Artykuły w czasopismach: „Al-Cu-Hf-Zr”

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Inoue, Akihisa, Bao Long Shen i Akira Takeuchi. "Syntheses and Applications of Fe-, Co-, Ni- and Cu-Based Bulk Glassy Alloys". Materials Science Forum 539-543 (marzec 2007): 92–99. http://dx.doi.org/10.4028/www.scientific.net/msf.539-543.92.

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This paper reviews our recent results of the formation, fundamental properties, workability and applications of late transition metal (LTM) base bulk glassy alloys (BGAs) developed since 1995. The BGAs were obtained in Fe-(Al,Ga)-(P,C,B,Si), Fe-(Cr,Mo)-(C,B), Fe-(Zr,Hf,Nb,Ta)-B, Fe-Ln-B(Ln=lanthanide metal), Fe-B-Si-Nb and Fe-Nd-Al for Fe-based alloys, Co-(Ta,Mo)-B and Co-B-Si-Nb for Co-based alloys, Ni-Nb-(Ti,Zr)-(Co,Ni) for Ni-based alloys, and Cu-Ti-(Zr,Hf), Cu-Al-(Zr,Hf), Cu-Ti-(Zr,Hf)-(Ni,Co) and Cu-Al-(Zr,Hf)-(Ag,Pd) for Cu-based alloys. These BGAs exhibit useful properties of high mechanical strength, large elastic elongation and high corrosion resistance. In addition, Fe- and Co-based glassy alloys have good soft magnetic properties which cannot be obtained for amorphous and crystalline type magnetic alloys. The Feand Ni-based BGAs have already been used in some application fields. These LTM base BGAs are promising as new metallic engineering materials.

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Tomolya, Kinga, Márton Benke, Dóra Janovszky i Árpád Kovács. "Hf Particles Reinforced Cu-Zr-Al Amorphous Powder Produced by Milling". Materials Science Forum 752 (marzec 2013): 30–36. http://dx.doi.org/10.4028/www.scientific.net/msf.752.30.

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This research work dealt with production of amorphous powder with nominal composition of (Cu55Zr45Al10)97Hf3 (at%). Combining the mechanical milling and alloying, powder of crystalline Cu-Zr-Al alloy mixed with Hf elemental powder were milled in order to produce a homogenous and amorphous alloy powder The master alloy and the powders milled for different time were analyzed by X-Ray Analysis (XRD) and Scanning Electron Microscopy (SEM). Particle size distribution and hardness were controlled during milling and at the end of procedure. The milling caused dissolving of the hafnium. The 25 h milling time was the optimal to obtain the Hf containing powder with amorphous structure. However, elemental Hf traces with size below 3 µm were still observed in the powder. After 50 h of milling, such impurity elements as iron, nickel, chromium originating from milling tools (vial, balls) were detected.

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Saida, Junji, Chunfei Li, Mitsuhide Matsushita i Akihisa Inoue. "Investigation of the stability of glassy state in the Zr- and Hf-based glassy alloys correlated with their transformation behavior". Journal of Materials Research 16, nr 12 (grudzień 2001): 3389–401. http://dx.doi.org/10.1557/jmr.2001.0467.

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The transformation behavior from glassy state was investigated in Zr- and Hf-based glassy alloys. The primary phases are metastable face-centered-cubic (fcc) Zr2Ni and fcc Hf2Ni phases in the Zr65Al7.5Ni10Cu17.5 and Hf65Al7.5Ni10Cu17.5 glassy alloys, respectively. By substitution of 5 at.% Pd for Cu, the primary phase changes to an icosahedral quasicrystalline phase in both alloys. It is found that the addition of elements, which have a positive or weak chemical affinity with one of the constitutional elements in the Zr–Al–Ni–Cu and Hf–Al–Ni–Cu glassy alloys, is effective for the precipitation of the icosahedral phase. It is suggested that Pd plays a dominant role in an increase in the number of nucleation sites. Since an icosahedron is contained as a structure unit in the icosahedral, fcc Zr2Ni and fcc Hf2Ni phases, it is implied that these phases are correlated with the local icosahedral order. The high-resolution transmission electron microscopy images of the as-spun Zr65Al7.5Ni10Cu7.5Pd10 and Hf65Al7.5Ni10Cu12.5Pd5 alloys reveal a possibility of the existence of the icosahedral ordered regions. It is therefore, concluded that the icosahedral short- or medium-range order exists and it stabilizes the glassy state in the Zr- and Hf-based multicomponent alloys.

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Nokhrin, Aleksey, Iana Shadrina, Vladimir Chuvil’deev, Vladimir Kopylov, Nikolay Berendeev, Artem Murashov, Aleksandr Bobrov, Nataliya Tabachkova, Elena Smirnova i Mikhail Faddeev. "Investigation of Thermal Stability of Microstructure and Mechanical Properties of Bimetallic Fine-Grained Wires from Al–0.25%Zr–(Sc,Hf) Alloys". Materials 15, nr 1 (27.12.2021): 185. http://dx.doi.org/10.3390/ma15010185.

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Thermal stability of composite bimetallic wires from five novel microalloyed aluminum alloys with different contents of alloying elements (Zr, Sc, and Hf) is investigated. The alloy workpieces were obtained by induction-casting in a vacuum, preliminary severe plastic deformation, and annealing providing the formation of a uniform microstructure and the nucleation of stabilizing intermetallide Al3(Zr,Sc,Hf) nanoparticles. The wires of 0.26 mm in diameter were obtained by simultaneous deformation of the Al alloy with Cu shell. The bimetallic wires demonstrated high strength and improved thermal stability. After annealing at 450–500 °C, a uniform fine-grained microstructure formed in the wire (the mean grain sizes in the annealed Al wires are 3–5 μm). An increased hardness and strength due to nucleation of the Al3(Sc,Hf) particles was observed. A diffusion of Cu from the shell into the surface layers of the Al wire was observed when heating up to 400–450 °C. The Cu diffusion depth into the annealed Al wire surfaces reached 30–40 μm. The maximum elongation to failure of the wires (20–30%) was achieved after annealing at 350 °C. The maximum values of microhardness (Hv = 500–520 MPa) and of ultimate strength (σb = 195–235 MPa) after annealing at 500 °C were observed for the wires made from the Al alloys alloyed with 0.05–0.1% Sc.

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Popova, Elvira, Pavel Kotenkov, Ivan Gilev, Stepan Pryanichnikov i Alexey Shubin. "Effect of Copper on the Formation of L12 Intermetallic Phases in Al–Cu–X (X = Ti, Zr, Hf) Alloys". Metals 12, nr 12 (30.11.2022): 2067. http://dx.doi.org/10.3390/met12122067.

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Transition metal trialuminides of the Al3X type of groups 4 and 5 of the periodic system have reduced density, high melting points, and corrosion resistance. Aluminides with a cubic lattice of the Al3Sc type can be used as a nucleating phase for aluminum alloys. However, low plasticity and a tetragonal lattice limit their application. In this work, we stabilized the metastable cubic lattice of Al3X-type aluminides by replacing aluminum with copper. The conditions for the formation of L12 metastable aluminides in the Al‒Cu‒TM (TM: Ti, Zr, Hf) alloys were studied using a wide range of copper concentrations. A high concentration of copper (hypereutectic alloys) is the one of the necessary conditions for the formation of (Al1−хCuх)3Ti, (Al1−хCuх)3Zr, (Al1−хCuх)3Hf aluminides. With an increase in the copper concentration, the number of metastable aluminides sharply increased. The process of their formation strongly depended on the sequence of dissolution of the corresponding components in the melts. The low volume fraction of precipitated titanium aluminides was the result of insufficient supersaturation of α-Al with titanium (at the peritectic temperature) compared to that for alloys with zirconium and hafnium. Under identical synthesis conditions in the crystal lattice of metastable aluminides formed in experimental Al–Cu–Ti, Al–Cu–Zr, Al–Cu–Hf alloys, copper was found to substitute up to 8, 10, and 13 at.% of aluminum, respectively. The crystallographic and dimensional similarities of the lattices in metastable transition metal aluminides and in α-Al suggest their usefulness as modifying additions in aluminum-based alloys.

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Gao, Q., H. Zhang, R. Yang, Z. Fan, Y. Liu, J. Wang, X. Geng i in. "Effect of alloying elements on the stacking fault energies of dilute al-based alloys". Journal of Mining and Metallurgy, Section B: Metallurgy 54, nr 2 (2018): 185–96. http://dx.doi.org/10.2298/jmmb180107007g.

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A systematic study of the stacking fault energy (?SF) for the dilute Al-based alloys (Al23X, Al47X and Al71X, where X = Al, Ag, Be, Ca, Cd, Co, Cu, Cr, Fe, Ga, Ge, Hf, In, K, La, Li, Mn, Mg, Ni, Na, Pb, Sc, Sn, Sr, Si, Ti, V, Zn, and Zr) has been performed by means of first-principles calculations. Alias shear deformation is adopted in the present investigations. The presently calculated ?SF for Al is in favorable accordance with experimental and other theoretical data. For the targeted elements, the calculations indicate that Na, Si, K, Ca, Sc, Ga, Ge, Sr, Zr, In, Sn, La, Hf, and Pb, in any concentration we considered, decrease the ?SF of Al, while Ag, Be, Cd, Co, Cu, Cr, Fe, Li, Mn, Mg, Ni, Ti, V, and Zn increase the ?SF of Al, when the concentration of alloying elements is 1.39 at. % in the system. With increasing concentration of alloying elements, Li, Mg, V, Ti, and Cd change from increasing the ?SF of Al to decreasing it, based on present investigations. Among the alloying elements, which decrease the ?SF of Al, La decreases the ?SF most significantly. It is also found that the ?SF of Al-X generally decreases with the increase of equilibrium volume. The results obtained in the present work provide an insight into the design of Al based alloys.

