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Prehistoric rock art sites are endangered despite conservation efforts. The lack of scientific documentation regarding weathering agents affecting rock art and the absence of specific diagnostic protocols hinder the development of conservation strategies. The aim of this research was to investigate active deterioration processes in a granite petroglyph site located in Mougás (Galicia, NW Spain) by characterizing the granite, conducting a geotechnical study of the outcrop and describing and analysing the main weathering processes. Two main deterioration factors were identified. First, water favours block disjunction at the massif scale and causes pitting and surface erosion at the millimetre scale that affects the readability of the engravings. Second, high temperatures associated with wildfires cause mineral transformations that increase the susceptibility of the rock to weathering. Identifying deterioration factors is a first step in developing appropriate preventive conservation measures, which should aim to reduce rock contact time with water (technically affordable in the short term) and to reduce the probability of wildfire occurrence (technically more complex and possibly with longer‐term results). Copyright © 2018 John Wiley & Sons, Ltd.

Westinghouse is evaluating several advanced zirconium-based alloys, designated collectively as AXIOM™, to achieve improved performance for more demanding fuel management schemes. There are five candidate AXIOM alloys currently being evaluated by Westinghouse. The in–pressurized water reactor (PWR) performance of one candidate alloy, X5A, is reviewed in this paper. The irradiation performance of X5A (previously identified as Alloy A) cladding that was fabricated using high-temperature processing (HTP) was published in 2002. Since then, the fabrication process of X5A was optimized by the use of a low-temperature process (LTP). Cladding tubes with the improved processing have been irradiated in two commercial PWRs (PWR A and PWR B) and in two test reactors (Test Reactor C and Test Reactor D). The irradiation performance of both versions (HTP X5A and LTP X5A) is reviewed in this paper with a primary emphasis on the current LTP cladding. After achieving an intermediate burnup in the range of 48–54 GWd/Metric Ton of Uranium (MTU) in PWR A, the average maximum oxide layer thickness for LTP X5A was about 23 μm or about 27 % lower than the oxide thickness on ZIRLO® clad fuel rods. In addition, the fuel rod axial growth strain for LTP X5A was about 50 % of ZIRLO rod growth. Lead fuel rod irradiation of LTP X5A in PWR B with burnup in the range of 47–53 GWd/MTU showed about 30 % lower corrosion relative to ZIRLO rods and a 7 % lower axial rod growth strain than ZIRLO. An irradiation experiment in Test Reactor C was designed to study breakaway irradiation growth (in the absence of waterside oxidation) of several alloys. LTP X5A cladding showed a growth strain of about 20 % that of ZIRLO cladding at a fluence of 16×1025n/m2. In Test Reactor D, at a burnup of about 44 GWd/MTU, HTP X5A had the same oxide thickness as ZIRLO. However, the post-irradiation hydrogen pick-up was 35 % lower for HTP X5A compared to ZIRLO. In addition to the irradiation experience, the supplemental out-reactor autoclave evaluation of X5A welds indicates adequate weld corrosion resistance. While additional in-PWR exposures are required along with post-irradiation examination, the results to date demonstrate that X5A is a promising alloy for future PWR application.

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Firstly, a background of past studies on Roman amphorae sealing systems is presented. However, apart from the consensus regarding the use of vegetable resins, some questions remain unanswered. On this study the use of resins as sealing material is detected, as well as other components which are added to resins and remarkably improve the features of the mixture, whose essential requirement was to provide effective sealing for the ceramic container. The identification of calcic soaps on the inner part of amphorae reveals the addition of oil and lime on the sealing mix. RI~SUMI~