Solution
David answered on
Dec 23 2021
Define nanotechnology and self-assembly
Nanotechnology is the understanding and control of matter at dimensions of roughly 1 to 100 nanometers or
at molecular scale. Nanotechnology have significant impact on almost all industries and all areas of society like
etter built, longer lasting, cleaner, safer, and smarter products for the home, for communications, for
medicine, for transportation, for agriculture, and for industry in general. Nanotechnology can be used in
military for making far more powerful weapons and tools of surveillance. Thus it represents not only
wonderful benefits for humanity, but also grave risks. Nanotechnology allows making of many high-quality
products at very low cost as well as making new nanofactories at the same low cost and at the same rapid
speed. It is a revolutionary, transformative, powerful, and potentially very dangerous—or beneficial—
technology.
Self-assembly in nanotechnology is a manufacturing method used to construct things at the molecular scale.
Many biological systems use self-assembly to assemble various molecules and structures similiarly in
nanotechnology these procedures are imitated for creating novel molecules with the ability to self-assemble
into supramolecular assemblies. Self-assembly is also called 'bottom-up' manufacturing technique in
nanotechnology.
Knowledge of lengths of scale as it relates to nanotechnology
In nanotechnology the wavelike properties of electrons inside matter are influenced by variations on the
nanometer scale. It is possible to vary fundamental properties of materials (e.g. melting temperature,
magnetization, and charge capacity) without changing the chemical composition by patterning matter on the
nanometer length scale.
Life works at the nanometer scale. The systematic organization of matter on the nanometer length scale is a
key feature of biological systems. Nanotechnology promises to allow us to place artificial components and
assemblies inside cells, and to make new materials using the self-assembly methods of nature.
By virtue of their size, nanoscale components have very high surface areas.
Nanotech in disease diagnostics and treatment (theranostics)
Nanotechnolgy has improved diagnostic techniques to screen for disease. Such screening is required to identify illnesses,
assess risk of disease onset, or determine progression or improvement of disease state for diseases such as cancer,
stroke, Alzheimer’s, or cardiac disease. Nanotechnology may improve the sensitivity, selectivity, speed, cost, and
convenience of diagnosis. Individual biomolecular interactions can be detected by the deflection of a microcantilever,
the red-shifted emission of a gold nanoparticle, or the altered conductance of a nanowire. Nanoscale labeling agents,
such as quantum dots, have numerous advantages to intracellular labeling and visualization. Nanotechnology has
opened up the possibility of other screening strategies as well. These techniques and others can be further developed to
enable enhanced visualization of an a
ay, cell culture, or tumor; be multiplexed to create smaller, denser gene and
protein chips; or be integrated into a handheld nanofluidic device to improve clinical diagnosis of disease.
http:
crnano.org
enefits.htm
http:
crnano.org/dangers.htm
http:
crnano.org/dangers.htm
http:
crnano.org
enefits.htm
Scanning Tunneling Microscopy, function and fundamentals
The STM works by scanning a very sharp metal wire tip over a surface. By
inging the tip very close to the
surface, and by applying an electrical voltage to the tip or sample, we can image the surface at an extremely
small scale – down to resolving individual atoms.
STm works on the quantum mechanical effect of tunneling with the help of which we can see the surface.
Another principle used in STM is piezoelectric effect with the help which we can precisely scan the tip with
angstrom-level control. Lastly, a feedback loop is required, which monitors the tunneling cu
ent and
coordinates the cu
ent and the positioning of the tip.
Piezoelectric materials are used to scan the tip in an STM. A typical piezoelectric material used in STMs is PZT
(Lead Zirconium Titanate). The STM is cabable of acquiring remarkable images on the most extreme scale,
easily resolving atomic structure in the right environments.
Describe, using band diagrams, the difference between a metal, semiconductor and insulator.
Draw a chemistry LCAO diagrams to represent the bonding and anti-bonding o
itals of a
simple molecule and of a metal composed of linearly combined atomic o
itals.
Difference between...