Статті в журналах: "Co-Ni-Al- Mo-Ta"

1

Inoue, Akihisa, Bao Long Shen, and Akira Takeuchi. "Syntheses and Applications of Fe-, Co-, Ni- and Cu-Based Bulk Glassy Alloys." Materials Science Forum 539-543 (March 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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2

Park, Si-Jun, Seong-Moon Seo, Young-Soo Yoo, Hi-Won Jeong, and HeeJin Jang. "Statistical Study of the Effects of the Composition on the Oxidation Resistance of Ni-Based Superalloys." Journal of Nanomaterials 2015 (2015): 1–11. http://dx.doi.org/10.1155/2015/929546.

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The effects of alloying elements (Co, Cr, Mo, W, Al, Ti, and Ta) on the oxidation resistance of Ni-based superalloys are studied using the Response Surface Methodology (RSM). The statistical analysis showed that Al and Ta generally improve the oxidation resistance of the alloy, whereas Ti and Mo degrade the oxidation resistance. Co, Cr, and W did not alter oxidation rate significantly when examined by the mass gain averaged for all model alloys. However, it is remarkable that the degree of the effects of alloying elements varied with the concentration of other elements. Further, the effect of each element was sometimes found to be reversed for alloy groups specified by the concentration of another element.

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3

Hahn, Junhee, Xiao Xiao, and Dong Bok Lee. "Oxidation of Ni-Cr-Co-Al-Mo-Ti-Re-Ta-W-Ru Single Crystals at 1000 ^oC in Air." Korean Journal of Metals and Materials 58, no. 4 (April 5, 2020): 234–46. http://dx.doi.org/10.3365/kjmm.2020.58.4.234.

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Three kinds of Ni-based single crystals with the compositions of 63.8Ni-7.5Cr-5.1Co-4.8Al-1.9Mo- 0.9Ti-3Re-11.8Ta-1.2W, 61.4Ni-7.4Cr-5Co-4.8Al-1.8Mo-0.9Ti-3.1Re-11.6Ta-4W, and 60.9Ni-7.5Cr-5Co-4.8Al- 2Mo-1Ti-2.9Re-10.9Ta-1.2W-3.8Ru, in wt%, were cast in a Bridgman furnace. In the cast alloys, Cr, Co, Re, Mo, W, and Ru became microsegregated in dendrites consisting of γ-Ni, while Ni, Ta, and Al microsegregated in interdendrites consisting of eutectic γ/γ . The cast alloys were oxidized at 1000 oC up to 275 h in air to study the effect of alloying elements on high-temperature oxidation. The oxide scales consisted primarily of CrTaO4, with some NiCr2O4, NiO, and α-Al2O3. The oxidation resistance was dependent on the formation and continuity of the α-Al2O3 scale. Ta and W were beneficial, while Ru was harmful in improving the oxidation resistance. The selective oxidation of Al in dendrites led to the formation of thin, uniform α-Al2O3 scales, i.e., uniform oxidation. The competitive oxidation of active elements such as Al, Ti, and Ta in interdendrites led to the formation of porous, crack-susceptible oxide nodules, i.e., nodular oxidation. Less active elements such as Ru, Re, Ni, Co, Mo, W, and Cr tended to enrich in the vicinity of the oxide nodules. The oxidation progressed through the outward diffusion of cations and the inward diffusion of oxygen. This inward diffusion formed internal alumina islands, beneath the oxide scale.

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4

Yamanaka, Syuki, Ken-ichi Ikeda, and Seiji Miura. "Effect of Multi-Elements Substitution on the Mechanical Properties of Intermetallic Compound." MRS Advances 4, no. 25-26 (2019): 1497–502. http://dx.doi.org/10.1557/adv.2019.119.

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ABSTRACTIt is well known that various elements substitute for a certain sub-lattice of intermetallic compounds. There have been various experimental investigations of the effects of substituted elements on mechanical properties, however, there are few reports describing the effects of multi-element substitution. In the present study, L12-type compounds A3B (Ni3Al and Co3(Al,W)) were selected as model compounds because their substitution behavior is well known. It was reported that various elements such as Ni, Co, Cu, Pd and Pt occupy the A-site, whereas Al, Si, Ga, Ge, Ti, V, Nb, Ta, Mo, and W occupy the B-site. These elements are expected to introduce local lattice distortion, which may affect the motion of dislocations over a wide range of temperatures. Several alloys composed of five or more elements including Ni, Co, Al, Mo, and W, were prepared using an Ar-arc melting machine and heat-treated. Several alloys were found to include an (Ni, Co)3(Al, Mo, W, …)-L12 compound as a constituent phase. The nano-hardness of these L12 phases was higher than that of the high-strength Co3(Al,W)-L12 compound, confirming that multi-element substitution is an effective way to improve the mechanical properties of an intermetallic compound without decreasing the phase stability.

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5

Singh, Mahander Pratap, Emmanuel Femi Olu, Prafull Pandey, and Kamanio Chattopadhyay. "Thermophysical and magnetic properties of Co-Ni-Mo-Al-Ta class of tungsten free Co-based superalloys." Journal of Alloys and Compounds 879 (October 2021): 160379. http://dx.doi.org/10.1016/j.jallcom.2021.160379.

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6

Sanin, Vitaliy V., Yury Yu Kaplansky, Maksym I. Aheiev, Evgeny A. Levashov, Mikhail I. Petrzhik, Marina Ya Bychkova, Andrey V. Samokhin, Andrey A. Fadeev, and Vladimir N. Sanin. "Structure and Properties of Heat-Resistant Alloys NiAl–Cr–Co–X (X = La, Mo, Zr, Ta, Re) and Fabrication of Powders for Additive Manufacturing." Materials 14, no. 12 (June 8, 2021): 3144. http://dx.doi.org/10.3390/ma14123144.

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The NiAl–Cr–Co–X alloys were produced by centrifugal self-propagating high-temperature synthesis (SHS) casting. The effects of dopants X = La, Mo, Zr, Ta, and Re on combustion, as well as the phase composition, structure, and properties of the resulting cast alloys, have been studied. The greatest improvement in overall properties was achieved when the alloys were co-doped with 15% Mo and 1.5% Re. By forming a ductile matrix, molybdenum enhanced strength characteristics up to the values σucs = 1604 ± 80 MPa, σys = 1520 ± 80 MPa, and εpd = 0.79%, while annealing at T = 1250 ℃ and t = 180 min improved strength characteristics to the following level: σucs = 1800 ± 80 MPa, σys = 1670 ± 80 MPa, and εpd = 1.58%. Rhenium modified the structure of the alloy and further improved its properties. The mechanical properties of the NiAl, ZrNi5, Ni0.92Ta0.08, (Al,Ta)Ni3, and Al(Re,Ni)3 phases were determined by nanoindentation. The three-level hierarchical structure of the NiAl–Cr–Co+15%Mo alloy was identified. The optimal plasma treatment regime was identified, and narrow-fraction powders (fraction 8–27 µm) characterized by 95% degree of spheroidization and the content of nanosized fraction <5% were obtained.

