bluuebunny/crossref_metadata_2025 huggingface dataset:
High-Level-Waste and Spent Fuel Storage in Switzerland
Authors: Sach Udo , Schreck Goswin , Ritter Max , Wenger Jean-Pierre
Published: April 2020

At present, Switzerland has no final repository for radioactive wastes. Very early, the Swiss nuclear power plant operators were aware of the necessity to expand interim storage capacity for spent fuel elements and operational wastes. Already in 1991, Nordostschweizerische Kraftwerke AG (NOK) therefore started building a reactor-site interim storage facility (ZWIBEZ) at its Beznau power plant site.

Moreover, as early as in 1990, “ZWILAG Zwischenlager Würenlingen AG”, a company established by the nuclear power plant operators had initiated the licensing procedure for a central interim storage facility in Switzerland. This central interim storage facility is designed for the storage of all categories of radioactive wastes and includes a conditioning facility for low-level and medium-level waste. Eleven years later, in July 2001, the first transport and storage cask loaded with irradiated fuel elements was stored in this facility.

For both of the stores the concept of dry interim storage in suitable storage casks in a storage hall was chosen for the storage of irradiated fuel elements and vitrified high-level wastes from reprocessing. Cooling is established through natural circulation. Leaktightness of the casks is continuously monitored by means of a cask monitoring system.

The other wastes arising from nuclear power plant operation and reprocessing are stored in a ventilated storage hall which provides shielding and — depending on the radioactive inventory — protection against external impact. The conditioned radioactive wastes, packaged in drums, are placed into open storage containers with identical base and having the same sling points as ISO containers. These containers are stacked up in free-standing stacks up to a height of 16 m. The storage concept varies, depending on the radioactive inventory; for the ZWIBEZ reactor-site interim store, a storage hall for low-level waste has been built without partition walls, whereas the store for the medium and high-level waste in the central interim store ZWILAG has been designed with partition walls dividing the hall into several storage shafts which are closed by shielding slabs.

By including a hot cell into the ZWILAG facility, the purpose of this facility has been expanded beyond interim storage of radioactive waste to cover also the visual inspection of fuel elements and vitrified waste canisters as well as the reloading of fuel elements and canisters from smaller transport casks into combined transport and storage casks. Furthermore, the hot cell enables inspection and/or repair work to be performed in the cask lid area of loaded transport and storage casks, the replacement of the lid seals of storage casks and the conditioning of medium-level waste.
Fundamental Principles of and Reactions to the June 2001 Enviromental Radiation Protection Standards for the Yucca Mountain Site
Authors: Monroe Scott D. , Schultheisz Dan
Published: April 2020

On June 13, 2001, the United States Environmental Protection Agency (USEPA) issued final public health and environmental radiation protection standards for the proposed spent nuclear fuel and high-level radioactive waste repository at Yucca Mountain, Nevada. The Energy Policy Act of 1992 (EnPA) had directed USEPA to develop these standards for the Yucca Mountain site.
Oxidation of Organic Radioactive Waste by Electrochemical Mediation
Authors: Cantrel E. , Fonteyne A. , Impens N. , Rahier A.
Published: April 2020

Liquid as well as solid organic radioactive waste can be processed by means of combustion. However, this method presents several well-known drawbacks including the corrosion of the ovens, the production of radioactive ashes and radioactive or toxic volatile products. The electrochemical mediation process is an excellent alternative to combustion, especially when dealing with hazardous materials such as explosives, pesticides, drugs and nuclear organic waste. Nevertheless, using the silver(II) species as electrogenerated mediator, requires to work in concentrated nitric acid media, which results, via its electrolysis, in a continuous NOx emission. The classical approach, using absorption columns and scrubbers to trap NOx, impairs the attractiveness of this process. Therefore the SCK•CEN has developed and patented an original method to suppress in-situ any formation of NOx, conferring the process mobility and compactness.
Standards and Specifications for Packaging Waste in the UK
Authors: Barlow S. V. , Palmer J. D.
Published: April 2020

The role of Nirex is to provide the United Kingdom with safe and environmentally sound options for the long-term management of radioactive waste generated by the UK’s commercial, medical, research and defence activities. This includes all intermediate level waste and some low level waste (ILW and LLW). One of the key objectives of Nirex over the past 10 years or so, has been to ensure that when waste is packaged, it is in a form suitable for its future safe management including storage, transport, handling and potential disposal.

Being responsible for development of future long-term waste management facilities, Nirex is uniquely placed to define standards and performance specifications for waste packages that include wasteform and container design, quality assurance and data recording requirements. In addition to the specifications, Nirex also provides detailed advice on the suitability of specific packaging proposals and plant designs against the foreseen requirements for future transport, handling, storage and potential disposal, as defined by the Nirex phased disposal concept. Where packaging proposals meet these requirements, Nirex is prepared to endorse the proposed approach through the issue of a ‘Letter of Comfort’.

