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1

Tian, Zhen, Tomáš Magna, James M. D. Day, Klaus Mezger, Erik E. Scherer, Katharina Lodders, Remco C. Hin, Piers Koefoed, Hannah Bloom e Kun Wang. "Potassium isotope composition of Mars reveals a mechanism of planetary volatile retention". Proceedings of the National Academy of Sciences 118, n. 39 (20 settembre 2021): e2101155118. http://dx.doi.org/10.1073/pnas.2101155118.

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The abundances of water and highly to moderately volatile elements in planets are considered critical to mantle convection, surface evolution processes, and habitability. From the first flyby space probes to the more recent “Perseverance” and “Tianwen-1” missions, “follow the water,” and, more broadly, “volatiles,” has been one of the key themes of martian exploration. Ratios of volatiles relative to refractory elements (e.g., K/Th, Rb/Sr) are consistent with a higher volatile content for Mars than for Earth, despite the contrasting present-day surface conditions of those bodies. This study presents K isotope data from a spectrum of martian lithologies as an isotopic tracer for comparing the inventories of highly and moderately volatile elements and compounds of planetary bodies. Here, we show that meteorites from Mars have systematically heavier K isotopic compositions than the bulk silicate Earth, implying a greater loss of K from Mars than from Earth. The average “bulk silicate” δ41K values of Earth, Moon, Mars, and the asteroid 4-Vesta correlate with surface gravity, the Mn/Na “volatility” ratio, and most notably, bulk planet H2O abundance. These relationships indicate that planetary volatile abundances result from variable volatile loss during accretionary growth in which larger mass bodies preferentially retain volatile elements over lower mass objects. There is likely a threshold on the size requirements of rocky (exo)planets to retain enough H2O to enable habitability and plate tectonics, with mass exceeding that of Mars.
2

Day, James M. D., Frédéric Moynier e Charles K. Shearer. "Late-stage magmatic outgassing from a volatile-depleted Moon". Proceedings of the National Academy of Sciences 114, n. 36 (21 agosto 2017): 9547–51. http://dx.doi.org/10.1073/pnas.1708236114.

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The abundance of volatile elements and compounds, such as zinc, potassium, chlorine, and water, provide key evidence for how Earth and the Moon formed and evolved. Currently, evidence exists for a Moon depleted in volatile elements, as well as reservoirs within the Moon with volatile abundances like Earth’s depleted upper mantle. Volatile depletion is consistent with catastrophic formation, such as a giant impact, whereas a Moon with Earth-like volatile abundances suggests preservation of these volatiles, or addition through late accretion. We show, using the “Rusty Rock” impact melt breccia, 66095, that volatile enrichment on the lunar surface occurred through vapor condensation. Isotopically light Zn (δ66Zn = −13.7‰), heavy Cl (δ37Cl = +15‰), and high U/Pb supports the origin of condensates from a volatile-poor internal source formed during thermomagmatic evolution of the Moon, with long-term depletion in incompatible Cl and Pb, and lesser depletion of more-compatible Zn. Leaching experiments on mare basalt 14053 demonstrate that isotopically light Zn condensates also occur on some mare basalts after their crystallization, confirming a volatile-depleted lunar interior source with homogeneous δ66Zn ≈ +1.4‰. Our results show that much of the lunar interior must be significantly depleted in volatile elements and compounds and that volatile-rich rocks on the lunar surface formed through vapor condensation. Volatiles detected by remote sensing on the surface of the Moon likely have a partially condensate origin from its interior.
3

Zhang, Youxue. "Review of melt inclusions in lunar rocks: constraints on melt and mantle composition and magmatic processes". European Journal of Mineralogy 36, n. 1 (26 gennaio 2024): 123–38. http://dx.doi.org/10.5194/ejm-36-123-2024.

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Abstract. Mineral-hosted melt inclusions provide a window into magmatic processes and pre-eruptive liquid compositions. Because melt inclusions are small (typically < 100 µm), the study of lunar melt inclusions is enabled by advancements of microbeam instrumental techniques. In the 1970s immediately following the Apollo and Luna missions, major and minor oxide concentrations of lunar melt inclusions were measured using electron microprobes. The data were used to understand magma evolution, and they revealed the immiscibility of two silicate liquids in the late stage of lunar magma evolution. More recently, the development of secondary ion mass spectrometry as well as laser ablation–inductively coupled plasma–mass spectrometry has enabled the measurement of key volatile elements and other trace elements in lunar melt inclusions, down to about the 0.1 ppm level. The applications of these instruments have ushered in a new wave of lunar melt inclusion studies. Recent advances have gone hand in hand with improved understanding of post-entrapment loss of volatiles. These studies have provided deep insights into pre-eruptive volatiles in lunar basalts, the abundance of volatiles in the lunar mantle, the isotopic ratios of some volatile elements, and the partition of trace elements between host olivine and melt inclusions. The recent studies of lunar melt inclusions have played a critical role in establishing a new paradigm of a fairly wet Moon with about 100 ppm H2O in the bulk silicate Moon (rather than a “bone-dry” Moon) and have been instrumental in developing an improved understanding of the origin and evolution of the Moon.
4

Chen, Zuxing, Landry Soh Tamehe, Haiyan Qi, Yuxiang Zhang, Zhigang Zeng e Mingjiang Cai. "Using Apatite to Track Volatile Evolution in the Shallow Magma Chamber below the Yonaguni Knoll IV Hydrothermal Field in the Southwestern Okinawa Trough". Journal of Marine Science and Engineering 11, n. 3 (9 marzo 2023): 583. http://dx.doi.org/10.3390/jmse11030583.

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The Yonaguni Knoll IV is an active seafloor hydrothermal system associated with submarine silicic volcanism located in the “cross back-arc volcanic trail” (CBVT) in the southwestern Okinawa Trough. However, the behavior of volatiles during magmatic differentiation in the shallow silicic magma chamber is unclear. Here, the volatile contents of apatite inclusions trapped in different phenocrysts (orthopyroxene and amphibole) and microphenocrysts in the rhyolite from the Yonaguni Knoll IV hydrothermal field were analyzed by using electron microprobe analysis, which aims to track the behavior of volatiles in the shallow magma chamber. Notably, the ‘texturally constrained’ apatites showed a decreasing trend of XCl/XOH and XF/XCl ratios. Based on the geochemical analyses in combination with thermodynamic modeling, we found that the studied apatites were consistent with the mode of volatile-undersaturated crystallization. Therefore, volatiles were not saturated in the early stage of magmatic differentiation in the shallow rhyolitic magma chamber, and consequently, the metal elements were retained in the rhyolitic melt and partitioned into crystalline magmatic sulfides. Additionally, previous studies suggested that the shallow rhyolitic magma chamber was long-lived and periodically replenished by mafic magma. The injection of volatile-rich and oxidized subduction-related mafic magmas can supply abundant volatiles and dissolve magmatic sulfide in the shallow magma chamber. These processes are important for the later-stage of volatile exsolution, while the forming metal-rich magmatic fluids contribute to the overlying Yonaguni Knoll IV hydrothermal system.
5

Miller, Johanna L. "Krypton isotopes tell the early story of Earth’s life-giving elements". Physics Today 75, n. 3 (1 marzo 2022): 16–18. http://dx.doi.org/10.1063/pt.3.4956.

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Liu, Xuena, Jinghua Guo, Zijing Chen, Kun Xu e Kang Xu. "Detection of Volatile Compounds and Their Contribution to the Nutritional Quality of Chinese and Japanese Welsh Onions (Allium fistulosum L.)". Horticulturae 10, n. 5 (26 aprile 2024): 446. http://dx.doi.org/10.3390/horticulturae10050446.

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Allium vegetables attract attention for their flavor and aroma in Asia, especially in China and Japan. The aim of this experiment was to uncover the differences in the unique flavor compounds of two Welsh onions that are typical cultivars in China and Japan (‘Zhangqiu’ and ‘Tenko’). Chemical methods and solid-phase microextraction–gas chromatography-mass spectrometry were performed to determine the nutritional quality and quantity of volatile compounds of various organs of Welsh onions. The results show that a total of 30, 37, and 28 compounds were detected in the roots, pseudostem, and leaves of ‘Zhangqiu’, respectively, while 21, 27, and 20 compounds were detected in the corresponding organs of ‘Tenko’. The distribution of sulfur compounds in the roots, pseudostem, and leaves of ‘Zhangqiu’ accounted for 72%, 83%, and 26% of the total content, while those of ‘Tenko’ accounted for 55%, 84%, and 57%, respectively. Aldehydes are the second largest class of volatiles in Welsh onions. The distribution of aldehydes in the leaves was notably different: 52% and 27% in ‘Zhangqiu’ and ‘Tenko’, respectively. The contribution of S to the volatile substances was outstanding, and through forward selection, it was found that P, Ca, and Mg contribute to the volatile substances of Welsh onions. The above results indicate that the different genotypes of Welsh onions have various flavors, and mineral elements contribute variously to these flavors. Calcium could be a new topic of interest for our subsequent research on elements and volatiles.
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Degruyter, Wim, Andrea Parmigiani, Christian Huber e Olivier Bachmann. "How do volatiles escape their shallow magmatic hearth?" Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 377, n. 2139 (7 gennaio 2019): 20180017. http://dx.doi.org/10.1098/rsta.2018.0017.

