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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 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]

• Different semiconducting quaternary compounds were examined by Phy-X / PSD software. • Gamma radiation attenuation parameters, as well as fast neutrons attenuation, were computed to select the best attenuator. • Cu 2 CoGeSe 4 sample has good fast neutron attenuating features. • Cu 2 CoGeTe 4 sample effectively absorbed gamma radiation by recording the maximum LAC. • Effective atomic numbers (Z eff) were computed for electron, proton, photon, alpha particle, and carbon ion interactions. The radiation-protection properties of the magnetic semiconducting quaternary compounds Cu 2 CoGeS 4 , Cu 2 CoGeSe 4 , and Cu 2 CoGeTe 4 were examined in this study by using Phy-X/PSD software with the selected gamma energy (0.015–15 MeV). The radiation shielding coefficients such as mass and linear attenuation coefficients (MAC) and (LAC), half-value layer (HVL), and mean free path (MFP) of the present semiconductors were calculated. Also, the total electronic and atomic cross-sections (ECS and ACS), the effective atomic number (Z eff), the effective electron density (N eff), and the effective conductivity (C eff) of these semiconductors were estimated to see how well they could protect against radiation. A comparative study occurred between the obtained results and the corresponding values of RS-253-G18, RS-360, RS-520 glasses, barite, chromite, and ferrite concrete. The results show that semiconducting samples with the best shielding performance outperform RS-253-G18, RS-360 glass, and RS-520 glass materials commonly used in nuclear applications. The Cu 2 CoGeTe 4 sample had the highest MAC , LAC, and ACS , as well as the highest ECS and Z eff values. The other two semiconductor samples had the lowest MAC , ECS, and Z eff values. For photons, charged particles (electrons, protons, alpha particles), and C-ion, Phy-X/PSD allows the calculation of the Z eff quickly and precisely across the entire energy range. This study indicates that the semiconductor samples can be utilized as radiation attenuators for various nuclear fields. [ABSTRACT FROM AUTHOR]

• Novel transparent glasses and glasses ceramic with composition 64TeO 2 - 10WO 3 - 10Nb 2 O 5 - 15KF- 1.0 La 2 O 3 - xTm 2 O 3. • The present glasses have high magnitudes of emission cross-section σ e FL (λ) are 1.37, 1.49, 1.54, and 1.64 × 10−20 cm2 at 1840 nm increasing with Tm3+ ions concentration in host tellurite glasses, which is important in laser applications.. • Ihe present glasses have a suitable value of the gain coefficient (λ) for lasing application and nonlinear optical devices. • Produced glasses compare well to the values that have been found for other tellurium hosts. Novel transparent glasses and glass-ceramics were fabricated by using melt-quenching technique with the following composition: TeO 2 –WO 3 –Nb 2 O 5 –KF–La 2 O 3 doped with Tm 2 O 3. Different properties and physical parameters of these glasses were investigated. As the concentration of Tm3+ ions increases, the linear refractive index increases while the optical energy gap decreases. With high Tm3+ ion concentration creates nucleation in the glass matrix this was investigated by x-ray diffraction. The Judd-Ofelt parameters used to calculate the electric and magnetic dipole transition probabilities, branching ratios, and radiative lifetimes of various excited states of Tm3+-doped parent glass. The emission cross section values for the 3F 4 →3H 6 transition computed by using the McCumber hypothesis. The stimulated emission cross section σ e F L (λ) and gain values of fabricated glass increase with Tm3+ ions. The spectroscopic quality and figure of merit (FOM) gain (σ e F L (λ) × τ R) factors were evaluated for the prepared transparent glass. Furthermore, the produced glasses were demonstrated to have low OH content and they have high fluoride ion content. These important properties of the glasses and glass-ceramics make them suitable for use in photonic applications. [ABSTRACT FROM AUTHOR]

• Synthesis of Sm 2 O 3 doped B 2 O 3 –SiO 2 -Li 2 O– Na 2 O–Al 2 O 3 glass to be used in photonic devices. • The area under the peak calculations of FTIR displays a higher presence of BOs. • The Judd-Ofelt analysis shows the ionic nature of Sm3+ ions with neighboring atoms. • Higher branching ratio values were obtained from the 6H 5/2 → 6F 1/2 emission transition. • Photoluminescence spectra under 402 nm excitation show white- reddish-orange emission at 402 nm. This research investigates the influence of the concentration of Sm+3 ions on the properties of a new borosilicate glass system with the composition 50B 2 O 3 – 14SiO 2 - 20Li 2 O– 15Na 2 O– 1.0Al 2 O 3 -x(Sm 2 O 3), where × = 100, 200, 300, 400, and 500 ppm. The glasses are characterized by XRD, FTIR, UV– Vis-NIR, and photoluminescence spectra. The XRD results proved that all glasses prepared are amorphous. Moreover, it was found that the values of density (ρ), and refractive index (n), rise with increasing of Sm+3 content. Otherwise, the value of molar volume, optical energy gap, and boron-boron distance decrease by increasing Sm+3 concentration. The structure of glasses studied was investigated by computing I n t e r n u c l e a r r i , Polaron radius r p , field strength F and the deconvolution of FTIR spectra. Judd-Ofelt theory was applied to clarify the structural changes and nature of the bonds of glasses prepared. Moreover, a spectroscopic quality factor, the branching ratio (βr), and lifetime (τ) are calculated with the use of Judd-Ofelt parameters. The color chromaticity of the glasses confirmed that the emission in the white-reddish orange region under 402 nm excitation is affected by the concentration of Sm3+ ions. The results of photoluminescence emission stimulated emission cross-section, and CIE chromaticity leads to the conclusion that the glass BSLNA5 are promising candidates as laser material for light-emitting diode (LED). [ABSTRACT FROM AUTHOR]