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7

Rogachev, S. A., A. S. Rogachev, and M. I. Alymov. "Estimation of the critical vitrification rate of pure metals using molecular dynamics simulation." Доклады Академии наук 486, no. 2 (May 27, 2019): 168–72. http://dx.doi.org/10.31857/s0869-56524862168-172.

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A molecular dynamics simulation method was applied for estimation of critical cooling rates (vc) that required for amorphization of pure metals: Mg, Al, Ti, Fe, Co, Ni, Cu, Zr, Mo, Pd, Ag, Ta, W, Pt, Au, and Pb. The range of values vc was found to be from 7.9 × 1011 K/s for Al to 3.8 × 1013 K/s for Zr. The atomic structure obtained at different cooling rates is described. A dependence of the specific volume on temperature was investigated both during the amorphization and crystallization processes. The modelling shows, which metals have the highest temperature range of long-term stability of the amorphous phase (Fe, Mo, Ta, W). Estimates were given for the maximum radius of a melt drop that can be cooled at a rate of vc. The obtained simulation results were compared with available experimental data.

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8

Zhang, Yu, Qing Wang, Hong-Gang Dong, Chuang Dong, Hong-Yu Zhang, and Xiao-Feng Sun. "High-Temperature Structural Stabilities of Ni-Based Single-Crystal Superalloys Ni–Co–Cr–Mo–W–Al–Ti–Ta with Varying Co Contents." Acta Metallurgica Sinica (English Letters) 31, no. 2 (November 17, 2017): 127–33. http://dx.doi.org/10.1007/s40195-017-0678-0.

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9

Prut, V. V. "High pressure ruby scale." Izvestiya vysshikh uchebnykh zavedenii. Fizika, no. 7 (2022): 99–105. http://dx.doi.org/10.17223/00213411/65/7/99.

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A new calibration of the ruby scale is proposed, based on the Hugoniot equations and static isotherms at high pressures of a number of substances: Al, Co, Ni, Cu, Zn, Mo, Ag, Ta, W, Pt, Au. New functional dependencies have been identified P (λ). Errors arising because of errors in experimental shock and static data and the use of various functional dependences of equations of state are analyzed. The new scale is compared with all 14 published calibrations.

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10

Prüβner, K., K. B. Alexander, B. A. Pint, P. F. Tortorelli, and I. G. Wright. "Interfacial Segregation in Oxide Scales on Nicrai-Based Alloys." Microscopy and Microanalysis 3, S2 (August 1997): 785–86. http://dx.doi.org/10.1017/s1431927600010813.

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Previous studies addressing the segregation of reactive elements in protective oxide scales and their beneficial effect on scale adhesion have primarily concentrated on primary alumina-formers (e.g. β-NiAl + FeCrAl).In our study the oxidation behaviour of three NiCrAl alloys, which form complex scales was studied in air at 1423 K and at 1473 K, both in isothermal (100 h) and in cyclic oxidation (100 x lh). The composition (in at.-%) of these alloys is the following: General Electric alloy René N5 (64.9 Ni, 7.8 Cr, 13.9 Al, 0.1 Fe, 2.1 Ta, 0.05 Hf, 1.6 W, 1.0 Re, 0.15 Si, 7.3 Co, 0.9 Mo, 0.003 Y, 0.003 Zr, 4 ppm S, 0.25 C), Ni-7Cr-6.5Al+Y (80.1 Ni, 7.2 Cr, 12.5 Al, 0.01 Fe, 0.14 Si, 0.012 Y, 18 ppm S, 0.05 C) and Ni-10Cr-10Al+Y (71.2 Ni, 9.9 Cr, 18.8 Al, 0.01 Fe, 0.02 Si, 0.041 Y, 16 ppm S, 0.04 C).

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11

Kommel, Lembit A., and Boris B. Straumal. "Diffusion in SC Ni-Base Superalloy under Viscoplastic Deformation." Defect and Diffusion Forum 297-301 (April 2010): 1340–45. http://dx.doi.org/10.4028/www.scientific.net/ddf.297-301.1340.

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Deformation-enhanced diffusion in single-crystalline Ni-based superalloy specimens have been investigated under the conditions of hard cyclic viscoplastic tension-compression deformation. The chemical composition of phases before and after cyclic deformation was investigated by filed-emission scanning electron microscopy. At low strain amplitude values (0-0.05%; 0-0.2%; 0-0.5%) the material shows upscaled viscoelastic behavior and microstructural stability. At the increase of strain amplitude in the γ+γ’-phase (0-1%), the Ni, Re and Co content decreases, whereas Al and Mo content increases significantly. On the contrary, in the single γ’-phase area, the Ni and Co content was increased, which was accompanied by a decrease of Nb, Cr, Ta and Al content. The length of dendrite arms was significantly decreased as compared to primary dendrite arms and γ+γ’-rafts were formed parallel to the stress axis direction. As a result of the deformation-enhanced, diffusion the necking of dendrites accompanied with longitudinal cracking by the dendrite axis and cross-sectional radial cracking by interdendritic region of single crystalline specimen occurs.

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12

Liu, Dengyu, Qingqing Ding, Qian Zhou, Dingxin Zhou, Xiao Wei, Xinbao Zhao, Ze Zhang, and Hongbin Bei. "Microstructure, Mechanical Properties and Thermal Stability of Ni-Based Single Crystal Superalloys with Low Specific Weight." Crystals 13, no. 4 (April 2, 2023): 610. http://dx.doi.org/10.3390/cryst13040610.

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Ni-based single crystal (SX) superalloy with low specific weight is vital for developing aero engines with a high strength-to-weight ratio. Based on an alloy system with 3 wt.% Re but without W, namely Ni-Co-Cr-Mo-Ta-Re-Al-Ti, a specific weight below 8.4 g/cm3 has been achieved. To reveal the relationship among the composition, mechanical properties, and thermal stability of Ni-based SX superalloys, SXs with desirable microstructures are fabricated. Tensile tests revealed that the SX alloys have comparable strength to commercial second-generation SX CMSX-4 (3 wt.% Re and 6 wt.% W) and Rene′ N5 alloys (3 wt.% Re and 5 wt.% W) above 800 °C. Moreover, the elongation to fracture (EF) below 850 °C (>20%) is better than that of those two commercial SX superalloys. During thermal exposure at 1050 °C for up to 500 h, the topological close-packed (TCP) phase does not appear, indicating excellent phase stability. Decreasing Al concentration increases the resistance of γ′ rafting and replacing 1 wt.% Ti with 3 wt.% Ta is beneficial to the stability of the shape and size of γ′ phase during thermal exposure. The current work might provide scientific insights for developing Ni-based SX superalloys with low specific weight.

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13

Yu, Zhu Huan, and Jun Feng Qiang. "Microsegregation Behavior of Single Crystal Superalloy." Advanced Materials Research 983 (June 2014): 121–26. http://dx.doi.org/10.4028/www.scientific.net/amr.983.121.

