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Towards an integrated pelagic and benthic analysis of long-term coastal eutrophication (Guanabara Bay, Brazil)

Environmental Advances 2024年 15卷

作者： Muniz, Jaqueline Sá Earp Abuchacra, Rodrigo Coutinho Peixoto, Fernando Cunha Abuchacra, Paula Ferreira Falheiro Sanders, Christian J. Salgado, Carla Maciel Baptista Neto, José Antônio Amora-Nogueira, Leonardo Cordeiro, Renato Campello Moreira, Luciane Silva Pinho, Luana Valentin, Jean Louis Faustino, Allana Fonseca-Oliveira, Ana Pio, douglas Motta Carvalho, Manuela Lima Pinto, Samira Cristina de Souza Machado, Wilson Gomes, Luiz Eduardo de Oliveira Marotta, Humberto Chemical Engineering Graduate Program Universidade Federal Fluminense (UFF) Rua Passo da Pátria 156 RJ Niterói 24210-240 Brazil Ecosystems and Global Change Laboratory (LEMG-UFF) / International Laboratory of Global Change (LINCGlobal) Biomass and Water Management Research Center (NAB-UFF) Graduate Program in Geosciences (Environmental Geochemistry) Universidade Federal Fluminense (UFF) Av. Edmundo March s/n° RJ Niterói 24210-310 Brazil Department of Geography Graduate Program in Geography Universidade do Estado do Rio de Janeiro (UERJ-FFP) Rua Dr Francisco Portela 1470 São Gonçalo Rio de Janeiro 24435-005 Brazil Instituto Militar de Engenharia (IME) Praça General Tibúrcio 80 Praia Vermelha Rio de Janeiro 22290-270 Brazil Physical Geography Laboratory (LAGEF-UFF) Department of Geography Graduate Program in Geography Universidade Federal Fluminense (UFF) Av. Gal. Milton Tavares de Souza s/n° RJ Niterói 24210-346 Brazil National Marine Science Centre Faculty of Science and Engineering Southern Cross University Coffs Harbour 2450 NSW Australia Department of Geology and Geophysics/LAGEMAR Universidade Federal Fluminense (UFF) Av. General Milton Tavares de Souza s/n RJ Niterói 24210-346 Brazil Department of Chemical Oceanography Rio de Janeiro State University Pavilhão João Lyra Filho sala 4008 Bloco E Rua São Francisco Xavier 524 Maracanã – RJ 20550-900 Brazil Department of Marine Biology Federal University of Rio de Janeiro Rio de Janeiro Brazil NGO Guardiões do Mar Rua Alfredo Azamor 739 Boa Vista RJ São Gonçalo 24466-000 Brazil Silvestrum Climate Associates L.L.C. 1 Lower Crescent Ave Sausalito CA United States

Coastal ecosystems are important destinations for natural and anthropogenic inputs, areas experiencing eutrophication from untreated sewage globally. However, the mechanistic link of how coastal waters and sediments can jointly respond to nutrient enrichment, especially nitrogen (N) and phosphorus (P), remains relatively unknown. Here, we assessed the interdecadal variability in N and P contents, comparing four surface water sampling sites (∼40-year monthly concentrations) and three ²¹⁰Pb dated sediment cores (∼70-years) in an urban bay that has received increasingly high untreated sewage discharges over the past century (Guanabara Bay, Brazil). Major eutrophication was found, with differences between waters and sediments along sampling sites. The water concentrations of total phosphorus (TP) and dissolved inorganic nitrogen (DIN) yielded on average ∼10–45 % and ∼40–190 % higher in 2005–2017 compared to 1980–2005 period in the sampling site most influenced by the denser urban than the conserved area, respectively. Furthermore, 6-year average water concentrations indicated both recent initial decreases in the most urban area, potentially associated with new sanitation facilities, and high increases in those relatively more conserved areas. Conversely, TP and TN sediment burial rates were less sensitive to recent changes as compared to the water concentrations, yielding ∼11 and 31 % between 1980–2005 and 2005–2017, respectively, of which also provided baselines data for earlier periods without direct pelagic measurements (i.e., 1950–1980). Thus, these findings offer new insights into substantial temporal and intra-ecosystem spatial variability of coastal eutrophication, indicating that an integrated analysis between water monitoring and sediment burial is needed to improve the diagnosis and prediction capabilities necessary for effective long-term mitigation of coastal aquatic eutrophication worldwide. © 2023