• High optical quality borosilicate glasses doped with Dy 2 O 3 were fabricated. • Aluminum borosilicate glasses doping with Dy3+ can used as luminescent device applications for white light generation. • The present glasses have high magnitudes of emission cross-section and branching ratio, which is important in laser applications. • Higher asymmetrical degree of present matrix around Dy3+ ions, and strong covalent bonding nature with surrounding atoms. • The luminescence performance of fabricated glasses showed a strong transition. We manufactured a new series of borosilicate glass doped with Dy3+ ions using a glass-quenching technique. To achieve the unique luminescence properties of our prepared glass, rare earth (Dy 2 O 3) was incorporated into the glass matrix. The photoluminescence spectrum revealed five intense emission bands allocated at wavelengths 483 nm, 575 nm, 665 nm, 712 nm, and 752 nm, attributed to the transition from 4F 9/2 → 6H 15/2 , 4F 9/2 → 6H 13/2 , 4F 9/2 → 6H 11/2 , 4F 9/2 → 6F 3/2 , and 4F 9/2 → 6H 9/2 respectively. From the emission results of prepared glass at excitation wavelength 350 nm, we used our glass as a new solid laser source for the production of white light. From radiative properties measurements, the luminescence performance of fabricated samples showed a strong transition, with limited transition life and high values of branching ratio. Additional physical parameters were evaluated, such as density, optical packing density, and molar volume. By X-ray diffraction, we observed that all the prepared samples were of the amorphous phase. Fourier Transform Infrared Spectroscopy demonstrated the effect of incorporating Dy 2 O 3 on the structure of our prepared glass. From the spectrum of absorption transitions, optical band gap E g , refractive index (n), and Urbach energy (ΔE) were obtained. To research glass bonding nature, Judd-Ofelt strength parameters (Ω λ and λ = 2, 4, 6) were obtained; these parameters were used to achieve the spectroscopic efficiency factor, branching ratios (βr), and lifetime (τ). Moreover, the cross-sections of emission and absorption of our prepared glass was estimated. Finally, our cumulative study findings indicate that these manufactured samples may be used in luminescent display devices as a white light laser diode (W-LED). [ABSTRACT FROM AUTHOR]

• (XRD) the analysis was confirmed the amorphous nature. • (FTIR) and Raman of TLZNT glasses shown the formation of (NBO). • E opt was decreased and ΔE was increased with increasing Tm 2 O 3 mol%. • J-O parameters indicated the covalency of the Tm-O bond and tend to be more ionic. • DSC illustrated decreasing of Tg and increasing of Δ T with increasing Tm 2 O 3 mol%. • The results herein denote that the TLZNT glasses are a promising solid material for optical applications that use light-emitting diodes LED. Tellurite glass (TLZNT) with compositions 75TeO 2 –5Li 2 O–10ZnO–(10–x) Nb 2 O 5 −x Tm 2 O 3 , (doped with x = 0, 0.5, 1.0, 1.5, 2, and 2.5 in mol%) were prepared through the melt quenching technique. In the present work, the glass transition value slightly decreased from 351 to 347 °C otherwise thermal stability Δ T c h a n g e s f r o m 118 t o 164 °C of (TLZNT) glasses, investigated by using differential scanning calorimetry (DSC). The influence of Tm3+ ions (RE) on the structure of the TLZNT glasses was studied through different techniques such as X-ray pattern diffraction and Raman/Fourier transform infrared spectra. Moreover, the ratio of the relative bridging oxygen (BO) to non-bridging oxygen (NBO) in the prepared glass network was determined. Next, the packing density of oxygen, density, molar refraction, molar volumes, metallization criterion, molar polarizability, and linear refractive index of the prepared glasses were computed. The optical energy gap, the Judd–Ofelt parameters (J–O), the radiative branching ratio (β R), and the radiative lifetime (τ R) of Tm3+ in TLZNT glasses were determined. The absorption cross section (σ A B S ), emission cross section (σ E M I S ) , and gain coefficient (σ G A ) were evaluated in the range wavelength of 1500–2000 nm. The high value of σ EMIS (1.50 × 10−20 cm2) of the 3H 6 → 3F 4 transition of TLZNT3 glass was reported. We produced TLZNT glasses in which the addition of Tm 2 O 3 improved the ΔT against nucleation and crystallization what is in good agreement with the decrease of the average force constant (F -) from 225 to 221.7 N/m with increasing Tm 2 O 3. For the 1870 nm emission band, the emission cross section was determined to be approximately 1.5 × 10−20 cm2. Finally, the results herein will denote that the TLZNT glasses are a promising solid material for optical applications that could be excited by a commercial laser diode (LD). [ABSTRACT FROM AUTHOR]