Wednesday, December 21, 2011

Surface Chemistry

Phase : Homogeneous in chemical composition and physical properties.

The place where two kinds of substances meet is called inter facial layer/surface layer/ interface layer.
This is about 10 - 100 Å thick( 3 dimensional). But here we assume it as a 2D layer.

In the above image alpha and beta are two kinds of liquids.
Interactions at the interface differs from that of interactions in substance alpha or beta. Here interactions between alpha and beta molecules is also present where as in alpha only  alpha molecules interact with each other and in beta only beta molecules interact with each other.
Therefor interface have a different average molecular energy than that of the separate substances.
Because of this if you change the area of the interface the internal energy of the system changes.

* To increase the area of the interface work must be done on the system.
dw = - PdV + ɣdA 
dw : Reversible work done on the system
-PdV : Work on the system to increase volume
ɣdA : Additional work
ɣ : Surface tension
dA : Increment in the area of the interface
                         Force on the piston =  P lxlz - ɣlx
ɣlx : force from surface tension
lx : length of the interface on the piston
                   Pressure on the piston  =  (P lxlz - ɣlx) / lxlz
                                                       = P - (ɣ/lz)
* Surface tension is temperature dependent. 
Guggenheim - Katayama equation :

ɣ0 : Constant for each liquid 
T : Temperature in Kelvin
Tc : Critical Temperature
n : Empirical factor; 11/9 for organic liquids

Critical Temperature is the highest temperature at which liquid-vapour equilibrium can be observed.
When a 3rd substance is dissolved in the system the ɣ value changes.

Sunday, December 18, 2011

Mid semester break

Since we got 2 weeks off for Christmas, I thought of dragging out my Benz from the garage and give it some improvements.

This is so far what I've done. Today gave it some materials, made the front number plate and fog lights.

 That's a print screen of the final outcome.
Still got to make
- Roof
- Separate Doors
- Do something about the chassis
- Add details/materials  to tires
- The steel outline of the roof
- Add wipers and air ventilators 
- Extend the front dents 
- Make better materials

Ahh this will take a lot of time to be completed sigh!


Saturday, December 3, 2011

Malaysian Tour

So I was lucky to have my first flight in a plane ( of course I've flown few other times, from cupboard doors and stairs but not in a real plane). More lucky it was with university rowing crew for Varsity Boat Race on a Sri Lankan Airlines plane :D

That is the view from the plane window before landing at Malaysia.

It was quite an experience, the whole tour. The race was in Malaysia, which meant we could do some nice shopping as well.

But well be it Malaysia, Sri Lanka or United States even, rowing is rowing. So we didn't get much time to shop or travel. Belive it or not we didnt get a chance to go to the world famous Petronas Twin Towers!!

That is a picture of Petronas Twin Towers from far far away at night.

We were staying on the 17th floor of Grand Seasons Hotel in Kuala Lampur, which was a very nice hotel and said to be the tallest hotel in Malaysia. First day we went on KL Monorail to Bukit Bintang the nearest city with all those shopping malls, just to see whats it like, right before the dinner.

Front of Grand Seasons Hotel

Monorail is a small train with a length of two compartment that travels on one rail. They have monorail system in Kuala Lampur. They issue one way tickets which are electronically marked. When you insert the ticket to get to the platform , rotating door in front can be moved and you get the ticket back. But when you go out of the platform the machine keeps the ticket. So basically tickets are reusable.

KL Monorail

A Ticket of KL Monorail

So we were in Malaysia but the the race was at Putrajaya Water Complex, which was more than an hour away. So UTM the university which was organizing the event had to supply all the universities staying at the hotel with buses. Journey to the complex was always tiring and everyone was asleep, journey back was more lively and fun.

Malaysia has highways so even though the time was less the distance travelled was more than that of Sri Lanka ( of course now we have a highway too!) And believe it or not , scenery wise Malaysia has got more beautiful buildings than Sri Lanka. But when you take trees and vegetation I must say I SIMPLY LOVE the few bunch of trees in Colombo rather than acres of trees by the highways from KL to Putrajaya. The diversity in Sri Lanka is so huge you can enjoy looking out of the bus windows in Sri Lanka when you are bored. But if you do that in Malaysia you will get bored to absolute death because for miles and miles they have the same kind of tree and then another kind of tree and that goes for miles and miles. 

Putrajaya is a completely planned city. The water complex is based in the Putrajaya Lake. 

That is the complex from the farther side

You can keep walking/ running an get to the exact opposite side( where the photo was taken from)

From all the races we got through to finals in women's double scull, Men's double scull, and eight as far as I remember. I only rowed in the women's eight which we came 4th in the first round which got us through to repechage  but we only came 3rd so unfortunately we couldn't get into finals.

But hey! Officially we are the first Sri Lankan women's team to row in an eight, because we don't have eights races in Sri Lanka as Beira Lake course which is the mostly used one, is only 1 km long.

Proudly present you the first Sri Lankan women's eight 

Men's eight 

Anyway at the end of the competition we managed to get Bronze medals for women's indoor rowing relay. 

The whole team at the photo shoot

Below are some of nice pics from the tour.

View from the 17th floor, our room

view of the roof top swimming pool of the hotel from another room.

Took this at Bukit Bingtang Plaza. It was Deepawali day.

Plenty of cloths shops there. But all I bought from Malaysia are slippers!!

A bridge over the Putrajaya Lake

Some awesomely beautiful buildings in Malaysia

Chocolate! And sweets!!

Super cool Malaysian boats in racks

Traditional Malaysian Dragon Boats