Digitization of the multi-compositional Storkwitz carbonatite diatreme (Delitzsch Complex, Germany)

<p> </p><p>The Storkwitz diatreme is a multiphase composite body within the Late Cretaceous Delitzsch Complex in north-western Saxony, Germany. The lithology of the Delitzsch Complex varies from rauhaugite and fenite aureole to ultramafic and alkaline lamprophyric intrusions (dykes, sills and pipe-shaped bodies) accompanied by the formation of diatremes of variable composition (Krüger et al., 2013; Röllig et al., 1990). The final stages are represented by beforsite and alvikite dykes (Röllig et al., 1990). The multi-component nature of the Storkwitz diatreme can be attributed to the formation of polymict breccias and numerous injections of compositionally varied carbonatites (Gevorgyan et al., 2020; Seifert et al., 2000).  </p><p>The entire area was extensively explored through an intensive drilling campaign by the <em>SDAG Wismut</em> between 1972 and 1989, due to a locally increased REE content. For a better understanding of the development of the diatreme, detailed petrographical observations and new imaging methods on extensive drill core material were applied. The combination of microscopic images and high-resolution 2D-images allows to create 3D-models of drill core sections via photogrammetry. Identifying the components (xenoliths and intraclasts) and analyzing the pattern of their distribution in the 3D-models of drill cores will enable obtaining textural information of the minerals within the rocks.</p><p>Further investigations using Hyperspectral Imaging (HIS) for chemical information, to be carried out in cooperation with the <em>Institute for Mine Surveying and Geodesy, TU Bergakademie Freiberg</em>, combined with mineralogical information and 3D-models, will provide new insights into the shape and geometry of the diatreme body.</p><p> </p><p><strong>References</strong></p><p>Gevorgyan, H., Schmidt, S., Kogan, I., Lapp, M., 2020. EGU2020-10678.</p><p>Krüger, J.C., Romer, R.L., Kämpf, H., 2013. Chemical Geology, 353, 140-150.</p><p>Röllig, G., Viehweg, M., Reuter, N., 1990. Zeitschrift für Angewandte Geologie, 36, 49-54.</p><p>Seifert, W., Kämpf, H., Wasternack, J., 2000. Lithos, 53, 81-100.</p>

Experimental and Theoretical Prediction Model Research on Concrete Elastic Modulus Influenced by Aggregate Gradation and Porosity

In this research, we developed a four-phase model, which takes the aggregate gradation and porosity into account in the prediction of the elastic modulus of concrete, based on the micromechanical theories. The model has been verified with experimental results. First, using the Mori Tanaka and the differential self-consistent (DSC) methods, the pores in both the mortar and interfacial transition zone (ITZ) were homogenized. Then, the continuously graded aggregates were divided into finite aggregate size intervals. Further, using the generalized self-consistent model and multiphase composite model derived from the Mori Tanaka method, an aggregate gradation model for the prediction of the elastic modulus of concrete was developed. By simulating the pores in concrete with expanded polystyrene sphere (EPS) grains, the effect of overall porosity on the elastic modulus of concrete was investigated. The research results show that aggregate gradation and porosity have remarkable influence on the elastic modulus of concrete, and the proposed model is effective to estimate the elastic modulus of concrete, the deviation between the predicted elastic modulus and experimental elastic modulus is less than 8%. The elastic modulus decreases with increasing ITZ porosity. However, for ITZ porosity exceeding 40%, the decrease in the elastic modulus is large with increasing ITZ porosity. For a fixed overall porosity, the ITZ porosity owned more influences than the mortar porosity on the elastic modulus of concrete. Enhancing the ITZ elastic modulus and decreasing the ITZ thickness are efficient in increasing the elastic modulus of concrete.

The Impact of In Situ Polymerization Conditions on the Structures and Properties of PANI/ZnO-Based Multiphase Composite Photocatalysts

We have synthesized polyaniline/ZnO-based (PANI/ZnO) multiphase composite photocatalysts from acid media by a newly proposed two-step in situ polymerization. The first step of synthesis yielded PANI salt required for the PANI/ZnO synergistic effect. In the second step, the aniline oxidation continued, without ZnO dissolution, and it produced PANI base. Thus, both PANI salt and base phases in the composites were detected by FTIR and UV/Vis, while the presence of both ZnO and PANI polymer was confirmed by XRD. Additionally, XRD also showed Zn5(OH)8(NO3)2·2H2O and Zn(SO4)(H2O) phases in PANI/ZnO-based multiphase composites. Furthermore, the impact of the synthesis conditions on the morphology of the composites was investigated by FE-SEM. The images displayed that ZnO particles were encapsulated in PANI sheets that were formed by the aniline oligomers. Photocatalytic evaluation of PANI/ZnO-based catalysts (i.e., degradation of Acid Blue 25 dye) was conducted and the obtained results confirmed that all the studied composites experienced the PANI/ZnO synergistic effect. It was observed that the best photocatalytic properties were held by the PANI/ZnO_2 sample due to its optimal particle size.

Accelerated Weathering of Polylactide-Based Composites Filled with Linseed Cake: The Influence of Time and Oil Content within the Filler

This paper presents the effects of accelerated weathering on the properties of polylactide (PLA) composites filled with linseed cake. The particle-shaped waste filler with different linseed oil content (0.9–39.8 wt %) was incorporated with constant amount of 10 wt % to a polymeric matrix and subjected to accelerated weathering tests with different exposition times. The structure of the composites, their mechanical, thermal, and thermo-mechanical properties were evaluated by means of scanning electron microscopy, tensile test, dynamic mechanical thermal analysis, and differential scanning calorimetry prior to and after weathering. The results of the measurements were analyzed in reference to the amount of crude oil contained in the filler. The behavior of the multiphase composite during weathering was described. It was found that the oil-rich samples during the first stage of the process showed increased resistance to hydrolytic degradation due to their relatively high crystallinity. The presence of water and elevated temperatures caused swelling of the filler and cracking of the polymeric matrix. Those discontinuities enabled the plasticizing oil to be rinsed out of the composite and thus water penetrated into the samples. As a result, the PLA-based composites containing oil-rich linseed cake were found to be more vulnerable to hydrolytic degradation in a longer time.