This approach has enabled the commencement of waste packaging operations with a high degree of confidence that the waste product will meet future waste management requirements, including potential disposal requirements. This paper provides a summary of the standards and specifications developed by Nirex for waste packages, and of the assessment process applied by Nirex in providing advice and endorsement of specific packaging proposals.
Performance Assessment of Mochovce Repository: A Comparison of Two Modeling Approaches
Authors: Hanušík Václav , Kusovská Zdena , Volckaert Geert , Gedeon Matej
Published: April 2020

The calculations for performance assessment of the Mochovce Radioactive Waste Disposal Facility in Slovakia were made by means of modified computer codes MODEMO, NUCDSLB and LAKE. During recent years computer codes DUST-MS, MODFLOW/MT3DMS and BS for source term, ground water flow and transport of radionuclides through ground water and biosphere respectively were implemented in the framework of the performance assessment iterative process. This paper describes results of comparison of the both approaches for source term and groundwater flow.
Source Term Assessment: The ARIANE Programme
Authors: Lippens Marc , Boulanger Danièle , Basselier Jacques , Van Winckel Stefaan , Wernli Beat , Betti Maria
Published: April 2020

The prediction of the source term of actinides, fission and activation products is of major importance in numerous nuclear fields. An experimental programme of radiochemistry (called ARIANE) was carried out on MOX and UO2 fuels irradiated in PWR and BWR conditions, reaching burnups of 35 up to 55 GWd/tM. Besides the providing of a large set of experimental data on the irradiated fuel inventory, a second objective of the programme was to confer on these experimental results reliable and minimised uncertainties.

About 50 isotopes of actinides and fission products were selected. Their contents were measured using techniques as TIMS, ICP-MS, alpha, beta and gamma spectrometry. The measurement results were crosschecked by three highly qualified laboratories and recommended values were provided after extended analysis and confrontation of the results. For most of the measured isotopes, the target uncertainties were reached and even reduced, providing a unique database for irradiated fuel characterisation and for code qualification.
Crystalline Ceramics Developed for the Immobilization of Actinide Wastes in Russia
Authors: Burakov Boris E. , Anderson Evgeniy B.
Published: April 2020

It is proposed that only ceramics, which are based on host-phases similar to naturally occurring accessory minerals including zircon, (Zr,Hf,An,…)SiO4; hafnon, (Hf,Zr,An,…)SiO4; baddeleyite, (Zr,Hf,An,…)O2; tazheranite (cubic zirconia), (Zr,Hf,Ca,Ti,An,…)O2; garnet, (Ca,Fe,Gd,An,…)3(Al,Fe,Si,An,…)5O12 and perovskite, (Ca,Gd,An,…)(Al,Fe,Ti,…)O3, are the most suitable materials for actinide (An = U, Pu, Np, Am, Cm) isolation in deep geological formations. Solid solution of Pu in cubic zirconia, (Zr,Pu)O2, could be used as ceramic nuclear fuel which is competitive with mixed oxide fuel, (U,Pu)O2. Samples of these ceramics doped with Pu from a few % to 37 wt. % El. were successfully synthesized and investigated. Physical and chemical properties of synthesized ceramics, and the industrial scale applications of these suggested waste forms, are discussed.
Two Periods of Long-Term Storage of Thorium Spent Fuel
Authors: Gerasimov Aleksander S. , Bergelson Boris R. , Zaritskaya Tamara S.
Published: April 2020

Radiotoxicity and decay heat power of actinides from spent thorium-uranium nuclear fuel of VVER-1000 type reactor during 100 000 year storage are discussed. Actinide accumulation in thorium fuel cycle is much less than in uranium fuel cycle. The radiotoxicity of actinides of thorium-uranium fuel by air is 5.5 times less and radiotoxicity by water is 3.5 times less than radiotoxicity of actinides of uranium fuel. Extraction of most important nuclides for transmutation permits to reduce radiologic danger of wastes remaining in storage.
The Dismantling of Primary and Auxiliary Loops of the BR3-PWR Reactor: From On Site Decontamination up to Final Evacuation of the Dismantled Materials
Authors: Klein Michel , Valenduc Pierre , Vermeersch Fernand , Davain H.
Published: April 2020

SCK•CEN is dismantling its small BR3 PWR reactor. For the management of the contaminated loops, we decided first to decrease the dose rate by a chemical decontamination of the circuits. A complete dismantling of the loops and of the equipment’s follows this. After a careful sorting of the pieces, we select the optimised management route, which will lead to a minimum of radioactive waste disposed. This paper gives the results of the management of the pieces arising from the dismantling of the most contaminated loops of the plant. We show that it is possible to recycle most of the metallic materials either in the nuclear world or in the industrial world by reaching the respective recycling or clearance criteria.
Decommissioning of a Plutonium-Contaminated Waste Incinerator Facility (I)
Authors: Uematsu Shinichi , Tobita Noriyuki , Koakutsu Toru
Published: April 2020

