Santa Catharina Research Articles

Cooling rates and impact histories of group IAB and other IAB complex iron meteorites inferred from zoned taenite and the cloudy zone

AbstractMetallographic cooling rates of 10–20 K Myr−1 were obtained for four IAB iron meteorites from electron probe analyses of taenite and models simulating kamacite growth. Cooling rates were also determined for 21 irons in the IAB complex from the size of tetrataenite particles in the cloudy zone and a calibration curve using data for the four IAB irons and five other iron and stony iron groups. We find that the closely related IAB main group, low‐Au subgroups, Pitts grouplet irons, and San Cristobal cooled through 500 °C at 10–35 K Myr−1. The ungrouped IAB complex irons, Santa Catharina and Twin City, have bulk Ni contents of ~30 wt% and cooled much faster at ~200–1000 K Myr−1, most probably in a different parent body. Our cooling rates and observations allow conflicting interpretations of the nature of the low‐Ni phase in the cloudy zone to be reconciled. We infer that in fast cooled irons like Santa Catharina, the low‐Ni phase transforms to antitaenite, but in very slowly cooled meteorites like mesosiderites, martensite forms instead. In meteorites with intermediate cooling rates like IAB irons, the bulk of the cloudy zone probably contains antitaenite as the low‐Ni phase, but in the coarse region next to tetrataenite, martensite is present. Published isotopic ages show that metal–silicate mixing in group IAB irons occurred ~5–10 Myr after CAI formation, but the nature and timing of the impact are poorly constrained at present. Ar‐Ar ages testify to shock reheating of plagioclase during cooling over ~100 Myr. However, the cloudy zone is well preserved showing that metal was not heated significantly by shocks after slow cooling through 400 °C.

FAULT INSPECTION BY AERIAL INFRARED THERMOGRAPHY IN A PV PLANT AFTER A METEOROLOGICAL TSUNAMI

Infrared thermography (IRT) has been applied as an effective tool for detecting faults in PV modules. In addition, with the recent development of Unmanned Aerial Vehicles (UAV), they have been used in order to increase the cost-effectiveness and employ IRT for large-scale PV plants or roof-mounted PV systems. With the goal of demonstrating the capabilities of the UAV application, especially in aerial thermography analysis, this article presents an experiment applying UAV based IRT, performed for the fault inspection of a PV plant in South Brazil. The local is a 3 MWp PV plant located in the city of Tubarão in the state of Santa Catharina and consists of three 1 MWp-blocks of different PV technologies. On October of 2016, the plant was affected by a meteorological tsunami, causing several damages. The experiment was focused on the detection of the damages on the polycrystalline PV block of the power plant and a DJI Phantom 3 Advanced was equipped with a lightweight infrared camera to perform the aerial IRT. The measurements in the plant were performed in accordance with the international norm IEC TS 62446-3, under stable radiation and weather conditions, exclusively with irradiances above 800 W/m2 and average wind speeds of 3 m/s. The IRT drone system was essential for identifying damaged and defect portions of the PV power plant fast after the incident. It was possible to detect hot spots, defective bypass-diodes, short- and open-circuited strings. The damages could be noticed even when the UAV flight was at 40 m of altitude. The UAV based IRT assessment helped to identify the defects in a fast manner, without interrupting the power generation. It can be concluded that the technique is very effective, practical and relevant for damage inspection in large PV power plants.

Allabogdanite, the high-pressure polymorph of (Fe,Ni)2P, a stishovite-grade indicator of impact processes in the Fe\u2013Ni\u2013P system

Allabogdanite, (Fe,Ni)2P, is the only known natural high-pressure phase reported in the Fe–Ni–P system. The mineral, which was previously described from a single meteorite, the Onello iron, is now discovered in the Santa Catharina and Barbianello nickel-rich ataxites. The occurrence of allabogdanite in Santa Catharina, one of the largest and well-studied meteorites, suggests that this mineral is more common than was believed. The formation of allabogdanite-bearing phosphide assemblages in a given meteorite provides evidence that it experienced peak pressure of at least 8 GPa at a temperature above 800 °C. Since the pressure-temperature stability parameters of allabogdanite fall within the margins of the stishovite (rutile-type SiO2) stability area, the former can be employed as a convenient stishovite-grade indicator of significant impact events experienced by iron and stony-iron meteorites and their parent bodies.

