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Neodymium (Nd) magnets (Nd 2 Fe 14 B) are key materials for achieving high energy conversion efficiency. The coercive forces (fields) of the magnets are often reinforced by adding dysprosium (Dy), especially at high temperatures. To understand the magnetic properties of Dy-substituted systems (Nd 1 − x Dy x) 2 Fe 14 B, it is important to study those of Dy 2 Fe 14 B and Nd 2 Fe 14 B and analyze the difference in detail from a microscopic viewpoint. Applying a recently developed atomistic model approach, we investigated thermodynamic properties of these magnets. We studied the temperature and field dependences of the magnetizations, and anisotropy fields and energies. We found that the simulation results captured the characteristic features of the experimentally observed data. We discuss the detail with the magnetization profiles of the component atoms. Furthermore, we investigated the effect of Dy random substitution on the coercivity in two systems: one in contact with vacuum and the other in contact with a grain boundary phase. We found that the threshold fields increased almost linearly with the concentration of Dy atoms in both systems, which was compared to the results of the layer-by-layer substitution effect analyzed in our previous work. We discuss the influence of the arrangement of Dy atoms on coercivity enhancement. [ABSTRACT FROM AUTHOR]

In this work, the Dy 2 O 3 -Al 2 O 3 -SiO 2 (DASN) and Dy 2 O 3 -Al 2 O 3 -SiO 2 -TiO 2 (DAST) glass fillers were used for joining alumina ceramic. During the cooling process of the alumina/DASN/alumina joints, Dy 2 Si 2 O 7 and Al 2 O 3 were precipitated simultaneously and gradually grown. As a result, voids were formed due to the poor flowability of the glass ceramic filler and the large density difference between the glass filler and Dy 2 Si 2 O 7 crystals. On the contrary, the addition of TiO 2 altered the sequence of the crystalline phase precipitation during the cooling process. During cooling from the joining temperature (1450 °C) to 1100 °C, only Dy 2 Si 2 O 7 was formed in the brazing seam. Simultaneously, the flowing glass phase was able to fill the spaces caused by the density differences. When the growth of Dy 2 Si 2 O 7 phase ceased, the Al 2 O 3 phase began to precipitate. Therefore, the voids caused by density differences can be eliminated in the alumina/DAST/alumina joints with high crystallinity. The optimal flexural strength of alumina/DAST/alumina joints tested at room temperature and 1000 °C reached 350 MPa and 158 MPa, respectively. [ABSTRACT FROM AUTHOR]

[Dy (LMe)(H2O)]CF3SO3·0.25H2O (1·0.25H2O), where H2LMe is the reported ligand 2,2′‐(((pyridine‐2,6‐diylbis (methylene))bis((pyridin‐2‐ylmethyl)azanediyl))bis (methylene))bis(4‐methylphenol), shows the DyIII ion in an N5O3 environment, with triangular dodecahedral geometry (D2d symmetry). 1·0.25H2O is a single ion magnet (SIM) with an energy barrier for spin reversal of 510 K, and open hysteresis loops up to 8 K. The magnetostructural comparison of 1·0.25H2O with some closely related complexes and with other eight‐coordinated SIMs with high energy barriers (> 300 K) allows to draw some conclusions to enhance the magnetic performance in these nanomagnets with non‐purely axial geometries. Ab initio calculations complement and support the experimental results. [ABSTRACT FROM AUTHOR]

Objective Methods Results Conclusion To evaluate the levels of serum rare earth elements (REEs): lutetium [Lu], praseodymium [Pr], samarium [Sm], dysprosium [Dy], and cerium [Ce] in pregnant women with recurrent pregnancy loss (RPL) and evaluate their relationship with total antioxidant capacity (TAC) and 8‐hydroxy‐2′‐deoxyguanosine (8‐OHdG), a marker of DNA damage.A case‐controlled study was conducted on a cohort of 60 female participants, with first‐trimester healthy pregnant women as the control group and pregnant women with a history of consecutive abortions as the recurrent pregnancy loss (RPL) group. Following blood collection, serum concentrations of Lu, Pr, Sm, Dy, and Ce were measured using an inductively coupled plasma mass spectrophotometer (ICP‐MS). Oxidative stress and DNA damage were evaluated through TAC and DNA damage marker (8‐OHdG).Serum levels of Lu, Pr, Sm, Dy, and Ce were higher in women with RPL compared with control (P < 0.001). Intriguingly, a strong significant negative correlation was observed between TAC and REEs (P < 0.05). Lu, Dy, and Ce demonstrated a significant positive correlation with increased DNA damage in the RPL group (P < 0.05). Contrary, there was no evidence of a correlation between 8‐OHdG and Pr and Sm.The study highlights a potential association between Lu, Sm, Dy, and Ce and an increased risk of RPL, highlighting REE‐induced toxicity as a major risk factor for RPL. The outcome of the study is to advance our understanding of the interplay between rare earth elements and RPL, with potential implications for reproductive medicine, environmental health, and the development of preventive strategies for individuals at risk of RPL. [ABSTRACT FROM AUTHOR]

Conventionally, octahedral (Oh) coordination symmetry of lanthanide centers is not ideal for constructing high-performance single-molecule magnets (SMMs). However, introducing a strong ligand field in the axial direction to increase crystal field splitting can potentially overcome this limitation. Herein, we successfully obtained two dysprosium(III) single-molecule magnets, [Dy(OCtBu3)X2(py)3] (X = Cl (1), I (2), py = pyridine), in Oh coordination symmetry. The two complexes differ only in the coordinating anions on the equatorial plane, yet their magnetic performances are distinctly different. When chloride is replaced by a weaker donor iodide, the energy barrier is dramatically improved from 29 cm−1 (1) to 860 cm−1 (2), highlighting the importance of weakening the transverse ligand field and maximizing the axial ligand field for high-performance SMMs. [ABSTRACT FROM AUTHOR]

Lead borate glass is the best radiation shielding glass when lead is in high concentration. However, it has low transparency after radiation exposure. Radiation decreases transparency due to chemical and physical changes in the glass matrix, such as creating or healing defects in the glass network. The addition of rare earth elements like cerium and dysprosium oxides to lead borate glasses can improve their transparency and durability as radiation shielding barriers. The newly manufactured glasses' optical absorption, structural, and radiation shielding properties were measured. The optical characteristics of the generated samples were examined to determine the effect of the cerium/dysprosium ratio on the structural alterations, specifically in the presence of bridging oxygen (BO) and non-bridging oxygen (NBO). Incorporating Ce3+ results in peaks at 195 nm for borate units, 225 nm for Ce3+, and a broadened peak at 393 nm due to overlapping peaks for Ce3+ and Ce4+ in the UV region. By adding Dy, multiple peaks are observed at 825, 902, 1095, 1275, and 1684 nm, corresponding to the transition from 6H15/2 ground state to 6F5/2, 6F7/2, 6F9/2, 6F11/2, and 6H11/2. The samples were also tested before and after exposure to gamma irradiation from a 60Co source at a dose of 75 kGy to assess their stability against radiation. The energy gap value during irradiation shows decreased non-bridging oxygen. The energy gap difference before and after irradiation for the M4 sample shows higher NBO to BO conversion, reducing radiation damage and improving structural stability. Furthermore, X-ray photoelectron spectroscopy was utilized to get insight into the coordination chemistry of the created glass samples. The half-value layer (HVL), radiation protection efficiency (RPE), neutron removal cross-section (FRNCS), mean free path (MFP), mass attenuation coefficients (MAC), and effective atomic numbers (Zef) of the glassy structure were calculated theoretically to assess its radiation shielding qualities. The linear attenuation coefficient order for the prepared samples was M1 > M2 > M3 > M4. The FRNCS values were 0.090, 0.083, 0.081, and 0.079 cm−1 for samples M1, M2, M3, and M4, respectively. [ABSTRACT FROM AUTHOR]