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The major advancements in some mechanical properties of single crystal superalloys can be attributed to the carbon addition. The present study investigated the effect of carbon addition levels on the microsegregation behavior of single crystal superalloys. Quantitatative partitioning results indicated that typical single crystal superalloy segregation behavior for some elements such as W, Ni, Co, are all towards the dendrite core regions, while for elements of Al, Mo, Ta, Ti, Cr, partition towards the interdendrite regions. For all the alloys studied, the baseline alloy showed the most severe segregation degree, while the no carbon alloy the slightest. Furthermore, the segregation behavior of Ti and Ta were affected by the carbon additions, and that of W was greatly affected by the carbon levels.

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14

Nikonenko, E. L., Natalya A. Popova та N. A. Koneva. "Structure and Phase Composition of Ni-Al-Co-Mе-Based Alloy Containing Rhenium and Ruthenium". Solid State Phenomena 303 (травень 2020): 111–17. http://dx.doi.org/10.4028/www.scientific.net/ssp.303.111.

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The present study was conducted by transmission electron microscopy (TEM) in order to investigate the structure of multicomponent nickel-based alloy obtained by directional solidification and change in its phase composition at high-temperature annealing. All states of the alloy possessed monocrystalline structure with [001] orientation. The alloy under study contained other elements apart from Ni, such as: Al, Co, and also Mo, Cr, W, Ta, Re, and Ru. The alloy was investigated in three states after annealing for: 1) 118 h; 2) 372 h; 3) 1274 h at 1000°С. The basic phases that form the alloy were γ and γ′. In the state after annealing for 118 h Al6(Re,Ru) phase was observed in an insignificant amount. After longer high temperature annealing new phases occurred, such as σ-phase and δ-phase, Laves phase. The structures occurring during annealing can be classified into four types: 1) quasi-cuboids, 2) anisotropic stripe structures, 3) anisotropic structures of striped type with σ-phase separation, 4) structureless zones with large two-phase areas.

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15

Hall, E. L., and M. R. Jackson. "Microstructural Characterization of Rapidly Solidified Carbide-Containing Ni-Base Superalloys." Proceedings, annual meeting, Electron Microscopy Society of America 43 (August 1985): 48–49. http://dx.doi.org/10.1017/s0424820100117315.

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The temperature capability of nickel-base superalloys which are used in aircraft turbines may be able to be extended if novel microstructures can be produced in these materials by rapid solidification. The primary goal of these efforts is to achieve a fine dispersion of small precipitates which are stable at high temperature in the alloys. One class of alloys which seem particularly promising are the eutectic superalloys, which solidify via a eutectic reaction in which a γ- γ’ matrix containing MC carbides is formed. For this investigation, alloys which contained either Ta, Ti, or V as the primary carbide former were studied. In all cases, the base alloy consisted of Ni-4%Co-4%Cr-5.5%Al-2%Mo-3%W-1.5%Re-0.3%C in weight percent. The alloys additionally contained either 9% Ta, 5.5% Ti, or 4.5% V (subsequently referred to as alloys A, B, and C, respectively). The alloys were rapidly solidified by melt-spinning in vacuum.

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16

Huang, Zhao Hui, Yong Ning Tan, Xi Hong Zhao, Jian Ping Li, and Qiang Zhang. "High Temperature Oxidation Resistance of Two Ni(Co)CrAlYSi(Hf) Overlay Coatings." Materials Science Forum 539-543 (March 2007): 1146–52. http://dx.doi.org/10.4028/www.scientific.net/msf.539-543.1146.

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Two MCrAlY overlay coatings (NiCrAlYSi and NiCoCrAlYHf) were deposited on a DS superalloy of Ni-Al-Cr-Co-W-Mo-Ta-Hf system by vacuum arc deposition method. The two coatings show a good protection for the DS superalloy during the isothermal oxidation test at 1150 for 100 h. A continuous alumina-based scale was formed at the surfaces of the coated specimens after oxidation. Y2O3, NiO and SiO2 are also detectable in the oxide scale. For the Hf-bearing coating, some HfO2 particles exist at the interface between the coating and the substrate. But after the cyclic thermal oxidation at 1100°C, the Hf-free coating exhibited better oxidation resisitance than the Hf-bearing coating. The HfO2 blocks between the coat and the substrate may be the crack initiation which leads to the failure of the coating.

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17

Das, Saurabh Mohan, Mahander Pratap Singh та Kamanio Chattopadhyay. "Evolution of oxides and their microstructures at 800°C in a γ-γ’ stabilised Co-Ni-Al-Mo-Ta superalloy". Corrosion Science 155 (липень 2019): 46–54. http://dx.doi.org/10.1016/j.corsci.2019.02.013.

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18

Babalola, Bukola Joseph, Mxolisi Brendon Shongwe, Nthabiseng Maledi, Samson Olaitan Jeje, Olusoji Oluremi Ayodele, Azeez Rominiyi Lawan, and Peter Apata Olubambi. "Effect of Nanocrystalline Nickel Powder and Co, Mo, Ta, and Al Additions on Isothermal Oxidation Behavior of Ni–17Cr Alloy." Metallography, Microstructure, and Analysis 9, no. 1 (January 24, 2020): 75–85. http://dx.doi.org/10.1007/s13632-020-00614-9.

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19

Ofori, A. P., та C. J. Humphreys. "Atomic Site Occupancy of Platinum Group Metals in the γ’ (Ll2) Phase of a γ-γ’ Complex Nickel Base Superalloy Using Alchemi (Atomic Location by Channnelling Enhanced Microanalysis)". Microscopy and Microanalysis 7, S2 (серпень 2001): 346–47. http://dx.doi.org/10.1017/s143192760002780x.

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Nickel-base superalloys (NBSAs) have remarkable mechanical properties (and corrosion resistance) at elevated temperatures. Single crystal NBSAs have found major use as turbine blades in aeroengines, where there is a large world market because the turbine blades have to be replaced at regular intervals. in order to develop engines with higher efficiency, considerable efforts are being devoted to enhance the temperature capabilities of superalloys. The two phase γ-γ’ structure that is crucial to NBSA characteristics is primarily produced by the presence of Al in combination with Ni: above a critical concentration the Ll2 γ’ phase based on Ni3Al precipitates out of the γ Ni-base solution. However, superalloys usually contain many other alloying elements such as Cr, Co, Mo, W and Ta to enhance strength and impart higher temperature performance. Among these alloying additions, much attention has recently been paid to Re because of its contribution to the improvement of both creep and corrosion properties.

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20

Chaligava, Omari, Igor Nikolaev, Khetag Khetagurov, Yulia Lavrinenko, Anvar Bazaev, Marina Frontasyeva, Konstantin Vergel, and Dmitry Grozdov. "First Results on Moss Biomonitoring of Trace Elements in the Central Part of Georgia, Caucasus." Atmosphere 12, no. 3 (February 28, 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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21

Ol’shanetskii, V. E., and A. A. Glotka. "Distribution of Elements Within Carbides of Multicomponent Alloys of the Ni – Cr – Co – Al – W – Re – Ta – Mo – Nb – C System." Metal Science and Heat Treatment 63, no. 5-6 (September 2021): 318–26. http://dx.doi.org/10.1007/s11041-021-00689-3.

