Article
Geochemistry & Geophysics
Urmi Ghosh, Dewashish Upadhyay, Kumar Abhinay, Biswajit Mishra
Summary: The study in western India's Proterozoic tungsten belts of Balda and Motiya reveals that the tungsten mineralization process may involve hydrothermal fluid derived from granites rich in Li, Mn, Zn, and Sn, indicating an important role of biotite dissolution and fluid-rock interaction. The chemistry and B-isotope composition of tourmalines suggest that the W-bearing hydrothermal fluid interacted with nearby pelitic rocks during the precipitation of wolframite and tourmaline.
Article
Geochemistry & Geophysics
Renata Copjakova, Jiri Prokop, Milan Novak, Zdenek Losos, Petr Gadas, Radek Skoda, Marketa Hola
Summary: The hydrothermal alteration of primary tourmaline and associated minerals in pegmatitic rocks from the Moldanubian Zone, Czech Republic was examined, showing a wide spectrum of minerals replacing tourmaline and presenting idealized replacement reactions. The study suggests an evolution of PT conditions during tourmaline alteration from high temperatures to lower temperatures.
Article
Geochemistry & Geophysics
Wei Li, Shuyun Cao, Eizo Nakamura, Tsutomu Ota, Zhong Liu, Yanlong Dong, Tak Kunihiro
Summary: Tourmalines in the Laojunshan metamorphic massif exhibit variable structures and compositions, indicating the influence of multi-stage fluid influx and deformation on the formation of tourmalines.
Article
Geology
Zhuang Zhao, Xiaoyong Yang, Tuyan Zhang, Youyue Lu, Wanying Li, Zunzun Zhang
Summary: This study investigates the magmatic-fluid evolution and ore-forming processes of the Baishaziling greisen-type tin deposit by conducting detailed petrography and geochemical studies of different types of tourmalines. The results suggest that the mechanism of Sn enrichment and deposition may be related to fluid-rock interaction and fluid mixing.
ORE GEOLOGY REVIEWS
(2022)
Article
Chemistry, Physical
Natalia Anna Wojcik, Polina Sinitsyna, Sharafat Ali, Leena Hupa, Bo Jonson
Summary: The in vitro dissolution, ion release, and pH changes of oxynitride glasses and glass-ceramics doped with Mg, Si, and Nb in simulated body fluid were studied. It was found that the incorporation of nitrogen significantly influenced the dissolution rate, while the incorporation of niobate increased the mass loss. Additionally, an increase in nitrogen content was observed to correlate with an increase in the pH of the SBF.
Article
Geochemistry & Geophysics
Pranjit Hazarika, Dewashish Upadhyay, Biswajit Mishra, Pritom Borah, Kumar Abhinay
Summary: The source of mineralizing fluid in Archean greenstone-hosted orogenic gold deposits is widely debated, with geochemical and isotope data pointing to a complex formation process involving multiple fluid sources, leading to large variations in B-isotope composition of tourmaline. Modeling of boron release and associated fractionation during metamorphic dehydration of greenstone rocks suggest distinct delta B-11 distributions from different fluid sources, highlighting the importance of understanding metamorphic processes in evaluating fluid sources for orogenic gold deposits.
GEOCHIMICA ET COSMOCHIMICA ACTA
(2021)
Article
Thermodynamics
Jingchun Huang, Zhenqi Wang, Yu Qiao, Bo Wang, Yun Yu, Minghou Xu
Summary: Temperature significantly affects the transformation of nitrogen during sludge hydrothermal carbonization, with different distributions of nitrogen in different products at different temperatures. The transformation pathways of protein-N and amino acid species are also influenced by temperature and the addition of CaAc and NaAc.
PROCEEDINGS OF THE COMBUSTION INSTITUTE
(2021)
Article
Food Science & Technology
A. Lopez-Lopez, J. M. Moreno-Baquero, A. Garrido-Fernandez
Summary: The mineral equilibrium between olive flesh and surrounding brines was studied using a pseudo-distribution coefficient, K-d. It was found that Na and K had lower concentrations in the flesh compared to brine, while Ca had higher concentrations. Additionally, Ca may form complexes with soluble olive flesh components. Regression analysis showed that the concentrations of Na, K, and Ca in the flesh could be estimated based on their concentrations in brine.
