Technology of Ferroalloys with Alkaline-Earth Metals

Gasik, Mikhail

doi:10.1016/b978-0-08-097753-9.00019-8

Cited by 6 publications

(4 citation statements)

References 2 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Particularly, before the introduction of an electric arc furnace, producing silicides of a grade higher than Si-15 wt% in a blast furnace was impossible (Greiner et al 1933). Impurities in the production of calcium carbide (CaS, Ca 3 P 2 , Al 2 0 3 , Si0 2 , SiC), invoked by Spencer (1935) to explain silicide occurrences without due examination, have not included iron silicide and were removed by technological requirements during the production process (White 1928;Gasik 2013). Synthetic iron silicides, manufactured widely since the 1950s, are homogeneous equilibrated materials distinct from heterogeneous composition and complex petrology of iron silicide spherules occurring in natural settings.…”

Section: Originmentioning

confidence: 99%

Constraints on the origins of iron silicide spherules in ultrahigh‐temperature distal impact ejecta

Batovrin¹,

Lipovsky²,

Gulbin

et al. 2021

Meteorit & Planetary Scien

View full text Add to dashboard Cite

Terrestrially occurring iron silicide spherules, described in the geological literature for 160 years as cosmogenic and approved as "extraterrestrial" minerals by IMA CNMMN in 1984, so far have escaped any serious examination by meteoriticists. Our isotopic and REE data, obtained for silicide spherules for the first time, disagree with the meteoritic origin of gupeiite (Fe 3 Si) and xifengite (Fe 5 Si 3 ) spherules from two continents. Despite departures from terrestrial norms ( 87 Rb/ 86 Sr-0.0174; 87 Sr/ 86 Sr-0.700181; 3 He/ 4 He-7.57 × 10 −6 ; 40 Ar/ 36 Ar-325.9), the compositions of 143 Nd/ 144 Nd (0.512034) and 147 Sm/ 144 Nd (0.06357), as well as REE abundances, clarify provenance from upper crust sediments for samples with U/Pb age of 121-314 ka from the Ala-Tau range in the Urals. However, the morphology of flanged button shapes, ring waves, and eccentro-radiating ridges reliably constrains the origin of silicide spherules to distal meteoritic impact ejecta. Arc jet ablation experiments have previously demonstrated that similar morphologies, observed on australite tektites, reflect aerodynamic ablation rates corresponding to flight velocities well into orbital range. These features are generally accepted as conclusive evidence for hypervelocity atmospheric entry from space. Internal structure, consistent with accretion through the coalescence of 3-5 µm droplets, and composition, closely corresponding to 1893-1154 K span of C-type condensation sequences, indicate a high probability of processing through recondensation of ejecta vapor.

show abstract

Section: Originmentioning

confidence: 99%

Constraints on the origins of iron silicide spherules in ultrahigh‐temperature distal impact ejecta

Batovrin¹,

Lipovsky²,

Gulbin

et al. 2021

Meteorit & Planetary Scien

View full text Add to dashboard Cite

show abstract

“…In previous works, barium (Ba) was used as a dopant for modifying the properties of many semiconductors such as CdO, ZnO, and TiO 2 for different applications. − Ba is a member of the alkaline earth metals, and it always exhibits an oxidation state of +2 . Ba can be used in many applications such as varistors, liquid sensors, fluorescent lamps, guiding layers, ceramics, optical glass, and rubber.…”

Section: Introductionmentioning

confidence: 99%

“…22−24 Ba is a member of the alkaline earth metals, and it always exhibits an oxidation state of +2. 25 Ba can be used in many applications such as varistors, liquid sensors, fluorescent lamps, guiding layers, ceramics, optical glass, and rubber. Ba 2+ ion has an ionic radius of 1.35 Å, which is greater than that of Cu 2+ (0.73 Å) ion.…”

Section: ■ Introductionmentioning

confidence: 99%

Simple and Low-Cost Synthesis of Ba-Doped CuO Thin Films for Highly Efficient Solar Generation of Hydrogen