关键词： 210Pb dating Coastal eutrophication Sediment burial Urban bay Water monitoring

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Formability of Third Generation Advanced High Strength Steel: Experimental and Theoretical Approach

SSRN

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SSRN 2024年

作者： Butuc, Marilena C. Vincze, Gabriela Santos, Rafael Pereira, António Santos, Abel D. Amaral, Rui L. Barlat, Frederic Centre for Mechanical Technology and Automation Department of Mechanical Engineering University of Aveiro Portugal LASI - Intelligent Systems Associate Laboratory Guimarães Portugal Graduate Program in Metallurgical Engineering Universidade Federal Fluminense Rio de Janeiro Volta Redonda Brazil Faculty of Engineering University of Porto R. Dr. Roberto Frias s/n Porto4200-465 Portugal INEGI – Institute of Science and Innovation in Mechanical and Industrial Engineering Portugal Graduate Institute of Ferrous Technology Pohang University of Science and Technology Korea Republic of

The aim of this paper is to evaluate, predict and analyze the plastic properties and formability of third-generation advanced high-strength steel (3genAHSS), with a specific focus on USS CR980XG3™️ AHSS as the reference material. Forming limit diagrams were determined, utilizing a range of experimental methods, including Nakajima tests, Erichsen tests, uniaxial tensile tests, and the Bulge test. A pivotal aspect is the application of an advanced sheet metal forming limit model based on Marciniak-Kuczynski analysis to simulate localized necking onset. Various constitutive equations, such as von Mises, Hill 48, and Yld2000-2d yield conditions, were used in simulation, alongside strain hardening laws like Swift and Voce. Comparative analyses were conducted to assess the accuracy of different models in predicting forming limits, with a particular emphasis on the influence of strain rate sensitivity. The study underscores the significant impact of the experimental method on forming limit values, highlighting that Yld2000-2d and the Swift hardening law with strain rate sensitivity provide optimal reproducibility of experimental data. Furthermore, the research emphasizes the necessity of considering strain rate sensitivity for accurate numerical simulations, stressing the effectiveness of the Marciniak-Kuczynski model when combined with proper constitutive equations in predicting forming limits for USS CR980XG3™️ AHSS. © 2024, The Authors. All rights reserved.

关键词： Strain hardening

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Trends in Membrane Distillation for Wastewater Treatment

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Journal of Environmental Protection 2021年第2期12卷 106-124页

作者： Graziela Salvan Cerveira Jorge Lima de Magalhães Adelaide Maria de S. Antunes Program of Engineering of Chemical and Biochemical Processes School of Chemistry Universidade Federal do Rio de Janeiro Rio de Janeiro Brazil Instituto Nacional da Propriedade Industrial (INPI) Rio de Janeiro Brazil Professional Postgraduation Program in Management Research and Development in the Pharmaceutical Industry Centre for Technological Innovation/NIT-FAR Oswaldo Cruz Foundation/FIOCRUZ Ministry of Health Rio de Janeiro Brazil Global Health and Tropical Medicine (GHTM) Instituto de Higiene e Medicina Tropical (IHMT) University NOVA of Lisbon (UNL) Rua da Junqueira Lisbon Portugal

Membrane distillation (MD) is a promising technology that enables the treatment of high-salinity wastewater. To monitor the state and trends of MD technology for wastewater treatment, the patent filings from the last nine years were analyzed. A total of 72 documents with a special focus either on the membrane itself or on the equipment and process were found. China, United States and Japan play a leading role in the development of these technologies. Most of the inventions concentrating on the membrane apply polymers as the material. Inventions describing the equipment and process are mainly related to system and module design, but also cover the combination of MD with other technologies, the treatment customization to a specific type of wastewater, fouling control and cleaning, and energy recovery. Finally, enhancements in water flux and energy efficiency are found to be key factors to broaden the application of MD technology in wastewater treatment.

关键词： Membrane Distillation Patents Trends Wastewater

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An Electronic Drive for a Switched Reluctance Motor Using a DSC 15

An Electronic Drive for a Switched Reluctance Motor Using a ...

