Praveenkumar Pallapothu

8 Questions 11 Answers 0 Followers

Questions related from Praveenkumar Pallapothu

Any recent or past work on anti tarnish coating on silver and copper?

I want to know conventional methods available to remove the tarnish as well as prevention methods of tarnish of metals.

12 December 2013 7,670 1 View

Why does a sol-gel coated thin film (fused silica or soda lime glass) reflection change colour?

Immediately after coating I can see one color (from reflection) and after heat treatment some other color (from reflection). Why is that particular color(light) undergoing constructive...

11 November 2013 6,950 14 View

Why refractive index is called as optical constant, but it changes with wavelength?

As wavelength increases, R.I. decreases (generally).

11 November 2013 5,386 3 View

Why does a sol-gel coated solid thin film turn into a porous thin film upon heat treatment?

11 November 2013 3,263 2 View

How does roughness of thin film effect surface properties?

I have deposited a oxide thin film on metal substrate.

10 October 2013 9,742 5 View

How to estimate the thickness of thin film from the light reflected from it?

Just by visual inspection.

10 October 2013 4,824 8 View

How one can estimate the amount of powder extracted by drying sol at room temperature?

Is there any standard ratio to formulate the composition of sol? That is, solvent : precursor : complexing agent. Alkoxide + alcohol + complexing agent (with and without).

10 October 2013 5,152 1 View

What is the role of the complexing agent in sol-gel process?

I have prepared two sols, one with complexing agent and other without complexing agent. Both the sols are stable and transperent, but when deposited films on glass substrate using dip coating, sol...

10 October 2013 3,620 10 View