scholarly journals Resurgence of a Nation’s Radiation Science Driven by Its Nuclear Industry Needs

2021 ◽  
Vol 11 (23) ◽  
pp. 11081
Author(s):  
Laura Leay ◽  
Aliaksandr Baidak ◽  
Christopher Anderson ◽  
Choen May Chan ◽  
Aaron Daubney ◽  
...  
Keyword(s):  
Polymeric Materials ◽  
Radiation Chemistry ◽  
Nuclear Industry ◽  
Nuclear Materials ◽  
Cooling Systems ◽  
Gaseous Products ◽  
Material Chemistry ◽  
Radiation Induced ◽  
Radiation Science ◽  
Industry Needs

This article describes the radiation facilities and associated sample preparation, management, and analysis equipment currently in place at the Dalton Cumbrian Facility, a facility which opened in 2011 to support the UK’s nuclear industry. Examples of measurements performed using these facilities are presented to illustrate their versatility and the breadth of research they make possible. Results are presented from research which furthers our understanding of radiation damage to polymeric materials, radiolytic yield of gaseous products in situations relevant to nuclear materials, radiation chemistry in light water reactor cooling systems, material chemistry relevant to immobilization of nuclear waste, and radiation-induced corrosion of fuel cladding elements. Applications of radiation chemistry relevant to health care are also described. Research concerning the mechanisms of radioprotection by dietary carotenoids is reported. An ongoing open-labware project to develop a suite of modular sample handling components suited to radiation research is described, as is the development of a new neutron source able to provide directional beams of neutrons.

scholarly journals Modification of ethylene-norbornene copolymer by Gamma irradiation

2006 ◽  
Vol 60 (11-12) ◽  
pp. 311-315 ◽  
Author(s):  
Zorica Kacarevic-Popovic ◽  
Bojana Secerov ◽  
Milena Marinovic-Cincovic ◽  
Zoran Nedic ◽  
Slobodan Jovanovic
Keyword(s):  
Gamma Irradiation ◽  
Radiation Chemistry ◽  
High Energy ◽  
Spectrophotometric Analysis ◽  
New Combination ◽  
Polymeric Systems ◽  
New Class ◽  
Radiation Induced ◽  
Dsc Method ◽  
Induced Changes

The possibility of modifying polyethylene and many other polymers with high energy radiation has led to many useful applications. Due to their new combination of properties and the shortage of experimental data, the radiolysis of a new class of materials, cyclo-olefin copolymers (COC), polymerised from norbornene and ethylene using metallocene catalysts, is of great interest to the study of radiation chemistry and the physics of polymeric systems. Ethylenenorbornene copolymer, pristine and containing an antioxidant were subjected to gamma irradiation in the presence of air and in water. The irradiated copolymer was studied using IR and UV-vis spectrophotometric analysis. The radiation-induced changes in the molecular structure were correlated to changes in the glass transition temperature measured by the DSC method.

Network engineering education: Prospects for the implementation of the Worldwide CDIO Initiative in nuclear areas

2020 ◽  
Vol 34 (6) ◽  
pp. 440-445
Author(s):  
Nikolay I. Geraskin ◽  
Andrey A. Krasnoborodko ◽  
Vasily B. Glebov
Keyword(s):  
Engineering Education ◽  
Empirical Research ◽  
Feasibility Study ◽  
Nuclear Industry ◽  
Nuclear Materials ◽  
Specialist Training ◽  
Educational Challenges ◽  
Safe Management ◽  
Network Engineering ◽  
Network Form

This article summarises the results of a preliminary feasibility study and the experience of implementing Conceive-Design-Implement-Operate (CDIO) ideas during 2016–2019 in the education of nuclear specialists. The study is a form of empirical research. The results and findings regarding implementation of the CDIO approach are presented in relation to the Russia–Kazakhstan network programme of specialist training for the nuclear industry of Kazakhstan. The authors conclude that CDIO ideas effectively promote solutions to educational challenges facing the nuclear industries of specific countries. Key findings are (a) that the network form of education is well-suited to the implementation of the CDIO approach and (b) that the principle of the safe management of nuclear materials should be considered in the context of engineering education.