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15th IEEE Brazilian Power Electronics Conference and 5th IEEE Southern Power Electronics Conference, COBEP/SPEC 2019

作者： Da Fonseca, Brayan Sobral Andres Santisteban, Jose COPPE - Universidade Federal Do Rio de Janeiro Graduate Program in Electrical Engineering Rio de Janeiro Brazil Universidade Federal Fluminense Graduate Program in Electrical and Telecommunications Engineering - PPGEET Niterói Brazil

ISBN: (纸本)9781728141800

With the technological advances using electronic circuits based on microprocessors, the drive and control of electrical machines in electromechanical systems have become increasingly efficient. In this paper, for an axial magnetic flux reluctance motor, for which it is not possible to supply its energy directly from the utility, the developing of an electronic drive and its control is described. Unlike other alternatives, a development module, named DSC (Digital Signal Controller), which is based on a modern microcontroller, allows the reduction of discrete components, like operational amplifiers, and wires. The workbench comprises a three-phase power converter that is equipped with high-speed semiconductor switches, current sensors, voltage sensors and an USB interface to allow communication with a computer. The effectiveness of this approach is verified through open loop and closed loop experimental tests, where the waveforms of the trigger pulses generated by the DSC, the motor currents and their speed were monitored. © 2019 IEEE.

关键词： Reluctance motors

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Geogrid-type geotextile made from Typha domingensis fibers with high tensile strength for erosion control

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Invention Disclosure 2024年 4卷

作者： Luiz Diego Vidal Santos Francisco Sandro Rodrigues Holanda Alceu Pedrotti Janisson Bispo Lino Cátia dos Santos Fontes Jeangela Carla Rodrigues de Melo Regina Helena Marino Gizelio Menzes Boge Universidade Federal de Sergipe-UFS Graduate Program in Agriculture and Biodiversity São Cristóvão Sergipe Brasil Universidade Federal de Sergipe-UFS Agronomy Engineering Department São Cristóvão Sergipe Brasil Universidade Estadual do Norte Fluminense Darcy Ribeiro Agronomy Engineering Department Rio de Janeiro Rio de Janeiro Brasil Secretaria de Educação do Estado de Sergipe SEED Aracaju Sergipe Brasil

The present invention relates to a geotextile of the geogrid type manufactured with fibers from the Typha domingensis plant, known as cumbungi, recognized for its remarkable tensile strength. This geotextile is developed to mitigate erosive processes and is produced from natural fibers arranged in a mat configuration. This product fit in with the technical fields of civil engineering and textile materials. The central innovation of this geotextile lies in the provision of a natural alternative featuring biodegradable fibers and high tensile strength. Its applications in environmental engineering include erosion prevention, slope stabilization, and reinforcement of road structures, with the fundamental goal of preserving the soil against degradation and erosion. This high-strength geotextile is composed of Typha domingensis fibers skillfully interwoven and connected to form a grid structure, with each unit covering approximately 0.25 m 2 s. Furthermore, a double layer of waterproofing material is incorporated to provide greater cohesion, environmental durability, and tensile strength. In practical applications, this geotextile demonstrates a remarkable ability to withstand mass movements even before local vegetation develops. This makes it a technological alternative that synergistically combines technological and ecological processes, incorporating the principles of soil bioengineering while offering a sustainable alternative to synthetic geotextiles. The use of this geotextile in the field is preferably combined with living components such as seeds, plant stakes, wood, or rocks for slope or embankment stabilization, with a primary focus on effective erosion control and the promotion of environmental sustainability.

关键词： Natural fiber Bioengineering Cumbungi Tensile strength Patent

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Sized-Controlled Pd Porous Nanospheres by a Non-Classical Growth Mechanism Combining the Lamer and Dlvo Theories and Their Catalytic Activities

SSRN

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SSRN 2022年

作者： de Lima, Scarllett L.S. Miguel, Vitor M. Rosado, Taissa F. Petri, Marcos V. Gardener, Jules Rodrigues, Thenner S. de Torresi, Susana Córdoba I. Solorzano, Guillermo da Silva, Anderson Gabriel Marques Rua Marquês de São Vicente 225 - Gávea Rio de Janeiro – RJ 22453-900 Brazil Departamento de Química Fundamental Instituto de Química Universidade de São Paulo Av. Prof. Lineu Prestes 748 São Paulo SP 05508-000 Brazil Center for Nanoscale Systems School of Engineering and Applied Sciences Harvard University United States Nanotechnology Engineering Program Alberto Luiz Coimbra Institute for Graduate Studies and Research in Engineering COPPE Federal University of Rio de Janeiro Av. Horácio Macedo 2030 RJ Rio de Janeiro 21.941-972 Brazil