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22

Dobrovská, Jana, Simona Dočekalová, Věra Dobrovská, and Karel Stránský. "Effect of Cooling Rate on Structural and Chemical Microheterogeneity of IN 738LC Nickel Based Superalloy." Solid State Phenomena 138 (March 2008): 201–8. http://dx.doi.org/10.4028/www.scientific.net/ssp.138.201.

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The paper deals with the effect of cooling rate on solidification behavior of IN 738LC nickel based superalloy and on resulting structural and chemical microheterogeneity of this alloy. Samples taken from as-received state were heated with controlled ramp rates (1, 5, 10 and 20 °C min-1). Immediately after melting they were cooled with the same controlled ramp rate with the help of the laboratory experimental system SETARAM SETSYS 18TM TG/DTA/TMA. Then the microanalysis of minority phases was conducted with use of X-ray spectroscopy and microstructure of the individual samples was documented by scanning electron microscopy. Chemical microheterogeneity was determined on the basis of measured concentration data of selected elements (Al, Ti, Cr, Co, Ni, Nb, Mo, Ta and W) in representative areas of the individual samples structure.

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23

Idczak, Rafał, Robert Konieczny, and Jan Chojcan. "Mean hyperfine fields at 57Fe in dilute iron-based alloys studied by Mössbauer spectroscopy." Nukleonika 60, no. 1 (March 1, 2015): 39–42. http://dx.doi.org/10.1515/nuka-2015-0010.

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Abstract The room temperature Mössbauer spectra of 57Fe were measured for numerous dilute iron-based alloys Fe1−xDx (D = Al, Co, Cr, Mn, Mo, Ni, Os, Pt, Re, Ru, Ta, Ti, V, W, Zn), annealed at 1270 K for 2 h before the measurements. The spectra were analyzed using the Hesse–Rübartsch method in order to determine the mean hyperfine magnetic field <B> at the 57Fe nuclei as a function of concentration x of the minority component of the alloy. As the binary alloys are one-faze solid solutions of an element D in iron, a linear relationship between <B> and x is observed. The result supports the suggestion that Mössbauer spectroscopy is a useful tool for the study of dissolution of different elements in iron.

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24

Huang, Xiao-Wen, Anne-Aurélie Sappin, Émilie Boutroy, Georges Beaudoin, and Sheida Makvandi. "Trace Element Composition of Igneous and Hydrothermal Magnetite from Porphyry Deposits: Relationship to Deposit Subtypes and Magmatic Affinity." Economic Geology 114, no. 5 (August 1, 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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MIYAZAKI, Shogo, Yoshinori MURATA, and Masahiko MORINAGA. "Evaluation of Partitioning Ratios of Re Atoms in Ni-Al-Re-X (X : Cr, Mo, W, Ti, Ta, Nb, Co)Quaternary Alloys." Tetsu-to-Hagane 80, no. 2 (1994): 166–71. http://dx.doi.org/10.2355/tetsutohagane1955.80.2_166.

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Das, Saurabh Mohan, Mahander Pratap Singh та Kamanio Chattopadhyay. "Effect of Cr addition on the evolution of protective alumina scales and the oxidation properties of a Ta stabilized γ'-strengthened Co-Ni-Al-Mo-Ta-Ti alloy". Corrosion Science 172 (серпень 2020): 108683. http://dx.doi.org/10.1016/j.corsci.2020.108683.

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Zhu, Lilong, Changdong Wei, Haiying Qi, Liang Jiang, Zhanpeng Jin, and Ji-Cheng Zhao. "Experimental investigation of phase equilibria in the Co-rich part of the Co-Al-X (X = W, Mo, Nb, Ni, Ta) ternary systems using diffusion multiples." Journal of Alloys and Compounds 691 (January 2017): 110–18. http://dx.doi.org/10.1016/j.jallcom.2016.08.210.

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Tassiou, S., and E. Vassiliades. "GEOCHEMICAL STUDY OF THE URBAN AND SUBURBAN AREA OF NAFPLION CITY, ARGOLIDHA PREFECTURE, HELLAS." Bulletin of the Geological Society of Greece 43, no. 3 (January 24, 2017): 1520. http://dx.doi.org/10.12681/bgsg.11326.

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Soil, as the primary receptor of anthropogenic urban contamination acts as a sink for a variety of toxic and other hazardous substances. It constitutes, therefore, an indicator of contamination and may be utilised geochemically to assess environmental quality of urban and suburban areas. In Nafplion, an urban and suburban area of 50 km2 , was investigated using for the first time in Hellas an integrated approach with all available geoscientific techniques to make an in-depth environmental impact assessment. One of these techniques was applied geochemistry, which mapped the geochemistry of surface soil (0-10 cm) with 144 samples, collected on a regular grid of 500 x 500 km. The following fifty determinands were measured on the soil samples: Ag, Al, As, B, Ba, Be, Bi, Ca, Cd, Ce, Co, Cr, Cu, Fe, Ga, Ge, Hg, K, La, Li, Mg, Mn, Mo, Na, Nb, Ni, P, Pb, Rb, Re, S, Sb, Sc, Se, Sn, Sr, Ta, Te, Th, Ti, Tl, U, V, W, Y, Zn, Zr, pH, electrical conductivity and grain-size distribution. The aim of the geochemical study was to distinguish, as far as possible, the origin of chemical elements, and (i) to classify them as geogenic or anthropogenic; (ii) to delineate contaminated areas, and (iii) to assess potential future impacts of human activities on soil. Interpretation of the resulting geochemical patterns has shown that those of Al, Fe, Be, Ce, Cr, Co, Ga, Ge, K, La, Li, Mg, Nb, Ni, Rb, Sc, Sr, Tl, V, Y, W and Zr are of geogenic origin, since they are directly related to parent rocks, whereas patterns of As, B, Ba, Bi, Ca, Cd, Cu, Mn, Mo, Na, P, Pb, S, Sb, Sn, Th, U and Zn are interpreted as being of dual origin, geogenic and anthropogenic. In this paper, the geochemical distribution of only five elements shall be described, i.e., Pb, Zn, Cu, Ni and Na. This case study was indeed very interesting, since for the interpretation of some patterns, even the military history of the area had to be unravelled.

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Rakoczy, Łukasz, Bogdan Rutkowski, Małgorzata Grudzień-Rakoczy, Rafał Cygan, Wiktoria Ratuszek та Anna Zielińska-Lipiec. "Analysis of γ′ Precipitates, Carbides and Nano-Borides in Heat-Treated Ni-Based Superalloy Using SEM, STEM-EDX, and HRSTEM". Materials 13, № 19 (8 жовтня 2020): 4452. http://dx.doi.org/10.3390/ma13194452.

