SVIBOR - Papers quoted in CC - project code: 1-07-064

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Papers quoted in Current Contents on project 1-07-064

Quoted papers: 21
Other papers: 56
Total: 77

Title:

Authors:: Chafetz, Henry; Srdoč, Dušan (44284); Horvatinčić, Nada (16101)

Journal: Geographie physique et Quaternaire
Number: 3
Volume: 48
Year: 1994
Pages: from 247 to 255
Number of references: 31
Language: engleski

Title:

Authors:: Krajcar Bronić, Ines (112976)

Journal: Nuclear Instruments and Methods in Physics Research B
ISSN: 0168-583x
Volume: 84
Year: 1994
Pages: from 300 to 302
Number of references: 17
Language: engleski
Summary: The mean energy required to form an ion pair (W value) and the Fano factor (F) are measured for 5.9 keV photons in isobutane-based tissue-equivalent gas. The measured values are: W = 25.1 +- 0.5 eV, and F = 0.25 +- 0.04. These values are in excellent agreement with the values for gas mixtures in which no appreciable energy transfer among gas components occurs (regular mixtures) calculated from the corresponding values for electrons in pure gas constituents, Wmix = 25.2 eV, and Fmix = 0.27, respectively.
Keywords: mean energy required to form an ion pair (W), the Fano factor (F), tissue-equivalent mixtures

Title:

Authors:: Krajcar Bronić, Ines (112976); Srdoč, Dušan (44284)

Journal: Radiation Research
ISSN: 0033-7587
Volume: 137
Year: 1994
Pages: from 18 to 24
Number of references: 37
Language: engleski
Summary: We calculated the mean energy required to produce an ion pair (W) in methane-, propane- and butane-based tissue-equivalent (TE) gas mixtures from W values in pure constituent gases according to various models for energy partition among gas components. We found an agreement between the experimental and calculated W values in the methane-based TE gas regardless of the model concept. In contrast, only those models which take into account differences in the stopping powers, total ionization cross sections and model constant of gas components give acceptable results for the propane-based TE gas. The calculated W value for high-energy electrons in the isobutane-based TE gas mixture is 25.2 eV for high-energy electrons and 28.0 eV for 5 MeV alpha particle.
Keywords: electron degradation, mean energy required to form an ion pair (W), gas mixtures, regular mixtures, tissue-equivalent mixtures, models for W calculation

Title:

Authors:: Obelić, Bogomil (33855); Horvatinčić, Nada (16101); Srdoč, Dušan (44284); Krajcar Bronić, Ines (112976); Sliepčević, Adica (43691); Grgić-Kapelj, Sanja

Journal: Radiocarbon
Number: 2
ISSN: 0033-8222
Volume: 36
Year: 1994
Pages: from 303 to 324
Number of references: 28
Language: engleski
Summary: Radiocarbon analyses made since our previous list (Srdoč & al., 1992) are presented. 216 dates of archaeological, geological and hydrogeological samples are given.
Keywords: C-14 dating, archaeology, geology, hydrogeology

Title:

Authors:: Srdoč, Dušan (44284); Osmond, J.; Horvatinčić, Nada (16101); Dabous, A.; Obelić, Bogomil (33855)

Journal: Radiocarbon
Number: 2
ISSN: 0033-8222
Volume: 36
Year: 1994
Pages: from 203 to 219
Language: engleski

Title:

Authors:: Krajcar Bronić, Ines (112976); Kimura, Mineo

Journal: Journal of Chemical Physics
Number: 16
ISSN: 0021-9606
Volume: 103
Year: 1995
Number of references: 17
Language: engleski
Summary: Electron thermalization in methane and argon-methane mixtures is studied by using the Boltzmann equation. The presence of low-lying vibrational excited states in methane significantly changes electron energy distribution functions and relaxation times. The thermalization time in mixtures of argon-methane (without vibrational states) smoothly changes as the mixture composition varies, and no significant difference in electron energy distribution functions is observed. When the vibrational excited states are taken into account, thermalization is almost completely defined by CH4, even at very low fractional concentrations of CH4.
Keywords: electron thermalization, electron energy distribution functions, Boltzmann equation, CH4, Ar - CH4 mixtures

Title:

Authors:: Krajcar Bronić, Ines (112976); Kimura, Mineo; Inokuti, Mitio

Journal: Journal of Chemical Physics
Number: 16
ISSN: 0021-9606
Volume: 102
Year: 1995
Pages: from 6552 to 6558
Number of references: 20
Language: engleski
Summary: Time-dependent and temperature-dependent aspects of the thermalization of electrons in atomic gases are studied by using the Boltzmann equation. H, Ar, and Cs gases were chosen for the present study because of the characteristic and significantly different dependences of their momentum transfer cross sections on electron energy. The effects of the cross section shapes on electron distribuiton functions and degradation spectra are examined.
Keywords: electron thermalization, electron energy distribution function, Boltzmann equation, atomic gases, degradation spectra