We describe herein the synthesis of Pd porous nanospheres in a single reaction step by reducing PdCl 4 2- (aq) with hydroquinone. Simply by controlling the reaction temperature, we could obtain monodisperse Pd porous nanospheres with well-defined shapes and sizes. Based on the detected product morphology, crystallinity, and several control experiments, a novel non-classical mechanism based on both LaMer and DLVO theories was established. Specifically, Pd nanoclusters were produced at the initial stages of the reaction, followed by their fusion to form larger polycrystalline Pd nanoparticles. These polycrystalline Pd nanoparticles served as seeds for further Pd deposition and attachment of Pd nanoclusters to generate Pd porous nanospheres. In this procedure, the control over the temperature enabled us to tune the ionic strength of the solution (control over the fraction of PdCl 4 2- and K + ions present in solution), which affected the attachment and aggregation steps, leading to Pd porous nanospheres with controlled sizes and morphologies. When these nanomaterials were employed as nanocatalysts toward electrooxidation of ethanol, the 12 nm-Pd porous nanospheres were the best catalyst in terms in terms of both activity and peak potential. © 2022, The Authors. All rights reserved.

关键词： Palladium

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Author Correction: Compound dry-hot-fire events connecting Central and Southeastern South America: an unapparent and deadly ripple effect

npj Natural Hazards

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npj Natural Hazards 2024年第1期1卷 1页

作者： Djacinto Monteiro dos Santos Aline M. de Oliveira Julia A. Rodrigues Lucas S. Menezes Ronaldo Albuquerque Leonardo F. Peres Renata Libonati Ediclê S. F. Duarte Judith J. Hoelzemann Fabio de O. Roque Departamento de Meteorologia Universidade Federal do Rio de Janeiro Rio de Janeiro Brazil Instituto Dom Luiz (IDL) Faculdade de Ciências Universidade de Lisboa Lisboa Portugal Department of Atmospheric and Climate Sciences Graduate Program in Climate Sciences Federal University of Rio Grande do Norte Natal Brazil University of Évora - Institute of Earth Sciences Évora Portugal Universidade Federal de Mato Grosso do Sul Campo Grande Brazil Center for Tropical Environmental and Sustainability Science (TESS) and College of Science and Engineering James Cook University Cairns QLD Australia

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Compound dry-hot-fire events connecting Central and Southeastern South America: an unapparent and deadly ripple effect

npj Natural Hazards

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npj Natural Hazards 2024年第1期1卷 1-13页

South America has experienced severe compound drought-heatwaves (CDHW), exacerbating fires. Recently, the unprecedented Pantanal 2020 fire season (P20F), burning a third of the biome, resulted in well-reported local impacts on the ecosystem, economy, and health. Nevertheless, the long-range ripple effects of this event remain unknown. We investigated the P20F-related cascading hazards, integrating models, observational and satellite-based data. P20F-related smoke elevated PM2.5levels in the SA’s most populated area, exceeding WHO guidelines by up to 600%. Smoke-induced air pollution episodes coincided with widespread heatwaves, amplifying health risks. The mortality burden attributable to this multi-hazard short-term (14 days) exposure was estimated to be 2150 premature deaths (21% increase above expected levels). Our findings highlight that the impacts of CDHW-fires in SA are beyond the local level, implying growing challenges for risk management and public health and the need for governance based on telecoupled flows, linking different systems over multiple scales.

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Normal- and high-strength concretes with eco-efficient cementitious materials: Proportioning and evaluation of physical, mechanical, and durability properties

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Journal of Building engineering 2025年 111卷

作者： Joaquin Humberto Aquino Rocha Nahúm Gamalier Cayo Chileno Romildo Dias Toledo Filho Departamento de Ingeniería Civil Facultad de Ciencias y Tecnología - FCyT Universidad Mayor de San Simón - UMSS Cochabamba Bolivia Civil Engineering Program Instituto Alberto Luiz Coimbra de Pós-Graduação e Pesquisa de Engenharia COPPE Universidade Federal do Rio de Janeiro (UFRJ) Rio de Janeiro Brazil

