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Estimating thermal conductivity from core and well log data 总被引:1,自引:1,他引:0
The aim of the presented work was to introduce a method of estimating thermal conductivity using well log data. Many petrophysical properties of rocks can be determined both by laboratory measurements and well-logs. It is thus possible to apply geophysical data to empirical models based on relationships between laboratory measured parameters and derive continuous thermal conductivity values in well profiles. Laboratory measurements were conducted on 62 core samples of Meso-Paleozoic rocks from the Carpathian Foredeep. Mathematical models were derived using multiple regression and neural network methods. Geophysical data from a set of seven well logs: density, sonic, neutron, gamma ray, spectral gamma ray, caliper and resistivity were applied to the obtained models. Continuous thermal conductivity values were derived in three well profiles. Analysis of the obtained results shows good consistence between laboratory data and values predicted from well log data. 相似文献
64.
Boštjan Podkrajšek Gorazd Berčič Janja Turšič Irena Grgić 《Journal of Atmospheric Chemistry》2004,47(3):287-303
The reaction kinetics of S(IV) autoxidation catalyzed by Mn(II) in the pH range 3–5 typical for atmospheric liquid water,
was investigated. For reactions with pH maintained constant during the reaction course, the predictions obtained by a simple
integral approach cover kinetic results only for concentrations of HSO
3
−
up to 0.2 mM at pH 4.5. Thus, a generalized simple kinetic model, which can be used for predicting the reaction kinetics
in wider concentration, pH and temperature ranges, was derived. This model is based on the assumption that the reaction rate
is proportional to the concentration of a transient manganese-sulfito complex formed in the initial step of a radical chain
mechanism. In the proposed power law rate equation
the concentration of complex is calculated from the stability constant K and concentrations of reactants at a specific reaction time. This rate equation adequately predicts the reaction kinetics
in the pH range 3–5, in the concentration ranges 0.1 ≤ [HSO
3
−
] ≤ 0.4 mM and 2 ≤ [Mn(II)] ≤ 14.6 μM. For the temperature range 15–35 °C, the estimated value for activation energy is 92.0
± 0.1 kJ mol−1 and the Gibbs free energy of formation of the manganese-sulfito complex is −20.4 ± 0.3 kJ mol−1. Furthermore, the kinetics for catalytic reactions with pH maintained constant during the reaction course as well as with
initial pH adjusted only at the start of the reaction, is described satisfactorily by the present model. 相似文献
65.
Tom Kol Petr Dobrovolný Pter Szab Tom Mikita Tom Kyncl Josef Kyncl Irena Sochov Ale Flídr David Merta Michal Rybní
ek 《第四纪科学杂志》2022,37(1):123-132
The development of settlement and building activity is the result of socioeconomic, political and demographic changes in the past. However, accurate information on temporal variation in building activity is rather limited. Dendrochronological databases containing dated historical wooden constructions provide an important resource. We used 6514 tree-felling dates to reconstruct building activity in the Czech lands for the period 1450–1950. Comparing felling dates with historical events demonstrated that building activity was negatively associated with intense wars, particularly during the Thirty Years' War (1618–1648). After the Peace of Westphalia (1648), socioeconomic renewal and demographic growth were reflected in an upsurge of building activity, especially ecclesiastical buildings. While the construction of ecclesiastical and noble buildings culminated around the 1720s, rural buildings peaked in the 1780s and the 1820s. Although no direct effect of climate was demonstrated, adverse climatic conditions leading to harvest failures and subsequent famines (e.g. the ‘Hunger Years’ 1770–1772) significantly contributed to declines in building activity. In contrast, a higher number of felling dates were detected when strong and/or frequent windstorms occurred. This study provides a comprehensive understanding of building activity in Central Europe and advocates the use of dendrochronological databases for the investigation of human activities in history. 相似文献