as well as the relative abundances of the candidate structures. The benefit of combining ion mobility measurements with solution-phase H/D exchange is allowing identifications and detail analysis of the solution-phase subgroup conformations, which cannot be uncovered by one method alone.

Chen, Liuxi

2012-08-01T23:59:59.000Z

139

Formic acid oxidation in a polymer electrolyte fuel cell: A real-time mass-spectrometry study  

Science Conference Proceedings (OSTI)

The electro-oxidation of formic acid was studied in a direct-oxidation polymer-electrolyte fuel cell at 170 C using real-time mass spectrometry. The results are compared with those obtained for methanol oxidation under the same conditions. Formic acid was electrochemically more active than methanol on both Pt-black and Pt-Ru catalysts. The polarization potential of formic acid oxidation was ca. 90 to 100 mV lower than that of methanol. The oxidation of formic acid was dependent on the water/formic acid mole ratio. The best anode performance was obtained using a water/formic acid mole ratio of {approximately}2. In addition, Pt/Ru catalyst was more active than Pt-black for formic acid oxidation. The mass spectrometric results showed that CO{sub 2} is the only reaction product of formic acid oxidation. The results are discussed in terms of possible formic acid oxidation mechanisms.

Weber, M.; Wang, J.T.; Wasmus, S.; Savinell, R.F. [Case Western Reserve Univ., Cleveland, OH (United States)

1996-07-01T23:59:59.000Z

140

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

Science Conference Proceedings (OSTI)

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

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

Laser desorption/ionization mass spectrometry for direct profiling and imaging of small molecules from raw biological materials  

DOE Green Energy (OSTI)

Matrix-assisted laser desorption/ionization(MALDI) mass spectrometry(MS) has been widely used for analysis of biological molecules, especially macromolecules such as proteins. However, MALDI MS has a problem in small molecule (less than 1 kDa) analysis because of the signal saturation by organic matrixes in the low mass region. In imaging MS (IMS), inhomogeneous surface formation due to the co-crystallization process by organic MALDI matrixes limits the spatial resolution of the mass spectral image. Therefore, to make laser desorption/ionization (LDI) MS more suitable for mass spectral profiling and imaging of small molecules directly from raw biological tissues, LDI MS protocols with various alternative assisting materials were developed and applied to many biological systems of interest. Colloidal graphite was used as a matrix for IMS of small molecules for the first time and methodologies for analyses of small metabolites in rat brain tissues, fruits, and plant tissues were developed. With rat brain tissues, the signal enhancement for cerebroside species by colloidal graphite was observed and images of cerebrosides were successfully generated by IMS. In addition, separation of isobaric lipid ions was performed by imaging tandem MS. Directly from Arabidopsis flowers, flavonoids were successfully profiled and heterogeneous distribution of flavonoids in petals was observed for the first time by graphite-assisted LDI(GALDI) IMS.

Cha, Sangwon

2008-05-15T23:59:59.000Z

142

Deconstruction of Activity-Dependent Covalent Modification of Heme in Human Neutrophil Myeloperoxidase by Multistage Mass Spectrometry (MS[superscript 4])  

SciTech Connect

Myeloperoxidase (MPO) is known to be inactivated and covalently modified by treatment with hydrogen peroxide and agents similar to 3-(2-ethoxypropyl)-2-thioxo-2,3-dihydro-1H-purin-6(9H)-one (1), a 254.08 Da derivative of 2-thioxanthine. Peptide mapping by liquid chromatography and mass spectrometry detected modification by 1 in a labile peptide-heme-peptide fragment of the enzyme, accompanied by a mass increase of 252.08 Da. The loss of two hydrogen atoms was consistent with mechanism-based oxidative coupling. Multistage mass spectrometry (MS{sup 4}) of the modified fragment in an ion trap/Orbitrap spectrometer demonstrated that 1 was coupled directly to heme. Use of a 10 amu window delivered the full isotopic envelope of each precursor ion to collision-induced dissociation, preserving definitive isotopic profiles for iron-containing fragments through successive steps of multistage mass spectrometry. Iron isotope signatures and accurate mass measurements supported the structural assignments. Crystallographic analysis confirmed linkage between the methyl substituent of the heme pyrrole D ring and the sulfur atom of 1. The final orientation of 1 perpendicular to the plane of the heme ring suggested a mechanism consisting of two consecutive one-electron oxidations of 1 by MPO. Multistage mass spectrometry using stage-specific collision energies permits stepwise deconstruction of modifications of heme enzymes containing covalent links between the heme group and the polypeptide chain.

Geoghegan, Kieran F.; Varghese, Alison H.; Feng, Xidong; Bessire, Andrew J.; Conboy, James J.; Ruggeri, Roger B.; Ahn, Kay; Spath, Samantha N.; Filippov, Sergey V.; Conrad, Steven J.; Carpino, Philip A.; Guimarães, Cristiano R.W.; Vajdos, Felix F. (Pfizer)

2013-03-07T23:59:59.000Z

143

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.

Litvinov, Y A; Geissel, H; Weick, H; Beckert, Karl; Beller, Peter; Boutin, D; Brandau, C; Chen, L; Klepper, O; Knöbel, R; Kozhuharov, C; Kurcewicz, J; Litvinov, S A; Mazzocco, M; Münzenberg, G; Nociforo, C; Nolden, F; Plass, W; Scheidenberger, C; Steck, Markus; Sun, B; Winkler, M; Litvinov, Yu.A.

2005-01-01T23:59:59.000Z

144

Organic aerosol components observed in Northern Hemispheric datasets from Aerosol Mass Spectrometry  

E-Print Network (OSTI)

In this study we compile and present results from the factor analysis of 43 Aerosol Mass Spectrometer (AMS) datasets (27 of the datasets are reanalyzed in this work). The components from all sites, when taken together, ...

Kroll, Jesse

145

Elemental analysis of aerosol organic nitrates with electron ionization high-resolution mass spectrometry  

E-Print Network (OSTI)

Four hydroxynitrates (R(OH)R'ONO2) representative of atmospheric volatile organic compound (VOC) oxidation products were synthesized, nebulized and sampled into an Aerodyne High Resolution Time of Flight Aerosol Mass ...

Rollins, A. W.

146

The Particle Adventure | Accelerators and Particle Detectors  

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

Waves and particles The world's meterstick Mass and energy Energy-mass conversion Accelerators How to obtain particles to accelerate Accelerating particles Accelerating...

147

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

148

High-Resolution Electrospray Ionization Mass Spectrometry Analysis of Water- Soluble Organic Aerosols Collected with a Particle into Liquid Sampler  

DOE Green Energy (OSTI)

This work demonstrates the utility of a particle-into-liquid sampler (PILS) a technique traditionally used for identification of inorganic ions present in ambient or laboratory aerosols for the analysis of water soluble organic aerosol (OA) using high resolution electrospray ionization mass spectrometry (HR ESI-MS). Secondary organic aerosol (SOA) was produced from 0.5 ppm mixing ratios of limonene and ozone in a 5 m3 Teflon chamber. SOA was collected simultaneously using a traditional filter sampler and a PILS. The filter samples were later extracted with either water or acetonitrile, while the aqueous PILS samples were analyzed directly. In terms of peak intensities, types of detectable compounds, average O:C ratios, and organic mass to organic carbon ratios, the resulting high resolution mass spectra were essentially identical for the PILS and filter based samples. SOA compounds extracted from both filter/acetonitrile extraction and PILS/water extraction accounted for >95% of the total ion current in ESI mass spectra. This similarity was attributed to high solubility of limonene SOA in water. In contrast, significant differences in detected ions and peak abundances were observed for pine needle biomass burning organic aerosol (BBOA) collected with PILS and filter sampling. The water soluble fraction of BBOA is considerably smaller than for SOA, and a number of unique peaks were detectable only by the filter/acetonitrile method. The combination of PILS collection with HR-ESI-MS analysis offers a new approach for molecular analysis of the water-soluble organic fraction in biogenic SOA, aged photochemical smog, and BBOA.

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

2010-10-01T23:59:59.000Z

149

Mass spectrometry-based methods for detection and differentiation of botulinum neurotoxins  

DOE Patents (OSTI)

The present invention is directed to a method for detecting the presence of clostridial neurotoxins in a sample by mixing a sample with a peptide that can serve as a substrate for proteolytic activity of a clostridial neurotoxin; and measuring for proteolytic activity of a clostridial neurotoxin by a mass spectroscopy technique. In one embodiment, the peptide can have an affinity tag attached at two or more sites.

Schmidt, Jurgen G. (Los Alamos, NM); Boyer, Anne E. (Atlanta, GA); Kalb, Suzanne R. (Atlanta, GA); Moura, Hercules (Tucker, GA); Barr, John R. (Suwannee, GA); Woolfitt, Adrian R. (Atlanta, GA)

2009-11-03T23:59:59.000Z

150

Development of a detection method for {244}Pu by resonance ionization mass spectrometry.  

Science Conference Proceedings (OSTI)

The long-lived actinide {sup 244}Pu (t{sub 1/2} = 81 Myr) is expected to be present in the Interstellar Medium from fresh r-process nucleosynthesis or in direct ejecta from supernovae. Deposition onto Earth may result in traces of live {sup 244}Pu in suitable reservoirs. We are developing a method for {sup 244}Pu detection based on resonance ionization mass spectroscopy. Using Gd as a proxy, we determine an overall efficiency of 0.5% in conditions applicable to the detection of Pu, and present preliminary results on Pu detection.

Ofan, A.; Ahmad, I.; Greene, J. P.; Paul, M.; Savina, M. R. (Materials Science Division); ( PHY); (Hebrew Univ.)

2006-07-01T23:59:59.000Z

151

Enzymatic Digestion in Aqueous-Organic Solvents: A Mass Spectrometry-Based Approach in Monitoring Protein Conformation Changes  

E-Print Network (OSTI)

The three dimensional structure of a protein is important for its function. When misfolded, a protein may be rendered inactive or adapt a conformation that could be toxic. Studying protein folding requires an understanding of protein conformation. Traditionally, protein conformation has been studied using x-ray crystallography and nuclear magnetic resonance (NMR). X-ray crystallography is limited in the analysis of crystallized proteins and is computationally intensive. NMR deals with proteins in solution but reports only an average of conformation and the technique severely suffers from spectral overlapping due to the thousands of resonances of the protein. More recently, mass spectrometry has been employed not only to elucidate primary structures but also gather information on the three-dimensional conformation of proteins. In this study, a mass spectrometric-based approach is used to study the changes in conformation of cytochrome c and the green fluorescent protein when subjected to aqueous-organic solvent systems. The technique involved trypsin digestion and generation of peptide mass maps. For cytochrome c, the experiments were done with ethanol, methanol and acetonitrile to gain insights on naturation and denaturation. An apparent solvent effect to the rate of digestion and propensity for missed cleavages attributed to weakening of hydrophobic interactions and strengthening of intramolecular hydrogen bonding was observed. For the green fluorescent protein, sulfolane, a known supercharging agent, was used to gain insights on the effect of supercharging to protein conformation. Addition of 2.0% sulfolane shifted the charge state envelope of the protein towards lower m/z while adding lower amounts of sulfolane enhanced lower charge states while broadening the charge state envelope. The time course study showed different patterns of digestion dependent on solvent conditions implying changes in conformation. Furthermore, absorbance and fluorescence measurements suggested that addition of sulfolane protects the fluorophore from quenching. The activity of trypsin is not affected by addition of low amounts of sulfolane.

Tuvilla, Mavreen Rose

2013-05-01T23:59:59.000Z

152

Electrodeposition of Technetium on Platinum for Thermal Ionization Mass Spectrometry (TIMS)  

Science Conference Proceedings (OSTI)

A novel device has been fabricated for the electrodeposition of technetium metal onto platinum filaments for thermal ionization mass spectrometric (TIMS) measurements. The ability of the device to focus the deposition to diameters of hundreds of micrometers on pre-mounted TIMS filaments coupled with the ease of use and simplicity of design permit for an extremely sensitive yet economical TIMS filament loading technique. Electrodeposition parameters were varied in order to maximize deposition efficiency. X-ray photoelectron spectroscopy (XPS) was used to confirm and characterize the technetium deposit. The technetium is deposited in the metallic state, although surface oxides in the 4+ and 7+ state form readily. Initial TIMS measurements of the electrodeposited technetium in the presence of a barium sulfate ionization enhancer show potential for excellent sensitivity.

Engelmann, Mark D.; Metz, Lori A.; Delmore, James E.; Engelhard, Mark H.; Ballou, Nathan E.

2008-05-15T23:59:59.000Z

153

Single Particle Laser Mass Spectrometry Applied to Differential Ice Nucleation Experiments at the AIDA Chamber  

SciTech Connect

Experiments conducted at the Aerosol Interactions and Dynamics in the Atmosphere (AIDA) chamber located in Karlsruhe, Germany permit investigation of particle properties that affect the nucleation of ice at temperature and water vapor conditions relevant to cloud microphysics and climate issues. Ice clouds were generated by heterogeneous nucleation of Arizona test dust (ATD), illite, and hematite and homogeneous nucleation of sulfuric acid. Ice crystals formed in the chamber were inertially separated from unactivated, or ‘interstitial’ aerosol particles with a pumped counterflow virtual impactor (PCVI), then evaporated. The ice residue (i.e., the aerosol which initiated ice nucleation plus any material which was scavenged from the gas- and/or particle-phase), was chemically characterized at the single particle level using a laser ionization mass spectrometer. In this manner the species that first nucleated ice could be identified out of a mixed aerosol population in the chamber. Bare mineral dust particles were more effective ice nuclei (IN) than similar particles with a coating. Metallic particles from contamination in the chamber initiated ice nucleation before other species but there were few enough that they did not compromise the experiments. Nitrate, sulfate, and organics were often detected on particles and ice residue, evidently from scavenging of trace gas-phase species in the chamber. Hematite was a more effective ice nucleus than illite. Ice residue was frequently larger than unactivated test aerosol due to the formation of aggregates due to scavenging, condensation of contaminant gases, and the predominance of larger aerosol in nucleation.

Gallavardin, S. J.; Froyd, Karl D.; Lohmann, U.; Moehler, Ottmar; Murphy, Daniel M.; Cziczo, Dan

2008-08-26T23:59:59.000Z

154

Determination of total chlorine and bromine in solid wastes by sintering and inductively coupled plasma-sector field mass spectrometry  

Science Conference Proceedings (OSTI)

A sample preparation method based on sintering, followed by analysis by inductively coupled plasma-sector field mass spectrometry (ICP-SFMS) for the simultaneous determination of chloride and bromide in diverse and mixed solid wastes, has been evaluated. Samples and reference materials of known composition were mixed with a sintering agent containing Na{sub 2}CO{sub 3} and ZnO and placed in an oven at 560 deg. C for 1 h. After cooling, the residues were leached with water prior to a cation-exchange assisted clean-up. Alternatively, a simple microwave-assisted digestion using only nitric acid was applied for comparison. Thereafter the samples were prepared for quantitative analysis by ICP-SFMS. The sintering method was evaluated by analysis of certified reference materials (CRMs) and by comparison with US EPA Method 5050 and ion chromatography with good agreement. Median RSDs for the sintering method were determined to 10% for both chlorine and bromine, and median recovery to 96% and 97%, respectively. Limits of detection (LODs) were 200 mg/kg for chlorine and 20 mg/kg for bromine. It was concluded that the sintering method is suitable for chlorine and bromine determination in several matrices like sewage sludge, plastics, and edible waste, as well as for waste mixtures. The sintering method was also applied for determination of other elements present in anionic forms, such as sulfur, arsenic, selenium and iodine.

Osterlund, Helene [Division of Applied Geology, Lulea University of Technology, S-971 87 Lulea (Sweden); ALS Scandinavia AB, ALS Laboratory Group, Aurorum 10, S-977 75 Lulea (Sweden)], E-mail: Helene.Osterlund@alsglobal.com; Rodushkin, Ilia [Division of Applied Geology, Lulea University of Technology, S-971 87 Lulea (Sweden); ALS Scandinavia AB, ALS Laboratory Group, Aurorum 10, S-977 75 Lulea (Sweden); Ylinenjaervi, Karin; Baxter, Douglas C. [ALS Scandinavia AB, ALS Laboratory Group, Aurorum 10, S-977 75 Lulea (Sweden)

2009-04-15T23:59:59.000Z

155

Oxidative degradation of bis (2,4,4-trimethylpentyl) dithiophosphinic acid in nitric acid studied by electrospray ionization mass spectrometry  

SciTech Connect

Samples of bis(2,4,4-trimethylpentyl)dithiophosphinic acid (Cyanex-301) were analyzed using direct infusion electrospray ionization mass spectrometry. Positive ion spectra of standard and stereo-pure acids displayed ions typical of the unmodified compound, cationized monomeric and dimeric cluster ion species. In addition, a significant ions 2 u less than the dimeric clusters were seen, that correspond to an oxidatively coupled species designated Cyx2 that is observed as H- or Na-cationized species in the electrospray analyses. Based on uncorrected ion intensities, Cyx2 is estimated to account for about 20% of the total in the standard materials. When samples that were contacted with 3 M HNO3 were analyzed, the positive ion spectrum consisted nearly entirely of ions derived from the oxidatively coupled product, indicating that the acid promotes coupling. The negative ion spectra of the standard acids consisted nearly entirely of the conjugate base that is formed by deprotonation of the acids, and cluster ions containing multiple acid molecules. The negative spectra of the HNO3-contacted samples also contained the conjugate base of the unmodified acid, but also two other species that correspond to the dioxo- and perthio- derivatives. It is concluded that HNO3 contact causes significant oxidation, forming at least three major products, Cyx2, the perthio-acid, and the dioxo-acid.

G. S. Groenewold; D. R. Peterman

2012-10-01T23:59:59.000Z

156

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

Science Conference Proceedings (OSTI)

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

157

B American Society for Mass Spectrometry, 2011 DOI: 10.1007/s13361-011-0217-6  

E-Print Network (OSTI)

Abstract A new, two-dimensional overtone mobility spectrometry (OMS-OMS) instrument is described Spectrom. (2011) 22:2049Y2060 RESEARCH ARTICLE Overtone Mobility Spectrometry: Part 4. OMS-OMS Analyses for the analysis of complex peptide mixtures. OMS separations are based on the differences in mobilities of ions

Clemmer, David E.

158

B American Society for Mass Spectrometry, 2011 DOI: 10.1007/s13361-011-0087-y  

E-Print Network (OSTI)

Spectrom. (2011) 22:804Y816 RESEARCH ARTICLE Overtone Mobility Spectrometry: Part 3. On the Origin of Peaks The origin of non-integer overtone peaks in overtone mobility spectrometry (OMS) spectra is investigated of peaks. The new equation makes it possible to determine collision cross sections from any OMS peak

Clemmer, David E.

159

Fundamental studies of the plasma extraction and ion beam formation processes in inductively coupled plasma mass spectrometry  

SciTech Connect

The fundamental and practical aspects are described for extracting ions from atmospheric pressure plasma sources into an analytical mass spectrometer. Methodologies and basic concepts of inductively coupled plasma mass spectrometry (ICP-MS) are emphasized in the discussion, including ion source, sampling interface, supersonic expansion, slumming process, ion optics and beam focusing, and vacuum considerations. Some new developments and innovative designs are introduced. The plasma extraction process in ICP-MS was investigated by Langmuir measurements in the region between the skimmer and first ion lens. Electron temperature (T{sub e}) is in the range 2000--11000 K and changes with probe position inside an aerosol gas flow. Electron density (n{sub e}) is in the range 10{sup 8}--10{sup 10} {sup {minus}cm }at the skimmer tip and drops abruptly to 10{sup 6}--10{sup 8} cm{sup {minus}3} near the skimmer tip and drops abruptly to 10{sup 6}--10{sup 8} cm{sup {minus}3} downstream further behind the skimmer. Electron density in the beam leaving the skimmer also depends on water loading and on the presence and mass of matrix elements. Axially resolved distributions of electron number-density and electron temperature were obtained to characterize the ion beam at a variety of plasma operating conditions. The electron density dropped by a factor of 101 along the centerline between the sampler and skimmer cones in the first stage and continued to drop by factors of 10{sup 4}--10{sup 5} downstream of skimmer to the entrance of ion lens. The electron density in the beam expansion behind sampler cone exhibited a 1/z{sup 2} intensity fall-off (z is the axial position). An second beam expansion originated from the skimmer entrance, and the beam flow underwent with another 1/z{sup 2} fall-off behind the skimmer. Skimmer interactions play an important role in plasma extraction in the ICP-MS instrument.

Niu, Hongsen

1995-02-10T23:59:59.000Z

160

Interlaboratory Validation of EPA 1600 Series Methods: Draft EPA Method 1638 for Analysis of Metals in Water by Inductively Coupled Plasma -- Mass Spectrometry (ICP-MS)  

Science Conference Proceedings (OSTI)

Federal and state permits are requiring wastewater dischargers to monitor for ever lower concentrations of trace metals, in some cases at levels that may preclude reliable measurement. In this joint EPA-EPRI interlaboratory data collection effort, eight laboratories evaluated draft EPA Method 1638: Determination of Trace Elements in Ambient Water by Inductively Coupled Plasma-Mass Spectrometry. This method is intended for the analysis of low levels (parts per trillion) of antimony, cadmium, copper, lead,...

2000-11-27T23:59:59.000Z

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.


161

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

Science Conference Proceedings (OSTI)

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

162

Competitive fragmentation pathways of acetic acid dimer explored by synchrotron VUV photoionization mass spectrometry and electronic structure calculations  

Science Conference Proceedings (OSTI)

In present study, photoionization and dissociation of acetic acid dimers have been studied with the synchrotron vacuum ultraviolet photoionization mass spectrometry and theoretical calculations. Besides the intense signal corresponding to protonated cluster ions (CH{sub 3}COOH){sub n}{center_dot}H{sup +}, the feature related to the fragment ions (CH{sub 3}COOH)H{sup +}{center_dot}COO (105 amu) via {beta}-carbon-carbon bond cleavage is observed. By scanning photoionization efficiency spectra, appearance energies of the fragments (CH{sub 3}COOH){center_dot}H{sup +} and (CH{sub 3}COOH)H{sup +}{center_dot}COO are obtained. With the aid of theoretical calculations, seven fragmentation channels of acetic acid dimer cations were discussed, where five cation isomers of acetic acid dimer are involved. While four of them are found to generate the protonated species, only one of them can dissociate into a C-C bond cleavage product (CH{sub 3}COOH)H{sup +}{center_dot}COO. After surmounting the methyl hydrogen-transfer barrier 10.84 {+-} 0.05 eV, the opening of dissociative channel to produce ions (CH{sub 3}COOH){sup +} becomes the most competitive path. When photon energy increases to 12.4 eV, we also found dimer cations can be fragmented and generate new cations (CH{sub 3}COOH){center_dot}CH{sub 3}CO{sup +}. Kinetics, thermodynamics, and entropy factors for these competitive dissociation pathways are discussed. The present report provides a clear picture of the photoionization and dissociation processes of the acetic acid dimer in the range of the photon energy 9-15 eV.

Guan Jiwen; Hu Yongjun; Zou Hao [MOE Key laboratory of Laser Life Science and Institute of Laser Life Science, College of Biophotonics, South China Normal University, Guangzhou 510631 (China); Cao Lanlan; Liu Fuyi; Shan Xiaobin; Sheng Liusi [National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, Anhui 230029 (China)

2012-09-28T23:59:59.000Z

163

Measurement of {sup 63}Ni and {sup 59}Ni by accelerator mass spectrometry using characteristic projectile x-rays  

Science Conference Proceedings (OSTI)

The long-lived isotopes of nickel ({sup 59}Ni, {sup 63}Ni) have current and potential use in a number of applications including cosmic radiation studies, biomedical tracing, characterization of low-level radioactive wastes, and neutron dosimetry. Methods are being developed at LLNL for the routine detection of these isotopes by AMS. One intended application is in Hiroshima dosimetry. The reaction {sup 63}Cu(n,p){sup 63}Ni has been identified as one of a small number of reactions which might be used for the direct determination of the fast neutron fluence emitted by the Hiroshima bomb. AMS measurement of {sup 63}Ni(t{sub 1/2} = 100 y) requires the chemical removal of {sup 63}Cu, which is a stable isobar of {sup 63}Ni. Following the electrochemical separation of Ni from gram-sized copper samples, the Cu concentration is further lowered to Hiroshima hypocenter. For the demonstration samples, the Cu content was chemically reduced by a factor of 10{sup 12} with quantitative retention of {sup 63}Ni. Detection sensitivity (3{sigma}) was {approximately}20 fg {sup 63}Ni in 1 mg Ni carrier ({sup 63}Ni/Ni {approx} 2 x 10{sup -11}). Significant improvements in sensitivity are expected with planned incremental changes in the methods. Preliminary results indicate that a similar sensitivity is achievable for {sup 59}Ni (t{sub 1/2} = 10{sup 5} y).