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The microstructure of a René 108 Ni-based superalloy was systematically investigated by X-ray diffraction, light microscopy, energy-dispersive X-ray spectroscopy, and electron microscopy techniques. The material was investment cast in a vacuum and then solution treated (1200 °C-2h) and aged (900 °C-8h). The γ matrix is mainly strengthened by the ordered L12 γ′ phase, with the mean γ/γ′ misfit, δ, +0.6%. The typical dendritic microstructure with considerable microsegregation of the alloying elements is revealed. Dendritic regions consist of secondary and tertiary γ′ precipitates. At the interface of the matrix with secondary γ′ precipitates, nano M5B3 borides are present. In the interdendritic spaces additionally primary γ′ precipitates, MC and nano M23C6 carbides were detected. The γ′ precipitates are enriched in Al, Ta, Ti, and Hf, while channels of the matrix in Cr and Co. The highest summary concentration of γ′-formers occurs in coarse γ′ surrounding MC carbides. Borides M5B3 contain mostly W, Cr and Mo. All of MC carbides are enriched strongly in Hf and Ta, with the concentration relationship between these and other strong carbide formers depending on the precipitate’s morphology. The nano M23C6 carbides enriched in Cr have been formed as a consequence of phase transformation MC + γ → M23C6 + γ′ during the ageing treatment.

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Rakoczy, Łukasz, Ondrej Milkovič, Bogdan Rutkowski, Rafał Cygan, Małgorzata Grudzień-Rakoczy, František Kromka та Anna Zielińska-Lipiec. "Characterization of γ′ Precipitates in Cast Ni-Based Superalloy and Their Behaviour at High-Homologous Temperatures Studied by TEM and in Situ XRD". Materials 13, № 10 (22 травня 2020): 2397. http://dx.doi.org/10.3390/ma13102397.

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In situ X-ray diffraction and transmission electron microscopy has been used to investigate René 108 Ni-based superalloy after short-term annealing at high-homologous temperatures. Current work is focused on characterisation of γ′ precipitates, their volume fraction, evolution of the lattice parameter of γ and γ′ phases and misfit parameter of γ′ in the matrix. Material in the initial condition is characterised by a high-volume fraction (over 63%) of γ′ precipitates. Irregular distribution of alloying elements was observed. Matrix channels were strongly enriched in Cr, Co, W and Mo, whereas precipitates contain large amount of Al, Ti, Ta and Hf. Exposure to high-homologous temperatures in the range 1100–1250 °C led to the dissolution of the precipitates, which influenced the change of lattice parameter of both γ and γ′ phases. The lattice parameter of the matrix continuously grew during holding at high temperatures, which had a dominant influence on the more negative misfit coefficient.

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Ajtic, Jelena, Darko Sarvan, Branislava Mitrovic, Ana Cuculovic, Rodoljub Cuculovic, and Marina Frontasyeva. "Elemental composition of moss and lichen species in eastern Serbia." Nuclear Technology and Radiation Protection 33, no. 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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Ángel Amorós a, José, Sandra Bravo, Francisco Jesús García Navarro, Francisco Pérez-de-los-Reyes, Francisco Sánchez-Ormeño, Jesús Gracía-Pradas, Raimundo Jiménez Ballesta, and 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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Ishiwari, R., N. Shiomi-Tsuda, and N. Sakamoto. "Stopping powers of Be, Al, Ti, V, Fe, Co, Ni, Cu, Zn, Mo, Rh, Ag, Sn, Ta, Pt and Au For 6.5 MeV protons." Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms 31, no. 4 (June 1988): 503–17. http://dx.doi.org/10.1016/0168-583x(88)90448-x.

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Shiomi-Tsuda, N., N. Sakamoto, and R. Ishiwari. "Stopping powers of Be, Al, Ti, V, Fe, Co, Ni, Cu, Zn, Mo, Rh, Ag, Sn, Ta, Pt and Au for 13 MeV deuterons." Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms 93, no. 4 (September 1994): 391–98. http://dx.doi.org/10.1016/0168-583x(94)95624-3.

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Min, P. G., V. V. Sidorov, S. A. Budinovskiy, and V. E. Vadeyev. "Influence of sulfur on heat resistance of single crystals of heat-resistant nickel alloy of Ni–Al–Co–Re–Ta–Mo–W–Ru–Cr system." Inorganic Materials: Applied Research 8, no. 1 (January 2017): 90–93. http://dx.doi.org/10.1134/s2075113317010233.

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Liu, Feng, Zexin Wang, Zi Wang, Jing Zhong, Xiaoke Wu, Zijun Qin, Zihang Li, et al. "High-throughput determination of interdiffusivity matrices in Ni-Al-Ti-Cr-Co-Mo-Ta-W multicomponent superalloys and their application in optimization of creep resistance." Materials Today Communications 24 (September 2020): 101018. http://dx.doi.org/10.1016/j.mtcomm.2020.101018.

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Duliu, Octavian G., Carmen I. Cristache, Ana-Voica Bojar, Gheorghe Oaie, Otilia-Ana Culicov, Marina V. Frontasyeva, and Emil Constantinescu. "The Geochemistry of 1 ky Old Euxinic Sediments of the Western Black Sea." Geosciences 9, no. 11 (October 23, 2019): 455. http://dx.doi.org/10.3390/geosciences9110455.

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To get more data on the geochemistry of Black Sea euxinic sediments, a 50-cm core was collected at a depth of 600 m on a Western Black Sea Continental Platform slope. The core contained unconsolidated sediments rich in cocoolithic ooze and mud. Epithermal Neutron and Prompt Gamma Activation Analysis were used to determine the content of nine major (Na, Mg, Al, Si, K, Ca, Ti, Mn, and Fe as oxides) and 32 trace elements (Cl, Sc, V, Cr, Co, Ni, Zn, As, Se, Br, Rb, Sr, Zr, Mo, Sn, Sb, Cs, Ba, La, Ce, Nd, Sm, Eu, Gd, Tb, Dy, Yb, Hf, Ta, W, Th, and U) with a precision varying between 3 and 9%. The core contained unconsolidated sediment rich in coccolithic ooze and mud. Previous 210 Pb geochronology suggests an age of ∼1 ky of considered sediments. Major components distribution showed that, except for Cl and Ca, the contents of all other elements are similar to Upper Continental Crust (UCC) and North American Shale Composite (NASC). The distribution of the 32 trace elements showed similarities to the UCC, except for redox-sensitive metals Fe, Se, Mo, and U, of which the significantly higher content reflects the presence of euxinic conditions during deposition. A chondrite normalized plot of nine rare earth elements indicated a similarity to UCC and NASC, suggesting a continental origin of sedimentary material.

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Nomoto, Sukeharu, Masahito Segawa, and Makoto Watanabe. "Non- and Quasi-Equilibrium Multi-Phase Field Methods Coupled with CALPHAD Database for Rapid-Solidification Microstructural Evolution in Laser Powder Bed Additive Manufacturing Condition." Metals 11, no. 4 (April 13, 2021): 626. http://dx.doi.org/10.3390/met11040626.

