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Electrospun nanofibrous materialsas X-ray sources at atmospheric
conditions
Pavel Pokorný, Petr Mikeš
and David Lukáš1Electrospinning - X-rays
2
Technical University of LiberecTechnical University of LiberecCzech RepublicCzech Republic
Clemson University Electrospinning - X-rays 3
William Gilbert1600amber
HistoryHistory
Clemson University Electrospinning - X-rays 4
Solvent Solvent evaporationevaporation
WhippingWhipping
Taylor coneTaylor cone
Stable jetStable jet
d =200 nmd =200 nm
1111
22
Polymer Polymer solutionsolution
Self-organized nanofibrous layer
Self-organizationSelf-organization John ZelenyJohn Zeleny (1872-1951) (1872-1951) Czech-American physicistCzech-American physicist
5
Epoxy resin
EE
no.no.
11 22 33 44
66
Self-organization
1 2 3 4 5 61 2 3 4 5 6
E = 0E = 0
E = EE = Ecc
EEcc
A rode instead of a A rode instead of a needleneedle
55
d=1cm
+++
++ ++++
++++++++++++ ++ ++
Stationary wave
F.Sanetrník
Sandra Torres
Clemson University Electrospinning - X-rays 6
Technology
Jirsák, O. Sanetrník, F. Lukáš, D. Kotek, V. Marinová, L. Chaloupek, J. (2005) WO2005024101 A Method of Nanofibres Production from A Polymer Solution Using Electrostatic Spinning and A Device for Carrying out The Method.
www.elmarco.comwww.elmarco.com
Clemson University Electrospinning - X-rays 7
Capillary force
Elektrostatic force
cos2 rFc
)09.0(30.12
ln42 rr
hVc
ce FF Force equilibrium !
r
eF
cF
h
Physics
Sir G. Taylor (1964) Disintegration of water drops in an electric field, Proc. Roy. Soc. A, vol. 280, 1964, pp. 383-397
Needle ElectrospinningNeedle Electrospinning
dsEFe22/1
permitivitypermitivity
Clemson University Electrospinning - X-rays 8
Wave vector
Angular frequency
Physics Needleless electrospinning
Dynamic phenomenon: field strength increment can lead to unlimited growth of a wave amplitude.
A. SarkarA. Sarkar
tkxiAtx exp,
Growth factor
Amplitude
Clemson University Electrospinning - X-rays 9
ikxAetx t exp, Im
cEE Stable amplitudeStable amplitude
GrowingGrowing amplitude amplitudecEE
Physics
tkxiAtx exp, 02
02 Lukas D Sarkar A Pokorny P, SELF ORGANIZATION OF JETS IN ELECTROSPINNING FROM FREE LIQUID SURFACE - A GENERALIZED APPROACH, ACCEPTED FOR PUBLICATION, Journal of Applied Physics, 103 (2008), 309-316.
?,2 kfDispersion lawDispersion law
Clemson University Electrospinning - X-rays 10
kkEkg 222
Stable waves of various wave numbers and angular frequencies.
Fastest forming instability
The only wave
02
02
Physics
Various field Various field strengthsstrengths
tAe Im
cEE
cEE
E
E
Tonks-Frenkel instabilityTonks-Frenkel instability
Clemson University Electrospinning - X-rays 11
4/3
32
Experimental
Clemson University Electrospinning - X-rays 12
Linear clefts emit polymeric jets. Linear clefts in (a) and (b) emit polymeric (polyvinyl alcohol) jets at the voltages, 32 kV and 43 kV, respectively. The inter-jet distance / wavelength is . The distance between the cleft and the collector was adjusted on 802 mm.
b
ba EE 32 kV 43 kV
Experimental
13Clemson University Electrospinning - X-rays
Electrospun nanofibrous materials as X-ray sources
++ ++
10 /E MV mClemson University 14
St. Elmo‘s fire
ce pp R
E 2
2
10
D.H. Reneker, A.L. Yarin / Polymer 49 (2008) 2387-2425.15
Taylor coun
cml 10kVV 30
First observation of
radiation recorded in
X-ray sensitive film.
16
Shield: -black paper, 160 g/m-2 -Aluminum foil, 0.01 mm, 25 gm -2.
Deutherium lamp HERAEUS D200F, 300W, UV light ,160 nm- 400 nm, i.e. 120 eV - 50 eV,
Clemson University Electrospinning - X-rays
P. Pokorný observation
Electrospinning setupSetup with parallel and fixed gold- coated nanofibers
X-ray recordX-ray record SEM microphotographSEM microphotographClemson University
Experimental setup
The detected radiation arose from the vicinity of freshly electrospun nanofibres as The detected radiation arose from the vicinity of freshly electrospun nanofibres as proven by the geometrical similarity of the tracks recorded on a radiographic film proven by the geometrical similarity of the tracks recorded on a radiographic film and the location of deposited nanofibrous heapsand the location of deposited nanofibrous heaps..
