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Science communication is important in today's technologically advanced society. A good part of the adult community is not science saavy and lacks the background to make sense of rapidly changing technology. My blog attempts to help by publishing articles of general interest in an easy to read and understand format without using mathematics. I also give free lectures in community events - you can arrange these by writing to me.

Saturday, 17 September 2011

NanoTechnology Talks - October 2011

Nanotechnology is best understood as a convergence of many technologies -
material sciences, physics, life sciences, chemistry, electrical engineering, computer science, information technology, medicine - every discipline is impacted by nanotechlogy.

In the five 90-minute talks, I had to choose my material very carefully
to provide a good comprehensive feel for the subject.
I have prepared a list of topics that
I shall be discussing in the talks starting Saturday 1st October in the lovely
lecture theatre in James Watt Building, East Kilbride Technology Park.

Talk 1: Introduction and Nanoparticles
Recent trends in technologies
Nano means dwarf; scale of things
Nano-objects behave differently
Reactivity is skin deep
Nano particles and enormous surface area
Some current examples of nanoparticles in use
Nanoparticles are good catalysts
Zeolites – molecular sieves

Talk 2: Seeing Nano Objects
Types of microscopes
Optical microscopes
Wave nature of the electron
Magnetic lens
Electron microscopes
Quantum tunnelling effect
Scanning tunnelling microscope
Atomic force microscope
Examples of images of nanostructures

Talk 3: Making Nano Objects; The digital Revolution
Shrinking device sizes
Top-down and bottom-up Manufacturing
Self assembly
The information Technology Revolution – historical
Transistor and Integrated Circuit
Moore’s first and second laws – trends and limits
About robots
Examples: Nuclear plant safety, Electronic noses

Talk 4: Nature’s Nanotechnology
What has nature given us?
Artificial leaf
DNA – the molecule of life
Watson and Crick model of the DNA
Genes - coding for proteins; How Many? Junk DNA
Making new software for the cell
Recombinant DNA Technology
Learning from Nature’s achievements

Talk 5: The Story of Carbon; Nanomedicine
Many forms of carbon
Graphite and graphene
Bucky Balls – what are they and some applications
Carbon nanotubes – what are they and some applications
The space elevator
Miniature computers
Probing the cell with nanoprobes
Computerised Tomography with nanotube X-ray source
Photodynamic therapy
Nanotechnology and cancer diagnosis and treatment
Nanoparticles and Enhanced permeability and retention effect (EPR effect)
Nanoshells in cancer detection
PEBBLES – a remarkable feat of nanotechnology
Concluding Remarks

Wednesday, 14 September 2011

The Scale of the Universe

Humans occupy an average middle place in the scheme of things. 
There are vastly bigger entities and vastly smaller ones at the other end. 
Our senses only allow us to see and feel things that are within a few order of magnitudes in size relative to us. 
It is only in the past 200 years or less that we have been able to comprehend the vastness of space and that is where the wonderful website HTWINS gives us a glimpse of what lies beyond our limited perception.

HTWINS is wonderfully presented and graphically describes the enormous range of objects in our Universe.The only way to appreciate it is to open the link and play with it for a few minutes.


It is almost impossible not to be impressed by it. ENJOY!

Friday, 12 August 2011

You have enough DNA to circle the Earth 4 million times!!

Unbelievable - each of us has enough DNA to circle the Earth 4 million times.

This is how it works:

If stretched, DNA in a single cell will extend to 1.5 metres**

A cell is typically 10 microns (1 micron = 10-6 m) across
Volume of a cell is of the order of 10-15 m3

Consider a 100 kg man with density equal to that of water (1000 kg/m3)
Volume of the person is 0.1 m3 (volume = mass/density)

Therefore, there are 1014 cells - this is 100,000 billion cells and
the length of the DNA is 150 billion km

This is sufficient to circle the Earth 4 million times!

** Human Genome Project has mapped 3 billion base-pairs in a human DNA. If base-pairs are 0.5 nm apart then the stretched DNA would be 1.5 m long.
Earth's circumference is about 40,000 km