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Primordial Organic Chemistry. I. Compounds Resulting from Electron Irradiation of C<sup>14</sup>H<sub>4</sub>

Description: C{sup 14}-labeled methane, together with a number of other presumed primordial gases of the earth's atmosphere, has been subjected to electron bombardments. The products formed have been examined by paper chromatography, ion exchange chromatography, mass spectrometry, and ultraviolet light spectrophotometry. A number of minor molecules have been specifically identified, and urea has been found as a major component in the absence of added phosphine; the formation of urea is inhibited by added phosphine. Most of the products can be accounted for as discrete molecules, even though they are as yet unidentified.
Date: December 1, 1961
Creator: Palm, Christopher & Calvin, Melvin
Partner: UNT Libraries Government Documents Department

Transport Models for Radioactive Carbon Dioxide at RWMC

Description: Radioactive carbon dioxide (formed by oxidation of carbon-14) is a highly mobile, radioactive contaminant released from solid wastes buried at the Subsurface Disposal Area (SDA) at the Radioactive Waste Management Complex (RWMC) at the Idaho National Engineering and Environmental Laboratory (INEEL). Radioactive CO2 is chemically active in the environment, volatile, water soluble, and subject to adsorption on solids. For this reason, its fate must be understood and controlled to meet radiological requirements (protection of the atmosphere, aquifer, vadose zones, plants and animals). In the present work, the migration of carbon-14 as dissolved bicarbonate was studied using miscible displacement experiments in water-saturated columns containing sediments from RWMC. Dissolved carbon-14 was retarded relative to the movement of water by a factor of about 3.6, which translates to a partition coefficient (Kd) of 0.8 ml/g. Two different adsorption sites were identified, with one site possibly having a nonlinear adsorption isotherm. A conservative tracer gas, sulfur hexafluoride, was used to measure the tortuosity of sedimentary material for gaseous diffusion. The tortuosity of the RWMC sediment (Spreading Area B sediment) was determined to be 3.2, which is slightly greater than predicted by the commonly used Millington-Quirk equation. In terms of affecting the migration of carbon-14 to the aquifer, the relative importance of the parameters studied is: (1) natural moisture content of the sediments, (2) sediment tortuosity to gas-phase diffusion, and (3) adsorption onto solid phases.
Date: December 1, 2001
Creator: Hull, Laurence Charles & Hohorst, Frederick August
Partner: UNT Libraries Government Documents Department

Influence of Other Contaminants on Natural Attenuation of Chlorinated Solvents

Description: Studies at numerous sites have shown high variability in the degradation rates of chlorinated solvents as measured by microcosm studies with <sup>14</sup>C labeled contaminants. The ability of nutrient and carbon additions to stimulate degradation can vary widely. Although some of these variations can be related to the structure of the extant microbial community, the presence of other less refractory contaminants may be critical fctors impacting the rate of chlorocarbon mineralization. Relaatively highe rates of TCE degradation have been observed in the DOE K-25 burial grounds with diverse organic loadings as well as in areas that show evidence for hydrocarbon contamination. Similarly, at other sites where there was TCE in the absence of hydrocarbons or other contaminants, the measured degradation rates have often been found to be very low. At various other sites, the intrasite variability in degradation rates appeared to be related to the presence of hydrocarbon contamination. The highest rates were observed at sites with evidence of hydrocarbons. These observations indicated that the viability of natural attenuation as a remediation option for chlorinated solvents might depend in part on the presence co-contaminants such as hydrocarbons or natural matter.
Date: April 19, 1999
Creator: Kinsall, B.L.; Palumbo, A.V.; Pfiffner, S.M.; Phelps, T.J. & Salpas, P.
Partner: UNT Libraries Government Documents Department

14CO2 INCORPORATION INTO THE NUCLEIC ACIDS OF SYNCHRONOUSLYGROWING CHLORELLA CELLS

Description: A study of the incorporation of {sup 14}CO{sub 2} into cell components of synchronously growing Chlorella pyrenoidosa has shown that DNA is synthesized primarily during the latter stages of the cell cycle prior to cell division. RNA was synthesized at an approximately equal rate during each of the three phases of the cell growth studied. No major differences were noted in the incorporation of {sup 14}CO{sub 2} into the soluble cell components in these long-term incorporation studies.
Date: March 8, 1962
Creator: Stange, Luise; Kirk, Martha; Bennett, Edward L. & Calvin, M.
Partner: UNT Libraries Government Documents Department

