Strategies for Landing an Oracle DBA Job as a Fresher
Towards an Improved Bead Single Crystal Electrochemistry And Electrocatalysis Laboratory
1. 59th International Conference on Analytical
Sciences and Spectroscopy(ICASS)
Nakkiran Arulmozhi
Electrochemistry and Electrocatalysis Laboratory
Department of Chemistry
Queen’s University
1
2. Motivation
2
“Electro-oxidation of COchem on Pt
Nanosurfaces: Solution of the Peak
Multiplicity Puzzle” - Langmuir, 2012, 28
(7), pp 3658–3663
Electrocatalyst crystal surface is
heterogeneous in nature
Structure-reactivity relationship is
key factor
Rational solution – studies on well
defined structure
Oxide growth and Electrodissolution
studies
Need for improved single crystal lab
4. Bead Crystal Growth– Principle
Melt Growth - Basis
Kinetics Effect
Solidification = nucleation + growth
Temperature
G
GSolid
GLiquid
Tm
Solid Liquid
Ts
ΔT
ΔG
Driving force
for Crystal GrowthThe driving force of Solidification
m
m
a
SolidLiq
a
T
TT
HG
)(
Thermodynamics
ΔT in small steps → uniform nucleation
ΔT in large step → non uniform nucleation
Solid
5. 5
Bead Growth System – Process and Advantage
Temperature Gradient in Flame
Process Parameter
Flow Rate
Mixing Ratio
Speed of flame movement
S/L boundary movement
Controlled (slow) S/L boundary movement
Precise temperature gradient (ΔT )
Requirement
6. 6
Bead Growth System – Improved Design
Set-Up Advantage
• Fully automated
• Min step size (sub
micron)
• Min speed (0.9
micron/sec)
• Precise flow rate
and mixing ratio
control
• Completely stable
and safe
8. 8
Growth Optimization
Bead Diameter Optimization
Weight of the molten drop vs max diameter
rgR 2
3
4 3
max
R- radius of bead : r – radius of wire
µ - mass :σ – surface tension
Zone Refining Cycle Optimization After 20 Cycle
̴ 20 Cycles
Initial Cycle – 0.0125 mm/s Final Cycle – 0.1 mm/s
10. 10
Cost Analysis and Conclusion
Commercial Pt single crystal – more than 1500$
Quick and complete Safe
Physical Understanding
Process Parameter Optimization
No skill requirement (fully automated)
Highly consistent and efficient (optimized process parameter)