X-Ray Diffraction Comparison of Radiation Damage in Rubber

Abstract This paper describes the use of an x-ray diffraction technique to correlate rubber radiation damage with rubber composition. Correlations between radiation damage and composition are useful as guides for the development of superior radiation resistant elastomers to be used as components of mechanical devices installed in high nuclear radiation fields. Rubber which is stretched and irradiated in an inert atmosphere is readily damaged by chain cleavage, manifested by loss of crystallinity, possible thinning, decreased x-ray diffraction intensities and eventual rupture (Figure 1). Loss of diffraction spot intensity was used to measure radiation damage in stretched rubber, and was tantamount to loss of crystallinity with little specimen thinning until just before rupture. Crystalline longevity was determined fur an irradiated “standard” rubber under standardized conditions and for other rubbers which were similar to the standard except for an added or substituted ingredient. A greater crystalline longevity connoted a greater radiation resistance, and the standard was used as 3 basis for comparing radiation resistance and composition.

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Radiation damage from long-term alpha particle bombardment of silicates – a microfocus XRD and Fe K-edge XANES study

Mineralogical Magazine ◽

10.1180/minmag.2015.079.6.20 ◽

2015 ◽

Vol 79 (6) ◽

pp. 1455-1466 ◽

Cited By ~ 4

Author(s):

W. R. Bower ◽

C. I. Pearce ◽

G. T. R. Droop ◽

J. F. W. Mosselmans ◽

K. Geraki ◽

...

Keyword(s):

Radiation Damage ◽

Ion Irradiation ◽

X Ray Diffraction ◽

X Ray ◽

Radiation Fields ◽

Mineral Phases ◽

Particle Damage ◽

X Ray Absorption ◽

Defect Densities

AbstractA detailed understanding of the response of mineral phases to the radiation fields experienced in a geological disposal facility (GDF) is currently poorly constrained. Prolongued ion irradiation has the potential to affect both the physical integrity and oxidation state of materials and therefore may alter a structure's ability to react with radionuclides. Radiohalos (spheres of radiation damage in minerals surrounding radioactive (α-emitting) inclusions) provide useful analogues for studying long term α-particle damage accumulation. In this study, silicate minerals adjacent to Th- and U-rich monazite and zircon were probed for redox changes and long/short range disorder using microfocus X-ray absorption spectroscopy (XAS) and high resolution X-ray diffraction (XRD) at Beamline I18, Diamond Light Source. Fe3+ → Fe2+ reduction has been demonstrated in an amphibole sample containing structural OH– groups – a trend not observed in anhydrous phases such as garnet. Coincident with the findings of Pattrick et al. (2013), the radiolytic breakdown of OH– groups is postulated to liberate Fe3+ reducing electrons. Across all samples, high point defect densities and minor lattice aberrations are apparent adjacent to the radioactive inclusion, demonstrated by micro-XRD.

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Radiation damage studies in cardiac muscle cells and tissue using microfocused X-ray beams: experiment and simulation

Journal of Synchrotron Radiation ◽

10.1107/s1600577519006817 ◽

2019 ◽

Vol 26 (4) ◽

pp. 980-990 ◽

Cited By ~ 5

Author(s):

Jan-David Nicolas ◽

Sebastian Aeffner ◽

Tim Salditt

Keyword(s):

Cardiac Muscle ◽

Radiation Damage ◽

Muscle Cells ◽

Soft Materials ◽

X Ray Diffraction ◽

Cardiac Muscle Cells ◽

X Ray ◽

Experimental Parameters ◽

Radiation Resistant ◽

The Impact

Soft materials are easily affected by radiation damage from intense, focused synchrotron beams, often limiting the use of scanning diffraction experiments to radiation-resistant samples. To minimize radiation damage in experiments on soft tissue and thus to improve data quality, radiation damage needs to be studied as a function of the experimental parameters. Here, the impact of radiation damage in scanning X-ray diffraction experiments on hydrated cardiac muscle cells and tissue is investigated. It is shown how the small-angle diffraction signal is affected by radiation damage upon variation of scan parameters and dose. The experimental study was complemented by simulations of dose distributions for microfocused X-ray beams in soft muscle tissue. As a simulation tool, the Monte Carlo software package EGSnrc was used that is widely used in radiation dosimetry research. Simulations also give additional guidance for a more careful planning of dose distribution in tissue.