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Gu, X., T. Jiao, L. J. Kecskes, R. H. Woodman, C. Fan, K. T. Ramesh i T. C. Hufnagel. "Crystallization and mechanical behavior of (Hf, Zr)–Ti–Cu–Ni–Al metallic glasses". Journal of Non-Crystalline Solids 317, nr 1-2 (marzec 2003): 112–17. http://dx.doi.org/10.1016/s0022-3093(02)01990-7.

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Gao, Bo, Yiwei Zhao, Xiaoye Du, Yaqi Chen, Boyuan Guan, Yan Li, Yanhuai Li i in. "Facile phase transition engineering of MoS2 for electrochemical hydrogen evolution". Journal of Materials Chemistry A 9, nr 13 (2021): 8394–400. http://dx.doi.org/10.1039/d0ta12076f.

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Magnetron sputtering and DFT calculations revealed that the single-doped Cu-MoS₂, Au-MoS₂, Ag-MoS₂, and Al-MoS₂ exhibited distinct phase transitions compared to Cr-MoS₂, Hf-MoS₂, Ta-MoS₂, and Zr-MoS₂, due to the introduction of additional charge.

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Breiter, Karel, Axel Müller, Robin Shail i Beth Simons. "Composition of zircons from the Cornubian Batholith of SW England and comparison with zircons from other European Variscan rare-metal granites". Mineralogical Magazine 80, nr 7 (grudzień 2016): 1273–89. http://dx.doi.org/10.1180/minmag.2016.080.071.

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AbstractZircon from 14 representative granite samples of the late-Variscan Cornubian Batholith in SW England was analysed for W, P, As, Nb, Ta, Si, Ti, Zr, Hf, Th, U, Y, La, Ce, Pr, Nd, Sm, Gd, Dy, Er, Yb, Al, Sc, Bi, Mn, Fe, Ca, Pb, Cu, S and F using electron probe microanalyses. Zircons from the biotite and tourmaline granites are poor in minor and trace elements, usually containing 1.0–1.5 wt.% HfO2, <0.5 wt.% UO2 and P2O5, <0.25 wt.% Y2O3, <0.2 wt.% Sc2O3 and Bi2O3 and <0.1 wt.% ThO2. Zircon from topaz granites from the St. Austell Pluton, Meldon Aplite and Megiliggar Rocks are slightly enriched in Hf (up to 4 wt.% HfO2), U (1– 3.5 wt.% UO2) and Sc (0.5–1 wt.% Sc2O3). Scarce metamictized zircon grains are somewhat enriched in Al, Ca, Fe and Mn. The decrease of the zircon Zr/Hf ratio, a reliable magma fractionation index, from 110–60 in the biotite granites to 30–10 in the most evolved topaz granites (Meldon Aplite and Megiliggar Rocks), supports a comagmatic origin of the biotite and topaz granites via long-lasting fractionation of common peraluminous crustal magma. In comparison with other European rare-metal provinces, the overall contents of trace elements in Cornubian zircons are low and the Zr/Hf and U/Th ratios show lower degrees of fractionation of the parental melt.

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Kim, K. B., P. J. Warren i B. Cantor. "Metallic glass formation in multicomponent (Ti, Zr, Hf, Nb)–(Ni, Cu, Ag)–Al alloys". Journal of Non-Crystalline Solids 317, nr 1-2 (marzec 2003): 17–22. http://dx.doi.org/10.1016/s0022-3093(02)02002-1.

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Qin, Chun Ling, Zhi Feng Wang, Hui Liu, Li Liu, Hao Wang, Jian Ding i Wei Min Zhao. "Monolithic Nanoporous Copper with Novel Electrochemical Properties Fabricated by Dealloying Cu-Zr(-Al) Metallic Glasses". Materials Science Forum 783-786 (maj 2014): 1925–30. http://dx.doi.org/10.4028/www.scientific.net/msf.783-786.1925.

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Monolithic uniform nanoporous Cu (NPC) ribbons with a ligament/pore size of 10-25 nm are successfully synthesized by chemical dealloying the Cu50Zr50 and Cu50Zr45Al5 metallic glasses in 0.5 M HF for 7 min. It is found that the length scale of ligaments/channels can be tuned by simply alloying 5 at.% Al to the Cu-Zr binary glassy alloys. The current signal of the NPC-supported MnO2 composite electrode is remarkably enhanced as compared to that of pure MnO2 powders. These new findings greatly raise the hope for possible applications of NPC as a new type of electrode substrates or an advanced sensor in green and new energy technology.

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Uher, Pavel, Stanislava Milovská, Rastislav Milovský, Peter Koděra, Peter Bačík i Vladimír Bilohuščin. "Kerimasite, {Ca3}[Zr2](SiFe3+2)O12 garnet from the Vysoká-Zlatno skarn, Štiavnica stratovolcano, Slovakia". Mineralogical Magazine 79, nr 3 (czerwiec 2015): 715–33. http://dx.doi.org/10.1180/minmag.2015.079.3.15.

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AbstractKerimasite {Ca3}[Zr2](SiFe23+)O12, a rare member of the garnet supergroup, has been identified in association with andradite–grossular and their hydrated analogues, monticellite, perovskite, clintonite, anhydrite, hydroxylellestadite–fluorellestadite, spinel, magnetite, brucite, valeriite and other minerals from a Ca-Mg skarn in the exocontact of a granodiorite porphyry intrusion in Vysoká-Zlatno Cu-Au skarn-porphyry deposit, the Štiavnica stratovolcano, Central Slovakia. Kerimasite forms euhedral-to-anhedral crystals, 2 to 100 μm across with 0.73–1.62 atoms per formula unit (a.p.f.u.) Zr (16.2–33.6 wt.% ZrO2), 0.34–0.66 a.p.f.u. Ti (4.6–9.3 wt.% TiO2), 0.01 to 0.05 a.p.f.u. Hf (0.4–1.7 wt.% HfO2: the largest Hf content reported in kerimasite), and small amounts of Sn, Sc and Nb (≤0.02 a.p.f.u.). Tetrahedral Si (0.99–1.67 a.p.f.u.; 9.8–18.1 wt.% SiO2) is balanced by 0.85–1.26 a.p.f.u. Fe3+ and by 0.46–0.76 a.p.f.u. Al. The crystals commonly show regular, oscillatory concentric zoning or irregular patchy internal textures due to Zr, Ti, Fe, Al and Si variations during growth or partial alteration and dissolution-reprecipitation. The main substitutions in kerimasite are Y(Fe,Sc)3+ + ZSi4+ = Y(Zr,Ti,Hf,Sn)4+ + Z(Fe,Al)3+ and Ti4+ = Zr4+. Associated andradite locally contains irregular Ti- and Zr-rich zones with ≤11 wt.% TiO2 and ≤4.4 wt.% ZrO2. In comparison with common Ca-rich garnets, the micro-Raman spectrum of kerimasite shows that many bands shift towards much lower wavenumbers, either due to Fe3+ substitution on the Z site or to the strong influence of neighbouring octahedrally-coordinated Zr4+ on internal vibrations of tetrahedra that share oxygens. The formation of kerimasite, monticellite, perovskite and other phases indicate a relatively Ca-rich and Si, Al-poor environment, analogous to other known occurrences of Ca-Zr garnets (Ca-rich skarns and xenoliths, carbonatites). Kerimasite and associated skarn minerals originated during contact-thermal metamorphism of Upper Triassic marl slates with limestone, dolomite, anhydrite and gypsum by Miocene granodiorite porphyry at T ≈ 700°C and P ≈ 50–70 MPa.

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Kumagai, Tomohisa, Shotaro Hara, Satoshi Izumi i Shinsuke Sakai. "Development of a Method for Making Interatomic Potential: An Application to Metallic Systems". Materials Science Forum 539-543 (marzec 2007): 2123–28. http://dx.doi.org/10.4028/www.scientific.net/msf.539-543.2123.

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A method for making interatomic potentials is proposed and is applied to Cu-Zr-Hf-Ni- Al bulk-metallic-glass systems. The method consists of three steps. Firstly, potential function form is determined so that bonding nature can be described. Secondly, materials properties used for fitting are selected so that the potential has enough robustness. Here, it is noted that materials properties must be added in accordance with the purpose of the study. Finally, potential parameters have been optimized using global-search procedure. Developed potential well reproduces material properties of them.

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Matijošius, Tadas, Giedrius Stalnionis, Gedvidas Bikulčius, Sigitas Jankauskas, Laurynas Staišiūnas i Svajus Joseph Asadauskas. "Antifrictional Effects of Group IVB Elements Deposited as Nanolayers on Anodic Coatings". Coatings 13, nr 1 (10.01.2023): 132. http://dx.doi.org/10.3390/coatings13010132.

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The utilization of anodized aluminum (Al) components would contribute greatly to combat against dry friction if good tribological properties could be attained. Despite its hardness, the wear rate of anodic coatings presents a major problem in many applications, including automotive, aerospace and high-tech industries. Recently, nanolayers of Ti demonstrated high tribological effectiveness and unusually low dry friction on anodic coatings. However, few researchers focus on the tribological characterization of nanolayers of other elements. In this study, nanolayers of Ti, Zr, Hf, Cu, Cr, Nb and Sn were deposited on anodized 1050 and 6082 alloys by magnetron sputtering and Atomic Layer Deposition. Major attention was devoted to surface roughness and hardness measurements, because of their importance for static friction. The results showed that structural, chemical and other intrinsic properties of nanolayers of Group IVB elements in many cases led to significant friction reduction, when compared to those of Cu, Cr and Hf. Nanolayers of 15 nm to 75 nm thicknesses appeared most effective tribologically, while 180 nm or thicker layers progressively lost their ability to sustain low dynamic friction. Deposition of nanoscale structures could provide advantages for the anodized Al industry in protection against incidental friction and wear.