Associação do status social subjetivo e indicadores sociodemográficos em atletas

DOI: http://dx.doi.org/10.5007/1980-0037.2016v18n5p591 Subjective social status comprises the perception of individuals about their social status. The aim of this study was to investigate the relationship between subjective social status and sociodemographic indicators (age, educational level, marital status and economic level) in athletes from Santa Catharina. A total of 593 athletes of both sexes and mean age of 21.18 (± 5.58) years, 371 men, randomly selected, practitioners of individual and collective sport modalities, federated in clubs in the western region of Santa Catarina participated in the study. Social status perception was assessed using the MacArthur scale version for young people adapted to the sports context. For the association between perceived status and sociodemographic indicators, the Chi-square and Multinomial Logistic Regression tests were used, stratified by gender and adjusted for age variables, educational level, marital status and socioeconomic status. Dissatisfaction with status was found in 85% of the sample. Moreover, 46.9% of participants perceived themselves with low family status and 46% perceived themselves with intermediate status in their clubs. The association between groups showed statistically significant differences according to sex, age, educational level and marital status. The association between sociodemographic variables and status according to sex indicated that younger men, with less education, and single were more likely to be dissatisfied with their status. There is need for greater attention by health professionals regarding younger male athletes, with lower education and single regarding their status perception.

A POLÍTICA DE ACESSO À TERRA NO BRASIL IMPERIAL E A COMPRA DE TERRAS DEVOLUTAS NO PLANALTO DA PROVÍNCIA DE SANTA CATARINA

This paper aimed to present a brief historiographical debate on land politic in Imperial Brazil, and the study related to the implementation of the 1850 Land Law in the province of Santa Catharina Plateau(Law No. 601 of September 18, 1850 and Decree No. 1318 of January 30, 1854 which regulates the implementation of the Law), with emphasis in Lages and in the parishes of Curitibanos and Campos Novos (emancipated of the jurisdiction of Lages during the last decades of the nineteenth century). The study was conducted based on purchasing requirements of devolutas (vacant) lands, produced between 1850 and 1889, provided by the law as the only legal form of access to land. As an agricultural frontier and population expanding, in the nineteenth century, the Santa Catarina Plateau was occupied in different ways - that go beyond the provisions of Law -, which reverberated in complex regulatory strategies of the property.

A DIVERSIDADE VAI A CRECHE: REFLEXÕES SOBRE A IMPLEMENTAÇÃO DA LEI FEDERAL 10.639/03 NA CRECHE DO MORRO DA QUEIMADA EM FLORIANÓPOLIS

This article aims to problematize and discuss the implications of Federal Law n.⁰ 10.639/03 at the Nursery School Morro da Queimada, which belongs to the Municipal Education System of Florianopolis/SC. The article is based on a survey of Child Education regulations and on the National Guidelines for Education of Racial Ethnic Relations and Afro-Brazilian and African Culture (BRASIL, 2003). The aim is to deepen the analysis concerning the pedagogical practices that motivated the investigation about the contradictions and actions in the routine of a school that aims to promote racial equality. To this end, the research focuses on two aspects: normative whiteness and curricula decolonization. Considering such complexity, the aims are to analyze the application of Federal Law n.⁰ 10.639/03 articulating it with the policies of equality racial promotion at the Municipal Child Education System in Florianopolis/SC to verify the mechanism used to construct an education aimed at the promotion of racial equality. This article is the result of the outreach project “Support to Public Policies for the Implementation of Federal Law n.⁰ 10.639/03 in Santa Catharina”, which is linked to the Program Antonieta de Barros Memorial from the Center of Afro-Brazilian Studies at UDESC (University of the State of Santa Catarina). It is expected that this study can contribute to overcome contradictions, promote the debate about racial relations and the implementation of Federal Law n.⁰ 10.393/03 in the institution analyzed, point out ways so that there can be a collective adherence to the proposal in addition to the discovery of methodologies for the effective application of the law in pedagogical practices.

