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[en] This new edition of the Nuclear Law Bulletin Index covers the first 103 issues of the Nuclear Law Bulletin (NLB). By established practice, the plan of the Index is not a replica of the Bulletin, as it was considered more useful for research purposes to group together all the information concerning legislative and regulatory activities, case law and bilateral agreements and to classify this information by country. Following classification by country, references to the work of international organisations, multilateral agreements, studies and articles are set out in separate sections. The 'Bibliography and News Briefs' section is omitted from the Index. A separate chapter of the Index has been devoted to the listing of the instruments published in the Supplements to the Bulletin, or in the Chapter 'Texts' from past Bulletins, up until the present date. Each item in the Index is followed by a reference to the relevant Bulletin. Legislative and regulatory texts, as well as agreements reproduced in the Bulletins or their Supplements, are also referenced
[en] This paper presents a conceptual design for a plant-wide autonomous operation system that uses artificial intelligence techniques. The autonomous operation system has the power and ability to perform the control functions needed for the emergency operation of a nuclear power plant (NPP) with reduced operator intervention. This paper discusses the emergency operation and level of automation in an NPP and presents the design requirements for an autonomous emergency operation system (A-EOS). Then, an architecture that consists of several modules is proposed, with descriptions of the functions. Finally, this paper introduces a prototype of the suggested autonomous system that integrates the authors’ previous works
[en] During transients or accidents, the reactor core is uncovered, and droplets entrained above the quench front collides with the uncovered fuel rod surface. Droplet impact cooling can reduce the peak cladding temperature. Besides zirconium-based cladding, versatile accidental tolerant fuel (ATF) claddings, including FeCrAl, have been proposed to increase the accident coping time. In order to investigate the effect of surface properties on droplet impact cooling of cladding surfaces, the droplet impact phenomena are photographed on the FeCrAl and zircaloy-4 (Zr-4) surfaces under different conditions. On the oxidized FeCrAl surface, the Leidenfrost phenomenon is not observed even when the surface temperature is as high as 550 °C with We > 30. Comparison of the impact behaviors observed on different materials shows that nucleate and transition boiling is more intensive on surfaces with larger thermal conductivity. The Leidenfrost point temperature (LPT) decreases with the solid thermal effusivity (kρCp). However, the CHF temperature is relatively insensitive to the surface oxidation and Weber number. Droplet spreading diameter is analyzed quantitatively in the film boiling stage. Based on the energy balance a correlation is proposed for droplet maximum spreading factor. A mechanistic model is also developed for the LPT based on homogeneous nucleation theory.
[en] Super fine-grained graphite is a type of advanced nuclear graphite which was developed for Molten Salt Reactor (MSR). It is necessary to establish a failure assessment method used for nuclear graphite components in MSR. A modified assessment approach based on ASME BPVC-III-52017 is presented. The new approach takes a new parameter, KIC, into account and abandons the parameter, grain size, which is unrealistic for super fine-grained graphite as the computation is enormous if we use conventional methods. Three methodologies (KTA 3232, ASME, New approach) were also evaluated by theoretical prediction and experimental verification. The results indicated the new developed code can be used for design and failure assessment of super fine-graphite components and has more extensive applicability.
[en] Investigations of the commercial aircraft impact effect on nuclear island infrastructures have been drawing extensive attention, and this paper aims to perform the safety assessment of Generation Ⅲ nuclear power plant (NPP) buildings subjected to typical commercial aircrafts crash. At present Part I, finite element (FE) models establishment and validations for both the aircrafts and NPP buildings are performed. (i) Airbus A320 and A380 aircrafts are selected as the representative medium and large commercial aircrafts, and the corresponding fine FE models including the skin, beam, fuel and etc. are established. By comparing the numerically derived impact force time-histories with the existing published literatures, the rationality of aircrafts models is verified. (ii) Fine FE model of the Chinese Zhejiang Sanao NPP buildings is established, including the detailed structures and reinforcing arrangement of both the containment and auxiliary buildings. (iii) By numerically reproducing the existing 1/7.5 scaled aircraft model impact tests on steel plate reinforced concrete (SC) panels and assessing the impact process and velocity time-history of aircraft model, as well as the damage and the maximum deflection of SC panels, the applicability of the existing three concrete constitutive models (i.e., K&C, Winfrith and CSC) are evaluated and the superiority of Winfrith model for SC panels under deformable missile impact is verified. The present work can provide beneficial reference for the integral aircraft crash analyses and structural damage assessment in the following two parts of this paper.
[en] This comprehensive document issued by the Swiss Nuclear Safety Inspectorate ENSI in October 2020 reports on its activities in accordance with Article 32 of the Joint Convention on the Safety of Spent Fuel and Radioactive Waste Management. The report is composed of ten Sections. An introduction presents basic information and an overview. Further sections cover aspects such as polices and practices, scope of application, inventories and lists, legislative and regulatory system, general safety provisions, safety of spent fuel management, safety of radioactive waste management, transboundary movement and disused sealed sources. Finally, general efforts to improve safety are discussed. Two Annexes complete the report.