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A solidification microstructure is formed under high cooling rates and temperature gradients in powder-based additive manufacturing. In this study, a non-equilibrium multi-phase field method (MPFM), based on a finite interface dissipation model, coupled with the Calculation of Phase Diagram (CALPHAD) database, was developed for a multicomponent Ni alloy. A quasi-equilibrium MPFM was also developed for comparison. Two-dimensional equiaxed microstructural evolution for the Ni (Bal.)-Al-Co-Cr-Mo-Ta-Ti-W-C alloy was performed at various cooling rates. The temperature-γ fraction profiles obtained under 105 K/s using non- and quasi-equilibrium MPFMs were in good agreement with each other. Over 106 K/s, the differences between the non- and quasi-equilibrium methods grew as the cooling rate increased. The non-equilibrium solidification was strengthened over a cooling rate of 106 K/s. Columnar-solidification microstructural evolution was performed at cooling rates of 5 × 105 K/s to 1 × 107 K/s at various temperature gradient values under a constant interface velocity (0.1 m/s). The results show that, as the cooling rate increased, the cell space decreased in both methods, and the non-equilibrium MPFM was verified by comparing with the quasi-equilibrium MPFM. Our results show that the non-equilibrium MPFM showed the ability to simulate the solidification microstructure in powder bed fusion additive manufacturing.

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Shvetsova, M. S., I. Z. Kamanina, M. V. Frontasyeva, A. I. Madadzada, I. I. Zinicovscaia, S. S. Pavlov, K. N. Vergel, and N. S. Yushin. "ACTIVE MOSS BIOMONITORING USING THE «MOSS BAG TECHNIQUE» AT THE STATE MUSEUM-RESERVE «TSARITSYNO»." Bulletin of Dubna International University for Nature, Society, and Man. Series: Natural and engineering sciences, no. 1 (42) (September 23, 2019): 68–75. http://dx.doi.org/10.37005/1818-0744-2019-1-68-75.

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Moscow is a large metropolis in which the air is affected by the constant effects of chemicals produced by industrial facilities, vehicles, residential heating and other human activities on a daily basis. The protected and park areas on the territory of Moscow have an important recreational role, therefore, air quality control in these territories should be carried out first. Active moss biomonitoring has been used as an alternative method to conventional atmospheric monitoring for more than 40 years. This type of biomonitoring is successfully applied all over the world: in China, Serbia, Moldova, Azerbaijan, Italy, Romania, etc. In this study, active moss biomonitoring was used for the first time on the territory of the Tsaritsyno Museum-Reserve to assess the air pollution. The moss species Sphagnum girgensohnii was chosen for the experiment. Neutron activation analysis was used to determine the concentrations of the elements: Na, Mg, Al, Cl, K, Ca, Sc, V, Cr, Mn, Fe, Co, Ni, Zn, Se, As, Br, Rb, Mo, Sr , Sb, Ba, Cs, La, Sm, Tb, Ce, Hf, Ta, W, Th, and U. The concentrations of Pb, Cu, and Cd were determined by atomic absorption spectrometry.

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Кропачева, Марья Юрьевна, Юлия Сергеевна Восель, Ксения Александровна Мезина, Дмитрий Константинович Белянин, Михаил Сергеевич Мельгунов та 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, № 9 (12 вересня 2022): 46–56. http://dx.doi.org/10.18799/24131830/2022/9/3683.

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Анотація:

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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Kłos, Andrzej, Yulia A. Aleksiayenak, Zbigniew Ziembik, Małgorzata Rajfur, Dominik Jerz, Maria Wacławek, and Marina V. Frontasyeva. "THE USE OF NEUTRON ACTIVATION ANALYSIS IN THE BIOMONITORING OF TRACE ELEMENT DEPOSITION IN THE OPOLE PROVINCE." Ecological Chemistry and Engineering S 20, no. 4 (December 1, 2013): 677–87. http://dx.doi.org/10.2478/eces-2013-0046.

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Abstract The neutron activation analysis procedure was used to determine the concentration of 42 elements: Na, Mg, Al, Cl, K, Ca, Sc, V, Cr, Mn, Fe, Ni, Co, Zn, As, Se, Br, Rb, Sr, Zr, Nb, Mo, I, Ag, Cd, Sb, Ba, Cs, La, Ce, Nd, Sm, Eu, Tb, Yb, Hf, Ta, W, Au, Hg, Th, and U accumulated in mosses sampled for testing in September and October 2011 in the Opole Province (Southern Poland). Samples of different moss species were collected near the intersections of the grid lines marked on the map of the province. The distance between the points was approximately 20 km. The analysis of the results made it possible to identify the places of increased deposition of element-pollutants and to indicate the potential sources of emission. Factor analysis revealed four components, two of which are of definite anthropogenic origin. The possible sources of elements are local industry and farming, and distant heavy industry complexes. The results have demonstrated the increased content of Cr, Cd, Hg, and U in moss samples collected in agricultural areas located in the southern part of the province. It has been concluded that the industrial areas of Rybnik and Ostrava and Karvina Coal Basin may be the potential source of emission of these elements.

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ABOLLINO, ORNELLA, MAURIZIO ACETO, SANDRO BUOSO, MASSIMO GASPARON, WILLIAM J. GREEN, MERY MALANDRINO, and EDOARDO MENTASTI. "Distribution of major, minor and trace elements in lake environments of Antarctica." Antarctic Science 16, no. 3 (September 2004): 277–91. http://dx.doi.org/10.1017/s0954102004002111.

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Анотація:

The concentrations of major, minor and trace metals were measured in water samples collected from five shallow Antarctic lakes (Carezza, Edmonson Point (No 14 and 15a), Inexpressible Island and Tarn Flat) found in Terra Nova Bay (northern Victoria Land, Antarctica) during the Italian Expeditions of 1993-2001. The total concentrations of a large suite of elements (Al, As, Ba, Ca, Cd, Ce, Co, Cr, Cs, Cu, Fe, Ga, Gd, K, La, Li, Mg, Mn, Mo, Na, Nd, Ni, Pb, Pr, Rb, Sc, Si, Sr, Ta, Ti, U, V, Y, W, Zn and Zr) were determined using spectroscopic techniques (ICP-AES, GF-AAS and ICP-MS). The results are similar to those obtained for the freshwater lakes of the Larsemann Hills, East Antarctica, and for the McMurdo Dry Valleys. Principal Component Analysis (PCA) and Cluster Analysis (CA) were performed to identify groups of samples with similar characteristics and to find correlations between the variables. The variability observed within the water samples is closely connected to the sea spray input; hence, it is primarily a consequence of geographical and meteorological factors, such as distance from the ocean and time of year. The trace element levels, in particular those of heavy metals, are very low, suggesting an origin from natural sources rather than from anthropogenic contamination.

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43

Zinicovscaia, Inga, Rodica Sturza, Octavian Duliu, Dmitrii Grozdov, Svetlana Gundorina, Aliona Ghendov-Mosanu, and Gheorghe Duca. "Major and Trace Elements in Moldavian Orchard Soil and Fruits: Assessment of Anthropogenic Contamination." International Journal of Environmental Research and Public Health 17, no. 19 (September 28, 2020): 7112. http://dx.doi.org/10.3390/ijerph17197112.

