Article
Geochemistry & Geophysics
Joan Antoni Parera-Portell, Flor de Lis Mancilla, Jose Morales, Javier Almendros, Vanessa Jimenez-Morales
Summary: The Bransfield Strait region exhibits a homogeneous crust structure in the Antarctic Peninsula and an heterogeneous crust in the South Shetland archipelago, with variations in crustal thickness and Vp/Vs ratio from east to west. Additionally, evidence of underplating, shallow Moho, and widespread partial melting in the upper mantle is observed in the region.
Article
Microbiology
Javier Vicente, Miguel de Celis, Alejandro Alonso, Domingo Marquina, Antonio Santos
Summary: Deception Island in Antarctica is a geothermal location with active fumaroles, creating a unique habitat for microbial communities. A multidisciplinary study on sediments deposited over 4 years revealed a bacterial community dominated by Proteobacteria and Thaumarchaeota, a fungal community mainly composed of Aspergillaceae, and the presence of diatoms. The study highlighted the significant influence of physicochemical conditions on microbial populations and their distribution, providing valuable data on the interaction between the island and water microbiota.
Article
Microbiology
Amanda Goncalves Bendia, Leandro Nascimento Lemos, Lucas William Mendes, Camila Negrao Signori, Brendan J. M. Bohannan, Vivian Helena Pellizari
Summary: Active volcanoes in Antarctica have remarkable temperature and geochemical gradients that could select for a wide variety of microbial adaptive mechanisms and metabolic pathways. Microbial communities from different temperature environments showed distinct metabolic potentials and survival strategies, reflecting their adaptability to extreme conditions.
ENVIRONMENTAL MICROBIOLOGY
(2021)
Article
Chemistry, Inorganic & Nuclear
Digambar Y. Nadargi, K. P. Shinde, Mohaseen S. Tamboli, Pavan M. Kodam, Ambar V. Ghadage, Nguyen Tam Nguyen Truong, J. S. Park, Sharad S. Suryavanshi
Summary: The electrochemical performance of divalent (Mn, Fe, Zn) substituted NiCo2O4 nanorods, developed using a facile hydrothermal route, was investigated. Mn substitution showed the best performance among the divalent replacements, exhibiting a specific capacitance of 1272 F/g, an energy density of 35.77 Wh/kg, and a power density of 660.39 W/kg. Fe and Zn substitution resulted in lower capacitance compared to pure NiCo2O4, likely due to lower catalytic activity. Mn substituted NiCo(2)O(4) demonstrates the potential for high performance supercapacitor applications.
INORGANIC CHEMISTRY COMMUNICATIONS
(2022)
Article
Geology
Xian Chen, Xiaoming Sun, Zhongwei Wu, Jianlin Liao, Hongjun Chen
Summary: Detailed analyses were conducted on Si-(Fe) hydroxide formations, planktonic foraminifera, and Fe-Mn coatings from a sediment sample near an active hydrothermal vent field at the Southwest Indian Ridge. The results show diverse sources, unique microtextures, and influences of hydrothermal activity, bacterial precipitation, and diagenetic processes.
ORE GEOLOGY REVIEWS
(2021)
Article
Geochemistry & Geophysics
Vesselin M. Dekov, Olivier Rouxel, Bleuenn Gueguen, Anna Wegorzewski, Alexis Khripounoff, Lenaick Menot
Summary: The Mn-micronodules and nodules in the Clarion-Clipperton zone of the Pacific Ocean are made up of different components with different formation processes. The Mn-micronodules are mainly diagenetic in origin, while the Mn-nodules are diagenetic-hydrogenic. The fluctuation of the oxic-suboxic front since the Last Glacial Period may have contributed to the formation of the Mn-micronodules.
Article
Chemistry, Multidisciplinary
Jinxing Yang, Changji Li, Tianjia Guang, Hui Zhang, Zhaojin Li, Bingbing Fan, Yonghui Ma, Kongjun Zhu, Xiaohui Wang
Summary: The study demonstrates that LiMn0.5Fe0.5PO4 solid solution nanocrystals undergo a single-phase transition with zero lithium miscibility gap, exhibiting excellent electrochemical properties and an energy density 16% higher than LiFePO4. The high-performance nanocrystals are prepared by a microwave-assisted hydrothermal synthesis in pure water.
