Balloelectric genesisof intermediate

ions(a synopsis)

Hannes Tammet,Urmas Hõrrak, Kaupo Komsaare, Markku Kulmala

CHRONOLOGY

1744: Richmann – air conductivity

1785: Coulomb – rediscovery of air conductivity

1834: Faraday – term ion

1840: Faraday – explanation of Seghill incident

1892: Lenard – studies of balloelectric effect1896: Thomson & Rutherford – mobility

1899: Elster & Geitel – atmospheric small ions

1905: Langevin – large ions

1913: Christiansen – term balloelectric effect

1915: Pollock – intermediate ions

1937: Chapman – mobility of balloelectric ions

1973: Siksna – water clathrates

1999: Chaplin – water superclusters

Annalen der Physik 1892

Lenard, P. (1915) Über Wasserfallelektrizität und über die Oberflächenbeschaffenheit der Flüssigkeiten. Annalen der Physik 47, 463–524.

Philipp Eduard Antonvon Lénárd,

a Magyar from Bratislava,Nobel Prize 1905

Previous work by the authors

of the presentation

Experimental study of the “rain effect” on the mobility distribution of air ions.

Experiments with water jet.

U. Hõrrak, H. Tammet, E.Tamm, A. Mirme.

Institute of Environmental Physics, University of Tartu,

18 Ülikooli St., 50090 Tartu, Estonia.

E-mail: Urmas.Horrak@ut.ee

Pikajärve, June 27–29. 2005

Hõrrak, U., Tammet, H., Aalto, P.P., Vana, M., Hirsikko, A., Laakso, L., Kulmala, M. (2006) Formation of Charged Nanometer Aerosol Particles Associated with Rainfall: Atmospheric Measurements and Lab Experiment. In Report Series in Aerosol Science, Helsinki, 81, 180-185.

?

Size of the Size of the balloelectric ionsballoelectric ionsH. Tammet, U. Hõrrak, M. Kulmala

Pühajärve 2008

2009

Raintime bursts of intermediate

ions

Tartu, Tähe 4 attic storey and roof

0369

12

0 3 6 9 12 15 18 21 24

Tem

pera

ture

N

ois

e

85

90

95

100

RH

%

Precipitation

A rainy day in Tartu, April 2004

A rainy day in Hyytiälä, 6 December 2006.Air temperature +5.0…+8.5 ºC and RH 83…96% during the day.

0

250

500

750

1000

1250

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9Mobility, cm2V-1s-1

dn /

d(lo

g d)

, cm

-3>= 3 mm/h

2.0–2.9 mm/h

1.0–1.9 mm/h

0.1–0.9 mm/h

Average mobility distribution of negative atmospheric ions during the rain of different intensity in Hyytiälä.

Diameter = f (charge, mobility)

THE PROBLEM:

singly or multiply charged particles?

We can measure the mobility.How to estimate the size?

0

0.25

0.5

0.75

1

1 10 100 1000 10000

Droplet diameter, nm

Ele

ctric

mob

ility

, cm

2 V-1

s-1Rayleigh limit charge

Half of theRayleigh limit

Single charge

Mobility of a typical balloelectric ion

Singly charged particles: The concentration decreases, but the mobility does not change.

Multiply charged particles: The number concentration does not change, the mobility and the charge concentration decrease proportionally to each other.

Idea of the neutralization experiment:

0

50

100

150

200

250

300

350

400

450

500

550

600

0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45 0.5 0.55 0.6 0.65Mobility, cm2V-1s-1

Fra

ctio

n co

ncen

trat

ion

cm-3

REPEATED MEASUREMENTSAT FOUR LEVELSOF NEUTRALIZATION

0

500

1000

1500

2000

2500

3000

3500

4000

4500

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9Mobility, cm2V-1s-1

Dis

trib

utio

n of

cha

rge

conc

entr

atio

n

n+ = 810

n+ = 3320

n+ = 5770

n+ = 9700

Old particles are neutralized and do not affect this curve

Large mobility → small size

Old particles are waned due to the

evaporation

Small ions

dn /d (log Z)cm-3

Results of experiments: mobility decreases a little, far from the proportionality

Concentration of neutralizing small ions, cm-3

Conclusion:

The balloelectric ions are mostly the singly charged nanometer particles and

diameter = f (1 e, mobility)

Composition: water

or dry residueof a droplet?

The rainwater contains about 10 mg/l ofTDS (total dissolved solids).

The waterworks water used in the experiments contains 550 mg/l of TDS.

Conclusion: the dry residues of the waterworks water droplets should have 3-4 times bigger diameters when compared with the dry residues of the rainwater droplets.