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The correct assessment of the presence of potentially contaminating elements in soil, as well as in fruits cultivated and harvested from the same places has major importance for both the environment and human health. To address this task, in the case of the Republic of Moldova where the fruit production has a significant contribution to the gross domestic product, the mass fractions of 37 elements (Na, Mg, Al, Ca, Si, K, Mn, Fe, Sc, Ti, V, Cr, Co, Ni, Zn, As, Br, Rb, Sr, Zr, Mo, Cd, Sb, Cs, Ba, La, Ce, Nd, Sm, Eu, Tb, Yb, Hf, Ta, W, Th, and U) were determined by instrumental neutron activation analysis in soil collected from four Moldavian orchards. In the case of three types of fruits, grapes, apples, and plums, all of them collected from the same places, only 22 elements (Na, Mg, Cl, K, Ca, Sc, Mn, Fe, Co, Ni, Cu, Zn, As, Br, Rb, Sr, Sb, Cs, Ba, La, Th, and U) were detected. The enrichment factor, contamination factor, geo-accumulation index, as well as pollution load index were calculated to assess the soil contamination. At the same time, the metal uptake from the soil into fruits was estimated by means of transfer factors. Soil samples showed for almost all elements mass fractions closer to the upper continental crust with the exception of a slightly increased content of As, Br, and Sb, but without overpassing the officially defined alarm thresholds. In the case of fruits, the hazard quotients for all elements with the exception of Sb in fruits collected in two orchards were below unity. A subsequent discriminant analysis allowed grouping all fruits according to their type and provenance.

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Zeng, Zhijie, Uzair Siddique, Miaojun Sun, Qin Gao, Yanting Chen, Lei Chen, and Zilong Li. "The Mineral Chemistry of Magnetite and Its Constraints on Ore-Forming Mechanism in the Sandaozhuang Skarn-Type W-Mo Deposit in East Qinling, China." Minerals 13, no. 8 (August 15, 2023): 1091. http://dx.doi.org/10.3390/min13081091.

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The Sandaozhuang super-large W-Mo deposit is located in the southern margin of the North China Craton, within the well-known East Qinling Mo mineralization belt, and is one of the typical skarn-type W-Mo deposits in China. Based on EMPA and LA-ICP-MS analyses, major and trace elements were presented, and the mineral chemistry of magnetite at various mineralization stages was discussed. Combining field observations, petrography, and geochemical characteristics, the magnetite at the Sandaozhuang deposit can be classified into three types, namely early-magmatic-stage high-temperature magnetite (Mag1), potassic-alteration-stage magnetite (Mag2), and retrograde-alteration-stage magnetite (Mag3). The Mag1 and Mag2 magnetites primarily occurred in granites in association with potassium (K) feldspar and biotite, whereas Mag3 is associated with metallic sulfide minerals that occurred mainly in vein-like structures in skarn. The three magnetites Mag1, Mag2, and Mag3 can be distinguished as having magmatic, magmatic–hydrothermal transition, and hydrothermal origins, respectively. All three types of magnetite exhibit a depletion of high-field-strength elements (HFSEs) such as Zr, Hf, Nb, Ta, and Ti, and large-ion lithophile elements (LILEs) including Rb, K, Ba, and Sr, compared to the mean continental crust composition. Conversely, they are enriched in elements such as Sn, Mo, V, Cr, Zn, and Ga. Mag3 showed no significant depletion of Co, Ni, Cu, and Bi, indicating that the influence of coexisting sulfides on the composition of magnetite at the Sandaozhuang deposit is limited. There are systematic variations in major and trace elements from Mag1 to Mag3, which exhibited similar patterns in trace element spider and rare earth element diagrams, and Y/Ho ratio, indicating a consistent source for the three types of magnetite. The changes in V and Cr contents and (Ti + V) vs. (Al + Mn) diagram of magnetite at the Sandaozhuang deposit reflected the evolution of ore-forming fluids with an initial increase in oxygen fugacity and a subsequent decrease, as well as a gradual decrease in temperature during skarn mineralization. The early high-temperature and high-oxygen-fugacity magmatic fluids became W and Mo enriched by hydrothermal fluid interaction. The rapid change in fluid properties during the retrograde alteration stage led to the precipitation of scheelite and molybdenite.

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45

Madadzada, Afag I., Shahla S. Nuhuyeva, Elshad A. Mammadov, Zakir A. Ibrahimov, Natig S. Jabbarov, Lyudmila P. Strelkova, and Marina V. Frontasyeva. "Heavy Metal Atmospheric Deposition Study in Azerbaijan Based on Moss Technique and Neutron Activation Analysis." Ecological Chemistry and Engineering S 29, no. 2 (June 1, 2022): 143–53. http://dx.doi.org/10.2478/eces-2022-0011.

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Abstract The results of this investigation show that Azerbaijan industries and agricultural sector provide considerable anthropogenic impact on the environment of Caucasus. The use of moss biomonitoring technique and neutron activation analysis (NAA) is a first attempt to study heavy metal atmospheric deposition in Azerbaijan, a country different relief and climate. The study was undertaken in the summer of 2015 of atmospheric deposition of man-made heavy metal pollutants in the area of mining and processing plant in Gadabay and Dashkasan mininig district. At the same time samples were collected from the Goygol State Reserve in the Lesser Caucasus not far from the city of Ganja. A total 85 moss samples (predominantly Pleurozium schreberi) collected in both environmentally contrast area. Elemental determination was carried out by epithermal neutron activation analysis (ENAA) at the reactor IBR-2 of Joint Institute for Nuclear Research (FLNP JINR). For the first time 44 elemental concentrations were determined (Na, Mg, Al, Si, Cl, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Br, Rb, Sr, Mo, Ag, Cd, In, Sb, I, Cs, Ba, La, Ce, Nd, Sm, Eu, Tb, Tm, Yb, Hf, Ta, W, Au, Th, U). Multivariate statistical analysis of the analytical results obtained will make it possible to identify the main sources of pollution and to assess the role of long-range transport of pollutants.

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46

Zeyle, Lyubov' Andreyevna, Ivan Viktorovich Novikov, Elena Vasilievna Petrova, and Evgenia Sergeevna Rabcevich. "ELEMENTAL COMPOSITION OF CHAGA MUSHROOM (INONOTUS OBLIQUUS)." chemistry of plant raw material, no. 1 (March 10, 2022): 251–60. http://dx.doi.org/10.14258/jcprm.2022019738.

