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61.
ABSTRACTChalconatronite, Na2[Cu(CO3)]2·3H2O, is formed as a corrosion product when copper alloys are exposed to sodium carbonate solutions in the air. This also happens when metals come into contact with corroding soda glass which forms alkaline surface films in reaction with humidity from clean air. More often, substantial amounts of formaldehyde are present indoors which react to formate via the Cannizzarro reaction and accumulate over time in the films. Twenty cases of chalconatronite (including two mentioned in the literature) are reported as occurring on heritage objects with glass in contact with copper alloys: Baroque reliquaries with set glass gems, enamel on metal (sixteenth century and a modern replica of intentionally unstable composition), Christmas tree glass baubles with wires, glass buttons with metal shanks, a glass figure with a wire support, miners’ lamps, and a glass framed daguerreotype. These confirmed identifications might help conservators in investigating similar cases to shed more light on the formation conditions. 相似文献
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A sodium copper formate, first described in 2002, can also form on copper alloys with sodium originating from soda glass hydrolysis. The frequent occurrence (50% of 250 cases of glass-induced metal corrosion) is due to the presence of formaldehyde emissions in storage and its direct reaction to formate in the alkaline surface films. The compound can be produced without the presence of acetate when chalconatronite or metal coupons immersed in soda solution are exposed to formaldehyde vapours. The crystal structure, derived from X-ray powder diffraction, yielded the sum formula Cu4Na4O(HCOO)8(OH)2·4H2O. Except for the absence of acetate in the structure, this is in good agreement with the 2002 publication. To assess which kind of combined glass/metal objects are affected, a number of large museum collections were surveyed. Sodium copper formate was detected as a corrosion product using mainly micro-Raman spectroscopy, for instance, on 18 painted Limoges enamels, eight glass vessels with metal mountings, glass beads on metal wire from 11 bridal crowns, nine Christmas tree balls with wire decoration, 40 pieces of jewellery with glass gems, three daguerreotypes, and one miniature with cover glasses. 相似文献
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OBJECTIVE: There has been relatively little attention given to positive adaptation following childhood sexual abuse (CSA), and typically such resilience has been explored primarily in the intrapersonal domain. This study explored questions about later resilience following CSA within a multidimensional framework by assessing resilience across intrapersonal, interpersonal, and intrafamilial domains. METHOD: This community sample consisted of 79 mothers with a history of CSA who had a child living at home with them. Participants completed four outcome measures (Center for Epidemiologic Studies--Depression Scale, Parenting Stress Index [PSI] Health Scale, PSI Parenting Competence Scale, and a measure of marital satisfaction). Risk and protective factors examined in relation to outcome included mother's age, socioeconomic status, severity of the CSA experience, coping strategy (avoidance, seeking social support, and problem solving), child characteristics, and spousal/partner support. RESULTS: Results indicated that when multiple adaptational domains were assessed, mothers showed discrepancies in how adequately they functioned across domains. While severity of the CSA experience was only weakly associated with outcome, use of avoidant coping emerged as a significant risk factor and was strongly and consistently associated with negative outcome across domains. Spousal/partner support was a strong protective factor and buffered the relationship between depressive symptoms and parenting competence. Difficult child characteristics were significantly associated with mothers' perceptions of physical health and parenting competence. CONCLUSIONS: The findings suggest the importance of comprehensive multimethod assessments of resilience and extend the knowledge of factors associated with positive outcome. The results highlight the need for further research exploring current contextual risk and protective factors associated with resilience in each domain. 相似文献
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When dealing with contemporary art, conservators have to address not only the material aspects of the artwork but also other highly complex issues. The Argentinian artist Leon Ferrari is a representative example. He created avant-garde art installations but also worked with traditional techniques. His works raise dilemmas over concepts such as authorship, authenticity, legitimacy of art. Some of his artworks only interested him as a means to express his opinions and he was not concerned about alterations in their appearance. Therefore, what should be kept in them is not in an area of certainty for conservators. An essential key for achieving a responsible and respectful conservation result, is to understand the ideology involved in each ‘art piece’ created by Ferrari. 相似文献
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Alexandra Ursache Kathleen Kiely Gouley Spring Dawson-McClure R. Gabriela Barajas-Gonzalez Esther J. Calzada Keith S. Goldfeld Laurie M. Brotman 《Child development》2020,91(6):e1249-e1266
This study examined longitudinal relations between emotion knowledge (EK) in pre-kindergarten (pre-K; Mage = 4.8 years) and math and reading achievement 1 and 3 years later in a sample of 1,050 primarily Black children (over half from immigrant families) living in historically disinvested neighborhoods. Participants were part of a follow-up study of a cluster randomized controlled trial. Controlling for pre-academic skills, other social–emotional skills, sociodemographic characteristics, and school intervention status, higher EK at the end of pre-K predicted higher math and reading achievement test scores in kindergarten and second grade. Moderation analyses suggest that relations were attenuated among children from immigrant families. Findings suggest the importance of enriching pre-K programs for children of color with EK-promotive interventions and strategies. 相似文献
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Gabriela Gonçalves Lily A. Arasaratnam-Smith Natércia Rodrigues Raquel Carvalheiro 《Journal of Intercultural Communication Research》2020,49(3):242-262
ABSTRACT This article explores the psychometric validation of an Intercultural Communication Competence (ICC) scale. Three studies were performed: (1) psychometric evidence pertaining to the scale’s reliability and factor structure and an analysis of the measurement invariance; (2) assessment of convergent and predictive validity; and (3) analyzes the association between ICC and affective and cognitive dimensions of cultural empathy. A three-factor model with eight items yielded the best fit to the data. The scale showed non-invariance between genders, but proved to be a predictor of intercultural contact. Convergent validity were demonstrated. 相似文献
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Gustavo Zaccaria Schaun Stephanie Santana Pinto Bruno Brasil Gabriela Neves Nunes Cristine Lima Alberton 《Journal of sports sciences》2019,37(14):1561-1569
The neuromuscular adaptations between ergometer-based high-intensity interval training (HIIT-T; n = 15), whole-body high-intensity interval training (HIIT-WB; n = 12) and moderate-intensity continuous training (MICT; n = 14) were compared in forty-one healthy men randomized to 16 weeks of training (3x per week). Two-way repeated measures analysis of variance (ANOVA) showed countermovement (CMJ) and squat (SJ) jump height (HIIT-T: 8.5 ± 13.3%; 3.1 ± 9.7%, HIIT-WB: 6.4 ± 9.8%, 10.4 ± 16.1% and MICT: 2.2 ± 9.5%; 4.4 ± 12.1%, respectively), SJ peak power (HIIT-T: 1.7 ± 3.9%; HIIT-WB : 6.4 ± 7.9%; MICT: 0.5 ± 6.5%) and CMJ rate of force development (HIIT-T: 58.1 ± 50.5%; HIIT-WB: 36.9 ± 54.2%; MICT: 38.4 ± 64.3%) improved similarly in all training groups (all p < 0.05). CMJ peak power increased only after HIIT-T (4.3 ± 5.5%) and HIIT-WB (4.5 ± 5.2%), while no differences were observed in both the rectus femoris and vastus lateralis maximal electromyographic amplitude. Finally, marked improvements were also observed in the number of repetitions in the HIIT-WB protocol at the eighth week, with no further improvement at the sixteenth week. These data suggest that 16 weeks of HIIT-WB is capable to improve neuromuscular function to a similar extent as HIIT-T and MICT. 相似文献
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