The Study of Fast Processes and Transient Species by Electron Pulse Radiolysis: Proceedings of the NATO Advanced Study Institute held at Capri, Italy, 7–18 September, 1981

638 Pages·1982·32.671 MB·English

by  Gordon R. Freeman (auth.), John H. Baxendale, Fabio Busi (eds.)

The Study of Fast Processes and Transient Species by Electron Pulse Radiolysis
NA TO ADVANCED STUDY INSTITUTES SERIES
Proceedings of the Advanced Study Institute Programme, which aims
at the dissemination ofa dvanced knowledge and
the formation of contacts among scientists from different countries
The series is published by an international board of publishers in conjunction
with NATO Scientific Affairs Division
A Life Sciences Plenum Publishing Corporation
B Physics London and New York
C Mathematical D. Reidel Publishing Company
and Physical Dordrecht, Boston and London
Sciences
D Behavioural and
Social Sciences Martinus Nijhoff Publishers
E Engineering and The Hague, London and Boston
Materials Sciences
F Computer and Springer Vedag
Systems Sciences Heidelberg
G Ecological Sciences
Series C - Mathematical and Physical Sciences
Volume 86 - The Study of Fast Processes and Transient Species
by Electron Pulse Radiolysis
The Study of Fast Processes
and Transient Species
by Electron Pulse Radiolysis
Proceedings oft he NATO Advanced Study Institute
held at Capri, Italy, 7-18 September, 1981
edited by
JOHN H. BAXENDALE
Chemistry Department, The University, Manchester, U.K.
and
FABIO BUSI
Instituto F.RA.E., C.N.R., Bologna, Italy
D. Reidel Publishing Company
Dordrecht: Holland! Boston: U.S.A.! London: England
Published in cooperation with NATO Scientific Affairs Division
library of Congress Cataloging in Publication Data
NATO Advanced Study Institute (1981 : Capri, Italy)
The study of fast processes and transient species by electron pulse
radiolysis.
(NATO advanced study institutes series. Series C, Mathematical
and physical sciences; v. 86)
Includes bibliographical references and index.
"Published in cooperation with NATO Scientific Affairs Division."
1. Radiation chemistry-Congresses. I. Baxendale, John H.,
1917- II. Busi, Fabio. III. Title. IV. Series.
QD625.N37 1980 541.3'8 82-9067
AACR2
[SBN-13: 978-94-009-7854-6 e-[SBN-13: 978-94-009-7852-2
00[: 10.1007/978-94-009-7852-2
Published by D. Reidel Publishing Company
P.O. Box 17,3300 AA Dordrecht, Holland
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by Kluwer Boston Inc.,
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In all other countries, sold and distributed
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D. Reidel Publishing Company is a member of the Kluwer Group
All Rights Reserved
Copyright ([:) 1982 by D. Reidel Publishing Company, Dordrecht, Holland
Softcover reprint of the hardcover 1s t edition 1982
No part of the material protected by this copyright notice may be reproduced or utilized
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without written permission from the copyright owner