18
X-ray records
19Clemson University
X-ray records
Kirlian photography
--Premium performance Premium performance sspectroscopy from 1 keV to 30 keVpectroscopy from 1 keV to 30 keV-E-Energy resolution 35 eVnergy resolution 35 eV--Thin Be windowThin Be window, , 25 25 mm-Nitrogen cooled-Nitrogen cooled
Prof. Tomáš Čechák Prof. Tomáš Čechák FJFI, ČVUT – Prague FJFI, ČVUT – Prague
20Clemson University Electrospinning - X-rays
SLP Silicon Lithium-Drifted Low-Energy X-Ray Detector
1
10
100
1000
10000
100000
1 3 5 7 9 11 13 15 17 19 21
Energy [keV]
phot
on c
ount
s
1
10
100
1000
10000
100000
1 3 5 7 9 11 13 15 17 19 21
Energy [keV]
phot
on c
ount
s
1
10
100
1 3 5 7 9 11 13 15 17 19 21
Energy [keV]
phot
on c
ount
s
1
10
100
1000
10000
1 3 5 7 9 11 13 15 17 19 21
Energy [keV]
phot
on c
ount
s
21
Electromagnetic spectrum of radiation
22
Continuious ‘bremsstrahlung’ and Discrete ‘characteristic radiation’
SpectraSpectra
23
Continuious ‘bremsstrahlung’ and Discrete ‘characteristic radiation’
?/300? mGVE keVlEW 30
nml 100
24
Richard P. Feynman: „There‘s plenty of room at the bottom.“ (1959) Richard P. Feynman: „There‘s plenty of room at the bottom.“ (1959)
teratera TT 10101212
gigagiga GG 101099
megamega MM 101066
kilokilo kk 101033
prefixprefix
X-ray sources at atmospheric conditions
25
2ln0
1 E
E
ah /
MACROMACRO
NANONANOClemson University Electrospinning - X-rays
Macro and nano …
NANO
h = 10 cm a = 50 nm
mGVE /391
keVlEW 9.31
20
E
EW mGVEW /095.0keVlEW W 095.0
26
ad /Clemson University Electrospinning - X-rays
Warp of fibers
mmd 1.0
8 x 108 x 1088
mm-3-3
Clemson University 27Electrospinning - X-rays
Ionic clouds, Debye length, Manning region, Counterion condensation
Tk
rer
rr
B
c
exp
Poisson–Boltzmann equationPoisson–Boltzmann equation
0 5 10 15
5
10
15
20
x
x
--
++
Mi R
rzru lnln2
56.0
407.16
z
RM
Kornev K. Kornev K. Lateral interactions of charges in thin liquid films Lateral interactions of charges in thin liquid films and the Berezinskii-Kosterlitz-T houless transitiv, and the Berezinskii-Kosterlitz-T houless transitiv, Physical Physical Review EReview E, , 6060 (4), 8554-8559 (1999). (4), 8554-8559 (1999).
mGVE /3651
keVlEW 5.361 28
mGVE /3651
Manning region
29
Needleless electrospinning is promising industrial Needleless electrospinning is promising industrial technology.technology.
It will be worthwhile to investigate x-ray emission It will be worthwhile to investigate x-ray emission from nanofibrous electrodes in a more intensive from nanofibrous electrodes in a more intensive manner, since it could find applications in a lot of manner, since it could find applications in a lot of fields. fields.
Clemson University Electrospinning - X-rays
Conclusion
Clemson University Electrospinning - X-rays 30
AntonAntoníín Kopaln Kopal
Konstantin KornevKonstantin Kornev
Acknowledgement
Thank you for your attention.
You are more than welcome to an open discussion.
31
Radon daughter deposition on electrostatically charged surfacesRadon daughter deposition on electrostatically charged surfaces
Background levelBackground level
Measurement by Geiger – Muller detectrorMeasurement by Geiger – Muller detectror
Radiant energy ranges of Gamma-radiation: Radiant energy ranges of Gamma-radiation: from 0,06 to 1,2 MeVfrom 0,06 to 1,2 MeVRadiant energy ranges of Beta-radiation: Radiant energy ranges of Beta-radiation: from 0,5 from 0,5 to 3 to 3 MeVMeV
32Clemson University Electrospinning - X-rays
33
LilyLily
Nanofibres
Clemson University Electrospinning - X-rays 34
W.J. Morton: Method of dispersing fluids, US Patent, Seriál No. 705,691, July 29, 1902 (Application 1900)
„Electrical method where volatile fluids are separated from their combination or association with relatively non-volatile or fixed substances in composite fluids.“
HistoryHistory Needleless ElectrospinningNeedleless Electrospinning
Clemson University Electrospinning - X-rays 35
John ZelenyJohn Zeleny (1872-1951) was a (1872-1951) was a Czech-American Czech-American physicist at the physicist at the University of University of Minnesota. Minnesota. His work is seen by His work is seen by some as a some as a beginning to beginning to emergent emergent technologies like technologies like liquid metal ion liquid metal ion sources and sources and electrospraying and electrospraying and electrospinning.electrospinning.
