Radiation‐Induced Conductivity in Plastic Films at High Dose Rates

1965 ◽  
Vol 36 (8) ◽  
pp. 2434-2443 ◽  
Author(s):  
D. M. J. Compton ◽  
G. T. Cheney ◽  
R. A. Poll
Keyword(s):  
High Dose ◽  
Plastic Films ◽  
Dose Rates ◽  
Radiation Induced

Erratum: Radiation‐Induced Conductivity in Plastic Films in High Dose Rates

1966 ◽  
Vol 37 (5) ◽  
pp. 2203-2203
Author(s):  
D. M. J. Compton ◽  
G. T. Cheney ◽  
R. A. Poll
Keyword(s):  
High Dose ◽  
Plastic Films ◽  
Dose Rates ◽  
Radiation Induced

Radiological Control of Gold Octahedral and Prism Nanoparticles

2007 ◽  
Vol 1056 ◽  
Author(s):  
Tina M. Nenoff ◽  
Jason C. Jones ◽  
Paula P. Provencio ◽  
Donald T. Berry
Keyword(s):  
Dose Rate ◽  
High Dose Rate ◽  
Pure Gold ◽  
High Dose ◽  
Visible Absorption ◽  
Dose Rates ◽  
Radiation Induced ◽  
Radiological Control ◽  
Uv Visible ◽  
Short Time

ABSTRACTWe report on a fundamental morphology growth of gold-based nanoparticles by solution radiolysis. Radiolysis of pure gold-polymer solutions of different dose rates and aging time is examined. A detailed description will be presented of the experimentation, testing and analysis. In particular, we will present data on the formation of gold nano-octahedra and -prism particles. The γ-irradiations were carried out with a 60Co source of 1.345 × 105 Ci (Sandia National Laboratories Gamma Irradiation Facility (GIF). Nanoparticle characterization techniques included are UV-vis and TEM. Similar to what has been seen in earlier silver nanoparticle studies, dose rate dictates the size of nanoparticles formed. At high dose rate, all reducing species are produced and scavenged within a short time, and then coalesce into separate nanoparticles. At low dose rate, the coalescence process is faster than the production rate of the reducing radicals. The reduction of radicals occurs mainly on clusters already formed. The differences in the morphologies result from a combination of dose rate, aging and lack of radical scavengers (e.g. isopropyl alcohol), resulting in either gold nano-spheres, octahedral or prism nanoparticles. The progressive evolution with dose rate of the UV-visible absorption spectra of radiation-induced metal clusters is discussed.

Studies in radiation-induced polymerization of vinyl monomers at high dose rates. II. Methyl methacrylate

1974 ◽  
Vol 18 (3) ◽  
pp. 709-725 ◽  
Author(s):  
C. C. Allen ◽  
W. Oraby ◽  
T. M. A. Hossain ◽  
E. P. Stahel ◽  
D. R. Squire ◽  
...  
Keyword(s):  
Methyl Methacrylate ◽  
High Dose ◽  
Vinyl Monomers ◽  
Dose Rates ◽  
Radiation Induced

A Positive-Ion Reaction Mechanism for the Radiation Induced Oxidation of Carbon Monoxide in the High Dose Rate Radiolysis of CO–O2 Mixtures

1972 ◽  
Vol 50 (21) ◽  
pp. 3508-3514 ◽  
Author(s):  
C. Willis ◽  
A. W. Boyd ◽  
P. E. Bindner
Keyword(s):  
Dose Rate ◽  
Low Dose ◽  
High Dose Rate ◽  
High Dose ◽  
Total Oxygen ◽  
Dose Rates ◽  
Electron Scavenger ◽  
Radiation Induced ◽  
A Chain ◽  
Positive Ion

Carbon dioxide and ozone yields have been measured in the irradiation of CO–O2 mixtures with single pulses of electrons. The yields of CO2 at 2 × 1027 ev g−1 s−1 are large G(CO2) = 15 ± 1 from 20–60% O2. These decrease by ∼50% at 1028 eV g−1 s−1. Although the results are somewhat irreproducible the addition of c-C4F8, an electron scavenger, increases these CO2 yields at both dose rates by up to a factor of 15. They are reduced to G(CO2) < 2 by the addition of positive ion scavengers. These results are consistent with a chain reaction similar to that proposed for low dose rate studies involving [Formula: see text], [Formula: see text], and [Formula: see text] as chain carriers.The ozone yields are consistent with a total oxygen atom yield of G(O) = 1.4 in pure CO from neutral processes.