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Techniques for X-Ray Diffraction Studies of Radioactive Materials

Advances in X-ray Analysis ◽

10.1154/s0376030800000574 ◽

1958 ◽

Vol 2 ◽

pp. 261-274

Author(s):

W. V. Cummings ◽

W. J. Gruber

Keyword(s):

Energy Spectrum ◽

Radiation Damage ◽

Background Level ◽

Operating Conditions ◽

Limiting Factor ◽

X Ray Diffraction ◽

Radioactive Materials ◽

High Background ◽

X Ray

AbstractMany materials, both fissionable and non-fissionable, become very radioactive when subjected to nuclear radiations. This radioactivity results in a high background level in X-ray diffraction studies and becomes a limiting factor in an analysis of radiation damage. A description is given of special techniques that are used to minimize this background and produce optimum diffraction conditions. The radioactive intensity of irradiated X-ray specimens varies from levels that are only mildly troublesome to levels that are extremely hazardous to personnel. The diffraction methods employed at the various levels are explained. An example of the radioactive energy spectrum of a specimen is given to show the method of selecting the best operating conditions and techniques.

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A high resolution triple axis X-ray diffraction analysis of radiation damage in lysozyme crystals

Journal of Crystal Growth ◽

10.1016/s0022-0248(01)01089-2 ◽

2001 ◽

Vol 232 (1-4) ◽

pp. 502-510 ◽

Cited By ~ 5

Author(s):

Heather M Volz ◽

Richard J Matyi

Keyword(s):

High Resolution ◽

Diffraction Analysis ◽

Radiation Damage ◽

X Ray Diffraction ◽

X Ray ◽

Lysozyme Crystals

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X-Ray Investigation of a 2H-3C Phase-Transformation in Silicon Carbide Single Crystals

Advances in X-ray Analysis ◽

10.1154/s0376030800008296 ◽

1970 ◽

Vol 14 ◽

pp. 67-77 ◽

Cited By ~ 5

Author(s):

P. Krishna ◽

R. C. Marshall

Keyword(s):

Phase Transformation ◽

Hydrogen Reduction ◽

Reciprocal Lattice ◽

Inert Atmosphere ◽

X Ray Diffraction ◽

X Ray ◽

Hexagonal Close Packed ◽

Dark Green ◽

New Phase ◽

Thermal Stability Of

AbstractThis paper reports the results of a detailed X-ray diffraction study of a new phase-transformation observed in SiC crystals grown by a vapour-liquid-solid mechanism involving the hydrogen-reduction of methyltrichlorosilane. The 10.ℓ reciprocal lattice rows of these crystals, as recorded on X-ray diffraction photographs, reveal sharp reflections corresponding to the hexagonal close-packed 2H (ABAB….) structure and sometimes also corresponding to the cubic close-packed 3C (ABCABC…) structure. These reflections are invariably connected by a diffuse but continuous streak whose intensity is a measure of the random faulting on the basal planes. The crystals were needle shaped and the structure sometimes varied along their length.Several crystals were annealed in an inert atmosphere at progressively higher temperatures and their 10.ℓ reciprocal lattice row re-examined to determine the annealing behaviour as well as possible structural transformations. For a number of dark green needles having a faulted 2H structure the 2H reflections disappeared around 1400° C and the 10.ℓ reciprocal lattice row revealed only a continuous streak with increased intensity around positions for 3C reflections. On further heating the structure went over to a strongly faulted 3C. Around 1600°C the appearance of a 6H structure became discernible while highly diffuse 30 reflections still persisted. The reversible part of the transformations, if any, could not be observed. Some of the structures were, however, found to be much more stable and did not transform even up to 1650° C.The above results, in particular the discovery of a 2H-3C phase-transformation around 1400°C, throw fresh light on the thermodynamic stability of the different SiC types. The mechanism of the 2H-3C transformation, the possible influence of faults and impurities and the thermal stability of various SiC structures are discussed on the basis of the experimental results stated above.

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Instrumentation for X-Ray Diffraction Studies of Highly Radioactive Samples

Advances in X-ray Analysis ◽

10.1154/s037603080000046x ◽

1958 ◽

Vol 2 ◽

pp. 107-115

Author(s):

Vincent G. Scotti ◽

James I. Mueller ◽

John J. Little

Keyword(s):

Radiation Damage ◽

Gamma Ray ◽

Pulse Height ◽

Fission Products ◽

Analytical Tool ◽

Nuclear Engineering ◽

X Ray Diffraction ◽

X Ray ◽

Background Ratio ◽

Gamma Ray Irradiation

AbstractWith the advent of nuclear engineering, x-ray diffraction has become an important analytical tool in the study of radiation damage due to neutron and gamma-ray irradiation. The materials under study in this work have rdioactive levels up to 40 R/hr. at 17 centimeters combined β and γ. The activity of the various samples under study may be due to (n, γ) reactions or fission products or both.Data are presented to illustrate the use of sample shielding, detector shielding pulse height discrimination and the combination of all three aids in an effort to attain the most favorable peak to background ratio.

