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The heat capacity of yttrium(III) bromide (YBr3) in the temperature range from 2 K to 300 K has been determined using a Physical Property Measurement System (PPMS). From these data the absolute entropy of the compound at 298.15 K has been derived. [ABSTRACT FROM AUTHOR]

The use of low-fluence picosecond (LFPS) 1064 nm neodymium-doped yttrium aluminum garnet (Nd:YAG) lasers, referred to as laser toning, is increasingly acknowledged as an effective treatment for pigmentation disorders in the Asian skin phenotype. This study aimed to conduct a comparative analysis on the effectiveness and safety of utilizing LFPS 1064 nm Nd:YAG lasers against picosecond 532 nm Nd:YAG lasers in treating pigmented lesions among Chinese patients. A retrospective photographic analysis and chart reviews were performed on 31 subjects exhibiting Fitzpatrick skin types III–VI who underwent LFPS 1064 nm Nd:YAG or picosecond 532 nm Nd:YAG treatments at a single tertiary center. Utilizing VISIA Complexion Analysis, comparative photographs were taken. Two independent physicians evaluated treatment efficacy using a visual analog scale (VAS) to assess the percentage of pigmentary clearance in standard photographs. Solar lentigines were the most prevalent pigmentary disorder, followed by post-inflammatory hyperpigmentation (PIH), nevus zygomaticus, melasma, freckles, and nevus of Ota. The clinical effectiveness of picosecond 532 nm and LFPS 1064 nm laser treatments proved comparable for lesions on the face, with mean VAS scores of 2.2 ± 1.1 and 1.8 ± 0.8, respectively. There were two cases of PIH in the picosecond 532 nm group, which resolved within one month. Overall, the LFPS 1064 nm laser demonstrates promise as a safe and efficient therapeutic modality for managing pigmented lesions in Chinese patients. [ABSTRACT FROM AUTHOR]

To improve our understanding and guide future studies and applications, we review the biogeochemistry of the rare earth elements (REE). The REEs, which form a chemically uniform group due to their nearly identical physicochemical properties, include the lanthanide series elements plus scandium (Sc) and yttrium (Y). These elements, in conjunction with the neodymium isotopes, are powerful tools for understanding key oceanic, terrestrial, biological and even anthropogenic processes. Furthermore, their unique properties render them essential for various technological processes and products. Here, we delve into the characteristics of REE biogeochemistry and discuss normalization procedures and REE anomalies. We also examine the aqueous speciation of REEs, contributing to a better understanding of their behavior in aquatic settings, including the role of neodymium isotopes. We then focus on their environmental distribution, fractionation, and controlling processes in different environmental systems across the land‐ocean continuum. In addition, we analyze sinks, sources, and the mobility of REEs, providing insights into their behavior in these environments. We further investigate the sources of anthropogenic REEs and their bioavailability, bioaccumulation, and transfer along food webs. We also explore the potential effects of climate change on the cycling, mobility and bioavailability of REEs, underlining the importance of current research in this evolving field. In summary, we provide a comprehensive review of REE behavior in the environment, from their properties and roles to their distribution and anthropogenic impacts, offering valuable insights and pinpointing key knowledge gaps. Key Points: Rare earth elements (REE) are powerful tracers of both natural and anthropogenic processes within terrestrial and ocean environmentsREE are controlled by absorption, adsorption/desorption, co‐precipitation, remineralization, and particle dissolutionREE are technology‐critical metals with broad applications in the future low‐carbon global economy [ABSTRACT FROM AUTHOR]

In this paper, we present the characteristics of photoluminescent YBO3 successfully synthesized through a solid-state reaction and a microwave-assisted method. We used yttrium oxide and boric acid in excess as the starting reagents. The synthesis conditions were reflected in the fluorescent characteristics and the structure. Excess boric acid caused structural changes, as observed by the FTIR spectroscopy analysis. Powder X-ray diffraction (XRD) analysis confirmed the crystalline phases and purity of the samples. We observed improved photoluminescence properties in the samples synthesized by the microwave-assisted method. These findings enhance the understanding of the material's properties and indicate potential applications in illumination, displays, and narrow-band fluorescent smartphone-readable markers. [ABSTRACT FROM AUTHOR]

Pure magnesium and Mg-(0.2-0.9 at%) Y rolled sheets were subjected to three-point bending tests to individually investigate the effects of texture and yttrium addition on bending deformation behavior. Yttrium addition increased bending yield stress in both Specimen TR with the neutral plane parallel to the ND (normal direction of the rolled sheets) plane and Specimen TN with the neutral plane perpendicular to the ND plane, resulting from the increase in critical resolved shear stresses (CRSSs) for basal slip and f10-12g twinning with yttrium addition. Bending ductility increased with increasing yttrium addition until 0.5 at% yttrium addition, and then decreased at 0.9 at% yttrium addition in Specimen TN. On the other hand, bending ductility increased until 0.9 at% yttrium addition in Specimen TR since non-basal slip activities increased with increasing yttrium addition. Since the neutral plane in Specimen TN with 0.9 at% yttrium addition moved more to the center than that in Specimen TN with 0.5 at% yttrium addition, resulting in the higher tensile strain at the tension side. Therefore, the bending ductility in 0.9 at% yttrium addition was lower than that in 0.5 at% yttrium addition. [ABSTRACT FROM AUTHOR]

Rare earth elements are a group of chemicals widely utilized in industry, leading to ecosystem contamination. Due to the lack of regulatory measures, there exists a considerable gap in knowledge concerning their potential to induce adverse effects in organisms. Zebrafish serve as a species utilized in evaluating the risk of potentially toxic substances in the aquatic ecosystem. Our objective was to evaluate the acute toxicity in zebrafish embryos induced by two of the most used rare earth elements, neodymium, categorized as a light element, and yttrium, as a heavy element. We followed OECD guideline n°. 236 "Fish Embryo Acute Toxicity Test", exposing embryos to concentrations of 6.4, 16, 40, 100, and 250 mg/L, and calculated the LC50. Our study revealed comparable LC50 values for both elements (55.58 mg/L for Nd, and 45.61 mg/L for Y), suggesting a probable similarity in toxicity. These concentrations values have previously been identified in various contaminated regions globally, presenting a cause for concern. [ABSTRACT FROM AUTHOR]

