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Note: This page contains sample records for the topic "imaging 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.


1

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

2

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

3

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

4

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

5

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

6

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

7

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

8

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

9

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

10

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

11

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

12

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 ...

13

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...

14

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

15

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

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

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

16

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

17

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

18

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,...

19

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

20

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

Note: This page contains sample records for the topic "imaging 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

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

22

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

23

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

24

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 ...

25

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 ...

26

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

27

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

28

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

29

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

30

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

31

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

32

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

33

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

34

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

35

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

36

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...

37

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...

38

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

39

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

40

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

Note: This page contains sample records for the topic "imaging 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

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

42

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

43

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

44

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

45

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

46

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

47

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

48

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

49

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

50

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...

51

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

52

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

53

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

54

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

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

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

58

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

59

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

60

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

Note: This page contains sample records for the topic "imaging 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

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

62

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

63

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)

64

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.

65

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

66

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

67

Imaging Spectrometry of Tropospheric Ozone and Water Vapor  

E-Print Network (OSTI)

Imaging spectrometry has the potential of remotely detecting atmospheric trace gases on the basis of their absorption of radiation. Ozone absorbs particulary in the ultraviolet and visible range of the spectrum, whereas water vapor has strong absorption features in the near infrared. Hence, spectrometry is expected to be a promising tool to extract these trace gas contents in a given air column by using the correlation between cumulative trace gas amount and absorption strength in the sensor channels located in the absorption bands. New mathematical methods of channel selection and method evaluation for measuring atmospheric trace gases are presented. Three already known and four new differential absorption techniques are evaluated by using MODTRAN2 simulations of the radiance spectrum at the sensor level and an analytical error propagation analysis. Finally, the best methods and channel combinations are selected and applied to AVIRIS data of Central Switzerland. The spatial ozone distribution could be estimated over water in a qualitative manner, whereas the total column water vapor content could be quantified over land with an accuracy of about 6%.

Daniel Schläpfer; Klaus I. Itten; Johannes Keller

1995-01-01T23:59:59.000Z

68

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

69

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

70

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

71

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

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

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

75

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

76

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

77

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

78

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

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 "imaging 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

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

86

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...

87

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

88

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

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

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

91

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.

92

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

93

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

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

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

96

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

97

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

98

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

99

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.

100

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

Note: This page contains sample records for the topic "imaging 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

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

102

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

103

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

104

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

105

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

106

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

107

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

108

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

109

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

110

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

111

{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

112

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 ...

113

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

114

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

115

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

116

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

117

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

118

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...

119

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

120

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

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121

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 ...

122

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

123

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

124

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

125

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

126

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

127

Development of high-spatial and high-mass resolution mass spectrometric imaging (MSI) and its application to the study of small metabolites and endogenous molecules of plants  

SciTech Connect

High-spatial and high-mass resolution laser desorption ionization (LDI) mass spectrometric (MS) imaging technology was developed for the attainment of MS images of higher quality containing more information on the relevant cellular and molecular biology in unprecedented depth. The distribution of plant metabolites is asymmetric throughout the cells and tissues, and therefore the increase in the spatial resolution was pursued to reveal the localization of plant metabolites at the cellular level by MS imaging. For achieving high-spatial resolution, the laser beam size was reduced by utilizing an optical fiber with small core diameter (25 ?m) in a vacuum matrix-assisted laser desorption ionization-linear ion trap (vMALDI-LTQ) mass spectrometer. Matrix application was greatly improved using oscillating capillary nebulizer. As a result, single cell level spatial resolution of ~ 12 ?m was achieved. MS imaging at this high spatial resolution was directly applied to a whole Arabidopsis flower and the substructures of an anther and single pollen grains at the stigma and anther were successfully visualized. MS imaging of high spatial resolution was also demonstrated to the secondary roots of Arabidopsis thaliana and a high degree of localization of detected metabolites was successfully unveiled. This was the first MS imaging on the root for molecular species. MS imaging with high mass resolution was also achieved by utilizing the LTQ-Orbitrap mass spectrometer for the direct identification of the surface metabolites on the Arabidopsis stem and root and differentiation of isobaric ions having the same nominal mass with no need of tandem mass spectrometry (MS/MS). MS imaging at high-spatial and high-mass resolution was also applied to cer1 mutant of the model system Arabidopsis thaliana to demonstrate its usefulness in biological studies and reveal associated metabolite changes in terms of spatial distribution and/or abundances compared to those of wild-type. The spatial distribution of targeted metabolites, mainly waxes and flavonoids, was systematically explored on various organs, including flowers, leaves, stems, and roots at high spatial resolution of ~ 12-50 ?m and the changes in the abundance level of these metabolites were monitored on the cer1 mutant with respect to the wild-type. This study revealed the metabolic biology of CER1 gene on each individual organ level with very detailed high spatial resolution. The separate MS images of isobaric metabolites, i.e. C29 alkane vs. C28 aldehyde could be constructed on both genotypes from MS imaging at high mass resolution. This allows tracking of abundance changes for those compounds along with the genetic mutation, which is not achievable with low mass resolution mass spectrometry. This study supported previous hypothesis of molecular function of CER1 gene as aldehyde decarbonylase, especially by displaying hyper accumulation of aldehydes and C30 fatty acid and decrease in abundance of alkanes and ketones in several plant organs of cer1 mutant. The scope of analytes was further directed toward internal cell metabolites from the surface metabolites of the plant. MS profiling and imaging of internal cell metabolites were performed on the vibratome section of Arabidopsis leaf. Vibratome sectioning of the leaf was first conducted to remove the surface cuticle layer and it was followed by enzymatic treatment of the section to induce the digestion of primary cell walls, middle lamella, and expose the internal cells underneath to the surface for detection with the laser by LDI-MS. The subsequent MS imaging onto the enzymatically treated vibratome section allowed us to map the distribution of the metabolites in the internal cell layers, linolenic acid (C18:3 FA) and linoleic acid (C18:2 FA). The development of an assay for relative quantification of analytes at the single subcellular/organelle level by LDI-MS imaging was attempted and both plausibility and significant obstacles were seen. As a test system, native plant organelle, chloroplasts isolated from the spinach leaves were used

Jun, Ji Hyun

2011-11-30T23:59:59.000Z

128

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

129

NMIS with Imaging and Gamma Ray Spectrometry for Pu, HEU, HE and Other Materials  

SciTech Connect

The Nuclear Material Identification System (NMIS) has been under development at ORNL and the National Nuclear Security Administration (NNSA) Y-12 National Security Complex since 1984. In the mid-1990s, what is now the US Department of Energy (DOE) Office of Nuclear Verification (ONV) realized that it was a useful technology for future arms control treaty applications and supported further development of the system. In 2004, fast-neutron imaging was incorporated into the system. In 2007, the ONV decided to develop a fieldable version of the system, designated as FNMIS, for potential use in future treaties. The FNMIS is being developed to be compatible with the eventual incorporation of gamma-ray spectrometry and an information barrier. This report addresses how and what attributes could be determined by the FNMIS system with gamma-ray spectrometry. The NMIS is a time-dependent coincidence system that incorporates tomographic imaging (including mapping of the fission sites) and gamma-ray spectrometry. It utilizes a small, lightweight (30 lb), portable deuterium-tritium (DT) neutron (14.1 MeV) generator (4 x 10{sup 7} neutrons/second) for active interrogation and can also perform passive interrogation. A high-purity germanium (HPGe) gamma-ray detector with multichannel analysis can be utilized in conjunction with the source for active interrogation or passively. The system uses proton recoil scintillators: 32 small 2.5 x 2.5 x 10.2-cm-thick plastic scintillators for imaging and at least two 2 x 2 arrays of 27 x 27 x 10-cm-thick plastic scintillators that detect induced fission radiation. The DT generator contains an alpha detector that time and directionally tags a fan beam of some of the neutrons emitted and subdivides it into pixels. A fast (1 GHz) time correlation processor measures the time-dependent coincidence among all detectors in the system. A computer-controlled scanner moves the small detectors and the source appropriately for scanning a target object for imaging. The system is based on detection of transmitted 14.1 MeV neutrons, fission neutrons, and gamma rays from spontaneous, inherent source fission of the target, fission neutrons and gamma rays induced by the external DT source, gamma rays from natural emissions of uranium and plutonium, and induced gamma-ray emission by the interaction of the 14.1 MeV neutrons from the DT source. The NMIS can and has been used with a time-tagged californium spontaneous fission source. It has also been used with pulsed interrogation sources such as LINACs, DT, and deuterium-deuterium (DD) sources. This system is uniquely suited for detection of shielded highly enriched uranium (HEU), plutonium, and other special nuclear materials and detection of high explosives (HE) and chemical agents. The NMIS will be adapted to utilize a trusted processor that incorporates information barrier and authentication techniques using open software and then be useful in some international applications for materials whose characteristics may be classified. The proposed information barrier version of the NMIS system would consist of detectors and cables, the red (classified side) computer system, which processes the data, and the black (unclassified side) computer, which handles the computer interface. The system could use the 'IB wrapper' concept proposed by Los Alamos National Laboratory and the software integrity (digital signatures) system proposed by Sandia. Since it is based entirely on commercially available components, the entire system, including NMIS data acquisition boards, can be built with commercial off-the-shelf components. This system is being developed into a fieldable system (FNMIS) for potential arms control treaties by the ONV. The system will be modularly constructed with the RF shielded modules connected to the processor by appropriate control and signal cable in metal conduit. The FNMIS is presently being designed for eventual incorporation of gamma-ray spectrometry and an information barrier to protect classified information. The system hardware and software can be configu

Mihalczo, John T [ORNL; Mullens, James Allen [ORNL

2012-03-01T23:59:59.000Z

130

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

131

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

132

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

133

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.

134

Development of Quantitative Measurement of Fuel Mass Distribution Using Planar Imaging Technique  

Science Conference Proceedings (OSTI)

The quantified fuel mass distribution of a spray was obtained from laser induced fluorescence images with optical patternation. In the dense spray region, however, the emitted fluorescence signal is significantly attenuated in the path of the detector ... Keywords: Imaging method, Laser induced fluorescence (LIF), Mass distribution, Signal Attenuation, Spray

H. Koh; K. Jung; Y. Yoon; K. Lee; K. -S. Jeong

2006-04-01T23:59:59.000Z

135

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

136

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

137

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

138

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

139

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

140

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

Note: This page contains sample records for the topic "imaging 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

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

142

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

143

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

144

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

145

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

146

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

147

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.

148

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.

149

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

150

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

151

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

152

Attributes from NMIS Time Coincidence, Fast-Neutron Imaging, Fission Mapping, And Gamma-Ray Spectrometry Data  

Science Conference Proceedings (OSTI)

This work tests a systematic procedure for analyzing data acquired by the Nuclear Materials Identification System (NMIS) at Oak Ridge National Laboratory with fast-neutron imaging and high-purity germanium (HPGe) gamma spectrometry capabilities. NMIS has been under development by the US Department of Energy Office of Nuclear Verification since the mid-1990s, and prior to that by the National Nuclear Security Administration Y-12 National Security Complex, with NMIS having been used at Y-12 for template matching to confirm inventory and receipts. In this present work, a complete set of NMIS time coincidence, fast-neutron imaging, fission mapping, and HPGe gamma-ray spectrometry data was obtained from Monte Carlo simulations for a configuration of fissile and nonfissile materials. The data were then presented for analysis to someone who had no prior knowledge of the unknown object to accurately determine the description of the object by applying the previously-mentioned procedure to the simulated data. The best approximation indicated that the unknown object was composed of concentric cylinders: a void inside highly enriched uranium (HEU) (84.7 {+-} 1.9 wt % {sup 235}U), surrounded by depleted uranium, surrounded by polyethylene. The final estimation of the unknown object had the correct materials and geometry, with error in the radius estimates of material regions varying from 1.58% at best and 4.25% at worst; error in the height estimates varied from 2% to 12%. The error in the HEU enrichment estimate was 5.9 wt % (within 2.5{sigma} of the true value). The accuracies of the determinations could be adequate for arms control applications. Future work will apply this iterative reconstructive procedure to other unknown objects to further test and refine it.

Swift, Alicia L [ORNL; Grogan, Brandon R [ORNL; Mullens, James Allen [ORNL; Hayward, J P [University of Tennessee, Knoxville (UTK); Mihalczo, John T [ORNL

2012-01-01T23:59:59.000Z

153

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

154

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

155

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

156

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.

157

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

158

Direct Gravitational Imaging of Intermediate Mass Black Holes in Extragalactic Halos  

E-Print Network (OSTI)

A galaxy halo may contain a large number of intermediate mass black holes (IMBHs) with masses in the range of 10^{2-6} solar mass. We propose to directly detect these IMBHs by observing multiply imaged QSO-galaxy or galaxy-galaxy strong lens systems in the submillimeter bands with high angular resolution. The silhouette of an IMBH in the lensing galaxy halo would appear as either a monopole-like or a dipole-like variation at the scale of the Einstein radius against the Einstein ring of the dust-emitting region surrounding the QSO. We use a particle tagging technique to dynamically populate a Milky Way-sized dark matter halo with black holes, and show that the surface mass density and number density of IMBHs have power-law dependences on the distance from the center of the host halo if smoothed on a scale of ~ 1 kpc. Most of the black holes orbiting close to the center are freely roaming as they have lost their dark matter hosts during infall due to tidal stripping. Next generation submillimeter telescopes with high angular resolution (solar mass in a lensing galaxy that harbours a O(10^9) solar mass supermassive black hole in its nucleus.

Kaiki Taro Inoue; Valery Rashkov; Joseph Silk; Piero Madau

2013-01-22T23:59:59.000Z

159

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

160

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 ...

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161

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

162

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

163

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

164

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

165

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.

166

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

167

NIST Image Gallery: Image Details  

Science Conference Proceedings (OSTI)

... 72 DPI Image © 150 DPI Image © 300 DPI Image ©. Title: Metrology, Basic Units; Mass; Electronic Kilogram. Description ...

168

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

169

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

170

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

171

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

172

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

173

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

174

Exquisite Nova Light Curves from the Solar Mass Ejection Imager (SMEI)  

E-Print Network (OSTI)

We present light curves of three classical novae (KT Eridani, V598 Puppis, V1280 Scorpii) and one recurrent nova (RS Ophiuchi) derived from data obtained by the Solar Mass Ejection Imager (SMEI) on board the Coriolis satellite. SMEI provides near complete sky-map coverage with precision visible-light photometry at 102-minute cadence. The light curves derived from these sky maps offer unprecedented temporal resolution around, and especially before, maximum light, a phase of the nova eruption normally not covered by ground-based observations. They allow us to explore fundamental parameters of individual objects including the epoch of the initial explosion, the reality and duration of any pre-maximum halt (found in all three fast novae in our sample), the presence of secondary maxima, speed of decline of the initial light curve, plus precise timing of the onset of dust formation (in V1280 Sco) leading to estimation of the bolometric luminosity, white dwarf mass and object distance. For KT Eri, Liverpool Telescop...

Hounsell, R; Hick, P P; Buffington, A; Jackson, B V; Clover, J M; Shafter, A W; Darnley, M J; Mawson, N R; Steele, I A; Evans, A; Eyres, S P S; O'Brien, T J

2010-01-01T23:59:59.000Z

175

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

176

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

177

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

178

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

179

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

180

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

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


181

INNER HELIOSPHERIC FLUX ROPE EVOLUTION VIA IMAGING OF CORONAL MASS EJECTIONS  

Science Conference Proceedings (OSTI)

Understanding the evolution of flux ropes in coronal mass ejections (CMEs) is of importance both to the scientific and technological communities. Scientifically their presence is critical to models describing CME launch and they likely play a role in CME evolution. Technologically they are the major contributor to severe geomagnetic storms. Using a new processing technique on the STEREO/SECCHI heliospheric imaging data, we have tracked a magnetic flux rope observed by the Wind spacecraft in December 2008 to its origins observed by coronagraphs. We thereby establish that the cavity in the classic three-part coronagraph CME is the feature that becomes the magnetic cloud. This implies that the bright material ahead of the cavity is piled-up coronal or solar wind material. We track the evolution of the cavity en-route and find that its structure transforms from concave inward (curving away from the Sun) to concave outward (toward the Sun) around 0.065 AU from the Sun. The pileup was tracked and its leading edge remained concave inward throughout its journey. Two other CMEs in January 2009 are also inspected and a similar cavity is observed in each, suggesting that they too each contained a flux rope. The results presented here are the first direct observation, through continuous tracking, associating a particular flux rope observed in situ with the same flux rope before ejection from the corona. We speculate that detailed heliospheric imagery of CMEs may lead to a means by which flux ropes can be identified remotely in the heliosphere.

Howard, T. A.; DeForest, C. E. [Southwest Research Institute, 1050 Walnut Street, Suite 300, Boulder, CO 80302 (United States)

2012-02-10T23:59:59.000Z

182

Supercomputing: Eye-Opening Possibilities in Imaging | Department of Energy  

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

Supercomputing: Eye-Opening Possibilities in Imaging Supercomputing: Eye-Opening Possibilities in Imaging Supercomputing: Eye-Opening Possibilities in Imaging September 20, 2013 - 5:00pm Addthis This overlay of mass spectrometry images shows the spatial distribution of three different kind of lipids across a whole mouse cross-section. Lipids act as the structural components of cell membranes and are responsible for energy storage, among other things. | Photo courtesy of Wolfgang Reindl (Berkeley Lab). This overlay of mass spectrometry images shows the spatial distribution of three different kind of lipids across a whole mouse cross-section. Lipids act as the structural components of cell membranes and are responsible for energy storage, among other things. | Photo courtesy of Wolfgang Reindl (Berkeley Lab).

183

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

184

Detection of masses in mammogram images using CNN, geostatistic functions and SVM  

Science Conference Proceedings (OSTI)

Breast cancer occurs with high frequency among the world's population and its effects impact the patients' perception of their own sexuality and their very personal image. This work presents a computational methodology that helps specialists detect breast ... Keywords: Cellular neural networks, Computer-aided detection, Geostatistical functions, Mammogram, Support vector machines

Wener Borges Sampaio; Edgar Moraes Diniz; Aristófanes Corrêa Silva; Anselmo Cardoso de Paiva; Marcelo Gattass

2011-08-01T23:59:59.000Z

185

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.

186

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

187

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.

188

OpenMSI: A Science Gateway to Sort Through Bio-Imaging's Big Datasets  

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

OpenMSI: A Science OpenMSI: A Science Gateway to Sort Through Bio-Imaging's Big Datasets OpenMSI: A Science Gateway to Sort Through Bio-Imaging's Big Datasets August 27, 2013 | Tags: Basic Energy Sciences (BES), Carver, Computer Science, Dirac, Hopper, Life Sciences, Science Gateways, Visualization Group Contact: Linda Vu, +1 510 495 2402, lvu@lbl.gov OpenMSINERSC.jpg This overlay of mass spectrometry images shows the spatial distribution of three different kind of lipids across a whole mouse cross-section. Lipids act as the structural components of cell membranes and are responsible for energy storage, among other things. Image credit: Wolfgang Reindl (Berkeley Lab). Using cutting-edge mass spectrometry imaging (MSI) technology, scientists can study tissues, cell cultures and bacterial colonies in unprecedented

189

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

190

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

191

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

192

AUTOMATICALLY DETECTING AND TRACKING CORONAL MASS EJECTIONS. I. SEPARATION OF DYNAMIC AND QUIESCENT COMPONENTS IN CORONAGRAPH IMAGES  

Science Conference Proceedings (OSTI)

Automated techniques for detecting and tracking coronal mass ejections (CMEs) in coronagraph data are of ever increasing importance for space weather monitoring and forecasting. They serve to remove the biases and tedium of human interpretation, and provide the robust analysis necessary for statistical studies across large numbers of observations. An important requirement in their operation is that they satisfactorily distinguish the CME structure from the background quiescent coronal structure (streamers, coronal holes). Many studies resort to some form of time differencing to achieve this, despite the errors inherent in such an approach-notably spatiotemporal crosstalk. This article describes a new deconvolution technique that separates coronagraph images into quiescent and dynamic components. A set of synthetic observations made from a sophisticated model corona and CME demonstrates the validity and effectiveness of the technique in isolating the CME signal. Applied to observations by the LASCO C2 and C3 coronagraphs, the structure of a faint CME is revealed in detail despite the presence of background streamers that are several times brighter than the CME. The technique is also demonstrated to work on SECCHI/COR2 data, and new possibilities for estimating the three-dimensional structure of CMEs using the multiple viewing angles are discussed. Although quiescent coronal structures and CMEs are intrinsically linked, and although their interaction is an unavoidable source of error in any separation process, we show in a companion paper that the deconvolution approach outlined here is a robust and accurate method for rigorous CME analysis. Such an approach is a prerequisite to the higher-level detection and classification of CME structure and kinematics.