A plutonium-contaminated waste incinerator facility (PWIF) was operated from 1983 to 1989 to demonstrate the treatment of combustible plutonium-contaminated wastes from MOX fuel production facilities in Tokai works of the former Power Reactor and Nuclear Fuel Development Corporation (PNC). PWIF has following features: 1) Silicon carbide cakes (approximately 300kg) were filled in the incinerator. 2) The incinerator had the multi-layer structure, and the plutonium-contaminated ashes adhered on the inner surface of the incinerator. 3) The space for dismantling was not maintained sufficiently because the clearances between equipments and walls were very small. It is necessary for decommissioning of PWIF in safety and with rationality to choose optimum dismantling methods and procedures in which these features are considered. Key principles in decommissioning of this facility are 1) Dismantling the main process equipments and gloveboxes in the greenhouses to prevent the scattering of contaminated particles 2) Working with airline suit in the greenhouse to prevent workers from inhaling alpha radioactive nuclides 3) Decreasing the generation of secondary waste. Following methods and procedures were adopted:

• Step I Creating the space for dismantling of equipments;

• Step II Performing the pre-treatment for the dismantling of the incinerator;

• Step III Dismantling the glovebox for throwing the wastes into the incinerator, the glovebox for exchanging the high-temperature filter material, and four small gloveboxes for sampling;

• Step IV Dismantling the incinerator and the upper part of the high-temperature filter;

• Step V Dismantling the lower part of the high-temperature filter and two gloveboxes for extracting the ashes and for the absorbing device for sampling;

• Step VI Dismantling the ventilation process.

It was planned that this facility is dismantled from the beginning of May 2000 to the end of December 2001. An absorbing device for extracting the silicon carbide cakes from the incinerator and a remote-controlled device for decontamination of the inner surface of the incinerator were developed. The pre-treatment work was performed by using these devices successfully. The dose rate and the density of radioactive materials in the incinerator were decreased from 180μSv/hr to 90μSv/hr and from 30 Bq/cm2 to 0.5 Bq/cm2 respectively by the pre-treatment. Dismantling of the gloveboxs was carried out in the greenhouse using popular tools (band saws, disk grinders and etc.). Dismantling the incinerator and the high-temperature filter is being carried out from the beginning of December 2000. The whole dismantling works will be accomplished by the end of December 2001.
Management of Tritium Wastes
Authors: Rickard Lee , Weller Frank , Wilks Jeff
Published: April 2020

The paper describes some of the tritium management activities undertaken by AEA Technology at its Winfrith site in Dorset, England. These form part of a wide-ranging commercial service that provides UK industry with a responsible means of managing tritiated materials.

A wide variety of different tritium containing materials is used by industry, or is generated as a by-product of other activities. Some of the main waste management challenges that these materials present are identified and some of the materials are described in more detail. Tritium contamination can take a variety of forms and some of these are briefly described. Two key methods used for decontaminating tritium containing waste, aqueous washing and heat treatment, are discussed.

AEA Technology’s largest tritium management project involves the recovery of around 3,000 TBq of tritium from some 2,000,000 luminous phone dials. This project is described in more detail. The process that has been developed first requires that the tritium-containing source be removed from the surrounding device. Once separated, the source is cleaned and prepared for tritium recovery. The tritium, in diluted form, is recovered form the source by heating to temperatures of 1200°C. The mixture of hydrogen isotopes is separated from other gases present and then passed through an enrichment cycle to raise the tritium concentration to around 99.4%, a concentration suitable for commercial reuse.
Geological Disposal for High-Level Waste: Ethical Considerations
Authors: Cornelis Gustaaf C.
Published: April 2020

This paper describes the activities launched at SCK•CEN, intended to explore ethical and other non-technical aspects when dealing with the time scales considered in the high-level waste disposal program. (1) Especially the issues of retrievability and precaution will be focused on philosophically. Many questions will be raised in order to sensitize all stakeholders for the transdisciplinary character of the transgenerational problem at hand.
Strategy of Management of the Radioactive Waste for an Emerging Country and International Co-Operation: Example of Tunisia
Authors: Chalbi Mourad , Ghedira Lotfi , Allal Samir
Published: April 2020

It is a striking and happy reality today at the same time, marked universally: What it is agreed to call the nuclear controversy is remained circumscribed with nuclear energy and rather confined with the industrialized countries. The other economic and social applications of the nuclear techniques experience a very important development all over the world and which has to continue. The countries of intermediate socio-economic level do not escape this report. And even if these countries have, generally, slightly resorted to nuclear energy, the World Energy Conference (the USA, 1999) provides that nuclear energy will know in the court - medium term a rise in the emerging countries which will come to compensate for its relative retreat in the industrialized countries.

There is consequently a number unceasingly crescent of “small producers” of radioactive waste particularly in the emerging countries but, unfortunately, this waste is not dealt with in a rigorous and exhaustive way, generating a potential serious threat engraves for the people and the environment. The analysis of this situation, from the case of Tunisia, reveals the following cause: miss of infrastructures, qualified personnel, financial means and impossibility of coping with these difficulties without international co-operation there. In this communication we propose a strategy, on a 20 years horizon of management of the radioactive waste for Tunisia taking account of the means of the country and the essential contribution of the co-operation. We make share in this respect already committed experiment of the three-way co-operation Tunisia - IAEA - Belgium.

