nuclear techniques in material sciences: the ion beam laboratory coordinator: eduardo alves mission:...
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Nuclear Techniques in Material Sciences:The Ion Beam Laboratory
Coordinator: Eduardo Alves
Mission:
National facility to provide the Scientific and Industrial
communities with unique ion beam processes for material
characterization and modification.
Strategy:Continue and expand expertise into new areas with particular emphasis on:
• Development of new materials for optoelectronic and magneto-optic applications;• Nanotechonologies and Advanced materials;• Biomedical and Health applications;• Environmental applications;• Art and Archaeometry;• Geosciences. E. Alves, NuPECC Meeting (Lisbon 2004)
Where we are.....
E. Alves, NuPECC Meeting (Lisbon 2004)
The Site
E. Alves, NuPECC Meeting (Lisbon 2004)
2.5 MV Van de Graaff
PIXE/NRA
RBS-CERDA
IONImplantation
-probe
The Laboratory
E. Alves, NuPECC Meeting (Lisbon 2004)
The Groups (ITN/CFNUL)
External Users
Materials Science
Applications
Nuclear MicroProbe Applications
Materials, Art and
Arqueometry Luís C. Alves
Rui C. SilvaMárcia Vilarigues
(PhD Student)
Health and BiologyTeresa PinheiroPatrícia Napoleão (PhD student)Carlos Monteiro (PhD student)Ana Veríssimo (Fellowship)Micaela Amim (MsC student)Inês Batista (Lic. student)
Eduardo AlvesRui Coelho da Silva
Luís C. AlvesNuno Barradas(20%)
Ana Rita Ramos(20%)Katharina Lorenz (Post
Doc)Vitória Corregidor (Post
Doc)Joana V. Pinto (PhD
student)Carlos Marques (PhD
student)Elisabete Rita (PhD
student)Alexandra Fonseca (PhD
Student)Users and Collaborators
Mark BreeseCarl McHargue
Manuel Ribeiro da SilvaLuís RedondoAndreas Kling
João Guilherme CorreiaUli Whal (Postdoc)
Experimental Nuclear Reactions
Adelaide de Jesus (Fac. of Sci. and Tech.)
João Pires Ribeiro( Faculty of Sciences)
João Cruz (PhD student)Bruno Braizinha (PhD student)
Elemental SpeciationMiguel Reis
Paula Cristina (PhD Student)
Technical staff J. Rocha F. Baptista R. Pinheiro P. Pereira
CollaboratorsMaria Cristina Santos (FC-UL)Ana Viegas-Crespo (FC-UL)Paulo Filipe (FM-UL)J. Silva FM-UL (PhD student)Raquel Silva (FM-UL)Bugalho de Almeida (FM-UL)
Max.
Min.
2640
µm
Max.
Min.SiSEI
Materials for Fusion reactors
Art
Nuclear Microprobe
Human pathologies (metabolism)Skin permeability
Impurity content & chemical compatibility
Stained glass & paint structure
Mineralogy
Elemental zonation
Biomedicine
Photo
V Fe
Ti
Max.
Min.
Fe
Pb Zn
Photo
E. Alves, NuPECC Meeting (Lisbon 2004)
Cell resolution capabilities
Modification of electronic, optical, electrical, magnetic properties– defects, dopant levels, structure
Metals and alloys
Direct compound formation – surface alloying– corrosion & tribology
Oxides and semiconductors
IBAIon Beam Analysis
characterization
Lattice Site locationIon
Implantation
New Materials
Number and individual composition,thickness and extent of intermixing
Quantum dots and multilayers
300 400 500 600 700 800 900 10000.0
0.5
1.0
1.5
2.0g(HL)8Ha multilayer coating
E = 2.5 MeV
coun
ts (/
103 )
channel number
H L H L H L H L H L H L H L H L H0
100
200
300
400
thic
knes
s (n
m)
layer type
400 500 600 700 800 9000.0
0.5
1.0
1.5
2.0
abso
rptio
n (a
.u.)
wavelength (nm)
GaN
<0001>
<1011>
0.0
0.2
0.4
0.6
0.8
1.0
1.2
<0001>
Ga Er
norm
aliz
ed y
ield
-3 -2 -1 0 1 2 3
0.2
0.4
0.6
0.8
1.0
1.2
Ga N
angle(deg.)