LWT-FOOD SCIENCE AND TECHNOLOGY
(2023)
Article
Geochemistry & Geophysics
Matthieu Harlaux, Kalin Kouzmanov, Stefano Gialli, Katharina Marger, Anne-Sophie Bouvier, Lukas P. Baumgartner, Andrea Rielli, Andrea Dini, Alain Chauvet, Miroslav Kalinaj, Lluis Fontbote
Summary: The study on oxygen and boron isotopes in tourmaline from the San Rafael Sn (-Cu) deposit reveals the major fluid processes at the magmatic-hydrothermal transition leading to cassiterite precipitation. Variations in isotopic composition indicate fluid mixing of different sources during different stages, influencing the deposition of cassiterite. This study demonstrates the effectiveness of in situ isotopic analysis in understanding fluid processes in dynamic magmatic-hydrothermal environments.
EARTH AND PLANETARY SCIENCE LETTERS
(2021)
Article
Chemistry, Applied
Takahiro Ohkubo, Akio Yamazaki, Yuta Fukatsu, Yukio Tachi
Summary: This study investigated pore distributions in water-saturated Ca-montmorillonite under various dry densities and porewater salinity conditions using H-1 nuclear magnetic resonance measurements. It was found that density is the main factor affecting pore distribution in compacted Ca and Na-montmorillonite, while the effect of porewater salinity and interlayer cations is relatively smaller. The established method based on NMR relaxometry is expected to provide structural parameters for realistic modeling of mass transport in water-saturated compacted clay.
MICROPOROUS AND MESOPOROUS MATERIALS
(2021)
Article
Geochemistry & Geophysics
Rong Yin, Xiao-Long Huang, Ru-Cheng Wang, Gang-Jian Wei, Yi-Gang Xu, Yu Wang, Xiao-Ming Sun, Le Zhang, Xiao-Ping Xia
Summary: LCT-type pegmatites are characterized by zoning texture and extreme enrichment of rare-metals. Tourmaline is ubiquitously present in all textural zones and exhibits a range of compositions. The decreasing δ11B values of tourmalines from outer to inner zones are attributed to the separation of an immiscible fluid phase. The occurrence of hydrothermal tourmaline indicates the exsolution of fluids, facilitating the precipitation of rare-metal minerals. Fractional crystallization and exsolved fluids play significant roles in the formation of internal zones and rare-metal mineralization in LCT-type pegmatites.
Article
Materials Science, Ceramics
Zsolt Kovacs, Margit Fabian, Noemi Szasz, Inna Szekacs, Viktoria Kovacs Kis
Summary: A wide range of bioactive glasses with excellent degradability and bioactivity in the human body were synthesized and tested for bioactivity in simulated body fluid. A novel quantitative assessment method for bioactive layer formation was proposed based on nanoindentation tests.
JOURNAL OF NON-CRYSTALLINE SOLIDS
(2022)
Article
Engineering, Electrical & Electronic
Gemeng Huang, Maorong Feng, Chen Yang, Shengmin Li, Ming Ma, Song Xia, Shiji Fan, Zhenrong Li
Summary: The liquid epitaxial growth process on the HVPE-GaN seed of GaN crystal using the Na-Li-Ca flux method was investigated. The phase structure and morphology of as-grown GaN crystals were characterized using X-ray diffraction (XRD) and scanning electron microscope (SEM), respectively. It was observed that as the growth time increased, the growth mode shifted from an unstable cellular growth surface morphology to a typical hexagonal layered growth morphology. The thickness of the crystal also decreased from the gas-liquid interface to the bottom of the crucible. The promotion of N dissolving and GaN growth unit diffusion were identified as key factors in achieving near-equilibrium growth mode for the entire crystal plate in the Na-flux method.
MATERIALS SCIENCE IN SEMICONDUCTOR PROCESSING
(2022)
Article
Chemistry, Multidisciplinary
Yuichi Morishita
Summary: The oxygen isotope ratios of minerals play a crucial role in estimating the formation temperature of hydrothermal deposits. Calcite is commonly found in mining districts and its isotopic equilibrium with fluids depends on the fluid's oxygen isotope ratio and the formation temperature. The isotope ratios of calcite are determined by measuring the isotope ratios of CO2 produced through reaction with phosphoric acid. The study determined the oxygen isotope fractionation in CO2 during the reaction of calcite with phosphoric acid at temperatures ranging from 1°C to 150°C, and discussed the equilibrium vs. kinetics issue in isotopic reactions based on previous studies.
APPLIED SCIENCES-BASEL
(2023)
Article
Mineralogy
Cristian Biagioni, Ferdinando Bosi, Daniela Mauro, Henrik Skogby, Andrea Dini, Federica Zaccarini
Summary: The new tourmaline supergroup mineral dutrowite has been discovered in Italy. It occurs in a rhyolite outcrop and is closely associated with oxy-dravite. Dutrowite has a trigonal crystal structure with a specific chemical formula. Its occurrence is related to the late-stage evolution of the rhyolite.
EUROPEAN JOURNAL OF MINERALOGY
(2023)
