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Zirconate pyrochlores have been extensively studied as candidate waste forms for the immobilization of actinide wastes due to their flexible crystal chemistry, excellent structural stability, and exceptional radiation tolerance. Herein, we report the synthesis of a series of compounds Eu2Zr2–xO7–2x (x = 0–1, step = 0.125) using a co‐precipitation route to form solid solutions between the two end members, Eu2Zr2O7 pyrochlore and Eu2ZrO5 defect fluorite. It is important to understand the pyrochlore to defect fluorite transformation as a function of Zr/Ln molar ratio. The structural investigation by x‐ray diffraction has shown the increasing cation disorder and corresponding structural transitions from the ordered pyrochlore to disordered pyrochlore, then to defect fluorite. While diffuse reflectance spectroscopy provides similar optical absorption features reflecting the presence of Eu(III) ion, Raman spectroscopy has revealed more details on the phase transition and short‐range structures. This work highlights the structural flexibility in zirconate materials as potential nuclear waste forms for the immobilization of actinide‐rich waste streams, especially suitable for the separated minor actinides. [ABSTRACT FROM AUTHOR]

Using mechanical activation of an oxide mixture containing 0.2 wt% hexagonal boron nitride, followed by high-temperature firing (1400–1500 °C), we prepared single-phase (La 0.2 Nd 0.2 Ho 0.2 Lu 0.2 Y 0.2) 2 ZrO 5 ceramic, a high-entropy oxide (HEO) analog of Gd 2 ZrO 5 , whereas we failed to obtain single-phase Gd 2 ZrO 5 under similar conditions: the material consisted of two phases, with the fluorite and bixbyite structures, like in the case of conventional synthesis or coprecipitation in previous work. Thus, the use of the HEOs allowed us to obtain a phase-pure compound with the fluorite structure at a markedly lower synthesis temperature. An important role was played by 0.2 wt% hyperstoichiometric hexagonal BN additions, which ensured considerable amorphization of the starting oxides. The start powders and resulting ceramics were studied by X-ray diffraction, SEM analyses and conductivity was measured by impedance spectroscopy method in dry and wet air. The highest proton conductivity, ∼2.5 × 10−5 S/cm at 630 °C, was offered by the (La 0.2 Nd 0.2 Ho 0.2 Lu 0.2 Y 0.2) 2 ZrO 5 HEO ceramic. The use of HEO analogs of various compounds can be helpful for not only assessing thermodynamic properties of ceramics (reduction in synthesis and polymorphic transformation temperatures), but also preparing proton conductors when it is necessary to enhance hydrating properties of the cation sublattice. [ABSTRACT FROM AUTHOR]

Phase formation in the BaF2–NdF3 and BaF2–PrF3 systems was studied by solid‐phase annealing at 750°С and syntheses in molten NaNO3 flux at 500°С. We observed the formation of Ba1−хRхF2+х fluorite solid solutions in the aforementioned systems, and these solid solutions underwent ordering to form ordered Ba4Nd3F17 and Ba4Pr3F17 fluorite‐like phases at 917°С and 880°С, respectively. [ABSTRACT FROM AUTHOR]

The formation of the solid phases CaS, 3CaO.SiO2 and CaO.Al2O3 around the lime particle decreases the efficiency of desulfurization by the kanbara reactor (KR) process. The addition of fluxes reduces the formation of these phases. The addition of Al and Si can also have this effect, depending on the added levels. In this study, different mixtures based on CaO with different levels of fluorspar, sodalite (Nepheline Syenite), and SiO2 and Al2O3 content were studied and used in the desulfurization process of hot metal. These mixtures were added to a bath of liquid hot metal at 1400 °C. All experiments were performed with mechanical agitation. Samples were taken at times of 5, 10, 15, and 20 min, and analyses were performed to evaluate the variation of sulfur over time. The Thermo‐Calc software was used to determine the formed phases, solid fraction, and liquid fraction of the different mixtures. With this data, different values of the Global Desulfurization Factor (FGDeS) were calculated, which was developed to evaluate and predict the efficiency of hot metal desulfurizing mixtures by the KR process. The results of showed that fluorspar was more efficient than sodalite. The FGDeS had a correlation factor (R2) above 0.9 with the desulfurization efficiency. [ABSTRACT FROM AUTHOR]

A new series of 20-component fluorite-based compositionally complex oxides (20CCFBO x Nb/Ta) with the general chemical formula (15RE 1/15) 2 x +1 (Ce 1/3 Zr 1/3 Hf 1/3) 3–3 x (Nb 1/2 Ta 1/2) x O 8- δ (0 ≤ x ≤ 1, where 15RE 1/15 = La 1/15 Pr 1/15 Nd 1/15 Sm 1/15 Eu 1/15 Gd 1/15 Tb 1/15 Dy 1/15 Y 1/15 Ho 1/15 Er 1/15 Tm 1/15 Yb 1/15 Lu 1/15 Sc 1/15) are synthesized. Despite that the Gibbs phase rule allows for the existence of up to 20 phases at the thermodynamic equilibrium, 17 of the 20CCFBO x Nb/Ta compositions synthesized in this study all possess single ultrahigh-entropy phases in fluorite, pyrochlore, or weberite structure, as shown by X-ray diffraction (XRD). Only < 1 vol% of secondary phases are observed in two compositions near the phase-transition points. With changing compositional variable x , this series of 20CCFBO x Nb/Ta undergoes an abrupt fluorite-pyrochlore transition at x = ∼0.27 and an abrupt pyrochlore-weberite transition at x = ∼0.87. Careful characterization reveals abrupt changes of order parameters at both phase transitions. In addition, weberite short-range ordering can persist into the long-range pyrochlore phase, which leads to the lowest thermal conductivities. [ABSTRACT FROM AUTHOR]