Morgan, Huw [Sefydliad Mathemateg a Ffiseg, Prifysgol Aberystwyth, Ceredigion, Cymru, SY23 3BZ (United Kingdom); Byrne, Jason P.; Habbal, Shadia Rifai, E-mail: hmorgan@aber.ac.uk [Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822 (United States)

2012-06-20T23:59:59.000Z

193

Three Dimensional Molecular Imaging for Lignocellulosic Materials  

DOE Green Energy (OSTI)

components sequestered in the rigid cell walls of plants. A detailed chemical and structural understanding of this pre-enzymatic processing in space and time was the focus of this program. We worked to develop new imaging strategies that produce real-time molecular speciation information in situ; extract sub-surface information about the effects of processing; and follow the spatial and temporal characteristics of the molecular species in the matrix and correlate this complex profile with saccharification. Spatially correlated SIMS and Raman imaging were used to provide high quality, high resolution subcellular images of Miscanthus cross sections. Furthermore, the combination of information from the mass spectrometry and Raman scattering allows specific chemical assignments of observed structures, difficult to assign from either imaging approach alone and lays the foundation for subsequent heterocorrelated imaging experiments targeted at more challenging biological systems, such as the interacting plant-microbe systems relevant to the rhizosphere.

Bohn, Paul W.; Sweedler, Jonathan V.

2011-06-09T23:59:59.000Z

194

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

195

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; ...

196

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...

197

Imaging  

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

Imaging Print Imaging Print The wavelengths of soft x-ray photons (1-15 nm) are very well matched to the creation of "nanoscopes" capable of probing the interior structure of biological cells and inorganic mesoscopic systems.Topics addressed by soft x-ray imaging techniques include cell biology, nanomagnetism, environmental science, and polymers. The tunability of synchrotron radiation is absolutely essential for the creation of contrast mechanisms. Cell biology CAT scans are performed in the "water window" (300-500 eV). Nanomagnetism studies require the energy range characteristic of iron, cobalt, and nickel (600-900 eV). Mid- and far-infrared (energies below 1 eV) microprobes using synchrotron radiation are being used to address problems such as chemistry in biological tissues, chemical identification and molecular conformation, environmental biodegradation, mineral phases in geological and astronomical specimens, and electronic properties of novel materials. Infrared synchrotron radiation is focused through, or reflected from, a small spot on the specimen and then analyzed using a spectrometer. Tuning to characteristic vibrational frequencies serves as a sensitive fingerprint for molecular species. Images of the various species are built up by raster scanning the specimen through the small illuminated spot.

198

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

199

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

200

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

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


201

Extending the frontiers of mass spectrometric instrumentation and methods  

SciTech Connect

The focus of this dissertation is two-fold: developing novel analysis methods using mass spectrometry and the implementation and characterization of a novel ion mobility mass spectrometry instrumentation. The novel mass spectrometry combines ion trap for ion/ion reactions coupled to an ion mobility cell. The long term goal of this instrumentation is to use ion/ion reactions to probe the structure of gas phase biomolecule ions. The three ion source - ion trap - ion mobility - qTOF mass spectrometer (IT - IM - TOF MS) instrument is described. The analysis of the degradation products in coal (Chapter 2) and the imaging plant metabolites (Appendix III) fall under the methods development category. These projects use existing commercial instrumentation (JEOL AccuTOF MS and Thermo Finnigan LCQ IT, respectively) for the mass analysis of the degraded coal products and the plant metabolites, respectively. The coal degradation paper discusses the use of the DART ion source for fast and easy sample analysis. The sample preparation consisted of a simple 50 fold dilution of the soluble coal products in water and placing the liquid in front of the heated gas stream. This is the first time the DART ion source has been used for analysis of coal. Steven Raders under the guidance of John Verkade came up with the coal degradation projects. Raders performed the coal degradation reactions, worked up the products, and sent them to me. Gregg Schieffer developed the method and wrote the paper demonstrating the use of the DART ion source for the fast and easy sample analysis. The plant metabolite imaging project extends the use of colloidal graphite as a sample coating for atmospheric pressure LDI. DC Perdian and I closely worked together to make this project work. Perdian focused on building the LDI setup whereas Schieffer focused on the MSn analysis of the metabolites. Both Perdian and I took the data featured in the paper. Perdian was the primary writer of the paper and used it as a chapter in his dissertation. Perdian and Schieffer worked together to address the revisions and publish it in Rapid Communications in Mass Spectrometry Journal.

Schieffer, Gregg

2010-12-15T23:59:59.000Z

202

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

203

Hadamard transform spectrometry: A new analytical technique; Progress report, Second year, March 15, 1992--November 15, 1992  

SciTech Connect

The document is divided into 4 parts: Hadamard transform photoacoustic spectrometry and depth profiling; Hadamard transform imaging with a 2D Hadamard encoding mask (Raman image using pararosaniline hydrochloride); Hadamard transform Raman spectrometry; and work on the growth of VO{sub 2}(s) crystals for Hadamard masking material. 13 figs, refs.

Fateley, W.G.; Hammaker, R.M.

1992-11-15T23:59:59.000Z

204

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

205

Multispectral thermal imaging  

SciTech Connect

Many remote sensing applications rely on imaging spectrometry. Here the authors use imaging spectrometry for thermal and multispectral signatures measured from a satellite platform enhanced with a combination of accurate calibrations and on-board data for correcting atmospheric distortions. The approach is supported by physics-based end-to-end modeling and analysis, which permits a cost-effective balance between various hardware and software aspects. The goal is to develop and demonstrate advanced technologies and analysis tools toward meeting the needs of the customer; at the same time, the attributes of this system can address other applications in such areas as environmental change, agriculture, and volcanology.

Weber, P.G.; Bender, S.C.; Borel, C.C.; Clodius, W.B.; Smith, B.W. [Los Alamos National Lab., NM (United States). Space and Remote Sensing Sciences Group; Garrett, A.; Pendergast, M.M. [Westinghouse Savannah River Corp., Aiken, SC (United States). Savannah River Technology Center; Kay, R.R. [Sandia National Lab., Albuquerque, NM (United States). Monitoring Systems and Technology Center

1998-12-01T23:59:59.000Z

206

THE DEFLECTION OF THE TWO INTERACTING CORONAL MASS EJECTIONS OF 2010 MAY 23-24 AS REVEALED BY COMBINED IN SITU MEASUREMENTS AND HELIOSPHERIC IMAGING  

SciTech Connect

In 2010 May 23-24, Solar Dynamics Observatory (SDO) observed the launch of two successive coronal mass ejections (CMEs), which were subsequently tracked by the SECCHI suite on board STEREO. Using the COR2 coronagraphs and the heliospheric imagers (HIs), the initial direction of both CMEs is determined to be slightly west of the Sun-Earth line. We derive the CME kinematics, including the evolution of the CME expansion until 0.4 AU. We find that, during the interaction, the second CME decelerates from a speed above 500 km s{sup -1} to 380 km s{sup -1}, the speed of the leading edge of the first CME. STEREO observes a complex structure composed of two different bright tracks in HI2-A but only one bright track in HI2-B. In situ measurements from Wind show an 'isolated' interplanetary CME, with the geometry of a flux rope preceded by a shock. Measurements in the sheath are consistent with draping around the transient. By combining remote-sensing and in situ measurements, we determine that this event shows a clear instance of deflection of two CMEs after their collision, and we estimate the deflection of the first CME to be about 10 Degree-Sign toward the Sun-Earth line. The arrival time, arrival speed, and radius at Earth of the first CME are best predicted from remote-sensing observations taken before the collision of the CMEs. Due to the over-expansion of the CME after the collision, there are few, if any, signs of interaction in in situ measurements. This study illustrates that complex interactions during the Sun-to-Earth propagation may not be revealed by in situ measurements alone.

Lugaz, N.; Farrugia, C. J. [Space Science Center, University of New Hampshire, Durham, NH (United States); Davies, J. A.; Davis, C. J. [RAL Space, STFC Rutherford Appleton Laboratory, Chilton (United Kingdom); Moestl, C. [Space Science Laboratory, University of California, Berkeley, CA (United States); Roussev, I. I. [Yunnan Astronomical Observatory, Chinese Academy of Sciences, Kunming 650011, Yunnan (China); Temmer, M. [Kanzelhoehe Observatory-IGAM, Institute of Physics, University of Graz, A-8010 Graz (Austria)

2012-11-01T23:59:59.000Z

207

Three Dimensional Molecular Imaging for Lignocellulosic Materials  

SciTech Connect

The development of high efficiency, inexpensive processing protocols to render biomass components into fermentable substrates for the sequential processing of cell wall components into fuels and important feedstocks for the biorefinery of the future is a key goal of the national roadmap for renewable energy. Furthermore, the development of such protocols depends critically on detailed knowledge of the spatial and temporal infiltration of reagents designed to remove and separate the phenylpropenoid heteropolymer (lignin) from the processable sugar components sequestered in the rigid cell walls of plants. A detailed chemical and structural understanding of this pre-enzymatic processing in space and time was the focus of this program. We worked to develop new imaging strategies that produce real-time molecular speciation information in situ; extract sub-surface information about the effects of processing; and follow the spatial and temporal characteristics of the molecular species in the matrix and correlate this complex profile with saccharification. Spatially correlated SIMS and Raman imaging were used to provide high quality, high resolution subcellular images of Miscanthus cross sections. Furthermore, the combination of information from the mass spectrometry and Raman scattering allows specific chemical assignments of observed structures, difficult to assign from either imaging approach alone and lays the foundation for subsequent heterocorrelated imaging experiments targeted at more challenging biological systems, such as the interacting plant-microbe systems relevant to the rhizosphere.

Bohn, Paul W.; Sweedler, Jonathan V.

2011-06-09T23:59:59.000Z

208

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

209

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

210

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

211

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

212

The Extremely Red, Young L Dwarf PSO J318-22: A Free-Floating Planetary-Mass Analog to Directly Imaged Young Gas-Giant Planets  

E-Print Network (OSTI)

We have used Pan-STARRS1 to discover an extremely red late-L dwarf, which has (J-K)_MKO = 2.84 and (J-K)_2MASS = 2.78, making it the reddest known field dwarf and second only to 2MASS J1207-39b among substellar companions. Near-IR spectroscopy shows a spectral type of L7 and reveals a triangular H-band continuum and weak alkali (K I and Na I) lines, hallmarks of low surface gravity. Near-IR astrometry from the Hawaii Infrared Parallax Program gives a distance of 24.6+/-1.4 pc and indicates a much fainter J-band absolute magnitude than field L dwarfs. The position and kinematics of PSO J318-22 point to membership in the beta Pictoris moving group. Evolutionary models give a temperature of 1160 (-40,+30) K and a mass of 6.5 (-1.0, +1.3) Mjup, making PSO J318-22 one of the lowest mass free-floating objects in the solar neighborhood. This object adds to the growing list of low-gravity field L dwarfs and is the first to be strongly deficient in methane relative to its estimated temperature. Comparing their spectra...

Liu, Michael C; Deacon, Niall R; Allers, Katelyn N; Dupuy, Trent J; Kotson, Michael C; Aller, Kimberly M; Burgett, W S; Chambers, K C; Draper, P W; Hodapp, K W; Jedicke, R; Kudritzki, R -P; Metcalfe, N; Morgan, J S; Kaiser, N; Price, P A; Tonry, J L; Wainscoat, R J

2013-01-01T23:59:59.000Z

213

Press Pass - Press Release - Higgs mass constraints  

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

imagesHiggs-mass-constraints-Aug2008.html Tevatron Experiments Double-Team Higgs Boson Joint CDF, DZero effort lands Fermilab in Higgs territory Batavia, Ill.--Scientists...

214

Press Pass - Press Release - Higgs mass constraints  

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

-constraints-20100726-images.html Fermilab experiments narrow allowed mass range for Higgs boson Batavia, Ill.New constraints on the elusive Higgs particle are more stringent...

215

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

216

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

217

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

218

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

219

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 ...

220

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

Note: This page contains sample records for the topic "imaging 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

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

222

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.

223

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

224

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.

225

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...

226

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

227

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

228

NIST Image Gallery: Image Details  

Science Conference Proceedings (OSTI)

... Image Gallery : Image Details. 72 DPI Image 150 DPI Image No 300 DPI Version. Title: Frequency Comb, Ultrafast Laser. ...

229

NIST Image Gallery: Image Details  

Science Conference Proceedings (OSTI)

... Image Gallery : Image Details. 72 DPI Image 150 DPI Image No 300 DPI Version. Title: Iron-Based Superconductors. Description ...

230

NIST Image Gallery: Image Details  

Science Conference Proceedings (OSTI)

... Image Gallery : Image Details. 72 DPI Image 150 DPI Image No 300 DPI Version. Title: Space Weather Forecasts. Description ...

231

NIST Image Gallery: Image Details  

Science Conference Proceedings (OSTI)

... Image Gallery : Image Details. 72 DPI Image 150 DPI Image No 300 DPI Version. Title: Organic Solar Power. Description ...

232

NIST Image Gallery: Image Details  

Science Conference Proceedings (OSTI)

... 72 DPI Image © 150 DPI Image © 300 DPI Image ©. Title: Nanotechnology; Biotechnology/Health; Nanocrystals; Hwang. ...

233

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

234

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...

235

Imaging and differentiation of mouse embryo tissues by ToF-SIMS  

SciTech Connect

Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS) equipped with a gold ion gun was used to image mouse embryos and differentiate tissue types (brain, spinal cord, skull, rib, heart and liver). Embryos were paraffin-embedded and then de-paraffinized. The robustness and repeatability of the method was determined by analyzing nine tissue slices from three different embryos over a period of several weeks. Using Principal Component Analysis (PCA) to reduce the spectral data generated by ToF-SIMS, histopathologically identified tissue types of the mouse embryos can be differentiated based on the characteristic differences in their mass spectra. These results demonstrate the ability of ToF-SIMS to determine subtle chemical differences even in fixed histological specimens.

Wu, L; Lu, X; Kulp, K; Knize, M; Berman, E; Nelson, E; Felton, J; Wu, K J

2006-06-16T23:59:59.000Z

236

Amplitude and phase modulation (AM?PM) wide?band photothermal spectrometry. I. Theory  

Science Conference Proceedings (OSTI)

Amplitude and phase modulation (AM?PM) wide?band photothermal spectrometry is a new technique of excitation and signal recovery with extensive applications in thermal?wave imaging using linear photoacoustic and photothermal techniques. The excitation waveform consists of the superposition of two orthogonal amplitude?modulated frequency sweeps

J. F. Power

1990-01-01T23:59:59.000Z

237

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

238

NIST Image Gallery: Image Details  

Science Conference Proceedings (OSTI)

... 72 DPI Image © 150 DPI Image © 300 DPI Image ©. Title: Quantum Physics; Quantum Communications; Ultrafast Photon Detector; Nam. ...

239

NIST Image Gallery: Image Details  

Science Conference Proceedings (OSTI)

... 72 DPI Image © 150 DPI Image © 300 DPI Image ©. Title: Energy; Fossil Fuels;Distillation Curves for Complex Fuel Mixtures. ...

240

NIST Image Gallery: Image Details  

Science Conference Proceedings (OSTI)

... 72 DPI Image © 150 DPI Image © 300 DPI Image ©. Title: Scanning Electron Microscope with Spin Polarization Analysis. ...

Note: This page contains sample records for the topic "imaging 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

NIST Image Gallery: Image Details  

Science Conference Proceedings (OSTI)

... nist.gov. 72 DPI Image © 150 DPI Image © 300 DPI Image ©. Title: Public safety & Smart Grid. Description: Electrical engineer ...

242

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 ...

243

NIST Image Gallery: Image Details  

Science Conference Proceedings (OSTI)

... Image Gallery : Image Details. 72 DPI Image No 150 DPI Version 300 DPI Image. Title: Ultrafast Laser Speeds Up Quest for Atomic Control. ...

244

NIST Image Gallery: Image Details  

Science Conference Proceedings (OSTI)

... Image Gallery : Image Details. 72 DPI Image 150 DPI Image No 300 DPI Version. Title: House; Trees. Description: *BFRL. Subjects (names): ...

245

NIST Image Gallery: Image Details  

Science Conference Proceedings (OSTI)

... 72 DPI Image © 150 DPI Image © 300 DPI Image ©. Title: New Imaging Tool is Boon to Fuel Cell Research. Description: NIST ...

246

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...

247

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

248

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

249

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

250

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

251

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

252

NIST Image Gallery: Image Details  

Science Conference Proceedings (OSTI)

... 72 DPI Image © 150 DPI Image © 300 DPI Image ©. Title: Homeland Security; Chem., Bio, and Other Threats; Standards for Radiation Detection. ...

253

NIST Image Gallery: Image Details  

Science Conference Proceedings (OSTI)

... Image Gallery : Image Details. No 72 DPI Version No 150 DPI Version 300 DPI Image. Title: Gold Nano Anchors Put Nanowires in Their Place. ...

254

NIST Image Gallery: Image Details  

Science Conference Proceedings (OSTI)

... 72 DPI Image © 150 DPI Image © 300 DPI Image ©. Title: Iron-based and Copper-Oxide High-Temperature Superconductors. ...

255

NIST Image Gallery: Image Details  

Science Conference Proceedings (OSTI)

... Title: Metrology, Basic Units; Mass; Kilogram (blue). ... MEL, mass measurements, kilogram, SI, metric system, measurement artifact, weight,. ...

256

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

257

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

258

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

259

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

260

NIST Image Gallery: Image Details  

Science Conference Proceedings (OSTI)

... 72 DPI Image 150 DPI Image No 300 DPI Version. Title: NIST Finds that Ethanol-Loving Bacteria Accelerate Cracking of Pipeline Steels. ...

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


261

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

262

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.

263

NIST Image Gallery: Image Details  

Science Conference Proceedings (OSTI)

... Title: Scanning tunneling microscope; Semiconductor; Spintronics. Description: [Left] A high resolution STM image of a manganese ...

264

NIST Image Gallery: Image Details  

Science Conference Proceedings (OSTI)

... Title: Nanotechnology--Nanomanufacturing; Optical Nano Vision. Description: A new optical imaging technology under ...

265

SPIE Medical Imaging Medical Imaging  

E-Print Network (OSTI)

1 SPIE Medical Imaging 2006 1 Medical Imaging Fundamentals Kenneth H. Wong, Ph.D. Division of Computer Assisted Interventions and Medical Robotics (CAIMR) Imaging Science and Information Systems (ISIS) Center Department of Radiology Georgetown University SPIE Medical Imaging 2006 2 Main Themes · Describe

Miga, Michael I.

266

Predicting cognitive data from medical images using sparse linear regression  

Science Conference Proceedings (OSTI)

We present a new framework for predicting cognitive or other continuous-variable data from medical images. Current methods of probing the connection between medical images and other clinical data typically use voxel-based mass univariate approaches. ...

Benjamin M. Kandel, David A. Wolk, James C. Gee, Brian Avants

2013-06-01T23:59:59.000Z

267

Mercury's Protoplanetary Mass  

E-Print Network (OSTI)

Major element fractionation among chondrites has been discussed for decades as ratios relative to Si or Mg. Recently, by expressing ratios relative to Fe, I discovered a new relationship admitting the possibility that ordinary chondrite meteorites are derived from two components, a relatively oxidized and undifferentiated, primitive component and a somewhat differentiated, planetary component, with oxidation state like the highly reduced enstatite chondrites, which I suggested was identical to Mercury's complement of lost elements. Here, on the basis of that relationship, I derive expressions, as a function of the mass of planet Mercury and the mass of its core, to estimate the mass of Mercury's lost elements, the mass of Mercury's alloy and rock protoplanetary core, and the mass of Mercury's gaseous protoplanet. Although Mercury's mass is well known, its core mass is not, being widely believed to be in the range of 70-80 percent of the planet mass. For a core mass of 75 percent, the mass of Mercury's lost elements is about 1.32 times the mass of Mercury, the mass of the alloy and rock protoplanetary core is about 2.32 times the mass of Mercury, and the mass of the gaseous protoplanet of Mercury is about 700 times the mass of Mercury. Circumstantial evidence is presented in support of the supposition that Mercury's lost elements is identical to the planetary component of ordinary chondrite formation.

J. Marvin Herndon

2004-10-01T23:59:59.000Z

268

Pushing the Frontier of High-Definition Ion Mobility Spectrometry Using FAIMS  

Science Conference Proceedings (OSTI)

Differential ion mobility spectrometry (FAIMS) separates ions in gases based on the difference between their mobilities in strong and weak electric fields, captured directly employing a periodic waveform with dissimilar profiles in opposite polarities. As that difference is not tightly correlated with the ion size or mass, FAIMS separations are generally quite orthogonal to both conventional IMS (based on the absolute ion mobility that reflects the physical ion size) and mass spectrometry (based on mass). Until a few years ago, that advantage was largely offset by poor FAIMS resolving power (?10–20), an order of magnitude below that achieved with conventional (drift-tube) IMS. This article summarizes the major recent technical developments that have raised FAIMS resolving power up to ?500. These include use of higher and more stable voltages provided by new waveform generators, novel buffer gas compositions comprising high helium or hydrogen fractions, and extended filtering times up to ?1 s. These advances have enabled previously unthinkable analyses such as broad baseline separations of peptide sequence inversions, localization variants (post-translationally modified peptides with differing PTM attachment sites) even for the larger “middle-down” peptides and smallest PTMs, and lipid regioisomers.

