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Innovative reactor concepts are being studied by several research institutions and private entities for their role against climate change and energy poverty. The Generation IV International Forum, committed for more than 20 years in support of advanced reactors, has drawn up a series of objectives for the new class of nuclear plants, among which is an improvement in safety and economy through passive safety systems for the removal of decay heat. One of the most studied technologies is the lead fast reactor (LFR), whose coolant has a high boiling point, excellent shielding capabilities, and good heat transfer in forced and natural circulation, as well as neutron properties suitable for a hard spectrum. These allow for designing systems with high simplification and wide safety margins. On the other hand, opacity, corrosion, and innovative design choices require demonstration of the technology in experimental campaigns before using it in the industrial field. In recent years, Westinghouse Electric Company has begun the conceptual study of an intermediate size LFR [~460 MW(electric)] which, by exploiting the opportunities of the technology, aims at marketability over the next decade. One of the features is a passive heat removal system that allows, through different heat exchange mechanisms including conduction, convection, and radiation, for the transfer of decay heat from the reactor block to a pool of water inside the containment. The system is designed for indefinite heat removal thanks to channels that allow outside air to replace water following complete boiling. For the geometry of the system, the size, the materials, and the heat transfer mechanisms, an experimental activity is required to validate the prediction of the calculation codes and potentially support design optimization. The UK Department for Business, Energy & Industrial Strategy has recently subsidized the design, procurement, installation, and operation of the Passive Heat Removal Facility, an experimental facility to study the innovative safety system. This paper presents the activities of scaling, design, pretesting, and installation of that facility. [ABSTRACT FROM AUTHOR]

There has recently been growing interest in the development of innovative nuclear technologies that offer greater sustainability and cost effectiveness of electricity production. One of the most promising options is the lead fast reactor (LFR) technology. Lead stands out for its favorable neutron properties, allowing a hard neutron spectrum core as well as good shielding, heat transfer, and radioisotope retention capabilities. As lead has a boiling point in excess of 1700°C and does not react exothermically with either air or water, it also allows for the design of a low-pressure reactor block without an intermediate cooling circuit, which is used in other advanced reactor technologies for protecting against the interaction between primary and power conversion system coolants. The deployment of a new fleet of fast reactors is conditional on the control/prevention of the corrosion and erosion effects of the coolant against the structural materials, the systematic characterization of the interaction phenomena between the coolant and fuel and water, and the experimental qualification of innovative systems and components. To support LFR technology development, the UK Department for Business, Energy & Industrial Strategy has recently allocated 10 M£ to a team composed of Westinghouse Electric Company LLC, the Ansaldo Nuclear Group, the Italian National Agency for New Technologies, Energy and Sustainable Economic Development, the University of Manchester, and other organizations for the design, construction, and first operation of a network of eight test infrastructures widespread in the United Kingdom to address the LFR's highest priority research and development needs. One of the experimental rigs is the Versatile Loop Facility (VLF) currently under construction at the Ansaldo Nuclear Group's workshop in Wolverhampton, United Kingdom. The plant consists of a lead loop operable up to 650°C and equipped with a 500-kW electric fuel bundle simulator (resembling the Westinghouse LFR bundle) and a hybrid microchannel-type diffusion-bonded heat exchanger (which simulates the primary heat exchanger adopted in the Westinghouse LFR design). The heat removal is delegated to a supercritical water-cooling loop having a design pressure of 330 bar and maximum operating temperatures up to 620°C. In this paper we present the design of the VLF with specific details about its prototypical components and an insight into the construction and installation phases currently underway. [ABSTRACT FROM AUTHOR]

