Geosciences and Engineering

Symbols used on ethnic maps in the early decades of the 20th century

2024-07-18T08:06:01+02:00

While most maps are a representation of the surface of the earth at a reduced scale, some maps known as thematic maps are a representation of data distributed on the face of the earth. Within thematic maps, ethnic maps make up a special group since they have played a large role in defining state borders, especially during and after the First World War when territorial demands were made which were justified using ethnic maps. Many different mapping methods have been tried and while many can give a very accurate picture their interpretation is time-consuming hence they cannot be presented to decision-makers. This paper presents those mapping methods together with their scale which are ideal to be used for decisions on borders and analyzes their accuracy.

Application of column tests to derive transport parameters of manganese in mine waste dump material of Rudabánya

2024-06-12T11:32:45+02:00

The most accurate method to create a transport model of an area is to determine the transport parameters of a contaminant in the investigated porous media. The batch and column tests are the tools that can be used to derive this information. To describe the transport process in a column, 1D transport equation is applicable therefore the equation's analytical solution becomes possible. In our work, two-column test setups were investigated from the aspect of their accuracy in the determination of longitudinal dispersivity, retardation factor, and irreversible reaction rate constant, respectively. In the first measurement method, a solution with constant concentration (0.01 M Mn solution) was percolated through the column filled with mine waste dump material. In the second measurement method, distilled water was percolated through the column continuously but in a moment an impulse amount of manganese (10 ml 0.5 M Mn solution) was injected into the column at its bottom. The first measurement served the breakthrough curve (BTC), and the second measurement resulted the impulse curve (IMP). The retardation factor of Mn found in the media is similar in both measurement setups (R_BTC=1.87, R_IMP=1.47). The value of the irreversible reaction rate constant differs in the two experiments; an order of magnitude difference was found between the result of the breakthrough test (µ_BTC=6.94·10^-5 1/s) and the impulse test (µ_IMP=2.09·10^-4 1/s).

On the impact of hydrocarbon contamination on compaction and plasticity behavior of sandy clay soil. Case study: Northeast Hungary

2024-11-12T14:14:40+01:00

This study investigates the behavior of hydrocarbon-contaminated soils, using Atterberg tests and Modified Proctor Tests (MPT) conducted on sandy clay soil samples. By exposing the soil to higher artificial contamination percentages than has been reported in the literature, our approach gives a further comprehensive
analysis and provides a complex interpretation of the contamination process and its impact on compaction. The oil contamination led to an increase in the plastic limit and a decrease in the plasticity index. It also influenced the compaction behavior, resulting in a decrease in the maximum dry density. The analysis emphasizes the significance of considering higher contamination levels for a more robust understanding with implications for diverse engineering applications.