McAninch, J.E.; Hainsworth, L.J.; Marchetti, A.A. [and others

1996-05-01T23:59:59.000Z

164

Measurement of {sup 63}Ni and {sup 59}Ni by accelerator mass spectrometry using characteristic projectile x-rays  

SciTech Connect

The long-lived isotopes of nickel ({sup 59}Ni, {sup 63}Ni) have current and potential use in a number of applications including cosmic radiation studies, biomedical tracing, characterization of low-level radioactive wastes, and neutron dosimetry. Methods are being developed at LLNL for the routine detection of these isotopes by AMS. One intended application is in Hiroshima dosimetry. The reaction {sup 63}Cu(n,p){sup 63}Ni has been identified as one of a small number of reactions which might be used for the direct determination of the fast neutron fluence emitted by the Hiroshima bomb. AMS measurement of {sup 63}Ni(t{sub 1/2} = 100 y) requires the chemical removal of {sup 63}Cu, which is a stable isobar of {sup 63}Ni. Following the electrochemical separation of Ni from gram-sized copper samples, the Cu concentration is further lowered to < 2 x 10{sup -8} (Cu/Ni) using the reaction of Ni with carbon monoxide to form the gas Ni(CO){sub 4}. The Ni(CO){sub 4} is thermally decomposed directly in sample holders for measurement by AMS. After analysis in the AMS spectrometer, the ions are identified using characteristic projectile x-rays, allowing further rejection of remaining {sup 63}Cu. In a demonstration experiment, {sup 63}Ni was measured in Cu wires (2-20 g) which had been exposed to neutrons from a {sup 252}Cf source. We successfully measured {sup 63}Ni at levels necessary for the measurement of Cu samples exposed near the Hiroshima hypocenter. For the demonstration samples, the Cu content was chemically reduced by a factor of 10{sup 12} with quantitative retention of {sup 63}Ni. Detection sensitivity (3{sigma}) was {approximately}20 fg {sup 63}Ni in 1 mg Ni carrier ({sup 63}Ni/Ni {approx} 2 x 10{sup -11}). Significant improvements in sensitivity are expected with planned incremental changes in the methods. Preliminary results indicate that a similar sensitivity is achievable for {sup 59}Ni (t{sub 1/2} = 10{sup 5} y).

McAninch, J.E.; Hainsworth, L.J.; Marchetti, A.A. [and others

1996-05-01T23:59:59.000Z

165

Characterization of human expired breath by solid phase microextraction and analysis using gas chromatography-mass spectrometry and differential mobility spectrometry  

E-Print Network (OSTI)

Breath analysis has potential to become a new medical diagnostic modality. In this thesis, a method for the analysis of human expired breath was developed using gas chromatography-mass spectroscopy. It was subsequently ...

Merrick, William (William F. W.)

2005-01-01T23:59:59.000Z

166

Nano-Domain Analysis Via Massive Cluster Secondary Ion Mass Spectrometry in the Event-by-Event Mode  

E-Print Network (OSTI)

Secondary ion mass spectrometry (SIMS) is a surface analysis technique which characterizes species sputtered by an energetic particle beam. Bombardment with cluster projectiles offers the following notable advantages over bombardment with atomic ions or small clusters: enhanced emission of molecular ions, low damage cross-section, and reduced molecular fragmentation. Additionally, in the case of Au4004 and C60 impacts, desorption originates from nanometric volumes. These features make clusters useful probes to obtain molecular information from both nano-objects and nano-domains. The "event-by-event bombardment/detection mode" probes nano-objects one-at-a-time, while collecting and storing the corresponding secondary ion (SI) information. Presented here are the first experiments where free-standing nano-objects were bombarded with keV projectiles of atomic to nanoparticle size. The objects are aluminum nano-whiskers, 2 nm in diameter and ~250 nm in length. Au4004 has a diameter of ~2 nm, comparable to the nominal diameter of the nanowhiskers. There are notable differences in the SI response from sample volumes too small for full projectile energy deposition. The whisker spectra are dominated by small clusters?the most abundant species being AlO- and AlO2-. Bulk samples have larger yields for AlO2- than for AlO-, while this trend is reversed in whisker samples. Bulk samples give similar abundances of large SI clusters, while whisker samples give an order of magnitude lower yield of these SIs. Effective yields were calculated in order to determine quantitative differences between the nano-objects and bulk samples. The characterization of individual nano-objects from a mixture is demonstrated with negatively charged polymer spheres that are attracted to and retained by the nano-whiskers. The spheres are monodisperse polystyrene nanoparticles (30nm diameter). Our results show that the event-by-event mode can provide information on the nature, size, relative location, and abundance of nano-objects in the field of view. This study presents the first evidence of quantitative molecular information originating from nano-object mixtures. Biologically relevant systems (solid-supported lipid bilayers) were also characterized using Au5 , Au4004 and C60 . Organization-dependent SI emission was observed for phosphocholine bilayers. Lipid domain formation was also investigated in bilayers formed from cholesterol and a mixed lipid system. Trends in the correlation coefficient suggest that cholesterol segregates from the surrounding lipid environment during raft formation.

Pinnick, Veronica Tiffany

2009-12-01T23:59:59.000Z

167

Mass inflation in a D dimensional Reissner-Nordstrom black hole: a hierarchy of particle accelerators ?  

E-Print Network (OSTI)

We study the geometry inside the event horizon of perturbed D dimensional Reissner-Nordstrom-(A)dS type black holes showing that, similarly to the four dimensional case, mass inflation also occurs for D>4. First, using the homogeneous approximation, we show that an increase of the number of spatial dimensions contributes to a steeper variation of the metric coefficients with the areal radius and that the phenomenon is insensitive to the cosmological constant in leading order. Then, using the code reported in arXiv:0904.2669 [gr-qc] adapted to D dimensions, we perform fully non-linear numerical simulations. We perturb the black hole with a compact pulse adapting the pulse amplitude such that the relative variation of the black hole mass is the same in all dimensions, and determine how the black hole interior evolves under the perturbation. We qualitatively confirm that the phenomenon is similar to four dimensions as well as the behaviour observed in the homogeneous approximation. We speculate about the formation of black holes inside black holes triggered by mass inflation, and about possible consequences of this scenario.

P. P. Avelino; A. J. S. Hamilton; C. A. R. Herdeiro; M. Zilhao

2011-05-23T23:59:59.000Z

168

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

169

EFFECTS OF PERPENDICULAR DIFFUSION ON ENERGETIC PARTICLES ACCELERATED BY THE INTERPLANETARY CORONAL MASS EJECTION SHOCK  

Science Conference Proceedings (OSTI)

In this work, based on a numerical solution of the focused transport equation, we obtained the intensity and anisotropy time profiles of solar energetic particles (SEPs) accelerated by an interplanetary shock in the three-dimensional Parker magnetic field. The shock is treated as a moving source of energetic particles with an assumed particle distribution function. We computed the time profiles of particle flux and anisotropy as measured by an observer at 1 AU, equatorial plane, and various longitudes with respect to the shock propagation direction. With perpendicular diffusion, energetic particles can cross magnetic field lines. Particles may be detected before the observer's field line is connected to the shock. After the observer's field line breaks from the shock front, the observer still can see more particles are injected into its field line. Our simulations show that the particle onset time, peak time, peak intensity, decay rate, and duration of SEP event could be significantly influenced by the effect of perpendicular diffusion. The anisotropy with perpendicular diffusion is almost the same as that without perpendicular diffusion, but there is an obvious difference at the moment when the observer's field line begins to be connected to the shock.

Wang, Y.; Qin, G. [State Key Laboratory of Space Weather, Center for Space Science and Applied Research, Chinese Academy of Sciences, Beijing 100190 (China); Zhang, M., E-mail: ywang@spaceweather.ac.cn, E-mail: gqin@spaceweather.ac.cn, E-mail: mzhang@fit.edu [Department of Physics and Space Sciences, Florida Institute of Technology, Melbourne, FL 32901 (United States)

2012-06-10T23:59:59.000Z

170

International Journal of Mass Spectrometry 309 (2012) 154160 Contents lists available at SciVerse ScienceDirect  

E-Print Network (OSTI)

.elsevier.com/locate/ijms Extracted fragment ion mobility distributions: A new method for complex mixture analysis Sunyoung Lee, Zhiyu isomers a b s t r a c t A new method is presented for constructing ion mobility distributions of precursor 2011 Available online 22 September 2011 Keywords: Ion mobility spectrometry Collision

Clemmer, David E.

171

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

172

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

E-Print Network (OSTI)

mass fractions in particles. Aerosol Science and Technology,mediated lung injury, J. Aerosol Sci. , 29 (5-6), 553-560,from natural to anthropogenic aerosol radiative forcing:

Spencer, Matthew Todd

2007-01-01T23:59:59.000Z

173

Laser ablation-inductively coupled plasma-mass spectrometry: Examinations of the origins of polyatomic ions and advances in the sampling of particulates  

SciTech Connect

This dissertation provides a general introduction to Inductively coupled plasma-mass spectrometry (ICP-MS) and laser ablation (LA) sampling, with an examination of analytical challenges in the employment of this technique. It discusses the origin of metal oxide ions (MO+) in LA-ICP-MS, as well as the effect of introducing helium and nitrogen to the aerosol gas flow on the formation of these polyatomic interferences. It extends the study of polyatomic ions in LA-ICP-MS to metal argide (MAr+) species, an additional source of possible significant interferences in the spectrum. It describes the application of fs-LA-ICP-MS to the determination of uranium isotope ratios in particulate samples.

Witte, Travis

2011-11-30T23:59:59.000Z

174

Determination of the {sup 22}Ne{sub nucl}/{sup 4}He{sub rad} ratio in natural uranium-rich fluorite by mass spectrometry  

Science Conference Proceedings (OSTI)

A determination by noble gas mass spectrometry of {sup 22}Ne production through the combined reactions {sup 19}F({alpha},n){sup 22}Na({beta}{sup +}){sup 22}Ne and {sup 19}F({alpha},p){sup 22}Ne on natural calcium fluoride is made for the first time. Six samples of U-rich fluorite from a fluorspar deposit in Mexico were used to determine the {sup 22}Ne{sub nucl}/{sup 4}He{sub rad} ratio generated by the spontaneous decay of U during the last 32 Ma. The obtained ratio (1.33 {+-} 0.11) x10{sup -5} (95% confidence), is compared to other experimental data on natural uranium oxides and theoretical values.

Sole, Jesus; Pi, Teresa [Instituto de Geologia, Universidad Nacional Autonoma de Mexico, Cd. Universitaria, Coyoacan, 04510 Mexico D.F. (Mexico)

2006-10-15T23:59:59.000Z

175

Multiplexed Ion Mobility Spectrometry-Orthogonal Time-of ...  

Multiplexed Ion Mobility Spectrometry-Orthogonal Time-of-Flight Mass Spectrometry Mikhail E. Belov, ... in the multiplexed IMS-TOF MS experiments ...

176

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 an electron ionization source, a quadrupole mass spectrometer, a uniform field drift cell spectrometer encased in a cryogenic envelope, and an orthogonal geometry time-of-flight mass spectrometer. The analytical benefits of low temperature ion mobility are discussed in terms of enhanced separation ability, ion selectivity and sensitivity. The distinction between resolving power and resolution for ion mobility is also discussed. Detailed experimental designs and rationales are provided for each instrument component. Tuning and calibration data and methods are also provided for the technique. Proof-of-concept experiments for an array of analytes including rare gases (argon, krypton, xenon), hydrocarbons (acetone, ethylene glycol, methanol), and halides (carbon tetrachloride) are provided in order to demonstrate the advantages and limitations of the instrument for obtaining analytically useful information. Trendline partitioning of small analyte ions based on chemical composition is demonstrated as a novel chemical analysis method. The utility of mobility-mass analysis for mass selected ions is also demonstrated, particularly for probing the ion chemistry which occurs in the drift tube for small mass ions. As a final demonstration of the separation abilities of the instrument, the electronic states of chromium and titanium (ground and excited) are separated with low temperature. The transition metal electronic state separations demonstrated here are at the highest resolution ever obtained for ion mobility methods. The electronic conformational mass isomers of methanol (conventional and distonic) are also partially separated at low temperature. Various drift gases (helium, neon, and argon) are explored for the methanol system in order to probe stronger ion-neutral interaction potentials and effectuate higher resolution separations of the two isomeric ions. Finally, two versatile ion source designs and a method for axially focusing ions at low pressure (1-10 torr) using electrostatic fields is presented along with some preliminary work on the ion sources.

May, Jody C.

2009-08-01T23:59:59.000Z

177

B American Society for Mass Spectrometry, 2011 DOI: 10.1007/s13361-011-0168-y  

E-Print Network (OSTI)

with collision-induced dissociation MS/MS. Anal. Sci. 25, 985­ 988 (2009) 15. Williams, J.P., Grabenauer, MHz). Periodically, ion packets are released in short (150 s-wide) pulses into a ~3 m long stacked ring) m/z measurement. Roughly 102 ­103 mass spectra are collected per IMS experiment, allowing drift time

Clemmer, David E.

178

Final Technical Report for DE-FG02-06ER15835: Chemical Imaging with 100nm Spatial Resolution: Combining High Resolution Flurosecence Microscopy and Ion Mobility Mass Spectrometry  

SciTech Connect

We have combined, in a single instrument, high spatial resolution optical microscopy with the chemical specificity and conformational selectivity of ion mobility mass spectrometry. We discuss the design and construction of this apparatus as well as our efforts in applying this technique to thin films of molecular semiconductor materials.

Buratto, Steven K. [UC Santa Barbara

2013-09-03T23:59:59.000Z

179

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

Science Conference Proceedings (OSTI)

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

180

Use of Proton-Transfer-Reaction Mass Spectrometry to Characterize Volatile Organic Compound Sources at the La Porte Super Site During the Texas Air Quality Study 2000  

SciTech Connect

Proton-transfer-reaction mass spectrometry (PTR-MS) was deployed for continuous real-time monitoring of volatile organic compounds (VOCs) at a site near the Houston Ship Channel during the Texas Air Quality Study 2000. Overall, 28 ions dominated the PTR-MS mass spectra and were assigned as anthropogenic aromatics (e.g., benzene, toluene, xylenes) and hydrocarbons (propene, isoprene), oxygenated compounds (e.g., formaldehyde, acetaldehyde, acetone, methanol, C7 carbonyls), and three nitrogencontaining compounds (e.g., HCN, acetonitrile and acrylonitrile). Biogenic VOCs were minor components at this site. Propene was the most abundant lightweight hydrocarbon detected by this technique with concentrations up to 100+ nmol mol-1, and was highly correlated with its oxidation products, formaldehyde (up to ~40 nmol mol-1) and acetaldehyde (up to ~80 nmol/mol), with typical ratios close to 1 in propene-dominated plumes. In the case of aromatic species the high time resolution of the obtained data set helped in identifying different anthropogenic sources (e.g., industrial from urban emissions) and testing current emission inventories. A comparison with results from complimentary techniques (gas chromatography, differential optical absorption spectroscopy) was used to assess the selectivity of this on-line technique in a complex urban and industrial VOC matrix and give an interpretation of mass scans obtained by ‘‘soft’’ chemical ionization using proton-transfer via H3O+. The method was especially valuable in monitoring rapidly changing VOC plumes which passed over the site, and when coupled with meteorological data it was possible to identify likely sources.

Karl, Thomas G.; Jobson, B Tom T.; Kuster, W. C.; Williams, Eric; Stutz, Jochen P.; Shetter, Rick; Hall, Samual R.; Goldan, P. D.; Fehsenfeld, Fred C.; Lindinger, Werner

2003-08-19T23:59:59.000Z

Note: This page contains sample records for the topic "accelerator mass spectrometry" from the National Library of EnergyBeta (NLEBeta).
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to obtain the most current and comprehensive results.


181

Feasibility of the detection of trace elements in particulate matter using online High-Resolution Aerosol Mass Spectrometry  

SciTech Connect

The feasibility of using an online thermal-desorption electron-ionization high-resolution aerosol mass spectrometer (AMS) for the detection of particulate trace elements was investigated analyzing data from Mexico City obtained during the MILAGRO 2006 field campaign, where relatively high concentrations of trace elements have been reported. This potential application is of interest due to the real-time data provided by the AMS, its high sensitivity and time resolution, and the widespread availability and use of this instrument. High resolution mass spectral analysis, isotopic ratios, and ratios of different ions containing the same elements are used to constrain the chemical identity of the measured ions. The detection of Cu, Zn, As, Se, Sn, and Sb is reported. There was no convincing evidence for the detection of other trace elements commonly reported in PM. The elements detected tend to be those with lower melting and boiling points, as expected given the use of a vaporizer at 600oC in this instrument. Operation of the AMS vaporizer at higher temperatures is likely to improve trace element detection. The detection limit is estimated at approximately 0.3 ng m-3 for 5-min of data averaging. Concentration time series obtained from the AMS data were compared to concentration records determined from offline analysis of particle samples from the same times and locations by ICP (PM2.5) and PIXE (PM1.1 and PM0.3). The degree of correlation and agreement between the three instruments (AMS, ICP, and PIXE) varied depending on the element. The AMS shows promise for real-time detection of some trace elements, although additional work including laboratory calibrations with different chemical forms of these elements are needed to further develop this technique and to understand the differences with the ambient data from the other techniques. The trace elements peaked in the morning as expected for primary sources, and the many detected plumes suggest the presence of multiple point sources, probably industrial, in Mexico City which are variable in time and space, in agreement with previous studies.

Salcedo, D.; Laskin, Alexander; Shutthanandan, V.; Jimenez, Jose L.

2012-08-10T23:59:59.000Z

182

Isotope ratio analysis of actinides, fission products, and geolocators by high-efficiency multi-collector thermal ionization mass spectrometry  

SciTech Connect

A ThermoFisher 'Triton' multi-collector thermal ionization mass spectrometer (MC-TIMS) was evaluated for trace and ultra-trace level isotoperatioanalysis of actinides (uranium, plutonium, and americium), fission products and geolocators (strontium, cesium, and neodymium). Total efficiencies (atoms loaded to ions detected) of up to 0.5-2% for U, Pu, and Am, and 1-30% for Sr, Cs, and Nd can be reported employing resin bead load techniques onto flat ribbon Re filaments or resin beads loaded into a millimeter-sized cavity drilled into a Re rod. This results in detection limits of <0.1 fg (10{sup 4} atoms to 10{sup 5} atoms) for {sup 239-242+244}Pu, {sup 233+236}U, {sup 241-243}Am, {sup 89,90}Sr, and {sup 134,135,137}Cs, and {le} 1 pg for natural Nd isotopes (limited by the chemical processing blank) using a secondary electron multiplier (SEM) or multiple-ion counters (MICs). Relative standard deviations (RSD) as small as 0.1% and abundance sensitivities of 1 x 10{sup 6} or better using a SEM are reported here. Precisions of RSD {approx} 0.01-0.001% using a multi-collector Faraday cup array can be achieved at sub-nanogram concentrations for strontium and neodymium and are suitable to gain crucial geolocation information. The analytical protocols reported herein are of particular value for nuclear forensic and nuclear safeguard applications.

Bürger, Stefan [New Brunswick Laboratory, Argonne, IL; Riciputi, Lee R [Los Alamos National Laboratory (LANL); Bostick, Debra A [ORNL; Turgeon, Steven [University of Alberta, Edmondton, Canada; McBay, Eddie H [ORNL; Lavelle, Mark [ORNL

2009-01-01T23:59:59.000Z

183

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

Science Conference Proceedings (OSTI)

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

184

Analysis of Non-Enzymatically Glycated Peptides: Neutral-Loss Triggered MS3 Versus Multi-Stage Activation Tandem Mass Spectrometry  

Science Conference Proceedings (OSTI)

Non-enzymatic glycation of tissue proteins has important implications in the development of complications of diabetes mellitus. While electron transfer dissociation (ETD) has been shown to outperform collision-induced dissociation (CID) in sequencing glycated peptides by tandem mass spectrometry, ETD instrumentation is not yet available in all laboratories. In this study, we evaluated different advanced CID techniques (i.e., neutral-loss triggered MS3 and multi-stage activation) during LC-MSn analyses of Amadori-modified peptides enriched from human serum glycated in vitro. During neutral-loss triggered MS3 experiments, MS3 scans triggered by neutral-losses of 3 H2O or 3 H2O + HCHO produced similar results in terms of glycated peptide identifications. However, neutral losses of 3 H2O resulted in significantly more glycated peptide identifications during multi-stage activation experiments. Overall, the multi-stage activation approach produced more glycated peptide identifications, while the neutral-loss triggered MS3 approach resulted in much higher specificity. Both techniques offer a viable alternative to ETD for identifying glycated peptides when that method is unavailable.

Zhang, Qibin; Petyuk, Vladislav A.; Schepmoes, Athena A.; Orton, Daniel J.; Monroe, Matthew E.; Yang, Feng; Smith, Richard D.; Metz, Thomas O.

2008-10-15T23:59:59.000Z

185

Design and performance of a combined secondary ion mass spectrometry-scanning probe microscopy instrument for high sensitivity and high-resolution elemental three-dimensional analysis  

Science Conference Proceedings (OSTI)

State-of-the-art secondary ion mass spectrometry (SIMS) instruments allow producing 3D chemical mappings with excellent sensitivity and spatial resolution. Several important artifacts however arise from the fact that SIMS 3D mapping does not take into account the surface topography of the sample. In order to correct these artifacts, we have integrated a specially developed scanning probe microscopy (SPM) system into a commercial Cameca NanoSIMS 50 instrument. This new SPM module, which was designed as a DN200CF flange-mounted bolt-on accessory, includes a new high-precision sample stage, a scanner with a range of 100 {mu}m in x and y direction, and a dedicated SPM head which can be operated in the atomic force microscopy (AFM) and Kelvin probe force microscopy modes. Topographical information gained from AFM measurements taken before, during, and after SIMS analysis as well as the SIMS data are automatically compiled into an accurate 3D reconstruction using the software program 'SARINA,' which was developed for this first combined SIMS-SPM instrument. The achievable lateral resolutions are 6 nm in the SPM mode and 45 nm in the SIMS mode. Elemental 3D images obtained with our integrated SIMS-SPM instrument on Al/Cu and polystyrene/poly(methyl methacrylate) samples demonstrate the advantages of the combined SIMS-SPM approach.