Article
Materials Science, Multidisciplinary
H. Khaleghi, M. H. Ehsani
Summary: This work investigated the structural, magnetic, and optical properties of pure CuO and double-substitution by Fe and Mn ions prepared by the hydrothermal method. Various techniques were used to study the structural and morphological properties. The results showed that the samples exhibited a polycrystalline monoclinic and nanosheet structure. The optical bandgap of the samples was obtained using UV-vis analysis. Vibrating-sample magnetometry revealed paramagnetic behavior in pure CuO and weak ferromagnetic behavior in the other samples.
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
(2022)
Article
Engineering, Environmental
Feng Pan, Yu Cai, Zhanrong Guo, Yuyao Fu, Xindi Wu, Huatai Liu, Xinhong Wang
Summary: Estuarine sediments play a crucial role in the transport and mobility of molybdenum (Mo) from rivers to the ocean. The geochemistry of manganese (Mn) in estuarine sediments is key in the mobility of dissolved Mo, with oxic intertidal sediments acting as Mo sinks and anoxic subtidal sediments functioning as Mo sources. Redox conditions and physicochemical processes are important factors controlling Mo mobility in estuarine sediments.
JOURNAL OF HAZARDOUS MATERIALS
(2021)
Article
Biodiversity Conservation
Wenyan He, Lihua You, Min Chen, Youcai Tuo, Ning Liao, Hongwei Wang, Jia Li
Summary: Water hypoxia in lakes and reservoirs is increasing globally due to global warming. The interpretation of the Mn/Fe ratio for reconstructing historical redox conditions may be problematic because factors other than redox processes can affect the accumulation of Fe and Mn. In this study, the Fe and Mn contents and bacterial diversity in the sediment of a monomictic reservoir were examined to determine the deposition time frame and sedimentary rate. It was found that the Mn/Fe ratio alone is not sufficient for interpreting the historic oxygenation regimes of reservoirs, and factors such as runoff sediment input, hydrodynamic characteristics, and bacterial distributions should be considered.
ECOLOGICAL INDICATORS
(2023)
Article
Geology
Fei Huang, Yu Fu, Dengfeng Li, Jinzhou Peng, Wentao He, Saiyu Li, Xiaoming Sun, Gaowen He
Summary: This study used in situ trace element and Nd isotope analyses to investigate the migration mechanism and geochemical characteristics of rare earth elements and yttrium (REYs) from Fe-Mn (oxyhydr)oxides to bioapatite in deep sea sediments. The results showed that high actinide REYs were primarily adsorbed onto bioapatite during early diagenesis, while low actinide REYs were mainly substituted for Fe-Mn (oxyhydr)oxides. Different morphological and geochemical types of Fe-Mn nodules provided insights into the transport and enrichment mechanisms of REYs in early diagenetic processes.
ORE GEOLOGY REVIEWS
(2023)
Article
Chemistry, Multidisciplinary
Hang Yin, Josephine Y. Aller, Bradley T. Furman, Robert C. Aller, Qingzhi Zhu
Summary: The metabolic activities of cable bacteria allow them to thrive in sulfidic carbonate muds and play a significant role in sediment carbonate cycling. Cable bacteria utilize subsurface dissolved sulfide as a sole reductant source and do not require the formation of an intermediate suboxic region. Their presence has important implications for the acquisition of phosphorus in carbonate deposits.
Article
Chemistry, Physical
Chengxin Li, Zhuwei Gao, Xinyu Qi, Xintong Han, Zhongxin Liu
Summary: Scientific research on oil-water separation is being conducted worldwide to control water pollution caused by industrial oily wastewater, attracting much attention to green advanced separation materials. In this study, a membrane material with excellent oil-water separation was prepared using stainless steel mesh and metal oxide particles, and its performance was tested and analyzed.
SURFACES AND INTERFACES
(2022)
Article
Chemistry, Physical
Timothy Flack, Samuel A. Jobbins, Salah Eddine Boulfelfel, Stefano Leoni
Summary: This study conducts a comparative analysis of ion mobility in LiMPO4 (M = Mn, Fe) olivine phosphates, focusing on many-particle effects, to identify main diffusion channels and means of interchannel couplings. It highlights the importance of many-particle approaches for reliable mechanistic investigations and benchmarking of battery materials due to the complex nature of diffusion and transport mechanisms.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Chemistry, Physical
Timothy Flack, Samuel A. Jobbins, Salah Eddine Boulfelfel, Stefano Leoni
Summary: In this study, the researchers used a refined version of their finite temperature molecular dynamics shooting approach to analyze ion mobility in LiMPO4 (M = Mn, Fe) olivine phosphates. They identified main diffusion channels and interchannel couplings that impact overall mobility efficiency, supporting the need for many-particle approaches for reliable mechanistic investigations in battery materials.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Geochemistry & Geophysics
A. J. M. Lough, W. B. Homoky, D. P. Connelly, S. A. Comer-Warner, K. Nakamura, M. K. Abyaneh, B. Kaulich, R. A. Mills
Article
Computer Science, Interdisciplinary Applications
Sean Selzer, Amber L. Annett, William B. Homoky
Summary: The Python program presented in this study expedites the correction and uncertainty propagation process for RaDeCC instruments. Validation with real data showed excellent agreement with existing methods, with minor discrepancies attributed to logical improvements in implementation. The program's ability to process large amounts of data files in a short amount of time offers distinct advantages in processing speed and reliable accuracy.
