There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality.

Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

I and i

Introduction to linear and nonlinear programming

Estimates of genetic and environmental variability in soybeans (Glycine max. L.) [Egypt].

Isocyanate, and Non-isocyanate Polyurethane Etienne Delebecq,† Jean-Pierre Pascault,‡,§ Bernard Boutevin,† and Franco̧is Ganachaud*,†,‡,§ †Institut Charles Gerhardt, UMR 5253 CNRS, Ingeńierie et Architectures Macromolećulaires, Ecole Nationale Supeŕieure de Chimie de Montpellier, 8 rue de l’ećole normale, 34296 Montpellier, Cedex 05, France ‡INSA-Lyon, IMP, UMR5223, F-69621, Villeurbanne, France Universite ́ de Lyon, F-69622, Lyon, France

On the Versatility of Urethane/Urea Bonds: Reversibility, Blocked Isocyanate, and Non-isocyanate Polyurethane

High-Performance Piezoelectric Energy Harvesters and Their Applications

This paper describes the mechanical properties of carbon nanotube-reinforced Al2O3 nanocomposites fabricated by hot-pressing. The results showed that compared with monolithic Al2O3 the fracture toughness, hardness and flexural strength of the nanocomposites were improved by 94%, 13% and 6.4% respectively, at 4 vol.% CNT additions. For 10 vol.% CNT additions, with the exception of the fracture toughness, which was improved by 66%, a decrease in mechanical properties was observed when compared with those for monolithic Al2O3. The toughening mechanism is discussed, which is due to the uniform dispersion of CNTs within the matrix, adequate densification, and proper CNT/matrix interfacial connections.

Carbon nanotube toughened aluminium oxide nanocomposite

Multi-walled carbon nanotubes reinforced Al2O3 nanocomposites: Mechanical properties and interfacial investigations

Ceramics suffer the curse of extreme brittleness and demand new design philosophies and novel concepts of manufacturing to overcome such intrinsic drawbacks, in order to take advantage of most of their excellent properties. This has been one of the foremost challenges for ceramic material experts. Tailoring the ceramics structures at nanometre level has been a leading research frontier; whilst upgrading via reinforcing ceramic matrices with nanomaterials including the latest carbon nanotubes (CNTs) and graphene has now become an eminent practice for advanced applications. Most recently, several new strategies have indeed improved the properties of the ceramics/CNT nanocomposites, such as by tuning with dopants, new dispersions routes and modified sintering methods. The utilisation of graphene in ceramic nanocomposites, either as a solo reinforcement or as a hybrid with CNTs, is the newest development. This article will summarise the recent advances, key difficulties and potential applications of the ceramics nanocomposites reinforced with CNTs and graphene.

https://www.mdpi.com/2079-4991/5/1/90/pdf

Recent Advances on Carbon Nanotubes and Graphene Reinforced Ceramics Nanocomposites.

Alumina nanocomposites reinforced with hybrid GNTs (graphene nanoplatelets, GNPs, and carbon nanotubes, CNTs) were fabricated by hot-pressing. The effects of varied GNT contents on the microstructural features and mechanical properties of the nanocomposites were investigated. The well-dispersed GNT fillers resulted in higher sintered densities (>99%) in the composites, whilst the fracture mode alteration, grain refinement and improved strength and flexibility of the composites are associated with the CNTs and GNPs. The average fracture toughness of the nanocomposites reached up to 5.7 MPa m1/2, against 3.5 MPa m1/2 of the plain alumina, and the flexural strength improved from 360 MPa to 424 MPa, at a hybrid addition of 0.5 wt% GNPs and 1 wt% CNTs. Toughening mechanisms attributed with the unique morphologies and structures of the GNT fillers were also discussed based on analyses on the morphology, grain sizes and fracture mode.

Iftikhar Ahmad

Papers

Carbon nanotube toughened aluminium oxide nanocomposite

Multi-walled carbon nanotubes reinforced Al2O3 nanocomposites: Mechanical properties and interfacial investigations

Recent Advances on Carbon Nanotubes and Graphene Reinforced Ceramics Nanocomposites.

Graphene and carbon nanotube (GNT)-reinforced alumina nanocomposites

Wear resistant properties of multi-walled carbon nanotubes reinforced Al2O3 nanocomposites