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Nanostructure
A nanostructure is a structure of intermediate size between microscopic and molecular structures. Nanostructural detail is microstructure at nanoscale. In describing nanostructures, it is necessary to differentiate between the number of dimensions in the volume of an object which are on the nanoscale. Nanotextured surfaces have ''one dimension'' on the nanoscale, i.e., only the thickness of the surface of an object is between 0.1 and 100 nm. Nanotubes have ''two dimensions'' on the nanoscale, i.e., the diameter of the tube is between 0.1 and 100 nm; its length can be far more. Finally, spherical nanoparticles have ''three dimensions'' on the nanoscale, i.e., the particle is between 0.1 and 100 nm in each spatial dimension. The terms nanoparticles and ultrafine particles (UFP) are often used synonymously although UFP can reach into the micrometre range. The term ''nanostructure'' is often used when referring to magnetic technology. Nanoscale structure in biolog ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nanostructured Film
A nanostructured film is a film resulting from engineering of nanoscale features, such as dislocations, grain boundaries, defects, or twinning. In contrast to other nanostructures, such as nanoparticles, the film itself may be up to several microns thick, but possesses a large concentration of nanoscale features homogeneously distributed throughout the film. Like other nanomaterials, nanostructured films have sparked much interest as they possess unique properties not found in bulk, non-nanostructured material of the same composition. In particular, nanostructured films have been the subject of recent research due to their superior mechanical properties, including strength, hardness, and corrosion resistance compared to regular films of the same material. Examples of nanostructured films include those produced by grain boundary engineering, such as nano-twinned ultra-fine grain copper, or dual phase nanostructuring, such as crystalline metal and amorphous metallic glass nanocompo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nanocomposite
Nanocomposite is a multiphase solid material where one of the phases has one, two or three dimensions of less than 100 nanometers (nm) or structures having nano-scale repeat distances between the different phases that make up the material. In the broadest sense this definition can include porous media, colloids, gels and copolymers, but is more usually taken to mean the solid combination of a bulk matrix and nano-dimensional phase(s) differing in properties due to dissimilarities in structure and chemistry. The mechanical, electrical, thermal, optical, electrochemical, catalytic properties of the nanocomposite will differ markedly from that of the component materials. Size limits for these effects have been proposed: in Kelly, A, ''Concise encyclopedia of composites materials'', Elsevier Science Ltd, 1994 #<5 nm for catalytic activity #<20 nm for making a hard magnetic material soft #<50 nm for refractive index changes #<100 nm for achieving superparamagnetism, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nanoscopic Scale
Nanotechnology is the manipulation of matter with at least one dimension sized from 1 to 100 nanometers (nm). At this scale, commonly known as the nanoscale, surface area and quantum mechanical effects become important in describing properties of matter. This definition of nanotechnology includes all types of research and technologies that deal with these special properties. It is common to see the plural form "nanotechnologies" as well as "nanoscale technologies" to refer to research and applications whose common trait is scale. An earlier understanding of nanotechnology referred to the particular technological goal of precisely manipulating atoms and molecules for fabricating macroscale products, now referred to as molecular nanotechnology. Nanotechnology defined by scale includes fields of science such as surface science, organic chemistry, molecular biology, semiconductor physics, energy storage, engineering, microfabrication, and molecular engineering. The associated rese ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nanopillar
Nanopillars is an emerging technology within the field of nanostructures. Nanopillars are pillar shaped nanostructures approximately 10 nanometers in diameter that can be grouped together in lattice like arrays. They are a type of metamaterial, which means that nanopillars get their attributes from being grouped into artificially designed structures and not their natural properties. Nanopillars set themselves apart from other nanostructures due to their unique shape. Each nanopillar has a pillar shape at the bottom and a tapered pointy end on top. This shape in combination with nanopillars' ability to be grouped together exhibits many useful properties. Nanopillars have many applications including efficient solar panels, high resolution analysis, and antibacterial surfaces. Applications Solar panels Due to their tapered ends, nanopillars are very efficient at capturing light. Solar collector surfaces coated with nanopillars are three times as efficient as nanowire solar cells. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nanomesh
The nanomesh is an inorganic nanostructured two-dimensional material, similar to graphene. It was discovered in 2003 at the University of Zurich, Switzerland. It consists of a single layer of boron (B) and nitrogen (N) atoms, which forms by self-assembly into a highly regular mesh after high-temperature exposure of a clean rhodium or ruthenium surface to borazine under ultra-high vacuum. The nanomesh looks like an assembly of hexagonal poresIn the literature different words referring to similar concepts can be found. Below is a summary of them: * ''Pores, apertures, holes:'' areas of the nanomesh laying the closest to the underlying substrate due to a strong attraction. They form depressions, which are 0.05 nm deep and have a hexagonal shape. * ''Wires:'' areas of the nanomesh referring to the border of the pores, which lay the farer away to the underlying substrate and therefore represent the upper part of the nanomesh. (see right image) at the nanometer (nm) scale. The distance ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnetic Nanochains