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Only a small fraction (approx. 1–20%) of magmas generated in the mantle erupt at the surface. While volcanic eruptions are typically considered as the main exhaust pipes for volatile elements to escape into the atmosphere, the contribution of magma reservoirs crystallizing in the crust is likely to dominate the volatile transfer from depth to the surface. Here, we use multiscale physical modelling to identify and quantify the main mechanisms of gas escape from crystallizing magma bodies. We show that most of the outgassing occurs at intermediate to high crystal fraction, when the system has reached a mature mush state. It is particularly true for shallow volatile-rich systems that tend to exsolve volatiles through second boiling, leading to efficient construction of gas channels as soon as the crystallinity reaches approximately 40–50 vol.%. We, therefore, argue that estimates of volatile budgets based on volcanic activity may be misleading because they tend to significantly underestimate the magmatic volatile flux and can provide biased volatile compositions. Recognition of the compositional signature and volumetric dominance of intrusive outgassing is, therefore, necessary to build robust models of volatile recycling between the mantle and the surface. This article is part of the Theo Murphy meeting issue ‘Magma reservoir architecture and dynamics’.
8

Day, James M. D., e Frederic Moynier. "Evaporative fractionation of volatile stable isotopes and their bearing on the origin of the Moon". Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 372, n. 2024 (13 settembre 2014): 20130259. http://dx.doi.org/10.1098/rsta.2013.0259.

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The Moon is depleted in volatile elements relative to the Earth and Mars. Low abundances of volatile elements, fractionated stable isotope ratios of S, Cl, K and Zn, high μ ( 238 U/ 204 Pb) and long-term Rb/Sr depletion are distinguishing features of the Moon, relative to the Earth. These geochemical characteristics indicate both inheritance of volatile-depleted materials that formed the Moon and planets and subsequent evaporative loss of volatile elements that occurred during lunar formation and differentiation. Models of volatile loss through localized eruptive degassing are not consistent with the available S, Cl, Zn and K isotopes and abundance data for the Moon. The most probable cause of volatile depletion is global-scale evaporation resulting from a giant impact or a magma ocean phase where inefficient volatile loss during magmatic convection led to the present distribution of volatile elements within mantle and crustal reservoirs. Problems exist for models of planetary volatile depletion following giant impact. Most critically, in this model, the volatile loss requires preferential delivery and retention of late-accreted volatiles to the Earth compared with the Moon. Different proportions of late-accreted mass are computed to explain present-day distributions of volatile and moderately volatile elements (e.g. Pb, Zn; 5 to >10%) relative to highly siderophile elements (approx. 0.5%) for the Earth. Models of early magma ocean phases may be more effective in explaining the volatile loss. Basaltic materials (e.g. eucrites and angrites) from highly differentiated airless asteroids are volatile-depleted, like the Moon, whereas the Earth and Mars have proportionally greater volatile contents. Parent-body size and the existence of early atmospheres are therefore likely to represent fundamental controls on planetary volatile retention or loss.
9

Nunes, Ana R., Ana C. Gonçalves, Edgar Pinto, Filipa Amaro, José D. Flores-Félix, Agostinho Almeida, Paula Guedes de Pinho, Amílcar Falcão, Gilberto Alves e Luís R. Silva. "Mineral Content and Volatile Profiling of Prunus avium L. (Sweet Cherry) By-Products from Fundão Region (Portugal)". Foods 11, n. 5 (4 marzo 2022): 751. http://dx.doi.org/10.3390/foods11050751.

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Large amounts of Prunus avium L. by-products result from sweet cherry production and processing. This work aimed to evaluate the mineral content and volatile profiling of the cherry stems, leaves, and flowers of the Saco cultivar collected from the Fundão region (Portugal). A total of 18 minerals were determined by ICP-MS, namely 8 essential and 10 non-essential elements. Phosphorus (P) was the most abundant mineral, while lithium (Li) was detected in trace amounts. Three different preparations were used in this work to determine volatiles: hydroethanolic extracts, crude extracts, and aqueous infusions. A total of 117 volatile compounds were identified using HS-SPME/GC-MS, distributed among different chemical classes: 31 aldehydes, 14 alcohols, 16 ketones, 30 esters, 4 acids, 4 monoterpenes, 3 norisoprenoids, 4 hydrocarbons, 7 heterocyclics, 1 lactone, 1 phenol, and 2 phenylpropenes. Benzaldehyde, 4-methyl-benzaldehyde, hexanal, lilac aldehyde, and 6-methyl-5-hepten-2-one were the major volatile compounds. Differences in the types of volatiles and their respective amounts in the different extracts were found. This is the first study that describes the mineral and volatile composition of Portuguese sweet cherry by-products, demonstrating that they could have great potential as nutraceutical ingredients and natural flavoring agents to be used in the pharmaceutical, cosmetic, and food industries.
10

Marty, Bernard. "Origins and Early Evolution of the Atmosphere and the Oceans". Geochemical Perspectives 9, n. 2 (ottobre 2020): 135–313. http://dx.doi.org/10.7185/geochempersp.9.2.

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My journey in science began with the study of volcanic gases, sparking an interest in the origin, and ultimate fate, of the volatile elements in the interior of our planet. How did these elements, so crucial to life and our surface environment, come to be sequestered within the deepest regions of the Earth, and what can they tell us about the processes occurring there? My approach has been to establish geochemical links between the noble gases, physical tracers par excellence, with major volatile elements of environmental importance, such as water, carbon and nitrogen, in mantle-derived rocks and gases. From these analyses we have learned that the Earth is relatively depleted in volatile elements when compared to its potential cosmochemical ancestors (e.g., ~2 ppm nitrogen compared to several hundreds of ppm in primitive meteorites) and that natural fluxes of carbon are two orders of magnitude lower than those emitted by current anthropogenic activity. Further insights into the origin of terrestrial volatiles have come from space missions that documented the composition of the proto-solar nebula and the outer solar system. The consensus behind the origin of the atmosphere and the oceans is evolving constantly, although recently a general picture has started to emerge. At the dawn of the solar system, the volatile-forming elements (H, C, N, noble gases) that form the majority of our atmosphere and oceans were trapped in solid dusty phases (mostly in ice beyond the snowline and organics everywhere). These phases condensed from the proto-solar nebula gas, and/or were inherited from the interstellar medium. These accreted together within the next few million years to form the first planetesimals, some of which underwent differentiation very early on. The isotopic signatures of volatiles were also fixed very early and may even have preceded the first episodes of condensation and accretion. Throughout the accretion of the Earth, volatile elements were delivered by material from both the inner (dry, volatile-poor) and outer (volatile-rich) solar system. This delivery was concomitant with the metals and silicates that form the bulk of the planet. The contribution of bodies that formed in the far outer solar system, a region now populated by comets, is likely to have been very limited. In that sense, volatile elements were contributed continuously throughout Earth’s accretion from inner solar system reservoirs, which also provided the silicates and metal building blocks of the inner planets. Following accretion, it likely took a few hundred million years for the Earth’s atmosphere and oceans to stabilise. Luckily, we have been able to access a compositional record of the early atmosphere and oceans through the analysis of palaeo-atmospheric fluids trapped in Archean hydrothermal quartz. From these analyses, it appears that the surface reservoirs of the Earth evolved due to interactions between the early Sun and the top of the atmosphere, as well as the development of an early biosphere that progressively altered its chemistry.
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Ivić, Ivana, Mirela Kopjar, Jasmina Obhođaš, Andrija Vinković, Dubravko Pichler, Josip Mesić e Anita Pichler. "Concentration with Nanofiltration of Red Wine Cabernet Sauvignon Produced from Conventionally and Ecologically Grown Grapes: Effect on Volatile Compounds and Chemical Composition". Membranes 11, n. 5 (27 aprile 2021): 320. http://dx.doi.org/10.3390/membranes11050320.

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Ecological viticulture represent an upward trend in many countries. Unlike conventional viticulture, it avoids the use of chemical fertilizers and other additives, minimizing the impact of chemicals on the environment and human health. The aim of this study was to investigate the influence of nanofiltration (NF) process on volatiles and chemical composition of conventional and ecological Cabernet Sauvignon red wine. The NF process was conducted on laboratory Alfa Laval LabUnit M20 (De Danske Sukkerfabrikker, Nakskov, Denmark) equipped with six NF M20 membranes in a plate module, at two temperature regimes, with and without cooling and four pressures (2.5, 3.5, 4.5 and 5.5 MPa). Different processing parameters significantly influenced the permeate flux which increased when higher pressure was applied. In initial wines and obtained retentates, volatile compounds, chemical composition and elements concentration were determined. The results showed that the higher pressure and retentate cooling was more favourable for total volatiles retention than lower pressure and higher temperature. Individual compound retention depended on its chemical properties, applied processing parameters and wine composition. Nanofiltration process resulted in lower concentrations of ethanol, acetic acid (>50%), 4-ethylphenol and 4-ethylguaiacol (>90%). Different composition of initial feed (conventional and ecological wine) had an important impact on retention of elements.
12

Mahan, Brandon, Frédéric Moynier, Julien Siebert, Bleuenn Gueguen, Arnaud Agranier, Emily A. Pringle, Jean Bollard, James N. Connelly e Martin Bizzarro. "Volatile element evolution of chondrules through time". Proceedings of the National Academy of Sciences 115, n. 34 (6 agosto 2018): 8547–52. http://dx.doi.org/10.1073/pnas.1807263115.