The rare earth elements (REEs) are critical resources for many clean energy technologies, but are difficult to obtain in their elementally pure forms because of their nearly identical chemical properties. Here, an analogue of macropa, G‐macropa, was synthesized and employed for an aqueous precipitation‐based separation of Nd3+ and Dy3+. G‐macropa maintains the same thermodynamic preference for the large REEs as macropa, but shows smaller thermodynamic stability constants. Molecular dynamics studies demonstrate that the binding affinity differences of these chelators for Nd3+ and Dy3+ is a consequence of the presence or absence of an inner‐sphere water molecule, which alters the donor strength of the macrocyclic ethers. Leveraging the small REE affinity of G‐macropa, we demonstrate that within aqueous solutions of Nd3+, Dy3+, and G‐macropa, the addition of HCO3− selectively precipitates Dy2(CO3)3, leaving the Nd3+−G‐macropa complex in solution. With this method, remarkably high separation factors of 841 and 741 are achieved for 50 : 50 and 75 : 25 mixtures. Further studies involving Nd3+:Dy3+ ratios of 95 : 5 in authentic magnet waste also afford an efficient separation as well. Lastly, G‐macropa is recovered via crystallization with HCl and used for subsequent extractions, demonstrating its good recyclability. [ABSTRACT FROM AUTHOR]

This article provides information on the synthesis and properties of polylactic acid (PLA), a biodegradable plastic made from renewable resources. It discusses the use of tin(II) chloride for PLA synthesis and the addition of additives to alter its properties. The article also explores the environmental impact and sustainability of bioplastics, highlighting the need for comprehensive life cycle assessments and improved recycling infrastructure. It suggests that a focus on energy aspects and global recycling may be more promising than solely relying on bioplastics. [Extracted from the article]

Single-molecule magnets (SMMs) are a kind of nanosized magnetic materials that are capable of storing massive bytes of information. Strongly coupling the spin centers in a proper manner is a usual approach to promote the working temperature (or blocking temperature) for SMMs. Electron delocalized radicals have been widely employed to accomplish this job. Here, we show a new manner by using weak but multiple B–Hδ− ⋯ Dy3+ inverse hydrogen bonding (IHB) interactions to control the magnetic couplings in a series of dimeric dysprosiacaborane SMMs. This approach leads to a record high TB100s of 10 K among non-radical bridged dimeric SMMs, which is mainly ascribed to strong ferromagnetic coupling (4.38 cm−1) and the proper alignment of the magnetic principle axes of the adjacent dysprosium(III) ions. In verifying by theoretical calculations, these results demonstrate that IHB interactions can be used to construct strong axial ferromagnetic coupling and enhancing magnetic blocking temperature for SMMs. [ABSTRACT FROM AUTHOR]

Deep eutectic solvents (DESs) composed of a beta-diketone and phosphine oxides featuring different alkyl chain lengths were prepared and then employed as liquid-liquid extraction and dissolution media for the separation of iron, cobalt, neodymium, and dysprosium. In the dissolution the more sterically hindered DESs exhibited enhanced selectivity to neodymium, which was poorly separated using liquid-liquid extraction. The dissolution selectivity in less sterically hindered DESs could be controlled by the addition of organic acids with different alkyl chain lengths. [ABSTRACT FROM AUTHOR]

A Dy(III) coordination polymer (CP), [Dy(spasds)(H2O)2]n (1) (Na2Hspasds = 5-(4-sulfophenylazo)salicylic disodium salt), has been synthesized using a hydrothermal method and characterized. 1 features a 2D layered structure, where the spasda3− anions act as pentadentate ligands, adopting carboxylate, sulfonate and phenolate groups to bridge with four Dy centers in η3-μ1: μ2, η2-μ1: μ1, and monodentate coordination modes, respectively. It possesses a unique (4,4)-connected net with a Schläfli symbol of {44·62}{4}2. The luminescence study revealed that 1 exhibited a broad fluorescent emission band at 392 nm. Moreover, the visual blue color has been confirmed by the CIE plot. 1 can serve as a dual-functional luminescent sensor toward Fe3+ and MnO4− through the luminescence quenching effect, with limits of detection (LODs) of 9.30 × 10−7 and 1.19 × 10−6 M, respectively. The LODs are relatively low in comparison with those of the reported CP-based sensors for Fe3+ and MnO4−. In addition, 1 also has high selectivity and remarkable anti-interference ability, as well as good recyclability for at least five cycles. Furthermore, the potential application of the sensor for the detection of Fe3+ and MnO4− was studied through simulated wastewater samples with different concentrations. The possible sensing mechanisms were investigated using Ultraviolet-Visible (UV-Vis) absorption spectroscopy and density functional theory (DFT) calculations. The results revealed that the luminescence turn-off effects toward Fe3+ and MnO4− were caused by competitive absorption and photoinduced electron transfer (PET), and competitive absorption and inner filter effect (IFE), respectively. [ABSTRACT FROM AUTHOR]

Quantum many-body scars are notable as nonthermal, low-entanglement states that exist at high energies. In this study, we used attractively interacting dysprosium gases to create scar states that are stable enough to be driven into a strongly nonlinear regime while retaining their character. We measured how the kinetic and total energies evolve after quenching the confining potential. Although the bare interactions are attractive, the atoms behave as if they repel each other: Their kinetic energy paradoxically decreases as the gas is compressed. The missing “phantom” energy is quantified by benchmarking our experimental results against generalized hydrodynamics calculations. We present evidence that the missing kinetic energy is carried by undetected, very high momentum atoms. [ABSTRACT FROM AUTHOR]

The rapid reduction of fossil fuels due to excessive consumption has prompted the development of sustainable energy conversion systems, leading to an increasing energy crisis and environmental concerns. The continuous energy demand motivates researchers to explore new options for energy conversion and water splitting. But, the fabrication of electrocatalysts with low overpotential for water splitting is challenging task. Current study reports the fabrication of rGO-based Dy 2 O 3 composite as an electrocatalyst for water splitting. The rGO-based Dy 2 O 3 was fabricated via a hydrothermal approach. The various physical methods were performed to assess the morphological, vibrational, structural, functional and textual characteristics of synthesized electrocatalysts. In addition, the electrochemical potential of generated materials is evaluated in 1 M KOH electrolyte using Ni foam (NF) serving as conductive material. The electrochemical findings show that rGO-based Dy 2 O 3 composite exhibits a least overpotential of 251 mV at current density (C d) of 10 mA cm−2 and possessing Tafel slope (36 mV dec−1). The Dy 2 O 3 /rGO composite demonstrates stability over a period of 50 h with a minute change in current. The Dy 2 O 3 /rGO composite stands out as a favorable catalyst for OER and future energy conversion applications due to its remarkable electrochemical characteristics. [ABSTRACT FROM AUTHOR]

