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Zirconia-toughened alumina (ZTA)/Al2TiO5 composites were prepared via a sol–gel route. The prepared samples were uniaxially pressed and pressurelessly sintered at 1650–1700 °C for 1 h. The microstructure, densification, and X-ray diffraction patterns of the sintered ZTA/Al2TiO5 composites were investigated, and their mechanical properties, thermal coefficient, and shock resistance were characterized. The addition of Al2TiO5 hindered the grain growth of the alumina particles and enhanced the relative density, Vickers hardness, and bending strength of the composites compared with pure ZTA samples. The fracture toughness was improved by 19% upon the addition of 40 wt% Al2TiO5. Moreover, increasing the Al2TiO5 content resulted in an improvement in the thermal shock resistance. [ABSTRACT FROM AUTHOR]

In this work, superparamagnetic Fe3O4/C core/shell nanoparticles (NPs) were synthesized using a room‐temperature and green route combining co‐precipitation method, followed by hydrothermal process. The prepared nanoparticle was utilized as an adsorbent for the removal of Pb+2 ions from a wastewater. The effect of various parameters; such as pH, dose of adsorbent, contact time and concentration of lead ions on the adsorption capacity were examined in details. The adsorption capacity (qm) of Fe3O4/C NPs was estimated from the Langmuir isotherm curve and was found to be 244 mgg−1. Interestingly, the produced Fe3O4/C NPs exhibited a rapid removal of toxic lead metal ions from wastewater effluents and the adsorption kinetics is well described by pseudo‐second‐order model. Furthermore, the data of Pb2+ adsorption is best fit for the Langmuir model. Moreover, the Fe3O4/C core/shell NPs were recycled and reused for at least five times without a significant loss of adsorption efficiency. A cconvenient and cost‐effective hydrothermal approach is developed for the synthesis of highly efficient superparamagnetic Fe3O4/C core/shell NPs as adsorbent materials for the removal of toxic lead metal ions from wastewater [ABSTRACT FROM AUTHOR]

In the present study inorganic/organic hybrids reinforced by introducing titanium (TiO2) in the form of Ti-n-butoxide were prepared. The phase composition, microstructure and mechanical properties of the prepared hybrids were investigated. Increasing the titanium content gradually enhanced the mechanical data of the prepared hybrids. The formation of apatite on the surface of the prepared hybrids was examined in SBF (simulated body fluid). In vivo studies revealed the ability of the hybrids to regenerate bone tissue in femur defects of adult male rabbits five months after surgery. The prepared hybrids are considered to be promising materials for bone substitutes or bone filler. [ABSTRACT FROM AUTHOR]

There are a great number of rocks in nature that may be used to substitute for feldspars as fluxing alkali - containing raw materials. These having a greater fluxing power than the conventional fluxes and are desirable for ceramics for intensification of the firing processes. Among the great variety of nonconventional raw materials, granite has been chosen for the present study. In the present study granite and clay, from Sinai, Egypt were characterized and employed to obtain porcelainized stoneware tiles. The chemical and mineralogical compositions were analyzed by X-ray fluorescence spectrometry and X-ray diffraction analyses, respectively together with an optical microscope. Densification was studied according to ISO rules, while sinterability was estimated by optical dilatometry. Mechanical properties, phase composition and microstructure of the fired bodies were accomplished in order to determine the relationship between them. The results show that the bodies produced fulfil the requirement of the ISO 13006 standard, group BIa (porcelain tiles). [ABSTRACT FROM AUTHOR]

The filter cake produced from the processing of juice purification during the production of sugar from sugar-beet is a solid waste, which represents a major problem unless it is utilized. Accordingly, the aim of the present work is to study the suitability of sugar-beet filter cake as a novel starting material in the preparation of anorthite bodies. To synthesize anorthite bodies, El-Tieh kaolin (Al2O3.SiO2.2H2O) from Sinai, Egypt, was used as a source of alumina and SiO2, while the filter cake was used as a source of CaO. A predominant anorthite phase was found to be present on sintering the anorthite batches at 1200 °C and up to 1350 °C for 1 h. The prepared bodies possess a bending strength of 25.23 MPa and a relative density of 64.5%. [ABSTRACT FROM AUTHOR]

Currently, bio-natural injectable hydrogels are receiving a lot of attention due to their ability to control, adjust, and adapt to random bone defects, in addition, to their ability to mimic the composition of natural bones. From such a viewpoint, this study goal is to prepare and characterize the injectable hydrogels paste based on the natural alginate (Alg) derived from brown sea algae as a polysaccharide polymer, which coupled with nano biogenic-hydroxyapatite (n-HA) prepared from eggshells and enriched with valuable trace elements. The viscosity and mechanical properties of the paste were investigated. As well as the in-vitro study in terms of water absorption and biodegradability in the PBS, biocompatibility and the capability of the injectable Alginate/n-Hydroxyapatite (Alg/n-HA) to regenerate bone for the most suitable injectable form. The injectable hydrogel (BP -B sample) was chosen for the study as it had an appropriate setting time for injecting (13 mins), and suitable compressive strength reached 6.3 MPa. The in vivo study was also carried out including a post-surgery follow-up test of the newly formed bone (NB) in the defect area after 10 and 20 weeks using different techniques such as (SEM/EDX) and histological analysis, the density of the newly formed bone by Dual x-ray absorptiometry (DEXA), blood biochemistry and the radiology test. The results proved that the injectable hydrogels Alginate/n-Hydroxyapatite (Alg/n-HA) had an appreciated biodegradability and bioactivity, which allow the progress of angiogenesis, endochondral ossification, and osteogenesis throughout the defect area, which positively impacts the healing time and ensures the full restoration for the well-mature bone tissue that similar to the natural bone., Competing Interests: Declaration of competing interest The authors declare that there is no conflict of interest., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Biogenic bioceramics scaffolds are receiving considerable attention for bone restoration applications. Compared with scaffolds of chemical origin, biogenic scaffolds exhibit greater biocompatibility and enhanced bioactive features. In the present study, porous biogenic hydroxyapatite (bHA) was prepared via a polymeric infiltration route and was subsequently coated with alginate to produce alginate/biogenic hydroxyapatite (Alg/bHA) composites. Alginate was used to enhance the mechanical properties as well as the bioactivity and biodegradability of the HA scaffolds. A coating of 3%w/v alginate applied for 10 min was found to result in the best coating for the HA porous scaffolds. The in vitro study demonstrated that the prepared composites had acceptable bioactivity and biodegradability characteristics. The histological study in femur bone of rats indicated that the 3Alg/HA scaffolds capable of supporting both endochondral and intramembranous bone formation. The defect was fully regenerated and mostly filled with the mature lamellar bone after 6 months, with Ca/P atomic ratio similar to the rat's normal bone. The studied scaffolds provide a promising therapeutic option to enhance local bone healing because they do not damage liver or kidney functions and do not induce carcinogenic or inflammatory effects. Accordingly, 3Alg/HA scaffolds are recommended for the tissue engineering applications., (Copyright © 2020 Elsevier B.V. All rights reserved.)