Zeitschrift für Naturforschung / A / 30 (1975)
نویسندگان
چکیده
The range of the radiocarbon dating method can be extended by about 20,000 years by means of thermal diffusion isotopic enrichment. A description of the Clusius-Dickel type enrichment columns and their operation is given. Prior to enrichment the carbonaceous sample material is combusted to C0 2 and then reduced to CO. The enriched sample is re-oxidized to C0 2 . The combustion-, reductionand oxidation-apparatus and their operation are described. The performance of the thermal diffusion columns has been tested and an empirical, volume independent relation between the isotope separation factors of 14C160 and all molecules with mass (30 ) is given g 1 4 l = (1.13 ±0.05) (<? 3 0 l ) + (0.035 ±0.005) ( g 3 0 l ) 2 .
منابع مشابه
Zeitschrift für Naturforschung / C / 30 (1975)
The complexation of cadmium by isocitrate has been studied at 25 °C and pH 7.5 in a range of ionic strength from 0.01 to 0j16. The formation constant of the complex between cadmium and tribasic isocitrate varies from 860 M-1 at ^ = 0 .1 6 to approximately 24,500 M -1 at infinite dilu tion. These data allow the distribution of the chemical forms of cadmium added to the incubation mixtures for t...
متن کاملZeitschrift für Naturforschung / C / 38 (1983)
On 01.01.2015 it is planned to change the License Conditions (the removal of the Creative Commons License condition “no derivative works”). This is to allow reuse in the area of future scientific usage. Dieses Werk wurde im Jahr 2013 vom Verlag Zeitschrift für Naturforschung in Zusammenarbeit mit der Max-Planck-Gesellschaft zur Förderung der Wissenschaften e.V. digitalisiert und unter folgender...
متن کاملStress-induced changes in cell titer of crayfish hemolymph.
Cell titer in peripheral hemolymph of crayfishes rises in less than one hour after administration of stress. The stress may be wounding or handling of the animals.
متن کاملThe effect of calcium and phosphate on the biphasic calcium uptake by the sarcoplasmic reticulum.
The amplitude of the fast uptake and the initial rate of the slow uptake increase with increasing free calcium concentrations, up to 30 muM. In that range, both processes are correlated to each other. At higher concentrations, the slow uptake is more inhibited than the fast uptake. The fast uptake shows a maximum amplitude which remains unchanged in the presence of phosphate. The slow uptake le...
متن کامل