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Separation science and technology. Semiannual progress report, October 1993--March 1994

Description: This document reports on the work done by the Separations Science and Technology Programs of the Chemical Technology Division, Argonne National Laboratory (ANL), in the period October 1993-March 1994. This effort is mainly concerned with developing the TRUEX process for removing and concentrating actinides from acidic waste streams contaminated with transuranic (TRU) elements. The objectives of TRUEX processing are to recover valuable TRU elements and to lower disposal costs for the nonTRU wast… more
Date: December 1, 1997
Creator: Vandegrift, G.F.; Aase, S.B. & Buchholz, B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Further improvement in the precision of 233U measurements by accelerator mass spectrometry at the Lawrence Livermore National Laboratory.

Description: In response to sponsor interest in October 2005 we proposed two methods for enhancing the precision of {sup 233}U accelerator mass spectrometry (AMS) capabilities at the Lawrence Livermore National Laboratory (LLNL). In a previous report we evaluated the first method and demonstrated that by increasing sample loading by a factor of four coupled with performing four replicates of each sample, we could achieve measurement precision of {approx}1%. Recent modifications to our system have enabled us… more
Date: February 4, 2008
Creator: Tumey, S. J.; Brown, T. A.; Hamilton, T. F. & Buchholz, B. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Using Biofuel Tracers to Study Alternative Combustion Regimes

Description: Interest in the use of alternative fuels and combustion regimes is increasing as the price of petroleum climbs. The inherently higher efficiency of Diesel engines has led to increased adoption of Diesels in Europe, capturing approximately 40% of the new passenger car market. Unfortunately, lower CO{sub 2} emissions are countered with higher nitrogen oxides (NOx) and particulate matter (PM) emissions, and higher noise. Noise and PM have traditionally been the obstacles toward consumer acceptance… more
Date: February 14, 2006
Creator: Mack, J. H.; Flowers, D. L.; Buchholz, B. A. & Dibble, R. W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Neuroscience and Accelerator Mass Spectrometry

Description: Accelerator mass spectrometry (AMS) is a mass spectrometric method for quantifying rare isotopes. It has had great impact in geochronology and archaeology and is now being applied in biomedicine. AMS measures radioisotopes such as {sup 3}H, {sup 14}C, {sup 26}Al, {sup 36}Cl and {sup 41}Ca, with zepto- or attomole sensitivity and high precision and throughput, enabling safe human pharmacokinetic studies involving: microgram doses, agents having low bioavailability, or toxicology studies where ad… more
Date: August 2, 2004
Creator: Palmblad, M. N.; Buchholz, B. A.; Hillegonds, D. J. & Vogel, J. S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Investigation of HCCI Combustion of Diethyl Ether and Ethanol Mixtures Using Carbon 14 Tracing and Numerical Simulations

Description: Despite the rapid combustion typically experienced in Homogeneous Charge Compression Ignition (HCCI), components in fuel mixtures do not ignite in unison or burn equally. In our experiments and modeling of blends of diethyl ether (DEE) and ethanol (EtOH), the DEE led combustion and proceeded further toward completion, as indicated by {sup 14}C isotope tracing. A numerical model of HCCI combustion of DEE and EtOH mixtures supports the isotopic findings. Although both approaches lacked informatio… more
Date: January 16, 2004
Creator: Mack, J. H.; Dibble, R. W.; Buchholz, B. A. & Flowers, D. L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Measuring the Effect of Fuel Structures and Blend Distribution on Diesel Emissions Using Isotope Tracing

Description: Carbon atoms occupying specific positions within fuel molecules can be labeled and followed in emissions. Renewable bio-derived fuels possess a natural uniform carbon-14 ({sup 14}C) tracer several orders of magnitude above petroleum-derived fuels. These fuels can be used to specify sources of carbon in particulate matter (PM) or other emissions. Differences in emissions from variations in the distribution of a fuel component within a blend can also be measured. Using Accelerator Mass Spectromet… more
Date: February 10, 2004
Creator: Cheng, A. S.; Mueller, C. J.; Buchholz, B. A. & Dibble, R. W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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A Numerical Investigation into the Anomalous Slight NOx Increase when Burning Biodiesel: A New (Old) Theory

