ABSTRACT Air navigation is increasingly dependent on the use of Global Navigation Satellite Systems (GNSS). It allows the determination of the aircraft’s position in all phases of the flight and brings many advantages. Although GNSS navigation results in gains, the radio signals from these systems are strongly influenced by the ionospheric environment. It introduces errors that can affect the accuracy, integrity, availability and continuity requirements established by the International Civil Aviation Organization (ICAO). The ionospheric layer has different behaviors depending on the latitude, time of day, season of the year, geomagnetic activity and solar cycle. Since Brazil is located in a region of low latitudes, it experiences a series of unique challenges when compared to regions of mid-latitudes. For this reason, the application of GNSS-based technologies in aviation over the Brazilian territory requires an in-depth assessment of the ionosphere effects. Therefore, the Instituto Nacional de Ciência e Tecnologia (INCT) named GNSS Technology for Supporting Air Navigation was formed in 2017 to better assess the ionosphere impacts and assist government agencies and companies in the development of safe air navigation procedures over Brazil in a near future. This paper presents the most relevant advances achieved so far within this multidisciplinary project that involves Brazilian research centers and universities.

RESUMO A evolução tecnológica é imprescindível para tornar a agricultura irrigada mais eficiente no uso da água. Sendo assim, esse artigo de revisão visa contextualizar a irrigação na era da agricultura 4.0 de forma a abordar como essas novas tecnologias estão a impactar no uso racional da água. No que concerne a automação de sistemas irrigados abordou-se a eficiência da irrigação com auxílio de sensores de umidade, aplicativos com uso de smartphone, controladores e injetores de fertilizantes e como o funcionamento destes pode promover a irrigação. Com relação ao manejo da irrigação, o uso do sensoriamento remoto como opção para determinação da evapotranspiração da cultura foi contextualizado, relacionando os tipos de bandas espectrais e sensores utilizados para a coleta de imagens (orbital, aéreo e terrestre), no acompanhamento do status hídrico da cultura. Versou-se também sobre a importância da coleta de dados nas delimitações das zonas de manejo para a irrigação de precisão e quais os possíveis avanços ainda podem ser alcançados no que concerne a obtenção e análise de dados. Por fim, conclui-se que, apesar da alta eficiência dos sistemas de irrigação automatizados, informações oriundas dos atributos do solo, clima e planta obtidas através da gama de dados fornecidos por sensores, serão responsáveis pela mitigação dos impactos globais ocasionados pela agricultura irrigada no futuro próximo, já que estas informações podem potencializar com máxima eficiência, a irrigação de precisão, reduzindo assim o consumo de água pela agricultura.

ABSTRACT Technological evolution is essential to make irrigated agriculture more efficient in the use of water. Thus, this review article aims to contextualize irrigation in the age of agriculture 4.0 in order to address how these new technologies are impacting the rational use of water. With regard to the automation of irrigated systems, irrigation efficiency with moisture sensors, applications using smartphone, controllers and fertilizer injectors, as well as how their operation can promote irrigation, was addressed. Regarding irrigation management, the use of remote sensing as an option to determine crop evapotranspiration was contextualized, listing the types of spectral bands and sensors used to collect images (orbital, aerial and terrestrial), in the monitoring of crop water status. The importance of data collection in the delineations of management zones for precision irrigation and what possible advances can still be achieved with regard to obtaining and analyzing data were also discussed. Finally, it is concluded that, despite the high efficiency of automated irrigation systems, information of soil, climate and plant attributes obtained through the range of data provided by sensors will be responsible for mitigating the global impacts caused by irrigated agriculture in the near future, since this information can enhance irrigation, with maximum efficiency, thus reducing water consumption by agriculture.