The strategy that we propose articulates on the following points:

1. Definition of the long-term objectives and the principles;

2. The institutional and regular project;

3. The inventory of the radioactive waste;

4. The planning of the formation;

5. The project of a pilot unit for waste processing and storage;

6. The question of the evacuation;

The above actions are evoked in interference with the role of the international co-operation.
Pollutant Release Level Prognosis: A Major Input Into the Flooding Concept for the Former ISL Uranium Mine at Königstein (Germany)
Authors: Jenk Ulf , Schreyer Jochen
Published: April 2020

At the Königstein mine uranium was extracted by an underground in situ leaching method. WISMUT developed a flooding concept which allows the reduction of pollutant concentrations and prevent pollutant migration into the aquifers above and downstream the mine. The development of the concept and the documentation for permit application were based on a multitude of scientific and engineering studies and prognoses on substance output using two different approaches (upscaling of a flooding experiment, Numeric box model). Both modelling tools provide similar prognoses of flooding. With the flooding in progress (start January 2001), the modelling tools will be validated and further improved.
Derivation of Clearance Levels for the New German Radiation Protection Ordinance
Authors: Thierfeldt Stefan , Kugeler Ernst , Nüsser Alexander , Sefzig Renate , Landfermann Hans-Henning , Weimer Günter
Published: April 2020

The new Radiation Protection Ordinance (RPO) in Germany which transforms the EURATOM Basic Safety Standards into national legislation contains detailed regulations on clearance. For each of the following clearance options, a separate set of clearance levels (CL) exists: unconditional clearance, clearance of building rubble (> 1000 Mg/a), clearance of buildings for demolition and for reuse, clearance of nuclear sites, and clearance for disposal or incineration. This paper outlines the basis for the derivation of these sets of CL which are all based on generic radiological scenarios taking into account all relevant aspects of the materials. The underlying dose criterion is 10 μSv/a individual dose and 1 man·Sv/a collective dose.

When deriving sets of CL in Germany care has been taken to be compatible with recommendations of the European Union and the IAEA. It is a common experience that sets of CL which are intended for the same purpose (e.g. general, unconditional clearance) may vary between studies and therefore between countries. This follows directly from differences e.g. in material quantities, boundary conditions, waste management options etc. which may be country specific. German CL are, however, in full agreement with all recommendations issued by the European Commission.
The Disposition of Civil Plutonium in the UK
Authors: Barker Fred , Sadnicki Mike
Published: April 2020

This paper presents the findings of research on potential strategies for the management of separated plutonium in the UK*. These strategies include the use of plutonium as a reactor fuel (MOX), or immobilising it as a waste. The paper reviews the hurdles to MOX fuel use in the UK. These include the need for large-scale subsidy for building new reactors. Estimates for the scale of the subsidy are presented. It also reviews the hurdles to immobilising plutonium using a ‘can-in-canister’ approach with vitrified High Level Waste (HLW), as originally proposed in the US. The paper discusses the requirements of alternative immobilization strategies. It identifies a range of options and presents cost estimates. The paper addresses the question of what would constitute a cost-effective approach to immobilization in a UK context.
Disposing of Excess Weapons Materials: Past and Future of Belgian Plutonium Technology
Authors: Vanderborck Yvon , Basselier Jacques
Published: April 2020

Long term storage of plutonium separated from fission products is not a good solution according to the current non-proliferation criteria as well as from an economic point of view. This material has thus to be converted to the equivalent of the “spent fuel standard”. Only one technique has so far reached the industrial maturity necessary to convert the important existing plutonium stockpiles: it is the use of plutonium to manufacture and irradiate MOX fuel. The paper reviews the existing information over the separated plutonium stockpiles and the various International Agreements, which are implemented to cover the peaceful use of plutonium.

The dual track solution retained in U.S. in mentioned. The situation U.S. and Russia is updated, the roles of Europe and Belgium are presented.

The activities of BELGONUCLEAIRE on the US and Russian sides will be described and its experience in fabrication technology, quality, safety, environmental issues, non-proliferation, safeguards and transport will be considered. The transfer of technology to France, Japan and US makes the MIMAS BELGONUCLEAIRE fabrication process equivalent to an international standard. This forms a sound basis for further development and for a transfer to Russia. The paper will demonstrate by this way the commitment of BELGONUCLEAIRE to participate to the peaceful uses of plutonium, as well as its contribution safely to non-proliferation and disarmament international policy.
Effect of Canister Filling by Multiple Pouring Batches on Quality Properties of HLW Glass Product
Authors: Roth G. , Weisenburger S. , Grünewald W. , Gauthier Y.
Published: April 2020

About 70 m3 of highly active liquid waste generated by the former German WAK (Wiederaufarbeitungsanlage Karlsruhe) reprocessing plant will be conditioned in a new vitrification facility of Forschungszentrum Karlsruhe (FZK). The use of s small-scale liquid-fed ceramic melter necessitates the filling of the glass canisters by four separate pourings. The effect of the multiple batches on relevant properties of the glass product was investigated within the operation of an inactive prototype test facility. The paper describes results from the investigation of glass samples taken from the interfaces between the batches from a cut canister and from non-destructive canister examination using computer tomography.
Remote Dismantling of the WWER Reactors in Greifswald
Authors: Raasch Jürgen , Borchardt Ralf
Published: April 2020

At the Greifswald site, there are 8 units of the Russian pressurised water reactor type WWER 440. After the reunification of Germany, it was decided to decommission all units without a safe enclosure phase.