This study evaluated the properties of ternary blends comprising Portland cement, recycled concrete powder (RCP), and metakaolin (MK) in producing normal-strength and high-strength concrete with target compressive strengths of 30 and 60 MPa, respectively. The concrete mixtures were designed using the Compressible Packing Model (CPM) to optimize the proportions of constituent materials and enhance physical and mechanical properties. Ternary blends with up to 30 % cement replacement by weight were prepared in the following proportions: 5 % MK + 25 % RCP, 10 % MK + 20 % RCP, and 15 % MK + 15 % RCP. Absorption, density, and void index were analyzed as physical properties, while compressive strength, splitting tensile strength, and elastic modulus were examined as mechanical properties at 7, 28, 90, and 180 days. Additionally, durability tests, including capillary water absorption, drying shrinkage, and rapid chloride permeability test (RCPT), were performed. The CPM-based approach successfully achieved the target compressive strengths, reaching 30.92 MPa and 63.07 MPa for normal- and high-strength concretes at 28 days, respectively. In long-term assessments, ternary blends exhibited enhanced strength and durability. For example, in high-strength concrete, water absorption decreased from 0.77 % to 0.68 %, and chloride ion penetration was significantly reduced from 1332.5C to 79.5C. These improvements were observed in mixtures incorporating 15 % MK and 15 % RCP at 180 days. The inclusion of MK effectively mitigated the dilutive effects of RCP, improving microstructural characteristics and reducing porosity, which consequently decreased water absorption and chloride ion penetration. The results suggest that optimally proportioned ternary blends can outperform conventional reference mixes, rendering them a viable solution for eco-friendly construction practices.

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The Oligocene/Miocene Boundary of Ilha de Santana and Pirabas Formations from the Pará-Maranhão and Barreirinhas Basins at the Equatorial Northwestern Platform of Brazil

SSRN

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SSRN 2023年

作者： Guimarães, Beatriz Teixeira Aguilera, Orangel Linhares, Ana Paula Oliveira de Araújo, Olga M. Mello, Isadora Costi, Hilton Tulio Sierra, Dayana Alvarado Kutter, Vinicius Lima, Daniel Correia Andrade Oliveira, Geize Carolinne Lopes, Ricardo Geoscience Institute Pará Belém Brazil Paleoecology and Global Changes Laboratory Rua Prof. Marcos Waldemar de Freitas Reis Campus Gragoatá Bloco M Lab 110 Niterói Rio de JaneiroCEP: 24210-201 Brazil Museu Paraense Emilio Goeldi Earth Sciences and Ecology Coordination Pará BelémCEP.66077-830 Brazil Nuclear Instrumentation Laboratory Nuclear Engineering Program/COPPE Cidade Universitária Av. Horácio Macedo Rio de JaneiroCEP. 21941-450 Brazil Santana do Cariri Ceará63190-000 Brazil Universidade Federal do Oeste do Pará Instituto de Engenharia e Geociências Campus Santarém Unidade Tapajós R. Vera Paz s/n Bairro Salé Brazil

Sedimentary carbonate outcrops of the Pirabas Formation at the Bragantina platform in North Brazil represent the exposed portion of the entire carbonate succession in the marine equatorial platform from the subsurface Ilha de Santana Formation (Cretaceous/Maastrichtian-Miocene/Aquitanian) in the Pará-Maranhão Basin and from the Pirabas Formation (Miocene/Aquitanian–Serravallian) in the Barreirinhas Basin, both from the Humberto de Campos Group. The transgressive deposits, flooding, and advance of the carbonate platform were investigated through the study of outcrops of the Pirabas Formation (type locality in the Ilha de Fortaleza, Pará state) and the analogous carbonate from the upper section of the Ilha de Santana Formation from the well-log 1-MAS-16-MA (510 to 660 meters below sea floor). The stratigraphic analyses were based on petrography, microCT, microfossil assemblages (foraminifera, ostracods, and bryozoans) and index species (Amphistegina, Archaias, Pyrgo, Quinqueloculina, Pirabasoporella, Nellia, Skylonia, and Alpheus), and biofacies approach (BF-3/BF-1). The bordering between the Ilha de Santana Formation (Aquitanian/Burdigalian at 510–660 mbsf section of 1-MAS-16-MA) and the Pirabas Formation (Burdigalian/Serravallian at the Ilha de Fortaleza outcrops) suggests that shallow-water sedimentary facies are similar to those deposited in the marginal basins and marks the start of siliciclastic supplies to the inner platform and the reduction of coralline algae carbonate factories. © 2023, The Authors. All rights reserved.

关键词： Computerized tomography

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