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Chondrites and their main components, chondrules, are our guides into the evolution of the Solar System. Investigating the history of chondrules, including their volatile element history and the prevailing conditions of their formation, has implications not only for the understanding of chondrule formation and evolution but for that of larger bodies such as the terrestrial planets. Here we have determined the bulk chemical composition—rare earth, refractory, main group, and volatile element contents—of a suite of chondrules previously dated using the Pb−Pb system. The volatile element contents of chondrules increase with time from ∼1 My after Solar System formation, likely the result of mixing with a volatile-enriched component during chondrule recycling. Variations in the Mn/Na ratios signify changes in redox conditions over time, suggestive of decoupled oxygen and volatile element fugacities, and indicating a decrease in oxygen fugacity and a relative increase in the fugacities of in-fluxing volatiles with time. Within the context of terrestrial planet formation via pebble accretion, these observations corroborate the early formation of Mars under relatively oxidizing conditions and the protracted growth of Earth under more reducing conditions, and further suggest that water and volatile elements in the inner Solar System may not have arrived pairwise.
13

Grewal, Damanveer S., Rajdeep Dasgupta, Chenguang Sun, Kyusei Tsuno e Gelu Costin. "Delivery of carbon, nitrogen, and sulfur to the silicate Earth by a giant impact". Science Advances 5, n. 1 (gennaio 2019): eaau3669. http://dx.doi.org/10.1126/sciadv.aau3669.

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Earth’s status as the only life-sustaining planet is a result of the timing and delivery mechanism of carbon (C), nitrogen (N), sulfur (S), and hydrogen (H). On the basis of their isotopic signatures, terrestrial volatiles are thought to have derived from carbonaceous chondrites, while the isotopic compositions of nonvolatile major and trace elements suggest that enstatite chondrite–like materials are the primary building blocks of Earth. However, the C/N ratio of the bulk silicate Earth (BSE) is superchondritic, which rules out volatile delivery by a chondritic late veneer. In addition, if delivered during the main phase of Earth’s accretion, then, owing to the greater siderophile (metal loving) nature of C relative to N, core formation should have left behind a subchondritic C/N ratio in the BSE. Here, we present high pressure-temperature experiments to constrain the fate of mixed C-N-S volatiles during core-mantle segregation in the planetary embryo magma oceans and show that C becomes much less siderophile in N-bearing and S-rich alloys, while the siderophile character of N remains largely unaffected in the presence of S. Using the new data and inverse Monte Carlo simulations, we show that the impact of a Mars-sized planet, having minimal contributions from carbonaceous chondrite-like material and coinciding with the Moon-forming event, can be the source of major volatiles in the BSE.
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Sørensen, Henning. "The agpaitic rocks - an overview". Mineralogical Magazine 61, n. 407 (agosto 1997): 485–98. http://dx.doi.org/10.1180/minmag.1997.061.407.02.

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AbstractIt is now generally agreed that the term ‘agpaitic’ should be restricted to peralkaline nepheline syenites (and phonolites) containing minerals such as eudialyte and rinkite, that is complex silicates of Zr, Ti, the rare earth elements (REE), and F and other volatiles. There are, however, cases of transition into more common types of nepheline syenites containing zircon, titanite, ilmenite, etc.The agpaitic rocks are characterized by extremely high contents of rare elements such as Li, Be, Nb, Ta,REE, Zr, Th, etc. and of volatiles, first of all F and Cl. This gives rise to a wealth of mineral species, more than 500 in the Lovozero and Khibina complexes of the Kola peninsula, about 250 in Mont Saint-Hilaire, Quebec, Canada, and about 200 in the type locality, the Ilímaussaq complex, South Greenland.These rocks have very long melting intervals and solidus temperatures as low as 500 to 400°C. They are accompanied by a gas phase rich in methane and other hydrocarbons and most probably also by sodium-rich fluids as indicated by the presence of minerals such as ussingite (NaAlSi3O8·NaOH) and villiaumite (NaF) and of pegmatites and hydrothermal veins rich in sodium and rare and volatile elements.Agpaitic nepheline syenites are considered to have been formed by consolidation of melts oversaturated in alkalis, especially sodium, under conditions preventing the volatiles from escaping. These melts have been derived by extreme fractionation processes in alkali basaltic or nephelinitic magmas. The main stage of crystallization of the melts is characterized by minerals such as nepheline (sometimes also sodalite), alkali feldspars, arfvedsonite, aegirine and eudialyte, but the most highly developed, hyperagpaitic lujavrites of the Ilímaussaq complex have been formed from melts with extreme concentrations of sodium and volatiles resulting in the formation of naujakasite instead of nepheline, ussingite instead of sodalite and alkali feldspars, and steenstrupine instead of eudialyte. During the late stages of crystallization, sodium-rich fluids are the cause of late- and postmagmatic alteration and of the formation of hydrothermal mineralizations. The late stages are characterized by water-soluble sodium-rich minerals of which more than 80 have been found in the Khibina and Lovozero complexes.
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Palme, H., G. Kurat, B. Spettel e A. Burghele. "Chemical Composition of an Unusual Xenolith of the Allende Meteorite". Zeitschrift für Naturforschung A 44, n. 10 (1 ottobre 1989): 1005–14. http://dx.doi.org/10.1515/zna-1989-1012.

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Abstract The chemical composition of an unusual xenolith (All-AF) from the Allende meteorite was determined by neutron activation and x-ray fluorescence analyses. The xenolith is similar in bulk composition to Allende, but has large excesses in some moderately volatile trace elements, such as Na, K, Au, Sb etc. Some of these elements show considerable variations in other components of Allende, suggesting inhomogeneous distribution in Allende. However, elements of higher volatility, such as Zn and Se have concentrations typical of bulk Allende and other type 3 carbonaceous chondrites. Therefore, All-AF must have formed from the same reservoir as bulk Allende.All-AF has uniform grain size and does not, and did never, contain chondrules. The low content of volatile elements, therefore cannot be ascribed to loss of volatiles during the chondrule forming process. It is a characteristic of the Allende reservoir. The chemical composition of related dark inclusions (DIs) in Allende is different from All-AF. Dark inclusions may have formed by separation of fine grained material in the early solar nebula while All-AF resembles bulk Allende material that was never subject to chondrule formation. Both, dark inclusions and All-AF have oxygen isotopic compositions which plot at the upper end of the δ18O vs. δ17O correlation, suggesting extensive oxygen exchange with ambient gas.
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Gaggiotti, Sara, Flavio Della Pelle, Marcello Mascini, Angelo Cichelli e Dario Compagnone. "Peptides, DNA and MIPs in Gas Sensing. From the Realization of the Sensors to Sample Analysis". Sensors 20, n. 16 (8 agosto 2020): 4433. http://dx.doi.org/10.3390/s20164433.

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Detection and monitoring of volatiles is a challenging and fascinating issue in environmental analysis, agriculture and food quality, process control in industry, as well as in ‘point of care’ diagnostics. Gas chromatographic approaches remain the reference method for the analysis of volatile organic compounds (VOCs); however, gas sensors (GSs), with their advantages of low cost and no or very little sample preparation, have become a reality. Gas sensors can be used singularly or in array format (e.g., e-noses); coupling data output with multivariate statical treatment allows un-target analysis of samples headspace. Within this frame, the use of new binding elements as recognition/interaction elements in gas sensing is a challenging hot-topic that allowed unexpected advancement. In this review, the latest development of gas sensors and gas sensor arrays, realized using peptides, molecularly imprinted polymers and DNA is reported. This work is focused on the description of the strategies used for the GSs development, the sensing elements function, the sensors array set-up, and the application in real cases.
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Chernysheva, E. A., e D. V. Eroshenko. "Regularities in variations of the pume volcanics composition in the Southern Atlantic and at the African plate". Океанология 59, n. 2 (9 giugno 2019): 271–81. http://dx.doi.org/10.31857/s0030-1574592271-281.

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The action of the African Superplume provided input and accumulation of the volatile, alkaline and some others elements at the base of continental lithosphere. Transformation and interaction of these components with mantle peridotites took place under the African continental plate of the great thickness. Generation of low silica and rich in CO2 melts occurs at the great depth: this is the family of kimberlites, melilitites and carbonatites. At the shallower levels of the lithospheric plate the melts of basalts originated; they are more rich in SiO2 and poor in volatiles. The origin of deep generated volcanics was controlled by the pressure of CO2 in the fluids. The melting of basalts is connected mainly with tectonic position.
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Umar, Akrajas Ali, Muhamad Mat Salleh e Muhammad Yahaya. "Optical Electronic Nose Based on Fe (III) Complex of Porphyrins Films for Detection of Volatile Compounds". Key Engineering Materials 495 (novembre 2011): 75–78. http://dx.doi.org/10.4028/www.scientific.net/kem.495.75.