Solid solutions of rare earth titanates with high contents of rare earth oxides of up to 50-62% have been synthesized by the co-precipitation method and their structure, microstructure and conductivity in dry and wet air have been studied. Proton conductors have been found for the first time in solid solutions of rare earth titanates with a high content of Ln2O3 (>50%) with a nominal formula composition of (LnxTi1-x)4O8-2x (Ln = Yb, Er, Ho, 0.667 = x = 0.765). Among (LnxTi1-x)4O8-2x (Ln = Yb, Er, Ho, x = 0.684), (HoxTi1-x)4O8-2x (x = 0.684) showed the maximum conductivity in wet air. In this context, four additional compositions (HoxTi1-x)4O8-2x (x = 0.718, 0.734, 0.75, and 0.765) were synthesized in the holmium series. An increase in the holmium content leads to an increase in the proton transfer coefficients; at the same time, a more complex nature of the dependence of the conductivity under dry and wet atmospheres is observed. For the fluorite-like solid solution (HoxTi1-x)4O8-2x (0.701 = x = 0.765), the proton transfer coefficients were found to be ~0.9 in the range of 200-450 °C. As the temperature continues to rise, the proton conductivity decreases quite sharply and the transfer coefficient becomes as low as 0.3 at 700 °C. The increase in proton conductivity in the Yb-Er-Ho series is associated with an increase in the hydrophilic properties of rare earth cations. In the (HoxTi1-x)4O8-2x (x = 0.667 = x = 0.765) series, the conductivity in wet air was ~1 × 10-6 S cm-1 at 450 °C for most compositions. The conductivity of ceramics with x = 0.701 and 0.75 is about 2 times higher, which may be due to the optimal size of pyrochlore nanodomains in the fluorite matrix for x = 0.701 and the formation of pure fluorite for x = 0.75, respectively. [ABSTRACT FROM AUTHOR]

Ceria-based electrolyte materials are of great interest for solid oxide fuel cell applications because they exhibit low ohmic resistance and high ionic conductivity, especially at a low temperature of 550oC. Consequently, we have designed a very interesting electrolyte Al and Nd dual-doped SDC (Sm 0.1 Ce 0.9 O 2) using the sol–gel technique to function as an electrolyte for LT–CFCs (low-temperature ceramic fuel cells). The AN–SDC (Al 0.15 N 0.15 -Sm 0.1 Ce 0.6 O 2) as an electrolyte shows a maximum power output of 1085 mW/cm2 with a high ionic conductivity of 0.22 S/cm at 550oC. This high performance is mainly because of the co-doping into SDC, which facilitates many oxygen vacancies, enabling faster stabilized ion transportation through the AN–SDC lattice. The low resistance of either the ohmic and grain boundary resistance + the microstructure features of AN–SDC contribute to achieving higher fuel cell performance. In addition, dual doping into SDC might build a synergistic effect, which further improves devices' performance. The ionic conduction mechanism has been explained based on the dual doping of the incorporation of Al and Nd into the SDC. Dual doping is a promising, feasible avenue for designing electrolytes to enhance the performance of LT–CFC devices. [Display omitted] [ABSTRACT FROM AUTHOR]

Direct Ink Writing has been demonstrated to be a promising route to produce ceramic catalysts with complex geometries and enhanced catalytic performances. To increase the catalytic performances, chemical etching can be conducted to get an interconnected and hierarchical porous structure, to increase the surface area and the contact time of the reactants. In this work, DIW alpha (α)-Al 2 O 3 catalysts were chemically etched with hydrofluoric acid (HF). Several combinations of acid concentrations and etching times were studied to find the optimal etching condition. For HF concentration of 5, 20 and 40 wt%, the optimal etching time was 48, 24 and 5 h, respectively, being 40 wt% the concentration that shows the greatest increase of surface porosity (of around 5%). HF etching can produce an interconnected porosity on 3DP α-Al 2 O 3 , but it does not yield improvement in catalytic performances when the content of fluor (F) is higher than 10 at% since it produces parasite reactions. [ABSTRACT FROM AUTHOR]

The Al/Sm 2 Ce 2 O 7 /ITO (Al/SCO/ITO) structure resistive random access memory (RRAM) was prepared using RF magnetron sputtering, and its resistive switching (RS) behaviors were systematically investigated. The memory exhibited a high switching cycle of 1031, along with set/reset voltages of −1.55/0.53 V and a R on /R off ratio exceeding 102. This high performance can be attributed to the presence of intrinsic oxygen vacancies in the defective fluorite structure, accounting for 34.44 % of the vacancies. This vacancy percentage can be increased to 41.97 % by simultaneously transforming Ce4+ to Ce3+ ions through annealing treatment, thereby releasing additional oxygen vacancies. Despite this increase, there remains a sufficient window (R on /R off > 10) to distinguish between the high-resistance state (HRS) and low-resistance state (LRS) of the SCO device. Furthermore, the device, when subjected to post-metal annealing (PMA), exhibits a high endurance of up to 1815 cycles, a set/reset voltages of −2.19/1.31 V, a R on /R off ratio of >10, and a retention time of over 104 s at 25 °C and 85 °C. However, it is important to note that PMA-treated device requires a higher forming voltage due to the formation of a thicker AlO x layer. This study highlights the potential of Al/SCO/ITO memory devices for RRAM applications. [ABSTRACT FROM AUTHOR]

The surface properties of bastnaesite and parisite are similar to their associated gangue mineral, fluorite, which makes the flotation separation of these two rare earth minerals from fluorite one of the industry's most significant challenges. This study systematically investigates the inhibitory effects and mechanisms of sodium silicate (SS) on bastnaesite, parisite, and fluorite in an octyl hydroxamic acid (OHA) collector system through flotation experiments, various modern analytical methods, and DFT simulations. The flotation test results indicate that the inhibition effects of SS on the three minerals are in the order: fluorite > parisite > bastnaesite. Detection and analysis results indicate that SS forms hydrophilic complexes with Ca atoms on the surfaces of fluorite and parisite, enhancing surface hydrophilicity and inhibiting OHA adsorption, but its impact on bastnaesite is relatively minor. DFT simulation results show that OHA forms covalent bonds with metal ions on mineral surfaces, favoring five-membered hydroxamic-(O-O)-Ce/Ca complexes, and reacts more strongly with Ce atoms than Ca atoms. SS primarily forms covalent bonds with metal atoms on mineral surfaces via the SiO(OH)3− component, and OHA and SS compete for adsorption on the mineral surfaces. OHA has a stronger affinity for bastnaesite, whereas SS shows the highest affinity for fluorite, followed by parisite, and the weakest affinity for bastnaesite. [ABSTRACT FROM AUTHOR]