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Park, E. S., J. S. Kyeong i D. H. Kim. "Phase separation and improved plasticity by modulated heterogeneity in Cu–(Zr,Hf)–(Gd,Y)–Al metallic glasses". Scripta Materialia 57, nr 1 (lipiec 2007): 49–52. http://dx.doi.org/10.1016/j.scriptamat.2007.03.008.

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Bozzolo, Guillermo, Ronald D. Noebe i Hugo O. Mosca. "Site preference of ternary alloying additions to NiTi: Fe, Pt, Pd, Au, Al, Cu, Zr and Hf". Journal of Alloys and Compounds 389, nr 1-2 (marzec 2005): 80–94. http://dx.doi.org/10.1016/j.jallcom.2004.07.051.

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Zítek, M., P. Zeman, M. Kotrlová i R. Čerstvý. "Impact of Al or Si addition on properties and oxidation resistance of magnetron sputtered Zr–Hf–Al/Si–Cu metallic glasses". Journal of Alloys and Compounds 772 (styczeń 2019): 409–17. http://dx.doi.org/10.1016/j.jallcom.2018.09.069.

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Ajtic, Jelena, Darko Sarvan, Branislava Mitrovic, Ana Cuculovic, Rodoljub Cuculovic i Marina Frontasyeva. "Elemental composition of moss and lichen species in eastern Serbia". Nuclear Technology and Radiation Protection 33, nr 3 (2018): 275–85. http://dx.doi.org/10.2298/ntrp1803275a.

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Instrumental neutron activation analysis is used to determine a content of 47 elements (Na, Mg, Al, Cl, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Ni, Co, Cu, Zn, As, Se, Br, Rb, Sr, Zr, Mo, Ag, Cd, Sb, I, Ba, Cs, La, Ce, Nd, Sm, Eu, Gd, Tb, Dy, Tm, Yb, Lu, Hf, Ta, W, Au, Hg, Th, and U) in mosses (Homolothecium sp., Hypnum cupressiforme Hedw., and Brachythecium mildeanum (Schimp.) Schimp.) and lichen (Cladonia fimbriata (L.) Fr.) collected in three locations in Eastern Serbia over years 2006-2010. Concentrations of six elements (Zr, Nd, Gd, Tm, Yb, and Lu) in mosses in Serbia are measured for the first time. For other elements, the obtained concentrations fall within the ranges reported for mosses and lichens in Europe, but no declining trend in concentrations of V, Cd, Cr, Zn, Ni, Fe, and Cu, that has been described in the literature, can be inferred from our results. Factor analysis shows that terrigenous and industrial components are the highest contributing factors to the elemental composition and that the most polluted measurement site is in the vicinity of a copper mining and smelting complex.

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Zhang, L. C., Z. Q. Shen i J. Xu. "Glass formation in a (Ti, Zr, Hf)–(Cu, Ni, Ag)–Al high-order alloy system by mechanical alloying". Journal of Materials Research 18, nr 9 (wrzesień 2003): 2141–49. http://dx.doi.org/10.1557/jmr.2003.0300.

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In this work, glass formation under high-energy ball milling was investigated for a (Ti0.33Zr0.33Hf0.33)50(Ni0.33Cu0.33Ag0.33)40Al10 high-order alloy system with equiatomic substitution for early and late transition-metal contents. For comparison, an amorphous alloy ribbon with the same composition was prepared using the melt-spinning method as well. Structural features of the samples were characterized using x-ray diffraction, transmission electron microscopy, and differential scanning calorimetry. Mechanical alloying resulted in a glassy alloy similar to that obtained by melt spinning. However, the glass formation was incomplete, and a small amount of unreacted crystallites smaller than 30 nm in size still remained in the final ball-milled product. Like the melt-spun glass, the ball-milled glassy alloy also exhibited a distinct glass transition and a wide supercooled liquid region of about 80 K. Crystallization of this high-order glassy alloy proceeded through two main stages. After the primary nanocrystallization was completed, the remaining amorphous phase also behaved as a glass, showing a detectable glass transition and a large supercooled liquid region of about 100 K.

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Zhang, L. C., i J. Xu. "Glass-forming ability of melt-spun multicomponent (Ti, Zr, Hf)–(Cu, Ni, Co)–Al alloys with equiatomic substitution". Journal of Non-Crystalline Solids 347, nr 1-3 (listopad 2004): 166–72. http://dx.doi.org/10.1016/j.jnoncrysol.2004.09.007.

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Феоктистов, Владимир Михайлович, i Павел Владимирович Медведев. "МИКРОЭЛЕМЕНТНЫЙ СОСТАВ ВОДНЫХ ЭКСТРАКТОВ НЕКОТОРЫХ ОБРАЗЦОВ ДИАТОМИТОВ И ЛИДИТОВ КАРЕЛИИ". Izvestiya Tomskogo Politekhnicheskogo Universiteta Inziniring Georesursov 331, nr 2 (18.02.2020): 199–205. http://dx.doi.org/10.18799/24131830/2020/2/2506.

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Актуальность исследования обусловлена необходимостью получения достоверной информации об элементном составе водных экстрактов диатомитов и лидитов. В настоящее время диатомиты используются в различных отраслях промышленности, в том числе медицинской и фармацевтической. Однако детального изучения состава их водных экстрактов практически не проводилось. Цель: изучить микроэлементный состав водных экстрактов нескольких образцов диатомитов и лидитов. Объекты: три образца диатомитов и два образца лидитов территории Республики Карелия. Методика: лабораторный эксперимент, водная экстракция, масс-спектрометрия с индуктивно-связанной плазмой (ICP MS). Результаты. Изучен элементный состав водных экстрактов нескольких образцов диатомитов и лидитов территории Республики Карелия методом ICP MS. Во всех исследованных экстрактах образцов диатомитов и лидитов преобладающими элементами являются Mg, Na, Ca, K и Al (до нескольких тысяч мкг/л). Экстракты образцов диатомитов имеют однородный состав. Максимальные содержания в них других, наиболее значимых, элементов составляли: P – до 650, Fe – до 1700 (образец № 1) и Mn – до 3300 (образец № 3) мкг/л. Концентрации в диапазоне от 10 до 100 мкг/л характерны для ряда элементов (Li, B, Ti, Cr, Co, Ni, Cu, Zn, Sr, Y, Zr и Ba) в экстрактах всех образцов диатомитов. Экстракты образцов диатомитов № 1 и 2 имели максимальные концентрации легких редкоземельных элементов (РЗЭ): Nd (до 247), Ce (до 230), La (до 156 мкг/л). Химический состав экстрактов образцов лидитов заметно отличался, как между собой, так и от экстрактов диатомитов. Кислая среда (рН 4,5–4,6) экстракта образца № 4 способствовала накоплению ряда элементов: Ni, Sr, Be, Mn, U, Tl, и особенно V, Co, Cu, Zn, Y, Ba. В то же время в экстракте образца № 5 в слабощелочных условиях (рН 7,4–7,5) наблюдались максимальные концентрации Mo, W, Zr, Hf. В исследованных экстрактах образцах диатомитов и лидита № 4 концентрации Al, Mn, Fe, Co, Ni, Cu, Zn превышали значения предельно допустимых концентраций (ПДК) рыбохозяйственных водоемов. Водные экстракты образцов диатомитов показали значительное содержание элементов, которые могут оказать влияние на формирование состава маломинерализованных карельских вод. При этом содержание ряда полезных для развития растений микроэлементов (Ca, Mg, К, Р, Cu, Zn, V, Mn, Sr, Y, Zr) предполагает возможность их использования как «мягких» удобрений (или добавок к минеральным удобрениям).

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Stepanova, V. A., i N. P. Mironycheva-Tokareva. "Lateral and radial geochemical structure of bog catena soils (on the example of middle-taiga bog system of Western Siberia)". IOP Conference Series: Earth and Environmental Science 928, nr 1 (1.12.2021): 012012. http://dx.doi.org/10.1088/1755-1315/928/1/012012.

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Abstract Lateral and radial geochemical structure of bog catena soils of Western Siberia middle-taiga subzone has been investigated on the base of B, Na, Mg, Al, P, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, As, Rb, Sr, Y, Zr, Mo, Cd, Sb, Cs, Ba, Hf, W, Pb, Th, U and lanthanoides content. Bog catena is characterized with high contrast of radial distribution of most studied elements. Lateral differentiation is significantly lower than radial one and is monotonous for most elements. In bog catena soils of Western Siberia middle-taiga subzone there are investigated correlations between elements content and soils characteristics that are mainly determined by specific peculiarities of ecosystem development.

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Hou, Zhiguan, Qingjie Gong, Ningqiang Liu, Biao Jiang, Jie Li, Yuan Wu, Jiaxin Huang i Weixuan Gu. "Elemental Abundances of Moon Samples Based on Statistical Distributions of Analytical Data". Applied Sciences 13, nr 1 (27.12.2022): 360. http://dx.doi.org/10.3390/app13010360.