An Isotope Effect in Photosynthesis

Description: In the course of some kinetic studies on photosynthesis of barley seedlings, it has been found that plants utilize C{sup 12}O{sub 2} faster than C{sup 14}O{sub 2}. The plants were placed in a closed system containing an infra-red absorption-cell for the analysis of total CO{sub 2} and an ionization chamber for the determination of C{sup 14}O{sub 2} in the gas phase, both instruments recording continuously. Carbon dioxide, containing about 2% C{sup 14}O{sub 2}, was introduced in the dark and the specific activity at this point taken as unity. After a short dark period, the lights were turned on and photosynthesis was allowed to take place. A figure shows the result of a typical experiment. During the initial dark period the specific activity fell because of dilution by inactive respired CO{sub 2}. However, as photosynthesis proceeded, the specific activity of the residual CO{sub 2} rose until, when only 1/6 of it remained, the specific activity reached a peak some 20% higher than it had been at the start of photosynthesis. At this point the steady respiratory dilution became an appreciable fraction of the total remaining CO{sub 2}, and the specific activity dropped rapidly.
Date: November 23, 1948
Creator: Weigl, J.W. & Calvin, M.
Partner: UNT Libraries Government Documents Department

The Relationship Between the Metabolic Pools of Photosynthetic andRespiratory Intermediates

Description: Using radioactive carbon dioxide, an attempt has been made to distinguish the various pools of intermediary metabolism which may be physically or chemically separate within the cell. Some correlation between the structural elements of the cells and these pools appears possible.
Date: July 1, 1958
Creator: Moses, V.; Calvin, M.; Holm-Hansen, O. & Bassham, J.A.
Partner: UNT Libraries Government Documents Department

The Path of Carbon in Photosynthesis IX. Photosynthesis,Photoreduction and the Hydrogen-Oxygen-Carbon Dioxide Dark Reaction

Description: A comparison of the rates of fixation of Carbon 14 dioxide in algae for the processes of photosynthesis, photoreduction and the hydrogen-oxygen-carbon dioxide dark reaction has been made. For the same series of experiments, rates of incorporation of tracer carbon into the separate soluble components using the radiogram method have been determined. The mechanism of carbon dioxide uptake has been shown to occur via two distinct paths. In all cases studied, essentially the same compounds appear radioactive. The distribution with time, however, differs markedly.
Date: February 1, 1950
Creator: Badin, Elmer J. & Calvin, Melvin
Partner: UNT Libraries Government Documents Department

Carbon Dioxide Fixation by Green Plants

Description: Since the end of the war when the long-lived isotope of carbon, C{sup 14} became available a new tool has been applied in the study of photosynthesis. Because of the interest evoked by the tracer method, research in all areas of photosynthesis has expanded. There have been reviews on various aspects of photosynthesis such as the primary photochemical reaction, quantum efficiency products, and comparative biochemistry, many discussions of which were included in the monograph of The American Society of Plant Physiologists, ''Photosynthesis in Plants''.
Date: January 3, 1950
Creator: Benson, A.A. & Calvin, M.
Partner: UNT Libraries Government Documents Department

Human folate metabolism using 14C-accelerator mass spectrometry

Description: Folate is a water soluble vitamin required for optimal health, growth and development. It occurs naturally in various states of oxidation of the pteridine ring and with varying lengths to its glutamate chain. Folates function as one-carbon donors through methyl transferase catalyzed reactions. Low-folate diets, especially by those with suboptimal methyltransferase activity, are associated with increased risk of neural tube birth defects in children, hyperhomocysteinemic heart disease, and cancer in adults. Rapidly dividing (neoplastic) cells have a high folate need for DNA synthesis. Chemical analogs of folate (antifolates) that interfere with folate metabolism are used as therapeutic agents in cancer treatment. Although much is known about folate chemistry, metabolism of this vitamin in vivo in humans is not well understood. Since folate levels in blood and tissues are very low and methods to measure them are inadequate, the few previous studies that have examined folate metabolism used large doses of radiolabeled folic acid in patients with Hodgkin�s disease and cancer (Butterworth et al. 1969, Krumdieck et al. 1978). A subsequent protocol using deuterated folic acid was also insufficiently sensitive to trace a physiologic folate dose (Stites et al. 1997). Accelerator mass spectrometry (AMS) is an emerging bioanalytical tool that overcomes the limitations of traditional mass spectrometry and of decay counting of long lived radioisotopes (Vogel et al. 1995). AMS can detect attomolar concentrations of 14 C in milligram-sized samples enabling in vivo radiotracer studies in healthy humans. We used AMS to study the metabolism of a physiologic 80 nmol oral dose of 14 C-folic acid (1/6 US RDA) by measuring the 14 C-folate levels in serial plasma, urine and feces samples taken over a 150-day period after dosing a healthy adult volunteer.
Date: March 25, 1999
Creator: Arjomand, A; Bucholz, B A; Clifford, A J; Duecker, S R; Johnson, H; Schneider, P D et al.
Partner: UNT Libraries Government Documents Department