Magnetoelastic filaments are one-dimensional composite structures that exhibit both magnetic and elastic properties. Interest in these materials tends to focus on the ability to precisely control mechanical events using an external magnetic field. Like piezoelectricity materials, they can be used as actuators, but do not need to be physically connected to a power source. The conformations adopted by magnetoelastic filaments are dictated by the competition between its elastic and magnetic properties. Mechanical Behavior Magnetic nanochains Magnetic nanochains are a new class of magnetoresponsive and superparamagnetic nanostructures with highly anisotropic shapes which can be manipulated using magnetic field and magnetic field gradient. Such nanochains consist of self-assembled nanoparticle clusters which are magnetically assembled and fixated into a chain. Among the various linking methods used are silica coating, polyacrylic acid (PAA) coating, tetraethoxysilane condensation, biot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nanocages
Gold nanocages (AuNCs) are gold nanoparticles of size 20–500 nm with a hollow cubic structure and porous walls. They can be synthesized by reacting silver nanoparticles with chloroauric acid ( H Au Cl4) in boiling water. Gold nanocages have been suggested for use in drug delivery, photothermal therapy, and as contrast agents. Origin and development Gold nanocages were first created in 2002 by a group at Washington University, Saint Louis, led by Younan Xia. He developed the idea for the synthesis when he was teaching galvanic replacement in a general chemistry course at the same time as a method for silver nanocube creation via polyol reduction was being developed. Since the invention of AuNCs, research has focused on the development of alternative synthesis strategies for more precise tuning of nanocage structure and properties. Another significant area of nanocage development has been the investigation of their potential applications in photoacoustic tomography, photot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nanowire
file:[email protected], upright=1.2, Crystalline 2×2-atom tin selenide nanowire grown inside a single-wall carbon nanotube (tube diameter ≈1 nm). A nanowire is a nanostructure in the form of a wire with the diameter of the order of a nanometre (10−9 m). More generally, nanowires can be defined as structures that have a thickness or diameter constrained to tens of nanometers or less and an unconstrained length. At these scales, quantum mechanical effects are important—which coined the term "quantum wires". Many different types of nanowires exist, including superconducting (e.g. Yttrium barium copper oxide, YBCO), metallic (e.g. nickel, Ni, platinum, Pt, gold, Au, silver, Ag), semiconducting (e.g. Silicon nanowire, silicon nanowires (SiNWs), indium phosphide, InP, gallium nitride, GaN) and insulating (e.g. Silicon dioxide, SiO2, Titanium dioxide, TiO2). Molecular nanowires are composed of repeating molecular units either organic (e.g. DNA) or inorganic (e.g. Mo6S9−''x'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nanoparticle
A nanoparticle or ultrafine particle is a particle of matter 1 to 100 nanometres (nm) in diameter. The term is sometimes used for larger particles, up to 500 nm, or fibers and tubes that are less than 100 nm in only two directions. At the lowest range, metal particles smaller than 1 nm are usually called atom clusters instead. Nanoparticles are distinguished from microparticles (1-1000 μm), "fine particles" (sized between 100 and 2500 nm), and "coarse particles" (ranging from 2500 to 10,000 nm), because their smaller size drives very different physical or chemical properties, like colloidal properties and ultrafast optical effects or electric properties. Being more subject to the Brownian motion, they usually do not sediment, like colloid, colloidal particles that conversely are usually understood to range from 1 to 1000 nm. Being much smaller than the wavelengths of visible light (400-700 nm), nanoparticles cannot be seen with ordinary ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Self-assembly
Self-assembly is a process in which a disordered system of pre-existing components forms an organized structure or pattern as a consequence of specific, local interactions among the components themselves, without external direction. When the constitutive components are molecules, the process is termed molecular self-assembly. Self-assembly can be classified as either static or dynamic. In ''static'' self-assembly, the ordered state forms as a system approaches equilibrium, reducing its free energy. However, in ''dynamic'' self-assembly, patterns of pre-existing components organized by specific local interactions are not commonly described as "self-assembled" by scientists in the associated disciplines. These structures are better described as " self-organized", although these terms are often used interchangeably. In chemistry and materials science Self-assembly in the classic sense can be defined as ''the spontaneous and reversible organization of molecular units in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nanoring
A nanoring is a cyclic nanostructure with a thickness small enough to be on the nanoscale (10−9 meters). Note that this definition allows the diameter of the ring to be larger than the nanoscale. Overview and history The first nanorings were made of gallium nitride in 2001. Nanorings have been prepared from zinc oxide and cyclo-para-phenylenes as well as porphyrins. Although nanorings may have a diameter on the nanoscale, many of these materials have diameters that are larger than 100 nm, with many nanorings having a diameter on the microscale (10−6 meters). As such, nanorings are considered to be members of a sub-class of nanomaterials called one-dimensional (1-D) nanomaterials. These are nanomaterials in which one of the three physical dimensions in a single unit of the material is on a length scale greater than the nanoscale. Other examples of one-dimensional nanomaterials are nanowires, nanobelts, nanotubes, and nanosheets. Mechanical As with other nanomaterials, na ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