Wirtz, Tom; Fleming, Yves; Gerard, Mathieu [Department 'Science and Analysis of Materials' (SAM), Centre de Recherche Public, Gabriel Lippmann, 41 rue du Brill, L-4422 Belvaux (Luxembourg); Gysin, Urs; Glatzel, Thilo; Meyer, Ernst [Department of Physics, Universitaet Basel, Klingelbergstrasse 82, CH-4056 Basel (Switzerland); Wegmann, Urs [Department of Physics, Universitaet Basel, Klingelbergstrasse 82, CH-4056 Basel (Switzerland); Ferrovac GmbH, Thurgauerstr. 72, CH-8050 Zuerich (Switzerland); Maier, Urs [Ferrovac GmbH, Thurgauerstr. 72, CH-8050 Zuerich (Switzerland); Odriozola, Aitziber Herrero; Uehli, Daniel [SPECS Zurich GmbH, Technoparkstr. 1, CH-8005 Zuerich (Switzerland)

2012-06-15T23:59:59.000Z

186

Detection and Identification of Heme c-Modified Peptides by Histidine Affinity Chromatography, High-Performance Liquid Chromatography-Mass Spectrometry, and Database Searching  

Science Conference Proceedings (OSTI)

Multiheme c-type cytochromes (proteins with covalently attached heme c moieties) play important roles in extracellular metal respiration in dissimilatory metal-reducing bacteria. Liquid chromatography-tandem mass spectrometry-(LC-MS/MS) characterization of c-type cytochromes is hindered by the presence of multiple heme groups, since the heme c modified peptides are typically not observed, or if observed, not identified. Using a recently reported histidine affinity chromatography (HAC) procedure, we enriched heme c tryptic peptides from purified bovine heart cytochrome c, a bacterial decaheme cytochrome, and subjected these samples to LC-MS/MS analysis. Enriched bovine cytochrome c samples yielded three- to six-fold more confident peptide-spectrum matches to heme-c containing peptides than unenriched digests. In unenriched digests of the decaheme cytochrome MtoA from Sideroxydans lithotrophicus ES-1, heme c peptides for four of the ten expected sites were observed by LC-MS/MS; following HAC fractionation, peptides covering nine out of ten sites were obtained. Heme c peptide spiked into E. coli lysates at mass ratios as low as 10-4 was detected with good signal-to-noise after HAC and LC-MS/MS analysis. In addition to HAC, we have developed a proteomics database search strategy that takes into account the unique physicochemical properties of heme c peptides. The results suggest that accounting for the double thioether link between heme c and peptide, and the use of the labile heme fragment as a reporter ion, can improve database searching results. The combination of affinity chromatography and heme-specific informatics yielded increases in the number of peptide-spectrum matches of 20-100-fold for bovine cytochrome c.

Merkley, Eric D.; Anderson, Brian J.; Park, Jea H.; Belchik, Sara M.; Shi, Liang; Monroe, Matthew E.; Smith, Richard D.; Lipton, Mary S.

2012-12-07T23:59:59.000Z

187

Detection of triclocarban and two co-contaminating chlorocarbanilides in US aquatic environments using isotope dilution liquid chromatography tandem mass spectrometry  

SciTech Connect

The antimicrobial compound triclocarban (TCC; 3,4,4'-trichlorocarbanilide; CAS-bar 101-20-2) is a high-production-volume chemical, recently suggested to cause widespread contamination of US water resources. To test this hypothesis, we developed an isotope dilution liquid chromatography electrospray ionization tandem mass spectrometry method for ultratrace analysis of TCC (0.9ng/L detection limit) and analyzed low-volume water samples (200mL) along with primary sludge samples from across the United States. All river water samples (100%) collected downstream of wastewater treatment plants had detectable levels of TCC, as compared to 56% of those taken upstream. Concentrations of TCC (mean+/-standard deviation) downstream of sewage treatment plants (84+/-110ng/L) were significantly higher (P<0.05; Wilcoxon rank sum test) than those of samples taken upstream (12+/-15ng/L). Compared to surface water, mean TCC concentrations found in dried, primary sludge obtained from municipal sewage treatment plants in five states were six orders of magnitude greater (19,300+/-7100{mu}g/kg). Several river samples contained a co-contaminant, identified based on its chromatographic retention time, molecular base ion, and MS/MS fragmentation behavior as 4,4'-dichlorocarbanilide (DCC; CAS-bar 1219-99-4). In addition to TCC and DCC, municipal sludge contained a second co-contaminant, 3,3',4,4'-tetrachlorocarbanilide (TetraCC; CAS-bar 4300-43-0). Both newly detected compounds were present as impurities (0.2%{sub w/w} each) in technical grade TCC (99%). Application of the new method for chlorocarbanilide analysis yielded TCC occurrence data for 13 US states, confirmed the role of sewage treatment plants as environmental inputs of TCC, and identified DCC and TetraCC as previously unrecognized pollutants released into the environment alongside TCC.

Sapkota, Amir [Department of Environmental Health Sciences, Johns Hopkins University, Bloomberg School of Public Health, Johns Hopkins University Center for Water and Health, Baltimore, MD 21205-2103 (United States); Heidler, Jochen [Department of Environmental Health Sciences, Johns Hopkins University, Bloomberg School of Public Health, Johns Hopkins University Center for Water and Health, Baltimore, MD 21205-2103 (United States); Halden, Rolf U. [Department of Environmental Health Sciences, Johns Hopkins University, Bloomberg School of Public Health, Johns Hopkins University Center for Water and Health, Baltimore, MD 21205-2103 (United States)]. E-mail: rhalden@jhsph.edu

2007-01-15T23:59:59.000Z

188

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

E-Print Network (OSTI)

Separations coupled to mass spectrometry (MS) are widely used for large-scale protein identification in order to reduce the adverse effects of analyte ion suppression, increase the dynamic range, and as a deconvolution technique for complex datasets typical of cellular protein complements. In this work, matrix assisted laser desorption-ionization is coupled with ion mobility (IM) separation for the analysis of biological molecules. The utility of liquid-phase separations coupled to MS lies in the orthogonality of the two separation dimensions for all analytes. The data presented in this work illustrates that IM-MS relies on the correlation between separation dimensions for different classes (either structural or chemical) of analyte ions to obtain a useful separation. For example, for a series of peptide ions of increasing mass-to-charge (m/z) a plot drift time in the IM drift cell vs. m/z increases in a near-linear fashion, but DNA or lipids having similar m/z values will have very different IM drift time-m/z relationships, thus drift time vs. m/z can be used as a qualitative tool for compound class identification. In addition, IM-MS is applied to the analysis of large peptide datasets in order to determine the peak capacity of the method for bottom-up experiments in proteomics, and it is found that IM separation increases the peak capacity of an MS-only experiment by a factor of 5-10. The population density of the appearance area for peptides is further characterized in terms of the gas-phase structural propensities for tryptic peptide ions. It is found that a small percentage (~3%) of peptide sequences form extended (i.e., helical or ?-sheet type) structures in the gas-phase, thus influencing the overall appearance area for peptide ions. Furthermore, the ability of IM-MS to screen for the presence of phosphopeptides is characterized, and it is found that post translationally modified peptides populate the bottom one-half to one-third of the total appearance area for peptide ions. In general, the data presented in this work indicates that IM-MS offers dynamic range and deconvolution capabilities comparable to liquid-phase separation techniques coupled to MS on a time scale (ms) that is fully compatible to current MS, including TOF-MS, technology.

Ruotolo, Brandon Thomas

2003-05-01T23:59:59.000Z

189

Synergistic use of Knudsen effusion quadrupole mass spectrometry, solid-state galvanic cell and differential scanning calorimetry for thermodynamic studies on lithium aluminates  

SciTech Connect

Three ternary oxides LiAl{sub 5}O{sub 8}(s), LiAlO{sub 2}(s) and Li{sub 5}AlO{sub 4}(s) in the system Li-Al-O were prepared by solid-state reaction route and characterized by X-ray powder diffraction method. Equilibrium partial pressure of CO{sub 2}(g) over the three-phase mixtures {l_brace}LiAl{sub 5}O{sub 8}(s)+Li{sub 2}CO{sub 3}(s)+5Al{sub 2}O{sub 3}(s){r_brace}, {l_brace}LiAl{sub 5}O{sub 8}(s)+5LiAlO{sub 2}(s)+2Li{sub 2}CO{sub 3}(s){r_brace} and {l_brace}LiAlO{sub 2}(s)+Li{sub 5}AlO{sub 4}(s)+2Li{sub 2}CO{sub 3}(s){r_brace} were measured using Knudsen effusion quadrupole mass spectrometry (KEQMS). Solid-state galvanic cell technique based on calcium fluoride electrolyte was used to determine the standard molar Gibbs energies of formations of these aluminates. The standard molar Gibbs energies of formation of these three aluminates calculated from KEQMS and galvanic cell measurements were in good agreement. Heat capacities of individual ternary oxides were measured from 127 to 868 K using differential scanning calorimetry. Thermodynamic tables representing the values of {delta}{sub f}H{sup 0}(298.15 K), S{sup 0}(298.15 K) S{sup 0}(T), C{sub p}{sup 0}(T), H{sup 0}(T), {l_brace}H{sup 0}(T)-H{sup 0}(298.15 K){r_brace}, G{sup 0}(T), {delta}{sub f}H{sup 0}(T), {delta}{sub f}G{sup 0}(T) and free energy function (fef) were constructed using second law analysis and FACTSAGE thermo-chemical database software. - Graphical abstract: Comparison of {delta}{sub f}G{sub m}{sup 0} of ternary oxides determined from KEQMS and solid-state galvanic cell techniques. (O) KEQMS, (9632;) solid-state galvanic cell and solid line: combined fit of both the experimental data.

Rakshit, S.K. [Product Development Section, Radiochemistry and Isotope Group, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India)], E-mail: swarupkr@barc.gov.in; Naik, Y.P.; Parida, S.C.; Dash, Smruti; Singh, Ziley; Sen, B.K.; Venugopal, V. [Product Development Section, Radiochemistry and Isotope Group, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India)

2008-06-15T23:59:59.000Z

190

Development and analytical validation of a gas chromatography-mass spectrometry method for the assessment of gastrointestinal permeability and intestinal absorptive capacity in dogs  

E-Print Network (OSTI)

Assessment of gastrointestinal permeability in vivo is considered a suitable method for the evaluation of gastrointestinal mucosal integrity. Probes commonly used include lactulose (L) and rhamnose (R) for the assessment of intestinal permeability, xylose (X) and 3-O-methylglucose (M) for the evaluation of intestinal absorptive capacity, and sucrose (S) for the assessment of gastric permeability. Traditionally, various methods have been used to quantify these markers in the urine after orogastric administration. However, urine collection is difficult and uncomfortable. A protocol based on the analysis of blood samples would be easier to perform. Thus, the aim of the first part of this project was to develop and validate a new gas chromatography-mass spectrometry (GC-MS) method for the quantification of five sugar probes in canine serum. The method was sensitive, accurate, precise, and reproducible for the simultaneous quantification of 5 sugar probes in serum. The aim of the second part of this project was to assess the kinetic profiles of these 5 sugar probes in serum after orogastric administration in dogs and to determine the optimal time point for sample collection. Dogs received a solution containing L (10 g/L), R (10 g/L), X (10 g/L), M (5 g/L), and S (40 g/L) by orogastric intubation. Baseline blood samples were collected. Subsequent timed blood samples were taken for a 24 hours period. Significant changes in serum concentrations of all 5 sugars were detected after administration of the test dose (p<0.0001 for all 5 probes). Serum concentrations of L and R were significantly different from baseline concentrations from 90 to 240 and from 60 to 300 min post dosing respectively, and those of X, M, and S were significantly different from 30 to 240 min after dosing (p<0.05 for all 5 probes). Variations of the mean sugar concentrations of all dogs at 90, 120, and 180 minutes were analyzed using a Kruskal-Wallis test. Based on the results, only two blood samples, one taken at baseline and a second sample obtained between 90 and 180 after dosing, appear to be sufficient for assessment of intestinal permeability and mucosal absorptive capacity using these sugar probes.

Rodriguez Frausto, Heriberto

2008-12-01T23:59:59.000Z

191

Technical Basis Document: A Statistical Basis for Interpreting Urinary Excretion of Plutonium Based on Accelerator Mass Spectrometry (AMS) for Selected Atoll Populations in the Marshall Islands  

SciTech Connect

We have developed refined statistical and modeling techniques to assess low-level uptake and urinary excretion of plutonium from different population group in the northern Marshall Islands. Urinary excretion rates of plutonium from the resident population on Enewetak Atoll and from resettlement workers living on Rongelap Atoll range from <1 to 8 {micro}Bq per day and are well below action levels established under the latest Department regulation 10 CFR 835 in the United States for in vitro bioassay monitoring of {sup 239}Pu. However, our statistical analyses show that urinary excretion of plutonium-239 ({sup 239}Pu) from both cohort groups is significantly positively associated with volunteer age, especially for the resident population living on Enewetak Atoll. Urinary excretion of {sup 239}Pu from the Enewetak cohort was also found to be positively associated with estimates of cumulative exposure to worldwide fallout. Consequently, the age-related trends in urinary excretion of plutonium from Marshallese populations can be described by either a long-term component from residual systemic burdens acquired from previous exposures to worldwide fallout or a prompt (and eventual long-term) component acquired from low-level systemic intakes of plutonium associated with resettlement of the northern Marshall Islands, or some combination of both.

Bogen, K; Hamilton, T F; Brown, T A; Martinelli, R E; Marchetti, A A; Kehl, S R; Langston, R G

2007-05-01T23:59:59.000Z

192

Technical Basis Document: A Statistical Basis for Interpreting Urinary Excretion of Plutonium Based on Accelerator Mass Spectrometry (AMS) for Selected Atoll Populations in the Marshall Islands  

Science Conference Proceedings (OSTI)

We have developed refined statistical and modeling techniques to assess low-level uptake and urinary excretion of plutonium from different population group in the northern Marshall Islands. Urinary excretion rates of plutonium from the resident population on Enewetak Atoll and from resettlement workers living on Rongelap Atoll range from fallout. Consequently, the age-related trends in urinary excretion of plutonium from Marshallese populations can be described by either a long-term component from residual systemic burdens acquired from previous exposures to worldwide fallout or a prompt (and eventual long-term) component acquired from low-level systemic intakes of plutonium associated with resettlement of the northern Marshall Islands, or some combination of both.

Bogen, K; Hamilton, T F; Brown, T A; Martinelli, R E; Marchetti, A A; Kehl, S R; Langston, R G

2007-05-01T23:59:59.000Z

193

ACCELERATION RESPONSIVE SWITCH  

DOE Patents (OSTI)

An acceleration-responsive device with dual channel capabilities whereby a first circuit is actuated upon attainment of a predetermined maximum acceleration level and when the acceleration drops to a predetermined minimum acceleriltion level another circuit is actuated is described. A fluid-damped sensing mass slidably mounted in a relatively frictionless manner on a shaft through the intermediation of a ball bushing and biased by an adjustable compression spring provides inertially operated means for actuating the circuits. (AEC)

Chabrek, A.F.; Maxwell, R.L.

1963-07-01T23:59:59.000Z

194

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

195

PARTICLE ACCELERATOR  

DOE Patents (OSTI)

ABS>A combination of two accelerators, a cyclotron and a ring-shaped accelerator which has a portion disposed tangentially to the cyclotron, is described. Means are provided to transfer particles from the cyclotron to the ring accelerator including a magnetic deflector within the cyclotron, a magnetic shield between the ring accelerator and the cyclotron, and a magnetic inflector within the ring accelerator.

Teng, L.C.

1960-01-19T23:59:59.000Z

196

Can Accelerators Accelerate Learning?  

Science Conference Proceedings (OSTI)

The 'Young Talented' education program developed by the Brazilian State Funding Agency (FAPERJ)[1] makes it possible for high-schools students from public high schools to perform activities in scientific laboratories. In the Atomic and Molecular Physics Laboratory at Federal University of Rio de Janeiro (UFRJ), the students are confronted with modern research tools like the 1.7 MV ion accelerator. Being a user-friendly machine, the accelerator is easily manageable by the students, who can perform simple hands-on activities, stimulating interest in physics, and getting the students close to modern laboratory techniques.

Santos, A. C. F.; Fonseca, P.; Coelho, L. F. S. [Instituto de Fisica, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil, Caixa Postal 68528, 21941-972 (Brazil)

2009-03-10T23:59:59.000Z

197

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.

198

PARTICLE ACCELERATOR  

DOE Patents (OSTI)

A fixed-field alternating gradient accelerator for simultaneous acceleration of two particle beams in opposite directions is described. (T.R.H.)

Ohkawa, T.

1959-06-01T23:59:59.000Z

199

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

200

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

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201

Mexico City Aerosol Analysis During Milagro Using High Resolution Aerosol Mass Spectrometry at the Urban Supersite (T0) - Part 1: Fine Particle Composition and Organic Source Apportionment.  

E-Print Network (OSTI)

Submicron aerosol was analyzed during the MILAGRO field campaign in March 2006 at the T0 urban supersite in Mexico City with a High-Resolution Aerosol Mass Spectrometer (AMS) and complementary instrumentation. Positive ...

Aiken, A. C.

202

Acceleration Mechanisms  

E-Print Network (OSTI)

Glossary I. Background and context of the subject II. Stochastic acceleration III. Resonant scattering IV. Diffusive shock acceleration V. DSA at multiple shocks VI. Applications of DSA VII. Acceleration by parallel electric fields VIII. Other acceleration mechanisms IX. Future directions X. Appendix: Quasilinear equations XI. Bibliography

Melrose, D B

2009-01-01T23:59:59.000Z

203

Decomposition of NH3BH3 at sub-ambient pressures: A combined thermogravimetry-differential thermal analysis-mass spectrometry study  

DOE Green Energy (OSTI)

We report a systematic study of the isothermal decomposition of ammonia borane, NH3BH3, at 363 K as a function of argon pressure ranging between 50 and 1040 mbar using thermogravimetry and differential thermal analysis coupled with mass analysis of the volatile species. During thermal aging at 363 K, evolution of hydrogen, aminoborane and borazine is monitored, with the relative mass loss strongly depending on the pressure in the reaction chamber. Furthermore, the induction period required for hydrogen release at 363 K decreases with decreasing pressure.

Palumbo, Oriele; Paolone, Annalisa; Rispoli, Pasquale; Cantelli, Rosario; Autrey, Thomas

2010-03-15T23:59:59.000Z

204

HEAVY ION LINEAR ACCELERATOR  

DOE Patents (OSTI)

A linear accelerator of heavy ions is described. The basic contributions of the invention consist of a method and apparatus for obtaining high energy particles of an element with an increased charge-to-mass ratio. The method comprises the steps of ionizing the atoms of an element, accelerating the resultant ions to an energy substantially equal to one Mev per nucleon, stripping orbital electrons from the accelerated ions by passing the ions through a curtain of elemental vapor disposed transversely of the path of the ions to provide a second charge-to-mass ratio, and finally accelerating the resultant stripped ions to a final energy of at least ten Mev per nucleon.

Van Atta, C.M.; Beringer, R.; Smith, L.

1959-01-01T23:59:59.000Z

205

New constraints on methane fluxes and rates of anaerobic methane oxidation in a Gulf of Mexico brine pool via in situ mass spectrometry  

E-Print Network (OSTI)

New constraints on methane fluxes and rates of anaerobic methane oxidation in a Gulf of Mexico Keywords: Methane flux Mass spectrometer Brine pool Methane oxidation Gulf of Mexico a b s t r a c t Deep report direct measurements of methane concentrations made in a Gulf of Mexico brine pool located

Girguis, Peter R.

206

High-Throughput Proteomics Using High Efficiency Multiple-Capillary Liquid Chromatography With On-Line High-Performance ESI FTICR Mass Spectrometry  

Science Conference Proceedings (OSTI)

We report on the design and application of a high-efficiency multiple-capillary liquid chromatography (LC) system for high-throughput proteome analysis. The multiple-capillary LC system was operated at the pressure of 10,000 psi using commercial LC pumps to deliver the mobile phase and newly developed passive feedback valves to switch the mobile phase flow and introduce samples. The multiple-capillary LC system was composed of several serially connected dual-capillary column devices. The dual-capillary column approach was designed to eliminate the time delay for regeneration (or equilibrium) of the capillary column after its use under the mobile phase gradient condition (i.e. one capillary column was used in separation and the other was washed using mobile phase A). The serially connected dual-capillary columns and ESI sources were operated independently, and could be used for either''backup'' operation or with other mass spectrometer(s). This high-efficiency multiple-capillary LC system uses switching valves for all operations and is highly amenable to automation. The separations efficiency of dual-capillary column device, optimal capillary dimensions (column length and packed particle size), suitable mobile phases for electrospray, and the capillary re-generation were investigated. A high magnetic field (11.5 tesla) Fourier transform ion cyclotron resonance (FTICR) mass spectrometer was coupled on-line with this high-efficiency multiple-capillary LC system through an electrospray ionization source. The capillary LC provided a peak capacity of {approx}600, and the 2-D capillary LC-FTICR provided a combined resolving power of > 6 x 10 7 polypeptide isotopic distributions. For yeast cellular tryptic digests, > 100,000 polypeptides were typically detected, and {approx}1,000 proteins can be characterized in a single run.

Shen, Yufeng (BATTELLE (PACIFIC NW LAB)); Tolic, Nikola (BATTELLE (PACIFIC NW LAB)); Zhao, Rui (ASSOC WESTERN UNIVERSITY); Pasa Tolic, Ljiljana (BATTELLE (PACIFIC NW LAB)); Li, Lingjun (Illinois Univ Of-Urbana/Champa); Berger, Scott J. (ASSOC WESTERN UNIVERSITY); Harkewicz, Richard (BATTELLE (PACIFIC NW LAB)); Anderson, Gordon A. (BATTELLE (PACIFIC NW LAB)); Belov, Mikhail E. (BATTELLE (PACIFIC NW LAB)); Smith, Richard D. (BATTELLE (PACIFIC NW LAB))

2000-12-01T23:59:59.000Z

207

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

Science Conference Proceedings (OSTI)

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

208

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

209

Accelerator Need  

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Need for Large Accelerators An Article Written Originally for Midlevel Teachers Back In order to study small particles, a high energy beam of particles must be generated. The...

210

Proton acceleration experiments with Z-Petawatt.  

Science Conference Proceedings (OSTI)

The outline of this presentation: (1) Proton acceleration with high-power lasers - Target Normal Sheath Acceleration concept; (2) Proton acceleration with mass-reduced targets - Breaking the 60 MeV threshold; (3) Proton beam divergence control - Novel focusing target geometry; and (4) New experimental capability development - Proton radiography on Z.

Arefiev, A. (University of Texas at Austin); Schaumann, G. (Technische Universitat Darmstadt, Germany); Deppert, O. (Technische Universitat Darmstadt, Germany); Rambo, Patrick K.; Roth, M. (Technische Universitat Darmstadt, Germany); Geissel, Matthias; Schwarz, Jens; Sefkow, Adam B.; Atherton, Briggs W.; Kimmel, Mark W.; Schollmeier, Marius; Breizman, B. (University of Texas at Austin)

2010-08-01T23:59:59.000Z

211

SLAC National Accelerator Laboratory - Accelerators and Society  

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

Accelerators and Society PHOTO: An accelerator at SLAC. SLAC has been developing, running and studying the basic physics of particle accelerators for half a century. Thousands of...

212

SLAC National Accelerator Laboratory - Accelerator Directorate  

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

physics. Today, the Accelerator Directorate operates and maintains SLAC's existing accelerators to provide the highest possible level of performance. Accelerator employees improve...

213

3D Molecular Bioimaging Mass Spectrometry  

Science Conference Proceedings (OSTI)

... ion images as a function of increasing depth during dynamic SIMS sputtering of ... used which in turn allows for higher sputtering rates, faster analysis ...

2012-10-02T23:59:59.000Z

214

Improving gene annotation using peptide mass spectrometry  

E-Print Network (OSTI)

Tanner, Zhouxin Shen, Julio Ng, Liliana Florea, Roderic1,6 Zhouxin Shen, 2 Julio Ng, 1 Liliana Florea, 3 Roderic

2007-01-01T23:59:59.000Z

215

Improved Ambient Ionization Source for Mass Spectrometry ...  

Pacific Northwest National Laboratory Skip to Main Content U.S. Department of Energy. Search PNNL. PNNL Home; About; Research; Publications; Jobs; ...

216

ION ACCELERATOR  

DOE Patents (OSTI)

An arrangement for the drift tubes in a linear accelerator is described whereby each drift tube acts to shield the particles from the influence of the accelerating field and focuses the particles passing through the tube. In one embodiment the drift tube is splii longitudinally into quadrants supported along the axis of the accelerator by webs from a yoke, the quadrants. webs, and yoke being of magnetic material. A magnetic focusing action is produced by energizing a winding on each web to set up a magnetic field between adjacent quadrants. In the other embodiment the quadrants are electrically insulated from each other and have opposite polarity voltages on adjacent quadrants to provide an electric focusing fleld for the particles, with the quadrants spaced sufficienily close enough to shield the particles within the tube from the accelerating electric field.