14C dating of bone using (gamma) Carboxyglutamic Acid and Carboxyglycine (Aminomalonate)

Description: Radiocarbon determinations have been obtained on {gamma}-carboxyglutamic acid [Gla] and {alpha}-carboxyglycine (aminomalonate) [Am] as well as acid- and base-hydrolyzed total amino acids isolated from a series of fossil bones. As far as they are aware, Am has not been reported previously in fossil bone and neither Gla nor Am {sup 14}C values have been measured previously. Interest in Gla, an amino acid found in the non-collagen proteins osteocalcin and matrix Gla-protein (MGP), proceeds from the suggestion that it may be preferentially retained and more resistant to diagenetic contamination affecting {sup 14}C values in bones exhibiting low and trace amounts of collagen. The data do not support these suggestions. The suite of bones examined showed a general tendency for total amino acid and Gla concentrations to decrease in concert. Even for bones retaining significant amounts of collagen, Gla (and Am extracts) can yield {sup 14}C values discordant with their expected age and with {sup 14}C values obtained on total amino-acid fractions isolated from the same bone sample.
Date: April 27, 1999
Creator: Southon, J R; Burky, R T; Kirner, D L; Taylor, R E & Hare, P E
Partner: UNT Libraries Government Documents Department

Radiocarbon dating organic residues at the microgram level

Description: Relation between submilligram sample size and {sup 14}C activity for sample blanks (wood from Pliocene sediments) and a contemporary standard (oxalic acid) for catalytically reduced graphitic carbon was examined down to 20 micrograms. Mean age of the 1 mg wood sample blanks is now about 51.3 ka (0.168 pMC) while the mean for 20 microgram sample blanks is about 42.9 ka. So far, the lowest value for a 1-mg wood sample blank is about 60.5 ka (0.056 pMC). We have determined a mean {sup 14}C age of about 9.4 ka from a suite of 7 organic extracts from hair, bone, and matting from a mummified human skeleton from Spirit Cave, Nevada. These data indicate that the Spirit Cave human is the third, oldest directly-dated, human skeleton currently known from North America.
Date: January 1, 1997
Creator: Kirner, D. L.; Burky, R.; Taylor, R. E. & Southon, J. R.
Partner: UNT Libraries Government Documents Department

Fuel age impacts on gaseous fission product capture during separations

Description: As a result of fuel reprocessing, volatile radionuclides will be released from the facility stack if no processes are put in place to remove them. The radionuclides that are of concern in this document are 3H, 14C, 85Kr, and 129 Rosnick 2007 I. The question we attempt to answer is how efficient must this removal process be for each of these radionuclides? To answer this question, we examine the three regulations that may impact the degree to which these radionuclides must be reduced before process gases can be released from the facility. These regulations are 40 CFR 61 (EPA 2010a), 40 CFR 190(EPA 2010b), and 10 CFR 20 (NRC 2012), and they apply to the total radonuclide release and to the dose to a particular organ – the thyroid. Because these doses can be divided amongst all the radionuclides in different ways and even within the four radionuclides in question, several cases are studied. These cases consider for the four analyzed radionuclides inventories produced for three fuel types—pressurized water reactor uranium oxide (PWR UOX), pressurized water reactor mixed oxide (PWR MOX), and advanced high-temperature gascooled reactor (AHTGR)—several burnup values and time out of reactor extending to 200 y. Doses to the maximum exposed individual (MEI) are calculated with the EPA code CAP-88 ( , 1992). Two dose cases are considered. The first case, perhaps unrealistic, assumes that all of the allowable dose is assigned to the volatile radionuclides. In lieu of this, for the second case a value of 10% of the allowable dose is arbitrarily selected to be assigned to the volatile radionuclides. The required decontamination factors (DFs) are calculated for both of these cases, including the case for the thyroid dose for which 14C and 129I are the main contributors. However, for completeness, for one fuel type and ...
Date: September 21, 2012
Creator: Jubin, Robert T.; Soelberg, Nicolas R.; Strachan, Denis M. & Ilas, G.
Partner: UNT Libraries Government Documents Department