Shvartsburg, Alexandre A.; Anderson, Gordon A.; Smith, Richard D.

2013-05-03T23:59:59.000Z

269

NIST Image Gallery: Image Details  

Science Conference Proceedings (OSTI)

... Title: Metrology--Basic Units; Mass; Electronic Kilogram/Watt Balance Schematic. Description: In the NIST watt balance ...

270

NIST Image Gallery: Image Details  

Science Conference Proceedings (OSTI)

... Title: Carbon Nanotube Measurements. Description: Scanning electron microscope image of 'cleaned' carbon nanotubes at NIST (color added for ...

271

NIST Image Gallery: Image Details  

Science Conference Proceedings (OSTI)

... Description: Engineering design image shows a cross-section of part of the planned ITER fusion reaction vessel. Diverter ...

272

Volatiles in hydrothermal fluids- A mass spectrometric study of fluid  

Open Energy Info (EERE)

Volatiles in hydrothermal fluids- A mass spectrometric study of fluid Volatiles in hydrothermal fluids- A mass spectrometric study of fluid inclusions from active geothermal systems Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Report: Volatiles in hydrothermal fluids- A mass spectrometric study of fluid inclusions from active geothermal systems Details Activities (4) Areas (4) Regions (0) Abstract: A system for analysis of inclusion gas contents based upon quadrupole mass spectrometry has been designed, assembled and tested during the first 7 months of funding. The system is currently being tested and calibrated using inclusions with known gas contents from active geothermal systems. Analyses are in progress on inclusions from the Salton Sea, Valles Caldera, Geysers, and Coso geothermal systems. Author(s): Mckibben, M. A.

273

Image Resources  

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

Mosaic of earth and sky images Mosaic of earth and sky images Image Resources Free image resources covering energy, environment, and general science. Here are some links to energy- and environment-related photographic databases. Berkeley Lab Photo Archive Berkeley Lab's online digital image collection. National Science Digital Library (NSDL) NSDL is the Nation's online library for education and research in science, technology, engineering, and mathematics. The World Bank Group Photo Library A distinctive collection of over 11,000 images that illustrate development through topics such as Agriculture, Education, Environment, Health, Trade and more. Calisphere Compiles the digital collections of libraries, museums, and cultural heritage organizations across California, and organizes them by theme, such

274

Elbow mass flow meter  

SciTech Connect

Elbow mass flow meter. The present invention includes a combination of an elbow pressure drop generator and a shunt-type mass flow sensor for providing an output which gives the mass flow rate of a gas that is nearly independent of the density of the gas. For air, the output is also approximately independent of humidity.

McFarland, Andrew R. (College Station, TX); Rodgers, John C. (Santa Fe, NM); Ortiz, Carlos A. (Bryan, TX); Nelson, David C. (Santa Fe, NM)

1994-01-01T23:59:59.000Z

275

NIST Image Gallery: Image Details  

Science Conference Proceedings (OSTI)

... on the availability of this image. Title: Tiny Tubes May Aid Pharmacuetical R&D. Description: NIST scientists used pairs of ...

276

NIST Image Gallery: Image Details  

Science Conference Proceedings (OSTI)

... Magneto-optical image of magnetic fields within a YBCO superconductor showing electrically ... PHY, High-Temp Superconductors See also http ...

277

NIST Image Gallery: Image Details  

Science Conference Proceedings (OSTI)

... Title: New Imaging Tool is Boon to Fuel Cell Research. ... water being produced and removed inside the maze-like solid housing of fuel cells under a ...

278

A Scanning Frequency Mode for Ion Cyclotron Mobility Spectrometry  

E-Print Network (OSTI)

A new operational mode for an ion cyclotron mobility spectrometry instrument is explored as a possibleA Scanning Frequency Mode for Ion Cyclotron Mobility Spectrometry Rebecca S. Glaskin, Stephen J that are applied to segmented regions of a circular drift tube. Ions with mobilities that are resonant

Clemmer, David E.

279

Nanometric Optical Imaging Frontiers in Chemical Imaging  

E-Print Network (OSTI)

Nanometric Optical Imaging Frontiers in Chemical Imaging Seminar Series Presented by... Professor thermal imaging, chemical delivery and other new horizons. Finally, as part of this lecture, Lewis

280

Mass independent kinetic energy reducing inlet system for vacuum environment  

Science Conference Proceedings (OSTI)

A particle inlet system comprises a first chamber having a limiting orifice for an incoming gas stream and a micrometer controlled expansion slit. Lateral components of the momentum of the particles are substantially cancelled due to symmetry of the configuration once the laminar flow converges at the expansion slit. The particles and flow into a second chamber, which is maintained at a lower pressure than the first chamber, and then moves into a third chamber including multipole guides for electromagnetically confining the particle. The vertical momentum of the particles descending through the center of the third chamber is minimized as an upward stream of gases reduces the downward momentum of the particles. The translational kinetic energy of the particles is near-zero irrespective of the mass of the particles at an exit opening of the third chamber, which may be advantageously employed to provide enhanced mass resolution in mass spectrometry.

Reilly, Peter T. A. [Knoxville, TN

2010-12-14T23:59:59.000Z

Note: This page contains sample records for the topic "imaging 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

Images, Video, & More  

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

Images, Video, & More Images BABAR Design drawings SLAC Image Gallery: BABAR SLAC Image Gallery: Aerial photos Videos Public lecture on "ANTIMATTER: What is it and where did it...

282

Thermogravimetry-Mass Spectrometry for Carbon Nanotube Detection in Complex Mixtures  

E-Print Network (OSTI)

In spite of the growth of the carbon nanotube (CNT) industry, there are no established analytical methods with which to detect or quantify CNTs in environmental matrices. Given that CNTs have relatively high thermal ...

Plata, Desiree Louise

283

Application of Mass Spectrometry on Quantitative Proteomics and Histone Post-Translational Modifications  

E-Print Network (OSTI)

Probable ATP-dependent RNA helicase DDX5 IPI00220373.3Probable ATP-dependent RNA helicase DDX5 IPI00023748.3IPI00215637.4 ATP-dependent RNA helicase DDX3X IPI00010700.2

Xiong, Lei

2011-01-01T23:59:59.000Z

284

A Mass Spectrometry Study of Isotope Separation in the Laser Plume  

E-Print Network (OSTI)

Attribution and Non-Proliferation Applications”, IEEETreaty on the Non-Proliferation of Nuclear Weapons (NPT)”,as detailed in the Non-Proliferation Treaty (NPT), is to

Suen, Timothy Wu

2012-01-01T23:59:59.000Z

285

Kinetics of laser pulse vaporization of uranium dioxide by mass spectrometry  

Science Conference Proceedings (OSTI)

Safety analyses of nuclear reactors require knowledge of the evaporation behavior of UO/sub 2/ at temperatures well above the melting point of 3140 K. In this study, rapid transient heating of a small spot on a UO/sub 2/ specimen was accomplished by a laser pulse, which generates a surface temperature excursion. This in turn vaporizes the target surface and the gas expands into vacuum. The surface temperature transient was monitored by a fast-response automatic optical pyrometer. The maximum surface temperatures investigated range from approx. 3700 K to approx. 4300 K. A computer program was developed to simulate the laser heating process and calculate the surface temperature evolution. The effect of the uncertainties of the high temperature material properties on the calculation was included in a sensitivity study for UO/sub 2/ vaporization. The measured surface temperatures were in satisfactory agreements.

Tsai, C.

1981-11-01T23:59:59.000Z

286

Mass Spectrometry Based Method Development for Elucidation of Protein Sequences, Structures and Post Translational Modifications  

E-Print Network (OSTI)

Covelli, I. ; Wolff, J. J. Bio. Chem. 1967, 242, 881-886.A. ; Yates, J. R. Curr. Opin. Chem. Bio. 2008, 12, 483-490.

Sun, Qingyu

2011-01-01T23:59:59.000Z

287

Anthropogenic particulate source characterization and source apportionment using aerosol time-of-flight mass spectrometry  

E-Print Network (OSTI)

vehicles, biomass burning, coal combustion, meat cooking,Arabia: biomass/biofuel burning and fossil fuel combustion,Arabia: biomass/biofuel burning and fossil fuel combustion,

Toner, Stephen Mark

2007-01-01T23:59:59.000Z

288

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...

289

Development and application of mass spectrometry-based metabolomics methods for disease biomarker identification  

E-Print Network (OSTI)

Human societies face diverse health challenges including a rapidly aging population, rising incidence of metabolic disease, and increasing antibiotic resistance. These problems involve complex interactions between genes ...

Tong, Lily Victoria

2008-01-01T23:59:59.000Z

290

New mass spectrometry techniques for studying physical chemistry of atmospheric heterogeneous processes  

E-Print Network (OSTI)

ion mode DESI and nano-DESI result in the formation of protonated molecules [M + H]+ and molecules cationised on metals, such as sodium [M + Na]+ adducts, while deprotonated [M Ã? H]Ã? molecules are observed+ ) reacts selectively with molecules (M) containing carbonyl groups, such as aldehydes and ketones [79

Nizkorodov, Sergey

291

Science of Signatures Workshop on Secondary Ion Mass Spectrometry (SIMS) Applications July 24, 2012  

SciTech Connect

The science of signatures focus areas are: (1) Radiological and Nuclear; (2) Chemical and Materials (including explosives); (3) Biological - Signatures of Disease and Health; (4) Energy; (5) Climate; and (6) Space.

Hickmott, Donald D [Los Alamos National Laboratory; Riciputi, Lee D [Los Alamos National Laboratory

2012-07-23T23:59:59.000Z

292

High resolution mass spectrometry method and system for analysis of whole proteins and other large molecules  

DOE Patents (OSTI)

A matrix assisted laser desorption/ionization (MALDI) method and related system for analyzing high molecular weight analytes includes the steps of providing at least one matrix-containing particle inside an ion trap, wherein at least one high molecular weight analyte molecule is provided within the matrix-containing particle, and MALDI on the high molecular weight particle while within the ion trap. A laser power used for ionization is sufficient to completely vaporize the particle and form at least one high molecular weight analyte ion, but is low enough to avoid fragmenting the high molecular weight analyte ion. The high molecular weight analyte ion is extracted out from the ion trap, and is then analyzed using a detector. The detector is preferably a pyrolyzing and ionizing detector.

Reilly, Peter T. A. (Knoxville, TN); Harris, William A. (Naperville, IL)

2010-03-02T23:59:59.000Z

293

Facilitation of protein 3-D structure determination using enhanced peptide amide deuterium exchange mass spectrometry (DXMS)  

E-Print Network (OSTI)

metalloproteinase inhibitor doxycycline investigated bymetalloproteinase inhibitor doxycycline investigated byand Nagasue N (2004) Doxycycline inhibits cell proliferation

Pantazatos, Dennis Peter

2006-01-01T23:59:59.000Z

294

A Mass Spectrometry Study of Isotope Separation in the Laser Plume  

E-Print Network (OSTI)

Proliferation of Nuclear Weapons (NPT)”, http: //www.un.org/end of the Cold War, nuclear weapons remain at the heart ofthe spread of nuclear weapons, analysis of nuclear materials

Suen, Timothy Wu

2012-01-01T23:59:59.000Z

295

Studies of Atmospheric Chemistry and Reaction Mechanisms Using Optical Spectroscopy and Mass Spectrometry  

E-Print Network (OSTI)

measurement system of peroxy radicals using a chemical amplification/laser-measurement system of peroxy radicals using a chemical amplification/laser-

Liu, Yingdi

2011-01-01T23:59:59.000Z

296

A Mass Spectrometry Study of Isotope Separation in the Laser Plume  

E-Print Network (OSTI)

as detailed in the Non-Proliferation Treaty (NPT), is toUnited Nations, “Treaty on the Non-Proliferation of Nuclear

Suen, Timothy Wu

2012-01-01T23:59:59.000Z

297

Characterization of the Molecular Composition of Secondary Organic Aerosols using High Resolution Mass Spectrometry  

E-Print Network (OSTI)

in secondary organic aerosol formation from isoprene, Proc.biogenic secondary organic aerosol, J. Phys. Chem. A, 112(in secondary organic aerosol, Environ. Sci. Technol. , 41(

Sellon, Rachel Elizabeth

2012-01-01T23:59:59.000Z

298

Computational mass spectrometry : algorithms for identification of peptides not present in protein databases  

E-Print Network (OSTI)

Pereira, W. -T. Liu, J. Ng, P. A. Pevzner, P. C. Dorrestein,11188, 2010. W. -T. Liu, J. Ng, D. Meluzzi, N. Bandeira, M.no. 11, pp. 4200-4209, J. Ng, N. Bandeira, W. -T. Liu, M.

Ng, Julio

2011-01-01T23:59:59.000Z

299

A Mass Spectrometry Study of Isotope Separation in the Laser Plume  

E-Print Network (OSTI)

Pakistan is exacerbated by concerns over both terrorist activity and the security of its rapidly increasing nuclear

Suen, Timothy Wu

2012-01-01T23:59:59.000Z

300

Does Information Have Mass?  

E-Print Network (OSTI)

Does information have mass? This question has been asked many times and there are many answers even on the Internet, including on Yahoo Answers. Usually the answer is "no". Attempts have been made to assess the physical mass of information by estimating the mass of electrons feeding the power-guzzling computers and devices making up the Internet, the result being around 50 gram. Other efforts to calculate the mass of information have assumed that each electron involved in signal transfer carries one bit of information, which makes the corresponding mass to be about 10^-5 gram. We address the fundamental question of minimum mass related to a bit of information from the angles of quantum physics and special relativity. Our results indicate that there are different answers depending on the physical situation, and sometimes the mass can even be negative. We tend to be skeptical about the earlier mass estimations, mentioned above, because our results indicate that the electron's mass does not play a role in any on...

Kish, Laszlo B

2013-01-01T23:59:59.000Z

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


301

Mass-Loaded Flows  

E-Print Network (OSTI)

A key process within astronomy is the exchange of mass, momentum, and energy between diffuse plasmas in many types of astronomical sources (including planetary nebulae, wind-blown bubbles, supernova remnants, starburst superwinds, and the intracluster medium) and dense, embedded clouds or clumps. This transfer affects the large scale flows of the diffuse plasmas as well as the evolution of the clumps. I review our current understanding of mass-injection processes, and examine intermediate-scale structure and the global effect of mass-loading on a flow. I then discuss mass-loading in a variety of diffuse sources.

J. M. Pittard

2006-07-13T23:59:59.000Z

302

On the Photon Mass  

E-Print Network (OSTI)

We review the case for the photon having a tiny mass compatible with the experimental limits. We go over some possible experimental tests for such a photon mass including the violation of Lorentz symmetry. We point out that such violations may already have been witnessed in tests involving high energy gamma rays from outer space as also ultra high energy cosmic rays.

Burra G. Sidharth

2007-06-22T23:59:59.000Z

303

Thermal masses in leptogenesis  

E-Print Network (OSTI)

We investigate the validity of using thermal masses in the kinematics of final states in the decay rate of heavy neutrinos in leptogenesis calculations. We find that using thermal masses this way is a reasonable approximation, but corrections arise through quantum statistical distribution functions and leptonic quasiparticles.

Kiessig, Clemens P

2009-01-01T23:59:59.000Z

304

Elbow mass flow meter  

DOE Patents (OSTI)

The present invention includes a combination of an elbow pressure drop generator and a shunt-type mass flow sensor for providing an output which gives the mass flow rate of a gas that is nearly independent of the density of the gas. For air, the output is also approximately independent of humidity. 3 figs.

McFarland, A.R.; Rodgers, J.C.; Ortiz, C.A.; Nelson, D.C.

1994-08-16T23:59:59.000Z

305

The origin of mass  

Science Conference Proceedings (OSTI)

The origin of mass is one of the deepest mysteries in science. Neutrons and protons, which account for almost all visible mass in the Universe, emerged from a primordial plasma through a cataclysmic phase transition microseconds after the Big Bang. However, ... Keywords: Gordon Bell Prize categories: scalability and time to solution, SC13 proceedings

Peter Boyle, Michael I. Buchoff, Norman Christ, Taku Izubuchi, Chulwoo Jung, Thomas C. Luu, Robert Mawhinney, Chris Schroeder, Ron Soltz, Pavlos Vranas, Joseph Wasem

2013-11-01T23:59:59.000Z

306

ARM - Evaluation Product - Multispectral Thermal Imager (MTI)  

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

ProductsMultispectral Thermal Imager (MTI) ProductsMultispectral Thermal Imager (MTI) Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Evaluation Product : Multispectral Thermal Imager (MTI) 2000.10.01 - 2003.05.02 Site(s) NSA SGP General Description The Multispectral Thermal Imager is a space-based research and development project sponsored by the U.S. Department of Energy (DOE), Office of Nonproliferation and National Security. MTI's primary objective is to demonstrate advanced multispectral and thermal imaging, image processing, and associated technologies that could be used in future systems for detecting and characterizing facilities producing weapons of mass destruction. However, ARM and the MTI have an arrangement that allows ARM to receive MTI images.

307

W Transverse Mass  

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

Some Data Analysis Some Data Analysis The Tevatron produces millions of collisions each second in CDF and DZero. The detectors have hardware triggers to decide if a collision is "interesting," that is it contains a candidate event for any one of a number studies. Our dataset contains 48,844 candidate events for a W mass study. There are other datasets to study Z mass, top and b quarks, QCD, etc. Why don't all the W decays give exactly the same mass? Are all these candidates really Ws? What if we chose only some of these data. How would our choice effect the value of the transverse mass? Work with your classmates. Test the data to see what you can learn. Help with data analysis. Record the best estimate of the W transverse mass from your data analysis. Explain which data you used and why. Check with your classmates and explain any differences between your estimate and theirs.

308

NIST Image Gallery: Image Details  

Science Conference Proceedings (OSTI)

... from the bright glare in the distance transmit images of a cat-like face at ... Though false color has been added to the cats faces, they are otherwise ...

309

NIST Image Gallery: Image Details  

Science Conference Proceedings (OSTI)

... a href http://www.nist.gov/public_affairs/images/Nanopore 20device.avi See video /a PHY, DARPA, spectroscopy See also http://www.nist.gov/pml ...

310

MassMass transfer andtransfer and arationstearationste  

E-Print Network (OSTI)

, temperature, T, and energy, E, are scalars and their gradient is a vector dc/dx or arationste scalars diffusion coefficient D; for species A in medium B : D = DAB 4 erföringo dx dc D dt.A dm m Massöve c cSepa dx dc )DD(m th Irreversible Thermodynamics considers Thermo-diffusion 4 erföringo T T Thermo

Zevenhoven, Ron

311

Ion-mobility Spectrometry Based NOx Sensor - Nuclear Engineering Division  

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

NPNS > Sensors and NPNS > Sensors and Instrumentation and NDE > Energy System Application > DOE Office of Transportation Technologies > Ion-mobility Spectrometry Based NOx Sensor Capabilities Sensors and Instrumentation and Nondestructive Evaluation Overview Energy System Applications Overview DOE Office of Fossil Energy DOE Office of Transportation Technologies Ion-mobility Spectrometry Based NOx Sensor DOE Office of Power Technology Work for Others Safety-Related Applications Homeland Security Applications Biomedical Applications Millimiter Wave Group Papers Other NPNS Capabilities Work with Argonne Contact us For Employees Site Map Help Join us on Facebook Follow us on Twitter NE on Flickr Sensors and Instrumentation and Nondestructive Evaluation Ion-mobility Spectrometry Based NOx Sensor

312

Method of trivalent chromium concentration determination by atomic spectrometry  

DOE Patents (OSTI)

A method is disclosed for determining the concentration of trivalent chromium Cr(III) in a sample. The addition of perchloric acid has been found to increase the atomic chromium spectrometric signal due to Cr(III), while leaving the signal due to hexavalent chromium Cr(VI) unchanged. This enables determination of the Cr(III) concentration without pre-concentration or pre-separation from chromium of other valences. The Cr(III) concentration may be measured using atomic absorption spectrometry, atomic emission spectrometry or atomic fluorescence spectrometry.

Reheulishvili, Aleksandre N. (Tbilisi, 0183, GE); Tsibakhashvili, Neli Ya. (Tbilisi, 0101, GE)

2006-12-12T23:59:59.000Z

313

Mass Wasting in the Western Galapagos Islands  

E-Print Network (OSTI)

Oceanic island volcanoes such as those in the Hawaiian, Canary and Galapagos Islands are known to become unstable, causing failures of the subaerial and submarine slopes of the volcanic edifices. These mass wasting events appear to be the primary source of destruction and loss of volume of many oceanic islands, but our knowledge of mass wasting is still rudimentary in many seamount and island chains. To better understand mass wasting in the western Galapagos Islands, multi-beam bathymetry and backscatter sidescan sonar images were used to examine topography and acoustic backscatter signatures that are characteristic of mass wasting. Observations show that mass wasting plays an important role in the development of Galapagos volcanoes. While volcanic activity continues to conceal the submarine terrain, the data show that four forms of mass wasting are identified including debris flows, slumps sheets, chaotic slumps, and detached blocks. A total of 23 mass wasting features were found to exist in the western Galapagos Islands, including fourteen debris flows with one that incorporated a set of detached blocks, seven slump sheets, and one chaotic slump. Some of the indentified features have obvious origination zones while the sources of others are not clearly identifiable. Approximately 73 percent of the surveyed coastlines are affected by slumping on the steep upper slopes and ~64 percent are affected by debris flows on the lower slopes. Unlike the giant landslides documented by GLORIA imagery around the Hawaiian Islands, the western Galapagos Islands appear to be characterized by small slump sheets existing along the steep shallow submarine flanks of the island and by debris flows that are flanked by rift zones and extend off the platform. This study indicates that submarine mass wasting is widespread in the western Galapagos, suggesting that the production of small-scale downslope movement is part of the erosive nature of these oceanic volcanic islands.