The electronic, phonon, and superconducting properties of hexagonal yttrium hydrogen selenide (YHSe) are studied using density functional theory (DFT) methods. The DFT analysis revealed that the energy bandgap and density of states near the Fermi energy (ɛF) decrease with increasing pressure. Additionally, the influence of pressure on the vibrational properties of YHSe is also examined. The findings of the vibrational properties indicate a stiffening of lattice dynamics under pressure and the identification of negative Gruneisen parameters at certain high symmetry sites. This enhances and deepens the understanding of the vibrational characteristics of YHSe under extreme pressure conditions. Finally, the electron–phonon coupling (EPC) parameter (λ) is examined under different pressures. The examination of EPCs across varying pressures showed a significant increase from 0.826 (0 GPa) to 2.6287 (200 GPa), where an increase in this EPC is found to increase the superconducting critical temperature (Tc). Furthermore, the nonmonotonic relationship between the superconducting critical temperature (Tc) and external pressure (P) in the YHSe compound is observed. Initially, Tc decreases with increasing pressure and then begins to rise again, reaching its peak value at extreme pressure. These findings provide valuable insights into the pressure-dependent properties of YHSe and have important implications for the field of superconductivity in condensed matter physics. [ABSTRACT FROM AUTHOR]

A fast and simple method for the synthesis of solid solutions based on erbium-doped yttrium oxide (Y1–xErx)2O3 was developed. The crystal structures of the samples were determined by x-ray diffraction methods. The compounds exhibited greenish-yellow upconversion emission upon IR laser excitation (980 nm). An increase in the erbium concentration in (Y1–xErx)2O3 caused a color change and a growth in the intensity of the upconversion luminescence. The maximum upconversion luminescence intensity was observed for the oxide with x = 0.05. A two-photon excitation mechanism was determined based on the dependence of the emission line intensities associated with 2H11/2/4S3/2 → 4I15/2 and 4F9/2 → 4I15/2 transitions on the pumping power. The absolute and relative sensitivities were calculated from the temperature dependences of the ratio of emission lines corresponding to transitions from thermally coupled excited 2H11/2 and 4S3/2 levels and showed the promise of the oxides as materials for noncontact temperature sensing. [ABSTRACT FROM AUTHOR]

In this research work, nickel dioxide (NiO2) with a fixed quantity of graphitic carbon nitride (g-C3N4) and various concentrations of yttrium (Y) (2, 4 wt%) were synthesized via the coprecipitation method. The main objective is to degrade hazardous dyes such as Rhodamine B (RhB) with synthetic material and to assess antibacterial and catalytic activity with molecular docking analysis of the synthesized Y/g-C3N4-doped NiO2 nanostructures (NSs). A series of characterizations for optical, morphological, structural, and compositional analysis of prepared NSs were monitored to better understand the obtained samples. X-ray diffraction pattern evaluated the hexagonal structure of NiO2. Fourier transform infrared spectra demonstrated the prescence of bending and stretching vibration modes. Upon the incorporation of Y and g-C3N4, no visible transmittance shift was observed. The high resolution transmission electron microscopy micrographs affirmed the formation of agglomerated NiO2 NSs with few rod-like shapes, also assured by EDS elemental configuration. The UV–vis spectra revealed a redshift upon including Y and g-C3N4 into NiO2, leading the band gap energy to decrease from 3.6 to 3.4 eV. The catalytic efficacy of prepared samples was examined against Rhodamine B (RhB) dye in the prescence of reducing agent. In an acidic medium, the highest catalytic degradation rate of 99.85% was achieved by 4% Y/g-C3N4–NiO2, ascribed to increased production of H+ ions absorbed over the NSs surface. Moreover, the antimicrobial efficacy of synthesized NSs was evaluated against Escherichia coli (E.coli) bacteria and was observed as 3.15 mm. In silico docking studies of g-C3N4/NiO2 and Y/g-C3N4–NiO2 NSs for dihydrofolatereductase (DHFR) and dihydropteroate synthase (DHPS) of E.coli postulated inhibition of the enzymes above as a possible mechanism in addition to their microbicidal activity. [ABSTRACT FROM AUTHOR]

Lanthanides (Ln2O3) and elements like Zr and Y find application in the highest temperature‐resistant thermal and/or environmental barrier coatings. Such coatings are routinely exposed to silicate particles (e.g., sand, dust, volcanic ash), leading to chemical reactions that degrade the coating. The dissolution of 13.5 wt.% Ln2O3 into a calcium–magnesium–aluminum‐silicate (CMAS) melt leads to a viscosity reduction for the light lanthanides, while viscosity increases toward heavier lanthanides. For Gd, Y, and Zr, various amounts up to 13.5 wt.% (Gd2O3, Y2O3, ZrO2) were added to the CMAS melt, showing a tendency of increased viscosity for low concentrations (2.5‐3 wt.%) and a decreasing viscosity for higher values of the added component. [ABSTRACT FROM AUTHOR]

The chiral aziridine-containing vicinal iminophenol tridentate ligands (named salazins) are a class of readily prepared chiral ligands from enantiopure aziridines and salicylaldehydes. Their scandium and yttrium triflate complexes show excellent reactivity and enantioselectivities in the catalytic asymmetric aldol condensation of electron-deficient aromatic aldehydes and ketones, including acetone and cycloalkanones. The stereoselectivity is rationalized to the strong π–stacking interaction between aromatic aldehydes and the vicinal iminophenol group in the chiral ligands. [ABSTRACT FROM AUTHOR]