In this research study, various nanocomposites, namely Dy 2 O 3 , Sm 2 O 3 , HAP/Dy 2 O 3 , HAP/Dy 2 O 3 /GO, and HAP/Sm 2 O 3 /GO, were extensively examined and analyzed. The primary focus was on the development of advanced biomaterials with improved mechanical properties, biocompatibility, and antimicrobial activity. The investigation involved the use of transmission electron microscopy (TEM) and scanning electron microscopy (SEM) techniques to observe the distinctive nanorods of hydroxyapatite (HAP) within the ternary nanocomposite. The SEM micrographs yielded an average size of 69 ± 22 * 19 ± 4 nm for the HAP nanorods, accompanied by an average roughness measurement of 10.5 nm. The TEM analysis provided further insights into the distribution of HAP and Sm 2 O 3 within graphene oxide (GO) nanosheets, revealing HAP particles measuring 20 nm in size and 65 nm in length, and Sm 2 O 3 particles measuring 6 nm in size. To evaluate the biocompatibility of the newly developed ternary nanocomposite, HAP/Dy 2 O 3 /GO, osteoblast cells were employed. The results showed a minor decrease in cell viability, with a measured percentage of cell viability at 97.5 ± 2.1 %. Furthermore, the HAP/Dy 2 O 3 /GO nanocomposite exhibited notable antibacterial properties against E. coli and S. aureus bacteria, as indicated by inhibition zones measuring 15.3 ± 0.8 mm and 15.9 ± 1.1 mm, respectively. The unique composition of HAP/Dy 2 O 3 /GO demonstrated enhanced roughness parameters and improved biocompatibility due to its altered topological features. Additionally, its remarkable antibacterial activity and robust mechanical strength establish HAP/Dy 2 O 3 /GO as a promising candidate for further investigation as a biomaterial for bone implants. [ABSTRACT FROM AUTHOR]

Abstract Lead borate glass is the best radiation shielding glass when lead is in high concentration. However, it has low transparency after radiation exposure. Radiation decreases transparency due to chemical and physical changes in the glass matrix, such as creating or healing defects in the glass network. The addition of rare earth elements like cerium and dysprosium oxides to lead borate glasses can improve their transparency and durability as radiation shielding barriers. The newly manufactured glasses’ optical absorption, structural, and radiation shielding properties were measured. The optical characteristics of the generated samples were examined to determine the effect of the cerium/dysprosium ratio on the structural alterations, specifically in the presence of bridging oxygen (BO) and non-bridging oxygen (NBO). Incorporating Ce3+ results in peaks at 195 nm for borate units, 225 nm for Ce3+, and a broadened peak at 393 nm due to overlapping peaks for Ce3+ and Ce4+ in the UV region. By adding Dy, multiple peaks are observed at 825, 902, 1095, 1275, and 1684 nm, corresponding to the transition from 6H15/2 ground state to 6F5/2, 6F7/2, 6F9/2, 6F11/2, and 6H11/2. The samples were also tested before and after exposure to gamma irradiation from a 60Co source at a dose of 75 kGy to assess their stability against radiation. The energy gap value during irradiation shows decreased non-bridging oxygen. The energy gap difference before and after irradiation for the M4 sample shows higher NBO to BO conversion, reducing radiation damage and improving structural stability. Furthermore, X-ray photoelectron spectroscopy was utilized to get insight into the coordination chemistry of the created glass samples. The half-value layer (HVL), radiation protection efficiency (RPE), neutron removal cross-section (FRNCS), mean free path (MFP), mass attenuation coefficients (MAC), and effective atomic numbers (Zef) of the glassy structure were calculated theoretically to assess its radiation shielding qualities. The linear attenuation coefficient order for the prepared samples was M1 > M2 > M3 > M4. The FRNCS values were 0.090, 0.083, 0.081, and 0.079 cm−1 for samples M1, M2, M3, and M4, respectively.

In this work, the structural and optical characteristics of silicon (n-Si) samples and its compositions with dysprosium (n-Si-Dy) were analyzed using Fourier transform infrared spectroscopy (FTIR) and Raman spectroscopy methods. Characteristic peaks in the FTIR spectra such as 640 cm-1 (Si-H mode) and 1615 cm-1 (perpendicular stretching mode) were identified, indicating the structural features of the material. The appearance of additional peaks in the n-Si-Dy spectra at 516.71 cm-1 and 805 cm-1 indicates the influence of dysprosium on the structure and defectiveness of the material. Examination of the frequency range (1950–2250 cm-1) further confirms local vibration modes associated with defects and interactions with dysprosium. Peaks associated with Dy-Dy stretching, as well as interaction with silicon, were found at 2110 cm-1 and 2124 cm-1. Analysis of Raman spectra indicates the formation of silicon nanocrystals during annealing, which is confirmed by XRD results. The results obtained provide important insight into the effect of dysprosium on the structure and properties of silicon materials, which could potentially find application in optoelectronics and materials science.

An asymmetrical dysprosium trimer with a molecular formula of [Dy3(hq)7(hqH)(NO3)2(H2O)] was obtained through a reflux reaction employing as starting material Dy(NO3)3·nH2O and 8-quinolinoline as ligand. Magnetic susceptibility investigations show the system to be an SMM, which was corroborated by sub-Kelvin μSQUID studies. Upon cooling, the magnetic susceptibility also exhibits a decrease in the χMT product, which was confirmed to be due to intramolecular antiferromagnetic interactions. μSQUID measurements, moreover, reveal a marked magnetic behaviour in the angular dependence of the hysteresis loops. The latter is a direct consequence of the non-colinear spin arrangement of the anisotropy axes of each Dy(III) ion in [Dy3(hq)7(hqH)(NO3)2(H2O)] and the interaction between the ions, as also evidenced by CASSCF calculations. Our results evidence the effect of spin canting along with the intramolecular interactions, which can induce non-trivial magnetic behaviour in SMMs. [ABSTRACT FROM AUTHOR]

Two complex dysprosium(iii) salts of composition Na[Dy(hfac)4] (1) and Q[Dy(hfac)4]2(2), where hfac is the hexafluoroacetylacetonate anion and Q is 1,1′-dimethyl-4,4′-bipyridinium, were synthesized and studied by X-ray diffraction. An analysis of the X-ray diffraction data using the Shape program revealed noticeable distortions of two [DyO8] coordination polyhedra of salt 2 anions; the Dy atoms are nonequivalent and have a biaugmented trigonal prismatic (C2v) and triangular dodecahedral (D2d) geometry. The experimental studies and the analysis of the magnetic properties of 2 showed that this compound exhibits a field-induced slow relaxation of magnetization, which is described by the Orbach mechanism (Ueff = 23.0 K, τ0 = 2.68 · 10−8 s). [ABSTRACT FROM AUTHOR]