Thermal and collisional history of Tishomingo iron meteorite: More evidence for early disruption of differentiated planetesimals

Tishomingo is a chemically and structurally unique iron with 32.5wt.% Ni that contains 20% residual taenite and 80% martensite plates, which formed on cooling to between −75 and −200°C, probably the lowest temperature recorded by any meteorite. Our studies using transmission (TEM) and scanning electron microscopy (SEM), X-ray microanalysis (AEM) and electron backscatter diffraction (EBSD) show that martensite plates in Tishomingo formed in a single crystal of taenite and decomposed during reheating forming 10–100nm taenite particles with ∼50wt.% Ni, kamacite with ∼4wt.%Ni, along with martensite or taenite with 32wt.% Ni. EBSD data and experimental constraints show that Tishomingo was reheated to 320–400°C for about a year transforming some martensite to kamacite and to taenite particles and some martensite directly to taenite without composition change. Fizzy-textured intergrowths of troilite, kamacite with 2.7wt.% Ni and 2.6wt.% Co, and taenite with 56wt.% Ni and 0.15wt.% Co formed by localized shock melting. A single impact probably melted the sub-mm sulfides, formed stishovite, and reheated and decomposed the martensite plates. Tishomingo and its near-twin Willow Grove, which has 28wt.% Ni, differ from IAB-related irons like Santa Catharina and San Cristobal that contain 25–36wt.% Ni, as they are highly depleted in moderately volatile siderophiles and enriched in Ir and other refractory elements. Tishomingo and Willow Grove therefore resemble IVB irons but are chemically distinct. The absence of cloudy taenite in these two irons shows that they cooled through 250°C abnormally fast at >0.01°C/yr. Thus this grouplet, like the IVA and IVB irons, suffered an early impact that disrupted their parent body when it was still hot. Our noble gas data show that Tishomingo was excavated from its parent body about 100 to 200Myr ago and exposed to cosmic rays as a meteoroid with a radius of ∼50–85cm.

Tigela, café e xícara: diversidade formal e dinâmicas de consumo na produção das louças brancas da cidade de São Paulo no começo do século XX

Este artigo apresenta algumas reflexões em torno das formas e volumes das louças em faiança fina produzidas, e consumidas, na cidade de São Paulo, durante o período de 1913 e 1937, relacionando-as a alguns hábitos levados a cabo na Paulicéia, como o crescente costume do "cafezinho". Para tal, parte-se das análises do acervo gerado pelo resgate do sítio arqueológico Petybon, localizado na zona metropolitana da cidade, no bairro da Lapa, região da Água Branca/Vila Romana. Aponta-se que a diversidade de formas das louças dialoga com os projetos de modernidade pensados para São Paulo e as demandas dos consumidores cujas diversas práticas culturais influenciaram na produção das faianças finas pela Fábrica de Louças Santa Catharina e Indústrias Reunidas Fábricas Matarazzo.

X‐ray Spectromicroscopy of Mineral Intergrowths in the Santa Catharina Meteorite

This work describes the application of microfocus X‐ray absorption spectroscopy (XAS) and X‐ray photo‐emission electron microscopy (XPEEM) to the study of the complex mineralogical intergrowths within the Santa Catharina meteorite. The Santa Catharina meteorite of this study (BM52283 from the meteorite collection of the Natural History Museum, London, UK) primarily comprises a taenite bulk host phase (Fe:Ni ratio = 70.9 ± 0.8%:29.1 ± 0.8%) with a set of oxide‐bearing cloudy zone textured regions (Fe:Ni:O ratio = 40.4 ± 0.3%:49.0 ± 0.7%:10.6 ± 0.8% at the core and Fe:Ni:O ratio = 34.4 ± 1.5%:42.7 ± 0.6%:22.9 ± 1.8% towards the rims) and numerous schreibersite (Fe:Ni:P ratio = 38.6 ± 1.6%:38.4 ± 0.9%:23.0 ± 0.5%) inclusions. Between the schreibersite and the taenite are rims up to 50 μm across of Ni‐rich kamacite (Fe:Ni ratio = 93.4 ± 0.4%:6.6 ± 0.5%). No chemical zoning or spatial variations in the Fe and Ni speciation was observed within either the schreibersite or the kamacite phases. The oxide‐bearing cloudy zone textured regions mostly comprise metallic Fe–Ni alloy, predominantly tetrataenite. Within the oxide phases, the Fe is predominantly, but not entirely, tetrahedrally co‐ordinated Fe3+ and the Ni is octahedrally co‐ordinated Ni2+. Structural analysis supports the suggestion that non‐stoichiometric Fe2NiO4 trevorite is the oxide phase. The trevorite:tetrataenite ratio increases at the edges of the oxide‐bearing cloudy zone textured regions indicating increased oxidation at the edges of these zones. The spatial resolution of the XPEEM achieved was between 110 and 150 nm, which precluded the study of either the previously reported ∼ 10 nm precipitates of tetrataenite within the bulk taenite or any antitaenite.

