Nanotechnology nanostructures

Rotello, V. Nanoparticles Building Blocks for Nanotechnology (Nanostructure Science and Technology), Springer New York, 2004. 

The research of electroless deposition in relation with nanotechnology will definitely be expanded in the future. This process (electroless deposition) can quite successfully produce a variety of nanostructures, which have been known and understood far before the appearance of nanotechnology. Nanostructures produced via electroless deposition may have great potential for various engineering applications in the future. 

Nanotechnology is the branch of engineering that deals with the manipulation of individual atoms, molecules, and systems smaller than 100 nanometers. Two different methods are envisioned for nanotechnology to buUd nanostructured systems, components, and materials. One method is the top-down approach and the other method is called the bottom-up approach. In the top-down approach the idea is to miniaturize the macroscopic structures, components, and systems toward a nanoscale of the same. In the bottom-up approach the atoms and molecules constituting the building blocks are the starting point to build the desired nanostmcture [96-98]. 

The building blocks of all materials in any phase are atoms and molecules. Their arrangements and how they interact with one another define many properties of the material. The nanotechnology MBBs, because of their sizes of a few nanometers, impart to the nanostructures created from them new and possibly preferred properties and characteristics heretofore unavailable in conventional materials and devices. These nanosize building blocks are intermediate in size, lying between atoms and microscopic and macroscopic systems. These building blocks contain a hmited and countable number of atoms. They constitute the basis of our entry into new realms of bottom-up nanotechnology [97, 98]. 

Considering that nanoparticles have much higher specific surface areas, in their assembled forms there are large areas of interfaces. One needs to know in detail not only the structures of these interfaces, but also their local chemistries and the effects of segregation and interaction between MBBs and their surroundings. The knowledge of ways to control nanostructure sizes, size distributions, compositions, and assemblies are important aspects of bottom-up nanotechnology [97]. 

The formation of nanopattemed functional surfaces is a recent topic in nanotechnology. As is widely known, diblock copolymers, which consist of two different types of polymer chains cormected by a chemical bond, have a wide variety of microphase separation structures, such as spheres, cylinders, and lamellae, on the nanoscale, and are expected to be new functional materials with nanostructures. Further modification of the nanostructures is also useful for obtaining new functional materials. In addition, utilization of nanopartides of an organic dye is also a topic of interest in nanotechnology. 

F. Gonella, P. Mazzoldi, Metal nanocluster composite glasses, in H. S. Nalwa (ed.) Handbook of Nanostructured Materials and Nanotechnology, Vol. 4, Academic Press, San Diego, 2000, 82. 

This series will cover the wide ranging areas of Nanoscience and Nanotechnology. In particular, the series will provide a comprehensive source of information on research associated with nanostructured materials and miniaturised lab on a chip technologies. 

Stang, P. J. Olenyuk, B. Transition-metal-mediated self assembly of discrete manoscopic species with well-defined structures and shapes. In Handbook of Nanostructured Materials and Nanotechnology, Nalwa, H. S.. Ed. Academic Press San Deigo, 2000, Vol. 5, 167-224. 

Perfection of Structure in Nanostructured Materials. An aim of modern nanotechnology is the fabrication of materials with highly perfect structure on the nanometer scale. The distortion of such nanostructured materials can be studied by SAXS methods. Frequently the material is supplied as a very thin film with predominantly uniaxial correlation among the nanodomains. Under these constraints the nanodomains are frequently arranged in such a way that the normal to the film is a symmetry axis rotation of the film on the sample table does not change the scattering (fiber symmetry). 

Nucleic acids, DNA and RNA, are attractive biopolymers that can be used for biomedical applications [175,176], nanostructure fabrication [177,178], computing [179,180], and materials for electron-conduction [181,182]. Immobilization of DNA and RNA in well-defined nanostructures would be one of the most unique subjects in current nanotechnology. Unfortunately, a silica surface cannot usually adsorb duplex DNA in aqueous solution due to the electrostatic repulsion between the silica surface and polyanionic DNA. However, Fujiwara et al. recently found that duplex DNA in protonated phosphoric acid form can adsorb on mesoporous silicates, even in low-salt aqueous solution [183]. The DNA adsorption behavior depended much on the pore size of the mesoporous silica. Plausible models of DNA accommodation in mesopore silica channels are depicted in Figure 4.20. Inclusion of duplex DNA in mesoporous silicates with larger pores, around 3.8 nm diameter, would be accompanied by the formation of four water monolayers on the silica surface of the mesoporous inner channel (Figure 4.20A), where sufficient quantities of Si—OH groups remained after solvent extraction of the template (not by calcination). 

One-dimensional (ID) nanostructures have also been the focus of extensive studies because of their unique physical properties and potential to revolutionize broad areas of nanotechnology. First, ID nanostructures represent the smallest dimension structure that can efficiently transport electrical carriers and, thus, are ideally suited for the ubiquitous task of moving and routing charges (information) in nanoscale electronics and optoelectronics. Second, ID nanostructures can also exhibit a critical device function and thus can be exploited as both the wiring and device elements in architectures for functional nanosystems.20 In this regard, two material classes, carbon nanotubes2131 and semiconductor nanowires,32"42 have shown particular promise. 

The study of principles relevant to building nanoscale structures of, for example, 1-100 nm in size has recently been referred to as nanoscience, and it is expected that methods for the fabrication of nanostructures will evolve into nanotechnologies. The present approach toward a nanochemistry is of more fundamental character since it is restricted to single molecules of a few nm in size or even smaller and focuses on the molecular pattern. 

Carbon monoxide off-gas, from phosphorus manufacture, 19 12 Carbon nanostructures, 27 46-58 Carbon Nanotechnologies, Inc., 2 718, 719 Carbon-nanotube fibers, 23 385-386 Carbon nanotubes (CNTs), 2 655, 693, 694, 719-722 20 434 27 47 8 ... 

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