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The successful return of Chang’E-5 (CE5) samples urges the hot topic of the study of the Moon in geochemistry. The elemental data of the analyzed moon samples reported in the literature were collected to determine the elemental abundances in moon samples. Based on 2365 analytical records of moon samples from ten missions of Apollo, Luna, and CE5, elemental abundances of 11 major oxides including Cr2O3, 50 trace elements including Ti, P, Mn, Cr, and 15 rare earth elements (REEs) including Y are derived based on statistical distributions of normal, log-normal, and additive log-ratio transformation, respectively. According to the value of 13.5% CaO content, moon samples are classified into two types, as low-Ca and high-Ca samples, whose elemental abundances are also calculated respectively based on the methods used in the total moon samples. With respect to the mid-ocean ridge basalt (MORB) of the Earth, moon samples (including the Moon, low-Ca, and high-Ca samples) are rich in Cr, REEs, Th, U, Pb, Zr, Hf, Cs, Ba, W, and Be and poor in Na, V, Cu, and Zn in terms of their concentrations, and are enriched in Cr and depleted in Na, K, Rb, P, V, Cu, Zn in spider diagrams. The CE5 sample is a low-Ca type of moon sample and is clearly rich in Ti, Fe, Mn, P, Sc, REEs, Th, U, Nb, Ta, Zr, Hf, Sr, Ba, W, and Be and poor in Mg, Al, Cr, and Ni in terms of their concentrations relative to the moon or the low-Ca samples. If compared with the moon sample, the CE5 sample is also clearly rich in K, REE, and P.

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Shulyak, Alexandra T., Evgeniy O. Bortnikov, Nikita A. Selivanov, Mikhail S. Grigoriev, Alexey S. Kubasov, Andrey P. Zhdanov, Alexander Y. Bykov, Konstantin Y. Zhizhin i Nikolai T. Kuznetsov. "Nucleophilic Substitution Reactions in the [B3H8]− Anion in the Presence of Lewis Acids". Molecules 27, nr 3 (24.01.2022): 746. http://dx.doi.org/10.3390/molecules27030746.

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As a result of our study on the interaction between the octahydrotriborate anion with nucleophiles (Nu = THF, Ph3P, Ph2P-(CH2)2-PPh2 (dppe), Ph3As, Et3N, PhNH2, C5H5N, CH3CN, Ph2CHCN)) in the presence of a wide range of Lewis acids (Ti(IV), Hf(IV), Zr(IV), Al, Cu(I), Zn, Mn(II), Co(II) halides and iodine), a number of substituted derivatives of the octahydrotriborate anion [B3H7Nu] are obtained. It is found that the use of TiCl4, AlCl3, ZrCl4, HfCl4, CuCl and iodine leads to the highest product yields. In this case, it is most likely that the reaction proceeds through the formation of an intermediate [B3H7-HMXnx], which was detected by NMR spectroscopy. The structures of [Ph3P·B3H7] and [PhNH2·B3H7] were determined by X-ray diffraction.

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Wada, Takeshi, Jing Jiang, Kunio Yubuta, Hidemi Kato i Akira Takeuchi. "Septenary Zr–Hf–Ti–Al–Co–Ni–Cu high-entropy bulk metallic glasses with centimeter-scale glass-forming ability". Materialia 7 (wrzesień 2019): 100372. http://dx.doi.org/10.1016/j.mtla.2019.100372.

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Žibret, Gorazd. "Elemental Associations in Stream and Alluvial Sediments of the Savinja and Voglajna Rivers (Slovenia, EU) as a Result of Natural Processes and Anthropogenic Activities". Minerals 12, nr 7 (5.07.2022): 861. http://dx.doi.org/10.3390/min12070861.

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Stream and alluvial sediments of the Savinja and Voglajna rivers were sampled, and sediment fractions <0.063 and 0.063–0.125 mm were analyzed on the content of 60 of the main and trace elements. The objective was to determine elemental associations and identify possible sources of these associations. Differences of Al/Ti oxides ratio (9.7–26) can be attributed to the variations in the source rocks, while the K/Al oxides ratio indicates erosional or depositional river regime and variation in source rocks. One anthropogenic and three natural associations of elements were identified. The anthropogenic association (Ag, In, Sb, Cu, As, Zn, Pb, Cd, Bi, Mo and Sn) is linked to historic Zn smelting in the Celje area, and the subsequent erosion of the material from inadequately managed pyrometallurgical waste deposit. The second association (Li, Sc, Al, V, Cs and Ga) is linked to clay minerals, the third one (Mg, Ca and Te) to carbonate rocks, and the fourth one (Hf, Zr) to the heavy mineral fraction.

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Wang, J., Y. Du, S. L. Shang, Z. K. Liu i Y. Li. "Effects of alloying elements on elastic properties of Al by first-principles calculations". Journal of Mining and Metallurgy, Section B: Metallurgy 50, nr 1 (2014): 37–44. http://dx.doi.org/10.2298/jmmb140116002w.

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The effects of alloying elements (Co, Cu, Fe, Ge, Hf, Mg, Mn, Ni, Si, Sr, Ti, V, Y, Zn, and Zr) on elastic properties of Al have been investigated using first-principles calculations within the generalized gradient approximation. A supercell consisting of 31 Al atoms and one solute atom is used. A good agreement is obtained between calculated and available experimental data. Lattice parameters of the studied Al alloys are found to be depended on atomic radii of solute atoms. The elastic properties of polycrystalline aggregates including bulk modulus (B), shear modulus (G), Young?s modulus (E), and the B/G ratio are also determined based on the calculated elastic constants (cij?s). It is found that the bulk modulus of Al alloys decreases with increasing volume due to the addition of alloying elements and the bulk modulus is also related to the total molar volume (Vm) and electron density (nAl31x) with the relationship of nAl31x=1.0594+0.0207?B/Vm. These results are of relevance to tailor the properties of Al alloys.

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Jin, Z. S., Y. J. Yang, Z. P. Zhang, X. Z. Ma, J. W. Lv, F. L. Wang, M. Z. Ma, X. Y. Zhang i R. P. Liu. "Effect of Hf substitution Cu on glass-forming ability, mechanical properties and corrosion resistance of Ni-free Zr–Ti–Cu–Al bulk metallic glasses". Journal of Alloys and Compounds 806 (październik 2019): 668–75. http://dx.doi.org/10.1016/j.jallcom.2019.07.240.

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Zhang, Ying, Chengfu Lyu, Xue Gao, Zhaoqing Dang, Zhaotong Sun, Qianshan Zhou i Guojun Chen. "Geochemical Characteristics and Organic Matter Accumulation of Wufeng-Longmaxi Shales in the Southeast of the Sichuan Basin of South China". Geofluids 2022 (19.12.2022): 1–19. http://dx.doi.org/10.1155/2022/7360065.

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The Upper Ordovician Wufeng Formation and Lower Silurian Longmaxi Formation black shales are the critical targets for shale gas exploration in the Sichuan Basin of South China. The enrichment of organic matter (OM) in shale is the basis for the generation of large-scale shale gas; however, its controlling factors in Wufeng-Longmaxi shales are still under debate, and few studies have focused on the edge of the Sichuan Basin. Based on the mineral composition, total organic carbon (TOC), and systematic inorganic geochemistry analysis of 72 core samples from Wufeng and Longmaxi formations in Well Xike 1, southeastern Sichuan Basin, the sedimentary conditions (palaeoclimate, palaeoredox, and palaeoproductivity) were reconstructed, and the controlling factors of OM enrichment were identified. The mineral compositions are dominated by quartz, clay minerals, calcite, and feldspar, associated with minor dolomite, pyrite, and anhydrite. The TOC contents (0.31%-6.84%, avg. 2.22%) show an upward decreasing trend from the Wufeng Formation to Longmaxi Formation. The chemical index of alteration (CIA) ranges from 65 to 71 (avg. 69), indicating warm and humid climate with moderate weathering. The diagrams of Al2O3-TiO2, TiO2-Zr, Zr/Sc-Th/Sc, La/Th-Hf, and La-Th-Sc jointly indicate the contribution from felsic and intermediate rock weathering. The P/Al, Cu/Al, and Ni/Al ratios suggest that marine paleoproductivity was relatively high in the Wufeng Formation and relatively low to moderate in the Longmaxi Formation. The V/Cr, V/Sc, U/Th, MoEF/UEF, and Corg/P ratios indicate that the bottom water was anoxic during the Wufeng Formation deposition and then fluctuating dysoxic and/or oxic in the overlying Longmaxi Formation. The TOC content was positively correlated with productivity proxies (P/Al, Cu/Al, and Ni/Al) as well as redox proxies (U/Th, V/Cr, MoEF/UEF, and Corg/P), indicating that the OM accumulation in Wufeng-Longmaxi shales is mainly controlled by high productivity and anoxic bottom water conditions.

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Huang, Xiao-Wen, Anne-Aurélie Sappin, Émilie Boutroy, Georges Beaudoin i Sheida Makvandi. "Trace Element Composition of Igneous and Hydrothermal Magnetite from Porphyry Deposits: Relationship to Deposit Subtypes and Magmatic Affinity". Economic Geology 114, nr 5 (1.08.2019): 917–52. http://dx.doi.org/10.5382/econgeo.4648.