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Electronic nose is a device that attempts to mimic the living being smell system for detection of particular gases or volatile compounds. This paper reports the development of an optical electronic nose using Fe (III) based metalloporphyrins Langmuir-Blodgett thin films as sensing elements for discriminating four volatiles, 2-propanol, acetone, cyclohexane and ethanol. A multilayer feed forward neural network was developed to classify the input vectors from these two sensors. After the network being trained 100 times and introduced to blind samples, it was found that there are three fault decision for propanol, two for acetone, five for cyclohexane and one four ethanol, during 50 times being recognized to the samples.
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Narendranath, S., Netra S. Pillai, Srikar P. Tadepalli, Menelaos Sarantos, K. Vadodariya, A. Sarwade, Radhakrishna V e A. Tyagi. "Sodium Distribution on the Moon". Astrophysical Journal Letters 937, n. 2 (26 settembre 2022): L23. http://dx.doi.org/10.3847/2041-8213/ac905a.

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Abstract The Moon is significantly depleted in volatile elements when compared to Earth, an observation that has resulted in various formation scenarios leading to the loss of volatiles. Sodium is a moderately volatile element that is a lithophile, which can be utilized as a tracer of the volatile history in planetary bodies. It is also well observed in the exosphere of several bodies in our solar system and exoplanetary systems. But lunar surface sodium abundances have so far been measured only in samples brought back to Earth. We report on results from the first effort to provide a global-scale measurement of sodium on the lunar surface using X-ray fluorescent spectra from Chandrayaan-2. A global average of 1.33 ± 0.03 wt% derived here is higher than previously known. Trends in the sodium abundance indicate a long-lived adsorbate component that could explain the higher abundances reported here, which would act as a reservoir that sustains the lunar sodium exosphere.
20

Sawoszczuk, Tomasz, Justyna Syguła-Cholewińska e Julio M. del Hoyo-Meléndez. "The detection of active moulds on historical silk by the means of the headspace–solid phase micro-extraction–gas chromatography–mass spectrometry method". Textile Research Journal 88, n. 9 (17 febbraio 2017): 1013–25. http://dx.doi.org/10.1177/0040517517693984.

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The goal of this work was to analyze the profile of microbial volatile organic compounds (MVOCs) emitted by moulds growing on silk samples in search of particular volatiles mentioned in the literature as indicators of active mould growth. The selected moulds were inoculated on three types of media: (1) samples of pure silk placed on microbial media, (2) samples of historical silk placed on microbial media, and (3) agar containing amino acids that are elements of the structure of fibroin. All samples were prepared inside vials (closed system). In the first and second cases the media did not contain any sources of organic carbon, nitrogen, or sulfur—the silk was the only nutrient for the moulds. A fourth type of sample was historical silk prepared in a Petri dish without a microbial medium and inoculated with a fibroinolytically active mould (open system). The MVOCs emitted by moulds were sampled with the headspace–solid phase micro-extraction method. Volatiles extracted on Divinylbenzene/Carboxen/Polydimethylsiloxane (DVB/CAR/PDMS) fibers were analyzed in a gas chromatography–mass spectrometry system. Qualitative and quantitative analyses of chromatograms were carried out in search of indicators of metabolic activity. The results showed that there are three groups of volatiles that can be used for the detection of active forms of moulds on silk. Thus, this can be a valuable tool for the fast detection of mould activity on historical silk objects. To the best of our knowledge, this is the first work to measure MVOCs emitted by moulds growing on silk.
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Fenske, Myles P., Kristen D. Hewett Hazelton, Andrew K. Hempton, Jae Sung Shim, Breanne M. Yamamoto, Jeffrey A. Riffell e Takato Imaizumi. "Circadian clock gene LATE ELONGATED HYPOCOTYL directly regulates the timing of floral scent emission in Petunia". Proceedings of the National Academy of Sciences 112, n. 31 (29 giugno 2015): 9775–80. http://dx.doi.org/10.1073/pnas.1422875112.

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Flowers present a complex display of signals to attract pollinators, including the emission of floral volatiles. Volatile emission is highly regulated, and many species restrict emissions to specific times of the day. This rhythmic emission of scent is regulated by the circadian clock; however, the mechanisms have remained unknown. In Petunia hybrida, volatile emissions are dominated by products of the floral volatile benzenoid/phenylpropanoid (FVBP) metabolic pathway. Here we demonstrate that the circadian clock gene P. hybrida LATE ELONGATED HYPOCOTYL (LHY; PhLHY) regulates the daily expression patterns of the FVBP pathway genes and floral volatile production. PhLHY expression peaks in the morning, antiphasic to the expression of P. hybrida GIGANTEA (PhGI), the master scent regulator ODORANT1 (ODO1), and many other evening-expressed FVBP genes. Overexpression phenotypes of PhLHY in Arabidopsis caused an arrhythmic clock phenotype, which resembles those of LHY overexpressors. In Petunia, constitutive expression of PhLHY depressed the expression levels of PhGI, ODO1, evening-expressed FVBP pathway genes, and FVBP emission in flowers. Additionally, in the Petunia lines in which PhLHY expression was reduced, the timing of peak expression of PhGI, ODO1, and the FVBP pathway genes advanced to the morning. Moreover, PhLHY protein binds to cis-regulatory elements called evening elements that exist in promoters of ODO1 and other FVBP genes. Thus, our results imply that PhLHY directly sets the timing of floral volatile emission by restricting the expression of ODO1 and other FVBP genes to the evening in Petunia.
22

González Hernández, Jonay I., Garik Israelian, Nuno C. Santos, Sergio Sousa, Elisa Delgado-Mena, Vasco Neves e Stéphane Udry. "Volatiles and refratories in solar analogs: No terrestial planet connection". Proceedings of the International Astronomical Union 6, S276 (ottobre 2010): 422–23. http://dx.doi.org/10.1017/s174392131102062x.

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AbstractWe have analysed very high-quality HARPS and UVES spectra of 95 solar analogs, 24 hosting planets and 71 without detected planets, to search for any possible signature of terrestial planets in the chemical abundances of volatile and refractory elements with respect to the solar abundances.We demonstrate that stars with and without planets in this sample show similar mean abundance ratios, in particular, a sub-sample of 14 planet-host and 14 “single” solar analogs in the metallicity range 0.14 < [Fe/H] < 0.36. In addition, two of the planetary systems in this sub-sample, containing each of them a super-Earth-like planet with masses in the range ~ 7-11 Earth masses, have different volatile-to-refratory abundance ratios to what would be expected from the presence of a terrestial planets.Finally, we check that after removing the Galactic chemical evolution effects any possible difference in mean abundances, with respect to solar values, of refratory and volatile elements practically dissappears.
23

Wojnowski, Wojciech, Mariusz Marć, Kaja Kalinowska, Paulina Kosmela e Bożena Zabiegała. "Emission Profiles of Volatiles during 3D Printing with ABS, ASA, Nylon, and PETG Polymer Filaments". Molecules 27, n. 12 (14 giugno 2022): 3814. http://dx.doi.org/10.3390/molecules27123814.

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In this short communication we characterize the emission of volatile organic compounds (VOCs) from fused filament fabrication (FFF) 3D printing using four polymer materials, namely polyethylene terephthalate glycol-modified (PETG), acrylonitrile styrene acrylate (ASA), Nylon, and acrylonitrile butadiene styrene (ABS). Detailed emission profiles are obtained during thermal degradation of the polymers as a function of temperature and also in real-time during 3D printing. Direct quantitative measurement was performed using proton transfer reaction time-of-flight mass spectrometry (PTR-ToF-MS). Qualitative determination of the volatiles emitted from the printed elements at various temperatures was accomplished using gas chromatography-mass spectrometry (GC-MS). The emission rates of VOCs differ significantly between the different polymer filaments, with the emission from Nylon and PETG more than an order of magnitude lower than that of ABS.
24

Martins, Rayssa, Sven Kuthning, Barry J. Coles, Katharina Kreissig e Mark Rehkämper. "Nucleosynthetic isotope anomalies of zinc in meteorites constrain the origin of Earth’s volatiles". Science 379, n. 6630 (27 gennaio 2023): 369–72. http://dx.doi.org/10.1126/science.abn1021.

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Material inherited from different nucleosynthesis sources imparts distinct isotopic signatures to meteorites and terrestrial planets. These nucleosynthetic isotope anomalies have been used to constrain the origins of material that formed Earth. However, anomalies have only been identified for elements with high condensation temperatures, leaving the origin of Earth’s volatile elements unconstrained. We determined the isotope composition of the moderately volatile element zinc in 18 bulk meteorites and identified nucleosynthetic zinc isotope anomalies. Using a mass-balance model, we find that carbonaceous bodies, which likely formed beyond the orbit of Jupiter, delivered about half of Earth’s zinc inventory. Combined with previous constraints obtained from studies of other elements, these results indicate that ~10% of Earth’s mass was provided by carbonaceous material.
25

Rankin, A. H., M. F. Miller e J. S. Carter. "The release of trace elements and volatiles from crinoidal limestone during thermal decrepitation". Mineralogical Magazine 51, n. 362 (ottobre 1987): 517–25. http://dx.doi.org/10.1180/minmag.1987.051.362.06.