Hall, Hillary

2011-08-01T23:59:59.000Z

314

Amplitude and phase?modulation (AM?PM) wide?band photothermal spectrometry. II. Experiment  

Science Conference Proceedings (OSTI)

Amplitude and phase?modulation (AM?PM) wide?band photothermal spectrometry is experimentally demonstrated

J. F. Power

1990-01-01T23:59:59.000Z

315

History Images  

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

History Images History Images Los Alamos History in Images Los Alamos has a proud history and heritage of almost 70 years of science and innovation. The people of the Laboratory work on advanced technologies to provide the best scientific and engineering solutions to many of the nation's most crucial security challenges. Click thumbnails to enlarge. Photos arranged by most recent first, horizontal formats before vertical. See Flickr for more sizes and details. Back in the day Back in the day LA bridge in Los Alamos LA bridge in Los Alamos 1945 Army-Navy "E" Award 1945 Army-Navy "E" Award Louis Rosen Louis Rosen Bob Van Ness Robert Kuckuck and Michael Anastasio Bob Van Ness Robert Kuckuck and Michael Anastasio TA-18 TA-18 Elmer Island TU-4 assembly area Elmer Island TU-4 assembly area

316

Higgs Mass Calculations  

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

this sheet now. Help with data analysis Higgs Mass Plot Project Contact: Thomas Jordan - jordant@fnal.gov Web Maintainer: qnet-webmaster@fnal.gov Last Update: August 22,...

317

Solids mass flow determination  

DOE Patents (OSTI)

Method and apparatus for determining the mass flow rate of solids mixed with a transport fluid to form a flowing mixture. A temperature differential is established between the solids and fluid. The temperature of the transport fluid prior to mixing, the temperature of the solids prior to mixing, and the equilibrium temperature of the mixture are monitored and correlated in a heat balance with the heat capacities of the solids and fluid to determine the solids mass flow rate.

Macko, Joseph E. (Hempfield Township, Westmoreland County, PA)

1981-01-01T23:59:59.000Z

318

High-Resolution Fast-Neutron Spectrometry for Arms Control and Treaty Verification  

Science Conference Proceedings (OSTI)

Many nondestructive nuclear analysis techniques have been developed to support the measurement needs of arms control and treaty verification, including gross photon and neutron counting, low- and high-resolution gamma spectrometry, time-correlated neutron measurements, and photon and neutron imaging. One notable measurement technique that has not been extensively studied to date for these applications is high-resolution fast-neutron spectrometry (HRFNS). Applied for arms control and treaty verification, HRFNS has the potential to serve as a complimentary measurement approach to these other techniques by providing a means to either qualitatively or quantitatively determine the composition and thickness of non-nuclear materials surrounding neutron-emitting materials. The technique uses the normally-occurring neutrons present in arms control and treaty verification objects of interest as an internal source of neutrons for performing active-interrogation transmission measurements. Most low-Z nuclei of interest for arms control and treaty verification, including 9Be, 12C, 14N, and 16O, possess fast-neutron resonance features in their absorption cross sections in the 0.5- to 5-MeV energy range. Measuring the selective removal of source neutrons over this energy range, assuming for example a fission-spectrum starting distribution, may be used to estimate the stoichiometric composition of intervening materials between the neutron source and detector. At a simpler level, determination of the emitted fast-neutron spectrum may be used for fingerprinting 'known' assemblies for later use in template-matching tests. As with photon spectrometry, automated analysis of fast-neutron spectra may be performed to support decision making and reporting systems protected behind information barriers. This paper will report recent work at Idaho National Laboratory to explore the feasibility of using HRFNS for arms control and treaty verification applications, including simulations and experiments, using fission-spectrum neutron sources to assess neutron transmission through composite low-Z attenuators.

David L. Chichester; James T. Johnson; Edward H. Seabury

2012-07-01T23:59:59.000Z

319

W Transverse Mass  

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

Transverse Mass Histogram Transverse Mass Histogram Data for 49,844 candidate W events are in an Excel spreadsheet with the following data as shown in the table below: A B C D 1 Run No Event No W TMass GeV/c2 Bins 2 55237 19588 68.71732 3 55237 30799 72.19464 Get the data. Sort the data by ascending mass. Be sure to sort all the data in the first three columns! Make a histogram of the data. Rather than graphing the data as individual points, physicists group the data by mass. They consider the full range of the data and divide it into "bins" of equal range size. A histogram is a graph of the number of events in each bin vs. the bin range. They are looking for a peak in the data where most of the masses fall. This will be the value of the mass as detemined by that dataset, and the width of the distribution is a reflection of the errors in the measurements.

320

A backscattering spectrometry device for identifying unknown elements present in a workpiece  

DOE Patents (OSTI)

This invention is comprised of a backscattering spectrometry method and device for identifying and quantifying impurities in a workpiece during processing and manufacturing of that workpiece. While the workpiece is implanted with an ion beam, that same ion beam backscatters resulting from collisions with known atoms and with impurities within the workpiece. Those ions backscatter along a predetermined scattering angle and are filtered using a self-supporting filter to stop the ions with a lower energy because they collided with the known atoms of the workpiece of a smaller mass. Those ions which pass through the filter have a greater energy resulting from impact with impurities having a greater mass than the known atoms of the workpiece. A detector counts the number and measures the energy of the ions which pass through the filter. From the energy determination and knowledge of the scattering angle, a mass calculation determines the identity, and from the number and solid angle of the scattering angle, a relative concentration of the impurity is obtained.

Doyle, B.L.; Knapp, J.A.

1990-12-31T23:59:59.000Z

Note: This page contains sample records for the topic "imaging 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

SUBSTELLAR-MASS CONDENSATIONS IN PRESTELLAR CORES  

SciTech Connect

We present combined Submillimeter Array and single-dish images of the (sub)millimeter dust continuum emission toward two prestellar cores, SM1 and B2-N5, in the nearest star-cluster-forming region, {rho} Ophiuchus. Our combined images indicate that SM1 and B2-N5 consist of three and four condensations, respectively, with masses of 10{sup -2}-10{sup -1} M{sub Sun} and sizes of a few hundred AU. The individual condensations have mean densities of 10{sup 8}-10{sup 9} cm{sup -3} and the masses are comparable to or larger than the critical Bonner-Ebert mass, indicating that self-gravity plays an important role in the dynamical evolution of the condensations. The coalescence timescale of these condensations is estimated to be about 10{sup 4} yr, which is comparable to the local gravitational collapse timescale, suggesting that merging of the condensations, instead of accretion, plays an essential role in the star formation process. These results challenge the standard theory of star formation, where a single, rather featureless, prestellar core collapses to form at most a couple of condensations, each of which potentially evolves into a protostar that is surrounded by a rotating disk where planets are created.

Nakamura, Fumitaka; Kawabe, Ryohei [National Astronomical Observatory, Mitaka, Tokyo 181-8588 (Japan); Takakuwa, Shigehisa, E-mail: fumitaka.nakamura@nao.ac.jp [Academia Sinica Institute of Astronomy and Astrophysics, P.O. Box 23-141, Taipei 106, Taiwan (China)

2012-10-20T23:59:59.000Z

322

Imaging bolometer  

DOE Patents (OSTI)

Radiation-hard, steady-state imaging bolometer. A bolometer employing infrared (IR) imaging of a segmented-matrix absorber of plasma radiation in a cooled-pinhole camera geometry is described. The bolometer design parameters are determined by modeling the temperature of the foils from which the absorbing matrix is fabricated by using a two-dimensional time-dependent solution of the heat conduction equation. The resulting design will give a steady-state bolometry capability, with approximately 100 Hz time resolution, while simultaneously providing hundreds of channels of spatial information. No wiring harnesses will be required, as the temperature-rise data will be measured via an IR camera. The resulting spatial data may be used to tomographically investigate the profile of plasmas.

Wurden, Glen A. (Los Alamos, NM)

1999-01-01T23:59:59.000Z

323

Imaging bolometer  

DOE Patents (OSTI)

Radiation-hard, steady-state imaging bolometer is disclosed. A bolometer employing infrared (IR) imaging of a segmented-matrix absorber of plasma radiation in a cooled-pinhole camera geometry is described. The bolometer design parameters are determined by modeling the temperature of the foils from which the absorbing matrix is fabricated by using a two-dimensional time-dependent solution of the heat conduction equation. The resulting design will give a steady-state bolometry capability, with approximately 100 Hz time resolution, while simultaneously providing hundreds of channels of spatial information. No wiring harnesses will be required, as the temperature-rise data will be measured via an IR camera. The resulting spatial data may be used to tomographically investigate the profile of plasmas. 2 figs.

Wurden, G.A.

1999-01-19T23:59:59.000Z

324

Weak Lensing Mass Reconstruction of the Galaxy Cluster Abell 209  

E-Print Network (OSTI)

Weak lensing applied to deep optical images of clusters of galaxies provides a powerful tool to reconstruct the distribution of the gravitating mass associated to these structures. We use the shear signal extracted by an analysis of deep exposures of a region centered around the galaxy cluster Abell 209, at redshift z=0.2, to derive both a map of the projected mass distribution and an estimate of the total mass within a characteristic radius. We use a series of deep archival R-band images from CFHT-12k, covering an area of 0.3 deg^2. We determine the shear of background galaxy images using a new implementation of the modified Kaiser-Squires-Broadhurst pipeline for shear determination, which we has been tested against the ``Shear TEsting Program 1 and 2'' simulations. We use mass aperture statistics to produce maps of the 2 dimensional density distribution, and parametric fits using both Navarro-Frenk-White (NFW) and singular-isothermal-sphere profiles to constrain the total mass. The projected mass distribution shows a pronounced asymmetry, with an elongated structure extending from the SE to the NW. This is in general agreement with the optical distribution previously found by other authors. A similar elongation was previously detected in the X-ray emission map, and in the distribution of galaxy colours. The circular NFW mass profile fit gives a total mass of M_{200} = 7.7^{+4.3}_{-2.7} 10^{14} solar masses inside the virial radius r_{200} = 1.8\\pm 0.3 Mpc. The weak lensing profile reinforces the evidence for an elongated structure of Abell 209, as previously suggested by studies of the galaxy distribution and velocities.

S. Paulin-Henriksson; V. Antonuccio-Delogu; C. P. Haines; M. Radovich; A. Mercurio; U. Becciani

2007-01-28T23:59:59.000Z

325

Isotopic Effect on Ion Mobility and Separation of Isotopomers by High-Field Ion Mobility Spectrometry  

SciTech Connect

Since early 1900-s, when vacuum techniques and ion detectors first enabled investigations of gas-phase ions, two approaches to their separation and characterization have emerged - mass spectrometry (MS) and ion mobility spectrometry (IMS).1,2 Though both exploit that distinct charged species move in electric fields differently, MS is performed in vacuum and is based only on the ion mass/charge (m/q) ratio while IMS involves sufficiently dense buffer gases and relies on ion transport properties. The first major discovery enabled by MS was the existence of isotopes by Thomson and Aston,3 and isotopic analyses have since been integral to MS. In particular, the preparative separation of U isotopes using Lawrence’s Calutron was the first industrial application of MS,4 and isotopic labeling is key to MS quantification methods. With IMS, the issue of isotopes was largely ignored as the resolving power (R) was generally too low for their separation. Here, we demonstrate that recently developed high-resolution differential IMS can separate isotopic molecular ions, including nominal isobars with different isotopic content and isotopomers. This capability may enable a new method for isotope separation in a small-scale format at ambient pressure and aid localization of labeled sites in various molecules. Perhaps most importantly, the isotopic shifts depend on the labeled atom position and thus may contain the kind of detailed structural information that is available in solution or solid state using tools such as NMR but has not generally been obtainable for gas-phase ions.

Shvartsburg, Alexandre A.; Clemmer, David E.; Smith, Richard D.

2010-10-01T23:59:59.000Z

326

Photon: history, mass, charge  

E-Print Network (OSTI)

The talk consists of three parts. ``History'' briefly describes the emergence and evolution of the concept of photon during the first two decades of the 20th century. ``Mass'' gives a short review of the literature on the upper limit of the photon's mass. ``Charge'' is a critical discussion of the existing interpretation of searches for photon charge. Schemes, in which all photons are charged, are grossly inconsistent. A model with three kinds of photons (positive, negative and neutral) seems at first sight to be more consistent, but turns out to have its own serious problems.

L. B. Okun

2006-02-03T23:59:59.000Z

327

Mass and Heat Recovery  

E-Print Network (OSTI)

In the last few years heat recovery was under spot and in air conditioning fields usually we use heat recovery by different types of heat exchangers. The heat exchanging between the exhaust air from the building with the fresh air to the building (air to air heat exchanger). In my papers I use (water to air heat exchanger) as a heat recovery and I use the water as a mass recovery. The source of mass and heat recovery is the condensate water which we were dispose and connect it to the drain lines.

Hindawai, S. M.

2010-01-01T23:59:59.000Z

328

Ion exchange separation and mass spectrometric analysis of uranium for solutions containing plutonium  

SciTech Connect

An ion exchange technique separates plutonium from uranium using Dowex-1 resin and a methanol--HCl plutonium elutriant. The method is applicable to both trace uranium determination and uranium isotopic distribution analysis by mass spectrometry. Distribution coefficients for plutonium, and elution curves for uranium and plutonium are shown. For uranium analysis the percent relative standard deviation is 0.8 at 120-2400 micrograms uranium per gram plutonium and 5.0 at 5 micrograms uranium per gram plutonium. (auth)

McBride, K.C.

1975-06-01T23:59:59.000Z

329

Visualization of High Resolution Spatial Mass Spectrometric Data during Acquisition  

Science Conference Proceedings (OSTI)

Mass Spectrometric Imaging (IMS) allows the generation of 2D ion density maps that help visualize molecules present in sections of tissues and cells. The combination of spatial and mass resolution results in large and complex data sets that require powerful and efficient analysis and interpretation. In this paper, a graphical user interface (GUI) that can visualize the large data during data acquisition itself is presented. The program also has the ability to perform processing and analysis of the dataset. The various functions of the GUI including visualization of mass spectra, generation of 2D maps for selected species, manipulation of the heat maps, and peak identification are also presented.

Thomas, Mathew; Heath, Brandi S.; Laskin, Julia; Li, Dongsheng; Liu, Ellen C.; Hui, Katrina L.; Kuprat, Andrew P.; Kleese van Dam, Kerstin; Carson, James P.

2012-08-28T23:59:59.000Z

330

Warm Water Mass Formation  

Science Conference Proceedings (OSTI)

Poleward heat transport by the own implies warm Water mass formation, i.e., the retention by the tropical and subtropical ocean of some of its net radiant heat gain. Under what condition net heat retention becomes comparable to latent heat ...

G. T. Csanady

1984-02-01T23:59:59.000Z

331

Method for calibrating mass spectrometers  

DOE Patents (OSTI)

A method whereby a mass spectra generated by a mass spectrometer is calibrated by shifting the parameters used by the spectrometer to assign masses to the spectra in a manner which reconciles the signal of ions within the spectra having equal mass but differing charge states, or by reconciling ions having known differences in mass to relative values consistent with those known differences. In this manner, the mass spectrometer is calibrated without the need for standards while allowing the generation of a highly accurate mass spectra by the instrument.

Anderson, Gordon A [Benton City, WA; Brands, Michael D [Richland, WA; Bruce, James E [Schwenksville, PA; Pasa-Tolic, Ljiljana [Richland, WA; Smith, Richard D [Richland, WA

2002-12-24T23:59:59.000Z

332

Twisted mass finite volume effects  

SciTech Connect

We calculate finite-volume effects on the pion masses and decay constant in twisted mass lattice QCD at finite lattice spacing. We show that the lighter neutral pion in twisted mass lattice QCD gives rise to finite-volume effects that are exponentially enhanced when compared to those arising from the heavier charged pions. We demonstrate that the recent two flavor twisted mass lattice data can be better fitted when twisted mass effects in finite-volume corrections are taken into account.

Colangelo, Gilberto; Wenger, Urs; Wu, Jackson M. S. [Albert Einstein Center for Fundamental Physics, Institute for Theoretical Physics, University of Bern, Sidlerstrasse 5, 3012 Bern (Switzerland)

2010-08-01T23:59:59.000Z

333

Sandia National Labs: PCNSC: Heavy Ion Backscattering Spectrometry  

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

Heavy Ion Backscattering Spectrometry (HIBS) Heavy Ion Backscattering Spectrometry (HIBS) IBA Table (HTML) | IBA Table (135KB GIF) | IBA Table (1.2MB PDF) | IBA Table (33MB TIF) | Heavy Ion Backscattering Spectrometry (HIBS) | Virtual Lab Tour (6MB) Description of Technique: HIBS is used to detect ultra-trace levels of heavy impurities on the surface of a Si wafer. HIBS has advantages over TXRF, including: Improved sensitivity for most elements Quantifying composition without standards Measurement on rough surfaces. HIBS is accomplished by focusing a 120 keV beam of C+ions onto a small spot at the wafer's surface. The backscattered ions are collected by a time-of-flight (TOF) detector array with a large solid angle. The flight time of the backscattered C identifies the near-surface impurities and the

334

Mass Market Demand Response  

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

Mass Market Demand Response Mass Market Demand Response Speaker(s): Karen Herter Date: July 24, 2002 - 12:00pm Location: Bldg. 90 Demand response programs are often quickly and poorly crafted in reaction to an energy crisis and disappear once the crisis subsides, ensuring that the electricity system will be unprepared when the next crisis hits. In this paper, we propose to eliminate the event-driven nature of demand response programs by considering demand responsiveness a component of the utility obligation to serve. As such, demand response can be required as a condition of service, and the offering of demand response rates becomes a requirement of utilities as an element of customer service. Using this foundation, we explore the costs and benefits of a smart thermostat-based demand response system capable of two types of programs: (1) a mandatory,

335

Compositional characterization and imaging of "Wall-bound" acylesters of Populus trichocarpa Reveal Differential Accumulation of acyl Molecules in Normal and Reactive Woods  

SciTech Connect

Acylesterification is one of the common modifications of cell wall non-cellulosic polysaccharides and/or lignin primarily in monocot plants. We analyzed the cell-wall acylesters of black cottonwood (Populus trichocarpa Torr. & Gray) with liquid chromatography-mass spectrometry (LC-MS), Fourier transform-infrared (FT-IR) microspectroscopy, and synchrotron infrared (IR) imaging facility. The results revealed that the cell wall of dicotyledonous poplar, as the walls of many monocot grasses, contains a considerable amount of acylesters, primarily acetyl and p-hydroxycinnamoyl molecules. The 'wall-bound' acetate and phenolics display a distinct tissue specific-, bending stress responsible- and developmental-accumulation pattern. The 'wall-bound' p-coumarate predominantly accumulated in young leaves and decreased in mature leaves, whereas acetate and ferulate mostly amassed in the cell wall of stems. Along the development of stem, the level of the 'wall-bound' ferulate gradually increased, while the basal level of p-coumarate further decreased. Induction of tension wood decreased the accumulation of the 'wall-bound' phenolics while the level of acetate remained constant. Synchrotron IR-mediated chemical compositional imaging revealed a close spatial distribution of acylesters with cell wall polysaccharides in poplar stem. These results indicate that different 'wall-bound' acylesters play distinct roles in poplar cell wall structural construction and/or metabolism of cell wall matrix components.

Guo, J.; Park, S; Yu, X; Liu, C

2008-01-01T23:59:59.000Z

336

FM DANTE fast imaging and variations: emerging rf-based ultrafast imaging techniques  

Science Conference Proceedings (OSTI)

Keywords: DANTE fast imaging, NMR, burst imaging, fast chemical shift imaging, fast imaging, fast spectroscopic imaging, fast susceptibility imaging

Z. H. Cho; Y. M. Ro; I. K. Hong

1998-01-01T23:59:59.000Z

337

Strange and charm meson masses from twisted mass lattice QCD  

E-Print Network (OSTI)

We present first results of a 2+1+1 flavor twisted mass lattice QCD computation of strange and charm meson masses. We focus on D and D_s mesons with spin J = 0,1 and parity P = -,+.