Studies in radiation-induced polymerization of vinyl monomers at high dose rates. I. Styrene

1972 ◽  
Vol 16 (3) ◽  
pp. 645-661 ◽  
Author(s):  
D. R. Squire ◽  
J. A. Cleaveland ◽  
T. M. A. Hossain ◽  
W. Oraby ◽  
E. P. Stahel ◽  
...  
Keyword(s):  
High Dose ◽  
Vinyl Monomers ◽  
Dose Rates ◽  
Radiation Induced

Radiation-induced polymerization of styrene at high dose rates

1977 ◽  
Vol 21 (10) ◽  
pp. 2683-2693 ◽  
Author(s):  
J. Takezaki ◽  
T. Okada ◽  
I. Sakurada
Keyword(s):  
High Dose ◽  
Dose Rates ◽  
Radiation Induced

Radiation Induced Impurity Precipitation in Mgo

1985 ◽  
Vol 60 ◽  
Author(s):  
S. Clement ◽  
E. R. Hodgson
Keyword(s):  
Absorption Band ◽  
Optical Absorption ◽  
Dose Rate ◽  
Reduction Process ◽  
High Dose ◽  
Optical Absorption Band ◽  
Enhanced Diffusion ◽  
Dose Rates ◽  
Radiation Enhanced Diffusion ◽  
Radiation Induced

AbstractIn MgO irradiated at high dose rates and high temperatures with 1.8 MeV electrons, a suppression of the Fe3+ optical absorption band at 290 nm is observed. This suppression, a function of both dose rate and temperature, is consistent with a reduction process induced by oxygen displacement damage. Both thermal and radiation enhanced diffusion are involved and lead to the formation of iron containing precipitates. Similar results have been obtained for Ni2+.

Electron Beam Damage of Biomolecules Assessed by Energy Loss Spectroscopy

1978 ◽  
Vol 36 (3) ◽  
pp. 61-69
Author(s):  
M. Isaacson ◽  
M.L. Collins ◽  
M. Listvan
Keyword(s):  
Electron Microscopy ◽  
Radiation Damage ◽  
Structural Integrity ◽  
Analytical Electron Microscopy ◽  
High Dose ◽  
Dose Rates ◽  
Special Cases ◽  
Analytical Electron ◽  
Atom Migration ◽  
Beam Damage

Over the past five years it has become evident that radiation damage provides the fundamental limit to the study of blomolecular structure by electron microscopy. In some special cases structural determinations at very low doses can be achieved through superposition techniques to study periodic (Unwin & Henderson, 1975) and nonperiodic (Saxton & Frank, 1977) specimens. In addition, protection methods such as glucose embedding (Unwin & Henderson, 1975) and maintenance of specimen hydration at low temperatures (Taylor & Glaeser, 1976) have also shown promise. Despite these successes, the basic nature of radiation damage in the electron microscope is far from clear. In general we cannot predict exactly how different structures will behave during electron Irradiation at high dose rates. Moreover, with the rapid rise of analytical electron microscopy over the last few years, nvicroscopists are becoming concerned with questions of compositional as well as structural integrity. It is important to measure changes in elemental composition arising from atom migration in or loss from the specimen as a result of electron bombardment.

Electron-diffraction studies in synthetic polymer materials

1983 ◽  
Vol 41 ◽  
pp. 362-365
Author(s):  
D.T. Grubb
Keyword(s):  
Electron Diffraction ◽  
Synthetic Polymer ◽  
Polymer Materials ◽  
Crystallographic Structure ◽  
High Dose ◽  
Electron Dose ◽  
Dose Rates ◽  
First Case ◽  
Diffraction Patterns ◽  
The Many

Diffraction studies in polymeric and other beam sensitive materials may bring to mind the many experiments where diffracted intensity has been used as a measure of the electron dose required to destroy fine structure in the TEM. But this paper is concerned with a range of cases where the diffraction pattern itself contains the important information.In the first case, electron diffraction from paraffins, degraded polyethylene and polyethylene single crystals, all the samples are highly ordered, and their crystallographic structure is well known. The diffraction patterns fade on irradiation and may also change considerably in a-spacing, increasing the unit cell volume on irradiation. The effect is large and continuous far C94H190 paraffin and for PE, while for shorter chains to C 28H58 the change is less, levelling off at high dose, Fig.l. It is also found that the change in a-spacing increases at higher dose rates and at higher irradiation temperatures.

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