In this study, several types of zirconium-based alloys supplemented with 2, 3, and 4, in wt.% of yttrium for corrosion resistance enhancement were investigated. The specimens were prepared by a single arc welding furnace in an argon-controlled atmosphere. By optical and scanning electron microscopy, energy dispersive spectroscopy, X-ray diffraction, and electrochemical tests, the effect of different portions of yttrium on the surface morphology, phase structure, and corrosion resistance in the Zr alloys were analyzed. As of result of arc welding, the specimens were obtained and examined by optical microscope and then homogenous structures were observed. These structures are matrix (Zr-rich) and oxides. Furthermore, as of the characterization results by X-ray diffraction, the main compound of the alloys was Zr6Mo6AlTi, while others were AlZr3, MoO2, ZrO2, and Y2O3 oxides. Yttrium addition in the alloys prior to the corrosion test led to thickened grain boundaries but reduced grain size. The Y2O3 itself remained at the grain boundaries as clusters. The corrosion test was performed in Ringer's lactate solution by using anodic polarization. The effect of yttrium addition into Zr-based alloys was found to be beneficial by shifting the corrosion potential toward a positive value. Zr-6Mo-6Al-Ti-4Y had a higher open corrosion potential value than the other two alloys. The difference was approximately 200 mV. However, the passive region of Zr-6Mo-6Al-Ti-4Y was the shortest and broke down at an earlier stage. The formation of these kinds of oxides was the reason for the increase in corrosion potential of Zr-based alloys with 4% Y added. [ABSTRACT FROM AUTHOR]

The effect of 0.2%Cr addition on the structure, phase composition, and mechanical properties of the novel cast and wrought Al-2.5Zn-2.5Mg-2.5Cu-0.2Zr-Er(Y) alloys were investigated in detail. Chromium is distributed between primary crystals (5.7–6.8%) of the intermetallic phase and the aluminum solid solution (0.2%) (Al). The primary crystals contain for the main part Cr, Ti, Er(Y). The experimental phase composition is in good correlation with the thermodynamic computation data. The micron-sized solidification origin phases (Al8Cu4Er(or Y) and Mg2Si) and supersaturated (Al) with nano-sized Al3(Zr,Ti) and E (Al18Mg3Cr2) precipitates are presented in the microstructure of the novel alloys after solution treatment. The nucleation of η (MgZn2) (0.5%), S (Al2CuMg) (0.4%), and T (Al,Zn,Mg,Cu) (8.8%) phase precipitates at 180 °C, providing the achievement of a maximum hardness of 135 HV in the Al2.5Zn2.5Mg2.5CuYCr alloy. The corrosion potential of the novel alloy is similar to the Ecor of the referenced alloy, but the corrosion current density (0.68–0.98 µA/sm2) is still significantly lower due to the formation of E (Al18Mg3Cr2) precipitates and S phase precipitates of the aging origin, in addition to the T phase. The formation of E (Al18Mg3Cr2) precipitates under the solution treatment provides a lower proportion of recrystallized grains (2.5–5% vs. 22.4–25.1%) and higher hardness (110 HV vs. 85–95 HV) in the Cr-rich alloys compared to the referenced alloys. Solution treated, hot and cold rolled, recrystallized, water quenched and aged at 210 °C alloys demonstrate an excellent microstructure stability and tensile properties: YS = 299–300 MPa, UTS = 406–414 MPa, and El. = 9–12.3%. [ABSTRACT FROM AUTHOR]

Ammonia is pivotal to various chemical industries, which is produced using the Haber-Bosch process. This process requires harsh conditions (e.g., 20.0 MPa and (500–600)°C) to generate ammonia and thus, is an energy intensive process. The growing consensus is to mild the conditions for ammonia generation. Herein, we demonstrate the use of hydride to increase the activity of molybdenum carbonitride (MCN). YH@MCN (95:5, w/w) generates ammonia at a rate of 448 μ m o l g − 1 h − 1 at 255 °C and 0.1 MPa. To address the stability issue of hydride, we incorporate iron. The experiment demonstrates two-fold rates for such catalyst, comparing MCN alone. The activation energy (19.73kJmol-1) for YFeH@MCN is considerably low, owing to the electron transfer from YH to MCN that facilitates nitrogen dissociation. Hence, the use of distinct sites for easy dissociation of nitrogen molecules, and the synergy between them, results in an activity that exceeds of conventional molybdenum and iron-based catalysts, and is comparable to ruthenium-based catalysts. Our results illustrate the potential of using synergistic multiple active sites in catalysts, and introduce a design concept for ammonia synthesis catalysts, using readily available elements. • Low-temperature ammonia synthesis is performed using hydrides. • Hydride promotes catalytic activity of molybdenum carbonitride. • Hydrogen storage capacity of yttrium mixed with iron is examined. • YH@MCN generates ammonia at a rate of 448 μ m o l g − 1 h − 1 at 255 °C and 0.1 MPa. • Low activation energy (19.73kJmol-1) infers transfer of electrons from YH to MCN. [ABSTRACT FROM AUTHOR]

The intermolecular hydroamination of norbornene with simple amines was achieved using silyl‐substituted ortho‐terphenoxide yttrium complexes. Excellent conversion was obtained for both benzylic and aliphatic amines. For benzyl and linear aliphatic amines, the highest activity was observed for the sterically more encumbered methyldiphenylsilyl‐substituted complex, whereas the trimethylsilyl‐substituted complex was more active for sterically encumbered primary amines. [ABSTRACT FROM AUTHOR]

In this work, we present an advancement in the encapsulation of lithium yttrium fluoride-based (YLiF4:Yb,Er) upconversion nanocrystals (UCNPs) with silica (SiO2) shells through a reverse microemulsion technique, achieving UCNPs@SiO2 core/shell structures. Key parameters of this approach were optimized to eliminate the occurrence of core-free silica particles and ensure a controlled silica shell thickness growth on the UCNPs. The optimal conditions for this method were using 6 mg of UCNPs, 1.5 mL of Igepal CO-520, 0.25 mL of ammonia, and 50 μL of tetraethyl orthosilicate (TEOS), resulting in a uniform silica shell around UCNPs with a thickness of 8 nm. The optical characteristics of the silica-encased UCNPs were examined, confirming the retention of their intrinsic upconversion luminescence (UC). Furthermore, we developed a reliable strategy to avoid the coencapsulation of multiple UCNPs within a single silica shell. This approach led to a tenfold increase in the UC luminescence of the annealed particles compared to their nonannealed counterparts, under identical silica shell thickness and excitation conditions. This significant improvement addresses a critical challenge and amplifies the applicability of the resulting UCNPs@SiO2 core/shell structures in various fields. [ABSTRACT FROM AUTHOR]

