Study on the Characteristics of Materials and Manufacturing Techniques for the Mural Paintings in Daeunjeon at Ssanggyesa Temple, Jindo

This study identifies the structure and material characteristics of the mural paintings in Daeungjeon at Ssanggyesa temple in Jindo by conducting scientific research and analysis including microscope examination, SEM-EDS, XRD, particle size analysis, and others. According to the analyses, the murals were considered to be of a typical soil mural style for Korean Buddhist murals, given that the walls were made of sand and soil and the murals had layers consisting of wall layers and a finishing layer. However, some finishing layer used calcite, while some ground layer used zinc white beneath the thick paint. In addition, there were similar features to those found on the surfaces of oil paintings such as cracks along with the paint layer, high gloss on surfaces, and thick brush strokes in many areas. It was found that the walls on which the murals were painted were made of soil but that the paint layer was created based on the oil painting technique using drying oil. It determined that the murals were painted in a unique painting style that is rarely found in other typical Buddhist murals in Korea.

Selenium Nanoparticles as an Innovative Selenium Fertilizer Exert Less Disturbance to Soil Microorganisms

Selenium (Se) is an essential trace element in the human body. Se-enriched agricultural products, obtained by applying Se fertilizer, are important sources of Se supplement. However, Se fertilizer may cause a series of environmental problems. This study investigated the transformation of exogenous selenium nanoparticles (SeNPs) and selenite (SeO32–) in soil and explored their effects on soil microbial community and typical microorganisms. SeNPs exhibited a slow-release effect in soil, which promoted the growth of soil microorganisms and enriched soil probiotics. SeO32– was converted to a stable and low toxic state in soil, increasing persistent free radicals and decreasing microbial abundance and diversity. The influences of SeNPs and SeO32– on two typical soil microorganisms (Bacillus sp. and Escherichia coli) were also evaluated, and SeNPs were more difficult to enter into microorganisms directly, with lower toxicity and higher safety. These results indicated that SeNPs were a more environment-friendly Se additive for agriculture applications. This work provides useful information for better understanding the environmental fate and behavior of Se fertilizer in the soil.

Research on the Influence of Typical Soil Parameters on Critical Breakdown Field Strength and Residual Resistivity Based on Discharge Topography

Partial discharge of soil occurs when a lightning current enters the ground, and the strength of partial discharge is closely related to the magnitude of its critical breakdown field strength. Therefore, how to accurately obtain the variation law of the typical soil critical breakdown field strength and residual resistivity is the key to realizing the safe operation of the grounding devices and cables in the ground. This paper first selects a variety of typical soils to study the influence of various factors on the morphology of the discharge channel, and then studies the calculation methods of the soil critical breakdown field strength and residual resistivity under the introduction of different discharge channel morphologies and structures, and further discusses the reason why typical soil media factors have a small impact on the critical breakdown field. The experimental results show that under the same conditions, the critical breakdown field strengths of different soils from small to large are sand soil, loam soil and Yellow cinnamon soil. The largest ratio of residual resistivity to initial resistivity of the three soils is sand soil.

Analytical stress-strain relation for soils

A new stress-strain relation capable of reproducing the entire stress-strain range of typical soil tests is presented. The new relation involves a total of five parameters, four of which can be inferred directly from typical test data. The fifth parameter is a fitting parameter with a relatively narrow range. The capabilities of the new relation is demonstrated by the application to various clay and sand data sets.

Biostability of synthetic polymer materials – polyethylene, polypropylene and polycarbonate – in the conditions of Surgut

The paper is devoted to the study of biostability of polyethylene, polypropylene and polycarbonate in the conditions of Surgut after their presence within a year in different types of soils swamp-podzolic soil, culturosem and urbanozem. The studied types of soils differ in their chemical composition urbanozems are saturated with bases, have a slightly alkaline reaction, they also contain an excess of lead content due to their close location to highways. In the studied soils bacterial microflora prevails over mycoflora, the amount of heterotrophic and lithoautotrophic microflora in urbanozems is especially high, which is due to the high anthropogenic load on these soils. For seeds and seedlings of wheat and radish the stimulating effect of these soils was revealed. Micromycetes isolated from the surface of polypropylene and polyethylene pipes are typical soil saprotrophs that can act as biodestructors of polymers. In the field experiment all the materials under study are biostable, and there was a slight change in the color of the cross-linked polyethylene sample. In the laboratory experiment certain instability of all the materials under study was revealed; their gradation in terms of mushroom resistance (from resistant to unstable) is as follows: low-density polyethylene, polypropylene random-heat-resistant copolymer, polycarbonate, cross-linked polyethylene. The nature of damage to low-density polyethylene (polyethylene film) is superficial, which corresponds to the literature data.

Modeling the Effectiveness of Cooling Trenches for Stormwater Temperature Mitigation

Due to elevated runoff stormwater temperatures from impervious areas, one management strategy to reduce stormwater temperature is the use of underground flow through rock media termed a cooling trench. This paper examines the governing equations for the liquid phase and media phases for modeling the temperature leaving a cooling trench assuming that changes in temperature occurred longitudinally through the cooling trench. This model is dependent on parameters such as the media type, porosity, media initial temperature, inflow rate, and inflow temperature. Several approaches were explored mathematically for evaluating the change in temperature of the water and the cooling trench media. Typical soil–water heat transfer coefficients were summarized. Examples of predictions of outflow temperatures were shown for different modeling assumptions, such as well-mixed conditions, batch mixing and subsequent release, and steady-state and dynamic conditions. Several of these examples evaluated how long rock media would cool following a stormwater event and how the cooling trench would respond to multiple stormwater events.