The floatability of fluorite and calcite exhibit similar properties, rendering their flotation separation challenging. Macromolecular polysaccharide reagents containing the polyhydroxyl group have shown broad promising application. The selectivity of polysaccharide is relatively low. In this study, the introduction of Fe3+ was employed to enhance the selective adsorption capacity of Pullulan polysaccharide towards fluorite and calcite minerals, thereby achieving effective flotation separation. Furthermore, the mechanism underlying intramolecular interactions was elucidated. The DFT calculation and XPS analysis revealed that the adsorption of Fe3+ on the calcite surface was more favorable, leading to the formation of a Ca-O-Fe structure. The MD simulation, XPS analysis, and Zeta potential analysis revealed that the Fe-OH groups on the surface of calcite reacted with the -OH groups in Pullulan and formed bonds, resulting in the formation of a Calcite-Fe-Pullulan structure. This facilitated the attachment of a significant number of Pullulan molecules to the calcite surface. The formation of a hydrophilic layer on the outer surface of calcite by Pullulan, in contrast to the absence of such layer on fluorite's surface, results in an increased disparity in surface floatability between these two minerals, thereby enhancing the efficiency of flotation separation. [ABSTRACT FROM AUTHOR]

Super-resolution single-molecule localization microscopy (SMLM) of presynaptic active zones (AZs) and postsynaptic densities contributed to the observation of protein nanoclusters that are involved in defining functional characteristics and in plasticity of synaptic connections. Among SMLM techniques, direct stochastic optical reconstruction microscopy (dSTORM) depends on organic fluorophores that exert high brightness and reliable photoswitching. While multicolor imaging is highly desirable, the requirements necessary for high-quality dSTORM make it challenging to identify combinations of equally performing, spectrally separated dyes. Red-excited carbocyanine dyes, e.g., Alexa Fluor 647 (AF647) or Cy5, are currently regarded as "gold standard" fluorophores for dSTORM imaging. However, a recent study introduced a set of chemically modified rhodamine dyes, including CF583R, that promise to display similar performance in dSTORM. In this study, we defined CF583R's performance compared to AF647 and CF568 based on a nanoscopic analysis of Bruchpilot (Brp), a nanotopologically well-characterized scaffold protein at Drosophila melanogaster AZs. We demonstrate equal suitability of AF647, CF568 and CF583R for basal AZ morphometry, while in Brp subcluster analysis CF583R outperforms CF568 and is on par with AF647. Thus, the AF647/CF583R combination will be useful in future dSTORM-based analyses of AZs and other subcellularly located marker molecules and their role in physiological and pathophysiological contexts. [ABSTRACT FROM AUTHOR]

Purpose: In this paper, the effects of different activation methods on the reactivity and hydration properties of fluorite tailings were studied for the purpose of resource utilization of fluorite tailings. Method; In this paper,three methods of heat treatment, mechanical grinding and combined excitation were used to stimulate the activity of fluorite tailings,and it was used as an admixture to prepare cement paste,and its reactivity and hydration properties were evaluated. Result: After mechanical excitation and alkali-thermal excitation, fluorite tailings can exhibit certain reactivity, and significant amorphous glass phase can be observed. The strength of cement paste prepared with fluorite tailings as admixture increased by more than 20%. Conclusion: Mechanical excitation increases the specific surface area and decreases the particle size, which is conducive to the participation of fluorite tailings in hydration reaction,produces the micro-aggregate effect,plays a filling role,and improves the compressive strength of cement paste mixed with fluorite tailings. The alkali-heat-activated fluorite tailings are hydraulically [ABSTRACT FROM AUTHOR]

This is an article in the field of mineral processing engineering. The beryllium ore in Hunan Province contains 0.47% BeO and 44.86% CaF2. The beryllium ore is chrysoberyl. The main gangue minerals are chlorite, mica, calcite, dolomite, etc. The disseminated particle size of beryllium ores is relatively fine, closely associated with chlorite, calcite, etc. So it is difficult to beneficiate. The beneficiation process flow is adopted by flotation of the sulphide ore first, then preferential flotation of fluorite, and the last reverse flotation of gangue minerals after flotation tailings deslimed. At the condition of the grinding fineness -0.074 mm accounted for 80%, the combined collectors of butylxanthate + ammonium dibutyldithiophosphate + sodium diethyldithiocarbamate for flotation were used to remove sulfide ores. Then fluorite concentrate with CaF2 grade of 96.32% and recovery rate of 70.34% were obtained by flotation of fluorite with the combined collectors oxidized paraffinum sodium salt + sodium oleate. After the flotation tailings are deslimed, reverse flotation of gangue minerals is adopted and the beryllium concentrate with BeO grade of 1.57% and recovery rate of 67.95% is obtained. The subsequent beryllium concentrate can be extracted by metallurgical method to obtain beryllium oxide products. This process realizes the multipurpose recovery of beryllium ores of chrysoberyl type and fluorite ores, and provides a reference for the development and utilization of the same type of beryllium ores.

Studies conducted in NaF-containing hydrothermal fluids have shown that the oxide compounds Sb5+ are unstable at 800 °C, Рtotal = 200 MPa and fO2 (fH2) specified by Co–CoO and Ni–NiO buffers interact with the Pt material of the ampoule, forming antimony intermetallics with platinum on the inner surface of the ampoule. The formation of the following intermetallics was established through the analysis of data obtained from studies conducted on an electronic microscope: Pt90.3±0.8Sb9.7 (~ Pt10Sb), Pt82.8±1.3Sb17.2 (~ Pt5Sb) and Pt69.2±4.4Sb30.8. Pt10Sb compound which was obtained on the inner surface of the Pt ampoule is the limiting solid solution of antimony in platinum at 800 °C. It exhibits a cubic crystal system with a lattice constant of a = 3.943(3) Å and forms an underdeveloped surface < 111>. Pt5Sb compound, presumably hexagonal P6/mmm crystal system with unit cell parameters a = b = 4.56(4), c = 4.229(2) Å, α = β = 90°, γ = 120°, forms a thin film (≤ 10 μm) on the Pt surface and appears to be a metastable phase. The intermetallic compound of Pt69Sb31 is a rapidly cooled melt of appropriate composition. A mechanism for deep penetration of Sb into the walls of the Pt ampoule is proposed. [ABSTRACT FROM AUTHOR]

This is an article in the field of mining processing engineering. This article takes Dechang Daluchao rare earth mineral processing tailings as the research object, conducts a beneficiation test study on fluorspar recovery, and determines the beneficiation process flow and reagent of "flotation desulphurization - mixed flotation - flotation separation of fluorite, strontium and barium" for fluorite recovery. In the flotation test, the new MQY collector and DC-2 high-efficiency inhibitor were used to efficiently capture fluorite while achieving precise separation of fluorite and gangue minerals. In the final full-process test, a fluorspar concentrate with a CaF2 grade of 94.39% and a recovery rate of 51.41% was obtained. The test indicators were relatively ideal. This article tested and verified the feasibility of recovering fluorspar from the Dalunchao rare earth tailings. The final beneficiation process is reasonable and has good test indicators. It can be used as a technical basis for the utilization and recovery of fluorspar resources in the Dalunchao rare earth tailings.