Martin Kalinowski; Marc Wagner

2012-12-03T23:59:59.000Z

338

MassMass transfer andtransfer and separation technologyseparation technology  

E-Print Network (OSTI)

Driving force Apparatus Heat exchange Energy T Heat exchanger Gas absorption Mass G L c y-y* Packed towerGas absorption Mass G L c, y-y* Packed tower, or tray column Gas desorption Mass L G c, y*-y Packed tower tower, or tray column and B from a mix Vaporisation cooling Energy, water h (enthalpy) Spray tower

Zevenhoven, Ron

339

Split image optical display  

DOE Patents (OSTI)

A video image is displayed from an optical panel by splitting the image into a plurality of image components, and then projecting the image components through corresponding portions of the panel to collectively form the image. Depth of the display is correspondingly reduced.

Veligdan, James T. (Manorville, NY)

2007-05-29T23:59:59.000Z

340

"Gravitational mass" of information?  

E-Print Network (OSTI)

We hypothesize possible new types of forces that would be the result of new types of interactions, static and a slow transient, between objects with related information contents (pattern). Such mechanism could make material composition dependence claimed by Fishbach, et al in Eotvos type experiments plausible. We carried out experiments by using a high-resolution scale with the following memories: USB-2 flash drives (1-16GB), DVD and CD disks to determine if such an interaction exist/detectable with a scale resolution of 10 microgram with these test objects. We applied zero information, white noise and 1/f noise type data. Writing or deleting the information in any of these devices causes peculiar negative weight transients, up to milligrams (mass fraction around 10^-5), which is followed by various types of relaxation processes. These relaxations have significantly different dynamics compared to transients observed during cooling after stationary external heating. Interestingly, a USB-1 MP3 player has also developed comparable transient mass loss during playing music. A classical interpretation of the negative weight transients could be absorbed water in hygroscopic components however comparison of relaxation time constants with air humidity data does not support an obvious explanation. Another classical interpretation with certain contribution is the lifting Bernoulli force caused by the circulation due to convection of the warm air. However, in this case all observed time constants with a device should have been the same unless some hidden parameter causes the observed variations. Further studies are warranted to clarify if there is indeed a new force, which is showing up as negative mass at weight measurement when high-density structural information is changed or read out (measured).

Laszlo B. Kish

2007-11-08T23:59:59.000Z

Note: This page contains sample records for the topic "imaging 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

MASS SPECTROMETER LEAK  

DOE Patents (OSTI)

An improved valve is described for precisely regulating the flow of a sample fluid to be analyzed, such as in a mass spectrometer, where a gas sample is allowed to "leak" into an evacuated region at a very low, controlled rate. The flow regulating valve controls minute flow of gases by allowing the gas to diffuse between two mating surfaces. The structure of the valve is such as to prevent the corrosive feed gas from contacting the bellows which is employed in the operation of the valve, thus preventing deterioration of the bellows.

Shields, W.R.

1960-10-18T23:59:59.000Z

342

HIGEE Mass Transfer  

E-Print Network (OSTI)

Distillation, absorption, and gas stripping have traditionally been performed in tall columns utilizing trays or packing. Columns perform satisfactorily, but have characteristics which may be disadvantages in some applications: Large size, particularly height; high weight; high cost of installation; difficulty in modularization; foaming for certain systems; must be vertical, especially for trayed towers; large liquid inventory; difficulty in modifying column internals once installed; start up time to reach steady state conditions in excessive. Many of these disadvantages can be overcome by use of HIGEE, an innovative vapor-liquid mass transfer system which utilizes a rotating bed of packing to achieve high efficiency separations, and consequent reduction in size and weight.

Mohr, R. J.; Fowler, R.

1986-06-01T23:59:59.000Z

343

Heat and mass exchanger  

Science Conference Proceedings (OSTI)

A mass and heat exchanger includes at least one first substrate with a surface for supporting a continuous flow of a liquid thereon that either absorbs, desorbs, evaporates or condenses one or more gaseous species from or to a surrounding gas; and at least one second substrate operatively associated with the first substrate. The second substrate includes a surface for supporting the continuous flow of the liquid thereon and is adapted to carry a heat exchange fluid therethrough, wherein heat transfer occurs between the liquid and the heat exchange fluid.

Lowenstein, Andrew (Princeton, NJ); Sibilia, Marc J. (Princeton, NJ); Miller, Jeffrey A. (Hopewell, NJ); Tonon, Thomas (Princeton, NJ)

2011-06-28T23:59:59.000Z

344

Determining the neutrino mass hierarchy  

Science Conference Proceedings (OSTI)

In this proceedings I review the physics that future experiments will use to determine the neutrino mass hierarchy.

Parke, Stephen J.; /Fermilab

2006-07-01T23:59:59.000Z

345

Mass Transport within Soils  

Science Conference Proceedings (OSTI)

Contaminants in soil can impact human health and the environment through a complex web of interactions. Soils exist where the atmosphere, hydrosphere, geosphere, and biosphere converge. Soil is the thin outer zone of the earth's crust that supports rooted plants and is the product of climate and living organisms acting on rock. A true soil is a mixture of air, water, mineral, and organic components. The relative proportions of these components determine the value of the soil for agricultural and for other human uses. These proportions also determine, to a large extent, how a substance added to soil is transported and/or transformed within the soil (Spositio, 2004). In mass-balance models, soil compartments play a major role, functioning both as reservoirs and as the principal media for transport among air, vegetation, surface water, deeper soil, and ground water (Mackay, 2001). Quantifying the mass transport of chemicals within soil and between soil and atmosphere is important for understanding the role soil plays in controlling fate, transport, and exposure to multimedia pollutants. Soils are characteristically heterogeneous. A trench dug into soil typically reveals several horizontal layers having different colors and textures. As illustrated in Figure 1, these multiple layers are often divided into three major horizons: (1) the A horizon, which encompasses the root zone and contains a high concentration of organic matter; (2) the B horizon, which is unsaturated, lies below the roots of most plants, and contains a much lower organic carbon content; and (3) the C horizon, which is the unsaturated zone of weathered parent rock consisting of bedrock, alluvial material, glacial material, and/or soil of an earlier geological period. Below these three horizons lies the saturated zone - a zone that encompasses the area below ground surface in which all interconnected openings within the geologic media are completely filled with water. Similarly to the unsaturated zone with three major horizons, the saturated zone can be further divided into other zones based on hydraulic and geologic conditions. Wetland soils are a special and important class in which near-saturation conditions exist most of the time. When a contaminant is added to or formed in a soil column, there are several mechanisms by which it can be dispersed, transported out of the soil column to other parts of the environment, destroyed, or transformed into some other species. Thus, to evaluate or manage any contaminant introduced to the soil column, one must determine whether and how that substance will (1) remain or accumulate within the soil column, (2) be transported by dispersion or advection within the soil column, (3) be physically, chemically, or biologically transformed within the soil (i.e., by hydrolysis, oxidation, etc.), or (4) be transported out of the soil column to another part of the environment through a cross-media transfer (i.e., volatilization, runoff, ground water infiltration, etc.). These competing processes impact the fate of physical, chemical, or biological contaminants found in soils. In order to capture these mechanisms in mass transfer models, we must develop mass-transfer coefficients (MTCs) specific to soil layers. That is the goal of this chapter. The reader is referred to other chapters in this Handbook that address related transport processes, namely Chapter 13 on bioturbation, Chapter 15 on transport in near-surface geological formations, and Chapter 17 on soil resuspention. This chapter addresses the following issues: the nature of soil pollution, composition of soil, transport processes and transport parameters in soil, transformation processes in soil, mass-balance models, and MTCs in soils. We show that to address vertical heterogeneity in soils in is necessary to define a characteristic scaling depth and use this to establish process-based expressions for soil MTCs. The scaling depth in soil and the corresponding MTCs depend strongly on (1) the composition of the soil and physical state of the soil, (2) the chemical and physic

McKone, Thomas E.

2009-03-01T23:59:59.000Z

346

Safeguards Verification Measurements using Laser Ablation, Absorbance Ratio Spectrometry in Gaseous Centrifuge Enrichment Plants  

Science Conference Proceedings (OSTI)

Laser Ablation Absorbance Ratio Spectrometry (LAARS) is a new verification measurement technology under development at the US Department of Energy’s (DOE) Pacific Northwest National Laboratory (PNNL). LAARS uses three lasers to ablate and then measure the relative isotopic abundance of uranium compounds. An ablation laser is tightly focused on uranium-bearing solids producing a small plume containing uranium atoms. Two collinear wavelength-tuned spectrometry lasers transit through the plume and the absorbance of U-235 and U-238 isotopes are measured to determine U-235 enrichment. The measurement has high relative precision and detection limits approaching the femtogram range for uranium. It is independent of chemical form and degree of dilution with nuisance dust and other materials. High speed sample scanning and pinpoint characterization allow measurements on millions of particles/hour to detect and analyze the enrichment of trace uranium in samples. The spectrometer is assembled using commercially available components at comparatively low cost, and features a compact and low power design. Future designs can be engineered for reliable, autonomous deployment within an industrial plant environment. Two specific applications of the spectrometer are under development: 1) automated unattended aerosol sampling and analysis and 2) on-site small sample destructive assay measurement. The two applications propose game-changing technological advances in gaseous centrifuge enrichment plant (GCEP) safeguards verification. The aerosol measurement instrument, LAARS-environmental sampling (ES), collects aerosol particles from the plant environment in a purpose-built rotating drum impactor and then uses LAARS-ES to quickly scan the surface of the impactor to measure the enrichments of the captured particles. The current approach to plant misuse detection involves swipe sampling and offsite analysis. Though this approach is very robust it generally requires several months to obtain results from a given sample collection. The destructive assay instrument, LAARS-destructive assay (DA), uses a simple purpose-built fixture with a sampling planchet to collect adsorbed UF6 gas from a cylinder valve or from a process line tap or pigtail. A portable LAARS-DA instrument scans the microgram quantity of uranium collected on the planchet and the assay of the uranium is measured to ~0.15% relative precision. Currently, destructive assay samples for bias defect measurements are collected in small sample cylinders for offsite mass spectrometry measurement.

Anheier, Norman C.; Cannon, Bret D.; Qiao, Hong (Amy); Phillips, Jon R.

2012-07-01T23:59:59.000Z

347

No evidence for mass segregation in young clusters  

E-Print Network (OSTI)

Aims. We investigate the validity of mass segregation indicators commonly used in the analysis of young stellar clusters. Methods. We simulate observations by constructing synthetic seeing limited images of a 1000 massive clusters (10^4 Msun) with a standard IMF and a King density distribution function. Results. We find that commonly used indicators are highly sensitive to sample incompleteness in observational data, and that radial completeness determinations do not provide satisfactory corrections, rendering the studies of radial properties highly uncertain. On the other hand, we find that under certain conditions, the global completeness can be estimated accurately, allowing for the correction of the global luminosity and mass functions of the cluster. Conclusions. We argue that there is currently no observational evidence for mass segregation in young compact clusters since there is not a robust way to differentiate between true mass segregation and sample incompleteness effects. Caution should then be ex...

Ascenso, J; Lago, M T V T

2008-01-01T23:59:59.000Z

348

Forensic Science  

Science Conference Proceedings (OSTI)

... Electrospray mass spectrometry when used with spectral libraries has been ... methods to improve the legibility of digital images such ... SPIE-Int. Soc. ...

2005-06-15T23:59:59.000Z

349

Multicolor Underwater Imaging Techniques.  

E-Print Network (OSTI)

??Studies were conducted on multispectral polarimetric subtraction imaging techniques for underwater imaging that use a broadband light source. The main objective of this study was… (more)

Waggoner, Douglas Scott

2007-01-01T23:59:59.000Z

350

Baryon Mass Extrapolation  

E-Print Network (OSTI)

Consideration of the analytical properties of pion-induced baryon self-energies leads to new functional forms for the extrapolation of light baryon masses. These functional forms reproduce the leading non-analytic behavior of chiral perturbation theory, the correct heavy-quark limit and have the advantage of containing information on the extended structure of hadrons. The forms involve only three unknown parameters which may be optimized by fitting to present lattice data. Recent dynamical fermion results from CP-PACS and UK-QCD are extrapolated using these new functional forms. We also use these functions to probe the limit of the chiral perturbative regime and shed light on the applicability of chiral perturbation theory to the extrapolation of present lattice QCD results.

Derek B. Leinweber; Anthony W. Thomas; Kazuo Tsushima; Stewart V. Wright

1999-09-14T23:59:59.000Z

351

Mass spectrometric studies of laser damage in calcium fluoride  

Science Conference Proceedings (OSTI)

Both electron impact- and laser-ionization-mass spectrometry have been used to prove the material spalled from CaF/sub 2/ surfaces by the fundamental (1.06..mu..) and harmonic (355 nm and 266 nm) outputs from a Q-switched Nd:YAG laser. We have identified a number of gas phase products, including Ca, CaF and tentatively, CaF/sub 2/, and have measured their translational and internal energy distributions. Results suggest that while the 1.06..mu.. experiments can be adequately modeled in terms of a single damage mechanism (likely avalanche breakdown), the short-wavelength results suggest the onset of second mechanism, perhaps multiphoton absorption. This is consistent with both the observed bimodal velocity distribution following short-wavelength damage, and with the decrease in CaF vibrational and rotational excitation.

Nogar, N.S.; Apel, E.C.; Estler, R.C.

1986-01-01T23:59:59.000Z

352

ON THE MASS DISTRIBUTION AND BIRTH MASSES OF NEUTRON STARS  

Science Conference Proceedings (OSTI)

We investigate the distribution of neutron star masses in different populations of binaries, employing Bayesian statistical techniques. In particular, we explore the differences in neutron star masses between sources that have experienced distinct evolutionary paths and accretion episodes. We find that the distribution of neutron star masses in non-recycled eclipsing high-mass binaries as well as of slow pulsars, which are all believed to be near their birth masses, has a mean of 1.28 M{sub Sun} and a dispersion of 0.24 M{sub Sun }. These values are consistent with expectations for neutron star formation in core-collapse supernovae. On the other hand, double neutron stars, which are also believed to be near their birth masses, have a much narrower mass distribution, peaking at 1.33 M{sub Sun }, but with a dispersion of only 0.05 M{sub Sun }. Such a small dispersion cannot easily be understood and perhaps points to a particular and rare formation channel. The mass distribution of neutron stars that have been recycled has a mean of 1.48 M{sub Sun} and a dispersion of 0.2 M{sub Sun }, consistent with the expectation that they have experienced extended mass accretion episodes. The fact that only a very small fraction of recycled neutron stars in the inferred distribution have masses that exceed {approx}2 M{sub Sun} suggests that only a few of these neutron stars cross the mass threshold to form low-mass black holes.

Oezel, Feryal; Psaltis, Dimitrios; Santos Villarreal, Antonio [Department of Astronomy, University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721 (United States); Narayan, Ramesh [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138,USA (United States)

2012-09-20T23:59:59.000Z

353

Mining partially annotated images  

Science Conference Proceedings (OSTI)

In this paper, we study the problem of mining partially annotated images. We first define what the problem of mining partially annotated images is, and argue that in many real-world applications annotated images are typically partially annotated and ... Keywords: image annotation completion and prediction, partially annotated training set, semi-supervised learning

Zhongang Qi; Ming Yang; Zhongfei (Mark) Zhang; Zhengyou Zhang

2011-08-01T23:59:59.000Z

354

Seismic Imaging and Monitoring  

SciTech Connect

I give an overview of LANL's capability in seismic imaging and monitoring. I present some seismic imaging and monitoring results, including imaging of complex structures, subsalt imaging of Gulf of Mexico, fault/fracture zone imaging for geothermal exploration at the Jemez pueblo, time-lapse imaging of a walkway vertical seismic profiling data for monitoring CO{sub 2} inject at SACROC, and microseismic event locations for monitoring CO{sub 2} injection at Aneth. These examples demonstrate LANL's high-resolution and high-fidelity seismic imaging and monitoring capabilities.

Huang, Lianjie [Los Alamos National Laboratory

2012-07-09T23:59:59.000Z

355

Seismic Imaging and Monitoring  

SciTech Connect

I give an overview of LANL's capability in seismic imaging and monitoring. I present some seismic imaging and monitoring results, including imaging of complex structures, subsalt imaging of Gulf of Mexico, fault/fracture zone imaging for geothermal exploration at the Jemez pueblo, time-lapse imaging of a walkway vertical seismic profiling data for monitoring CO{sub 2} inject at SACROC, and microseismic event locations for monitoring CO{sub 2} injection at Aneth. These examples demonstrate LANL's high-resolution and high-fidelity seismic imaging and monitoring capabilities.

Huang, Lianjie [Los Alamos National Laboratory

2012-07-09T23:59:59.000Z

356

Web accessible image similarity measurements  

Science Conference Proceedings (OSTI)

Web accessible image similarity measurements. Background: There ... messages). Web Access to Image Similarity Measurements. ...

2013-04-16T23:59:59.000Z

357

Charge Retention by Gold Clusters on Surfaces Prepared Using Soft Landing of Mass Selected Ions  

Science Conference Proceedings (OSTI)

Monodisperse gold clusters have been prepared on surfaces in different charge states through soft landing of mass-selected ions. Ligand-stabilized gold clusters were prepared in methanol solution by reduction of chloro(triphenylphosphine)gold(I) with borane tert-butylamine complex in the presence of 1,3-bis(diphenylphosphino)propane. Electrospray ionization was used to introduce the clusters into the gas-phase and mass-selection was employed to isolate a single ionic cluster species (Au11L53+, L = 1,3-bis(diphenylphosphino)propane) which was delivered to surfaces at well controlled kinetic energies. Using in-situ time of flight secondary ion mass spectrometry (TOF-SIMS) it is demonstrated that the Au11L53+ cluster retains its 3+ charge state when soft landed onto the surface of a 1H,1H,2H,2H-

Johnson, Grant E.; Priest, Thomas A.; Laskin, Julia

2012-01-24T23:59:59.000Z

358

Manhattan Project: Trinity Images  

Office of Scientific and Technical Information (OSTI)

IMAGES IMAGES Trinity Test Site (July 16, 1945) Resources > Photo Gallery The first 0.11 seconds of the Nuclear Age These seven photographs of the Trinity test were taken by time-lapse cameras. The last is 109 milliseconds, or 0.109 seconds, after detonation. Scroll down to view each individual image. The photographs are courtesy the Los Alamos National Laboratory, via the Federation of American Scientists web site. The animation is original to the Office of History and Heritage Resources. The dawn of the Nuclear Age (Trinity image #1) The dawn of the Nuclear Age Trinity image #2 Trinity image #3 Trinity image #4 Trinity image #5 Trinity, 0.09 seconds after detonation (Trinity image #6) Trinity, 0.09 seconds after detonation Trinity, 0.11 seconds after detonation (Trinity image #7)

359

Energy Functional for Nuclear Masses.  

E-Print Network (OSTI)

??An energy functional is formulated for mass calculations of nuclei across the nuclear chart with major-shell occupations as the relevant degrees of freedom. The functional… (more)

Bertolli, Michael Giovanni

2011-01-01T23:59:59.000Z

360

Proton radiography application to medical imaging  

SciTech Connect

In order to demonstrate the potential advantages of proton radiography for medical imaging, a 205 MeV proton radiography beam was developed using the Argonne National Laboratory Booster I synchrotron. Data were taken using a narrow scanning beam and an electronic detector system. The proton radiographs presented here demonstrate a significant dose reduction and improved mass resolution over conventional x-ray techniques. The radiographs also show significant differences in the proton stopping power of biological tissues and, therefore, considerable potential in soft tissue imaging. Also presented is the motivation for the interest in developing a proton tomographic scan system.

Kramer, S.L.; Moffett, D.R.; Martin, R.L.; Colton, E.P.; Steward, V.W.

1978-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "imaging 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

Static-light meson masses from twisted mass lattice QCD  

E-Print Network (OSTI)

We compute the static-light meson spectrum using two-flavor Wilson twisted mass lattice QCD. We have considered five different values for the light quark mass corresponding to 300 MeV < m_PS < 600 MeV. We have extrapolated our results, to make predictions regarding the spectrum of B and B_s mesons.

ETM Collaboration; Karl Jansen; Chris Michael; Andrea Shindler; Marc Wagner

2008-08-15T23:59:59.000Z

362

Image registration method for medical image sequences  

DOE Patents (OSTI)

Image registration of low contrast image sequences is provided. In one aspect, a desired region of an image is automatically segmented and only the desired region is registered. Active contours and adaptive thresholding of intensity or edge information may be used to segment the desired regions. A transform function is defined to register the segmented region, and sub-pixel information may be determined using one or more interpolation methods.

Gee, Timothy F.; Goddard, James S.

2013-03-26T23:59:59.000Z

363

Schottky mass measurements of heavy neutron-rich nuclides in the element range $70\\leZ \\le79$ at the ESR  

E-Print Network (OSTI)

Storage-ring mass spectrometry was applied to neutron-rich $^{197}$Au projectile fragments. Masses of $^{181,183}$Lu, $^{185,186}$Hf, $^{187,188}$Ta, $^{191}$W, and $^{192,193}$Re nuclei were measured for the first time. The uncertainty of previously known masses of $^{189,190}$W and $^{195}$Os nuclei was improved. Observed irregularities on the smooth two-neutron separation energies for Hf and W isotopes are linked to the collectivity phenomena in the corresponding nuclei.