ABSTRACT New techniques for manufacturing of biomaterials using additive/substrate manufacturing such as melting laser sintering (SLM) or CAD/CAM milling use micrometric metal powders to build custom parts. CoCrMo alloys are commonly used as biomaterials due to biocompatibility, high corrosion resistance and good mechanical properties. In this work, Cr-Co-based powder was obtained by mechanical alloying of Cr-Co-Mo-W alloy, using different Ball/Powder-Ratios (BPR) and thermal treatments. The powders were deagglomerated and characterized by X-ray diffraction (XRD) and Scanning electron microscopy (SEM). Based on SEM micrographs, the particle size analysis was used to compare the particles spheroidizing degree, using Feret’s diameter. The XRD patterns shown Co(solid-solution) as crystalline phase. The results of particles size indicates a decrease of Feret’s diameter in BPR (Ball/Powder-Ratio) from 4:1 to 6:1 understanding that from this ratio there is no significant decrease of this relation but there is an average size increase with losses in morphological aspect. The comparison between atomized powders and powder developed in this work indicates that atomized products present relation close to one which indicates there is uniformity in the particles spherical shape. Comparing ground powders from 6:1 ratio (before and after thermal treatment) there is a considerable decrease of Feret’s diameter being it decreased from 1.75 to 1.4, an increase of about 46% in particles spheroidizing.

Abstract The Fazenda Bonfim emerald deposit lies within the Seridó Belt. It is a classic example of deposit formed through metasomatic interactions between Be-rich granite intrusions and Cr(± V)-rich mafic-ultramafic rocks. The setting of the emerald mineralization was built under strong strike-slip dynamics, which produced serpentinization and talcification of mafic-ultramafic host-rocks, and was followed by syn-kinematic emplacement of Be-rich albite granite, favoring hydrothermal/metasomatic processes. The structural control and lithological-contrast were fundamental to the fluid flow and the best ore-shoot geometry, developed in the S-foliation intra-plane at the contact zone (phlogopite hornfels) between mafic-ultramafic rocks and the albite granite. Subsequently, an albitization process, linked to the final-stage of magmatic crystallization, led to an overall mineralogical and chemical change of the albite granite. 207U-235Pb data revealed inheritance ages from Archean to Neoproterozoic and a crystallization age of 561 ± 4 Ma for albite granite. However, 40Ar/39Ar data revealed plateau age of 553 ± 4 Ma for phlogopite hornfels, interpreted as the closure time for the metasomatic event responsible for the nucleation and growth of emerald crystals. The short interval of time between U-Pb and Ar-Ar data indicates an intense, but not protracted, metasomatic history, probably due to low volume of intrusive magma.

ABSTRACT: Nitrogen fertilization and an appropriate cutting thickness can result in firmer sod that can be handled in less time with greater turfgrass regrowth during the subsequent cycle. This experiment was conducted on a sod production farm located in Capela do Alto, in the state of Sao Paulo, Brazil. The soil was a dystrophic Rhodic Hapludox (Oxisol) with a medium texture. The experiment had two statistical designs; the initial design was randomized blocks with seven treatments and four replicates. Treatments were five doses of liquid organo-mineral fertilizer (OMF) corresponding to 0, 100, 200, 300 and 400 kg ha−1 of nitrogen (N) with supplementation of phosphorous (P) and potassium (K) as well as two control treatments - one with 300 kg ha–1 of N as OMF and the other with 300 kg ha−1 of N-urea + P and K. At harvest, the adopted design was a split-plot type with four replicates in a 7 × 3 factorial arrangement with seven treatments as the main plot and three sod cutting heights (9, 16 and 22 mm) as subplots. Nitrogen doses in the form of OMF influenced the percentage of ground cover (PGC) by turfgrass in both cycles. The N dose of 300 kg ha−1 formed the sod more quickly and provided the largest mass of roots and stolons and the highest sod tensile strength. The thinnest sod samples had faster regrowth and provided higher PGCs.