Bell, J.S.

1959-09-15T23:59:59.000Z

217

LINEAR ACCELERATOR  

DOE Patents (OSTI)

Improvements in linear particle accelerators are described. A drift tube system for a linear ion accelerator reduces gap capacity between adjacent drift tube ends. This is accomplished by reducing the ratio of the diameter of the drift tube to the diameter of the resonant cavity. Concentration of magnetic field intensity at the longitudinal midpoint of the external sunface of each drift tube is reduced by increasing the external drift tube diameter at the longitudinal center region.

Christofilos, N.C.; Polk, I.J.

1959-02-17T23:59:59.000Z

218

Long term activation in a 15 MeV radiotherapy accelerator  

SciTech Connect

The high energy electrons produced by linear accelerators can generate several radioisotopes by means of photonuclear reactions. The activity produced in the head of a 15 MV Mevatron Siemens 77 medical linear accelerator was measured by high resolution gamma-ray spectrometry, during its decommissioning 1 year after the last clinical use. The activity of {sup 54}Mn, {sup 57}Co, {sup 60}Co, {sup 181}W, and {sup 65}Zn was measured while the activity of other radioisotopes which emit soft {beta} or {gamma} rays such as {sup 59}Ni, {sup 63}Ni, and {sup 55}Fe was inferred by appropriate scaling factors. The number of pieces requiring particular care is limited, their mass does not exceed some tens of kilograms, and their volume is of the order of some thousands of cm{sup 3}. Moreover, these materials are metals and the emitted radiation can be easily shielded, so that storage should not create particular problems.

Brusa, A.; Cesana, A.; Stucchi, C.; Terrani, M.; Zanellati, F. [Health Physics Department, National Cancer Institute of Milan, Milan 20133 (Italy); Nuclear Engineering Department, Politecnico di Milano, Milan 20133 (Italy); Health Physics Department, National Cancer Institute of Milan, Milan 20133 (Italy); Nuclear Engineering Department, Politecnico di Milano, Milan 20133 (Italy); Health Physics Department, National Cancer Institute of Milan, Milan 20133 (Italy)

2008-07-15T23:59:59.000Z

219

Application Acceleration  

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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

220

Investigation of the effect of intra-molecular interactions on the gas-phase conformation of peptides as probed by ion mobility-mass spectrometry, gas-phase hydrogen/deuterium exchange, and molecular mechanics  

E-Print Network (OSTI)

Ion mobility-mass spectrometry (IM-MS), gas-phase hydrogen/deuterium (H/D) exchange ion molecule reactions and molecular modeling provide complimentary information and are used here for the characterization of peptide ion structure, including fine structure detail (i.e., cation-? interactions, ?-turns, and charge solvation interactions). IM-MS experiments performed on tyrosine containing tripeptides show that the collision cross-sections of sodiated, potassiated and doubly sodiated species of gly-gly-tyr are smaller than that of the protonated species, while the cesiated and doubly cesiated species are larger. Conversely, all of the alkali-adducted species of try-gly-gly have collision cross-sections that are larger than that of the protonated species. The protonated and alkali metal ion adducted (Na+, K+ and Cs+) species of bradykinin and bradykinin fragments 1-5, 1-6, 1-7, 1-8, 2-7, 5-9 and 2-9 were also studied using IM-MS and the alkali metal ion adducts of these species were found to have cross-sections very close to those of the protonated species. Additionally, multiple peak features observed in the ATDs of protonated bradykinin fragments 1-5, 1-6 and 1-7 are conserved upon alkali metal ion adduction. It was observed from gas-phase H/D ion molecule reactions that alkali adducted species exchange slower and to a lesser extent than protonated species in the tyrosine- and arginine-containing peptides. Experimental and computational results are discussed in terms of peptide ion structure, specifically the intra-molecular interactions present how those interactions change upon alkali salt adduction, as well as with the sequence of the peptide. Additionally, IM-MS data suggests the presence of a compact conformation of bradykinin fragment 1-5 (RPPGF) when starting from organic solvent conditions. As water is added stepwise to methanolic solutions, a more extended conformation is populated. When the starting solution is composed of ?90% water, two distinct mobility profiles are observed as well as a shoulder, indicating the presence of three gas-phase conformations for RPPGF. Gas-phase H/D exchange of [M+H]+ ions prepared from aqueous solvents show a bi-exponential decay, whereas samples prepared from organic solvents show a single exponential decay. The effect of solvent on gas-phase peptide ion structure, i.e., solution-phase memory effects, is discussed and gas-phase structures are compared to know solution-phase structures.

Sawyer, Holly Ann

2004-12-01T23:59:59.000Z

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.


221

JOURNAL OF MASS SPECTROMETRY J. Mass Spectrom. 2008; 43: 11611180  

E-Print Network (OSTI)

the rapid addition of energy to a condensed-phase sample (e.g. heat, photons, droplet or gas impact) results/ionization techniques in use with MS (Fig. 1). Introduced in the mid-1970s, commercially available in the 1980s. In this approach to surface sampling, heat is used to liberate the sample intact from the condensed phase

222

Compact accelerator  

DOE Patents (OSTI)

A compact linear accelerator having at least one strip-shaped Blumlein module which guides a propagating wavefront between first and second ends and controls the output pulse at the second end. Each Blumlein module has first, second, and third planar conductor strips, with a first dielectric strip between the first and second conductor strips, and a second dielectric strip between the second and third conductor strips. Additionally, the compact linear accelerator includes a high voltage power supply connected to charge the second conductor strip to a high potential, and a switch for switching the high potential in the second conductor strip to at least one of the first and third conductor strips so as to initiate a propagating reverse polarity wavefront(s) in the corresponding dielectric strip(s).

Caporaso, George J. (Livermore, CA); Sampayan, Stephen E. (Manteca, CA); Kirbie, Hugh C. (Los Alamos, NM)

2007-02-06T23:59:59.000Z

223

MUON ACCELERATION  

Science Conference Proceedings (OSTI)

One of the major motivations driving recent interest in FFAGs is their use for the cost-effective acceleration of muons. This paper summarizes the progress in this area that was achieved leading up to and at the FFAG workshop at KEK from July 7-12, 2003. Much of the relevant background and references are also given here, to give a context to the progress we have made.

BERG,S.J.

2003-11-18T23:59:59.000Z

224

What is an accelerator?  

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

world of physics though, 'accelerator' means something a little more specific. Our accelerators are a whole class of machines that accelerate atoms, or more often, pieces of...

225

Argonne Accelerator Institute  

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

Argonne Accelerator Institute: Mission The mission of the Argonne Accelerator Institute is centered upon the following related goals: Locate next generation accelerator facilities...

226

Review of ion accelerators  

Science Conference Proceedings (OSTI)

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

227

SLAC National Accelerator Laboratory - Accelerator Research  

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

An image of the FACET equipment and a man examining it. ACCELERATOR PHYSICS Accelerators form the backbone of SLAC's on-site experimental program. They are complicated...

228

Accelerators and the Accelerator Community  

Science Conference Proceedings (OSTI)

In this paper, standing back--looking from afar--and adopting a historical perspective, the field of accelerator science is examined. How it grew, what are the forces that made it what it is, where it is now, and what it is likely to be in the future are the subjects explored. Clearly, a great deal of personal opinion is invoked in this process.

Malamud, Ernest; Sessler, Andrew

2008-06-01T23:59:59.000Z

229

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

230

Resolving Emissions Dynamics via Mass Spectrometry: Time Resolved Measurements of Emission Transients by Mass Spectrometry  

DOE Green Energy (OSTI)

Transient emissions occur throughout normal engine operation and can significantly contribute to overall system emissions. Such transient emissions may originate from various sources including cold start, varying load and exhaust-gas recirculation (EGR) rates; all of which are dynamic processes in the majority of engine operation applications (1). Alternatively, there are systems which are inherently dynamic even at steady-state engine-operation conditions. Such systems include catalytic exhaust-emissions treatment devices with self-initiated and sustained oscillations (2) and NOX adsorber systems (3,4,5). High-speed diagnostics, capable of temporally resolving such emissions transients, are required to characterize the process, verify calculated system inputs, and optimize the system.

Partridge, William P.

2000-08-20T23:59:59.000Z

231

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

232

Acceleration Modules in Linear Induction Accelerators  

E-Print Network (OSTI)

Linear Induction Accelerator (LIA) is a unique type of accelerator, which is capable to accelerate kiloAmpere charged particle current to tens of MeV energy. The present development of LIA in MHz busting mode and successful application into synchrotron broaden LIAs usage scope. Although transformer model is widely used to explain the acceleration mechanism of LIAs, it is not appropriate to consider the induction electric field as the field which accelerates charged particles for many modern LIAs. Authors examined the transition of the magnetic cores functions during LIA acceleration modules evolution, distinguished transformer type and transmission line type LIA acceleration modules, and reconsidered several related issues based on transmission line type LIA acceleration module. The clarified understanding should be helpful in the further development and design of the LIA acceleration modules.

Wang, Shaoheng

2013-01-01T23:59:59.000Z

233

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)

234

Science Accelerator Widget  

Office of Scientific and Technical Information (OSTI)

Science Accelerator Widget You can now explore multiple Science Accelerator features through the new tabbed widget. Download this tool via the 'Get Widget Options' link or by...

235

Argonne Accelerator Institute  

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

Accelerators at Argonne Argonne has a long and continuing history of participation in accelerator based, and user oriented facilities. The Zero-Gradient Synchrotron, which began...

236

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

237

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

238

NIST MIRF - Accelerator Radiation Physics  

Science Conference Proceedings (OSTI)

Accelerator Radiation Physics. Medium-energy accelerators are under investigation for production of channeling radiation ...

239

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

240

SLAC National Accelerator Laboratory - SLAC National Accelerator...  

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

Security Notice and Terms of Use Updated January 3, 2005 PRIVACY NOTICE Welcome to the SLAC National Accelerator Laboratory website. We collect no personal information about you...

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

Increasing Confidence of LC-MS Identifications by Utilizing Ion Mobility Spectrometry  

SciTech Connect

Ion mobility spectrometry in conjunction with liquid chromatography separations and mass spectrometry offers a range of new possibilities for analyzing complex biological samples. To fully utilize the information obtained from these three measurement dimensions, informatics tools based on the accurate mass and time tag methodology were modified to incorporate ion mobility spectrometry drift times for peptides observed in human serum. A reference human serum database was created using 12,139 peptides, tracking the monoisotopic mass, liquid chromatography normalized elution time, and ion mobility spectrometry drift time(s) for each peptide. We demonstrate that the use of three dimensions for peak matching during the peptide identification process resulted in increased numbers of identifications and lower false discovery rates relative to the use of only the mass and normalized elution time dimensions.

Crowell, Kevin L.; Baker, Erin Shammel; Payne, Samuel H.; Ibrahim, Yehia M.; Monroe, Matthew E.; Slysz, Gordon W.; Lamarche, Brian L.; Petyuk, Vladislav A.; Piehowski, Paul D.; Danielson, William F.; Anderson, Gordon A.; Smith, Richard D.

2013-09-05T23:59:59.000Z

242

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

243

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

244

Argonne Accelerator Institute  

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

GEM - GeV Electron Microtron (design report 1982) The GEM design report describes a novel six-sided CW microtron for accelerating electrons to 4 GeV. This accelerator design was...

245

Accelerating Electric Vehicle Deployment | Department of Energy  

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

Accelerating Electric Vehicle Deployment Accelerating Electric Vehicle Deployment Accelerating Electric Vehicle Deployment Accelerating Electric Vehicle Deployment More Documents &...

246

Far field acceleration  

SciTech Connect

Far fields are propagating electromagnetic waves far from their source, boundary surfaces, and free charges. The general principles governing the acceleration of charged particles by far fields are reviewed. A survey of proposed field configurations is given. The two most important schemes, Inverse Cerenkov acceleration and Inverse free electron laser acceleration, are discussed in detail.

Fernow, R.C.

1995-07-01T23:59:59.000Z

247

What is an accelerator operator?  

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

is an accelerator operator? First I'll explain the education one must have in order to be considered for an Accelerator Operator position. Jefferson Lab's typical Accelerator...

248

Neutrino mass, a status report  

SciTech Connect

Experimental approaches to neutrino mass include kinematic mass measurements, neutrino oscillation searches at rectors and accelerators, solar neutrinos, atmospheric neutrinos, and single and double beta decay. The solar neutrino results yield fairly strong and consistent indications that neutrino oscillations are occurring. Other evidence for new physics is less consistent and convincing.

Robertson, R.G.H.

1993-08-01T23:59:59.000Z

249

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

250

SLAC National Accelerator Laboratory - Director of Accelerator...  

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

Committee on Appropriations asked the US Department of Energy (DOE) to submit a strategic plan for accelerator R&D by June 2012. The DOE asked me to lead a task force to...

251

High brightness electron accelerator  

DOE Patents (OSTI)

A compact high brightness linear accelerator is provided for use, e.g., in a free electron laser. The accelerator has a first plurality of acclerating cavities having end walls with four coupling slots for accelerating electrons to high velocities in the absence of quadrupole fields. A second plurality of cavities receives the high velocity electrons for further acceleration, where each of the second cavities has end walls with two coupling slots for acceleration in the absence of dipole fields. The accelerator also includes a first cavity with an extended length to provide for phase matching the electron beam along the accelerating cavities. A solenoid is provided about the photocathode that emits the electrons, where the solenoid is configured to provide a substantially uniform magnetic field over the photocathode surface to minimize emittance of the electrons as the electrons enter the first cavity.

Sheffield, R.L.; Carlsten, B.E.; Young, L.M.

1992-12-31T23:59:59.000Z

252

Acceleration in astrophysics  

SciTech Connect

The origin of cosmic rays and applicable laboratory experiments are discussed. Some of the problems of shock acceleration for the production of cosmic rays are discussed in the context of astrophysical conditions. These are: The presumed unique explanation of the power law spectrum is shown instead to be a universal property of all lossy accelerators; the extraordinary isotropy of cosmic rays and the limited diffusion distances implied by supernova induced shock acceleration requires a more frequent and space-filling source than supernovae; the near perfect adiabaticity of strong hydromagnetic turbulence necessary for reflecting the accelerated particles each doubling in energy roughly 10{sup 5} to {sup 6} scatterings with negligible energy loss seems most unlikely; the evidence for acceleration due to quasi-parallel heliosphere shocks is weak. There is small evidence for the expected strong hydromagnetic turbulence, and instead, only a small number of particles accelerate after only a few shock traversals; the acceleration of electrons in the same collisionless shock that accelerates ions is difficult to reconcile with the theoretical picture of strong hydromagnetic turbulence that reflects the ions. The hydromagnetic turbulence will appear adiabatic to the electrons at their much higher Larmor frequency and so the electrons should not be scattered incoherently as they must be for acceleration. Therefore the electrons must be accelerated by a different mechanism. This is unsatisfactory, because wherever electrons are accelerated these sites, observed in radio emission, may accelerate ions more favorably. The acceleration is coherent provided the reconnection is coherent, in which case the total flux, as for example of collimated radio sources, predicts single charge accelerated energies much greater than observed.

Colgate, S.A.

1993-12-31T23:59:59.000Z

253

A support vector machine model for the prediction of proteotypic peptides for accurate mass and time proteomics  

Science Conference Proceedings (OSTI)

Motivation: The standard approach to identifying peptides based on accurate mass and elution time (AMT) compares profiles obtained from a high resolution mass spectrometer to a database of peptides previously identified from tandem mass spectrometry ...

Bobbie-Jo M. Webb-Robertson; William R. Cannon; Christopher S. Oehmen; Anuj R. Shah; Vidhya Gurumoorthi; Mary S. Lipton; Katrina M. Waters

2010-07-01T23:59:59.000Z

254

A support vector machine model for the prediction of proteotypic peptides for accurate mass and time proteomics  

Science Conference Proceedings (OSTI)

Motivation: The standard approach to identifying peptides based on accurate mass and elution time (AMT) compares profiles obtained from a high resolution mass spectrometer to a database of peptides previously identified from tandem mass spectrometry ...

Bobbie-Jo M. Webb-Robertson; William R. Cannon; Christopher S. Oehmen; Anuj R. Shah; Vidhya Gurumoorthi; Mary S. Lipton; Katrina M. Waters

2008-07-01T23:59:59.000Z

255

Results from the RACE (Ring ACceleration Experiment) Compact Torus Acceleration Experiment  

DOE Green Energy (OSTI)

RACE (Ring ACceleration Experiment) is a proof-of-principle experiment aimed at demonstrating acceleration of magnetically confined compact torus plasma rings to directed kinetic energies well in excess of their magnetic and thermal energies. In the course of the first year of operation the following have been observed: successful formation of rings in the RACE geometry; acceleration of rings with large forces, F/sub accelerate/ approx.F/sub equilibrium/ without apparent degradation of the ring structure; peak velocities of approx. =2.5 x 10/sup 8/ cm/sec; acceleration efficiency of >30% at speeds of 1.5 x 10/sup 8/ cm/sec inferred from trajectory and capacitor bank data; kinetic to magnetic energy ratios approx.10 were observed. Experiments in the near future will be aimed at confirmation of the mass/energy measurements by calorimetry and direct density measurements.

Hammer, J.H.; Hartman, C.W.; Eddleman, J.L.; Kusse, B.

1987-06-01T23:59:59.000Z

256

A post accelerator for the U.S. rare isotope accelerator facility.  

SciTech Connect

The proposed Rare Isotope Accelerator (RIA) Facility includes a post-accelerator for rare isotopes (RIB linac) which must produce high-quality beams of radioactive ions over the full mass range, including uranium, at energies above the coulomb barrier, and have high transmission and efficiency. The latter requires the RIB linac to accept at injection ions in the 1+ charge state. A concept for such a post accelerator suitable for ions up to mass 132 has been previously described [1]. This paper presents a modified concept which extends the mass range to uranium. A high resolution separator for purifying beams at the isobaric level precedes the RIB linac. The mass filtering process will provide high purity beams while preserving transmission. For most cases a resolution of about m/{Delta}m=20,000 is adequate at mass A=100 to obtain a separation between isobars of mass excess difference of 5 MeV. The design for a device capable of purifying beams at the isobaric level included calculations up to 5th order. The RIB linac will utilize existing superconducting heavy-ion linac technology for all but a small portion of the accelerator system. The exceptional piece, a very-low-charge-state injector, section needed for just the first few MV of the RIB accelerator, consists of a pre-buncher followed by several sections of cw, normally-conducting RFQ. Two stages of charge stripping are provided: helium gas stripping at energies of a few keV/u, and additional foil stripping at {approx}680 keV/u for the heavier ions. In extending the mass range to uranium, however, for best efficiency the helium gas stripping must be performed at different energies for different mass ions. We present numerical simulations of the beam dynamics of a design for the complete RIB linac which provides for several stripping options and uses cost-effective solenoid focusing elements in the drift-tube linac.

Ostroumov, P. N.; Kelly, M. P.; Kolomiets, A. A.; Nolen, J. A.; Portillo, M.; Shepard, K. W.; Vinogradov, N. E.

2002-06-11T23:59:59.000Z

257

The History of Nuclidic Masses and of their Evaluation  

E-Print Network (OSTI)

This paper is centered on some historical aspects of nuclear masses, and their relations to major discoveries. Besides nuclear reactions and decays, the heart of mass measurements lies in mass spectrometry, the early history of which will be reviewed first. I shall then give a short history of the mass unit which has not always been defined as one twelfth of the carbon-12 mass. When combining inertial masses from mass spectrometry with energy differences obtained in reactions and decays, the conversion factor between the two is essential. The history of the evaluation of the nuclear masses (actually atomic masses) is only slightly younger than that of the mass measurements themselves. In their modern form, mass evaluations can be traced back to 1955. Prior to 1955, several tables were established, the oldest one in 1935.

G. Audi

2006-02-08T23:59:59.000Z

258

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

259

BNL | Accelerator Test Facility  

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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

260

Argonne Accelerator Institute  

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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

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While these samples are representative of the content of NLEBeta,
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to obtain the most current and comprehensive results.


261

North Linear Accelerator  

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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

262

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

263

High-energy accelerator for beams of heavy ions  

DOE Patents (OSTI)

An apparatus for accelerating heavy ions to high energies and directing the accelerated ions at a target comprises a source of singly ionized heavy ions of an element or compound of greater than 100 atomic mass units, means for accelerating the heavy ions, a storage ring for accumulating the accelerated heavy ions and switching means for switching the heavy ions from the storage ring to strike a target substantially simultaneously from a plurality of directions. In a particular embodiment the heavy ion that is accelerated is singly ionized hydrogen iodide. After acceleration, if the beam is of molecular ions, the ions are dissociated to leave an accelerated singly ionized atomic ion in a beam. Extraction of the beam may be accomplished by stripping all the electrons from the atomic ion to switch the beam from the storage ring by bending it in magnetic field of the storage ring.

Martin, Ronald L. (La Grange, IL); Arnold, Richard C. (Chicago, IL)

1978-01-01T23:59:59.000Z

264

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

265

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

266

Science Accelerator : User Account  

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Energy Office of Science Office of Scientific and Technical Information Website PoliciesImportant Links Science Accelerator science.gov WorldWideScience.org Deep Web Technologies...

267

Argonne Accelerator Institute  

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

ICFA Beam Dynamics Mini-Workshop on DeflectingCrabbing Cavity Applications in Accelerators April 21-23, 2010, Cockcroft Institute, Daresbury Laboratory, Warrington, UK Sixth...

268

Argonne Accelerator Institute  

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

Welcome Accelerators at Argonne Mission Organization History Document Collection Conferences & Workshops Beams and Applications Seminar Argonne-Fermilab Collaboration Lee Teng...

269

Human Accelerator - Teacher Overview  

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

electrons. The cavities are arranged in two long, straight sections called Linear Accelerators. In this activity, students pass tennis balls down a line like Jefferson Lab's...

270

Argonne Accelerator Institute  

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

(1971). (Located in the Argonne Research Library) Lee Teng Autobiography: Accelerators and I, Beam Dynamics Newsletter, No. 35, p 8-19, December (2004). (Located in Beam...

271

Market Acceleration (Fact Sheet)  

DOE Green Energy (OSTI)

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

272

Argonne Accelerator Institute  

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

- Document Access Guide ATLAS: A Proposal for a Precision Heavy Ion Accelerator, Argonne National Laboratory, February (1978). (Located in the DOE Information Bridge) The...

273

Argonne Accelerator Institute  

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

Fermilab Collaboration Lee Teng Scholarship Program Useful Links Argonne Accelerator Institute: For Industrial Collaborators -- Working with Argonne This link is addressed to...

274

The Accelerator Chain  

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

Watch video of Fermilab's Accelerators to learn more. Project Contact: Thomas Jordan - jordant@fnal.gov Web Maintainer: qnet-webmaster@fnal.gov Last Update: April 22, 2001...

275

WIPP - CBFO Accelerating Cleanup  

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

more information, access DOE Environmental Management site at: http:www.em.doe.govclosure For more information regarding the Accelerating Cleanup: Paths to Closure, contact...

276

Acceleration of polarized protons in circular accelerators  

SciTech Connect

The theory of depolarization in circular accelerators is presented. The spin equation is first expressed in terms of the particle orbit and then converted to the equivalent spinor equation. The spinor equation is then solved for three different situations: (1) a beam on a flat top near a resonance, (2) uniform acceleration through an isolated resonance, and (3) a model of a fast resonance jump. Finally, the depolarization coefficient, epsilon, is calculated in terms of properties of the particle orbit and the results are applied to a calculation of depolarization in the AGS.

Courant, E.D.; Ruth, R.D.

1980-09-12T23:59:59.000Z

277

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

278

Molecular-Beam Mass-Spectrometric Analyses of Hydrocarbon Flames.  

E-Print Network (OSTI)

??Laminar flat flame combustion has been studied with molecular-beam mass-spectrometry (MBMS) for a fuel-rich cyclohexane (? = 2.003) flame, a fuel-lean toluene (? = 0.895),… (more)

Gon, Saugata

2008-01-01T23:59:59.000Z

279

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

280

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.