2020

View full text Add to dashboard Cite

Hydrogen gas is an eco-friendly energy source that can be directly converted to electricity using fuel cells. In this work, CuO and Ba-doped CuO thin films were prepared on glass substrates using a simple successive ionic layer adsorption and reaction (SILAR) method for hydrogen production. For pure and doped films, the (−111) plane was the preferred crystallographic orientation. The bandgap of the pure CuO film was tuned from 1.63 to 1.87 eV after incorporating 6% Ba. The average nanoparticle size of the pure CuO film was reduced from ∼195 to ∼100 nm and then to 90 nm as the Ba doping ratio was increased from 2 to 4%. The pure and doped CuO films were composed of a random distribution of nanoparticles in an irregular form, as demonstrated by scanning electron microscopy (SEM). Energy-dispersive X-ray spectroscopy (EDX) patterns demonstrated the high purity of the deposited films and the rise of the Ba atomic % from 0.21 to 0.82 by increasing the doping level to 6%. The 2% Ba-doped CuO films showed a high photocatalytic performance as a photoelectrode for efficient hydrogen generation. The Ba-doped CuO film displayed the best performance for the water-splitting reaction (photocurrent density J = 17 mA/cm 2 ) with long-term stability against photocorrosion. The conversion efficiencies incident photon-to-current efficiency (IPCE) and applied bias photon-to-current efficiency (ABPE) were 39.6% at 440 nm and 5.75% at 0.41 V, respectively. Consequently, our work introduced an efficient and cost-effective photocathodic material for practical and industrial hydrogen production.

show abstract

“…CaSi 2 is utilized in various applications, serving as a deoxidizer and desulfurizer in steel production, as well as a reactive primer in firearm cartridges . In the field of material research, the significance of CaSi 2 lies in its crystal structure, which features infinite 2D silicon layers .…”

Section: Introductionmentioning

confidence: 99%

Deciphering the Polymorphism of CaSi₂: The Influence of Heat and Composition

Feng,

Carrillo-Cabrera,

Ormeci

et al. 2024

Inorg. Chem.

View full text Add to dashboard Cite

The Zintl phase CaSi 2 is a layered compound with stacking variants known as 1P, 3R, and 6R. We extend the series by the 21R polytype formed by rapid cooling of the melt. The crystal structure of 21R-CaSi 2 (space group R3̅ m) was derived from HRTEM images, and the atomic positions were optimized by using the FPLO code (a = 3.868 Å, c = 107.276 Å). We explore polytype transformations by powder X-ray diffraction (PXRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), electron backscattering diffraction (EBSD), and thermal analysis. While 6R-CaSi 2 is thermodynamically stable at ambient conditions, nanosized impurities of silicon stabilize 3R-CaSi 2 as a bulk phase.

show abstract

Technology of Ferroalloys with Alkaline-Earth Metals

Cited by 6 publications

References 2 publications

Constraints on the origins of iron silicide spherules in ultrahigh‐temperature distal impact ejecta

Constraints on the origins of iron silicide spherules in ultrahigh‐temperature distal impact ejecta

Simple and Low-Cost Synthesis of Ba-Doped CuO Thin Films for Highly Efficient Solar Generation of Hydrogen

Deciphering the Polymorphism of CaSi₂: The Influence of Heat and Composition

Contact Info

Product

Resources

About

Technology of Ferroalloys with Alkaline-Earth Metals

Cited by 6 publications

References 2 publications

Constraints on the origins of iron silicide spherules in ultrahigh‐temperature distal impact ejecta

Constraints on the origins of iron silicide spherules in ultrahigh‐temperature distal impact ejecta

Simple and Low-Cost Synthesis of Ba-Doped CuO Thin Films for Highly Efficient Solar Generation of Hydrogen

Deciphering the Polymorphism of CaSi2: The Influence of Heat and Composition

Contact Info

Product

Resources

About

Deciphering the Polymorphism of CaSi₂: The Influence of Heat and Composition