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Abstract The trace element composition of igneous and hydrothermal magnetite from 19 well-studied porphyry Cu ± Au ± Mo, Mo, and W-Mo deposits was measured by laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) and then classified by partial least squares-discriminant analysis (PLS-DA) to constrain the factors explaining the relationships between the chemical composition of magnetite and the magmatic affinity and porphyry deposit subtypes. Igneous magnetite can be discriminated by relatively high P, Ti, V, Mn, Zr, Nb, Hf, and Ta contents but low Mg, Si, Co, Ni, Ge, Sb, W, and Pb contents, in contrast to hydrothermal magnetite. Compositional differences between igneous and hydrothermal magnetite are mainly controlled by the temperature, oxygen fugacity, cocrystallized sulfides, and element solubility/mobility that significantly affect the partition coefficients between magnetite and melt/fluids. Binary diagrams based on Ti, V, and Cr contents are not enough to discriminate igneous and hydrothermal magnetite in porphyry deposits. Relatively high Si and Al contents discriminate porphyry W-Mo hydrothermal magnetite, probably reflecting the control by high-Si, highly differentiated, granitic intrusions for this deposit type. Relatively high Mg, Mn, Zr, Nb, Sn, and Hf but low Ti and V contents discriminate porphyry Au-Cu hydrothermal magnetite, most likely resulting from a combination of mafic to intermediate intrusion composition, high chlorine in fluids, relatively high oxygen fugacity, and low-temperature conditions. Igneous or hydrothermal magnetite from Cu-Mo, Cu-Au, and Cu-Mo-Au deposits cannot be discriminated from each other, probably due to similar intermediate to felsic intrusion composition, melt/fluid composition, and conditions such as temperature and oxygen fugacity for the formation of these deposits. The magmatic affinity of porphyritic intrusions exerts some control on the chemical composition of igneous and hydrothermal magnetite in porphyry systems. Igneous and hydrothermal magnetite related to alkaline magma is relatively rich in Mg, Mn, Co, Mo, Sn, and high field strength elements (HFSEs), perhaps due to high concentrations of chlorine and fluorine in magma and exsolved fluids, whereas those related to calc-alkaline magma are relatively rich in Ca but depleted in HFSEs, consistent with the high Ca but low HFSE magma composition. Igneous and hydrothermal magnetite related to high-K calc-alkaline magma is relatively rich in Al, Ti, Sc, and Ta, due to a higher temperature of formation or enrichment of these elements in melt/fluids. Partial least squares-discriminant analysis on hydrothermal magnetite compositions from porphyry Cu, iron oxide copper-gold (IOCG), Kiruna-type iron oxide-apatite (IOA), and skarn deposits around the world identify important discriminant elements for these deposit types. Magnetite from porphyry Cu deposits is characterized by relatively high Ti, V, Zn, and Al contents, whereas that from IOCG deposits can be discriminated from other types of magnetite by its relatively high V, Ni, Ti, and Al contents. IOA magnetite is discriminated by higher V, Ti, and Mg but lower Al contents, whereas skarn magnetite can be separated from magnetite from other deposit types by higher Mn, Mg, Ca, and Zn contents. Decreased Ti and V contents in hydrothermal magnetite from porphyry Cu and IOA, to IOCG, and to skarn deposits may be related to decreasing temperature and increasing oxygen fugacity. The relative depletion of Al in IOA magnetite is due to its low magnetite-silicate melt partition coefficient, immobility of Al in fluids, and earlier, higher-temperature magmatic or magmatic-hydrothermal formation of IOA deposits. The relative enrichment of Ni in IOCG magnetite reflects more mafic magmatic composition and less competition with sulfide, whereas elevated Mn, Mg, Ca, and Zn in skarn magnetite results from enrichment of these elements in fluids via more intensive fluid-carbonate rock interaction.

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Chaligava, Omari, Igor Nikolaev, Khetag Khetagurov, Yulia Lavrinenko, Anvar Bazaev, Marina Frontasyeva, Konstantin Vergel i Dmitry Grozdov. "First Results on Moss Biomonitoring of Trace Elements in the Central Part of Georgia, Caucasus". Atmosphere 12, nr 3 (28.02.2021): 317. http://dx.doi.org/10.3390/atmos12030317.

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The moss biomonitoring technique was used for assessment of air pollution in the central part of Georgia, Caucasus, in the framework of the UNECE ICP Vegetation. A total of 35 major and trace elements were determined by two complementary analytical techniques, epithermal neutron activation analysis (Na, Mg, Al, Cl, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Zn, Se, B, Rb, Sr, Zr, Mo, Sb, I, Cs, Ba, La, Ce, Nd, Sm, Eu, Tb, Yb, Hf, Ta, W, Th, and U) and atomic absorption spectrometry (Cu, Cd, and Pb) in the moss samples collected in 2019. Principal Component Analyses was applied to show the association between the elements in the study area. Four factors were determined, of which two are of geogenic origin (Factor 1 including Na, Al, Sc, Ti, V, Cr, Fe, Co, Ni, Th, and U and Factor 3 with As, Sb, and W), mixed geogenic–anthropogenic (Factor 2 with Cl, K, Zn, Se, Br, I, and Cu) and anthropogenic (Factor 4 comprising Ca, Cd, Pb, and Br). Geographic information system (GIS) technologies were used to construct distributions maps of factor scores over the investigated territory. Comparison of the median values with the analogous data of moss biomonitoring in countries with similar climatic conditions was carried out.

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Xing, Dawei, Jianfei Sun, Jun Shen, Gang Wang i Ming Yan. "The relations between ΔT and the glass forming ability of bulk amorphous Zr–Cu–Ni–Al–Hf–Ti and Zr52.5Cu17.9Ni14.6Al10Ti5 alloys". Journal of Alloys and Compounds 375, nr 1-2 (lipiec 2004): 239–42. http://dx.doi.org/10.1016/j.jallcom.2003.11.155.

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Marina-Montes, César, Luis Vicente Pérez-Arribas, Jesús Anzano i Jorge O. Cáceres. "Local and Remote Sources of Airborne Suspended Particulate Matter in the Antarctic Region". Atmosphere 11, nr 4 (10.04.2020): 373. http://dx.doi.org/10.3390/atmos11040373.

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Quantification of suspended particulate matter (SPM) measurements—together with statistical tools, polar contour maps and backward air mass trajectory analyses—were implemented to better understand the main local and remote sources of contamination in this pristine region. Field campaigns were carried out during the austral summer of 2016–2017 at the “Gabriel de Castilla” Spanish Antarctic Research Station, located on Deception Island (South Shetland Islands, Antarctic). Aerosols were deposited in an air filter through a low-volume sampler and chemically analysed using Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) and Inductively Coupled Plasma-Atomic Emission Spectroscopy (ICP-AES). Elements such as Al, Ca, Fe, K, Mg, Na, P, S, Cu, Pb, Sr, Ti, Zn, Hf, Zr, V, As, Ti, Mn, Sn and Cr were identified. The statistical tools together with their correlations (Sr/Na, Al/Ti, Al/Mn, Al/Sr, Al/Pb, K/P) suggest a potentially significant role of terrestrial inputs for Al, Ti, Mn, Sr and Pb; marine environments for Sr and Na; and biological inputs for K and P. Polar contour graphical maps allowed reproducing wind maps, revealing the biological local distribution of K and P (penguin colony). Additionally, backward trajectory analysis confirmed previous affirmations and atmospheric air masses following the Antarctic circumpolar pattern.

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Jiao, Jiangang, Feng Han, Liandang Zhao, Jun Duan i Mengxi Wang. "Magnetite Geochemistry of the Jinchuan Ni-Cu-PGE Deposit, NW China: Implication for Its Ore-Forming Processes". Minerals 9, nr 10 (28.09.2019): 593. http://dx.doi.org/10.3390/min9100593.

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The Jinchuan Ni-Cu-PGE deposit is the single largest magmatic Ni-sulfide deposit in the world, with three different hypotheses on its ore-forming processes (e.g., in-situ sulfide segregation of sulfide-bearing magma, deep segregation with multiple injections of magma, and hydrothermal superimposition) mainly based on study of whole-rock geochemistry and isotopes (e.g., S-Sr-Nd-Hf). In this study, we mainly concentrated on magnetite textural and geochemical characteristics from different sulfide ores to clarify the genetic types and geochemical difference of the Jinchuan magnetite, and to explore a new credible ore-forming process by magnetite formation process when combined with detailed deposit geology. Three types of magnetite from massive and disseminated sulfide ores were observed by different textural analysis, and they were shown to have different genetic types (mainly in geochemistry) and trace elemental features. Type I magnetite is subhedral to anhedral from massive Ni- (or Fe-) and Cu-rich sulfide ores, with apparent magmatic origin, whereas Type II (dendritic or laminar crystals) and III magnetite (granular crystals as disseminated structures) from disseminated Cu-rich sulfide ores may have precipitated from late stage of melts evolved from a primitive Fe-rich and sulfide-bearing system with magmatic origin, but their geochemistry being typical of hydrothermal magnetite, videlicet, depletions of Ti (< 20 ppm), Al (< 51 ppm), Zr (0.01–0.57 ppm), Hf (0.03–0.06 ppm), Nb (0.01–0.14 ppm), and Ta (0.01–0.21 ppm). Such different types of magnetite can be clearly distinguished from concentrations and ratios of their trace elements, such as Ti, V, Co, Ni, Zn, Zr, Sn, Ga, and Ni/Cr. Those different types of Jinchuan magnetite crystallized from (evolved) sulfide-bearing systems and their geochemistries in trace elements are controlled mainly by evolution of ore-related systems and geochemical parameters (e.g., T and fO2), with the former playing a predominant role. Combining the previous literature with this study, we propose that the Jinchuan deposit formed by multiple pluses of sulfide-bearing magma during fractional crystallization, with the emplacing of more fractionated and sulfide-bearing magma during sulfide segregation playing a predominant role. During this multiple emplacement and evolving of sulfide-bearing systems, Type I magmatic magnetite crystallized from primitive and evolved Fe-rich MSS (monosulfide solid solution), while Type II and III magnetite crystallized from evolved Fe-rich MSS to Cu-rich ISS (intermediate solid solution) during sulfide fractionation, with those Type II and III magnetite having much higher Cu contents compared with that of Type I magnetite.

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Ángel Amorós a, José, Sandra Bravo, Francisco Jesús García Navarro, Francisco Pérez-de-los-Reyes, Francisco Sánchez-Ormeño, Jesús Gracía-Pradas, Raimundo Jiménez Ballesta i Pablo Higueras. "Zonificación de suelos vitícolas en Villanueva de Alcardete (Toledo, La Mancha, España) utilizando elementos traza." E3S Web of Conferences 50 (2018): 01025. http://dx.doi.org/10.1051/e3sconf/20185001025.