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

Rotating charged black holes accelerated by an electric field  

E-Print Network (OSTI)

The Ernst method of removing nodal singularities from the charged C-metric representing uniformly accelerated black holes with mass $m$, charge $q$ and acceleration $A$ by "adding" an electric field $E$ is generalized. Utilizing the new form of the C-metric found recently, Ernst's simple "equilibrium" condition $mA=qE$ valid for small accelerations is generalized for arbitrary $A$. The nodal singularity is removed also in the case of accelerating and rotating charged black holes, and the corresponding equilibrium condition is determined.

Jiri Bicak; David Kofron

2010-06-21T23:59:59.000Z

282

Mass Spectrometry of Synthetic-Polymer Mixtures Workshop  

Science Conference Proceedings (OSTI)

... is held at constant total energy), changes in ... combining his continuum model theory with molecular ... than that found by nuclear magnetic resonance. ...

2013-09-30T23:59:59.000Z

283

OBT Measurement of Vegetation by Mass Spectrometry and Radiometry  

Science Conference Proceedings (OSTI)

Environmental and Organically Bound Tritium / Proceedings of the Ninth International Conference on Tritium Science and Technology (Part 2)

T. Tamari; H. Kakiuchi; N. Momoshima; N. Baglan; S. Sugihara; T. Uda

284

High-Sensitivity Ion Mobility Spectrometry/Mass ...  

... Bowers, M. T.; Kemper, P. R.; von Helden, G.; van Koppen, P. A. M. Science 1993, 260, 1446 ... (£), which results in large ion ... and R d is the ...

285

Quantification of neptunium by isotope dilution mass spectrometry  

SciTech Connect

A surface ionization-diffusion-type ionization source that uses a rhenium filament overplated with platinum has been developed and optimized for 0.1-ng neptunium samples. This source is capable of measuring the neptunium content of nuclear-test-debris samples to 0.15% precision at the 95% confidence level. 14 refs., 3 figs., 3 tabs.

Efurd, D.W.; Drake, J.; Roensch, F.R.; Cappis, J.H.; Perrin, R.E.

1986-05-01T23:59:59.000Z

286

Mass spectrometry of nuclear materials; Attention to detail  

SciTech Connect

Measurements of the {sup 235}U/{sup 238}U ratio in product-quality material have improved from uncertainties of 0.1 percent (rel) to 0.2 percent since the Manhattan Project. The hardware and procedural changes responsible for these measurement improvements are traced and discussed.

Shields, W.R

1989-11-01T23:59:59.000Z

287

Applications of Ionic Clusters in High Resolution Mass Spectrometry  

E-Print Network (OSTI)

of the ions by blackbody radiation or collisions withcathode heated due to blackbody radiation from the cell andby absorption of blackbody radiation, the precursor ions

Leib, Ryan David

2010-01-01T23:59:59.000Z

288

Spatially resolved thermal desorption/ionization coupled with mass spectrometry  

DOE Patents (OSTI)

A system and method for sub-micron analysis of a chemical composition of a specimen are described. The method includes providing a specimen for evaluation and a thermal desorption probe, thermally desorbing an analyte from a target site of said specimen using the thermally active tip to form a gaseous analyte, ionizing the gaseous analyte to form an ionized analyte, and analyzing a chemical composition of the ionized analyte. The thermally desorbing step can include heating said thermally active tip to above 200.degree. C., and positioning the target site and the thermally active tip such that the heating step forms the gaseous analyte. The thermal desorption probe can include a thermally active tip extending from a cantilever body and an apex of the thermally active tip can have a radius of 250 nm or less.

Jesse, Stephen; Van Berkel, Gary J; Ovchinnikova, Olga S

2013-02-26T23:59:59.000Z

289

Secondary Ion Mass Spectrometry of Vapor-Liquid-Solid Grown,  

E-Print Network (OSTI)

photovoltaic cells,1-5 field-effect transistors,6,7 light-emitting diodes,8 photodetectors,9 and molecular sen

Heaton, Thomas H.

290

Advances in computational mass spectrometry : phosphoprotoemics and proteogenomics  

E-Print Network (OSTI)

and phosphorylation mediated NF-KB activiation. Four histoneto be activated, or relay the signal. In NF-KB signaling, atranscription factor (NF-KB) is held inactive outside the

Payne, Samuel Harris

2008-01-01T23:59:59.000Z

291

Hadamard Transform Time-of-Flight Mass Spectrometry  

E-Print Network (OSTI)

of the ions. This multiplexing scheme in- creases the ion usage to 50% for a single detector instrument consists of a combination of magnetic and electric resolving stages. This is probably the oldest type

Zare, Richard N.

292

2-4 High-Performance Mass Spectrometry Facility  

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

through soil and into groundwater. The mechanism for this reduction in contaminant mobility is the transfer of an electron to the heavy metal through cell surface proteins...

293

Jar mechanism accelerator  

SciTech Connect

This patent describes an accelerator for use with a jar mechanism in a well pipe string to enhance the jarring impact delivered to a stuck object wherein the jar mechanism includes inner and outer members for connection, respectively, between the well pipe string the stuck object. The jar mechanism members are constructed to (1) restrict relative longitudinal movement therebetween to build up energy in the well pipe string and accelerator and then (2) to release the jar mechanism members for unrestrained, free relative longitudinal movement therebetween to engage jarring surfaces on the jar mechanism members for delivering a jarring impact to the stuck object. The accelerator includes: inner and outer telescopically connected members relatively movable longitudinally to accumulate energy in the accelerator; the inner and outer accelerator members each having means for connecting the accelerator in the well pipe string; means associated with the inner and outer members for initially accomodating a predetermined minimum length of unrestrained, free relative longitudinal movement between the inner and outer accelerator members.

Anderson, E.A.; Webb, D.D.

1989-07-11T23:59:59.000Z

294

BNL | Accelerating Particles Accelerates Science - With Big Benefits...  

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

program focused on developing the next crop of bold accelerator scientists and engineers. Photo of CASE participants The Center for Accelerator Science and Education (CASE)...

295

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)

296

Superfund accelerated cleanup model  

SciTech Connect

In an effort to speed and maximize cleanup of the worst sites first, the Environmental Protection Agency (EPA) developed the Superfund Accelerated Cleanup Model (SACM). SACM streamlines the Superfund process so hazardous waste sites can be addressed quicker and in a more cost effective manner. EPA Regional offices developed a number of pilot projects to test the principles of SACM. Although many pilots are underway in the Regions, the pilots described here involve four areas: accelerating cleanup through early actions; integrating site assessments; using Regional Decision Teams to establish priorities; and accelerating cleanup through the use of new technology.

Not Available

1994-08-01T23:59:59.000Z

297

The Fast Lane: Fermilab's Accelerators  

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

Lane: Accelerators at Fermilab Introduction Introduction to Accelerators Accelerator Chain Cockcroft-Walton How it works How it looks Linac How it works How it looks Booster How it...

298

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

299

Accelerated Aging of Roofing Surfaces  

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

Ohio CRRC, Arizona CRRC, Florida CRRC, Ohio 6 | Building Technologies Office eere.energy.gov Approach: develop accelerated aging method Accelerated soiling (atmospheric...

300

Physics Out Loud - Particle Accelerator  

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

Nucleus Previous Video (Nucleus) Physics Out Loud Main Index Next Video (Particle Resonance) Particle Resonance Particle Accelerator Andrew Hutton, Director of Accelerators at...

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.
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to obtain the most current and comprehensive results.


301

Linear Accelerator | Advanced Photon Source  

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

electrons emitted from a cathode heated to 1100 C. The electrons are accelerated by high-voltage alternating electric fields in a linear accelerator (linac; photo below)....

302

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

303

Charged particle accelerator grating  

DOE Patents (OSTI)

A readily disposable and replaceable accelerator grating for a relativistic particle accelerator is described. The grating is formed for a plurality of liquid droplets that are directed in precisely positioned jet streams to periodically dispose rows of droplets along the borders of a predetermined particle beam path. A plurality of lasers are used to direct laser beams onto the droplets, at predetermined angles, thereby to excite the droplets to support electromagnetic accelerating resonances on their surfaces. Those resonances operate to accelerate and focus particles moving along the beam path. As the droplets are distorted or destroyed by the incoming radiation, they are replaced at a predetermined frequency by other droplets supplied through the jet streams.

Palmer, R.B.

1985-09-09T23:59:59.000Z

304

CEBAF accelerator achievements  

Science Conference Proceedings (OSTI)

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

305

Accelerating Turing Machines  

Science Conference Proceedings (OSTI)

Accelerating Turing machines are Turing machines of a sort able to perform tasks that are commonly regarded as impossible for Turing machines. For example, they can determine whether or not the decimal representation of ? contains n consecutive 7s, ... Keywords: ?-machine, Chinese room argument, Church–Turing thesis, accelerating Turing machine, decision problem, effective procedure, halting problem, hypercomputation, hypercomputer, infinity machine, oracle machine, super-task

B. Jack Copeland

2002-05-01T23:59:59.000Z

306

The other high resolution post accelerator approach  

Science Conference Proceedings (OSTI)

There has been significant discussion in consideration of a high resolution mass separator followed by a RFQ and a linear accelerator as the basic format for IsoSpin Laboratory. There exists another strong possibility-namely a low-resolution mass separator coupled to a cyclotron. The major objection to this approach has been that the conversion from the +1 mass separator beam to a q/m beam of 1/4 to 1/3 is thought to be highly inefficient. Since we are in the fortunate position of having the two expensive components of this system available for tests (an on-line mass separator and an ECR source), we intend to couple these devices to actually measure these efficiencies and to test ideas for improving the efficiency. We present some specifics of this approach.

Moltz, D.M.; Tighe, R.J.; Rowe, M.W.; Ognibene, T.J.; Cerny, J.

1993-05-24T23:59:59.000Z

307

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

308

Plasma-based accelerator structures  

SciTech Connect

Plasma-based accelerators have the ability to sustain extremely large accelerating gradients, with possible high-energy physics applications. This dissertation further develops the theory of plasma-based accelerators by addressing three topics: the performance of a hollow plasma channel as an accelerating structure, the generation of ultrashort electron bunches, and the propagation of laser pulses is underdense plasmas.

Schroeder, Carl B.

1999-12-01T23:59:59.000Z

309

Collective Acceleration in Solar Flares  

E-Print Network (OSTI)

Laboratory UNIVERSITY OF CALIFORNIA Accelerator & FusionLaboratory, University of California, Berkeley, CA 94720 (2)

Barletta, W.

2008-01-01T23:59:59.000Z

310

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.

311

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

312

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

313

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

314

High intensity hadron accelerators  

SciTech Connect

This rapporteur report consists mainly of two parts. Part I is an abridged review of the status of all High Intensity Hadron Accelerator projects in the world in semi-tabulated form for quick reference and comparison. Part II is a brief discussion of the salient features of the different technologies involved. The discussion is based mainly on my personal experiences and opinions, tempered, I hope, by the discussions I participated in in the various parallel sessions of the workshop. In addition, appended at the end is my evaluation and expression of the merits of high intensity hadron accelerators as research facilities for nuclear and particle physics.

Teng, L.C.

1989-05-01T23:59:59.000Z

315

An accelerator technology legacy  

Science Conference Proceedings (OSTI)

Accelerator technology has been a major beneficiary of the investment made over the last decade. It is the intention of this paper to provide the reader with a glimpse of the broad nature of those advances. Development has been on a broad front and this paper can highlight only a few of those. Two spin-off applications will be outlined -- a concept for a compact, active, beam probe for solar body exploration and the concept for an accelerator-driven transmutation system for energy production.

Heighway, E.A.

1994-11-01T23:59:59.000Z

316

Negative mass  

E-Print Network (OSTI)

Some physical aspects of negative mass are examined. Several unusual properties, such as the ability of negative mass to penetrate any armor, are analyzed. Other surprising effects include the bizarre system of negative mass chasing positive pass, naked singularities and the violation of cosmic censorship, wormholes, and quantum mechanical results as well. In addition, a brief look into the implications for strings is given.

Richard T Hammond

2013-08-06T23:59:59.000Z

317

A post accelerator for the U.S. rare isotope accelerator facility.  

Science Conference Proceedings (OSTI)

Work supported by the U. S. Department of Energy under contract W-31-109-ENG-38. The proposed Rare Isotope Accelerator (RIA) Facility includes a post-accelerator for rare isotopes (RIB linac) which must produce high-quality beams of radioactive ions over the full mass range, including uranium, at energies above the coulomb barrier, and have high transmission and efficiency. The latter requires the RIB linac to accept at injection ions in the 1+ charge state. A concept for such a post accelerator suitable for ions up to mass 132 has been previously described [1]. This paper presents a modified concept which extends the mass range to uranium. A high resolution separator for purifying beams at the isobaric level precedes the RIB linac. The mass filtering process will provide high purity beams while preserving transmission. For most cases a resolution of about m/{Delta}m=20,000 is adequate at mass A=100 to obtain a separation between isobars of mass excess difference of 5 MeV. The design for a device capable of purifying beams at the isobaric level included calculations up to 5th order. The RIB linac will utilize existing superconducting heavy-ion linac technology for all but a small portion of the accelerator system. The exceptional piece, a very-low-charge-state injector, section needed for just the first few MV of the RIB accelerator, consists of a pre-buncher followed by several sections of cw, normally-conducting RFQ. Two stages of charge stripping are provided: helium gas stripping at energies of a few keV/u, and additional foil stripping at {approx}680 keV/u for the heavier ions. In extending the mass range to uranium, however, for best efficiency the helium gas stripping must be performed at different energies for different mass ions. We present numerical simulations of the beam dynamics of a design for the complete RIB linac which provides for several stripping options and uses cost-effective solenoid focusing elements in the drift-tube linac.

Ostroumov, P. N.; Kelly, M. P.; Kolomiets, A. A.; Nolen, J. A.; Portillo, M.; Shepard, K. W.; Vinogradov, N. E.

2002-06-11T23:59:59.000Z

318

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

319

Portable Linear Accelerator Development  

Science Conference Proceedings (OSTI)

This report describes Minac-3, a miniaturized linear accelerator system. It covers the current equipment capabilities and achievable modifications, applications information for prospective users, and technical information on high-energy radiography that is useful for familiarization and planning. The design basis, development, and applications history of Minac are also summarized.

1982-12-01T23:59:59.000Z

320

Tightly Coupled Accelerators Architecture for Minimizing Communication Latency among Accelerators  

Science Conference Proceedings (OSTI)

In recent years, heterogeneous clusters using accelerators have been widely used in high performance computing systems. In such clusters, inter-node communication among accelerators requires several memory copies via CPU memory, and the communication ... Keywords: GPGPU, Accelerator Computing, Interconnection Network, PCI Express, Remote DMA, CUDA, GPU Direct

Toshihiro Hanawa, Yuetsu Kodama, Taisuke Boku, Mitsuhisa Sato

2013-05-01T23:59:59.000Z

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.


321

Mass Measurements  

Science Conference Proceedings (OSTI)

... NIST maintains the national standard for mass in the form of the prototype kilogram (K20) and provides services to support the parts of the national ...

2013-06-28T23:59:59.000Z

322

fehlende Masse  

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

beim radioaktiven Zerfall mit der fehlenden Masse?" Zur Erinnerung: wenn Uran in Thorium und ein alpha Teilchen zerfllt, dann gehen 0.0046 u (Masseneinheiten) der...

323

Accelerations in Steep Gravity Waves  

Science Conference Proceedings (OSTI)

Surface accelerations can be measured in at least two ways: 1) by a fixed vertical wave guage, 2) by a free-floating buoy. This gives rise to two different vertical accelerations, called respectively “apparent” and “real”, or Langrangian. This ...

M. S. Longuet-Higgins

1985-11-01T23:59:59.000Z

324

BNL | Accelerators for Scientific Research  

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

the development of the next crop of accelerator scientists and engineers, promises to train even more. With its history of building world-class accelerators and its proximity to...

325

SSRL Accelerator Phycics Home Page  

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

(29047 bytes) ICFA2000t.gif (31362 bytes) Home Page LCLS Accelerator Physics at SSRL The field tha t can be covered by the Accelerator Physics activities at SSRL is limited...

326

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

327

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,

328

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

329

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

330

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

331

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

332

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.

333

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,

334

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

335

Research | SLAC National Accelerator Laboratory  

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

Accelerators and Society Astrophysics & Cosmology Biology Elementary Particle Physics Environmental Science Materials, Chemistry & Energy Sciences Scientific Computing X-ray...

336

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

337

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

338

ION ACCELERATION SYSTEM  

DOE Patents (OSTI)

Well focused, intense ion beams are obtained by providing a multi- apertured source grid in front of an ion source chamber and an accelerating multi- apertured grid closely spaced from and in alignment with the source grid. The longest dimensions of the elongated apertures in the grids are normal to the direction of the magnetic field used with the device. Large ion currents may be withdrawn from the source, since they do not pass through any small focal region between the grids.

Luce, J.S.; Martin, J.A.

1960-02-23T23:59:59.000Z

339

ACCELERATION INTEGRATING MEANS  

DOE Patents (OSTI)

An acceleration responsive device is described. A housing has at one end normally open electrical contacts and contains a piston system with a first part of non-magnetic material having metering orifices in the side walls for forming an air bearing between it and the walls of the housing; this first piston part is normally held against the other end of the housing from the noted contacts by a second piston or reset part. The reset part is of partly magnetic material, is separable from the flrst piston part, and is positioned within the housing intermediate the contacts and the first piston part. A magnet carried by the housing imposes a retaining force upon the reset part, along with a helical compression spring that is between the reset part and the end with the contacts. When a predetermined acceleration level is attained, the reset part overcomes the bias or retaining force provided by the magnet and the spring'' snaps'' into a depression in the housing adjacent the contacts. The first piston part is then free to move toward the contacts with its movement responsive tc acceleration forces and the metering orifices. (AEC)

Wilkes, D.F.

1961-08-29T23:59:59.000Z

340

TRACKING ACCELERATOR SETTINGS.  

Science Conference Proceedings (OSTI)

Recording setting changes within an accelerator facility provides information that can be used to answer questions about when, why, and how changes were made to some accelerator system. This can be very useful during normal operations, but can also aid with security concerns and in detecting unusual software behavior. The Set History System (SHS) is a new client-server system developed at the Collider-Accelerator Department of Brookhaven National Laboratory to provide these capabilities. The SHS has been operational for over two years and currently stores about IOOK settings per day into a commercial database management system. The SHS system consists of a server written in Java, client tools written in both Java and C++, and a web interface for querying the database of setting changes. The design of the SHS focuses on performance, portability, and a minimal impact on database resources. In this paper, we present an overview of the system design along with benchmark results showing the performance and reliability of the SHS over the last year.

D OTTAVIO,T.; FU, W.; OTTAVIO, D.P.

2007-10-15T23:59:59.000Z

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.


341

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

342

Accelerator Operations and Physics - Advanced Photon Source  

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

Accelerator Operations & Physics Accelerator Systems Division---Argonne National Laboratory Mission Statement Safe, reliable, attentive, and responsive operation of APS accelerator...

343

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

344

Field Asymmetric Ion Mobility Spectrometry (FAIMS ...  

Summary. Field asymmetric Ion mobility spectrometry (FAIMS), wherein ions are separated and/or characterized by differences in their mobility in high ...

345

RAPID COMMUNICATIONS IN MASS SPECTROMETRY Rapid Commun. Mass Spectrom. 2005; 19: 34423450  

E-Print Network (OSTI)

and oxygen isotope ratios of bottled waters of the world Gabriel J. Bowen1 *, David A. Winter2 , Howard J Biology Department, University of Utah, Salt Lake City, UT 84112, USA 2 Department of Geology, University of Calfornia, Davis, CA 95616, USA 3 Geology and Geophysics, University of Utah, Salt Lake City, UT 84112, USA

Ehleringer, Jim

346

Muon Acceleration - RLA and FFAG  

SciTech Connect

Various acceleration schemes for muons are presented. The overall goal of the acceleration systems: large acceptance acceleration to 25 GeV and 'beam shaping' can be accomplished by various fixed field accelerators at different stages. They involve three superconducting linacs: a single pass linear Pre-accelerator followed by a pair of multi-pass Recirculating Linear Accelerators (RLA) and finally a non-scaling FFAG ring. The present baseline acceleration scenario has been optimized to take maximum advantage of appropriate acceleration scheme at a given stage. The solenoid based Pre-accelerator offers very large acceptance and facilitates correction of energy gain across the bunch and significant longitudinal compression trough induced synchrotron motion. However, far off-crest acceleration reduces the effective acceleration gradient and adds complexity through the requirement of individual RF phase control for each cavity. The RLAs offer very efficient usage of high gradient superconducting RF and ability to adjust path-length after each linac pass through individual return arcs with uniformly periodic FODO optics suitable for chromatic compensation of emittance dilution with sextupoles. However, they require spreaders/recombiners switchyards at both linac ends and significant total length of the arcs. The non-scaling Fixed Field Alternating Gradient (FFAG) ring combines compactness with very large chromatic acceptance (twice the injection energy) and it allows for large number of passes through the RF (at least eight, possibly as high as 15).

Alex Bogacz

2011-10-01T23:59:59.000Z

347

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

348

Thermoelectric battery, protected against shocks and accelerations  

SciTech Connect

In a thermoelectric battery the heat source is suspended on the end of a thermoelectric unit, the other end of which is attached via a heat conducting mass to the casing. A resilient mounting permits resilient rocking of the thermoelectric unit to reduce stress on the unit in the event of shock or acceleration applied to the casing and spring fingers not normally in contact with the heat source or the thermoelectric unit are positioned to arrest the heat source if the assembly rocks more than a predetermined amount.

Brown, M.H.; Myatt, J.

1979-07-24T23:59:59.000Z

349

Accelerating Innovation Webinar Series - Energy Innovation Portal  

Accelerating Innovation Webinar Series. In partnership with the Battelle Commercialization Council, the Energy Innovation Portal is hosting an Accelerating Innovation ...

350

Broadband accelerator control network  

SciTech Connect

A broadband data communications network has been implemented at BNL for control of the Alternating Gradient Synchrotron (AG) proton accelerator, using commercial CATV hardware, dual coaxial cables as the communications medium, and spanning 2.0 km. A 4 MHz bandwidth Digital Control channel using CSMA-CA protocol is provided for digital data transmission, with 8 access nodes available over the length of the RELWAY. Each node consists of an rf modem and a microprocessor-based store-and-forward message handler which interfaces the RELWAY to a branch line implemented in GPIB. A gateway to the RELWAY control channel for the (preexisting) AGS Computerized Accelerator Operating system has been constructed using an LSI-11/23 microprocessor as a device in a GPIB branch line. A multilayer communications protocol has been defined for the Digital Control Channel, based on the ISO Open Systems Interconnect layered model, and a RELWAY Device Language defined as the required universal language for device control on this channel.

Skelly, J.; Clifford, T.; Frankel, R.

1983-01-01T23:59:59.000Z

351

Magnetic Insulation for Electrostatic Accelerators  

Science Conference Proceedings (OSTI)

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

352

Coronal Heating versus Solar Wind Acceleration  

E-Print Network (OSTI)

Parker's initial insights from 1958 provided a key causal link between the heating of the solar corona and the acceleration of the solar wind. However, we still do not know what fraction of the solar wind's mass, momentum, and energy flux is driven by Parker-type gas pressure gradients, and what fraction is driven by, e.g., wave-particle interactions or turbulence. SOHO has been pivotal in bringing these ideas back to the forefront of coronal and solar wind research. This paper reviews our current understanding of coronal heating in the context of the acceleration of the fast and slow solar wind. For the fast solar wind, a recent model of Alfven wave generation, propagation, and non-WKB reflection is presented and compared with UVCS, SUMER, radio, and in-situ observations at the last solar minimum. The derived fractions of energy and momentum addition from thermal and nonthermal processes are found to be consistent with various sets of observational data. For the more chaotic slow solar wind, the relative roles of steady streamer-edge flows (as emphasized by UVCS abundance analysis) versus bright blob structures (seen by LASCO) need to be understood before the relation between streamer heating and and slow-wind acceleration can be known with certainty. Finally, this presentation summarizes the need for next-generation remote-sensing observations that can supply the tight constraints needed to unambiguously characterize the dominant physics.