Currently, silumins, which are aluminum alloys, are most widely used in mechanical engineering, construction, and other industries. The use of silumins is often limited due to the presence of large-crystalline structures, such as α-Al dendrites, needle-shaped crystals of eutectic Si, and intermetallic phases. The effect of various additives on and their relationship with the microstructure and mechanical properties of Fe-containing intermetallic phases (Al–Si–Fe and Al–Si–Fe–Mn) has been studied extensively. However, studies of the effect of various additives on the morphology of Fe-containing phases in industrial Al–Si alloys remain relevant. The effect of small amounts of dysprosium titanate additives (0.01, 0.05, 0.1, 0.5 wt.%) on the morphology and localization of Fe-containing intermetallic phases is studied. Introducing 0.01 wt.% dysprosium titanate causes the transformation of the needle-shaped β-phase to the α-phase in the form of more compact blocks and polyhedral crystals, the size of the α-phase reducing by more than half. The introduction of 0.05, 0.1, and 0.5 wt.% dysprosium titanate does not change the modification of the α- and β-phases and reduces the size of the phases by a factor of 1.5 on average. After the introduction of dysprosium titanate, θ‑Al2Cu particles are dissolved and Cu is concentrated/localized in the Fe-containing intermetallic phases in all the modified alloys. After the introduction of 0.05–0.5 wt.% dysprosium titanate, the tensile strength of AK12 alloys increases due to a decrease in the size of the α- and β-phases. The modification of the Fe-containing intermetallic phases from the β-phase to the α-phase after the introduction of 0.1 wt.% dysprosium titanate decreases the tensile strength and elongation. The optimum is the addition of tungsten in the amount of 0.1 wt.%, as it leads to the optimal ratio between the structure and the mechanical properties. The tensile strength and elongation increase by 23% on average. [ABSTRACT FROM AUTHOR]

Integrating controllable spin states into single‐molecule magnets (SMMs) enables precise manipulation of magnetic interactions at a molecular level, but remains a synthetic challenge. Herein, we developed a 3d–4f metallacrown (MC) magnet [DyNi5(quinha)5(Clsal)2(py)8](ClO4) ⋅ 4H2O (H2quinha=quinaldichydroxamic acid, HClsal=5‐chlorosalicylaldehyde) wherein a square planar NiII is stabilized by chemical stacking. Thioacetal modification was employed via post‐synthetic ligand substitutions and yielded [DyNi5(quinha)5(Clsaldt)2(py)8](ClO4) ⋅ 3H2O (HClsaldt=4‐chloro‐2‐(1,3‐dithiolan‐2‐yl)phenol). Thanks to the additional ligations of thioacetal onto the NiII site, coordination‐induced spin state switching (CISSS) took place with spin state altering from low‐spin S=0 to high‐spin S=1. The synergy of CISSS effect and magnetic interactions results in distinct energy splitting and magnetic dynamics. Magnetic studies indicate prominent enhancement of reversal barrier from 57 cm−1 to 423 cm−1, along with hysteresis opening and an over 200‐fold increment in coercive field at 2 K. Ab initio calculations provide deeper insights into the exchange models and rationalize the relaxation/tunnelling pathways. These results demonstrate here provide a fire‐new perspective in modulating the magnetization relaxation via the incorporation of controllable spin states and magnetic interactions facilitated by the CISSS approach. [ABSTRACT FROM AUTHOR]

Two lanthanide complexes with formulae [DyIII(LN5)(pentafluoro-PhO)3] (1) and [DyIII(LN5)(2,6-difluoro-PhO)2](BPh4) (2) (LN5 = 2,14-dimethyl-3,6,10,13,19-pentaazabicyclo[13.3.1]nonadecal (19),2,13,15,17-pentaene) were structurally and magnetically characterized. DyIII ions lie in the cavity of a five coordinate nitrogen macrocycle, and in combination with the introduction of multi-fluorinated monodentate phenoxyl coligands a high axiality coordination symmetry is built. Using the pentafluorophenol co-ligand, complex 1 with a D2d coordination environment, is obtained and displays moderate single-molecule magnets (SMMs) behavior. When difluorophenol co-ligands were used, a higher local axisymmetric pentagonal bipyramidal coordination geometry was observed in complex 2, which displays apparent slow magnetic relaxation behavior with a hysteresis temperature of up to 5 K. Further magnetic studies of diluted samples combined with ab initio calculations indicate that the high axiality plays a crucial role in suppressing quantum tunneling of magnetization (QTM) and consequently results in good slow magnetic relaxation behavior. Different fluoro-substituted phenoxyl co-ligands have phenoloxy oxygen atoms with different electrostatic potentials as well as a different number of phenoloxy coligands along the magnetic axis, resulting in different ligand field strengths and coordination symmetries. [ABSTRACT FROM AUTHOR]

Dysprosium (Dy) is considered an important Rare Earth Element (REE) material in modern technology. However, due to its analogous chemical properties to other REEs, differentiating it within mixtures proves to be a challenging endeavor. Voltammetry has emerged as an alternative method for Dy determination, offering heightened sensitivity and fast analysis time. The selection of acetonitrile as the solvent is based on its broad potential range and exceptional conductivity. Additionally, the pursuit of optimal conditions through experimental design plays a pivotal role in identifying specific targets within mixtures. The combination of these methods is assumed to provide a satisfactory detection result. In this study, the Steepest Ascent and Box-Behnken designs were employed to optimize the conditions for Dy determination. The parameters subject to optimization included deposition potential, deposition time, and amplitude modulation. The outcome of this optimization process revealed the optimal conditions for Dy measurement via differential pulse voltammetry which are a deposition potential of -1.5171 V, deposition time of 76.0898 s, and amplitude modulation of 0.0860 V. Under these optimum conditions, the determination of Dy yielded a recovery rate of 99.47%, an accuracy of 97.06%, and a precision of 95.19%. Furthermore, the detection limit and quantitation limit values were found to be 2.1223 mg/L and 7.0744 mg/L, respectively. Moreover, the qualitative voltammetry result provides an insight into distinguishing Dy from Eu in the mixture. [ABSTRACT FROM AUTHOR]

Hexaazamacrocyclic Schiff bases have been extensively combined with lanthanoid (Ln) ions to obtain complexes with a highly axial geometry. However, the use of flexible hexaazatetraamine macrocycles containing two pyridines and acyclic spacers is rather uncommon. Accordingly, we obtained [DyL(OAc)2]OAc·7H2O·EtOH and [DyLMe2(Cl)2]Cl·2H2O, where L and LMe2 are the 18-membered macrocycles 3,6,10,13-tetraaza-1,8(2,6)-dipyridinacyclotetradecaphane and 3,10-dimethyl-3,6,10,13-tetraaza-1,8(2,6)-dipyridinacyclotetradecaphane, respectively, which contain ethylene and methylethylene spacers between their N3 moieties. [DyL(OAc)2]OAc·7H2O·EtOH represents the first crystallographically characterized lanthanoid complex of L, while [DyLMe2(Cl)2]Cl·2H2O contributes to increasing the scarce number of LnIII compounds containing LMe2. Furthermore, the crystal structure of L·12H2O was solved, and it was compared with those of other related macrocycles previously published. Likewise, the crystal structures of the DyIII complexes were compared with those of the lanthanoid and d-metal complexes of other 18-membered N6 donor macrocycles. This comparison showed some effect of the spacers employed, as well as the influence of the size of the ancillary ligands and the metal ion. Additionally, the distinct folding behaviors of these macrocycles influenced their coordination geometries. Moreover, the luminescent properties of [DyL(OAc)2]OAc·7H2O·EtOH and [DyLMe2(Cl)2]Cl·2H2O were also investigated, showing that both complexes are fluorescent, with the emission being sensitized by the ligands. [ABSTRACT FROM AUTHOR]