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Se realiza un estudio de suelos en el término municipal de Villanueva de Alcardete (Toledo, España) con la finalidad de señalar zonas homogéneas para el cultivo del viñedo. Se practicaron 15 calicatas en lugares representativos y se realizaron análisis físico químicos y clasificaciones edafológicas. También se consultaron fuentes clásicas de información pero se apunta como novedosa herramienta para la zonificación la composición geoquímica de los suelos. Se determinaron para cada perfil 11 elementos mayoritarios (Al, Ca, Fe, K, Na, Mg, Mn, P, S, Si, Ti) y 27 elementos traza (As, Ba, Ce, Co, Cr, Cs, Cu, Ga, Hf, La, Mo, Nb, Nd, Ni, Pb, Rb, Sc, Sn, Sr, Ta, Th, U, V, W, Y, Zn, Zr). Una vez estudiadas las fuentes de información y los datos obtenidos, el mapa de distribución del Estroncio (Sr) representa bastante bien las distintas zonas de suelos del área estudiada y puede ser utilizado (con las debidas comprobaciones y correcciones) para establecer lotes de suelos homogéneos.

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Chen, Xian, Xiaoming Sun, Zhongwei Wu, Yan Wang, Xiao Lin i Hongjun Chen. "Mineralogy and Geochemistry of Deep-Sea Sediments from the Ultraslow-Spreading Southwest Indian Ridge: Implications for Hydrothermal Input and Igneous Host Rock". Minerals 11, nr 2 (29.01.2021): 138. http://dx.doi.org/10.3390/min11020138.

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Detailed mineralogical and geochemical characteristics of typical surface sediments and hydrothermal deposits collected from the ultraslow-spreading Southwest Indian Ridge (SWIR) were studied by high-resolution XRD, SEM-EDS, XRF, and ICP-MS. The SWIR marine samples can be generally classified into two main categories: surface sediment (biogenic, volcanic) and hydrothermal-derived deposit; moreover, the surface sediment can be further classified into metalliferous and non-metalliferous based on the metalliferous sediment index (MSI). The chemical composition of biogenic sediment (mainly biogenic calcite) was characterized by elevated contents of Ca, Ba, Rb, Sr, Th, and light rare earth elements (LREE), while volcanic sediment (mainly volcanogenic debris) was relatively enriched in Mn, Mg, Al, Si, Ni, Cr, and high field strength elements (HFSEs). By contrast, the hydrothermal-derived deposit (mainly pyrite-marcasite, chalcopyrite-isocubanite, and low-temperature cherts) contained significantly higher contents of Fe, Cu, Zn, Pb, Mn, Co, Mo, Ag, and U. In addition, the metalliferous surface sediment contained a higher content of Cu, Mn, Fe, Co, Mo, Ba, and As. Compared with their different host (source) rock, the basalt-hosted marine sediments contained higher contents of Ti–Al–Zr–Sc–Hf and/or Mo–Ba–Ag; In contrast, the peridotite-hosted marine sediments were typically characterized by elevated concentrations of Mg–Cu–Ni–Cr and/or Co–Sn–Au. The differences in element enrichment and mineral composition between these sediment types were closely related to their sedimentary environments (e.g., near/far away from the vent sites) and inherited from their host (source) rock. Together with combinations of certain characteristic elements (such as Al–Fe–Mn and Si–Al–Mg), relict hydrothermal products, and diagnostic mineral tracers (e.g., nontronite, SiO2(bio), olivine, serpentine, talc, sepiolite, pyroxene, zeolite, etc.), it would be more effective to differentiate the host rock of deep-sea sediments and to detect a possible hydrothermal input.

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Mahne, Nastja, Miha Čekada i Matjaž Panjan. "Total and Differential Sputtering Yields Explored by SRIM Simulations". Coatings 12, nr 10 (13.10.2022): 1541. http://dx.doi.org/10.3390/coatings12101541.

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Total sputtering yield and spatial distributions of sputtered atoms are important for numerous deposition techniques. We performed SRIM (Stopping and Range of Ions in Matter) simulations to analyze the total sputtering yield and angular distribution of sputtered atoms for a range of single-element target materials. The simulations were conducted for normal argon ion incidence in the 300–1200 eV range and at an oblique angle for selected ion energies. We examined the total and differential sputtering yields for the transition metals in the periods 4–6 and groups 4–6 (Ti, V, Cr; Zr, Nb, Mo; Hf, Ta, and W) and group 11 (Cu, Ag, and Au) of the periodic table, and other materials that are relevant to sputtering (B and C; Al and Si). For the transition metals, the total sputtering yield increases with the group of the periodic table. The elements in group 4 (i.e., Ti, Zr, and Hf) have the lowest sputtering yield, while the elements in group 11 (i.e., Cu, Ag, and Au) exhibit the highest sputtering yield. The angular distribution of the sputtered atoms shows a cosine distribution for the transition metal atoms. The angular distribution of the sputtered atoms for the oblique ion incidence is more asymmetric for the lower ion energies, while for the higher ion energies, the atoms are sputtered more symmetrically. The symmetry also depends on the group of the periodic table and the atomic mass of the target material. The elements in group 11 show the most symmetric distribution, while the elements in group 4 experience the most asymmetric distribution. Furthermore, in an individual group, the distribution becomes more symmetric with heavier target elements. We also examined in detail the influence of the surface binding energy, atomic mass, and ion energy on the total sputtering yield. These parameters were analyzed with regard to the simplified analytical formula for the total sputtering yield, which was derived by Sigmund. This formula was modified by introducing a power fitting parameter, which accounts for the non-linear sputtering yield dependence on the ion energy. The equation provided good estimates for the total sputtering yield of the transition metals that were sputtered by argon ions with energies up to 1200 eV.

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Bozzolo, Guillermo, Hugo O. Mosca i Mariela F. del Grosso. "Energy of formation, lattice parameter and bulk modulus of (Ni,X)Ti alloys with X=Fe, Pd, Pt, Au, Al, Cu, Zr, Hf". Intermetallics 16, nr 5 (maj 2008): 668–75. http://dx.doi.org/10.1016/j.intermet.2008.02.003.

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Damonte, L. "Caractérisation par des techniques nucléaires de l'ordre à courte distance dans les verres métalliques massifs Zr-TM-Cu-Al-Ni (TM=Hf, Ti, Fe)". Annales de Chimie Science des Matériaux 27, nr 5 (październik 2002): 61–67. http://dx.doi.org/10.1016/s0151-9107(02)80046-0.

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Bahajroy, Mojtaba, i Saeed Taki. "Study of the mineralization potential of the intrusives around Valis (Tarom-Iran)". Earth Sciences Research Journal 18, nr 2 (16.03.2015): 123–29. http://dx.doi.org/10.15446/esrj.v18n2.44799.

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The study area is located in northwestern Iran in the central Iran zone, specifically the western Alborz sub-zone south of the Tarom-Hashtjin metallogenic zone. The exposed rock units in this area generally include Eocene volcanic rocks (lava flows and pyroclasts belonging to the Karaj formation) and Oligocene granitoid intrusive bodies. The intrusive bodies in the area have a petrographic composition of granite, syenite and monzonite and are mostly metaluminous. The dual characteristics of these intrusives (for example, the behavior of elements such as Rb, P, Ga/Al, Y/Nb, K/Na, and FeO/Fe2O3, the Rb/Nb ratios, the A/CNK molar ratios and the ACF and A/CNK-Fe2O3+FeO diagrams), some of which are consistent with the I nature and others with the S and A natures, show that the rocks are among hybrid granitoids and, in terms of the tectonic setting, lie within the WPG range. According to the Rb/Sr, Zr/Hf, K/Rb ratios, the granite melts that form the aforementioned bodies are not extremely evolved and have not undergone post magmatic activity, which would lead to mineralization. The Sm/Eu and Rb/Ba ratios and the behavior of Rb, Ba and Sr within the aforementioned granitoids show that the rocks are similar to average granitoids unrelated to Li, Be, Sn, W and Ta deposits; they fall within the range of barren granitoids but are partially fertile in Cu. ResumenEl área de este estudio está localizada en el noroeste de la zona central de Irán, específicamente en el oeste de la subzona de Alborz y al sur de la zona metalogénica de Tarom-Hashtjin. Las unidades de roca expuesta en esta área se clasifican generalmente como rocas volcánicas del Eoceno (flujos de lava y piroclastos pertenecientes a la formación Karaj) y como cuerpos granitoides intrusivos del Oligoceno. Los cuerpos intrusivos en el área tienen una composición petrográfica de granito, sienita y monzonita mayormente metaluminosa. Las características duales de estas intrusiones (por ejemplo, el comportamiento de de elementos como Rb, P, Ga/ Al, Y/Nb, K/Na, y Feo/Fe2O3, los índice de Rb/Nb, la proporción molar de los A/CNK y los diagramas ACF y A/CNK-Fe2O3+FeO), algunas de las cuales son consistentes con la índole I y otras con las índoles S y A, muestran que las rocas son granitoides híbridos y, en términos de orden tectónico, subyacen en la cadena WPG. De acuerdo con los índices Rb/Sr, Zr/Hf, K/Rb, los granitos fundieron la forma de los cuerpos sin desarrollarse completamente y sin registrar actividad magmática posterior, lo que llevó a la mineralización. Los índices Sm/Eu y Rb/Ba y el comportamiento del Rb, Ba y Sr al interior de los granitoides mencionados muestran que las rocas son similares al promedio de los granitoides no relacionados con los depósitos de Li, Be, Sn, W y Ta; estos incluyen en el rango de granitoides estériles, pero son parcialemente fértiles en Cu.