Barbianello: An ungrouped nickel‐rich iron meteorite found in Italy

Abstract— An unusual iron was found in 1960 in Barbianello (northern Italy, Pavia municipality) by a farmer, Clemente Allini, ploughing his fields. Years later, the iron was recognized as a meteorite but not officially classified. Our investigations indicate that Barbianello is a unique nickel‐rich ataxite with dark and light regions texturally similar to, but compositionally distinct from, Santa Catharina iron. The light regions are chemically homogeneous, have a Ni content of 27.1 wt%, and a composition similar to irons of group IAB‐IIICD. The dark regions are inhomogeneous with Ni ranging from 40 to 58 wt% and oxygen up to 20 wt%. Relics of unoxidized metal and textural relationships indicate that, unlike Santa Catharina, the dark regions result from the oxidation of a metal compositionally distinct from that of light regions.

Trade Diaspora versus Colonial State: Armenian Merchants, the English East India Company, and the High Court of Admiralty in London, 1748–1752

This article offers a non-fictional detective story that enables, and is embedded within, a larger analytical narrative. For reasons that will become clear, I as a historian and archival researcher play an unusually large role in the detective story, a tale of how I tracked down documents that enabled me to reconstruct an act of British colonial-era piracy against merchants of the Armenian trade diaspora in the eighteenth century. At the center of the narrative is an Armenian-freighted merchant ship called the Santa Catharina, whose cargo the British Admiralty confiscated in India in 1748 and for the possession of which a complex trial was conducted in London between 1749 and 1752. The case pits a trade diaspora against a state, and the analytical narrative discusses the contestation between the waxing power of an imperial nation-state and the waning power of a transnational diaspora. My article situates the Santa Catharina trial in a context in which a form of familial–ethnic merchant capital competed with a national-stock-holding merchant capital (that is, the English East India Company), worked with as well as clashed against it, all in an environment increasingly dominated by the colonial conflicts of Britain, France, and the nawab states of India. That larger context was shaped by the everincreasing reach of the British state, the English East India Company it chartered, and the navy and law courts that enforced the company’s privileges and encroachments.

The effect of high external magnetic fields on the hyperfine interactions in the Fe-Ni phases of the Santa Catharina meteorite

A thin slice of the Santa Catharina meteorite has been measured at 4.2 K in applied fields of 20, 40, 60, 90, and 120 kOe. The spectra were fitted adequately with a superposition of five quadruplets. Two of these are attributed to Fe72Ni28 with effective fields, suggesting that part of that phase is ferromagnetically ordered and part is paramagnetic. Two other components arise from crystallographically ordered FeNi, with the EFG principal axis parallel and perpendicular, respectively, to the effective field. The fifth subspectrum is due to unordered FeNi. The ordering in the FeNi phases is ferromagnetic and the magnitude of the effective fields can be explained in terms of dipolar and demagnetizing fields.

An overlooked fragment of the Santa Catharina ataxite

Abstract— An undocumented mass of 28 kg, recovered from a museum collection, is examined by several methods: optical microscopy, scanning electron microscopy, X‐ray diffraction, Mössbauer spectroscopy and chemical analyses by atomic absorption, energy‐ and wavelength‐dispersive X‐ray spectrometry and, with respect to the trace elements Ir, As, Au, by neutron activation. The structure and the mineralogical chemical composition of the mass identify it as a fragment of the Santa Catharina iron meteorite from Brazil.

An APFIM investigation of a weathered region of the Santa Catharina meteorite

An atom probe field ion microscope characterization has been performed on a weathered region of the Santa Catharina meteorite (USNM #3043). This meteorite consists primarily of a metallic matrix, oxides, and Schreibersite (FeNi) 3P. The metallic matrix was found to have decomposed into a random distribution of ∼ 12 nm diameter precipitates with compositions ranging from 38.6–54 at.% Ni in a matrix with lower nickel levels. Atom probe composition profiles between precipitates revealed a characteristic W-shaped nickel profile ranging from approximately 15% nickel adjacent to the precipitates to approximately 25% nickel in the central region away from the precipitates.