The new generation of T/EBCs requires their top layer materials with good resistance to severe corrosion by CMAS. Rare-earth zirconates/hafnates with pyrochlore structure are regarded as promising candidates for T/EBC. In this work, the corrosion behaviours and mechanisms of plasma-sprayed Gd 2 M 2 O 7 (M = Zr, Hf) coatings at 1300 and 1500 °C for 4–25 h were investigated. The Gd 2 M 2 O 7 coating showed good corrosion resistance under long-term corrosion at 1300 °C. The Gd 2 M 2 O 7 coatings reacted with CMAS and precipitated apatite and fluorite, forming a dense layer that can prevent further penetration of CMAS. However, the CMAS penetrated into the Gd 2 M 2 O 7 coatings because of the sharply decreased viscosity of the CMAS as the temperature raised to 1500°C, forming another infiltration layer. The results also suggested that the Gd 2 Hf 2 O 7 possessed better resistance to CMAS corrosion than Gd 2 Zr 2 O 7. [ABSTRACT FROM AUTHOR]

Fluorite, as a vital calcium-containing mineral, usually coexists with calcite. When using the traditional collector sodium oleate (NaOL), froth flotation could not separate fluorite and calcite well on account of their similar surface properties. Meanwhile, a large amount of sodium silicate (SS) needs to be added to depress calcite, resulting in difficulties in tailings settlement and wastewater treatment. Therefore, a nontoxic and inexpensive surfactant saponified tricarboxylic acid (TA) was developed as a new collector. The flotation test results showed that TA had a higher selectivity for fluorite than NaOL, leading to the selective separation of both minerals. Zeta potential measurements indicated that TA was negatively charged and was strongly adsorbed on fluorite due to electrostatic interactions at pH 9.0. FTIR, XPS, DFT, and crystal chemistry calculations revealed TA had a stronger chemical interaction with fluorite due to its higher surface Ca activity and density, forming a TA-Ca complex through the bidentate coordination. In contrast, the interaction of TA with calcite could be ignored. In addition, the results of the surface tension and dynamic foam stability tests revealed that TA possessed the excellent foam performance. Therefore, these properties give TA excessive potential for industrial application and environmental protection in fluorite flotation. Density and activity of Ca atoms on fluorite are higher than those on calcite. TA could selectively separate fluorite from calcite without any depressants. TA had a stronger chemical interaction with fluorite to form the Ca – TA complex. TA possesses excellent foam properties and suitable hydrophobicity. [ABSTRACT FROM AUTHOR]

The Tianshanbeilu cemetery is the largest Bronze Age cemetery in eastern Xinjiang, China, and plays important roles in connecting the Eurasian interior to the Hexi Corridor, and further to the Central Plains region. Utilizing micro-XRF and Raman spectroscopy techniques, we identified a fluorite bead at this cemetery. This barrel bead is the earliest record of such a fluorite bead in China, dating back to approximately 1385–1256 BCE. Comparing the unearthed records of fluorite beads in eastern China spanning from the Neolithic Age to the Western Zhou dynasty, we notice that in the early Western Zhou period, fluorite beads found in élite burials are only in barrel or biconical shapes, both of which first appeared in the eastern region of Xinjiang, such as the Tianshanbeilu cemetery in Hami and the Yanghai cemetery in the Turpan Basin. We proposed that the barrel fluorite bead drilled by metal tubular drill first appearing in the Tianshanbeilu cemetery might have spread eastward to the Central Plains region and finally constituted a component of the ritual revolutions during the Western Zhou dynasty. [ABSTRACT FROM AUTHOR]

A multi-crystalline specimen of gadolinium zirconate (Gd 2 Zr 2 O 7) has been synthesized by solid-state reaction method (un-milled sample). The sample underwent high-energy ball-milling for 6 h, 12 h, 18 h, and 24 h durations (milled samples). An investigation has been conducted to examine the effects of mechanical attrition on structural, microstructural, vibrational, and dielectric properties. Notably, the elemental analysis of the samples reveals a substantial increase in the atomic percentage of oxygen. This indicates the partial development of an oxygen-enriched phase during the milling process. The Rietveld refinement of X-ray diffraction profiles indicates that all the samples have a disordered fluorite structure however, in the 18 h and 24 h milling samples in addition to this main phase, a minor ordered phrochlore-phase has been formed. The nano-phasic character of all the milled samples has been confirmed by the SEM, TEM, and BET surface area analysis. The BET isotherms displayed a type –II hysteresis loop, indicating that all the samples are macro-porous with a pore diameter exceeding 50 nm. The FTIR and Raman spectrum studies indicate the presence of both defect fluorite and pyrochlore phases in the samples. An in-depth investigation has been conducted on the impact of mechanical milling-induced reduction in particle size and micro-strain on conduction mechanism, dielectric relaxation, and variation of various dielectric properties with frequency. [ABSTRACT FROM AUTHOR]

Purpose: In response to the problems of low mechanization, low production efficiency, large number of workers, difficult production management, and high safety risks in the ordinary upward horizontal layered tailings cemented filling mining method used in a domestic fluorite mine, combined with the mining technology conditions of the ore body, the mining method is optimized. Method: Through the study of the structural parameters of the mining site, mining preparation and cutting engineering, and the mining process, an automated and intelligent upward horizontal layered tailings cemented filling mining method was ultimately determined. Intelligent mining equipment was used to replace manual mining operations, achieving few or even no personnel. Result: Production practice shows that this method is safe and reliable, and 5G remote control operation is achieved in the drilling, pilling, shoveling, and filling processes. Automatic positioning and autonomous rock drilling operations are achieved under appropriate control height conditions, and the number of workers can be reduced by more than 50%, achieving good economic and social benefits. Conclusion: With the gradual entry of mineral resources into deep mining in China, mining will face harsh and high-risk working environments such as high ground pressure and high rock bursts. The intelligent upward horizontal layered filling method proposed in this article has good reference significance and wide promotion and application value for deep and difficult to mine ore body mining. [ABSTRACT FROM AUTHOR]