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AbstractA suite of coarsely crystalline samples of crinoidal limestone adjacent to a PbS-CaF2-CaCO3 vein in the North Pennine orefield (Greenhow Rake) was analysed by three independent methods [Inductively Coupled Plasma emission spectroscopy (ICP), Mass Spectrometry (MS) and Gas Chromatography (GC)], in order to determine the nature and origin of trace elements and volatiles released on heating and thermal decrepitation, to establish whether fluid inclusions from the host limestone differed in composition from those within the vein, and to assess the value of the results obtained for mineral exploration. The ICP method gave reproducible results for Ca, Na and K, and significant values for Pb and Zn. Na and K correlate with H2O levels determined by MS/volumetric analysis, suggesting their coexistence within fluid inclusions. No such correlation was found for Pb and Zn, suggesting that these elements were derived by volatilisation, perhaps from traces of galena and sphalerite. Methane showed no correlation with H2O and a source other than aqueous fluid inclusions is thought probable for this volatile.The vein calcite showed much lower K/Na fluid ratios (0.05 cf 0.1–0.2), than the limestones. The limestone-hosted fluids occur predominantly in crinoid ossicles and are believed to represent early pre-mineralisation fluids, unrelated to those associated with veining. Combined ICP and MS techniques may be of value in investigating samples where fluid inclusions are too small for microthermometric and optical analysis.
26

Wang, Ming-Sheng, e Michael E. Lipschutz. "Thermal Metamorphism of Primitive Meteorites—XII. The Enstatite Chondrites Revisited". Environmental Chemistry 2, n. 3 (2005): 215. http://dx.doi.org/10.1071/en04075.

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Environmental Context.The first Solar System material condensed 4.567 billion years ago, rapidly forming planetesimals—solid bodies that might combine to form planets (accretion) or survive as asteroidal meteorites. Earth’s main accretion ended within the next 30 million years, but subsequent high temperatures essentially erased evidence of this history. However, heating in these early episodes produced effects uniquely recorded by 14 volatile trace elements. The volatile element composition of chondritic meteorites, whose parent material formed closest to Earth, may thus provide important information about early planetesimal evolution. Abstract.We report data for 14 trace and ultratrace elements—Au, Co, Sb, Ga, Rb, Ag, Cs, Te, Zn, Cd, Bi, Tl, In (ordered by increasing putative nebular volatility)—in 13 enstatite (E) chondrites recovered from Antarctica and two E inclusions in the Kaidun polymict breccia that fell in 1980. These data, determined by radiochemical neutron activation analysis (RNAA), essentially double the amount of information known for E chondrites, whose parent materials formed closest to the Sun in the chondrite-forming nebular region. We discuss here the data for all 29 samples studied. The meteoritic suite studied here includes both representatives of previously rare types—like high-iron EH3 and EH5 individuals—but also unique individuals and previously unknown low-iron, EL3, chondrites. Prior hypothetical assertions by others are corrected by the new data. Volatile element contents of EL3 and EH3 chondrites are variable, but comparable, like those of type 3 ordinary chondrites (i.e. H3, L3, and LL3). Volatile element contents of EH4 chondrites are at least as high as those of the E3 types, in contrast to the lower contents of H4, L4, and LL4 types. Compositionally, E3,4 chondrites reflect only nebular condensation and/or accretion processes. Volatiles in E5 and E6 chondrites—whether of EH, EL or unique ones—are depleted relative to cosmic (i.e. CI1) or E3,4 chondrite abundances. The evidence indicates that E5,6 chondrites compositionally reflect vaporization and loss of volatiles during open-system, thermal metamorphism of their parent(s); this may have been the terrestrial environment during Earth’s formation from early planetesimals. Compositional differences between Antarctic E5,6 chondrites and contemporary falls probably do not reflect weathering during the long residence of these chondrites in Antarctica. They might reflect differences in the starting compositions and/or metamorphic conditions in the parent(s).
27

Levashova, Ekaterina V., Sergey G. Skublov, Dmitry A. Zamyatin, Qiuli Li, Dmitry S. Levashov e Xianhua Li. "Tetrad Effect of Rare Earth Element Fractionation in Zircon from the Pegmatite of the Adui Massif, Middle Urals". Geosciences 14, n. 1 (23 dicembre 2023): 7. http://dx.doi.org/10.3390/geosciences14010007.

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The zircon from the pegmatite of the Adui granitic massif displays the unique the rare earth element (REE) distribution spectrum with the tetrad effect in REE fractionation. The tetrad effect often occurs in granitoid rocks, but it is rarely encountered in minerals, e.g., zircon. Fluid saturated with volatiles, water and trace elements is a factor responsible for the tetrad effect in the zircon. The detailed isotopic-geochemical study of the zircon has revealed several zones differing in internal structure (in the back-scattered electron (BSE) image), composition and REE distribution. The zones indicate changes in the crystallization environment provoked by the evolution of the pegmatite-forming melt. They occur as the gradually growing changes in composition from the unaltered zones that are light-colored in BSE to the altered zones that are dark-colored in BSE. The unaltered zones are consistent in composition and geochemical features with magmatic zircons. The high content of trace (U, Th, REE) and volatile elements (F, Cl) in water suggests its crystallization from the fluid-saturated magmatic melt. The altered zircon zones occur as recrystallized zones with high content of non-formula elements (Y, Ca, Sr, Nb, P), a non-differentiated REE distribution spectrum and an absent Ce anomaly. These features are consistent with those of hydrothermal-metasomatic zircon.
28

Ali, Muhammad Yasir, Tayyaba Naseem, Jarmo K. Holopainen, Tongxian Liu, Jinping Zhang e Feng Zhang. "Tritrophic Interactions among Arthropod Natural Enemies, Herbivores and Plants Considering Volatile Blends at Different Scale Levels". Cells 12, n. 2 (7 gennaio 2023): 251. http://dx.doi.org/10.3390/cells12020251.

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Herbivore-induced plant volatiles (HIPVs) are released by plants upon damaged or disturbance by phytophagous insects. Plants emit HIPV signals not merely in reaction to tissue damage, but also in response to herbivore salivary secretions, oviposition, and excrement. Although certain volatile chemicals are retained in plant tissues and released rapidly upon damaged, others are synthesized de novo in response to herbivore feeding and emitted not only from damaged tissue but also from nearby by undamaged leaves. HIPVs can be used by predators and parasitoids to locate herbivores at different spatial scales. The HIPV-emitting spatial pattern is dynamic and heterogeneous in nature and influenced by the concentration, chemical makeup, breakdown of the emitted mixes and environmental elements (e.g., turbulence, wind and vegetation) which affect the foraging of biocontrol agents. In addition, sensory capability to detect volatiles and the physical ability to move towards the source were also different between natural enemy individuals. The impacts of HIPVs on arthropod natural enemies have been partially studied at spatial scales, that is why the functions of HIPVs is still subject under much debate. In this review, we summarized the current knowledge and loopholes regarding the role of HIPVs in tritrophic interactions at multiple scale levels. Therefore, we contend that closing these loopholes will make it much easier to use HIPVs for sustainable pest management in agriculture.
29

Sossi, Paolo A., Frédéric Moynier e Kirsten van Zuilen. "Volatile loss following cooling and accretion of the Moon revealed by chromium isotopes". Proceedings of the National Academy of Sciences 115, n. 43 (8 ottobre 2018): 10920–25. http://dx.doi.org/10.1073/pnas.1809060115.

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Terrestrial and lunar rocks share chemical and isotopic similarities in refractory elements, suggestive of a common precursor. By contrast, the marked depletion of volatile elements in lunar rocks together with their enrichment in heavy isotopes compared with Earth’s mantle suggests that the Moon underwent evaporative loss of volatiles. However, whether equilibrium prevailed during evaporation and, if so, at what conditions (temperature, pressure, and oxygen fugacity) remain unconstrained. Chromium may shed light on this question, as it has several thermodynamically stable, oxidized gas species that can distinguish between kinetic and equilibrium regimes. Here, we present high-precision Cr isotope measurements in terrestrial and lunar rocks that reveal an enrichment in the lighter isotopes of Cr in the Moon compared with Earth’s mantle by 100 ± 40 ppm per atomic mass unit. This observation is consistent with Cr partitioning into an oxygen-rich vapor phase in equilibrium with the proto-Moon, thereby stabilizing the CrO2 species that is isotopically heavy compared with CrO in a lunar melt. Temperatures of 1,600–1,800 K and oxygen fugacities near the fayalite–magnetite–quartz buffer are required to explain the elemental and isotopic difference of Cr between Earth’s mantle and the Moon. These temperatures are far lower than modeled in the aftermath of a giant impact, implying that volatile loss did not occur contemporaneously with impact but following cooling and accretion of the Moon.
30

Dippong, Thomas, Oana Cadar, Melinda Haydee Kovacs, Monica Dan e Lacrimioara Senila. "Chemical Analysis of Various Tea Samples Concerning Volatile Compounds, Fatty Acids, Minerals and Assessment of Their Thermal Behavior". Foods 12, n. 16 (15 agosto 2023): 3063. http://dx.doi.org/10.3390/foods12163063.