D. Shubina; R. B. Cakirli; Yu. A. Litvinov; K. Blaum; C. Brandau; F. Bosch; J. J. Carroll; R. F. Casten; D. M. Cullen; I. J. Cullen; A. Y. Deo; B. Detwiler; C. Dimopoulou; F. Farinon; H. Geissel; E. Haettner; M. Heil; R. S. Kempley; C. Kozhuharov; R. Knöbel; J. Kurcewicz; N. Kuzminchuk; S. A. Litvinov; Z. Liu; R. Mao; C. Nociforo; F. Nolden; Z. Patyk; W. R. Plass; A. Prochazka; M. W. Reed; M. S. Sanjari; C. Scheidenberger; M. Steck; Th. Stöhlker; B. Sun; T. P. D. Swan; G. Trees; P. M. Walker; H. Weick; N. Winckler; M. Winkler; P. J. Woods; T. Yamaguchi; C. Zhou

2013-08-14T23:59:59.000Z

364

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

365

Gravity and the Fermion Mass  

E-Print Network (OSTI)

It is shown that gravity generates mass for the fermion. It does so by coupling directly with the spinor field. The coupling term is invariant with respect to the electroweak gauge group $ U(1) \\otimes SU(2)_L. $ It replaces the fermion mass term $ m\\bar{\\psi} \\psi $.

Kenneth Dalton

2004-09-08T23:59:59.000Z

366

Estimating the Amount of Coal Tar Weathering in Sediments by Two-Dimensional Automated-Sequential Gas Chromatography/Mass Spectrometry (GC-GC/MS) and Comprehensive Gas Chromatography/Mass Spectrometry (GCxGC/MS) Techniques — Phase III  

Science Conference Proceedings (OSTI)

This report is intended to inform scientists and engineers concerned with assessing and remediating former manufactured gas plants and other coal tar-contaminated sites. Although the report focuses on coal tar in sediment, the results are equally applicable to studies investigating and remediating coal tar, crude oil, and their by-products in the vadose zone or in ground or pore waters, as well as marine animals. The data provided in this report should allow more accurate analyses to better direct remedi...

2012-03-14T23:59:59.000Z

367

Standard test methods for chemical and mass spectrometric analysis of nuclear-grade gadolinium oxide (Gd2O3) powder  

E-Print Network (OSTI)

1.1 These test methods cover procedures for the chemical and mass spectrometric analysis of nuclear-grade gadolinium oxide powders to determine compliance with specifications. 1.2 The analytical procedures appear in the following order: Sections Carbon by Direct CombustionThermal Conductivity C1408 Test Method for Carbon (Total) in Uranium Oxide Powders and Pellets By Direct Combustion-Infrared Detection Method Total Chlorine and Fluorine by Pyrohydrolysis Ion Selective Electrode C1502 Test Method for Determination of Total Chlorine and Fluorine in Uranium Dioxide and Gadolinium Oxide Loss of Weight on Ignition 7-13 Sulfur by CombustionIodometric Titration Impurity Elements by a Spark-Source Mass Spectrographic C761 Test Methods for Chemical, Mass Spectrometric, Spectrochemical,Nuclear, and Radiochemical Analysis of Uranium Hexafluoride C1287 Test Method for Determination of Impurities In Uranium Dioxide By Inductively Coupled Plasma Mass Spectrometry Gadolinium Content in Gadolinium Oxid...

American Society for Testing and Materials. Philadelphia

2006-01-01T23:59:59.000Z

368

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

369

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

370

Characterization of Diesel Fuel by Chemical Separation Combined with Capillary Gas Chromatography (GC) Isotope Ratio Mass Spectrometry (IRMS)  

Science Conference Proceedings (OSTI)

The purpose of this study was to perform a preliminary investigation of compound-specific isotope analysis (CSIA) of diesel fuels to evaluate whether the technique could distinguish between the diesel samples from different sources/locations. The ability to differentiate or correlate diesel samples could be valuable for detecting fuel tax evasion schemes. Two fractionation techniques were used to isolate the n-alkanes from the fuel. Both ?13C and ?D values for the n-alkanes were then determined by CSIA in each sample. Plots of ?D versus ?13C with sample n-alkane points connected in order of increasing carbon number gave well separated clusters with characteristic shapes for each sample. Principal components analysis (PCA) with ?13C, ?D, or combined ?13C and ?D data on the yielded scores plots that could clearly differentiate the samples, thereby demonstrating the potential of this approach for fingerprinting fuel samples using the ?13C and ?D values.

Harvey, Scott D.; Jarman, Kristin H.; Moran, James J.; Sorensen, Christina M.; Wright, Bob W.

2011-09-15T23:59:59.000Z

371

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

E-Print Network (OSTI)

expected for K-biomass and automobile combustion particles [Arabia: Biomass/biofuel burning and fossil fuel combustion,or coal combustion. The fly ash does not resemble K-biomass

Spencer, Matthew Todd

2007-01-01T23:59:59.000Z

372

New insights into single-particle mixing state using aircraft aerosol time-of-flight mass spectrometry  

E-Print Network (OSTI)

K, and S during combustion of annual biomass, Energy Fuels,spherical combustion particles from biomass burning usingsuch as biomass burning, fossil fuel combustion, and dust

Pratt, Kerri Anne

2009-01-01T23:59:59.000Z

373

Investigations into the impact of transported particles on air pollution and climate using aerosol time-of-flight mass spectrometry  

E-Print Network (OSTI)

for fossil fuel combustion and biomass burning emissions [Arabia: Biomass/biofuel burning and fossil fuel combustion,Many K-Combustion particles are from biomass burning, but

Ault, Andrew Phillip

2010-01-01T23:59:59.000Z

374

New insights into single-particle mixing state using aircraft aerosol time-of-flight mass spectrometry  

E-Print Network (OSTI)

epsomite (MgSO 4. 7H 2 O), trona (NaHCO 3. Na 2 CO 3. 2H 2thenardite, epsomite, trona, sylvite, carnallite, calcite/

Pratt, Kerri Anne

2009-01-01T23:59:59.000Z

375

New insights into single-particle mixing state using aircraft aerosol time-of-flight mass spectrometry  

E-Print Network (OSTI)

traffic-related and wood combustion sources, Anal. Chem. ,from wildfires and wood combustion, are dominated byparticles emitted from wood combustion and car exhaust. In

Pratt, Kerri Anne

2009-01-01T23:59:59.000Z

376

Inductively Coupled Plasma-Mass Spectrometry with Collision/Reaction Cell Technology for Analysis of Flue Gas Desulfurization Wastew aters  

Science Conference Proceedings (OSTI)

Flue gas desulfurization (FGD) wastewater is produced by pollution control equipment used on coal-fired power plants to reduce sulfur dioxide emissions to air. Wet FGD scrubbers produce an aqueous blowdown stream that contains trace levels of metals that have been adsorbed from flue gas. Power plant owners need to measure concentrations of these metals for purposes of process control, discharge monitoring, or design and operation of wastewater treatment systems. FGD water is a very difficult matrix ...

2012-09-20T23:59:59.000Z

377

Investigations into the impact of transported particles on air pollution and climate using aerosol time-of-flight mass spectrometry  

E-Print Network (OSTI)

Additional residual fuel oil sources, such as refineries,emissions from residual oil sources such as ships andregulations and residual oil sources such as shipping

Ault, Andrew Phillip

2010-01-01T23:59:59.000Z

378

New insights into single-particle mixing state using aircraft aerosol time-of-flight mass spectrometry  

E-Print Network (OSTI)

of contact nucleation in ice phase initiation in clouds, J.of cloud sampling. The ice phase CVI sample was collectedthe liquid, mixed, and ice phase sampling, externally mixed

Pratt, Kerri Anne

2009-01-01T23:59:59.000Z

379

Investigations into the impact of transported particles on air pollution and climate using aerosol time-of-flight mass spectrometry  

E-Print Network (OSTI)

early initiation of the ice phase, increasing riming rates,the melting level in the ice phase portion of precipitatingFor mixed phase clouds, enhancement of ice concentrations is

Ault, Andrew Phillip

2010-01-01T23:59:59.000Z

380

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

E-Print Network (OSTI)

4.5 Uranium Isotope Ratio Measurements . . . . . .4.32 Uranium sputtered from three U-rich materials of varying uranium isotopic

Isselhardt, Brett Hallen

2011-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "imaging 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

Pyrolysis of Organic Molecules Relevant to Combustion as Monitored by Photoionization Time-of-Flight Mass Spectrometry  

E-Print Network (OSTI)

OF 2-METHOXY TRIMETHYL BUTANE-d 6 (MTMB-d 6 ) VI. PYROLYSISexception of propane and butane. 7 This approach is powerfulthe exceptions of propane and butane. The performance of VUV

Weber, Kevin Howard

2010-01-01T23:59:59.000Z

382

Synchrotron Vacuum-Ultraviolet Postionization Mass Spectrometry with Laser and Ion Probes for Intact Molecular Spatial Mapping of Lignin  

E-Print Network (OSTI)

H. ; Kishimoto, T. ; Fukushima, K. Biomacromolecules (12)Kato, T. ; Tsuji, Y. ; Fukushima, K. Biomacromolecules 2005,Kato, T. ; Tsuji, Y. ; Fukushima, K. Biomacromolecules 2005,

Takahashi, Lynelle Kazue

2011-01-01T23:59:59.000Z

383

Laser post-ionization secondary neutral mass spectrometry for ultra-trace analysis of samples from space return missions  

E-Print Network (OSTI)

. Cass Avenue, Building 200, Argonne, IL 60439, USA b Universita¨t Duisburg-Essen, Campus Duisburg of micron-sized particles embedded in aerogel collector material. The Genesis mission [2] has returned

Wucher, Andreas

384

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

E-Print Network (OSTI)

a laser system intended to make reproducible measurements ofof uranium measurements. The new laser system should be used

Isselhardt, Brett Hallen

2011-01-01T23:59:59.000Z

385

Determination of the Relative Amount of Fluorine in Uranium Oxyfluoride Particles using Secondary Ion Mass Spectrometry and Optical Spectroscopy  

Science Conference Proceedings (OSTI)

Both nuclear forensics and environmental sampling depend upon laboratory analysis of nuclear material that has often been exposed to the environment after it has been produced. It is therefore important to understand how those environmental conditions might have changed the chemical composition of the material over time, particularly for chemically sensitive compounds. In the specific case of uranium enrichment facilities, uranium-bearing particles stem from small releases of uranium hexafluoride, a highly reactive gas that hydrolyzes upon contact with moisture from the air to form uranium oxyfluoride (UO{sub 2}F{sub 2}) particles. The uranium isotopic composition of those particles is used by the International Atomic Energy Agency (IAEA) to verify whether a facility is compliant with its declarations. The present study, however, aims to demonstrate how knowledge of time-dependent changes in chemical composition, particle morphology and molecular structure can contribute to an even more reliable interpretation of the analytical results. We prepared a set of uranium oxyfluoride particles at the Institute for Reference Materials and Measurements (IRMM, European Commission, Belgium) and followed changes in their composition, morphology and structure with time to see if we could use these properties to place boundaries on the particle exposure time in the environment. Because the rate of change is affected by exposure to UV-light, humidity levels and elevated temperatures, the samples were subjected to varying conditions of those three parameters. The NanoSIMS at LLNL was found to be the optimal tool to measure the relative amount of fluorine in individual uranium oxyfluoride particles. At PNNL, cryogenic laser-induced time-resolved U(VI) fluorescence microspectroscopy (CLIFS) was used to monitor changes in the molecular structure.

Kips, R; Kristo, M J; Hutcheon, I D; Amonette, J; Wang, Z; Johnson, T; Gerlach, D; Olsen, K B

2009-05-29T23:59:59.000Z

386

Estimation theoretical image restoration  

E-Print Network (OSTI)

In this thesis, we have developed an extensive study to evaluate image restoration from a single image, colored or monochromatic. Using a mixture of Gaussian and Poisson noise process, we derived an objective function to ...

Dolne, Jean J

2008-01-01T23:59:59.000Z

387

Spectrographic imaging system  

DOE Patents (OSTI)

An imaging system for providing spectrographically resolved images. The system incorporates a one-dimensional spatial encoding mask which enables an image to be projected onto a two-dimensional image detector after spectral dispersion of the image. The dimension of the image which is lost due to spectral dispersion on the two-dimensional detector is recovered through employing a reverse transform based on presenting a multiplicity of different spatial encoding patterns to the image. The system is especially adapted for detecting Raman scattering of monochromatic light transmitted through or reflected from physical samples. Preferably, spatial encoding is achieved through the use of Hadamard mask which selectively transmits or blocks portions of the image from the sample being evaluated.

Morris, Michael D. (Ann Arbor, MI); Treado, Patrick J. (Ann Arbor, MI)

1991-01-01T23:59:59.000Z

388

Synthetic stereoscopic panoramic images  

Science Conference Proceedings (OSTI)

Presented here is a discussion of the techniques required to create stereoscopic panoramic images. Such images allow interactive exploration of 3D environments with stereoscopic depth cues. If projected in a surround display environment they can engage ...

Paul Bourke

2006-10-01T23:59:59.000Z

389

Nuclear Imaging instrumentation  

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

Nuclear Imaging instrumentation Advances in gamma-ray detection and imaging have increased the pace of discovery in a broad cross-section of the sciences ranging from nuclear...

390

Document Imaging | Department of Energy  

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

Document Imaging Document Imaging Employee Services Cafeterias Conferencing and Special Events Copy Services Document Imaging Exchange Visitors Program Facility Operations Food...

391

NIST Image Gallery: Search  

Science Conference Proceedings (OSTI)

... Search Tips - Search index includes image titles, descriptions, other text fields - Searches are case-insensitive - Keyword2 is optional. ...

392

Cell Image Visualization  

Science Conference Proceedings (OSTI)

... Biological cell image analysis projects include methods to measure cell segmentation accuracy and new segmentation methods to track live cells. ...

2011-06-17T23:59:59.000Z

393

Video image position determination  

DOE Patents (OSTI)

An optical beam position controller in which a video camera captures an image of the beam in its video frames, and conveys those images to a processing board which calculates the centroid coordinates for the image. The image coordinates are used by motor controllers and stepper motors to position the beam in a predetermined alignment. In one embodiment, system noise, used in conjunction with Bernoulli trials, yields higher resolution centroid coordinates.

Christensen, Wynn (Los Alamos, NM); Anderson, Forrest L. (Bernalillo, NM); Kortegaard, Birchard L. (Los Alamos, NM)

1991-01-01T23:59:59.000Z

394

Imaging with Scattered Neutrons  

E-Print Network (OSTI)

We describe a novel experimental technique for neutron imaging with scattered neutrons. These scattered neutrons are of interest for condensed matter physics, because they permit to reveal the local distribution of incoherent and coherent scattering within a sample. In contrast to standard attenuation based imaging, scattered neutron imaging distinguishes between the scattering cross section and the total attenuation cross section including absorption. First successful low-noise millimeter-resolution images by scattered neutron radiography and tomography are presented.

H. Ballhausen; H. Abele; R. Gaehler; M. Trapp; A. Van Overberghe

2006-10-30T23:59:59.000Z

395

Basic characterization of highly enriched uranium by gamma spectrometry  

E-Print Network (OSTI)

Gamma-spectrometric methods suitable for the characterization of highly enriched uranium samples encountered in illicit trafficking of nuclear materials are presented. In particular, procedures for determining the 234U, 235U, 238U, 232U and 236U contents and the age of highly enriched uranium are described. Consequently, the total uranium content and isotopic composition can be calculated. For determining the 238U and 232U contents a low background chamber was used. In addition, age dating of uranium was also performed using low-background spectrometry.

Nguyen, C T

2006-01-01T23:59:59.000Z

396

Basic characterization of highly enriched uranium by gamma spectrometry  

E-Print Network (OSTI)

Gamma-spectrometric methods suitable for the characterization of highly enriched uranium samples encountered in illicit trafficking of nuclear materials are presented. In particular, procedures for determining the 234U, 235U, 238U, 232U and 236U contents and the age of highly enriched uranium are described. Consequently, the total uranium content and isotopic composition can be calculated. For determining the 238U and 232U contents a low background chamber was used. In addition, age dating of uranium was also performed using low-background spectrometry.

Cong Tam Nguyen; Jozsef Zsigrai

2005-08-25T23:59:59.000Z

397

Near-Electrode Imager  

DOE Patents (OSTI)

An apparatus, near-electrode imager, for employing nuclear magnetic resonance imaging to provide in situ measurements of electrochemical properties of a sample as a function of distance from a working electrode. The near-electrode imager use the radio frequency field gradient within a cylindrical toroid cavity resonator to provide high-resolution nuclear magnetic resonance spectral information on electrolyte materials.

Rathke, Jerome W.; Klingler, Robert J.; Woelk, Klaus; Gerald, Rex E.,II

1999-05-01T23:59:59.000Z

398

Acoustic Imaging Suite  

INL’s acoustic imaging technology improves methods of capturing moving images of a specified object by using a photorefractive effect to produce a full-field image of the object without using a probe to perform a full scan of the object. INL ...

399

Medical imaging systems  

Science Conference Proceedings (OSTI)

A medical imaging system provides simultaneous rendering of visible light and diagnostic or functional images. The system may be portable, and may include adapters for connecting various light sources and cameras in open surgical environments or laparascopic or endoscopic environments. A user interface provides control over the functionality of the integrated imaging system. In one embodiment, the system provides a tool for surgical pathology.

Frangioni, John V

2013-06-25T23:59:59.000Z

400

Diagnostic Imaging Emergency Medicine  

E-Print Network (OSTI)

UC Davis Veterinary Diagnostic Imaging Symposium Emergency Medicine May 15, 2011 Gladys Valley Hall devoted to triage, assessment, and imaging diagnostics in emergency medicine. Speakers in this year's symposium include specialists in diagnostic imaging, and emergency and critical care. Sunday May 15, 2011 8

Hammock, Bruce D.

Note: This page contains sample records for the topic "imaging 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

Mass-sensitive chemical preconcentrator  

DOE Patents (OSTI)

A microfabricated mass-sensitive chemical preconcentrator actively measures the mass of a sample on an acoustic microbalance during the collection process. The microbalance comprises a chemically sensitive interface for collecting the sample thereon and an acoustic-based physical transducer that provides an electrical output that is proportional to the mass of the collected sample. The acoustic microbalance preferably comprises a pivot plate resonator. A resistive heating element can be disposed on the chemically sensitive interface to rapidly heat and release the collected sample for further analysis. Therefore, the mass-sensitive chemical preconcentrator can optimize the sample collection time prior to release to enable the rapid and accurate analysis of analytes by a microanalytical system.

Manginell, Ronald P. (Albuquerque, NM); Adkins, Douglas R. (Albuquerque, NM); Lewis, Patrick R. (Albuquerque, NM)

2007-01-30T23:59:59.000Z

402

Neutrino Mass and Grand Unification  

E-Print Network (OSTI)

Seesaw mechanism appears to be the simplest and most appealing way to understand small neutrino masses observed in recent experiments. It introduces three right handed neutrinos with heavy masses to the standard model, with at least one mass required by data to be close to the scale of conventional grand unified theories. This may be a hint that the new physics scale implied by neutrino masses and grand unification of forces are one and the same. Taking this point of view seriously, I explore different ways to resolve the puzzle of large neutrino mixings in grand unified theories such as SO(10) and models based on its subgroup $SU(2)_L\\times SU(2)_R\\times SU(4)_c$.

R. N. Mohapatra

2004-12-03T23:59:59.000Z

403

Thermal Mass and Demand Response  

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

Thermal Mass and Demand Response Speaker(s): Gregor Henze Phil C. Bomrad Date: November 2, 2011 - 12:00pm Location: 90-4133 Seminar HostPoint of Contact: Janie Page The topic of...

404

Neutrino Mass and Flavour Models  

E-Print Network (OSTI)

We survey some of the recent promising developments in the search for the theory behind neutrino mass and tri-bimaximal mixing, and indeed all fermion masses and mixing. We focus in particular on models with discrete family symmetry and unification, and show how such models can also solve the SUSY flavour and CP problems. We also discuss the theoretical implications of the measurement of a non-zero reactor angle, as hinted at by recent experimental measurements.

King, Stephen F

2009-01-01T23:59:59.000Z

405

Neutrino Mass and Flavour Models  

E-Print Network (OSTI)

We survey some of the recent promising developments in the search for the theory behind neutrino mass and tri-bimaximal mixing, and indeed all fermion masses and mixing. We focus in particular on models with discrete family symmetry and unification, and show how such models can also solve the SUSY flavour and CP problems. We also discuss the theoretical implications of the measurement of a non-zero reactor angle, as hinted at by recent experimental measurements.

