22-03-2011, 02:34 PM
Presented by:
Dipak subedi
[attachment=10747]
UNDERSTANDING SIZE
1 nanometer
SO WHAT IS IT?
Anything smaller than Molecular technology
Size of nanoscale
Every atom in the right place
What makes work at the nanolevel more than just a natural progression of earlier
work at the micro and macro levels of matter? For one thing the basic building blocks of
matter and life occur at the nanolevel. Molecular chemistry, genetic reproduction,
cellular processes, and the current frontier of electronics all occur on the nanolevel.
An explanation
All of u must have operated a digital camera.
U must have noticed when u r shooting a moving picture u sometimes miss some part of it.
Why is it so?
It is because some of the valuable time is wasted in saving the pic just shot..
Now imagine a digital camera which doesn’t incur any of the following time waste..
This is possible if the flash disk that we r using can be replaced by RAM..
But we know that a ram is a volatile memory and everything gets deleted when it is switched off..
So what's the solution ?
Before finding the solution let us discuss something about computers..
All of u know what is booting: it is a process in which the operating system gets loaded in the active memory or the RAM..
We all know that most of the time is wasted while the ram accesses the secondary memory for the information's it needs. So how can we reduce this time..
Also due to the volatile nature of the RAM there is need of the backup power…
The solution is :a non-volatile and durable computer memory that can be erased and reprogrammed electronically.
Can this thing be achieved any time?
The answer to all our problem is nanotechnology..
The use of phase memory
Phase-change memory (also known as PCM,) is a type of non-volatile computer memory. PRAM uses the unique behavior of chalcogenide glass, which can be "switched" between two states, crystalline and amorphous, with the application of heat. Recent versions can achieve two additional distinct states, effectively doubling its storage capacity.
PRAM is one of a number of new memory technologies that are attempting to compete in the non-volatile role with the almost universal Flash memory, which has a number of practical problems these replacements hope to address.
The crystalline and amorphous states of chalcogenide glass have dramatically different electrical resistivity, and this forms the basis by which data are stored. The amorphous, high resistance state is used to represent a binary 0, and the crystalline, low resistance state represents a 1.
Failures of phase change memory
First of all till now the discovery of such materials which are stable to be used as phase change materials has not been found..
Moreover there is a high power required in changing the phase of such materials…
Thus the phase change memory fails..
Is this the end …
Can we hope that the moore law has failed
The moore law claimed that the computers performance will be doubled every 18 to 24 months..
The best is yet to come…
Self-assembled phase-change nanowires, as claimed to be created by Penn researchers, operate with less power and are easier to scale, providing a useful new strategy for ideal memory that provides efficient and durable control of memory
Nanotechnology researchers go ballistic over graphene.
Next generation computer memory made of graphene..
Carbon comes in many different forms, from the graphite found in pencils to the world's most expensive diamonds. In 1980, we knew of only three basic forms of carbon, namely diamond, graphite, and amorphous carbon. Then, fullerenes and carbon nanotubes were discovered and more recently there has been a lot of buzz about graphene.
What is graphene?
Discovered only in 2004, graphene is a flat one-atom thick sheet of carbon. Existing forms of carbon basically consist of sheets of graphene, either bonded on top of each other to form a solid material like graphite, rolled up into carbon nanotubes
Despite being isolated only three years ago, graphene has already appeared in hundreds of papers. The reason scientists are so excited is that two-dimensional crystals (it's called 2D because it extends in only two dimensions - length and width; as the material is only one atom thick, the third dimension, height, is considered to be zero) open up a whole new class of materials with novel electronic, optical and mechanical properties.
The researchers have already gone crazy about this 2d structure..
But we have to wait and watch till this 2d structure makes a revolution in the era of nanotechnology…
CONCLUSION
Improvements and developments in existing products, such as stronger and lighter materials.
Potential to initiate completely new products and industries that do not exist today
OBSTACLES
• Fragile and unstable nature of nanoparticles
• Fusing together of nano particles when their surfaces touch
• Loss of special shape and properties
Dipak subedi
[attachment=10747]
UNDERSTANDING SIZE
1 nanometer
SO WHAT IS IT?