CONTENTS
Preface xv
ABSORPTION OF ENERGY FROM IONIZING RADIATION
Gordon R. Freeman
1. X-rays and y-rays. 5
(a) Photoelectric effect 7
(b) Compton effect 8
(c) Pair production 10
2. Electrons. 11
(a) Excitation and ionisation of molecules 12
(b) Emission of radiation 12
(c) Electron range 13
(d) Low energy electrons 13
3. Heavy positive Particles. 15
(a) High energy 15
(b) Low energy 15
4. Neutrons. 16
References. 17
BASICS OF RADIATION CHEMISTRY
Gordon R. Freeman 19
Spacial Distribution and Reaction Kinetics. 20
1. Charge Particle Tracks and Track Densities. 20
2. Spur Reactions. 22
3. Non-Homogeneous Kinetics. 23
Time Scale of Events in a Liquid. 24
1. Development. 24
2. Summary of Time Scale. 32
References. 33
SOURCES OF PULSED RADIATION
Myran C. Sauer Jr. 35
1. Introduction. 35
2. Types of Pulsed Radiation Sources. 36
2.1. Microwave linear accelerators 37
2.2. Febetrons 39
2.3. Other sources of pulsed radiation 41
3. Physical Dosimetry for Pulses Sources. 43
References. 46
CONTENTS
~
CHEMICAL DOSIMETRY OF PULSED ELECTRON AND X-RAY SOURCES
IN THE 1-20 MeV RANGE
E. Martin Fielden 49
1.1. Units of Absorbed Dose 49
1.2. Units of Radiation Chemical Yield 49
2.1. Principles of Chemical Dosimetry 50
2.2. The Ferrous Sulphate or Fricke Dosimeter 50
2.3. The "Super Fricke Dosimeter" 52
2.4. Other Dosimeters Suitable for High
Intensity Pulsed Sources 52
3.1. Dosimetry by the Measurement of Fugitive
Species 53
3.2. Sources of Error 55
1. Correction due to pulse duration 55
2. Correction for response time of
system 57
3.3. The Thiocyanate Dosimeter 58
3.4. The Hydrated Electron Dosimeter 59
3.5. The Ferrocyanide Dosimeter 60
References 61
OPTICAL MONITORING TECHNIQUES
G. Roffi 63
1. General Considerations 63
2. Optical Systems 66
2.1. Lenses 67
2.2. Mirrors 70
2.3. Light-~ources 71
2.4. Monochromators 74
3. Monitoring Techniques 78
3.1. Photodetectors 78
3.2. Photomultipliers 78
3.3. Photodiodes 82
3.4. Detector circuits 84
References 89
CONDUCTIVITY MONITORING TECHNIQUES
K.-D. Asmus and E. Janata 91
Electrical Principles 92
Limi tations 95
Experimental Set-ups 98
Chemical Examples 102
Conclusion III
References 113
CONTENTS vii
POLAROGRAPHY MONITORING TECHNIQUES
K.-D. Asmus and E. Janata lIS
Experimental Section 116
Examples 118
Conclusion 127
References 127
THE MICROWAVE ABSORPTION TECHNIQUE FOR STUDYING IONS
AND IONIC PROCESSES
John M. Warman 129
Introduction 130
Expe rimen tal 134
General 134
Circuit components 135
Irradiation cells 139
Irradiation conditions 140
Data Reduction 141
Reflection cell 142
Resonant cavity cell 147
The yield-mobility product 150
Application and Comparison with other Techniques 151
References 158
EPR AND NMR DETECTION OF TRANSIENT RADICALS AND
REACTION PRODUCTS
Alexander D. Trifunac 163
Introduction 163
Time Resolved EPR 167
Pulsed EPR 167
Time resolved spectra 169
Time sweep 170
Free induction decay 171
NMR in Radiation Chemistry 173
References 177
RADICAL IONS AND EXCITED STATES IN RADIOLYSIS.