RESUMO As florestas ciliares e de galeria localizadas no “arco do desmatamento”, vêm sofrendo degradação acelerada e, com a implantação do novo Código Florestal Brasileiro (Lei nº 12.651 de 2012), essas poderão ser reduzidas ainda mais. Diante desse fato, novos estudos acerca da produção de mudas para recuperação de áreas degradadas devem ser realizados com espécies nativas do domínio Amazônico e também do Cerrado. Por conseguinte, o objetivo do presente trabalho foi verificar em quais níveis de sombreamento, mudas de Calophyllum brasiliense, espécie típica de ambientes úmidos, apresentam os valores mais adequados de crescimento e eficiência de uso interno de nutrientes, visando a recomposição de áreas perturbadas. O estudo foi desenvolvido em viveiro florestal da UNEMAT de Nova Xavantina-MT. Avaliamos o crescimento das mudas em diâmetro, altura, número de folhas, produção de massa seca aérea e radicular, Índice de Qualidade de Dickson (DQI) e a Eficiência no Uso Interno de Nutrientes (EIUN) em casas de vegetação a 0 (pleno sol), 30, 50, 70 e 90% de sombreamento. De forma geral, os melhores resultados foram obtidos nos sombreamentos a 50 e 70%. Ecologicamente, a espécie responde melhor tanto em condições de clareira (50% de sombreamento) quanto em condições de dossel ou fechamento de clareira (70%). Nossos resultados demonstraram que as condições ideais para a produção de mudas desta espécie e maior EIUN, podem ser obtidas em condições de viveiro com 70% de sombreamento.

ABSTRACT Riparian and gallery forests located at the “arc of deforestation” have been undergoing fast degradation. With the implementation of the new Brazilian Forest Code (Law 12,651 of 2012), these can be reduced further. Thus, new studies on seedling production for ecological restoration should be carried out using native species from the Amazon and Cerrado. The objective of the present study was to assess under which shading levels the seedlings of Calophyllum brasiliense, a tree species typical of humid environments, show the highest values of growth and nutrient use efficiency, aiming at using these seedlings for restoration. The study was carried out in a plant nursery of the State University of Mato Grosso in Nova Xavantina, Brazil. We assessed seedling growth in diameter, height, number of leaves, production of shoot and root dry mass, Dickson quality index (DQI), and efficiency in the internal use of nutrients (EIUN) in greenhouses at 0 (full sunlight), 30, 50, 70, and 90% shading. The treatments at 50 and 70% shading showed the best results. Ecologically, the species responds well under both gap conditions (50% shading) and canopy or closing gap conditions (70% shading). Our results showed that the ideal conditions to produce seedlings of this species with high EIUN are obtained in greenhouses with 70% shading.

As florestas de galeria vêm sendo fragmentadas, levando à perda de sua elevada diversidade, tornando-se imprescindíveis estudos que avaliem o comportamento ecológico de suas espécies arbóreas. O presente estudo teve como objetivo testar a hipótese de que a produção de mudas de Copaifera langsdorffii é influenciada pela luminosidade do ambiente, apresentando maior qualidade e desenvolvimento inicial em níveis intermediários de luz. As plantas foram testadas em pleno sol, 30%, 50%, 70% e 90% de sombreamento, avaliando-se número de folhas, altura e diâmetro aos 60, 90, 120 e 191 dias após a emergência (DAE) e massa seca aérea e radicular e, índice de qualidade de Dickson ao final do experimento (191 DAE). O efeito dos níveis de sombreamento foi analisado por meio de análise de regressão. As plantas apresentaram boa plasticidade de crescimento nos diferentes níveis de luminosidade, mas com melhor desenvolvimento e qualidade (IQD) em 50% de sombreamento, corroborando a hipótese testada. A luminosidade ou sombreamento excessivo devem ser evitados para garantir a produção de mudas mais vigorosas de Copaifera langsdorffii. Assim, recomenda-se a produção de mudas desta espécie sob 50% de sombreamento para favorecer a sua qualidade e possivelmente garantir melhor sobrevivência em campo.

The gallery forests are being fragmented, leading to loss of its high diversity, becoming indispensable studies assessing the environmental performance of their tree species. The objective of this study was to test the hypothesis that the production of seedlings Copaifera langsdorffii is influenced by ambient light, higher quality and initial development at intermediate light levels. Plants were tested in full sun, 30%, 50%, 70% and 90% shading in order to evaluate the number of leaves, height and diameter at 60, 90, 120 and 191 days after emergence (DAE) and dry root and shoot biomass and Dickson quality index (DQI) at the end of the experiment (191 DAE). The effect of shading levels was analyzed by means of regression analysis. The plants showed good growth plasticity at different levels of lightness, but with better development and quality (IQD) at 50% shade, corroborating the hypothesis tested. The excessive lightness or shading should be avoided to ensure the production of more vigorous seedlings of Copaifera langsdorffii. Thus, production of seedlings of this species under 50% shade is recommended to promote their quality and possibly ensure better survival in the field.