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Birch chaga Inonotus obliquus is used as a component of many medicines. This is due to the versatile therapeutic effect associated with the content of a large number of biologically active substances of inorganic, organometallic and organic nature, a high content of macro- and microelements both in a free state and in the form of chelate complexes. To establish the qualitative and quantitative elemental composition of birch chaga, highly sensitive physicochemical methods of analysis were used, such as atomic emission spectroscopy (AES), inductively coupled plasma mass spectrometry (ICP-MS), and neutron activation analysis (NAA). The scientific novelty of this study lies in the conduct of a complex physicochemical elemental layer-by-layer analysis of chaga, the analogs of which have not been found in the available literature. The analyzed samples of birch chaga layers contain the following elements: K, Na, Mg, Ca, Zn, Mn, Cu, Fe, Mo, Co, Cr, P, Br, Se, V, Al, Ba, Li, Ag, Au, Rb, Cs, As, Sb, B, Sr, Pb, Ni, Ti, Be, Ta, U, Th, Sc; the concentration of elements is highest in the outer layer of the fungus. It is noted that the content of both biogenic elements (K, Co, Mn) and potentially toxic (Ag, Br, Rb) is significantly higher than the corresponding clarkes in bios. Differences in the content of elements correlate with modern biochemical concepts of the composition of chaga, and in most cases also correlate with the values of clarkes in bios. The value of the detected toxicant elements does not exceed the MPC.

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47

Zeyle, Lyubov' Andreyevna, Ivan Viktorovich Novikov, Elena Vasilievna Petrova, and Evgenia Sergeevna Rabcevich. "ELEMENTAL COMPOSITION OF CHAGA MUSHROOM (INONOTUS OBLIQUUS)." chemistry of plant raw material, no. 1 (March 10, 2022): 251–60. http://dx.doi.org/10.14258/jcprm.2022019738.

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Анотація:

Birch chaga Inonotus obliquus is used as a component of many medicines. This is due to the versatile therapeutic effect associated with the content of a large number of biologically active substances of inorganic, organometallic and organic nature, a high content of macro- and microelements both in a free state and in the form of chelate complexes. To establish the qualitative and quantitative elemental composition of birch chaga, highly sensitive physicochemical methods of analysis were used, such as atomic emission spectroscopy (AES), inductively coupled plasma mass spectrometry (ICP-MS), and neutron activation analysis (NAA). The scientific novelty of this study lies in the conduct of a complex physicochemical elemental layer-by-layer analysis of chaga, the analogs of which have not been found in the available literature. The analyzed samples of birch chaga layers contain the following elements: K, Na, Mg, Ca, Zn, Mn, Cu, Fe, Mo, Co, Cr, P, Br, Se, V, Al, Ba, Li, Ag, Au, Rb, Cs, As, Sb, B, Sr, Pb, Ni, Ti, Be, Ta, U, Th, Sc; the concentration of elements is highest in the outer layer of the fungus. It is noted that the content of both biogenic elements (K, Co, Mn) and potentially toxic (Ag, Br, Rb) is significantly higher than the corresponding clarkes in bios. Differences in the content of elements correlate with modern biochemical concepts of the composition of chaga, and in most cases also correlate with the values of clarkes in bios. The value of the detected toxicant elements does not exceed the MPC.

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48

Cao, Jiaxu, Yingkun Liu, Chunming Deng, Kun Yang, and Feng Li. "Interdiffusion Behaviour of NiCoCrAlY Coating and N5 Single Crystal Superalloy." Coatings 10, no. 4 (April 16, 2020): 393. http://dx.doi.org/10.3390/coatings10040393.

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This paper aims at investigating the microstructure and phases evolution of single crystal superalloy/high temperature protective coating during high temperature static oxidation, and exploring the influence of element interdiffusion behaviour on microstructure and phase evolution of the single crystal superalloy substrate. A NiCoCrAlY high-temperature protective coating was deposited on the Ni-based single-crystal superalloy by low-pressure plasma spraying technology. The coated samples were subjected to static oxidation for 200 h at a constant temperature of 1100 °C. Scanning electron microscope, energy dispersive spectrometer and X-ray diffraction were used to characterise the microstructure and phase after interdiffusion between the coating and the substrate at high temperature. The results showed that a dense thermally grown oxide layer was formed on the surface of the NiCoCrAlY coating after oxidation for over 100 h. The only interdiffusion zone was formed after oxidation for 50 h, while both interdiffusion zone and secondary reaction zone could be observed after oxidation for over 100 h. The thickness of interdiffusion zone and secondary reaction zone is increased with the extension of oxidation time, and the grain growth of topological close-packed phase in the secondary reaction zone is found. Al, Cr and Co in the coating diffuse from the coating to the substrate, while Ni and refractory materials like Ta, Mo, Re and W diffuse from the coating to the substrate. The interdiffusion of coating and substrate leads to the instability of γ/γ′ phase in the substrate, which finally results in the formation of W, Re and Cr-rich needle-like topological close-packed phase in the substrate.

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49

Dunaev, Anatoly M., Igor V. Rumyantsev, Irina B. Agapova, Vladimir I. Grinevich, Konstantin N. Vergel, and Svetlana F. Gundorina. "PHYSICAL AND CHEMICAL AND BIOLOGICAL MONITORING IN CENTRAL RUSSIA: INVESTIGATION OF QUALITY OF ATMOSPHERIC AIR AND SOIL IN TERRITORY OF RODNIKI CITY." IZVESTIYA VYSSHIKH UCHEBNYKH ZAVEDENIY KHIMIYA KHIMICHESKAYA TEKHNOLOGIYA 61, no. 8 (August 21, 2018): 96. http://dx.doi.org/10.6060/ivkkt20186108.5721.

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Air and soil quality assessment at the Rodniki town, Ivanovo Region, was performed using physical chemical analysis and biomonitoring techniques: soil and snow analysis, moss biomonitoring, fluctuating asymmetry (IFA) for the silver birch (Betula pendula Roth.). Elemental content in moss, soil and snow samples was determined by neutron activation analysis (NAA) and atomic absorption spectrometry (AAS). A total of 40 elements (Na, Mg, Al, Cl, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Zn, As, Se, Br, Rb, Sr, Zr, Mo, Ag, In, Sb, I, Cs, Ba, La, Ce, Nd, Sm, Eu, Gd, Tb, Tm, Yb, Lu, Hf, Ta, W) was determined by NAA. To determine concentrations of Pb, Cd, and Cu AAS technique was used. To reveal potential sources of element-pollutants the descriptive statistics and factor analysis were applied in OriginPro 8 and SPSS 17.0 software packages for Windows. To evaluate the contribution to the metal content in moss from anthropogenic sources, enrichment factors (EF) were calculated. Distribution maps were prepared to point out areas most affected by pollution and to characterize the main deposition patterns of pollutants. To create GIS maps QGIS software was used. The complex assessment of the air and soil quality of the Rodniki town and its vicinity showed an acceptable level of the contamination. It was established that the main source of pollution is the machine-building plant situated in the north of the town. This plant causes soil contamination by Zn, As, Fe, and Co. The IFA values successfully confirm the obtained concentration data. Besides, it was established that the soil contamination has a bigger influence on IFA than atmospheric pollution. Measures for nature conservation are suggested.

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50

Morakabati, Maryam, mohammad javad karimian, and hassan badri. "Evaluation of the thermomechanical behavior of the new generation nickel-cobalt Co-Ni-Al-Cr-W-Ti-Ta-Nb-Mo-C-B (%wt) superalloy Using constitutive equations and deformation processing maps." Modares Mechanical Engineering 23, no. 3 (March 1, 2023): 191–97. http://dx.doi.org/10.52547/mme.23.3.191.

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