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Herein, we investigate silicate-phosphate glasses from the SiO 2 –P 2 O 5 –K 2 O–MgO–SO 3 system enriched with various amounts of sulfur, as a nutrient indispensable for the proper development of plants, in order to gain a profound understanding of the structure of such materials. An inherent capability of glasses from the studied system to incorporate sulfate groups into the vitreous matrix was discussed on the basics of the results from XRF, XRD and internal Al 2 O 3 standard techniques. It has been found, that as much as 3 mol.% of SO 3 can be loaded into the glass batches to obtain fully amorphous material, while beyond this limit K 2 SO 4 crystallizes within the matrix. Comprehensive spectroscopic investigation, comprising Raman, Middle Infrared (MIR), 29Si and 31P MAS-NMR, X-ray absorption spectroscopy (XANES and XAS) techniques, has been implemented in order to determine an impact of sulfur on silicate-phosphate glass framework. On this basics, it has been concluded, that sulfur exists in the vitreous matrix in the form of specific domains, in which [SO 4 ]2- anions are surrounded by the shell of charge-compensating K+ cations. Such sulfate groupings maintain their individuality without direct bonding to silico-oxygen or phospho-oxygen subnetwork. Spectroscopic results revealed also, that the presence of sulfur affects silico-oxygen subnetwork to a significantly greater extent than the phospho-oxygen one. It has been demonstrated, that along with SO 3 addition, the more polymerized Q S i 3 units increase in abundance at the expense of less polymerized Q S i 2 groups. Results of the present study are believed to contribute to a greater understanding of the nature of sulfur-bearing oxide glasses. [ABSTRACT FROM AUTHOR]

The paper presents a tally of the results of thermal analysis TG/DTG/DSC of selected fuels (hard coal, agro biomass and forest biomass), waste (coal sludge, fly ash), quartz sand with the organic material, and recyclate of polyamide PA6. The materials differ in composition and calorific values. The aim of the study was a complex comparative analysis of the tested materials inthe scope of potential use of coal fuels, biomass and coal waste to create polymer composites, as well as thermal co-utilization of polymer waste, and energy recovery from plastic waste. The thermal analysis permits to illustrate the change of a sample mass and to obtain information at what temperature ranges these changes occur. It also enables to notice whether any changes related to heat absorption or release take place in the tested substance, as well as identify exothermic and endothermic effects during thermal process. The authors stated that the changes of values on the DSC, TG and DTG curves of the tested materials during the thermal process result mainly from their primary composition. The analyzed quartz sand with organic substance, and fly ash, show the lowest exothermic effects in the air atmosphere, in contrast to other tested materials, due to low carbon content and volatiles matter. Among the considered fuels: hard coal, coal sludge, biomass, coal has the highest carbon content and calorific value, which is reflected in the maximum DSC values. • The polyamide is distinguished from the tested materials by high calorific value. • The endothermic peak at 219.9 °C is responsible for melting of polyamide. • The tested materials show specificity of behavior in high temperature conditions. • It is important to recognize of possibility creating different polymer composites. • The properties of polymer waste make it possible to energy recovery. [ABSTRACT FROM AUTHOR]

Glasses have been synthesized in the system P 2 O 5 SiO 2 K 2 O MgO CaO modified by addition of MoO 3 . Glasses were prepared by conventional fusion method from 40 g batches. The influence of Mo-cations on the analysed glass structure was investigated by means of Raman and 31 P MAS-NMR techniques. It has been found that molybdate units can form Mo[MoO 4 /MoO 6 ] O P and/or Mo[MoO 4 /MoO 6 ] O Si bonds with non-bridging oxygens atoms of Q 2 methaphosphate units, resulting in the transformation of chain methaphosphate structure into pyrophosphate and finally into orthophosphate structure. It has been also found that increasing amount of MoO 3 in the structure of investigated glasses causes their gradual depolymerization and molybdenum ions in the analysed glass matrix act as modifying cations. [ABSTRACT FROM AUTHOR]

Highlights: [•] Glasses from the SiO2 P2O5 K2O CaO MgO MoO3 system were prepared and analysed. [•] Glasses were characterised by spectroscopic methods. [•] The introduction of MoO3 into the glass structure results in framework depolymerisation. [Copyright &y& Elsevier]

Highlights: [•] Glasses from the SiO2 P2O5 K2O CaO MgO MnO2 system were prepared and analyzed. [•] Glasses were characterized by spectroscopic methods. [•] The relation between the structure and chemical activity of glasses was found. [Copyright &y& Elsevier]