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The commercial mining of fluorspar in St. Lawrence Newfoundland began in 1933. Miners who worked underground were exposed to high levels of radon progeny, especially before ventilation was introduced into the mines in 1960. The mean cumulative radon exposure for underground miners in this cohort was 380.9 working level months (WLM). A series of studies of this cohort have characterized the increased risks of lung cancer mortality due to radon. We have extended the follow-up of this cohort an additional 15 years to provide additional insights on the risks of low levels of radon exposure, and the modifying effects of time since exposure, age at first exposure, attained age, duration of exposure, and cigarette smoking. The cohort consisted of 1,735 underground and 315 male surface miners who, combined, accrued 81,650 person-years of follow-up. The mortality experience of the cohort was determined from 1950–2016 through record linkage to Canadian national death data. Individual-level estimates of exposure to radon progeny, in WLMs, were determined for each year of employment. We compared the mortality experience of the underground miners to Newfoundland men using the standardized mortality ratio (SMR). Poisson regression models were fit to estimate excess relative risks (ERR) per 100 WLM. There were 236 lung cancer deaths identified, and of these, 221 occurred among underground workers. The SMR for lung cancer among underground miners compared to Newfoundland men was 2.67 (95% CI: 2.33, 3.04). The ERR per 100 WLM for lung cancer mortality, assuming a 5-year exposure lag, was 0.41 (95% CI: 0.23, 0.59). Attained age and time since exposure were important modifiers to the radon-lung cancer relationship. The joint relationship between smoking and radon on lung cancer risk was sub-additive, however, the smoking data were limited and available for only half of the cohort. [ABSTRACT FROM AUTHOR]

Barite is a primary source of barium, which is usually recovered by flotation. However, barite and fluorite, calcite and other embedded particle size is dense, often in the form of symbiosis, it is difficult to get efficient recovery from such mixed ore; and with the increase of mineral demand, efficient flotation separation is facing great challenges; Therefore, how to effectively improve the utilization value of barite has become the focus. Flotation reagent is the main research direction of barite flotation. Therefore, This study concentration on elucidation the adsorption mechanism and its influencing factors between collectors, collectors and minerals. It is pointed out that the essence of collector adsorption is the cationic action of the hydrophilic group and the mineral surface, which offsets a part of the residual bond force and weakens the alkylation of the mineral surface, thereby reducing the hydrophilicity of the mineral surface and improving the flotation effect. Secondly, the currently known inhibitors are briefly described. Subsequently, the properties of the collector were preliminarily characterized by calculation and analysis methods, and the theory was popularized to enhanced guidance the production. [ABSTRACT FROM AUTHOR]

Er3+-doped fluorite crystals, including CaF2 and SrF2, are considered as attractive laser gain materials in the mid-infrared (MIR) region with merits of high laser efficiency as well as low doping concentration. In this work, a series of Er, La:CaF2 crystals were grown and the modulation effect of co-doping La3+ ions on the spectral properties and mid-infrared laser performance was investigated. It was found that introducing La3+ ions can effectively manipulate the coordination environment of Er3+ ions embedded in CaF2 crystal, thus modulating the shape and intensity of absorption and emission bands. On the other hand, La3+ ions can partially substitute Er3+ sites in the clusters to form mixed clusters, which affects the energy transfer processes between Er3+ ions as well as ~3 μm laser performance, which is dominated by energy transfer up-conversion (ETU) processes between Er3+ ions. By co-doping La3+ ions into Er:CaF2 crystal at an appropriate concentration, the spectral parameter modulation can be achieved while maintaining a high MIR laser efficiency. [ABSTRACT FROM AUTHOR]

High-entropy oxides have recently attracted the interest of the community as a way of attuning the properties of oxides to energy applications. Here, we employ molecular dynamics simulations combined with empirical pair potential models to examine the predicted oxygen diffusivity of fluorite-structured high-entropy oxides. We show that lower levels of the dopants increase the overall diffusivity of the composition, but not to the levels of diffusion seen in yttria-doped zirconia. We attribute this to an increased resistance of the cation sublattice to the distortion that occurs through any multiple substitutions on the cation sublattice. To conclude, it is calculated that oxygen self-diffusion in high-entropy oxides is suppressed as compared to isostructural ternary oxides. [ABSTRACT FROM AUTHOR]

The maximum values of the mobility and concentration of charge carriers in fluoride superionic conductors of the fluorite (CaF2, SrF2, BaF2, and PbF2) and tysonite (LaF3) structural types have been calculated within the crystallophysical model. It is shown that the upper limits of the ionic conductivity and carrier mobility and concentration in the crystalline state of fluoride superionics are, respectively, 4 ± 1 S/cm, (5 ± 1) × 10−3 cm2/(V s), and (5 ± 2) × 1021 cm−3 (10 ± 4% of the total amount of fluorine ions). [ABSTRACT FROM AUTHOR]

This article considers the features and fundamental difficulties of studying low-temperature phase equilibria associated with an exponential increase in the required duration of syntheses with a decrease in temperature. Methods for accelerating the achievement of equilibrium, including the use of salt solvents, are also considered. The results of phase equilibria studies in the SrF2–LaF3 system using sodium nitrate and in the ZrO2–Sc2O3 system using sodium sulfate as fluxes are presented. The methods of extrapolation of phase diagrams to absolute zero temperature in accordance with the third law of thermodynamics are considered. Phase diagrams of the Au–Cu, Cu–Pd, Ni–Pt, and ZrO2–Y2O3 systems are presented. Phase equilibria with plagioclase ordering are considered separately, and the phase diagram of the albite–anorthite (NaAlSi3O8–CaAl2Si2O8) system is presented. As the temperature approaches absolute zero, the homogeneity region of labradorite shrinks to the compound NaCaAl3Si5O16. [ABSTRACT FROM AUTHOR]

The ionic mobility and conductivity of composites and compounds of the eutectic and close composition obtained by different methods in the PbF2–SnF2 system are studied based on the 19F NMR and impedance data. The stages of transformation of the 19F NMR spectra of these samples, their connection with the types of ionic movements, and the possible factors determining their ionic conductivity are considered. It is shown that the composition of the majority of composites includes the fluorite phase characterized by the high values of ionic mobility and conductivity. In the region close to the eutectic, a single-phase sample with the fluorite structure is obtained for the first time. The conductivity of this phase (5 × 10–3 S/cm at 390 K) makes it possible to consider it as the basis for synthesizing functional materials. [ABSTRACT FROM AUTHOR]

