Examining the effect of nano-additions of rare earth elements on the hardness of body armor ceramic

64-72Body armor is a very critical entity in protecting soldier's live. Soldiers carry heavy stuff on duties, and the ceramic insert in those body armors is one of them. The purpose of this paper is to investigate the effect of Nano-rare-earth elements as additives to the ceramic base material on the armor's performance. Aluminum oxide (Al2O3) has been selected as the base material of the ceramic in this study. This study has chosen two additives: Zirconium dioxide (ZrO2) and Nano-ceramic lab composite (NCLC). In this work, we have presented results of mechanical characterization for alumina-nanocomposites armor plates. Three different concentrations of NCLC and ZnO2 alumina-based compositions have been prepared and pressed at 40 and 50 MPa and sintered at 1350°C for 120 min. X-ray diffraction and scanning electron microscopy (SEM) techniques have been employed to characterize structural, morphological, and phase identification of the films. Mohs test hardness measurements of samples after sintering have been performed. Results have shown that the compositions with NCLC showed a higher hardness than a composition with ZrO2. This result has indicated that the addition of NCLC to Alumina enhances the microstructure and increases the ceramics' hardness

Desenvolvimento em VHDL de um processador para suporte nativo aos bytecodes da linguagem Python

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Desenvolvimento em VHDL de um processador para suporte nativo aos bytecodes da linguagem Python

1

Examining the effect of nano-additions of rare earth elements on the hardness of body armor ceramic

Body armor is a very critical entity in protecting soldier's live. Soldiers carry heavy stuff on duties, and the ceramic insert in those body armors is one of them. The purpose of this paper is to investigate the effect of Nano-rare-earth elements as additives to the ceramic base material on the armor's performance. Aluminum oxide (Al2O3) has been selected as the base material of the ceramic in this study. This study has chosen two additives: Zirconium dioxide (ZrO2) and Nano-ceramic lab composite (NCLC). In this work, we have presented results of mechanical characterization for alumina-nanocomposites armor plates. Three different concentrations of NCLC and ZnO2 alumina-based compositions have been prepared and pressed at 40 and 50 MPa and sintered at 1350°C for 120 min. X-ray diffraction and scanning electron microscopy (SEM) techniques have been employed to characterize structural, morphological, and phase identification of the films. Mohs test hardness measurements of samples after sintering have been performed. Results have shown that the compositions with NCLC showed a higher hardness than a composition with ZrO2. This result has indicated that the addition of NCLC to Alumina enhances the microstructure and increases the ceramics' hardness

Fundamentals and Applications of Chitosan

International audienceChitosan is a biopolymer obtained from chitin, one of the most abundant and renewable material on Earth. Chitin is a primary component of cell walls in fungi, the exoskeletons of arthropods, such as crustaceans, e.g. crabs, lobsters and shrimps, and insects, the radulae of molluscs, cephalopod beaks, and the scales of fish and lissamphibians. The discovery of chitin in 1811 is attributed to Henri Braconnot while the history of chitosan dates back to 1859 with the work of Charles Rouget. The name of chitosan was, however, introduced in 1894 by Felix Hoppe-Seyler. Because of its particular macromolecular structure, biocompatibility, biode-gradability and other intrinsic functional properties, chitosan has attracted major scientific and industrial interests from the late 1970s. Chitosan and its derivatives have practical applications in food industry, agriculture, pharmacy, medicine, cos-metology, textile and paper industries, and chemistry. In the last two decades, chito-san has also received much attention in numerous other fields such as dentistry, ophthalmology, biomedicine and bio-imaging, hygiene and personal care, veterinary medicine, packaging industry, agrochemistry, aquaculture, functional textiles and cosmetotextiles, catalysis, chromatography, beverage industry, photography, wastewater treatment and sludge dewatering, and biotechnology. Nutraceuticals and cosmeceuticals are actually growing markets, and therapeutic and biomedical products should be the next markets in the development of chitosan. Chitosan is also the N. Morin-Crini (*) · Laboratoire Chrono-environnement, UMR 6249, UFR Sciences et Techniques