RESUMO O objetivo deste trabalho foi a recuperação de descartes de ZrO2(Y2O3) oriundos de laboratórios de próteses dentárias, a partir do seu reprocessamento. Os descartes de ZrO2(Y2O3) foram fragmentados, peneirados e calcinados a 900ºC. Pós com tamanho menor que 32μm foram prensados uniaxialmente a 100MPa e sinterizados em temperaturas entre 1400 e 1600ºC-120min. Análise de difração de raios X realizadas nos materiais calcinados indicaram a presença majoritária da fase ZrO2 tetragonal. Os compactos apresentaram densidade a verde próximo a 47% e as amostras sinterizadas tiveram sua densidade relativa variando entre 83,5% e 95%, para temperaturas de sinterização de 1400 e 1600ºC, respectivamente. Os resultados da análise de difração de raios X indicaram a presença da fase ZrO2 tetragonal, com dureza Vickers e tenacidade máxima obtidos para as amostras sinterizadas a 1600ºC, da ordem de 1100 HV e 5,7 MPa.m1/2 respectivamente.

ABSTRACT The objective was the recovery of ZrO2(Y2O3) discarded arising from dentistry prosthetic laboratories. ZrO2(Y2O3) were fragmented, sieved and calcined at 900°C. Powders with size less than 32μm were uniaxially pressed to 100MPa and sintered at temperatures between 1400 and 1600ºC-120min. X-ray diffraction analysis performed on the calcined material showed the predominant presence of tetragonal ZrO2 phase. The green compact had the density close to 47% and sintered samples had a relative density ranging between 83.5% and 95% for sintering temperatures of 1400 and 1600ºC, respectively. The analysis results of X-ray diffraction indicated the presence of the tetragonal ZrO2 phase, with maximum Vickers hardness and toughness obtained for the samples sintered at 1600ºC, of the order of 1100 HV and 5.7 MPa.m1/2 respectively.

Resumo Depósitos de escarnitos mineralizados em W-Mo da Província Borborema são conhecidos desde os anos 40. Entretanto, até a execução deste trabalho, não se tinha registros desses depósitos mineralizados em Fe-Cu. No Ceará, as primeiras ocorrências e/ou depósitos de escarnitos ricos em ferro e cobre foram identificadas recentemente no Arco Magmático Continental de Santa Quitéria, considerado produto de evolução de vários arcos magmáticos, variando de arco juvenil (870 - 800 Ma) a colisão continental (625 - 600 Ma). Os escarnitos estão associados às rochas calcissilicáticas e mármores dolomíticos e/ou calcíticos, recortadas por quartzo monzonitos neoproterozóicos cedo a tardi-colisionais. São encontrados todos os tipos do sistema escarnítico como endoescarnitos, hornfels, escarnóides e exoescarnitos. Os exoescarnitos apresentam duas associações minerais, que refletem protólitos carbonáticos distintos: uma composta por clinopiroxênio-granada (estágio progradante) e magnetita-pirrotita-calcopirita-pirita-biotita (estágio retrogradante), característica de protólito calcítico, e outra formada por olivina-espinélio-diopsidio na fase progradante e serpentina na fase retrogradante, representativa de protólito dolomítico. As granadas, em parte zonadas, exibem composição dominada por andradita (82 - 52 mol%), seguida por grossularita (16 - 45mol%) e, em proporção menor, piropo (2 - 3 mol%). O piroxênio do protólito calcítico é típico da série diopsídio-hedenbergita, com composição média Diopsídio46Hedenbergita52Johannsenita2. Três tipos de minério magnetítico são encontrados: i) magnetito bandado; ii) magnetito disseminado; iii) magnetito maciço filoneano. Ocorre ainda um minério sulfetado de cobre com e sem magnetita associado, e blocos de gossans. Os dados geológicos e metalogenéticos obtidos indicam que a gênese destes escarnitos está associada à influência dos granitos monzoníticos tardi-brasilianos e, embora haja dois tipos de escarnito, predomina o mineralizado em ferro e cobre.