Due to the high activation of the components of the reactors 1 to 4, it was necessary to use mainly remote dismantling techniques. The concept first foresees a model dismantling in the steam generator room of unit 5 to test the transport, cutting and packaging equipment to perform the later dismantling of the activated reactors 1 to 4 safely and optimally. For this purpose the non-activated and non-contaminated equipment of the units 7 and 8 will be used. For the dismantling, a dry cutting area, wet cutting area and a cutting area in the reactor cavity room are foreseen.

The installations of the cutting equipment in the steam generator room of unit 5 were executed from June 1997 until September 1999.

During model dismantling, several technical problems occurred, especially with the band saws and video technique, which strongly affected or even stopped the tests. For these reasons, only few data are available for the evaluation of the cutting procedures and for the estimation of the time needed as well as for the radiological exposure to be expected for units 1 to 4.
Kinetic Study of the Crystallized ThO2 and Solid Solutions Th1−xUxO2 Dissolution
Authors: Heisbourg G. , Dacheux N. , Lagarde G. , Hubert S. , Ritt J.
Published: April 2020

Thorium dioxide is an important material for the nuclear industry. In the last decade, there has been a renewal of interest in studying the feasibility of thorium based fuel reactor to decrease the minor actinides production during the burn-up. Furthermore the resistance of the thorium dioxide to aqueous corrosion can make this material attractive for immobilizing tetravalent actinides. Leaching tests of powdered samples of thorium dioxide calcinated at 1300°C showed that the normalized dissolution rate is very low (between 10−6 and 10−7 g/(m2.d) in acidic media, and 10−9–10−10 g/(m2.d) after pH>3 when the formation of colloïdes occurs. Thorium dioxide which is isomorphic with the actinide dioxides such as UO2, PuO2 allows the formation of solid solutions whatever the concentration of the actinide. Several solid solutions Th1−xUxO2 were synthesized with mole-ratios Th/(U+Th) ranging from x = 0 to 1. X-ray powder diffraction data allowed to check that the Vegard’s law is respected in all the range, and specific surface area was also measured. The resistance of the solid-solution to aqueous corrosion was measured as a function of several parameters (leaching time, leachate acidity, uranium concentration) and the kinetics of solid solutions dissolution was determined as a function of the uranium concentration. The stoechiometry of the release of both actinides was verified, however due to the oxidization of U (IV) in U (VI) in contact with the leachate, the dissolution rate of both thorium and uranium increases with the thorium substitution in the solid by uranium (TV).
Manufacturing and Handling Techniques of the Monolithic Buffer Material for HLW Disposal
Authors: Awano Toshihiko , Kanno Takeshi , Kawakami Susumu , Ueda Hiroyoshi , Kimoto Takahiro
Published: April 2020

Small and large scale tests were performed to evaluate technical feasibility of the monolithic buffer material, defined as a large block of bentonite formed by the cold isostatic pressing, for geological disposal of high-level radioactive waste. Trial manufacturing tests up to approximately 70 [%]-scale of a Japanese disposal concept were carried out and emplacement tests were carried out by vacuum lifting and forklift-type methods for vertical and horizontal emplacement concepts, respectively. Based on the large engineering-scale tests, technical feasibility of the monolithic buffer was demonstrated.
Thorough Chemical Decontamination MEDOC®: An Effective Way to Reduce Metallic Waste Volume of the Dismantled Materials
Authors: Ponnet Mathieu , Klein Michel , Rahier André , Noynaert Luc , Aleton Gérard
Published: April 2020

The dismantling of the BR3-PWR reactor leads to the production of large masses of contaminated metallic pieces, including structural materials, primary pipings, tanks and heat exchangers. One of the main objectives is to demonstrate that we can minimise the volume of radioactive waste in an economical way, by the use of alternative waste routes, such as recycling of material in the nuclear world, free release of material in the conventional industry after melting or free release of material after thorough decontamination. The SCK•CEN launched a decontamination program with the aim to free release as much of the dismantled metallic material as possible.

The selected chemical decontamination process, so-called MEDOC® (MEtal Decontamination by Oxidation with Cerium), is based on the use of cerium IV as strong oxidant in sulphuric acid with continuous regeneration using ozone. An industrial installation has been designed and constructed in close collaboration with Framatome-France. This installation started to operate in September 1999 for the treatment of the metallic pieces arising from the dismantling of the BR3 reactor. Since the installation starts up, 21 tons of contaminated material has been treated batchwise with success.

Up to now, MEDOC® has been accomplished as a batch process in which the decontamination reactor is loaded with a basket containing the contaminated material. The SCK•CEN is now considering the possibility of using the MEDOC plant to decontaminate large components before cutting them, such as the BR3 -steam generator and the pressurizer. The decontamination solution will be circulated between the MEDOC plant and the steam generator during the consecutive decontamination cycles. Each cycle will comprises a decontamination step followed by a regeneration step. For the steam generator, 30 cycles are estimated to be needed to reach the free release level after melting. The decontamination studies of large components are ongoing and take into account the technical aspects, the radiological and classical safety aspects, as well as financial aspects.
CORA Project: Vitrification of Intermediate Level Liquid Radioactive Wastes in Saluggia ENEA Research Centre
Authors: Calle Carlos A. , Luce Alfredo
Published: April 2020

The EUREX reprocessing pilot plant, at ENEA Research Centre, Saluggia (VC - Italy), stores 113 m3 of intermediate level liquid waste and 110 m3 of low level liquid waste, originating from the past reprocessing campaigns.