This paper presents the analysis of electrical and dielectric properties of the yttrium-doped nickel ferrite nano-powders synthesized using the co-precipitation method. Impedance and dielectric measurements have been carried out as a function of frequency at different temperatures from 200 to 25 °C in the range of 0.1 kHz–1 MHz. In order to investigate the conduction mechanism and highlight the role of yttrium doping in different concentrations, impedance spectroscopy was employed. The obtained data were analyzed in terms of equivalent circuits made of resistor and capacitor components describing the contributions from different electrical active regions in a material. Further, this study highlights the importance of a single constant phase element (CPE) in the description of dispersion behavior of the impedance response of the investigated samples in the given frequency range. The use of this technique enabled the characterization of grain and grain boundaries contribution in overall conductivity mechanism. The dielectric dispersion nature of all investigated materials is reflected in this study. Very high values of the real part of permittivity at low frequencies are assigned to space-charge polarization. The dependence of the real part of dielectric permittivity values of the yttrium content was also discussed. Doping with yttrium in different concentrations that reflects in different electric and dielectric responses is concluded in this study. The greatest change is noticed for the sample with the minimum dopant content for a x = 0.05 atomic percent share of yttrium. To reveal the potential role of more than one ion contribution to the overall relaxation process in investigated compounds, a modified Debye's equation was utilized. [ABSTRACT FROM AUTHOR]

The preparation and characterization of six rare earth 2‐methyl‐3‐furoate (2m3fur) complexes are detailed in this study. Analysis through single‐crystal X‐ray diffraction, as well as powder XRD, reveals that all six compounds belong to one of two structural groups: {[RE2(2m3fur)6(EtOH)] ⋅ H2O}n (RE=La, Ce, Pr) and [RE3(2m3fur)9]n (RE=Y, Er, Yb). These structural groups feature carboxylate coordinated linear polymers. The former complexes have two distinct metal centers, one ten coordinate and one nine, with lattice water participating in a hydrogen bond with coordinated ethanol. The latter structures, involving erbium, ytterbium, and yttrium, have three unique metal centers: two eight coordinate, and one seven‐coordinated. In corrosion inhibition tests on mild steel in 0.01 M NaCl solution, the maximum efficiency was observed with [Y3(2m3fur)9]n at 59 %, which is less effective than yttrium 3‐furoate (90 % efficiency). The results suggest that the steric effect of the methyl group adversely affects corrosion inhibition. [ABSTRACT FROM AUTHOR]

The structural properties of photochromic yttrium oxyhydride powder in its transparent state were examined using x-ray diffraction and temperature-dependent extended x-ray absorption fine structure spectroscopy (EXAFS) combined with reverse Monte Carlo (RMC) simulations. The refinement of the x-ray powder diffraction pattern, employing the Rietveld method, indicates that yttrium oxyhydride crystallizes in the nanocrystalline phase with the cubic space group Fm-3m (225), at room temperature. The lattice parameter was determined as a = 5.404(3) Å, and the nanocrystallite size was estimated at d = 16(2) nm. The partial radial distribution functions (RDFs) g(r) for Y–O, O–O, and Y–Y atom pairs were obtained from the results of the RMC simulations of the Y K-edge EXAFS spectra measured at three temperatures (10, 150, and 300 K). The analysis of the RDFs reveals a subtle impact of the thermal disorder and splitting of the second coordination shell of yttrium atoms (the Y–Y RDF), remaining at all temperatures. This observation, also supported by our density functional theory calculations, suggests the presence of local structural distortions associated with yttrium sites, which do not affect the long-range crystal order. [ABSTRACT FROM AUTHOR]

Compounds with the general formula RE3MO7 (RE = rare earth ions; M = Ta, Nb, Sb, Ru, Ir, Os, Re, etc.), crystallize as a fluorite-related structure, forming polymorphs with different space groups. The space group strongly depends on the RE3+ and M5+ ionic radii and processing conditions. Structural characterization is well-established for the lanthanide series, but literature studies have divergent views about how to attribute yttrium tantalate (Y3TaO7) space groups—some authors have described the Y3TaO7 structure as orthorhombic and belonging to space group C2221 or Ccmm, whereas others have assigned a cubic Fm3¯m structure to it. Here, we have characterized the structure of undoped and Eu3+-doped Y3TaO7 (0.1 to 50 mol% of Eu3+) samples synthesized by the sol–gel method that crystallized as a cubic disordered fluorite-type structure, space group Fm3¯m. Their powder X-ray diffraction measurements, Rietveld analyzes and Raman spectra were used as a conclusive technique of the structural properties. We have also investigated whether a secondary phase (M′-YTaO4) emerged in the samples and compared the phase composition of each sample to their Raman spectra. Low-temperature photoluminescence measurements (∼15 K) using Eu3+ as a structural probe helped us analyze the inhomogeneous broadening observed in the emission spectra. These measurements can be used as an important tool to attribute the crystalline phases of rare earth tantalates and niobates. [ABSTRACT FROM AUTHOR]

Oxide-dispersion-strengthened (ODS) steels have long been viewed as a prime solution for harsh environments. However, conventional manufacturing of ODS steels limits the final product geometry, is difficult to scale up to large components, and is expensive due to multiple highly involved, solid-state processing steps required. Additive manufacturing (AM) can directly incorporate dispersion elements (e.g., Y, Ti and O) during component fabrication, thus bypassing the need for an ODS steel supply chain, the scale-up challenges of powder processing routes, the buoyancy challenges associated with casting ODS steels, and the joining issues for net-shape component fabrication. In the AM process, the diffusion of the dispersion elements in the molten steel plays a key role in the precipitation of the oxide particles, thereby influencing the microstructure, thermal stability and high-temperature mechanical properties of the resulting ODS steels. In this work, the atomic diffusivities of Y, Ti, and O in molten 316L stainless steel (SS) as functions of temperature are determined by ab initio molecular dynamics simulations. The latest Vienna Ab initio Simulation Package (VASP) package that incorporates an on-the-fly machine learning force field for accelerated computation is used. At a constant temperature, the time-dependent coordinates of the target atoms in the molten 316L SS were analyzed in the form of mean square displacement in order to obtain diffusivity. The values of the diffusivity at multiple temperatures are then fitted to the Arrhenius form to determine the activation energy and the pre-exponential factor. Given the challenges in experimental measurement of atomic diffusivity at such high temperatures and correspondingly the lack of experimental data, this study provides important physical parameters for future modeling of the oxide precipitation kinetics during AM process. [ABSTRACT FROM AUTHOR]