Two uranium oxide hydrate frameworks (UOHFs) with either Dy3+ or Lu3+ ions, Dy1.36(H2O)6[(UO2)10UO13(OH)4] (UOHF‐Dy) or Lu2(H2O)8[(UO2)10UO14(OH)3] (UOHF‐Lu), were synthesized hydrothermally and characterized with a range of structural and spectroscopic techniques. Although SEM‐EDS analysis confirmed the same atomic ratio of ~5.5 for U : Dy and U : Lu, they displayed different crystal morphologies, needles for UOHF‐Dy in the orthorhombic C2221 space group and plates for UOHF‐Lu in the triclinic P‐1 space group. Both frameworks are composed of β‐U3O8 type layers linked by pentagonal bipyramidal uranium polyhedra, with the Dy3+/Lu3+ ions inside the channels. However, the arrangements of Dy3+/Lu3+ ions are different, with disordered Dy3+ ions well aligned at the centers of the channels and single Lu3+ ions well‐separated in a zigzag pattern in the channels. While the characteristic vibrational modes were revealed by Raman spectroscopy, the presence of a pentavalent uranium center in UOHF‐Lu was confirmed with diffuse reflectance spectroscopy. The formation of two types of UOHFs with lanthanide ions, high or low symmetry, and the structure trend were discussed regards to synthesis conditions and lanthanide ionic radius. This work highlights the complex chemistry driving the formation of UOHFs with lanthanide ions and has implications to the spent nuclear fuel under geological disposal. [ABSTRACT FROM AUTHOR]

Background: This study focuses on the synthesis of magnesium‐doped dysprosium chromite via a sol‐gel method. The investigation aims to understand the morphological and structural properties of the synthesized nanochromates. Key techniques employed include x‐ray diffraction (XRD), scanning electron microscopy (SEM), and Raman spectroscopy. Aims: The primary aim is to analyze the structural characteristics of MgxDy1−xCr2O4 nanoparticles with varying Mg doping concentrations (ranging from 0.2 to 0.8). Special attention is given to the crystallinity of the synthesized materials, with the goal of assessing the reliability and reproducibility of the sol‐gel synthesis method. Methods: XRD analysis is employed to identify major diffraction peaks associated with the chromate nanoparticles, providing insights into their crystallinity. SEM imaging allows for the examination of the morphological features of the synthesized materials. Additionally, Raman spectroscopy aids in further understanding the structural properties of the nanochromates. Results: The XRD analysis reveals average crystallite sizes for MgxDy1−xCr2O4 nanoparticles at different Mg doping concentrations. Notably, an improvement in crystalline quality is observed with an increase in Mg doping from 0.2 to 0.8, indicating a high level of control achieved in the synthesis process. Cyclic Voltammetry (CV) experiments conducted using a 1M KOH electrolyte and varying scan rates (3 mV/s to 50 mV/s) demonstrate enhanced electrochemical performance of the synthesized nanoparticles. Conclusion: The study concludes that the sol‐gel synthesis method effectively produces MgxDy1−xCr2O4 nanoparticles with controlled morphological and structural properties. The observed improvement in crystalline quality with increasing Mg doping concentration suggests potential applications in fields such as photo‐catalysis, where enhanced crystallinity correlates with improved photo‐catalytic potential for visible light absorption. [ABSTRACT FROM AUTHOR]

This paper studies the dynamics of the development of laser breakdown plasma in aqueous colloids of dysprosium nanoparticles by analyzing the time patterns of plasma images obtained using a high-speed streak camera. In addition, the distribution of plasma flashes in space and their luminosity were studied, and the amplitude of acoustic signals and the rate of generation of new chemical products were studied depending on the concentration of dysprosium nanoparticles in the colloid. Laser breakdown was initiated by pulsed radiation from a nanosecond Nd:YAG laser. It is shown that the size of the plasma flash, the speed of motion of the plasma–liquid interface, and the lifetime of the plasma flash decrease with an increasing concentration of nanoparticles in the colloid. In this case, the time delay between the beginning of the laser pulse and the moment the plasma flash reaches its maximum intensity increases with increasing concentrations of nanoparticles. Varying the laser fluence in the range from 67 J/cm2 to 134 J/cm2 does not lead to noticeable changes in these parameters, due to the transition of the breakdown plasma to the critical regime. For dysprosium nanoparticles during laser breakdown of colloids, a decrease in the yield of hydrogen peroxide and an increase in the rate of formation of hydroxyl radicals per water molecule, characteristic of nanoparticles of rare earth metals, are observed, which may be due to the participation of nanoparticles and hydrogen peroxide in reactions similar to the Fenton and Haber–Weiss reactions. [ABSTRACT FROM AUTHOR]

Micro-wave assisted combustion synthesis technique was adopted to synthesize the dysprosium-doped yttrium calcium borate xDy3+: Y (2-x) CaB 10 O 19 (Dy:YCB) polycrystalline phosphor materials with varying concentrations (x = 1, 3, 5, 7 and 9 mol %) for the first time. The formation of phase, crystal structure was analyzed by x-ray diffraction study and was affirmed to be formed pertaining to the monoclinic crystal structure (a = 11.475 Å, b = 6.345 Å, c = 9.223 Å and α = γ = 90°, β = 91.83°) with C2 space group. The absorption capability of the prepared samples was investigated by UV-DRS spectroscopy and the optical band gap was found to be 5.28 eV. FTIR study validated the presence of functional groups and their molecular vibrations. The excitation wavelength of the synthesized samples was found to be 350 nm from photoluminescence excitation (PLE) spectra. The PL emission spectra were recorded to authenticate the emission wavelengths and found to possess two emission peaks at 480 nm (blue) and 577 nm (yellow) contributed by the Dy3+ ions. The optimized dopant concentration of dysprosium ion was fixed at x = 0.07 to avoid the concentration quenching effect. The chromaticity co-ordinate of optimized sample was determined to be x = 0.3188, y = 0.3233 which are closer to ideal white light co-ordinate. The color temperature was determined to be 6209 K, which occurs in the cool white light region. Luminous efficacy of radiation (LER) was determined to be 269.31 l m/W opt for the optimal phosphor. The luminous efficiency for the optimal phosphor was determined to be 40%. Color rendering index (CRI) of the optimal sample was evaluated to be 77. Internal quantum yield (IQE) of the optimal sample was determined to be 50.58 %. The phosphor materials have excellent thermal stability as validated from the temperature dependent PL measurements. [ABSTRACT FROM AUTHOR]

Interaction of Pr/Dy with oxygen in nickel melts at PAr = 0.1 MPa and constant temperature was studied using the EMF instantaneous fixing method using a Mo[Cr/Cr2O3//ZrO2(MgO)//O(Nil)]Mo cell and certified sensors. Dependences a[O] = f[Pr/Dy, %] expressed in the form of logarithmic equations made it possible to compare them with each other in the concentration range of 0.001–0.2 wt % of each deoxidizer and determine that the deoxidizing ability of Pr is 1.7 times higher compared to Dy. The activity of oxygen a[O] in Ni–O–Al–(Pr/Dy) melts was calculated in comparison with Al at a concentration of 0.05 wt % of elements and its sevenfold decrease was shown for the first deoxidizer and elevenfold for the second. The morphology of nonmetallic inclusions in metallographic sections of Ni–O–Pr/Dy alloys has been studied, indicating that the inclusions are located along grain boundaries and have different configurations and a complex heterophase composition. Analysis of nonmetallic inclusions with the maximum content of deoxidizing element proved the existence of Pr/Dy oxygen compounds, which confirmed the data of thermodynamic and mass spectrometric studies. The average content of Zr in nonmetallic inclusions during the deoxidation of Pr is two times higher than in experiments during the deoxidation of Dy, which indicates the interaction of Pr/Dy with the EMF ZrO2 sensor and the preferential interaction of Pr compared to Dy and correlates with the data on the determination of a[O]. [ABSTRACT FROM AUTHOR]