Steven R. Cranmer

2004-09-29T23:59:59.000Z

353

Pulsed electromagnetic acceleration of exploded wire plasmas  

Science Conference Proceedings (OSTI)

A simple analysis of the dynamic state of a current-conducting high-density plasma column, resulting from an exploded wire between the conductors of a rail-gun accelerator or one or more wires strung between the anode and cathode conductors in a pulsed-power generator diode, is given on the basis of a one-dimensional magnetohydrodynamics model. Spatial distributions of the current density, magnetic field, temperature, and particle density are calculated as well as the temporal current, voltage, and impedance histories. The model self-consistently treats the accelerator load transition through its solid, melt, vapor, and plasma states in the presence of its supply source and feed network. Once formed and accelerated, the plasma state calculations show expansion cooling across the self-induced magnetic field if the Bennett condition is not satisfied. The model predictions are compared to two experimental situations. The first involves the delivery of some hundreds of Joules of stored energy to the wire load. For this case, good agreement between the calculated and observed plasma state is obtained. The second situation involves the delivery of many thousands of Joules to the wire load. For this case and dependent upon the wire mass, diameter, number of wires exploded, their separation, and the pulsed energy electrical wave shapes, the magnetohydrodynamic results can be qualitatively incorrect. The necessity of an electromagnetic particle simulation approach is indicated in order to resolve the magnetic rope-like structure and filamentation observed in the very energetic plasmas.

Peratt, A.L.; Koert, P.

1983-11-01T23:59:59.000Z

354

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

355

Challenges in Accelerator Beam Instrumentation  

E-Print Network (OSTI)

The challenges in beam instrumentation and diagnostics for present and future particle accelerator projects are presented. A few examples for advanced hadron and lepton beam diagnostics are given.

Wendt, M

2009-01-01T23:59:59.000Z

356

Challenges in Accelerator Beam Instrumentation  

Science Conference Proceedings (OSTI)

The challenges in beam instrumentation and diagnostics for present and future particle accelerator projects are presented. A few examples for advanced hadron and lepton beam diagnostics are given.

Wendt, M.

2009-12-01T23:59:59.000Z

357

Ultrafast Accelerators for Pulse Radiolysis  

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

in this area agreed that it would be useful to organize a specialist's conference on ultrafast accelerators for pulse radiolysis, to discuss the common experiences and problems...

358

BNL | Accelerators for Scientific Research  

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

for Basic Research Brookhaven National Lab excels at the design, construction, and operation of large-scale accelerator facilities, a tradition that started with the Cosmotron and...

359

Science at SLAC National Accelerator  

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

matter and dark energy, and develop smaller, more efficient versions of particle accelerators widely used in research, medicine and industry. As our second half-century unfolds,...

360

Argonne's Accelerator Science and Technology  

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

has significant expertise in modeling, design, and operation of both electron accelerators and free electron lasers; undulator design, fabrication, and measurement; control...

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

XML-based Test Accelerator  

Science Conference Proceedings (OSTI)

... A test accelerator that provides core reusable components, yet allows input and output formats to be defined by the user, will facilitate building ...

2011-12-02T23:59:59.000Z

362

SLAC National Accelerator Laboratory - Organization  

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

Organization PHOTO: Aerial view of SLAC Campus SLAC National Accelerator Laboratory is operated by Stanford University for the U.S. Department of Energy's Office of Science. The...

363

Science Accelerator : User Login  

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

Login Login The Science Accelerator ALERTS feature will automatically update you regarding newly available information in your specific area(s) of interest. Simply register for the service, then create a search strategy which will be run against information added to . Select a schedule (weekly, monthly, etc.) for receiving the email Alerts. If you are a new patron, Register to learn how to set up Alerts to meet your needs. If you are an existing patron, enter your user name and password in the boxes to login. Once logged in, you may review or modify your search, add a new search and see recent Alerts results. User Name: Password: Remember Me Remember me on this computer. Login Don't have a user name? Register! Forgot your password? Reset your password Alerts The Alerts function allows you to monitor a topic and receive timely

364

Science Accelerator : Your Selections  

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

Your Selections Back To Previous Page Selections - of First Page Previous Page Next Page Last Page Back To Previous Page You have 0 selections. Click the checkboxes clipping.addClipping on the results or alert results pages to add to your selections. Some links on this page may take you to non-federal websites. Their policies may differ from this site. U.S. Department of Energy U.S. Department of Energy Office of Science Office of Scientific and Technical Information Website Policies/Important Links Science Accelerator science.gov WorldWideScience.org Deep Web Technologies Email Results Use this form to email your search results * Email this to: * Your Name: Comments: URL only?: Number of results: 10 20 50 100 200 All Email Format: HTML TEXT * Required field Print Results

365

HIGH ENERGY PARTICLE ACCELERATOR  

DOE Patents (OSTI)

An improved apparatus is presented for focusing charged particles in an accelerator. In essence, the invention includes means for establishing a magnetic field in discrete sectors along the path of moving charged particles, the magnetic field varying in each sector in accordance with the relation. B = B/ sub 0/ STAln (r-r/sub 0/)/r/sub 0/!, where B/sub 0/ is the value of the magnetic field at the equilibrium orbit of radius r/sub 0/ of the path of the particles, B equals the magnetic field at the radius r of the chamber and n equals the magnetic field gradient index, the polarity of n being abruptly reversed a plurality of times as the particles travel along their arcuate path. With this arrangement, the particles are alternately converged towards the axis of their equillbrium orbit and diverged therefrom in successive sectors with a resultant focusing effect.

Courant, E.D.; Livingston, M.S.; Snyder, H.S.

1959-04-14T23:59:59.000Z

366

Accelerations in Steep Gravity Waves. II: Subsurface Accelerations  

Science Conference Proceedings (OSTI)

It is shown that the vertical acceleration of a particle beneath the crest of a step gravity wave does not always decrease monotonically with depth in the fluid. When the wave steepness ak exceeds 0.4, the acceleration at first increases with ...

M. S. Longuet-Higgins

1986-07-01T23:59:59.000Z

367

SPEAR3 Accelerator Physics Update  

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

SPEAR3 ACCELERATOR PHYSICS UPDATE* SPEAR3 ACCELERATOR PHYSICS UPDATE* J. Safranek # , W.J. Corbett, R. Hettel, X. Huang, Y. Nosochkov, J. Sebek, A. Terebilo, SSRL/SLAC, Menlo Park, CA, U.S.A. Abstract The SPEAR3 [1,2] storage ring at Stanford Synchrotron Radiation Laboratory has been delivering photon beams for three years. We will give an overview of recent and ongoing accelerator physics activities, including 500 mA fills, work toward top-off injection, long-term orbit stability characterization and improvement, fast orbit feedback, new chicane optics, low alpha optics & short bunches, low emittance optics, and MATLAB software. The accelerator physics group has a strong program to characterize and improve SPEAR3 performance. INTRODUCTION In this summary of the past three years of accelerator

368

Nuclear Materials Identification System (NMIS) with Gamma Spectrometry for Attributes of Pu, HEU, and Detection of HE and Chemical Agents  

SciTech Connect

A combined Nuclear Materials Identification System (NMIS)-gamma ray spectrometry system can be used passively to obtain the following attributes of Pu: presence, fissile mass, 240/239 ratio, and metal vs. oxide. This system can also be used with a small, portable, DT neutron generator to measure the attributes of highly enriched uranium (HEU): presence, fissile mass, enrichment, metal vs. oxide; and detect the presence of high explosives (HE). For the passive system, time-dependent coincidence distributions can be used for the presence, fissile mass, metal vs. oxide for Pu, and gamma-ray spectrometry can be used for 239/240 ratio and presence. So presence can be confirmed by two methods. For the active system with a DT neutron generator, all four attributes for both Pu and HEU can be determined from various features of the time-dependent coincidence distribution measurements for both Pu and HEU. Active gamma ray spectrometry would also give presence and 240/239 ratio for Pu, enrichment for HEU, and metal vs. oxide for both. Active gamma ray spectrometry would determine the presence of HE. The various features of time-dependent coincidence distributions and gamma ray spectrometry that determine these attributes are discussed with some examples from previous determinations.

Mihalczo, J. T.; Mattingly, J. K.; Mullens, J. A.; Neal, J. S.

2002-05-01T23:59:59.000Z

369

Thomas Jefferson National Accelerator Facility Site Tour - Accelerator Map  

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

Counting House Free Electron Accelerator Facility Machine Control Center Physics Storage Building North Linear Accelerator South Linear Accelerator VEPCO Substation Machine Control Center Annex Machine Control Center Annex II North Access Building South Access Building Central Helium Liquefier Injector Hall A Truck Ramp Hall B Truck Ramp Hall C Truck Ramp Experimental Hall A Experimental Hall B Experimental Hall C East Arc West Arc Counting House Free Electron Accelerator Facility Machine Control Center Physics Storage Building North Linear Accelerator South Linear Accelerator VEPCO Substation Machine Control Center Annex Machine Control Center Annex II North Access Building South Access Building Central Helium Liquefier Injector Hall A Truck Ramp Hall B Truck Ramp Hall C Truck Ramp Experimental Hall A Experimental Hall B Experimental Hall C East Arc West Arc Science Education Jefferson Lab Jefferson Lab Home Search Jefferson Lab Contact Jefferson Lab Science Education Home Teacher Resources Student Zone Games and Puzzles Science Cinema Programs and Events Search Education Privacy and Security Notice Jefferson Lab Site Tour Guided Tour Site Map Accelerator Area Map Administrative Area Map Tour Index

370

EXOTIC MAGNETS FOR ACCELERATORS.  

SciTech Connect

Over the last few years, several novel magnet designs have been introduced to meet the requirements of new, high performance accelerators and beam lines. For example, the FAIR project at GSI requires superconducting magnets ramped at high rates ({approx} 4 T/s) in order to achieve the design intensity. Magnets for the RIA and FAIR projects and for the next generation of LHC interaction regions will need to withstand high doses of radiation. Helical magnets are required to maintain and control the polarization of high energy protons at RHIC. In other cases, novel magnets have been designed in response to limited budgets and space. For example, it is planned to use combined function superconducting magnets for the 50 GeV proton transport line at J-PARC to satisfy both budget and performance requirements. Novel coil winding methods have been developed for short, large aperture magnets such as those used in the insertion region upgrade at BEPC. This paper will highlight the novel features of these exotic magnets.

WANDERER, P.

2005-09-18T23:59:59.000Z

371

RFQ accelerator tuning system  

DOE Patents (OSTI)

A cooling system is provided for maintaining a preselected operating temperature in a device, which may be an RFQ accelerator, having a variable heat removal requirement, by circulating a cooling fluid through a cooling system remote from the device. Internal sensors in the device enable an estimated error signal to be generated from parameters which are indicative of the heat removal requirement from the device. Sensors are provided at predetermined locations in the cooling system for outputting operational temperature signals. Analog and digital computers define a control signal functionally related to the temperature signals and the estimated error signal, where the control signal is defined effective to return the device to the preselected operating temperature in a stable manner. The cooling system includes a first heat sink responsive to a first portion of the control signal to remove heat from a major portion of the circulating fluid. A second heat sink is responsive to a second portion of the control signal to remove heat from a minor portion of the circulating fluid. The cooled major and minor portions of the circulating fluid are mixed in response to a mixing portion of the control signal, which is effective to proportion the major and minor portions of the circulating fluid to establish a mixed fluid temperature which is effective to define the preselected operating temperature for the remote device. In an RFQ environment the stable temperature control enables the resonant frequency of the device to be maintained at substantially a predetermined value during transient operations.

Bolie, Victor W. (Albuquerque, NM)

1990-01-01T23:59:59.000Z

372

Mass Finishing  

Science Conference Proceedings (OSTI)

Table 8 Operating conditions for mass finishing...Brass screw-machine parts Aluminum oxide or granite 6.4-19 0.25-0.75 [MathExpression] -6 Light matte or bright Light cutting (a) Brass stampings or screws (b) Limestone 3.2-13 0.13-0.50 2-6 Bright (a) Submerged tumbling is used for fragile and precision parts. (b) Screw-machine parts...

373

Uniformly accelerating black holes in a de Sitter universe  

E-Print Network (OSTI)

A class of exact solutions of Einstein's equations is analysed which describes uniformly accelerating charged black holes in an asymptotically de Sitter universe. This is a generalisation of the C-metric which includes a cosmological constant. The physical interpretation of the solutions is facilitated by the introduction of a new coordinate system for de Sitter space which is adapted to accelerating observers in this background. The solutions considered reduce to this form of the de Sitter metric when the mass and charge of the black holes vanish.

J. Podolsky; J. B. Griffiths

2000-10-30T23:59:59.000Z

374

Electron beam accelerator with magnetic pulse compression and accelerator switching  

DOE Patents (OSTI)

An electron beam accelerator comprising an electron beam generator-injector to produce a focused beam of .gtoreq.0.1 MeV energy electrons; a plurality of substantially identical, aligned accelerator modules to sequentially receive and increase the kinetic energies of the beam electrons by about 0.1-1 MeV per module. Each accelerator module includes a pulse-forming network that delivers a voltage pulse to the module of substantially 0.1-1 MeV maximum energy over a time duration of .ltoreq.1 .mu.sec.

Birx, Daniel L. (Brentwood, CA); Reginato, Louis L. (Orinda, CA)

1987-01-01T23:59:59.000Z

375

Electron beam accelerator with magnetic pulse compression and accelerator switching  

DOE Patents (OSTI)

An electron beam accelerator comprising an electron beam generator-injector to produce a focused beam of .gtoreq.0.1 MeV energy electrons; a plurality of substantially identical, aligned accelerator modules to sequentially receive and increase the kinetic energies of the beam electrons by about 0.1-1 MeV per module. Each accelerator module includes a pulse-forming network that delivers a voltage pulse to the module of substantially .gtoreq.0.1-1 MeV maximum energy over a time duration of .ltoreq.1 .mu.sec.

Birx, Daniel L. (Brentwood, CA); Reginato, Louis L. (Orinda, CA)

1988-01-01T23:59:59.000Z

376

Electron beam accelerator with magnetic pulse compression and accelerator switching  

DOE Patents (OSTI)

An electron beam accelerator is described comprising an electron beam generator-injector to produce a focused beam of greater than or equal to .1 MeV energy electrons; a plurality of substantially identical, aligned accelerator modules to sequentially receive and increase the kinetic energies of the beam electron by about .1-1 MeV per module. Each accelerator module includes a pulse-forming network that delivers a voltage pulse to the module of substantially .1-1 MeV maximum energy over a time duration of less than or equal to 1 ..mu..sec.

Birx, D.L.; Reginato, L.L.

1984-03-22T23:59:59.000Z

377

Chemical ionization tandem mass spectrometer for the in situ measurement of methyl hydrogen peroxide  

SciTech Connect

A new approach for measuring gas-phase methyl hydrogen peroxide [(MHP) CH{sub 3}OOH] utilizing chemical ionization mass spectrometry is presented. Tandem mass spectrometry is used to avoid mass interferences that hindered previous attempts to measure atmospheric CH{sub 3}OOH with CF{sub 3}O{sup -} clustering chemistry. CH{sub 3}OOH has been successfully measured in situ using this technique during both airborne and ground-based campaigns. The accuracy and precision for the MHP measurement are a function of water vapor mixing ratio. Typical precision at 500 pptv MHP and 100 ppmv H{sub 2}O is {+-}80 pptv (2 sigma) for a 1 s integration period. The accuracy at 100 ppmv H{sub 2}O is estimated to be better than {+-}40%. Chemical ionization tandem mass spectrometry shows considerable promise for the determination of in situ atmospheric trace gas mixing ratios where isobaric compounds or mass interferences impede accurate measurements.

St Clair, Jason M.; McCabe, David C. [Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, California 91125 (United States); Crounse, John D. [Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125 (United States); Steiner, Urs [Varian, Inc., Santa Clara, California 95051 (United States); Wennberg, Paul O. [Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, California 91125 (United States); Division of Engineering and Applied Science, California Institute of Technology, Pasadena, California 91125 (United States)

2010-09-15T23:59:59.000Z

378

Theoretical Investigations of Plasma-Based Accelerators and Other Advanced Accelerator Concepts  

SciTech Connect

Theoretical investigations of plasma-based accelerators and other advanced accelerator concepts. The focus of the work was on the development of plasma based and structure based accelerating concepts, including laser-plasma, plasma channel, and microwave driven plasma accelerators.

Shuets, G.

2004-05-21T23:59:59.000Z

379

Compact hydrogen/helium isotope mass spectrometer  

DOE Patents (OSTI)

The compact hydrogen and helium isotope mass spectrometer of the present invention combines low mass-resolution ion mass spectrometry and beam-foil interaction technology to unambiguously detect and quantify deuterium (D), tritium (T), hydrogen molecule (H.sub.2, HD, D.sub.2, HT, DT, and T.sub.2), .sup.3 He, and .sup.4 He concentrations and concentration variations. The spectrometer provides real-time, high sensitivity, and high accuracy measurements. Currently, no fieldable D or molecular speciation detectors exist. Furthermore, the present spectrometer has a significant advantage over traditional T detectors: no confusion of the measurements by other beta-emitters, and complete separation of atomic and molecular species of equivalent atomic mass (e.g., HD and .sup.3 He).

Funsten, Herbert O. (Los Alamos, NM); McComas, David J. (Los Alamos, NM); Scime, Earl E. (Morgantown, WV)

1996-01-01T23:59:59.000Z

380

Pulse - Accelerator Science in Medicine  

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

t he future of accelerator physics isn’t just for physicists. As in the past, tomorrow’s discoveries in particle accelerator science may lead to unexpected applications for medical diagnosis, healing and the understanding of human biology. t he future of accelerator physics isn’t just for physicists. As in the past, tomorrow’s discoveries in particle accelerator science may lead to unexpected applications for medical diagnosis, healing and the understanding of human biology. Breakthroughs in the technology of superconducting magnets, nanometer beams, laser instrumentation and information technology will give high-energy physicists new accelerators to explore the deepest secrets of the universe: the ultimate structure of matter and the nature of space and time. But breakthroughs in accelerator science may do more than advance the exploration of particles and forces. No field of science is an island. Physics, astronomy, chemistry, biology, medicine— all interact in the continuing human endeavor to explore and understand our world and ourselves. Research at high-energy physics laboratories will lead to the next generation of particle accelerators—and perhaps to new tools for medical science.

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

Accelerated cleanup risk reduction  

Science Conference Proceedings (OSTI)

There is no proven technology for remediating contaminant plume source regions in a heterogeneous subsurface. This project is an interdisciplinary effort to develop the requisite new technologies so that will be rapidly accepted by the remediation community. Our technology focus is hydrous pyrolysis/oxidation (HPO) which is a novel in situ thermal technique. We have expanded this core technology to leverage the action of steam injection and place an in situ microbial filter downstream to intercept and destroy the accelerated movement of contaminated groundwater. Most contaminant plume source regions, including the chlorinated solvent plume at LLNL, are in subsurface media characterized by a wide range in hydraulic conductivity. At LLNL, the main conduits for contaminant transport are buried stream channels composed of gravels and sands; these have a hydraulic conductivity in the range of 10{sup -1} to 10{sup -2} cm/s. Clay and silt units with a hydraulic conductivity of 10{sup -1} to 10{sup -6} cm/s bound these buried channels; these are barriers to groundwater movement and contain the highest contaminant concentrations in the source region. New remediation technologies are required because the current ones preferentially access the high conductivity units. HPO is an innovative process for the in situ destruction of contaminants in the entire subsurface. It operates by the injection of steam. We have demonstrated in laboratory experiments that many contaminants rapidly oxidize to harmless compounds at temperatures easily achieved by injecting steam, provided sufficient dissolved oxygen is present. One important challenge in a heterogeneous source region is getting heat, contaminants, and an oxidizing agent in the same place at the same time. We have used the NUFT computer program to simulate the cyclic injection of steam into a contaminated aquifer for design of a field demonstration. We used an 8 hour, steam/oxygen injection cycle followed by a 56 hour relaxation period in which the well was `capped`. Our results show the formation of an inclined gas phase during injection and a fast collapse of the steam zone within an hour of terminating steam injection. The majority of destruction occurs during the collapse phase, when contaminant laden water is drawn back towards the well. Little to no noncondensible gasses are created in this process, removing any possibility of sparging processes interfering with contaminant destruction. Our models suggest that the thermal region should be as hot and as large as possible. To have HPO accepted, we need to demonstrate the in situ destruction of contaminants. This requires the ability to inexpensively sample at depth and under high temperatures. We proved the ability to implies monitoring points at depths exceeding 150 feet in highly heterogeneous soils by use of cone penetrometry. In addition, an extractive system has been developed for sampling fluids and measuring their chemistry under the range of extreme conditions expected. We conducted a collaborative field test of HPO at a Superfund site in southern California where the contaminant is mainly creosote and pentachlorophenol. Field results confirm the destruction of contaminants by HPO, validate our field design from simulations, demonstrate that accurate field measurements of the critical fluid parameters can be obtained using existing monitoring wells (and minimal capital cost) and yield reliable cost estimates for future commercial application. We also tested the in situ microbial filter technology as a means to intercept and destroy the accelerated flow of contaminants caused by the injection of steam. A series of laboratory and field tests revealed that the selected bacterial species effectively degrades trichloroethene in LLNL Groundwater and under LLNL site conditions. In addition, it was demonstrated that the bacteria effectively attach to the LLNL subsurface media. An in-well treatability study indicated that the bacteria initially degrade greater than 99% of the contaminant, to concentrations less than regulatory limit

Knapp, R.B.; Aines, R.M.; Blake, R.G.; Copeland, A.B.; Newmark, R.L.; Tompson, A.F.B.

1998-02-01T23:59:59.000Z

382

CORONAL MASS EJECTION MASS, ENERGY, AND FORCE ESTIMATES USING STEREO  

Science Conference Proceedings (OSTI)

Understanding coronal mass ejection (CME) energetics and dynamics has been a long-standing problem, and although previous observational estimates have been made, such studies have been hindered by large uncertainties in CME mass. Here, the two vantage points of the Solar Terrestrial Relations Observatory (STEREO) COR1 and COR2 coronagraphs were used to accurately estimate the mass of the 2008 December 12 CME. Acceleration estimates derived from the position of the CME front in three dimensions were combined with the mass estimates to calculate the magnitude of the kinetic energy and driving force at different stages of the CME evolution. The CME asymptotically approaches a mass of 3.4 {+-} 1.0 Multiplication-Sign 10{sup 15} g beyond {approx}10 R{sub Sun }. The kinetic energy shows an initial rise toward 6.3 {+-} 3.7 Multiplication-Sign 10{sup 29} erg at {approx}3 R{sub Sun }, beyond which it rises steadily to 4.2 {+-} 2.5 Multiplication-Sign 10{sup 30} erg at {approx}18 R{sub Sun }. The dynamics are described by an early phase of strong acceleration, dominated by a force of peak magnitude of 3.4 {+-} 2.2 Multiplication-Sign 10{sup 14} N at {approx}3 R{sub Sun }, after which a force of 3.8 {+-} 5.4 Multiplication-Sign 10{sup 13} N takes effect between {approx}7 and 18 R{sub Sun }. These results are consistent with magnetic (Lorentz) forces acting at heliocentric distances of {approx}Sun }, while solar wind drag forces dominate at larger distances ({approx}>7 R{sub Sun }).

Carley, Eoin P.; Gallagher, Peter T. [Astrophysics Research Group, School of Physics, Trinity College Dublin, Dublin 2 (Ireland); McAteer, R. T. James [Department of Astronomy, New Mexico State University, Las Cruces, NM 88003-8001 (United States)

2012-06-10T23:59:59.000Z

383

SNEAP 80: symposium of Northeastern Accelerator personnel  

SciTech Connect

Reports of operations are presented for twenty-seven facilities, along with reports on accelerators in progress, ion sources, insulating gases, charging systems, stripping foils, accelerating tubes, and upgraded accelerator systems. (GHT)

Billen, J.H. (ed.) ed.