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Кропачева, Марья Юрьевна, Юлия Сергеевна Восель, Ксения Александровна Мезина, Дмитрий Константинович Белянин, Михаил Сергеевич Мельгунов i Ирина Владимировна Макарова. "ПЕРВЫЕ ДАННЫЕ О РАСПРЕДЕЛЕНИИ ИЗОТОПОВ, МАКРО- И МИКРОЭЛЕМЕНТОВ ИЗ АТМОСФЕРНЫХ ВЫПАДЕНИЙ В ЛИШАЙНИКАХ АРКТИЧЕСКИХ ТЕРРИТОРИЙ ЗАПАДНОЙ СИБИРИ". Bulletin of the Tomsk Polytechnic University Geo Assets Engineering 333, nr 9 (12.09.2022): 46–56. http://dx.doi.org/10.18799/24131830/2022/9/3683.

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Актуальность исследования обусловлена началом активного промышленного освоения арктических территорий России. Для корректной оценки техногенного воздействия необходимо знать региональные уровни геохимического фона, а также пути атмосферного переноса вещества. Лишайники широко используются в качестве биоиндикаторов не только антропогенного загрязнения, но и значимых природных процессов, к примеру, локального или глобального атмосферных переносов и биогеохимических процессов перераспределения элементов.Цель: определить содержания микро- и макроэлементов (Mg, Al, Si, P, K, Ca, Ti, V, Cr, Fe, Co, Ni, Cu, Zn, Sr, Zr, Cd, Ba, La, Ce, Eu, Pb, Nb, Mo, Nd, Hf, Ta, W, Th, U, Sn, REE), природных и искусственных изотопов (7Be, 210Pb, 137Cs) в лишайниках, а также их распределение между фракциями биомассы.Объекты: лишайники из лесотундры арктической зоны Западной Сибири: Ямало-Ненецкий Автономный округ, район Нового Уренгоя.Методы: фракционирование биомассы лишайника с выделением четырех фракций; определение стабильных элементов – ИСП-АЭС и ИСП-МС; определение природных и искусственных изотопов – гамма-спектрометрия с использованием колодезного детектора.Результаты. Содержания микро- и макроэлементов в лишайниках не показывают наличие значительного антропогенного воздействия. Все изученные элементы распределяются на две большие группы по характерным признакам распределения по фракциям биомассы лишайника. В первой группе элементы прочно связываются с биомассой лишайника за счет механического захвата частиц пыли из атмосферных выпадений. Элементы из второй группы испытывают физико-химическое воздействие со стороны лишайника и в различной степени распределяются по всем фракциям биомассы лишайника.

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Houska, J., i T. Kozak. "Relationships between the distribution of O atoms on partially oxidized metal (Al, Ag, Cu, Ti, Zr, Hf) surfaces and the adsorption energy: A density-functional theory study". Journal of Applied Physics 121, nr 22 (14.06.2017): 225303. http://dx.doi.org/10.1063/1.4985281.

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Zhang, Wei, i Akihisa Inoue. "Thermal Stability and Mechanical Properties of Cu-Based Bulk Glassy Alloys in Cu₅₀(Zr_1-xHf_x)₄₅Al₅ System". MATERIALS TRANSACTIONS 44, nr 10 (2003): 2220–23. http://dx.doi.org/10.2320/matertrans.44.2220.

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Bauluz Lazaro, B., C. Arenas Abad, C. Fernandez-Nieto i J. M. Gonzalez Lopez. "Mineralogy and geochemistry of Miocene deposits at Alcubierre Sierra, central sector of the Ebro Basin, Spain". Clay Minerals 29, nr 3 (wrzesień 1994): 391–400. http://dx.doi.org/10.1180/claymin.1994.029.3.10.

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AbstractTwo profiles in Miocene fluvio-lacustrine deposits consist of sandy, marly, lutitic and carbonatic levels constituted by variable percentages of quartz, calcite and clay minerals as major components, and feldspars, dolomite and occasionally gypsum and anhydrite as minor ones. The clay minerals are inherited and consist mostly of micas, with minor quantities of chlorites, pyrophyllites and kaolinites. The crystallochemical parameters of the micas indicate muscovitic compositions and their uniformity through both the different rocks and their silt and clay fractions suggest the same provenance source area, possibly located northward.Clay minerals concentrate preferentially Li, Sc, V, Cr, Co, Ni, Cu, Zn, Rb, Cs, Ba, Zr, Hf, Th, U and REE whereas the authigenic carbonates concentrate Mn and Sr. The Sc, Cr, Th, Y, Zr and REE values in clay minerals indicate that the provenance source area of these deposits was similar in composition to the average continental upper crust, probably as a result of sedimentary recycling processes.Zeolitic levels constituted by different proportions of analcime and smectite as major components outcrop at the top of the profiles. The analcimes show anhedral to euhedral morphologies, with grain-size ranging between 1 and 20 μm, and Si/Al ratios ranging from 2.2 to 2.5. The smectites are dioctahedral and beidellitic in composition. The zeolitic levels present significant chemical differences relative to the other ones, such as higher overall REE contents, more pronounced negative Eu anomalies and higher (La/Yb)n, Th/Sc and La/Sc ratios, suggesting a different provenance source area. Their chondrite-normalized REE patterns reflect the possibility that the starting materials were pyroclastic eruptive rocks originating from intracrustal partial melting. The variable analcime and smectite percentages are attributed to variations in H+/(Na+ + K+) and K+/(Na + Ca2+ + Mg2+) activity ratios and silica and water activities in the pore-waters during diagenetic processes.

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Nemchinova, N. V., i A. A. Zaitseva. "Improving the quality of metallurgical-grade silicon by acid leaching". iPolytech Journal 27, nr 2 (7.07.2023): 436–48. http://dx.doi.org/10.21285/1814-3520-2023-2-436-448.

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This work deals with the problem of hydrometallurgical refining of metallurgical-grade silicon. Samples of metallurgical-grade silicon after oxidative refining from JSC Silicon, RUSAL (Shelekhov, Irkutsk Oblast, Russia) were subjected to X-ray fluorescence and electron microprobe analysis. The conducted elemental analysis determined their following composition, wt%: Al – 0.53, Fe – 0.6094, Ti – 0.0491, Ca – 0.0628, V – 0.0066, Cr – 0.002, Mn – 0.014, Cu – 0.003, P – 0.010, Ba – 0.007, Ni – 0.007, and Zn – 0.002. The examined samples were found to comprise the following intermetallic compounds: AlFeSi2 (with an admixture of Ca), FeSi2 (with an admixture of Al), and FeSi2Ti (with an admixture of Zr). In order to purify silicon from impurities, 10% H2SO2, HCl, HNO3, as well as 4% HF in different ratios were used as solvents. The feasibility of interactions between the intermetallic compounds and the selected solvents was assessed by calculating changes in the Gibbs energy, which had negative values. Experiments on impurity leaching were carried out using silicon samples with a particle size of –200 µm under constant stirring with a magnetic stirrer under the temperature of 600С, the liquid-to-solid ratio of 5:1, and the leaching duration of 60 min. The highest degree of silicon purification (86.85%) was achieved under leaching with a mixture of sulfuric and hydrofluoric acids in a ratio of 1:1. The use of a mixture of sulfuric and hydrochloric acids at a ratio of 1:3 resulted in the silicon purification of 41.48%. Thus, optimal solvents allowing the maximum purification of silicon from impurities were determined.

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Saleh, Ali H., Mohamed Gad, Moataz M. Khalifa, Salah Elsayed, Farahat S. Moghanm, Adel M. Ghoneim, Subhan Danish, Rahul Datta, Moustapha E. Moustapha i Magda M. Abou El-Safa. "Environmental Pollution Indices and Multivariate Modeling Approaches for Assessing the Potentially Harmful Elements in Bottom Sediments of Qaroun Lake, Egypt". Journal of Marine Science and Engineering 9, nr 12 (16.12.2021): 1443. http://dx.doi.org/10.3390/jmse9121443.

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This research intends to offer a scientific foundation for environmental monitoring and early warning which will aid in the environmental protection management of Qaroun Lake. Qaroun Lake is increasingly influenced by untreated wastewater discharge from many anthropogenic activities, making it vulnerable to pollution. For that, six environmental pollution indices, namely contamination factor (Cf), enrichment factor (EF), geo-accumulation index (Igeo), degree of contamination (Dc), pollution load index (PLI), and potential ecological risk index (RI), were utilized to assess the bottom sediment and to determine the different geo-environmental variables affecting the lake system. Cluster analysis (CA), and principal component analysis (PCA) were used to explore the potential pollution sources of heavy metal. Moreover, the efficiency of partial least-square regression (PLSR) and multiple linear regression (MLR) were tested to assess the Dc, PLI, and RI depending on the selected elements. The sediment samples were carefully collected from 16 locations of Qaroun Lake in two investigated years in 2018 and 2019. Total concentrations of Al, As, Ba, Cd, Co, Cr, Cu, Fe, Ga, Hf, Li, Mg, Mn, Mo, Ni, P, Pb, Sb, Se, Zn, and Zr were quantified using inductively coupled plasma mass spectra (ICP-MS). According to the Cf, EF, and Igeo results, As, Cd, Ga, Hf, P, Sb, Se, and Zr demonstrated significant enrichment in sediment and were derived from anthropogenic sources. According to Dc results, all collected samples were categorized under a very high degree of contamination. Further, the results of RI showed that the lake is at very high ecological risk. Meanwhile, the PLI data indicated 59% of lake was polluted and 41% had PLI < 1. The PLSR and MLR models based on studied elements presented the highest efficiency as alternative approaches to assess the Dc, PLI, and RI of sediments. For examples, the validation (Val.) models presented the best performance of these indices, with R2val = 0.948–0.989 and with model accuracy ACCv = 0.984–0.999 for PLSR, and with R2val = 0.760–0.979 and with ACCv = 0.867–0.984 for MLR. Both models for Dc, PLI, and RI showed that there was no clear overfitting or underfitting between measuring, calibrating, and validating datasets. Finally, the combinations of Cf, EF, Igeo, PLI, Dc, RI, CA, PCA, PLSR, and MLR approaches represent valuable and applicable methods for assessing the risk of potentially harmful elemental contamination in the sediment of Qaroun Lake.