This paper studies the dynamics of the development of laser breakdown plasma in aqueous colloids of dysprosium nanoparticles by analyzing the time patterns of plasma images obtained using a high-speed streak camera. In addition, the distribution of plasma flashes in space and their luminosity were studied, and the amplitude of acoustic signals and the rate of generation of new chemical products were studied depending on the concentration of dysprosium nanoparticles in the colloid. Laser breakdown was initiated by pulsed radiation from a nanosecond Nd:YAG laser. It is shown that the size of the plasma flash, the speed of motion of the plasma–liquid interface, and the lifetime of the plasma flash decrease with an increasing concentration of nanoparticles in the colloid. In this case, the time delay between the beginning of the laser pulse and the moment the plasma flash reaches its maximum intensity increases with increasing concentrations of nanoparticles. Varying the laser fluence in the range from 67 J/cm2 to 134 J/cm2 does not lead to noticeable changes in these parameters, due to the transition of the breakdown plasma to the critical regime. For dysprosium nanoparticles during laser breakdown of colloids, a decrease in the yield of hydrogen peroxide and an increase in the rate of formation of hydroxyl radicals per water molecule, characteristic of nanoparticles of rare earth metals, are observed, which may be due to the participation of nanoparticles and hydrogen peroxide in reactions similar to the Fenton and Haber–Weiss reactions.

The efficient and reliable treatment of both spin–orbit coupling (SOC) and electron correlation is essential for understanding f-element chemistry. We analyze two approaches to the problem: the one-step approach, where both effects are treated simultaneously, and the two-step state interaction approach. We report an implementation of the ab initio density matrix renormalization group with a one-step treatment of the SOC effect, which can be compared to prior two-step treatments on an equal footing. Using a dysprosium octahedral complex and bridged dimer as benchmark systems, we identify characteristics of problems where the one-step approach is beneficial for obtaining the low-energy spectrum. [ABSTRACT FROM AUTHOR]

Two five‐coordinate mononuclear DyIII single‐molecule magnets [(TrapenTMS)Dy(L)] (Trapen=tris(2‐aminobenzyl) amine; TMS=SiMe3; L=OPMe31, OPEt32) have been synthesized by the reaction of [(TrapenTMS)Dy(THF)] and OPMe3, OPEt3, respectively. The molecular structures of 1 and 2 were fully established by single crystal X‐ray diffraction. The centre DyIII ions of both complexes exhibit distorted triangular bipyramid geometries, varying with different neutral ligands L on the apex. The TrapenTMS ligand forms the pyramid base of the trigonal bipyramid. Subtle structural modifications of the axial O‐ligand terminal substituent result in different dynamic magnetic behaviors. Magnetic data analysis reveals that 1 and 2 exhibit the characteristic behavior of SMM without a dc field, accompanying an unambiguous quantum tunneling of the magnetization. Field‐induced slow magnetic relaxation was observed for 1 and 2 under an applied bias dc field of 1000 Oe, the relaxation energy barriers are 107 K and 88 K for 1 and 2, respectively. We have investigated the differences in magnetism and magnetic anisotropy between the two complexes by ab initio calculations. [ABSTRACT FROM AUTHOR]

Dinuclear lanthanide complexes [((HB(pz)3)2Dy)2(μ-Th2An)] (1Dy) and [((HB(pz)3)2Dy)2(μ-ClCNAn)] (2Dy), based on the hydrotris(pyrazol-1-yl)borate (HBpz3−) scorpionate capping ligand and anilate (An2−) bridging linkers, namely homosubstituted dithiophene- and heterosubstituted chlorocyanoanilate, bearing electron-donating and withdrawing substituents at the 3,6-positions of the benzoquinone core, are reported. 1Dy shows an octacoordinated {N6O2} DyIII ion within a D4h distorted square antiprismatic coordination, an ideal geometry for Single-Molecule Magnet (SMM) behavior, given its oblate nature, whereas in 2Dy the octacoordinated DyIII ion adopts a D2d triangular dodecahedron geometry, while maintaining the same {N6O2} coordination sphere. Both complexes show field-induced single molecule magnet (SMM) behaviour, with tuning of the slow magnetic relaxation as a function of the nature of the substituents at the 3,6-positions of the anilate moiety. A comparison of the Arrhenius fitting parameters for 1Dy and 2Dy supports the hypothesis that square antiprismatic DyIII complexes, as 1Dy, exhibit higher energy barriers. This interpretation is supported by ab initio calculations that also shed light on the crucial role of intermolecular dipolar interactions. [ABSTRACT FROM AUTHOR]

Controlling ultracold atoms with laser light has greatly advanced quantum science. The wavelength of light sets a typical length scale for most experiments to the order of 500 nanometers (nm) or greater. In this work, we implemented a super-resolution technique that localizes and arranges atoms on a sub- 50-nm scale, without any fundamental limit in resolution. We demonstrate this technique by creating a bilayer of dysprosium atoms and observing dipolar interactions between two physically separated layers through interlayer sympathetic cooling and coupled collective excitations. At 50-nm distance, dipolar interactions are 1000 times stronger than at 500 nm. For two atoms in optical tweezers, this should enable purely magnetic dipolar gates with kilohertz speed. [ABSTRACT FROM AUTHOR]

In the present study, commercially available different sources of magnesia and alumina were used to produce reaction sintered magnesium aluminate spinel (MgAl2O4). Initially, spinel with stoichiometric composition was prepared from three different sources of Al2O3 and two sources of MgO and then the effect of dysprosia (Dy2O3) in a concentration range of 1–4 wt.% on the sintered properties of spinels was studied in the temperature range of 1550–1650°C. The densities of the doped compositions were higher compared with the undoped ones, and the maximum density was found for the 1 wt.% Dy2O3‐doped samples. Phase analysis and microstructural studies revealed that formation of dysprosium aluminum garnet (Dy3Al5O12) phase along the intergranular positions, which served as grain‐growth inhibitors and improved densification. Further, 1 wt.% Dy2O3‐doped compositions also revealed better flexural strength and retained strength post thermal shock values than undoped spinel. [ABSTRACT FROM AUTHOR]

In this work, a novel white light emitting Dy3+ doped NaPbBi2(PO4)3 phosphors were synthesized for WLEDs application. The phase formation, morphological analysis and elemental composition of the prepared phosphors were investigated. The optical spectra revealed the nature of bonding (Dy3+ ions–ligand) and the band gap value of the optimized phosphor. The photometric analysis (PLE, PL spectra and lifetime value) at the room temperature and in the temperature range of 303–483 K were investigated. Exciting the phosphors at the near UV light gave rise to predominant emission in the blue and yellow region of the visible spectrum. The dipole–dipole interactions between the Dy3+ ions leads to concentration quenching effect which occured at 0.09 mol. The Judd–Ofelt intensity parameters were computed and the information about the radiative properties were attained through them. The emission of cool light (5474 K) with color purity 3.69%, lifetime time value of 0.631 ms and good thermal stability suggested that these phosphor is a potential candidate for WLEDs application. [ABSTRACT FROM AUTHOR]