Description: Biodiesel is a notable alternative to petroleum derived diesel fuel because it comes from natural domestic sources and thus reduces dependence on diminishing petroleum fuel from foreign sources, it likely lowers lifecycle greenhouse gas emissions, and it lowers an engine's emission of most pollutants as compared to petroleum derived diesel. However, the use of biodiesel often slightly increases a diesel engine's emission of smog forming nitrogen oxides (NO{sub x}) relative to petroleum diesel. … more
Date: January 30, 2007
Creator: Ban-Weiss, G. A.; Chen, J. Y.; Buchholz, B. A. & Dibble, R. W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Operating Experience and Teardown Analysis for Engines Operated on Biodiesel Blends (B20)

Description: In this study, eight engines and fuel systems were removed from trucks operating on B20 or diesel. Results indicate little difference in operational and maintenance costs between the B20- and diesel.
Date: November 1, 2005
Creator: Fraer, R.; Dinh, H.; Proc, K.; McCormick, R. L.; Chandler, K. & Buchholz, B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Retrospective Birth Dating of Cells

Description: The generation of cells in the human body has been difficult to study and our understanding of cell turnover is limited. Extensive testing of nuclear weapons resulted in a dramatic global increase in the levels of the isotope {sup 14}C in the atmosphere, followed by an exponential decrease after the test ban treaty in 1963. We show that the level of {sup 14}C in genomic DNA closely parallels atmospheric levels, and can be used to establish the time point when the DNA was synthesized and cells w… more
Date: April 19, 2005
Creator: L. Spalding, K.; Bhardwaj, R. D.; Buchholz, B. A.; Druid, H. & Frisen, J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Age estimation in forensic sciences: Application of combined aspartic acid racemization and radiocarbon analysis

Description: Age determination of unknown human bodies is important in the setting of a crime investigation or a mass disaster, since the age at death, birth date and year of death, as well as gender, can guide investigators to the correct identity among a large number of possible matches. Traditional morphological methods used by anthropologists to determine age are often imprecise, whereas chemical analysis of tooth dentin, such as aspartic acid racemization has shown reproducible and more precise results… more
Date: November 2, 2009
Creator: Alkass, K.; Buchholz, B. A.; Ohtani, S.; Yamamoto, T.; Druid, H. & Spalding, S. L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Magnetically Assisted Chemical Separation (MACS) Process : Preparation and Optimization of Particles for Removal of Transuranic Elements

Description: This report describes the development of a separation process for TRU elements from various high-level waste streams.
Date: September 1994
Creator: Nuñez, Luis; Kaminski, M.; Bradley, C.; Buchholz, B. A.; Landsberger, S.; Aase, S. B. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Measuring the Effect of Fuel Chemical Structure on Particulate and Gaseous Emissions using Isotope Tracing

Description: Using accelerator mass spectrometry (AMS), a technique initially developed for radiocarbon dating and recently applied to internal combustion engines, carbon atoms within specific fuel molecules can be labeled and followed in particulate or gaseous emissions. In addition to examining the effect of fuel chemical structure on emissions, the specific source of carbon for PM can be identified if an isotope label exists in the appropriate fuel source. Existing work has focused on diesel engines, but… more
Date: September 11, 2003
Creator: Buchholz, B. A.; Mueller, C. J.; Martin, G. C.; Upatnicks, A.; Dibble, R. W. & Cheng, S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Attomole detection of isotope-labeled compounds in chemical defense research

Description: AMS detects 14C at zeptomole to femtomole sensitivities. We detected the effect of ChE-blocking pyridostigmine bromide on the CNS uptake of a pyrethroid insecticide at scaled human-equivalent exposures in rats. Significant blood to brain protection from permethrin dosed at 5mg/kg is seen in the CNS of rats receiving pyridostigmine bromide pretreatments in chow at 2mg/kg/day. The synergy of these compounds was suggested as a precursor to some symptoms of `Gulf War Syndrome`.
Date: November 1, 1996
Creator: Vogel, J. S.; Buchholz, B. A.; Pawley, N. H.; Mauthe, R. E.; Dingley, K. & Turteltaub, K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Tips and Traps in the 14c Bio-AMS Preparation Laboratory (WSam 7)