Asymmetric aminoiminophosphorane Ph2P(NHPbt)(=NMes) (HL) is synthesized by the reaction of Pbt–NHPPh2 and MesN3 (Pbt = 2-(benzothiazol-2-yl)phenyl; Mes = mesityl). Then it is used to obtain [Y(L)Cl2(THF)] complex (1, THF - tetrahydrofuran). The compounds are isolated as crystalline phases: HL, HL·0.5PhMe, 1, and 1·PhMe. They are characterized by single crystal X-ray diffraction, NMR, and IR techniques. A hydrogen bond between the hydrogen atom of the NH group bonded to Pbt and the nitrogen atom of the heterocycle is present in HL. In complex 1, all three nitrogen atoms of the ligand coordinate to the yttrium cation and form a planar structure of chelate rings. The π-stacking is observed between the aromatic moieties of the molecules in both HL and complex 1. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate safety and effectiveness of selective internal radiation therapy (SIRT) using yttrium-90 for localized and locally advanced intrahepatic cholangiocarcinoma (iCCA). Methods: A retrospective review was performed of patients with localized iCCA treated with SIRT at a single institution. Overall survival (OS), local tumor response, progression-free survival (PFS), and toxicity were collected. Stratified analysis was performed based on surgical resection. Predictor analysis of OS was performed using the Fine-Grey regression analysis model with patients bridged to surgery regarded as competing events. Results: A total of 28 consecutive patients with localized iCCA were treated with a total of 38 sessions of SIRT (17 segmental, 13 lobar, and 8 combined deliveries) and a mean dominant target dose per session of 238.4 ± 130.0 Gy. The cumulative radiologic response rate was 16/28 (57.1%) with a median PFS of 265 days. Median survival time (MST) was 22.9 months for the entire cohort with 1-year and 3-year survival of 78.4% and 45.1%, respectively. Ten patients (34.5%) were downstaged to surgical intervention (7 resection, 3 transplant) and showed longer OS (p = 0.027). The 1-year and 3-year OS for patients who received surgery were 100% and 62.5% (95% CI: 14.2–89.3%), respectively. Age (p = 0.028), Eastern Cooperative Oncology Group performance status (p = 0.030), and objective radiologic response (p=0.014) are associated with OS. Two ≥grade 3 hyperbilirubinemia, anemia, and one pleuro-biliary fistula occurred post-SIRT. Conclusions: SIRT for localized iCCA is safe and effective in achieving radiological response, downstaging to surgery and transplant, and resulting in pathologic necrosis. Clinical relevance statement: Selective internal radiation therapy should be considered for patients with localized and locally advanced intrahepatic cholangiocarcinoma. Key Points: • The effectiveness of radioembolization for intrahepatic cholangiocarcinoma (iCCA) can be underestimated given the inclusion of extrahepatic disease. • Radioembolization is safe and effective for local and locally advanced iCCA. Age, Eastern Cooperative Oncology Group performance status, and radiologic response are associated with survival. • Radioembolization should be considered for patients with localized and locally advanced iCCA. [ABSTRACT FROM AUTHOR]

In this research, a nano-sized cobalt ferrite material doped with Yttrium has been successfully fabricated using the sol-gel method of automatic combustion with variations in low sintering temperatures of 200, 300 and 400 °C. The results of refinement of XRD data using the Rietveld method show that the Yttrium-doped cobalt ferrite compound with a Yttrium concentration molarity of 0.1 possess a cubic crystal system and Fd-3m space group. The increasing annealing temperatures also increase the crystallite size of Yttrium-doped cobalt ferrite with the highest magnitude of 16.05 nm. The FTIR results of the samples indicated the presence of Co-O bonds around wave number 385 cm-1 and Fe-O bonds around wave number 582 cm-1 which are characteristic of the presence of cobalt ferrite compounds. From the VSM measurement results, it can be seen that there is a decrease in magnetic saturation with an increase in annealing temperature. The presence of Yttrium substitution, which takes the place of Fe3+ in cobalt ferrite material, indicates lower saturation magnetization. Image from SEM results showed samples have nanoparticle crystallite size. Evaluation of potential photocatalyst applications using a UV-Visible Spectrophotometer (UV-Vis). For Yttrium doped cobalt ferrite at 200 °C, the best degradation efficiency of Congo Red findings showed a magnitude of 76.10 %; the results are confirmed by the occurrence of the smallest crystallite size (15.11 nm). [ABSTRACT FROM AUTHOR]

SiC f /SiC composites have emerged as a prominent research area in the field of structural materials for engine hot-end applications. However, SiC f /SiC composites exhibit susceptibility to oxidation and corrosion when exposed to oxygen and water vapor. The yttrium silicate ceramic in the SiC f /SiC composite (SiC f /SiC-YS composite) serves as corrosion-resistant matrix. The corrosion behavior of SiC f /SiC-YS composites was assessed by examining the phase composition, microstructure, and bending strength after exposure to different water and oxygen environments. The results show that SiC f /SiC-YS composites exhibit excellent resistance to water and oxygen at temperatures below 1300 °C. Above 1300 °C, the decomposition of yttrium disilicate affects the internal structure and bending strength of the composites. Temperature- and water vapor concentration-dependent crystal transformation of yttrium silicate is a crucial factor that influences the microstructure and water-oxygen corrosion resistance of SiC f /SiC-YS composites. [ABSTRACT FROM AUTHOR]