NON-DESTRUCTIVE RADIOCARBON DATING: NATURALLY MUMMIFIED INFANT BUNDLE FROM SW TEXAS

Description: Plasma oxidation was used to obtain radiocarbon dates on six different materials from a naturally mummified baby bundle from the Lower Pecos River region of southwest Texas. This bundle was selected because it was thought to represent a single event and would illustrate the accuracy and precision of the plasma oxidation method. Five of the materials were clearly components of the original bundle with 13 dates combined to yield a weighted average of 2135 {+-} 11 B.P. Six dates from a wooden stick of Desert Ash averaged 939 {+-} 14 B.P., indicating that this artifact was not part of the original burial. Plasma oxidation is shown to be a virtually non-destructive alternative to combustion. Because only sub-milligram amounts of material are removed from an artifact over its exposed surface, no visible change in fragile materials has been observed, even under magnification. The method is best applied when natural organic contamination is unlikely and serious consideration of this issue is needed in all cases. If organic contamination is present, it will have to be removed before plasma oxidation to obtain accurate radiocarbon dates.
Date: September 7, 2004
Creator: Steelman, K L; Rowe, M W; Turpin, S A; Guilderson, T P & Nightengale, L
Partner: UNT Libraries Government Documents Department

Radiocarbon dating of ancient rock paintings

Description: This report presents progress made on a technique for {sup 14}C dating pictographs. A low-temperature oxygen plasma is used coupled with high-vacuum technologies to selectively remove C-containing material in the paints without contamination from inorganic carbon from rock substrates or accretions.
Date: June 20, 1995
Creator: Ilger, W.A.; Hyman, M.; Rowe, M.W. & Southon, J.
Partner: UNT Libraries Government Documents Department

Isotope tracers of organic carbon during artificial recharge

Description: This project developed an analytical technique for measuring the isotope abundance for 14C and 13C in total organic carbon (TOC) in order to test whether these measurements can trace TOC interaction with sedimentary material at the bottom of rivers and lakes, soils, and subsurface aquifer rocks.
Date: February 9, 1998
Creator: Davisson, M.L.
Partner: UNT Libraries Government Documents Department

Age validation of canary rockfish (Sebastes pinniger) using two independent otolith techniques: lead-radium and bomb radiocarbon dating.

Description: Canary rockfish (Sebastes pinniger) have long been an important part of recreational and commercial rockfish fishing from southeast Alaska to southern California, but localized stock abundances have declined considerably. Based on age estimates from otoliths and other structures, lifespan estimates vary from about 20 years to over 80 years. For the purpose of monitoring stocks, age composition is routinely estimated by counting growth zones in otoliths; however, age estimation procedures and lifespan estimates remain largely unvalidated. Typical age validation techniques have limited application for canary rockfish because they are deep dwelling and may be long lived. In this study, the unaged otolith of the pair from fish aged at the Department of Fisheries and Oceans Canada was used in one of two age validation techniques: (1) lead-radium dating and (2) bomb radiocarbon ({sup 14}C) dating. Age estimate accuracy and the validity of age estimation procedures were validated based on the results from each technique. Lead-radium dating proved successful in determining a minimum estimate of lifespan was 53 years and provided support for age estimation procedures up to about 50-60 years. These findings were further supported by {Delta}{sup 14}C data, which indicated a minimum estimate of lifespan was 44 {+-} 3 years. Both techniques validate, to differing degrees, age estimation procedures and provide support for inferring that canary rockfish can live more than 80 years.
Date: November 4, 2007
Creator: Andrews, A H; Kerr, L A; Cailliet, G M; Brown, T A; Lundstrom, C C & Stanley, R D
Partner: UNT Libraries Government Documents Department

IDENTIFICATION OF HYDROCARBON TYPES IN "ULTRASENE"

Description: The C/sup 1//sup 1/-C/sup 1//sup 4/ components of a sample of"Ultrasene" were identified as normal- and iso-paraffins; mono-, bi-, and tri-cycloparaffins; alkylbenzenes; indans; indenes; naphthalenes; and acenaphthenes. The aromatic content of this sample was 3.0 vol%. (auth)
Date: April 1, 1961
Creator: Wilhite, R. N.
Partner: UNT Libraries Government Documents Department