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Tea is the most consumed drink worldwide due to its pleasant taste and various beneficial effects on human health. This paper assesses the physicochemical analysis of different varieties of tea (leaves, flowers, and instant) after prior drying and fine grinding. The thermal decomposition behavior of the tea components shows that the tea has three stages of decomposition, depending on temperature. The first stage was attributed to the volatilization of water, while the second stage involved the degradation of volatiles, polyphenols, and fatty acids. The degradation of cellulose, hemicellulose, and lignin content occurs at the highest temperature of 400 °C in the third stage. A total of 66 volatile compounds, divided into eight classes, were identified in the tea samples. The volatile compounds were classified into nine odor classes: floral, fruity, green, sweet, chemical, woody, citrus, roasted, and alcohol. In all flower and leaf tea samples, monounsaturated (MUFAs), polyunsaturated (PUFAs), and saturated fatty acids (SFAs) were identified. A high content of omega-6 was quantified in acacia, Saint John’s Wort, rose, and yarrow, while omega-3 was found in mint, Saint John’s Wort, green, blueberry, and lavender samples. The flower and leaf tea samples studied could be a good dietary source of polyphenolic compounds, essential elements. In instant tea samples, a low quantity of polyphenols and major elements were identified. The physicochemical analysis demonstrated that both flower and leaf teas have high-quality properties when compared to instant tea.
31

Simons, Kyla, Jacqueline Dixon, Jean-Guy Schilling, Richard Kingsley e Robert Poreda. "Volatiles in basaltic glasses from the Easter-Salas y Gomez Seamount Chain and Easter Microplate: Implications for geochemical cycling of volatile elements". Geochemistry, Geophysics, Geosystems 3, n. 7 (luglio 2002): 1–29. http://dx.doi.org/10.1029/2001gc000173.

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32

Yang, Jing, Yaochen Li, Yuxin He, Hongying He, Xiaoqi Chen, Tingfu Liu e Biao Zhu. "Wild vs. Cultivated Zingiber striolatum Diels: Nutritional and Biological Activity Differences". Plants 12, n. 11 (31 maggio 2023): 2180. http://dx.doi.org/10.3390/plants12112180.

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Compositional, functional, and nutritional properties are important for the use-value assessments of wild and cultivated edible plants. The aim of this study was to compare the nutritional composition, bioactive compounds, volatile compounds, and potential biological activities of cultivated and wild Zingiber striolatum. Various substances, such as soluble sugars, mineral elements, vitamins, total phenolics, total flavonoids, and volatiles, were measured and analyzed using UV spectrophotometry, ICP-OES, HPLC, and GC-MS methods. The antioxidant capacity of a methanol extract of Z. striolatum, as well as the hypoglycemic abilities of its ethanol and water extracts, were tested. The results showed that the contents of soluble sugar, soluble protein, and total saponin in the cultivated samples were higher, while the wild samples contained higher amounts of K, Na, Se, vitamin C, and total amino acids. The cultivated Z. striolatum also showed a higher antioxidant potential, while the wild Z. striolatum exhibited a better hypoglycemic activity. Thirty-three volatile compounds were identified using GC-MS in two plants, with esters and hydrocarbons being the main volatile compounds. This study demonstrated that both cultivated and wild Z. striolatum have a good nutritional value and biological activity, and can be used as a source of nutritional supplementation or even in medication.
33

Vogt, David S., Susanne Schröder, Lutz Richter, Michael Deiml, Peter Weßels, Jörg Neumann e Heinz-Wilhelm Hübers. "VOILA on the LUVMI-X Rover: Laser-Induced Breakdown Spectroscopy for the Detection of Volatiles at the Lunar South Pole". Sensors 22, n. 23 (6 dicembre 2022): 9518. http://dx.doi.org/10.3390/s22239518.

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The project Lunar Volatiles Mobile Instrumentation—Extended (LUVMI-X) developed an initial system design as well as payload and mobility breadboards for a small, lightweight rover dedicated for in situ exploration of the lunar south pole. One of the proposed payloads is the Volatiles Identification by Laser Analysis instrument (VOILA), which uses laser-induced breakdown spectroscopy (LIBS) to analyze the elemental composition of the lunar surface with an emphasis on sampling regolith and the detection of hydrogen for the inference of the presence of water. It is designed to analyze targets in front of the rover at variable focus between 300 mm and 500 mm. The spectrometer covers the wavelength range from 350 nm to 790 nm, which includes the hydrogen line at 656.3 nm as well as spectral lines of most major rock-forming elements. We report here the scientific input that fed into the concept and design of the VOILA instrument configuration for the LUVMI-X rover. Moreover, we present the measurements performed with the breadboard laboratory setup for VOILA at DLR Berlin that focused on verifying the performance of the designed LIBS instrument in particular for the detection and quantification of hydrogen and other major rock forming elements in the context of in situ lunar surface analysis.
34

Treiman, A. H., J. W. Boyce, J. Gross, Y. Guan, J. M. Eiler e E. M. Stolper. "Phosphate-halogen metasomatism of lunar granulite 79215: Impact-induced fractionation of volatiles and incompatible elements". American Mineralogist 99, n. 10 (1 ottobre 2014): 1860–70. http://dx.doi.org/10.2138/am-2014-4822.

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Galimov, E. M. "Features of the geochemistry of the Moon and the Earth, determined by the mechanism of formation of the Earth – Moon system (report at the 81st international meteorite conference, Moscow, july 2018)". Геохимия 64, n. 8 (3 settembre 2019): 762–76. http://dx.doi.org/10.31857/s0016-7525648762-776.

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This article discusses some features of geochemistry of the Earth and the Moon, which manifests the specificity of the mechanism of their formation by fragmentation of protoplanetary gas-dust condensation (Galimov & Krivtsov, 2012). The principal difference between this model and other hypotheses of the Earth-Moon system formation, including the megaimpact hypothesis, is that it assumes the existence of a long stage of the dispersed state of matter, starting with the formation of protoplanetary gas-dust condensation, its compression and fragmentation and ending with the final accretion to the formed high-temperature embryos of the Earth and the Moon. The presence of the dispersed state allows a certain way to interpret the observed properties of the Earth-Moon system. Partial evaporation of solid particles due to adiabatic heating of the compressing condensation leads to the loss of volatiles including FeO. Computer simulations show that the final accretion is mainly performed on a larger fragment (the Earth’s embryo) and only slightly increases the mass of the smaller fragment (the Moon embryo).This explains the relative depletion of the Moon in iron and volatile and the increased concentration of refractory components compared to the Earth. The reversible nature of evaporation into the dispersed space, in contrast to the kinetic regime, and the removal of volatiles in the hydrodynamic flow beyond the gas-dust condensation determines the loss of volatiles without the effect of isotopes fractionation. The reversible nature of volatile evaporation also provides, in contrast to the kinetic regime, the preservation of part of the high-volatile components, such as water, in the planetary body, including the Moon. It follows from the essence of the model that at least a significant part of the Earth’s core is formed not by segregation of iron in the silicate-metal melt, but by evaporation and reduction of FeO in a dispersed medium, followed by deposition of clusters of elemental iron to the center of mass. This mechanism of formation of the core explains the observed excess of siderophilic elements in the Earth’s mantle. It also provides a plausible explanation for the observed character of iron isotopes fractionation (in terms of δ57Fe‰) on Earth and on the Moon. It solves the problem of the formation of iron core from initially oxide (FeO) form. The dispersed state of the substance during the period of accretion suggests that the loss of volatiles occurred during the time of accretion. Using the fact that isotopic systems: U–Pb, Rb–Sr, 129J–129Xe, 244Pu–136Xe, contain volatile components, it is possible to estimate the chronology of events in the evolution of the protoplanetary state. As a result, agreed estimates of the time of fragmentation of the primary protoplanetary condensation and formation of the embryos of the Earth and the Moon are obtained: from 10 to 40 million years, and the time of completion of the earth’s accretion and its birth as a planetary body: 110 – 130 million years after the emergence of the solar system. The presented interpretation is consistent with the fact that solid minerals on the Moon have already appeared at least 60 million years after the birth of the solar system (Barboni et al., 2017), and the metal core in the Earth and in the Moon could not have formed before 50 million years from the start of the solar system, as follows from the analysis of the Hf-W system (Kleine et al., 2009). It is shown that the hypothesis of megaimpact does not satisfy many constraints and does not create a basis for the explanation of the geochemistry of the Earth and the Moon.
36

Losekamm, Martin J., Janos Biswas, Thibaud Chupin, Michael Deiml, Matthieu Deremetz, Anthony M. Evagora, Guillaume Fau et al. "Assessing the Distribution of Water Ice and Other Volatiles at the Lunar South Pole with LUVMI-X: A Mission Concept". Planetary Science Journal 3, n. 10 (1 ottobre 2022): 229. http://dx.doi.org/10.3847/psj/ac8cfd.