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Sun, Jungang, Ting Liang, Hongying Li, Kun Yan, Yinyin Chao i Zhanbin Wang. "Implications for Metallogenesis and Tectonic Evolution of Ore-Hosting Granodiorite Porphyry in the Tongkuangyu Cu Deposit, North China Craton: Evidence from Geochemistry, Zircon U-Pb Chronology, and Hf Isotopes". Minerals 12, nr 2 (21.02.2022): 273. http://dx.doi.org/10.3390/min12020273.

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The Tongkuangyu copper deposit in Zhongtiaoshan at the southern margin of the North China Craton is one of the oldest porphyry Cu deposits in the world and its metallogenesis and tectonic evolution have been debated. Here, porphyritic intrusion geochemical and geochronological data are reported to identify the diagenetic age, mineralization, tectonic setting, and evolution of the deposit. Geochemical data show that granodiorite porphyry is a peraluminous rock, with low concentrations of Fe (~3.99%) and Ti (~0.29%) and high concentrations of alkali (~6.13%) and high Al (~15.42%) and Mg numbers (~51). The rocks show comparative enrichment of Na, K, and Mg; higher La/Yb ratios, no significant Eu anomaly, and obvious Nb–Ta–Ti negative anomaly, showing similar geochemical characteristics to Archean TTG and sanukitoid. ΣREE vary greatly, ranging from 33.47 × 10−6 to 277.81 × 10−6 (average 137.09 × 10−6). The characteristics of REE show obvious fractionation of LREE and HREE, enrichment of LREE, and depletion of HREE. Some of the LREE (La and Ce) and LILE (K, Rb, and Ba) are enriched, but some of the LILE (Th and U) are depleted. In addition, some of the HFSE (Nb, Ta, P, and Ti) are depleted while some (Zr and Hf) are enriched. High precision LA–MC–ICP MS zircon U–Pb dating yield concordant ages of 2159 ± 19 Ma, which is broadly coeval with ore formation (~2.1 Ga) in the area. Zircon εHf(t) values range from −3.8 to 1.13, with a model age of 2778 to 2959 Ma, indicating that the formation of porphyry is related to the partial melting of Archean crust (~2.7 Ga) with a minor amount of mantle material added. Tongkuangyu granodiorite porphyry formed in the tectonic setting of the post-orogenic extension in the Paleoproterozoic, and Tongkuangyu Cu deposit may be related to the extension of the North China Craton in the Paleoproterozoic.

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Manasypov, Rinat M., Artem G. Lim, Ivan V. Kriсkov, Liudmila S. Shirokova, Sergey N. Vorobyev, Sergey N. Kirpotin i Oleg S. Pokrovsky. "Spatial and Seasonal Variations of C, Nutrient, and Metal Concentration in Thermokarst Lakes of Western Siberia Across a Permafrost Gradient". Water 12, nr 6 (26.06.2020): 1830. http://dx.doi.org/10.3390/w12061830.

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Thermokarst lakes and ponds formed due to thawing of frozen peat in high-latitude lowlands are very dynamic and environmentally important aquatic systems that play a key role in controlling C emission to atmosphere and organic carbon (OC), nutrient, and metal lateral export to rivers and streams. However, despite the importance of thermokarst lakes in assessing biogeochemical functioning of permafrost peatlands in response to climate warming and permafrost thaw, spatial (lake size, permafrost zone) and temporal (seasonal) variations in thermokarst lake hydrochemistry remain very poorly studied. Here, we used unprecedented spatial coverage (isolated, sporadic, discontinuous, and continuous permafrost zone of the western Siberia Lowland) of 67 lakes ranging in size from 102 to 105 m2 for sampling during three main hydrological periods of the year: spring flood, summer baseflow, and autumn time before ice-on. We demonstrate a systematic, all-season decrease in the concentration of dissolved OC (DOC) and an increase in SO4, N-NO3, and some metal (Mn, Co, Cu, Mo, Sr, U, Sb) concentration with an increase in lake surface area, depending on the type of the permafrost zone. These features are interpreted as a combination of (i) OC and organically bound metal leaching from peat at the lake shore, via abrasion and delivery of these compounds by suprapermafrost flow, and (ii) deep groundwater feeding of large lakes (especially visible in the continuous permafrost zone). Analyses of lake water chemical composition across the permafrost gradient allowed a first-order empirical prediction of lake hydrochemical changes in the case of climate warming and permafrost thaw, employing a substituting space for time scenario. The permafrost boundary shift northward may decrease the concentrations and pools of dissolved inorganic carbon (DIC), Li, B, Mg, K, Ca, Sr, Ba, Ni, Cu, As, Rb, Mo, Sr, Y, Zr, rare Earth elements (REEs), Th, and U by a factor of 2–5 in the continuous permafrost zone, but increase the concentrations of CH4, DOC, NH4, Cd, Sb, and Pb by a factor of 2–3. In contrast, the shift of the sporadic to isolated zone may produce a 2–5-fold decrease in CH4, DOC, NH4, Al, P, Ti, Cr, Ni, Ga, Zr, Nb, Cs, REEs, Hf, Th, and U. The exact magnitude of this response will, however, be strongly seasonally dependent, with the largest effects observable during baseflow seasons.

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Orlova, Albina I., i Michael I. Ojovan. "Ceramic Mineral Waste-Forms for Nuclear Waste Immobilization". Materials 12, nr 16 (19.08.2019): 2638. http://dx.doi.org/10.3390/ma12162638.

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Crystalline ceramics are intensively investigated as effective materials in various nuclear energy applications, such as inert matrix and accident tolerant fuels and nuclear waste immobilization. This paper presents an analysis of the current status of work in this field of material sciences. We have considered inorganic materials characterized by different structures, including simple oxides with fluorite structure, complex oxides (pyrochlore, murataite, zirconolite, perovskite, hollandite, garnet, crichtonite, freudenbergite, and P-pollucite), simple silicates (zircon/thorite/coffinite, titanite (sphen), britholite), framework silicates (zeolite, pollucite, nepheline /leucite, sodalite, cancrinite, micas structures), phosphates (monazite, xenotime, apatite, kosnarite (NZP), langbeinite, thorium phosphate diphosphate, struvite, meta-ankoleite), and aluminates with a magnetoplumbite structure. These materials can contain in their composition various cations in different combinations and ratios: Li–Cs, Tl, Ag, Be–Ba, Pb, Mn, Co, Ni, Cu, Cd, B, Al, Fe, Ga, Sc, Cr, V, Sb, Nb, Ta, La, Ce, rare-earth elements (REEs), Si, Ti, Zr, Hf, Sn, Bi, Nb, Th, U, Np, Pu, Am and Cm. They can be prepared in the form of powders, including nano-powders, as well as in form of monolith (bulk) ceramics. To produce ceramics, cold pressing and sintering (frittage), hot pressing, hot isostatic pressing and spark plasma sintering (SPS) can be used. The SPS method is now considered as one of most promising in applications with actual radioactive substances, enabling a densification of up to 98–99.9% to be achieved in a few minutes. Characteristics of the structures obtained (e.g., syngony, unit cell parameters, drawings) are described based upon an analysis of 462 publications.

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Yang, Haifeng, Deying Wang, Feilong Wang, Yanfei Gao, Guomin Tang, Youjun Tang i Peng Sun. "Differential Enrichment of Trace and Major Elements in Biodegraded Oil: A Case Study from Bohai Bay Basin, China". Processes 11, nr 4 (11.04.2023): 1176. http://dx.doi.org/10.3390/pr11041176.

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Inorganic elements in crude oil have been used in the reconstruction of the sedimentary environment and oil–oil (source) correlations; however, the effect of biodegradation on these elements has not been investigated sufficiently. In this study, 14 crude oils from the Miaoxi Sag of the Bohai Bay Basin, eastern China, were analyzed using molecular markers, trace elements, and major elements to determine the effect of biodegradation on inorganic elements. The molecular markers indicated that the oils are in the low maturity stage and are derived from similar parent materials in lacustrine source rocks. The high-sulfur oil came from a more reductive and saltier environment compared with the low-sulfur oil. The oils were subjected to varying degrees of biodegradation. The concentrations of Mg, Ca, Mn, Fe, Be, Sc, Rb, Sr, Zr, Pb, Th, and U increased significantly throughout the biodegradation process, while the concentrations of Na, K, Ti, Al, Cr, Zn, Cs, Nb, Ba, Hf, and Tl increased considerably only during the intense biodegradation stage (PM < 4). The concentrations of P, Li, V, Co, Ni, Cu, Ga, Sn, and Ta were not correlated with the level of biodegradation. The V/Ni, V/Co, Ni/Co, Cr/V, Sc/V, and Th/U ratios were affected by biodegradation when PM ≥ 4. Several ratios, including Mg/P, Ca/P, Mn/P, and Fe/P, are proposed as favorable indicators of the level of biodegradation. Differential enrichment of these elements is associated with the effects of organic acids generated by biodegradation on the oil–water–rock interactions in the reservoir.

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