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AbstractThe Westinghouse lead-cooled fast reactor (LFR) is a next-generation nuclear power plant whose primary mission is to reduce front-end capital costs and generate flexible and cost-competitive electricity for global markets, while offering mission versatility and satisfying the highest safety and sustainability standards. The LFR is an economical choice for carbon-free power generation to meet the ambitious goals of reducing carbon emissions. The plant utilizes passive safety systems for high reliability and public safety.The LFR testing program aims to fill the technology gaps in the key materials, components, and systems of the LFR plant. It provides demonstrations of LFR engineering that reduce the uncertainty of the LFR design and experimental data for the verification and validation of the modeling and simulation computer codes. With the support of the LFR phenomena identification and ranking table, the phenomena important to plant safety with insufficient states of knowledge have been identified and a Westinghouse testing plan developed to address them.The United Kingdom Advanced Modular Reactor Program Phase 2 was purposed to advance the level of design maturity toward eventual regulatory approval and deployment. Westinghouse and its partners have developed eight state-of-the-art test facilities within the program. Among them, the Passive Heat Removal Facility, Versatile Lead Facility, Lead Water Interaction Facility, and the Lead Freezing Facility are thermal-hydraulic testing facilities, with the other four facilities dedicated to testing lead corrosion and material mechanical behavior in lead.The design, development, and testing of the four thermal-hydraulic facilities are presented in this paper. A variety of computer codes ranging from system-level analysis, component-level analysis, and high-resolution computational fluid dynamics analysis, are utilized to support the development of the facilities. The analyses provide operational and accidental conditions in the LFR to identify major testing conditions and inform the facility design and testing matrix. With a significant amount of experimental data being generated with these highly instrumented test facilities, the computer codes and models will be benchmarked against the experimental results to improve their validation and verification status. [ABSTRACT FROM AUTHOR]

Following a rubella epidemic in 1977; 1,133 samples of umbilical cord blood and 532 samples of maternal blood were assayed for specific anti-rubella haemoagglutino-inhibiting antibodies and IgM. Clinical follow-up failed to show either any increase in number of malformations and of IgM values in the malformed, or variations of mean weight and of the number of small-for-date infants. In none out of 1.031 newborns the virus was isolated from the pharynx, urine and faeces. The Authors conclude that the epidemic may have been caused by a poorly virulent virus and/or the mothers were possibly already immunized by previous infections.

The Authors report the results of IgM and IgA assays in blood of the umbilical cord of 1694 newborns during the period from October 1973 to July 1974 after a rubella epidemic occurred in Piedmont. 11.67% of the newborns showed a IgM value higher than 20 mg/100 ml; 0.88% gave values higher than 40 mg/100 ml. For 3.49% IgA values were higher than 3 mg/100 ml; in 0.89% cases it was higher than 6 mg/100 ml. These newborns with high levels of IgM and IgA have been observed: the Authors conclude that there is no correlation between high levels of IgM and IgA and prenatal infection.

During the outbreak of rubella in Turin in 1973, 110 newborns, whose mother's pregnancy clash with the epidemic, were studied for the elimination of rubella virus. 708 samples were in total examined, through inoculation in primary cultures of African green monkey kidney (and study of the possible interference with ECHO-virus type 11), and partially in RK 13 and SIRC continuous cell lines. No strain of rubella virus was isolated, and the Authors conclude that the virus involved was particularly benign from a teratogenetic point of view.

Blood lactate levels were determined by Lactate Analyzer 640 Kontron in 5 infants of diabetic mothers with pregestational insulin-dependent-diabetes, class B-C-D White, BPSP negative, in strict glycemic control all along the pregnancy. In the mothers blood lactate was found in a normal range after-delivery. In the absence of complications, the neonate of diabetic mother did not show blood lactate changes above the normal range. As well as in the neonate of non diabetic mother, blood lactate increases were found only in concomitance with respiratory acidosis. In the cases with favourable course, lactate values above 2 mmol/l were normalized in the first 24 hours after the birth. The semiautomatic determination of blood lactate supplies a good prognostic evaluation of the association between metabolic and respiratory acidosis in the neonate and should therefore be routinely used in centers for management of diabetic pregnancy.

A case of multiple arterial thromboses of the arm in the infant of a diabetic mother is reported. A hemocoagulative pattern of intravascular disseminated coagulation was present. Conservative thrombolytic treatment with Urokinase and Calciparin proved successful.

During the outbreak of rubella in Turin in 1977, 1,041 newborns, whose mother's pregnancy coincided with the epidemic, were studied for the elimination of rubella virus through inoculation in primary cultures of African green monkey kidney cells. Additional 10 embryos or fetuses of therapeutic abortion from women with rubella early in pregnancy were studied through cultivation of material of abortion and inoculation in monkey cells. Only one strain was isolated, from the placenta of an embryo whose mother suffered rubella in the 2nd month of pregnancy. The hypothesis is proposed of a particularly benignity, from a teratogenic point of view, of the virus involved in the outbreak.