OPTICALLY DETECTED TIME RESOLVED EPR
Alexander D. Trifunac and Joseph P. Smith 179
Introduction 179
Method, Results and Discussion 180
References 187
viii CONTENTS
LIGHT SCATTERING TECHNIQUES FOR INVESTIGATION OF
TRANSIENTS PRODUCED IN ELECTRON PULSE RADIOLYSIS
M. A. J. RODGERS 189
Rayleigh Scattering 189
Raman Scat tering 190
Background 190
Origin of resonance enhancement 191
Experimental 193
Pulse radiolysis and TR3 detection 193
Current activity 195
References 197
DATA ACQUISITION AND ANALYSIS IN PULSE RADIOLYSIS
PART I: CONTROL, DIGITIZATION, AND ANALYSIS
David C. Foyt 199
1.0. Introduction 199
2.0. Timing and Control 200
3.0. Digitisation of the Transient Signal 202
3.1. Oscilloscopes 202
3.2. Electronic digitiser 203
3.3. Diode matrix technique 204
3.4. Streak cameras 204
3.5. Pulse-probe technique 205
3.6. Counting methods 205
3.7. Computer as digitiser 206
4.0. Data Processing and Analysis 206
4.1. Initial data processing 206
4.2. Simple linear fitting 207
4.3. Iterative linear regression 208
4.4. Direct solution of kinetic equations 209
4.5. Deconvolution 209
4.6. Statistical considerations 210
5.0. Conclusion 211
References 211
DATA ACQUISITION AND ANALYSIS IN PULSE RADIOLYSIS
PART II: COMPUTERIZATION
David C. Foyt 213
1.0. Introduction 213
2.0. Historical Survey 215
2.1. The computer revolution 215
2.2. Computers in pulse radiolysis 216
CONTENTS ix
3.0. Techniques of Laboratory Computerisation 2'7
3.1. Computer hardware 217
Minicomputers 218
Microcomputers 218
3.2. Hardware Interfacing 218
Camac 219
GPIB 219
S-l00 Bus 219
Ethernet 220
3.3. Operating systems 220
3.4. Programming languages 221
4.0. Some General Aspects of Design and
Implementation 222
4.1. Flexibility 222
4.2. Ease of use 223
4.3. Manual control option 223
4.4. How much ~omputerisation? 224
5.0. Conclusion
References 225
RAPID TECHNIQUES FOR CORRECTING NANOSECOND KINETIC
TRACES FOR CONVOLUTION ERROR
David C. Foyt 227
1.0. Introduction 227
2.0. Separation of the Convolution Integral 228
3.0. Model Excitation Response Function 230
4.0. Discussion 232
5.0. Examples 235
6.0. Conclusion 239
References 240
BASIC RADIATION CHEMISTRY OF LIQUID WATER
G. V. Buxton 241
1. Introduction 241
2. Primary Events 242
3. Experimental Evidence for Spurs 244
4. Yields of the Primary Species 248
4.1. Yields in neutral solution 248
4.2. Dependence on pH 250
5. Initial Yields 252
6. Properties of the Primary Radicals 255
6.1. Hydrated electron 255
6.2. Hydrogen atom 258
6.3. Hydroxyl radical 259
6.4. Perhydroxyl radical 261
x CONTENTS
7. Water Radiolysis as a Chemical Tool 261
7.1. Oxidising conditions 262
7.2. Reducing conditions 262
8. Concluding Remarks 263
References 264
APPLICATIONS OF WATER RADIOLYSIS IN INORGANIC CHEMISTRY
G. V. Buxton 267
1. Introduction 267
2. Inorganic Free Radicals 268
3. Non-metallic Compounds 270
3.1. Oxyhalogen ions 270
3.2. Borohydride ion 271
4. Aquo-metal Ions in Unusual Oxidation States 273
5. Lanthanides and Actinides 275
6. Transition Metal Complexes 279
6.1. Electron transfer 279
6.2. Coordinated free radicals 280
6.3. Aquation of transition metal complexes 282
6.4. Change in symmetry 283
7. Concluding Remarks 284
References 285
APPLICATION OF PULSE RADIOLYSIS TO THE STUDY OF
AQUEOUS ORGANIC SYSTEMS
A. J. Swallow 289
Reactions of OH, e and H 290
aq
Hydroxyl radicals 290
Hydrated electrons 292
Hydrogen atoms 294
Design of Experiments 294
Radicals formed from OH reactions 296
Radicals formed from e- reactions 296
Radicals formed from Ha~eactions 298
Acid-base properties 298
Errors 300
Free Radicals Formed from Organic Compounds 302
Hydrocarbons 302
Halides 304
Alcohol and carbonyl compounds 306
Sulphur compounds 312
References 314