Abstract The synthesis of tialite was carried out by means of the solid state reaction technique using heterogeneous nucleation. The influence of the temperature of synthesis and simultaneous sintering (1250–1350 °C) on the yield of reaction and densification of the systems was investigated. Reference samples, consisting of stoichiometric mixture of titanium and aluminium oxides as well as the samples containing such additives as MgO, SiO 2 and MgTi 2 O 5 were prepared. Applying the DSC analysis the synthesis temperatures of systems differing in the substrate composition were determined. The phase composition of synthesis products was determined by means of XRD analysis combined with Rietveld's method. The density of the obtained materials was determined by the Archimedes method. SEM observations enabled microstructures and homogeneity of sinters to be compared. On the basis of the conducted research it was found that using oxide additives containing magnesium cations allows the synthesis efficiency exceeding 95% as early as at the temperature of characterized by a homogeneous microstructure with a lower number and a smaller size of microcracks. [ABSTRACT FROM AUTHOR]

This paper presents results of in-plane shear tests carried out at the ZAG laboratory in Ljubljana (Slovenia) on a RC frame with masonry infill made of clay blocks (KEBE OrthoBlock). The frame was loaded with constant vertical loads at the top of the columns and then by gradually increasing horizontal cyclic loads at the top beam level. Acquired forces and measured displacements allowed capturing hysteretic behavior for determination of dissipation energy. In addition, two Digital Image Correlation (DIC) systems, Aramis and the CivEng Vision, were used to visualize the behavior of the tested specimens, with an emphasis on computing locally required information about the behavior of highly deformable interfaces. Three types of specimens were tested in-plane: the reference specimen in form of plain RC frame, the reference specimen with constructed masonry infill without any strengthening and the specimen, previously damaged and then strengthened on both sides using glass mesh bonded to the infill and the RC frame using flexible adhesive made of polyurethane matrix (Glass Fiber Reinforced PolyUrethane - GFRPU system). The strengthening process, allowed the specimen to withstand additional cyclic loads, reaching a maximum drift of 3.6 % without serious damage disqualifying the structure from further exploitation. The GFRPU strengthening system was found to be highly effective in preventing infill collapse of damaged masonry infill wall during in-plane loading. Additionally, the results of extended thermal analysis of PU are presented as polymers are, in general, a material, poorly resistant to heat. However, the analyzed PU manifested stable properties up to 200 degrees Celsius, which makes this material promising in civil engineering applications at elevated temperatures. • In-plane push-over cyclic tests of RC frame strengthened by flexible GFRPU system. • Maximum frame drift of the value 3.6 %, without serious damage. • GFRPU strengthening system was very effective and resistant to out-of-plane forces. • FRPU matrices made of PU are resistant to elevated temperatures. • Local large deformations of GFRPU system identified by DIC measurements. [ABSTRACT FROM AUTHOR]

Abstract: Silico-phosphate glasses of XCaPO4–SiO2 (X=Na+ and/or K+) system have been the subject of the presented investigations. One of the most important problems is to ensure proper biomaterial mechanical resistance. This can be achieved by introduction of proper additions, usually Al3+, into glass structure or/and partial glass devitrification. To design direct crystallization process properly it is necessary to know the texture and structure of the glassy precursor. Microscopic investigations have made it possible to find out that in all the glasses studied liquation takes place. A small addition of Al3+ influences homogeneity of the glass texture. It has been established (EDX investigations) that addition of aluminium dramatically changes the composition of the matrix and inclusions. Spectroscopic investigations (FTIR, NMR) have shown that both, the matrix and the inclusions exhibit domain composition whose structure is close to that of the corresponding crystalline phases. Domains can be considered as the specific ‘‘crystallization nuclei’’ which have a decisive impact on the process of directed glass crystallization. Based on DTA examinations it has been found out that crystallization of the glasses from XCaPO4–SiO2 system is a multistep process while the crystallization of glasses from XCaPO4–SiO2–AlPO4 system is a one step process. [Copyright &y& Elsevier]

The development of civilization is associated with generating an increasing amount of various types of waste. More and more restrictive legal regulations require limiting their storage, which thermal methods should replace. Thermal recycling of plastic waste also enables the use of their energy potential. In this article, the authors presented basic research results comparing the combustion process course of selected plastic waste with coal waste, agro and forest biomass. For this purpose, thermal analysis methods were used to determine temperatures at which the maximum heat generation and emission of selected gases occurs during waste combustion. The proximate and ultimate analysis, X-ray fluorescence (XRF) analysis, and mercury content analysis made it possible to determine the composition of considered waste. The model using fuzzy logic methods was developed to predict the maximum values of generation heat from the tested materials at temperatures. The authors assumed the following research hypotheses: 1) the calorific value and composition of the materials are reflected in the maximum values of heat generated and pollutant emissions, and 2) the developed fuzzy logic-based model allows the prediction of maximum values generated heat from the tested waste, during the analyzed thermal processes. The results of thermal analysis for the considered waste with the given composition, as well as the results of predicting the behaviour of these materials in thermal conditions, constitute the innovation of this article. • Thermal curves reflect the initial materials' composition. • EGA curves identify released gases. • The model predict the thermal process course. [ABSTRACT FROM AUTHOR]