ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 200 (1963), S. 564-565 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] This is quite acceptable, but does not indicate why Dr. Tilles cannot believe that a similar line of reasoning would be taken by any other explanation of the concentration of tritium in iron meteorites. One could say, for example, that only small amounts of tritium are found in the meteorites ...
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 208 (1965), S. 1053-1055 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] A SURVEY of the scientific literature reveals the fact that carbon-14 dates on bone often do not accord with independent estimates of the site ages. Bone dates are generally regarded as considerably less reliable than determinations using charcoal, wood, or other materials with large carbon ...
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 212 (1966), S. 489-492 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] THE use of naturally occurring radiocarbon as a means of investigating ground water movement has recently been developed1-*. When water enters the ground it inevitably carries a certain amount of carbon dioxide. The concentration greatly increases in the first few metres of soil due to removal ...
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 205 (1965), S. 1205-1207 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] Table 1. RADIOCARBON DATE PAIRS FROM THE INSTITUTO VENEZOLANO DE INVESTIGACIONES CIENTIFICAS USING THE BENZENE LIQUID SCINTILLATION METHOD The ages are calculated as years before 1950 A.D. a is the standard deviation Sample Sample IVIC-15; El Cerro snail shells IVIC-74; La Betania ...
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    Springer
    Surveys in geophysics 2 (1975), S. 217-239 
    ISSN: 1573-0956
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    Notes: Abstract Carbonate species, dissolved in appreciable quantities in all ground waters, can be extracted and used for radiocarbon dating. The material is mainly of biogenic origin, but contains some bicarbonate produced from limestone. This causes a dilution of the radiocarbon activity of the total carbonate species in the water and a correction is necessary in order to determine absolute radiocarbon ages, i.e., the time since the waters went underground. Three methods of evaluating the limestone contributions are examined critically: carbonate species ratios, carbon-13 variations, and concurrent tritium measurements. All possess uncertainties. The largest errors occur in the carbon-13 procedure, due to the wide natural fluctuation of the stable isotope content in plants and the occurrence of isotope effects in the soil air-water carbon dioxide exchange. Comparisons of the limestone dilution correction techniques show that they produce analogous results in actual aquifer studies, but with small differences in the calculated radiocarbon ages. The reasons for these inconsistencies have not yet been unequivocally established. Two problems are: the possibility of irreversible exchange of the ground water dissolved carbonate species with limestone in the aquifer matrix, and the significance of exchange of carbon dioxide in the water with that of the soil air in the surface layer of the catchment zone. Experiments are suggested that could resolve these questions.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    Publication Date: 1965-01-01
    Description: The I.V.I.C. laboratory started operation in December, 1963 using liquid scintillation techniques and the benzene method. The syntheses are carried out in a Packard benzene synthesizer and the solutions counted by a Packard automatic tri-carb spectrometer. For routine dating, a 4 cc counting vial is used with 2 cc benzene coming from the sample being dated and 2 cc commercial toluene added with the PPO and POPOP scintillators.
    Print ISSN: 0033-8222
    Electronic ISSN: 1945-5755
    Topics: Archaeology , Energy, Environment Protection, Nuclear Power Engineering , Geosciences
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    Publication Date: 1986-01-01
    Description: Sherds can be dated by four independent methods: 14C beta counting on associated material, accelerator mass spectrometry on carbon traces on and within the sherd, thermoluminescence studies on minerals within the sherd, and stylistic form. Age analyses of materials and sherds from several sites are shown in this work. Each technique has its own frequently encountered non-laboratory sources of error. A combination of at least two independent techniques is indispensable for the highest level of confidence.
    Print ISSN: 0033-8222
    Electronic ISSN: 1945-5755
    Topics: Archaeology , Energy, Environment Protection, Nuclear Power Engineering , Geosciences
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    Publication Date: 1964-01-01
    Description: The Radiocarbon Dating Laboratory of the University of Texas was reorganized in late 1962. The dates reported in this list were obtained from February to November, 1963. The laboratory uses liquid scintillation counting with benzene solutions (Tamers, Stipp, and Collier, 1961; Noakeset al., 1963). The chemical synthesis has been modified and improved in several ways in order to permit one worker to produce a sample per day.
    Print ISSN: 0033-8222
    Electronic ISSN: 1945-5755
    Topics: Archaeology , Energy, Environment Protection, Nuclear Power Engineering , Geosciences
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 9
    Publication Date: 1969-01-01
    Description: The laboratory renewed operations in January, 1968 after a year's inactivity due to the absence of the head, who was on leave at the University of Bonn. Synthesized benzene continues as the dating medium, but various improvements have been made on the chemical method in order to increase capacity. Combustions are no longer carried out for normal materials. Instead, charcoal samples are used directly (after the usual pretreatment) and wood, plants, cloth, etc. are carbonized in a nitrogen atmosphere. Charring is a considerably more rapid procedure than combustion since it eliminates the CO2 collection, carbonate precipitation, and filtration steps. The charcoal then is reacted with molten lithium metal. Also, it was found that carbonates are attacked directly by hot lithium to produce carbides and the preliminary generation of CO2 gas is not indispensable. The carbide, cooled to room temperature, is reacted with old water (IVIC-317, Radiocarbon, 1967, v. 9, p. 240), the acetylene separated from hydrogen in a double liquid nitrogen-cooled trap, and benzene produced with a chromium activated silica-alumina catalyst.
    Print ISSN: 0033-8222
    Electronic ISSN: 1945-5755
    Topics: Archaeology , Energy, Environment Protection, Nuclear Power Engineering , Geosciences
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 10
    Publication Date: 1970-01-01
    Description: The laboratory has been operating more than five years, supported entirely from Venezuelan government funds. Approximately 530 samples have been dated to the end of 1969. Of these, 40% are archaeologic specimens, the majority (141 samples) from Venezuela. Materials from most other countries of Latin America have been processed. The rest of the samples are from research programs of the Radiocarbon Laboratory itself. Thirty per cent of the total are measurements on carbonate species extracted from Venezuelan ground water aquifers.
    Print ISSN: 0033-8222
    Electronic ISSN: 1945-5755
    Topics: Archaeology , Energy, Environment Protection, Nuclear Power Engineering , Geosciences
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...