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What is the current state of nanoscience and nanotechnology?Current knowledge in nanoscience comes from developments in chemistry, physics, life sciences, medicine, and engineering. Nanotechnology is under active development or already in practical use in several areas:In materials science, nanoparticles allow for the making of products with new mechanical properties, including surface friction, wear resistance, and adhesion.The smallest components of a computer chip are on a nanoscale.The smallest components of a computer chip are on a nanoscale.Credit: NanoPrism Technologies, Inc.In biology and medicine, nanomaterials are used to improve drug design and targeting. Others are being developed for analytical and instrumental applications.Consumer products such as cosmetics, sunscreens, fibres, textiles, dyes, and paints already contain nanoparticles.In electronic engineering, nanotechnologies are used for instance to design smaller, faster, and less consuming data storage devices.Optical devices such as microscopes have also benefited from nanotechnology. Current knowledge of science at the nanoscale comes from developments in disciplines such as chemistry, physics, life sciences, medicine and engineering. There are several areas in which nanoscale structures are under active development or already in practical use:In materials science, nanoparticles allow for the making of products with mechanical properties very different from those of conventional materials and can also improve surfaces by adding new friction, wear or adhesion properties.In biology and medicine, a greater understanding of the functioning of molecules and of the origin of diseases on the nanometre scale has lead to improvements in drug design and targeting. Nanomaterials are also being developed for analytical and instrumental applications, including tissue engineering and imaging.A wide variety of nanoscale materials and coatings are already in use in consumer products such as cosmetics and sunscreens, fibres and textiles, dyes, and paints.The smallest components of a computer chip are on a nanoscale.The smallest components of a computer chip are on a nanoscale.Credit: NanoPrism Technologies, Inc.The constant drive towards miniaturization in electronic engineering has led to devices that are well within the nanometre range. Data storage devices based on nanostructures provide smaller, faster, and lower consumption systems.Optical devices have also benefited from this trend and new types of microscopes have been invented, that can produce images of atomic and molecular processes at surfaces. More... 3.3 Nanoscience and Nanotechnology 3.3.1 Introduction Current knowledge of science at the nanometre scale is derived from many disciplines, originating with the atomic and molecular concepts in chemistry and physics, and then incorporating molecular life sciences, medicine and engineering. The observation and understanding of atomic and molecular behaviour from first principles was followed by the increasing ability to control and selectively modify properties of ever smaller pieces of matter in a functional way. Early examples here are the discoveries in self assembly (Bain et al 1989) which culminated in current synthetic and supra-molecular chemistry (Lehn 1988, Gomez –Lopez et al 1996), the increasing knowledge about life’s replication processes and the co-evolution of physical (Perutz et al 1960, Aue et al 1976, Wuthrich 1995) and chemical methodologies. These have resulted in the portfolio of current molecular life sciences such as molecular motors and other functional entities (Mavroidis et al 2004, Clark et al 2004), including biomolecular and medical engineering and the emerging area of systems biology. On the other hand, man made micro and nanoscale sensing devices originate from other domains in microscopy and device engineering but relate to biomedical applications (Ziegler 2004, Emerich and Thanos 2003). The deviation of surface and interface properties from the bulk properties of larger amounts of materials led to the sometimes unexpected significance of surface effects, including catalytic activity and wetting behaviour in material composed of nanosized entities, such as nanoparticles, composites and colloids (Kamat 2002, Schwerdtfeger 2003). Quantum mechanical principles manifest themselves in the properties of surfaces of clusters of very small particles, especially those of the order of 1000 atoms or molecules and less. Composite materials (Komarneni 1992, Schmidt 2000, Hadjipanayis 1999), with increasingly smaller characteristic sizes of the domains or phases, allowed for the design of materials with new and optimised physical and / or chemical properties. In electronic engineering, the miniaturization of devices has progressed well into the nanometre range with gate oxides in devices being routinely 25 nm thick. The recently increased public awareness of nanoscience is closely related to the availability of first real space images of atomic and molecular processes at surfaces through the invention of Scanning Probe Microscopies (Binnig and Rohrer 1985). With the continuous development of nanotechnology, the possibility for the bottom-up production of nanoscale materials may result in some kind of self assembly of structures similar to the self assembly of phospholipid bilayers that resembles cellular membranes. On the basis of current knowledge however, the spontaneous formation of artificial living systems through self assembly and related processes, suggested by some prominent commentators, is considered highly improbable. The combination of self replication with self perpetuation in an engineered nanosystem is extremely difficult to realize on the basis of current scientific knowledge. 3.3.2 Examples of Engineered Nanostructures and Materials and Their Applications There are several areas of science and technology in which nanoscale structures are under active development or already in practical use.
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