Conditioning of the above wastes, for the purpose of final disposal, has been planned in a new installation for the solidification of both intermediate and low level wastes at Saluggia site. The installation, under design, has been named CORA Plant (COnditioning of RAdioactive wastes).

Direct Vitrification process using cold crucible melter (CCM) developed by CEA of Marcoule, has been chosen as conditioning technology for a mix of most active wastes and cementation for secondary low level waste produced during vitrification.

A boro-silicate glass matrix has been selected with a specific nominal chemical composition adapted to liquid waste matrix. Characterisation work of this specific glass is under progress.

CORA has been presented to regulatory authority has a modification of a pilot reprocessing Eurex plant.

Vitrification equipment and glass canister interim storage facility of CORA Plant will be housed inside the existing building of Eurex facility properly modified. Cementation unit inside a new building located in a near external yard.

A description of the waste management scheme, as well as a brief description of adopted technologies, chemical glass composition and updated schedule of CORA project is presented in this paper.
Canister Sealing for High Level Waste Encapsulation
Authors: Andrews Richard E.
Published: April 2020

Sweden has chosen to manage spent fuel rods by direct encapsulation and storage in a deep level repository. Two welding processes are being investigated for the sealing of copper vessels that form the outer barrier of the disposal canisters.

TWI Ltd in the UK has developed Reduced Pressure Electron Beam Welding and Friction Stir Welding for 50mm thick copper. This paper describes some of the investigations and compares the techniques. Over the past 3 years a full-size canister welding machine has been designed and built. Specialised tools have been developed for the welding of thick sections in copper with very encouraging results.
Uncertainties in photoemission peak fitting accounting for the covariance with background parameters
Authors: Herrera-Gomez Alberto
Published: April 2020

The uncertainties for peak parameters obtained through peak-fitting x-ray photoelectron spectroscopy data are assessed using a rigorous covariance matrix approach. By incorporating the Active Approach, the method accounts for the covariance of the peak parameters with the rest of the parameters including those defining the background signal. Peak intensities (i.e., the areas) are employed as direct fitting parameters, so their uncertainties are directly determined. The method was tested employing a series of synthetic datasets. The results revealed a remarkable agreement between the standard deviations of the fitting parameters calculated through the proposed method and from the fitting results of the synthetic data.
Epitaxial to axiotaxial texture evolution in endotaxial MnP films grown on GaP (100)
Authors: Nateghi Nima , Lambert-Milot Samuel , Masut Remo A.
Published: April 2020

Epitaxial to axiotaxial texture transition as a function of substrate temperature is reported in polycrystalline MnP films, which were grown on GaP (100) substrates using metal organic vapor phase epitaxy. At low growth temperatures, the texture consists of a limited number of epitaxial orientations, which have a common alignment (axiotaxy axis). The number of epitaxial orientations increases at higher growth temperatures, while keeping the same axiotaxy axes, such that only axiotaxial texture is observed at growth temperatures above 700 °C. An estimate of the strain values on the axiotaxy axes at the MnP/GaP interface is provided, assuming a periodic interface, which would favor strain minimization as the main reason for the preservation of such a texture. Since MnP grains grow endotaxially on GaP, this texture transition may be a consequence of MnP/GaP interface reconstruction at different growth temperatures.
Energy transfer within the hydrogen bonding network of water following resonant terahertz excitation
Authors: Elgabarty Hossam , Kampfrath Tobias , Bonthuis Douwe Jan , Balos Vasileios , Kaliannan Naveen Kumar , Loche Philip , Netz Roland R. , Wolf Martin , Kühne Thomas D. , Sajadi Mohsen
Published: April 2020

Energy flow in the hydrogen bonding network of water is traced by resonant terahertz excitation and off-resonant optical probing.
A new solvent system: Hydrothermal molten salt
Authors: Voisin T. , Erriguible A. , Aymonier C.
Published: April 2020

NaOH injected in supercritical water forms a molten salt phase, offering advances in flow chemistry.
Realizing small-flake graphene oxide membranes for ultrafast size-dependent organic solvent nanofiltration
Authors: Nie Lina , Goh Kunli , Wang Yu , Lee Jaewoo , Huang Yinjuan , Karahan H. Enis , Zhou Kun , Guiver Michael D. , Bae Tae-Hyun
Published: April 2020

La
3+
cross-linking produces robust membranes from small-flake graphene oxide, which induces fast organic solvent permeances.
Minimal quantum viscosity from fundamental physical constants
Authors: Trachenko K. , Brazhkin V. V.
Published: April 2020

We find a fundamental lower limit of liquid viscosity, setting how runny a liquid can ever get.
The Impact of a Semester-Long, Cell Culture and Fluorescence Microscopy CURE on Learning and Attitudes in an Underrepresented STEM Student Population
Authors: Hurst-Kennedy Jennifer , Saum Michael , Achat-Mendes Cindy , D’Costa Allison , Javazon Elisabeth , Katzman Shoshana , Ricks Ernest , Barrera Alessandra
Published: April 2020