In this study, two high-entropy ceramics, namely (La 0.2 Nd 0.2 Sm 0.2 Eu 0.2 Gd 0.2) 2 Zr 2 O 7 (LaHZ) and (Nd 0.2 Sm 0.2 Eu 0.2 Gd 0.2 Yb 0.2) 2 Zr 2 O 7 (YbHZ), were prepared and investigated, in comparison to La 2 Zr 2 O 7 (LZ). This investigation focused on their interactions with calcium-magnesium-alumina-silicate (CMAS), revealing noteworthy findings. High entropy samples particularly YbHZ exhibit significantly reduced infiltration depths compared to LZ. After CMAS corrosion, the reaction zones of LaHZ and LZ show a similar microstructure characterized by the presence of apatite and fluorite embedded in CMAS residue. In contrast, YbHZ forms a dense and nanoscale dual-phase zirconia (fluorite + pyrochlore) layer, with no visible CMAS residue. The different corrosion behavior is associated with the competition between fluorite and apatite phases, which is strongly related to the ionic radius of RE3+. Apart from the apatite, the formation of a dense and continuous fluorite Ca&RE-ZrO 2 layer could also provide excellent CMAS resistance. These findings provide a viable strategy for designing CMAS-resistant materials. [ABSTRACT FROM AUTHOR]

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Flotation separation of calcite from fluorite is a challenge on low-grade fluorite flotation that limits the recovery and purity of fluorite concentrate. A new acid leaching–flotation process for fluorite is proposed in this work. This innovative process raised the fluorite's grade to 97.26wt% while producing nanoscale calcium carbonate from its leachate, which contained plenty of calcium ions. On the production of nanoscale calcium carbonate, the impacts of concentration, temperature, and titration rate were examined. By modifying the process conditions and utilizing crystal conditioning agents, calcite-type and amorphous calcium carbonates with corresponding particle sizes of 1.823 and 1.511 µm were produced. The influence of the impurity ions Mn2+, Mg2+, and Fe3+ was demonstrated to reduce the particle size of nanoscale calcium carbonate and make crystal shape easier to manage in the fluorite leach solution system compared with the calcium chloride solution. The combination of the acid leaching–flotation process and the nanoscale calcium carbonate preparation method improved the grade of fluorite while recovering calcite resources, thus presenting a novel idea for the effective and clean usage of low-quality fluorite resources with embedded microfine particles. [ABSTRACT FROM AUTHOR]

Herein, we synthesised a series of nonstoichiometric Nd−Ce−O composite oxides with a fluorite or rare‐earth C‐type phase structure using the glycine combustion method for the oxidative coupling of methane (OCM) reaction. As the amount of Nd3+ increases, the oxygen vacancies in this series of composite oxides gradually increase, leading to an amount increasing in the C2‐selective oxygen species O2− generated by the oxygen vacancies. In addition, with the increase in Nd3+, the number of moderate basic sites on the catalyst surface also improves, another significant factor affecting the OCM reaction performance of the composite oxides. Nd0.9Ce0.1O1.55 possesses optimal low‐temperature OCM reaction performance, achieving 8.0 % C2 yield at 450 °C and 14.1 % C2 yield at 700 °C. This can be attributed to the nonstoichiometric rare‐earth C‐type crystalline phase structure of Nd0.9Ce0.1O1.55, which exhibits the highest abundance of oxygen vacancies, selective oxygen species O2−, and moderate basic sites. [ABSTRACT FROM AUTHOR]

A2B2O7 oxides comprise four subcrystalline phase structures, which include the layered perovskite, pyrochlore, disordered defect fluorite, and rare‐earth C‐type structures. Herein, a series of A2B2O7 oxides have been synthesized using simple methods, and the X‐ray diffraction (XRD) and Raman spectroscopic characteristics of their subcrystalline phase structures are systematically summarized. It was found that the rA/rB ratio can be used to correctly determine the subcrystalline phase structure of the A2B2O7 oxides when the A‐site ions are rare‐earth ions. Although the A‐site ions are the main‐group metal ions, the rA/rB ratio cannot be used to accurately determine probably due to f electrons. Raman spectroscopy proves to be the most effective method for determining the subcrystalline phase structure, which is followed by XRD. The characteristic Raman spectral bands of disordered defect fluorites are closely related to their B‐site ion oxides with fluorite phase structures. For these A2B2O7 oxides with rA/rB ratios located at the edge value possessing the same elemental composition, different subcrystalline phase structures have been prepared by adopting different synthesis methods and calcination temperatures. The crystal phase of A2B2O7 oxides comprising two types of subcrystalline structures with a lower disorder degree is more stable at high temperatures. [ABSTRACT FROM AUTHOR]

Boronate esters are a class of compounds containing a boron atom bonded to two oxygen atoms in an ester group, often being used as precursors in the synthesis of other materials. The characterization of the structure and properties of esters is usually carried out by UV-visible, infrared, and nuclear magnetic resonance (NMR) spectroscopic techniques. With the aim to better understand our experimental data, in this article, the density functional theory (DFT) is used to analyze the UV-visible and infrared spectra, as well as the isotropic shielding and chemical shifts of the hydrogen atoms 1H, carbon 13C and boron 11B in the compound 4-(4,4,5,5-tetramethyl-1,3,2-dioxoborolan-2-yl)benzaldehyde. Furthermore, this study considers the change in its electronic and spectroscopic properties of this particular ester, when its boron atom is coordinated with a fluoride anion. The calculations were carried out using the LSDA and B3LYP functionals in Gaussian-16, and PBE in CASTEP. The results show that the B3LYP functional gives the best approximation to the experimental data. The formation of a coordinated covalent B–F bond highlights the remarkable sensitivity of the NMR chemical shifts of carbon, oxygen, and boron atoms and their surroundings. Furthermore, this bond also highlights the changes in the electron transitions bands n → π* and π → π* during the absorption and emission of a photon in the UV-vis, and in the stretching bands of the C=C bonds, and bending of BO2 in the infrared spectrum. This study not only contributes to the understanding of the properties of boronate esters but also provides important information on the interactions and responses optoelectronic of the compound when is bonded to a fluorine atom. [ABSTRACT FROM AUTHOR]