COMPUTERS & GEOSCIENCES
(2021)
Editorial Material
Ecology
Jeroen Ingels, Ann Vanreusel, Ellen Pape, Francesca Pasotti, Lara Macheriotou, Pedro Martinez Arbizu, Martin Vinther Sorensen, Virginia P. Edgcomb, Jyotsna Sharma, Nuria Sanchez, William B. Homoky, Clare Woulds, Daniel Leduc, Andrew J. Gooday, Jan Pawlowski, John R. Dolan, Michaela Schratzberger, Sabine Gollner, Alexandra Schoenle, Hartmut Arndt, Daniela Zeppilli
NATURE ECOLOGY & EVOLUTION
(2021)
Article
Multidisciplinary Sciences
William B. Homoky, Tim M. Conway, Seth G. John, Daniela Konig, FeiFei Deng, Alessandro Tagliabue, Rachel A. Mills
Summary: This study reveals that lithogenic colloid production is the primary mechanism driving iron supply in sediment porewaters in the South Atlantic, which differs from the prevailing understanding. Iron colloids, closely associated with organic carbon abundance, may form a large exchangeable reservoir of organo-mineral Fe colloids in oxic ocean sediments.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2021)
Article
Geochemistry & Geophysics
Allison L. Bryan, Alexander J. Dickson, Fern Dowdall, William B. Homoky, Don Porcelli, Gideon M. Henderson
Summary: The study found that cadmium in continental margin sediments exists mainly in organically bound and sulfide forms, with isotopic compositions lighter compared to seawater. These observations indicate a downward diffusive flux of seawater cadmium and redox-driven removal of cadmium during sulfide precipitation.
EARTH AND PLANETARY SCIENCE LETTERS
(2021)
Article
Environmental Sciences
D. Konig, T. M. Conway, M. J. Ellwood, W. B. Homoky, A. Tagliabue
Summary: Iron isotopes in the ocean are crucial in studying the iron cycle, but the complexity of various external sources and fractionation processes can complicate the interpretation of observations. By incorporating iron isotopes into a global ocean biogeochemical model, research finds that distinct external source endmembers and isotopic fractionation are essential for explaining the distribution of dissolved iron isotopes, with the water column's δFe-56(diss) distribution influenced by regional imbalance of remineralization and abiotic removal processes.
GLOBAL BIOGEOCHEMICAL CYCLES
(2021)
Article
Geochemistry & Geophysics
Fei Wu, Jeremy D. Owens, Christopher R. German, Rachel A. Mills, Sune G. Nielsen
Summary: This study presents the first investigation of V isotope composition in hydrothermal sediments, revealing significant differences compared to non-hydrothermal sediments and open ocean seawater. The study also establishes a mass balance model that assesses the impact of hydrothermal precipitation on the marine elemental and isotopic budget of V, suggesting that hydrothermal input accounts for -13% of the global marine V input.
GEOCHIMICA ET COSMOCHIMICA ACTA
(2022)
Article
Environmental Sciences
Jack Longman, Johan C. Faust, Casey Bryce, William B. Homoky, Christian Maerz
Summary: Bonding organic carbon with reactive iron (OC-Fe-R) enhances its preservation in marine and terrestrial deposits. The proportion of OC stored as OC-Fe-R varies globally, with marine sediments containing roughly 20% and Quaternary terrestrial deposits containing roughly 40% of their OC as OC-Fe-R. This study provides a new assessment of global OC-Fe-R burial rates, estimating the marine sink to be between 31 and 70 Mt C yr(-1) and the terrestrial sink to be between 146 and 917 Mt C yr(-1). The primary settings of OC-Fe-R burial are continental shelves and deltaic/estuarine environments in marine settings, and croplands and grasslands on land.