Georgia Gwinnett College (GGC) is an access institution with a diverse student body, located in metro Atlanta. To strengthen research skills, teach employer-valued cell biology laboratory techniques, and increase student engagement, a semester-long, inquiry-based CURE was developed and implemented in Cell Biology with Laboratory (BIOL3400K), a sophomore-level course, which serves as a “gateway” to all upper-level biology courses. This CURE centers on the investigation of a student-chosen experimental factor on the viability of cultured, mammalian cells. Through participation in this CURE, students gain experience in cell culture, fluorescence microscopy, and viability assays, and strengthen important research skills, such as literature searches, graphing, and data analyses. The impact of this CURE on student learning gains and attitudes was assessed using pre-/post-content exams and the Colorado Learning Attitudes about Science Survey (CLASS). Our data show that all students made significant content gains. Female students made larger learning gains than male students. Additionally, minority students performed better than majority students in some content areas. Student attitudes did not change, or in some cases were slightly more negative after the CURE. Overall, this CURE had a positive impact on students by engaging them in an inquiry-based laboratory experience.
Nuclear Ssr4 Is Required for the
In Vitro
and
In Vivo
Asexual Cycles and Global Gene Activity of Beauveria bassiana
Authors: Shao Wei , Cai Qing , Tong Sen-Miao , Ying Sheng-Hua , Feng Ming-Guang
Published: April 2020

Ssr4 is known to serve as a cosubunit of chromatin-remodeling SWI/SNF and RSC complexes in yeasts but has not been functionally characterized in fungi. This study unveils for the first time the pleiotropic effects caused by deletion of
ssr4
and its role in mediating global gene expression in a fungal insect pathogen. Our findings confirm an essential role of Ssr4 in hydrophobin biosynthesis and assembly required for growth, differentiation, and development of aerial hyphae for conidiation and conidial adhesion to insect surface and its essentiality for insect pathogenicity and virulence-related cellular events. Importantly, Ssr4 can regulate nearly one-fourth of all genes in the fungal genome in direct and indirect manners, including dozens involved in gene activity and hundreds involved in metabolism and/or transport of carbohydrates, amino acids, lipids, and/or inorganic ions. These findings highlight a significance of Ssr4 for filamentous fungal lifestyle.
Successful sparing approach between the ascending aorta and the main pulmonary artery to the giant coronary aneurysm of the left main coronary artery
Authors: Nakamura Ken , Orii Kouan , Abe Takayuki , Haida Hirofumi
Published: April 2020

Coronary aneurysm located just above the left main coronary artery (LMT) is rare and difficult to treat. How the aneurysm is accessed is very important as it determines the result of the surgery. A 70-year-old man with a large coronary aneurysm (40 mm in diameter) in the LMT underwent surgery to prevent its rupture; however, there was severe adhesion. Initially, dissection of the ascending aorta or the pulmonary artery seemed necessary to access the aneurysm; however, the process was possible with limited dissection between the ascending aorta and the pulmonary artery, and we succeeded in firmly closing the LMT site of entry.
Clinical and neuropsychological profile of patients with dementia and chronic traumatic encephalopathy
Authors: LoBue Christian , Schaffert Jeff , Cullum C Munro , Peters Matthew E , Didehbani Nyaz , Hart John , White Charles L
Published: April 2020

Objective

To determine whether subjects with chronic traumatic encephalopathy (CTE) and dementia have distinct clinical features compared to subjects with pathologically confirmed Alzheimer’s disease (AD).

Methods

Among 339 subjects assessed for CTE in the National Alzheimer’s Coordinating Center dataset, 6 subjects with CTE and 25 subjects with AD neuropathologic change matched for age (±5 years) and sex were identified. All subjects had a clinical diagnosis of dementia. Neurological examination, neuropsychological testing and emotional/behavioural data were compared between CTE and AD subjects at the time of dementia diagnosis and last clinical visit near death.

Results

A history of traumatic brain injury with loss of consciousness (LOC) was reported in one CTE and one AD subject; information about injuries without LOC or multiple injuries was unavailable. CTE and AD subjects did not differ significantly at the time of diagnosis or last visit on the Unified Parkinson’s Disease Rating Scale—Motor Exam, global measures of cognitive functioning (Mini-Mental State Exam and Clinical Dementia Rating Scale), emotional/behaviour symptoms as assessed with the Neuropsychiatric Inventory questionnaire or across neuropsychological measures. All CTE participants had co-occurring neuropathologic processes, including AD and most had TAR DNA-binding protein 43 (TDP-43) neuropathology.