Robotics in Nuclear Materials Processing at LANL: Capabilities and Needs

2009 ◽  
Author(s):  
Cameron J. Turner ◽  
Troy A. Harden ◽  
Jane A. Lloyd
Keyword(s):  
Material Handling ◽  
National Laboratory ◽  
Nuclear Material ◽  
Nuclear Industry ◽  
Nuclear Materials ◽  
Automated Systems ◽  
Los Alamos National Laboratory ◽  
Materials Handling ◽  
Automation Systems ◽  
Manual Tasks

Nuclear material processing operations present numerous challenges for effective automation. Confined spaces, hazardous materials and processes, particulate contamination, radiation sources, and corrosive chemical operations are but a few of the significant hazards. However, automated systems represent a significant safety advance when deployed in place of manual tasks performed by human workers. The replacement of manual operations with automated systems has been desirable for nearly 40 years, yet only recently are automated systems becoming increasingly common for nuclear materials handling applications. This paper reviews several automation systems which are deployed or about to be deployed at Los Alamos National Laboratory for nuclear material handling operations. The needs that resulted in the development of these systems can be found throughout the nuclear industry. Highlighted are the current social and technological challenges faced in deploying automated systems into hazardous material handling environments and the opportunities for future innovations.

Chemico-Physical Causes of Radiation-Induced “Long Cell” Action Corrosion in Water Cooled Reactors

2010 ◽  
Author(s):  
Genn Saji
Keyword(s):  
Chemical Potential ◽  
Cooling System ◽  
Radiation Chemistry ◽  
Potential Difference ◽  
Equilibrium Potential ◽  
Corrosion Mechanism ◽  
Hydrated Electrons ◽  
Standard Chemical Potential ◽  
Radiation Induced ◽  
Reactor Types

In the previous overview papers [1, 2], the author has identified that ‘long cell action’ corrosion plays a pivotal role in practically all unresolved corrosion issues, irrespective of reactor types and operation. In trying to confirm the existence of radiation-induced ‘long-cell’ action (macro) corrosion cell in the primary cooling system of LWRs, the author attempted to theoretically reproduce the electrochemical potential difference demonstrated during experiments at the INCA Loop in Sweden and the NRI-Rez Loop in the Czech Republic [3, 4]. By performing a radiation chemistry kinetics study combined with electrochemistry calculations, the hydrated electrons, e−aq, reacting mainly with stable molecules, are found to be responsible for inducing a large portion of the potential difference both in the PWR and BWR water chemistry environment. Considering large uncertainties, the author used the standard equilibrium potential as a fitting parameter in the previous studies [3, 4]. The standard chemical potential of the hydrated electron estimated from the fitting parameter is far less than the generally accepted value of 2.86 V. In order to resolve the large discrepancy between the generally accepted values and the estimation from the fitting parameter, the author has developed a ‘mixed’ radiation-electrochemistry formalism, which enables theoretical reconstruction of the observed potential differences more clearly. The previous verifications are updated by using this approach. Through these studies, the author has confirmed the existence of the ‘long cell’ action corrosion mechanism existing in the water-cooled reactors.

Safety Assessment of Fuel Storage Ponds Following Cooling Faults

2016 ◽  
Author(s):  
Jonathan Webb ◽  
Charles Bridgford
Keyword(s):  
Nuclear Power ◽  
Structural Integrity ◽  
Spent Nuclear Fuel ◽  
Nuclear Safety ◽  
Nuclear Industry ◽  
Spent Fuel ◽  
Cooling Systems ◽  
External Cooling ◽  
Safety Case

For spent nuclear fuel stored within a cooling pond, the essential nuclear safety functions of control, cooling and containment are fulfilled by maintaining an appropriate depth of water above the fuel. External cooling systems remove the decay heat generated by the spent fuel stored within the pond, in order to maintain the temperature of the water at a constant level. In the event of a fault within these external cooling systems, there is the potential for a temperature excursion within the pond. Historically the UK nuclear industry has considered that such faults would pose no threat to the structural integrity of the pond containment and hence the only loss of water would be due to evaporation following a loss of cooling. However, more recently, it has been recognised that such temperature excursions may result in through-wall cracking leading to a loss of water and undermining of these essential safety functions. This paper outlines the safety case implications of these realisations and the way in which they are being addressed within the UK’s nuclear power stations. The paper considers the effects of thermal transient faults on the concrete pond structure and the potential nuclear safety issues which may occur as a result of this. In response to potential pond cooling faults, consideration is given to the requirement for engineered protection systems along with the safety role of the operator in identifying and responding to faults of this kind. Operators provide a versatile mechanism for identifying fault conditions and taking remedial actions, however, the benefit which can be formally claimed for their role within a safety case is generally limited by the availability or reliability of instrumentation to reveal a fault condition. Post fault operator actions may also be limited by the timescales available following a fault, or by other demands on the operators, which may occur in the event of an external hazard which affects multiple site systems. To quantify the timescales available for post fault remedial action, it is necessary to quantify the rate of water loss from the pond, along with the relationship between pond water depth and the radiological consequences both on-site and off-site. This paper investigates the difficulties which may be encountered in quantifying the role of post fault operator actions within such a safety case, and in demonstrating that the overall nuclear safety risk is acceptably low and as low as reasonably practicable (ALARP).