Stephen F King

2009-09-16T23:59:59.000Z

406

Demand Shifting with Thermal Mass in Light and Heavy Mass Commercial Buildings  

E-Print Network (OSTI)

effort to understand pre-cooling thermal mass as a Demandof Building Thermal Mass to Offset Cooling Loads. ” ASHRAEKey words: Pre-cooling, demand response, thermal mass

Xu, Peng

2010-01-01T23:59:59.000Z

407

Shape-based image retrieval applied to trademark images  

Science Conference Proceedings (OSTI)

In this chapter, we propose a new shape-based, query-by-example, image database retrieval method that is able to match a query image to one of the images in the database, based on a whole or partial match. The proposed method has two key components: ... Keywords: image databases, shape analysis, shape representation, shape-based image retrieval, trademark image retrieval

Ossama El Badawy; Mohamed Kamel

2004-01-01T23:59:59.000Z

408

OpenEI Community - images  

Open Energy Info (EERE)

Image upload with broken thumbnail image http:en.openei.orgcommunitydiscussionimage-upload-broken-thumbnail-image

OpenEI users can upload images to the wiki by typing a new...

409

Similarity Retrieval of Trademark Images  

Science Conference Proceedings (OSTI)

The Artisan system retrieves abstract trademark images by shape similarity. It analyzes each image to characterize key shape components, grouping image regions into families that potentially mirror human image perception, and then derives characteristic ...

John P. Eakins; Jago M. Boardman; Margaret E. Graham

1998-04-01T23:59:59.000Z

410

SNAP Image Gallery  

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

Images Images Cutaway image of SNAP A cutaway illustration of SNAP showing some of the interior optics. Cutaway image of SNAP A computer generated cutaway illustration of SNAP Cutaway image of SNAP's primary mirror A computer generated cutaway illustration of SNAP's primary mirror image of SNAP spacecraft A computer generated illustration of the SNAP spacecraft computer generated image of SNAP A computer generated illustration of SNAP Before-and-after pictures (and Hubble Space Telescope picture) of a high-redshift supernovae discovered by the Supernova Cosmology Project in March, 1998. Before-and-after pictures (and Hubble Space Telescope picture) of a high-redshift supernovae discovered in March, 1998. This observaton showed that the expansion of the universe was accelerarting. Credit: High Redshift Supernova Search Supernova Cosmology Project

411

Gridless Overtone Mobility Spectrometry Steven M. Zucker, Michael A. Ewing, and David E. Clemmer*  

E-Print Network (OSTI)

of new mobility-based techniques are under development, including traveling wave ion mobilityGridless Overtone Mobility Spectrometry Steven M. Zucker, Michael A. Ewing, and David E. Clemmer Information ABSTRACT: A novel overtone mobility spectrometry (OMS) instrument utilizing a gridless elimination

Clemmer, David E.

412

DETERMINATION OF LITHIUM BY FLAME EMISSION SPECTROMETRY Background Reading: Harris, 7th  

E-Print Network (OSTI)

DETERMINATION OF LITHIUM BY FLAME EMISSION SPECTROMETRY Background Reading: Harris, 7th ed., Chap of this experiment is to acquaint you with flame emission spectrometry. The determination of lithium, and all other. It uses a propane/air flame. #12;Lithium by Flame Emission, Page 2 Identify the burner with its nebulizer

Weston, Ken

413

Development of a variable-temperature ion mobility/ time-of-flight mass spectrometer for separation of electronic isomers  

E-Print Network (OSTI)

The construction of a liquid nitrogen-cooled ion mobility spectrometer coupled with time-of-flight mass spectrometry was implemented to demonstrate the ability to discriminate between electronic isomers. Ion mobility allows for the separation of ions based on differing cross-sections-to-charge ratio. This allows for the possible discrimination of species with same mass if the ions differ by cross-section. Time-offlight mass spectrometry was added to mass identify the separated peak for proper identification. A liquid nitrogen-cooled mobility cell was employed for a two-fold purpose. First, the low temperatures increase the peak resolution to aid in resolving the separated ions. This is necessary when isomers may have similar cross-sections. Second, low temperature shortens the mean free path and decreases the neutral buffer gas speeds allowing for more interactions between the ions and the drift gas. Kr2+ study was performed to verify instrument performance. The variable-temperature ion mobility spectrometer was utilized to separate the distonic and conventional ion forms of CH3OH, CH3F, and CH3NH2 and to discriminate between the keto and enol forms of the acetone radical cation. Density functional theory and ab initio calculations were employed to aid in proper identification of separating isomers. Monte Carlo integration tools were also developed to predict ion cross-section and resolution within a buffer gas.

Verbeck, Guido Fridolin

2006-05-01T23:59:59.000Z

414

QLC relation and neutrino mass hierarchy  

E-Print Network (OSTI)

neutrino mass matrix is generated at high energies, s 12 = cneutrino mass matrix is generated at low energy scales. Ontrino mass matrix is generated at some high energy scale. We

Ferrandis, Javier

2009-01-01T23:59:59.000Z

415

Energy or Mass and Interaction  

E-Print Network (OSTI)

A review. Problems: 1-Many empirical parameters and large dimension number; 2-Gravitation and Electrodynamics are challenged by dark matter and energy. Energy and nonlinear electrodynamics are fundamental in a unified nonlinear interaction. Nuclear energy appears as nonlinear SU(2) magnetic energy. Gravitation and electromagnetism are unified giving Einstein's equation and a geometric energy momentum tensor. A solution energy in the newtonian limit gives the gravitational constant G. Outside of this limit G is variable. May be interpreted as dark matter or energy. In vacuum, known gravitational solutions are obtained. Electromagnetism is an SU(2) subgroup. A U(1) limit gives Maxwell's equations. Geometric fields determine a generalized Dirac equation and are the germ of quantum physics. Planck's h and of Einstein's c are given by the potential and the metric. Excitations have quanta of charge, flux and spin determining the FQHE. There are only three stable 1/2 spin fermions. Mass is a form of energy. The rest energies of the fermions give the proton/electron mass ratio. Potential excitations have energies equal to the weak boson masses allowing a geometric interpretation of Weinberg's angle. SU(2) gives the anomalous magnetic moments of proton, electron, neutron and generates nuclear range attractive potentials strong enough to produce the binding energies of the deuteron and other nuclides. Lepton and meson masses are due to topological excitations. The geometric mass spectrum is satisfactory. The proton has a triple structure. The alpha constant is a geometric number.

Gustavo R Gonzalez-Martin

2010-07-19T23:59:59.000Z

416

Photon and graviton mass limits  

Science Conference Proceedings (OSTI)

We review past and current studies of possible long-distance, low-frequency deviations from Maxwell electrodynamics and Einstein gravity. Both have passed through three phases: (1) Testing the inverse-square laws of Newton and Coulomb, (2) Seeking a nonzero value for the rest mass of photon or graviton, and (3) Considering more degrees of freedom, allowing mass while preserving gauge or general-coordinate invariance. For electrodynamics there continues to be no sign of any deviation. Since our previous review the lower limit on the photon Compton wavelength (associated with weakening of electromagnetic fields in vacuum over large distance scale) has improved by four orders of magnitude, to about one astronomical unit. Rapid current progress in astronomical observations makes it likely that there will be further advances. These ultimately could yield a bound exceeding galactic dimensions, as has long been contemplated. Meanwhile, for gravity there have been strong arguments about even the concept of a graviton rest mass. At the same time there are striking observations, commonly labeled 'dark matter' and 'dark energy' that some argue imply modified gravity. This makes the questions for gravity much more interesting. For dark matter, which involves increased attraction at large distances, any explanation by modified gravity would be qualitatively different from graviton mass. Because dark energy is associated with reduced attraction at large distances, it might be explained by a graviton-mass-like effect.

Nieto, Michael [Los Alamos National Laboratory; Goldhaber Scharff, Alfred [SUNY

2008-01-01T23:59:59.000Z

417

Cranking mass parameters for fission  

E-Print Network (OSTI)

A formalism for semi-adiabatic cranking mass parameters is presented. For the fission process of 234U, the time-dependent pairing equations of motion were used to calculate the excitation energy and to extract values of the cranking inertia. A fission barrier is determined by minimizing the action trajectory in a five dimensional configuration space spanned by elongation, necking, deformations of fragments and mass-asymmetry. The deformation energy is computed in the the frame of the microscopic-macroscopic model. The two center shell model with Woods-Saxon potentials is used in this context. Values of the inertia for excited fissioning systems are reported. A dependence between the cranking mass parameters and the intrinsic excitation energy is evidenced.

M. Mirea; R. C. Bobulescu

2009-09-11T23:59:59.000Z

418

ARM - Measurement - Hydrometeor image  

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

image image ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Hydrometeor image Images of hydrometeors from which one can derive characteristics such as size and shape. Categories Cloud Properties Instruments The above measurement is considered scientifically relevant for the following instruments. Refer to the datastream (netcdf) file headers of each instrument for a list of all available measurements, including those recorded for diagnostic or quality assurance purposes. Field Campaign Instruments LEARJET : Lear Jet PARTIMG : Particle imager UAV-PROTEUS-MICRO : Proteus Cloud Microphysics Instruments SPEC-CPI : Stratton Park Engineering Company - Cloud particle imager UAV-PROTEUS : UAV Proteus

419

Video Toroid Cavity Imager  

DOE Patents (OSTI)

A video toroid cavity imager for in situ measurement of electrochemical properties of an electrolytic material sample includes a cylindrical toroid cavity resonator containing the sample and employs NMR and video imaging for providing high-resolution spectral and visual information of molecular characteristics of the sample on a real-time basis. A large magnetic field is applied to the sample under controlled temperature and pressure conditions to simultaneously provide NMR spectroscopy and video imaging capabilities for investigating electrochemical transformations of materials or the evolution of long-range molecular aggregation during cooling of hydrocarbon melts. The video toroid cavity imager includes a miniature commercial video camera with an adjustable lens, a modified compression coin cell imager with a fiat circular principal detector element, and a sample mounted on a transparent circular glass disk, and provides NMR information as well as a video image of a sample, such as a polymer film, with micrometer resolution.

Gerald, Rex E. II; Sanchez, Jairo; Rathke, Jerome W.

2004-08-10T23:59:59.000Z

420

Video image position determination  

DOE Patents (OSTI)

The present invention generally relates to the control of video and optical information and, more specifically, to control systems utilizing video images to provide control. Accurate control of video images and laser beams is becoming increasingly important as the use of lasers for machine, medical and experimental processes escalates. In, AURORA, an installation at Los Alamos National Laboratory dedicated to laser fusion research, it is necessary to precisely control the path and angle of up to 96 lasers beams. This invention is comprised of an optical beam position controller in which a video camera captures an image of the beam in its video frames, and conveys those images to a processing board which calculates the centroid coordinates for the image. The image coordinates are used by motor controllers and stepper motors to position the beam in a predetermined alignment. In one embodiment, system noise, used in conjunction with Bernoulli trials, yields higher resolution centroid coordinates.

Christensen, W.; Anderson, F.L.; Kortegaard, B.L.

1990-01-01T23:59:59.000Z

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


421

Video image position determination  

DOE Patents (OSTI)

The present invention generally relates to the control of video and optical information and, more specifically, to control systems utilizing video images to provide control. Accurate control of video images and laser beams is becoming increasingly important as the use of lasers for machine, medical and experimental processes escalates. In, AURORA, an installation at Los Alamos National Laboratory dedicated to laser fusion research, it is necessary to precisely control the path and angle of up to 96 lasers beams. This invention is comprised of an optical beam position controller in which a video camera captures an image of the beam in its video frames, and conveys those images to a processing board which calculates the centroid coordinates for the image. The image coordinates are used by motor controllers and stepper motors to position the beam in a predetermined alignment. In one embodiment, system noise, used in conjunction with Bernoulli trials, yields higher resolution centroid coordinates.

Christensen, W.; Anderson, F.L.; Kortegaard, B.L.

1990-12-31T23:59:59.000Z

422

Mass transport through polycrystalline microstructures  

SciTech Connect

Mass transport properties are important in polycrystalline materials used as protective films. Traditionally, such properties have been studied by examining model polycrystalline structures, such as a regular array of straight grain boundaries. However, these models do not account for a number of features of real grain ensembles, including the grain size distribution and variations in grain shape. In this study, a finite difference scheme is developed to study transient and steady-state mass transport through realistic two dimensional polycrystalline microstructures. Comparisons with the transport properties of traditional model microstructures provide regimes of applicability of such models. The effects of microstructural parameters such as average grain size are examined.

Swiler, T.P.; Holm, E.A.; Young, M.F.; Wright, S.A.

1994-12-31T23:59:59.000Z

423

Alternative Fuels Data Center: Mass Transit  

Alternative Fuels and Advanced Vehicles Data Center (EERE)

Mass Transit to Mass Transit to someone by E-mail Share Alternative Fuels Data Center: Mass Transit on Facebook Tweet about Alternative Fuels Data Center: Mass Transit on Twitter Bookmark Alternative Fuels Data Center: Mass Transit on Google Bookmark Alternative Fuels Data Center: Mass Transit on Delicious Rank Alternative Fuels Data Center: Mass Transit on Digg Find More places to share Alternative Fuels Data Center: Mass Transit on AddThis.com... More in this section... Idle Reduction Parts & Equipment Maintenance Driving Behavior Fleet Rightsizing System Efficiency Ridesharing Mass Transit Active Transit Multi-Modal Transportation Telework Mass Transit Passenger-Miles per Gallon Passenger-miles per gallon (pmpg) is a metric for comparing mass transit and rideshare with typical passenger vehicle travel. Transportation system

424

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

425

Ferroelectric optical image comparator  

DOE Patents (OSTI)

A ferroelectric optical image comparator has a lead lanthanum zirconate titanate thin-film device which is constructed with a semi-transparent or transparent conductive first electrode on one side of the thin film, a conductive metal second electrode on the other side of the thin film, and the second electrode is in contact with a nonconducting substrate. A photoinduced current in the device represents the dot product between a stored image and an image projected onto the first electrode. One-dimensional autocorrelations are performed by measuring this current while displacing the projected image. 7 figures.

Butler, M.A.; Land, C.E.; Martin, S.J.; Pfeifer, K.B.

1993-11-30T23:59:59.000Z

426

Ferroelectric optical image comparator  

DOE Patents (OSTI)

A ferroelectric optical image comparator has a lead lanthanum zirconate titanate thin-film device which is constructed with a semi-transparent or transparent conductive first electrode on one side of the thin film, a conductive metal second electrode on the other side of the thin film, and the second electrode is in contact with a nonconducting substrate. A photoinduced current in the device represents the dot product between a stored image and an image projected onto the first electrode. One-dimensional autocorrelations are performed by measuring this current while displacing the projected image.

Butler, Michael A. (Albuquerque, NM); Land, Cecil E. (Albuquerque, NM); Martin, Stephen J. (Albuquerque, NM); Pfeifer, Kent B. (Los Lunas, NM)

1993-01-01T23:59:59.000Z

427

Image Shift Measurement  

Science Conference Proceedings (OSTI)

... Set the write directory to a new folder for the cropped images. Use Process Folder / Text file / Template to make the boiler plate processing file. ...

428

Manhattan Project: Places Images  

Office of Scientific and Technical Information (OSTI)

PLACES IMAGES PLACES IMAGES Resources > Photo Gallery Scroll down to see each of these images individually. The images are: 1. Remains of a Shinto Shrine, Nagasaki, October 1945 (courtesy the United States Marine Corps, Lieutenant R. J. Battersby, photographer, via the National Archives); 2. University of California, Berkeley, 1940 (courtesy the Lawrence Berkeley National Laboratory); 3. Aerial photograph of the Trinity Site after the test (courtesy the Federation of American Scientists); 4. Aerial photograph of Hiroshima before the bombing; 5. Columbia University, 1903 (courtesy the Library of Congress; this photograph originated from the Detroit Publishing Company; it was a 1949 gift to the Library of Congress from the State Historical Society of Colorado).

429

Quantitative luminescence imaging system  

DOE Patents (OSTI)

The QLIS images and quantifies low-level chemiluminescent reactions in an electromagnetic field. It is capable of real time nonperturbing measurement and simultaneous recording of many biochemical and chemical reactions such as luminescent immunoassays or enzyme assays. The system comprises image transfer optics, a low-light level digitizing camera with image intensifying microchannel plates, an image process or, and a control computer. The image transfer optics may be a fiber image guide with a bend, or a microscope, to take the light outside of the RF field. Output of the camera is transformed into a localized rate of cumulative digitalized data or enhanced video display or hard-copy images. The system may be used as a luminescent microdosimetry device for radiofrequency or microwave radiation, as a thermal dosimeter, or in the dosimetry of ultra-sound (sonoluminescence) or ionizing radiation. It provides a near-real-time system capable of measuring the extremely low light levels from luminescent reactions in electromagnetic fields in the areas of chemiluminescence assays and thermal microdosimetry, and is capable of near-real-time imaging of the sample to allow spatial distribution analysis of the reaction. It can be used to instrument three distinctly different irradiation configurations, comprising (1) RF waveguide irradiation of a small Petri-dish-shaped sample cell, (2) RF irradiation of samples in a microscope for the microscopic imaging and measurement, and (3) RF irradiation of small to human body-sized samples in an anechoic chamber. 22 figs.

Erwin, D.N.; Kiel, J.L.; Batishko, C.R.; Stahl, K.A.

1990-08-14T23:59:59.000Z

430

Imaging Beyond Optics  

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

Views" piece in that same issue. "Generations of astronomers have used interferometric tests to achieve the proper shape of their mirrors before using them to image the heavens....

431

Quantitative luminescence imaging system  

DOE Patents (OSTI)

The QLIS images and quantifies low-level chemiluminescent reactions in an electromagnetic field. It is capable of real time nonperturbing measurement and simultaneous recording of many biochemical and chemical reactions such as luminescent immunoassays or enzyme assays. The system comprises image transfer optics, a low-light level digitizing camera with image intensifying microchannel plates, an image process or, and a control computer. The image transfer optics may be a fiber image guide with a bend, or a microscope, to take the light outside of the RF field. Output of the camera is transformed into a localized rate of cumulative digitalized data or enhanced video display or hard-copy images. The system may be used as a luminescent microdosimetry device for radiofrequency or microwave radiation, as a thermal dosimeter, or in the dosimetry of ultra-sound (sonoluminescence) or ionizing radiation. It provides a near-real-time system capable of measuring the extremely low light levels from luminescent reactions in electromagnetic fields in the areas of chemiluminescence assays and thermal microdosimetry, and is capable of near-real-time imaging of the sample to allow spatial distribution analysis of the reaction. It can be used to instrument three distinctly different irradiation configurations, comprising (1) RF waveguide irradiation of a small Petri-dish-shaped sample cell, (2) RF irradiation of samples in a microscope for the microscopie imaging and measurement, and (3) RF irradiation of small to human body-sized samples in an anechoic chamber.

Erwin, David N. (San Antonio, TX); Kiel, Johnathan L. (San Antonio, TX); Batishko, Charles R. (West Richland, WA); Stahl, Kurt A. (Richland, WA)

1990-01-01T23:59:59.000Z

432

Kursk Site Image #1  

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

Graphs Image KRS-1: Clipping above-ground biomass at the Kursk grassland site, Russia. (Dr. Kira Khodashova and student Nina N., Moscow State University, are estimating monthly...

433

Research on Stability Criterion of Furnace Flame Combustion Based on Image Processing  

Science Conference Proceedings (OSTI)

This paper proposes and analyzes the stability criterion of furnace flame combustion based on image processing, which uses the maximum criterion of gray scale difference, the distance criterion of gravity center and mass center in the high temperature ... Keywords: image processing, stability, flame detection, boiler safety

Rongbao Chen, Wuting Fan, Jingci Bian, Fanhui Meng

2012-12-01T23:59:59.000Z

434

High-Resolution Serum Proteomic Profiling of Alzheimer Disease Samples Reveals Disease- Specific, Carrier-Protein–Bound Mass Signatures  

E-Print Network (OSTI)

Background: Researchers typically search for disease markers using a “targeted ” approach in which a hypothesis about the disease mechanism is tested and experimental results either confirm or disprove the involvement of a particular gene or protein in the disease. Recently, there has been interest in developing disease diagnostics based on unbiased quantification of differences in global patterns of protein and peptide masses, typically in blood from individuals with and without disease. We combined a suite of methods and technologies, including novel sample preparation based on carrier-protein capture and biomarker enrichment, highresolution mass spectrometry, a unique cohort of wellcharacterized persons with and without Alzheimer disease (AD), and powerful bioinformatic analysis, that add statistical and procedural robustness to biomarker discovery from blood. Methods: Carrier-protein–bound peptides were isolated from serum samples by affinity chromatography, and peptide mass spectra were acquired by a matrixassisted laser desorption/ionization (MALDI) orthogo-

Mary F. Lopez; Alvydas Mikulskis; Scott Kuzdzal; David A. Bennett; Jeremiah Kelly; Eva Golenko; Joseph Dicesare; Eric Denoyer; Wayne F. Patton; Richard Ediger; Tillmann Ziegert; Christopher Lynch; Susan Kramer; Gordon R. Whiteley; Michael R. Wall; David P. Mannion; John S. Rakitan; Gershon M. Wolfe

2005-01-01T23:59:59.000Z

435

Automatic Image Orientation Determination with Natural Image Statistics  

E-Print Network (OSTI)

Automatic Image Orientation Determination with Natural Image Statistics Siwei Lyu Dept. of Computer a new method for automatically determining image orientations. This method is based on a set of natural image statistics collected from a multi- scale multi-orientation image decomposition (e.g., wavelets

Lyu, Siwei

436

Quantum Imaging: Enhanced Image Formation Using Quantum States of Light  

E-Print Network (OSTI)

Quantum Imaging: Enhanced Image Formation Using Quantum States of Light Robert W. Boyd, Kam Wai, University of Rochester, Rochester, NY 14627, USA ABSTRACT We review recent research in the field of quantum imaging. Quantum imaging deals with the formation of images that possess higher resolution or better

Boyd, Robert W.

