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This experimental study aimed to design an autoclaved aerated concrete (AAC) with different kind of glass wastes as an alternative fine aggregates for mass housing projects that will meet the requirements in order to help contribute to the industry in saving the environment. Moreover we want to encourage the government to find solutions regarding the disposal to landfills of glassy waste materials and provide new knowledge to the contractors and developers on how to improve the construction industry methods and services by using glassy waste to sustain good product performance and meet recycling goals. Different kinds of glass wastes in the form of sub grain packaging glass cullet, CRT (Cathode Ray Tube) panel glass waste and calsi glass, were used as a sand replacement in AAC production. Large proportion of the post-consumer glass is recycled into the packaging stream again, but some sub grain packaging glass cullet does not meet the strict criteria for packaging glass thus is sent to landfill. CRT is classified as a hazardous glass waste and there are several issues surround CRTs which create barriers to increased recovery of the glass. In countries e.g. Latin America and Asia where still CRT glass is being produced even when shredder, the glass stream is a mixture of panel and funnel glass, making it difficult for reuse in new CRTs. Based on our knowledge also calsi glass as a processed blast furnace slag is not used in packaging production. The viability of current and novel applications of mentioned glasses is examined here. Although aerated concrete was initially envisaged as a good insulation material, there has been renewed interest in its structural characteristics in view of its lighter weight, savings in material and potential for large scale utilization of wastes. Due to this fact we undertake the studies of an influence of different amounts of glass wastes onto properties of aerated concrete in terms of physical (microstructure, density), mechanical (compressive and tensile strengths) and chemical characteristic. Use of milled waste glass in concrete as partial re-placement of sand represents an important step towards development of sustainable (environmentally friendly, energy-efficient and economic concrete-based infrastructure systems. [ABSTRACT FROM AUTHOR]

The problem with the waste from electric and electronic equipment (WEEE), consisting of about 80% of television sets and computers containing a cathode ray tube (CRT) have just begun to deal with. Cathode ray tubes (CRTs) are the video display components of televisions and computer monitors (EPA, 1995). Arising problem related with recovery and recycling of CRT glass stimulates examinations aimed at making cullet-based ceramic materials of reinforced mechanical strength. Glasses as cone and neck contain principally different lead contents another dangerous elements instead panel glass has other heavy metals (Ba, Sr, etc.) that forbid their recycling in the glass industry for the production of containers, domestic glassware and glass fiber. As it is well known concrete is an excellent material for immobilization of these metals, what was the reason to undertake this research. The use of CRT (Cathode Ray tube) waste glasses in concrete has attracted a lot of interest worldwide due to the increased disposal costs and environmental concerns. Because of silica large quantities CRT glass in the theory is a pozzolanic in nature, thus it can be used as a sand replacement in light concrete. The research was performed with use of concrete mortars. As a reference concrete mortar a mix of cement, sand, expanded clay aggregate and water was used. The purpose of this work was to investigate the influence of additives e.g. CRT glass cullet as an aggregate, and fluidized fly ash on concrete properties. Based on obtained results both CRT glass cullet and fluidize fly ash improved compressive and flexural strength in respect of standard concrete mortar without these additives. The use of CRT glass as a sand replacement caused the increased of compressive strength of concrete mortar of about 16% and its flexural strength of about 14%. [ABSTRACT FROM AUTHOR]

The present study's basic objective is to evaluate the photon shielding features of the quaternary compound Cu 2 CdSn 3 S 8 and three different binary compounds CuS, CdS, and SnS by carrying out Phy-X/PSD software between 0.015 and 15 MeV photon energies. The samples' radiation shielding capabilities were compared with those of different concretes and commercial glasses reported in the literature. Photon interaction parameters like MAC, LAC, HVL, TVL, MEF, ACS, ECS, Z eff , N eff , C eff , Z eq , EBF , and EABF are represented in the selected energy range. The MAC and LAC values of the tested samples are greater than certain concrete types commonly used for radiation safety. The measured values represent that SnS binary compound sample has higher values for MAC, LAC, Z eff , C eff , ACS, ECS, EBF, and EABF and lower HVL and MFP values. The Cu 2 CdSn 3 S 8 , CuS, and SnS FNRCS values are higher than the corresponding values of RS-253-G18, RS-360, and RS-520, so the studied samples have superior neutron attenuation properties. CuS possesses the best FNRCS (= 0.102) among the present studied compounds. • Three different binary sulfide compounds and the quaternary compound were examined by Phy-X/PSD software • Gamma radiation attenuation parameters, as well as fast neutrons attenuation, were computed to select the best attenuator • CuS has poor γ-ray shielding features, but it indicates good neutron shielding properties • The denser sample SnS effectively absorbed gamma radiation by recording the maximum LAC • SnS achieved the highest ACS and ECS values but the lowest EBF and EABF values [ABSTRACT FROM AUTHOR]

Abstract: The purpose of this work was to investigate the spectroscopic properties of Pr3+ ions of various concentrations embedded in a new matrix, namely a tellurite–tungstate glass with the molar composition 60%TeO2–27%WO3–10%PbO–3%La2O3 (TWPLa). The optical absorption edge of the TWPLa matrix has been described within the Urbach approach, while the absorption and fluorescence spectra of the Pr3+-doped TWPLa glasses have been analyzed in terms of the standard Judd–Ofelt (J–O) theory along with the luminescence decay of the 3P0 and 1D2 levels of the Pr3+ ion. A significant influence of the Pr3+ ion concentration on the photoluminescence intensity as well as on decrease of the lifetimes of both levels has been explained by a non-radiative energy transfer between the ions through different cross-relaxation channels. The spectroscopic studies have been completed with ellipsometric measurements providing the dispersion relation of the refractive index of the investigated glasses that has been taken into account in the J–O analysis. [Copyright &y& Elsevier]

Abstract: Multicomponent telluride-tungstate glasses containing Nd3+ and Er3+ ions were studied experimentally at 77 and 293K using spectroscopic methods. The Judd–Ofelt intensity parameters were derived from the absorption spectra and used to calculate the radiative lifetimes and branching ratios. The quantum efficiency η =0.95 of the 4F3/2 level of Nd3+ ion is higher than the typical value of other tellurite-based glasses. For low concentration of Er3+ ions, the luminescence decay of the 4S3/2 and 4I11/2 levels is governed by radiative transitions and multiphonon relaxation involving the Te-O highest energy vibrations. [Copyright &y& Elsevier]