<1011>
norm
aliz
ed y
ield
Materials Science
Human Health and Biomedical StudiesAlteration of plasma Se concentration and oxidation markers
in COPD patients
Skin Fe correlates with plasma Fe content in heamochromatosis patients
200 400 600 800 1000120014001.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
0 200 400 600 800 1000120014001.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
Pla
sma
Fe
(g
/ml)
Epidermal Fe (g/g dw)
Regression and 95% confidence limits[Plasma Fe] = 1.6 + 0.002 x [Epidermal Fe]; r=0.91, p<0.03
min max
scep FeSTIM
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
Pro
tein
Ca
rbo
ny
ls (
nm
ol/
mg
)
Controls PatientsSmokersEx-smokers
P<0.01
P<0.01
0.00
0.02
0.04
0.06
0.08
0.10
P<0.01
P<0.05
Se
(m
g/L
)
Controls PatientsSmokersEx-smokers
E. Alves, NuPECC Meeting (Lisbon 2004)
• Environmental applications– Aerosol samples
– Biomonitoring samples
– Uptake modelling
• Fundamental development– a quest for PIXE based speciation
Elemental Characterization and Speciation
1.5 1.8 2.1 2.40.50
0.75
1.00
1.25
1.50
1.5 1.8 2.1 2.40.60.81.01.21.4
L1-M
2 9.525 keV
L4
no Al-foil
L4
av. with Al-foil
L4
teo
Linear Fit
Lin
e rat
io
W
H+ - Energy (MeV)
1.5 1.8 2.1 2.40.5
1.0
1.5
2.0
2.5
1.5 1.8 2.1 2.40.60.81.01.21.4
Lin
e rat
io (%
)
L1-N5 11.856 keV
L11
no Al-foil
L11
av. with Al foil
Linear Fit
W
H+ - Energy (MeV)
Satellite data for the 29th of February 2000. Courtesy of SeaWiFS Project NASA/GSFC and ORBIMAGE
E. Alves, NuPECC Meeting (Lisbon 2004)
Art and Archaeometry
SiO2
Na+
K+
Ca2+
H+
H2
O
H3
O+
0 1 2 3 45,5
6,0
6,5
7,0
7,5
8,0
8,5
9,0
tempo
pH
Linear!
ERD
H incorporation ion exchangeCa
Ca
Si
-PIXE
Elemental distribution structural change, ion exchange
Ex.: corrosion in medieval K-rich stained-glass compositions
Techniques, provenance, authenticity…Strategies for conservation and restauration (remediation, recovery)…
Mechanisms…
Decomposition by water …
Dissolution of glass network …
Reactions with CO2 , SO2, …
E. Alves, NuPECC Meeting (Lisbon 2004)
Mineralogy and Geosciences
Max.Min.100 µm
SbS Cu Ag
µPIXE elemental distribution
Ilm
A-Sp
Ilm
A-Sp
Ilm
A-Sp
A
VTiFe
PhotoTrace element distribution – Vanadium
Elemental Zonation - Ag
E. Alves, NuPECC Meeting (Lisbon 2004)
- Charge collection efficiency map- Crystallite size and crystallite boundary role
IBIC - Ion Beam Induced Charge
IBIL - Ion Beam Induced Luminescence
- Charged beam creates electron-hole pairs- The sample is also the detector
- radiative recombination of charge carriers- use of a photomultiplier (panchromatic mode)
Charge collection efficiency in polycrystalline diamond detectors
Detector - SEM image
M a x .
M in .
SEM IBIC
Co-planar electrode structure
IBIL
IBIC
- There are no grains with both high IBIC and IBIL signals- “dead” zones are observed - non radiative recombination
E. Alves, NuPECC Meeting (Lisbon 2004)
Support Activities
• Software development for IBA analyses (N.P. Barradas, NIM B217(2004)479)- Double scattering- Roughness, voids, inclusions- Sharp resonance convolution- Efficient Bayesian inference
Non-Rutherford Cross-Section
Measurements (A.R. Ramos, NIM B190(2002)95)
Technical Developments: Furnaces, Electronics....
500 1000 1500 2000 25000
10
20
30
40
50
60
70
Rat
io T
o R
uthe
rfor
d
Energy (keV)
Measured x-section for =178º Calculated (Gurbich, NIM B136-138 (1998))
E. Alves, NuPECC Meeting (Lisbon 2004)
Si(100)/Al2O3 500nm/(CoFeB 2 nm/Al2O3 0.9 nm)×4/Ta 2nm
Output: (2003/2004)
Publications
JournalsPublished:
59Submitted:
48
Collaborations
Projects
NationalAccepted: 13Submitted: 10
InternationalAccepted: 7Submitted: 1
National: 18
International: 11
Invited: 4
Oral: 11 Posters: 39
ThesesPhD: 2MSc: 2Lic.:3
Conferences and Workshops
E. Alves, NuPECC Meeting (Lisbon 2004)
That’s all
thanks for your attention
E. Alves, NuPECC Meeting (Lisbon 2004)
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