HistoryHistory Needle Needle ElectrospinningElectrospinning
Clemson University Electrospinning - X-rays 36
Technology
Theron, Yarin, Zussman (2005) Polymer, 46
Needle arrays
Scaling up the technology
1 g/hour1 g/hour
Clemson University Electrospinning - X-rays 37
Yarin, Zussman (2004) Polymer, 34
Needleless Needleless ElectrospinningElectrospinning
Technology
Clemson University Electrospinning - X-rays 38
Needleless ElectrospinningNeedleless Electrospinning
Bubble ElectrospinningBubble ElectrospinningYong Liu, Yong Liu, Ji-Huan HJi-Huan Hee
International Journal of Nonlinear Sciences and Numerical SimulationInternational Journal of Nonlinear Sciences and Numerical Simulation, 8(3),, 8(3),20072007
Clemson University Electrospinning - X-rays 39
tkxiAtx exp, te Im
cEE
t
tii
)Im(exp
)Im(exp
Stable amplitudeStable amplitude
GrowingGrowing amplitude amplitude Growing parameterGrowing parameter
cEE is imaginary 02
Physics
tkxiAtx exp,
Clemson University Electrospinning - X-rays 40
dt
vdp
Euler equation
0202
2
0
kE
xg
t z
Landau equation
gravitationSurface tension
Elektrostatic forces
Physics
?2 f
kkEkg 2
022 dispersion law
Velocity potential
/2k
Clemson University Electrospinning - X-rays 41
Critical field strength for needle electrospinner.
Experimental
gEE
1222
1222
020
2r
J. Zeleny, Phys. J. Zeleny, Phys. Rev. 3 (1914), Rev. 3 (1914), p. 69p. 69
Clemson University Electrospinning - X-rays 42
Experimental
Cleft spinner
,....E
Clemson University Electrospinning - X-rays 43
Rayleigh instabilityRayleigh instability
087.2 r
12
02
000
013
0
2 rkrkrkI
rkI
r
rr0
Physics
Clemson University Electrospinning - X-rays 44
32 kV
Experimental
Clemson University Electrospinning - X-rays 45
42 kV
'Physical principles of electrospinning (Electrospinning as a nano-scale technology of the twentyfirst century)',Textile Progress,41:2, 59 -140, (2009).
Experimental
1 cm
46
PolystyrenePolystyrene
DensityDensity =1.060E+00 (g/cm=1.060E+00 (g/cm33)) EnergyEnergy tt1/21/2
((kkeV) eV) (cm(cm22/g) /g) (mm)(mm) 1.00000E-03 1.00000E-03 2.040E+03 2.040E+03 0,004260,004265.00000E-03 5.00000E-03 1.767E+01 1.767E+01 0,5330,5331.00000E-02 1.00000E-02 2.219E+00 2.219E+00 4,5214,5212.00000E-02 2.00000E-02 4.363E-01 4.363E-01 21,62221,622
Clemson University Electrospinning - X-rays
47
http://physics.nist.gov/PhysRefData/XrayMassCoef/cover.htmlhttp://physics.nist.gov/PhysRefData/XrayMassCoef/cover.htmlAir, Dry (Near Sea Level)Air, Dry (Near Sea Level)
DensityDensity= = 1.205E-031.205E-03 (g/cm(g/cm33))
EnergyEnergy tt1/e1/e
((kkeV) eV) (cm(cm22/g) /g) (mm)(mm) 1 1 3.606E+03 3.606E+03 2,3012,301 5 5 4.027E+01 4.027E+01 24,22624,2261100 5.120E+00 5.120E+00 162,085162,085 2200 7.779E-01 7.779E-01 1068,0511068,051
The mass attenuation coefficient, The mass attenuation coefficient,
/
/
t
I
I
exp0
1/1 et
Clemson University Electrospinning - X-rays
X- ray attenuation
Clemson University Electrospinning - X-rays 48
Kirlian photography: If an object on a photographic plate is connected to a source of high voltage, small corona discharges (created by the strong electric field at the edges of the object) create an image on the photographic plate.
Kirlian Photography
10
1
2lnZ
E
E
1Z
ah /
h = 10-1 m a = m
51 103.1 Z
mGVE /391
keVlEW 9.31
49
Single fiber
50
The X-ray radiation
mkVE /300
keVlEW 30
cml 10
51
kVV 30
Clemson University
Crookes tubes: invented by British Crookes tubes: invented by British physicist William Crookes and othersphysicist William Crookes and others inin1920s.1920s.
X- ray tube