437

Time of flight mass spectrometer  

DOE Patents (OSTI)

A time-of-flight mass spectrometer is described in which ions are desorbed from a sample by nuclear fission fragments, such that desorption occurs at the surface of the sample impinged upon by the fission fragments. This configuration allows for the sample to be of any thickness, and eliminates the need for complicated sample preparation.

Ulbricht, Jr., William H. (Arvada, CO)

1984-01-01T23:59:59.000Z

438

Mass modification experiment definition study  

SciTech Connect

This report summarizes an attempt to find an experiment that would test the Haisch, Rueda, and Puthoff (HRP) conjecture that the mass and inertia of a body are induced effects brought about by changes in the quantum-fluctuation energy of the vacuum. It was not possible, however, to identify a definitive experiment. But, it was possible to identify an experiment that might be able to prove or disprove that the inertial mass of a body can be altered by making changes in the vacuum surrounding the body. Other experiments, which do not involve mass modification, but which teach something about the vacuum, were also defined and included in a ranked list of experiments. This report also contains an annotated bibliography. An interesting point raised by this paper is this: We can estimate the `vacuum energy density` to be 10{sup 108} J/cc, and the vacuum mass density to be 10{sup 94} g/cc, much higher numbers than those associated with nuclear energy. Although the field of `electromagnetic fluctuation energy of the vacuum` is admittedly an esoteric, little-understood field, it does seem to have definite potential as an energy source. 47 refs.

Forward, R.L. [Forward Unlimited, Malibu, CA (United States)

1996-12-31T23:59:59.000Z

439

Comments on the mass of the Photon  

E-Print Network (OSTI)

De Broglie believed that the photon has a mass, a view shared by a few others. Quite recently, the author has argued that the photon has a mass which is consistent with the latest experimental limits. In the present paper we point out that there is experimental evidence for this mass and also give a theoretical demonstration of the photon mass.

Burra G. Sidharth

2006-07-24T23:59:59.000Z

440

Heart imaging method  

DOE Patents (OSTI)

A method for providing an image of the human heart's electrical system derives time-of-flight data from an array of EKG electrodes and this data is transformed into phase information. The phase information, treated as a hologram, is reconstructed to provide an image in one or two dimensions of the electrical system of the functioning heart.

Collins, H. Dale (Richland, WA); Gribble, R. Parks (Richland, WA); Busse, Lawrence J. (Littleton, CO)

1991-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "imaging 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

Medical imaging systems  

DOE Patents (OSTI)

A medical imaging system provides simultaneous rendering of visible light and fluorescent images. The system may employ dyes in a small-molecule form that remains in a subject's blood stream for several minutes, allowing real-time imaging of the subject's circulatory system superimposed upon a conventional, visible light image of the subject. The system may also employ dyes or other fluorescent substances associated with antibodies, antibody fragments, or ligands that accumulate within a region of diagnostic significance. In one embodiment, the system provides an excitation light source to excite the fluorescent substance and a visible light source for general illumination within the same optical guide that is used to capture images. In another embodiment, the system is configured for use in open surgical procedures by providing an operating area that is closed to ambient light. More broadly, the systems described herein may be used in imaging applications where a visible light image may be usefully supplemented by an image formed from fluorescent emissions from a fluorescent substance that marks areas of functional interest.

Frangioni, John V. (Wayland, MA)

2012-07-24T23:59:59.000Z

442

DOUBLE MAJORS Imaging Science + ...  

E-Print Network (OSTI)

DOUBLE MAJORS Imaging Science + ... Applied Mathematics Biomedical Sciences Computer Science Undergraduate Research Internships and Cooperative Education (Co-op) (optional) Study Abroad WHY IMAGING SCIENCE Science: BS, MS, PhD Color Science: MS, PhD BS + MS/PhD Combos HUMAN VISION BIO- MEDICAL ASTRO- PHYSICS

Zanibbi, Richard

443

Manhattan Project: Image Retouching`  

Office of Scientific and Technical Information (OSTI)

Image Retouching Image Retouching Resources > Photo Gallery Smyth Report (original) Smyth Report (retouched) Images on this web site have sometimes been "retouched." In every case, however, the intention has been only to restore the image as much as possible to its original condition. Above is a rather extreme example-"before and after" versions of the cover of the Smyth Report (Henry DeWolf Smyth, Atomic Energy for Military Purposes: The Official Report on the Development of the Atomic Bomb under the Auspices of the United States Government, 1940-1945 (Princeton, NJ: Princeton University Press, 1945)). The Smyth Report was commissioned by Leslie Groves and originally issued by the Manhattan Engineer District. Princeton University Press reprinted it in book form as a "public service" with "reproduction in whole or in part authorized and permitted.") Larger versions of the same images are below.

444

GTL Image Gallery  

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

Human Genome Project Information • Genomic Science • Microbial Genome Program • sitemap • home Human Genome Project Information • Genomic Science • Microbial Genome Program • sitemap • home Announcing the New Image Gallery Visit the new Image Gallery for an expanded suite of images Biofuels Browse the 2010 "Bioenergy Research Centers: An Overview of the Science" Brochure Gallery. Browse the 2006 "Breaking the Biological Barriers to Cellulosic Ethanol: A Joint Research Agenda" Report Gallery. Browse more biofuels images (includes the June 2006 "Understanding Biomass" Primer Gallery). Systems Biology Browse the August 2005 "Genomics:GTL Roadmap: Systems Biology for Energy and Environment" Gallery. Basic Genomics Browse the Human Chromosome Gallery. Browse more Basic Genomics images. Carbon Cycling

445

User Science Images  

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

User Science Images User Science Images User Science Images Sort by: Default | Name | Date (low-high) | Date (high-low) | Category NIMROD-1.png FES: NIMROD Simulation February 18, 2010 | Author(s): Dr. Charlson C. Kim (University of Washington) | Category: Fusion Energy | URL: https://nimrodteam.org/ Download Image: NIMROD-1.png | png | 1.5 MB Trajectory of an energetic ion in a Field Reverse Configuration (FRC) magnetic field. Magnetic separatrix denoted by green surface. Spheres are colored by azimuthal velocity. Image courtesy of Charlson Kim, University of Washington; NERSC repos m487, mp21, m1552 Scheibe.png BER: Pore-Scale Fluid Flow for Subsurface Reactive Transport January 1, 2008 | Author(s): Timothy D. Scheibe, PNNL | Category: Environmental Science | URL: http://http://subsurface.pnl.gov/

446

Efficient Graffiti Image Retrieval  

Science Conference Proceedings (OSTI)

Research of graffiti character recognition and retrieval, as a branch of traditional optical character recognition (OCR), has started to gain attention in recent years. We have investigated the special challenge of the graffiti image retrieval problem and propose a series of novel techniques to overcome the challenges. The proposed bounding box framework locates the character components in the graffiti images to construct meaningful character strings and conduct image-wise and semantic-wise retrieval on the strings rather than the entire image. Using real world data provided by the law enforcement community to the Pacific Northwest National Laboratory, we show that the proposed framework outperforms the traditional image retrieval framework with better retrieval results and improved computational efficiency.

Yang, Chunlei; Wong, Pak C.; Ribarsky, William; Fan, Jianping

2012-07-05T23:59:59.000Z

447

MassMass transfer andtransfer and separation technologyseparation technology  

E-Print Network (OSTI)

) i fl id t b Massöve small units are needed (H 1 m); 2) corrosive fluids must be handledRaschig ringring packingpacking For Raschig rings with a 1" (inch) di t d h i ht l l t th Picture: WK92 diameter Laboratory tel. 3223 ; ron.zevenhoven@abo.fi RoNz eknikarationste 24302 ochSepa 13.1 Principle of operation

Zevenhoven, Ron

448

MassMass transfer andtransfer and separation technologyseparation technology  

E-Print Network (OSTI)

, spray columns (a) ­ Columns with mechanical agitators or centrifugal effects, for example see section 9.2 24302 ochSepa g g , f p rotating disc contactors (RDC) (b), Kühni columns (c) a b c 4 erföringo a b c-thermal, continuous, steady-state) can be presented as a series of N equilibrium stage contactors Massöve N

Zevenhoven, Ron

449

Edge structure preserving image denoising  

Science Conference Proceedings (OSTI)

Image denoising is important in image analysis. It is often used for pre-processing images so that subsequent image analysis is more reliable. Besides noise removal, one important requirement for image denoising procedures is that they should preserve ... Keywords: Angles, Curvature, Edges, Jump-preserving surface estimation, Local smoothing, Nonparametric regression, Surface estimation

Peihua Qiu; Partha Sarathi Mukherjee

2010-10-01T23:59:59.000Z

450

Adaptive wiener image restoration kernel  

DOE Patents (OSTI)

A method and device for restoration of electro-optical image data using an adaptive Wiener filter begins with constructing imaging system Optical Transfer Function, and the Fourier Transformations of the noise and the image. A spatial representation of the imaged object is restored by spatial convolution of the image using a Wiener restoration kernel.

Yuan, Ding (Henderson, NV)

2007-06-05T23:59:59.000Z

451

IMAGING: the Neutron Imaging Prototype Facility at HFIR | ORNL...  

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

Neutron Imaging Prototype Facility CG-1D flight tubes Neutron imaging beam line CG-1D. The CG-1D beam is used for neutron imaging measurements and can be configured for white beam...

452

Image Windows - description of data types  

Science Conference Proceedings (OSTI)

... image, or RGB color image. cstack Stack of color (RGB) images. FRED (text) window; Dialog; (various) graphics windows.

453

Neutron imaging of alkali metal heat pipes  

Science Conference Proceedings (OSTI)

High-temperature heat pipes are two-phase, capillary driven heat transfer devices capable of passively providing high thermal fluxes. Such a device using a liquid-metal coolant can be used as a solution for successful thermal management on hypersonic flight vehicles. Imaging of the liquid-metal coolant inside will provide valuable information in characterizing the detailed heat and mass transport. Neutron imaging possesses an inherent advantage from the fact that neutrons penetrate the heat pipe metal walls with very little attenuation, but are significantly attenuated by the liquid metal contained inside. Using the BT-2 beam line at the National Institute of Standards and Technology (NIST) in Gaithersburg, Maryland, preliminary efforts have been conducted on a nickel-sodium heat pipe. The contrast between the attenuated beam and the background is calculated to be approximately 3%. This low contrast requires sacrifice in spatial or temporal resolution so efforts have since been concentrated on lithium (Li) which has a substantially larger neutron attenuation cross section. Using the CG-1D beam line at the High Flux Isotope Reactor (HFIR) of Oak Ridge National Laboratory (ORNL) in Oak Ridge, Tennessee, the first neutron images of high-temperature molybdenum (Mo)-Li heat pipes have been achieved. The relatively high neutron cross section of Li allows for the visualization of the Li working fluid inside the heat pipes. The evaporator region of a gravity assisted cylindrical heat pipe prototype 25 cm long was imaged from start-up to steady state operation up to approximately 900 C. In each corner of the square bore inside, the capillary action raises the Li meniscus above the bulk Li pool in the evaporator region. As the operational temperature changes, the meniscus shapes and the bulk meniscus height also changes. Furthermore, a three-dimensional tomographic image is also reconstructed from the total of 128 projection images taken 1.4o apart in which the Li had already cooled and solidified.

Kihm, Ken [University of Tennessee, Knoxville (UTK); Kirchoff, Eric [University of Tennessee, Knoxville (UTK); Golden, Matt [University of Tennessee, Knoxville (UTK); Rosenfeld, J. [Thermacore Inc.; Rawal, S. [Lockheed Martin Space Systems Company; Pratt, D. [United States Air Force Research Laboratory, Wright-Patterson Air Force Base; Bilheux, Hassina Z [ORNL; Walker, Lakeisha MH [ORNL; Voisin, Sophie [ORNL; Hussey, Dan [NIST Center for Neutron Research (NCRN), Gaithersburg, MD

2013-01-01T23:59:59.000Z

454

ON DARK PEAKS AND MISSING MASS: A WEAK-LENSING MASS RECONSTRUCTION OF THE MERGING CLUSTER SYSTEM A520 ,  

SciTech Connect

Merging clusters of galaxies are unique in their power to directly probe and place limits on the self-interaction cross-section of dark matter. Detailed observations of several merging clusters have shown the intracluster gas to be displaced from the centroids of dark matter and galaxy density by ram pressure, while the latter components are spatially coincident, consistent with collisionless dark matter. This has been used to place upper limits on the dark matter particle self-interaction cross-section of order 1 cm{sup 2} g{sup -1}. The cluster A520 has been seen as a possible exception. We revisit A520 presenting new Hubble Space Telescope Advanced Camera for Surveys mosaic images and a Magellan image set. We perform a detailed weak-lensing analysis and show that the weak-lensing mass measurements and morphologies of the core galaxy-filled structures are mostly in good agreement with previous works. There is, however, one significant difference: We do not detect the previously claimed 'dark core' that contains excess mass with no significant galaxy overdensity at the location of the X-ray plasma. This peak has been suggested to be indicative of a large self-interaction cross-section for dark matter (at least {approx}5{sigma} larger than the upper limit of 0.7 cm{sup 2} g{sup -1} determined by observations of the Bullet Cluster). We find no such indication and instead find that the mass distribution of A520, after subtraction of the X-ray plasma mass, is in good agreement with the luminosity distribution of the cluster galaxies. We conclude that A520 shows no evidence to contradict the collisionless dark matter scenario.

Clowe, Douglas [Department of Physics and Astronomy, Ohio University, 251B Clippinger Labs, Athens, OH 45701 (United States); Markevitch, Maxim [NASA Goddard Space Flight Center, Code 662, 8800 Greenbelt Road, Greenbelt, MD 20706 (United States); Bradac, Marusa [Department of Physics, University of California, One Shields Avenue, Davis, CA 95616 (United States); Gonzalez, Anthony H.; Chung, Sun Mi [Department of Astronomy, University of Florida, 211 Bryant Space Science Center, Gainesville, FL 32611 (United States); Massey, Richard [Department of Physics, Durham University, South Road, Durham DH1 3LE (United Kingdom); Zaritsky, Dennis, E-mail: clowe@ohio.edu [Steward Observatory, University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721 (United States)

2012-10-20T23:59:59.000Z

455

Exposing the dressed quark's mass  

E-Print Network (OSTI)

This snapshot of recent progress in hadron physics made in connection with QCD's Dyson-Schwinger equations includes: a perspective on confinement and dynamical chiral symmetry breaking (DCSB); a pre'cis on the physics of in-hadron condensates; results on the hadron spectrum, including dressed-quark-core masses for the nucleon and Delta, their first radial excitations, and the parity-partners of these states; an illustration of the impact of DCSB on the electromagnetic pion form factor, thereby exemplifying how data can be used to chart the momentum-dependence of the dressed-quark mass function; and a prediction that F_1^{p,d}/F_1^{p,u} passes through zero at Q^2\\approx 5m_N^2 owing to the presence of nonpointlike scalar and axial-vector diquark correlations in the nucleon.

Roberts, H L L; Cloet, I C; Roberts, C D

2010-01-01T23:59:59.000Z

456

Graphene, neutrino mass and oscillation  

E-Print Network (OSTI)

A resolution of the Abraham-Minkowski dilemma is presented that other constant velocities can play the role of c in the theory of relativity. For example, in 2005 electrons of graphene were discovered to behave as if the coefficient is a Fermi velocity. Then we propose a conjecture for neutrinos to avoid the contradiction among two-component theory, negative rest mass-square and oscillation.

Z. Y. Wang

2009-09-10T23:59:59.000Z

457

Polarization transfer NMR imaging  

DOE Patents (OSTI)

A nuclear magnetic resonance (NMR) image is obtained with spatial information modulated by chemical information. The modulation is obtained through polarization transfer from a first element representing the desired chemical, or functional, information, which is covalently bonded and spin-spin coupled with a second element effective to provide the imaging data. First and second rf pulses are provided at first and second frequencies for exciting the imaging and functional elements, with imaging gradients applied therebetween to spatially separate the nuclei response for imaging. The second rf pulse is applied at a time after the first pulse which is the inverse of the spin coupling constant to select the transfer element nuclei which are spin coupled to the functional element nuclei for imaging. In a particular application, compounds such as glucose, lactate, or lactose, can be labeled with .sup.13 C and metabolic processes involving the compounds can be imaged with the sensitivity of .sup.1 H and the selectivity of .sup.13 C.

Sillerud, Laurel O. (Los Alamos, NM); van Hulsteyn, David B. (Santa Fe, NM)

1990-01-01T23:59:59.000Z

458

Magnetic resonance imaging in Mexico  

Science Conference Proceedings (OSTI)

MR imaging has experienced an important growth worldwide and in particular in the USA and Japan. This imaging technique has also shown an important rise in the number of MR imagers in Mexico. However

A. O. Rodriguez; R. Rojas; F. A. Barrios

2001-01-01T23:59:59.000Z

459

12.141 Electron Microprobe Analysis by Wavelength Dispersive X-ray Spectrometry, January (IAP) 2006  

E-Print Network (OSTI)

Introduction to the theory of x-ray microanalysis through the electron microprobe including ZAF matrix corrections. Techniques to be discussed are wavelength and energy dispersive spectrometry, scanning backscattered ...

Chatterjee, Nilanjan

460

Ghost Imaging with Blackbody Radiation  

E-Print Network (OSTI)

We present a theoretical study of ghost imaging by using blackbody radiation source. A Gaussian thin lens equation for the ghost imaging, which depends on both paths, is derived. The dependences of the visibility and quality of the image on the transverse size and temperature of the blackbody are studied. The main differences between the ghost imaging by using the blackbody radiation and by using the entangled photon pairs are image-forming equation, and the visibility and quality of the image

Yangjian Cai; Shiyao Zhu

2004-07-29T23:59:59.000Z

Note: This page contains sample records for the topic "imaging 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

Scanning computed confocal imager  

DOE Patents (OSTI)

There is provided a confocal imager comprising a light source emitting a light, with a light modulator in optical communication with the light source for varying the spatial and temporal pattern of the light. A beam splitter receives the scanned light and direct the scanned light onto a target and pass light reflected from the target to a video capturing device for receiving the reflected light and transferring a digital image of the reflected light to a computer for creating a virtual aperture and outputting the digital image. In a transmissive mode of operation the invention omits the beam splitter means and captures light passed through the target.

George, John S. (Los Alamos, NM)

2000-03-14T23:59:59.000Z

462

Raman spectroscopic and mass spectrometric investigations of the hydrogen isotopes and isotopically labelled methane  

Science Conference Proceedings (OSTI)

Suitable analytical methods must be tested and developed for monitoring the individual process steps within the fuel cycle of a fusion reactor and for tritium accountability. The utility of laser-Raman spectroscopy accompanied by mass spectrometry with an Omegatron was investigated using the analysis of all hydrogen isotopes and isotopically labeled methanes as an example. The Omegatron is useful for analyzing all hydrogen isotopes mixed with the stable helium isotopes. The application of this mass spectrometer were demonstrated by analyzing mixtures of deuterated methanes. In addition, it was employed to study the radiochemical Witzbach exchange reaction between tritium and methanes. A laser-Raman spectrometer was designed for analysis of tritium-containing gases and was built from individual components. A tritium-compatible, metal-sealed Raman cuvette having windows with good optical properties and additional means for measuring the stray light was first used successfully in this work. The Raman spectra of the hydrogen isotopes were acquired in the pure rotation mode and in the rotation-vibration mode and were used for on. The deuterated methanes were measured by Raman spectroscopy, the wavenumbers determined were assigned to the corresponding vibrations, and the wavenumbers for the rotational fine-structure were summarized in tables. The fundamental Vibrations of the deuterated methanes produced Witzbach reactions were detected and assigned. The fundamental vibrations of the molecules were obtained with Raman spectroscopy for the first time in this work. The @-Raman spectrometer assembled is well suited for the analysis of tritium- containing gases and is practical in combination with mass spectrometry using an Omegatron, for studying gases used in fusion.

Jewett, J.R., Fluor Daniel Hanford

1997-02-24T23:59:59.000Z

463

Quantitative Imaging in Cell Biology  

E-Print Network (OSTI)

Quantitative! imaging! in! biology! is! concerned! with!Quantitative! imaging! in! biology! is! concerned! with!advances! in! cell! biology! by! enabling! the! tracking!

Yassif, Jaime

2012-01-01T23:59:59.000Z