• W3 alloy was successfully consolidated by SLM and SPS almost without porosity. • Microstructure is significantly affected by the processing method. • Mechanical strength is comparable to the extruded material. • Deformability is primarily affected by porosity, grain structure and residual strain. • SPS material showed convenient combination of mechanical and degradation properties. This work explored possibilities of biodegradable magnesium alloy Mg-3Y preparation by two modern powder metallurgy techniques – spark plasma sintering (SPS) and selective laser melting (SLM). The powder material was consolidated by both methods utilising optimised parameters, which led to very low porosity (∼0.3%) in the SLM material and unmeasurably low porosity in the SPS material. The main aim of the study was the thorough microstructure characterisation and interrelation between the microstructure and the functional properties, such as mechanical strength, deformability, and corrosion resistance. Both materials showed comparable strength of ∼110 MPa in tension and compression and relatively good deformability of ∼9% and ∼21% for the SLM and SPS materials, respectively. The corrosion resistance of the SPS material in 0.1 M NaCl solution was superior to the SLM one and comparable to the conventional extruded material. The digital image correlation during loading and the cross-section analysis of the corrosion layers revealed that the residual porosity and large strained grains have the dominant negative effect on the functional properties of the SLM material. On the other hand, one of the primary outcomes of this study is that the SPS consolidation method is very effective in the preparation of the W3 biodegradable alloy, resulting in material with convenient mechanical and degradation properties that might find practical applications. [ABSTRACT FROM AUTHOR]

The luminescence properties of erbium and yttrium co‐doped cadmium difluoride with three different concentrations of yttrium were investigated. First, we synthesized single crystal samples with good optical quality using the Bridgman technique. From the optical absorption spectra, recorded at room temperature, both in the ultraviolet–visible and infrared spectral ranges, Judd–Ofelt analysis was performed based on yttrium concentrations to predict the radiative properties of Er3+ luminescent ions. For the 10% optimum concentration of yttrium, a detailed photoluminescence investigation was carried out. We mainly explored green, red, and near‐infrared fluorescence under different excitation wavelengths and presented their highlight spectroscopic characteristics. The desired transitions had relatively high emission cross‐sections both under visible and near‐infrared excitation. Optical gain followed a similar trend. Furthermore, the dynamic fluorescence study showed a significant increase in the measured lifetime under an 800 nm infrared excitation. The upconversion process under an 800 nm excitation produced quantum efficiency greater than 100% due to the contribution of more than one energy transfer mechanism. [ABSTRACT FROM AUTHOR]

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Wear-resistant sealing coatings of KNA-82 system with 0.1% yttrium addition for hot parts of gas-turbine engines, applied by gas-flame and ion-plasma methods, are considered. The introduction of yttrium increases the operating temperature from 900°C to 1100°C. The methodology of modeling of processes of contact interaction of engine parts under operating conditions has been developed. Tribotechnical tests modeling the contact of the coating surface with the rotor ridge tops and blade feathers have been carried out, after which linear wear has been measured and the results have been statistically processed. The gas-flame coatings show slower wear reduction at temperatures up to 800°C, while both coatings show similar properties at 1100°C. The improved properties are attributed to the formation of phase-like Ni3Y compound in the grain boundaries.

We have systematically investigated the solution and aggregation behaviors of yttrium (Y) on symmetrically inclined tungsten (W) grain boundary (GB) Σ 5 (310)/[001] by first-principles simulation. It is found that the most stable site for Y is located on the GB plane, and the solution energy of the Y substitutional site increases with increasing the distance from the GB plane. The charge redistribution of Y atoms is positively correlated with the solution energy, i.e., the deviation of the electrons of Y atoms is beneficial to its solution in the W–GB system. Further, the segregation of multiple Y atoms in the W–GB is clearly observed, where the Y atoms preferentially occupy the GB plane substitutional sites. The alloying Y atoms at the GB plane sites can effectively strengthen the GB when the concentration is less than 3.367%. The stronger binding energy of W–Y than the binding energy of W–W in the GB region is the main factor for the strengthening of the GB. [ABSTRACT FROM AUTHOR]

The effect of yttrium on the 475 °C brittleness and microstructure stability of Fe–13Cr–6Al–2Mo-0.5Nb-0.15Zr alloy after long-term aging at 475 °C has been investigated. At the early stage of aging, the nanoscale metastable transition phase precipitates in large quantities. After aging for 10,000 h, the nanophase in the Y-free alloy has completely disappeared, and only a great deal of granular Laves phases are left, while a large number of nanoscale phases still exist in the grain of Y-containing alloys. This is because the addition of yttrium combines with vacancies, hinders the diffusion of Laves phase-forming elements, and has the result that the transformation of nanoscale phases Fe2(Mo0.3Nb0.7)Al to Laves phase is inhibited during the aging process of the Y-containing alloys. During aging, precipitation-free zones (PFZ) are formed in the surrounding area where the Laves phase and grain boundaries exist. The elongation of Y-containing alloys decreases with yttrium content, but it is still higher than that of Y-free alloy. The addition of yttrium improves the aging plasticity and weakens the degree of 475 °C brittleness of the alloy, and the effectiveness is diminished with the yttrium. This plays a key role in the further study of Fe–Cr–Al alloys for fuel cladding materials.

Mg97Zn1Y2 alloys with high ignition temperatures were developed by adding Sr. The addition of Sr resulted in the formation of a uniform and thin Y2O3 film. Mg–Zn–Y alloys containing at least 0.25 at.% Sr exhibited ignition temperatures of 1270–1320 K. As a result of EDS measurement, Sr was found to be concentrated in the Y2O3 film. In addition, a mixed film of MgO and SrO formed on the outer layer in the 1.5 at.% Sr-containing Mg97Zn1Y2 alloy. These findings suggest that the uniform and thin Y2O3 film that maintains high soundness at high temperatures was formed owing to valence control and the formation of a protective outer oxide film.

The search for new superhydrides, promising materials for both hydrogen storage and high temperature superconductivity, made great progress, thanks to atomistic simulations and Crystal Structure Prediction (CSP) algorithms. When they are combined with Density Functional Theory (DFT), these methods are highly reliable and often match a great part of the experimental results. However, systems of increasing complexity (number of atoms and chemical species) become rapidly challenging as the number of minima to explore grows exponentially with the number of degrees of freedom in the simulation cell. An efficient sampling strategy preserving a sustainable computational cost then remains to be found. We propose such a strategy based on an active-learning process where machine learning potentials and DFT simulations are jointly used, opening the way to the discovery of complex structures. As a proof of concept, this method is applied to the exploration of tin crystal structures under various pressures. We showed that the α phase, not included in the learning process, is correctly retrieved, despite its singular nature of bonding. Moreover, all the expected phases are correctly predicted under pressure (20 and 100 GPa), suggesting the high transferability of our approach. The method has then been applied to the search of yttrium superhydrides (YHx) crystal structures under pressure. The YH6 structure of space group Im-3m is successfully retrieved. However, the exploration of more complex systems leads to the appearance of a large number of structures. The selection of the relevant ones to be included in the active learning process is performed through the analysis of atomic environments and the clustering algorithm. Finally, a metric involving a distance based on x-ray spectra is introduced, which guides the structural search toward experimentally relevant structures. The global process (active-learning and new selection methods) is finally considered to explore more complex and unknown YHx phases, unreachable by former CSP algorithms. New complex phases are found, demonstrating the ability of our approach to push back the exponential wall of complexity related to CSP. [ABSTRACT FROM AUTHOR]