Optically transparent single-crystal blocks are prepared by the fusion of a barium fluoride charge with yttrium and erbium fluorides using sodium fluoride as a flux. The crystal structures were solved and composition of the following phases were determined: Na0.75Ba1.26Er1.99F9.24 (cubic crystal system, space group, a = 11.4192(4) Å), Na0.25BaY2.75F10.5 (cubic crystal system, space group, a = 11.4350(19) Å), Na0.05Ba0.9Y1.05F5 (orthorhombic crystal system, Cmmm space group, a = 5.7205(5) Å, b = 17.2348(11) Å, c = 5.7648 (4) Å). [ABSTRACT FROM AUTHOR]

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Water samples were collected during freezing and flowing conditions from eight sites along the Baotou section of the Yellow River. The main aims of this study were to obtain information on the fluoranthene concentrations in freezing-thawing process; to determine how fluoranthene concentrations were distributed in water; to discuss the photodegradation of fluor anthene in the water phase; to investigate the influence of light-sensitive materials (H2O2, acetone and sediment) on the photo degradation of fluoranthene in the water phase. The results indicated that fluoranthene concentrations were relatively high at sites S2 and S5, and residue levels were lower at points S4, S6 and S7. The fluoranthene light experiment was carried out under exposure to UV light with low fluoranthene concentrations, using a light conversion function in the water and ice phase, after 72 h the concentration the degradation rate reached 90%. The degradation rates of fluoranthene in water phase were lower with acetone, sediment and low concentrations of H2O2 than without, and the fluoranthene degradation was consistent with a first-order kinetics reaction, likewise, high H2O2 concentrations promoted photoconversion. [ABSTRACT FROM AUTHOR]

Films of ferroelectric hafnia have hitherto been deposited on electrodes with a non‐fluorite crystal structure. As a result, they are polycrystalline, contain fractions of non‐ferroelectric polymorphs or have poor crystal quality. Here, a strategy that circumvents all these limitations is shown. Seven nanometers‐thick epitaxial Hf0.5Zr0.5O2 (HZO) films are deposited directly on yttria‐stabilized zirconia (YSZ) single‐crystals. The fluorite structure of the whole system enables coherent epitaxy, while the substrate orientation induces polymorph‐selective growth, being the HZO films orthorhombic on YSZ(111) and monoclinic on YSZ(001). Besides, the YSZ substrate can play the role of a buried floating electrode under the appropriate measuring conditions (temperature and frequency) thanks to its thermally‐activated oxygen conductivity. Indeed, out‐of‐plane ferroelectric switching is confirmed in the orthorhombic HZO samples at 185 °C and 0.01 Hz frequency. This original approach avoids the need to deposit conducting bottom layers, allowing high‐quality orthorhombic hafnia to be obtained directly on the substrate and its ferroelectric nature to be studied. Moreover, it constitutes a case of ion‐driven ferroelectric switching, and thus gives support to the recently proposed relationship between ionic conductivity, and ferroelectricity in fluorite systems. [ABSTRACT FROM AUTHOR]

It is challenging to separate fluorite from calcite due to their same calcium activated sites on their surfaces. The copolymer of maleic and acylic acid (PMAA) was used to inhibit the calcite in the flotation of fluorite. Micro-flotation results exhibited that sodium oleate (NaOl) had a good ability to collect fluorite and calcite in the scope of pH 7-10. The PMAA treatment prior to NaOl selectively depressed the floatability of calcite while allowed the flotation of fluorite, and the artificial minerals mixture plotted that fluorite/calcite could be effectively separated in the presence of PMAA/NaOl. Zeta potential results suggested that NaOl collector was absorbed on the PMAA-conditioned calcite surface but did not adsorb on the PMAA-conditioned fluorite surface. XPS results and calculational chemistry revealed the chemical interaction occurred between calcite surface and PMAA which was attributed to the calcium ions of calcite surface interacting with -COOH group of PMAA. [ABSTRACT FROM AUTHOR]

The prominence of hydrogen energy has brought membrane separation technology to forefront attention. La 2 Ce 2 O 7 , possessing a fluorite structure, exhibits notable stability in both H 2 O and CO 2 , rendering it a prospective material for membrane separation. The impact of Sr doping on the electrochemical characteristics of La 2 Ce 2 O 7 was systematically investigated. The findings indicate that a minor addition of Sr2+ through doping enhances the electrical conductivity, with the most significant improvement observed in La 2-x Sr x Ce 2 O 7-δ (x = 0, 0.05, 0.15, 0.30) when doped by 0.05. Elevated temperature and increased hydrogen partial pressure on the feed side enhance hydrogen permeability. Hydrogen permeation is predominantly governed by bulk diffusion when the membrane thickness exceeds 0.59 mm, while for thicknesses below 0.49 mm, the process is influenced by both surface and bulk diffusion. Moreover, the doped La 2 Ce 2 O 7 exhibit commendable stability in H 2 O and CO 2 environments. Consequently, La 2 Ce 2 O 7 emerges as a promising candidate for ceramic hydrogen separation membranes. • The impact of Sr doping on the electrochemical characteristics of La 2 Ce 2 O 7. • Sr doping increases the oxygen vacancy concentration and conductivity of La 2 Ce 2 O 7. • Pt–La 1.7 Sr 0.3 Ce 2 O 7-δ exhibits the highest hydrogen permeation flux. • The samples are stable at boiling water and CO 2 atmosphere at 900 °C. [ABSTRACT FROM AUTHOR]

The congruent melting compositions in the MF2–M'F2–RF3 systems (M ≠ M' = Ca, Sr, Cd, Ba, Pb; R are rare-earth elements (REEs)) have been determined based on thermodynamic topological analysis. Crystals of fluorite solid solution in the PbF2–CdF2–RF3 (R = Tb, Ho, Er, Tm, Yb, Lu) systems were grown by the vertical directional crystallization technique. Their phase composition and distribution of components over the crystalline boule length were investigated. Crystals of congruently melting solid solutions (Pb0.67Cd0.33) RxF (R = Tb, Ho, Er, Tm, Yb, Lu) were grown for the first time. Traces of low-temperature transformation—a phase isostructural to the Pb2YF7 compound (sp. gr. I4/m), in which Y sites are occupied by the corresponding R cations and Pb sites can be partially occupied by Cd cations—were found in the crystals with R = Ho, Er, Tm, and Yb. The crystals with R = Tb and Lu have a high degree of homogeneity and are suitable for optical studies. [ABSTRACT FROM AUTHOR]