1980-01-01T23:59:59.000Z

384

Laser Wakefield Particle Accelerators Project at NERSC  

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

Particle Acceleration Laser Wakefield Particle Acceleration Vorpal.jpg Key Challenges: Design of multiple-staged, 10-GeV laser-wakefield plasma accelerated next-generation hardware...

385

On the Aerosol Particle Size Distribution Spectrum in Alaskan Air Mass Systems: Arctic Haze and Non-Haze Episodes  

Science Conference Proceedings (OSTI)

Aerosols in central Alaskan winter air mass system were classified according to size by diffusive separation and light-scattering spectrometry. Particles entering central Alaska from the Pacific Marine environment had number concentrations ...

Glenn E. Shaw

1983-05-01T23:59:59.000Z

386

Fermi National Accelerator Laboratory April 2012  

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

into applications for the nation's health, wealth and security. Science at Fermilab Illinois Accelerator Research Center The Illinois Accelerator Research Center, or IARC, will...

387

Science Accelerator content now includes multimedia  

Office of Scientific and Technical Information (OSTI)

Science Accelerator content now includes multimedia Science Accelerator has expanded its suite of collections to include ScienceCinema, which contains videos produced by the U.S....

388

Honda Insight Fleet and Accelerated Reliability Testing  

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

Ford Fusion Hybrid Electric Vehicle Accelerated Testing - May 2012 Two model year 2010 Ford Fusion hybrid electric vehicles (HEVs) entered Accelerated testing during August 2009 in...

389

Honda Insight Fleet and Accelerated Reliability Testing  

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

Mazda 3 Micro Hybrid Vehicle Accelerated Testing - December 2012 Two Mazda 3 European Micro Hybrid Vehicles (MHVs) entered accelerated testing during November 2010 in a fleet in...

390

Honda Insight Fleet and Accelerated Reliability Testing  

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

Volkswagen Golf Micro Hybrid Vehicle Accelerated Testing - December 2012 Two Volkswagen Golf European Micro Hybrid Vehicle (MHVs) entered accelerated testing during October 2010 in...

391

Honda Insight Fleet and Accelerated Reliability Testing  

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

Hybrid Electric Vehicle Accelerated Testing (Model Year 2004) - October 2007 Two (Model Year 2004) Toyota Prius hybrid electric vehicles (HEVs) entered accelerated testing in a...

392

Honda Insight Fleet and Accelerated Reliability Testing  

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

Smart fortwo Micro Hybrid Vehicle Accelerated Testing - December 2012 Three Smart fortwo European Micro Hybrid Vehicles (MHVs) entered accelerated testing during October 2010 in a...

393

Technology Commercialization and Partnerships | CASE Accelerates ...  

The Center for Accelerator Science and ... get hands-on experience using the accelerator and reporting their results. ... R&D funding is especially important for ...

394

Honda Insight Fleet and Accelerated Reliability Testing  

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

Gen III Prius HEV Accelerated Testing - May 2012 Two model year 2010 Toyota Generation III Prius hybrid electric vehicles (HEVs) entered Accelerated testing during July 2009 in a...

395

Argonne Wakefield Accelerator Facility (AWA) Upgrades  

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

Facility is dedicated to the study of advanced accelerator concepts based on electron beam driven wakefield acceleration and RF power generation. The facility employs an...

396

Honda Insight Fleet and Accelerated Reliability Testing  

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

Gen II Insight HEV Accelerated Testing - August 2012 Two model year 2010 Honda Generation II Insight hybrid electric vehicles (HEVs) entered Accelerated testing during July 2009 in...

397

SLAC National Accelerator Laboratory - SLAC's Newest Facility...  

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

the Max Planck Institute of Physics in Berlin will continue their efforts to make accelerators smaller and more efficient using a technique called plasma wakefield acceleration....

398

A Tunable Dielectric Wakefield Accelerating Structure  

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

a (11-13) GHz dielectric accelerating structure. INTRODUCTION The field of advanced accelerators is in search of novel revolutionary technologies to allow progress in particle...

399

SLAC National Accelerator Laboratory - Scientific Programs  

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

Programs Advanced Accelerator Research Particle accelerators are complicated machines, with hundreds of thousands of components that all need to be designed, engineered and...

400

Annual Planning Summaries: Stanford Linear Accelerator (SLAC...  

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

Stanford Linear Accelerator (SLAC) Annual Planning Summaries: Stanford Linear Accelerator (SLAC) Document(s) Available For Download January 11, 2012 2012 Annual Planning Summary...

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

Argonne National Laboratory's Accelerator Experimental Infrastructure  

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

Accelerator Experimental Infrastructure Argonne National Laboratory is somewhat unique among the Office of Science National Laboratories in that it possesses active accelerator...

402

Terahertz radiation from laser accelerated electron bunches  

E-Print Network (OSTI)

NUMBER 5 MAY 2004 Terahertz radiation from laser acceleratedand millimeter wave radiation from laser acceleratedNo. 5, May 2004 Terahertz radiation from laser accelerated

2004-01-01T23:59:59.000Z

403

Honda Insight Fleet and Accelerated Reliability Testing  

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

Civic CNG Accelerated Testing - June 2013 Four model year 2013 Honda Civic compressed natural gas (CNGs) entered Accelerated testing during November 2012 in a fleet in Arizona....

404

Honda Insight Fleet and Accelerated Reliability Testing  

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

Volt EREV Accelerated Testing - June 2013 Four model year 2013 Chevrolet Volt extended range electric vehicles (EREVs) entered Accelerated testing during November 2012 in a fleet...

405

Honda Insight Fleet and Accelerated Reliability Testing  

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

Chevrolet Volt EREV Accelerated Testing - June 2013 Two model year 2011 Chevrolet Volt extended range electric vehicles (EREVs) entered Accelerated testing during March 2011 in a...

406

CRAD, Radiological Controls - Idaho Accelerated Retrieval Project...  

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

Radiological Controls - Idaho Accelerated Retrieval Project Phase II CRAD, Radiological Controls - Idaho Accelerated Retrieval Project Phase II February 2006 A section of Appendix...

407

CRAD, Emergency Management - Idaho Accelerated Retrieval Project...  

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

Emergency Management - Idaho Accelerated Retrieval Project Phase II CRAD, Emergency Management - Idaho Accelerated Retrieval Project Phase II February 2006 A section of Appendix C...

408

BNL | Accelerators for Applied Research  

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

Accelerators for Applied Research Accelerators for Applied Research Brookhaven National Lab operates several accelerator facilities dedicated to applied research. These facilities directly address questions and concerns on a tremendous range of fields, including medical imaging, cancer therapy, computation, and space exploration. Leading scientists lend their expertise to these accelerators and offer crucial assistant to collaborating researchers, pushing the limits of science and technology. Interested in gaining access to these facilities for research? See the contact number listed for each facility. RHIC tunnel Brookhaven Linac Isotope Producer The Brookhaven Linac Isoptope Producer (BLIP)-positioned at the forefront of research into radioisotopes used in cancer treatment and diagnosis-produces commercially unavailable radioisotopes for use by the

409

IMPACT-T: Accelerator Physics  

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

IMPACTT General Description IMPACT-T (Integrated Map and Particle Accelerator Tracking-Time) is a parallel, three-dimensional, quasi-static beam dynamics code used to study...

410

Accelerating and rotating black holes  

E-Print Network (OSTI)

An exact solution of Einstein's equations which represents a pair of accelerating and rotating black holes (a generalised form of the spinning C-metric) is presented. The starting point is a form of the Plebanski-Demianski metric which, in addition to the usual parameters, explicitly includes parameters which describe the acceleration and angular velocity of the sources. This is transformed to a form which explicitly contains the known special cases for either rotating or accelerating black holes. Electromagnetic charges and a NUT parameter are included, the relation between the NUT parameter $l$ and the Plebanski-Demianski parameter $n$ is given, and the physical meaning of all parameters is clarified. The possibility of finding an accelerating NUT solution is also discussed.

J. B. Griffiths; J. Podolsky

2005-07-06T23:59:59.000Z

411

Residual Activation of Accelerator Components  

Science Conference Proceedings (OSTI)

Accelerators / Special Issue on the 11th International Conference on Radiation Shielding and the 15th Topical Meeting of the Radiation Protection and Shielding Division (PART 3) / Radiation Measurements and Instrumentation

I. L. Rakhno; N. V. Mokhov; S. I. Striganov

412

APS Accelerator Systems Division Home  

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

Photon Source and pursues research and development profitable to the science of accelerators and future light source technologies. Featured Image Two 352-MHz1-kW CW solid...

413

What is SLAC National Accelerator  

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

SLAC National Accelerator Laboratory? The numbers tell the tale. SLAC began in 1962 with 200 employees. Nearly 1,700 people now work on staff plus 300 postdoctoral researchers and...

414

Electrodynamics acceleration of electrical dipoles  

E-Print Network (OSTI)

This article considers the acceleration of electric dipoles consisting of thin metal plates and dielectric (barium titanate). The dipoles are of a cylindrical shape with a diameter of the cylinder two centimeters and length one centimeter. Capacity of the parallel-plate capacitor is three hundred picofarads and it is charged up to the voltage of two hundred eighty kilovolts. Pre-acceleration of the electric dipoles till velocity one kilometer per second is reached by the gas-dynamic method. The finite acceleration is produced in a spiral waveguide, where the pulse is travelling with voltage amplitude seven hundreds kilovolts and power one hundred twenty-five megawatts. This pulse travels via the spiral waveguide and accelerates the injected electric dipoles in the longitudinal direction till the finite velocity eight and a half kilometers per second over length seven hundred and seventy meters.

Dolya, S N

2013-01-01T23:59:59.000Z

415

Science Accelerator | Data.gov  

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

Dataset Summary Description Science Accelerator is a gateway to science, including DOE R&D results, major R&D accomplishments, and recent research of interest to U.S. Department...

416

Market Acceleration | Department of Energy  

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

Market Acceleration Market Acceleration Market Acceleration Photo of several men on a floating platform that is lowering monitoring tools into the ocean. The Water Power Program works to foster a commercial market for marine and hydrokinetic (MHK) energy devices in order to achieve its goal of the nation obtaining 15% of its electricity needs from all types of water power by 2030. Though marine and hydrokinetic energy is still in its infancy, the program is developing a robust portfolio of projects to accelerate wave, tidal and current project deployments and development of the MHK market in general. These projects include project siting activities, market assessments, environmental impact analyses, and research supporting technology commercialization. Learn more about the Water Power Program's work in the following areas of

417

Bubble Acceleration in the Ablative Rayleigh-Taylor Instability  

Science Conference Proceedings (OSTI)

The highly nonlinear evolution of the single-mode Rayleigh-Taylor instability (RTI) at the ablation front of an accelerated target is investigated in the parameter range typical of inertial confinement fusion implosions. A new phase of the nonlinear bubble evolution is discovered. After the linear growth phase and a short constant-velocity phase, it is found that the bubble is accelerated to velocities well above the classical value. This acceleration is driven by the vorticity accumulation inside the bubble resulting from the mass ablation adn vorticity convection off the ablation front. While the albative growth rates are slower than their classical values in the linear regime, the ablative RTI grows faster than the classical RTI in the nonlinear regime for deuterium and tritium ablators.

Betti, R.; Sanz, J.

2006-11-20T23:59:59.000Z

418

Bubble Acceleration in the Ablative Rayleigh-Taylor Instability  

SciTech Connect

The highly nonlinear evolution of the single-mode Rayleigh-Taylor instability (RTI) at the ablation front of an accelerated target is investigated in the parameter range typical of inertial confinement fusion implosions. A new phase of the nonlinear bubble evolution is discovered. After the linear growth phase and a short constant-velocity phase, it is found that the bubble is accelerated to velocities well above the classical value. This acceleration is driven by the vorticity accumulation inside the bubble resulting from the mass ablation and vorticity convection off the ablation front. While the ablative growth rates are slower than their classical values in the linear regime, the ablative RTI grows faster than the classical RTI in the nonlinear regime for deuterium and tritium ablators.

Betti, R.; Sanz, J. [Fusion Science Center for Extreme States of Matter and Fast Ignition Physics, Laboratory for Laser Energetics, University of Rochester, 250 East River Road, Rochester, New York 14623 (United States)

2006-11-17T23:59:59.000Z

419

Comparison of accelerator technologies for use in ADSS  

SciTech Connect

Accelerator Driven Subcritical (ADS) fission is an interesting candidate basis for nuclear waste transmutation and for nuclear power generation. ADS can use either thorium or depleted uranium as fuel, operate below criticality, and consume rather than produce long-lived actinides. A case study with a hypothetical, but realistic nuclear core configuration is used to evaluate the performance requirements of the driver proton accelerator in terms of beam energy, beam current, duty factor, beam distribution delivered to the fission core, reliability, and capital and operating cost. Comparison between a CW IC and that of a SRF proton linac is evaluated. Future accelerator R&D required to improve each candidate accelerator design is discussed. ADS fission has interesting potential for electric power generation and also for destruction of long-lived actinide waste produced by conventional critical reactors. ADS systems offer several interesting advantages in comparison to critical reactors: (1) ADS provides greater flexibility for the composition and placement of fissile, fertile, or fission product waste within the core, and require less enrichment of fissile content; (2) The core can be operated with a reactivity k{sub eff} that cannot reach criticality by any failure mode; (3) When the beam is shut off fission ceases in the core; (4) Coupling the fast neutron spectrum of the spallation drive to fast core neutronics offers a basis for more complete burning of long-lived actinides; and (5) ADS designs can provide sufficient thermal mass that meltdown cannot occur from radioactive heat after fission is stopped. In order to drive a {approx}GW{sub e} fission core a CW proton beam of >700 MeV and {approx}15 MW beam power is required. A previous study of the accelerator performance required for ADS systems concluded that present accelerator performance is approaching those requirements, but accelerator system cost and reliability remain particular concerns. The obvious candidates for accelerators that can provide intense CW proton beams are isochronous cyclotrons (IC) and superconducting linacs. We have examined a case study using a hypothetical ADS core configuration to guide our thinking in evaluating those two accelerator technologies for use in ADS systems. Issues of accelerator power, multiplicity of accelerators, and options for core neutronics and fuel form are discussed.

Weng, W.T.; Ludewig, H.; Raparia, D.; Trbojevic, D.; Todosow, M.; McIntyre, P.; Sattarov, A.

2011-03-28T23:59:59.000Z

420

Chemical Ionization Mass Spectrometer (CIMS) Shanhu Lee, Kent State University (http://www.personal.kent.edu/~slee19/)  

E-Print Network (OSTI)

Chemical Ionization Mass Spectrometer (CIMS) Shanhu Lee, Kent State University (http ionization mass spectrometry (PTR-CIMS). A typical CIMS instrument can be constructed from an ion source, an ion molecular reactor, and a quadrupole mass spectrometer. Shown below is schematic diagram of a CIMS

Lee, Shan-Hu

Note: This page contains sample records for the topic "accelerator mass spectrometry" from the National Library of EnergyBeta (NLEBeta).
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We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

High-Intensity Proton Accelerator  

SciTech Connect

Analysis is presented for an eight-cavity proton cyclotron accelerator that could have advantages as compared with other accelerators because of its potentially high acceleration gradient. The high gradient is possible since protons orbit in a sequence of TE111 rotating mode cavities of equally diminishing frequencies with path lengths during acceleration that greatly exceed the cavity lengths. As the cavities operate at sequential harmonics of a basic repetition frequency, phase synchronism can be maintained over a relatively wide injection phase window without undue beam emittance growth. It is shown that use of radial vanes can allow cavity designs with significantly smaller radii, as compared with simple cylindrical cavities. Preliminary beam transport studies show that acceptable extraction and focusing of a proton beam after cyclic motion in this accelerator should be possible. Progress is also reported on design and tests of a four-cavity electron counterpart accelerator for experiments to study effects on beam quality arising from variations injection phase window width. This device is powered by four 500-MW pulsed amplifiers at 1500, 1800, 2100, and 2400 MHz that provide phase synchronous outputs, since they are driven from a with harmonics derived from a phase-locked 300 MHz source.

Jay L. Hirshfield

2011-12-27T23:59:59.000Z

422

SuperB Progress Report for Accelerator  

Science Conference Proceedings (OSTI)

This report details the progress made in by the SuperB Project in the area of the Collider since the publication of the SuperB Conceptual Design Report in 2007 and the Proceedings of SuperB Workshop VI in Valencia in 2008. With this document we propose a new electron positron colliding beam accelerator to be built in Italy to study flavor physics in the B-meson system at an energy of 10 GeV in the center-of-mass. This facility is called a high luminosity B-factory with a project name 'SuperB'. This project builds on a long history of successful e+e- colliders built around the world, as illustrated in Figure 1.1. The key advances in the design of this accelerator come from recent successes at the DAFNE collider at INFN in Frascati, Italy, at PEP-II at SLAC in California, USA, and at KEKB at KEK in Tsukuba Japan, and from new concepts in beam manipulation at the interaction region (IP) called 'crab waist'. This new collider comprises of two colliding beam rings, one at 4.2 GeV and one at 6.7 GeV, a common interaction region, a new injection system at full beam energies, and one of the two beams longitudinally polarized at the IP. Most of the new accelerator techniques needed for this collider have been achieved at other recently completed accelerators including the new PETRA-3 light source at DESY in Hamburg (Germany) and the upgraded DAFNE collider at the INFN laboratory at Frascati (Italy), or during design studies of CLIC or the International Linear Collider (ILC). The project is to be designed and constructed by a worldwide collaboration of accelerator and engineering staff along with ties to industry. To save significant construction costs, many components from the PEP-II collider at SLAC will be recycled and used in this new accelerator. The interaction region will be designed in collaboration with the particle physics detector to guarantee successful mutual use. The accelerator collaboration will consist of several groups at present universities and national laboratories. In Italy these may include INFN Frascati and the University of Pisa, in the United States SLAC, LBNL, BNL and several universities, in France IN2P3, LAPP, and Grenoble, in Russia BINP, in Poland Krakow University, and in the UK the Cockcroft Institute. The construction time for this collider is a total of about four years. The new tunnel can be bored in about a year. The new accelerator components can be built and installed in about 4 years. The shipping of components from PEP-II at SLAC to Italy will take about a year. A new linac and damping ring complex for the injector for the rings can be built in about three years. The commissioning of this new accelerator will take about a year including the new electron and positron sources, new linac, new damping ring, new beam transport lines, two new collider rings and the Interaction Region. The new particle physics detector can be commissioned simultaneously with the accelerator. Once beam collisions start for particle physics, the luminosity will increase with time, likely reaching full design specifications after about two to three years of operation. After construction, the operation of the collider will be the responsibility of the Italian INFN governmental agency. The intent is to run this accelerator about ten months each year with about one month for accelerator turn-on and nine months for colliding beams. The collider will need to operate for about 10 years to provide the required 50 ab{sup -1} requested by the detector collaboration. Both beams as anticipated in this collider will have properties that are excellent for use as sources for synchrotron radiation (SR). The expected photon properties are comparable to those of PETRA-3 or NSLS-II. The beam lines and user facilities needed to carry out this SR program are being investigated.

Biagini, M.E.; Boni, R.; Boscolo, M.; Buonomo, B.; Demma, T.; Drago, A.; Esposito, M.; Guiducci, S.; Mazzitelli, G.; Pellegrino, L.; Preger, M.A.; Raimondi, P.; Ricci, R.; Rotundo, U.; Sanelli, C.; Serio, M.; Stella, A.; Tomassini, S.; Zobov, M.; /Frascati; Bertsche, K.; Brachman, A.; /SLAC /Novosibirsk, IYF /INFN, Pisa /Pisa U. /Orsay, LAL /Annecy, LAPP /LPSC, Grenoble /IRFU, SPP, Saclay /DESY /Cockroft Inst. Accel. Sci. Tech. /U. Liverpool /CERN

2012-02-14T23:59:59.000Z

423

Accelerator and electrodynamics capability review  

Science Conference Proceedings (OSTI)

Los Alamos National Laboratory (LANL) uses capability reviews to assess the science, technology and engineering (STE) quality and institutional integration and to advise Laboratory Management on the current and future health of the STE. Capability reviews address the STE integration that LANL uses to meet mission requirements. The Capability Review Committees serve a dual role of providing assessment of the Laboratory's technical contributions and integration towards its missions and providing advice to Laboratory Management. The assessments and advice are documented in reports prepared by the Capability Review Committees that are delivered to the Director and to the Principal Associate Director for Science, Technology and Engineering (PADSTE). Laboratory Management will use this report for STE assessment and planning. LANL has defined fifteen STE capabilities. Electrodynamics and Accelerators is one of the seven STE capabilities that LANL Management (Director, PADSTE, technical Associate Directors) has identified for review in Fiscal Year (FY) 2010. Accelerators and electrodynamics at LANL comprise a blend of large-scale facilities and innovative small-scale research with a growing focus on national security applications. This review is organized into five topical areas: (1) Free Electron Lasers; (2) Linear Accelerator Science and Technology; (3) Advanced Electromagnetics; (4) Next Generation Accelerator Concepts; and (5) National Security Accelerator Applications. The focus is on innovative technology with an emphasis on applications relevant to Laboratory mission. The role of Laboratory Directed Research and Development (LDRD) in support of accelerators/electrodynamics will be discussed. The review provides an opportunity for interaction with early career staff. Program sponsors and customers will provide their input on the value of the accelerator and electrodynamics capability to the Laboratory mission.

Jones, Kevin W [Los Alamos National Laboratory

2010-01-01T23:59:59.000Z

424

The Advanced Manufacturing Jobs and Innovation Accelerator ...  

Science Conference Proceedings (OSTI)

Page 1. Advanced Manufacturing Jobs and Innovation Accelerator Challenge – Application Guide & Document Checklist 1 of 4 ...

2012-06-26T23:59:59.000Z

425

Interconnection Network for Tightly Coupled Accelerators Architecture  

Science Conference Proceedings (OSTI)

In recent years, heterogeneous clusters using accelerators have entered widespread use in high-performance computing systems. In such clusters, inter-node communication between accelerators normally requires several memory copies via CPU memory, which ... Keywords: PCI Express, Interconnect for accelerators, GPU cluster, Accelerator computing, Remote DMA

Toshihiro Hanawa, Yuetsu Kodama, Taisuke Boku, Mitsuhisa Sato

2013-08-01T23:59:59.000Z

426

Observation of the Rayleigh-Taylor instability in ablatively accelerated foils  

SciTech Connect

We present the first absolute, two-dimensionally resolved measurements of areal mass density of laser-driven ablatively accelerated foils, which show the Rayleigh-Taylor instability developing from initial mass perturbations. Our data are near simulation results which predict that the Rayleigh-Taylor growth rate is less than classical. The measurements sometimes show development of significant areal mass inhomogeneity in a direction perpendicular to that of the initially imposed perturbations.

Grun, J.; Emery, M.H.; Kacenjar, S.; Opal, C.B.; McLean, E.A.; Obenschain, S.P.; Ripin, B.H.; Schmitt, A.

1984-10-01T23:59:59.000Z

427

Pulse - Accelerator Science in Medicine  

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

t the forefront of biomedical research, medical scientists use particle accelerators to explore the structure of biological molecules. They use the energy that charged particles emit when accelerated to nearly the speed of light to create one of the brightest lights on earth, 30 times more powerful than the sun and focused on a pinpoint. t the forefront of biomedical research, medical scientists use particle accelerators to explore the structure of biological molecules. They use the energy that charged particles emit when accelerated to nearly the speed of light to create one of the brightest lights on earth, 30 times more powerful than the sun and focused on a pinpoint. Deciphering the structure of proteins is key to understanding biological processes and healing disease. To determine a proteinÂ’s structure, researchers direct the beam from an accelerator called a synchrotron through a protein crystal. The crystal scatters the beam onto a detector. From the pattern of scattering, computers calculate the position of every atom in the protein molecule and create a 3-D image of the molecule.