The reaction of [(Dpp-bian)DyI(Dme)2] (Dpp-bian is 1,2-bis[(2,6-diisopropylphenyl)imino]acenaphthene, Dme is CH3OCH2CH2OCH3) with Cp*K (Cp* is C5Me5) in toluene followed by crystallization from benzene affords crystals of the 1D coordination polymer [(Dpp-bian)DyIKCp*]n (I)·2.6C6H6 (26%) and crystals of the monomeric complex [(Dpp-bian)DyCp*(Dme)] (II)·1.5C6H6 (12%). The same reaction in 1,2-dimethoxyethane followed by crystallization from benzene makes it possible to isolate only complex II·1.5C6H6 in a yield of 48%. The synthesized compounds are characterized by IR and UV spectroscopy and elemental and thermogravimetric analyses. Their molecular structures are determined by XRD (CIF files CCDC nos. 2298407 (I) and 2298408 (II)). [ABSTRACT FROM AUTHOR]

High‐performance and air‐stable single‐molecule magnets (SMMs) can offer great convenience for the fabrication of information storage devices. However, the controversial requisition of high stability and magnetic axiality is hard to balance for lanthanide‐based SMMs. Here, a family of dysprosium(III) crown ether complexes possessing hexagonal‐bipyramidal (pseudo‐D6h symmetry) local coordination geometry with tunable air stability and effective energy barrier for magnetization reversal (Ueff) are shown. The three complexes share the common formula of [Dy(18‐C‐6)L2][I3] (18‐C‐6 = 1,4,7,10,13,16‐hexaoxacyclooctadecane; L = I, 1; L = OtBu 2 and L = 1‐AdO 3). 1 is highly unstable in the air. 2 can survive in the air for a few minutes, while 3 remains unchanged in the air for more than 1 week. This is roughly in accordance with the percentage of buried volumes of the axial ligands. More strikingly, 2 and 3 show progressive enhancement of Ueff and 3 exhibits a record high Ueff of 2427(19) K, which significantly contributes to the 100 s blocking temperature up to 11 K for Yttrium‐diluted sample, setting a new benchmark for solid‐state air‐stable SMMs. [ABSTRACT FROM AUTHOR]

The coordination of hydrotris[3‐(2‐furyl)pyrazol‐1‐yl]borate (Tp2‐Fu, C21H16BN6O3) to lanthanide(III) ions is achieved for the first time with the complex [Ln(Tp2‐Fu)2](BPh4)·xCH2Cl2 (1‐Ln has Ln = Ce and x = 2; 1‐Dy has Ln = Dy and x = 1). This was accomplished via both hydrous (Ln = Ce) and anhydrous methods (Ln = Dy). When isolating the dysprosium analogue, the filtrate produced a second crop of crystals which were revealed to be the 1,2‐borotropic‐shifted product [Dy(κ4‐Tp2‐Fu)(κ5‐Tp2‐Fu*)](BPh4) (2) {Tp2‐Fu* = hydrobis[3‐(2‐furyl)pyrazol‐1‐yl][5‐(2‐furyl)pyrazol‐1‐yl]borate}. We conclude that the presence of a strong Lewis acid and a sterically crowded coordination environment are contributing factors for the 1,2‐borotropic shifting of scorpionate ligands in conjunction with the size of the conical angle with the scorpionate ligand. [ABSTRACT FROM AUTHOR]

The ultrasonic characteristics of dysprosium monochalcogenides, DyX (X = S, Se and Te) as a function of temperature and crystallographic direction, are studied in present investigation. First, the second- and third-order elastic constants (SOECs and TOECs) have been computed using Coulomb and Born-Mayer potential from 0K to 500K. The mechanical properties have been evaluated with the achieved values of SOECs for finding the intrinsic properties, stability and futuristic performance of DyX. The mechanical stability and elastic moduli follow the order DyS > DySe > DyTe. Supplemental the acoustic velocities including Debye average velocity, thermal relaxation time, Debye temperature and nonlinear parameter have been computed along <100>, <110> and <111> directions in the temperature range 100K to 500K. The Debye average velocity is found to be highest for wave propagating along <110> and polarized along <...0>. Finally, the ultrasonic attenuation using the modified Mason's approach has been computed in the temperature regime 100-500K along different crystallographic directions and calculated results predict that Akheiser damping dominates over the thermal attenuation. The obtained results have been analyzed and discussed with the available literature. [ABSTRACT FROM AUTHOR]

Three borosilicate glass samples of 25 % Si 2 O – 30 % Na 2 O – 45 % B 2 O 3 doped with x Dy 2 O 3 (where x = 0, 2, and 4 mol %) were prepared using the melt quenching technique. Photoluminescence spectra for glass samples were studied when excited by 350 nm in the 400–800 nm range, where emission sharply increases for samples doped with 2 % Dy 2 O 3 (BSNDy2) at 580 nm after exposed to 30 kGy. Also, glass containing 2 % Dy photoluminescence constants, such as decay curves CIE chromaticity, was measured for all samples that gave three decay behaviors: slow, intermediate, and fast. Experimental lifetime (τ exp.), color coordination (X, Y), and yellow/blue intensity ratio (y/b) beside the color correlated temperature (CCT) were determined before and after being irradiated by 30 and 60 kGy from γ ray source where the y/b ratio of BSNDy2 increase by increasing exposure to gamma doses and were >1. In addition, electrical conductivity at different temperatures was investigated as the BSNDy2 sample gave the highest conductivity and decreased by BSNDy4. Moreover, shielding parameters such as the tenth value layer, half value layer, mean free path and mass attenuation coefficient values were calculated at different gamma-ray energies via the Phy-X program, showing the highest values for MAC, Z eff , N eff, and C eff for BSNDy4 sample. The findings showed that adding Dy 2 O 3 to the glass gave a fortified shielding character. [ABSTRACT FROM AUTHOR]

Considering the growing interest in lanthanide‐based multifunctional materials two mixed‐ligand complexes [Ln(L)3bipy] (Ln=TbIII, DyIII) with carbacylamidophosphate (CAPh) type ligand – dimethyl‐N‐trichloroacetylamidophosphate (HL) and additional bidentate ligand 2,2'‐bipyridine (bipy) were obtained and studied by X‐ray diffraction study, thermal gravimetric analysis, and luminescence spectroscopy. The obtained complexes are monomeric and isostructural with earlier reported europium analog and crystallizes in the monoclinic system (space group C2/c). They are stable during long‐term storage for at least a couple of years as well as thermally stable up to nearly 200 °C. Both complexes exhibit f–f luminescence upon excitation into the 2,2'‐bipyridine absorption band, being emitters of green (TbIII) and yellow (DyIII) light. The luminescence intensity of the obtained complexes decreases constant exposure to UV radiation for several hours and then stays constant for at least till 32 h. [ABSTRACT FROM AUTHOR]

The beneficial effects of lanthanide incorporation into 0.94Na0.5Bi0.5TiO3-0.06BaTiO3 (BNT-BT) matrix on its functional properties were investigated. The conventional solid-state method was used for synthesizing samples. The structural refinement revealed that all samples crystallized in R3c rhombohedral symmetry. Raman spectroscopy study was carried out using green laser excitation and revealed that no clear perceptible variation in frequency is observed. Dielectric measurements unveiled that the introduction of rare earth obstructed the depolarization temperature promoted in BNT-BT, the diffusive phase transition decreasing with increasing lanthanide size. Only dysprosium addition showed comparable diffusion constant and dielectric behavior as the unmodified composition. Further, the comparison of the obtained ferroelectric hysteresis and strain-electric field loops revealed that only Dy-phase exhibited interesting properties comparing parent composition. In addition, the incorporation of lanthanides Ln3+ into the BNT-BT matrix led to the development of luminescence characteristics in the visible and near infrared regions, depending on the excitation wavelengths. The simultaneous occurrence of photoluminescence and ferroelectric/piezoelectric properties opens up possibilities for BNT-BT-Ln to exhibit multifunctionality in a wide range of applications. [ABSTRACT FROM AUTHOR]

