The understanding of the chemical and physical properties of atomic and nanoscale materials.
Materials that result from the intimate mixture of two or more nanophase materials. See composite.
Solids with small domains of crystallinity within the amorphous phase. Applications include optical electronics and solar cells.
Nanoelectromechanical Systems (NEMS)
A generic term to describe nanoscale electrical/mechanical devices.
A polymer membrane formed by electrospinning, with filament diameters of 150–200 nanometers. Also called nanomesh, it is used in air and liquid filtration applications.
The control of nanoscale amounts of fluids.
Writing nanoscale patterns. See Lithography.
The process of manipulating items at an atomic or molecular scale in order to produce precise structures.
Nanoscale particles, films, and composites designed and assembled in controlled ways.
A unit of measurement equal to one-billionth of one meter. The head of a pin is about 1 million nanometers across. A human hair is about 60,000 nanometers in diameter, and a DNA molecule is between 2-12 nanometers wide.
Particles ranging from 1 to 100 nanometers in diameter. Semiconductor nanoparticles up to 20 nanometers in diameter are often called quantum dots, nanocrystals, or Q-particles.
Engineered materials with nanoscale holes, used in filters, sensors, and diffraction gratings. In DNA sequencing, nanoporous materials have tiny holes that allow DNA to pass through one strand at a time. In biology, complex protein assemblies that span cell membranes allow ionic transport across the otherwise impermeable lipid bilayer.
A nanoparticle that has a metallic shell surrounding a semiconductor. Nanoshells are being investigated for use in treating cancer.
Structures made from nanomaterials.
Long, thin cylinders of carbon, discovered in 1991 by S. Iijima. These large macromolecules are unique for their size, shape, and remarkable physical properties. They can be thought of as a sheet of graphite (a hexagonal lattice of carbon) rolled into a cylinder. The physical properties are still being discovered. Nanotubes have a very broad range of electronic, thermal, and structural properties that change depending on the different kinds of nanotube (defined by its diameter, length, and chirality, or twist). To make things more interesting, besides having a single cylindrical wall (Single Walled Nanotubes or SWNTs), nanotubes can have multiple walls (MWNTs)–cylinders inside the other cylinders. Usually referred to as carbon nanotubes, also known as nanorods. Applications for carbon nanotubes include high-density data storage, nanoscale electronics, and flexible solar cells.
NMR (Nuclear Magnetic Resonance) pectroscopy
Analytical technique used to determine the structure of molecules. In NMR, the molecule is placed within a strong magnetic field to align the atomic nuclei. An oscillating electromagnetic field is applied, and the radiation absorbed or emitted by the molecule is measured. Not all atoms can be detected using NMR because the nuclei must have non-zero magnetic moments.
Interactions first recognized by J. D. van der Waals in the nineteenth century. In contrast to the covalent interactions, noncovalent interactions are weak interactions that bind together different kinds of building blocks into supramolecular entities. Also referred to as van der Waals interactions.