428

Mass and Lifetime Measurements in Storage Rings  

Science Conference Proceedings (OSTI)

Masses of nuclides covering a large area of the chart of nuclides can be measured in storage rings where many ions circulate at the same time. In this paper the recent progress in the analysis of Schottky mass spectrometry data is presented as well as the technical improvements leading to higher accuracy for isochronous mass measurements with a time-of-flight detector. The high sensitivity of the Schottky method down to single ions allows to measure lifetimes of nuclides by observing mother and daughter nucleus simultaneously. In this way we investigated the decay of bare and H-like 140Pr. As we could show the lifetime can be even shortened compared to those of atomic nuclei despite of a lower number of electrons available for internal conversion or electron capture.All these techniques will be implemented with further improvements at the storage rings of the new FAIR facility at GSI in the future.

Weick, H.; Beckert, K.; Beller, P.; Bosch, F.; Dimopoulou, C.; Kozhuharov, C.; Kurcewicz, J.; Mazzocco, M.; Nociforo, C.; Nolden, F.; Steck, M.; Sun, B.; Winkler, M. [Gesellschaft fuer Schwerionenforschung mbH, 64291 Darmstadt (Germany); Brandau, C.; Chen, L.; Geissel, H.; Knoebel, R.; Litvinov, S. A.; Litvinov, Yu. A.; Scheidenberger, C. [Gesellschaft fuer Schwerionenforschung mbH, 64291 Darmstadt (Germany); II. Phys. Institut, Justus-Liebig-Universitaet Giessen, 35392 Giessen (Germany)] (and others)

2007-05-22T23:59:59.000Z

429

Market Acceleration | Department of Energy  

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

Market Acceleration Market Acceleration Market Acceleration Photo of the Wanapum Dam. Hydropower contributes significantly to the nation's renewable energy portfolio; over the last decade, the United States obtained nearly 7% of its electricity from hydropower sources. Already the largest source of renewable electricity in the United States, there remains a vast untapped resource potential in hydropower. To achieve its vision of supporting 15% of our nation's electricity needs from water power by 2030, the Water Power Program works to address environmental and regulatory barriers that prevent significant amounts of deployment; to assess and quantify the value of hydropower to the nation's electric grid and its ability to integrate other variable renewable energy technologies; and to develop a vibrant U.S.

430

Accelerated Aging of Roofing Surfaces  

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

Accelerated aging of roofing surfaces Accelerated aging of roofing surfaces Hugo Destaillats, Ph.D. Lawrence Berkeley National Laboratory HDestaillats@LBL.gov (510) 486-5897 http://HeatIsland.LBL.gov April 4, 2013 Development of Advanced Building Envelope Surface Materials & Integration of Artificial Soiling and Weathering in a Commercial Weatherometer New York Times, 30 July 2009 2010 2012 Challenge: speed the development of high performance building envelope materials that resist soiling, maintain high solar reflectance, and save energy 2 | Building Technologies Office eere.energy.gov

431

Overtone Mobility Spectrometry: Part 1. Experimental Observations  

E-Print Network (OSTI)

introduce a new approach for isolating ions having specific mobilities (or collision cross sections). IonsARTICLES Overtone Mobility Spectrometry: Part 1. Experimental Observations Ruwan T. Kurulugama, Indiana University, Bloomington, Indiana, USA A new method that allows a linear drift tube to be operated

Clemmer, David E.

432

High mass resolution time of flight mass spectrometer for measuring products in heterogeneous catalysis in highly sensitive microreactors  

Science Conference Proceedings (OSTI)

We demonstrate a combined microreactor and time of flight system for testing and characterization of heterogeneous catalysts with high resolution mass spectrometry and high sensitivity. Catalyst testing is performed in silicon-based microreactors which have high sensitivity and fast thermal response. Gas analysis is performed with a time of flight mass spectrometer with a modified nude Bayard-Alpert ionization gauge as gas ionization source. The mass resolution of the time of flight mass spectrometer using the ion gauge as ionization source is estimated to m/{Delta}m > 2500. The system design is superior to conventional batch and flow reactors with accompanying product detection by quadrupole mass spectrometry or gas chromatography not only due to the high sensitivity, fast temperature response, high mass resolution, and fast acquisition time of mass spectra but it also allows wide mass range (0-5000 amu in the current configuration). As a demonstration of the system performance we present data from ammonia oxidation on a Pt thin film showing resolved spectra of OH and NH{sub 3}.

Andersen, T.; Jensen, R.; Christensen, M. K.; Chorkendorff, I. [Department of Physics, Danish National Research Foundation's Center for Individual Nanoparticle Functionality (CINF), Technical University of Denmark, Building 312, DK-2800 Kgs. Lyngby (Denmark); Pedersen, T.; Hansen, O. [Department of Micro- and Nanotechnology, Technical University of Denmark, DTU Nanotech Building 345 East, DK-2800 Kgs. Lyngby (Denmark)

2012-07-15T23:59:59.000Z

433

SOME ASPECTS OF THE PROSPECTIVE EXPERIMENTAL USE OF THE STANFORD TWO-MILE ACCELERATOR  

DOE Green Energy (OSTI)

Eleven papers dealing with photon beams from the accelerator, use of hydrogen bubble chambers and spark chambers, a storage ring for 10-Bev muons, muon beams and -p scattering experiments, mass analysis of highenergy accelerator beams, the search for intermediate bosons and heavy leptons, particle yields arising from decay of short-lived intermediate particles, and conjectures on the effects of Regge poles on Drell processes are included. Separate abstracts were prepared for the eleven papers. (D.C.W.)

Chinowsky, W.; DeWire, J.W.; Lichtenberg, D.B.; Masek, G.; Murray, J.J.; Perl, M.; Schwartz, M.; Tinlot, J.; Trilling, G.

1962-01-01T23:59:59.000Z

434

Ultrasensitive Identification of Localization Variants of Modified Peptides Using Ion Mobility Spectrometry  

Science Conference Proceedings (OSTI)

Localization of the modification sites on peptides is challenging, particularly when multiple modifications or mixtures of localization isomers (variants) are involved. Such variants commonly coelute in liquid chromatography and may be undistinguishable in tandem mass spectrometry (MS/MS) for lack of unique fragments. Here, we have resolved the variants of singly and doubly phosphorylated peptides employing drift tube ion mobility spectrometry (IMS) coupled to time-of-flight mass spectrometry. Even with a moderate IMS resolving power of ~80, substantial separation was achieved for both 2+ and 3+ ions normally generated by electrospray ionization, including for the variant indistinguishable by MS/MS. Variants often exhibit a distribution of 3-D conformers, which can be adjusted for optimum IMS separation by prior field heating of ions in a funnel trap. The peak assignments were confirmed using MS/MS after IMS separation, but known species could be identified using just the ion mobility "tag". Avoiding the MS/MS step lowers the detection limit of localization variants to electron transfer dissociation in an Orbitrap MS.

Ibrahim, Yehia M.; Shvartsburg, Alexandre A.; Smith, Richard D.; Belov, Mikhail E.

2011-05-28T23:59:59.000Z

435

Accelerator Operators and Software Development  

SciTech Connect

At Thomas Jefferson National Accelerator Facility, accelerator operators perform tasks in their areas of specialization in addition to their machine operations duties. One crucial area in which operators contribute is software development. Operators with programming skills are uniquely qualified to develop certain controls applications because of their expertise in the day-to-day operation of the accelerator. Jefferson Lab is one of the few laboratories that utilizes the skills and knowledge of operators to create software that enhances machine operations. Through the programs written; by operators, Jefferson Lab has improved machine efficiency and beam availability. Because many of these applications involve automation of procedures and need graphical user interfaces, the scripting language Tcl and the Tk toolkit have been adopted. In addition to automation, some operator-developed applications are used for information distribution. For this purpose, several standard web development tools such as perl, VBScript, and ASP are used. Examples of applications written by operators include injector steering, spin angle changes, system status reports, magnet cycling routines, and quantum efficiency measurements. This paper summarizes how the unique knowledge of accelerator operators has contributed to the success of the Jefferson Lab control system. *This work was supported by the U.S. DOE contract No. DE-AC05-84-ER40150.

April Miller; Michele Joyce

2001-11-01T23:59:59.000Z

436

Thomas Jefferson National Accelerator Facility  

Science Conference Proceedings (OSTI)

The Thomas Jefferson National Accelerator Facility (Jefferson Lab) in Newport News, Virginia, USA, is one of ten national laboratories under the aegis of the Office of Science of the U.S. Department of Energy (DOE). It is managed and operated by Jefferson Science Associates, LLC. The primary facility at Jefferson Lab is the Continuous Electron Beam Accelerator Facility (CEBAF) as shown in an aerial photograph in Figure 1. Jefferson Lab was created in 1984 as CEBAF and started operations for physics in 1995. The accelerator uses superconducting radio-frequency (srf) techniques to generate high-quality beams of electrons with high-intensity, well-controlled polarization. The technology has enabled ancillary facilities to be created. The CEBAF facility is used by an international user community of more than 1200 physicists for a program of exploration and study of nuclear, hadronic matter, the strong interaction and quantum chromodynamics. Additionally, the exceptional quality of the beams facilitates studies of the fundamental symmetries of nature, which complement those of atomic physics on the one hand and of high-energy particle physics on the other. The facility is in the midst of a project to double the energy of the facility and to enhance and expand its experimental facilities. Studies are also pursued with a Free-Electron Laser produced by an energy-recovering linear accelerator.

Joseph Grames, Douglas Higinbotham, Hugh Montgomery

2010-09-01T23:59:59.000Z

437

Accelerators for Intensity Frontier Research  

SciTech Connect

In 2008, the Particle Physics Project Prioritization Panel identified three frontiers for research in high energy physics, the Energy Frontier, the Intensity Frontier, and the Cosmic Frontier. In this paper, I will describe how Fermilab is configuring and upgrading the accelerator complex, prior to the development of Project X, in support of the Intensity Frontier.

Derwent, Paul; /Fermilab

2012-05-11T23:59:59.000Z

438

GPU-accelerated path rendering  

Science Conference Proceedings (OSTI)

For thirty years, resolution-independent 2D standards (e.g. PostScript, SVG) have depended on CPU-based algorithms for the filling and stroking of paths. Advances in graphics hardware have largely ignored accelerating resolution-independent 2D graphics ... Keywords: OpenGL, path rendering, stencil buffer, vector graphics

Mark J. Kilgard; Jeff Bolz

2012-11-01T23:59:59.000Z

439

Accelerating lattice reduction with FPGAs  

Science Conference Proceedings (OSTI)

We describe an FPGA accelerator for the Kannan-Fincke-Pohst enumeration algorithm (KFP) solving the Shortest Lattice Vector Problem (SVP). This is the first FPGA implementation of KFP specifically targeting cryptographically relevant dimensions. In order ... Keywords: FPGA, euclidean lattices, shortest vector problem

Jérémie Detrey; Guillaume Hanrot; Xavier Pujol; Damien Stehlé

2010-08-01T23:59:59.000Z

440

Petawatt pulsed-power accelerator  

DOE Patents (OSTI)

A petawatt pulsed-power accelerator can be driven by various types of electrical-pulse generators, including conventional Marx generators and linear-transformer drivers. The pulsed-power accelerator can be configured to drive an electrical load from one- or two-sides. Various types of loads can be driven; for example, the accelerator can be used to drive a high-current z-pinch load. When driven by slow-pulse generators (e.g., conventional Marx generators), the accelerator comprises an oil section comprising at least one pulse-generator level having a plurality of pulse generators; a water section comprising a pulse-forming circuit for each pulse generator and a level of monolithic triplate radial-transmission-line impedance transformers, that have variable impedance profiles, for each pulse-generator level; and a vacuum section comprising triplate magnetically insulated transmission lines that feed an electrical load. When driven by LTD generators or other fast-pulse generators, the need for the pulse-forming circuits in the water section can be eliminated.

Stygar, William A. (Albuquerque, NM); Cuneo, Michael E. (Albuquerque, NM); Headley, Daniel I. (Albuquerque, NM); Ives, Harry C. (Albuquerque, NM); Ives, legal representative; Berry Cottrell (Albuquerque, NM); Leeper, Ramon J. (Albuquerque, NM); Mazarakis, Michael G. (Albuquerque, NM); Olson, Craig L. (Albuquerque, NM); Porter, John L. (Sandia Park, NM); Wagoner; Tim C. (Albuquerque, NM)

2010-03-16T23:59:59.000Z

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.


441

The BErkeley Lab Laser Accelerator (BELLA): A 10 GeV Laser Plasma Accelerator  

E-Print Network (OSTI)

The BErkeley Lab Laser Accelerator (BELLA):A 10 GeV Laser Plasma Accelerator W.P. Leemans ' , R.of the design of a 10 GeV laser plasma accelerator (LPA)

Leemans, W.P.

2011-01-01T23:59:59.000Z

442

Particle Acceleration in Geospace and Its Association With Solar Events  

E-Print Network (OSTI)

Particle acceleration is a prominent feature of the geomagnetic storm, which is the prime dynamic process in Geospace - the near-Earth space environment. Magnetic storms have their origin in solar events, which are transient disturbances of the solar atmosphere and radiation that propagate as variations of the solar wind fields and particles through interplanetary space to the Earth's orbit. During magnetic storms, ions of both solar wind origin and terrestrial origin are accelerated and form an energetic ring current in the inner magnetosphere. This current has global geomagnetic effects, which have both physical and technical implications. Recently it has been shown that large magnetic storms, which exhibit an unusually energized ionospheric plasma component, are closely associated with coronal mass ejections (CMEs). This implies a cause-effect chain connecting solar events through CMEs and the solar wind with the acceleration of terrestrial ion populations whicheventually constitute the main source of global geomagnetic disturbances. Here we present spacecraft observations related to storm-time particle acceleration and assess the observations in the framework of causes and effects of solar-terrestrial relationships.

I. A. Daglis; W. I. Axford; E. T. Sarris; S. Livi; B. Wilken

1997-01-01T23:59:59.000Z

443

Self-accelerated brane Universe with warped extra dimension  

E-Print Network (OSTI)

We propose a cosmological model which exhibits the phenomenon of self-acceleration: the Universe is attracted to the phase of accelerated expansion at late times even in the absence of the cosmological constant. The self-acceleration is inevitable in the sense that it cannot be neutralized by any negative explicit cosmological constant. The model is formulated in the framework of brane-world theories with a warped extra dimension. The key ingredient of the model is the brane-bulk energy transfer which is carried by bulk vector fields with a sigma-model-like boundary condition on the brane. We explicitly find the 5-dimensional metric corresponding to the late-time de Sitter expansion on the brane; this metric describes an AdS_5 black hole with growing mass. The present value of the Hubble parameter implies the scale of new physics of order 1 TeV, where the proposed model has to be replaced by putative UV-completion. The mechanism leading to the self-acceleration has AdS/CFT interpretation as occurring due to specific dynamics of conformal matter interacting with external "electric" fields. The Universe expansion history predicted by the model is distinguishable from the standard LambdaCDM cosmology.

D. S. Gorbunov; S. M. Sibiryakov

2008-04-14T23:59:59.000Z

444

Survey of Advanced Dielectric Wakefield Accelerators  

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

out wakefield accelerator research. Wakefield Acceleration at AATF The AATF had an electron beam produced by an L- band thermionic RF gun followed by two traveling-wave linac...

445

Science Accelerator Widget | Data.gov  

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

Science Accelerator Widget BusinessUSA DataTools Apps Challenges Let's Talk BusinessUSA You are here Data.gov Communities BusinessUSA Data Science Accelerator Widget...

446

Research Accelerator Division | Neutron Science | ORNL  

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

Kevin Jones The Research Accelerator Division is responsible for operation of the SNS accelerator complex, which consists of a negative hydrogen-ion injector, a 1 GeV linear...

447

Research Accelerator Division | ORNL Neutron Sciences  

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

Kevin Jones. The Research Accelerator Division (RAD) is responsible for operation of the SNS accelerator complex, which consists of a negative hydrogen-ion injector, a 1 GeV linear...

448

Elucidating mechanisms of accelerated neurological aging  

E-Print Network (OSTI)

C. (2005). Mechanisms of aging in senescence- accelerated2.2 Strain-specific aging gene-expression profiles…………………..C. (2005). Mechanisms of aging in senescence-accelerated

Greenhall, Jennifer Anne

2008-01-01T23:59:59.000Z

449

Accelerator and Fusion Research Division  

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

Outreach and Diversity Highlights Safety Other Sites and Labs Intramural Outreach and Diversity Highlights Safety Other Sites and Labs Intramural Historical photo of Laboratory founder and cyclotron inventor Ernest Orlando Lawrence at his desk OUR SCIENTIFIC PROGRAMS Accelerator Physics for the ALS Center for Beam Physics LOASIS Laboratory Fusion Science and Ion Beam Technology Superconducting Magnets Free Electron Laser R&D News: AFRD's Jean-Luc Vay and former AFRD scientist Kwang-Je Kim share the US Particle Accelerator School Prize. Andre Anders places two articles among the year's top 30 in the Journal of Applied Physics. AFRD personnel win an R&D 100 in a joint project with industry; the laser at the heart of BELLA sets a world record for laser power. Employees: Safety tips regarding the mountain lion are available. The results from our two most recent Self-Assessment Focus Groups are up, covering emergency preparedness and ergonomics while working offsite.

450

Fermilab's Accelerator and Research Divisions  

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

July 19, 1996 July 19, 1996 Number 14 Fixed-target experimenters not only expect Fermilab's Accelerator and Research Divisions to turn water into wine-they need 10 different vintages. Providing beam to fixed-target experiments presents the challenge of converting high-inten- sity protons into 10 separate beams of varying intensities and particles, from kaons to neu- trinos. The Accelerator Division generates and splits the beam, and then hands the protons off to the Research Division, which converts them into beams of different particles. The process begins with a breath of hydrogen gas. Eventually the hydrogen atoms lose their outer electrons and become a stream of protons-the formation of the beam. Physicists measure two characteristics of the beam: its energy (eV) and its intensity. Intensity

451

Radiological Training for Accelerator Facilities  

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

8-2002 8-2002 May 2002 Change Notice No 1. with Reaffirmation January 2007 DOE HANDBOOK RADIOLOGICAL TRAINING FOR ACCELERATOR FACILITIES U.S. Department of Energy AREA TRNG Washington, D.C. 20585 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. TS This document has been reproduced from the best available copy. Available to DOE and DOE contractors from ES&H Technical Information Services, U.S. Department of Energy, (800) 473-4375, fax: (301) 903-9823. Available to the public from the U.S. Department of Commerce, Technology Administration, National Technical Information Service, Springfield, VA 22161; (703) 605-6000. Change Notice 1. Radiological Safety Training for Accelerator Facilities

452

Standards Acceleration to Jumpstart Adoption of Cloud ...  

Science Conference Proceedings (OSTI)

... Standards Acceleration to Jumpstart Adoption of Cloud Computing (SAJACC). The goal of the SAJACC initiative is to drive ...

2013-07-02T23:59:59.000Z

453

Available Technologies: Acceleration of Carbon Dioxide ...  

APPLICATIONS OF TECHNOLOGY: Carbon dioxide capture and sequestration; ADVANTAGES: Accelerated capture of carbon dioxide; Effective at extremely dilute (nanomolar ...

454

Fermi National Accelerator Laboratory Technology Marketing ...  

Fermi National Accelerator Laboratory Technology Marketing Summaries. Here you’ll find marketing summaries for technologies available for licensing ...

455

Accelerating Innovation Webinar Series - Energy Innovation ...  

Accelerating Innovation Webinar Series. In partnership with the Battelle Commercialization Council, the Energy Innovation Portal is hosting an ...

456

SLAC National Accelerator Laboratory Technology Marketing ...  

Energy Analysis; Energy Storage; Geothermal; Hydrogen and Fuel Cell; Hydropower, Wave and Tidal; ... SLAC National Accelerator Laboratory Technology Marketing Summaries.

457

Fermi National Accelerator Laboratory Technologies Available ...  

... Energy Innovation Portal on Google; Bookmark Fermi National Accelerator Laboratory Technologies Available for Licensing - Energy Innovation Portal ...

458

Accelerated Weathering of Fluidized Bed Steam Reformation ...  

Science Conference Proceedings (OSTI)

Sep 16, 2007 ... Accelerated Weathering of Fluidized Bed Steam Reformation Material Under Hydraulically Unsaturated Conditions by E.M. Pierce ...

459

SLAC National Accelerator Laboratory Technology Marketing ...  

Energy Analysis; Energy Storage; Geothermal; Hydrogen and Fuel Cell; Hydropower, Wave and Tidal; ... SLAC National Accelerator Laboratory Technology M ...

460

Accelerated Materials Evaluation for Nuclear Application Utilizing ...  

Science Conference Proceedings (OSTI)

Jul 15, 2013... of accelerated nuclear materials testing for fission and fusion reactors. Presentations combining experiment with theory, modeling and ...

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

Powering Up America: Accelerating an Interoperable Smart ...  

Science Conference Proceedings (OSTI)

Powering Up America: Accelerating an Interoperable Smart Grid (+18 FTE, +$5,000,000). image: Shutterstock, copyright Photoroller. Challenge. ...

2010-10-05T23:59:59.000Z

462

Accelerating Observers, Area and Entropy  

E-Print Network (OSTI)

We consider an explicit example of a process, where the entropy carried by radiation through an accelerating two-plane is proportional to the decrease in the area of that two-plane even when the two-plane is not a part of any horizon of spacetime. Our results seem to support the view that entropy proportional to area is possessed not only by horizons but by all spacelike two-surfaces of spacetime.

Makela, J

2005-01-01T23:59:59.000Z

463

Accelerating Observers, Area and Entropy  

E-Print Network (OSTI)

We consider an explicit example of a process, where the entropy carried by radiation through an accelerating two-plane is proportional to the decrease in the area of that two-plane even when the two-plane is not a part of any horizon of spacetime. Our results seem to support the view that entropy proportional to area is possessed not only by horizons but by all spacelike two-surfaces of spacetime.

Jarmo Makela

2005-06-16T23:59:59.000Z

464

Accelerators  

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

Aceleradores Avanzar Volver Principal ESTOY PERDIDO Los aceleradores le resuelven a los fsicos dos problemas. En primer lugar, dado que todas las partculas se comportan como...

465

Energy Measurement in a Plasma Wakefield Accelerator  

SciTech Connect

In the E-167 plasma wakefield acceleration experiment, electrons with an initial energy of 42GeV are accelerated in a meter-scale lithium plasma. Particles are leaving plasma with a large energy spread. To determine the spectrum of the accelerated particles, a two-plane spectrometer has been set up.

Ischebeck, R

2007-07-06T23:59:59.000Z

466

Voltage regulation in linear induction accelerators  

DOE Patents (OSTI)

Improvement in voltage regulation in a Linear Induction Accelerator wherein a varistor, such as a metal oxide varistor when it is placed in parallel with the beam accelerating cavity and the magnetic core. The non-linear properties of the varistor result in a more stable voltage across the beam accelerating cavity than with a conventional compensating resistance.

Parsons, W.M.

1991-03-19T23:59:59.000Z

467

Voltage regulation in linear induction accelerators  

DOE Patents (OSTI)

Improvement in voltage regulation in a linear induction accelerator wherein a varistor, such as a metal oxide varistor, is placed in parallel with the beam accelerating cavity and the magnetic core is disclosed. The non-linear properties of the varistor result in a more stable voltage across the beam accelerating cavity than with a conventional compensating resistance. 4 figs.

Parsons, W.M.

1992-12-29T23:59:59.000Z

468

Current Sheet Canting in Pulsed Electromagnetic Accelerators  

E-Print Network (OSTI)

Current Sheet Canting in Pulsed Electromagnetic Accelerators Thomas Edward Markusic A DISSERTATION #12;Current Sheet Canting in Pulsed Electromagnetic Accelerators Prepared by: Thomas Edward Markusic of current sheet canting in pulsed electromagnetic accelerators is the de- parture of the plasma sheet

Choueiri, Edgar

469

Accelerating Clean-up at Savannah River | Department of Energy  

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

Accelerating Clean-up at Savannah River Accelerating Clean-up at Savannah River Accelerating Clean-up at Savannah River More Documents & Publications Integrated Project Team RM...

470

Fermilab | Plan for the Future | Fermilab accelerator complex...  

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

The Fermilab accelerator complex Fermilab's accelerator complex comprises ten particle accelerators and storage rings. It produces the world's most powerful, high-energy neutrino...