We show here that yttrium is immiscible and precipitates with various sizes in the body centered cubic V 0.6 Ti 0.4 alloy superconductor. The number and size of the precipitates are found to depend on the amount of yttrium added. Precipitates with various sizes up to 30 μ m are found in the V 0.6 Ti 0.4 alloy containing 5 at. % yttrium. The large amount of line disorders generated by the addition of yttrium in this alloy is found to be effective in pinning the magnetic flux lines. While the superconducting transition temperature increases with the increasing amount of yttrium in the V 0.6 Ti 0.4 alloy, the critical current density is maximum for the alloy containing 2 at. % yttrium, where it is more than 7.5 times the parent alloy in fields higher than 1 T. We found that the effectiveness of each type of defect in pinning the flux lines is dependent on the temperature and the applied magnetic filed. [ABSTRACT FROM AUTHOR]

The yttrium-hydrogen system has gained attention because of near-ambient temperature superconductivity reports in yttrium hydrides at high pressures. We conducted a study using synchrotron single-crystal x-ray diffraction (SCXRD) at 87 to 171 GPa, resulting in the discovery of known (two YH3 phases) and five previously unknown yttrium hydrides. These were synthesized in diamond anvil cells by laser heating yttrium with hydrogen-rich precursors--ammonia borane or paraffin oil. The arrangements of yttrium atoms in the crystal structures of new phases were determined on the basis of SCXRD, and the hydrogen content estimations based on empirical relations and ab initio calculations revealed the following compounds: Y3H11, Y2H9, Y4H23, Y13H75, and Y4H25. The study also uncovered a carbide (YC2) and two yttrium allotropes. Complex phase diversity, variable hydrogen content in yttrium hydrides, and their metallic nature, as revealed by ab initio calculations, underline the challenges in identifying superconducting phases and understanding electronic transitions in high-pressure synthesized materials. [ABSTRACT FROM AUTHOR]

The commercialization of ternary layered cathode materials with a relative nickel content of more than 90 % faces serious challenges. Among them, it is urgent to address the issues of rapid capacity degradation and structural degradation. Herein, we provide a simple process for doping yttrium at the precursor preparation stage. The feasibility of yttrium doping in the precursor and the positive effects of yttrium ions on the crystal structure and properties of the cathode materials are scientifically explained by a variety of characterization and testing methods, such as Eh-pH, Particle Size Analyzer, ICP, SEM, EDS, XRD, XPS, HRTEM, dQ/dV, CV, EIS and DFT. Yttrium-doped NCMY cathode materials have more stable lattice oxygen and significantly less irreversible phase transition. Furthermore, the electrochemical performance of the NCMY cathode material is significantly improved, with a capacity retention rate of 82.71 % after 150 cycles at a current density of 1C, which is much higher than 65.39 % for NCM. The NCMY cathode material significantly improves the lithium ion diffusion ability, especially at the high rate of 10C, the discharge specific capacity is still as high as 177.05 mAh g−1. [ABSTRACT FROM AUTHOR]

In the modern world, rare earth elements (REE) and yttrium (Y) dominate the development of high-end electronic equipment and green energy technologies. The global economic deposits of REE and Y are primarily associated with alkaline and peralkaline igneous rocks. The REE deposit of the Siwana ring complex, Rajasthan, India, is entirely composed of peralkaline igneous rocks. This complex is made up of REE and Y-enriched (both LREE and HREE) peralkaline granite, rhyolite and its younger felsic intrusives such as rhyolite, microgranite, aplite and felsite dykes. We present a study of the REE and Y potential of granites, volcanic rocks and felsic dykes from 17 quarries in the Siwana area. Monazite, zircon and apatite were the primary (magmatic) REE-bearing phases identified under a microscope. The late/post-magmatic replacement in granite is evident as coarsening of perthite lamellae, pseudomorphic replacement of alkali feldspar grains by aegirine, replacement of aenigmatite by aegirine, etc. The granites, volcanic rocks and dykes show significant enrichment of REE + Y and other trace elements (Sn, Hf and U). A total of 20 rock samples were analysed using inductively coupled plasma mass spectrometry, which indicated significant REE + Y values ranging between 1061.22 and 9088.62 ppm, with an average of 2361.89 ppm. This includes LREE (707.42-5743.83 ppm, avg. 2080.40 ppm) and HREE (135.77-1422.23 ppm, avg. 402.41 ppm) Hf up to 425.55 ppm. Totally five samples from a soil profile were also analysed, yielding REE + Y values between 223.39 and 3175.75 ppm, with an average of 1714.51 ppm. The ion adsorption clay horizon developed within the soil profile showed a maximum REE + Y value of 3175.75 ppm. [ABSTRACT FROM AUTHOR]

In this work, tensile samples of a Yttrium-alloyed nickel-base superalloy 718 were eletrochemically charged with hydrogen and compared with reference samples with no Y addition. It was shown that Y promoted an increase in the ductility of the material for both the hydrogenated and the reference samples, especially for the homogeneous deformation. This effect was attributed to the refinement of the microstructural features and the control of deleterious elements like sulphur and oxygen, mitigating the embrittling effect of hydrogen. Furthermore, the Y-alloying hampered the H ingress into the material and increased the critical concentration needed for fracture along the grain boundaries. [Display omitted] • Y-alloying increased the overall ductility of the alloy. • Loss of ductility due to H was lower for the Y-alloyed samples. • Y can provide more H trapping and lower the H ingress. • Y lowers the content of harmful elements and increases grain boundary cohesion. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Monitoring of sweat pH plays important roles in physiological health, nutritional balance, psychological stress, and sports performance. However, the combination of functional MOFs with phosphorescent material to acquire the real‐time physiological information, as well as the application of dual mode anti‐counterfeiting, has seldom been reported. Herein, we developed multifunctional gel films based on MOFs and phosphorescent dyes which responded to H+ ions and the related mechanism was studied in detail. Upon exposure to H+, the composite gel film exhibited decreased fluorescent signal but enhanced room temperature phosphorescence (RTP), which could be utilized for sweat pH sensing through a dual‐mode. Moreover, multifunctional gel films exhibited a potential application in information encryption and anti‐counterfeiting by designing of stimulus responsive multiple patterns. This research provided a new avenue for portable and non‐invasive sweat pH monitoring methods while also offering insights into stimulus‐responsive multifunctional materials. [ABSTRACT FROM AUTHOR]

