Electrospun nanofibrous materials as X-ray sources at atmospheric conditions Pavel Pokorný, Petr...

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


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


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


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


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


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


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


4/3

32

Experimental


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


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.


Conclusion


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


33

LilyLily

Nanofibres


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


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


Technology

Theron, Yarin, Zussman (2005) Polymer, 46

Needle arrays

Scaling up the technology

1 g/hour1 g/hour


Yarin, Zussman (2004) Polymer, 34

Needleless Needleless ElectrospinningElectrospinning

Technology


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


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,


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


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


Experimental

Cleft spinner

,....E


Rayleigh instabilityRayleigh instability

087.2 r

12

02

000

013

0

2 rkrkrkI

rkI

r

rr0

Physics


32 kV

Experimental


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


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


X- ray attenuation


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

Electrospun nanofibrous materials as X-ray sources at atmospheric conditions Pavel Pokorný, Petr...

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