Temperature dependence of the Mössbauer parameters of the Fe−Ni phases in the Santa Catharina meteorite

The temperature variation in the range 8–760K of the hyperfine parameters of the Fe−Ni phases in the Santa Catharina meteorite has been determined. It is suggested that the disordered 50–50 Fe−Ni phase actually consists of two distinct fractions, i.e. a completely disordered phase and one with intermediate long-range ordering parameter. The single-line subspectrum of the 28%-Ni phase was found to display magnetic ordering below approximately 25K.

Application of the Mössbauer effect to the study of meteorites—A review

Mossbauer and X-ray diffraction studies revealed that segregation and ordering of Fe−Ni alloys occurs in meteorites in close resemblance with irradiation effects in these alloys. In Santa Catharina (35% Ni) and Twin City (30% Ni) ataxites, the ordering mechanism leads to the formation of rather large amounts of the 50–50 Fe−Ni ordered phase with tetragonal symmetry (tetrataenite). Furthermore this ordered phase has also been detected in metal particles of chondrites.

Electron microscopy study of the iron meteorite Santa Catharina

Abstract— Characterization of the microstructural features of the metal of the Santa Catharina meteorite was performed using a variety of electron optical techniques. Sample USNM#6293 is chemically homogeneous on the micron scale and has a Ni content of 28.2 wt.%. Its microstructure is similar to that of the Twin City ataxite and contains clear taenite II, i.e., fcc taenite with domains of tetrataenite, < 10 nm in size. Sample USNM#3043 is a more typical Santa Catharina specimen with dark and light regions as observed with the light optical microscope. The dark regions are inhomogeneous and contain 45–50 wt.% Ni and 7–12 wt.% O. The light regions are homogeneous and contain 35 wt.% Ni and no detectable oxygen. The microstructure is that of cloudy zone, i.e., islands of tetrataenite, ∼20 nm in size, in a honeycomb matrix. The honeycomb phase contains Ni rich oxide in the dark regions and contains metal, fcc taenite, in the light regions. The original metal structure of USNM#3043 is cloudy zone which formed during cooling into the low temperature miscibility gap of the Fe‐Ni phase diagram. The dark regions were developed from the metal by selective corrosion of the honeycomb structure, transforming it into Ni containing oxides, possibly non‐stoichiometric Fe2NiO4 while retaining the tetrataenite islands. Using the results of this study, many of the existing discrepancies concerning the microstructure of Santa Catharina can be explained.

Redescriptions ofSigambra grubiiMüller, 1858 andHermundura tricuspisMüller, 1858 from Brazil and designation of neotypes (Polychaeta: Pilargidae)

Fritz Müller (1858) described polychaetes from Santa Catharina Island, Brazil. His type material was lost and his descriptions were brief. In an attempt to clarify the taxonomic status of his pilargids and to complete a revision of the pilargid genera of the world, some polychaetes collected at the type locality were analysed. On the basis of 16 specimens, Sigambra grubii is redescribed and the differences from S. bassi (Hartman, 1945) are clarified; S. grubbi is smaller and its median antenna is shorter than that of S. bassi. With one specimen of Hermundura tricuspis, the differences from other species are recognized, and Hermundura is regarded as a junior synonym of Parandalia Emerson & Fauchald, 1971. Neotypes are designated and deposited in the Smithsonian Institution. Keys to all species are also included for both genera.

Solid state transformations in Fe-Ni alloys from meteorites in powder form

We report here Mossbauer studies by transmission and back-scattering technics, with Cape York and Santa Catharina meteorites in powder form. Martensitic transformation γ-phase to α-phase is induced by mechanical treatment and long-range order is affected.

A study of Ni-rich iron meteorites

Samples from the two Ni-rich iron meteorites Santa Catharina and Twin City have been investigated by conventional Mossbauer spectroscopy and by conversion electron Mossbauer spectroscopy. The spectra obtained show that the major components of these two meteorites are an ordered FeNi (∼50%, ∼50%) phase and a paramagnetic Fe−Ni phase with ≤28% Ni.