To assess the historical and sociological significance of the cold fusion saga, researchers need accurate information about the dates of various events associated with the saga. Based on materials in the Cornell Cold Fusion Archive, this article provides both a chronology and citations to documentary evidence for cold fusion events from 1926 to the end of 1990.
Principles of the thorium-230 dating method were applied to the study of thorium and uranium isotopes in a series of rain samples collected at Fayetteville (36°N, 94°W), Arkansas, since 1980. The results indicate that the rainwater contains volcanic ash materials with a wide variety of ages, which were blown up onto the upper stratosphere from the 18 May 1980 eruption of Mount St. Helens and the 28 March 1982 eruption of E1 Chichón. These volcanic materials seem to have stayed airborne for a number of years and profoundly affected the global atmospheric inventories of thorium and uranium isotopes.
The relative activities of the members of the principal radioactive families, with respect to the initial activities of chosen
parents were calculated for a wide range of time intervals. Tables and graphs that are useful for radiochemistry, source standardization
and chronology are presented.
Neutron activation, applied to silver and copper based coinage, leads to a measure of the mean concentrations of major and 12 trace elements, even if their distribution is heterogeneous. The drawbacks of this activation method applied to such a matrix are shielding effects and high radioactivity of major elements. Both effects were avoided by accurately calculating the correction coefficients and by choosing the optimal working conditions. Analytical results obtained lead to a better knowledge of the chronology and origin of Armorican protohistorical coinage.
Authors:Y. Hayashi, N. Ikeue, K. Tanoi, N. Nogawa, T. Tange, H. Yagi, K. Matsune, and T. Nakanishi
We have analyzed 16 elements and the radioactivity of 210Pb in a wood disk, across the annual rings to find out a promising tool for dendrochronology (chronology of wood) both for a Japanese wood, Cryptomeria japonica, and for an Indonesian rain forest wood, Alstonia, which does not form annual rings because of the relatively constant climate of the rain forest. As a result, only Mg concentration showed similar, smooth decreasing tendency in both wood species. The smooth change of the Mg concentration across the annual rings along with the growth suggested the possibility of the Mg concentration determination as a promising dendrochronological tool.
Historical records of short lived (140Ba, 131I, 103Ru and 95Zr+95Nb) and long-lived (137Cs and 90Sr) fission products by fallout measurements performed in Argentina since 1959 were analyzed in order to define the main characteristics of 137Cs fallout time evolution in the Nahuel Huapi National Park, Patagonia, Argentina. Sedimentary cores were sampled from Lake Nahuel Huapi and Lake Morenito, which are located within Nahuel Huapi National Park. 137Cs specific activity profiles were measured and 210Pb dating was performed in each core. The time evolution of 137Cs fallout shows different characteristics than records taken in the Northern Hemisphere.137Cs specific activity profiles of the cores studied reproduce the fallout time sequence observed in the historical records, and the chronology obtained shows excellent agreement with 210Pb dating.
The environmental contamination of transuranics following the Palomares accident in 1966 (Southern Spain) has been continuous monitored on land and scientific programs are still running. The study of the land to sea transfer of the contamination started in 1986, focussed on the depositional history recorded in marine sediments. At the continental shelf, south of the mouth of the Almanzora river, enhanced levels of plutonium and americium were found which could be related to the accident. Additional analysis of marine sediments, collected far from the impact point, showed the presence of a hot particle. The study of the chronology of this sediment core and the isotopic ratios are given in this paper to assess the origin and pathway of the particle. The route of this particle was found to be the aerial transfer at the time of the accident.
Authors:R. Singhal, M. Venkatesh, D. Wagh, H. Basu, T. Chavan, M. Pimple, and A. Reddy
Downcore variation of trace metals in sediment cores along the coastal line is one of the markers to assess the intrusion
of industrial pollutants into the aquatic environment. Fifty sediment core samples from the Mumbai Harbour Bay (MHB), were
studied for the trace element content. MHB is a recipient of effluents from different industries situated all along its coast
around Thane–Belapur region. The average concentrations of Titanium (Ti), Manganese (Mn), Iron (Fe), Nickel (Ni), Copper (Cu),
Zinc (Zn) were determined by inductively coupled plasma-optical emission spectroscopy and complemented by analysing with energy
dispersive X-ray fluorescence spectrometry. In addition to this, depth profiles of K and Ca were also studied to assess the
homogeneity of the geological strata of the region. Trace metals such as Cu, Ni and Zn show enrichment between 16 to 28 cm,
whereas, uniform distribution through out the core was observed for K, Ca, Ti, Mn and Fe. Chronology of the heavy metal deposition
was predicated based on the average sedimentation rate (0.92 ± 0.08 cm year−1) derived using depth-wise 137Cs concentration profile in core of bottom sediment. The results of the analysis showed that MHB had received excess inputs
of Cu, Ni and Zn in the year 1981, 1988 and 1982, respectively. Surface concentration of Cu, Ni, Zn and Fe compared to the
reference site indicates moderate pollution in the recent years whereas for elements K, Ca, Ti and Mn, the values are normal
indicating MHB unpolluted for the latter elements.
Authors:P. Mitchell, W. Schell, A. McGarry, T. Ryan, J. Sanchez-Cabeza, and A. Vidal-Quadras
Six peat cores taken from three unmodified blanket and raised bogs in Ireland were sectioned and analyzed for a range of radionuclides including134Cs,137Cs,238Pu,239Pu,241Am, and210Pb.134Cs and137Cs were measured by high resolution gamma-spectrometry, while the transuranium nuclides were determined after chemical separation by alpha-spectrometry.241Pu, present on the electroplated discs together with Pu(), was measured directly by low-level liquid scintillation counting. Core chronologies were established by measuring the unsupported210Pb component using low energy photon spectrometry (LEPS). From the resulting profiles, relaxation depths and migration rates for the above mentioned radionuclides have been determined and differences in the values of these parameters interpreted.238Pu/239,240Pu and241Pu/239,240Pu ratios have been examined carefully and are discussed in some detail. Finally, the contribution from Chernobyl to the total radiocaesium inventory in each core has been established using the134Cs/137Cs ratio observed in the initial fallout from Chernobyl.