GLOBAL BIOGEOCHEMICAL CYCLES
(2022)
Article
Geochemistry & Geophysics
Jack Longman, Ann G. Dunlea, Philipp Boening, Martin R. Palmer, Thomas M. Gernon, James McManus, Hayley R. Manners, William B. Homoky, Katharina Pahnke
Summary: This study investigates the geochemical and Fe isotopic composition of tephra layers, sediments, and mixed tephra-sediment samples from the Montserrat region in the Caribbean Sea. The research finds that buried tephras with diagenesis have lighter Fe isotopic compositions compared to fresh tephra. Non-reductive dissolution of tephra is identified as the likely cause for the retention of these light Fe isotopic compositions.
EARTH AND PLANETARY SCIENCE LETTERS
(2023)
Article
Geosciences, Multidisciplinary
Mingyu Zhao, Benjamin J. W. Mills, William B. B. Homoky, Caroline L. L. Peacock
Summary: Photosynthesis produces molecular oxygen, but the burial of organic carbon in sediments is crucial for the accumulation of oxygen in Earth's atmosphere. This study investigates the impact of mineral-organic preservation on the oxygenation of the Earth, showing that iron input into the ocean is an independent control on atmosphere-ocean oxygen levels. The inclusion of mineral-organic preservation in assessments of Earth's carbon cycle is important and breaks the link between productivity and organic carbon burial.
Article
Multidisciplinary Sciences
Oliver W. Moore, Lisa Curti, Clare Woulds, James A. Bradley, Peyman Babakhani, Benjamin J. W. Mills, William B. Homoky, Ke-Qing Xiao, Andrew W. Bray, Ben J. Fisher, Majid Kazemian, Burkhard Kaulich, Andrew W. Dale, Caroline L. Peacock
Summary: The balance between degradation and preservation of sedimentary organic carbon is crucial for global carbon and oxygen cycles. However, the relative importance of different mechanisms and environmental conditions contributing to marine sedimentary organic carbon preservation is still unclear. Recent research suggests that iron and manganese ions and minerals can catalyze the Maillard reaction at a significantly faster rate in continental margin sediments, potentially having a substantial impact on global organic carbon preservation over geological time.
Article
Multidisciplinary Sciences
Alessandro Tagliabue, Kristen N. N. Buck, Laura E. E. Sofen, Benjamin S. S. Twining, Olivier Aumont, Philip W. W. Boyd, Salvatore Caprara, William B. B. Homoky, Rod Johnson, Daniela Konig, Daniel C. C. Ohnemus, Bettina Sohst, Peter Sedwick
Summary: Iron is important in regulating the ocean carbon cycle, with organic ligands playing a crucial role in stabilizing dissolved iron concentrations. However, the role of authigenic iron phases and the inconsistencies observed in dissolved iron cycling challenge the primary control of ligands. Through a study in the Bermuda Atlantic Time-series Study (BATS) region, it was found that upper-ocean dissolved iron dynamics are decoupled from ligands, indicating the need for a mechanism that allows dissolved iron to escape ligand stabilization and form a reservoir of settling iron particles. When this mechanism was implemented in a global-scale biogeochemical model, it successfully reproduced seasonal iron-cycle dynamics and global datasets where previous models failed.
Article
Environmental Sciences
Alastair J. M. Lough, Douglas P. Connelly, William B. Homoky, Jeffrey A. Hawkes, Valerie Chavagnac, Alain Castillo, Majid Kazemian, Ko-ichi Nakamura, Tohru Araki, Burkhard Kaulich, Rachel A. Mills
FRONTIERS IN MARINE SCIENCE
(2019)
Article
Environmental Sciences
Sarah Fielding, Jonathan T. Copley, Rachel A. Mills
FRONTIERS IN MARINE SCIENCE
(2019)
Article
Geochemistry & Geophysics
Xinze Lu, Geoffrey J. Gilleaudeau, Brian Kendall
Summary: The Late Ordovician mass extinction is the first major extinction event in the Phanerozoic, but the reasons for the decline in global biodiversity before the extinction are not well understood.
GEOCHIMICA ET COSMOCHIMICA ACTA
(2024)
Article
Geochemistry & Geophysics
Junyao Kang, Daniel D. Gregory, Benjamin Gill, Shiqiang Huang, Changxin Lai, Zhaoshan Chang, Huan Cui, Ivan Belousov, Shuhai Xiao
Summary: Sedimentary pyrite is an important geological archive, but it can be altered by diagenetic and hydrothermal processes. This study successfully trained machine learning algorithms to distinguish pyrite origins using trace element data. The approach was validated and applied to identify the origins of pyrite in two sedimentary successions in South China.
GEOCHIMICA ET COSMOCHIMICA ACTA
(2024)