Description: Maintaining a contamination free sample preparation lab for biological 14 C AMS requires the same or more diligence as a radiocarbon dating prep lab. Isotope ratios of materials routinely range over 4-8 orders of magnitude in a single experiment, dosing solutions contain thousands of DPM and gels used to separate proteins possess 14 C ratios of 1pMC. Radiocarbon contamination is a legacy of earlier tracer work in most biological laboratories, even if they were never hot labs. Removable surface … more
Date: October 12, 1999
Creator: Buchholz, B. A.; Haack, K. W.; Stewart, P. H. & Vogel, J. S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Using Carbon-14 Isotope Tracing to Investigate Molecular Structure Effects of the Oxygenate Dibutyl Maleate on Soot Emissions from a DI Diesel Engine

Description: The effect of oxygenate molecular structure on soot emissions from a DI diesel engine was examined using carbon-14 ({sup 14}C) isotope tracing. Carbon atoms in three distinct chemical structures within the diesel oxygenate dibutyl maleate (DBM) were labeled with {sup 14}C. The {sup 14}C from the labeled DBM was then detected in engine-out particulate matter (PM), in-cylinder deposits, and CO{sub 2} emissions using accelerator mass spectrometry (AMS). The results indicate that molecular structur… more
Date: January 7, 2004
Creator: Buchholz, B. A.; Mueller, C. J.; Upatnieks, A.; Martin, G. C.; Pitz, W. J. & Westbrook, C. K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Progress in alkaline peroxide dissolution of low-enriched uranium metal and silicide targets

Description: This paper reports recent progress on two alkaline peroxide dissolution processes: the dissolution of low-enriched uranium metal and silicide (U{sub 3}Si{sub 2}) targets. These processes are being developed to substitute low-enriched for high-enriched uranium in targets used for production of fission-product {sup 99}Mo. Issues that are addressed include (1) dissolution kinetics of silicide targets, (2) {sup 99}Mo lost during aluminum dissolution, (3) modeling of hydrogen peroxide consumption, (… more
Date: December 31, 1996
Creator: Chen, L.; Dong, D.; Buchholz, B. A.; Vandegrift, G. F. & Wu, D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Kinetics of Beta-14[14C] Carotene in a Human Subject Using Accelerator Mass Spectrometry

Description: {beta}-Carotene is a tetraterpenoid distributed widely throughout the plant kingdom. It is a member of a group of pigments referred to as carotenoids that have the distinction of serving as metabolic precursors to vitamin A in humans and many animals [1,2]. We used Accelerator Mass Spectrometry (AMS) [3] to determine the metabolic behavior of a physiologic oral dose of {beta}-[{sup 14}C]carotene (200 nanoCuries; 0.57 {micro}mol) in a healthy human subject. Serial blood specimens were collected … more
Date: January 31, 2000
Creator: Dueker, S. R.; Lin, Y.; Follett, J. R.; Clifford, A. J. & Buchholz, B. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Tracing Fuel Component Carbon in the Emissions from Diesel Engines

Description: The addition of oxygenates to diesel fuel can reduce particulate emissions, but the underlying chemical pathways for the reductions are not well understood. While measurements of particulate matter (PM), unburned hydrocarbons (HC), and carbon monoxide (CO) are routine, determining the contribution of carbon atoms in the original fuel molecules to the formation of these undesired exhaust emissions has proven difficult. Renewable bio-derived fuels (ethanol or bio-diesel) containing a universal di… more
Date: October 14, 2002
Creator: Buchholz, B. A.; Mueller, C. J.; Martin, G. C.; Cheng, A. S. E.; Dibble, R. W. & Frantz, B. R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Preventing and Removing Contamination in a Natural Radiocarbon Sample Preparation Laboratory

Description: The introduction of elevated {sup 14}C contamination into a natural radiocarbon sample preparation laboratory can occur through many different pathways. The most difficult to control is the introduction of contaminated samples from outside labs. Laboratories can remain {sup 14}C contaminated as a result of earlier tracer based research, even if ''hot'' work has not occurred in the laboratories in decades. Prior to accepting samples from outside collaborators, it is recommended that the collabor… more
Date: October 25, 2002
Creator: Zermeno, P.; Kurdyla, D. K.; Buchholz, B. A.; Heller, S. J.; Frantz, B. R.; Brown, T. A. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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