The branch of technology that deals with dimensions and tolerances of less than 100 nanometres, especially the manipulation of individual atoms and molecules in every field of life.

1. NanoTechnology
Shahrbano……#58

2. Introduction:-
 Nanoscience primarily deals with synthesis, characterization, exploration, and
exploitation of nanostructured materials.
 These materials are characterized by at least one dimension in the nanometer
range.
 A nanometer (nm) is one billionth of a meter, or 10–9 m. One nanometer is
approximately the length equivalent to 10 hydrogen or 5 silicon atoms aligned in
a line.
 The processing, structure and properties of materials with grain size in the tens to
several hundreds of nanometer range are research areas of considerable interest
over the past years.
 Although nanotechnology is a new area of research, nanomaterials are known to
be used for centeries.

3. Nanotechnology:-
 Nanotechnology therefore is the complex interdisciplinary science including:
 Nanochemistry (nanocolloid, sol-gel and quantum chemistry) destined for
self- assembling and synthesis of nanoparticles.
 Nanophysics (quantum physics, spintronics, photonics) destined for artificial
assempling and fabrication of nanostructures.
 Nanomaterials science (nanopowder technology, nanoceramics compounds,
nano- tribology, nanosintering and other nanoprocesses) destined for research,
development and production of novel nanostructured architectures.

4. Classification of nanostructure
Gleiter classification:-
 The first category comprises materials and/or devices with reduced
dimensions in the form of isolated, substrate-supported or embedded
nanometer-sized particles, thin wires or thin films.
Techniques
 chemical vapor deposition (CVD),
 physical vapor deposition (PVD),
 various aerosol techniques,
 precipitation from the vapor,
 supersaturated liquids or solids.
.

5. Classification by Dimensionality
 Nanostructures (NSs) should be separated from NSMs because the former
(NSs) are characterized by a form and dimensionality while the last (NSMs) by
a composition in addition.
NSs should be classified :-
 Sign
 Namely
 Dimensionally
 Natural attribute,
 Integrated a size
 shape or form

6. Nanostructred Material
 Nanostructured materials (NSM) have their own peculiar characteristic
distinguished them from the bulk macroscopic 3D materials.
 NSM contain a higher fraction of grain boundary volume
 In nanocrystals, the elastic strain energy is reduced.
 In nanocrystalline alloy of silver – iron (Ag – Fe), there exist a mixture of
nanometer-sized Ag and Fe crystals.
 As the system size decreases, the allowed energy bands become substantially
narrower than in an infinite solid.

7. Fundamental issues:-
 Ability to control the scale of the system.
 Ability to obtain the required composition,not just the average composition but
detail such as defects concentration gradient
 Ability to control the modulation dimensionally.
Future Development:-
 Development of synthesis or fabrication method for raw materials.
 Development of concepts for Nanostructured materials and their elaboration.
 Investigation of catalytic applications of mono and plurimettalic nanomaterials.

8. Interest in nanomaterials:-
 Nanophase ceramics are of particular interest because they are more ductile at
elevated temp.
 Nanosized metallic powder have been used for production of gas tight
materials dense part and porous coating
 Nanostructred semiconductor show various non linear optical properties.
 Nanostructred semiconductor are used as window layer in solar cells.

9. Applications:-
Property
 Bulk:-
 Single magnetic domain
 Small mean free path of eletrons in
a solid
Surface:-
 Large surface area
 Small heat capacity
Application
 Magnetic recording
 Special conductor
 Catalysis sensors
 Heat exchange materials
Combustion,catalysts

10. Applications
Nanotechnology is very advance technique and used in
 Medicines
 Agriculture
 Fertilizers
 Electronics
 Transport
 Materials
 Industries

11. Refrences
 C.M.Rico,S.Majumvar,M.Duarte-Gardea,J.R.Peralta-Videa,and J.L.Gardea-
Torresdy, Interaction of Nanoparticles with Adible plants and Possible
implication in food chain.,Journals of agriculture and Food
chemistry,vol.59,no.8,
 K.K.Kim,H.S.Kim,D.K.Hwang,.J.H.Lim,and
S.J.Park,Nanostructred,Vol.85,no.10