[en] The use of ionizing radiation in Africa is more than a century old but the awareness for radiation safety regulation is still work in progress. The nuclear weapon tests carried out in the Sahara Desert during the early 1960’s and the resultant radiation fallout that drifted into West Africa with the north-easterly winds provided the first organized response to the hazards of ionizing radiation in Nigeria. The Nigerian Government in 1964 established the Federal Radiation Protection Service (FRPS) at the Physics Department of the University of Ibadan but without the force of law. In 1971, draft legislation on Nuclear Safety and Radiation Protection was submitted to Government for consideration and promulgation. It never went beyond a draft until June 1995 only after IAEA intervention! The April 1986 Chernobyl nuclear accident unfortunately did not provoke as much reaction from African countries, probably because of geography and climate: Africa is far from Ukraine and in April the winds blow from SW-NE, unlike if it had happened in December when the wind direction would have been NE-SW and Africa would have been greatly impacted with little or no radiation safety infrastructure to detect the radiation fallout or to respond to it; and weak economic infrastructure to mitigate the economic impact of such radioactive deposits on agriculture and human health. Africa was shielded by both geography and climate; but not for long. By 1988, some unscrupulous businessmen exported to Nigeria and to several African countries radiation contaminated beef and dairy products which were meant for destruction in Europe. This led to the establishment of laboratories in several African countries for the monitoring of radiation contamination of imported foods. Fortunately, the international response to the Chernobyl accident was swift and beneficial to Africa and largely spurred the establishment of radiation safety infrastructure in most if not all African Member States. Notably amongst the IAEA interventions towards the establishment of radiation safety infrastructure are the RAPAT missions and the Model Project on “Strengthening Radiation Protection Infrastructure”. The Model Project (1994-2004) aimed at assisting Member States in meeting the requirements of the international basic safety standards. The Model Project achieved a lot but its closure in 2004 compelled regulatory bodies in the Africa to search for alternative mechanism for building on the success of the Model Project and find ways and means of expanding the scope of the Model Project but without the sole sponsorship of or promotion by the Agency by taking ownership of radiation safety infrastructure in their countries. This resolution led to several discussions and consultations among regulatory bodies in the region which culminated in 2009 into the formation of the Forum of Nuclear Regulatory Authorities in Africa. The IAEA RASSIA Missions and the IRRS Missions provide the opportunity to peer-review the radiation safety infrastructure and promote continuous improvement. The ultimate goal of all these efforts is the emplacement of a sustainable radiation safety culture, which is a fabric that can be woven with different fibres: legislation, institutions, manpower, national and international support, etc. Development of radiation safety infrastructure in Africa and indeed the evolution of the radiation safety culture in the region is indeed work in progress. (author)
[en] The tool presented in the paper is recommended to support regulatory oversight of the safety culture in German nuclear power plants taking into account the particular challenges of the post-Fukushima decision to phase out civil nuclear energy production. The tool is based on empirical research findings on how observable actions and measures of leadership (e.g. clear instructions regarding the priority of safety) influence directly unobservable psychological drivers of human action (e.g. personnel’s motivation to act safely) and personnel’s observable safe performance which depends on these drivers. These empirical research findings thus capture how this kind of observable leadership activities will foster unobservable and observable aspects of safety culture and safety-directed human action. The tool supports inspectors’ collection, processing, and evaluation of information about this kind of observable leadership activities at the licensee’s. In total, 17 activities are considered which cover the entire range of leadership. The evaluation of collected information with the tool shows to which extent leadership fosters safety culture in the licensee organization and its members and, consequently, to which extent the safety culture of the licensee is a strong one. The tool is designed in such a way that it supports information collection during any kind of inspection on site and by inspectors after the familiarization which is necessary in order to use the tool (“en-passant approach”). Since many inspections are carried out in the course of time, the en-passant tool application can provide regulatory authorities with a steady flow of up-to date information which can comprise early indications of degradations in the area of safety culture. The tool does also support in-depth investigations and evaluations of licensee’s safety culture by inspector teams which comprise experts in the area of safety culture. For both enpassant approach and in-depth analyses, the tool provides proper guidance. (author)
[en] This work presents the characterization of the thermal and rheological behavior of a new composite materials based on a Diglycidyl Ether of Bisphenol A (DGEBA) epoxy resin reinforced with Triglycidyl-2-Aminothiophenol (TGATP). The hardener used refers to 4,4’-Methylene Dianiline (MDA). DGEBA-TGATP-MDA epoxy composite materials of TGATP content varying between 5 wt. % and 15 wt. % are prepared via melt compounding. The differential scanning calorimetry results show that the presence of TGATP can remarkably improve the material thermal properties. The rheological investigation results show that TGATP amount and dispersion are responsible for the composite increased thermal stability. Keywords: composite materials, DGEBA, TGATP, thermal and rheological properties.
[en] The research work aims to quantify the concentration of nicotine and the toxic elements identified after different toombak fermentation procedures and secondly to evaluate their possible association with oral cancer. High performance liquid chromatography was used to measure nicotine, while inductive coupled plasma- emission spectroscopy was used to measure the concentration of the elements in off-the-shelf toombak samples, which were collected from different regions of Sudan, also raw Toombak samples fermented in the laboratory using different concentration of naturon were detected. The results showed that there is a strong correlation between the concentration of naturon used in the fermentation process and the concentration of nicotine and the toxic elements. Higher naturon concentration decreases the levels of nicotine and cd, Pb, Cr, Ni, Cu, Zn, co nevertheless the levels still exceed the recommended limits. The results can be used to control the toxicity level by standardizing the fermentation method. When the prepared naturon concentration was So ml/gram the total nicotine content was 6 ppm compared with the lowest concentration of prepared naturon 10 ml/gram the total nicotine was 46 ppm, while the total nicotine content was 206 ppm measured for toombak added naturon. The result of the study showed that nicotine content and toxic elements measured in toombak ready to use in Sudanese markets lead to hazard diseases which occurred due to addiction of the habit especially oral cancer, data were collected and analyzed using statistical method. To minimize the rich of this habit to words oral cancer and other advisers effect, it is recommended from this study to use a mixture of naturon and tobacco 3:1 respectively, and this can be regarded as standard ratio for the Sudanese standard metrology. (Author)