The multi-anionic compound with the composition Dy36O11F50 [AsO3]12 · H2O, which can be described in the non-centrosymmetric cubic space group F43c, already shows an unusually large unit cell with an axis of a = 2587.59(14) pm. Its crystal structure exhibits isolated ψ¹-tetrahedral [AsO3]3- anions, but both the coordination numbers and the linking schemes of the Dy3+-centered polyhedra differ significantly from the mostly layered structures described so far in literature. (Dy1)3+ is sevenfold coordinated by oxygen atoms and F- anions, forming a capped trigonal prism [(Dy1)O4.333F2.667]8.333-, and the remaining two cations (Dy2)3+ and (Dy3)3+ both reside in an eightfold coordination of anions. In both cases they form slightly distorted square antiprisms, which have the compositions of [(Dy2)O3.667F4.333]8.667- and [(Dy3)O4.667F3.333]9.667-, respectively. Some of the oxygen atoms are not part of ψ¹-[AsO3]3- tetrahedra, but occur as O2- anions and one of these even shares a common crystallographic position with fluoride (F-). It is also worth mentioning that the single crystals were obtained as comparatively large cubes with an edge length of several 100 μm providing very good data with regard to single-crystal X-ray diffraction. To verify the simultaneous presence of oxygen and fluorine, electron-beam microprobe analysis was carried out, and a single-crystal Raman spectrum ruled out the presence of hydroxide anions or protonated [AsO3]3- groups, but proved the interstitial crystal-water molecules, which could not be determined precisely by the crystal-structure refinement. [ABSTRACT FROM AUTHOR]

Multi-peak (blue–yellow–red) with warm white light generation of Dy3+ ions-activated zinc leadfluoride-based sodium phosphate (NPZ:60NaPO3 + 25PbF2 + 15ZnF2) glasses were fabricated via the melt and rapid quenching method. The X-ray diffractogram and Raman spectra were studied to examine the amorphous and network structures of NPZDy glasses. The evaluated molar volume and density values increased with the rise in the amount of Dy3+ ions due to the formation of more non-bridging oxygen in the glass network. The result revealed that the Dy3+ ions-doped NPZDy glasses could absorb from 300 to 1800 nm wavelengths and then determined the bandgap energies of NPZDy glasses by using the Tauc's plots. Upon 348 nm of ultraviolet radiation, the fabricated glasses emit red (665 nm), yellow (576 nm), and blue (482 nm) light from the 4F9/2 → 6H11/2,13/2,15/2 transitions of Dy3+ ion. The influence of various molar fraction of Dy3+ ions on the Ω2,4,6 and radiative properties of NPZDy glasses were studied by applying the Judd–Ofelt analysis. The decay times were evaluated by fitting the NPZDy glasses' decays to the bi-exponential function. The larger gain bandwidth of 83.21 × 10–28 cm3 and the maximum quantum efficiency of 79% for NPZDy glasses were calculated by the production of warm white light with (x, y) coordinates of (0.321, 0.361) and relative color temperature of < 4000 K. [ABSTRACT FROM AUTHOR]

The Sr1-3x/2DyxTiO3 (x = 0.005, 0.01, 0.015, 0.02, 0.04, 0.06) ceramics are prepared sintered in N2 / air through a solid-state synthesis method. The effects of Dy doping amount and sintering process on the structure and dielectric properties of Sr1-3x/2DyxTiO3 ceramics were systematically investigated. We identify a novel Sr1-3x/2DyxTiO3 ceramic system sintered in N2 that exhibits the most superior dielectric performance when x = 0.01. At room temperature, the εr and tanδ of Sr0.985Dy0.01TiO3 ceramic sintered in N2 are 29,000 and 0.07 at a frequency of 1 kHz, and 27,000 and 0.01 at a frequency of 10 kHz, respectively. Additionally, the εr of Sr0.985Dy0.01TiO3 ceramics sintered in N2 has an excellent temperature stability at high temperatures, with a change rate within the range of ± 15% at a frequency of 10 kHz ranging from 30 to 480 ℃. Through comparing Sr0.985Dy0.01TiO3 ceramic sintered in air, sintering in N2 significantly improved its εr and thermal stability. This study demonstrates that the improvement of processing techniques and doping strategies have enhanced the dielectric properties of the ceramics. [ABSTRACT FROM AUTHOR]

Mesoporous silica gel doped with dysprosium, lanthanum and modified with silver (Dy-Ag/MPS, La-Ag/MPS) was obtained by the template method. The physicochemical characteristics of the obtained catalyst were studied by scanning electron microscopy, X-ray fluorescence and X-ray diffraction analysis, inductively coupled plasma mass spectrometry and temperature-programmed reduction. In addition, the possibility of using obtained materials as an efficient and selective catalysts in the hydrogenation of a 1-heptyne/1-heptene mixture (with 30% of alkyne content) in a temperature range of 140–160 °C and a hydrogen pressure of 3 atm was studied. It was found that after 15 min from the start of the hydrogenation reaction at 140 °C on the La-Ag/MPS catalyst, total conversion of 1-heptyne was observed and selectivity for 1-heptene was 84%. Moreover, it was shown that on a Dy-Ag/MPS at 150 °C 1-heptyne conversion was 84%, the selectivity for alkene was 79%. Furthermore, with an increase in temperature to 160 °C, the conversion of 1-heptyne reaches 95%, the selectivity for 1-heptene—84%. [ABSTRACT FROM AUTHOR]

Using the auto combustion sol-gel method, nanoferrite crystalline aligns of Dy3+ replaced Zn-Fe spinel ferrite with the chemical formula DyxZn1-xFe2-xO4 (x= 0.00, 0.05) were successfully synthesized. In this process, citric acid was utilized as energy (fuel) in a 3:1 ratio to metal nitrate. Using XRD and FT-IR, the crystal structure and phase of dysprosium zinc was examined. Using the XRD method, the crystal size, lattice constant, cation distribution, and porosity were ascertained. FT-IR spectroscopy is used to infer structural study and the redistribution of cations between octahederal (A) and tetrahederal (B) site of Zn material. According to morphological research, the temperature during sintering is what causes grain to form and grow. Utilizing the Hysteresis Loop Technique, saturation magnetism and magneton number are determined. In Zn-Fe ferrite, the saturation magnetization rises with increasing density x, utilizing the Sol-gel auto-combustion method at a comparatively low temperature. Using nitrate citrate, the nanocrystallite DyxZn1-xFe2-xO4 was created. The combustion process and chemical gelation are unique. Using citric acid as a catalyst, their metal nitrates nanoferrites underwent a successful chemical reaction and were obtained as a dried gel. FT-IR, UVVisible, VSM and XRD were used to characterize the produced nanoferrite powders. Magnetization and hysteresis were measured using the VSM technique. The FT-IR verifies that the synthesized substance is ferrite. The size of the nanocrystalline ferrite material, DyxZn1-xFe2-xO4, was determined by X-ray using the Scherrer method to be between 16.86 to 12.72 nm average crystallite size. Magnetization and hysteresis were measured using the VSM technique. [ABSTRACT FROM AUTHOR]