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Abstract The search for exploitable deposits of water and other volatiles at the Moon’s poles has intensified considerably in recent years, due to the renewed strong interest in lunar exploration. With the return of humans to the lunar surface on the horizon, the use of locally available resources to support long-term and sustainable exploration programs, encompassing both robotic and crewed elements, has moved into focus of public and private actors alike. Our current knowledge about the distribution and concentration of water and other volatiles in the lunar rocks and regolith is, however, too limited to assess the feasibility and economic viability of resource-extraction efforts. On a more fundamental level, we currently lack sufficiently detailed data to fully understand the origins of lunar water and its migration to the polar regions. In this paper, we present LUVMI-X, a mission concept intended to address the shortage of in situ data on volatiles on the Moon that results from a recently concluded design study. Its central element is a compact rover equipped with complementary instrumentation capable of investigating both the surface and shallow subsurface of illuminated and shadowed areas at the lunar south pole. We describe the rover and instrument design, the mission’s operational concept, and a preliminary landing-site analysis. We also discuss how LUVMI-X fits into the diverse landscape of lunar missions under development.
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Iwanek (nee Wilczkowska), Ewa M., Urszula Nietrzeba, Marta Pietras, Aleksandra Marciniak, Gustaw Głuski, Jakub Hupka, Miłosz Szymajda et al. "Possible Options for Utilization of EU Biomass Waste: Pyrolysis Char, Calorific Value and Ash Content". Materials 17, n. 1 (31 dicembre 2023): 226. http://dx.doi.org/10.3390/ma17010226.

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The application of biomass as a co-feed in coal power plants and in standalone biomass power plants, as well as in char production for soil remediation, is a currently important issue. This paper reports on the investigation of biochar formation from agricultural waste crops that are used for soil upgrading, but which do not meet the standards of EU crops, as well as largescale food processing waste. These were compared to test results from basket willow, which is commonly used for energy generation. Food industry waste is often produced in cities on a large scale and is generally easier to process due to lack of other stream components. The key parameters, namely, the content of volatiles, energy content of the formed biochar and the composition of the ash, were determined for a number of herbaceous materials locally available in the European Union. All of them can be used as a cheap source of biochar. A novel procedure of capturing volatiles and hence minimizing the PAH content in the biochar, as well as enabling the recovery of energy from the volatiles is presented. Knowledge of the composition and form of elements in ash is very important for designing ash management systems if co-combustion is implemented. The aim of this study was to determine if the types of biomass are better suited for biochar production or energy generation.
38

Matthews, Jennifer L., Maiken Ueland, Natasha Bartels, Caitlin A. Lawson, Thomas E. Lockwood, Yida Wu e Emma F. Camp. "Multi-Chemical Omics Analysis of the Symbiodiniaceae Durusdinium trenchii under Heat Stress". Microorganisms 12, n. 2 (2 febbraio 2024): 317. http://dx.doi.org/10.3390/microorganisms12020317.

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The urgency of responding to climate change for corals necessitates the exploration of innovative methods to swiftly enhance our understanding of crucial processes. In this study, we employ an integrated chemical omics approach, combining elementomics, metabolomics, and volatilomics methodologies to unravel the biochemical pathways associated with the thermal response of the coral symbiont, Symbiodiniaceae Durusdinium trenchii. We outline the complimentary sampling approaches and discuss the standardised data corrections used to allow data integration and comparability. Our findings highlight the efficacy of individual methods in discerning differences in the biochemical response of D. trenchii under both control and stress-inducing temperatures. However, a deeper insight emerges when these methods are integrated, offering a more comprehensive understanding, particularly regarding oxidative stress pathways. Employing correlation network analysis enhanced the interpretation of volatile data, shedding light on the potential metabolic origins of volatiles with undescribed functions and presenting promising candidates for further exploration. Elementomics proves to be less straightforward to integrate, likely due to no net change in elements but rather elements being repurposed across compounds. The independent and integrated data from this study informs future omic profiling studies and recommends candidates for targeted research beyond Symbiodiniaceae biology. This study highlights the pivotal role of omic integration in advancing our knowledge, addressing critical gaps, and guiding future research directions in the context of climate change and coral reef preservation.
39

Zedler, Marie, Sze Wai Tse, Antonio Ruiz-Gonzalez e Jim Haseloff. "Paper-Based Multiplex Sensors for the Optical Detection of Plant Stress". Micromachines 14, n. 2 (26 gennaio 2023): 314. http://dx.doi.org/10.3390/mi14020314.

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The rising population and the ongoing climate crisis call for improved means to monitor and optimise agriculture. A promising approach to tackle current challenges in food production is the early diagnosis of plant diseases through non-invasive methods, such as the detection of volatiles. However, current devices for detection of multiple volatiles are based on electronic noses, which are expensive, require complex circuit assembly, may involve metal oxides with heating elements, and cannot easily be adapted for some applications that require miniaturisation or limit front-end use of electronic components. To address these challenges, a low-cost optoelectronic nose using chemo-responsive colorimetric dyes drop-casted onto filter paper has been developed in the current work. The final sensors could be used for the quantitative detection of up to six plant volatiles through changes in colour intensities with a sub-ppm level limit of detection, one of the lowest limits of detection reported so far using colorimetric gas sensors. Sensor colouration could be analysed using a low-cost spectrometer and the results could be processed using a microcontroller. The measured volatiles could be used for the early detection of plant abiotic stress as early as two days after exposure to two different stresses: high salinity and starvation. This approach allowed a lowering of costs to GBP 1 per diagnostic sensing paper. Furthermore, the small size of the paper sensors allows for their use in confined settings, such as Petri dishes. This detection of abiotic stress could be easily achieved by exposing the devices to living plants for 1 h. This technology has the potential to be used for monitoring of plant development in field applications, early recognition of stress, implementation of preventative measures, and mitigation of harvest losses.
40

Wu, Li, Zhuang, Querol, Moreno, Li, Ge et al. "Mineralogical and Environmental Geochemistry of Coal Combustion Products from Shenhuo and Yihua Power Plants in Xinjiang Autonomous Region, Northwest China". Minerals 9, n. 8 (19 agosto 2019): 496. http://dx.doi.org/10.3390/min9080496.

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The mineralogical and geochemical characteristics of feed coals and coal combustion products (CCPs) from the Shenhuo and Yihua Power Plants in Xinjiang Autonomous Region, were studied by means of proximate analysis, Power X-ray diffraction (XRD), scanning electron microscopy with Energy Dispersive X-ray analyzer (SEM-EDX), inductively coupled plasma atomic emission spectrometry (ICP-MS) and inductively coupled plasma mass spectrometry (ICP-AES). The environmental geochemistry of CCPs was evaluated by Al-normalized enrichment factor as well as European Standard EN-12457 leaching test. Two feed coals have the characteristics of low sulfur content, medium to high volatiles matter yields, medium moisture content, super low to medium ash yield, medium to high calorific value and low mineral content. The main crystalline facies in fly ash and slag are quartz and mullite, with a small amount of calcite, and some unburned carbon. Hematite, SrSO4 and barite also can be observed in fly ashes by SEM. Typical plerophere occurs in fine fly ash rather than the coarse fly ash. The concentration of most trace elements in CCPs falls within the lower concentration range of European fly ashes. With respect to the partitioning behavior of trace elements during coal combustion, S is highly volatile, and Mg, Na, Zn, B, Co, As, Nb, Zr, Cu and K also show certain volatility, which may to some extent emit to the atmosphere. Furthermore, leaching experiments show that leachable concentrations of most of the potentially toxic elements in CCPs are low, and the CCPs fall in the range between inert and nonhazardous landfill material regulated by the 2003/33/EC Decision.
41

Bussweiler. "Polymineralic Inclusions in Megacrysts as Proxies for Kimberlite Melt Evolution—A Review". Minerals 9, n. 9 (30 agosto 2019): 530. http://dx.doi.org/10.3390/min9090530.

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Polymineralic inclusions in megacrysts have been reported to occur in kimberlites worldwide. The inclusions are likely the products of early kimberlite melt(s) which invaded the pre‐existing megacryst minerals at mantle depths (i.e., at pressures ranging from 4 to 6 GPa) and crystallized or quenched upon emplacement of the host kimberlite. The abundance of carbonate minerals (e.g., calcite, dolomite) and hydrous silicate minerals (e.g., phlogopite, serpentine, chlorite) within polymineralic inclusions suggests that the trapped melt was more volatile‐rich than the host kimberlite now emplaced in the crust. However, the exact composition of this presumed early kimberlite melt, including the inventory of trace elements and volatiles, remains to be more narrowly constrained. For instance, one major question concerns the role of accessory alkali‐halogen‐phases in polymineralic inclusions, i.e., whether such phases constitute a common primary feature of kimberlite melt(s), or whether they become enriched in late‐stage differentiation processes. Recent studies have shown that polymineralic inclusions react with their host minerals during ascent of the kimberlite, while being largely shielded from processes that affect the host kimberlite, e.g., the assimilation of xenoliths (mantle and crustal), degassing of volatiles, and secondary alteration. Importantly, some polymineralic inclusions within different megacryst minerals were shown to preserve fresh glass. A major conclusion of this review is that the abundance and mineralogy of polymineralic inclusions are directly influenced by the physical and chemical properties of their host minerals. When taking the different interactions with their host minerals into account, polymineralic inclusions in megacrysts can serve as useful proxies for the multi‐stage origin and evolution of kimberlite melt/magma, because they can (i) reveal information about primary characteristics of the kimberlite melt, and (ii) trace the evolution of kimberlite magma on its way from the upper mantle to the crust.
42

Righter, Kevin. "Modeling siderophile elements during core formation and accretion, and the role of the deep mantle and volatiles". American Mineralogist 100, n. 5-6 (maggio 2015): 1098–109. http://dx.doi.org/10.2138/am-2015-5052.