The effect of alloying with manganese and titanium on phase composition and mechanical properties of new Al-Zn-Mg-Cu-Zr-Y(Er) alloys is studied using thermodynamic calculations, scanning electron microscopy, and X-ray phase analysis. Introduction of manganese into AlZnMgCuZrY and AlZnMgCuZrEr alloys leads to formation of (Al,Cu)11Y3, Al25Cu4Mn2Y, and Al25Cu4Mn2Er phases respectively, in which up to 12 wt.% Zn is dissolved, which replaces aluminum atoms within the phase lattice. In the process of homogenization for phases enriched in yttrium or erbium hardly change their morphology, while T(Al,Zn,Mg,Cu) phase dissolves and transforms into the S(Al2CuMg) phase. In this case, according to calculations, Al6Mn, Al3Zr, and Al3Ti phases are present in equilibrium with (Al). Microstructural studies confirm presence of particles within aluminum solid solution (Al), i.e. heterogenization proceeds in parallel with homogenization. The course of heterogenization provides 7–15 HV greater hardness for alloys with manganese in a quenched condition, but they have a less alloyed solid solution in terms of Zn, Mg, and Cu, which reduces hardening during aging. Alloys doped with manganese and titanium are hardly inferior in terms of yield strength, and when temperature rises to 300–350 °C, they slightly surpass alloys without them. Modification with titanium leads to grain refinement, which contributes to yield strength, partly compensating for the lower alloying (Al). [ABSTRACT FROM AUTHOR]

Oxynitrides such as LaTa(O,N)3 are attractive materials as photoelectrodes for photoelectrocatalytic solar water splitting. The potential anionic ordering in their perovskite-type structure has been shown to impact the materials' properties. Given the importance attributed to it, the present study reports a detailed experimental analysis supported by simulations of the anionic ordering of La1−xYxTa(O,N)3. The influence of O/N and yttrium content on the anionic order was assessed. Neutron diffraction analysis was performed on four different nominal compositions—LaTaON2, LaTaO2N, La0.9Y0.1TaON2, and La0.9Y0.1TaO2N—at 10 K and 300 K to study potential long-range ordering. Neutron pair distribution function (PDF) analysis was performed on all samples at 10 K and on non-Y-substituted samples at 300 K to evaluate short-range ordering. There was no evidence of long-range O/N order in any of the compounds. In contrast, at a short range (1.5 Å ≤ r < 6 Å), a Pnma (a−b+a−) tilting pattern and local cis-ordering of the anions were seen. The latter faded rapidly, leaving the Pnma tilting pattern in a 6 Å ≤ r ≤ 11 Å range. At higher distances, the PDF analysis agreed with the Imma (a−b0a−) O/N disordered long-range structure. As the O/N content changed, not much difference in behavior was observed. Yttrium substitution introduced some disorder in the structure; nonetheless, it showed marginal influence on octahedral tilting and anionic ordering. [ABSTRACT FROM AUTHOR]

There are many great uses for heavy elements that are expanding daily and generating enormous amounts of effluents. Therefore, tremendous scientific efforts in removing, recovering, and recycling them are carried out to prevent these harmful effects on the environment and human health. The polyacrylic-carboxymethyl cellulose-trioctyl amine/reduced graphene oxide adsorbent (AA-CMC-TOA/rGO) was synthesized as a promising sorbent for Zr4+ and Y3+ ions by gamma irradiation for a mixture of acrylic acid, carboxymethyl cellulose, and trioctyl amine as an organic solvent. A complete characterization of the manufactured composite was carried out to find out its chemical and physical properties several techniques such as XRD, EDX, SEM, FT-IR, TGA-DTA, and BET. Several factors affecting the Zr4+ and Y3+ adsorption processes were studied to set the best conditions that achieve the extreme loading capacity of Zr4+ and Y3+ ions. Loading capacities of 0.99 and 1.07 mmol g−1 were achieved for Zr4+ and Y3+, respectively. The results of the kinetic models indicated that the adsorption reactions of Zr4+ and Y3+ ions were carried out via a chemical reaction mechanism. Langmuir, Dubinin–Radushkevich, and Redlich–Peterson models accurately described the adsorption isotherm data by proving their chemical nature. The results of thermodynamics added evidence of the chemical nature, spontaneous, and endothermic nature of the adsorption processes. A complete retrieval for Zr4+ and Y3+ ions contents located in the effluent was efficiently achieved using AA-CMC-TOA/rGO sorbent which proved its uses as a promising sorbent. [ABSTRACT FROM AUTHOR]

Diamidophosphine tBuP(NHMes)2(H2L) is synthesized by the treatment of tBuPCl2 with two equivalents of KNHMes (Mes is 2,4,6-Me3C6H2). The reaction of H2L with potassium hydride in THF (THF is tetrahydrofuran) affords the anionic form HL− with the hydrogen atom migrating from nitrogen to phosphorus, which is confirmed by the 1H and 31P NMR data. The structure of the formed iminophosphonamidinate anion HL− is determined by X-ray diffraction (XRD) in the crystalline phase of K[K(THF)2](tBuPH(NMes)2)2∙C7H8 (KHL). The reaction of KHL with yttrium chloride gives complex [Y(tBuPH(NMes)2)2Cl] ([Y(HL)2Cl]) in which, according to the XRD data, ligands HL− are in the iminophosphonamidinate PH form. The 1H and 31P NMR spectra confirm that this structure of the complex exists in the solution. [ABSTRACT FROM AUTHOR]