Kh. S. Shaaban

Some Physical Features of Glasses Synthesized from Some Environmental Wastes

New glasses based on wastes of limestone, phosphate, and cement kiln dust besides white sand were manufactured. The structure of the prepared glasses was studied by FTIR, thermal analysis, UV spectroscopy and ultrasonic techniques. The analysis revealed that increasing the content of SiO2 influences the concentrations of the structural units constituting the amorphous network. The values of the physical parameters; the density, ultrasonic velocity, the elastic moduli, the refractive index, the optical band gap and the glass transition temperature increase as the SiO2 content increases, which was attributed to the former role of SiO2 which strengthens the calcium borate network and the conversion of non-bridging oxygens into bridging oxygens. These factors increase the crosslink density and connectivity within the glass network and hence its rigidity.

Effect of MoO 3 Content on Structural, Thermal, Mechanical and Optical Properties of (B 2 O 3 -SiO 2 -Bi 2 O 3 -Na 2 O-Fe 2 O 3 ) Glass System

The glass system 40B2O3–20SiO2–9Na2O–1Fe2O3–(30-x)Bi2O3–xMoO3, x = (0, 5, 10, 12.5 and 15 mol%) was prepared and analyzed by using X-ray diffraction, IR spectroscopy, density, differential thermal analysis (DTA), optical properties and mechanical properties. The structural variations due to the increase of the MoO4 at the expense of the BiO3 structural unit increase the ultrasonic velocity and the elastic moduli along with a decrease of the density. The increase of the glass transition temperature, Tg, according to DTA confirmed this behavior. The values of the optical band gap Eg and refractive index have been determined and it was found that these parameters are sensitive to the increase of MoO3 content.

Fabrication and physical characteristics of new glasses from wastes of limestone and phosphorite rocks

In this work, new glasses were synthesized from wastes of limestone and phosphate rocks besides commercial borax. The glasses were characterized by FTIR, DTA, ultrasonic techniques and UV spectroscopy. It was found that the concentration of both CaO and P2O5 increases and the concentrations of B2O3 and Na2O decrease as the content of phosphate rocks increases. Variation of the contents of the different oxides affects the concentration of the structural units constituting the glass, which was indicated by the behaviour of the fraction N4 of BO4 units in the borate matrix. The density and the refractive index of the glasses decrease as the CaO and P2O5 contents increase, which was attributed to the increase of [BO3] structural units. On the other hand, the physical parameters such as the ultrasonic velocity, the elastic moduli, the optical bandgap and the optical polarizability increased, which was attributed to the higher coordination number of CaO6 compared with the coordination of borate structural units and to the former effect of P2O5. As a result, a polymerization of the total co-ordination number of the glass, crosslink density and connectivity within the glass network will occur.

Synthesis and Physical Characteristics of New Glasses from Some Environmental Wastes

New glasses from harmful environmental waste like cement dust; limestone phosphate and sand were fabricated. The constructions of these sample investigation by FTIR, mechanical and optical properties. The density and refractive index of these glasses increases by increasing of SiO2 concentration. Longitudinal (vL), and share (vT) velocities increase with addition of silicon oxide. The elastic moduli values were showing increasing as an increasing of SiO2 concentration. The increase in elastic moduli may be connected to changing of the coordination number with an addition of SiO2 and the increase the bond strength, average force constant and the crosslink density. DTA of the investigated samples with exclusive SiO2 contents shows the increasing in Tg values. The molar volume and the optical band gab of these glasses decreases with increase of SiO2 expense on CaO.

Structural Analyses of Halide Alkali Lead Borate Glasses

Glasses with the chemical formula 39PbO-1NaI- (60-X) Na2B4O7 – X CaO mol % (X = 0, 5, 10, 15, 20, 25 mol %). were prepared by the usual melt quenching technique. The density and the molar volume were determined. Ultrasonic velocities (longitudinal and shear) were measured in these glasses at room temperature. The elastic moduli, such as Young’s modulus (Y) or Bulk modulus (K) were determined and elastic properties were calculated in terms of the Makishima–Mackenzie model. The thermal stability criterion ?T was determined by using differential thermal analysis (DTA) with heating rate10 °C/min.

The Effect of TiO2 on the Optical and Mechanical Properties of Heavy Metal Oxide Borosilicate Glasses

The density, the molar volume, the rigidity, the UV reflectance and the glass transition temperatures of the x TiO2 – 20Na2B4O7 – 30PbO – 20SiO2 – (30-x) Bi2O3 glass system were determined. These physical parameters were acquired by using the DTA, ultrasonic and UV techniques to explore the effect of TiO2. The replacement of Bi2O3 by TiO2 decreased these physical parameters, which suggested the glass modifier role of TiO2. This attitude can be attributed to the smaller ionic radii, the density and the polarizability of TiO2 than that of Bi2O3. Moreover, according to the FTIR, TiO2 created non-bridging oxygens in the network that decreased the bond strength of the glass system. The decreases of the rigidity, the glass transition temperature and the optical band gap are sensitive to the decrease of the bond strength and the created non-bridging oxygens in the lead alkali borosilicate network. The obtained results were discussed in relation to the role of TiO2 in the lead borosilicate glass system.

Fabrication and Characterization of Glass and Glass-Ceramic from Cement Dust and Limestone Dust

Recycling the solid wastes like cement dust and limestone dust and using in the manufacturing of glass and glass - ceramics are strongly needed. These glasses fabricated by melt-quench technique. The X-ray diffraction (XRD) patterns of all the studied samples confirmed the amorphous nature These glasses have been investigated for their physical properties using density and molar volume, structural properties using FTIR spectroscopy, optical properties using UV-Vis spectroscopy, thermal analysis and mechanical properties. The density, molar volume and refractive index vary with the concentration of CaO. The variations of various physical, structural, thermal analyses, mechanical and optical properties with the concentration of CaO in this glass system depict a strong structural influence of CaO. The ultrasonic velocity of these glasses has been decreased with addition of CaO, this decrease is connected to the decreasing the bonding strength between Calcium - oxygen are lower than the bond between silicon - oxygen (32-106 k cals).The elastic moduli of these glasses determined experimentally and calculated theoretically, according to Makishima–Mackenzie model decreased with increasing of CaO. This behavior may be related to changing the coordination number with an increasing of CaO and the decrease in the average force constant and crosslink density. The crystalline phase of the prepared glass ceramic is diopside with the chemical formula (Ca MgO6 Si) in all selected samples.

Mechanical and Thermal Properties of Lead Borate Glasses Containing CaO and NaF

Glasses with the chemical composition 39PbO - 1NaF - (60-x){0.667B2O3-0.333Na2O }

Physical and Structural Properties of Lithium Borate Glasses Containing MoO3

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Optical and structural evaluation of bismuth alumina-borate glasses doped with different amounts of (Y2O3)

– x CaO (x =