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Preparation of MgO-Templated N-Doped Mesoporous Carbons from Polyvinylpyrrolidone: Effect of Heating Temperature on Pore Size Distribution

C – Journal of Carbon Research ◽

10.3390/c5020015 ◽

2019 ◽

Vol 5 (2) ◽

pp. 15

Author(s):

Tomoya Takada ◽

Mayu Kurihara

Keyword(s):

Pore Size ◽

Nitrogen Content ◽

Acid Treatment ◽

Heating Temperature ◽

Inert Atmosphere ◽

Raw Material ◽

Mesoporous Carbons ◽

X Ray Diffraction ◽

X Ray ◽

Templated Carbon

Magnesium oxide (MgO)-templated nitrogen (N)-doped mesoporous carbons were prepared by using polyvinylpyrrolidone (PVP) as a raw material and magnesium lactate (Mglac) as a precursor for the MgO template to examine the influence of heating temperature and MgO precursor (magnesium acetate was used in similar previous studies) on the pore size and nitrogen content. The MgO-templated carbon was obtained by heating the PVP/Mglac mixture in an inert atmosphere followed by an acid treatment for MgO removal. The mesopore size of the carbons was approximately 4 nm regardless of heating temperature, corresponding to the crystallite size of the MgO template estimated via X-ray diffraction. This indicates that the mesopore of approximately 4 nm was generated using the MgO template. However, larger pores were also found to exist. This result indicates that the larger pores generated through processes other than the MgO templating, likely the thermal decomposition of PVP, are contained in the templated carbon. The volume of the larger pores and the specific surface area increased with increasing heating temperature. The nitrogen content of the carbon decreased as the heating temperature was increased, but it was found to be irrelevant to the MgO precursor.

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Die Kristallstruktur von Methylquecksilberazid / The Crystal Structure of Methyl Mercury Azide

Zeitschrift für Naturforschung B ◽

10.1515/znb-1973-7-807 ◽

1973 ◽

Vol 28 (7-8) ◽

pp. 426-428 ◽

Cited By ~ 10

Author(s):

Ulrich Müller

Keyword(s):

Crystal Structure ◽

Radiation Damage ◽

Diffraction Data ◽

Methyl Mercury ◽

Unit Cell ◽

Outer Side ◽

Methyl Groups ◽

X Ray Diffraction ◽

Space Group ◽

X Ray

CH3HgN3 crystallizes in the space group P21/c with four molecules per unit cell. The structure was solved by common crystallographic methods using X-ray diffraction data that were collected at a temperature of 100°K. The cooling was necessary to limit the radiation damage of the crystals. The molecules possess an essentially linear C-Hg-N group; in the crystals they are associated to layers bearing the methyl groups on their outer side.

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Inorganic matrices for immobilization of Tc-99

MRS Proceedings ◽

10.1557/proc-1193-33 ◽

2009 ◽

Vol 1193 ◽

Cited By ~ 2

Author(s):

Yulia I. Korneyko ◽

Vladimir M. Garbuzov ◽

Olga V. Schmidta ◽

Boris E. Burakov

Keyword(s):

Metallic Phase ◽

Inert Atmosphere ◽

X Ray Diffraction ◽

X Ray ◽

Synthesis Conditions ◽

Mn Oxide ◽

Ceramic Synthesis ◽

Reducing Conditions ◽

Metallic Inclusions ◽

Inorganic Matrices

AbstractImmobilization of long-lived 99Tc requires development of chemically resistant inorganic matrices. Samples of ceramics based on crystalline Fe-Mn- and Zr-Mn-oxide compounds were synthesized at 1150°C in air, reducing or inert atmosphere from precursors doped with 5-12 wt.% Tc. All the samples obtained were studied using optical and scanning electron microscopy (SEM); powder X-ray diffraction (XRD) and microprobe analysis (EMPA). Content of Tc varied from 0.5-0.8 to 3-6 wt.% in oxide host phases and from 54 to 93 wt.% in metallic inclusions. It was demonstrated that synthesis of oxide host-phases under oxidizing or reducing conditions was not optimal due to partial Tc volatilization or metallic phase formation, respectively. The use of inert atmosphere for ceramic synthesis supports Tc incorporation into crystalline structure of stable host-phases. Development of optimal methods of precursor preparation and synthesis conditions of Tc-doped ceramic are being discussed.

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