scholarly journals Diffraction data analysis in the presence of radiation damage

2010 ◽  
Vol 66 (4) ◽  
pp. 426-436 ◽  
Author(s):  
Dominika Borek ◽  
Marcin Cymborowski ◽  
Mischa Machius ◽  
Wladek Minor ◽  
Zbyszek Otwinowski
Keyword(s):  
Data Analysis ◽  
Crystal Lattice ◽  
Diffraction Data ◽  
Radiation Chemistry ◽  
Lattice Order ◽  
Specific Chemical ◽  
Crystal Forms ◽  
High Cumulative Dose ◽  
Radiation Induced ◽  
Induced Changes

In macromolecular crystallography, the acquisition of a complete set of diffraction intensities typically involves a high cumulative dose of X-ray radiation. In the process of data acquisition, the irradiated crystal lattice undergoes a broad range of chemical and physical changes. These result in the gradual decay of diffraction intensities, accompanied by changes in the macroscopic organization of crystal lattice order and by localized changes in electron density that, owing to complex radiation chemistry, are specific for a particular macromolecule. The decay of diffraction intensities is a well defined physical process that is fully correctable during scaling and merging analysis and therefore, while limiting the amount of diffraction, it has no other impact on phasing procedures. Specific chemical changes, which are variable even between different crystal forms of the same macromolecule, are more difficult to predict, describe and correct in data. Appearing during the process of data collection, they result in gradual changes in structure factors and therefore have profound consequences in phasing procedures. Examples of various combinations of radiation-induced changes are presented and various considerations pertinent to the determination of the best strategies for handling diffraction data analysis in representative situations are discussed.

scholarly journals Initiation Parameters of Granulated Synthetic Polymers

2021 ◽  
Vol 29 (48) ◽  
pp. 114-122
Author(s):  
Peter Rantuch ◽  
Jozef Martinka ◽  
Tomáš Štefko ◽  
Igor Wachter
Keyword(s):  
Heat Flux ◽  
Polymeric Materials ◽  
Synthetic Polymers ◽  
Flow Time ◽  
External Heat ◽  
Small Thickness ◽  
Gaseous Products ◽  
Product Method ◽  
Different Shapes ◽  
External Heat Flux

Abstract Polymeric materials, which are currently very often used in various industries, are often transported and stored in the form of granules before processing. This method has several advantages, but in most studies the test samples are modified to different shapes and dimensions. This paper is therefore focused on the initiation of selected granular plastics. Samples of five polymeric materials were exposed to an external heat flux from 20 kW.m−2 to 40 kW.m−2. A spark initiator was used to ignite the released gaseous products of thermal decomposition of the polymer sample. FTP (flow-time product) method was applied to the obtained parameter - time to ignition, from which other initiation parameters were determined. The critical heat flux was determined in the range of 5.0 kW.m−2 - 11.8 kW.m−2. Despite the relatively small thickness (4 mm), the samples behaved as thermally thick. During the measurement, thin surface layer melted, and the rest of the polymer remained in its original granulated form. Ignition temperatures were calculated according to the Stefan-Boltzmann’s law between 273 °C - 402 °C.

Best Practices and Lessons Learned from Nuclear Materials Retrieval Programs of the United States Department of Energy

2020 ◽  
Author(s):  
Kaatrin Abbott ◽  
Zachary Geroux
Keyword(s):  
United States ◽  
Best Practices ◽  
Economic Value ◽  
The United States ◽  
Nuclear Material ◽  
Lessons Learned ◽  
Nuclear Industry ◽  
Department Of Energy ◽  
Nuclear Materials ◽  
United States Department

Abstract The Atomic Energy Act, as amended, authorizes the United States (U.S.) Department of Energy (DOE) and its predecessor agencies to distribute nuclear materials to public or private institutions for the purposes of education as well as research and development. Significant transformations throughout the nuclear industry have led to changes in programmatic responsibility for loaned nuclear materials. DOE has established several programs to catalog, transfer ownership, retrieve, and/or dispose of these loaned nuclear materials. The variety of loaned nuclear material types, as well as operational and regulatory variations between facility licensees have created unique challenges for the retrieval and dispositioning processes. These include packaging and transportation, confirmation of regulatory jurisdiction, property transfer, and disposal of sources with no remaining economic value. This paper explores the methods and actions taken by DOE to address these challenges. Lessons learned and best practices identified from these programs are also presented.

Sign in / Sign up

Export Citation Format

Share Document