Increasing uses of engineered nanoparticles (ENPs) in commercial products and industrial applications has eventually resulted to their releases into atmospheric, terrestrial, and aquatic environments. However, knowledge gaps in ENPs toxicity, fate, and behaviour currently limit our ability to quantify risk assessment of materials with nanoscale dimensions, and therefore, the extent of the resul...

THE following comments are directed to the sections (2) ‘‘revisit to the grain growth problems in alumina’’ and (3) grain growth without a liquid phase in the article of concern. The purpose of this comment is to challenge the authors’ assertions and refute the following arguments, namely, first that ‘‘MgO can be considered a very effective grain growth promoter in the sintering of alumina,’’ s...

Egyptian Petroleum Research Institute, Nasr City, Cairo, Egypt. Chemistry department, Faculty of Science, Taif University, KSA. _________________________________________________________________________________________ Nine alumina samples of various modification techniques were subjected to thermal analysis via thermogravimetric analysis (TGA) and differential thermal analysis (DTA), in order t...

Previous studies found that the adhesive resin provided strong adhesion to alloys. Also, the bond durability was improved by oxidation of alloys. In oral, many aciditic substances exist. However, the oxides yielded by oxidation are unstable in aciditic environment. Thereupon, the adhesive resin systems should be studied in aciditic environment. In this study, half of the alloy disks were air-br...

Reactions with alumina and platinum crucibles were studied during the preparation of Bi2Sr2Ca1Cu2Oy “2212” glasses. In particular, reactions with Al2O3 are of interest since alumina is a potential substrate material in applications of this superconductor. Glasses processed using alumina crucibles were completely homogeneous and free of secondary phases although the material contained 2.26 at. %...

This work reports an unexpected oxidation behavior of Cu nanoparticles embedded in porous Al(2)O(3) confinements that are produced by annealing alucone (an organic-inorganic hybrid material) deposited by molecular layer deposition. An oxidation of such encapsulated Cu nanoparticles by annealing in air produces Cu oxide nanoparticles attached to the outer surface of the hollow Al(2)O(3) nanostru...

A series of copolymer nanocomposites based on poly(aniline-co-pyrrole) (PANI-co-PPy) with different contents copper alumina (Cu-Al2O3) nanoparticles were synthesized by benign in situ chemical oxidation polymerization. The structural, thermal transition, and morphological interpretations carried out Fourier-transform infrared spectroscopy (FTIR), x-ray diffraction (XRD), differential scanning c...

The wetting of angular alumina particle preforms by Cu-Sn alloys is investigated by means of pressure infiltration experiments conducted at 1150°C, using a system enabling dynamic and precise measurements of the metal volume injected into the preform. Wetting is quantified in terms of drainage curves, which plot the volume fraction of molten metal in the packed powder preform (also called satur...

This work probes the influence of wetting on pressure infiltration. Pressure/saturation curves for the infiltration of packed F-1000 angular alumina particle preforms by liquid Cu-Al and Sn-Al alloys are measured using an instrumented high-temperature pressure infiltration apparatus. These are ceramic-metal systems in which the contact angle is documented to vary significantly with alloying, fr...