Change in Radiation Sterilization Process from Gamma Ray to X-ray

2021 ◽  
Vol 55 (s3) ◽  
pp. 78-84
Author(s):  
Christiane Beerlage ◽  
Bjoern Wiese ◽  
Annemie Rehor Kausch ◽  
Milorad Arsenijevic

Abstract The terminal sterilization of sterile orthopedic implants is a key process that, in addition to providing sterility, changes the material properties of the product and packaging. These changes might be observed during functionality testing and/or biological evaluation. We are establishing an additional sterilization process that appears promising from both a technical and business perspective. Our project aims to add X-ray sterilization to the established gamma sterilization for metallic hip and shoulder implants. To limit complexity, we started with a narrow product range. The main steps of our project journey are described here. Given that X-ray sterilization remains relatively new in terms of understanding the changes that might occur for product materials and functionality compared with changes observed following gamma radiation processing, this article highlights key steps in the change from gamma ray to X-ray sterilization.

2021 ◽  
Vol 55 (s3) ◽  
pp. 58-66
Author(s):  
Alan Montgomery ◽  
Romain Bolle-Reddat ◽  
Shari Formica ◽  
Bradley Lundahl ◽  
Gerald McDonnell

Abstract When investing in X-ray irradiation facilities around the world, an opportunity exists for defining a regulatory framework for assessing the transition from current gamma irradiation processes. Historically, regulatory strategies for changing the radiation source for routine processing has consisted of repeating the majority, if not all, of the validation activities performed as part of an initial validation and associated submission. Although not a new concept, performing a risk assessment has the potential to be leveraged more fully by increasing the rigor of determining what is changing when product moves from a gamma to an X-ray irradiator, then determining how these differences may affect product characteristics. During these steps, differences can be identified and quantified between radiation sources and potential impacts, if any, to product quality can be elucidated. Based on these risk assessments, the level of action required, or not required, in terms of empirical product testing can be examined and a determination can be made regarding whether a substantial change has occurred.


1997 ◽  
Vol 487 ◽  
Author(s):  
H. Hermon ◽  
R. B. James ◽  
J. Lund ◽  
E. Cross ◽  
A. Antolak ◽  
...  

AbstractIn this study we report on the results of the investigation of lead iodide material properties. The effectiveness of a zone refining purification method on the material purity is determined by ICP-MS and ICP-OES and correlated to the electrical and physical material properties. We show that this zone refining method is very efficient in removing impurities from lead iodide, and we also determine the segregation coefficient for some of these impurities. Triple axis x-ray diffraction (TAD) analysis has been used to determine the crystalline perfection of the lead iodide after applying various cutting, etching and fabrication methods. The soft lead iodide crystal was found to be damaged when cleaved by a razor blade, but by using a diamond wheel saw, followed by etching, the crystallinity of the material was much improved, as observed by TAD. Low temperature photoluminescence also indicates an improvement in the material properties of the purified lead iodide. Electrical properties of lead iodide such as carrier mobility, were calculated based on carrier - phonon scattering. The results for the electrical properties were in good agreement with the experimental data.


1987 ◽  
Vol 48 (C9) ◽  
pp. C9-367-C9-370
Author(s):  
C. B. COLLINS ◽  
F. DAVANLOO ◽  
T. S. BOWEN ◽  
J. J. COOGAN
Keyword(s):  

2003 ◽  
Vol 8 (5-6) ◽  
pp. 60-64
Author(s):  
A.I. Arkhangelsky ◽  
◽  
Yu.D. Kotov ◽  
P.Yu. Chistiakov ◽  
◽  
...  

1998 ◽  
Vol 502 (1) ◽  
pp. 428-436 ◽  
Author(s):  
Igor V. Moskalenko ◽  
Werner Collmar ◽  
Volker Schonfelder

1996 ◽  
Vol 165 ◽  
pp. 313-319
Author(s):  
Mark H. Finger ◽  
Robert B. Wilson ◽  
B. Alan Harmon ◽  
William S. Paciesas

A “giant” outburst of A 0535+262, a transient X-ray binary pulsar, was observed in 1994 February and March with the Burst and Transient Source Experiment (BATSE) onboard the Compton Gamma-Ray Observatory. During the outburst power spectra of the hard X-ray flux contained a QPO-like component with a FWHM of approximately 50% of its center frequency. Over the course of the outburst the center frequency rose smoothly from 35 mHz to 70 mHz and then fell to below 40 mHz. We compare this QPO frequency with the neutron star spin-up rate, and discuss the observed correlation in terms of the beat frequency and Keplerian frequency QPO models in conjunction with the Ghosh-Lamb accretion torque model.


2021 ◽  
Vol 366 (4) ◽  
Author(s):  
Zhi-Ying Liu ◽  
Fu-Wen Zhang ◽  
Si-Yuan Zhu

Galaxies ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 36
Author(s):  
Yoshiyuki Inoue ◽  
Dmitry Khangulyan ◽  
Akihiro Doi

To explain the X-ray spectra of active galactic nuclei (AGN), non-thermal activity in AGN coronae such as pair cascade models has been extensively discussed in the past literature. Although X-ray and gamma-ray observations in the 1990s disfavored such pair cascade models, recent millimeter-wave observations of nearby Seyferts have established the existence of weak non-thermal coronal activity. In addition, the IceCube collaboration reported NGC 1068, a nearby Seyfert, as the hottest spot in their 10 yr survey. These pieces of evidence are enough to investigate the non-thermal perspective of AGN coronae in depth again. This article summarizes our current observational understanding of AGN coronae and describes how AGN coronae generate high-energy particles. We also provide ways to test the AGN corona model with radio, X-ray, MeV gamma ray, and high-energy neutrino observations.


Sign in / Sign up

Export Citation Format

Share Document