Conclusions

CTE pathology was rare in a large multicentre national dataset, and when present, was accompanied by AD and TDP-43 pathologies. CTE was not associated with a different clinical presentation from AD or with greater cognitive impairment or neurobehavioral symptoms. These findings suggest that CTE may not have a distinct clinical profile when other neuropathologic processes are coexistent with CTE pathology.
Meaningful futility: requests for resuscitation against medical recommendation
Authors: Vivas Lucas , Carpenter Travis
Published: April 2020

‘Futility’ is a contentious term that has eluded clear definition, with proposed descriptions either too strict or too vague to encompass the many facets of medical care. Requests for futile care are often surrogates for requests of a more existential character, covering the whole range of personal, emotional, cultural and spiritual needs. Physicians and other practitioners can use requests for futile care as a valuable opportunity to connect with their patients at a deeper level than the mere biomedical diagnosis. Current debate around Canada’s changing regulatory and legal framework highlights challenges in appropriately balancing the benefits and burdens created by requests for futile care.
Elevation of inflammatory S100A8/S100A9 complexes in intracranial aneurysms
Authors: de Korte Antonius Mattheus , Aquarius René , Vogl Thomas , Roth Johannes , Bartels Ronald H M A , Boogaarts Hieronymus D , van Lent Peter L E M , De Vries Joost
Published: April 2020

Background

Inflammation-related factors might give further insight into the pathophysiology of vessel wall inflammation and intracranial aneurysm (IA) rupture. One of these factors is the protein complex S100A8/A9, which is released by neutrophils, monocytes, and activated macrophages and is known for its role in cardiovascular disease.

Objective

To determine if venous S100A8/A9 levels in patients with a ruptured IA (rIA) or unruptured IA (uIA) are elevated compared with a control group. Second, to assess differences between venous and intra-aneurysmal S100A8/A9 levels of rIA and uIA patients.

Methods

A prospective case study was performed between June 2016 and May 2017 in patients harboring a ruptured or unruptured saccular IA. Primary outcome measures were individual S100A8/A9 serum concentrations as measured in venous and intra-aneurysmal blood samples during endovascular treatment. Venous serum S100A8/A9 concentrations from a healthy control group served as a reference.

Results

We included 16 patients with either a rIA or uIA and 47 healthy controls. Venous S100A8/A9 concentrations were higher in aneurysm patients (rIA and uIA) than those of healthy controls (P≤0.001). S100A8/A9 concentrations were higher in intra-aneurysmal samples than in venous samples of rIA patients (P=0.011). This difference was not found in uIA patients (P=0.054). Intra-aneurysmal S100A8/A9 levels were higher in rIAs than in uIAs (P=0.04).

Conclusions

Venous S100A8/A9 levels are elevated in patients with both rIAs and uIAs compared with healthy controls and likely represents aneurysm wall inflammation. S100A8/A9 causes macrophage-induced inflammation and degeneration of the vessel wall which might explain higher intra-aneurysmal S100A8/A9 levels found in rIAs than in uIAs.
Pituitary tumour apoplexy due to pituitary adenoma in a dog: clinical, 3T MRI and CT features
Authors: Briola Chiara , Galli Greta , Menchetti Marika , Caldin Marco , Bertolini Giovanna
Published: April 2020

Pituitary apoplexy (PA) is a neurological syndrome resulting from sudden infarction/haemorrhage within a normal or tumoural pituitary gland. Prompt imaging is essential to correlate haemorrhagic/ischaemic changes with clinical signs. The purpose of this report is to describe the clinical, CT and 3T MRI findings of PA in a 13‐year‐old dog previously diagnosed with pituitary‐dependent hyperadrenocorticism. Neurological examination revealed an anxious‐compulsive behaviour, internal ophthalmoplegia and bilaterally reduced menace response. Brain MRI showed a pituitary mass with two focal well‐defined areas. The first was T2 weighted (T2w) and T1 weighted (T1w) hyperintense, FLAIR hypointense to the grey matter, and mildly contrast‐enhancing with signal void artefact in GE‐T2*, compatible with late/subacute haemorrhage; the second was T2w hypointense, T1w, FLAIR and GE‐T2* isointense/hypointense to the grey matter and moderately enhancing, compatible with acute haemorrhage. The dog recovered after 24 hours, but internal ophthalmoplegia remained. To the authors’ knowledge, this is the first report describing MRI findings in a dog with PA.
New species in the Gymnopilus junonius group (Basidiomycota: Agaricales)
Authors: Thorn R. Greg , Malloch David W. , Saar Irja , Lamoureux Yves , Nagasawa Eiji , Redhead Scott A. , Margaritescu Simona , Moncalvo Jean-Marc
Published: April 2020

Mushrooms named Gymnopilus spectabilis and G. junonius have been reported widely in North America on both dead hardwood or dead or living conifers. Based on DNA sequences of the internal transcribed spacer region (ITS) and large ribosomal subunit (LSU), we found that although Gymnopilus junonius (= G. spectabilis s. auct.) is widespread in Europe, South America, and Australia, none of the limited sequences available from North America represent this species. We report five species of this group from North America, including three previously described species, G. luteus, G. subspectabilis, and G. ventricosus, and two new species, Gymnopilus voitkii and Gymnopilus speciosissimus. We recognize a sister species to G. luteus, based on sequences previously reported as G. spectabilis from China, Japan, and the Russian Far East, but, lacking material to describe it as a new species, we give it an informal clade name, /sororiluteus. Another new species in this complex is described from Japan, as Gymnopilus orientispectabilis. Species in this group may be distinguished by their ITS sequences as well as by macro- and micromorphology, substrate, and geography.