Let’s compare…

Comparison of measurements at Hyytiälä SMEAR station (left)

and results of the experiment with water jet (right)

Size distributions of negative ions

0 .4 0 .6 0 .8 1 1 .2 1 .6 2 3 4 5 6 7 8

Mass d iam eter (n m )

Neg ative ion s. Au g u st 23, 2003.

0

100

200

300

400

500

600

Fraction concentration (cm

-3)

16 :17 16 :22 16 :27 16 :32 16 :38 16 :43 16 :48

0 .4 0 .6 0 .8 1 1 .2 1 .6 2 3 4 5 6 7 8

Mass d iam eter (n m )

Neg ative ion s. May 12, 2005.

0

100

200

300

400

500

600

Fraction concentration (cm

-3)

12 :45 12 :55 13 :05 13 :15 wa te r 13 :25 wa te r 13 :35 wa te r 13 :45 13 :55 14 :05

Rain event. Hyytiälä Laboratory water-jet. Tartu

0

500

1000

1500

2000

2500

3000

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9Mobility, cm2V-1s-1

dn /

d(lo

g d)

, cm

-3

Blue – natural rain at Hyytiälä, green – natural rain at Tartu, red – laboratory experiment splashing the waterworks water

Conclusion:

The size of balloelectric ions does not depend on the TDS and they cannot be considered as dry residues of droplets.

How the balloelectric

ions are created ?

Critical point: the surface tension requires a lot of energy to be saved in the surface of nanodroplets, where is the source?

The speed of large raindrops is 6-7 m/s. If 100% of the kinetic energy is to be transformed into the surface energy then the required speed is:

Dispersion of a raindrop fully into nanodrops seems to be impossible. However, the law of energy balance cannot exlude creating of a limited number of nanodrops. The nanometer scale processes during the splashing are hard to study and the mechanism of creating the nanodrops is almost unknown.

d : nm 10 100 1000 10000

v : m/s 290 90 29 9

Nobel prize winner 2002 John B. Fenn studied generating of ions of dissolved substances.

(ESI = electrospray ionization)

Wide field of ESI applications motivated research of Coulomb dispersion of droplets. Indeed, the fragments can be very small. However, they are

MULTIPLY CHARGED

Why they are not instantly evaporated ?

The characteristic evaporation time of 2.5 nm liquid water droplets at 10ºC and 100% relative humidity does not exceed 1 μs according to the kinetic theory. This time is about 7 magnitudes less than the estimated time of passage of the air to the instrument and 5 magnitudes less than the time of passage of the air through the analyzer.

If these estimates were true then the observation of 2.5 nm droplets in the described measurements would be recognized as impossible.

WATER JET OPEN WATER JET CLOSED

fine + coarse +

coarse –

fine –

Conclusion:

The balloelectric ions are not composed of the liquid water. ICE CRYSTALS ?

CLUSTERS ?

Lenard 1915

n = 21d = 1.06Z = 0.96

SIZE OF A BALLOELECTRIC ION CORRESPONDS TO

200…300MOLECULES OF WATER

Chaplin’s superclusters?

Number of water molecules

n = (πρd3 / 6) / (18 u)

n 17.5 (d / 1 nm)3 n = 280 follows d = 2.52 nm.

The water clusters known in mass spectrometry have maximum n = 21. Chaplin did not use mass spectrometry and does not refer experts like Beyer, Kebarle, Keesee and Castleman.He studied clusters not in the gas but in the water environment.

Chaplin’s magic icosahedron has n = 20×14 = 280

LINKS

• http://www.lsbu.ac.uk/water

• http://www.waterjournal.org

• http://www.mdpi.com/journal/water

• http://water.sigmaxi.org/?page_id=39

the last site contains a list of more than 60

journals related to water and hydrology

Picturesfrom Chaplin’s web:

Stable supercluster

A superlcuster can break down during long time

0

500

1000

1500

2000

2500

3000

1 10 100 1000 10000Number of water molecules

Mob

ility

fra

ctio

n co

ncen

trat

ions

cm

-3

A+

B+

C+

D+

A-

B-

C-

D-

Distribution of balloelectric ions according to the number of water moleculesA, B, C ja D are levels of neutralizing ionization in the laboratory experiment

Final conclusions:Nature of rain-induced intermediate ions seems to be the same as nature of balloelectric ions in laboratory and near waterfalls. We proved that the balloelectric ions are probably

1) singly charged nanoparticles,2) not dry residues of droplets,3) not composed of classic liquid water,4) of size the Chaplin's 280-superclusters.

We still don't know1) their actual composition,2) how they are created,3) why they are not instantly evaporated.

Thank you for attention !

? ? ? ? ? ? ?CONCLUSION CONCLUSION