Related papers: Hierarchical structure and biomineralization in cr…
The crystal structure and chemical bonding of magnetron-sputtering deposited nickel carbide Ni$_{1-x}$C$_{x}$ (0.05$\leq$x$\leq$0.62) thin films have been investigated by high-resolution X-ray diffraction, transmission electron microscopy,…
The structure of amorphous materials has been debated since the 1930's as a binary question: amorphous materials are either Zachariasen continuous random networks (Z-CRNs) or Z-CRNs containing crystallites. It was recently demonstrated,…
Carbon nanotubes and biological filaments each spontaneously assemble into kinked helices, rings, and "tennis racket" shapes due to competition between elastic and interfacial effects. We show that the slender geometry is a more important…
Natural hard composites like human bone possess a combination of strength and toughness that exceeds that of their constituents and of many engineered composites. This augmentation is attributed to their complex hierarchical structure,…
We present TEM images of the interior of metal whiskers (MW) grown on electroplated Sn films. Along with earlier published information, our observations focus on a number of questions, such as why MWs' diameters are in the micron range…
The hardest materials in living organisms are biologically grown crystalline minerals, or biominerals, which are also incredibly fracture-tough. Biomineral mesostructure includes size, shape, spatial arrangement, and crystal orientation of…
Y-type hexaferrite samples Ba2ZnxCo2-xFe12O22 with x = 0, 1 and 2 were prepared from precursors synthesized by the citrate sol-gel auto combustion method. The powders were sintered at 1100{\deg} C for four hours. X-ray diffraction, scanning…
The crystal chemical concept of arrangement and function of layered superconducting materials is supposed. The concept is based on results of our investigation of crystal chemistry of high-temperature superconductors (HTSC) cuprates,…
In many biological materials with a hierarchical structure there is an intriguing and unique mechanism responsible for the 'propagation' of order from the molecular to the nano- or micro-scale level. Here we present a much simpler molecular…
The mineralized collagen fibril is the main building block of hard tissues and it directly affects the macroscopic mechanics of biological tissues such as bone. The mechanical behavior of the fibril itself is determined by its structure:…
Cortical bone is a tough biological material composed of tube-like osteons embedded in the organic matrix surrounded by weak interfaces known as cement lines. The cement lines provide a microstructurally preferable crack path, hence…
Intricate biomineralization processes in molluscs engineer hierarchical structures with meso-, nano-, and atomic architectures that give the final composite material exceptional mechanical strength and optical iridescence on the macroscale.…
A fibrous herringbone-modified helicoidal architecture is identified within the exocuticle of an impact-resistant crustacean appendage. This previously unreported composite microstructure, which features highly textured apatite mineral…
Atomic structure of a mono-dispersive hematite ($\alpha$-Fe$_2$O$_3$) nanocube $(0 1\bar1 2)$ surface was determined with synchrotron X-ray diffraction. The $\alpha$-Fe$_2$O$_3$ nanocubes were prepared through a hydrothermal process and a…
Periodic tilings can store information if individual tiles are decorated to lower their symmetry. Truchet tilings - the broad family of space-filling arrangements of such tiles - offer an efficient mechanism of visual data storage related…
In this study, the structural, electronic and vibrational properties of thinnest possible Cadmium crystal are investigated by performing first-principle calculations. Total energy optimization and dynamic stability calculations reveal that…
Chitin is one of the most abundant biomaterials in nature, with 10^10 tons produced annually as hierarchically organized nanofibril fillers to reinforce the exoskeletons of arthropods. This green and cheap biomaterial has attracted great…
Nanocrystalline metals typically have high fatigue strengths, but low resistance to crack propagation. Amorphous intergranular films are disordered grain boundary complexions that have been shown to delay crack nucleation and slow crack…
The molecular structures of amorphous silica and crystalline quartz are used to predict their intrinsic strength and fracture toughness together with the theoretical strength of silicon dioxide. At the atomic scale, the amorphous silica is…
Intimately connected to the rule of life, chirality remains a long-time fascination in biology, chemistry, physics and materials science. Chiral structures, e.g., nucleic acid and cholesteric phase developed from chiral molecules are common…