Title:

Authors:: Krajcar Bronić, Ines (112976)

Journal: Radiation Protection and Dosimetry
Number: 1-3
ISSN: 0144-8420
Volume: 61
Year: 1995
Number of references: 10
Language: engleski
Summary: The mean gas amplification factor, the single electron spectra, the mean energy required to form an ion pair (W), and the energy resolution were measured in argon-isobutane mixtures at various pressures over wide range of the reduced electric field strengths in a cylindrical proportional counter. In mixtures with low isobutane partial pressure, gas gain is an over-exponential function of the applied high voltage. The relative variance of single electron spectra, the apparent W value and the energy resolution are functions of both gas gain and isobutane partial pressure in the mixture. A better energy resolution is obtained with mixtures containing less isobutane at low gas gains whereas at the higher gas gains usually applied in X ray spectroscopy the resolution is degraded.
Keywords: mean energy required to form an ion pair (W), single electron spectra, energy resolution, gas mixtures, Ar - isobutane mixture

Title:

Authors:: Horvatinčić, Nada (16101); Obelić, Bogomil (33855); Krajcar Bronić, Ines (112976); Srdoč, Dušan (44284); Bistrović, Romana

Journal: Radiocarbon
Number: 3
ISSN: 0033-8222
Volume: 37
Year: 1995
Number of references: 12
Language: engleski
Summary: We investigated the effect of radon (Rn-222) contamination of samples and chemicals used for sample preparation and gas purification on the C-14 age of samples. Radon countrate was monitored over several Rn half-lives in a proportional counter filled with methane. We analyzed approx. 240 samples of fossil and recent wood, charcoal, bone, dissolved inorganica carbon in water, travertine, peat, aquatic plants, organic soil and atmospheric CO2 for Rn contamination. Chemicals used for gas purification (MnO2, Mg(ClO4)2), ruthenium coated pellets used for catalytic reduction of CO2 to CH4, and acids used for dissolution of calcaraeous samples (HCl and H3PO4) are also potential sources of radon. Most geological samples contained a significant amount of radon, as opposed to samples of wood, cahrcoal, aquatic plants and atmospheric CO2. We also studied radon contamination of wazter samples during tritium activity measurements in a CH4-filled gas proportional counter. An increased countrate was found in H-3 channel, as well as above 20 keV region in radon contaminated groundwater samples.
Keywords: radiocarbon measurements, contamination, radon

Title:

Authors:: Krajcar Bronić, Ines (112976); Horvatinčić, Nada (16101); Obelić, Bogomil (33855); Bistrović, Romana

Journal: Radiocarbon
Number: 3
ISSN: 0033-8222
Volume: 37
Year: 1995
Number of references: 8
Language: engleski
Summary: The Radiocarbon and Tritium Laboratory at the Rudjer Bošković Institute participated in all three radiocarbon intercomparison studies. The first International Collaborative Study (ICS) showed that the age of organic samples measured at out laboratory is ca. 70 yr younger than the median ICS value. After introducing a slight modification in our chemical pretreatment procedure by acidifying samples after alkaline treatment, we obtained excellent agreement between our results and the median values reported by two subsequent intercomparisons (IAEA, TIRI) without any laboratory bias.
Keywords: C-14 dating, intercomparison

Title:

Authors:: Obelić, Bogomil (33855); Šmalcelj, Marija; Horvatinčić, Nada (16101); Bistrović, Romana; Sliepčević, Adica (43691)

Journal: Radiocarbon
Number: 3
ISSN: 0033-8222
Volume: 37
Year: 1995
Language: engleski
Summary: During the 1989-1994 renovation of the Zagreb Town Museum, it became obvious that the area was inhabited in prehistoric times. We C-14 dated 40 samples to determine various settlement periods. The ages of the sample span a much longer time than expected, from the Early Iron Age (Hallstatt period) to the 19th century AD. C-14 dates on charcoal samples placed the remains of dwelling pits to the Hallstatt period, 8th to 4th century BC. A late La Tene settlement dated between the 4th century BC and the 2nd century AD. Medieval fortifications were identified in the western part of the complex, consisting of a well-preserved wooden structure used for construction of the royal castrum. C-14 measurements on wooden planks and posts date the construction of the fortification between the 13th and 15th centuries and branches, beams, and tools found below the basement of the Convent of St.Clare span the 16th to the 19th century AD.
Keywords: radiocarbon dating, Hallstatt, La Tene, Middle Ages, Zagreb


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