Anything smaller than Molecular technology
Size of nanoscale
Every atom in the right place
What makes work at the nanolevel more than just a natural progression of earlier
work at the micro and macro levels of matter? For one thing the basic building blocks of
matter and life occur at the nanolevel. Molecular chemistry, genetic reproduction,
cellular processes, and the current frontier of electronics all occur on the nanolevel.
An explanation
All of u must have operated a digital camera.
U must have noticed when u r shooting a moving picture u sometimes miss some part of it.
Why is it so?
It is because some of the valuable time is wasted in saving the pic just shot..
Now imagine a digital camera which doesn’t incur any of the following time waste..
This is possible if the flash disk that we r using can be replaced by RAM..
But we know that a ram is a volatile memory and everything gets deleted when it is switched off..
So what's the solution ?
Before finding the solution let us discuss something about computers..
All of u know what is booting: it is a process in which the operating system gets loaded in the active memory or the RAM..
We all know that most of the time is wasted while the ram accesses the secondary memory for the information's it needs. So how can we reduce this time..
Also due to the volatile nature of the RAM there is need of the backup power…
The solution is :a non-volatile and durable computer memory that can be erased and reprogrammed electronically.
Can this thing be achieved any time?
The answer to all our problem is nanotechnology..
The use of phase memory
Phase-change memory (also known as PCM,) is a type of non-volatile computer memory. PRAM uses the unique behavior of chalcogenide glass, which can be "switched" between two states, crystalline and amorphous, with the application of heat. Recent versions can achieve two additional distinct states, effectively doubling its storage capacity.
PRAM is one of a number of new memory technologies that are attempting to compete in the non-volatile role with the almost universal Flash memory, which has a number of practical problems these replacements hope to address.
The crystalline and amorphous states of chalcogenide glass have dramatically different electrical resistivity, and this forms the basis by which data are stored. The amorphous, high resistance state is used to represent a binary 0, and the crystalline, low resistance state represents a 1.
Failures of phase change memory
First of all till now the discovery of such materials which are stable to be used as phase change materials has not been found..
Moreover there is a high power required in changing the phase of such materials…
Thus the phase change memory fails..
Is this the end …
Can we hope that the moore law has failed
The moore law claimed that the computers performance will be doubled every 18 to 24 months..
The best is yet to come…
Self-assembled phase-change nanowires, as claimed to be created by Penn researchers, operate with less power and are easier to scale, providing a useful new strategy for ideal memory that provides efficient and durable control of memory
Nanotechnology researchers go ballistic over graphene.
Next generation computer memory made of graphene..
Carbon comes in many different forms, from the graphite found in pencils to the world's most expensive diamonds. In 1980, we knew of only three basic forms of carbon, namely diamond, graphite, and amorphous carbon. Then, fullerenes and carbon nanotubes were discovered and more recently there has been a lot of buzz about graphene.
What is graphene?
Discovered only in 2004, graphene is a flat one-atom thick sheet of carbon. Existing forms of carbon basically consist of sheets of graphene, either bonded on top of each other to form a solid material like graphite, rolled up into carbon nanotubes
Despite being isolated only three years ago, graphene has already appeared in hundreds of papers. The reason scientists are so excited is that two-dimensional crystals (it's called 2D because it extends in only two dimensions - length and width; as the material is only one atom thick, the third dimension, height, is considered to be zero) open up a whole new class of materials with novel electronic, optical and mechanical properties.
The researchers have already gone crazy about this 2d structure..
But we have to wait and watch till this 2d structure makes a revolution in the era of nanotechnology…
CONCLUSION
Improvements and developments in existing products, such as stronger and lighter materials.
Potential to initiate completely new products and industries that do not exist today
OBSTACLES
• Fragile and unstable nature of nanoparticles
• Fusing together of nano particles when their surfaces touch
• Loss of special shape and properties