New data on roméite (CaNa)Sb2O6F solubility in the NaF–H2O system of P–Q type have been obtained within a wide range of sodium fluoride concentrations (from 0 to 25 wt % NaF). The concentration of antimony, in equilibrium with roméite and fluorite, in the range of NaF concentrations from 1 to 8 mol kg–1 H2O (25 wt % NaF), is in the range of 0.02–0.2 mol kg–1 H2O. According to the data, the concentration of antimony in phases L1 and L2 in the region of fluid immiscibility of the NaF–H2O system at 800°C, 200 MPa and fO2 = 50 Pa, specified by the Cu2O–CuO buffer, is 0.4 and 2.1 wt % Sb, respectively. Our experiments were the first ever to produce skeletal fluorite crystals and the intermetallic compound Pt5Sb, which belongs the hexagonal crystal system and has the following lattice parameters (LP): a = b = 4.56(4) Å, c = 4.229(2) Å, and α = β = 90°, γ = 120°. Pentaplatinum antimonide was formed on the inner surface of the Pt capsules at 800°C, Р = 200 MPa, and fO2 ≤ 10–3.47 Pa (Cu–Cu2O buffer) in experiments on the incongruent dissolution of roméite, which causes a sharp decrease (more than 1000 times) in antimony concentration in the solution. [ABSTRACT FROM AUTHOR]

Fluorite-dominated rocks are occasionally found in association with carbonatites, but their geologic and petrologic relations are rarely reported. The Dunkeldyk area of the Pamir mountains in south-eastern Tajikistan contains dikes of distinctive rocks composed of calcite, fluorite, celestine-barite, sulfides, apatite, with minor quartz, biotite, and REE fluorcarbonates. The dikes have sharp contacts with the host (meta-)sedimentary rocks and layering with ribbons, ranging from fluorite-bearing calcite carbonatites to fluoritites (rocks with >50% fluorite). The fluoritites are characterized by high Ca, F, Ba, Sr, REE, and S coupled with anomalously low O. The geologic relations and textures suggest a magmatic origin of the dikes from melts close to calcite–fluorite eutectic that experienced nucleation-controlled differentiation during the crystallization of dikes and the formation of fluoritite cumulates in larger intrusions. The Dunkeldyk dikes demonstrate that sizable geological bodies of fluorite-dominated rocks could form from carbonate–fluoride melts originating from the differentiation of alkaline silicate magmas. [ABSTRACT FROM AUTHOR]

This study addresses the in situ mobility of fluoride and aluminum in two different ashfall deposits accumulated during the 2021 eruption of the Tajogaite volcano (La Palma, Canary Islands, Spain), which were exposed to contrasting conditions of ambient humidity and precipitation. We selected one site to the east of the volcanic emission center, located near the top of Cumbre Vieja Ridge and exposed to continuous humidity and rain, and another site to the west of the volcano situated in a lowland and characterized by much drier conditions. The mobility of fluoride and aluminum is markedly different at both sites, with the first sequence suggesting a downwards migration of Al and F, and the second sequence showing no sign of mobility. The migration of aluminum and fluorine results from the dissolution of different fluoride salts (mostly AlF3 and CaF2, as suggested by scanning electron microscopy) followed by vertical transport as ionic complexes (AlF3, AlF2+, AlF4−) during the percolation of rainwater through the ashfall deposits. Geochemical calculations suggest that the mobility of fluorine at neutral to alkaline conditions (pH 7.0–9.0) is likely limited by the solubility of fluorite (CaF2), whereas at slightly acidic conditions (pH < 6.5), the aqueous concentration of aluminum seems to be controlled by the solubility of gibbsite (Al(OH)3). This study demonstrates that aluminum and fluoride can be transported from volcanic ash to the underlying soil or groundwater, which is an environmental concern that should be followed in the future. [ABSTRACT FROM AUTHOR]

Late Devonian felsic volcanic rocks of the Grand Beach complex (GBC) of Avalonia from the Burin Peninsula, southeastern Newfoundland (northwestern Appalachians) are part of an overstep sequence overlying the Neoproterozoic basement. The volcanic complex is composed of volcanic and volcaniclastic rocks deposited in a post-tectonic extensional setting proximal to the St. Lawrence granite (SLG), a Devonian pluton associated with a prominent vein-type fluorite mineralization. The volcanic rocks are alkali rhyolites, which are weakly peraluminous and exhibit geochemical characteristics of A-type felsic magmas, such as low FeOt, MgO, CaO, and TiO2 but high contents of alkalis, Nb, Y, and Zr and high Ga/Al and FeOt/MgO ratios. They have positive ɛNd(t) values (~ + 2.5) and their Nd-depleted mantle model ages (~ 0.9 Ga) are consistent with derivation of the parental magma from metasomatized dry Avalonian lower crustal basement via partial melting followed by fractional crystallization. The U–Pb zircon age for the volcanic complex (375.6 ± 1.1 Ma) is closely comparable to the age of the SLG, suggesting that they were emplaced during the same magmatic episode. They also have similar chemical and isotopic compositions, suggesting that the GBC represents a volcanic equivalent of the SLG. The compositional differences between the volcanic rocks and the main phase of the granite pluton, including higher oxidation state of the GBC, reflect the interaction of the parental magma with crustal material and fluids. The close proximity of SLG and GBC suggests that the volcanic complex could host fluorite mineralization. [ABSTRACT FROM AUTHOR]

High-temperature calcium-magnesium-alumina-silicate (CMAS) attack has become a fatal factor hindering the development of thermal barrier coatings (TBCs). In this study, a promising entropy-stabilized (La 0.2 Nd 0.2 Sm 0.2 Eu 0.2 Gd 0.2) 2 Hf 2 O 7 (5LaH) hafnate was synthesized and prepared successfully, and then the CMAS corrosion behavior was investigated. During the corrosion process, the precipitation of the apatite phase causing the aggregation of Hf4+ promotes the formation of the (Hf, Si)O 2 phase to generate a dense structure layer, which has a great barrier effect on the penetration of CMAS melt, and apatite phase with the entropy effect proves the stability of the reaction layer. Moreover, molten CMAS is less inclined to wetting and spreading on 5LaH surfaces compared to YSZ, which is also beneficial to the CMAS corrosion resistance. In general, the 5LaH exhibits great anti-CMAS corrosion performance. [ABSTRACT FROM AUTHOR]

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