Abstract W-Mo skarns deposits in the Borborema Province have been known since the 40's, however, until this study there were no records of Fe-Cu skarns. In Ceará State, Brazil, the first occurrences of Fe-Cu skarns were identified recently in the Magmatic Arc of Santa Quiteria, product of superposition of several magmatic arcs, ranging from juvenile arc (870 - 800 Ma), up to continental collision (625 - 600 Ma). The skarns are associated with calc-silicate rocks and dolomitic and/or calcitic marbles, cut by Neoproterozoic, early to tardi-collisional quartz monzonite. In the area several skarn system types are found such as endoskarns, hornfels, skarnoids and exoskarns. The exoskarns show two mineral assemblages, reflecting different carbonate protolith: the first consists of clinopyroxene-garnet (prograde stage) and magnetite-pyrrhotite-chalcopyrite-pyrite-biotite (retrograde stage), characteristic of calcitic protolith, and the second, consists of olivine-spinel-diopside in prograde phase and serpentine in retrograde phase, representative of dolomitic protolith. Garnets partly zoned exhibit composition dominated by andradite (82 - 52 mol%) with subordinate grossularite (16 - 45 mol%) and minor pyrope (2 - 3 mol%). The pyroxene of the marble calcitic protolith is typical of the diopside-hedenbergite series, with average composition Diopside46Hedenbergite52Johannsenite2. Three types of iron-dominated skarn related ores are distinguished: i) banded magnetite; ii) disseminated magnetite; iii) vein massive magnetite. Takes place also a sulphide copper ore with and without associated magnetite and gossans blocks. The geological and metallogenic data obtained indicate that the genesis of these skarns are associated with the influence of monzonitic Brasilian granites and although there are two types of skarn, there is a predominance of Fe-Cu Skarn.

Testamos a hipótese de que a baixa diversidade de espécies lenhosas em uma floresta monodominante e possíveis fatores ambientais associados influenciam a ocorrência de samambaias na transição Cerrado-Floresta Amazônica. O objetivo foi analisar e comparar a riqueza florística, cobertura de dossel e aspectos ecológicos das samambaias em florestas de transição. As samambaias foram amostradas em uma floresta monodominante de Brosimum rubescens Taub. (MO) e uma floresta estacional mista (MI) em Nova Xavantina-MT. O substrato terrícola, a forma de vida hemicriptófita e o hábito herbáceo foram predominantes. A diversidade de espécies lenhosas foi superior à de samambaias, que apresentaram um total de 304 indivíduos, sete espécies, quatro gêneros e duas famílias. A família de maior riqueza foi Pteridaceae, representada por cinco espécies (71%). A floresta MI apresentou seis espécies, destacando-se Adiantum tetraphyllum Willd. com 209 indivíduos. Na MO foram encontradas apenas duas espécies, corroborando a hipótese de que a baixa diversidade de lenhosas influencia na diversidade de samambaias. Provavelmente, a cobertura do dossel, a qualidade da serapilheira e/ou fatores edáficos podem estar relacionados com a baixa diversidade de samambaias na MO, uma vez que tais condições podem atuar como filtro de espécies no ambiente monodominante, favorecendo somente as mais competitivas e adaptadas.

We tested the hypothesis that the low tree diversity in a monodominant forest and possible associated environmental factors influenced the ferns occurrence in the Cerrado-Amazon forest transition zone. The objective was to analyse and compare species richness, canopy cover and ecological aspects of ferns in the transitional forests. The ferns were sampled in a Brosimum rubescens Taub. monodominant forest (MO) and a seasonal mixed forest (MI). The terrestrial substrate, hemicryptophytes life form and herbaceous habit were prevalent. The diversity of woody species was higher than that of ferns, which had a total of 304 individuals, seven species, four genera and two families. The richest family was Pteridaceae, represented by five species (71%). MI forest presented six species and Adiantum tetraphyllum Willd. was the principal, with 209 individuals. Only two species were registered in the MO forest, supporting the hypothesis that low tree diversity and associated environmental conditions influences the diversity of ferns. Probably the canopy cover, the quality of the litter layer and/or edaphic factors may be related to the low diversity of ferns in the MO, since such conditions may act as an environmental filter of species, favoring only the most competitive and adapted to such conditions.