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Sadofsky, Seth J., Maxim Portnyagin, Kaj Hoernle e Paul van den Bogaard. "Subduction cycling of volatiles and trace elements through the Central American volcanic arc: evidence from melt inclusions". Contributions to Mineralogy and Petrology 155, n. 4 (2 ottobre 2007): 433–56. http://dx.doi.org/10.1007/s00410-007-0251-3.

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44

Aikawa, Yuri, e Kenji Furuya. "Gas-dust chemistry of volatiles in the star and planetary system formation". Proceedings of the International Astronomical Union 15, S350 (aprile 2019): 161–68. http://dx.doi.org/10.1017/s1743921319008263.

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AbstractThe focus of this work is on two topics: (i) formation of complex organic molecules (COMs) and (ii) isotope fractionation. Various COMs, which are C, H-containing molecules consisting of 6 atoms and more, have been detected in the central warm region of protostellar cores. Most of this review is about gas-grain chemical models, which have been constructed to evaluate the mechanisms and efficiency of the COM formation. The relevant physical and chemical processes are investigated in laboratory experiments, as reported in other articles in this volume.The isotope fractionation of volatile elements is observed in both the interstellar medium (ISM) and Solar system material. While exothermic exchange reactions enrich molecules with heavier isotopes such as Deuterium, the isotope selective photodissociation can be coupled with ice formation to enrich the ice mantle with rare isotopes. The efficiency of this fractionation depends on the photodesorption yields, which has been studied in laboratory experiments.
45

Kröncke, Nina, Sandra Grebenteuch, Claudia Keil, Sebastian Demtröder, Lothar Kroh, Andreas Thünemann, Rainer Benning e Hajo Haase. "Effect of Different Drying Methods on Nutrient Quality of the Yellow Mealworm (Tenebrio molitor L.)". Insects 10, n. 4 (27 marzo 2019): 84. http://dx.doi.org/10.3390/insects10040084.

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Yellow mealworm (Tenebrio molitor L.) represents a sustainable source of proteins and fatty acids for feed and food. Industrial production of mealworms necessitates optimized processing techniques, where drying as the first postharvest procedure is of utmost importance for the quality of the final product. This study examines the nutritional quality of mealworm larvae processed by rack oven drying, vacuum drying or freeze drying, respectively. Proximate composition and fatty acid profile were comparable between the dried larvae. In contrast, larvae color impressions and volatile compound profiles were very much dependent on processing procedure. High-temperature rack oven drying caused pronounced darkening with rather low content of volatiles, pointing toward the progress of Maillard reaction. On the other hand, vacuum drying or freeze drying led to enrichment of volatile Maillard reaction and lipid oxidation intermediates, whose actual sensory relevance needs to be clarified in the future. Beyond sensory and visual importance drying intermediates have to be considered with regard to their metal ion chelating ability; in particular for essential trace elements such as Zn2+. This study found comparable total zinc contents for the differently dried mealworm samples. However, dried larvae, in particular after rack oven drying, had only low zinc accessibility, which was between 20% and 40%. Therefore, bioaccessibility rather than total zinc has to be considered when their contribution to meeting the nutritional requirements for zinc in humans and animals is evaluated.
46

Kendrick, Mark A., e Jaime D. Barnes. "Sediments, Serpentinites, and Subduction: Halogen Recycling from the Surface to the Deep Earth". Elements 18, n. 1 (1 febbraio 2022): 21–26. http://dx.doi.org/10.2138/gselements.18.1.21.

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Halogens are important elements that participate in a variety of biogeo-chemical processes and influence the solubility of metals in subduction-zone fluids. Halogens are powerful tracers of subducted volatiles in the Earth’s mantle because they have high abundances in seawater, sediments, and altered oceanic lithosphere but low concentrations in the mantle. Additionally, Br/Cl and I/Cl ratios, as well as Cl-isotope ratios, have characteristic ranges in different surface reservoirs that are not easily fractionated in the mantle. Current data suggest that subduction of serpentinised lithosphere is a major source of halogens in the Earth’s mantle.
47

Zhou, Jiehao, Hui Zhang, Yong Tang, Zhenghang Lv e Shenjin Guan. "Characteristics and Geological Significance of CO2-Rich Fluid Inclusions in Dakalasu No. 1 Pegmatite Dyke, Altay". Minerals 13, n. 3 (6 marzo 2023): 365. http://dx.doi.org/10.3390/min13030365.

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The fluids in of pegmatite rare metal deposits are generally rich in rare metal elements and volatiles (B, P, F, H2O, CO2, etc.), and they have a high capacity for dissolving and migrating rare metals. The Dakalasu No. 1 rare metal pegmatite vein is located in northwest China’s Altay orogenic belt. Previous studies have indicated that it is a small- to medium-sized beryllium-niobium-tantalum deposit. It showed significant mineral assemblage zonations from the rim to the core, and the mineralizing fluids define a volatile-rich NaCl-H2O-CO2 ± CH4 system. In this contribution, beryl and quartz, which are widely developed in each mineral association and textural zone, were selected for fluid inclusion research through detailed petrographic investigation, microthermometry, and LA-ICP-MS analysis. Petrographic results show that at least three types of fluid inclusions are developed in each mineral textural zone. They are CO2-rich inclusions (type I), gas-liquid two-phase inclusions (type II), and daughter mineral-bearing inclusions (type III), respectively. Additionally, minor melt inclusions (type IV) are visible in the beryl from the rim zone. Microthermometric measurements showed that the homogenization temperature of fluid inclusions in the rim zone was concentrated between 242 °C and 293 °C, with an average of 267 °C, and the salinity was between 7.2–10.3 wt% NaCleqv, with an average of 8.6 wt% NaCleqv. In comparison, the temperature of the core zone was in the range of 225–278 °C, with an average of 246 °C, and the salinity focused between 6.0–7.7 wt% NaCleqv, with an average of 7.1 wt% NaCleqv. The quantitative analysis of individual inclusions by LA-ICP-MS revealed that Li, B, K, Zn, Rb, Sb, Cs, and As were relatively enriched in the rim zone. In contrast, the core zone showed a decreasing trend in trace elements such as Li, B, K, Rb, and Cs. The CO2 content in the fluid exhibited the same decreasing trend from the rim to the core zone, indicating that volatile components such as CO2 played an essential role in the migration and enrichment of rare metal elements. The melt-fluid immiscibility is likely to be a necessary mechanism for significantly enriching rare metals in the Dakalasu No. 1 pegmatite dyke.
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Kaneoka, Ichiro. "Kimberlites vs. ocean-island basalts: Comparison as an indicator for volatiles and some other elements in deep mantle". Geochimica et Cosmochimica Acta 70, n. 18 (agosto 2006): A305. http://dx.doi.org/10.1016/j.gca.2006.06.618.

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Giuliani, Andrea, e D. Graham Pearson. "Kimberlites: From Deep Earth to Diamond Mines". Elements 15, n. 6 (1 dicembre 2019): 377–80. http://dx.doi.org/10.2138/gselements.15.6.377.

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Kimberlites are rare, enigmatic, low-volume igneous rocks. They are highly enriched in magnesium, volatiles (CO2 and H2O) and incompatible trace elements and are thought to be the most deeply derived (&gt;150 km) magmatic rocks on Earth. Kimberlites occur in ancient and thick continental lithosphere, forming intrusive sheets and composite pipes, commonly in clusters. Despite their rarity, kimberlites have attracted considerable attention because they entrain not only abundant mantle fragments but also diamonds, which can provide a uniquely rich picture of the deep Earth. This issue summarises current thinking on kimberlite petrology, geochemistry, and volcanology and outlines the outstanding questions on the genesis of kimberlites and associated diamond mines.
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Radulović, Niko, e Polina Blagojević. "Volatile Profiles of Artemisia alba from Contrasting Serpentine and Calcareous Habitats". Natural Product Communications 5, n. 7 (luglio 2010): 1934578X1000500. http://dx.doi.org/10.1177/1934578x1000500729.

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GC and GC-MS analyses of the essential oils of two populations of Artemisia alba Turra, wild-growing on calcareous and serpentine substrates, enabled the identification of 227 different components. Volatile profiles of the two samples differed significantly and only 48 components were in common to both oils. Major constituents of the oils were as follows: germacrene D (38.3%) in the serpentinophyte A. alba (sometimes regarded as A. alba ssp. saxatilis or A. saxatilis) oil and spathulenol (11.8%), artemisia ketone (10.1%), camphor (7.5%) and 1,8-cineole (7.4%) in A. alba (from calcareous habitat) oil. The noted differences were observable on the class level as well: with 73% the sesquiterpenoids (48.2% hydrocarbons, 24.5% oxygen or sulfur containing) were the most abundant compound class in A. saxatilis oil, while the other oil was dominated by monoterpenoids, comprising ca. 60% of the oil (2.1% hydrocarbons and 54.7% oxygenated). Additionally, the serpentinophyte yielded ca. four times less essential oil. These results pointed out to the fact that the type of substrate (soil) could have an important influence on the biosynthesis of A. alba volatiles (genetically predetermined or environmental), especially in the case of populations grown on serpentine rock, characterized by a deficiency of water and indispensable mineral elements.

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